Frustrated Total Internal Reflection: A Simple Application and Demonstration.
ERIC Educational Resources Information Center
Zanella, F. P.; Magalhaes, D. V.; Oliveira, M. M.; Bianchi, R. F.; Misoguti, L.; Mendonca, C. R.
2003-01-01
Describes the total internal reflection process that occurs when the internal angle of incidence is equal to or greater than the critical angle. Presents a demonstration of the effect of frustrated total internal reflection (FTIR). (YDS)
Resonant tunneling in frustrated total internal reflection.
Longhi, Stefano
2005-10-15
Anomalous light transmission and resonant tunneling in frustrated total internal reflection (FTIR) are theoretically predicted to occur at periodically curved interfaces. For a low-contrast index and for grazing incidence, it is shown that FTIR resonant tunneling provides an optical realization of field-induced barrier transparency in quantum tunneling.
Novel method in solving non-polarizing condition in frustrated total internal reflection layers
NASA Astrophysics Data System (ADS)
Shi, Jin Hui; Wang, Zheng Ping
2008-03-01
When used at oblique angles of incidence, the reflectance and transmittance of thin films exhibit strong polarization effects, particularly for the films inside a glass cube. However, the polarization effects are undesirable in many applications. Novel non-polarizing beam splitter designs are shown, non-polarizing beam splitters with unique optical thin films are achieved through combination of interference and frustrated total internal reflection, the non-polarizing condition expressions based on frustrated total internal reflection is derived, and applied examples of the non-polarizing beam splitters are also presented with the optimization technique and the results of Rp=(50+/-0.4)% and Rs=(50+/-0.4)% in the wavelength range of 500-600nm are obtained.
Frustrated total internal reflection acoustic field sensor
Kallman, Jeffrey S.
2000-01-01
A frustrated total internal reflection acoustic field sensor which allows the acquisition of the acoustic field over an entire plane, all at once. The sensor finds use in acoustic holography and acoustic diffraction tomography. For example, the sensor may be produced by a transparent plate with transparent support members tall enough to support one or more flexible membranes at an appropriate height for frustrated total internal reflection to occur. An acoustic wave causes the membrane to deflect away from its quiescent position and thus changes the amount of light that tunnels through the gap formed by the support members and into the membrane, and so changes the amount of light reflected by the membrane. The sensor(s) is illuminated by a uniform tight field, and the reflection from the sensor yields acoustic wave amplitude and phase information which can be picked up electronically or otherwise.
Hull, J R
1989-01-01
Coupling a dielectric compound parabolic concentrator (DCPC) to an absorber across a vacuum gap by means of frustrated total internal reflection (FTIR) can theoretically approach the maximum concentration permitted by physical laws, thus allowing higher radiative fluxes in thermal applications. The calculated optical performance of 2-D DCPCs with FTIR absorbers indicates that the ratio of gap thickness to optical wavelength must be <0.22 before the optical performance of the DCPC is superior to that of the nondielectric CPC.
Nonpolarizing beam splitter designed by frustrated total internal reflection inside a glass cube.
Xu, Xueke; Shao, Jianda; Fan, Zhengxiu
2006-06-20
A method for the design of an all-dielectric nonpolarizing prism beam splitter utilizing the principle of frustrated total internal reflection is reported. The nonpolarizing condition for a prism beam splitter is discussed, and some single layer design examples are elaborated. The concept can be applied to a wide range of wavelengths and arbitrary transmittance values, and with the help of a computer design program examples of 400-700 nm, T(p)=T(s)=0.5+/-0.01, with incident angles of 45 degrees and 62 degrees are given. In addition, the sensitivity and application of the design are also discussed.
Theoretical analysis of non-polarizing beam splitters with appropriate amplitude and phase
NASA Astrophysics Data System (ADS)
Shi, Jin Hui; Wang, Zheng Ping; Guan, Chun Ying
2009-04-01
When used at oblique angles of incidence, the reflectance and transmittance of thin films exhibit strong polarization effects, particularly for the films inside a glass cube. However, the polarization effects are undesirable in many applications. Novel non-polarizing beam splitter designs are shown. Non-polarizing beam splitters with unique optical thin films are achieved through the combination of interference and frustrated total internal reflection. The non-polarizing condition expressions based on frustrated total internal reflection are derived, and examples of the non-polarizing beam splitters are also presented with the optimization technique and the results of Rp=(50±0.5)%, Rs=(50±0.5)%, and Δr=(0±0.3) in the wavelength range of 400-700 nm are obtained.
Design and analysis of non-polarizing beam splitter in a glass cube
NASA Astrophysics Data System (ADS)
Shi, Jinhui; Wang, Zhengping; Huang, Zongjun; Li, Qingbo
2008-11-01
The reflectance and transmittance of thin films at oblique incident angles exhibit strong polarization effects, particularly for the films inside a glass cube. However, the polarization effects are undesirable in many applications. To solve this problem, non-polarizing beam splitters with unique optical thin films have been achieved employing a method of combination of interference and frustrated total internal reflection, the non-polarizing condition expressions based on frustrated total internal reflection has been derived, and the design examples of non-polarizing beam splitters with an optimization technique have been also presented. The results of Rp=(50+/-0.5)%, Rs=(50+/-0.5)% andΔr=(0+/-0.3) degree in the wavelength range of 400-700nm have been obtained. The thickness sensitivity of NPBSs is also analyzed.
Watch your step! A frustrated total internal reflection approach to forensic footwear imaging
NASA Astrophysics Data System (ADS)
Needham, J. A.; Sharp, J. S.
2016-02-01
Forensic image retrieval and processing are vital tools in the fight against crime e.g. during fingerprint capture. However, despite recent advances in machine vision technology and image processing techniques (and contrary to the claims of popular fiction) forensic image retrieval is still widely being performed using outdated practices involving inkpads and paper. Ongoing changes in government policy, increasing crime rates and the reduction of forensic service budgets increasingly require that evidence be gathered and processed more rapidly and efficiently. A consequence of this is that new, low-cost imaging technologies are required to simultaneously increase the quality and throughput of the processing of evidence. This is particularly true in the burgeoning field of forensic footwear analysis, where images of shoe prints are being used to link individuals to crime scenes. Here we describe one such approach based upon frustrated total internal reflection imaging that can be used to acquire images of regions where shoes contact rigid surfaces.
Watch your step! A frustrated total internal reflection approach to forensic footwear imaging.
Needham, J A; Sharp, J S
2016-02-16
Forensic image retrieval and processing are vital tools in the fight against crime e.g. during fingerprint capture. However, despite recent advances in machine vision technology and image processing techniques (and contrary to the claims of popular fiction) forensic image retrieval is still widely being performed using outdated practices involving inkpads and paper. Ongoing changes in government policy, increasing crime rates and the reduction of forensic service budgets increasingly require that evidence be gathered and processed more rapidly and efficiently. A consequence of this is that new, low-cost imaging technologies are required to simultaneously increase the quality and throughput of the processing of evidence. This is particularly true in the burgeoning field of forensic footwear analysis, where images of shoe prints are being used to link individuals to crime scenes. Here we describe one such approach based upon frustrated total internal reflection imaging that can be used to acquire images of regions where shoes contact rigid surfaces.
Relations of Effortful Control, Reactive Undercontrol, and Anger to Chinese Children’s Adjustment
Eisenberg, Nancy; Ma, Yue; Chang, Lei; Zhou, Qing; West, Stephen G.; Aiken, Leona
2006-01-01
The purpose of the study was to examine the zero-order and unique relations of effortful attentional and behavioral regulation, reactive impulsivity, and anger/frustration to Chinese first and second graders’ internalizing and externalizing symptoms, as well as the prediction of adjustment from the interaction of anger/frustration and effortful control or impulsivity. A parent and teacher reported on children’s anger/frustration, effortful control, and impulsivity; parents reported on children’s internalizing symptoms; and teachers and peers reported on children’s externalizing symptoms. Children were classified as relatively high on externalizing (or comorbid), internalizing, or nondisordered. High impulsivity and teacher-reported anger/frustration, and low effortful control, were associated with externalizing problems whereas low effortful control and high parent-reported anger were predictive of internalizing problems. Unique prediction from effortful and reactive control was obtained and these predictors (especially when reported by teachers) often interacted with anger/frustration when predicting problem behavior classification. PMID:17459176
Design of an fMRI-compatible optical touch stripe based on frustrated total internal reflection.
Jarrahi, Behnaz; Wanek, Johann
2014-01-01
Previously we developed a low-cost, multi-configurable handheld response system, using a reflective-type intensity modulated fiber-optic sensor (FOS) to accurately gather participants' behavioral responses during functional magnetic resonance imaging (fMRI). Inspired by the popularity and omnipresence of the fingertip-based touch sensing user interface devices, in this paper we present the design of a prototype fMRI-compatible optical touch stripe (OTS) as an alternative configuration. The prototype device takes advantage of a proven frustrated total internal reflection (FTIR) technique. By using a custom-built wedge-shaped optically transparent acrylic prism as an optical waveguide, and a plano-concave lens to provide the required light beam profile, the position of a fingertip touching the surface of the wedge prism can be determined from the deflected light beams that become trapped within the prism by total internal reflection. To achieve maximum sensitivity, the optical design of the wedge prism and lens were optimized through a series of light beam simulations using WinLens 3D Basic software suite. Furthermore, OTS performance and MRI-compatibility were assessed on a 3.0 Tesla MRI scanner running echo planar imaging (EPI) sequences. The results show that the OTS can detect a touch signal at high spatial resolution (about 0.5 cm), and is well suited for use within the MRI environment with average time-variant signal-to-noise ratio (tSNR) loss < 3%.
NASA Astrophysics Data System (ADS)
Hull, J. R.
Since its introduction, the concept of nonimaging solar concentrators, as exemplified by the compound parabolic concentrator (CPC) design, has greatly enhanced the ability to collect solar energy efficiently in thermal and photovoltaic devices. When used as a primary concentrator, a CPC can provide significant concentration without the complication of a tracking mechanism and its associated maintenance problems. When used as a secondary, a CPC provides higher total concentration, or for a fixed concentration, tolerates greater tracking error in the primary.
Ko, Chih-Hung; Yen, Ju-Yu; Yen, Cheng-Fang; Chen, Chung-Sheng; Wang, Shing-Yaw
2008-06-01
This study evaluated the association between Internet addiction and frustration intolerance, the gender difference of frustration intolerance, and the gender differences of the association between Internet addiction and frustration intolerance. Participants were 2,114 students (1,204 male and 910 female) who were recruited to complete the Chen Internet Addiction Scale and Frustration Discomfort scale. Females had higher scores on the subscale of entitlement and emotional intolerance and the total scale of the frustration intolerance. There was a significant gender difference on the association between Internet addiction and frustration intolerance. The association was higher in male adolescents. Regression analysis revealed male adolescents with Internet addiction had higher intolerance to frustration of entitlement and emotional discomfort, and female adolescents with it had higher intolerance to emotional discomfort and lower tolerance to frustration of achievement. Frustration intolerance should be evaluated for adolescents with Internet addiction, especially for males. Rational emotive behavior therapy focusing on different irrational beliefs should be provided to male and female adolescents with Internet addiction.
Muhtadie, Luma; Zhou, Qing; Eisenberg, Nancy; Wang, Yun
2013-08-01
The additive and interactive relations of parenting styles (authoritative and authoritarian parenting) and child temperament (anger/frustration, sadness, and effortful control) to children's internalizing problems were examined in a 3.8-year longitudinal study of 425 Chinese children (aged 6-9 years) from Beijing. At Wave 1, parents self-reported on their parenting styles, and parents and teachers rated child temperament. At Wave 2, parents, teachers, and children rated children's internalizing problems. Structural equation modeling indicated that the main effect of authoritative parenting and the interactions of Authoritarian Parenting × Effortful Control and Authoritative Parenting × Anger/Frustration (parents' reports only) prospectively and uniquely predicted internalizing problems. The above results did not vary by child sex and remained significant after controlling for co-occurring externalizing problems. These findings suggest that (a) children with low effortful control may be particularly susceptible to the adverse effect of authoritarian parenting and (b) the benefit of authoritative parenting may be especially important for children with high anger/frustration.
A toy model for hostility between two populations in dependency on their internal frustration
NASA Astrophysics Data System (ADS)
Wieder, Thomas
2014-10-01
Hostility between two populations n and m is described in terms of a first-order differential equation system for the population sizes n(t) and m(t) over time t. Each population is subdivided into two subpopulations 'Doves' and 'Hawks'. Hawks represent the strategy aggression against the other population. The number of hawks which actually exert aggression depends on the overall frustration within their population. Conversely, aggression causes the conversion from doves to hawks in the attacked population. Thus, a system of flows among the subpopulation is established. The actual behaviour of n(t) and m(t) over time t depends on the coefficients chosen for the differential system and in particular on the temporal development of the frustration parameters. No calculation or simulation of actual population sizes is intended. The only goal of the paper is to establish a model which describes an never ending conflict between both populations caused by internal frustrations.
Muhtadie, Luma; Zhou, Qing; Eisenberg, Nancy; Wang, Yun
2012-01-01
The additive and interactive relations of parenting styles (authoritative and authoritarian parenting) and child temperament (anger/frustration, sadness, and effortful control) to children’s internalizing problems were examined in a 3.8-year longitudinal study of 425 Chinese children (6 – 9 years) from Beijing. At Wave 1, parents self-reported on their parenting styles, and parents and teachers rated child temperament. At Wave 2, parents, teachers, and children rated children’s internalizing problems. Structural equation modeling indicated that the main effect of authoritative parenting, and the interactions of authoritarian parenting × effortful control and authoritative parenting × anger/frustration (parents’ reports only) prospectively and uniquely predicted internalizing problems. The above results did not vary by child sex and remained significant after controlling for co-occurring externalizing problems. These findings suggest that: a) children with low effortful control may be particularly susceptible to the adverse effect of authoritarian parenting, and b) the benefit of authoritative parenting may be especially important for children with high anger/frustration. PMID:23880383
Accessible biometrics: A frustrated total internal reflection approach to imaging fingerprints.
Smith, Nathan D; Sharp, James S
2017-05-01
Fingerprints are widely used as a means of identifying persons of interest because of the highly individual nature of the spatial distribution and types of features (or minuta) found on the surface of a finger. This individuality has led to their wide application in the comparison of fingerprints found at crime scenes with those taken from known offenders and suspects in custody. However, despite recent advances in machine vision technology and image processing techniques, fingerprint evidence is still widely being collected using outdated practices involving ink and paper - a process that can be both time consuming and expensive. Reduction of forensic service budgets increasingly requires that evidence be gathered and processed more rapidly and efficiently. However, many of the existing digital fingerprint acquisition devices have proven too expensive to roll out on a large scale. As a result new, low-cost imaging technologies are required to increase the quality and throughput of the processing of fingerprint evidence. Here we describe an inexpensive approach to digital fingerprint acquisition that is based upon frustrated total internal reflection imaging. The quality and resolution of the images produced are shown to be as good as those currently acquired using ink and paper based methods. The same imaging technique is also shown to be capable of imaging powdered fingerprints that have been lifted from a crime scene using adhesive tape or gel lifters. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.
The Hazards of Growing up: A Study of the Changing Mechanisms of Bullying among Girls in Shenzhen
ERIC Educational Resources Information Center
Tam, Frank Wai-ming; Zhang, Sophia Zhao-qin
2012-01-01
Among the many contending theories of bullying, the widely accepted thesis known as "frustration-aggression" assumes that bullying is a form of aggressive behavior induced by external stress. Recently, researchers have discovered that the relationship between external stressors and bullying is sometimes moderated by internal frustration.…
Air gap resonant tunneling bandpass filter and polarizer.
Melnyk, A; Bitarafan, M H; Allen, T W; DeCorby, R G
2016-04-15
We describe a bandpass filter based on resonant tunneling through an air layer in the frustrated total internal reflection regime, and show that the concept of induced transmission can be applied to the design of thin film matching stacks. Experimental results are reported for Si/SiO2-based devices exhibiting a polarization-dependent passband, with bandwidth on the order of 10 nm in the 1550 nm wavelength range, peak transmittance on the order of 80%, and optical density greater than 5 over most of the near infrared region.
ERIC Educational Resources Information Center
Csapo, Marg
1991-01-01
This evaluation of 16 children (ages 7-12) with achondroplasia from Transkei, Hungary, and Nigeria found that, compared to controls, subjects had more behavior problems and less self-esteem. Subjects were socially withdrawn, internalized emotional problems, had lower academic performance, found less adaptive solutions to frustration, and faced…
PREFACE: The International Conference on Highly Frustrated Magnetism HFM2008
NASA Astrophysics Data System (ADS)
Eremin, Ilya; Brenig, Wolfram; Kremer, Reinhard; Litterst, Jochen
2009-01-01
The International Conference on Highly Frustrated Magnetism 2008 (HFM2008) took place on 7-12 September 2008 at the Technische Universität Carolo-Wilhelmina zu Braunschweig, Germany. This conference was the fourth event in a series of meetings, which started in Waterloo, Canada (HFM 2000), followed by the second one in Grenoble, France (HFM 2003), and the third meeting in Osaka, Japan (HFM 2006). HFM2008 attracted more than 220 participants from all over the world. The number of participants of the HFM conference series has been increasing steadily, from about 80 participants at HFM 2000, to 120 participants at HFM 2003, and 190 participants at HFM 2006, demonstrating that highly frustrated magnetism remains a rapidly growing area of research in condensed matter physics. At the end of HFM2008 it was decided that the next International Conference on Highly Frustrated Magnetism will be held in Baltimore, USA in 2010. HFM2008 saw four plenary talks by R Moessner, S Nakatsuji, S-W Cheong, and S Sachdev, 18 invited presentations, 30 contributed talks and about 160 poster presentations from all areas of frustrated magnetism. The subjects covered by the conference included: Kagome systems Itinerant frustrated systems Spinels and pyrochlore materials Triangular systems Unconventional order and spin liquids Chain systems Chain systems Novel frustrated systems This volume of Journal of Physics: Conference Series contains the proceedings of HFM2008 with 83 papers that provide a scientific record of the scientific topics covered by the conference. All articles have been refereed by experts in the field. It is our hope that the reader will enjoy and profit from the HFM2008 Proceedings. Ilya Eremin Proceedings Editor Wolfram Brenig, Reinhard Kremer, and Jochen Litterst Co-Editors International Advisory Board L Balents (USA) F Becca (Italy) S Bramwell (UK) P Fulde (Germany) B D Gaulin (Canada) J E Greedan (Canada) A Harrison (France) Z Hiroi (Japan) H Kawamura (Japan) A Keren (Israel) C Lacroix (France) C Lhuillier (France) A Loidl (Germany) G Misguich (France) J Richter (Germany) A M Olés (Poland) P Schiffer (USA) R Stern (Estonia) O Tchernyshyov (USA) M R. Valenti (Germany) G Zwicknagl (Germany) International Program Committee W Brenig (Germany) C Broholm (USA) M Gingras (Canada) K Ueda (Japan) P Mendels (France) F Mila (Switzerland) R Moessner (Germany) Conference photograph On behalf of the HFM2008 Organizing Committee, I wish to express my sincere thanks to everyone who supported us in organizing and setting up HFM2008. Especially, I would like to thank the European Science Foundation and the Max-Planck-Institut für Festkörperforschung for the generous financial support, the Technische Universität Braunschweig and the City of Braunschweig for hosting the conference, all colleagues who served on the Advisory and Program Board, the Referees, and last but not least, the staff members from Stuttgart and Braunschweig, Mrs Gisela Siegle, Mrs Regine Noack and Mrs Katharina Schnettler, for their helpful and invaluable assistance. Reinhard Kremer
Work-related frustration among senior nurses at a medical centre.
Wang, Pei-Hern; Ku, Yan-Chiou; Chen, Chi-Chi; Jeang, Shiow-Rong; Chou, Frank Huang-Chih
2016-07-01
To investigate the levels and causes of work-related frustration among senior nurses. Role changes and the associated expectations and setbacks faced by senior middle-aged nurses can easily result in low morale. Therefore, working setbacks experienced by senior nurses must be investigated. A cross-sectional questionnaire study. Purposive sampling was used to select questionnaire recipients. In total, 482 senior nurses completed and returned a structured questionnaire. The predictive factors for frustration at work among senior nurses included age, service unit, and the impact of sleep disorders, which jointly explained 54% of the variance. In particular, age and service unit were important predictive factors for frustration at work. Senior nurses had medium-to-low scores for frustration at work and did not perceive a high level of frustration. The outpatient departments and other medical departments in this sector should provide a reasonable system of incentives and promotion opportunities if they are to retain their most senior and experienced nurses. The results of this study could serve as a reference for hospital administrations. © 2016 John Wiley & Sons Ltd.
Review of infrared scene projector technology-1993
NASA Astrophysics Data System (ADS)
Driggers, Ronald G.; Barnard, Kenneth J.; Burroughs, E. E.; Deep, Raymond G.; Williams, Owen M.
1994-07-01
The importance of testing IR imagers and missile seekers with realistic IR scenes warrants a review of the current technologies used in dynamic infrared scene projection. These technologies include resistive arrays, deformable mirror arrays, mirror membrane devices, liquid crystal light valves, laser writers, laser diode arrays, and CRTs. Other methods include frustrated total internal reflection, thermoelectric devices, galvanic cells, Bly cells, and vanadium dioxide. A description of each technology is presented along with a discussion of their relative benefits and disadvantages. The current state of each methodology is also summarized. Finally, the methods are compared and contrasted in terms of their performance parameters.
A study of muscular tissue of animal origin by reflection-spectroscopy methods
NASA Astrophysics Data System (ADS)
Plotnikova, L. V.; Nechiporenko, A. P.; Orekhova, S. M.; Plotnikov, P. P.; Ishevskii, A. L.
2017-06-01
A comparative analysis of the spectral characteristics of the surface of muscular tissue of animal origin (pork) and its main components has been performed by the methods of diffuse reflection electronic spectroscopy (DRES) and frustrated total internal reflection IR spectroscopy. The experiments have shown that the application of the DRES method makes it possible to detect more pronounced changes in the surface optical characteristics of muscular tissue and obtain electronic spectra containing information about the component composition of its main parts under successive extraction of sarcoplasmic materials, myofibrillar proteins of the actomyosin complex, and stroma mucopolysaccharides.
Ormel, J; Oldehinkel, A J; Ferdinand, R F; Hartman, C A; De Winter, A F; Veenstra, R; Vollebergh, W; Minderaa, R B; Buitelaar, J K; Verhulst, F C
2005-12-01
We investigated the links between familial loading, preadolescent temperament, and internalizing and externalizing problems in adolescence, hereby distinguishing effects on maladjustment in general versus dimension-specific effects on either internalizing or externalizing problems. In a population-based sample of 2230 preadolescents (10-11 years) familial loading (parental lifetime psychopathology) and offspring temperament were assessed at baseline by parent report, and offspring psychopathology at 2.5-years follow-up by self-report, teacher report and parent report. We used purified measures of temperament and psychopathology and partialled out shared variance between internalizing and externalizing problems. Familial loading of internalizing psychopathology predicted offspring internalizing but not externalizing problems, whereas familial loading of externalizing psychopathology predicted offspring externalizing but not internalizing problems. Both familial loadings were associated with Frustration, low Effortful Control, and Fear. Frustration acted as a general risk factor predicting severity of maladjustment; low Effortful Control and Fear acted as dimension-specific risk factors that predicted a particular type of psychopathology; whereas Shyness, High-Intensity Pleasure, and Affiliation acted as direction markers that steered the conditional probability of internalizing versus externalizing problems, in the event of maladjustment. Temperament traits mediated one-third of the association between familial loading and psychopathology. Findings were robust across different composite measures of psychopathology, and applied to girls as well as boys. With regard to familial loading and temperament, it is important to distinguish general risk factors (Frustration) from dimension-specific risk factors (familial loadings, Effortful Control, Fear), and direction markers that act as pathoplastic factors (Shyness, High-Intensity Pleasure, Affiliation) from both types of risk factors. About one-third of familial loading effects on psychopathology in early adolescence are mediated by temperament.
Perceived levels of frustration during clinical situations in athletic training students.
Heinerichs, Scott; Curtis, Neil; Gardiner-Shires, Alison
2014-01-01
Athletic training students (ATSs) are involved in various situations during the clinical experience that may cause them to express levels of frustration. Understanding levels of frustration in ATSs is important because frustration can affect student learning, and the clinical experience is critical to their development as professionals. To explore perceived levels of frustration in ATSs during clinical situations and to determine if those perceptions differ based on sex. Cross-sectional study with a survey instrument. A total of 14 of 19 professional, undergraduate athletic training programs accredited by the Commission on Accreditation of Athletic Training Education in Pennsylvania. Of a possible 438 athletic training students, 318 (72.6%) completed the survey. The Athletic Training Student Frustration Inventory was developed and administered. The survey gathered demographic information and included 24 Likert-scale items centering on situations associated with the clinical experience. Descriptive statistics were computed on all items. The Mann-Whitney U was used to evaluate differences between male and female students. A higher level of frustration was perceived during the following clinical situations: lack of respect by student-athletes and coaching staffs, the demands of the clinical experience, inability of ATSs to perform or remember skills, and ATSs not having the opportunity to apply their skills daily. Higher levels of frustration were perceived in female than male ATSs in several areas. Understanding student frustration during clinical situations is important to better appreciate the clinical education experience. Low levels of this emotion are expected; however, when higher levels exist, learning can be affected. Whereas we cannot eliminate student frustrations, athletic training programs and preceptors need to be aware of this emotion in order to create an environment that is more conducive to learning.
NASA Astrophysics Data System (ADS)
Giampaolo, S. M.; Hiesmayr, B. C.; Illuminati, F.
2015-10-01
Frustration in quantum many-body systems is quantified by the degree of incompatibility between the local and global orders associated, respectively, with the ground states of the local interaction terms and the global ground state of the total many-body Hamiltonian. This universal measure is bounded from below by the ground-state bipartite block entanglement. For many-body Hamiltonians that are sums of two-body interaction terms, a further inequality relates quantum frustration to the pairwise entanglement between the constituents of the local interaction terms. This additional bound is a consequence of the limits imposed by monogamy on entanglement shareability. We investigate the behavior of local pair frustration in quantum spin models with competing interactions on different length scales and show that valence bond solids associated with exact ground state dimerization correspond to a transition from generic frustration, i.e., geometric, common to classical and quantum systems alike, to genuine quantum frustration, i.e., solely due to the noncommutativity of the different local interaction terms. We discuss how such frustration transitions separating genuinely quantum orders from classical-like ones are detected by observable quantities such as the static structure factor and the interferometric visibility.
A Gateway to Integration: A Study of American Families and Their International Visitors
ERIC Educational Resources Information Center
Hellmann, Kate; Miyazaki, Rachel; Miranda, Daniela; Fiscus, Tricia
2016-01-01
Research shows that helping international students build support networks by forming new friendships is crucial to counteracting the feelings of isolation, loneliness, and frustration that may arise from studying abroad. Studies have shown that friendships between international students and host nationals benefit the local community rather than…
Fingertip-shaped optical tactile sensor for robotic applications
NASA Technical Reports Server (NTRS)
Begej, Stefan
1988-01-01
Progress is described regarding the development of a high-density, fiber-optic, fingertip-shaped tactile sensor specifically designed for application to dexterous robotics. The sensor operates on optical principles involving the frustration of total internal reflection at a waveguide/elastomer interface and generates a grey-scale tactile image that represents the normal forces of contact. The sensor contains 256 taxels (sensing sites) distributed in a dual-density pattern that includes a tactile fovea near the tip which measures 13 mm x 13 mm and contains 169 taxels. The details regarding the design and construction of this tactile sensor are presented, in addition to photographs of tactile imprints.
The 8th International Conference on Highly Frustrated Magnetism (HFM 2016)
NASA Astrophysics Data System (ADS)
Gardner, J. S.; Kao, Y. J.
2017-04-01
The 8th International Conference on Highly Frustrated Magnetism 2016 (HFM 2016) took place between the 7th and 11th of September 2016 at the GIS Convention Center at National Taiwan University, Taipei, Taiwan. Over 260 participants from all over the world, attended the meeting making it the largest HFM to-date and revealing the impressive growth in the community since the original meeting in Waterloo, Canada where 80 participants attended. Preceding the meeting a school was held at the National Synchrotron Radiation Research Center to help those new to the field understand the material they were likely to see at HFM2016. Our thanks to the international speakers who attended this school John Chalker, Michel Kenzelmann, Philippe Mendels, Luigi Paolasini, Kirrily Rule, Yixi Su, Isao Watanabe and those from Taiwan W. T. Chen, Y-J, Kao, L. J. Chang and C. S. Ku, for their enlightening presentations. The HFM 2016 conference consisted of five plenary talks by H Takagi, B D Gaulin, L Balents, Y Tokura and S T Bramwell, 20 invited and 40 contributed presentations, and about 160 poster presentations from all aspects of theoretical and experimental frustrated magnetism. During the conference period, many stimulating discussions were held both inside and outside the conference room. Excursions to Taipei 101 and the National Palace Museum, as well as several organized dinners and receptions allowed the participants to initiate collaborations and discuss the hottest issues. The subjects covered in the conference included: · Quantum frustrated magnetism and spin liquids · Novel ordering of geometrically frustrated magnets · Frustration effect on the coupling to lattice, orbital and charge degrees of freedom · Exotic phenomena induced by macroscopic degeneracy · Field effect on frustrated magnetism etc. These proceeding represent a very small, but valuable contribution to the community. I hope you enjoy reading them. In view of the rapid growth of the field, it has been decided at the conference that the next HFM conference will be held in two years, in 2018, on the campus of UC Davis, followed one in Shanghai around December 2019. Finally, on behalf of the HFM 2016 Organizing Committee, I wish to deeply thank all the people who generously helped us in organizing and running the HFM 2016 conference. These include the numerous funding sources, Committee Members, Program and Session chairs, Chia-Chi Liu, Chao-Jung Kuo, Hanz Peng, Laura Bravo and Stella Su and of course all the participants, without you it would have simply been another wet week in Taipei. One might remember HFM2016 for the power outage, but we hope you remember the taste, sounds and views of Taipei as well as stimulation conversations and hopefully the beginnings of productive partnerships.
Perceived Levels of Frustration During Clinical Situations in Athletic Training Students
Heinerichs, Scott; Curtis, Neil; Gardiner-Shires, Alison
2014-01-01
Context: Athletic training students (ATSs) are involved in various situations during the clinical experience that may cause them to express levels of frustration. Understanding levels of frustration in ATSs is important because frustration can affect student learning, and the clinical experience is critical to their development as professionals. Objective: To explore perceived levels of frustration in ATSs during clinical situations and to determine if those perceptions differ based on sex. Design: Cross-sectional study with a survey instrument. Setting: A total of 14 of 19 professional, undergraduate athletic training programs accredited by the Commission on Accreditation of Athletic Training Education in Pennsylvania. Patients or Other Participants: Of a possible 438 athletic training students, 318 (72.6%) completed the survey. Main Outcomes Measure(s): The Athletic Training Student Frustration Inventory was developed and administered. The survey gathered demographic information and included 24 Likert-scale items centering on situations associated with the clinical experience. Descriptive statistics were computed on all items. The Mann-Whitney U was used to evaluate differences between male and female students. Results: A higher level of frustration was perceived during the following clinical situations: lack of respect by student-athletes and coaching staffs, the demands of the clinical experience, inability of ATSs to perform or remember skills, and ATSs not having the opportunity to apply their skills daily. Higher levels of frustration were perceived in female than male ATSs in several areas. Conclusions: Understanding student frustration during clinical situations is important to better appreciate the clinical education experience. Low levels of this emotion are expected; however, when higher levels exist, learning can be affected. Whereas we cannot eliminate student frustrations, athletic training programs and preceptors need to be aware of this emotion in order to create an environment that is more conducive to learning. PMID:24143904
ERIC Educational Resources Information Center
Yin, Lishu
2013-01-01
The number of international students flocking to North American private Christian schools has continued to grow. The author examined the overall experiences of 67 international high school students studying at a private Christian school in South Carolina. Their frustrations and struggles with academic and spiritual growth in a new cross-cultural…
ERIC Educational Resources Information Center
Shafaei, Azadeh; Nejati, Mehran; Quazi, Ali; von der Heidt, Tania
2016-01-01
International students undertaking higher education in foreign countries bring with them some perceived beliefs about academic conduct. These beliefs are often in contrast with the host countries' academic practices, which may generate confusion and frustration among international students, affecting their learning behaviours. As a consequence of…
ERIC Educational Resources Information Center
Levenson, Lauren Nicole
2017-01-01
The purpose of this study was to examine the relationship between parent-child relationship characteristics (attachment, involvement, discipline practices, parenting confidence, and relational frustration) and behavioral outcomes (internalizing, externalizing, and adaptive) in children with autism spectrum disorder (ASD). ASD presents pervasive…
Industrial relations: workings of the maintenance strike.
Davidson, N
1978-11-10
The frustrations leading to the maintenance dispute go back four years. Author highlights the NHS's inability to handle internal disagreements, and the problems of a bureaucratic and politically-directed profession.
ERIC Educational Resources Information Center
Gollin, George D.
2009-01-01
The global demand for higher education currently exceeds the world's existing university capacity. This shortfall is likely to persist for the foreseeable future, raising concerns that frustrated students might choose to purchase fraudulent credentials from counterfeiters or diploma mills. International efforts to encourage the development of…
Fournier, Frédéric; Zheng, Wanquan; Carrez, Serge; Dubost, Henri; Bourguignon, Bernard
2004-09-08
Interaction of CO adsorbed on Pt(111) with electrons and phonons is studied experimentally by means of a pump-probe experiment where CO is probed by IR + visible sum frequency generation under a pump laser intensity that allows photodesorption. Vibrational spectra of CO internal stretch are obtained as a function of pump-probe delay. A two-temperature and anharmonic coupling model is used to extract from the spectra the real time variations of CO peak frequency and dephasing time. The main conclusions are the following: (i) The CO stretch is perturbed by two low-frequency modes, assigned to frustrated rotation and frustrated translation. (ii) The frustrated rotation is directly coupled to electrons photoexcited in Pt(111) by the pump laser. (iii) There is no evidence of Pt-CO stretch excitation in the spectra. The implications for the photodesorption dynamics are discussed. Copyright 2004 American Institute of Physics
NASA Astrophysics Data System (ADS)
Fournier, Frédéric; Zheng, Wanquan; Carrez, Serge; Dubost, Henri; Bourguignon, Bernard
2004-09-01
Interaction of CO adsorbed on Pt(111) with electrons and phonons is studied experimentally by means of a pump-probe experiment where CO is probed by IR+visible sum frequency generation under a pump laser intensity that allows photodesorption. Vibrational spectra of CO internal stretch are obtained as a function of pump-probe delay. A two-temperature and anharmonic coupling model is used to extract from the spectra the real time variations of CO peak frequency and dephasing time. The main conclusions are the following: (i) The CO stretch is perturbed by two low-frequency modes, assigned to frustrated rotation and frustrated translation. (ii) The frustrated rotation is directly coupled to electrons photoexcited in Pt(111) by the pump laser. (iii) There is no evidence of Pt-CO stretch excitation in the spectra. The implications for the photodesorption dynamics are discussed.
Frustration-induced internal stresses are responsible for quasilocalized modes in structural glasses
NASA Astrophysics Data System (ADS)
Lerner, Edan; Bouchbinder, Eran
2018-03-01
It has been recently shown [E. Lerner, G. Düring, and E. Bouchbinder, Phys. Rev. Lett. 117, 035501 (2016), 10.1103/PhysRevLett.117.035501] that the nonphononic vibrational modes of structural glasses at low frequencies ω are quasilocalized and follow a universal density of states D (ω ) ˜ω4 . Here we show that the gapless nature of the observed density of states depends on the existence of internal stresses that generically emerge in glasses due to frustration, thus elucidating a basic element underlying this universal behavior. Similarly to jammed particulate packings, low-frequency modes in structural glasses emerge from a balance between a local elasticity term and an internal stress term in the dynamical matrix, where the difference between them is orders of magnitude smaller than their typical magnitude. By artificially reducing the magnitude of internal stresses in a computer glass former in three dimensions, we show that a gap is formed in the density of states below which no vibrational modes exist, thus demonstrating the crucial importance of internal stresses. Finally, we show that while better annealing the glass upon cooling from the liquid state significantly reduces its internal stresses, the self-organizational processes during cooling render the gapless D (ω ) ˜ω4 density of state unaffected.
Study of a coronagraphic mask using evanescent waves.
Buisset, Christophe; Rabbia, Yves; Lepine, Thierry; Alagao, Mary-Angelie; Ducrot, Elsa; Poshyachinda, Saran; Soonthornthum, Boonrucksar
2017-04-03
The evanescent wave coronagraph (EvWaCo) is a specific kind of band-limited coronagraph using the frustrated total internal reflection phenomenon to produce the coronagraphic effect (removing starlight from the image plane in order to make the stellar environment detectable). In this paper, we present a theoretical and experimental study of the EvWaCo coronagraphic mask. First, we calculate the theoretical transmission and we show that this mask is partially achromatic. Then, we present the experimental results obtained in unpolarized light at the wavelength λ≈900 nm and relative spectral bandwidth Δλ/λ≈6%. In particular, we show that the coronagraph provides a contrast down to a few 10-6 at an angular distance of about ten Airy radii.
Azzam, R M A; De, A
2003-03-01
A symmetric achiral trilayer structure, which consists of a high-index center layer sandwiched between two identical low-index films and embedded in a high-index prism, is designed to produce equal and opposite quarter-wave retardation in reflection and transmission and equal throughput for the p and s polarization at oblique incidence. Such a device splits a beam of incident linearly polarized light into two orthogonally circularly polarized components of equal power that travel in different directions. A visible (633-nm) design that operates at a 60 degree angle of incidence and an infrared (10.6-microm) 45 degree cube design are presented. The spectral and angular sensitivities of the device are also considered.
NASA Astrophysics Data System (ADS)
Fofanov, Ya A.
2009-06-01
A series of reflection resonances formed by the hyperfine components of the D2-lines in the spectrum of the natural mixture of rubidium isotopes is studied. Passages from resonantly frustrated total internal reflection to resonance Brewster reflection caused by the frequency tuning of the incident light are demonstrated experimentally. The contrast of the strongest refection resonances exceeds 500% at the moderate heating of reflecting cells. The intensity of the reflected light changes in this case by more than 20 times. A theory is developed which is based on a two-level model for resonance atoms and Fresnel formulas for reflection coefficients. Numerical calculations based on the proposed theory confirm main experimental results.
[French validation of the Frustration Discomfort Scale].
Chamayou, J-L; Tsenova, V; Gonthier, C; Blatier, C; Yahyaoui, A
2016-08-01
Rational emotive behavior therapy originally considered the concept of frustration intolerance in relation to different beliefs or cognitive patterns. Psychological disorders or, to some extent, certain affects such as frustration could result from irrational beliefs. Initially regarded as a unidimensional construct, recent literature considers those irrational beliefs as a multidimensional construct; such is the case for the phenomenon of frustration. In order to measure frustration intolerance, Harrington (2005) developed and validated the Frustration Discomfort Scale. The scale includes four dimensions of beliefs: emotional intolerance includes beliefs according to which emotional distress is intolerable and must be controlled or avoided as soon as possible. The intolerance of discomfort or demand for comfort is the second dimension based on beliefs that life should be peaceful and comfortable and that any inconvenience, effort or hassle should be avoided. The third dimension is entitlement, which includes beliefs about personal goals, such as merit, fairness, respect and gratification, and that others must not frustrate those non-negotiable desires. The fourth dimension is achievement, which reflects demands for high expectations or standards. The aim of this study was to translate and validate in a French population the Frustration and Discomfort Scale developed by Harrington (2005), assess its psychometric properties, highlight the four factors structure of the scale, and examine the relationships between this concept and both emotion regulation and perceived stress. We translated the Frustration Discomfort Scale from English to French and back from French to English in order to ensure good quality of translation. We then submitted the scale to 289 students (239 females and 50 males) from the University of Savoy in addition to the Cognitive Emotional Regulation Questionnaire and the Perceived Stress Scale. The results showed satisfactory psychometric qualities. After removing five items from the original scale, the internal consistency appeared satisfactory for both the full scale (α=0.86), and the four sub-dimensions, with alphas ranging from 0.64 to 0.71. Although these values are lower than those from the original tool (Harrington, 2005), they are very close to the validation data in other languages (Ozer et al., 2012). Interestingly, the FDS score was related to the Perceived Stress Scale and non-adaptive emotion regulation factor but not to the adaptive emotion regulation factor. However, the factorial analyses do not unambiguously support the original four factors structure proposed by Harrington (2005). Reliability as well as convergent and divergent validity indicate that the French version of the Frustration Discomfort Scale is a relevant measure of frustration intolerance. However, divergent validity has not been completely demonstrated. The validation data is more congruent with a one-dimensional factor structure than with the original four-dimensional structure. Frustration intolerance could therefore be understood as a unitary concept. Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.
[Concept of external reality in Freud's works].
Dorfman Lerner, B
1981-07-01
Three main functions of external reality (E.R.) relative to the subjecto may be mentioned. a) it is a source of stimulae that promote the structuring of te psychic apparatus. In this sense, E.F. is the place where this apparatus is charged and where it is discharged (specific action). b) it is a vehicle of gratification or frustration of necessity (Anaké). The satisfaction of necessity is gratifying, the lackof it is frustrating. c) it is the instance that heals or makes a person ill acording to its possibility of gratifying or frustrating the subject respectively. If we first take point a), we can examine the relationship between E.R. and internal (psychic) reality along the process of internalization of normal and pathologic experience. The author thinks Freud considers frustration as structuring of the psychic apparatus as long as it does not satisfy the person's needs or opposes the accomplishment of his desire. This complels the subject to recognize the existence of the external object. Also, whenfacing the external object the subject discovers his own self. Coinciding with this reognitions he tries to defend himself against it. In normal circustances the image of the external world is built by means of successive projections and introjections. The more sane the subject, the more faithfully and without distortions will he incorporate the external images. To be structuring, the frustrations must be encountered in adequate dose. If it is excessive there will be a distortion of the image due not only to projection but also to the defusion of instincts (defusion that takes place in the process of introjection of external figures). These distorted images of the external world coexist with various fantsies. But these fantasies are also marked by E.R. Even when the individual history of a subject does not give accont of this reality, there is a "filogenetic endowment" of fantasies that always recognize an external origin: they are the prehistoric fantasies. This hypothesis of the original fantasies is similar, in respect to their ontogenetic origin, to the innate ideas of Descartes and it is coherent with Freud's empirical point of view of those fantasies being perceptions in a filogenetic past. In this way Freud tries to give account both of the idealistic and the empiricist points of view about perception. If in genetic matters the interaction with the external world is primordial, in epigenetic matters Freud goes away from empericism of perception to propose the hypothesis of an internal reality, that differs from empericism of perception to propose the hypothesis of an internal reality, that differs from external material reality. But even in the psychotic process, in which the psychological reality is far apart from E.R., the former gets influenced by the latter...
Interpersonal motives in anorexia nervosa: the fear of losing one's autonomy.
Brockmeyer, Timo; Holtforth, Martin Grosse; Bents, Hinrich; Kämmerer, Annette; Herzog, Wolfgang; Friederich, Hans-Christoph
2013-03-01
This study examined the widely held but insufficiently studied hypothesis of autonomy disturbances in anorexia nervosa. A total sample of 112 participants comprising patients with acute anorexia nervosa (AN), women recovered from anorexia nervosa (REC), clinical controls (CC), and healthy controls (HC) completed measures of dependency and intimacy strivings, as well as measures of frustrations of these same strivings. In comparison to HC and CC, AN showed a stronger motivation to avoid dependency and lower strivings for intimacy. Compared with HC, but not with CC, AN also showed stronger frustrations of the same motives. Whereas REC did not differ from AN regarding avoidance of dependency, they reported lower frustration of dependency avoidance (i.e., less actual experiences of dependency). Finally, REC reported higher intimacy motivation as well as better satisfaction of intimacy motivation as compared with AN. The present findings suggest that a pronounced motive of avoiding dependency may be a vulnerability factor for anorexia nervosa that is disorder-specific and trait-like. Frustrations of this motive seem to be associated with psychopathology. © 2012 Wiley Periodicals, Inc.
Homma, Mieko; Ishikawa, Hirono; Kiuchi, Takahiro
2016-04-01
The aim of this study was to elucidate whether physicians' illness perceptions correlate with their frustration or resistance to accepting patients with fibromyalgia (FM). In this cross-sectional postal survey, questionnaires were sent to member physicians of the Japan College of Rheumatology and Japan Rheumatism Foundation. Measures collected included the Brief Illness Perception Questionnaire with Causal Attribution, the Illness Invalidation Inventory, and the Difficult Doctor-Patient Relationship Questionnaire (DDPRQ-10). Multiple logistic regression was performed to examine associations between the DDPRQ-10 and resistance to accepting patients with FM for treatment. We analyzed data from 233 physicians who had experience in consulting with patients with FM. Only 44.2 % answered that they wanted to accept additional patients with FM. Physicians' frustration was associated with difficulty controlling symptoms, patients' emotional responses, and causal attribution of FM to patient internal factors. Conversely, lower levels of frustration were associated with causal attributions to biological factors and uncontrollable external factors. However, the "difficult patient" perception did not correlate with resistance to accepting patients with FM. Difficulty controlling symptoms with treatment was the one factor common to both physicians' frustration and resistance to accepting patients with FM. Physicians may hesitate to accept patients with FM not because of the stigmatic image of the "difficult patient," but instead because of the difficulty in controlling the symptoms of FM. Thus, to improve the quality of consultation, physicians must continuously receive new information about the treatments and causes of FM.
Impact of Frequent Interruption on Nurses' Patient-Controlled Analgesia Programming Performance.
Campoe, Kristi R; Giuliano, Karen K
2017-12-01
The purpose was to add to the body of knowledge regarding the impact of interruption on acute care nurses' cognitive workload, total task completion times, nurse frustration, and medication administration error while programming a patient-controlled analgesia (PCA) pump. Data support that the severity of medication administration error increases with the number of interruptions, which is especially critical during the administration of high-risk medications. Bar code technology, interruption-free zones, and medication safety vests have been shown to decrease administration-related errors. However, there are few published data regarding the impact of number of interruptions on nurses' clinical performance during PCA programming. Nine acute care nurses completed three PCA pump programming tasks in a simulation laboratory. Programming tasks were completed under three conditions where the number of interruptions varied between two, four, and six. Outcome measures included cognitive workload (six NASA Task Load Index [NASA-TLX] subscales), total task completion time (seconds), nurse frustration (NASA-TLX Subscale 6), and PCA medication administration error (incorrect final programming). Increases in the number of interruptions were associated with significant increases in total task completion time ( p = .003). We also found increases in nurses' cognitive workload, nurse frustration, and PCA pump programming errors, but these increases were not statistically significant. Complex technology use permeates the acute care nursing practice environment. These results add new knowledge on nurses' clinical performance during PCA pump programming and high-risk medication administration.
77 FR 31815 - Hazardous Materials Regulations: Combustible Liquids
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-30
... are: Safety (hazard communication and packaging integrity); International commerce (frustration/delay... exempt seasonal workers from the Federal Motor Carrier Safety Administration's Commercial Driver's...: Anyone is able to search the electronic form of any written communications and comments received into any...
ERIC Educational Resources Information Center
Moran, Lyndsey R.; Lengua, Liliana J.; Zalewski, Maureen
2013-01-01
Interactions between reactive and regulatory dimensions of temperament may be particularly relevant to children's adjustment but are examined infrequently. This study investigated these interactions by examining effortful control as a moderator of the relations of fear and frustration reactivity to children's social competence, internalizing, and…
ERIC Educational Resources Information Center
Frangie, Maha
2017-01-01
This paper aims at deepening the understanding of how the relation between home and school is negotiated in the mind of Grade 6 students attending an International Baccalaureate (IB) school in Qatar. Students reported mainly frustration and confusion. The Thematic Coding Analysis used in the study revealed two strategies students use to negotiate…
Christian Realism’s Response to International Terrorism
2002-04-01
defense which cannot be transmuted into instruments of aggression. The frustrations of the average man, who can never realise the power and the...historical existence, tensions have their root in natural, geographic, economic, racial, national and sexual conditions. But since it interprets
Martinez-Torteya, Cecilia; Bogat, G Anne; Lonstein, Joseph S; Granger, Douglas A; Levendosky, Alytia A
2017-10-01
Guided by the main tenets of contemporary models of the developmental origins of health and disease, this study evaluated whether individual differences in reactivity of the hypothalamic-pituitary-adrenal (HPA) axis and Sympathetic Nervous System (SNS) moderate the effect of prenatal exposure to trauma on internalizing and externalizing behaviors during infancy. Participants were a community sample of 182 mothers (M age=25years, 43% Caucasian, 33% Black/African American, 24% Biracial/Other) and their infants (59% girls; M age=11.8months). Each mother completed questionnaires that assessed IPV experienced during pregnancy and also reported on her infant's behavior problems. Infant saliva samples (later assayed for cortisol and sAA) were collected before and after a frustrating task (i.e., arm restraint). Results revealed that the association between in utero IPV and infant internalizing behaviors was most pronounced for infants with asymmetrical HPA-SNS (i.e., high-cortisol and low-sAA) reactivity to frustration, and least pronounced for infants with symmetrical HPA-SNS (i.e., low-cortisol and low-sAA or high-cortisol and high-sAA) reactivity to frustration. Higher levels of externalizing behavior, in contrast, were associated with higher levels of prenatal IPV but unrelated to either cortisol or sAA reactivity to stress. Findings replicate documented associations between maternal IPV exposure during pregnancy and offspring risk. Moreover, findings advance our understanding of individual differences in the developmental origins of health and disease and provide additional evidence that assessing multiple stress biomarkers contributes to a more comprehensive understanding of individual vulnerability to adversity. Copyright © 2017 Elsevier B.V. All rights reserved.
Quantum phase transition with dissipative frustration
NASA Astrophysics Data System (ADS)
Maile, D.; Andergassen, S.; Belzig, W.; Rastelli, G.
2018-04-01
We study the quantum phase transition of the one-dimensional phase model in the presence of dissipative frustration, provided by an interaction of the system with the environment through two noncommuting operators. Such a model can be realized in Josephson junction chains with shunt resistances and resistances between the chain and the ground. Using a self-consistent harmonic approximation, we determine the phase diagram at zero temperature which exhibits a quantum phase transition between an ordered phase, corresponding to the superconducting state, and a disordered phase, corresponding to the insulating state with localized superconducting charge. Interestingly, we find that the critical line separating the two phases has a nonmonotonic behavior as a function of the dissipative coupling strength. This result is a consequence of the frustration between (i) one dissipative coupling that quenches the quantum phase fluctuations favoring the ordered phase and (ii) one that quenches the quantum momentum (charge) fluctuations leading to a vanishing phase coherence. Moreover, within the self-consistent harmonic approximation, we analyze the dissipation induced crossover between a first and second order phase transition, showing that quantum frustration increases the range in which the phase transition is second order. The nonmonotonic behavior is reflected also in the purity of the system that quantifies the degree of correlation between the system and the environment, and in the logarithmic negativity as an entanglement measure that encodes the internal quantum correlations in the chain.
Dieleman, Lisa M; De Pauw, Sarah S W; Soenens, Bart; Mabbe, Elien; Campbell, Rachel; Prinzie, Peter
2018-02-01
Research in parents of youngsters with Autism Spectrum Disorder (ASD) increasingly documents associations between children's problem behaviors and symptom severity and more dysfunctional and less adaptive parenting behaviors. However, the mechanisms underlying these associations have not been examined thoroughly. This study examines the mediating role of parental need frustration in the relation between child maladjustment (i.e., problem behavior and autism severity) and parenting behavior (i.e., controlling and autonomy-supportive parenting). The sample included 95 parents of adolescents/emerging adults with ASD (M age =18.8years, SD=2.3). Parents completed questionnaires assessing their parenting strategies and psychological need frustration as well as the internalizing and externalizing problem behaviors and autism severity of their child. Results indicate that the association between externalizing problems and controlling parenting was partially mediated by need frustration. This suggests that externalizing problems go together with lower feelings of parent-child closeness, lower parental competence, and a decreased sense of volitional functioning, feelings that, in turn, relate to more controlling strategies. Symptom severity has a direct negative association with autonomy support, suggesting that parents lower their autonomy support when their child has high levels of autism symptoms, without experiencing these symptoms as a threat to their own psychological needs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Islands of Empowerment: Facilitating Multicultural Learning Communities in College
ERIC Educational Resources Information Center
Chavez, Alicia Fedelina
2007-01-01
Multiculturally congruent classroom learning environments have remained elusive in United States higher education as colleges strive to recruit, retain, and educate an increasingly diverse population. Frustrations run high amongst domestic and international students of color who find collegiate classrooms in the United States difficult to…
From Global Knowledge to Global Civic Engagement
ERIC Educational Resources Information Center
Lorenzini, Michelle
2013-01-01
In this article, I argue that student learning is enhanced when civic engagement is a component of international education initiatives. When only presented with knowledge about global challenges, students can become frustrated and overwhelmed unless they also understand how they might contribute to solutions. Political science programs are…
Cataloging Expert Systems: Optimism and Frustrated Reality.
ERIC Educational Resources Information Center
Olmstadt, William J.
2000-01-01
Discusses artificial intelligence and attempts to catalog expert systems. Topics include the nature of expertise; examples of cataloging expert systems; barriers to implementation; and problems, including total automation, cataloging expertise, priorities, and system design. (LRW)
NASA Astrophysics Data System (ADS)
Ash, William Mason, III
Total Internal Reflection Holographic Microscopy (TIRHM) combines near-field microscopy with digital holography to produce a new form of near-field phase microscopy. Using a prism in TIR as a near-field imager, the presence of microscopic organisms, cell-substrate interfaces, and adhesions, causes relative refractive index (RRI) and frustrated TIR (f-TIR) to modulate the object beam's evanescent wave phase front. Quantitative phase images of test specimens such as Amoeba proteus, Dictyostelium Discoideum and cells such as SKOV-3 ovarian cancer and 3T3 fibroblasts are produced without the need to introduce stains or fluorophores. The angular spectrum method of digital holography to compensate for tilt anamorphism due to the inclined TIR plane is also discussed. The results of this work conclusively demonstrate, for the first time, the integration of near-field microscopy with digital holography. The cellular images presented show a correlation between the physical extent of the Amoeba proteus plasma membrane and the adhesions that are quantitatively profiled by phase cross-sectioning of the holographic images obtained by digital holography. With its ability to quantitatively characterise cellular adhesion and motility, it is anticipated that TIRHM can be a tool for characterizing and combating cancer metastasis, as well as improving our understanding of morphogenesis and embryogenesis itself.
The Pedagogy of Failure in the Global Market
ERIC Educational Resources Information Center
Silk, Janet
2011-01-01
An American artist and art educator discusses her experience teaching at the American University in Cairo, Egypt (AUC). Students are confronted by local and international discourse about authenticity, integrity and influence. They express their frustration and anxiety about their chances for success in the global art market. The author questions…
Endoparasites must breach host barriers to establish infection and then must survive host internal defenses to cause disease. Such barriers may frustrate attempts to experimentally transmit parasites by ?natural' methods. In addition, the host's condition may affect a study's out...
Computer Conferences and Learning: Authority, Resistance, and Internally Persuasive Discourse.
ERIC Educational Resources Information Center
Cooper, Marilyn M.; Selfe, Cynthia L.
1990-01-01
Describes a nontraditional discourse forum, computer-based conferences, in which students hold written conversations to discuss readings, debate issues, share frustrations, and try to become comfortable with the ideas presented in the classroom. Argues that these computer conferences are powerful learning forums for students because they encourage…
Simplified design of thin-film polarizing beam splitter using embedded symmetric trilayer stack.
Azzam, R M A
2011-07-01
An analytically tractable design procedure is presented for a polarizing beam splitter (PBS) that uses frustrated total internal reflection and optical tunneling by a symmetric LHL trilayer thin-film stack embedded in a high-index prism. Considerable simplification arises when the refractive index of the high-index center layer H matches the refractive index of the prism and its thickness is quarter-wave. This leads to a cube design in which zero reflection for the p polarization is achieved at a 45° angle of incidence independent of the thicknesses of the identical symmetric low-index tunnel layers L and L. Arbitrarily high reflectance for the s polarization is obtained at subwavelength thicknesses of the tunnel layers. This is illustrated by an IR Si-cube PBS that uses an embedded ZnS-Si-ZnS trilayer stack.
Effect of external index of refraction on multimode fiber couplers.
Wang, G Z; Murphy, K A; Claus, R O
1995-12-20
The dependence of the performance of fused-taper multimode fiber couplers on the refractive index of the material surrounding the taper region has been investigated both theoretically and experimentally. It has been identified that for a 2 × 2 multimode fiber coupler there is a range of output-power-coupling ratios for which the effect of the external refractive index is negligible. When the coupler is tapered beyond this region, the performance becomes dependent on the external index of refraction and lossy. To analyze the multimode coupler-loss mechanism, we develop a two-dimensional ray-optics model that incorporates trapped cladding-mode loss and core-mode loss through frustrated total internal reflection.
Computer-simulation results support the experimental observations. Related issues such as coupler fabrication and packaging are also discussed.
Opoku-Boateng, Gloria A.
2015-01-01
User frustration research has been one way of looking into clinicians’ experience with health information technology use and interaction. In order to understand how clinician frustration with Health Information Technology (HIT) use occurs, there is the need to explore Human-Computer Interaction (HCI) literature that addresses both frustration and HIT use. In the past three decades, HCI frustration research has increased and expanded. Researchers have done a lot of work to understand emotions, end-user frustration and affect. This paper uses a historical literature review approach to review the origins of emotion and frustration research and explore the research question; Does HCI research on frustration provide insights on clinicians’ frustration with HIT interfaces? From the literature review HCI research on emotion and frustration provides additional insights that can indeed help explain user frustration in HIT. Different approaches and HCI perspectives also help frame HIT user frustration research as well as inform HIT system design. The paper concludes with a suggested directions on how future design and research may take. PMID:26958238
Opoku-Boateng, Gloria A
2015-01-01
User frustration research has been one way of looking into clinicians' experience with health information technology use and interaction. In order to understand how clinician frustration with Health Information Technology (HIT) use occurs, there is the need to explore Human-Computer Interaction (HCI) literature that addresses both frustration and HIT use. In the past three decades, HCI frustration research has increased and expanded. Researchers have done a lot of work to understand emotions, end-user frustration and affect. This paper uses a historical literature review approach to review the origins of emotion and frustration research and explore the research question; Does HCI research on frustration provide insights on clinicians' frustration with HIT interfaces? From the literature review HCI research on emotion and frustration provides additional insights that can indeed help explain user frustration in HIT. Different approaches and HCI perspectives also help frame HIT user frustration research as well as inform HIT system design. The paper concludes with a suggested directions on how future design and research may take.
Frustration in Condensed Matter and Protein Folding
NASA Astrophysics Data System (ADS)
Li, Z.; Tanner, S.; Conroy, B.; Owens, F.; Tran, M. M.; Boekema, C.
2014-03-01
By means of computer modeling, we are studying frustration in condensed matter and protein folding, including the influence of temperature and Thomson-figure formation. Frustration is due to competing interactions in a disordered state. The key issue is how the particles interact to reach the lowest frustration. The relaxation for frustration is mostly a power function (randomly assigned pattern) or an exponential function (regular patterns like Thomson figures). For the atomic Thomson model, frustration is predicted to decrease with the formation of Thomson figures at zero kelvin. We attempt to apply our frustration modeling to protein folding and dynamics. We investigate the homogeneous protein frustration that would cause the speed of the protein folding to increase. Increase of protein frustration (where frustration and hydrophobicity interplay with protein folding) may lead to a protein mutation. Research is supported by WiSE@SJSU and AFC San Jose.
Frustration in Condensed Matter and Protein Folding
NASA Astrophysics Data System (ADS)
Lorelli, S.; Cabot, A.; Sundarprasad, N.; Boekema, C.
Using computer modeling we study frustration in condensed matter and protein folding. Frustration is due to random and/or competing interactions. One definition of frustration is the sum of squares of the differences between actual and expected distances between characters. If this sum is non-zero, then the system is said to have frustration. A simulation tracks the movement of characters to lower their frustration. Our research is conducted on frustration as a function of temperature using a logarithmic scale. At absolute zero, the relaxation for frustration is a power function for randomly assigned patterns or an exponential function for regular patterns like Thomson figures. These findings have implications for protein folding; we attempt to apply our frustration modeling to protein folding and dynamics. We use coding in Python to simulate different ways a protein can fold. An algorithm is being developed to find the lowest frustration (and thus energy) states possible. Research supported by SJSU & AFC.
Recording Artists in Jamaica: Victims of the System.
ERIC Educational Resources Information Center
Cuthbert, Marlene
Despite the international success of reggae music, a survey of Jamaican recording artists revealed disillusionment, anger and frustration with the national recording industry. Various artists identified a lack of professional ethics and discipline, and above all, lack of an updated copyright law as being at the root of the problem. Since Jamaica…
A Conversation with Paulo Freire.
ERIC Educational Resources Information Center
Benton, Nena
1995-01-01
Paulo Freire's keynote address and subsequent talks with participants at the 1994 International Conference on Experiential Learning in Washington, D.C., reveal his frustration and anger that so many do not have formal education and are dying of hunger. He suggests that we must have hope to emancipate ourselves from those who abuse power. (JOW)
Service beyond Silos: Analyzing Data Trends to Inform the One-Stop Model
ERIC Educational Resources Information Center
Fifolt, Matthew
2010-01-01
Institutions of higher education, like other large organizations, can have complex and complicated administrative structures. Nowhere is this more true than in the area of student services. Internal systems and processes that have become almost second nature to the individuals who staff administrative units can seem confusing and frustrating to…
FAITH, MYLES S.; STOREY, MEGAN; KRAL, TANJA V. E.; PIETROBELLI, ANGELO
2010-01-01
Background There are few validated instruments measuring parental beliefs about parent–child feeding relations and child compliance during meals. Objective To test the validity of the Feeding Demands Questionnaire, a parent-report instrument designed to measure parents’ beliefs about how their child should eat. Methods Participants were 85 mothers of 3- to 7-year-old same-sex twin pairs or sibling pairs, and their children. Mothers completed the eight-item Feeding Demands Questionnaire and the Child Feeding Questionnaire, plus measures of depression and fear of fat. Statistical analyses Psychometric evaluations of the Feeding Demands Questionnaire included principal components analysis, Cronbach’s α for internal consistency, tests for convergent and discriminant validities, and Flesh-Kincaid for readability. Results The Feeding Demands Questionnaire had three underlying factors: anger/frustration, food amount demandingness, and food type demandingness, for which subscales were computed. The Feeding Demands Questionnaire showed acceptable internal consistency (α ranging from .70 to .86) and was written at the 4.8th grade level. Mothers reporting greater anger/frustration during feeding were more likely to pressure their children to eat, while those reporting greater demands about the type of foods their children eat were more likely to monitor child fat intake. Mothers reporting greater demands about the amount of food their children eat were more likely to restrict eating, pressure children to eat, and monitor their fat intake. Conclusions The Feeding Demands Questionnaire appears valid for assessing maternal beliefs that children should comply with rules for eating and frustration during feeding. Different demand beliefs can underlie different feeding practices. PMID:18375218
Van Petegem, Stijn; Soenens, Bart; Vansteenkiste, Maarten; Beyers, Wim
2015-01-01
The present investigation focused on adolescents' defiance against parents by drawing upon psychological reactance theory (Brehm, 1966) and self-determination theory (Ryan & Deci, 2000). Psychological reactance would be elicited when freedom is taken away, thereby motivating individuals to engage in oppositional behavior. Throughout four studies (total N = 1,472, age ranging between 12 and 21 years), it was examined whether a controlling parenting style related to adolescents' experiences of autonomy need frustration (i.e., pressure) and reactance. Reactance, in turn, would relate to more externalizing and internalizing problems. Support was obtained for these associations in community and clinical samples, making use of different informants, and controlling for responsiveness and rule setting. A vignette-based study provided further support. The discussion highlights theoretical and clinical implications. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.
Cryogenic solid Schmidt camera as a base for future wide-field IR systems
NASA Astrophysics Data System (ADS)
Yudin, Alexey N.
2011-11-01
Work is focused on study of capability of solid Schmidt camera to serve as a wide-field infrared lens for aircraft system with whole sphere coverage, working in 8-14 um spectral range, coupled with spherical focal array of megapixel class. Designs of 16 mm f/0.2 lens with 60 and 90 degrees sensor diagonal are presented, their image quality is compared with conventional solid design. Achromatic design with significantly improved performance, containing enclosed soft correcting lens behind protective front lens is proposed. One of the main goals of the work is to estimate benefits from curved detector arrays in 8-14 um spectral range wide-field systems. Coupling of photodetector with solid Schmidt camera by means of frustrated total internal reflection is considered, with corresponding tolerance analysis. The whole lens, except front element, is considered to be cryogenic, with solid Schmidt unit to be flown by hydrogen for improvement of bulk transmission.
How Is Frustration Related to Online Gamer Loyalty? A Synthesis of Multiple Theories.
Huang, Han-Chung; Liao, Gen-Yih; Chiu, Kay-Ling; Teng, Ching-I
2017-11-01
Online games can frustrate their gamers, but little was known about how such frustration impacts gamer loyalty. Because novice and experienced gamers may respond differently to frustration, this study investigates how gamers' frustration influences their loyalty and how this influence may differ between novice and experienced gamers. Because of the complexity of this issue, multiple theories were synthesized to develop the theoretical model. This study collected responses from 558 online gamers. Findings indicate that frustration is positively related to novice gamers' participation in task teams, and subsequently their loyalty. However, frustration is negatively related to the self-efficacy of experienced gamers and to their loyalty.
NASA Astrophysics Data System (ADS)
Mukhin, S. I.; Gnezdilov, N. V.
2018-05-01
We found analytically a first-order quantum phase transition in a Cooper pair box array of N low-capacitance Josephson junctions capacitively coupled to resonant photons in a microwave cavity. The Hamiltonian of the system maps on the extended Dicke Hamiltonian of N spins 1 /2 with infinitely coordinated antiferromagnetic (frustrating) interaction. This interaction arises from the gauge-invariant coupling of the Josephson-junction phases to the vector potential of the resonant photons field. In the N ≫1 semiclassical limit, we found a critical coupling at which the ground state of the system switches to one with a net collective electric dipole moment of the Cooper pair boxes coupled to a super-radiant equilibrium photonic condensate. This phase transition changes from the first to second order if the frustrating interaction is switched off. A self-consistently "rotating" Holstein-Primakoff representation for the Cartesian components of the total superspin is proposed, that enables one to trace both the first- and the second-order quantum phase transitions in the extended and standard Dicke models, respectively.
Meaning and Utility: Keeping the Humanities and Global Education Central to Learning
ERIC Educational Resources Information Center
Carrese, Susan; Kim, Paul; Creeden, Jack
2013-01-01
"Who cares?" and "Why do I need to know this?" are not just tired student mantras to be brushed aside by frustrated teachers. They are the questions about significance that lie at the heart of their work. At a time of both international economic recession and unprecedented global competition, educators and policy-makers too…
Farhan, Alan; Petersen, Charlotte F; Dhuey, Scott; Anghinolfi, Luca; Qin, Qi Hang; Saccone, Michael; Velten, Sven; Wuth, Clemens; Gliga, Sebastian; Mellado, Paula; Alava, Mikko J; Scholl, Andreas; van Dijken, Sebastiaan
2017-10-17
Geometrical frustration occurs when entities in a system, subject to given lattice constraints, are hindered to simultaneously minimize their local interactions. In magnetism, systems incorporating geometrical frustration are fascinating, as their behavior is not only hard to predict, but also leads to the emergence of exotic states of matter. Here, we provide a first look into an artificial frustrated system, the dipolar trident lattice, where the balance of competing interactions between nearest-neighbor magnetic moments can be directly controlled, thus allowing versatile tuning of geometrical frustration and manipulation of ground state configurations. Our findings not only provide the basis for future studies on the low-temperature physics of the dipolar trident lattice, but also demonstrate how this frustration-by-design concept can deliver magnetically frustrated metamaterials.Artificial magnetic nanostructures enable the study of competing frustrated interactions with more control over the system parameters than is possible in magnetic materials. Farhan et al. present a two-dimensional lattice geometry where the frustration can be controlled by tuning the unit cell parameters.
fNIRS Evidence of Prefrontal Regulation of Frustration in Early Childhood
Perlman, Susan B.; Luna, Beatriz; Hein, Tyler C.; Huppert, Theodore J.
2013-01-01
The experience of frustration is common in early childhood, yet some children seem to possess a lower tolerance for frustration than others. Characterizing the biological mechanisms underlying a wide range of frustration tolerance observed in early childhood may inform maladaptive behavior and psychopathology that is associated with this construct. The goal of this study was to measure prefrontal correlates of frustration in 3–5 year-old children, who are not readily adaptable for typical neuroimaging approaches, using functional near infrared spectroscopy (fNIRS). fNIRS of frontal regions were measured as frustration was induced in children through a computer game where a desired and expected prize was “stolen” by an animated dog. A fNIRS general linear model (GLM) was used to quantify the correlation of brain regions with the task and identify areas that were statistically different between the winning and frustrating test conditions. A second-level voxel-based ANOVA analysis was then used to correlate the amplitude of each individual’s brain activation with measure of parent-reported frustration. Experimental results indicated increased activity in the middle prefrontal cortex during winning of a desired prize, while lateral prefrontal cortex activity increased during frustration. Further, activity increase in lateral prefrontal cortex during frustration correlated positively with parent-reported frustration tolerance. These findings point to the role of the lateral prefrontal cortex as a potential region supporting the regulation of emotion during frustration. PMID:23624495
Probing quantum frustrated systems via factorization of the ground state.
Giampaolo, Salvatore M; Adesso, Gerardo; Illuminati, Fabrizio
2010-05-21
The existence of definite orders in frustrated quantum systems is related rigorously to the occurrence of fully factorized ground states below a threshold value of the frustration. Ground-state separability thus provides a natural measure of frustration: strongly frustrated systems are those that cannot accommodate for classical-like solutions. The exact form of the factorized ground states and the critical frustration are determined for various classes of nonexactly solvable spin models with different spatial ranges of the interactions. For weak frustration, the existence of disentangling transitions determines the range of applicability of mean-field descriptions in biological and physical problems such as stochastic gene expression and the stability of long-period modulated structures.
Sun, Yunxiang; Ming, Dengming
2014-01-01
Energetic frustration is becoming an important topic for understanding the mechanisms of protein folding, which is a long-standing big biological problem usually investigated by the free energy landscape theory. Despite the significant advances in probing the effects of folding frustrations on the overall features of protein folding pathways and folding intermediates, detailed characterizations of folding frustrations at an atomic or residue level are still lacking. In addition, how and to what extent folding frustrations interact with protein topology in determining folding mechanisms remains unclear. In this paper, we tried to understand energetic frustrations in the context of protein topology structures or native-contact networks by comparing the energetic frustrations of five homologous Im9 alpha-helix proteins that share very similar topology structures but have a single hydrophilic-to-hydrophobic mutual mutation. The folding simulations were performed using a coarse-grained Gō-like model, while non-native hydrophobic interactions were introduced as energetic frustrations using a Lennard-Jones potential function. Energetic frustrations were then examined at residue level based on φ-value analyses of the transition state ensemble structures and mapped back to native-contact networks. Our calculations show that energetic frustrations have highly heterogeneous influences on the folding of the four helices of the examined structures depending on the local environment of the frustration centers. Also, the closer the introduced frustration is to the center of the native-contact network, the larger the changes in the protein folding. Our findings add a new dimension to the understanding of protein folding the topology determination in that energetic frustrations works closely with native-contact networks to affect the protein folding.
Ferreiro, Diego U; Komives, Elizabeth A; Wolynes, Peter G
2014-11-01
Biomolecules are the prime information processing elements of living matter. Most of these inanimate systems are polymers that compute their own structures and dynamics using as input seemingly random character strings of their sequence, following which they coalesce and perform integrated cellular functions. In large computational systems with finite interaction-codes, the appearance of conflicting goals is inevitable. Simple conflicting forces can lead to quite complex structures and behaviors, leading to the concept of frustration in condensed matter. We present here some basic ideas about frustration in biomolecules and how the frustration concept leads to a better appreciation of many aspects of the architecture of biomolecules, and especially how biomolecular structure connects to function by means of localized frustration. These ideas are simultaneously both seductively simple and perilously subtle to grasp completely. The energy landscape theory of protein folding provides a framework for quantifying frustration in large systems and has been implemented at many levels of description. We first review the notion of frustration from the areas of abstract logic and its uses in simple condensed matter systems. We discuss then how the frustration concept applies specifically to heteropolymers, testing folding landscape theory in computer simulations of protein models and in experimentally accessible systems. Studying the aspects of frustration averaged over many proteins provides ways to infer energy functions useful for reliable structure prediction. We discuss how frustration affects folding mechanisms. We review here how the biological functions of proteins are related to subtle local physical frustration effects and how frustration influences the appearance of metastable states, the nature of binding processes, catalysis and allosteric transitions. In this review, we also emphasize that frustration, far from being always a bad thing, is an essential feature of biomolecules that allows dynamics to be harnessed for function. In this way, we hope to illustrate how Frustration is a fundamental concept in molecular biology.
NASA Technical Reports Server (NTRS)
Washington, Gloria
2012-01-01
Have you heard the saying "frustration is written all over your falce"? Well this saying is true, but that is not the only place. Frustration is written all over your face and your body. The human body has various means to communicate an emotion without the utterance of a single word. The Media Equation says that people interact with computers as if they are human: this includes experiencing frustration. This research measures frustration by monitoring human body-based measures such as heart rate, posture, skin temperature. and respiration. The OCC Theory of Emotions is used to separate frustration into different levels or intensities. The results of this study showed that individual intensities of frustration exist, so that task performance is not degraded. Results from this study can be used by usability testers to model how much frustration is needed before task performance measures start to decrease.
How does Reactivity to Frustrative Non-Reward Increase Risk for Externalizing Symptoms?
Gatzke-Kopp, Lisa M.; Willner, Cynthia J.; Jetha, Michelle K.; Abenavoli, Rachel M.; DuPuis, David; Segalowitz, Sidney J.
2015-01-01
Frustration is a normative affective response with adaptive value in motivating behavior. However, excessive anger in response to frustration characterizes multiple forms of externalizing psychopathology. How a given trait subserves both normative and pathological behavioral profiles is not entirely clear. One hypothesis is that the magnitude of response to frustration differentiates normative versus maladaptive reactivity. Disproportionate increases in arousal in response to frustration may exceed normal regulatory capacity, thus precipitating aggressive or antisocial responses. Alternatively, pathology may arise when reactivity to frustration interferes with other cognitive systems, impairing the individual’s ability to respond to frustration adaptively. In this paper we examine these two hypotheses in a sample of kindergarten children. First we examine whether children with conduct problems (CP; n = 105) are differentiated from comparison children (n = 135) with regard to magnitude of autonomic reactivity (cardiac and electrodermal) across a task that includes a frustrative non-reward block flanked by two reward blocks. Second we examine whether cognitive processing, as reflected by magnitude of the P3b brain response, is disrupted in the context of frustrative non-reward. Results indicate no differences in skin conductance, but a greater increase in heart rate during the frustration block among children in the CP group. Additionally, the CP group was characterized by a pronounced decrement in P3b amplitude during the frustration condition compared with both reward conditions. No interaction between cardiac and P3b measures was observed, suggesting that each system independently reflects a greater sensitivity to frustration in association with externalizing symptom severity. PMID:25937209
How does reactivity to frustrative non-reward increase risk for externalizing symptoms?
Gatzke-Kopp, Lisa M; Willner, Cynthia J; Jetha, Michelle K; Abenavoli, Rachel M; DuPuis, David; Segalowitz, Sidney J
2015-11-01
Frustration is a normative affective response with an adaptive value in motivating behavior. However, excessive anger in response to frustration characterizes multiple forms of externalizing psychopathology. How a given trait subserves both normative and pathological behavioral profiles is not entirely clear. One hypothesis is that the magnitude of response to frustration differentiates normative versus maladaptive reactivity. Disproportionate increases in arousal in response to frustration may exceed normal regulatory capacity, thus precipitating aggressive or antisocial responses. Alternatively, pathology may arise when reactivity to frustration interferes with other cognitive systems, impairing the individual's ability to respond to frustration adaptively. In this paper we examine these two hypotheses in a sample of kindergarten children. First we examine whether children with conduct problems (CP; n=105) are differentiated from comparison children (n=135) with regard to magnitude of autonomic reactivity (cardiac and electrodermal) across a task that includes a frustrative non-reward block flanked by two reward blocks. Second we examine whether cognitive processing, as reflected by magnitude of the P3b brain response, is disrupted in the context of frustrative non-reward. Results indicate no differences in skin conductance, but a greater increase in heart rate during the frustration block among children in the CP group. Additionally, the CP group was characterized by a pronounced decrement in P3b amplitude during the frustration condition compared with both reward conditions. No interaction between cardiac and P3b measures was observed, suggesting that each system independently reflects a greater sensitivity to frustration in association with externalizing symptom severity. Copyright © 2015 Elsevier B.V. All rights reserved.
Puzzling out PISA: What Can International Comparisons Tell Us about American Education?
ERIC Educational Resources Information Center
Schmidt, William H.; Burroughs, Nathan A.
2015-01-01
It is no secret that disadvantaged children are more likely to struggle in school. For decades now, public policy has focused on how to reduce the achievement gap between poorer students and more-affluent students. Despite numerous reform efforts, these gaps remain virtually unchanged--a fact that is deeply frustrating and also a little confusing.…
"The English Is Not the Same": Challenges in Thesis Writing for Second Language Speakers of English
ERIC Educational Resources Information Center
Strauss, Pat
2012-01-01
In this article I describe my interaction as an English for academic purposes (EAP) practitioner with a supervisor and her two postgraduate international students, both of whom were second language speakers of English (L2). Because of linguistic and relationship issues the supervisory experience for the parties was challenging and frustrating. I…
Ferreiro, Diego U.; Komives, Elizabeth A.; Wolynes, Peter G.
2014-01-01
Biomolecules are the prime information processing elements of living matter. Most of these inanimate systems are polymers that compute their own structures and dynamics using as input seemingly random character strings of their sequence, following which they coalesce and perform integrated cellular functions. In large computational systems with a finite interaction-codes, the appearance of conflicting goals is inevitable. Simple conflicting forces can lead to quite complex structures and behaviors, leading to the concept of frustration in condensed matter. We present here some basic ideas about frustration in biomolecules and how the frustration concept leads to a better appreciation of many aspects of the architecture of biomolecules, and how biomolecular structure connects to function. These ideas are simultaneously both seductively simple and perilously subtle to grasp completely. The energy landscape theory of protein folding provides a framework for quantifying frustration in large systems and has been implemented at many levels of description. We first review the notion of frustration from the areas of abstract logic and its uses in simple condensed matter systems. We discuss then how the frustration concept applies specifically to heteropolymers, testing folding landscape theory in computer simulations of protein models and in experimentally accessible systems. Studying the aspects of frustration averaged over many proteins provides ways to infer energy functions useful for reliable structure prediction. We discuss how frustration affects folding mechanisms. We review here how a large part of the biological functions of proteins are related to subtle local physical frustration effects and how frustration influences the appearance of metastable states, the nature of binding processes, catalysis and allosteric transitions. We hope to illustrate how Frustration is a fundamental concept in relating function to structural biology. PMID:25225856
Mabbe, Elien; Soenens, Bart; Vansteenkiste, Maarten; Van Leeuwen, Karla
2016-06-01
This research examined whether and how adolescents' personality traits moderate associations between psychologically controlling parenting and problem behaviors. On the basis of self-determination theory, we also examined the mediating role of psychological need frustration in the effects of psychologically controlling parenting. A cross-sectional study in two samples (N = 423 and 292; Mage = 12.43 and 15.74 years) was conducted. While in Sample 1 both mothers and adolescents provided reports of parenting and problem behavior, Sample 2 relied on adolescent-reported parenting and mother-reported problem behavior. Psychologically controlling parenting was related to internalizing and externalizing problems in both samples. Little systematic evidence was obtained for the moderating role of personality, with the exception of a moderating effect of Agreeableness. In both samples, psychological control was unrelated to externalizing problems among adolescents high on Agreeableness. Analyses of Sample 2 showed that associations between psychological control and problem behavior were mediated by psychological need frustration. Adolescent personality plays a modest role as a moderator of associations between psychologically controlling parenting and problem behavior. Frustration of adolescents' basic and universal psychological needs can account for the undermining effects of psychologically controlling parenting. Directions for future research are discussed. © 2015 Wiley Periodicals, Inc.
Nanoscale control of competing interactions and geometrical frustration in a dipolar trident lattice
Farhan, Alan; Petersen, Charlotte F.; Dhuey, Scott; ...
2017-10-17
Geometrical frustration occurs when entities in a system, subject to given lattice constraints, are hindered to simultaneously minimize their local interactions. In magnetism, systems incorporating geometrical frustration are fascinating, as their behavior is not only hard to predict, but also leads to the emergence of exotic states of matter. Here, we provide a first look into an artificial frustrated system, the dipolar trident lattice, where the balance of competing interactions between nearest-neighbor magnetic moments can be directly controlled, thus allowing versatile tuning of geometrical frustration and manipulation of ground state configurations. Our findings not only provide the basis for futuremore » studies on the low-temperature physics of the dipolar trident lattice, but also demonstrate how this frustration-by-design concept can deliver magnetically frustrated metamaterials.« less
Heat capacity reveals the physics of a frustrated spin tube.
Ivanov, Nedko B; Schnack, Jürgen; Schnalle, Roman; Richter, Johannes; Kögerler, Paul; Newton, Graham N; Cronin, Leroy; Oshima, Yugo; Nojiri, Hiroyuki
2010-07-16
We report on theoretical and experimental results concerning the low-temperature specific heat of the frustrated spin-tube material [(CuCl(2)tachH(3)Cl]Cl(2) (tach denotes 1,3,5-triaminocyclohexane). This substance turns out to be an unusually perfect spin-tube system which allows to study the physics of quasi-one-dimensional antiferromagnetic structures in rather general terms. An analysis of the specific-heat data demonstrates that at low enough temperatures the system exhibits a Tomonaga-Luttinger liquid behavior corresponding to an effective spin-3/2 antiferromagnetic Heisenberg chain with short-range exchange interactions. On the other hand, around 2 K the composite spin structure of the chain is revealed through a Schottky-type peak in the specific heat. We argue that the dominating contribution to the peak originates from gapped magnon-type excitations related to the internal degrees of freedom of the rung spins.
Heat Capacity Reveals the Physics of a Frustrated Spin Tube
NASA Astrophysics Data System (ADS)
Ivanov, Nedko B.; Schnack, Jürgen; Schnalle, Roman; Richter, Johannes; Kögerler, Paul; Newton, Graham N.; Cronin, Leroy; Oshima, Yugo; Nojiri, Hiroyuki
2010-07-01
We report on theoretical and experimental results concerning the low-temperature specific heat of the frustrated spin-tube material [(CuCl2tachH)3Cl]Cl2 (tach denotes 1,3,5-triaminocyclohexane). This substance turns out to be an unusually perfect spin-tube system which allows to study the physics of quasi-one-dimensional antiferromagnetic structures in rather general terms. An analysis of the specific-heat data demonstrates that at low enough temperatures the system exhibits a Tomonaga-Luttinger liquid behavior corresponding to an effective spin-3/2 antiferromagnetic Heisenberg chain with short-range exchange interactions. On the other hand, around 2 K the composite spin structure of the chain is revealed through a Schottky-type peak in the specific heat. We argue that the dominating contribution to the peak originates from gapped magnon-type excitations related to the internal degrees of freedom of the rung spins.
Frustration and quantum criticality
NASA Astrophysics Data System (ADS)
Vojta, Matthias
2018-06-01
This review article is devoted to the interplay between frustrated magnetism and quantum critical phenomena, covering both theoretical concepts and ideas as well as recent experimental developments in correlated-electron materials. The first part deals with local-moment magnetism in Mott insulators and the second part with frustration in metallic systems. In both cases, frustration can either induce exotic phases accompanied by exotic quantum critical points or lead to conventional ordering with unconventional crossover phenomena. In addition, the competition of multiple phases inherent to frustrated systems can lead to multi-criticality.
Odlum, Michelle; Yoon, Sunmoo
2018-03-23
For effective public communication during major disease outbreaks like the 2014-2016 Ebola epidemic, health information needs of the population must be adequately assessed. Through content analysis of social media data, like tweets, public health information needs can be effectively assessed and in turn provide appropriate health information to address such needs. The aim of the current study was to assess health information needs about Ebola, at distinct epidemic time points, through longitudinal tracking. Natural language processing was applied to explore public response to Ebola over time from July 2014 to March 2015. A total 155,647 tweets (unique 68,736, retweet 86,911) mentioning Ebola were analyzed and visualized with infographics. Public fear, frustration, and health information seeking regarding Ebola-related global priorities were observed across time. Our longitudinal content analysis revealed that due to ongoing health information deficiencies, resulting in fear and frustration, social media was at times an impediment and not a vehicle to support health information needs. Content analysis of tweets effectively assessed Ebola information needs. Our study also demonstrates the use of Twitter as a method for capturing real-time data to assess ongoing information needs, fear, and frustration over time.
Fang, Hui; He, Bin; Fu, Huijian; Meng, Liang
2017-01-01
Competence frustration has been consistently found to undermine one's intrinsic motivation in the same activity. However, the relationship between competence frustration in a preceding activity and one's intrinsic motivation in a subsequent one remains unclear. In order to explore this relationship, self-reported data were collected from 617 undergraduate students of a large comprehensive university in southern China, who took varied courses immediately before taking a less-demanding one. Results suggested a U-shaped relationship between students' competence frustration in a preceding course and intrinsic motivation in a subsequent one. To be specific, for students whose competence frustration reached the inflection point, a restoration process would be activated if the current course would help restore their competence. Importantly, these students' competence frustration in a preceding course was found to positively predict their intrinsic motivation level in a subsequent course. As far as we are concerned, this is the first study to reveal a potential positive effect of need frustration outside of its primary thwarting context, which complements and extends existing literatures on the dynamics between need frustration and intrinsic motivation.
Rhoades, Kimberly A; Leve, Leslie D; Harold, Gordon T; Neiderhiser, Jenae M; Shaw, Daniel S; Reiss, David
2011-04-01
We examined direct and indirect pathways from marital hostility to toddler anger/frustration via harsh parenting and parental depressive symptoms, with an additional focus on the moderating role of genetic influences as inferred from birth parent anger/frustration. Participants were 361 linked triads of birth mothers, adoptive parents, and adopted children who were 9 (T1) and 18 (T2) months old across the study period. Results indicated an indirect effect from T1 marital hostility to T2 toddler anger/frustration via T2 parental harsh discipline. Results also indicated that the association between marital hostility and toddler anger was moderated by birth mother anger/frustration. For children whose birth mothers reported high levels of anger/frustration, adoptive parents' marital hostility at T1 predicted toddler anger/frustration at T2. This relation did not hold for children whose birth mothers reported low levels of anger/frustration. The results suggest that children whose birth mothers report elevated frustration might inherit an emotional lability that makes them more sensitive to the effects of marital hostility.
Emergent geometric frustration of artificial magnetic skyrmion crystals
Ma, Fusheng; Reichhardt, Charles; Gan, Weiliang; ...
2016-10-05
Magnetic skyrmions have been receiving growing attention as potential information storage and magnetic logic devices since an increasing number of materials have been identified that support skyrmion phases. Explorations of artificial frustrated systems have led to new insights into controlling and engineering new emergent frustration phenomena in frustrated and disordered systems. Here, we propose a skyrmion spin ice, giving a unifying framework for the study of geometric frustration of skyrmion crystals (SCs) in a nonfrustrated artificial geometrical lattice as a consequence of the structural confinement of skyrmions in magnetic potential wells. The emergent ice rules from the geometrically frustrated SCsmore » highlight a novel phenomenon in this skyrmion system: emergent geometrical frustration. We demonstrate how SC topology transitions between a nonfrustrated periodic configuration and a frustrated icelike ordering can also be realized reversibly. The proposed artificial frustrated skyrmion systems can be annealed into different ice phases with an applied current-induced spin-transfer torque, including a long-range ordered ice rule obeying ground state, as-relaxed random state, biased state, and monopole state. In conclusion, the spin-torque reconfigurability of the artificial skyrmion ice states, difficult to achieve in other artificial spin ice systems, is compatible with standard spintronic device fabrication technology, which makes the semiconductor industrial integration straightforward.« less
Emergent geometric frustration of artificial magnetic skyrmion crystals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, Fusheng; Reichhardt, Charles; Gan, Weiliang
Magnetic skyrmions have been receiving growing attention as potential information storage and magnetic logic devices since an increasing number of materials have been identified that support skyrmion phases. Explorations of artificial frustrated systems have led to new insights into controlling and engineering new emergent frustration phenomena in frustrated and disordered systems. Here, we propose a skyrmion spin ice, giving a unifying framework for the study of geometric frustration of skyrmion crystals (SCs) in a nonfrustrated artificial geometrical lattice as a consequence of the structural confinement of skyrmions in magnetic potential wells. The emergent ice rules from the geometrically frustrated SCsmore » highlight a novel phenomenon in this skyrmion system: emergent geometrical frustration. We demonstrate how SC topology transitions between a nonfrustrated periodic configuration and a frustrated icelike ordering can also be realized reversibly. The proposed artificial frustrated skyrmion systems can be annealed into different ice phases with an applied current-induced spin-transfer torque, including a long-range ordered ice rule obeying ground state, as-relaxed random state, biased state, and monopole state. In conclusion, the spin-torque reconfigurability of the artificial skyrmion ice states, difficult to achieve in other artificial spin ice systems, is compatible with standard spintronic device fabrication technology, which makes the semiconductor industrial integration straightforward.« less
Analyzing the effect of homogeneous frustration in protein folding.
Contessoto, Vinícius G; Lima, Debora T; Oliveira, Ronaldo J; Bruni, Aline T; Chahine, Jorge; Leite, Vitor B P
2013-10-01
The energy landscape theory has been an invaluable theoretical framework in the understanding of biological processes such as protein folding, oligomerization, and functional transitions. According to the theory, the energy landscape of protein folding is funneled toward the native state, a conformational state that is consistent with the principle of minimal frustration. It has been accepted that real proteins are selected through natural evolution, satisfying the minimum frustration criterion. However, there is evidence that a low degree of frustration accelerates folding. We examined the interplay between topological and energetic protein frustration. We employed a Cα structure-based model for simulations with a controlled nonspecific energetic frustration added to the potential energy function. Thermodynamics and kinetics of a group of 19 proteins are completely characterized as a function of increasing level of energetic frustration. We observed two well-separated groups of proteins: one group where a little frustration enhances folding rates to an optimal value and another where any energetic frustration slows down folding. Protein energetic frustration regimes and their mechanisms are explained by the role of non-native contact interactions in different folding scenarios. These findings strongly correlate with the protein free-energy folding barrier and the absolute contact order parameters. These computational results are corroborated by principal component analysis and partial least square techniques. One simple theoretical model is proposed as a useful tool for experimentalists to predict the limits of improvements in real proteins. Copyright © 2013 Wiley Periodicals, Inc.
Yuan, Jiajin; Liu, Yingying; Ding, Nanxiang; Yang, Jiemin
2014-01-01
Studies from European-American cultures consistently reported that expressive suppression was associated with worse emotional consequence (e.g. depression) in comparison with acceptance. However, this conclusion may not apply to Chinese, as suppressing emotional displays to maintain relational harmony is culturally valued in East Asian countries. Thus, the present study examined the effects of suppression and acceptance on the depressive mood induced by a frustrating task in a Chinese sample. Sixty-four subjects were randomly assigned to one of three instructions: suppression, acceptance or no-regulation during a frustrating arithmetic task. The experience of depressive emotion and skin conductance response (SCR) were recorded during pre-frustration baseline, frustration induction and post-frustration recovery phases, respectively. Compared with the control and acceptance instructions, suppression instruction was associated with decreased depressive experiences and smaller SCR activity during frustration. There were no significant differences between acceptance and control groups in both subjective depression and SCR activity during frustration. Moreover, the suppression group showed a better emotional recovery after the frustrating task, in comparison with the acceptance and control groups. Correlation analyses verified that SCR reactivity was a reliable index of experienced depression during the frustration. Expressive suppression is effective in reducing depressive experiences and depression-related physiological activity (SCR) when Chinese people are involved. By contrast, the acceptance of depressive emotion in Chinese people does not produce a similar regulation effect. These findings suggest that cultural context should be considered in understanding the emotional consequences of suppression and acceptance strategies.
The Energy Landscape Analysis of Cancer Mutations in Protein Kinases
Dixit, Anshuman; Verkhivker, Gennady M.
2011-01-01
The growing interest in quantifying the molecular basis of protein kinase activation and allosteric regulation by cancer mutations has fueled computational studies of allosteric signaling in protein kinases. In the present study, we combined computer simulations and the energy landscape analysis of protein kinases to characterize the interplay between oncogenic mutations and locally frustrated sites as important catalysts of allostetric kinase activation. While structurally rigid kinase core constitutes a minimally frustrated hub of the catalytic domain, locally frustrated residue clusters, whose interaction networks are not energetically optimized, are prone to dynamic modulation and could enable allosteric conformational transitions. The results of this study have shown that the energy landscape effect of oncogenic mutations may be allosteric eliciting global changes in the spatial distribution of highly frustrated residues. We have found that mutation-induced allosteric signaling may involve a dynamic coupling between structurally rigid (minimally frustrated) and plastic (locally frustrated) clusters of residues. The presented study has demonstrated that activation cancer mutations may affect the thermodynamic equilibrium between kinase states by allosterically altering the distribution of locally frustrated sites and increasing the local frustration in the inactive form, while eliminating locally frustrated sites and restoring structural rigidity of the active form. The energy landsape analysis of protein kinases and the proposed role of locally frustrated sites in activation mechanisms may have useful implications for bioinformatics-based screening and detection of functional sites critical for allosteric regulation in complex biomolecular systems. PMID:21998754
Ethnic Conflict: The Case of the Kurds
1992-04-01
political context in which the twenty million Kurds now live in Iraq, Turkey, Iran, Syria and Armenia. Focusing on the Iraqi situation, I also suggest...several conditions I feel the Kurds must achieve in order to obtain the necessary international political support needed to achieve a meaningful...is to explore this people; their history, customs, political solidarity, and their frequently frustrated quest for autonomy. Can there be an
[Social and cultural determinants of juvenile deliquency].
Roché, Sébastian
2004-01-01
Our knowledge of juvenile delinquency has progressed considerably since the early 1980s, thanks to self-reported delinquency surveys. They teach us that the determinants of delinquent behaviors among teenagers are dependent on the facility with which the offense is committed, the internal motivation (frustration in the family and school, observational learning of the use of violence in the media) and the weakness of social reactions.
Human Factors of Queuing: A Library Circulation Model.
ERIC Educational Resources Information Center
Mansfield, Jerry W.
1981-01-01
Classical queuing theories and their accompanying service facilities totally disregard the human factors in the name of efficiency. As library managers we need to be more responsive to human needs in the design of service points and make every effort to minimize queuing and queue frustration. Five references are listed. (Author/RAA)
Ding, Nanxiang; Yang, Jiemin
2014-01-01
Background Studies from European-American cultures consistently reported that expressive suppression was associated with worse emotional consequence (e.g. depression) in comparison with acceptance. However, this conclusion may not apply to Chinese, as suppressing emotional displays to maintain relational harmony is culturally valued in East Asian countries. Thus, the present study examined the effects of suppression and acceptance on the depressive mood induced by a frustrating task in a Chinese sample. Method Sixty-four subjects were randomly assigned to one of three instructions: suppression, acceptance or no-regulation during a frustrating arithmetic task. The experience of depressive emotion and skin conductance response (SCR) were recorded during pre-frustration baseline, frustration induction and post-frustration recovery phases, respectively. Results Compared with the control and acceptance instructions, suppression instruction was associated with decreased depressive experiences and smaller SCR activity during frustration. There were no significant differences between acceptance and control groups in both subjective depression and SCR activity during frustration. Moreover, the suppression group showed a better emotional recovery after the frustrating task, in comparison with the acceptance and control groups. Correlation analyses verified that SCR reactivity was a reliable index of experienced depression during the frustration. Conclusions Expressive suppression is effective in reducing depressive experiences and depression-related physiological activity (SCR) when Chinese people are involved. By contrast, the acceptance of depressive emotion in Chinese people does not produce a similar regulation effect. These findings suggest that cultural context should be considered in understanding the emotional consequences of suppression and acceptance strategies. PMID:24827934
Frustration and curvature - Glasses and the cholesteric blue phase
NASA Technical Reports Server (NTRS)
Sethna, J. P.
1983-01-01
An analogy is drawn between continuum elastic theories of the blue phase of cholesteric liquid crystals and recent theories of frustration in configurational glasses. Both involve the introduction of a lattice of disclination lines to relieve frustration; the frustration is due to an intrinsic curvature in the natural form of parallel transport. A continuum theory of configurational glasses is proposed.
Fang, Hui; He, Bin; Fu, Huijian; Meng, Liang
2017-01-01
Competence frustration has been consistently found to undermine one’s intrinsic motivation in the same activity. However, the relationship between competence frustration in a preceding activity and one’s intrinsic motivation in a subsequent one remains unclear. In order to explore this relationship, self-reported data were collected from 617 undergraduate students of a large comprehensive university in southern China, who took varied courses immediately before taking a less-demanding one. Results suggested a U-shaped relationship between students’ competence frustration in a preceding course and intrinsic motivation in a subsequent one. To be specific, for students whose competence frustration reached the inflection point, a restoration process would be activated if the current course would help restore their competence. Importantly, these students’ competence frustration in a preceding course was found to positively predict their intrinsic motivation level in a subsequent course. As far as we are concerned, this is the first study to reveal a potential positive effect of need frustration outside of its primary thwarting context, which complements and extends existing literatures on the dynamics between need frustration and intrinsic motivation. PMID:29312025
Thompson, Katherine A.; Kelly, Nichole R.; Schvey, Natasha A.; Brady, Sheila M.; Courville, Amber B.; Tanofsky-Kraff, Marian; Yanovski, Susan Z.; Yanovski, Jack A.; Shomaker, Lauren B.
2016-01-01
Appearance-related pressures have been associated with binge eating in previous studies. Yet, it is unclear if these pressures are associated with emotional eating or if specific sources of pressure are differentially associated with emotional eating. We studied the associations between multiple sources of appearance-related pressures, including pressure to be thin and pressure to increase muscularity, and emotional eating in 300 adolescents (Mage = 15.3, SD = 1.4, 60% female). Controlling for age, race, puberty, body mass index (BMI) z-score, and sex, both pressure to be thin and pressure to be more muscular from same-sex peers were positively associated with emotional eating in response to feeling angry/frustrated and unsettled (ps<.05). Pressure from same-sex peers to be more muscular also was associated with eating when depressed (p<.05), and muscularity pressure from opposite-sex peers related to eating in response to anger/frustration (p<.05). All associations were fully mediated by internalization of appearance ideals according to Western cultural standards (ps<.001). Associations of pressures from mothers and fathers with emotional eating were non-significant. Results considering sex as a moderator of the associations between appearance-related pressures and emotional eating were non-significant. Findings illustrate that both pressure to be thin and muscular from peers are related to more frequent emotional eating among both boys and girls, and these associations are explained through internalization of appearance-related ideals. PMID:28038437
NASA Astrophysics Data System (ADS)
Hotta, Takashi
2016-02-01
This volume of Journal of Physics: Conference Series contains both invited and contributed papers presented at the International Symposium on "New Quantum Phases Emerging from Novel Crystal Structure", which was held from 24-25 September 2015 at the Minami-Osawa Campus of Tokyo Metropolitan University (TMU). The Graduate School of Science and Engineering of TMU is now promoting a research project on "New Quantum Phases Emerging from Novel Crystal Structure" with the support of the university. This is the cooperative project involving the electrical and electronic engineering and physics departments to discover new quantum phases in strongly correlated electron systems on novel crystal structures, with geometrically characteristic properties such as cage, layered, and geometrical frustrated structures. In this international symposium, we have mainly picked up BiS2-based layered superconductors, cage-structure materials such as 1-2-20 and filled skutterudites, geometrically frustrated systems such as pyrochlore compounds, and noncentrosymmetric materials. Topics on other materials with exotic crystal structure have been also discussed. I believe that this symposium provides a good opportunity to present recent research results on magnetism and superconductivity in such materials, and to discuss future directions of research on strongly correlated electron systems with novel crystal structure. I would like to give thanks, on behalf of the organizing committee, to all participants of the TMU International Symposium and all members of the Advisory Committee, who have contributed to the success of this symposium. I further thank the TMU Research Organization for the financial support of this symposium.
NASA Astrophysics Data System (ADS)
Muttalib, K. A.; Khatun, M.; Barry, J. H.
2017-11-01
Discovery of new materials and improved experimental as well as numerical techniques have led to a renewed interest in geometrically frustrated spin systems. However, there are very few exact results available that can provide a benchmark for comparison. In this work, we calculate exactly the perpendicular susceptibility χ⊥ for an Ising antiferromagnet with (i) nearest-neighbor pair interaction on a kagome lattice where strong frustration prevents long-range ordering and (ii) elementary triplet interactions on a kagome lattice which has no frustration but the system remains disordered down to zero temperature. By comparing with other known exact results with and without frustration, we propose that an appropriately temperature-scaled χ⊥ can be used as a quantitative measure of the degree of frustration in Ising spin systems.
Magnetic phase diagram of a frustrated spin ladder
NASA Astrophysics Data System (ADS)
Sugimoto, Takanori; Mori, Michiyasu; Tohyama, Takami; Maekawa, Sadamichi
2018-04-01
Frustrated spin ladders show magnetization plateaux depending on the rung-exchange interaction and frustration defined by the ratio of first and second neighbor exchange interactions in each chain. This paper reports on its magnetic phase diagram. Using the variational matrix-product state method, we accurately determine phase boundaries. Several kinds of magnetization plateaux are induced by the frustration and the strong correlation among quasiparticles on a lattice. The appropriate description of quasiparticles and their relevant interactions are changed by a magnetic field. We find that the frustration differentiates the triplet quasiparticle from the singlet one in kinetic energy.
Etched beam splitters in InP/InGaAsP.
Norberg, Erik J; Parker, John S; Nicholes, Steven C; Kim, Byungchae; Krishnamachari, Uppiliappan; Coldren, Larry A
2011-01-17
An etched beam splitter (EBS) photonic coupler based on frustrated total internal reflection (FTIR) is designed, fabricated and characterized in the InP/InGaAsP material system. The EBS offers an ultra compact footprint (8x11 μm) and a complete range of bar/cross coupling ratio designs. A novel pre-etching process is developed to achieve sufficient depth of the etched coupling gaps. Fabricated EBS couplers demonstrate insertion loss between 1 and 2.6 dB with transmission (cross-coupling) ≤ 10%. The results show excellent agreement with 3D finite-difference time-domain (FDTD) modeling. The coupling of EBS has weak wavelength dependence in the C-band, making it suitable for wavelength division multiplexing (WDM) or other wide bandwidth applications. Finally, the EBS is integrated with active semiconductor optical amplifier (SOA) and phase-modulator components; using a flattened ring resonator structure, a channelizing filter tunable in both amplitude and center frequency is demonstrated, as well as an EBS coupled ring laser.
Planar and finger-shaped optical tactile sensors for robotic applications
NASA Technical Reports Server (NTRS)
Begej, Stefan
1988-01-01
Progress is described regarding the development of optical tactile sensors specifically designed for application to dexterous robotics. These sensors operate on optical principles involving the frustration of total internal reflection at a waveguide/elastomer interface and produce a grey-scale tactile image that represents the normal (vertical) forces of contact. The first tactile sensor discussed is a compact, 32 x 32 planar sensor array intended for mounting on a parallel-jaw gripper. Optical fibers were employed to convey the tactile image to a CCD camera and microprocessor-based image analysis system. The second sensor had the shape and size of a human fingertip and was designed for a dexterous robotic hand. It contained 256 sensing sites (taxels) distributed in a dual-density pattern that included a tactile fovea near the tip measuring 13 x 13 mm and containing 169 taxels. The design and construction details of these tactile sensors are presented, in addition to photographs of tactile imprints.
In-vitro terahertz spectroscopy of rat skin under the action of dehydrating agents
NASA Astrophysics Data System (ADS)
Kolesnikov, Aleksandr S.; Kolesnikova, Ekaterina A.; Tuchina, Daria K.; Terentyuk, Artem G.; Nazarov, Maxim; Skaptsov, Alexander A.; Shkurinov, Alexander P.; Tuchin, Valery V.
2014-01-01
In the paper we present the results of study of rat skin and rat subcutaneous tumor under the action of dehydrating agents in terahertz (THz) range (15-30 THz). Frustrated Total Internal Reflection (FTIR) spectra were obtained with infrared Fourier spectrometer Nicolet 6700 and then they were recalculated in the transmittance spectra with Omnic software. Experiments were carried out with healthy and xenografted tumor in skin tissue in vitro. As the dehydrating agents 100% glycerol, 40%-water glucose solution, PEG-600, and propylene glycol were used. To determine the effect of the optical clearing agent (OCA), the alterations of terahertz transmittance for the samples were analyzed. The results have shown that PEG-600 and 40%-glucose water solution are the most effective dehydrating agent. The transmittance of healthy skin after PEG-600 application increased approximately by 6% and the transmittance of tumor tissue after PEG- 600 and 40%-glucose water solution application increased approximately by 8%. Obtained data can be useful for further application of terahertz radiation for tumor diagnostics.
Case study of a framing effect in course evaluations.
Lynöe, Niels; Juth, Niklas; Helgesson, Gert
2012-01-01
When new elements are included in the medical curriculum and the total time frame remains unchanged, established disciplines have to shorten their courses. This might bring about frustration among the teachers and students concerned, which in turn might affect how other courses are perceived. Two course evaluations, one before and one after a major change in the curriculum were compared. Comments were also analysed. We found that the students' and teachers' frustration influenced the students' evaluations of a new course in the philosophy of medicine and accordingly brought about an unintended message effect referred to as a framing effect. The results of this observational study indicate that a negative framing effect might influence course-evaluations. We suggest that this study might be used as a point of departure for further empirical studies about negative framing effects.
Phase dynamics of single long Josephson junction in MgB2 superconductor
NASA Astrophysics Data System (ADS)
Chimouriya, Shanker Pd.; Ghimire, Bal Ram; Kim, Ju H.
2018-05-01
A system of perturbed sine Gordon equations is derived to a superconductor-insulator-superconductor (SIS) long Joseph-son junction as an extension of the Ambegaokar-Baratoff relation, following the long route of path integral formalism. A computer simulation is performed by discretizing the equations using finite difference approximation and applied to the MgB2 superconductor with SiO2 as the junction material. The solution of unperturbed sG equation is taken as the initial profile for the simulation and observed how the perturbation terms play the role to modify it. It is found initial profile deformed as time goes on. The variation of total Josephson current has also been observed. It is found that, the perturbation terms play the role for phase frustration. The phase frustration achieves quicker for high tunneling current.
Peterson, Jordan B.
2018-01-01
Although performance feedback is widely employed as a means to improve motivation, the efficacy and reliability of performance feedback is often obscured by individual differences and situational variables. The joint role of these moderating variables remains unknown. Accordingly, we investigate how the motivational impact of feedback is moderated by personality and task-difficulty. Utilizing three samples (total N = 916), we explore how Big Five personality traits moderate the motivational impact of false positive and negative feedback on playful, neutral, and frustrating puzzle tasks, respectively. Conscientious and Neurotic individuals together appear particularly sensitive to task difficulty, becoming significantly more motivated by negative feedback on playful tasks and demotivated by negative feedback on frustrating tasks. Results are discussed in terms of Goal-Setting and Self Determination Theory. Implications for industry and education are considered. PMID:29787593
Ren, Weitong; Li, Wenfei; Wang, Jun; Zhang, Jian; Wang, Wei
2017-10-26
Allosteric proteins are featured by energetic degeneracy of two (or more) functionally relevant conformations, therefore their energy landscapes are often locally frustrated. How such frustration affects the protein folding/binding dynamics is not well understood. Here, by using molecular simulations we study the consequences of local frustration in the dimerization dynamics of allosteric proteins based on a homodimer protein S100A12. Despite of the structural symmetry of the two EF-hand motifs in the three-dimensional structures, the S100A12 homodimer shows allosteric behaviors and local frustration only in half of its structural elements, i.e., the C-terminal EF-hand. We showed that such spatially asymmetric location of frustration leads to asymmetric dimerization pathways, in which the dimerization is dominantly initiated by the interchain binding of the minimally frustrated N-terminal EF-hands, achieving optimal balance between the requirements of rapid conformational switching and interchain assembling to the energy landscapes. We also showed that the local frustration, as represented by the double-basin topography of the energy landscape, gives rise to multiple cross-linked dimerization pathways, in which the dimerization is coupled with the allosteric motions of the C-terminal EF-hands. Binding of metal ions tends to reshape the energy landscape and modulate the dimerization pathways. In addition, by employing the frustratometer method, we showed that the highly frustrated residue-pairs in the C-terminal EF-hand are partially unfolded during the conformational transitions of the native homodimer, leading to lowing of free energy barrier. Our results revealed tight interplay between the local frustration of the energy landscape and the dimerization dynamics for allosteric proteins.
Zhou, Qing; Eisenberg, Nancy; Wang, Yun; Reiser, Mark
2004-05-01
Relations among authoritative and authoritarian parenting styles, children's effortful control and dispositional anger/frustration, and children's social functioning were examined for 425 first and second graders (7-10 years old) in Beijing, China. Parents reported on parenting styles; parents and teachers rated children's effortful control, anger/frustration, externalizing problems, and socially appropriate behaviors: and peers rated aggression and leadership/sociability. High effortful control and low dispositional anger/frustration uniquely predicted Chinese children's high social functioning, and the relation of anger/frustration to social functioning was moderated by effortful control. Authoritarian parenting was associated with children's low effortful control and high dispositional anger/frustration, which (especially effortful control) mediated the negative relation between authoritarian parenting and children's social functioning. Effortful control weakly mediated the positive relation of authoritative parenting to social functioning.
Characterizing and quantifying frustration in quantum many-body systems.
Giampaolo, S M; Gualdi, G; Monras, A; Illuminati, F
2011-12-23
We present a general scheme for the study of frustration in quantum systems. We introduce a universal measure of frustration for arbitrary quantum systems and we relate it to a class of entanglement monotones via an exact inequality. If all the (pure) ground states of a given Hamiltonian saturate the inequality, then the system is said to be inequality saturating. We introduce sufficient conditions for a quantum spin system to be inequality saturating and confirm them with extensive numerical tests. These conditions provide a generalization to the quantum domain of the Toulouse criteria for classical frustration-free systems. The models satisfying these conditions can be reasonably identified as geometrically unfrustrated and subject to frustration of purely quantum origin. Our results therefore establish a unified framework for studying the intertwining of geometric and quantum contributions to frustration.
Role-separating ordering in social dilemmas controlled by topological frustration
NASA Astrophysics Data System (ADS)
Amaral, Marco A.; Perc, Matjaž; Wardil, Lucas; Szolnoki, Attila; da Silva Júnior, Elton J.; da Silva, Jafferson K. L.
2017-03-01
``Three is a crowd" is an old proverb that applies as much to social interactions as it does to frustrated configurations in statistical physics models. Accordingly, social relations within a triangle deserve special attention. With this motivation, we explore the impact of topological frustration on the evolutionary dynamics of the snowdrift game on a triangular lattice. This topology provides an irreconcilable frustration, which prevents anticoordination of competing strategies that would be needed for an optimal outcome of the game. By using different strategy updating protocols, we observe complex spatial patterns in dependence on payoff values that are reminiscent to a honeycomb-like organization, which helps to minimize the negative consequence of the topological frustration. We relate the emergence of these patterns to the microscopic dynamics of the evolutionary process, both by means of mean-field approximations and Monte Carlo simulations. For comparison, we also consider the same evolutionary dynamics on the square lattice, where of course the topological frustration is absent. However, with the deletion of diagonal links of the triangular lattice, we can gradually bridge the gap to the square lattice. Interestingly, in this case the level of cooperation in the system is a direct indicator of the level of topological frustration, thus providing a method to determine frustration levels in an arbitrary interaction network.
Role-separating ordering in social dilemmas controlled by topological frustration.
Amaral, Marco A; Perc, Matjaž; Wardil, Lucas; Szolnoki, Attila; da Silva Júnior, Elton J; da Silva, Jafferson K L
2017-03-01
''Three is a crowd" is an old proverb that applies as much to social interactions as it does to frustrated configurations in statistical physics models. Accordingly, social relations within a triangle deserve special attention. With this motivation, we explore the impact of topological frustration on the evolutionary dynamics of the snowdrift game on a triangular lattice. This topology provides an irreconcilable frustration, which prevents anticoordination of competing strategies that would be needed for an optimal outcome of the game. By using different strategy updating protocols, we observe complex spatial patterns in dependence on payoff values that are reminiscent to a honeycomb-like organization, which helps to minimize the negative consequence of the topological frustration. We relate the emergence of these patterns to the microscopic dynamics of the evolutionary process, both by means of mean-field approximations and Monte Carlo simulations. For comparison, we also consider the same evolutionary dynamics on the square lattice, where of course the topological frustration is absent. However, with the deletion of diagonal links of the triangular lattice, we can gradually bridge the gap to the square lattice. Interestingly, in this case the level of cooperation in the system is a direct indicator of the level of topological frustration, thus providing a method to determine frustration levels in an arbitrary interaction network.
Relative effects of harassment, frustration, and task characteristics on cardiovascular reactivity.
García-León, Ana; Reyes del Paso, Gustavo A; Robles, Humbelina; Vila, Jaime
2003-02-01
Effects of anger induction procedures such as frustration and harassment on cardiovascular reactivity have been demonstrated in a wide range of experimental situations. Similarly, heightened cardiovascular reactivity has been associated with a diverse range of tasks involving active coping, competition and interpersonal interaction. The present study sought to directly compare the relative effects of these two important ways of inducing cardiovascular changes. One hundred and five university students performed two tasks that differed in the degree of active coping and interpersonal competition: a competitive psychomotor task and a problem-solving task. States of anger were induced during both tasks by means of harassment, frustration or frustration+harassment. Task-related changes in heart rate, systolic blood pressure, diastolic blood pressure, pulse volume amplitude and respiratory sinus arrhythmia amplitude were monitored. The competitive psychomotor task produced greater cardiovascular reactivity than did the problem-solving task. Harassment and frustration+harassment provoked more cardiovascular reactivity than did frustration alone. However, harassment and frustration+harassment had the greatest cardiovascular effects in the competitive task, whereas frustration had the greatest cardiovascular effects in the problem-solving task. In this sense, the increases on cardiovascular reactivity seem to depend on the interaction between anger induction procedures and the context in which anger is provoked.
Deliberate exotic magnetism via frustration and topology
NASA Astrophysics Data System (ADS)
Nisoli, Cristiano; Kapaklis, Vassilios; Schiffer, Peter
2017-03-01
Introduced originally to mimic the unusual, frustrated behaviour of spin ice pyrochlores, artificial spin ice can be realized in odd, dedicated geometries that open the door to new manifestations of a higher level of frustration.
Campbell, Rachel; Tobback, Els; Delesie, Liesbeth; Vogelaers, Dirk; Mariman, An; Vansteenkiste, Maarten
2017-12-01
Grounded in self-determination theory, this study tested the hypothesis that the satisfaction and frustration of the psychological needs for autonomy, competence, and relatedness would relate to fatigue and subjective and objective sleep parameters, with stress and negative sleep cognitions playing an explanatory role in these associations. During a stay at a sleep laboratory in Belgium, individuals with unexplained chronic fatigue (N = 160; 78% female) underwent polysomnography and completed a questionnaire at 3 different points in time (i.e., after arrival in the sleep lab, before bedtime, and the following morning) that assessed their need-based experiences and stress during the previous week, fatigue during the preceding day, and sleep-related cognitions and sleep during the previous night. Results indicated that need frustration related to higher stress, which in turn, related to higher evening fatigue. Need frustration also related to poorer subjective sleep quality and shorter sleep duration, as indicated by both subjective and objective shorter total sleep time and subjective (but not objective) longer sleep latency. These associations were accounted for by stress and negative sleep cognitions. These findings suggest that health care professionals working with individuals with unexplained chronic fatigue may consider focusing on basic psychological needs within their therapeutic approach. Copyright © 2017 John Wiley & Sons, Ltd.
Odlum, Michelle; Yoon, Sunmoo
2018-01-01
Introduction: For effective public communication during major disease outbreaks like the 2014-2016 Ebola epidemic, health information needs of the population must be adequately assessed. Through content analysis of social media data, like tweets, public health information needs can be effectively assessed and in turn provide appropriate health information to address such needs. The aim of the current study was to assess health information needs about Ebola, at distinct epidemic time points, through longitudinal tracking. Methods: Natural language processing was applied to explore public response to Ebola over time from July 2014 to March 2015. A total 155,647 tweets (unique 68,736, retweet 86,911) mentioning Ebola were analyzed and visualized with infographics. Results: Public fear, frustration, and health information seeking regarding Ebola-related global priorities were observed across time. Our longitudinal content analysis revealed that due to ongoing health information deficiencies, resulting in fear and frustration, social media was at times an impediment and not a vehicle to support health information needs. Discussion: Content analysis of tweets effectively assessed Ebola information needs. Our study also demonstrates the use of Twitter as a method for capturing real-time data to assess ongoing information needs, fear, and frustration over time. PMID:29707416
Russa, Mary B; Rodriguez, Christina M; Silvia, Paul J
2014-01-01
Although intergenerational patterns of punitive physical punishment garner considerable research attention, the mechanisms by which historical, cognitive, and contextual factors interplay to influence disciplinary responding remains poorly understood. Disciplinary attitudes have been shown to mediate the association between disciplinary history and disciplinary responding. The present study investigated whether frustration influences these mediation effects. Half of a sample of 330 undergraduates was randomly assigned to frustration induction. Structural equation modeling confirmed that, for participants in the frustration condition, the relation between disciplinary history and physical discipline decision-making was fully mediated by attitudes approving physical discipline. In contrast, for respondents in the no-frustration condition, the pathway from disciplinary history to discipline decision-making was only partially mediated by attitudes. Under conditions of frustration, attitudes may become a more central means by which personal disciplinary history is associated with disciplinary decision-making. © 2013 Wiley Periodicals, Inc.
Frustration Sculpts the Early Stages of Protein Folding.
Di Silvio, Eva; Brunori, Maurizio; Gianni, Stefano
2015-09-07
The funneled energy landscape theory implies that protein structures are minimally frustrated. Yet, because of the divergent demands between folding and function, regions of frustrated patterns are present at the active site of proteins. To understand the effects of such local frustration in dictating the energy landscape of proteins, here we compare the folding mechanisms of the two alternative spliced forms of a PDZ domain (PDZ2 and PDZ2as) that share a nearly identical sequence and structure, while displaying different frustration patterns. The analysis, based on the kinetic characterization of a large number of site-directed mutants, reveals that although the late stages for folding are very robust and biased by native topology, the early stages are more malleable and dominated by local frustration. The results are briefly discussed in the context of the energy-landscape theory. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
"I'm a Student…Again"--Unexpected Lessons from a Professor Returning to School
ERIC Educational Resources Information Center
Culver, Tiffany F.
2014-01-01
After receiving notification from administration that faculty could enroll in six semester hours cost-free, Tiffany F. Culver began to consider taking classes. Once she had enrolled in a master's-level counseling course, she soon discovered that she was totally lacking in the student experience as she navigated through frustrating advances in…
Laceulle, Odilia M; Ormel, Johan; Vollebergh, Wilma A M; van Aken, Marcel A G; Nederhof, Esther
2014-03-01
This study aimed to test the vulnerability model of the relationship between temperament and mental disorders using a large sample of adolescents from the TRacking Adolescents Individual Lives' Survey (TRAILS). The vulnerability model argues that particular temperaments can place individuals at risk for the development of mental health problems. Importantly, the model may imply that not only baseline temperament predicts mental health problems prospectively, but additionally, that changes in temperament predict corresponding changes in risk for mental health problems. Data were used from 1195 TRAILS participants. Adolescent temperament was assessed both at age 11 and at age 16. Onset of mental disorders between age 16 and 19 was assessed at age 19, by means of the World Health Organization Composite International Diagnostic Interview (WHO CIDI). Results showed that temperament at age 11 predicted future mental disorders, thereby providing support for the vulnerability model. Moreover, temperament change predicted future mental disorders above and beyond the effect of basal temperament. For example, an increase in frustration increased the risk of mental disorders proportionally. This study confirms, and extends, the vulnerability model. Consequences of both temperament and temperament change were general (e.g., changes in frustration predicted both internalizing and externalizing disorders) as well as dimension specific (e.g., changes in fear predicted internalizing but not externalizing disorders). These findings confirm previous studies, which showed that mental disorders have both unique and shared underlying temperamental risk factors. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.
Thompson, Katherine A; Kelly, Nichole R; Schvey, Natasha A; Brady, Sheila M; Courville, Amber B; Tanofsky-Kraff, Marian; Yanovski, Susan Z; Yanovski, Jack A; Shomaker, Lauren B
2017-01-01
Appearance-related pressures have been associated with binge eating in previous studies. Yet, it is unclear if these pressures are associated with emotional eating or if specific sources of pressure are differentially associated with emotional eating. We studied the associations between multiple sources of appearance-related pressures, including pressure to be thin and pressure to increase muscularity, and emotional eating in 300 adolescents (M age =15.3, SD=1.4, 60% female). Controlling for age, race, puberty, body mass index (BMI) z-score, and sex, both pressure to be thin and pressure to be more muscular from same-sex peers were positively associated with emotional eating in response to feeling angry/frustrated and unsettled (ps<0.05). Pressure from same-sex peers to be more muscular also was associated with eating when depressed (p<0.05), and muscularity pressure from opposite-sex peers related to eating in response to anger/frustration (p<0.05). All associations were fully mediated by internalization of appearance ideals according to Western cultural standards (ps<0.001). Associations of pressures from mothers and fathers with emotional eating were non-significant. Results considering sex as a moderator of the associations between appearance-related pressures and emotional eating were non-significant. Findings illustrate that both pressure to be thin and muscular from peers are related to more frequent emotional eating among both boys and girls, and these associations are explained through internalization of appearance-related ideals. Copyright © 2016 Elsevier Ltd. All rights reserved.
Are Online Learners Frustrated with Collaborative Learning Experiences?
ERIC Educational Resources Information Center
Capdeferro, Neus; Romero, Margarida
2012-01-01
Online education increasingly puts emphasis on collaborative learning methods. Despite the pedagogical advantages of collaborative learning, online learners can perceive collaborative learning activities as frustrating experiences. The purpose of this study was to characterize the feelings of frustration as a negative emotion among online learners…
Quantum electric-dipole liquid on a triangular lattice.
Shen, Shi-Peng; Wu, Jia-Chuan; Song, Jun-Da; Sun, Xue-Feng; Yang, Yi-Feng; Chai, Yi-Sheng; Shang, Da-Shan; Wang, Shou-Guo; Scott, James F; Sun, Young
2016-02-04
Geometric frustration and quantum fluctuations may prohibit the formation of long-range ordering even at the lowest temperature, and therefore liquid-like ground states could be expected. A good example is the quantum spin liquid in frustrated magnets. Geometric frustration and quantum fluctuations can happen beyond magnetic systems. Here we propose that quantum electric-dipole liquids, analogues of quantum spin liquids, could emerge in frustrated dielectrics where antiferroelectrically coupled electric dipoles reside on a triangular lattice. The quantum paraelectric hexaferrite BaFe12O19 with geometric frustration represents a promising candidate for the proposed electric-dipole liquid. We present a series of experimental lines of evidence, including dielectric permittivity, heat capacity and thermal conductivity measured down to 66 mK, to reveal the existence of an unusual liquid-like quantum phase in BaFe12O19, characterized by itinerant low-energy excitations with a small gap. The possible quantum liquids of electric dipoles in frustrated dielectrics open up a fresh playground for fundamental physics.
Parra, R Gonzalo; Schafer, Nicholas P; Radusky, Leandro G; Tsai, Min-Yeh; Guzovsky, A Brenda; Wolynes, Peter G; Ferreiro, Diego U
2016-07-08
The protein frustratometer is an energy landscape theory-inspired algorithm that aims at localizing and quantifying the energetic frustration present in protein molecules. Frustration is a useful concept for analyzing proteins' biological behavior. It compares the energy distributions of the native state with respect to structural decoys. The network of minimally frustrated interactions encompasses the folding core of the molecule. Sites of high local frustration often correlate with functional regions such as binding sites and regions involved in allosteric transitions. We present here an upgraded version of a webserver that measures local frustration. The new implementation that allows the inclusion of electrostatic energy terms, important to the interactions with nucleic acids, is significantly faster than the previous version enabling the analysis of large macromolecular complexes within a user-friendly interface. The webserver is freely available at URL: http://frustratometer.qb.fcen.uba.ar. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.
Rodriguez, Christina M; Russa, Mary Bower; Kircher, John C
2015-08-01
Although frustration has long been implicated in promoting aggression, the potential for poor frustration tolerance to function as a risk factor for physical child abuse risk has received minimal attention. Instead, much of the extant literature has examined the role of anger in physical abuse risk, relying on self-reports of the experience or expression of anger, despite the fact that this methodology is often acknowledged as vulnerable to bias. Therefore, the present investigation examined whether a more implicit, analog assessment of frustration tolerance specifically relevant to parenting would reveal an association with various markers of elevated physical child abuse risk in a series of samples that varied with regard to age, parenting status, and abuse risk. An analog task was designed to evoke parenting-relevant frustration: the task involved completing an unsolvable task while listening to a crying baby or a toddler's temper tantrum; time scores were generated to gauge participants' persistence in the task when encountering such frustration. Across these studies, low frustration tolerance was associated with increased physical child abuse potential, greater use of parent-child aggression in discipline encounters, dysfunctional disciplinary style, support for physical discipline use and physical discipline escalation, and increased heart rate. Future research directions that could better inform intervention and prevention programs are discussed, including working to clarify the processes underlying frustration intolerance and potential interactive influences that may exacerbate physical child abuse. Copyright © 2015 Elsevier Ltd. All rights reserved.
41 CFR 101-26.311 - Frustrated shipments.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Frustrated shipments. 101-26.311 Section 101-26.311 Public Contracts and Property Management Federal Property Management... PROGRAM 26.3-Procurement of GSA Stock Items § 101-26.311 Frustrated shipments. (a) At the request of the...
Affective Pacman: A Frustrating Game for Brain-Computer Interface Experiments
NASA Astrophysics Data System (ADS)
Reuderink, Boris; Nijholt, Anton; Poel, Mannes
We present the design and development of Affective Pacman, a game that induces frustration to study the effect of user state changes on the EEG signal. Affective Pacman is designed to induce frustration for short periods, and allows the synchronous recording of a wide range of sensors, such as physiological sensors and EEG in addition to the game state. A self-assessment is integrated in the game to track changes in user state. Preliminary results indicate a significant effect of the frustration induction on the EEG.
de Castro, A B; Rue, Tessa; Takeuchi, David T
2010-01-01
This study examined the associations between employment frustration and both self-rated physical health (SRPH) and self-rated mental health (SRMH) among Asian American immigrants. A cross-sectional quantitative analysis was conducted utilizing data from 1,181 Asian immigrants participating in the National Latino and Asian American Study. Employment frustration was measured by self-report of having difficulty finding the work one wants because of being of Asian descent. SRPH and SRMH were each assessed using a global one-item measure, with responses ranging from poor to excellent. Control variables included gender, age, ethnicity, education, occupation, income, whether immigrated for employment, years in the United States, English proficiency, and a general measure for everyday discrimination. Ordered logistic regression showed that employment frustration was negatively associated with SRPH. This relationship, however, was no longer significant in multivariate models including English proficiency. The negative association between employment frustration and SRMH persisted even when including all control variables. The findings suggest that Asian immigrants in the United States who experience employment frustration report lower levels of both physical and mental health. However, English proficiency may attenuate the relationship of employment frustration with physical health. © 2010 Wiley Periodicals, Inc.
Study of crystal-field interaction in magnetic frustrated lead pyrochlore Gd2Pb2O7
NASA Astrophysics Data System (ADS)
Swarnakar, D.; Jana, Y. M.
2018-05-01
A fine tuning between the crystal field and the molecular field to adopt unique ground state in frustrated magnetic R2M2O7 pyrochlores structures is made by the variation of chemical pressure at R-site caused by substitution of nonmagnetic cation of M-site. Existence of larger cation at M-site increases the lattice parameter or nearest-neighbor bond distance between magnetic R-spins, and causes subtle changes to the local oxygen environment surrounding each R-ion, thereby reduces the chemical pressure at R-site which leads to a dramatic change in the crystal-field and molecular field. To investigate the effect of chemical pressure, the experimental results of powder magnetic susceptibility and isothermal magnetization of the frustrated compound Gd2Pb2O7 containing largest cation, e.g. lead (Pb), at M4+-sites were simulated and analyzed employing a D3d crystal-field (CF) and anisotropic molecular field at R-sites in the self- consistent mean-field approach. The second-ordered axial parameter B20 and total CF splitting of the ground multiplet Gd-ion in Gd2Pb2O7 are 477 cm-1 and 4.8 cm-1 respectively which are the lowest among their isomorphous counterparts, implying reduced effect of the crystal-field at Gd site in Gd2Pb2O7.
Chang, Yuan-Ping; Wang, Hsiu-Hung; Huang, Shan; Wang, Huang-I
2014-03-01
The current shortage of professional nurses in Taiwan both undermines hospital quality of care and raises hospitals' human resource management costs. Few studies have concurrently investigated the interaction effect between professional commitment and, respectively, the positive and negative work attitudes of nurses. Results of this investigation may help improve strategies designed to raise nurse retention rates. This study used the interaction effects of work excitement and work frustration to assess their influence on the professional commitment of nurses. This study was conducted at one hospital in southern Taiwan and used a cross-sectional design with self-administrated questionnaires. Seven hundred thirty-five nurses completed and submitted valid questionnaires (valid response rate: 68.5%). Exploratory and confirmatory factor analysis confirmed the reliability and validity of the three measurement models of work excitement, work frustration, and professional commitment. Correlation and hierarchical regression analysis verified the direct and interaction effects with the correlations among the three measured variables. Work frustration was higher than work excitement among participants (M = 2.72, SD = 0.71 vs. M = 2.26, SD = 0.62). The mean participant score for professional commitment was 2.72 (SD = 0.45) on a 4-point Likert scale. There was a significant and positive correlation between work excitement and professional commitment and a significant and negative correlation between work frustration and professional commitment. High work frustration had a negative effect on professional commitment, whereas high work excitement had a higher positive effect on professional commitment. The two-way interaction between work excitement and frustration was statistically significant in explaining the effects of professional commitment (p < .01). Nurses often work in conditions that are highly frustrating. Although work excitement has been shown as having a greater influence on professional commitment when nurses experienced the dual work affects simultaneously, work frustration significantly reduces the professional commitment effect of nurses. This study suggests that managers should not only construct a positive and exciting work environment but also work to mitigate the causes of work frustration to promote professional commitment and retention among nurses.
Shea, Joan-Emma; Onuchic, José N.; Brooks, Charles L.
1999-01-01
Topological frustration in an energetically unfrustrated off-lattice model of the helical protein fragment B of protein A from Staphylococcus aureus was investigated. This Gō-type model exhibited thermodynamic and kinetic signatures of a well-designed two-state folder with concurrent collapse and folding transitions and single exponential kinetics at the transition temperature. Topological frustration is determined in the absence of energetic frustration by the distribution of Fersht φ values. Topologically unfrustrated systems present a unimodal distribution sharply peaked at intermediate φ, whereas highly frustrated systems display a bimodal distribution peaked at low and high φ values. The distribution of φ values in protein A was determined both thermodynamically and kinetically. Both methods yielded a unimodal distribution centered at φ = 0.3 with tails extending to low and high φ values, indicating the presence of a small amount of topological frustration. The contacts with high φ values were located in the turn regions between helices I and II and II and III, intimating that these hairpins are in large part required in the transition state. Our results are in good agreement with all-atom simulations of protein A, as well as lattice simulations of a three- letter code 27-mer (which can be compared with a 60-residue helical protein). The relatively broad unimodal distribution of φ values obtained from the all-atom simulations and that from the minimalist model for the same native fold suggest that the structure of the transition state ensemble is determined mostly by the protein topology and not energetic frustration. PMID:10535953
The Point of Creative Frustration and the Creative Process: A New Look at an Old Model.
ERIC Educational Resources Information Center
Sapp, D. David
1992-01-01
This paper offers an extension of Graham Wallas' model of the creative process. It identifies periods of problem solving, incubation, and growth with specific points of initial idea inception, creative frustration, and illumination. Responses to creative frustration are described including denial, rationalization, acceptance of stagnation, and new…
Strong competition between orbital ordering and itinerancy in a frustrated spinel vanadate
Ma, Jie; Lee, Jun Hee; Hahn, Steven E.; ...
2015-01-26
In this study, the crossover from localized to itinerant electron regimes in the geometrically frustrated spinel system Mn 1-xCo xV 2O 4 is explored by neutron-scattering measurements, first-principles calculations, and spin models. At low Co doping, the orbital ordering (OO) of the localized V 3+ spins suppresses magnetic frustration by triggering a tetragonal distortion. At high Co doping levels, however, electronic itinerancy melts the OO and lessens the structural and magnetic anisotropies, thus increasing the amount of geometric frustration for the V-site pyrochlore lattice. Contrary to the predicted paramagentism induced by chemical pressure, the measured noncollinear spin states in themore » Co-rich region of the phase diagram provide a unique platform where localized spins and electronic itinerancy compete in a geometrically frustrated spinel.« less
From Glass Formation to Icosahedral Ordering by Curving Three-Dimensional Space.
Turci, Francesco; Tarjus, Gilles; Royall, C Patrick
2017-05-26
Geometric frustration describes the inability of a local molecular arrangement, such as icosahedra found in metallic glasses and in model atomic glass formers, to tile space. Local icosahedral order, however, is strongly frustrated in Euclidean space, which obscures any causal relationship with the observed dynamical slowdown. Here we relieve frustration in a model glass-forming liquid by curving three-dimensional space onto the surface of a 4-dimensional hypersphere. For sufficient curvature, frustration vanishes and the liquid "freezes" in a fully icosahedral structure via a sharp "transition." Frustration increases upon reducing the curvature, and the transition to the icosahedral state smoothens while glassy dynamics emerge. Decreasing the curvature leads to decoupling between dynamical and structural length scales and the decrease of kinetic fragility. This sheds light on the observed glass-forming behavior in Euclidean space.
NASA Astrophysics Data System (ADS)
Kang, Sung Hoon; Shan, Sicong; Košmrlj, Andrej; Noorduin, Wim L.; Shian, Samuel; Weaver, James C.; Clarke, David R.; Bertoldi, Katia
2014-03-01
Geometrical frustration arises when a local order cannot propagate throughout the space because of geometrical constraints. This phenomenon plays a major role in many systems leading to disordered ground-state configurations. Here, we report a theoretical and experimental study on the behavior of buckling-induced geometrically frustrated triangular cellular structures. To our surprise, we find that buckling induces complex ordered patterns which can be tuned by controlling the porosity of the structures. Our analysis reveals that the connected geometry of the cellular structure plays a crucial role in the generation of ordered states in this frustrated system.
Bandyopadhyay, Boudhayan; Goldenzweig, Adi; Unger, Tamar; Adato, Orit; Fleishman, Sarel J; Unger, Ron; Horovitz, Amnon
2017-12-15
The GroE chaperonin system in Escherichia coli comprises GroEL and GroES and facilitates ATP-dependent protein folding in vivo and in vitro Proteins with very similar sequences and structures can differ in their dependence on GroEL for efficient folding. One potential but unverified source for GroEL dependence is frustration, wherein not all interactions in the native state are optimized energetically, thereby potentiating slow folding and misfolding. Here, we chose enhanced green fluorescent protein as a model system and subjected it to random mutagenesis, followed by screening for variants whose in vivo folding displays increased or decreased GroEL dependence. We confirmed the altered GroEL dependence of these variants with in vitro folding assays. Strikingly, mutations at positions predicted to be highly frustrated were found to correlate with decreased GroEL dependence. Conversely, mutations at positions with low frustration were found to correlate with increased GroEL dependence. Further support for this finding was obtained by showing that folding of an enhanced green fluorescent protein variant designed computationally to have reduced frustration is indeed less GroEL-dependent. Our results indicate that changes in local frustration also affect partitioning in vivo between spontaneous and chaperonin-mediated folding. Hence, the design of minimally frustrated sequences can reduce chaperonin dependence and improve protein expression levels. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
Effect of Frustration on Brain Activation Pattern in Subjects with Different Temperament
Bierzynska, Maria; Bielecki, Maksymilian; Marchewka, Artur; Debowska, Weronika; Duszyk, Anna; Zajkowski, Wojciech; Falkiewicz, Marcel; Nowicka, Anna; Strelau, Jan; Kossut, Malgorzata
2016-01-01
In spite of the prevalence of frustration in everyday life, very few neuroimaging studies were focused on this emotional state. In the current study we aimed to examine effects of frustration on brain activity while performing a well-learned task in participants with low and high tolerance for arousal. Prior to the functional magnetic resonance imaging session, the subjects underwent 2 weeks of Braille reading training. Frustration induction was obtained by using a novel highly difficult tactile task based on discrimination of Braille-like raised dots patterns and negative feedback. Effectiveness of this procedure has been confirmed in a pilot study using galvanic skin response and questionnaires. Brain activation pattern during tactile discrimination task before and after frustration were compared directly. Results revealed changes in brain activity in structures mostly reported in acute stress studies: striatum, cingulate cortex, insula, middle frontal gyrus and precuneus and in structures engaged in tactile Braille discrimination: SI and SII. Temperament type affected activation pattern. Subjects with low tolerance for arousal showed higher activation in the posterior cingulate gyrus, precuneus, and inferior parietal lobule than high reactivity group. Even though performance in the discrimination trials following frustration was unaltered, we observed increased activity of primary and secondary somatosensory cortex processing the tactile information. We interpret this effect as an indicator of additional involvement required to counteract the effects of frustration. PMID:26793136
Effect of Frustration on Brain Activation Pattern in Subjects with Different Temperament.
Bierzynska, Maria; Bielecki, Maksymilian; Marchewka, Artur; Debowska, Weronika; Duszyk, Anna; Zajkowski, Wojciech; Falkiewicz, Marcel; Nowicka, Anna; Strelau, Jan; Kossut, Malgorzata
2015-01-01
In spite of the prevalence of frustration in everyday life, very few neuroimaging studies were focused on this emotional state. In the current study we aimed to examine effects of frustration on brain activity while performing a well-learned task in participants with low and high tolerance for arousal. Prior to the functional magnetic resonance imaging session, the subjects underwent 2 weeks of Braille reading training. Frustration induction was obtained by using a novel highly difficult tactile task based on discrimination of Braille-like raised dots patterns and negative feedback. Effectiveness of this procedure has been confirmed in a pilot study using galvanic skin response and questionnaires. Brain activation pattern during tactile discrimination task before and after frustration were compared directly. Results revealed changes in brain activity in structures mostly reported in acute stress studies: striatum, cingulate cortex, insula, middle frontal gyrus and precuneus and in structures engaged in tactile Braille discrimination: SI and SII. Temperament type affected activation pattern. Subjects with low tolerance for arousal showed higher activation in the posterior cingulate gyrus, precuneus, and inferior parietal lobule than high reactivity group. Even though performance in the discrimination trials following frustration was unaltered, we observed increased activity of primary and secondary somatosensory cortex processing the tactile information. We interpret this effect as an indicator of additional involvement required to counteract the effects of frustration.
2011-05-05
disease danger was exacerbated by the introduction of cholera into post-earthquake Haiti, likely by Nepalese United Nation aiel workers, which caused... Mexico ," MSNBC; 5 September 2007.· U.S. Agency for International Development Office of Foreign Disaster Assistance, Fact Sheet #25, Fiscal Year...March 2011. 29 47 Matt Gutman, "Haiti: As Cholera Spreads, Frustration Builds," ABC News; 18 November 2010. 48 LTC James Ware (US Army, Retired
FIM, a Novel FTIR-Based Imaging Method for High Throughput Locomotion Analysis
Otto, Nils; Löpmeier, Tim; Valkov, Dimitar; Jiang, Xiaoyi; Klämbt, Christian
2013-01-01
We designed a novel imaging technique based on frustrated total internal reflection (FTIR) to obtain high resolution and high contrast movies. This FTIR-based Imaging Method (FIM) is suitable for a wide range of biological applications and a wide range of organisms. It operates at all wavelengths permitting the in vivo detection of fluorescent proteins. To demonstrate the benefits of FIM, we analyzed large groups of crawling Drosophila larvae. The number of analyzable locomotion tracks was increased by implementing a new software module capable of preserving larval identity during most collision events. This module is integrated in our new tracking program named FIMTrack which subsequently extracts a number of features required for the analysis of complex locomotion phenotypes. FIM enables high throughput screening for even subtle behavioral phenotypes. We tested this newly developed setup by analyzing locomotion deficits caused by the glial knockdown of several genes. Suppression of kinesin heavy chain (khc) or rab30 function led to contraction pattern or head sweeping defects, which escaped in previous analysis. Thus, FIM permits forward genetic screens aimed to unravel the neural basis of behavior. PMID:23349775
[Validation of the German Version of Tinnitus Functional Index (TFI)].
Brüggemann, Petra; Szczepek, Agnieszka J; Kleinjung, Tobias; Ojo, Michael; Mazurek, Birgit
2017-09-01
Tinnitus belongs to seriously debilitating auditory conditions and is often complicated by comorbidities such as insomnia, difficulties with concentration, depression, frustration and irritability. To facilitate the grading of symptoms and the effects of therapeutic strategies, we validated a German-version Tinnitus Functional Index (TFI) in 229 subjects suffering from chronic tinnitus. Outcome validity was assessed using the Tinnitus Questionnaire (TQ, German adaptation by Goebel u. Hiller [1998]). Construct validity was assessed using the "Hamburger Allgemeine Depressionsskala" (HADS). The German TFI featured excellent internal consistency (total score Cronbach's α=0.93). Factor analysis disclosed eight TFI subscales as proposed earlier by Meikle et al. [2012]. Intercorrelations were strong both between the TFI and the TQ (r=0.83), and between the TFI and the HADS (depression r=0.49, anxiety r=0.51). The German-version TFI qualifies as a rapid and statistically robust tool for grading the impact of tinnitus on daily living and for the measurements of therapeutic effects. Regarding depressive symptomatology, sensitivity of the TFI was comparable to that of the TQ. © Georg Thieme Verlag KG Stuttgart · New York.
Scattering by multiple cylinders located on both sides of an interface
NASA Astrophysics Data System (ADS)
Lee, Siu-Chun
2018-07-01
The solution for scattering by multiple parallel infinite cylinders located in adjacent half spaces with dissimilar refractive index is presented in this paper. The incident radiation is an arbitrarily polarized plane wave propagating in the upper half space in the plane perpendicular to the axis of the cylinders. The formulation of the electromagnetic field vectors utilized Hertz potentials that are expressed in terms of an expansion of cylindrical wave functions. It accounts for the near-field multiple scattering, Fresnel effect at the interface, and interaction between cylinders in both half spaces. Analytical formulas are derived for the electromagnetic field and Poynting vector in the far-field. The present solution provides the theoretical framework for deducing the solutions for scattering by cylinders located on either side of an interface irradiated by a propagating or an evanescent incident wave. Deduction of these solutions from the present formulation is demonstrated. Numerical results are presented to illustrate the frustration of total internal reflection and scattering of light beyond the critical angle by nanocylinders located in either or both half spaces.
NASA Astrophysics Data System (ADS)
Kukushkin, V. A.
2017-10-01
A way to significantly increase the spatial resolution of the color center photoluminescence collection in chemically vapor-deposited (CVD) diamond at a fixed exciting beam focal volume is suggested. It is based on the creation of a narrow waveguide for the color center photoluminescence with a small number of allowed vertical indices of guided modes. The waveguide is formed between the top surface of a CVD diamond film and an underlaid mirror—a Bragg superlattice made of interchanging high- and low boron-doped layers of CVD diamond. The guided color center photoluminescence is extracted through the top surface of a CVD diamond film with the frustrated total internal reflection method. According to the results of simulation made for a case when color centers are nitrogen-vacancy (NV) centers, the suggested way allows to increase the maximal value of the NV center concentration still compatible with selective collection of their photoluminescence by several times at a fixed exciting beam focal volume. This increase is provided without the deterioration of the NV center photoluminescence collection efficiency.
Partial squeeze film levitation modulates fingertip friction.
Wiertlewski, Michaël; Fenton Friesen, Rebecca; Colgate, J Edward
2016-08-16
When touched, a glass plate excited with ultrasonic transverse waves feels notably more slippery than it does at rest. To study this phenomenon, we use frustrated total internal reflection to image the asperities of the skin that are in intimate contact with a glass plate. We observed that the load at the interface is shared between the elastic compression of the asperities of the skin and a squeeze film of air. Stroboscopic investigation reveals that the time evolution of the interfacial gap is partially out of phase with the plate vibration. Taken together, these results suggest that the skin bounces against the vibrating plate but that the bounces are cushioned by a squeeze film of air that does not have time to escape the interfacial separation. This behavior results in dynamic levitation, in which the average number of asperities in intimate contact is reduced, thereby reducing friction. This improved understanding of the physics of friction reduction provides key guidelines for designing interfaces that can dynamically modulate friction with soft materials and biological tissues, such as human fingertips.
Partial squeeze film levitation modulates fingertip friction
Wiertlewski, Michaël; Fenton Friesen, Rebecca; Colgate, J. Edward
2016-01-01
When touched, a glass plate excited with ultrasonic transverse waves feels notably more slippery than it does at rest. To study this phenomenon, we use frustrated total internal reflection to image the asperities of the skin that are in intimate contact with a glass plate. We observed that the load at the interface is shared between the elastic compression of the asperities of the skin and a squeeze film of air. Stroboscopic investigation reveals that the time evolution of the interfacial gap is partially out of phase with the plate vibration. Taken together, these results suggest that the skin bounces against the vibrating plate but that the bounces are cushioned by a squeeze film of air that does not have time to escape the interfacial separation. This behavior results in dynamic levitation, in which the average number of asperities in intimate contact is reduced, thereby reducing friction. This improved understanding of the physics of friction reduction provides key guidelines for designing interfaces that can dynamically modulate friction with soft materials and biological tissues, such as human fingertips. PMID:27482117
Resonant optical tunneling-induced enhancement of the photonic spin Hall effect
NASA Astrophysics Data System (ADS)
Jiang, Xing; Wang, Qingkai; Guo, Jun; Zhang, Jin; Chen, Shuqing; Dai, Xiaoyu; Xiang, Yuanjiang
2018-04-01
Due to the quantum analogy with optics, the resonant optical tunneling effect (ROTE) has been proposed to investigate both the fundamental physics and the practical applications of optical switches and liquid refractive index sensors. In this paper, the ROTE is used to enhance the spin Hall effect (SHE) of transmitted light. It is demonstrated that sandwiching a layer of a high-refractive-index medium (boron nitride crystal) between two low-refractive-index layers (silica) can effectively enhance the photonic SHE due to the increased refractive index gradient and an enhanced evanescent field near the interface between silica and boron nitride. A maximum transverse shift of the horizontal polarization state in the ROTE structure of about 22.25 µm has been obtained, which is at least three orders of magnitude greater than the transverse shift in the frustrated total internal reflection structure. Moreover, the SHE can be manipulated by controlling the component materials and the thickness of the ROTE structure. These findings open the possibility for future applications of photonic SHE in precision metrology and spin-based photonics.
Compact pulsed high-energy Er:glass laser
NASA Astrophysics Data System (ADS)
Wan, Peng; Liu, Jian
2012-03-01
Bulk Erbium-doped lasers are widely used for long-distance telemetry and ranging. In some applications such as coherent Doppler radars, laser outputs with a relatively long pulse width, good beam profile and pulse shape are required. High energy Q-switched Er:glass lasers were demonstrated by use of electro-optic (E/O) Q-switching or frustrated total internal reflection (FTIR) Q-switching. However, the output pulse durations in these lasers were fixed to relatively small values and extremely hard to tune. We report here on developing a novel and compact Q-switched Er:Yb co-doped phosphate glass laser at an eye-safe wavelength of 1.5 μm. A rotating mirror was used as a Q-switch. Co-linear pump scheme was used to maintain a good output beam profile. Near-perfect Gaussian temporal shape was obtained in our experiment. By changing motor rotation speed, pulse duration was tunable and up to 240 ns was achieved. In our preliminary experiment, output pulse energies of 44 mJ and 4.5 mJ were obtained in free-running and Q-switched operation modes respectively.
ERIC Educational Resources Information Center
de Guzman, Allan B.; Santos, Charisse Izobelle Q.; Santos, Ivan Benedict A.; Santos, Jedda A.; Santos, Justin E.; Santos, Justo Martin S.; Santos, Vincent Emmanuelle E.
2012-01-01
While it is true that elderly concepts of care and caring expectations have been ascertained in previous literatures, little is known about how the elderly population views caring frustrations--particularly that of the Filipino elderly. This study purports to surface the lebenswelt of healthcare expectations and frustrations based on the…
ERIC Educational Resources Information Center
Eckwall, Eldon E.; English, Judy K.
Using a polygraph to determine the reading frustration level of 62 third-, fourth-, and fifth-grade students, the researchers examined several factors related to reading frustration on informal reading inventories. Two primary concerns of the study were (1) to determine whether factors of intelligence, age, sex, ethnic background, reading level,…
Developmental Changes in the Rosenzweig Picture--Frustration Study, Children's Form.
ERIC Educational Resources Information Center
Graybill, Daniel
1987-01-01
Study examined the validity of 1948 norms of the Picture-Frustration Study, Children's Form. Instrument was administered to 140 children, grades 2 through 6, as part of a project investigating effects of video games. Though findings differed from the 1948 norms, they supported the validity of the Children's Form of the Picture-Frustration Study.…
Li, Tingting; Wang, Wei; Zhao, Haijian; He, Falin; Zhong, Kun; Yuan, Shuai; Wang, Zhiguo
2017-09-07
This study aimed to investigate the status of internal quality control (IQC) for cardiac biomarkers from 2011 to 2016 so that we can have overall knowledge of the precision level of measurements in China and set appropriate precision specifications. Internal quality control data of cardiac biomarkers, including creatinine kinase MB (CK-MB) (μg/L), CK-MB(U/L), myoglobin (Mb), cardiac troponin I (cTnI), cardiac troponin T (cTnT), and homocysteines (HCY), were collected by a web-based external quality assessment (EQA) system. Percentages of laboratories meeting five precision quality specifications for current coefficient of variations (CVs) were calculated. Then, appropriate precision specifications were chosen for these six analytes. Finally, the CVs and IQC practice were further analyzed with different grouping methods. The current CVs remained nearly constant for 6 years. cTnT had the highest pass rates every year against five specifications, whereas HCY had the lowest pass rates. Overall, most analytes had a satisfactory performance (pass rates >80%), except for HCY, if one-third TEa or the minimum specification were employed. When the optimal specification was applied, the performance of most analytes was frustrating (pass rates < 60%) except for cTnT. The appropriate precision specifications of Mb, cTnI, cTnT and HCY were set as current CVs less than 9.20%, 9.90%, 7.50%, 10.54%, 7.63%, and 6.67%, respectively. The data of IQC practices indicated wide variation and substantial progress. The precision performance of cTnT was already satisfying, while the other five analytes, especially HCY, were still frustrating; thus, ongoing investigation and continuous improvement for IQC are still needed. © 2017 Wiley Periodicals, Inc.
Noncollinear magnetic ordering in a frustrated magnet: Metallic regime and the role of frustration
NASA Astrophysics Data System (ADS)
Shahzad, Munir; Sengupta, Pinaki
2017-12-01
We explore the magnetic phases in a Kondo lattice model on the geometrically frustrated Shastry-Sutherland lattice at metallic electron densities, searching for noncollinear and noncoplanar spin textures. Motivated by experimental observations in many rare-earth-based frustrated metallic magnets, we treat the local moments as classical spins and set the coupling between the itinerant electrons and local moments as the largest energy scale in the problem. Our results show that a noncollinear flux state is stabilized over an extended range of Hamiltonian parameters. These spin states can be quenched efficiently by external fields like temperature and magnetic field as well as by varying the degree of frustration in the electronic itinerancy and exchange coupling between local moments. Interestingly, unlike insulating electron densities that we discussed in paper I of this sequence, a Dzyaloshinskii-Moriya interaction between the local moments is not essential for the emergence of their noncollinear ordering.
Maxson, Michelle E; Naj, Xenia; O'Meara, Teresa R; Plumb, Jonathan D; Cowen, Leah E
2018-01-01
Candida albicans hyphae can reach enormous lengths, precluding their internalization by phagocytes. Nevertheless, macrophages engulf a portion of the hypha, generating incompletely sealed tubular phagosomes. These frustrated phagosomes are stabilized by a thick cuff of F-actin that polymerizes in response to non-canonical activation of integrins by fungal glycan. Despite their continuity, the surface and invaginating phagosomal membranes retain a strikingly distinct lipid composition. PtdIns(4,5)P2 is present at the plasmalemma but is not detectable in the phagosomal membrane, while PtdIns(3)P and PtdIns(3,4,5)P3 co-exist in the phagosomes yet are absent from the surface membrane. Moreover, endo-lysosomal proteins are present only in the phagosomal membrane. Fluorescence recovery after photobleaching revealed the presence of a diffusion barrier that maintains the identity of the open tubular phagosome separate from the plasmalemma. Formation of this barrier depends on Syk, Pyk2/Fak and formin-dependent actin assembly. Antimicrobial mechanisms can thereby be deployed, limiting the growth of the hyphae. PMID:29553370
Wrinkles of graphene on Ir(111): Macroscopic network ordering and internal multi-lobed structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petrovic, Marin; Sadowski, Jerzy T.; Siber, Antonio
The large-scale production of graphene monolayer greatly relies on epitaxial samples which often display stress-relaxation features in the form of wrinkles. Wrinkles of graphene on Ir(111) are found to exhibit a fairly well ordered interconnecting network which is characterized by low-energy electron microscopy (LEEM). The high degree of quasi-hexagonal network arrangement for the graphene aligned to the underlying substrate can be well described as a (non-Poissonian) Voronoi partition of a plane. The results obtained strongly suggest that the wrinkle network is frustrated at low temperatures, retaining the order inherited from elevated temperatures when the wrinkles interconnect in junctions which mostmore » often join three wrinkles. Such frustration favors the formation of multi-lobed wrinkles which are found in scanning tunneling microscopy (STM) measurements. The existence of multiple lobes is explained within a model accounting for the interplay of the van der Waals attraction between graphene and iridium and bending energy of the wrinkle. The presented study provides new insights into wrinkling of epitaxial graphene and can be exploited to further expedite its application.« less
Cross-cultural sex differences in situational triggers of aggressive responses.
Zajenkowska, Anna; Mylonas, Kostas; Lawrence, Claire; Konopka, Karolina; Rajchert, Joanna
2014-10-01
This paper examines male and female individual differences in situational triggers of aggressive responses (STAR) in three countries as well as cross-cultural sex differences in trait aggression (aggression questionnaire, AQ). Convenience sampling was employed (university students) for the descriptive correlational study (Poland N = 300, 63% female, mean age 21.86, SD = 2.12; UK N = 196, 60% female, mean age 20.48, SD = 3.79; Greece N = 299, 57% female, mean age 20.71, SD = 4.42). The results showed that the STAR scale is an equivalent construct across all three countries. Overall, females were more sensitive to both provocation (SP) and frustration (SF) than males. When controlling for trait aggression, Polish and Greek females scored similarly in SP and higher than UK females. No sex differences in SP or SF were found in the UK sample. Additionally, Polish participants scored the highest in SP. Furthermore, when trait aggression was removed, the Greek participants were most sensitive to frustration, whereas Polish and English participants' SF did not differ. We discuss the results with regard to intercultural differences between investigated countries. © 2014 International Union of Psychological Science.
Wiersma, Valerie R; de Bruyn, Marco; Wei, Yunwei; van Ginkel, Robert J; Hirashima, Mitsuomi; Niki, Toshiro; Nishi, Nozomu; Zhou, Jin; Pouwels, Simon D; Samplonius, Douwe F; Nijman, Hans W; Eggleton, Paul; Helfrich, Wijnand; Bremer, Edwin
2015-01-01
Oncogenic mutation of KRAS (Kirsten rat sarcoma viral oncogene homolog) in colorectal cancer (CRC) confers resistance to both chemotherapy and EGFR (epidermal growth factor receptor)-targeted therapy. We uncovered that KRAS mutant (KRASmut) CRC is uniquely sensitive to treatment with recombinant LGALS9/Galectin-9 (rLGALS9), a recently established regulator of epithelial polarity. Upon treatment of CRC cells, rLGALS9 rapidly internalizes via early- and late-endosomes and accumulates in the lysosomal compartment. Treatment with rLGALS9 is accompanied by induction of frustrated autophagy in KRASmut CRC, but not in CRC with BRAF (B-Raf proto-oncogene, serine/threonine kinase) mutations (BRAFmut). In KRASmut CRC, rLGALS9 acts as a lysosomal inhibitor that inhibits autophagosome-lysosome fusion, leading to autophagosome accumulation, excessive lysosomal swelling and cell death. This antitumor activity of rLGALS9 directly correlates with elevated basal autophagic flux in KRASmut cancer cells. Thus, rLGALS9 has potent antitumor activity toward refractory KRASmut CRC cells that may be exploitable for therapeutic use. PMID:26086204
Wrinkles of graphene on Ir(111): Macroscopic network ordering and internal multi-lobed structure
Petrovic, Marin; Sadowski, Jerzy T.; Siber, Antonio; ...
2015-07-17
The large-scale production of graphene monolayer greatly relies on epitaxial samples which often display stress-relaxation features in the form of wrinkles. Wrinkles of graphene on Ir(111) are found to exhibit a fairly well ordered interconnecting network which is characterized by low-energy electron microscopy (LEEM). The high degree of quasi-hexagonal network arrangement for the graphene aligned to the underlying substrate can be well described as a (non-Poissonian) Voronoi partition of a plane. The results obtained strongly suggest that the wrinkle network is frustrated at low temperatures, retaining the order inherited from elevated temperatures when the wrinkles interconnect in junctions which mostmore » often join three wrinkles. Such frustration favors the formation of multi-lobed wrinkles which are found in scanning tunneling microscopy (STM) measurements. The existence of multiple lobes is explained within a model accounting for the interplay of the van der Waals attraction between graphene and iridium and bending energy of the wrinkle. The presented study provides new insights into wrinkling of epitaxial graphene and can be exploited to further expedite its application.« less
Winter, David G
2010-12-01
Several decades of research have established that implicit achievement motivation (n Achievement) is associated with success in business, particularly in entrepreneurial or sales roles. However, several political psychology studies have shown that achievement motivation is not associated with success in politics; rather, implicit power motivation often predicts political success. Having versus lacking control may be a key difference between business and politics. Case studies suggest that achievement-motivated U.S. presidents and other world leaders often become frustrated and thereby fail because of lack of control, whereas power-motivated presidents develop ways to work with this inherent feature of politics. A reevaluation of previous research suggests that, in fact, relationships between achievement motivation and business success only occur when control is high. The theme of control is also prominent in the development of achievement motivation. Cross-national data are also consistent with this analysis: In democratic industrialized countries, national levels of achievement motivation are associated with strong executive control. In countries with low opportunity for education (thus fewer opportunities to develop a sense of personal control), achievement motivation is associated with internal violence. Many of these manifestations of frustrated achievement motivation in politics resemble authoritarianism. This conclusion is tested by data from a longitudinal study of 113 male college students, showing that high initial achievement motivation combined with frustrated desires for control is related to increases in authoritarianism (F-scale scores) during the college years. Implications for the psychology of leadership and practical politics are discussed. © 2010 The Author. Journal of Personality © 2010, Wiley Periodicals, Inc.
Phosphorylation-induced changes in the energetic frustration in human Tank binding kinase 1.
Husain, Shahrukh; Kumar, Vijay; Hassan, Md Imtaiyaz
2018-07-14
Tank binding kinase 1 (TBK-1) plays an important role in immunity, inflammation, autophagy, cell growth and proliferation. Nevertheless, a key molecular and structural detail of TBK-1 phosphorylation and activation has been largely unknown. Here we investigated the energy landscape of phosphorylated (active) and unphosphorylated (inactive) forms of human TBK-1 to characterize the interplay between phosphorylation and local frustration. By employing the algorithm equipped with energy function and implemented in Frustratometer web-server (http://www.frustratometer.tk), we quantify the role of frustration in the activation of TBK-1. Accordingly, the conformational changes were observed in phosphoregulated active and inactive TBK-1. Substantial changes in frustration, flexibility and interatomic motions were observed among different forms of TBK-1. Structurally rigid kinase domain constitutes a minimally frustrated hub in the core of the catalytic domain, and highly frustrated clusters mainly at the C-lobe might enable the conformational transitions during activation. Also, a large network of highly frustrated interactions is found in the SDD domain of TBK-1 involved in protein-protein interactions and dimerization. The contact maps of the activation loop and α-C helix of kinase domain showed significant changes upon phosphorylation. Cross correlation analysis indicate that both intra and inter subunit correlated motions increases with phosphorylation of TBK-1. Phosphorylation thus introduces subtle changes in long-range contacts that might lead to significant conformational change of TBK-1. Copyright © 2018 Elsevier Ltd. All rights reserved.
Mechanics of tunable helices and geometric frustration in biomimetic seashells
NASA Astrophysics Data System (ADS)
Guo, Qiaohang; Chen, Zi; Li, Wei; Dai, Pinqiang; Ren, Kun; Lin, Junjie; Taber, Larry A.; Chen, Wenzhe
2014-03-01
Helical structures are ubiquitous in nature and engineering, ranging from DNA molecules to plant tendrils, from sea snail shells to nanoribbons. While the helical shapes in natural and engineered systems often exhibit nearly uniform radius and pitch, helical shell structures with changing radius and pitch, such as seashells and some plant tendrils, add to the variety of this family of aesthetic beauty. Here we develop a comprehensive theoretical framework for tunable helical morphologies, and report the first biomimetic seashell-like structure resulting from mechanics of geometric frustration. In previous studies, the total potential energy is everywhere minimized when the system achieves equilibrium. In this work, however, the local energy minimization cannot be realized because of the geometric incompatibility, and hence the whole system deforms into a shape with a global energy minimum whereby the energy in each segment may not necessarily be locally optimized. This novel approach can be applied to develop materials and devices of tunable geometries with a range of applications in nano/biotechnology.
GdPtPb: A noncollinear antiferromagnet with distorted kagome lattice
Manni, S.; Bud'ko, Sergey L.; Canfield, Paul C.
2017-08-24
In the spirit of searching for Gd-based, frustrated, rare earth magnets, we have found antiferomagnetism (AF) in GdPtPb, which crystallizes in the ZrNiAl-type structure that has a distorted kagome lattice of Gd triangles. Single crystals were grown and investigated using structural, magnetic, transport, and thermodynamic measurements. GdPtPb orders antiferromagnetically at 15.5 K, arguably with a planar, noncollinear structure. The high temperature magnetic susceptibility data reveal an “anti-frustration” behavior having a frustration parameter, |f| = |Θ|/T N = 0.25, which can be explained by mean field theory within a two-sublattice model. Here, the study of the magnetic phase diagram down tomore » T = 1.8K reveals a change of magnetic structure through a metamagnetic transition at around 20 kOe and the disappearance of the AF ordering near 140 kOe. In total, our work indicates that GdPtPb can serve as an example of a planar, noncollinear AF with a distorted kagome magnetic sublattice.« less
van Eerd, Eva Anne Marije; Bech Risør, Mette; Spigt, Mark; Godycki-Cwirko, Maciek; Andreeva, Elena; Francis, Nick; Wollny, Anja; Melbye, Hasse; van Schayck, Onno; Kotz, Daniel
2017-06-23
Smoking cessation is the only effective intervention to slow down the accelerated decline in lung function in smokers with chronic obstructive pulmonary disease. Nevertheless, physicians often do not routinely provide evidence-based smoking cessation treatment to their patients. To understand underlying reasons, we explored how physicians engage in smoking cessation treatment in their chronic obstructive pulmonary disease patients. In total, 21 focus group discussions were held with general practitioners and pulmonologists in seven different countries in Europe and Asia. We generated three themes, whereby some of the issues concerned smokers in general: first, 'physicians' frustration with chronic obstructive pulmonary disease patients who smoke'. These frustrations interfered with the provision of evidence-based treatment and could result in this group of patients being treated unequally. Second: 'physicians' limited knowledge of, and negative beliefs about, smoking cessation treatment'. This hindered treating smokers effectively. Third: 'healthcare organisational factors that influence the use of smoking cessation treatments'. Money and time issues, as well as the failure to regard smoking as a disease, influenced how physicians engaged in smoking cessation treatment. Our results indicate that there is a number of barriers to the provision of effective smoking cessation treatment in patients with chronic obstructive pulmonary disease and smokers in general. Introducing an informative smoking cessation programme, including communication skills and ethical issues, in the vocational and postgraduate medical training may help to address these barriers. This is important in order to increase engagement with smoking cessation treatment and to improve quality of chronic obstructive pulmonary disease care. CHANGING ATTITUDES TO HELP PATIENTS STOP SMOKING: Doctors should be given careful, ethically-informed guidance during medical training to help them to support patients to quit smoking. The most important part of treatment for patients with chronic obstructive pulmonary disease (COPD) is help to stop smoking. However, there is evidence to suggest that doctors don't always motivate COPD patients to quit. Eva Anne Marije van Eerd at Maastrict University, The Netherlands, together with an international team of scientists, conducted focus group interviews with doctors in seven different countries to assess barriers to smoking cessation. They found that doctors' frustration with and negative attitudes towards patients who continued to smoke contributed to poor cessation management and treatment inequalities in some cases. Many doctors also cited a lack of experience with smoking cessation techniques alongside time and money issues as barriers to effective treatment.
NASA Astrophysics Data System (ADS)
Kintz, Natalie M.; Chou, Chih-Ping; Vessey, William B.; Leveton, Lauren B.; Palinkas, Lawrence A.
2016-12-01
Deep space explorations will involve significant delays in communication to and from Earth that will likely impact individual and team outcomes. However, the extent of these impacts and the appropriate countermeasures for their mitigation remain largely unknown. This study utilized the International Space Station (ISS), a high-fidelity analog for deep space, as a research platform to assess the impact of communication delays on individual and team performance, mood, and behavior. Three astronauts on the ISS and 18 mission support personnel performed tasks with and without communication delays (50-s one-way) during a mission lasting 166 days. Self-reported assessments of individual and team performance and mood were obtained after each task. Secondary outcomes included communication quality and task autonomy. Qualitative data from post-mission interviews with astronauts were used to validate and expand on quantitative data, and to elicit recommendations for countermeasures. Crew well-being and communication quality were significantly reduced in communication delay tasks compared to control. Communication delays were also significantly associated with increased individual stress/frustration. Qualitative data suggest communication delays impacted operational outcomes (i.e. task efficiency), teamwork processes (i.e. team/task coordination) and mood (i.e. stress/frustration), particularly when tasks involved high task-related communication demands, either because of poor communication strategies or low crew autonomy. Training, teamwork, and technology-focused countermeasures were identified to mitigate or prevent adverse impacts.
Interaction of multiferroic properties and interfaces in hexagonal LuMnO3 ceramics
NASA Astrophysics Data System (ADS)
Baghizadeh, A.; Vieira, J. M.; Stroppa, D. G.; Mirzadeh Vaghefi, P.; Graça, M. P.; Amaral, J. S.; Willinger, M.-G.; Amaral, V. S.
2017-02-01
A study on the underlying interaction mechanisms between lattice constants, magnetic and dielectric properties with inhomogeneities or internal interfaces in hexagonal, off-stoichiometric LuMnO3 oxide is presented. By increasing Mn content the a-axis constant and volume of the unit cell, the antiferromagnetic (AFM) Néel temperature, T N, and frustration factor of the frustrated Mn3+ trimmers in basal plane show decreasing trends. It was found that increasing the annealing time improves the properties of the lattices and progressively eliminates secondary phases for compositions within the solid solution stability limits. A magnetic contribution below T N is observed for all samples. Two regimes of magnetization below and above 45 K were observed in the AFM state. The magnetic contribution below T N is assigned to either the secondary phase or internal interfaces like ferroelectric (FE) domain walls. Magneto-dielectric coupling at T N is preserved in off-stoichiometric ceramics. The presence of a low temperature anomaly of the dielectric constant is correlated to the composition of the solid solution in off-stoichiometric ceramics. Large FE domains are observed in piezoresponse force microscopy (PFM) images of doped and un-doped ceramics, whereas atomic structure analysis indicates the parallel formation of nano-sized FE domains. A combination of measured properties and microscopy images of micron- and nano-sized domains ascertain the role of lattice distortion and stability of solid solution on multiferroic properties.
Lindström, Ida; Dogan, Jakob
2018-05-18
Intrinsically disordered proteins (IDPs) are abundant in the eukaryotic proteome. However, little is known about the role of subnanosecond dynamics and the conformational entropy that it represents in protein-protein interactions involving IDPs. Using nuclear magnetic resonance side chain and backbone relaxation, stopped-flow kinetics, isothermal titration calorimetry, and computational studies, we have characterized the interaction between the globular TAZ1 domain of the CREB binding protein and the intrinsically disordered transactivation domain of STAT2 (TAD-STAT2). We show that the TAZ1/TAD-STAT2 complex retains considerable subnanosecond motions, with TAD-STAT2 undergoing only a partial disorder-to-order transition. We report here the first experimental determination of the conformational entropy change for both binding partners in an IDP binding interaction and find that the total change even exceeds in magnitude the binding enthalpy and is comparable to the contribution from the hydrophobic effect, demonstrating its importance in the binding energetics. Furthermore, we show that the conformational entropy change for TAZ1 is also instrumental in maintaining a biologically meaningful binding affinity. Strikingly, a spatial clustering of very high amplitude motions and a cluster of more rigid sites in the complex exist, which through computational studies we found to overlap with regions that experience energetic frustration and are less frustrated, respectively. Thus, the residual dynamics in the bound state could be necessary for faster dissociation, which is important for proteins that interact with multiple binding partners.
2012-01-01
Background Frustrated phagocytosis has been stated as an important factor in the initiation of an inflammatory response after fibre exposure. The length of fibrous structures has been linked to the potential of fibres to induce adverse health effects for at least 40 years. However, we only recently reported for the first time the threshold length for fibre-induced inflammation in the pleural space and we implicated frustrated phagocytosis in the pro-inflammatory effects of long fibres. This study extends the examination of the threshold value for frustrated phagocytosis using well-defined length classes of silver nanowires (AgNW) ranging from 3–28 μm and describes in detail the morphology of frustrated phagocytosis using a novel technique and also describes compartmentalisation of fibres in the pleural space. Methods A novel technique, backscatter scanning electron microscopy (BSE) was used to study frustrated phagocytosis since it provides high-contrast detection of nanowires, allowing clear discrimination between the nanofibres and other cellular features. A human monocyte-derived macrophage cell line THP-1 was used to investigate cell-nanowire interaction in vitro and the parietal pleura, the site of fibre retention after inhalation exposure was chosen to visualise the cell- fibre interaction in vivo after direct pleural installation of AgNWs. Results The length cut-off value for frustrated phagocytosis differs in vitro and in vivo. While in vitro frustrated phagocytosis could be observed with fibres ≥14 μm, in vivo studies showed incomplete uptake at a fibre length of ≥10 μm. Recently we showed that inflammation in the pleural space after intrapleural injection of the same nanofibre panel occurs at a length of ≥5 μm. This onset of inflammation does not correlate with the onset of frustrated phagocytosis as shown in this study, leading to the conclusion that intermediate length fibres fully enclosed within macrophages as well as frustrated phagocytosis are associated with a pro-inflammatory state in the pleural space. We further showed that fibres compartmentalise in the mesothelial cells at the parietal pleura as well as in inflammatory cells in the pleural space. Conclusion BSE is a useful way to clearly distinguish between fibres that are, or are not, membrane-bounded. Using this method we were able to show differences in the threshold length at which frustrated phagocytosis occurred between in vitro and in vivo models. Visualising nanowires in the pleura demonstrated at least 2 compartments – in leukocyte aggregations and in the mesothelium - which may have consequences for long term pathology in the pleural space including mesothelioma. PMID:22929371
Hole pairing and thermodynamic properties of the two dimensional frustrated t-J model
NASA Astrophysics Data System (ADS)
Roy, K.; Pal, P.; Nath, S.; Ghosh, N. K.
2018-04-01
The frustrated t-J model is investigated by using the exact-diagonalization (ED) method on an 8-site cluster. The effect on next-nearest-neighbor (NNN) exchange interaction J' (frustration) on the hole pairing and the thermodynamic properties of the system is considered. Two holes initially remain unbound at smaller value of J'/t, but tend to bind at larger value. The maximum possibility of pair formation has been observed to be at NNN sites. Entropy calculation shows that the system goes to more disordered state with J'. The specific heat curves show a single peak structure. A decrease in effective exchange energy is observed due to the frustration.
Classical Magnetic Frustration
NASA Astrophysics Data System (ADS)
Tsao, Eugene; Henriksen, Erik
We report on studies of classical magnetic frustration, inspired by Mellado et al., by studying an ensemble of freely rotating magnets, made of 1'' rare-earth bar magnets press-fit into polypropylene spheres floating on air bearings. The magnets can be arranged in any configuration to study frustration in 1, 2, or 3 dimensions. For instance, arranged in a Kagome lattice the magnets show an absence of high-energy in-in-in and out-out-out states; the presence of multiple ground states is indicative of macroscopic frustration. We also observe classical ``magnon'' transport in a one-dimensional chain. We will report on progress made in exploring the behavior of these magnets in triangular, Kagome, and honeycomb lattice configurations.
Acid-base chemistry of frustrated water at protein interfaces.
Fernández, Ariel
2016-01-01
Water molecules at a protein interface are often frustrated in hydrogen-bonding opportunities due to subnanoscale confinement. As shown, this condition makes them behave as a general base that may titrate side-chain ammonium and guanidinium cations. Frustration-based chemistry is captured by a quantum mechanical treatment of proton transference and shown to remove same-charge uncompensated anticontacts at the interface found in the crystallographic record and in other spectroscopic information on the aqueous interface. Such observations are untenable within classical arguments, as hydronium is a stronger acid than ammonium or guanidinium. Frustration enables a directed Grotthuss mechanism for proton transference stabilizing same-charge anticontacts. © 2015 Federation of European Biochemical Societies.
Perkins, Elizabeth B; Oser, Carrie B
2014-06-01
Substance abuse counselors who work with offenders are facing increasing caseloads, which puts them at higher risk of job frustration. The purpose of this study was to explore differences between substance abuse counselors employed in prison versus community settings in terms of level of organizational support and job frustration. This study also investigated whether organizational support was associated with job frustration after controlling for counselor characteristics and workplace setting. This was accomplished utilizing data that were collected from 267 counselors as part of the Criminal Justice Drug Abuse Treatment Studies research cooperative. Results indicated that counselors employed in community settings, as compared with those employed in prisons, are more likely to report higher levels of perceived organizational support. In addition, ordinal logistic regression results reveal that counselors who are non-White and have greater levels of organizational support have less job frustration, after controlling for counselor characteristics and workplace setting. The researches to practice implications are discussed.
The allure of the forbidden: breaking taboos, frustration, and attraction to violent video games.
Whitaker, Jodi L; Melzer, André; Steffgen, Georges; Bushman, Brad J
2013-04-01
Although people typically avoid engaging in antisocial or taboo behaviors, such as cheating and stealing, they may succumb in order to maximize their personal benefit. Moreover, they may be frustrated when the chance to commit a taboo behavior is withdrawn. The present study tested whether the desire to commit a taboo behavior, and the frustration from being denied such an opportunity, increases attraction to violent video games. Playing violent games allegedly offers an outlet for aggression prompted by frustration. In two experiments, some participants had no chance to commit a taboo behavior (cheating in Experiment 1, stealing in Experiment 2), others had a chance to commit a taboo behavior, and others had a withdrawn chance to commit a taboo behavior. Those in the latter group were most attracted to violent video games. Withdrawing the chance for participants to commit a taboo behavior increased their frustration, which in turn increased their attraction to violent video games.
Perkins, Elizabeth B.; Oser, Carrie B.
2014-01-01
Substance abuse counselors who work with offenders are facing increasing caseloads which puts them at higher risk for job frustration. The purpose of this study was to explore differences between substance abuse counselors employed in prison versus community settings in terms of level of organizational support and job frustration. This study also investigated whether organizational support was associated with job frustration after controlling for counselor characteristics and workplace setting. This was accomplished utilizing data that was collected from 267 counselors as part of the Criminal Justice Drug Abuse Treatment Studies (CJ-DATS) research cooperative. Results indicated that counselors employed in community settings, as compared to those employed in prisons, are more likely to report higher levels of perceived organizational support. In addition, ordinal logistic regression results reveal that counselors who are non-white and have greater levels of organizational support have less job frustration, after controlling for counselor characteristics and workplace setting. The research to practice implications are discussed. PMID:23525175
Charge frustration in complex fluids and in electronic systems
NASA Astrophysics Data System (ADS)
Carraro, Carlo
1997-02-01
The idea of charge frustration is applied to describe the properties of such diverse physical systems as oil-water-surfactant mixtures and metal-ammonia solutions. The minimalist charge-frustrated model possesses one energy scale and two length scales. For oil-water-surfactant mixtures, these parameters have been determined starting from the microscopic properties of the physical systems under study. Thus, microscopic properties are successfully related to the observed mesoscopic structure.
Cornman, Jennifer C.; Freedman, Vicki A.
2016-01-01
Objectives. We evaluate (a) associations between marital quality (emotional support, strain, and overall appraisal) and three negative aspects of experienced well-being (frustration, sadness, and worry) among older husbands and wives and (b) the relative importance of own versus spouse’s marital quality assessments for understanding experienced well-being in later life. Method. Data are from the 2009 Disability and Use of Time daily diary supplement to the Panel Study of Income Dynamics (N = 722). We estimate actor–partner interdependence models, using seemingly unrelated regression. Results. Own reports of marital strain are associated with own frustration, sadness, and worry among wives and are associated with frustration only among husbands. Own reports of marital support are associated with negative emotion among husbands only: higher levels of marital support are associated with less worry. Results from partner effects analyses also are mixed. Husbands’ reports of marital strain are associated with wives’ elevated frustration levels, whereas wives’ reports of greater marital support are associated with their husbands’ higher frustration levels. Discussion. One’s own and spouse’s marital appraisals play a complex role in shaping negative emotions among older adults. Findings suggest that frustration is a particularly complex emotion and a promising area for further study among older married couples. PMID:26329115
Localized structural frustration for evaluating the impact of sequence variants
Kumar, Sushant; Clarke, Declan; Gerstein, Mark
2016-01-01
Population-scale sequencing is increasingly uncovering large numbers of rare single-nucleotide variants (SNVs) in coding regions of the genome. The rarity of these variants makes it challenging to evaluate their deleteriousness with conventional phenotype–genotype associations. Protein structures provide a way of addressing this challenge. Previous efforts have focused on globally quantifying the impact of SNVs on protein stability. However, local perturbations may severely impact protein functionality without strongly disrupting global stability (e.g. in relation to catalysis or allostery). Here, we describe a workflow in which localized frustration, quantifying unfavorable local interactions, is employed as a metric to investigate such effects. Using this workflow on the Protein Databank, we find that frustration produces many immediately intuitive results: for instance, disease-related SNVs create stronger changes in localized frustration than non-disease related variants, and rare SNVs tend to disrupt local interactions to a larger extent than common variants. Less obviously, we observe that somatic SNVs associated with oncogenes and tumor suppressor genes (TSGs) induce very different changes in frustration. In particular, those associated with TSGs change the frustration more in the core than the surface (by introducing loss-of-function events), whereas those associated with oncogenes manifest the opposite pattern, creating gain-of-function events. PMID:27915290
Maternal responses to child frustration and requests for help in dyads with fragile X syndrome.
Wheeler, A C; Hatton, D; Holloway, V T; Sideris, J; Neebe, E C; Roberts, J E; Reznick, J S
2010-06-01
Variability in behaviour displayed by children with fragile X syndrome (FXS) may be partially attributable to environmental factors such as maternal responsivity. The purpose of this study was to explore variables associated with maternal behaviour during a task designed to elicit frustration in their children with FXS. Forty-six mother-child dyads, in which the child had full-mutation FXS, were observed in their homes during a task designed to elicit frustration in the child. Each child was given a wrong set of keys and asked to open a box to retrieve a desired toy. Mothers were provided with the correct set of keys and instructed to intervene when they perceived their child was getting too frustrated. Child-expressed frustration and requests for help and maternal behaviours (comforting, negative control, and encouraging/directing) were observed and coded. Maternal variables (e.g. depression, stress, education levels), child variables (e.g. autistic behaviours, age, medication use) and child behaviours (frustration, requests for help) were explored as predictors of maternal behaviour. Almost all mothers intervened to help their children and most used encouraging/directing behaviours, whereas very few used comforting or negative control. Child age and child behaviours during the frustrating event were significant predictors of encouraging/directing behaviours in the mothers. Children whose mothers reported higher depressive symptomology used fewer requests for help, and mothers of children with more autistic behaviours used more negative control. The results of this study suggest that child age and immediate behaviours are more strongly related to maternal responsivity than maternal traits such as depression and stress.
Geometric Magnetic Frustration in Li3Mg2OsO6 Studied with Muon Spin Relaxation
NASA Astrophysics Data System (ADS)
Carlo, J. P.; Derakhshan, S.; Greedan, J. E.
Geometric frustration manifests when the spatial arrangement of ions inhibits magnetic order. Typically associated with antiferromagnetically (AF)-correlated moments on triangular or tetrahedral lattices, frustration occurs in a variety of structures and systems, resulting in rich phase diagrams and exotic ground states. As a window to exotic physics revealed by the cancellation of normally dominant interactions, the research community has taken great interest in frustrated systems. One family of recent interest are the rock-salt ordered oxides A5BO6, in which the B sites are occupied by magnetic ions comprising a network of interlocked tetrahedra, and nonmagnetic ions on the A sites control the B oxidation state through charge neutrality. Here we will discuss studies of Li3Mg2OsO6 using muon spin relaxation (μSR), a highly sensitive local probe of magnetism. Previous studies of this family included Li5OsO6, which exhibits AF order below 50K with minimal evidence for frustration, and Li4MgReO6, which exhibits glassy magnetism. Li3Mg2RuO6, meanwhile, exhibits long-range AF, with the ordering temperature suppressed by frustration. But its isoelectronic twin, Li3Mg2OsO6 (5d3 vs. 4d3) exhibits very different behavior, revealed by μSR to be a glassy ground state below 12K. Understanding why such similar systems exhibit diverse ground-state behavior is key to understanding the nature of geometric magnetic frustration. Financial support from the Research Corporation for Science Advancement.
Frustrations among graduates of athletic training education programs.
Bowman, Thomas G; Dodge, Thomas M
2013-01-01
Although previous researchers have begun to identify sources of athletic training student stress, the specific reasons for student frustrations are not yet fully understood. It is important for athletic training administrators to understand sources of student frustration to provide a supportive learning environment. To determine the factors that lead to feelings of frustration while completing a professional athletic training education program (ATEP). Qualitative study. National Athletic Trainers' Association (NATA) accredited postprofessional education program. Fourteen successful graduates (12 women, 2 men) of accredited professional undergraduate ATEPs enrolled in an NATA-accredited postprofessional education program. We conducted semistructured interviews and analyzed data with a grounded theory approach using open, axial, and selective coding procedures. We negotiated over the coding scheme and performed peer debriefings and member checks to ensure trustworthiness of the results. Four themes emerged from the data: (1) Athletic training student frustrations appear to stem from the amount of stress involved in completing an ATEP, leading to anxiety and feelings of being overwhelmed. (2) The interactions students have with classmates, faculty, and preceptors can also be a source of frustration for athletic training students. (3) Monotonous clinical experiences often left students feeling disengaged. (4) Students questioned entering the athletic training profession because of the fear of work-life balance problems and low compensation. In order to reduce frustration, athletic training education programs should validate students' decisions to pursue athletic training and validate their contributions to the ATEP; provide clinical education experiences with graded autonomy; encourage positive personal interactions between students, faculty, and preceptors; and successfully model the benefits of a career in athletic training.
Global issues from an African point of view. 7th International Women and Health Meeting in Uganda.
Shallat, L
1993-01-01
The seventh International Women and Health Meeting (IWHM) was held in Kampala, Uganda, during September 12-17, 1993. The purpose of the meeting was to devise strategies to confront such issues as the impact of economic policies on women's health, the implementation of reproductive rights, population control and policies, contraceptive technologies, AIDS, and sexual abuse and violence. In addition to these topics, discussion centered on interaction with the upcoming 1994 International Conference on Population and Development. Some participants were frustrated, however, by the procedural problems that prevented creation of a cohesive position paper and left important strategic questions unanswered. Women from Latin America and the Caribbean were kept from full participation by the lack of a Spanish translator but nevertheless held an information session on regional developments in abortion reform and population policy. These women were also successful in their bid to host the eighth IWHM in Brazil in 1996.
Debunking Health IT Usability Myths
Staggers, N.; Xiao, Y.; Chapman, L.
2013-01-01
Poor usability is a threat to patient safety and linked to productivity loss, workflow disruption, user frustration, sub-optimal product use and system de-installations. Although usability is receiving more attention nationally and internationally, myths about usability persist. This editorial debunks five common myths about usability (1) usability only concerns the look and feel of a product and is, therefore, only a minor concern, (2) usability is not measurable, (3) usability stifles innovation, (4) vendors are solely responsible for product usability, and (5) usability methods are not practical for use in healthcare. PMID:23874361
Assessment of Psychological and Psycho-physiological Problems Among Visually Impaired Adolescents
Bhuvaneswari, Mohanraj; Immanuel Selvaraj, Chinnadurai; Selvaraj, Balakrishnan; Srinivasan, Thiruvengadam
2016-01-01
Background: Visual impairment tends to evoke more discomfiture than any other disability. Primarily, the biggest issue may be that blindness is visible. Furthermore, visual impairment develops serious medical, psychological, social and economic problems. Objectives: The focus of the current study was to investigate the psychological and psycho physiological problems of visually impaired adolescent students. Patients and Methods: Purposive sampling was adopted to select 150 visually impaired students (71 males and 72 females) from five schools in Coimbatore city of the Tamil Nadu state, India. Anxiety, frustration, aggression and social and personal adjustment levels of the visually impaired students were measured in this study using Taylor’s manifest anxiety scale, frustration test, aggression scale and the adolescent adjustment inventory, respectively. Results: Anxiety (χ2 = 185.66, P = 0 at P < 0.01), frustration (χ2 = 167.23, P = 0 at P < 0.01) and aggression (χ2 = 57.66, P = 0 at P < 0.01) were significantly related to adjustment among visually impaired students. The adjustment score had a significant positive correlation with anxiety (r = 0.919, P = 0 at P < 0.01), frustration (r = 0.887, P = 0 at P < 0.01) and aggression levels (r = 0.664, P = 0 at P < 0.01), anxiety was significantly correlated with frustration (r = 0. 961, P = 0 at P < 0.01) and aggression levels (r = 0.727, P < 0.01) and frustration was significantly correlated with aggression level (r = 0. 637, P = 0 at P < 0.01) of visually impaired adolescents. There was a positive relationship between psycho-physiological disorders and anxiety frustration, aggression and adjustment among visually impaired students. Conclusions: Visually impaired students exhibited significant levels of psychological and psycho-physiological problems. PMID:27284280
Grabell, Adam S; Li, Yanwei; Barker, Jeff W; Wakschlag, Lauren S; Huppert, Theodore J; Perlman, Susan B
2018-01-01
Burgeoning interest in early childhood irritability has recently turned toward neuroimaging techniques to better understand normal versus abnormal irritability using dimensional methods. Current accounts largely assume a linear relationship between poor frustration management, an expression of irritability, and its underlying neural circuitry. However, the relationship between these constructs may not be linear (i.e., operate differently at varying points across the irritability spectrum), with implications for how early atypical irritability is identified and treated. Our goal was to examine how the association between frustration-related lateral prefrontal cortex (LPFC) activation and irritability differs across the dimensional spectrum of irritability by testing for non-linear associations. Children (N = 92; ages 3-7) ranging from virtually no irritability to the upper end of the clinical range completed a frustration induction task while we recorded LPFC hemoglobin levels using fNIRS. Children self-rated their emotions during the task and parents rated their child's level of irritability. Whereas a linear model showed no relationship between frustration-related LPFC activation and irritability, a quadratic model revealed frustration-related LPFC activation increased as parent-reported irritability scores increased within the normative range of irritability but decreased with increasing irritability in the severe range, with an apex at the 91st percentile. Complementarily, we found children's self-ratings of emotion during frustration related to concurrent LPFC activation as an inverted U function, such that children who reported mild distress had greater activation than peers reporting no or high distress. Results suggest children with relatively higher irritability who are unimpaired may possess well-developed LPFC support, a mechanism that drops out in the severe end of the irritability dimension. Findings suggest novel avenues for understanding the heterogeneity of early irritability and its clinical sequelae.
Frustrations Among Graduates of Athletic Training Education Programs
Bowman, Thomas G; Dodge, Thomas M
2013-01-01
Context Although previous researchers have begun to identify sources of athletic training student stress, the specific reasons for student frustrations are not yet fully understood. It is important for athletic training administrators to understand sources of student frustration to provide a supportive learning environment. Objective To determine the factors that lead to feelings of frustration while completing a professional athletic training education program (ATEP). Design Qualitative study. Setting National Athletic Trainers' Association (NATA) accredited postprofessional education program. Patients or Other Participants Fourteen successful graduates (12 women, 2 men) of accredited professional undergraduate ATEPs enrolled in an NATA-accredited postprofessional education program. Data Collection and Analysis We conducted semistructured interviews and analyzed data with a grounded theory approach using open, axial, and selective coding procedures. We negotiated over the coding scheme and performed peer debriefings and member checks to ensure trustworthiness of the results. Results Four themes emerged from the data: (1) Athletic training student frustrations appear to stem from the amount of stress involved in completing an ATEP, leading to anxiety and feelings of being overwhelmed. (2) The interactions students have with classmates, faculty, and preceptors can also be a source of frustration for athletic training students. (3) Monotonous clinical experiences often left students feeling disengaged. (4) Students questioned entering the athletic training profession because of the fear of work-life balance problems and low compensation. Conclusions In order to reduce frustration, athletic training education programs should validate students' decisions to pursue athletic training and validate their contributions to the ATEP; provide clinical education experiences with graded autonomy; encourage positive personal interactions between students, faculty, and preceptors; and successfully model the benefits of a career in athletic training. PMID:23672328
Geometric magnetic frustration in RE{sub 2}O{sub 2}S oxysulfides (RE = Sm, Eu and Gd)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Biondo, V.; Sarvezuk, P.W.C.; Ivashita, F.F.
2014-06-01
Graphical abstract: Stacked planes in the <001> direction of an oxysulfide structure, showing the triangular nets formed by rare earth cations, which moments present geometric magnetic frustration. - Highlights: • We prepared monophasic RE{sub 2}O{sub 2}S Oxysulfides (RE = Sm, Eu and Gd). • RE{sub 2}O{sub 2}S compounds were characterized regarding structural and magnetic properties. • Mössbauer spectra were obtained for Eu{sub 2}O{sub 2}S and Gd{sub 2}O{sub 2}S at different temperatures. • Oxysulfides present geometric magnetic frustration of the rare-earth sublattice. - Abstract: RE{sub 2}O{sub 2}S oxysulfides (with RE = Sm, Eu and Gd) were prepared and characterized regarding theirmore » structural and magnetic properties. The compounds crystallized in the trigonal symmetry (space group P-3m/D{sub 3}{sup 3}d), with the lattice parameter varying linearly with the ionic radius of the RE cation. All these oxysulfides are magnetically frustrated and only the gadolinium sample showed magnetic order down to 3 K. The magnetic frustration is attributed to the spatial distribution of cations over the lattice, where the RE’s magnetic moments occupy the sites forming a triangular plane lattice, perpendicular to the direction. This geometric magnetic frustration was firstly recognized for these oxysulfides.« less
Emergent inequality and self-organized social classes in a network of power and frustration
Mahault, Benoit; Saxena, Avadh; Nisoli, Cristiano
2017-02-17
We propose a simple agent-based model on a network to conceptualize the allocation of limited wealth among more abundant expectations at the interplay of power, frustration, and initiative. Concepts imported from the statistical physics of frustrated systems in and out of equilibrium allow us to compare subjective measures of frustration and satisfaction to collective measures of fairness in wealth distribution, such as the Lorenz curve and the Gini index. We find that a completely libertarian, law-of-the-jungle setting, where every agent can acquire wealth from or lose wealth to anybody else invariably leads to a complete polarization of the distribution ofmore » wealth vs. opportunity. This picture is however dramatically ameliorated when hard constraints are imposed over agents in the form of a limiting network of transactions. There, an out of equilibrium dynamics of the networks, based on a competition between power and frustration in the decision-making of agents, leads to network coevolution. The ratio of power and frustration controls different dynamical regimes separated by kinetic transitions and characterized by drastically different values of equality. It also leads, for proper values of social initiative, to the emergence of three self-organized social classes, lower, middle, and upper class. Their dynamics, which appears mostly controlled by the middle class, drives a cyclical regime of dramatic social changes.« less
Emergent inequality and self-organized social classes in a network of power and frustration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mahault, Benoit; Saxena, Avadh; Nisoli, Cristiano
We propose a simple agent-based model on a network to conceptualize the allocation of limited wealth among more abundant expectations at the interplay of power, frustration, and initiative. Concepts imported from the statistical physics of frustrated systems in and out of equilibrium allow us to compare subjective measures of frustration and satisfaction to collective measures of fairness in wealth distribution, such as the Lorenz curve and the Gini index. We find that a completely libertarian, law-of-the-jungle setting, where every agent can acquire wealth from or lose wealth to anybody else invariably leads to a complete polarization of the distribution ofmore » wealth vs. opportunity. This picture is however dramatically ameliorated when hard constraints are imposed over agents in the form of a limiting network of transactions. There, an out of equilibrium dynamics of the networks, based on a competition between power and frustration in the decision-making of agents, leads to network coevolution. The ratio of power and frustration controls different dynamical regimes separated by kinetic transitions and characterized by drastically different values of equality. It also leads, for proper values of social initiative, to the emergence of three self-organized social classes, lower, middle, and upper class. Their dynamics, which appears mostly controlled by the middle class, drives a cyclical regime of dramatic social changes.« less
Emergent inequality and self-organized social classes in a network of power and frustration
Mahault, Benoit; Saxena, Avadh
2017-01-01
We propose a simple agent-based model on a network to conceptualize the allocation of limited wealth among more abundant expectations at the interplay of power, frustration, and initiative. Concepts imported from the statistical physics of frustrated systems in and out of equilibrium allow us to compare subjective measures of frustration and satisfaction to collective measures of fairness in wealth distribution, such as the Lorenz curve and the Gini index. We find that a completely libertarian, law-of-the-jungle setting, where every agent can acquire wealth from or lose wealth to anybody else invariably leads to a complete polarization of the distribution of wealth vs. opportunity. This picture is however dramatically ameliorated when hard constraints are imposed over agents in the form of a limiting network of transactions. There, an out of equilibrium dynamics of the networks, based on a competition between power and frustration in the decision-making of agents, leads to network coevolution. The ratio of power and frustration controls different dynamical regimes separated by kinetic transitions and characterized by drastically different values of equality. It also leads, for proper values of social initiative, to the emergence of three self-organized social classes, lower, middle, and upper class. Their dynamics, which appears mostly controlled by the middle class, drives a cyclical regime of dramatic social changes. PMID:28212440
Effects of user mental state on EEG-BCI performance.
Myrden, Andrew; Chau, Tom
2015-01-01
Changes in psychological state have been proposed as a cause of variation in brain-computer interface performance, but little formal analysis has been conducted to support this hypothesis. In this study, we investigated the effects of three mental states-fatigue, frustration, and attention-on BCI performance. Twelve able-bodied participants were trained to use a two-class EEG-BCI based on the performance of user-specific mental tasks. Following training, participants completed three testing sessions, during which they used the BCI to play a simple maze navigation game while periodically reporting their perceived levels of fatigue, frustration, and attention. Statistical analysis indicated that there is a significant relationship between frustration and BCI performance while the relationship between fatigue and BCI performance approached significance. BCI performance was 7% lower than average when self-reported fatigue was low and 7% higher than average when self-reported frustration was moderate. A multivariate analysis of mental state revealed the presence of contiguous regions in mental state space where BCI performance was more accurate than average, suggesting the importance of moderate fatigue for achieving effortless focus on BCI control, frustration as a potential motivating factor, and attention as a compensatory mechanism to increasing frustration. Finally, a visual analysis showed the sensitivity of underlying class distributions to changes in mental state. Collectively, these results indicate that mental state is closely related to BCI performance, encouraging future development of psychologically adaptive BCIs.
Localized structural frustration for evaluating the impact of sequence variants.
Kumar, Sushant; Clarke, Declan; Gerstein, Mark
2016-12-01
Population-scale sequencing is increasingly uncovering large numbers of rare single-nucleotide variants (SNVs) in coding regions of the genome. The rarity of these variants makes it challenging to evaluate their deleteriousness with conventional phenotype-genotype associations. Protein structures provide a way of addressing this challenge. Previous efforts have focused on globally quantifying the impact of SNVs on protein stability. However, local perturbations may severely impact protein functionality without strongly disrupting global stability (e.g. in relation to catalysis or allostery). Here, we describe a workflow in which localized frustration, quantifying unfavorable local interactions, is employed as a metric to investigate such effects. Using this workflow on the Protein Databank, we find that frustration produces many immediately intuitive results: for instance, disease-related SNVs create stronger changes in localized frustration than non-disease related variants, and rare SNVs tend to disrupt local interactions to a larger extent than common variants. Less obviously, we observe that somatic SNVs associated with oncogenes and tumor suppressor genes (TSGs) induce very different changes in frustration. In particular, those associated with TSGs change the frustration more in the core than the surface (by introducing loss-of-function events), whereas those associated with oncogenes manifest the opposite pattern, creating gain-of-function events. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.
Emergent inequality and self-organized social classes in a network of power and frustration.
Mahault, Benoit; Saxena, Avadh; Nisoli, Cristiano
2017-01-01
We propose a simple agent-based model on a network to conceptualize the allocation of limited wealth among more abundant expectations at the interplay of power, frustration, and initiative. Concepts imported from the statistical physics of frustrated systems in and out of equilibrium allow us to compare subjective measures of frustration and satisfaction to collective measures of fairness in wealth distribution, such as the Lorenz curve and the Gini index. We find that a completely libertarian, law-of-the-jungle setting, where every agent can acquire wealth from or lose wealth to anybody else invariably leads to a complete polarization of the distribution of wealth vs. opportunity. This picture is however dramatically ameliorated when hard constraints are imposed over agents in the form of a limiting network of transactions. There, an out of equilibrium dynamics of the networks, based on a competition between power and frustration in the decision-making of agents, leads to network coevolution. The ratio of power and frustration controls different dynamical regimes separated by kinetic transitions and characterized by drastically different values of equality. It also leads, for proper values of social initiative, to the emergence of three self-organized social classes, lower, middle, and upper class. Their dynamics, which appears mostly controlled by the middle class, drives a cyclical regime of dramatic social changes.
... which can led to embarrassment and frustration or bullying, teasing, or avoidance in school and other social ... which can led to embarrassment and frustration or bullying, teasing, or avoidance in school and other social ...
NASA Astrophysics Data System (ADS)
Ghosh, Urbi
An important question in online learning involves how to effectively motivate and retain students in science online courses. There is a dearth of research and knowledge about the experiences of students enrolled in online science courses in community colleges which has impeded the proper development and implementation of online courses and retention of students in the online environment. This study sought to provide an understanding of the relationships among each of the following variables: self-efficacy, task value, negative-achievement emotions, self-regulation learning strategies (metacognition), learning strategy (elaboration), and course satisfaction to student's performance (course final grade). Bandura's social-cognitive theory was used as a framework to describe the relationships among students' motivational beliefs (perceived task value, self-efficacy, and self-regulation) and emotions (frustration and boredom) with the dependent variables (elaboration and overall course satisfaction). A mixed-method design was used with a survey instrumentation and student interviews. A variety of science online courses in biology, genetics, astronomy, nutrition, and chemistry were surveyed in two community colleges. Community colleges students (N = 107) completed a questionnaire during enrollment in a variety of online science online courses. Upon course completion, 12 respondents were randomly selected for follow-up in-depth interviews. Multiple regression results from the study indicate perceived task value and self-regulatory learning strategies (metacognition) were as important predictors for students' use of elaboration, while self-efficacy and the number of prior online courses was not significant predictors for students' elaboration when all four predictors were included. Frustration was a significant negative predictor of overall course satisfaction, and boredom unexpectedly emerged as a positive predictor when frustration was also in the model. In addition, the correlations indicated that elaboration and overall course satisfaction were not significantly related to participants' course grade (performance). Furthermore, five major themes emerged from the students' experiences: the role of personal dispositions, academic challenge, self-regulated learning, student communication, and the negative emotions that shaped student experiences. In particular, negative emotions most experienced by students were found to be anxiety, stress, frustration and confusion. In total, results from this study implicate an important role of emotions such as frustration in students' overall course satisfaction and the importance of task value. Students' career aspirations and direct use of the course content were more likely to report greater use of elaboration strategies. Finally, this research also found that students self-regulated their learning in the online environment on a variety of levels.
NASA Astrophysics Data System (ADS)
Loh, Y. L.; Yao, D. X.; Carlson, E. W.
2008-04-01
A new class of two-dimensional magnetic materials Cu9X2(cpa)6ṡxH2O ( cpa=2 -carboxypentonic acid; X=F,Cl,Br ) was recently fabricated in which Cu sites form a triangular kagome lattice (TKL). As the simplest model of geometric frustration in such a system, we study the thermodynamics of Ising spins on the TKL using exact analytic method as well as Monte Carlo simulations. We present the free energy, internal energy, specific heat, entropy, sublattice magnetizations, and susceptibility. We describe the rich phase diagram of the model as a function of coupling constants, temperature, and applied magnetic field. For frustrated interactions in the absence of applied field, the ground state is a spin liquid phase with residual entropy per spin s0/kB=(1)/(9)ln72≈0.4752… . In weak applied field, the system maps to the dimer model on a honeycomb lattice, with residual entropy 0.0359 per spin and quasi-long-range order with power-law spin-spin correlations that should be detectable by neutron scattering. The power-law correlations become exponential at finite temperatures, but the correlation length may still be long.
Exchange bias effect in CoAl2O4
NASA Astrophysics Data System (ADS)
Mohanty, Prachi; Marik, Sourav; Singh, Ravi P.
2018-04-01
Herein, we report the appearance of a significant exchange bias (EB) effect for the highly frustrated spinel material CoAl2O4. It shows a large value of frustration parameter as observed from the dc susceptibility measurements. CoAl2O4 exhibits the exchange bias effect below 8 K when it is cooled in the presence of a magnetic field. Detailed magnetization measurements indicate that the exchange bias properties of this compound are associated with the frustration present in this material.
Multipartite entanglement and frustration
NASA Astrophysics Data System (ADS)
Facchi, P.; Florio, G.; Marzolino, U.; Parisi, G.; Pascazio, S.
2010-02-01
Some features of the global entanglement of a composed quantum system can be quantified in terms of the purity of a balanced bipartition, made up of half of its subsystems. For the given bipartition, purity can always be minimized by taking a suitable (pure) state. When many bipartitions are considered, the requirement that purity be minimal for all bipartitions can engender conflicts and frustration will arise. This unearths an interesting link between frustration and multipartite entanglement, defined as the average purity over all (balanced) bipartitions.
Frustrated honeycomb-lattice bilayer quantum antiferromagnet in a magnetic field
NASA Astrophysics Data System (ADS)
Krokhmalskii, Taras; Baliha, Vasyl; Derzhko, Oleg; Schulenburg, Jörg; Richter, Johannes
2018-05-01
Frustrated bilayer quantum magnets have attracted attention as flat-band spin systems with unconventional thermodynamic properties. We study the low-temperature properties of a frustrated honeycomb-lattice bilayer spin-1/2 isotropic (XXX) Heisenberg antiferromagnet in a magnetic field by means of an effective low-energy theory using exact diagonalizations and quantum Monte Carlo simulations. Our main focus is on the magnetization curve and the temperature dependence of the specific heat indicating a finite-temperature phase transition in high magnetic fields.
Appraisal and coping styles account for the effects of temperament on preadolescent adjustment
Thompson, Stephanie F.; Zalewski, Maureen; Lengua, Liliana J.
2014-01-01
Temperament, appraisal, and coping are known to underlie emotion regulation, yet less is known about how these processes relate to each other across time. We examined temperamental fear, frustration, effortful control, and impulsivity, positive and threat appraisals, and active and avoidant coping as processes underpinning the emotion regulation of pre-adolescent children managing stressful events. Appraisal and coping styles were tested as mediators of the longitudinal effects of temperamental emotionality and self-regulation on adjustment using a community sample (N=316) of preadolescent children (8–12 years at T1) studied across one year. High threat appraisals were concurrently related to high fear and impulsivity, whereas effortful control predicted relative decreases in threat appraisal. High fear was concurrently related to high positive appraisal, and impulsivity predicted increases in positive appraisal. Fear was concurrently related to greater avoidant coping, and impulsivity predicted increases in avoidance. Frustration predicted decreases in active coping. These findings suggest temperament, or dispositional aspects of reactivity and regulation, relates to concurrent appraisal and coping processes and additionally predicts change in these processes. Significant indirect effects indicated that appraisal and coping mediated the effects of temperament on adjustment. Threat appraisal mediated the effects of fear and effortful control on internalizing and externalizing problems, and avoidant coping mediated the effect of impulsivity on internalizing problems. These mediated effects suggest that one pathway through which temperament influences adjustment is pre-adolescents’ appraisal and coping. Findings highlight temperament, appraisal and coping as emotion regulation processes relevant to children’s adjustment in response to stress. PMID:25821237
Dementia, Caregiving, and Controlling Frustration
... for you. Behaviors often associated with dementia, like wandering or asking questions repeatedly, can be frustrating for ... or tasks you need help with. Keep in mind that people feel useful and gratified when they ...
Using enquiry in learning: from vision to reality in higher education.
Horne, Maria; Woodhead, Kath; Morgan, Liz; Smithies, Lynda; Megson, Denise; Lyte, Geraldine
2007-02-01
This paper reports on the contribution of six nurse educators to embed enquiry-led learning in a pre-registration nursing programme. Their focus was to evaluate student and facilitator perspectives of a hybrid model of problem-based learning, a form of enquiry-based learning and to focus on facilitators' perceptions of its longer-term utility with large student groups. Problem-based learning is an established learning strategy in healthcare internationally; however, insufficient evidence of its effectiveness with large groups of pre-registration students exists. Fourth Generation Evaluation was used, applying the Nominal Group Technique and Focus Group interviews, for data collection. In total, four groups representing different branches of pre-registration students (n = 121) and 15 facilitators participated. Students identified seven strengths and six areas for development related to problem-based learning. Equally, analysis of facilitators' discussions revealed several themes related to strengths and challenges. The consensus was that using enquiry aided the development of independent learning and encouraged deeper exploration of nursing and allied subject material. However, problems and frustrations were identified in relation to large numbers of groups, group dynamics, room and library resources and personal development. The implications of these findings for longer-term utility with large student groups are discussed.
Simeonova, Diana I; Attalla, Ashraf M; Nguyen, Theresa; Stagnaro, Emily; Knight, Bettina T; Craighead, W Edward; Stowe, Zachary N; Newport, D Jeffrey
2014-12-01
There are no published studies examining concurrent associations between temperament and behavior during toddlerhood in offspring of parents with bipolar disorder (OBD), a population at high familial risk for psychopathology. Better understanding of early determinants contributing to well-being or mental illness in this high-risk population has the potential to aid in the identification of problem domains to be targeted clinically, and facilitate the development of early intervention and prevention initiatives for an appropriate subgroup of children at the youngest possible age. A total of 30 offspring of mothers with BD (mean age=25.4±4.9 months) participated in this study at Emory University. The mothers completed the Early Childhood Behavior Questionnaire (ECBQ) and the Child Behavior Checklist (CBCL). The results of the correlational analyses indicated that the broad temperament dimension Negative Affectivity and the individual ECBQ scales Sadness and Shyness were positively associated with the broad CBCL dimension Internalizing Problems, whereas Sociability was negatively associated with Internalizing Problems. In addition, the temperament scales Soothability and Frustration were negatively and positively associated with Internalizing Problems, respectively. All ECBQ scales included in the broad temperament dimension Effortful Control, except for Cuddliness, were significantly negatively associated with the broad CBCL dimension Externalizing Problems. A significant sex difference was found for the ECBQ scale Positive Anticipation and the CBCL scale Sleep Problems, with a higher mean rank score for girls than for boys. This is the first systematic investigation of temperament and behavior and concurrent associations between these two domains in toddlers of mothers with BD. The present findings provide a platform for future investigations of the contribution of temperament and early behavior to potential well-being or mental illness in OBD.
Passerotti, Carlo C; Franco, Felipe; Bissoli, Julio C C; Tiseo, Bruno; Oliveira, Caio M; Buchalla, Carlos A O; Inoue, Gustavo N C; Sencan, Arzu; Sencan, Aydin; do Pardo, Rogerio Ruscitto; Nguyen, Hiep T
2015-07-01
Robotic assistance may provide for distinct technical advantages over conventional laparoscopic technique. The goals of this study were (1) to objectively evaluate the difference in the learning curves by novice and expert surgeons in performing fundamental laparoscopic skills using conventional laparoscopic surgery (CLS) and robotic-assisted laparoscopic surgery (RALS) and (2) to evaluate the surgeons' frustration level in performing these tasks. Twelve experienced and 31 novices in laparoscopy were prospectively evaluated in performing three standardized laparoscopic tasks in five consecutive, weekly training sessions. Analysis of the learning curves was based on the magnitude, rate, and quickness in performance improvement. The participant's frustration and mood were also evaluated during and after every session. For the novice participants, RALS allowed for shorter time to task completion and greater accuracy. However, significant and rapid improvement in performance as measured by magnitude, rate, and quickness at each session was also seen with CLS. For the experienced surgeons, RALS only provided a slight improvement in performance. For all participants, the use of RALS was associated with less number of sessions in which they felt frustrated, less number of frustration episodes during a session, lower frustration score during and after the session, and higher good mood score. The advantages of RALS may be of most benefit when doing more complex tasks and by less experienced surgeons. RALS should not be used as a replacement for CLS but rather in specific situations in which it has the greatest advantages.
NASA Astrophysics Data System (ADS)
Nisoli, Cristiano; Mahault, Benoit; Saxena, Avadh
We introduce a minimal agent-based model to qualitatively conceptualize the allocation of limited wealth among more abundant opportunities. There the interplay of power, satisfaction and frustration determines the distribution, concentration, and inequality of wealth. Our framework allows us to compare subjective measures of frustration and satisfaction to collective measures of fairness in wealth distribution, such as the Lorenz curve and the Gini index. We find that a completely libertarian, law-of-the-jungle setting, where every agent can acquire wealth from, or lose wealth to, anybody else invariably leads to large inequality. The picture is however dramatically modified when hard constraints are imposed over agents, and they are limited to share wealth with neighbors on a network. We address dynamical societies via an out of equilibrium coevolution of the network, driven by a competition between power and frustration. The ratio between power and frustration controls different dynamical regimes separated by kinetic transitions and characterized by drastically different values of the indices of equality. In particular, it leads to the emergence of three self-organized social classes, lower, middle, and upper class, whose interactions drive a cyclical regime.
Children's negative emotions and ego-resiliency: longitudinal relations with social competence.
Taylor, Zoe E; Eisenberg, Nancy; VanSchyndel, Sarah K; Eggum-Wilkens, Natalie D; Spinrad, Tracy L
2014-04-01
We examined the relations of negative emotions in toddlerhood to the development of ego-resiliency and social competence across early childhood. Specifically, we addressed whether fear and anger/frustration in 30-month-old children (N = 213) was associated with the development of ego-resiliency across 4 time points (42 to 84 months), and, in turn, whether ego-resiliency predicted social competence at 84 months. Child anger/frustration negatively predicted the intercept of ego-resiliency at 42 months (controlling for prior ego-resiliency at 18 months) as well as the slope. Fear did not significantly predict either the intercept or slope of ego-resiliency in the structural model, although it was positively correlated with anger/frustration and was negatively related to ego-resiliency in zero-order correlations. The slope of ego-resiliency was positively related to children's social competence at 84 months; however, the intercept of ego-resiliency (set at 42 months) was not a significant predictor of later social competence. Furthermore, the slope of ego-resiliency mediated the relations between anger/frustration and children's later social competence. The results suggest that individual differences in anger/frustration might contribute to the development of ego-resiliency, which, in turn, is associated with children's social competence.
Consequences of localized frustration for the folding mechanism of the IM7 protein
Sutto, Ludovico; Lätzer, Joachim; Hegler, Joseph A.; Ferreiro, Diego U.; Wolynes, Peter G.
2007-01-01
In the laboratory, IM7 has been found to have an unusual folding mechanism in which an “on-pathway” intermediate with nonnative interactions is formed. We show that this intermediate is a consequence of an unusual cluster of highly frustrated interactions in the native structure. This cluster is involved in the binding of IM7 to its target, Colicin E7. Redesign of residues in this cluster to eliminate frustration is predicted by simulations to lead to faster folding without the population of an intermediate ensemble. PMID:18077415
90 Seconds of Discovery: Frustrated Lewis Pairs
Kathmann, Shawn; Schenter, Greg; Autrey, Tom
2018-01-16
Hydrogen activating catalysts play an important role in producing valuable chemicals, such as biofuels and ammonia. As a part of efforts to develop the next generation of these catalysts, PNNL researchers have found potential in Frustrated Lewis Pairs.
NASA Astrophysics Data System (ADS)
Farkašovský, Pavol
2018-05-01
The small-cluster exact-diagonalization calculations and the projector quantum Monte Carlo method are used to examine the competing effects of geometrical frustration and interaction on ferromagnetism in the Hubbard model on the generalised Shastry-Sutherland lattice. It is shown that the geometrical frustration stabilizes the ferromagnetic state at high electron concentrations ( n ≳ 7/4), where strong correlations between ferromagnetism and the shape of the noninteracting density of states are observed. In particular, it is found that ferromagnetism is stabilized for these values of frustration parameters, which lead to the single-peaked noninterating density of states at the band edge. Once, two or more peaks appear in the noninteracting density of states at the band edge the ferromagnetic state is suppressed. This opens a new route towards the understanding of ferromagnetism in strongly correlated systems.
Engineering of frustration in colloidal artificial ices realized on microfeatured grooved lattices
Ortiz-Ambriz, Antonio; Tierno, Pietro
2016-01-01
Artificial spin ice systems, namely lattices of interacting single domain ferromagnetic islands, have been used to date as microscopic models of frustration induced by lattice topology, allowing for the direct visualization of spin arrangements and textures. However, the engineering of frustrated ice states in which individual spins can be manipulated in situ and the real-time observation of their collective dynamics remain both challenging tasks. Inspired by recent theoretical advances, here we realize a colloidal version of an artificial spin ice system using interacting polarizable particles confined to lattices of bistable gravitational traps. We show quantitatively that ice-selection rules emerge in this frustrated soft matter system by tuning the strength of the pair interactions between the microscopic units. Via independent control of particle positioning and dipolar coupling, we introduce monopole-like defects and strings and use loops with defined chirality as an elementary unit to store binary information. PMID:26830629
Engineering of frustration in colloidal artificial ices realized on microfeatured grooved lattices.
Ortiz-Ambriz, Antonio; Tierno, Pietro
2016-02-01
Artificial spin ice systems, namely lattices of interacting single domain ferromagnetic islands, have been used to date as microscopic models of frustration induced by lattice topology, allowing for the direct visualization of spin arrangements and textures. However, the engineering of frustrated ice states in which individual spins can be manipulated in situ and the real-time observation of their collective dynamics remain both challenging tasks. Inspired by recent theoretical advances, here we realize a colloidal version of an artificial spin ice system using interacting polarizable particles confined to lattices of bistable gravitational traps. We show quantitatively that ice-selection rules emerge in this frustrated soft matter system by tuning the strength of the pair interactions between the microscopic units. Via independent control of particle positioning and dipolar coupling, we introduce monopole-like defects and strings and use loops with defined chirality as an elementary unit to store binary information.
Engineering of frustration in colloidal artificial ices realized on microfeatured grooved lattices
NASA Astrophysics Data System (ADS)
Tierno, Pietro
Artificial spin-ice systems, namely lattices of interacting single domain ferromagnetic islands, have been used to date as microscopic models of frustration induced by lattice topology, allowing for the direct visualization of spin arrangements and textures. However, the engineering of frustrated ice states in which individual spins can be manipulated in situ and the real-time observation of their collective dynamics remain both challenging tasks. Inspired by recent theoretical advances, we realize a colloidal version of an artificial spin ice system using interacting polarizable particles confined to lattices of bistable gravitational traps. We show quantitatively that ice-selection rules emerge in this frustrated soft matter system by tuning the strength of the pair-interactions between the microscopic units. Via independent control of particle positioning and dipolar coupling, we introduce monopole-like defects and strings and use loops with defined chirality as an elementary unit to store binary information.
Engineering of frustration in colloidal artificial ices realized on microfeatured grooved lattices
NASA Astrophysics Data System (ADS)
Ortiz-Ambriz, Antonio; Tierno, Pietro
2016-02-01
Artificial spin ice systems, namely lattices of interacting single domain ferromagnetic islands, have been used to date as microscopic models of frustration induced by lattice topology, allowing for the direct visualization of spin arrangements and textures. However, the engineering of frustrated ice states in which individual spins can be manipulated in situ and the real-time observation of their collective dynamics remain both challenging tasks. Inspired by recent theoretical advances, here we realize a colloidal version of an artificial spin ice system using interacting polarizable particles confined to lattices of bistable gravitational traps. We show quantitatively that ice-selection rules emerge in this frustrated soft matter system by tuning the strength of the pair interactions between the microscopic units. Via independent control of particle positioning and dipolar coupling, we introduce monopole-like defects and strings and use loops with defined chirality as an elementary unit to store binary information.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, H.; Jang, H.; Kang, B. Y.
The frustrated magnet has been regarded as a system that could be a promising host material for the quantum spin liquid (QSL). However, it is difficult to determine the spin configuration and the corresponding mechanism in this system, because of its geometrical frustration ( i.e., crystal structure and symmetry). Herein, we systematically investigate one of the geometrically frustrated magnets, the TbB 4 compound. Using resonant soft x-ray scattering (RSXS), we explored its spin configuration, as well as Tb's quadrupole. Comprehensive evaluations of the temperature and photon energy/polarization dependences of the RSXS signals reveal the mechanism of spin reorientation upon coolingmore » down, which is the sophisticated interplay between the Tb spin and the crystal symmetry rather than its orbit (quadrupole). Here, our results and their implications would further shed a light on the search for possible realization of QSL.« less
Visualizing and Steering Dissociative Frustrated Double Ionization of Hydrogen Molecules
NASA Astrophysics Data System (ADS)
Zhang, Wenbin; Yu, Zuqing; Gong, Xiaochun; Wang, Junping; Lu, Peifen; Li, Hui; Song, Qiying; Ji, Qinying; Lin, Kang; Ma, Junyang; Li, Hanxiao; Sun, Fenghao; Qiang, Junjie; Zeng, Heping; He, Feng; Wu, Jian
2017-12-01
We experimentally visualize the dissociative frustrated double ionization of hydrogen molecules by using few-cycle laser pulses in a pump-probe scheme, in which process the tunneling ionized electron is recaptured by one of the outgoing nuclei of the breaking molecule. Three internuclear distances are recognized to enhance the dissociative frustrated double ionization of molecules at different instants after the first ionization step. The recapture of the electron can be further steered to one of the outgoing nuclei as desired by using phase-controlled two-color laser pulses. Both the experimental measurements and numerical simulations suggest that the Rydberg atom is favored to emit to the direction of the maximum of the asymmetric optical field. Our results on the one hand intuitively visualize the dissociative frustrated double ionization of molecules, and on the other hand open the possibility to selectively excite the heavy fragment ejected from a molecule.
Mastery-style homework exercises in introductory physics courses: Implementation matters
NASA Astrophysics Data System (ADS)
Gutmann, Brianne; Gladding, Gary; Lundsgaard, Morten; Stelzer, Timothy
2018-06-01
Encouraged by positive clinical results at the University of Illinois, mastery-style homework was integrated into a large semester-long preparatory physics course via an online homework system that used narrated animated video solutions as correctives. This paper discusses the impact and evolution of the homework in its first two years. The first iteration revealed that students were frustrated and did not engage with the system in an effective way. Intending to reduce that frustration and quell negative behavior, the mastery requirement was relaxed, transfer between versions was reduced, and the addition of a direct discussion with students about the homework were implemented in its second year. The results showed that details of implementation can substantially affect students' behavior; large and statistically significant effects were observed as a reduction in frustration (with self-identified "frustrated" students dropping from 60% in 2014 to 30% in 2015) and improvement in performance (average student mastery rate of 59% to 69%).
Kondo destruction in a quantum paramagnet with magnetic frustration
NASA Astrophysics Data System (ADS)
Zhang, Jiahao; Zhao, Hengcan; Lv, Meng; Hu, Sile; Isikawa, Yosikazu; Yang, Yi-feng; Si, Qimiao; Steglich, Frank; Sun, Peijie
2018-06-01
We report results of isothermal magnetotransport and susceptibility measurements at elevated magnetic fields B down to very low temperatures T on single crystals of the frustrated Kondo-lattice system CePdAl. They reveal a B*(T ) line within the paramagnetic part of the phase diagram. This line denotes a thermally broadened "small"-to-"large" Fermi-surface crossover which substantially narrows upon cooling. At B0 *=B*(T =0 ) =(4.6 ±0.1 ) T , this B*(T ) line merges with two other crossover lines, viz. Tp(B ) below and TFL(B ) above B0 *. Tp characterizes a frustration-dominated spin-liquid state, while TFL is the Fermi-liquid temperature associated with the lattice Kondo effect. Non-Fermi-liquid phenomena which are commonly observed near a "Kondo-destruction" quantum-critical point cannot be resolved in CePdAl. Our observations reveal a rare case where Kondo coupling, frustration, and quantum criticality are closely intertwined.
Huang, H.; Jang, H.; Kang, B. Y.; ...
2018-05-05
The frustrated magnet has been regarded as a system that could be a promising host material for the quantum spin liquid (QSL). However, it is difficult to determine the spin configuration and the corresponding mechanism in this system, because of its geometrical frustration ( i.e., crystal structure and symmetry). Herein, we systematically investigate one of the geometrically frustrated magnets, the TbB 4 compound. Using resonant soft x-ray scattering (RSXS), we explored its spin configuration, as well as Tb's quadrupole. Comprehensive evaluations of the temperature and photon energy/polarization dependences of the RSXS signals reveal the mechanism of spin reorientation upon coolingmore » down, which is the sophisticated interplay between the Tb spin and the crystal symmetry rather than its orbit (quadrupole). Here, our results and their implications would further shed a light on the search for possible realization of QSL.« less
NASA Astrophysics Data System (ADS)
Heim, N. A.; Saltzman, J.; Payne, J.
2014-12-01
The chasm between classroom science and scientific research is bridged in the History of Life Internships at Stanford University. The primary foci of the internships are collection of new scientific data and original scientific research. While traditional high school science courses focus on learning content and laboratory skills, students are rarely engaged in real scientific research. Even in experiential learning environments, students investigate phenomena with known outcomes under idealized conditions. In the History of Life Internships, high school youth worked full time during the summers of 2013 and 2014 to collect body size data on fossil Echinoderms and Ostracods, measuring more than 20,000 species in total. These data are contributed to the larger research efforts in the Stanford Paleobiology Lab, but they also serve as a source of data for interns to conduct their own scientific research. Over the course of eight weeks, interns learn about previous research on body size evolution, collect data, develop their own hypotheses, test their hypotheses, and communicate their results to their peers and the larger scientific community: the 2014 interns have submitted eight abstracts to this meeting for the youth session entitled Bright STaRS where they will present their research findings. Based on a post-internship survey, students in the 2013 History of Life cohort had more positive attitudes towards science and had a better understanding of how to conduct scientific research compared to interns in the Earth Sciences General Internship Program, where interns typically do not complete their own research project from start to finish. In 2014, we implemented both pre- and post-internship surveys to determine if these positive attitudes were developed over the course of the internship. Conducting novel research inspires both the students and instructors. Scientific data collection often involves many hours of repetitive work, but answering big questions typically requires big datasets. Our team of 20 used calipers and data-rich compendia of fossil species to collect copious amounts of data. Our interns experienced the joys, frustrations, tedium and excitement of being scientists and discovering something new about the natural world for the first time.
Modulation of frustration in folding by sequence permutation.
Nobrega, R Paul; Arora, Karunesh; Kathuria, Sagar V; Graceffa, Rita; Barrea, Raul A; Guo, Liang; Chakravarthy, Srinivas; Bilsel, Osman; Irving, Thomas C; Brooks, Charles L; Matthews, C Robert
2014-07-22
Folding of globular proteins can be envisioned as the contraction of a random coil unfolded state toward the native state on an energy surface rough with local minima trapping frustrated species. These substructures impede productive folding and can serve as nucleation sites for aggregation reactions. However, little is known about the relationship between frustration and its underlying sequence determinants. Chemotaxis response regulator Y (CheY), a 129-amino acid bacterial protein, has been shown previously to populate an off-pathway kinetic trap in the microsecond time range. The frustration has been ascribed to premature docking of the N- and C-terminal subdomains or, alternatively, to the formation of an unproductive local-in-sequence cluster of branched aliphatic side chains, isoleucine, leucine, and valine (ILV). The roles of the subdomains and ILV clusters in frustration were tested by altering the sequence connectivity using circular permutations. Surprisingly, the stability and buried surface area of the intermediate could be increased or decreased depending on the location of the termini. Comparison with the results of small-angle X-ray-scattering experiments and simulations points to the accelerated formation of a more compact, on-pathway species for the more stable intermediate. The effect of chain connectivity in modulating the structures and stabilities of the early kinetic traps in CheY is better understood in terms of the ILV cluster model. However, the subdomain model captures the requirement for an intact N-terminal domain to access the native conformation. Chain entropy and aliphatic-rich sequences play crucial roles in biasing the early events leading to frustration in the folding of CheY.
Frandsen, Benjamin A.; Billinge, Simon J. L.; Ross, Kathryn A.; ...
2017-12-29
Here, we present time-of-flight neutron total scattering and polarized neutron scattering measurements of the magnetically frustrated compounds NaCaCo 2F 7 and NaSrCo 2F 7, which belong to a class of recently discovered pyrochlore compounds based on transition metals and fluorine. The magnetic pair distribution function (mPDF) technique is used to analyze and model the total scattering data in real space. We find that a previously-proposed model of short-range XY-like correlations with a length scale of 10-15 Å, combined with nearest-neighbor collinear antiferromagnetic correlations, accurately describes the mPDF data at low temperature, confirming the magnetic ground state in these materials. Thismore » model is further verified by the polarized neutron scattering data. From an analysis of the temperature dependence of the mPDF and polarized neutron scattering data, we find that short-range correlations persist on the nearest-neighbor length scale up to 200 K, approximately two orders of magnitude higher than the spin freezing temperatures of these compounds. These results highlight the opportunity presented by these new pyrochlore compounds to study the effects of geometric frustration at relatively high temperatures, while also advancing the mPDF technique and providing a novel opportunity to investigate a genuinely short-range-ordered magnetic ground state directly in real space.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frandsen, Benjamin A.; Billinge, Simon J. L.; Ross, Kathryn A.
Here, we present time-of-flight neutron total scattering and polarized neutron scattering measurements of the magnetically frustrated compounds NaCaCo 2F 7 and NaSrCo 2F 7, which belong to a class of recently discovered pyrochlore compounds based on transition metals and fluorine. The magnetic pair distribution function (mPDF) technique is used to analyze and model the total scattering data in real space. We find that a previously-proposed model of short-range XY-like correlations with a length scale of 10-15 Å, combined with nearest-neighbor collinear antiferromagnetic correlations, accurately describes the mPDF data at low temperature, confirming the magnetic ground state in these materials. Thismore » model is further verified by the polarized neutron scattering data. From an analysis of the temperature dependence of the mPDF and polarized neutron scattering data, we find that short-range correlations persist on the nearest-neighbor length scale up to 200 K, approximately two orders of magnitude higher than the spin freezing temperatures of these compounds. These results highlight the opportunity presented by these new pyrochlore compounds to study the effects of geometric frustration at relatively high temperatures, while also advancing the mPDF technique and providing a novel opportunity to investigate a genuinely short-range-ordered magnetic ground state directly in real space.« less
NASA Astrophysics Data System (ADS)
Frandsen, Benjamin A.; Ross, Kate A.; Krizan, Jason W.; Nilsen, Gøran J.; Wildes, Andrew R.; Cava, Robert J.; Birgeneau, Robert J.; Billinge, Simon J. L.
2017-12-01
We present time-of-flight neutron total scattering and polarized neutron scattering measurements of the magnetically frustrated compounds NaCaCo2F7 and NaSrCo2F7 , which belong to a class of recently discovered pyrochlore compounds based on transition metals and fluorine. The magnetic pair distribution function (mPDF) technique is used to analyze and model the total scattering data in real space. We find that a previously proposed model of short-range XY-like correlations with a length scale of 10-15 Å, combined with nearest-neighbor collinear antiferromagnetic correlations, accurately describes the mPDF data at low temperature, confirming the magnetic ground state in these materials. This model is further verified by the polarized neutron scattering data. From an analysis of the temperature dependence of the mPDF and polarized neutron scattering data, we find that short-range correlations persist on the nearest-neighbor length scale up to 200 K, approximately two orders of magnitude higher than the spin freezing temperatures of these compounds. These results highlight the opportunity presented by these new pyrochlore compounds to study the effects of geometric frustration at relatively high temperatures, while also advancing the mPDF technique and providing an opportunity to investigate a genuinely short-range-ordered magnetic ground state directly in real space.
Bubble and skyrmion crystals in frustrated magnets with easy-axis anisotropy
Hayami, Satoru; Lin, Shi-Zeng; Batista, Cristian D.
2016-05-12
We clarify the conditions for the emergence of multiple-Q structures out of lattice and easy-axis spin anisotropy in frustrated magnets. By considering magnets whose exchange interaction has multiple global minima in momentum space, we find that both types of anisotropy stabilize triple-Q orderings. Moderate anisotropy leads to a magnetic field-induced skyrmion crystal, which evolves into a bubble crystal for increasing spatial and spin anisotropy. Finally, the bubble crystal exhibits a quasi-continuous (devil’s staircase) temperature dependent ordering wave-vector, characteristic of the competition between frustrated exchange and strong easy-axis anisotropy.
Tuning the fragility of a glass-forming liquid by curving space.
Sausset, François; Tarjus, Gilles; Viot, Pascal
2008-10-10
We investigate the influence of space curvature, and of the associated frustration, on the dynamics of a model glass former: a monatomic liquid on the hyperbolic plane. We find that the system's fragility, i.e., the sensitivity of the relaxation time to temperature changes, increases as one decreases the frustration. As a result, curving space provides a way to tune fragility and make it as large as wanted. We also show that the nature of the emerging "dynamic heterogeneities", another distinctive feature of slowly relaxing systems, is directly connected to the presence of frustration-induced topological defects.
NASA Astrophysics Data System (ADS)
Zheng, Zhen-Yu; Li, Peng
2018-04-01
We consider the time evolution of two-point correlation function in the transverse-field Ising chain (TFIC) with ring frustration. The time-evolution procedure we investigated is equivalent to a quench process in which the system is initially prepared in a classical kink state and evolves according to the time-dependent Schrödinger equation. Within a framework of perturbative theory (PT) in the strong kink phase, the evolution of the correlation function is disclosed to demonstrate a qualitatively new behavior in contrast to the traditional case without ring frustration.
Rodenburg, T B; Koene, P; Spruijt, B M
2004-02-27
The effect of rearing conditions on feather pecking and reaction to frustration was studied in two lines of laying hens. From commercial rearing conditions (large group, no mother hen), seven birds from a high feather pecking line (HC birds) and eight birds from a low feather pecking line (LC birds) were used. From semi-natural rearing conditions (small group, mother hen present) seven birds from the high feather pecking line (HN birds) were used. Feather pecking behaviour of HC, LC, and HN groups was recorded for 30 min. After that, each bird was food deprived and trained to peck a key for a food reward in a Skinnerbox. After training, each bird was subjected to a frustration session in a Skinnerbox, where the feeder was covered with Perspex. Three HC birds showed severe feather pecking, compared with one HN bird and zero LC birds. Differences in reaction to frustration were found between birds from different lines, but not in birds from different rearing conditions. LC birds tended to put their head in the feeder more frequently than HC birds over all sessions. Although limited, this study indicates that rearing conditions influence feather pecking, but not reaction to frustration.
Children’s Negative Emotions and Ego-Resiliency: Longitudinal Relations With Social Competence
Taylor, Zoe E.; Eisenberg, Nancy; VanSchyndel, Sarah K.; Eggum-Wilkens, Natalie D.; Spinrad, Tracy L.
2015-01-01
We examined the relations of negative emotions in toddlerhood to the development of ego-resiliency and social competence across early childhood. Specifically, we addressed whether fear and anger/frustration in 30-month-old children (N = 213) was associated with the development of ego-resiliency across 4 time points (42 to 84 months), and, in turn, whether ego-resiliency predicted social competence at 84 months. Child anger/frustration negatively predicted the intercept of ego-resiliency at 42 months (controlling for prior ego-resiliency at 18 months) as well as the slope. Fear did not significantly predict either the intercept or slope of ego-resiliency in the structural model, although it was positively correlated with anger/frustration and was negatively related to ego-resiliency in zero-order correlations. The slope of ego-resiliency was positively related to children’s social competence at 84 months; however, the intercept of ego-resiliency (set at 42 months) was not a significant predictor of later social competence. Furthermore, the slope of ego-resiliency mediated the relations between anger/frustration and children’s later social competence. The results suggest that individual differences in anger/frustration might contribute to the development of ego-resiliency, which, in turn, is associated with children’s social competence. PMID:24364850
Nanoparticle hardness controls the internalization pathway for drug delivery
NASA Astrophysics Data System (ADS)
Li, Ye; Zhang, Xianren; Cao, Dapeng
2015-01-01
Nanoparticle (NP)-based drug delivery systems offer fundamental advantages over current therapeutic agents that commonly display a longer circulation time, lower toxicity, specific targeted release, and greater bioavailability. For successful NP-based drug delivery it is essential that the drug-carrying nanocarriers can be internalized by the target cells and transported to specific sites, and the inefficient internalization of nanocarriers is often one of the major sources for drug resistance. In this work, we use the dissipative particle dynamics simulation to investigate the effect of NP hardness on their internalization efficiency. Three simplified models of NP platforms for drug delivery, including polymeric NP, liposome and solid NP, are designed here to represent increasing nanocarrier hardness. Simulation results indicate that NP hardness controls the internalization pathway for drug delivery. Rigid NPs can enter the cell by a pathway of endocytosis, whereas for soft NPs the endocytosis process can be inhibited or frustrated due to wrapping-induced shape deformation and non-uniform ligand distribution. Instead, soft NPs tend to find one of three penetration pathways to enter the cell membrane via rearranging their hydrophobic and hydrophilic segments. Finally, we show that the interaction between nanocarriers and drug molecules is also essential for effective drug delivery.
Frustration-Instigated Behavior and Learned Helplessness.
ERIC Educational Resources Information Center
Winefield, Anthony H.
1979-01-01
Compares M. E. P. Seligman's recent work on learned helplessness with N. R. F. Maier's 30-year-old work on frustration behavior. Notes striking similarities between the two approaches. Concludes that the learned helplessness model might explain the "abnormal fixations" that Maier reported. (Author/RL)
Perceptions of Beginning Public School Principals.
ERIC Educational Resources Information Center
Lyons, James E.
1993-01-01
Summarizes a study to determine principal's perceptions of their competency in primary responsibility areas and their greatest challenges and frustrations. Beginning principals are challenged by delegating responsibilities and becoming familiar with the principal's role, the local school, and school operations. Their major frustrations are role…
The effect of multimodal and enriched feedback on SMR-BCI performance.
Sollfrank, T; Ramsay, A; Perdikis, S; Williamson, J; Murray-Smith, R; Leeb, R; Millán, J D R; Kübler, A
2016-01-01
This study investigated the effect of multimodal (visual and auditory) continuous feedback with information about the uncertainty of the input signal on motor imagery based BCI performance. A liquid floating through a visualization of a funnel (funnel feedback) provided enriched visual or enriched multimodal feedback. In a between subject design 30 healthy SMR-BCI naive participants were provided with either conventional bar feedback (CB), or visual funnel feedback (UF), or multimodal (visual and auditory) funnel feedback (MF). Subjects were required to imagine left and right hand movement and were trained to control the SMR based BCI for five sessions on separate days. Feedback accuracy varied largely between participants. The MF feedback lead to a significantly better performance in session 1 as compared to the CB feedback and could significantly enhance motivation and minimize frustration in BCI use across the five training sessions. The present study demonstrates that the BCI funnel feedback allows participants to modulate sensorimotor EEG rhythms. Participants were able to control the BCI with the funnel feedback with better performance during the initial session and less frustration compared to the CB feedback. The multimodal funnel feedback provides an alternative to the conventional cursorbar feedback for training subjects to modulate their sensorimotor rhythms. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
ERIC Educational Resources Information Center
Owen, Trevor
1996-01-01
Discusses teaching English in Toronto, Ontario, Canada, where the majority of students have acquired English as an additional language. Suggests that teaching English in these classes presents rewarding and frustrating challenges--challenges which are at least as rewarding and frustrating for students as they are for teachers. Describes the ESL…
NASA Astrophysics Data System (ADS)
Killi, Matthew; Trotzky, Stefan; Paramekanti, Arun
2012-12-01
Bosons and fermions, in the presence of frustration or background gauge fields, can form many-body ground states that support equilibrium charge or spin currents. Motivated by the experimental creation of frustration or synthetic gauge fields in ultracold atomic systems, we propose a general scheme by which making a sudden anisotropic quench of the atom tunneling across the lattice and tracking the ensuing density modulations provides a powerful and gauge-invariant route to probing diverse equilibrium current patterns. Using illustrative examples of trapped superfluid Bose and normal Fermi systems in the presence of artificial magnetic fluxes on square lattices, and frustrated bosons in a triangular lattice, we show that this scheme to probe equilibrium bulk current order works independent of particle statistics. We also show that such quenches can detect chiral edge modes in gapped topological states, such as quantum Hall or quantum spin Hall insulators.
Magnon Hall effect without Dzyaloshinskii-Moriya interaction.
Owerre, S A
2017-01-25
Topological magnon bands and magnon Hall effect in insulating collinear ferromagnets are induced by the Dzyaloshinskii-Moriya interaction (DMI) even at zero magnetic field. In the geometrically frustrated star lattice, a coplanar/noncollinear [Formula: see text] magnetic ordering may be present due to spin frustration. This magnetic structure, however, does not exhibit topological magnon effects even with DMI in contrast to collinear ferromagnets. We show that a magnetic field applied perpendicular to the star plane induces a non-coplanar spin configuration with nonzero spin scalar chirality, which provides topological effects without the need of DMI. The non-coplanar spin texture originates from the topology of the spin configurations and does not need the presence of DMI or magnetic ordering, which suggests that this phenomenon may be present in the chiral spin liquid phases of frustrated magnetic systems. We propose that these anomalous topological magnon effects can be accessible in polymeric iron (III) acetate-a star-lattice antiferromagnet with both spin frustration and long-range magnetic ordering.
Emergent Chiral Spin State in the Mott Phase of a Bosonic Kane-Mele-Hubbard Model
NASA Astrophysics Data System (ADS)
Plekhanov, Kirill; Vasić, Ivana; Petrescu, Alexandru; Nirwan, Rajbir; Roux, Guillaume; Hofstetter, Walter; Le Hur, Karyn
2018-04-01
Recently, the frustrated X Y model for spins 1 /2 on the honeycomb lattice has attracted a lot of attention in relation with the possibility to realize a chiral spin liquid state. This model is relevant to the physics of some quantum magnets. Using the flexibility of ultracold atom setups, we propose an alternative way to realize this model through the Mott regime of the bosonic Kane-Mele-Hubbard model. The phase diagram of this model is derived using bosonic dynamical mean-field theory. Focusing on the Mott phase, we investigate its magnetic properties as a function of frustration. We do find an emergent chiral spin state in the intermediate frustration regime. Using exact diagonalization we study more closely the physics of the effective frustrated X Y model and the properties of the chiral spin state. This gapped phase displays a chiral order, breaking time-reversal and parity symmetry, but is not topologically ordered (the Chern number is zero).
Oliver, Michele L.; Nigg, Joel T.; Cassavaugh, Nicholas D.; Backs, Richard W.
2015-01-01
Objective The present study examined the role of negative emotions on driving performance in relation to ADHD, by comparing young adults scoring high on measures of ADHD (n = 20) with a control group (n = 22). Method The authors used cardiorespiratory physiological measures, simulated driving behavior, and self-report to examine how participants with high and low ADHD symptoms responded to frustration and to determine how frustration affected simulated driving performance. Results Groups did not differ in operational driving skills, but participants with high ADHD symptoms reported more frustration and exhibited more impairment at the tactical level of driving performance than the controls. There was significant suppression of respiratory sinus arrhythmia from resting baseline during tasks, but it did not differ between groups during driving. Conclusion This article proposes that remedial driver training for ADHD populations should focus more on the control of negative emotions rather than on attention or fundamental driving skills. PMID:21490175
Parthasarathy, S; Jaiganesh, K; Duraisamy
2014-01-01
The implementation of yogic practices has proven benefits in both organic and psychological diseases. Forty-five women with anxiety selected by a random sampling method were divided into three groups. Experimental group I was subjected to asanas, relaxation and pranayama while Experimental group II was subjected to an integrated yoga module. The control group did not receive any intervention. Anxiety was measured by Taylor's Manifest Anxiety Scale before and after treatment. Frustration was measured through Reaction to Frustration Scale. All data were spread in an Excel sheet to be analysed with SPSS 16 software using analysis of covariance (ANCOVA). Selected yoga and asanas decreased anxiety and frustration scores but treatment with an integrated yoga module resulted in significant reduction of anxiety and frustration. To conclude, the practice of asanas and yoga decreased anxiety in women, and yoga as an integrated module significantly improved anxiety scores in young women with proven anxiety without any ill effects.
Tokiwa, Y.; Yamashita, T.; Udagawa, M.; Kittaka, S.; Sakakibara, T; Terazawa, D.; Shimoyama, Y.; Terashima, T.; Yasui, Y.; Shibauchi, T.; Matsuda, Y.
2016-01-01
The low-energy elementary excitations in frustrated quantum magnets have fascinated researchers for decades. In frustrated Ising magnets on a pyrochlore lattice possessing macroscopically degenerate spin-ice ground states, the excitations have been discussed in terms of classical magnetic monopoles, which do not contain quantum fluctuations. Here we report unusual behaviours of magneto-thermal conductivity in the disordered spin-liquid regime of pyrochlore Yb2Ti2O7, which hosts frustrated spin-ice correlations with large quantum fluctuations owing to pseudospin-1/2 of Yb ions. The analysis of the temperature and magnetic field dependencies shows the presence of gapped elementary excitations. We find that the gap energy is largely suppressed from that expected in classical monopoles. Moreover, these excitations propagate a long distance without being scattered, in contrast to the diffusive nature of classical monopoles. These results suggests the emergence of highly itinerant quantum magnetic monopole, which is a heavy quasiparticle that propagates coherently in three-dimensional spin liquids. PMID:26912080
Tokiwa, Y; Yamashita, T; Udagawa, M; Kittaka, S; Sakakibara, T; Terazawa, D; Shimoyama, Y; Terashima, T; Yasui, Y; Shibauchi, T; Matsuda, Y
2016-02-25
The low-energy elementary excitations in frustrated quantum magnets have fascinated researchers for decades. In frustrated Ising magnets on a pyrochlore lattice possessing macroscopically degenerate spin-ice ground states, the excitations have been discussed in terms of classical magnetic monopoles, which do not contain quantum fluctuations. Here we report unusual behaviours of magneto-thermal conductivity in the disordered spin-liquid regime of pyrochlore Yb2Ti2O7, which hosts frustrated spin-ice correlations with large quantum fluctuations owing to pseudospin-1/2 of Yb ions. The analysis of the temperature and magnetic field dependencies shows the presence of gapped elementary excitations. We find that the gap energy is largely suppressed from that expected in classical monopoles. Moreover, these excitations propagate a long distance without being scattered, in contrast to the diffusive nature of classical monopoles. These results suggests the emergence of highly itinerant quantum magnetic monopole, which is a heavy quasiparticle that propagates coherently in three-dimensional spin liquids.
Engineering of frustration in colloidal artificial ice (Conference Presentation)
NASA Astrophysics Data System (ADS)
Ortiz-Ambriz, Antonio; Tierno, Pietro
2016-09-01
Artificial spin-ice systems have been used to date as microscopic models of frustration induced by lattice topology, as they allow for the direct visualization of spin arrangements and textures. However, the engineering of frustrated ice states in which individual spins can be manipulated in situ and the real-time observation of their collective dynamics remain both challenging tasks. Recently, an analogue system has been proposed theoretically, where an optical landscape confined colloidal particles that interacted electrostatically. Here we realize experimentally another version of a colloidal artificial ice system using interacting magnetically polarizable particles confined to lattices of bistable gravitational traps. We show quantitatively that ice-selection rules emerge in this frustrated soft matter system by tuning the strength of the pair-interactions between the microscopic units. By using optical tweezers, we can control particle positioning and dipolar coupling, we introduce monopole-like defects and strings and use loops with defined chirality as an elementary unit to store binary information.
Quantum order by disorder in frustrated diamond lattice antiferromagnets.
Bernier, Jean-Sébastien; Lawler, Michael J; Kim, Yong Baek
2008-07-25
We present a quantum theory of frustrated diamond lattice antiferromagnets. Considering quantum fluctuations as the predominant mechanism relieving spin frustration, we find a rich phase diagram comprising of six phases with coplanar spiral ordering in addition to the Néel phase. By computing the specific heat of these ordered phases, we obtain a remarkable agreement between (k, k, 0) spiral ordering and the experimental specific heat data for the diamond lattice spinel compounds MnSc2S4, Co3O4, and CoRh2O4, i.e., specific heat data is a strong evidence for (k, k, 0) spiral ordering in all of these materials. This prediction can be tested in future neutron scattering experiments on Co3O4 and CoRh2O4, and is consistent with existing neutron scattering data on MnSc2S4. Based on this agreement, we infer a monotonically increasing relationship between frustration and the strength of quantum fluctuations.
Frustrated spin chains in strong magnetic field: Dilute two-component Bose gas regime
NASA Astrophysics Data System (ADS)
Kolezhuk, A. K.; Heidrich-Meisner, F.; Greschner, S.; Vekua, T.
2012-02-01
We study the ground state of frustrated spin-S chains in a strong magnetic field in the immediate vicinity of saturation. In strongly frustrated chains, the magnon dispersion has two degenerate minima at inequivalent momenta ±Q, and just below the saturation field the system can be effectively represented as a dilute one-dimensional lattice gas of two species of bosons that correspond to magnons with momenta around ±Q. We present a theory of effective interactions in such a dilute magnon gas that allows us to make quantitative predictions for arbitrary values of the spin. With the help of this method, we are able to establish the magnetic phase diagram of frustrated chains close to saturation and study phase transitions between several nontrivial states, including a two-component Luttinger liquid, a vector chiral phase, and phases with bound magnons. We study those phase transitions numerically and find a good agreement with our analytical predictions.
Kardas, J; Langenmayr, A
1999-04-01
Related to the research of the effects of separation and divorce on children there is a lack of empirical studies in Germany. The following cross-sectional field-study directly investigate 48 children from divorced and 32 children from two-parent-families regarding socio-emotional and some cognitive characteristics (nonclinical samples). Projective and semi-projective tests were the preferred instruments. One of the main questions was related to frustration behavior, measured by the Rosenzweig-Picture-Frustration Test (childrens form). This test was used for the first time by a population of German children of divorce. Children of divorce showed a special frustration behavior, a so called M-profile showing many impunitive reactions. They avoid direct conflicts or struggle and try to deny the frustration. Also the subtests of the Hamburg-Wechsler-Intelligence test for children (HAWIK) show clearly that children from divorced families obtain much poorer test values in contrast to children from two-parent homes.
Das, Payel; Matysiak, Silvina; Clementi, Cecilia
2005-01-01
Coarse-grained models have been extremely valuable in promoting our understanding of protein folding. However, the quantitative accuracy of existing simplified models is strongly hindered either from the complete removal of frustration (as in the widely used Gō-like models) or from the compromise with the minimal frustration principle and/or realistic protein geometry (as in the simple on-lattice models). We present a coarse-grained model that “naturally” incorporates sequence details and energetic frustration into an overall minimally frustrated folding landscape. The model is coupled with an optimization procedure to design the parameters of the protein Hamiltonian to fold into a desired native structure. The application to the study of src-Src homology 3 domain shows that this coarse-grained model contains the main physical-chemical ingredients that are responsible for shaping the folding landscape of this protein. The results illustrate the importance of nonnative interactions and energetic heterogeneity for a quantitative characterization of folding mechanisms. PMID:16006532
Workload Assessment for the Combat Vehicle Command and Control Company- Level Evaluation
1992-04-01
and descriptive statistics are in Appendix F3 . Shell and SITREP Reports. No significant total score workload differences were obtained for these tasks...Cases= 9: missing Cases = 15 OR 16.5 PCT. F2-20 Appendix F3 Prepare/Send CFF Report Variable or term GRP(l) ANOVA factor comparing CVCC with Ml Baseline...subscale score for task CMT4WL5 Effort subscale score for task CMT4WL6 Frustration subscale score for task F3 -1 Deviation Scores: Task 4 - Prepare/Send CFF
Is Geometric Frustration-Induced Disorder a Recipe for High Ionic Conductivity?
Düvel, Andre; Heitjans, Paul; Fedorov, Pavel; Scholz, Gudrun; Cibin, Giannantonio; Chadwick, Alan V; Pickup, David M; Ramos, Silvia; Sayle, Lewis W L; Sayle, Emma K L; Sayle, Thi X T; Sayle, Dean C
2017-04-26
Ionic conductivity is ubiquitous to many industrially important applications such as fuel cells, batteries, sensors, and catalysis. Tunable conductivity in these systems is therefore key to their commercial viability. Here, we show that geometric frustration can be exploited as a vehicle for conductivity tuning. In particular, we imposed geometric frustration upon a prototypical system, CaF 2 , by ball milling it with BaF 2 , to create nanostructured Ba 1-x Ca x F 2 solid solutions and increased its ionic conductivity by over 5 orders of magnitude. By mirroring each experiment with MD simulation, including "simulating synthesis", we reveal that geometric frustration confers, on a system at ambient temperature, structural and dynamical attributes that are typically associated with heating a material above its superionic transition temperature. These include structural disorder, excess volume, pseudovacancy arrays, and collective transport mechanisms; we show that the excess volume correlates with ionic conductivity for the Ba 1-x Ca x F 2 system. We also present evidence that geometric frustration-induced conductivity is a general phenomenon, which may help explain the high ionic conductivity in doped fluorite-structured oxides such as ceria and zirconia, with application for solid oxide fuel cells. A review on geometric frustration [ Nature 2015 , 521 , 303 ] remarks that classical crystallography is inadequate to describe systems with correlated disorder, but that correlated disorder has clear crystallographic signatures. Here, we identify two possible crystallographic signatures of geometric frustration: excess volume and correlated "snake-like" ionic transport; the latter infers correlated disorder. In particular, as one ion in the chain moves, all the other (correlated) ions in the chain move simultaneously. Critically, our simulations reveal snake-like chains, over 40 Å in length, which indicates long-range correlation in our disordered systems. Similarly, collective transport in glassy materials is well documented [for example, J. Chem. Phys. 2013 , 138 , 12A538 ]. Possible crystallographic nomenclatures, to be used to describe long-range order in disordered systems, may include, for example, the shape, length, and branching of the "snake" arrays. Such characterizations may ultimately provide insight and differences between long-range order in disordered, amorphous, or liquid states and processes such as ionic conductivity, melting, and crystallization.
Kassas, Nawal; Tanguy, Emeline; Thahouly, Tamou; Fouillen, Laetitia; Heintz, Dimitri; Chasserot-Golaz, Sylvette; Bader, Marie-France; Grant, Nancy J; Vitale, Nicolas
2017-03-10
Phosphatidic acid (PA) is the simplest phospholipid naturally existing in living organisms, but it constitutes only a minor fraction of total cell lipids. PA has attracted considerable attention because it is a phospholipid precursor, a lipid second messenger, and a modulator of membrane shape, and it has thus been proposed to play key cellular functions. The dynamics of PA in cells and in subcellular compartments, however, remains an open question. The recent generation of fluorescent probes for PA, by fusing GFP to PA-binding domains, has provided direct evidence for PA dynamics in different intracellular compartments. Here, three PA sensors were characterized in vitro, and their preferences for different PA species in particular lipidic environments were compared. In addition, the localization of PA in macrophages during frustrated phagocytosis was examined using these PA sensors and was combined with a lipidomic analysis of PA in intracellular compartments. The results indicate that the PA sensors display some preferences for specific PA species, depending on the lipid environment, and the localization study in macrophages revealed the complexity of intracellular PA dynamics. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
Psychometric properties of Frustration Discomfort Scale in a Turkish sample.
Ozer, Bilge Uzun; Demir, Ayhan; Harrington, Neil
2012-08-01
The present study assessed the psychometric properties of the Frustration Discomfort Scale for Turkish college students. The Frustration Discomfort Scale (FDS), Procrastination Assessment Scale-Student, and Rosenberg Self-Esteem Scale were administered to a sample of 171 (98 women, 73 men) Turkish college students. The results of the confirmatory factor analysis yielded fit index values demonstrating viability of the four-dimensional solution as in the original. Findings also revealed that, as predicted, the Discomfort Intolerance subscale of Turkish FDS was most strongly correlated with procrastination. Overall results provided evidence for the factor validity and reliability of the Turkish version of the scale for use in a Turkish population.
Wu, Qi-Long; Han, Song-De; Wang, Qing-Lun; Zhao, Jiong-Peng; Ma, Feng; Jiang, Xue; Liu, Fu-Chen; Bu, Xian-He
2015-10-25
Linking magnetically frustrated triangular FeO units by divalent metal ions (M(II) = Fe(II) for 1, Mn(II) for 2) gives isostructural 1D spin chains. Strong antiferromagnetic interactions were found in these complexes with significant frustrations but very interesting ferrimagnetic like transition and metamagnetism were found in mixed valence 1. By comparing the magnetic behaviours with isostructural complex 3 (with M(II) = Mg(II)), it is proposed that the spins of Fe(II) ions and Mn(II) ions have ferromagnetic and antiferromagnetic contributions respectively.
Ising antiferromagnet on the Archimedean lattices.
Yu, Unjong
2015-06-01
Geometric frustration effects were studied systematically with the Ising antiferromagnet on the 11 Archimedean lattices using the Monte Carlo methods. The Wang-Landau algorithm for static properties (specific heat and residual entropy) and the Metropolis algorithm for a freezing order parameter were adopted. The exact residual entropy was also found. Based on the degree of frustration and dynamic properties, ground states of them were determined. The Shastry-Sutherland lattice and the trellis lattice are weakly frustrated and have two- and one-dimensional long-range-ordered ground states, respectively. The bounce, maple-leaf, and star lattices have the spin ice phase. The spin liquid phase appears in the triangular and kagome lattices.
Ising antiferromagnet on the Archimedean lattices
NASA Astrophysics Data System (ADS)
Yu, Unjong
2015-06-01
Geometric frustration effects were studied systematically with the Ising antiferromagnet on the 11 Archimedean lattices using the Monte Carlo methods. The Wang-Landau algorithm for static properties (specific heat and residual entropy) and the Metropolis algorithm for a freezing order parameter were adopted. The exact residual entropy was also found. Based on the degree of frustration and dynamic properties, ground states of them were determined. The Shastry-Sutherland lattice and the trellis lattice are weakly frustrated and have two- and one-dimensional long-range-ordered ground states, respectively. The bounce, maple-leaf, and star lattices have the spin ice phase. The spin liquid phase appears in the triangular and kagome lattices.
Bianchi, Clélia M; Huneau, Jean-François; Le Goff, Gaëlle; Verger, Eric O; Mariotti, François; Gurviez, Patricia
2016-10-12
From a life course perspective, pregnancy leads to a rise in nutrition awareness and an increase in information flow in favour of adopting healthier eating behaviours. This qualitative study was designed to better understand the determinants of eating behaviours in French pregnant women by focusing on their concerns, attitudes and beliefs and their nutrition-related information seeking practices. Seven focus groups were conducted, involving a total of 40 French pregnant women. An inductive thematic approach, adapted from the grounded theory, was adopted to analyse the data. Two major themes were identified: eating behaviour and nutrition-related information behaviour. The eating behaviour theme was divided into four sub-themes using the attribution theory. Three external causes affected the eating behaviour of pregnant women (food restrictions, physiological changes and weight gain), and led to frustration and a perceived loss of control. By contrast the adoption of a healthier diet was perceived as internal by pregnant women, and resulted in self-fulfilment and empowerment regarding the health and the well-being of their baby and themselves, and their weight gain management. Greater attention was paid to nutrition-related information obtained from healthcare providers, the social environment and the mass media. Information was passively absorbed or actively sought by pregnant women, but most was perceived as contradictory, which led to confusion. Pregnancy is accompanied by a rise in nutrition awareness, substantiated by eating behaviour modifications due to external and internal causes. However, conflicts between and within information sources result in confusion that can limit the adoption of healthier eating behaviour.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fredrickson, Daniel C
2015-06-23
Final technical report for "Chemical Frustration: A Design Principle for the Discovery of New Complex Alloy and Intermetallic Phases" funded by the Office of Science through the Materials Chemistry Program of the Office of Basic Energy Sciences.
Retest Reliability of the Rosenzweig Picture-Frustration Study and Similar Semiprojective Techniques
ERIC Educational Resources Information Center
Rosenzweig, Saul; And Others
1975-01-01
The research dealing with the reliability of the Rosenzweig Picture-Frustration Study is surveyed. Analysis of various split-half, and retest procedures are reviewed and their relative effectiveness evaluated. Reliability measures as applied to projective techniques in general are discussed. (Author/DEP)
Physiological and Emotional Reactivity to Learning and Frustration
ERIC Educational Resources Information Center
Lewis, Michael; Hitchcock, Daniel F. A.; Sullivan, Margaret Wolan
2004-01-01
This study examined the behavioral (arm, facial) and autonomic (heart rate, respiratory sinus arrhythmia [RSA], and adrenocortical axis) reactivity of 56 4-month-old infants in response to contingency learning and extinction-induced frustration. During learning, infants displayed increases in operant arm response and positive emotional…
Unanue, Wenceslao; Rempel, Konrad; Gómez, Marcos E; Van den Broeck, Anja
2017-01-01
Materialistic values may be detrimental for people's well-being. However, we know little about why (i.e., explaining mechanisms) and when (i.e., boundary conditions) this is the case. Although low satisfaction of the psychological needs is said to play a key role in this process, a recent meta-analysis indicates that the explaining power of need satisfaction is limited and suggests that need frustration may be more important. Moreover, although materialism may be detrimental in some life domains, studies in materialistic contexts such as work are lacking, particularly in the non-Western world. In response, we put need frustration to the fore and examine both need satisfaction and frustration as the underlying processes in the relation between materialism and employee attitudes and well-being in two Latin-American countries. The Chilean sample ( N = 742) shows that materialism at work is associated with less positive (work satisfaction and engagement) and more negative (burnout and turnover intentions) outcomes, even when controlling for workers' income. Notably, need frustration explained the detrimental effects of materialism alongside need satisfaction in a unique manner, showing that it is essential to distinguish both constructs. Results were replicated in Paraguay ( N = 518) using different positive (organizational commitment and meaning at work) and negative (negative emotions and job insecurity) outcomes, adding to the generalizability of our results across samples of different nations.
The nature of geometric frustration in the Kob-Andersen mixture
NASA Astrophysics Data System (ADS)
Crowther, Peter; Turci, Francesco; Royall, C. Patrick
2015-07-01
Geometric frustration is an approach to the glass transition based upon the consideration of locally favoured structures (LFS), which are geometric motifs which minimise the local free energy. Geometric frustration proposes that a transition to a crystalline state is frustrated because these LFS do not tile space. However, this concept is based on icosahedra which are not always the LFS for a given system. The LFS of the popular Kob-Andersen (KA) model glassformer are the bicapped square antiprism, which does tile space. Such a LFS-crystal is indeed realised in the Al2Cu structure, which is predicted to be a low energy state for the KA model with a 2:1 composition. We, therefore, hypothesise that upon changing the composition in the KA model towards 2:1, geometric frustration may be progressively relieved, leading to larger and larger domains of LFS which would ultimately correspond to the Al2Cu crystal. Remarkably, rather than an increase, upon changing composition we find a small decrease in the LFS population, and the system remains impervious to nucleation of LFS crystals. We suggest that this may be related to the composition of the LFS, as only a limited subset is compatible with the crystal. We further demonstrate that the Al2Cu crystal will grow from a seed in the KA model with 2:1 composition and identify the melting temperature to be 0.447(2).
Temperament, Executive Control, and ADHD across Early Development
Rabinovitz, Beth B.; O’Neill, Sarah; Rajendran, Khushmand; Halperin, Jeffrey M.
2015-01-01
Research examining factors linking early temperament and later ADHD is limited by cross-sectional approaches and having the same informant rate both temperament and psychopathology. We used multi-informant/multi-method longitudinal data to test the hypothesis that negative emotionality during preschool is positively associated with ADHD symptom severity in middle childhood, but developing executive control mediates this relation. Children (N=161) with and without ADHD were evaluated three times: Parent and teacher temperament ratings and NEPSY Visual Attention at ages 3–4 years; WISC-IV Working Memory Index and NEPSY Response Set at age 6 years; and ADHD symptoms using the Kiddie-SADS at age 7 years. Parent and teacher ratings of preschoolers’ temperament were combined to form an Anger/Frustration composite. Similarly, an Executive Functioning composite was derived from age 6 measures. Bootstrapping was used to determine whether age 6 Executive Functioning mediated the relation between early Anger/Frustration and later ADHD symptom severity, while controlling for early executive functioning. Preschoolers’ Anger/Frustration was significantly associated with later ADHD symptoms, with this relation partially mediated by age 6 Executive Functioning. Developing executive control mediates the relation between early Anger/Frustration and later ADHD symptom severity, suggesting that Anger/Frustration influences ADHD symptom severity through its impact on developing executive control. Early interventions targeting the harmful influences of negative emotionality or enhancing executive functioning may diminish later ADHD severity. PMID:26854505
Switchable geometric frustration in an artificial-spin-ice-superconductor heterosystem.
Wang, Yong-Lei; Ma, Xiaoyu; Xu, Jing; Xiao, Zhi-Li; Snezhko, Alexey; Divan, Ralu; Ocola, Leonidas E; Pearson, John E; Janko, Boldizsar; Kwok, Wai-Kwong
2018-06-11
Geometric frustration emerges when local interaction energies in an ordered lattice structure cannot be simultaneously minimized, resulting in a large number of degenerate states. The numerous degenerate configurations may lead to practical applications in microelectronics 1 , such as data storage, memory and logic 2 . However, it is difficult to achieve very high degeneracy, especially in a two-dimensional system 3,4 . Here, we showcase in situ controllable geometric frustration with high degeneracy in a two-dimensional flux-quantum system. We create this in a superconducting thin film placed underneath a reconfigurable artificial-spin-ice structure 5 . The tunable magnetic charges in the artificial-spin-ice strongly interact with the flux quanta in the superconductor, enabling switching between frustrated and crystallized flux quanta states. The different states have measurable effects on the superconducting critical current profile, which can be reconfigured by precise selection of the spin-ice magnetic state through the application of an external magnetic field. We demonstrate the applicability of these effects by realizing a reprogrammable flux quanta diode. The tailoring of the energy landscape of interacting 'particles' using artificial-spin-ices provides a new paradigm for the design of geometric frustration, which could illuminate a path to control new functionalities in other material systems, such as magnetic skyrmions 6 , electrons and holes in two-dimensional materials 7,8 , and topological insulators 9 , as well as colloids in soft materials 10-13 .
Small Town Science Policy: Bringing Our Expertise Back Home
NASA Astrophysics Data System (ADS)
Larsen, K. W.
2017-12-01
Questions of science policy are more and more in the news, whether it is in regards to our nation's role in international agreements (Paris Climate Accords), the disbursement of limited research budgets, or a hundred other national issues. Influencing these decisions is a difficult, frustrating, and often ineffective endeavor. Where we can have a greater impact is by effecting change locally, either through interactions with and education of local elected officials or direct involvement in the political process. Advocating for scientifically sound policy at this level takes a different set of communication skills, but can ultimately reach a wider audience and have tangible effects.
Violence and Aggression in Children and Youth. ERIC/OSEP Digest E572.
ERIC Educational Resources Information Center
Fitzsimmons, Mary K.
This digest discusses the need for troubled students to receive habilitative services instead of haphazard punishment, then outlines sources of frustration for aggressive students and stages of frustration (anxiety, stress, defensiveness, physical aggression, and tension reduction), and appropriate responses. Teachers are advised to prevent…
Academic Culture in Malaysia: Sources of Satisfaction and Frustration
ERIC Educational Resources Information Center
Da Wan, Chang; Chapman, David W.; Zain, Ahmad Nurulazam Md; Hutcheson, Sigrid; Lee, Molly; Austin, Ann E.
2015-01-01
This paper examines the sources of satisfaction and frustration among Malaysian academics across three types of higher education institutions (HEIs)--public research university, public comprehensive university and private non-profit university. Based on interview with 67 academics across six HEIs, there is a clear pattern and relationship between…
Decreasing Anxiety and Frustration in the Spanish Language Classroom.
ERIC Educational Resources Information Center
Haskin, Joanna; Smith, Maria de Lourdes Hernandez; Racine, Margaret
This report describes instructional strategies to decrease anxiety and frustration in the Spanish classroom. Participants were five 7th grade Spanish classes in two suburban middle schools. Student interventions included a study skills guide; partner and group presentations, skits, and activities; and group oral reading. Teacher interventions…
ERIC Educational Resources Information Center
Kosmoski, Georgia J.; Pollack, Dennis R.
2005-01-01
The second edition of this best-selling resource provides new and updated content influenced by the feedback of over 250 school administrators. "Managing Difficult, Frustrating, and Hostile Conversations" uncovers safe and effective strategies for dispelling common sensitive situations such as handling legitimate complaints, controlling those…
Teaching Energy Geography? It's Complicated
ERIC Educational Resources Information Center
Huber, Matt
2016-01-01
The premise of this essay is that energy geographies are complicated, and this in itself presents some pedagogical difficulties. As someone who wants students to critically examine and confront the complexity of energy systems, it can be frustrating when students react to demonstrate frustration, apathy, or even confusion. In what follows, I will…
A Validation Study of the Existential Anxiety Scale.
ERIC Educational Resources Information Center
Hullett, Michael A.
Logotherapy is a meaning-centered psychotherapy which focuses on both the meaning of human existence and the personal search for meaning. If the will to search for meaning is frustrated, "existential frustration" may result. This study validates the Existential Anxiety Scale (EAS) developed by Good and Good (1974). Basic principles of…
Soft, Transparent, Electronic Skin for Distributed and Multiple Pressure Sensing
Levi, Alessandro; Piovanelli, Matteo; Furlan, Silvano; Mazzolai, Barbara; Beccai, Lucia
2013-01-01
In this paper we present a new optical, flexible pressure sensor that can be applied as smart skin to a robot or to consumer electronic devices. We describe a mechano-optical transduction principle that can allow the encoding of information related to an externally applied mechanical stimulus, e.g., contact, pressure and shape of contact. The physical embodiment that we present in this work is an electronic skin consisting of eight infrared emitters and eight photo-detectors coupled together and embedded in a planar PDMS waveguide of 5.5 cm diameter. When a contact occurs on the sensing area, the optical signals reaching the peripheral detectors experience a loss because of the Frustrated Total Internal Reflection and deformation of the material. The light signal is converted to electrical signal through an electronic system and a reconstruction algorithm running on a computer reconstructs the pressure map. Pilot experiments are performed to validate the tactile sensing principle by applying external pressures up to 160 kPa. Moreover, the capabilities of the electronic skin to detect contact pressure at multiple subsequent positions, as well as its function on curved surfaces, are validated. A weight sensitivity of 0.193 gr−1 was recorded, thus making the electronic skin suitable to detect pressures in the order of few grams. PMID:23686140
Jäger, B; Schmid-Ott, G; Ernst, G; Dölle-Lange, E; Sack, M
2012-06-01
The aim of this study was to construct and validate a short self-rating questionnaire for the assessment of ego functions and ability of self regulation. An item pool of 120 items covering 6 postulated dimensions was reduced by two steps in independent samples (n = 136 + 470) via factor and item analyses to the final version consisting of 35 items. The 5 resulting questionnaire scales "interpersonal disturbances", "frustration tolerance and impulse control", "identity disturbances", "affect differentiation and affect tolerance" and "self-esteem" were well interpretable and showed in confirmatory factor analysis the best fit to the data (CHI²/df = 3.48; RMSEA = 0.73). Total scores were found to differentiate well between diagnostic groups of patients with more or less ego pathology (FANOVA = 9.8; df = 11; p < 0.001), thus proving good concurrent validity. Reliability was shown by testing internal consistency and test-retest correlations. The "Hannover self-regulation questionnaire" (HSRQ) evidently is an appropriate and reliable screening instrument in order to assess ego functions and capacities of self regulation in an economic and user-friendly means. The scale structure allows differentiated diagnostics of weak vs. stable ego functions and may be used for detailed therapy planning. © Georg Thieme Verlag KG Stuttgart · New York.
Castillo Aguilar, Juan Jesús; Cabrera Carrillo, Juan Antonio; Guerra Fernández, Antonio Jesús; Postigo Pozo, Sergio
2017-01-01
Tire characteristics and behavior are of great importance in vehicle dynamics since the forces transmitted in the tire-road contact are the main contributors to global vehicle performance. Several research groups have focused on the study and modeling of tires. Some of the most important factors that need to be known are tread characteristics and pressure distribution in the tire-ground contact patch. In this work, a test bench has been used to adequately determine the aforementioned factors. The measurement principle of the test bench is the frustration of total internal reflection (FTIR) of light. It makes use of a laterally illuminated glass on which the tire leans. An interposed plastic interface between them causes the reflection of light. Finally, a video camera captures the bright image formed through the glass. The brightness level in each pixel of the image is related to existing normal pressure. A study of the parameters that affect the test bench calibration such as type of interface material used, diffuse light, hysteresis, creep and transverse light absorption is performed. Experimental tests are conducted to relate tire inflation pressure and camber angle to the pressure distribution. Furthermore, the test bench is used to detect and evaluate the influence of defects in the tire on the contact pressures. PMID:28353674
Castillo Aguilar, Juan Jesús; Cabrera Carrillo, Juan Antonio; Guerra Fernández, Antonio Jesús; Postigo Pozo, Sergio
2017-03-29
Tire characteristics and behavior are of great importance in vehicle dynamics since the forces transmitted in the tire-road contact are the main contributors to global vehicle performance. Several research groups have focused on the study and modeling of tires. Some of the most important factors that need to be known are tread characteristics and pressure distribution in the tire-ground contact patch. In this work, a test bench has been used to adequately determine the aforementioned factors. The measurement principle of the test bench is the frustration of total internal reflection (FTIR) of light. It makes use of a laterally illuminated glass on which the tire leans. An interposed plastic interface between them causes the reflection of light. Finally, a video camera captures the bright image formed through the glass. The brightness level in each pixel of the image is related to existing normal pressure. A study of the parameters that affect the test bench calibration such as type of interface material used, diffuse light, hysteresis, creep and transverse light absorption is performed. Experimental tests are conducted to relate tire inflation pressure and camber angle to the pressure distribution. Furthermore, the test bench is used to detect and evaluate the influence of defects in the tire on the contact pressures.
Glassiness versus Order in Densely Frustrated Josephson Arrays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gupta, P.; Teitel, S.; Gingras, M.J.
1998-01-01
We carry out extensive Monte Carlo simulations of the Coulomb gas dual to the uniformly frustrated two-dimensional XY model, for a sequence of frustrations f converging to the irrational (3{minus}{radical}(5))/ 2. We find in these systems a sharp first order equilibrium phase transition to an ordered vortex structure at a T{sub c} which varies only slightly with f . This ordered vortex structure remains, in general, phase incoherent until a lower vortex pinning transition T{sub p}(f) that varies with f. We argue that the glassy behaviors reported for this model in earlier simulations are dynamic effects. {copyright} {ital 1997} {italmore » The American Physical Society}« less
What Influences Social Workers’ Attitudes Toward Working With Clients With Severe Mental Illness?
Eack, Shaun M.; Newhill, Christina E.
2013-01-01
A national random survey of 2000 NASW members in post-master’s practice in mental health was conducted to investigate their experiences with and attitudes about working with individuals with severe and persistent mental illness (SPMI). Through a series of structural equation models, we examined the influence of different frustrations reported by the respondents on their attitudes toward working with individuals with SPMI. Results suggest that social workers’ attitudes toward working with individuals with SPMI are primarily influenced by their frustrations related to client behaviors and treatment issues, rather than frustrations with system related issues. Implications for social work practice and directions for future research are discussed. (105 words) PMID:24353397
Frustration relieved ferrimagnetism in novel A- and B-site-ordered quadruple perovskite.
Chen, Wei-tin; Mizumaki, Masaichiro; Saito, Takashi; Shimakawa, Yuichi
2013-07-28
A novel A- and B-site-ordered quadruple perovskite CaCu3Fe2Sb2O12 was obtained and it shows ferrimagnetism below about 170 K. The B-site Fe spin sublattice adapts a tetrahedral framework in a cubic structure and the Fe(3+)-Fe(3+) antiferromagnetic interaction can result in a geometrical spin frustration as seen in a simple perovskite Ca2FeSbO6. With the introduction of Cu(2+) into the A' site, the antiferromagnetic spin frustration is relieved by the strong Cu(2+)-Fe(3+) interaction, and a ferrimagnetic ordering appears at a much higher temperature than the spin-glass transition temperature.
Majumdar, Kingshuk
2011-03-23
The effects of interlayer coupling and spatial anisotropy on the spin-wave excitation spectra of a three-dimensional spatially anisotropic, frustrated spin-½ Heisenberg antiferromagnet (HAFM) are investigated for the two ordered phases using second-order spin-wave expansion. We show that the second-order corrections to the spin-wave energies are significant and find that the energy spectra of the three-dimensional HAFM have similar qualitative features to the energy spectra of the two-dimensional HAFM on a square lattice. We also discuss the features that can provide experimental measures for the strength of the interlayer coupling, spatial anisotropy parameter, and magnetic frustration.
ERIC Educational Resources Information Center
Ratto, Brooke Gilmore; Lynch, Andy
2012-01-01
Student and faculty frustrations with traditional higher education textbook models continue to escalate. These frustrations present an opportunity for academic libraries to forge partnerships with teaching faculty and vendors to repurpose existing library resources. Library and teaching faculty at Southern New Hampshire University collaborated to…
The Capstone Experience for the Religious Studies Major
ERIC Educational Resources Information Center
Upson-Saia, Kristi
2013-01-01
The purpose of this essay is to offer a survey of religious studies capstones from twenty-nine U.S. colleges and universities, to identify the most common frustrations about the capstone, and to observe how departments resolve such frustrations. I conclude that the most successful capstones--in terms of students' performance and faculty…
Superintendents' Frustration Grows, but Intangible Rewards Remain High
ERIC Educational Resources Information Center
Solomon, J. D.
2012-01-01
The nation's K12 school superintendents are increasingly fatigued and frustrated by pressures to accomplish more in their districts with less resources. For most, though, personal commitment to public education helps overcome sources of stress stemming from many aspects of their jobs. That is the top-level finding of the 2012 Public School…
ERIC Educational Resources Information Center
Del Valle, Milenko; Matos, Lennia; Díaz, Alejandro; Pérez, María Victoria; Vergara, Jorge
2018-01-01
This research work aims to analyze the psychometric properties of the Basic Psychological Needs Satisfaction and Frustration Scale (BPNSFS)--autonomy, competence and relatedness--identified by the self-determination theory (Deci & Ryan, 2000b), in a sample of 297 university students from different faculties and programs belonging to a Chilean…
ERIC Educational Resources Information Center
Deater-Deckard, Kirby; Petrill, Stephen A.; Thompson, Lee A.
2007-01-01
Background: Individual differences in conduct problems arise in part from proneness to anger/frustration and poor self-regulation of behavior. However, the genetic and environmental etiology of these connections is not known. Method: Using a twin design, we examined genetic and environmental covariation underlying the well-documented correlations…
ERIC Educational Resources Information Center
Zhou, Qing; Eisenberg, Nancy; Wang, Yun; Reiser, Mark
2004-01-01
Relations among authoritative and authoritarian parenting styles, children's effortful control and dispositional anger/frustration, and children's social functioning were examined for 425 first and second graders (7-10 years old) in Beijing, China. Parents reported on parenting styles; parents and teachers rated children's effortful control,…
Avoided criticality and slow relaxation in frustrated two-dimensional models
Esterlis, Ilya; Kivelson, Steven A.; Tarjus, Gilles
2017-10-23
Here, frustration and the associated phenomenon of “avoided criticality” have been proposed as an explanation for the dramatic relaxation slowdown in glass-forming liquids. To test this, we have undertaken a Monte Carlo study of possibly the simplest such problem, the two-dimensional XY model with frustration corresponding to a small flux f per plaquette. At f = 0, there is a Berezinskii-Kosterlitz-Thouless transition at T*, but at any small but nonzero f, this transition is avoided and replaced (presumably) by a vortex-ordering transition at much lower temperatures. We thus have studied the evolution of the dynamics for small and moderate fmore » as the system is cooled from above T* to below. Although we do find strongly temperature-dependent slowing of the dynamics as T crosses T* and that simultaneously the dynamics becomes more complex, neither effect is anywhere nearly as dramatic as the corresponding phenomena in glass-forming liquids. At the very least, this implies that the properties of supercooled liquids must depend on more than frustration and the existence of an avoided transition.« less
Cheon, Sung Hyeon; Reeve, Johnmarshall; Song, Yong-Gwan
2016-06-01
Intervention-induced gains in need satisfaction decrease PE students' amotivation. The present study adopted a dual-process model to test whether an intervention could also decrease need frustration and hence provide a second supplemental source to further decrease students' PE amotivation. Using an experimental, longitudinal research design, 19 experienced PE teachers (9 experimental, 10 control) and their 1,017 students participated in an intervention program to help teachers become both more autonomy supportive and less controlling. Multilevel repeated measures analyses showed that students of teachers in the experimental group reported greater T2, T3, and T4 perceived autonomy support, need satisfaction, and engagement and lesser T2, T3, and T4 perceived teacher control, need frustration, and amotivation than did students of teachers in the control group. Multilevel structural equation modeling analyses confirmed the hypothesized dual-process model in which both intervention-induced increases in need satisfaction and intervention-induced decreases need frustration decreased students' end-of-semester amotivation. We discuss the theoretical and practical implications of this new finding on the dual antecedents of diminished amotivation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cashman, Derek J.; Zhu, Tuo; Simmerman, Richard F.
2014-08-01
The stromal domain (PsaC, PsaD, and PsaE) of photosystem I (PSI) reduces transiently bound ferredoxin (Fd) or flavodoxin. Experimental structures exist for all of these protein partners individually, but no experimental structure of the PSI/Fd or PSI/flavodoxin complexes is presently available. Molecular models of Fd docked onto the stromal domain of the cyanobacterial PSI site are constructed here utilizing X-ray and NMR structures of PSI and Fd, respectively. Moreover, predictions of potential protein-protein interaction regions are based on experimental site-directed mutagenesis and cross-linking studies to guide rigid body docking calculations of Fd into PSI, complemented by energy landscape theory tomore » bring together regions of high energetic frustration on each of the interacting proteins. Results identify two regions of high localized frustration on the surface of Fd that contain negatively charged Asp and Glu residues. Our study predicts that these regions interact predominantly with regions of high localized frustration on the PsaC, PsaD, and PsaE chains of PSI, which include several residues predicted by previous experimental studies.« less
4-spin plaquette singlet state in the Shastry-Sutherland compound SrCu2(BO3)2
NASA Astrophysics Data System (ADS)
Zayed, M. E.; Rüegg, Ch.; Larrea J., J.; Läuchli, A. M.; Panagopoulos, C.; Saxena, S. S.; Ellerby, M.; McMorrow, D. F.; Strässle, Th.; Klotz, S.; Hamel, G.; Sadykov, R. A.; Pomjakushin, V.; Boehm, M.; Jiménez-Ruiz, M.; Schneidewind, A.; Pomjakushina, E.; Stingaciu, M.; Conder, K.; Rønnow, H. M.
2017-10-01
The study of interacting spin systems is of fundamental importance for modern condensed-matter physics. On frustrated lattices, magnetic exchange interactions cannot be simultaneously satisfied, and often give rise to competing exotic ground states. The frustrated two-dimensional Shastry-Sutherland lattice realized by SrCu2(BO3)2 (refs ,) is an important test case for our understanding of quantum magnetism. It was constructed to have an exactly solvable 2-spin dimer singlet ground state within a certain range of exchange parameters and frustration. While the exact dimer state and the antiferromagnetic order at both ends of the phase diagram are well known, the ground state and spin correlations in the intermediate frustration range have been widely debated. We report here the first experimental identification of the conjectured plaquette singlet intermediate phase in SrCu2(BO3)2. It is observed by inelastic neutron scattering after pressure tuning to 21.5 kbar. This gapped singlet state leads to a transition to long-range antiferromagnetic order above 40 kbar, consistent with the existence of a deconfined quantum critical point.
Geometric frustration and compatibility conditions for two-dimensional director fields.
Niv, Idan; Efrati, Efi
2018-01-17
Bent core (or banana shaped) liquid-crystal-forming-molecules locally favor an ordered state of zero splay and constant bend. Such a state, however, cannot be realized in the plane and the resulting liquid-crystalline phase is frustrated and must exhibit some compromise of these two mutually contradicting local intrinsic tendencies. This constitutes one of the most well-studied examples in which the intrinsic geometry of the constituents of a material gives rise to a geometrically frustrated assembly. Such geometric frustration is not only natural and ubiquitous but also leads to a striking variety of morphologies of ground states and exotic response properties. In this work we establish the necessary and sufficient conditions for two scalar functions, s and b to describe the splay and bend of a director field in the plane. We generalize these compatibility conditions for geometries with non-vanishing constant Gaussian curvature, and provide a reconstruction formula for the director field depending only on the splay and bend fields and their derivatives. Finally, we discuss optimal compromises for simple incompatible cases where the locally preferred values of the splay and bend cannot be simultaneously achieved.
NASA Astrophysics Data System (ADS)
Jurčišinová, E.; Jurčišin, M.
2018-05-01
We investigate in detail the process of formation of the multipeak low-temperature structure in the behavior of the specific heat capacity in frustrated magnetic systems in the framework of the exactly solvable antiferromagnetic spin-1 /2 Ising model with the multisite interaction in the presence of the external magnetic field on the kagome-like Husimi lattice. The behavior of the entropy of the model is studied and exact values of the residual entropies of all ground states are found. It is shown that the multipeak structure in the behavior of the specific heat capacity is related to the formation of the multilevel hierarchical ordering in the system of all ground states of the model. Direct relation between the maximal number of peaks in the specific heat capacity behavior and the number of independent interactions in studied frustrated magnetic system is identified. The mechanism of the formation of the multipeak structure in the specific heat capacity is described and studied in detail, and it is generalized to frustrated magnetic systems with arbitrary numbers of independent interactions.
Unanue, Wenceslao; Rempel, Konrad; Gómez, Marcos E.; Van den Broeck, Anja
2017-01-01
Materialistic values may be detrimental for people’s well-being. However, we know little about why (i.e., explaining mechanisms) and when (i.e., boundary conditions) this is the case. Although low satisfaction of the psychological needs is said to play a key role in this process, a recent meta-analysis indicates that the explaining power of need satisfaction is limited and suggests that need frustration may be more important. Moreover, although materialism may be detrimental in some life domains, studies in materialistic contexts such as work are lacking, particularly in the non-Western world. In response, we put need frustration to the fore and examine both need satisfaction and frustration as the underlying processes in the relation between materialism and employee attitudes and well-being in two Latin–American countries. The Chilean sample (N = 742) shows that materialism at work is associated with less positive (work satisfaction and engagement) and more negative (burnout and turnover intentions) outcomes, even when controlling for workers’ income. Notably, need frustration explained the detrimental effects of materialism alongside need satisfaction in a unique manner, showing that it is essential to distinguish both constructs. Results were replicated in Paraguay (N = 518) using different positive (organizational commitment and meaning at work) and negative (negative emotions and job insecurity) outcomes, adding to the generalizability of our results across samples of different nations. PMID:29066992
Larche, Chanel J; Musielak, Natalia; Dixon, Mike J
2017-06-01
Like many gambling games, the exceedingly popular and lucrative smartphone game "Candy Crush" features near-miss outcomes. In slot machines, a near-miss involves getting two of the needed three high-paying symbols on the pay-line (i.e., just missing the big win). In Candy Crush, the game signals when you just miss getting to the next level by one or two moves. Because near-misses in gambling games have consistently been shown to invigorate play despite being frustrating outcomes, the goal of the present study was to examine whether such near-misses trigger increases in player arousal, frustration and urge to continue play in Candy Crush. Sixty avid Candy Crush players were recruited to play the game for 30 min while having their Heart Rate, Skin Conductance Level, subjective arousal, frustration and urge to play recorded for three types of outcomes: wins (where they level up), losses (where they don't come close to levelling up), and near-misses (where they just miss levelling up). Near-misses were more arousing than losses as indexed by increased heart rate and greater subjective arousal. Near-misses were also subjectively rated as the most frustrating of all outcomes. Most importantly, of any type of outcome, near-misses triggered the most substantial urge to continue play. These findings suggest that near-misses in Candy Crush play a role in player commitment to the game, and may contribute to players playing longer than intended.
Affect-Aware Adaptive Tutoring Based on Human-Automation Etiquette Strategies.
Yang, Euijung; Dorneich, Michael C
2018-06-01
We investigated adapting the interaction style of intelligent tutoring system (ITS) feedback based on human-automation etiquette strategies. Most ITSs adapt the content difficulty level, adapt the feedback timing, or provide extra content when they detect cognitive or affective decrements. Our previous work demonstrated that changing the interaction style via different feedback etiquette strategies has differential effects on students' motivation, confidence, satisfaction, and performance. The best etiquette strategy was also determined by user frustration. Based on these findings, a rule set was developed that systemically selected the proper etiquette strategy to address one of four learning factors (motivation, confidence, satisfaction, and performance) under two different levels of user frustration. We explored whether etiquette strategy selection based on this rule set (systematic) or random changes in etiquette strategy for a given level of frustration affected the four learning factors. Participants solved mathematics problems under different frustration conditions with feedback that adapted dynamic changes in etiquette strategies either systematically or randomly. The results demonstrated that feedback with etiquette strategies chosen systematically via the rule set could selectively target and improve motivation, confidence, satisfaction, and performance more than changing etiquette strategies randomly. The systematic adaptation was effective no matter the level of frustration for the participant. If computer tutors can vary the interaction style to effectively mitigate negative emotions, then ITS designers would have one more mechanism in which to design affect-aware adaptations that provide the proper responses in situations where human emotions affect the ability to learn.
Emergence of low noise frustrated states in E/I balanced neural networks.
Recio, I; Torres, J J
2016-12-01
We study emerging phenomena in binary neural networks where, with a probability c synaptic intensities are chosen according with a Hebbian prescription, and with probability (1-c) there is an extra random contribution to synaptic weights. This new term, randomly taken from a Gaussian bimodal distribution, balances the synaptic population in the network so that one has 80%-20% relation in E/I population ratio, mimicking the balance observed in mammals cortex. For some regions of the relevant parameters, our system depicts standard memory (at low temperature) and non-memory attractors (at high temperature). However, as c decreases and the level of the underlying noise also decreases below a certain temperature T t , a kind of memory-frustrated state, which resembles spin-glass behavior, sharply emerges. Contrary to what occurs in Hopfield-like neural networks, the frustrated state appears here even in the limit of the loading parameter α→0. Moreover, we observed that the frustrated state in fact corresponds to two states of non-vanishing activity uncorrelated with stored memories, associated, respectively, to a high activity or Up state and to a low activity or Down state. Using a linear stability analysis, we found regions in the space of relevant parameters for locally stable steady states and demonstrated that frustrated states coexist with memory attractors below T t . Then, multistability between memory and frustrated states is present for relatively small c, and metastability of memory attractors can emerge as c decreases even more. We studied our system using standard mean-field techniques and with Monte Carlo simulations, obtaining a perfect agreement between theory and simulations. Our study can be useful to explain the role of synapse heterogeneity on the emergence of stable Up and Down states not associated to memory attractors, and to explore the conditions to induce transitions among them, as in sleep-wake transitions. Copyright © 2016 Elsevier Ltd. All rights reserved.
[Shaare Zedek Medical Center's model of an integrated division of internal medicine].
Yinnon, Amos M; Munter, Gabriel; Friedmann, Reuven; Katz, David; Nesher, Gideon; Tichler, Thomas; Zevin, Shoshana
2014-01-01
The specialty and practice of internal medicine have been subject to serious challenges in the last two decades. We describe the integrative model of internal medicine as developed in our hospital, providing solutions to some major challenges. Major components include: (1) Senior physicians and residents are employed by the Division rather than individual Departments of Medicine, allowing for balanced distribution of professional capabilities. (2) Two medical departments specialize in geriatric medicine, while the other departments take care of younger, more intellectually challenging patients. Senior and junior staff members rotate through these departments, allowing for exposure to different patient populations and professional expertise. (3) The backbone of senior physicians is rewarded by a set of incentives, including dedicated time for research. (4) Senior staff from the subspecialties contributes annually 1-2 months as senior physicians in the departments and receive academic and other compensation for their efforts. (5) In cases where medical departments elsewhere are flooded with corridor admissions (a source of frustration and burnout), a short admission unit in the emergency department relieves internal medicine pressures and shortens evaluation and therapy for many patients. Our integrative model of internal medicine allows for improved patient and staff distribution, greater satisfaction among patients and family members, greater professional satisfaction among physicians, while resident vacancies are filled with competent residents.
Data-Driven Learning of Total and Local Energies in Elemental Boron
NASA Astrophysics Data System (ADS)
Deringer, Volker L.; Pickard, Chris J.; Csányi, Gábor
2018-04-01
The allotropes of boron continue to challenge structural elucidation and solid-state theory. Here we use machine learning combined with random structure searching (RSS) algorithms to systematically construct an interatomic potential for boron. Starting from ensembles of randomized atomic configurations, we use alternating single-point quantum-mechanical energy and force computations, Gaussian approximation potential (GAP) fitting, and GAP-driven RSS to iteratively generate a representation of the element's potential-energy surface. Beyond the total energies of the very different boron allotropes, our model readily provides atom-resolved, local energies and thus deepened insight into the frustrated β -rhombohedral boron structure. Our results open the door for the efficient and automated generation of GAPs, and other machine-learning-based interatomic potentials, and suggest their usefulness as a tool for materials discovery.
Data-Driven Learning of Total and Local Energies in Elemental Boron.
Deringer, Volker L; Pickard, Chris J; Csányi, Gábor
2018-04-13
The allotropes of boron continue to challenge structural elucidation and solid-state theory. Here we use machine learning combined with random structure searching (RSS) algorithms to systematically construct an interatomic potential for boron. Starting from ensembles of randomized atomic configurations, we use alternating single-point quantum-mechanical energy and force computations, Gaussian approximation potential (GAP) fitting, and GAP-driven RSS to iteratively generate a representation of the element's potential-energy surface. Beyond the total energies of the very different boron allotropes, our model readily provides atom-resolved, local energies and thus deepened insight into the frustrated β-rhombohedral boron structure. Our results open the door for the efficient and automated generation of GAPs, and other machine-learning-based interatomic potentials, and suggest their usefulness as a tool for materials discovery.
The Application of Weikart's Theories in Teaching Non-English Speaking Students How to Read.
ERIC Educational Resources Information Center
Layton, Kent
Non-English speaking students of average intelligence experience extreme frustration when learning to read. The frustration is partly a result of simultaneous requirements to speak, read, listen, and write in the new language. It also is possible that the teaching methods and strategies employed by the teachers could be harmful to non-English…
Bullying among Girls in Japan and Hong Kong: An Examination of the Frustration-Aggression Model
ERIC Educational Resources Information Center
Tam, Frank Wai-ming; Taki, Mitsuru
2007-01-01
One widely accepted explanation of bullying, known as the aggressive-motive thesis, assumes that bullying is a form of aggressive behaviour triggered by external stress. However, recent evidences have suggested a different explanation, known as the frustration-aggression thesis, which asserts that bullying is a psychological defense triggered by…
Women who return to abusive relationships: a frustration for the critical care nurse.
Goss, G L; DeJoseph, J
1997-06-01
Nurses caring for abused women become frustrated and concerned when their patients return to the violent relationship. This disconcerted feeling can hinder the care nurses render to these women, subsequently leaving the victim powerless. Understanding this phenomenon can improve patient care, increase the image of women and, ultimately, help banish violence against women.
ERIC Educational Resources Information Center
Degnan, Kathryn A.; Calkins, Susan D.; Keane, Susan P.; Hill-Soderlund, Ashley L.
2008-01-01
Disruptive behavior, including aggression, defiance, and temper tantrums, typically peaks in early toddlerhood and decreases by school entry; however, some children do not show this normative decline. The current study examined disruptive behavior in 318 boys and girls at 2, 4, and 5 years of age and frustration reactivity, physiological…
ERIC Educational Resources Information Center
Misco, Thomas
2007-01-01
In this paper I convey a recurring problem and possible solution that arose during my doctoral research on the topic of cross-cultural Holocaust curriculum development for Latvian schools. Specifically, as I devised the methodology for my research, I experienced a number of frustrations concerning the issue of transferability and the limitations…
Can't Make 'em Do It: Sleeping, Eating, Toileting
ERIC Educational Resources Information Center
Duffy, Roslyn
2008-01-01
Sleeping, eating, and toileting battles frustrate most adults--mainly because they cannot make children do it. Falling asleep (or not) is within a child's control. The same is true for chewing and swallowing, or withholding and releasing urine and feces. Sleeping, Eating, and Toileting (S.E.T.) create lots of frustration. An exhausted adult wants…
ERIC Educational Resources Information Center
Coffland, David A.
2012-01-01
The combined seventh-grade and eighth-grade class began each day with a mathematical reasoning question as a warm-up activity. One day's question was: Is the product of two odd numbers always an odd number? The students took sides on the issue, and the exercise ended in frustration. Reflecting on the frustration caused by this warm-up activity,…
ERIC Educational Resources Information Center
Greenberg, Jan S.; And Others
1993-01-01
Used stress process model to investigate impact of later-life caregiving on 105 mothers of adult children with mental illness and 208 mothers of adult children with mental retardation. Mothers of persons with mental illness reported higher levels of frustrations and lower levels of gratifications. Adult child's behavior problems were strongest…
A Field-Tested Task Analysis for Creating Single-Subject Graphs Using Microsoft[R] Office Excel
ERIC Educational Resources Information Center
Lo, Ya-yu; Konrad, Moira
2007-01-01
Creating single-subject (SS) graphs is challenging for many researchers and practitioners because it is a complex task with many steps. Although several authors have introduced guidelines for creating SS graphs, many users continue to experience frustration. The purpose of this article is to minimize these frustrations by providing a field-tested…
Static holes in the geometrically frustrated bow-tie ladder
NASA Astrophysics Data System (ADS)
Martins, George B.; Brenig, Wolfram
2008-10-01
We investigate the doping of a geometrically frustrated spin ladder with static holes by a complementary approach using exact diagonalization and quantum dimers. Results for thermodynamic properties, the singlet density of states, the hole-binding energy and the spin correlations will be presented. For the undoped systems the ground state is non-degenerate, with translationally invariant nearest-neighbor spin correlations. For the doped case, we find that static holes polarize their vicinity through a localization of singlets, reducing the frustration. This polarization induces short range repulsive forces between two holes and an oscillatory behavior of the long range two-hole energy. For most quantities investigated, we find very good agreement between the quantum dimer approach and the results from exact diagonalization.
Infant pathways to externalizing behavior: evidence of Genotype x Environment interaction.
Leve, Leslie D; Kerr, David C R; Shaw, Daniel; Ge, Xiaojia; Neiderhiser, Jenae M; Scaramella, Laura V; Reid, John B; Conger, Rand; Reiss, David
2010-01-01
To further the understanding of the effects of early experiences, 9-month-old infants were observed during a frustration task. The analytical sample was composed of 348 linked triads of participants (adoptive parents, adopted child, and birth parent[s]) from a prospective adoption study. It was hypothesized that genetic risk for externalizing problems and affect dysregulation in the adoptive parents would independently and interactively predict a known precursor to externalizing problems: heightened infant attention to frustrating events. Results supported the moderation hypotheses involving adoptive mother affect dysregulation: Infants at genetic risk showed heightened attention to frustrating events only when the adoptive mother had higher levels of anxious and depressive symptoms. The Genotype x Environment interaction pattern held when substance use during pregnancy was considered.
Ge, Hongyu; Jing, Yuanyuan; Yang, Xinzheng
2016-12-05
A series of cobalt complexes with acylmethylpyridinol and aliphatic PNP pincer ligands are proposed based on the active site structure of [Fe]-hydrogenase. Density functional theory calculations indicate that the total free energy barriers of the hydrogenation of CO 2 and dehydrogenation of formic acid catalyzed by these Co complexes are as low as 23.1 kcal/mol in water. The acylmethylpyridinol ligand plays a significant role in the cleavage of H 2 by forming a strong Co-H δ- ···H δ+ -O dihydrogen bond in a fashion of frustrated Lewis pairs.
Internal Stresses Lead to Net Forces and Torques on Extended Elastic Bodies
NASA Astrophysics Data System (ADS)
Aharoni, Hillel; Kolinski, John M.; Moshe, Michael; Meirzada, Idan; Sharon, Eran
2016-09-01
A geometrically frustrated elastic body will develop residual stresses arising from the mismatch between the intrinsic geometry of the body and the geometry of the ambient space. We analyze these stresses for an ambient space with gradients in its intrinsic curvature, and show that residual stresses generate effective forces and torques on the center of mass of the body. We analytically calculate these forces in two dimensions, and experimentally demonstrate their action by the migration of a non-Euclidean gel disc in a curved Hele-Shaw cell. An extension of our analysis to higher dimensions shows that these forces are also generated in three dimensions, but are negligible compared to gravity.
NASA Johnson Space Center: Total quality partnership
NASA Technical Reports Server (NTRS)
Harlan, Charlie; Boyd, Alfred A.
1992-01-01
The development of and benefits realized from a joint NASA, support contractor continuous improvement process at the Johnson Space Center (JSC) is traced. The joint effort described is the Safety, Reliability, and Quality Assurance Directorate relationship with its three support contractors which began in early 1990. The Continuous Improvement effort started in early 1990 with an initiative to document and simplify numerous engineering change evaluation processes. This effort quickly grew in scope and intensity to include process improvement teams, improvement methodologies, awareness, and training. By early 1991, the support contractor had teams in place and functioning, program goals established and a cultural change effort underway. In mid-l991 it became apparent that a major redirection was needed to counter a growing sense of frustration and dissatisfaction from teams and managers. Sources of frustration were isolated to insufficient joint participation on teams, and to a poorly defined vision. Over the next year, the effort was transformed to a truly joint process. The presentation covers the steps taken to define vision, values, goals, and priorities and to form a joint Steering Committee and joint process improvement teams. The most recent assessment against the President's award criteria is presented as a summary of progress. Small, but important improvement results have already demonstrated the value of the joint effort.
Bjørshol, Conrad Arnfinn; Myklebust, Helge; Nilsen, Kjetil Lønne; Hoff, Thomas; Bjørkli, Cato; Illguth, Eirik; Søreide, Eldar; Sunde, Kjetil
2011-02-01
The aim of this study was to evaluate whether socioemotional stress affects the quality of cardiopulmonary resuscitation during advanced life support in a simulated manikin model. A randomized crossover trial with advanced life support performed in two different conditions, with and without exposure to socioemotional stress. The study was conducted at the Stavanger Acute Medicine Foundation for Education and Research simulation center, Stavanger, Norway. Paramedic teams, each consisting of two paramedics and one assistant, employed at Stavanger University Hospital, Stavanger, Norway. A total of 19 paramedic teams performed advanced life support twice in a randomized fashion, one control condition without socioemotional stress and one experimental condition with exposure to socioemotional stress. The socioemotional stress consisted of an upset friend of the simulated patient who was a physician, spoke a foreign language, was unfamiliar with current Norwegian resuscitation guidelines, supplied irrelevant clinical information, and repeatedly made doubts about the paramedics' resuscitation efforts. Aural distractions were supplied by television and cell telephone. The primary outcome was the quality of cardiopulmonary resuscitation: chest compression depth, chest compression rate, time without chest compressions (no-flow ratio), and ventilation rate after endotracheal intubation. As a secondary outcome, the socioemotional stress impact was evaluated through the paramedics' subjective workload, frustration, and feeling of realism. There were no significant differences in chest compression depth (39 vs. 38 mm, p = .214), compression rate (113 vs. 116 min⁻¹, p = .065), no-flow ratio (0.15 vs. 0.15, p = .618), or ventilation rate (8.2 vs. 7.7 min⁻¹, p = .120) between the two conditions. There was a significant increase in the subjective workload, frustration, and feeling of realism when the paramedics were exposed to socioemotional stress. In this advanced life support manikin study, the presence of socioemotional stress increased the subjective workload, frustration, and feeling of realism, without affecting the quality of cardiopulmonary resuscitation.
Modica, Renee F; Lomax, Kathleen Graham; Batzel, Pamela; Shapardanis, Leah; Katzer, Kimberly Compton; Elder, Melissa E
2016-01-01
Children with systemic juvenile idiopathic arthritis (SJIA) often encounter a delay between symptom onset and disease diagnosis, partly due to the broad differential of fever and lack of symptom recognition by providers. Families often seek multiple medical opinions and post on social media about their frustrations. This linguistic analysis observed the changing language patterns and social media posting behaviors of parents in the time leading to, during, and after SJIA diagnosis. Public social media sites were manually reviewed by a linguistic team to evaluate posts about SJIA from US-based parents. A total of 3,979 posts between July 2001 and January 2015 were reviewed from 108 sites. Pre-SJIA diagnosis parents sought answers and shared status updates on social media, focusing primarily on the following three site types: alternative/natural lifestyle forums (39%), Facebook (27%), and disease-specific forums (17%). Posts during early prediagnosis phases were characterized by expressive language showing confidence in health care providers and trust in parental instincts. At later prediagnosis stages, parents continued to use social media, but the posts demonstrated increased frustration with delays in diagnosis and gaps in communication with providers. More objective symptom descriptions and a greatly reduced child-centered emotional focus were observed as parents shifted into caregiving roles. Once the diagnosis of SJIA was confirmed, parents used straightforward, less expressive language, and Facebook (47%) to make "announcement" posts and increased their use of SJIA websites (30%). With treatment initiation, the posts demonstrated a slow return of expressive language and an increased parental understanding of the "new normal". Parents use different language styles, frames of reference, and websites before and after SJIA diagnosis. Gaps in parent-provider communication, especially before diagnosis, and their new roles as caregivers lead to parental use of social media to express frustration with the health care process. Providers should tailor their discussions with parents to address these issues.
Perceived stress latent factors and the burnout subtypes: a structural model in dental students.
Montero-Marín, Jesús; Piva Demarzo, Marcelo Marcos; Stapinski, Lexine; Gili, Margarita; García-Campayo, Javier
2014-01-01
Students of health-professions suffer high levels of stress and burnout. The aim of the present study was to evaluate the relationship between perceived stress latent factors ('tenseness' and 'frustration') and the features ('overload', 'lack of development' and 'neglect') of the three burnout subtypes ('frenetic', 'under-challenged' and 'worn-out', respectively), in a sample of Spanish dental students. The study employed a cross-sectional design. A sample of Spanish dental students (n = 314) completed the 'Perceived Stress Questionnaire' and the 'Burnout Clinical Subtype Questionnaire Student Survey'. The associations among variables were observed by means of structural equation modelling using the unweighted least squares method from polychoric correlations. Strong associations among perceived stress factors and the burnout characteristics were observed, although a distinct pattern of relations was observed for each burnout subtype. The 'overload' was moderately and positively associated with both 'tenseness' (0.45), and 'frustration' (0.38) dimensions of perceived stress; the 'lack of development' was positively associated with the 'frustration' dimension (0.72), but negatively associated with 'tenseness' (-0.69); the 'neglect' showed a weaker positive associated with 'frustration' (0.41), and a small negative association with 'tenseness' (-0.20). The model was a very good fit to the data (GFI = 0.96; RSMR = 0.07; AGFI = 0.96; NFI = 0.95; RFI = 0.95). The stress factors of 'frustration' and 'tenseness' seems to be related in a distinct way to the burnout subtypes in Spanish dental students. This finding suggests that intervention programs specifically tailored to these subtypes may be a promising future direction.
Field-induced cluster spin glass and inverse symmetry breaking enhanced by frustration
NASA Astrophysics Data System (ADS)
Schmidt, M.; Zimmer, F. M.; Magalhaes, S. G.
2018-03-01
We consider a cluster disordered model to study the interplay between short- and long-range interactions in geometrically frustrated spin systems under an external magnetic field (h). In our approach, the intercluster long-range disorder (J) is analytically treated to get an effective cluster model that is computed exactly. The clusters follow a checkerboard lattice with first-neighbor (J1) and second-neighbor (J2) interactions. We find a reentrant transition from the cluster spin-glass (CSG) state to a paramagnetic (PM) phase as the temperature decreases for a certain range of h. This inverse symmetry breaking (ISB) appears as a consequence of both quenched disorder with frustration and h, that introduce a CSG state with higher entropy than the polarized PM phase. The competitive scenario introduced by antiferromagnetic (AF) short-range interactions increases the CSG state entropy, leading to continuous ISB transitions and enhancing the ISB regions, mainly in the geometrically frustrated case (J1 =J2). Remarkably, when strong AF intracluster couplings are present, field-induced CSG phases can be found. These CSG regions are strongly related to the magnetization plateaus observed in this cluster disordered system. In fact, it is found that each field-induced magnetization jump brings a CSG region. We notice that geometrical frustration, as well as cluster size, play an important role in the magnetization plateaus and, therefore, are also relevant in the field-induced glassy states. Our findings suggest that competing interactions support ISB and field-induced CSG phases in disordered cluster systems under an external magnetic field.
Mago, Rajnish; Fagiolini, Andrea; Weiller, Emmanuelle; Weiss, Catherine
2018-01-01
Despite the availability of effective antidepressants, about half of patients with major depressive disorder (MDD) display an inadequate response to their initial treatment. A large patient survey recently reported that 29.8% of MDD patients experiencing an inadequate treatment response felt frustrated about their medication and 19.2% were frustrated with their healthcare provider. This survey and chart audit evaluated healthcare professionals' (HCP) views on the emotional impact of having an inadequate response to antidepressant medication. HCPs who frequently treat patients with MDD completed a survey and chart audit of their MDD patients currently experiencing an inadequate response to antidepressant treatment. 287 HCPs completed 1336 chart audits. HCPs reported that 38% of their patients were trusting/accepting of their MDD medications and 41% of their patients trusted/felt confident with their healthcare provision. Conversely, HCPs reported that 11% of their patients were frustrated with their medication and 5% with their healthcare benefits. HCPs cited impact on daily life (53%) and treatment issues (lack of efficacy and side effects; 50%) as the main drivers for their patients' feelings of frustration. When HCPs recognized patients' feelings of frustration, the top concerns of the HCPs were worsening of symptoms (43%) and non-compliance (41%). This survey and chart audit highlights the emotional burden associated with inadequate responses to MDD treatment in addition to persistent symptoms. Differences between the views of the HCPs and patients are highlighted and suggest that HCPs may underestimate the full impact that having to try numerous medications has on their patients.
My Child Needs a Piece of Adaptive Equipment: Now What? Well, It Depends!
ERIC Educational Resources Information Center
Maly, Jennifer McLaughlin
2007-01-01
As a pediatric physical therapist, the author usually hears this question, "Now What?," after months of frustration as parents attempt to figure out the procedure of getting an item for their child. Unfortunately, there is not a specific answer except "it depends," which can be just as frustrating as the question at hand. Typically, a piece of…
Kinetically Inhibited Order in a Diamond-Lattice Antiferromagnet
DOE Office of Scientific and Technical Information (OSTI.GOV)
MacDougall, Gregory J; Gout, Delphine J; Zarestky, Jerel L
2011-01-01
Frustrated magnetic systems exhibit highly degenerate ground states and strong fluctuations, often leading to new physics. An intriguing example of current interest is the antiferromagnet on a diamond lattice, realized physically in the A-site spinel materials. This is a prototypical system in three dimensions where frustration arises from competing interactions rather than purely geometric constraints, and theory suggests the possibility of novel order at low temperature. Here we present a comprehensive single crystal neutron scattering study CoAl2O4, a highly frustrated A-site spinel. We observe strong diffuse scattering that peaks at wavevectors associated with Neel ordering. Below the temperature T*=6.5K, theremore » is a dramatic change in elastic scattering lineshape accompanied by the emergence of well-defined spin-wave excitations. T* had previously been associated with the onset of glassy behavior. Our new results suggest instead that in fact T* signifies a first-order phase transition, but with true long-range order inhibited by the kinetic freezing of domain walls. This scenario might be expected to occur widely in frustrated systems containing first-order phase transitions and is a natural explanation for existing reports of anomalous glassy behavior in other materials.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mahault, Benoit Alexandre; Saxena, Avadh Behari; Nisoli, Cristiano
We introduce a minimal agent-based model to qualitatively conceptualize the allocation of limited wealth among more abundant opportunities. We study the interplay of power, satisfaction and frustration in the problem of wealth distribution, concentration, and inequality. This framework allows us to compare subjective measures of frustration and satisfaction to collective measures of fairness in wealth distribution, such as the Lorenz curve and the Gini index. We find that a completely libertarian, law-of-the-jungle setting, where every agent can acquire wealth from, or lose wealth to, anybody else invariably leads to a complete polarization of the distribution of wealth vs. opportunity, onlymore » minimally ameliorated by disorder in a non-optimized society. The picture is however dramatically modified when hard constraints are imposed over agents, and they are forced to share wealth with neighbors on a network. We discuss the case of random networks and scale free networks. We then propose an out of equilibrium dynamics of the networks, based on a competition of power and frustration in the decision-making of agents that leads to network evolution. We show that the ratio of power and frustration controls different dynamical regimes separated by kinetic transition and characterized by drastically different values of the indices of equality.« less
Magnetic Fluctuations in the Hubbard Model on Kagome-based Frustrated Lattices
NASA Astrophysics Data System (ADS)
Udagawa, Masafumi; Motome, Yukitoshi
2008-03-01
We report our results on the interplay between electron correlation and magnetic fluctuations in the geometrically-frustrated Kagome and hyper-Kagome Hubbard models at half filling. These models have two different geometrical units important in the low-energy physics: the frustrated triangle and the non-frustrated loop with even-number sites. In order to treat both of them on equal footing, we apply cluster dynamical mean-field theory to large-size clusters up to 12 sites. By calculating the spin susceptibility χ(q, φ), we have found in the Kagome system that an anomalous one-dimensional magnetic correlation previously found near the Mott transition [1] is observed even in the non-interacting case at high temperature, and its temperature range gradually suppressed by increasing electron correlation. This behavior is ascribed to the nesting property at the van-Hove singularity preserved under electron correlation. We will also present the results for hyper-Kagome system in relation to the recent experiments on Na4Ir3O8 [2]. [1] T. Ohashi et al., Phys. Rev. Lett. 97, 066401 (2006)[2] Y. Okamoto et al., Phys. Rev. Lett. 99, 137207 (2007)
Adiabatic cooling processes in frustrated magnetic systems with pyrochlore structure
NASA Astrophysics Data System (ADS)
Jurčišinová, E.; Jurčišin, M.
2017-11-01
We investigate in detail the process of adiabatic cooling in the framework of the exactly solvable antiferromagnetic spin-1/2 Ising model in the presence of the external magnetic field on an approximate lattice with pyrochlore structure. The behavior of the entropy of the model is studied and exact values of the residual entropies of all ground states are found. The temperature variation of the system under adiabatic (de)magnetization is investigated and the central role of the macroscopically degenerated ground states in cooling processes is explicitly demonstrated. It is shown that the model parameter space of the studied geometrically frustrated system is divided into five disjunct regions with qualitatively different processes of the adiabatic cooling. The effectiveness of the adiabatic (de)magnetization cooling in the studied model is compared to the corresponding processes in paramagnetic salts. It is shown that the processes of the adiabatic cooling in the antiferromagnetic frustrated systems are much more effective especially in nonzero external magnetic fields. It means that the frustrated magnetic materials with pyrochlore structure can be considered as very promising refrigerants mainly in the situations with nonzero final values of the magnetic field.
NASA Astrophysics Data System (ADS)
Dönni, A.; Ehlers, G.; Maletta, H.; Fischer, P.; Kitazawa, H.; Zolliker, M.
1996-12-01
The heavy-fermion compound CePdAl with ZrNiAl-type crystal structure (hexagonal space group 0953-8984/8/50/043/img8) was investigated by powder neutron diffraction. The triangular coordination symmetry of magnetic Ce atoms on site 3f gives rise to geometrical frustration. CePdAl orders below 0953-8984/8/50/043/img9 with an incommensurate antiferromagnetic propagation vector 0953-8984/8/50/043/img10, and a longitudinal sine-wave (LSW) modulated spin arrangement. Magnetically ordered moments at Ce(1) and Ce(3) coexist with frustrated disordered moments at Ce(2). The experimentally determined magnetic structure is in agreement with group theoretical symmetry analysis considerations, calculated by the program MODY, which confirm that for Ce(2) an ordered magnetic moment parallel to the magnetically easy c-axis is forbidden by symmetry. Further low-temperature experiments give evidence for a second magnetic phase transition in CePdAl between 0.6 and 1.3 K. Magnetic structures of CePdAl are compared with those of the isostructural compound TbNiAl, where a non-zero ordered magnetic moment for the geometrically frustrated Tb(2) atoms is allowed by symmetry.
Adiabatic cooling processes in frustrated magnetic systems with pyrochlore structure.
Jurčišinová, E; Jurčišin, M
2017-11-01
We investigate in detail the process of adiabatic cooling in the framework of the exactly solvable antiferromagnetic spin-1/2 Ising model in the presence of the external magnetic field on an approximate lattice with pyrochlore structure. The behavior of the entropy of the model is studied and exact values of the residual entropies of all ground states are found. The temperature variation of the system under adiabatic (de)magnetization is investigated and the central role of the macroscopically degenerated ground states in cooling processes is explicitly demonstrated. It is shown that the model parameter space of the studied geometrically frustrated system is divided into five disjunct regions with qualitatively different processes of the adiabatic cooling. The effectiveness of the adiabatic (de)magnetization cooling in the studied model is compared to the corresponding processes in paramagnetic salts. It is shown that the processes of the adiabatic cooling in the antiferromagnetic frustrated systems are much more effective especially in nonzero external magnetic fields. It means that the frustrated magnetic materials with pyrochlore structure can be considered as very promising refrigerants mainly in the situations with nonzero final values of the magnetic field.
Benavent, Jose Vicente; Igual, Celedonia; Mora, Enrique; Antonio, Rosa; Tenias, Jose Maria
2016-12-01
The lack of specific prosthetic-related outcome instruments for Spanish amputees must be addressed. To elaborate a culturally equivalent version of the Prosthesis Evaluation Questionnaire in the Spanish language. Cross-cultural questionnaire validation. Two-step process for cultural adaptation: forward and backward translations of English original and Spanish translated versions; assessment of both construct and criterion validity and reliability in a group of vascular amputees. A total of 61 patients were recruited, 44 men (72.1%) and 17 women (27.9%), with a median age of 71.1 years (standard deviation: 7.7 years; range: 51-87 years). In the Prosthesis Evaluation Questionnaire-Spanish, the lowest scores were for gait and frustration, and the highest scores were for noise and stump health. Internal consistency of the questionnaire was acceptable (>0.70) for four of the scales used in the Prosthesis Evaluation Questionnaire but poor (<0.50) for the scales relating to appearance and stump health. Correlations with the quality-of-life levels as measured by the Short Form-36 were positive and mostly significant. Prosthesis Evaluation Questionnaire-Spanish could assess the quality of life in patients who have undergone vascular amputations and then been fitted with a prosthetic limb. The questionnaire shows adequate criteria validity when compared with other instruments for measuring quality of life. The Prosthesis Evaluation Questionnaire-Spanish could be a valid and reliable instrument for assessing adaptation to prostheses in vascular amputees. The questionnaire adds information relevant to the patient and the physician and may identify cases with poor expected adaptation to the prosthesis. © The International Society for Prosthetics and Orthotics 2015.
Resident career planning needs in internal medicine: a qualitative assessment.
Garcia, Rina L; Windish, Donna M; Rosenbaum, Julie R
2010-12-01
Few residency programs have centralized resources for career planning. As a consequence, little is known about residents' informational needs regarding career planning. To examine career preparation stressors, practical needs, and information that residents wished they were privy to when applying. In 2007 and 2008, we surveyed 163 recent graduates or graduating residents from 10 Yale-based and Yale-affiliated hospitals' internal medicine programs regarding their experiences with applying for positions after residency. We included questions about demographics, mentorship, stress of finding a job or fellowship, and open-ended questions to assess barriers and frustrations. Qualitative data were coded independently and a classification scheme was negotiated by consensus. A total of 89 residents or recent graduates responded, and 75% of them found career planning during residency training at least somewhat stressful. Themes regarding the application process included (1) knowledge about the process, (2) knowledge about career paths and opportunities, (3) time factors, (4) importance of adequate personal guidance and mentorship, and (5) self-knowledge regarding priorities and the desired outcome. Residents identified the following advice as most important: (1) start the process as early as possible and with a clear knowledge of the process timeline, (2) be clear about personal goals and priorities, and (3) be well-informed about a prospective employer and what that employer is looking for. Most residents felt career planning should be structured into the curriculum and should occur in the first year or throughout residency. This study highlights residents' desire for structured dissemination of information and counseling with regard to career planning during residency. Our data suggest that exposure to such resources may be beneficial as early as the first year of training.
Resident Career Planning Needs in Internal Medicine: A Qualitative Assessment
Garcia, Rina L.; Windish, Donna M.; Rosenbaum, Julie R.
2010-01-01
Background Few residency programs have centralized resources for career planning. As a consequence, little is known about residents' informational needs regarding career planning. Objective To examine career preparation stressors, practical needs, and information that residents wished they were privy to when applying. Methods In 2007 and 2008, we surveyed 163 recent graduates or graduating residents from 10 Yale-based and Yale-affiliated hospitals' internal medicine programs regarding their experiences with applying for positions after residency. We included questions about demographics, mentorship, stress of finding a job or fellowship, and open-ended questions to assess barriers and frustrations. Qualitative data were coded independently and a classification scheme was negotiated by consensus. Results A total of 89 residents or recent graduates responded, and 75% of them found career planning during residency training at least somewhat stressful. Themes regarding the application process included (1) knowledge about the process, (2) knowledge about career paths and opportunities, (3) time factors, (4) importance of adequate personal guidance and mentorship, and (5) self-knowledge regarding priorities and the desired outcome. Residents identified the following advice as most important: (1) start the process as early as possible and with a clear knowledge of the process timeline, (2) be clear about personal goals and priorities, and (3) be well-informed about a prospective employer and what that employer is looking for. Most residents felt career planning should be structured into the curriculum and should occur in the first year or throughout residency. Conclusions This study highlights residents' desire for structured dissemination of information and counseling with regard to career planning during residency. Our data suggest that exposure to such resources may be beneficial as early as the first year of training. PMID:22132271
Effects of frustration on explosive synchronization
NASA Astrophysics Data System (ADS)
Huang, Xia; Gao, Jian; Sun, Yu-Ting; Zheng, Zhi-Gang; Xu, Can
2016-12-01
In this study, we consider the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be correlated with their degrees and frustration is included in the system. This assumption can enhance or delay the explosive transition to synchronization. Interestingly, a de-synchronization phenomenon occurs and the type of phase transition is also changed. Furthermore, we provide an analytical treatment based on a star graph, which resembles that obtained in scale-free networks. Finally, a self-consistent approach is implemented to study the de-synchronization regime. Our findings have important implications for controlling synchronization in complex networks because frustration is a controllable parameter in experiments and a discontinuous abrupt phase transition is always dangerous in engineering in the real world.
Updating the phase diagram of the archetypal frustrated magnet Gd3Ga5O12
NASA Astrophysics Data System (ADS)
Deen, P. P.; Florea, O.; Lhotel, E.; Jacobsen, H.
2015-01-01
The applied magnetic field and temperature phase diagram of the archetypal frustrated magnet, Gd3Ga5O12 , has been reinvestigated using single-crystal magnetometry and polarized neutron diffraction. The updated phase diagram is substantially more complicated than previously reported and can be understood in terms of competing interactions with loops of spins, trimers, and decagons, in addition to competition and interplay between antiferromagnetic, incommensurate, and ferromagnetic order. Several additional distinct phase boundaries are presented. The phase diagram centers around a multiphase convergence to a single point at 0.9 T and ˜0.35 K, below which, in temperature, a very narrow magnetically disordered region exists. These data illustrate the richness and diversity that arise from frustrated exchange on the three-dimensional hyperkagome lattice.
Solution to the sign problem in a frustrated quantum impurity model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hann, Connor T., E-mail: connor.hann@yale.edu; Huffman, Emilie; Chandrasekharan, Shailesh
2017-01-15
In this work we solve the sign problem of a frustrated quantum impurity model consisting of three quantum spin-half chains interacting through an anti-ferromagnetic Heisenberg interaction at one end. We first map the model into a repulsive Hubbard model of spin-half fermions hopping on three independent one dimensional chains that interact through a triangular hopping at one end. We then convert the fermion model into an inhomogeneous one dimensional model and express the partition function as a weighted sum over fermion worldline configurations. By imposing a pairing of fermion worldlines in half the space we show that all negative weightmore » configurations can be eliminated. This pairing naturally leads to the original frustrated quantum spin model at half filling and thus solves its sign problem.« less
Structurally frustrated relaxor ferroelectric behavior in CaCu{sub 3}Ti{sub 4}O{sub 12}
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu Yun; Withers, Ray L.; Wei Xiaoyong
2005-10-01
Direct diffraction evidence for structurally frustrated relaxor ferroelectric behavior in the form of one-dimensionally correlated, off-center displacements of Ti ions within the TiO{sub 6} octahedra of CaCu{sub 3}Ti{sub 4}O{sub 12} (CCTO) has been obtained. When coupled with the observation of a ferroelectric effect, important implications for the understanding of the extraordinary dielectric properties of CCTO arise. That the incipient ferroelectric behavior is correlated only along one-dimensional <001> columns of TiO{sub 6} octahedra in the absence of an applied electric field offers a crucial insight into the underlying nature of CCTO and suggests the existence of a unique class of structurallymore » frustrated, ferroelectric relaxors.« less
Quantum Monte Carlo Simulation of Frustrated Kondo Lattice Models
NASA Astrophysics Data System (ADS)
Sato, Toshihiro; Assaad, Fakher F.; Grover, Tarun
2018-03-01
The absence of the negative sign problem in quantum Monte Carlo simulations of spin and fermion systems has different origins. World-line based algorithms for spins require positivity of matrix elements whereas auxiliary field approaches for fermions depend on symmetries such as particle-hole symmetry. For negative-sign-free spin and fermionic systems, we show that one can formulate a negative-sign-free auxiliary field quantum Monte Carlo algorithm that allows Kondo coupling of fermions with the spins. Using this general approach, we study a half-filled Kondo lattice model on the honeycomb lattice with geometric frustration. In addition to the conventional Kondo insulator and antiferromagnetically ordered phases, we find a partial Kondo screened state where spins are selectively screened so as to alleviate frustration, and the lattice rotation symmetry is broken nematically.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Furukawa, Yuji
This paper presents a comprehensive review of nuclear magnetic resonance (NMR) studies performed on three nanoscale molecular magnets with different novel configurations of geometrically frustrated antiferromagnetic (AFM) triangles: (1) the isolated single AFM triangle K 6[V 15As 6O 42(H 2O)]·8H 2O (in short V15), (2) the spin ball [Mo 72Fe 30O 252(Mo 2O 7(H 2O)) 2(Mo 2O 8H 2(H 2O)) (CH 3COO) 12(H 2O) 91]·150H 2O (in short Fe30 spin ball), and (3) the twisted triangular spin tube [(CuCl 2tachH) 3Cl]Cl 2 (in short Cu3 spin tube). In V15t, from 51V NMR spectra, the local spin configurations were directly determinedmore » in both the nonfrustrated total spin S T = 3/2 state at higher magnetic fields (H ge; 2.7 T) and the two nearly degenerate S T = 1/2 ground states at lower magnetic fields (H ≤ 2.7 T). The dynamical magnetic properties of V15 were investigated by proton spin-lattice relaxation rate (1/T 1) measurements. In the S T = 3/2 state, 1/T 1 shows thermally activated behaviour as a function of temperature. On the other hand, the temperature independent behaviour of 1/T 1 at very low temperatures is observed in the frustrated S T = 1/2 ground state. Possible origins for the peculiar behaviour of 1/T 1 will be discussed in terms of magnetic fluctuations due to spin frustrations. In Fe30, static and dynamical properties of Fe 3+ (s = 5/2) have been investigated by proton NMR spectra and 1/T 1 measurements. From the temperature dependence of 1/T 1, the fluctuation frequency of the Fe 3+ spins is found to decrease with decreasing temperature, indicating spin freezing at low temperatures. The spin freezing is also evidenced by the observation of a sudden broadening of 1H NMR spectra below 0.6 K. Finally, 1H NMR data in Cu3 will be described. An observation of magnetic broadening of 1H NMR spectra at low temperatures below 1 K directly revealed a gapless ground state. The 1/T 1 measurements revealed a usual slow spin dynamics in the Cu3 spin tube.« less
Furukawa, Yuji
2016-10-01
This paper presents a comprehensive review of nuclear magnetic resonance (NMR) studies performed on three nanoscale molecular magnets with different novel configurations of geometrically frustrated antiferromagnetic (AFM) triangles: (1) the isolated single AFM triangle K 6[V 15As 6O 42(H 2O)]·8H 2O (in short V15), (2) the spin ball [Mo 72Fe 30O 252(Mo 2O 7(H 2O)) 2(Mo 2O 8H 2(H 2O)) (CH 3COO) 12(H 2O) 91]·150H 2O (in short Fe30 spin ball), and (3) the twisted triangular spin tube [(CuCl 2tachH) 3Cl]Cl 2 (in short Cu3 spin tube). In V15t, from 51V NMR spectra, the local spin configurations were directly determinedmore » in both the nonfrustrated total spin S T = 3/2 state at higher magnetic fields (H ge; 2.7 T) and the two nearly degenerate S T = 1/2 ground states at lower magnetic fields (H ≤ 2.7 T). The dynamical magnetic properties of V15 were investigated by proton spin-lattice relaxation rate (1/T 1) measurements. In the S T = 3/2 state, 1/T 1 shows thermally activated behaviour as a function of temperature. On the other hand, the temperature independent behaviour of 1/T 1 at very low temperatures is observed in the frustrated S T = 1/2 ground state. Possible origins for the peculiar behaviour of 1/T 1 will be discussed in terms of magnetic fluctuations due to spin frustrations. In Fe30, static and dynamical properties of Fe 3+ (s = 5/2) have been investigated by proton NMR spectra and 1/T 1 measurements. From the temperature dependence of 1/T 1, the fluctuation frequency of the Fe 3+ spins is found to decrease with decreasing temperature, indicating spin freezing at low temperatures. The spin freezing is also evidenced by the observation of a sudden broadening of 1H NMR spectra below 0.6 K. Finally, 1H NMR data in Cu3 will be described. An observation of magnetic broadening of 1H NMR spectra at low temperatures below 1 K directly revealed a gapless ground state. The 1/T 1 measurements revealed a usual slow spin dynamics in the Cu3 spin tube.« less
ERIC Educational Resources Information Center
Michael-Luna, Sara
2013-01-01
While the population of bilinguals and English learners continues to rise in our schools, teachers often feel frustrated with their lack of knowledge about best practices to support their multilingual students' language, socio-emotional and cognitive development. Teachers' frustration is compounded by the push for assessments in the…
Understanding Children's Anger: Recognizing and Working with Young Children's Anger and Frustration
ERIC Educational Resources Information Center
Honig, Alice Sterling; Miller, Susan A.; Church, Ellen Booth
2007-01-01
This article presents the causes of anger and frustrations of children at different ages. Honig discusses understanding children's anger from ages 0-2 and gives suggestions on how to cope with anger. Miller discusses how children ages 3-4 provoke to anger, and recommends ways to prevent it. Church discusses the cause of anger in 5- and 6-year old…
Expertise on Cognitive Workloads and Performance During Navigation and Target Detection
2012-03-01
requiring little or no attention 1. Little confusion, risk, frustration, or anxiety exists and can be easily accomodated 2. Occasionally have spare...to confusion, frustration, or anxiety noticeably adds to workload. Significant compensation is required to maintain adequate performance. 3... anxiety . High to extreme determination and self- control required 59 Field Description elapsedTime (sec) Continuous measurement of time from the
ERIC Educational Resources Information Center
Goldsborough, Harriett; And Others
Many urban high school principals are finding their jobs increasingly demanding and frustrating. This report, the result of a CEA questionnaire survey, summarizes the views of 190 principals in 23 cities on how they view their role and responsibilities. The main point of frustration is felt to be the apparent erosion of their function as…
ERIC Educational Resources Information Center
Kolodinsky, Pit; Draves, Patrick; Schroder, Vincent; Lindsey, Charles; Zlatev, Michael
2009-01-01
A survey was designed to comprehensively assess multiple aspects of school counselor job satisfaction and job-related frustration, as well as orientation with the comprehensive curriculum-based guidance program used in Arizona. The five-page survey was completed by 155 Arizona school counselors. While the majority of respondents reported high…
ERIC Educational Resources Information Center
Forehand, Rex; Long, Nicholas
Parenting is one the most difficult tasks that adults face, and parenting strong-willed children can be even more difficult and frustrating. Parents of strong-willed children are often frustrated by their children's behavior as well as the lack of support and resources to help them deal with their children. This book describes a self-guided…
Tjin A Tsoi, Sharon L N M; de Boer, Anthonius; Croiset, Gerda; Koster, Andries S; van der Burgt, Stéphanie; Kusurkar, Rashmi A
2018-01-31
Insufficient professional development may lead to poor performance of healthcare professionals. Therefore, continuing education (CE) and continuing professional development (CPD) are needed to secure safe and good quality healthcare. The aim of the study was to investigate the hypothesized associations and their directions between pharmacists' basic psychological needs in CE, their academic motivation, well-being, learning outcomes. Self-determination theory was used as a theoretical framework for this study. Data were collected through four questionnaires measuring: academic motivation, basic psychological needs (BPN), vitality and lifelong learning adaptability of pharmacists in the CE/CPD learning context. Structural equation modelling was used to analyze the data. Demographic factors like gender and working environment influenced the observed scores for frustration of BPN and factors like training status and working experience influenced the observed scores for academic motivation. A good model fit could be found only for a part of the hypothesized pathway. Frustration of BPN is positively directly related to the less desirable type of academic motivation, controlled motivation (0.88) and negatively directly related to vitality (- 1.61) and negatively indirectly related to learning outcomes in CE. Fulfillment or frustration of BPN are important predictors for well-being and learning outcomes. Further research should be conducted to discover how we can prevent these needs from being frustrated in order to design a motivating, vitalizing and sustainable CE/CPD system for pharmacists and other healthcare professionals. Basic psychological needs are very important predictors for well-being and learning outcomes. Further research should be conducted to discover how we can prevent these needs from being frustrated in order to design a motivating, vitalizing and sustainable CE/CPD system for pharmacists and other healthcare professionals.
Boiling regimes of impacting drops on a heated substrate under reduced pressure
NASA Astrophysics Data System (ADS)
van Limbeek, Michiel A. J.; Hoefnagels, Paul B. J.; Shirota, Minori; Sun, Chao; Lohse, Detlef
2018-05-01
We experimentally investigate the boiling behavior of impacting ethanol drops on a heated smooth sapphire substrate at pressures ranging from P =0.13 bar to atmospheric pressure. We employ frustrated total internal reflection imaging to study the wetting dynamics of the contact between the drop and the substrate. The spreading drop can be in full contact (contact boiling), it can partially touch (transition boiling), or the drop can be fully levitated (Leidenfrost boiling). We show that the temperature of the boundary between contact and transition boiling shows at most a weak dependence on the impact velocity, but a significant decrease with decreasing ambient gas pressure. A striking correspondence is found between the temperature of this boundary and the static Leidenfrost temperature for all pressures. We therefore conclude that both phenomena share the same mechanism and are dominated by the dynamics taking place at the contact line. On the other hand, the boundary between transition boiling and Leidenfrost boiling, i.e., the dynamic Leidenfrost temperature, increases for increasing impact velocity for all ambient gas pressures. Moreover, the dynamic Leidenfrost temperature coincides for pressures between P =0.13 and 0.54 bar, whereas for atmospheric pressure the dynamic Leidenfrost temperature is slightly elevated. This indicates that the dynamic Leidenfrost temperature is at most weakly dependent on the enhanced evaporation by the lower saturation temperature of the liquid.
Active integrated filters for RF-photonic channelizers.
El Nagdi, Amr; Liu, Ke; LaFave, Tim P; Hunt, Louis R; Ramakrishna, Viswanath; Dabkowski, Mieczyslaw; MacFarlane, Duncan L; Christensen, Marc P
2011-01-01
A theoretical study of RF-photonic channelizers using four architectures formed by active integrated filters with tunable gains is presented. The integrated filters are enabled by two- and four-port nano-photonic couplers (NPCs). Lossless and three individual manufacturing cases with high transmission, high reflection, and symmetric couplers are assumed in the work. NPCs behavior is dependent upon the phenomenon of frustrated total internal reflection. Experimentally, photonic channelizers are fabricated in one single semiconductor chip on multi-quantum well epitaxial InP wafers using conventional microelectronics processing techniques. A state space modeling approach is used to derive the transfer functions and analyze the stability of these filters. The ability of adapting using the gains is demonstrated. Our simulation results indicate that the characteristic bandpass and notch filter responses of each structure are the basis of channelizer architectures, and optical gain may be used to adjust filter parameters to obtain a desired frequency magnitude response, especially in the range of 1-5 GHz for the chip with a coupler separation of ∼9 mm. Preliminarily, the measurement of spectral response shows enhancement of quality factor by using higher optical gains. The present compact active filters on an InP-based integrated photonic circuit hold the potential for a variety of channelizer applications. Compared to a pure RF channelizer, photonic channelizers may perform both channelization and down-conversion in an optical domain.
From frustration to coping with caring for death by nurse technicians.
Beraldo, Lívia Maria; de Almeida, Débora Vieira; Bocchi, Silvia Cristina Mangini
2015-01-01
to understand nurse technicians' experience with caring for the death of terminal patients in ICUs and to configure a theoretical model. qualitative study with theoretical saturation when analyzing the 10th non-directive interview, having as reference Grounded Theory, Symbolic Interactionism and Bioethics. the core category - from frustration to coping with dignified nursing care for finitude: the acceptance of death as a therapeutic and intervenient component - emerged from the comparison of the sub-processes: when the nurse does not feel prepared for caring for death, accepting death as a therapeutic phenomenon and developing coping strategies. according to Symbolic Interactionism, a novice professional's frustration in caring for an individual for death is related to his/her interaction and interpretation of the situation as he/she feels prepared only to care for individuals for life.
Frustrated Freedom: The Effects of Agency and Wealth on Wellbeing in Rural Mozambique.
Victor, Bart; Fischer, Edward; Cooil, Bruce; Vergara, Alfredo; Mukolo, Abraham; Blevins, Meridith
2013-07-01
In Sen's capability view of poverty, wellbeing is threatened by both deficits of wealth and deficits of individual agency. Sen further predicts that "unfreedom," or low levels of agency will suppress the wellbeing effects of higher levels of wealth. The current paper extends Sen's view to include a condition, labeled "frustrated freedom," in which relatively higher levels of agency can heighten the poverty effects of relatively low levels of material wealth. Applying data from a large scale population study of female heads of household in rural Mozambique, the paper empirically tests Sen's view and the proposed extension. As predicted, agency is found to moderate the relationship between agency, wealth, and wellbeing, uncovering evidence of both unfreedom and frustrated freedom in the population. Further research into the complex dynamics of wellbeing and poverty are called for by the authors.
Rumsey, Michele; Thiessen, Jodi; Buchan, James; Daly, John
2016-02-01
To discuss the perceptions about the International English Language Testing System (IELTS) and its impact on migration and practice of migrant health professionals in Australia. Thematic analysis of interviews with 14 health industry participants and 35 migrated health professionals in Australia. Language testing is a barrier to health professional registration for migrant health workers in Australia. While two English language tests are recognised by the registration authorities in Australia, it is the International English Language Testing System that is most commonly used. This paper reports that study participants had underlying negative perceptions of the International English Language Testing System which they report, affect their move to Australia. These negative perceptions are caused by: frustration due to changes to processes for migration and registration; challenges regarding the structure of IELTS including timing of when test results expire, scoring requirements, cost, and suitability; and the resulting feelings of inadequacy caused by the test itself. This study has shown that some respondents have experienced difficulties in relation to the International English Language Testing System as part of their migration process. It was found that there is very little research into the effectiveness of the IELTS as it is currently administered for overseas health care professionals. Several recommendations are provided including areas for further research. Copyright © 2015 Elsevier Ltd. All rights reserved.
KITAE I: Edge Organisation in Battlespace Helmand
2011-06-01
military organization with its own culture that frustrates the timely delivery of complete information to the authority with assets to take synchronized...21st century information technologies, we have a 19th century military organization with its own culture that frustrates the timely delivery of...Table 5.0 QEQ NOV Table 6.0 QEQ DEC Table 7.0 QEQ JAN 4 Asymmetric warfare is a confrontation between political, cultural , social and
Lin, Yi-Ching; Latner, Janet D; Fung, Xavier C C; Lin, Chung-Ying
2018-02-01
To examine the associations between body image (actual and self-perceived weight status; feelings about appearance) and health outcomes (overall health, life satisfaction, and mental health) and between body image and experiences of being bullied. Participants included 8,303 children from 7th to 10th grade in the Health Behavior of School-Aged Children (HBSC) 2009-2010 data set, a large-scale sample in the United States. Several multiple linear regressions (with health outcomes as dependent variables) and multivariate logistic regressions (with being bullied or not as dependent variable) were conducted to investigate the associations between each dependent variable and the following independent variables: relationship with parents, frustration with appearance, and actual and self-perceived weight status. Self-perceived underweight, self-perceived overweight (OW), and frustration with appearance were positively associated with being bullied. Frustration with appearance was a risk factor, while good relationship with parents was a protective factor, especially for psychological health outcomes. Self-perceived OW had a stronger association with the experience of being bullied than actual OW. The relationship between actual OW and being bullied might be attenuated when self-perceived OW is simultaneously considered. Body image may be an important factor in the association between weight status and the experience of being bullied. © 2017 The Obesity Society.
Delmonico, R L; Hanley-Peterson, P; Englander, J
1998-12-01
Residual emotional and behavioral difficulties in individuals who have sustained a traumatic brain injury (TBI) have been well documented in the literature. The issues are complex, interdependent, and often include substance abuse, depression, anxiety, chronic suicidal or homicidal ideation, poor impulse control, and significant degrees of frustration and anger. Often, preexisting psychological conditions and poor coping strategies are exacerbated by the trauma. Emotional and behavioral difficulties can interfere with the neurorehabilitation process at all levels. In acute rehabilitation, these issues have traditionally been addressed on an individual basis. However, in postacute settings, an interpersonal group format can be effectively implemented. The majority of individuals with TBI have minimal funding for long-term cognitive and behavioral remediation; often the only avenue available is support groups. This article will describe group psychotherapy models used with individuals with acute or postacute TBI within a comprehensive rehabilitation center. Interdisciplinary treatment of frustration and substance abuse and a continuum of care will be emphasized. Education, social support, skills development, interpersonal process, and cognitive-behavioral approaches will also be discussed. The psychotherapy groups focus on treatment of substance abuse and frustration management through education, social support, and development of interpersonal skills. Practical considerations of running such groups are presented.
Antiferromagnetism, structural instability and frustration in intermetallic AFe4X2 systems
NASA Astrophysics Data System (ADS)
Rosner, Helge; Bergmann, Christoph; Weber, Katharina; Kraft, Inga; Mufti, N.; Klauss, Hans-Henning; Dellmann, T.; Woike, T.; Geibel, Christoph
2013-03-01
Magnetic systems with reduced dimensionality or frustration attract strong interest because these features lead to an increase of quantum fluctuations and often result in unusual properties. Here, we present a detailed study of the magnetic, thermodynamic, and structural properties of the intermetallic AFe4X2 compounds (A=Sc,Y,Lu,Zr; X=Si,Ge) crystallizing in the ZrFe4Si2 structure type. Our results evidence that these compounds cover the whole regime from frustrated AFM order up to an AFM quantum critical point. Susceptibility χ(T), specific heat, resistivity, and T-dependent XRD measurements were performed on polycrystalline samples. In all compounds we observed a Curie-Weiss behavior in χ(T) at high T indicating a paramagnetic moment of about 3μB/Fe. Magnetic and structural transitions as previously reported for YFe4Ge2 occur in all compounds with trivalent A. However, transition temperatures, nature of the transition as well as the relation between structural and magnetic transitions change significantly with the A element. Low TN's and large θCW /TN ratios confirm the relevance of frustration. The results are analyzed and discussed with respect to electronic, structural and magnetic instabilities applying DFT calculations. Financial support from the DFG (GRK 1621) is acknowledged
Kögerler, Paul; Tsukerblat, Boris; Müller, Achim
2010-01-07
The structural versatility characterizing polyoxometalate chemistry, in combination with the option to deliberately use well-defined building blocks, serves as the foundation for the generation of a large family of magnetic clusters, frequently comprising highly symmetric spin arrays. If the spin centers are coupled by antiferromagnetic exchange, some of these systems exhibit spin frustration, which can result in novel magnetic properties of purely molecular origins. We discuss here the magnetic properties of selected nanosized polyoxometalate clusters featuring spin triangles as their magnetic 'building blocks' or fragments. This includes unique porous Keplerate clusters of the type {(Mo)Mo(5)}(12)M(30) (M = Fe(III), Cr(III), V(IV)) with the spin centers defining a regular icosidodecahedron and the {V(15)As(6)}-type cluster sphere containing a single equilateral spin triangle; these species are widely discussed and studied in the literature for their role in materials science as molecular representations of Kagomé lattices and in relation to quantum computing, respectively. Exhibiting fascinating and unique structural features, these magnetic molecules allow the study of the implications of frustrated spin ordering. Furthermore, this perspective covers the impact of spin frustration on the degeneracy of the ground state and related problems, namely strong magnetic anisotropy and the interplay of antisymmetric exchange and structural Jahn-Teller effects.
The past 10 years of gastroenterology and hepatology-reflections and predictions.
Friedman, Scott L; Quigley, Eamonn M M; Sharkey, Keith A; Sung, Joseph J Y; Whitcomb, David C
2014-11-01
In November 2004, the very first issue of this journal featured articles on the pathogenesis of ulcerative colitis, mechanisms leading to chronic pancreatitis, and treatment of recurrent Clostridium-difficile-associated diarrhoea. Although those topics might seem familiar, much has changed in the intervening years in our understanding, diagnosis and treatment of many different diseases across the field of gastroenterology and hepatology. Nonetheless, many challenges remain. Here, we have asked five of our Advisory Board members-international experts across different subspecialties in gastroenterology and hepatology-to reflect on the progress and frustrations of the past 10 years. They also comment on where effort and money should be invested now, as well as their predictions for progress in the next 10 years.
Harland, Nicholas; Drew, Benjamin T
2013-09-01
The purpose of this study was to discover the frequency and type of use of online resources for continuing professional development displayed by physiotherapists in the UK. Therapists' skills, needs and frustrations using these resources were explored. With the relatively recent release and saturated use of the internet the potential presence of a skills gap between therapists at different stages of their career was also investigated. National online survey study. The online survey was carried out using the international online service 'Survey Monkey'. 774 physiotherapists from students to band 8c completed the survey. The online survey was advertised through Frontline, the Interactive Chartered Society of Physiotherapy, Journal of Physiotherapy Pain Association and cascade email through research and other networks. Most physiotherapists reported using the internet for professional purposes daily (40%) or 2 to 4 times a week (37%), with only 8% of respondents using it less than once a week. Overall the results suggest band 6 and 7 physiotherapists had the least skills and most frustrations when using online search engines. History and the nature of rapid technological advancement, specifically of the internet, appears to have created a generational skills gap within the largest group of the physiotherapy workforce band 6 and 7 therapists. Students, band 5 and band 8a therapists appear to most successfully use online resources and the reasons for this are explored. Copyright © 2012 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
Runnels, Vivien; Turner, Leigh
2011-01-01
Health-related travel, also referred to as "medical tourism" is historically well-known. Its emerging contemporary form suggests the development of a form of globalised for-profit healthcare. Medical tourism to India, the focus of a recent conference in Canada, provides an example of the globalisation of healthcare. By positioning itself as a low-cost, high-tech, fast-access and high-quality healthcare destination country, India offers healthcare to medical travellers who are frustrated with waiting lists and the limited availability of some procedures in Canada. Although patients have the right to travel and seek care at international medical facilities, there are a number of dimensions of medical tourism that are disturbing. The diversion of public investments in healthcare to the private sector, in order to serve medical travellers, perversely transfers public resources to international patients at a time when the Indian public healthcare system fails to provide primary healthcare to its own citizens. Further, little is known about patient safety and quality care in transnational medical travel. Countries that are departure points as well as destination countries need to carefully explore the ethical, social, cultural, and economic consequences of the growing phenomenon of for-profit international medical travel.
NASA Astrophysics Data System (ADS)
Hayton, D. J.; Jenkins, T. E.
2004-02-01
The effects of back-surface reflection from transparent substrates on ellipsometric measurements are discussed and it is shown that their effects can be minimized by placing the substrate on a commercially available product, Blu-tack. The ellipsometric properties of Blu-tack in the range 250 850 nm are presented and the frustration of the back-surface reflection is discussed in terms of index matching between substrate and Blu-tack.
NASA Astrophysics Data System (ADS)
Jurčišinová, E.; Jurčišin, M.
2018-04-01
Anomalies of the specific heat capacity are investigated in the framework of the exactly solvable antiferromagnetic spin- 1 / 2 Ising model in the external magnetic field on the geometrically frustrated tetrahedron recursive lattice. It is shown that the Schottky-type anomaly in the behavior of the specific heat capacity is related to the existence of unique highly macroscopically degenerated single-point ground states which are formed on the borders between neighboring plateau-like ground states. It is also shown that the very existence of these single-point ground states with large residual entropies predicts the appearance of another anomaly in the behavior of the specific heat capacity for low temperatures, namely, the field-induced double-peak structure, which exists, and should be observed experimentally, along with the Schottky-type anomaly in various frustrated magnetic system.
Creation of Frustrated Systems by d-dot Array
NASA Astrophysics Data System (ADS)
Masahiko, Machida
2004-03-01
When a square shape dot of High-Tc superconductor is embedded in s-wave superconducting matrix, half quantized vortices are spontaneously generated at the corners of the dot. This feature gives the magnetic interactions between neighboring dots in array systems composed of sevaral dots of High-Tc superconductor and allows us to make magnetic interaction systems. We propose that we can create interesting frustrated systems like the spin-ice by setting the dots in various manners. In order to demonstrate which types of frustrated systems are possible, we perform numerical simulations for the time-dependent Ginzburg-Landau equation describing dynamics of the superconducting order parameters with d-wave and s-wave symmetries. The simulations reveal that the proposed system has two parameters originated from the magnetic interaction between emerged half vortices. We tune the parameters and show various patterns of half vortices from the Ising to the ice model.
Morphological Consequences of Frustration in ABC Triblock Polymers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Radlauer, Madalyn R.; Sinturel, Christophe; Asai, Yusuke
2016-12-19
Three poly(styrene)-block-poly(isoprene)-block-poly(lactide) (PS-b-PI-b-PLA, SIL) triblock terpolymers were synthesized and characterized in the bulk and as thin films. The pronounced incompatibility of the covalently connected PI and PLA led to significant frustration and the tendency to minimize their intermaterial dividing surface area. This resulted in the formation of a core–shell cylinder morphology with exaggerated nonconstant mean curvature from triblock polymers with equal block volume fractions rather than the more typical lamellar morphology. The effect of frustration was magnified in thin films by both confinement and interfacial interactions such that the PI domains became discontinuous. Self-consistent field theory (SCFT) calculations emphasize thatmore » the marked difference in the PS/PI and PI/PLA interaction parameters promotes the formation of nonlamellar morphologies. However, SCFT predicts that lamellar morphology is more stable than the observed cylindrical morphology, demonstrating a limitation that arises from the underlying assumptions.« less
Chen, Hsiu-fen
2011-01-01
This article argues that early Chinese physicians had already related female ailments to their sexual frustration. Moreover, many physicians paid more attention to non-reproductive women – nuns, widows, and unmarried women – as if they were more prone to suffer from unfulfilled desires and sexual frustration and, as a result, produce the sexual dreams and monstrous births that were described in the medical literature of medieval China as physical ailments. The earlier body-oriented etiology of these female illnesses gradually shifted to emotion-oriented perspectives in late imperial China. In particular, the sixteenth- and seventeenth-century doctors began to categorize women's sexual frustration as "yu disorders" or "love madness." In this article I will show not only the changing medical views of female sexual madness throughout the ages, but how these views were shaped by the societies in which both the doctors and patients were situated.
Correlated states in β-Li 2IrO 3 driven by applied magnetic fields
Ruiz, Alejandro; Frano, Alex; Breznay, Nicholas P.; ...
2017-10-16
Magnetic honeycomb iridates are thought to show strongly spin-anisotropic exchange interactions which, when highly frustrated, lead to an exotic state of matter known as the Kitaev quantum spin liquid. However, in all known examples these materials magnetically order at finite temperatures, the scale of which may imply weak frustration. Here we show that the application of a relatively small magnetic field drives the three-dimensional magnet β-Li 2IrO 3 from its incommensurate ground state into a quantum correlated paramagnet. Interestingly, this paramagnetic state admixes a zig-zag spin mode analogous to the zig-zag order seen in other Mott-Kitaev compounds. The rapid onsetmore » of the field-induced correlated state implies the exchange interactions are delicately balanced, leading to strong frustration and a near degeneracy of different ground states.« less
Frustration across the periodic table: heterolytic cleavage of dihydrogen by metal complexes.
Bullock, R Morris; Chambers, Geoffrey M
2017-08-28
This perspective examines frustrated Lewis pairs (FLPs) in the context of heterolytic cleavage of H 2 by transition metal complexes, with an emphasis on molecular complexes bearing an intramolecular Lewis base. FLPs have traditionally been associated with main group compounds, yet many reactions of transition metal complexes support a broader classification of FLPs that includes certain types of transition metal complexes with reactivity resembling main group-based FLPs. This article surveys transition metal complexes that heterolytically cleave H 2 , which vary in the degree that the Lewis pairs within these systems interact. Many of the examples include complexes bearing a pendant amine functioning as the base with the metal functioning as the hydride acceptor. Consideration of transition metal compounds in the context of FLPs can inspire new innovations and improvements in transition metal catalysis.This article is part of the themed issue 'Frustrated Lewis pair chemistry'. © 2017 The Author(s).
Health Care Provider Burnout in a United States Military Medical Center During a Period of War.
Sargent, Paul; Millegan, Jeffrey; Delaney, Eileen; Roesch, Scott; Sanders, Martha; Mak, Heather; Mallahan, Leonard; Raducha, Stephanie; Webb-Murphy, Jennifer
2016-02-01
Provider burnout can impact efficiency, empathy, and medical errors. Our study examines burnout in a military medical center during a period of war. A survey including the Maslach Burnout Inventory (MBI), deployment history, and work variables was distributed to health care providers. MBI subscale means were calculated and associations between variables were analyzed. Approximately 60% of 523 respondents were active duty and 34% had deployed. MBI subscale means were 19.99 emotional exhaustion, 4.84 depersonalization, and 40.56 personal accomplishment. Frustration over administrative support was associated with high emotional exhaustion and depersonalization; frustration over life/work balance was associated with high emotional exhaustion. Levels of burnout in our sample were similar to civilian medical centers. Sources of frustration were related to administrative support and life/work balance. Deployment had no effect on burnout levels. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.
NASA Astrophysics Data System (ADS)
Sim, Hasung; Lee, Seongsu; Hong, Kun-Pyo; Jeong, Jaehong; Zhang, J. R.; Kamiyama, T.; Adroja, D. T.; Murray, C. A.; Thompson, S. P.; Iga, F.; Ji, S.; Khomskii, D.; Park, Je-Geun
2016-11-01
Dy B4 has a two-dimensional Shastry-Sutherland (Sh-S) lattice with strong Ising character of the Dy ions. Despite the intrinsic frustrations, it undergoes two successive transitions: a magnetic ordering at TN=20 K and a quadrupole ordering at TQ=12.5 K . From high-resolution neutron and synchrotron x-ray powder diffraction studies, we have obtained full structural information on this material in all phases and demonstrate that structural modifications occurring at quadrupolar transition lead to the lifting of frustrations inherent in the Sh-S model. Our paper thus provides a complete experimental picture of how the intrinsic frustration of the Sh-S lattice can be lifted by the coupling to quadrupole moments. We show that two other factors, i.e., strong spin-orbit coupling and long-range Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in metallic Dy B4 , play an important role in this behavior.
Frustration and thermalization in an artificial magnetic quasicrystal
NASA Astrophysics Data System (ADS)
Shi, Dong; Budrikis, Zoe; Stein, Aaron; Morley, Sophie A.; Olmsted, Peter D.; Burnell, Gavin; Marrows, Christopher H.
2018-03-01
Artificial frustrated systems offer a playground to study the emergent properties of interacting systems. Most work to date has been on spatially periodic systems, known as artificial spin ices when the interacting elements are magnetic. Here we have studied artificial magnetic quasicrystals based on quasiperiodic Penrose tiling patterns of interacting nanomagnets. We construct a low-energy configuration from a step-by-step approach that we propose as a ground state. Topologically induced emergent frustration means that this configuration cannot be constructed from vertices in their ground states. It has two parts, a quasi-one-dimensional `skeleton' that spans the entire pattern and is capable of long-range order, surrounding `flippable' clusters of macrospins that lead to macroscopic degeneracy. Magnetic force microscopy imaging of Penrose tiling arrays revealed superdomains that are larger for more strongly coupled arrays, especially after annealing the array above its blocking temperature.
Minamoto, Takehiro; Osaka, Mariko; Yaoi, Ken; Osaka, Naoyuki
2014-01-01
Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation.
Frustration and thermalization in an artificial magnetic quasicrystal
Shi, Dong; Budrikis, Zoe; Stein, Aaron; ...
2017-12-11
Here, artificial frustrated systems offer a playground to study the emergent properties of interacting systems. Most work to date has been on spatially periodic systems, known as artificial spin ices when the interacting elements are magnetic. Here we have studied artificial magnetic quasicrystals based on quasiperiodic Penrose tiling patterns of interacting nanomagnets. We construct a low-energy configuration from a step-by-step approach that we propose as a ground state. Topologically induced emergent frustration means that this configuration cannot be constructed from vertices in their ground states. It has two parts, a quasi-one-dimensional ‘skeleton’ that spans the entire pattern and is capablemore » of long-range order, surrounding ‘flippable’ clusters of macrospins that lead to macroscopic degeneracy. Magnetic force microscopy imaging of Penrose tiling arrays revealed superdomains that are larger for more strongly coupled arrays, especially after annealing the array above its blocking temperature.« less
Frustrated Freedom: The Effects of Agency and Wealth on Wellbeing in Rural Mozambique
Victor, Bart; Fischer, Edward; Cooil, Bruce; Vergara, Alfredo; Mukolo, Abraham; Blevins, Meridith
2014-01-01
In Sen's capability view of poverty, wellbeing is threatened by both deficits of wealth and deficits of individual agency. Sen further predicts that “unfreedom,” or low levels of agency will suppress the wellbeing effects of higher levels of wealth. The current paper extends Sen's view to include a condition, labeled “frustrated freedom,” in which relatively higher levels of agency can heighten the poverty effects of relatively low levels of material wealth. Applying data from a large scale population study of female heads of household in rural Mozambique, the paper empirically tests Sen's view and the proposed extension. As predicted, agency is found to moderate the relationship between agency, wealth, and wellbeing, uncovering evidence of both unfreedom and frustrated freedom in the population. Further research into the complex dynamics of wellbeing and poverty are called for by the authors. PMID:25125791
NASA Astrophysics Data System (ADS)
Ren, Y.; Ye, F.; Huang, Q.; Fernandez-Baca, J. A.; Dai, Pengcheng; Lynn, J. W.; Kimura, T.
2006-03-01
We use high resolution synchrotron X-ray and neutron diffraction to study the geometrically frustrated triangular lattice antiferromagnet (TLA) CuFeO2. We show that the occurrence of the two magnetic transitions, at 14 K and 11 K, respectively is accompanied simultaneously by a second-and first- order structural phase transitions from a hexagonal structure to a monoclinic form. This is the first observation of two successive spin-driven structural transitions directly coupled with incommensurate and commensurate magnetic orderings in frustrated TLA systems. This work is supported by the U. S. NSF DMR-0453804 and DOE Nos. DE-FG02-05ER46202 and DE-AC05-00OR22725 with UT/Battelle LLC. Use of the Advanced Photon Source was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. W-31-109-Eng-38.
Gilbert, Ian; Nisoli, Cristiano; Schiffer, Peter
2016-07-01
Geometrical frustration is a condition that occurs when a material’s lattice geometry precludes minimizing the energy of all the interactions among pairs of neighbors simultaneously. Moreover, the simplest example is three antiferromagnetically coupled Ising spins, pointing up or down, on the corners of an equilateral triangle: It is also impossible to arrange the spins so that each pair is antiparallel. In more complex magnetic lattices, the frustrated state can arise from the combination of lattice geometry and the strength and sign of the interactions among the magnetic dipole moments.1 (See the article by Roderich Moessner and Art Ramirez, Physics Today,more » February 2006, page 24.) A wide variety of exotic and collective phenomena sometimes arises from the competing interactions. One prime example is spin liquids, materials in which the local atomic moments fluctuate down to the lowest accessible temperatures and never settle into a static ground-state configuration.« less
Frustration and thermalization in an artificial magnetic quasicrystal
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, Dong; Budrikis, Zoe; Stein, Aaron
Here, artificial frustrated systems offer a playground to study the emergent properties of interacting systems. Most work to date has been on spatially periodic systems, known as artificial spin ices when the interacting elements are magnetic. Here we have studied artificial magnetic quasicrystals based on quasiperiodic Penrose tiling patterns of interacting nanomagnets. We construct a low-energy configuration from a step-by-step approach that we propose as a ground state. Topologically induced emergent frustration means that this configuration cannot be constructed from vertices in their ground states. It has two parts, a quasi-one-dimensional ‘skeleton’ that spans the entire pattern and is capablemore » of long-range order, surrounding ‘flippable’ clusters of macrospins that lead to macroscopic degeneracy. Magnetic force microscopy imaging of Penrose tiling arrays revealed superdomains that are larger for more strongly coupled arrays, especially after annealing the array above its blocking temperature.« less
Relationship between mental workload and musculoskeletal disorders among Alzahra Hospital nurses
Habibi, Ehsanollah; Taheri, Mohamad Reza; Hasanzadeh, Akbar
2015-01-01
Background: Musculoskeletal disorders (MSDs) are a serious problem among the nursing staff. Mental workload is the major cause of MSDs among nursing staff. The aim of this study was to investigate the mental workload dimensions and their association with MSDs among nurses of Alzahra Hospital, affiliated to Isfahan University of Medical Sciences. Materials and Methods: This descriptive cross-sectional study was conducted on 247 randomly selected nurses who worked in the Alzahra Hospital in Isfahan, Iran in the summer of 2013. The Persian version of National Aeronautics and Space Administration Task Load Index (NASA-TLX) (measuring mental load) specialized questionnaire and Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) was used for data collection. Data were collected and analyzed by Pearson correlation coefficient and Spearman correlation coefficient tests in SPSS 20. Results: Pearson and Spearman correlation tests showed a significant association between the nurses’ MSDs and the dimensions of workload frustration, total workload, temporal demand, effort, and physical demand (r = 0.304, 0.277, 0.277, 0.216, and 0.211, respectively). However, there was no significant association between the nurses’ MSDs and the dimensions of workload performance and mental demand (P > 0.05). Conclusions: The nurses’ frustration had a direct correlation with MSDs. This shows that stress is an inseparable component in hospital workplace. Thus, reduction of stress in nursing workplace should be one of the main priorities of hospital managers. PMID:25709683
Mechanics and geometry in the seashell-like (Turritella) surface
NASA Astrophysics Data System (ADS)
Guo, Qiaohang; Chen, Zi; Li, Wei; Ren, Kun; Lin, Junjie; Taber, Larry A.; Chen, Wenzhe
2013-03-01
Helical structures are ubiquitous in nature and engineering, ranging from DNA molecules to plant tendrils, from sea snail shells to nanoribbons. While the helical shapes in natural and engineered systems often exhibit nearly uniform radius and pitch, helical shell structures with changing radius and pitch, such as seashells and some plant tendrils, adds to the variety of this family of aesthetic beauty. Here we report the first biomimetic seashell-like structure resulting from mechanics of geometric frustration. In previous studies, the total potential energy is everywhere minimized when the system achieves an equilibrium. In this study, however, the local energy minimization cannot be realized because of the geometric incompatibility, and hence the whole system deforms into a shape with a global energy minimum whereby the energy in each segment may not necessary be locally optimized. This novel approach can be applied to develop materials and systems with desirable geometries by exploiting mechanics of geometric frustration. The authors would like to thank Yushan Huang, Zhen Liu, Si Chen for their assistance in the experimental demonstration. This work has been in part supported by NSFC (Grant No.11102040 and No.11201001044), the Sigma Xi Grants-in-Aid of Research (GIAR) program, American Academy of Mechanics Founder's Award from the Robert M. and Mary Haythornthwaite Foundation, and Society in Science, The Branco Weiss Fellowship, administered by ETH Zurich. Qiaohang Guo and Zi Chen contributed equally to this work.
Diagnosis and treatment of academic frustration syndrome.
Grover, P L; Tessier, K E
1978-09-01
A random sample of medical students was compared with others who were unable to cope with unanticipated academic frustration. The noncoping students demonstrated higher levels of debilitating anxiety and lower levels of facilitating anxiety while their perceptions of locus of control tended to be more extreme. No difference was found in study habits and attitudes. Techniques of attribution therapy and desensitization in the counseling of these students proved to be effective in improving coping behavior in six of seven cases.
NASA Astrophysics Data System (ADS)
Bramwell, Steven T.; Gingras, Michel J. P.; Holdsworth, Peter C. W.
2013-03-01
Pauling's model of hydrogen disorder in water ice represents the prototype of a frustrated system. Over the years it has spawned several analogous models, including Anderson's model antiferromagnet and the statistical "vertex" models. Spin Ice is a sixteen vertex model of "ferromagnetic frustration" that is approximated by real materials, most notably the rare earth pyrochlores Ho2Ti2O7, Dy2Ti2O7 and Ho2Sn2O7. These "spin ice materials" have the Pauling zero point entropy and in all respects represent almost ideal realisations of Pauling's model. They provide experimentalists with unprecedented access to a wide variety of novel magnetic states and phase transitions that are located in different regions of the field-temperature phase diagram. They afford theoreticians the opportunity to explore many new features of the magnetic interactions and statistical mechanics of frustrated systems. This chapter is a comprehensive review of the physics -- both experimental and theoretical -- of spin ice. It starts with a discussion of the historic problem of water ice and its relation to spin ice and other frustrated magnets. The properties of spin ice are then discussed in three sections that deal with the zero field spin ice state, the numerous field-induced states (including the recently identified "kagomé ice") and the magnetic dynamics. Some materials related to spin ice are briefly described and the chapter is concluded with a short summary of spin ice physics.
Evidence for the principle of minimal frustration in the evolution of protein folding landscapes.
Tzul, Franco O; Vasilchuk, Daniel; Makhatadze, George I
2017-02-28
Theoretical and experimental studies have firmly established that protein folding can be described by a funneled energy landscape. This funneled energy landscape is the result of foldable protein sequences evolving following the principle of minimal frustration, which allows proteins to rapidly fold to their native biologically functional conformations. For a protein family with a given functional fold, the principle of minimal frustration suggests that, independent of sequence, all proteins within this family should fold with similar rates. However, depending on the optimal living temperature of the organism, proteins also need to modulate their thermodynamic stability. Consequently, the difference in thermodynamic stability should be primarily caused by differences in the unfolding rates. To test this hypothesis experimentally, we performed comprehensive thermodynamic and kinetic analyses of 15 different proteins from the thioredoxin family. Eight of these thioredoxins were extant proteins from psychrophilic, mesophilic, or thermophilic organisms. The other seven protein sequences were obtained using ancestral sequence reconstruction and can be dated back over 4 billion years. We found that all studied proteins fold with very similar rates but unfold with rates that differ up to three orders of magnitude. The unfolding rates correlate well with the thermodynamic stability of the proteins. Moreover, proteins that unfold slower are more resistant to proteolysis. These results provide direct experimental support to the principle of minimal frustration hypothesis.
Work intensity in sacroiliac joint fusion and lumbar microdiscectomy
Frank, Clay; Kondrashov, Dimitriy; Meyer, S Craig; Dix, Gary; Lorio, Morgan; Kovalsky, Don; Cher, Daniel
2016-01-01
Background The evidence base supporting minimally invasive sacroiliac (SI) joint fusion (SIJF) surgery is increasing. The work relative value units (RVUs) associated with minimally invasive SIJF are seemingly low. To date, only one published study describes the relative work intensity associated with minimally invasive SIJF. No study has compared work intensity vs other commonly performed spine surgery procedures. Methods Charts of 192 patients at five sites who underwent either minimally invasive SIJF (American Medical Association [AMA] CPT® code 27279) or lumbar microdiscectomy (AMA CPT® code 63030) were reviewed. Abstracted were preoperative times associated with diagnosis and patient care, intraoperative parameters including operating room (OR) in/out times and procedure start/stop times, and postoperative care requirements. Additionally, using a visual analog scale, surgeons estimated the intensity of intraoperative care, including mental, temporal, and physical demands and effort and frustration. Work was defined as operative time multiplied by task intensity. Results Patients who underwent minimally invasive SIJF were more likely female. Mean procedure times were lower in SIJF by about 27.8 minutes (P<0.0001) and mean total OR times were lower by 27.9 minutes (P<0.0001), but there was substantial overlap across procedures. Mean preservice and post-service total labor times were longer in minimally invasive SIJF (preservice times longer by 63.5 minutes [P<0.0001] and post-service labor times longer by 20.2 minutes [P<0.0001]). The number of postoperative visits was higher in minimally invasive SIJF. Mean total service time (preoperative + OR time + postoperative) was higher in the minimally invasive SIJF group (261.5 vs 211.9 minutes, P<0.0001). Intraoperative intensity levels were higher for mental, physical, effort, and frustration domains (P<0.0001 each). After taking into account intensity, intraoperative workloads showed substantial overlap. Conclusion Compared to a commonly performed lumbar spine surgical procedure, lumbar microdiscectomy, that currently has a higher work RVU, preoperative, intraoperative, and postoperative workload for minimally invasive SIJF is higher. The work RVU for minimally invasive SIJF should be adjusted upward as the relative amount of work is comparable. PMID:27555790
Micioni Di Bonaventura, Maria Vittoria; Ciccocioppo, Roberto; Romano, Adele; Bossert, Jennifer M.; Rice, Kenner C.; Ubaldi, Massimo; St. Laurent, Robyn; Gaetani, Silvana; Massi, Maurizio; Shaham, Yavin
2014-01-01
We developed recently a binge-eating model in which female rats with a history of intermittent food restriction show binge-like palatable food consumption after 15 min exposure to the sight of the palatable food. This “frustration stress” manipulation also activates the hypothalamic–pituitary–adrenal stress axis. Here, we determined the role of the stress neurohormone corticotropin-releasing factor (CRF) in stress-induced binge eating in our model. We also assessed the role of CRF receptors in the bed nucleus of the stria terminalis (BNST), a brain region implicated in stress responses and stress-induced drug seeking, in stress-induced binge eating. We used four groups that were first exposed or not exposed to repeated intermittent cycles of regular chow food restriction during which they were also given intermittent access to high-caloric palatable food. On the test day, we either exposed or did not expose the rats to the sight of the palatable food for 15 min (frustration stress) before assessing food consumption for 2 h. We found that systemic injections of the CRF1 receptor antagonist R121919 (2,5-dimethyl-3-(6-dimethyl-4-methylpyridin-3-yl)-7 dipropylamino pyrazolo[1,5-a]pyrimidine) (10–20 mg/kg) and BNST (25–50 ng/side) or ventricular (1000 ng) injections of the nonselective CRF receptor antagonist d-Phe-CRF(12–41) decreased frustration stress-induced binge eating in rats with a history of food restriction. Frustration stress also increased Fos (a neuronal activity marker) expression in ventral and dorsal BNST. Results demonstrate a critical role of CRF receptors in BNST in stress-induced binge eating in our rat model. CRF1 receptor antagonists may represent a novel pharmacological treatment for bingeing-related eating disorders. PMID:25143612
Micioni Di Bonaventura, Maria Vittoria; Ciccocioppo, Roberto; Romano, Adele; Bossert, Jennifer M; Rice, Kenner C; Ubaldi, Massimo; St Laurent, Robyn; Gaetani, Silvana; Massi, Maurizio; Shaham, Yavin; Cifani, Carlo
2014-08-20
We developed recently a binge-eating model in which female rats with a history of intermittent food restriction show binge-like palatable food consumption after 15 min exposure to the sight of the palatable food. This "frustration stress" manipulation also activates the hypothalamic-pituitary-adrenal stress axis. Here, we determined the role of the stress neurohormone corticotropin-releasing factor (CRF) in stress-induced binge eating in our model. We also assessed the role of CRF receptors in the bed nucleus of the stria terminalis (BNST), a brain region implicated in stress responses and stress-induced drug seeking, in stress-induced binge eating. We used four groups that were first exposed or not exposed to repeated intermittent cycles of regular chow food restriction during which they were also given intermittent access to high-caloric palatable food. On the test day, we either exposed or did not expose the rats to the sight of the palatable food for 15 min (frustration stress) before assessing food consumption for 2 h. We found that systemic injections of the CRF1 receptor antagonist R121919 (2,5-dimethyl-3-(6-dimethyl-4-methylpyridin-3-yl)-7 dipropylamino pyrazolo[1,5-a]pyrimidine) (10-20 mg/kg) and BNST (25-50 ng/side) or ventricular (1000 ng) injections of the nonselective CRF receptor antagonist D-Phe-CRF(12-41) decreased frustration stress-induced binge eating in rats with a history of food restriction. Frustration stress also increased Fos (a neuronal activity marker) expression in ventral and dorsal BNST. Results demonstrate a critical role of CRF receptors in BNST in stress-induced binge eating in our rat model. CRF1 receptor antagonists may represent a novel pharmacological treatment for bingeing-related eating disorders. Copyright © 2014 the authors 0270-6474/14/3411316-09$15.00/0.
Milestones in the History of Ear Reconstruction.
Berghaus, Alexander; Nicoló, Marion San
2015-12-01
The reconstruction of ear deformities has been challenging plastic surgeons since centuries. However, it is only in the 19th century that reports on partial and total ear reconstruction start increasing. In the quest for an aesthetically pleasing and natural-looking result, surgeons worked on the perfect framework and skin coverage. Different materials and flap techniques have evolved. Some were abandoned out of frustration, while others kept evolving over the years. In this article, we discuss the milestones in ear reconstruction-from ancient times to early attempts in Western civilization to the key chapters of ear reconstruction in the 20th century leading to the current techniques. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Emergence and Frustration of Magnetism with Variable-Range Interactions in a Quantum Simulator
2013-05-03
quantum entanglement . Here, we engineer frustrated antiferromagnetic interactions between spins stored in a crystal of up to 16 trapped 171Yb+ atoms. We...individual trapped ion spins (10–14) and the observation of spin frus- tration and quantum entanglement in the smallest system of three spins (15). Here...monroe@umd.edu www.sciencemag.org SCIENCE VOL 340 3 MAY 2013 583 and the excitation gap (Fig. 1A) closes, leading to a finite entropy density in the
Energy landscape in frustrated systems: Cation hopping in pyrochlores
NASA Astrophysics Data System (ADS)
Brooks Hinojosa, Beverly; Asthagiri, Aravind; Nino, Juan C.
2013-07-01
We investigate the dynamics of the local environment and electronic structure in inherently dipolar frustrated pyrochlore compounds to help identify the fundamental nature of dipolar disorder in pyrochlore systems and determine the necessary and sufficient conditions for dielectric relaxation. We map out the energy landscape associated with cation hopping events in three compounds and correlate the hopping pathway with experimental dielectric response. Comprehensive analysis of the calculations allows us to postulate rules to predict the occurrence of relaxation and cation hopping pathways.
Cancer-related terminology: glossaries for compounded pharmacists and their clients.
Williams, Lavonn A
2008-01-01
Webster's dictionary defines cancer as a "pernicious, spreading evil...", a definition that is hard to debate. Cancer is a life-changing disease for both the patient with cancer and the family members. Compounding pharmacists have the resources to assist patients in reducing their pain, nausea, and other symptoms of cancer and the side effects of their cancer treatments. By providing a glossary of terms for clients affected by cancer, compounding pharmacists also can reduce at least a small part of their frustration. The International Journal of Pharmaceutical Compounding, Inc., has published many formulations and articles dealing with cancer-related symptoms and treatment side effects, and is working hard to get more formulations online so we can participate in the challenge and victory of defeating the pain and suffering of patients with cancer.
Hinnant, J. Benjamin; EL-Sheikh, Mona
2013-01-01
We investigated the roles of sex and respiratory sinus arrhythmia (RSA), an index of autonomic parasympathetic nervous system activity, as predictors of codeveloping externalizing and internalizing symptoms in middle childhood. We expected that sex, baseline RSA (RSA-B), and RSA reactivity (RSA-R) to two types of tasks would interact to differentiate co-occurring trajectories of symptoms. We tested these hypotheses by combining longitudinal data from two independent samples (n = 390; 210 girls, 180 boys) with repeated measures at ages 8, 9, 10, and 11. RSA-R was measured in response to a socially stressful and frustrating stressor. Indicators of growth in externalizing and internalizing symptoms were derived from multiple domain growth models and used in person-centered growth mixture analyses. Three groups of externalizing and internalizing trajectories were found. Profile membership was predicted by several two-way interactions among sex, RSA-B, or RSA-R but was not predicted by three-way interactions. Children with low RSA-B and strong RSA withdrawal, girls with low RSA-B, and girls with strong RSA withdrawal were more likely to be on a developmental trajectory of low externalizing symptoms and moderately elevated internalizing symptoms. Membership in the high externalizing and high internalizing trajectory was predicted by weak RSA withdrawal for boys and strong RSA withdrawal for girls. The type of stressor task also played a role in predicting probability of profile membership. Results are discussed in the context of developmental psychobiology and implications for the codevelopment of psychopathology symptoms in childhood. PMID:23627954
Polyhedra and packings from hyperbolic honeycombs.
Pedersen, Martin Cramer; Hyde, Stephen T
2018-06-20
We derive more than 80 embeddings of 2D hyperbolic honeycombs in Euclidean 3 space, forming 3-periodic infinite polyhedra with cubic symmetry. All embeddings are "minimally frustrated," formed by removing just enough isometries of the (regular, but unphysical) 2D hyperbolic honeycombs [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] to allow embeddings in Euclidean 3 space. Nearly all of these triangulated "simplicial polyhedra" have symmetrically identical vertices, and most are chiral. The most symmetric examples include 10 infinite "deltahedra," with equilateral triangular faces, 6 of which were previously unknown and some of which can be described as packings of Platonic deltahedra. We describe also related cubic crystalline packings of equal hyperbolic discs in 3 space that are frustrated analogues of optimally dense hyperbolic disc packings. The 10-coordinated packings are the least "loosened" Euclidean embeddings, although frustration swells all of the hyperbolic disc packings to give less dense arrays than the flat penny-packing even though their unfrustrated analogues in [Formula: see text] are denser.
Static Holes in Geometrically Frustrated Bow Tie Ladder
NASA Astrophysics Data System (ADS)
Martins, George; Brenig, Wolfram
2007-03-01
Doping of the geometrically frustrated bow-tie spin ladder with static holes is investigated by a complementary approach using exact diagonalization and hard-core quantum dimers. Results for the thermodynamics in the undoped case, the singlet density of states, the hole-binding energy, and the spin correlations will be presented. We find that the static holes polarize their vicinity by a localization of singlets in order to reduce the frustration. As a consequence the singlet polarization cloud induces short range repulsive forces between the holes with oscillatory longer range behavior. For those systems we have studied, most results for the quantum dimer approach are found to be qualitatively if not quantitatively in agreement with exact diagonalization. The ground state of the undoped system is non-degenerate with translationally invariant nearest-neighbor spin correlations up to a few unit cells, which is consistent with a spin liquid state or a valence bond crystal with very large unit cell. C. Waldtmann, A. Kreutzmann, U. Schollwock, K. Maisinger, and H.-U. Everts, Phys. Rev. B 62, 9472 (2000).
Chen, Yuanping; Sun, Y Y; Wang, H; West, D; Xie, Yuee; Zhong, J; Meunier, V; Cohen, Marvin L; Zhang, S B
2014-08-22
A three-dimensional elemental carbon kagome lattice, made of only fourfold-coordinated carbon atoms, is proposed based on first-principles calculations. Despite the existence of 60° bond angles in the triangle rings, widely perceived to be energetically unfavorable, the carbon kagome lattice is found to display exceptional stability comparable to that of C(60). The system allows us to study the effects of triangular frustration on the electronic properties of realistic solids, and it demonstrates a metal-insulator transition from that of graphene to a direct gap semiconductor in the visible blue region. By minimizing s-p orbital hybridization, which is an intrinsic property of carbon, not only the band edge states become nearly purely frustrated p states, but also the band structure is qualitatively different from any known bulk elemental semiconductors. For example, the optical properties are similar to those of direct-gap semiconductors GaN and ZnO, whereas the effective masses are comparable to or smaller than those of Si.
Social Status and Anger Expression: The Cultural Moderation Hypothesis
Park, Jiyoung; Kitayama, Shinobu; Markus, Hazel R.; Coe, Christopher L.; Miyamoto, Yuri; Karasawa, Mayumi; Curhan, Katherine B.; Love, Gayle D.; Kawakami, Norito; Boylan, Jennifer Morozink; Ryff, Carol D.
2013-01-01
Individuals with lower social status have been reported to express more anger, but this evidence comes mostly from Western cultures. Here, we used representative samples of American and Japanese adults and tested the hypothesis that the association between social status and anger expression depends on whether anger serves primarily to vent frustration, as in the United States, or to display authority, as in Japan. Consistent with the assumption that lower social standing is associated with greater frustration stemming from life adversities and blocked goals, Americans with lower social status expressed more anger, with the relationship mediated by the extent of frustration. In contrast, consistent with the assumption that higher social standing affords a privilege to display anger, Japanese with higher social status expressed more anger, with the relationship mediated by decision-making authority. As expected, anger expression was predicted by subjective social status among Americans and by objective social status among Japanese. Implications for the dynamic construction of anger and anger expression are discussed. PMID:24098926
Social status and anger expression: the cultural moderation hypothesis.
Park, Jiyoung; Kitayama, Shinobu; Markus, Hazel R; Coe, Christopher L; Miyamoto, Yuri; Karasawa, Mayumi; Curhan, Katherine B; Love, Gayle D; Kawakami, Norito; Boylan, Jennifer Morozink; Ryff, Carol D
2013-12-01
Individuals with lower social status have been reported to express more anger, but this evidence comes mostly from Western cultures. Here, we used representative samples of American and Japanese adults and tested the hypothesis that the association between social status and anger expression depends on whether anger serves primarily to vent frustration, as in the United States, or to display authority, as in Japan. Consistent with the assumption that lower social standing is associated with greater frustration stemming from life adversities and blocked goals, Americans with lower social status expressed more anger, with the relationship mediated by the extent of frustration. In contrast, consistent with the assumption that higher social standing affords a privilege to display anger, Japanese with higher social status expressed more anger, with the relationship mediated by decision-making authority. As expected, anger expression was predicted by subjective social status among Americans and by objective social status among Japanese. Implications for the dynamic construction of anger and anger expression are discussed.
Linking psychological need experiences to daily and recurring dreams.
Weinstein, Netta; Campbell, Rachel; Vansteenkiste, Maarten
2018-01-01
The satisfaction of individuals' psychological needs for autonomy, competence, and relatedness, as conceived from a self-determination theory perspective, is said to be conducive to personal growth and well-being. What has been unexamined is whether psychological need-based experiences, either their satisfaction or frustration, manifests in people's self-reported dream themes as well as their emotional interpretation of their dreams. A cross-sectional study ( N = 200; M age = 21.09) focusing on individuals' recurrent dreams and a three-day diary study ( N = 110; M age = 25.09) focusing on daily dreams indicated that individuals experiencing psychological need frustration, either more enduringly or on a day-to-day basis, reported more negative dream themes and interpreted their dreams more negatively. The contribution of psychological need satisfaction was more modest, although it related to more positive interpretation of dreams. The discussion focuses on the role of dreams in the processing and integration of psychological need-frustrating experiences.
Magnetic order in a frustrated two-dimensional atom lattice at a semiconductor surface.
Li, Gang; Höpfner, Philipp; Schäfer, Jörg; Blumenstein, Christian; Meyer, Sebastian; Bostwick, Aaron; Rotenberg, Eli; Claessen, Ralph; Hanke, Werner
2013-01-01
Two-dimensional electron systems, as exploited for device applications, can lose their conducting properties because of local Coulomb repulsion, leading to a Mott-insulating state. In triangular geometries, any concomitant antiferromagnetic spin ordering can be prevented by geometric frustration, spurring speculations about 'melted' phases, known as spin liquid. Here we show that for a realization of a triangular electron system by epitaxial atom adsorption on a semiconductor, such spin disorder, however, does not appear. Our study compares the electron excitation spectra obtained from theoretical simulations of the correlated electron lattice with data from high-resolution photoemission. We find that an unusual row-wise antiferromagnetic spin alignment occurs that is reflected in the photoemission spectra as characteristic 'shadow bands' induced by the spin pattern. The magnetic order in a frustrated lattice of otherwise non-magnetic components emerges from longer-range electron hopping between the atoms. This finding can offer new ways of controlling magnetism on surfaces.
Yuan, Jiajin; Ding, Nanxiang; Liu, Yingying; Yang, Jiemin
2015-01-01
Reappraisal of negative events is known to be useful in decreasing their emotional impact. However, existent evidence for this conclusion mostly relies on conscious, deliberate reappraisal that comes with the cost of cognitive efforts. The aim of the present study was to compare emotion regulation effects of conscious and unconscious reappraisal, which has been shown to be less costly in previous studies. Subjects randomly assigned to an unconscious reappraisal, conscious reappraisal, and control condition performed a frustrating arithmetic task. Subjective emotional experience and heart-rate reactivity were recorded. Participants primed with unconscious reappraisal showed the same decrease in heart-rate reactivity as those explicitly instructed to reappraise. In addition, the unconscious reappraisal group did not show reductions in subjective negative emotion, whereas this was significantly decreased in the conscious reappraisal group. Heart-rate reactivity was positively correlated with negative emotion ratings and negatively correlated with the positive emotion ratings. These results suggest that unconscious reappraisal is only effective in decreasing physiological consequences of frustrating emotion, but not in reducing subjective experience.
Minamoto, Takehiro; Osaka, Mariko; Yaoi, Ken; Osaka, Naoyuki
2014-01-01
Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation. PMID:24454951
Emergent reduced dimensionality by vertex frustration in artificial spin ice
NASA Astrophysics Data System (ADS)
Gilbert, Ian; Lao, Yuyang; Carrasquillo, Isaac; O'Brien, Liam; Watts, Justin D.; Manno, Michael; Leighton, Chris; Scholl, Andreas; Nisoli, Cristiano; Schiffer, Peter
2016-02-01
Reducing the dimensionality of a physical system can have a profound effect on its properties, as in the ordering of low-dimensional magnetic materials, phonon dispersion in mercury chain salts, sliding phases, and the electronic states of graphene. Here we explore the emergence of quasi-one-dimensional behaviour in two-dimensional artificial spin ice, a class of lithographically fabricated nanomagnet arrays used to study geometrical frustration. We extend the implementation of artificial spin ice by fabricating a new array geometry, the so-called tetris lattice. We demonstrate that the ground state of the tetris lattice consists of alternating ordered and disordered bands of nanomagnetic moments. The disordered bands can be mapped onto an emergent thermal one-dimensional Ising model. Furthermore, we show that the level of degeneracy associated with these bands dictates the susceptibility of island moments to thermally induced reversals, thus establishing that vertex frustration can reduce the relevant dimensionality of physical behaviour in a magnetic system.
Acceleration through passive destabilization: protein folding in a weak hydrophobic environment
NASA Astrophysics Data System (ADS)
Jewett, Andrew; Baumketner, Andrij; Shea, Joan-Emma
2004-03-01
The GroEL chaperonin is a biomolecule which assists the folding of an extremely diverse range of proteins in Eubacteria. Some proteins undergo many rounds of ATP-regulated binding and dissociation from GroEL/ES before folding. It has been proposed that transient stress from ATP-regulated binding and release from GroEL/ES frees frustrated proteins from misfolded conformations. However recent evidence suggests that chaperonin-accelerated protein folding can take place entirely within a mutated GroEL+ES cavity that is unable to open and release the protein. Using molecular dynamics, we demonstrate that static confinement within a weakly hydrophobic (attractive) cavity (similar to the interior of the cavity formed by the GroEL+ES complex) is sufficient to significantly accelerate the folding of a highly frustrated protein-like heteropolymer. Our frustrated molecule benifits kinetically from a static hydrophobic environment that destabilizes misfolded conformations. This may shed light on the mechanisms used by other chaperones which do not depend on ATP.
Providers' perspectives on treating psychogenic nonepileptic seizures: frustration and hope.
McMillan, Katharine K; Pugh, Mary Jo; Hamid, Hamada; Salinsky, Martin; Pugh, Jacqueline; Noël, Polly H; Finley, Erin P; Leykum, Luci K; Lanham, Holly J; LaFrance, W Curt
2014-08-01
Recent diagnostic and treatment advances in psychogenic nonepileptic seizures (PNES) have the potential to improve care for patients, but little is known about the current state of PNES care delivery in the Veterans Health Administration (VA). We conducted semistructured interviews with 74 health-care clinicians and workers in the VA, eliciting provider perceptions of PNES care. Data were analyzed according to principles of Grounded Theory. The results revealed variation in care and two emergent domain themes of frustration and hope. Frustration was manifest in subthemes including Complexity, Patient Acceptance, Uncertainty About Treatment, Need for Evidence-based Treatment, and Failure of Cross-Disciplinary Collaboration between neurologists and mental health providers. Hope encompassed subthemes of Positive Attitudes, Developing Cross-Disciplinary Treatment, and Specific PNES Care. Increased resources for diagnosing, treating, and researching PNES have improved awareness of the disorder. More research is needed to understand patients' and caregivers' perceptions of PNES care. Copyright © 2014 Elsevier Inc. All rights reserved.
Claassen, Martin; Jiang, Hong -Chen; Moritz, Brian; ...
2017-10-30
The search for quantum spin liquids in frustrated quantum magnets recently has enjoyed a surge of interest, with various candidate materials under intense scrutiny. However, an experimental confirmation of a gapped topological spin liquid remains an open question. Here, we show that circularly polarized light can provide a knob to drive frustrated Mott insulators into a chiral spin liquid, realizing an elusive quantum spin liquid with topological order. We find that the dynamics of a driven Kagome Mott insulator is well-captured by an effective Floquet spin model, with heating strongly suppressed, inducing a scalar spin chirality S i · (Smore » j × S k) term which dynamically breaks time-reversal while preserving SU(2) spin symmetry. We fingerprint the transient phase diagram and find a stable photo-induced chiral spin liquid near the equilibrium state. Furthermore, the results presented suggest employing dynamical symmetry breaking to engineer quantum spin liquids and access elusive phase transitions that are not readily accessible in equilibrium.« less
Bidirectional Relations between Temperament and Parenting Styles in Chinese Children.
Lee, Erica H; Zhou, Qing; Eisenberg, Nancy; Wang, Yun
2013-01-01
The present study examined bidirectional relations between child temperament and parenting styles in a sample ( n = 425) of Chinese children during elementary school period (age range = 6 to 9 years at Wave 1). Using two waves (3.8 years apart) of longitudinal data, we tested two hypotheses: (1) whether child temperament (effortful control and anger/frustration) at Wave 1 predicts parenting styles (authoritative and authoritarian parenting) at Wave 2, controlling for Wave 1 parenting; and (2) whether parenting styles at Wave 1 predict Wave 2 temperament, controlling for Wave 1 temperament. We found support for bidirectional relations between temperament and authoritarian parenting, such that higher effortful control and lower anger/frustration were associated with higher authoritarian parenting across time and in both directions. There were no significant cross-time associations between children's temperament and authoritative parenting. These findings extend the previous tests of transactional relations between child temperament and parenting in Chinese children and are consistent with the cultural values toward effortful control and control of anger/frustration in Chinese society.
Emergent reduced dimensionality by vertex frustration in artificial spin ice
Gilbert, Ian; Lao, Yuyang; Carrasquillo, Isaac; ...
2015-10-26
Reducing the dimensionality of a physical system can have a profound effect on its properties, as in the ordering of low-dimensional magnetic materials, phonon dispersion in mercury chain salts, sliding phases, and the electronic states of graphene. Here we explore the emergence of quasi-one-dimensional behaviour in two-dimensional artificial spin ice, a class of lithographically fabricated nanomagnet arrays used to study geometrical frustration. We extend the implementation of artificial spin ice by fabricating a new array geometry, the so-called tetris lattice. We demonstrate that the ground state of the tetris lattice consists of alternating ordered and disordered bands of nanomagnetic moments.more » The disordered bands can be mapped onto an emergent thermal one-dimensional Ising model. Furthermore, we show that the level of degeneracy associated with these bands dictates the susceptibility of island moments to thermally induced reversals, thus establishing that vertex frustration can reduce the relevant dimensionality of physical behaviour in a magnetic system.« less
Teaching and assessing procedural skills: a qualitative study.
Touchie, Claire; Humphrey-Murto, Susan; Varpio, Lara
2013-05-14
Graduating Internal Medicine residents must possess sufficient skills to perform a variety of medical procedures. Little is known about resident experiences of acquiring procedural skills proficiency, of practicing these techniques, or of being assessed on their proficiency. The purpose of this study was to qualitatively investigate resident 1) experiences of the acquisition of procedural skills and 2) perceptions of procedural skills assessment methods available to them. Focus groups were conducted in the weeks following an assessment of procedural skills incorporated into an objective structured clinical examination (OSCE). Using fundamental qualitative description, emergent themes were identified and analyzed. Residents perceived procedural skills assessment on the OSCE as a useful formative tool for direct observation and immediate feedback. This positive reaction was regularly expressed in conjunction with a frustration with available assessment systems. Participants reported that proficiency was acquired through resident directed learning with no formal mechanism to ensure acquisition or maintenance of skills. The acquisition and assessment of procedural skills in Internal Medicine programs should move toward a more structured system of teaching, deliberate practice and objective assessment. We propose that directed, self-guided learning might meet these needs.
NASA Astrophysics Data System (ADS)
Ajeesh, M. O.; Yogi, A.; Padmanabhan, M.; Nath, R.
2015-04-01
Single crystalline and polycrystalline samples of S = 1 / 2 Kagomé lattices { [Cu3(CO3)2(bpe)3 ](CLO4)2 } n and { [Cu3(CO3)2(bpy)3 ](CLO4)2 } n, respectively were synthesized. Their structural and magnetic properties were characterized by means of x-ray diffraction and magnetization measurements. Both compounds crystalize in a hexagonal structure (space group P-6) consisting of CuO4 Kagomé layers in the ab-plane but linked along c direction through either rigid bpy or flexible bpe ligands to form 3D frame works. Magnetic measurements reveal that both the compounds undergo ferromagnetic ordering (TC) at low temperatures and the TC and the extent of frustration could be tuned by changing the nature of the pillar ligands. {[Cu3(CO3)2(bpe)3](CLO4)2}n which is made up of flexible bpe ligands has a TC of 5.7 K and a Curie-Weiss temperature (θCW) of -39.7 K giving rise to a frustration parameter of |θCW | /TC ≃ 6.96. But the replacement of bpe by a more rigid and electronically delocalized bpy ligand leads to an enhanced TC ≃ 9.3 K and a reduced frustration parameter of |θCW | /TC ≃ 3.54.
Disulfide Bridges: Bringing Together Frustrated Structure in a Bioactive Peptide.
Zhang, Yi; Schulten, Klaus; Gruebele, Martin; Bansal, Paramjit S; Wilson, David; Daly, Norelle L
2016-04-26
Disulfide bridges are commonly found covalent bonds that are usually believed to maintain structural stability of proteins. Here, we investigate the influence of disulfide bridges on protein dynamics through molecular dynamics simulations on the cysteine-rich trypsin inhibitor MCoTI-II with three disulfide bridges. Correlation analysis of the reduced cyclic peptide shows that two of the three disulfide distances (Cys(11)-Cys(23) and Cys(17)-Cys(29)) are anticorrelated within ∼1 μs of bridge formation or dissolution: when the peptide is in nativelike structures and one of the distances shortens to allow bond formation, the other tends to lengthen. Simulations over longer timescales, when the denatured state is less structured, do not show the anticorrelation. We propose that the native state contains structural elements that frustrate one another's folding, and that the two bridges are critical for snapping the frustrated native structure into place. In contrast, the Cys(4)-Cys(21) bridge is predicted to form together with either of the other two bridges. Indeed, experimental chromatography and nuclear magnetic resonance data show that an engineered peptide with the Cys(4)-Cys(21) bridge deleted can still fold into its near-native structure even in its noncyclic form, confirming the lesser role of the Cys(4)-Cys(21) bridge. The results highlight the importance of disulfide bridges in a small bioactive peptide to bring together frustrated structure in addition to maintaining protein structural stability. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Paul, Barnita; Chatterjee, Swastika; Roy, Anushree; Midya, A.; Mandal, P.; Grover, Vinita; Tyagi, A. K.
2017-02-01
In this article, we report negative thermal expansion and spin frustration in hexagonal GdInO3. Rietveld refinements of the x-ray diffraction patterns reveal that the negative thermal expansion in the temperature range of 50-100 K stems from the triangular lattice of Gd3 + ions. The downward deviation of the low-temperature inverse susceptibility (χ-1) versus T plot from the Curie-Weiss law and the large value of the ratio, | θCW|/ TN>28 , where θCW and TN are respectively Curie-Weiss and Neel temperature, indicate a strong spin frustration, which inhibits long-range magnetic ordering down to 1.8 K. Magnetostriction measurements clearly demonstrate a spin-lattice coupling in the system. Low-temperature anomalous phonon softening, as obtained from temperature-dependent Raman measurements, also reveals the same. Our experimental observations are supported by first-principles density functional theory calculations of the electronic and phonon dispersion in GdInO3. The calculations suggest that the GdInO3 lattice is highly frustrated at low temperature. Further, the calculated normal mode frequencies of the Gd-related Γ point phonon modes reveal significant magnetoelastic coupling in this system. The competitive role of magnetic interaction energy and thermal stabilization energy in determining the change in interatomic distances is the possible origin for the negative thermal expansion in GdInO3 over a limited range of temperature.
Delgado, Mikel M; Jacobs, Lucia F
2016-05-01
Under natural conditions, wild animals encounter situations where previously rewarded actions do not lead to reinforcement. In the laboratory, a surprising omission of reinforcement induces behavioral and emotional responses described as frustration. Frustration can lead to aggressive behaviors and to the persistence of noneffective responses, but it may also lead to new behavioral responses to a problem, a potential adaptation. We assessed the responses to inaccessible reinforcement in free-ranging fox squirrels (Sciurus niger). We trained squirrels to open a box to obtain food reinforcement, a piece of walnut. After 9 training trials, squirrels were tested in 1 of 4 conditions: a control condition with the expected reward, an alternative reinforcement (a piece of dried corn), an empty box, or a locked box. We measured the presence of signals suggesting arousal (e.g., tail flags and tail twitches) and found that squirrels performed fewer of these behaviors in the control condition and increased certain behaviors (tail flags, biting box) in the locked box condition, compared to other experimental conditions. When faced with nonreinforcement, that is, frustration, squirrels increased the number of interactions with the apparatus and spent more time interacting with the apparatus. This study of frustration responses in a free-ranging animal extends the conclusions of captive studies to the field and demonstrates that fox squirrels show short-term negatively valenced responses to the inaccessibility, omission, and change of reinforcement. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Measuring morale--does practice area deprivation affect doctors' well-being?
Grieve, S
1997-01-01
BACKGROUND: Morale is a perennial concern in general practice and, over the years, a variety of tools have been used to examine doctors' mental well-being in a range of psychological and sociological studies. Despite perceived associations between low morale and practice area deprivation, this has not been investigated previously. AIM: To devise and apply a measure of mental well-being in general practitioners, and to use this to investigate the effect of practice area deprivation. METHOD: A questionnaire was devised and piloted, then used in an anonymous postal survey of a random sample of 500 London general practitioners, with questions on demography, workload, practice characteristics, patient centredness, and practice area deprivation. RESULTS: A total of 334 (68%) doctors replied to the questionnaire. Of these, 45% often feel exhausted, 46% are often frustrated by trivial consultations, and a third are seriously disenchanted with work. The resulting well-being score had a normal distribution, was reproducible (test-retest reliability = 0.91), and was internally consistent (Cronbach's alpha = 0.76). Comments from respondents suggested good face validity. Low well-being was not associated with practice area deprivation, but was associated with time stress, small practices and primary care teams, and lack of patient centredness. CONCLUSION: The instrument provided a useful tool for examining doctors' well-being and the associations thereof. Well-being was not associated with practice area deprivation. Help for small primary care teams and measures to reduce time stress should help to improve morale. PMID:9406487
Qian, Jin; Shen, Mengmeng; Wang, Peifang; Wang, Chao; Li, Kun; Liu, Jingjing; Lu, Bianhe; Tian, Xin
2017-09-01
Powdered activated carbon (PAC), as an adsorbent, was applied to remove perfluorooctane sulfonate (PFOS) from aqueous solution. Laboratory batch experiments were performed to investigate the influences of phosphate (P) competition, temperature, and pH for PFOS adsorption onto PAC. The results showed that higher temperature favored PFOS adsorption in single and binary systems. The kinetic data fitted very well to the pseudo second-order kinetic model. Thermodynamically, the endothermic enthalpy of the PFOS adsorption in single and binary systems were 125.07 and 21.25 kJ mol -1 , respectively. The entropy of the PFOS adsorption in single and binary systems were 0.479 and 0.092 kJ mol -1 K -1 , respectively. And the Gibbs constants were negative. These results indicated that the adsorption processes were spontaneous. The adsorption isotherms of PFOS agreed well with the Langmuir model. In the single system, PFOS adsorption decreased with increased pH value. The difference in the amount of PFOS adsorption between the single and binary systems increased at higher pH. Frustrated total internal reflection (FTIR) demonstrated that P competition increased the hydrophilicity of the PAC and the electrostatic repulsion between PFOS and PAC, then the PFOS adsorption amount decreased. It also demonstrated that, at higher temperature, increased PFOS adsorption was mainly due to the higher diffusion rate of PFOS molecules and greater number of active sites opened on the PAC surface. Copyright © 2017 Elsevier Ltd. All rights reserved.
Derksen, Frans; Olde Hartman, Tim C; van Dijk, Annelies; Plouvier, Annette; Bensing, Jozien; Lagro-Janssen, Antoine
2017-05-01
There is general consensus that explicit expression of empathy in patient-GP communication is highly valued. Yet, little is known so far about patients' personal experiences with and expectations of empathy. Insight into these experiences and expectations can help to achieve more person-centeredness in GP practice care. Participants were recruited by a press report in local newspapers. adults, a visit to the GP in the previous year. Exclusion criterion: a formal complaint procedure. Five focus groups were conducted. The discussions were analyzed using constant comparative analysis. In total 28 participants took part in the focus group interviews. Three themes were identified: (1) Personalized care and enablement when empathy is present; (2) Frustrations when empathy is absent; (3) Potential pitfalls of empathy. Participants indicated that empathy helps build a more personal relationship and makes them feel welcome and at ease. Furthermore, empathy makes them feel supported and enabled. A lack of empathy can result in avoiding a visit to the GP. Empathy is perceived as an important attribute of patient-GP communication. Its presence results in feelings of satisfaction, relief and trust. Furthermore, it supports patients, resulting in new coping strategies. A lack of empathy causes feelings of frustration and disappointment and can lead to patients avoiding visiting their GP. More explicit attention should be given to empathy during medical education in general and during vocational GP-training. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Kim, Hyun-Sil; Kim, Hun-Soo
2008-12-01
The present study was aimed at determining the family factors related to juvenile delinquency and identifying the effect of family violence, family functioning, parental partner dynamics, and adolescents' personality on delinquent behavior among Korean adolescents. A cross-sectional study was performed using an anonymous, self-reporting questionnaire. The subjects for this study consisted of 1,943 Korean adolescents, including 1,236 students and 707 juvenile delinquents, using a proportional stratified random sampling method. Compared to student adolescents, delinquent adolescents perceived their parents as having a higher level of dysfunctional parental partner dynamics, poorer family functioning, and a higher level of family violence. Furthermore, delinquent adolescents were more likely to report a greater incidence of antisocial personality tendencies, a higher level of psychosomatic symptoms and frustration, and higher frequencies of delinquent behavior compared to student adolescents. Antisocial personality tendency and gender had the largest significant total effects on delinquent behavior, followed by family violence, psychosomatic symptoms, family functioning, parental partner dynamics and need frustration. On the other hand, family functioning and parental partner dynamics had the largest indirect effect on delinquent behavior. Gender, antisocial personality tendency, and family violence, in that order, had the largest direct effects on delinquent behavior. In conclusion, it is apparent from the results of the present study that delinquent Korean adolescents perceived and experienced significantly more family dysfunction, family violence, and poor parental partner dynamics than did non-delinquents.
NASA Astrophysics Data System (ADS)
Lymperakis, L.; Schulz, T.; Freysoldt, C.; Anikeeva, M.; Chen, Z.; Zheng, X.; Shen, B.; Chèze, C.; Siekacz, M.; Wang, X. Q.; Albrecht, M.; Neugebauer, J.
2018-01-01
Nominal InN monolayers grown by molecular beam epitaxy on GaN(0001) are investigated combining in situ reflection high-energy electron diffraction (RHEED), transmission electron microscopy (TEM), and density functional theory (DFT). TEM reveals a chemical intraplane ordering never observed before. Employing DFT, we identify a novel surface stabilization mechanism elastically frustrated rehybridization, which is responsible for the observed chemical ordering. The mechanism also sets an incorporation barrier for indium concentrations above 25% and thus fundamentally limits the indium content in coherently strained layers.
SPIN-FRUSTRATED EFFECT AND THE MAGNETIC PROPERTIES IN YMn1-xAlxO3
NASA Astrophysics Data System (ADS)
Zhang, A. M.; Zhu, W. H.; Wu, X. S.; Bian, Q.
2013-08-01
Polycrystalline samples YMn1-xAlxO3 with different Al doping concentration were synthesized by standard solid-state reaction. Effect of Al doping on the magnetic properties was studied. Magnetization measurements show that the magnetization increases, while the calculated frustration factor decreases with the doping content of Al3+ ion increasing. And the spin-glass behavior becomes more and more obvious with increasing the Al doping content. These results were ascribed to the broken exchange path between Mn ions by Al doping.
Punjani, Vidhika; Mohiuddin, Golam; Kaur, Supreet; Khan, Raj Kumar; Ghosh, Sharmistha; Pal, Santanu Kumar
2018-04-03
A new approach accompanied by superstructural frustration is reported. By attaching a cholesterol moiety directly to the central bent-core system it displayed exotic BPIII, BPII/I, Ncyb*, TGBA, SmAPA, SmA and SmX phases as shown by X-ray scattering results. While higher homologues of the series exhibited spontaneous formation of polar order (Ps ∼ 61 nC cm-2) upon applied voltage, the lower homologues showed thermochromic behaviour which can also be trapped via temperature quenching.
A new technique of laparoscopic cholangiography.
Hagan, K D; Rosemurgy, A S; Albrink, M H; Carey, L C
1992-04-01
With the advent and rapid proliferation of laparoscopic cholecystectomy, numerous techniques and "tips" have been described. Intraoperative cholangiography during laparoscopic cholecystectomy can be tedious, frustrating, and time consuming. Described herein is a technique of intraoperative cholangiography during laparoscopic cholecystectomy which has proven to be easy, fast, and succinct. This method utilizes a rigid cholangiogram catheter which is placed into the peritoneal cavity through a small additional puncture site. This catheter is easily inserted into the cystic duct by extracorporeal manipulation. We suggest this method to surgeons who have shared our prior frustration with intraoperative cholangiography.
Frustration and correlations in stacked triangular-lattice Ising antiferromagnets
NASA Astrophysics Data System (ADS)
Burnell, F. J.; Chalker, J. T.
2015-12-01
We study multilayer triangular-lattice Ising antiferromagnets with interlayer interactions that are weak and frustrated in an abc stacking. By analyzing a coupled height model description of these systems, we show that they exhibit a classical spin liquid regime at low temperature, in which both intralayer and interlayer correlations are strong but there is no long-range order. Diffuse scattering in this regime is concentrated on a helix in reciprocal space, as observed for charge ordering in the materials LuFe2O4 and YbFe2O4 .
Demaria, T P; Kassinove, H; Dill, C A
1989-01-01
A test consistency and confirmatory factor analyses were performed on the Survey of Personal Beliefs, a new measure of irrational thinking based on rational-emotive personality theory. The survey, which was logically derived, includes a general rationality factor and subscales measuring five hypothesized core categories of irrational beliefs. Subjects included a nonclinical sample of 130 men and 150 women, with a mean age of 46. Results indicated that the Survey of Personal Beliefs had satisfactory total and scale reliability. The confirmatory analyses supported a higher order factor model including 5 first-order factors ( awfulizing, self-directed shoulds, other-directed shoulds, low frustration tolerance, and self-worth) and 1 second-order or general factor.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Duffort, V.; Sarkar, T.; Caignaert, V., E-mail: vincent.caignaert@ensicaen.fr
2013-09-15
The possibility to lift the geometric frustration in the “114” stoichiomeric tetragonal oxide YBaFe{sub 4}O{sub 7.0} by decreasing the temperature has been investigated using neutron and synchrotron powder diffraction techniques. Besides the structural transition from tetragonal to monoclinic symmetry that appears at T{sub S}=180 K, a magnetic transition is observed below T{sub N}=95 K. The latter corresponds to a lifting of the 3D geometric frustration toward an antiferromagnetic long range ordering, never observed to date in a cubic based “114’” oxide. The magnetic structure, characterized by the propagation vector k{sub 1}=(0,0,½), shows that one iron Fe2 exhibits a larger magneticmore » moment than the three others, suggesting a possible charge ordering according to the formula YBaFe{sup 3+}Fe{sub 3}{sup 2+}O{sub 7.0}. The magnetic M(T) and χ′(T) curves, in agreement with neutron data, confirm the structural and magnetic transitions and evidence the coexistence of residual magnetic frustration. Moreover, the transport measurements show a resistive transition from a thermally activated conduction mechanism to a variable range hopping mechanism at T{sub S}=180 K, with a significant increase of the dependence of the resistivity vs. temperature. Mössbauer spectroscopy clearly evidences a change in the electronic configuration of the iron framework at the structural transition as well as coexistence of several oxidation states. The role of barium underbonding in these transitions is discussed. - Graphical abstract: Atomic displacements at the tetragonal-monoclinic transition in YBaFe{sub 4}O{sub 7}. Display Omitted - Highlights: • The structural and magnetic phase transitions of YBaFe{sub 4}O{sub 7} were studied below room temperature. • The tetragonal to monoclinic transition, characterized by NPD and SXRD, was studied using mode crystallography approach. • Monoclinic distortion allows the lifting of the geometrical frustration on the iron sublattice, leading to AF order at T=95 K.« less
Dauman, Nicolas; Erlandsson, Soly I.; Albarracin, Dolorès; Dauman, René
2017-01-01
Background: Qualitative research can help to improve the management of patients, meet their expectations and assist physicians in alleviating their suffering. The perception of moment-to-moment variability in tinnitus annoyance is an emerging field of exploration. This study sought to enlighten variability in tinnitus-induced disablement using a qualitative approach. Methods: Twelve participants (six females, six males, aged 51–79) were recruited via the French Tinnitus Association Journal for participation in recorded semi-structured interviews. Each participant had three interviews lasting 1 h, the sessions being separated one from the other by 2 weeks. Following recommendations of Charmaz (2014), the second and third interviews were aimed at gathering rich data, by enhancing the participants' reflexivity in the circumstances of distress caused by tinnitus. After transcription, the data (n = 36 interviews) were analyzed using the approach to Grounded Theory proposed by Strauss and Corbin (1998). Results: Tinnitus as persistent frustration emerged as being the core category uniting all the other categories of the study. Hence, the core category accounted for the broader scope in participants' experience of chronic tinnitus. It is suggested that tinnitus-induced disablement varied according to the degree of frustration felt by the participants in not being able to achieve their goals. The implications of this were analyzed using the following categories: “Losing body ownership,” “Lacking perspectives,” and “Persevering through difficulties.” Based on these findings, we draw a substantive theory of tinnitus tolerance that promotes an active, disciplined and individualized approach to tinnitus-induced disablement. The model distinguishes pathways from sustained suffering to reduced annoyance (i.e., emerging tolerance). It accounts for difficulties that the participants experienced with a perceived unchanged annoyance over time. Furthermore, this model identifies a set of new attitudes toward oneself and others that tinnitus tolerance would entail. Conclusion: The subjective experience of frustration enlightens tinnitus-induced disablement, offering new perspectives for long-term self-management. Modulation of frustration, rather than moderation of tinnitus interference, is suggested as a new approach to the clinical management of tinnitus-related distress. PMID:28848429
Quantum simulation of interacting spin models with trapped ions
NASA Astrophysics Data System (ADS)
Islam, Kazi Rajibul
The quantum simulation of complex many body systems holds promise for understanding the origin of emergent properties of strongly correlated systems, such as high-Tc superconductors and spin liquids. Cold atomic systems provide an almost ideal platform for quantum simulation due to their excellent quantum coherence, initialization and readout properties, and their ability to support several forms of interactions. In this thesis, I present experiments on the quantum simulation of long range Ising models in the presence of transverse magnetic fields with a chain of up to sixteen ultracold 171Yb+ ions trapped in a linear radio frequency Paul trap. Two hyperfine levels in each of the 171Yb+ ions serve as the spin-1/2 systems. We detect the spin states of the individual ions by observing state-dependent fluorescence with single site resolution, and can directly measure any possible spin correlation function. The spin-spin interactions are engineered by applying dipole forces from precisely tuned lasers whose beatnotes induce stimulated Raman transitions that couple virtually to collective phonon modes of the ion motion. The Ising couplings are controlled, both in sign and strength with respect to the effective transverse field, and adiabatically manipulated to study various aspects of this spin model, such as the emergence of a quantum phase transition in the ground state and spin frustration due to competing antiferromagnetic interactions. Spin frustration often gives rise to a massive degeneracy in the ground state, which can lead to entanglement in the spin system. We detect and characterize this frustration induced entanglement in a system of three spins, demonstrating the first direct experimental connection between frustration and entanglement. With larger numbers of spins we also vary the range of the antiferromagnetic couplings through appropriate laser tunings and observe that longer range interactions reduce the excitation energy and thereby frustrate the ground state order. This system can potentially be scaled up to study a wide range of fully connected spin networks with a few dozens of spins, where the underlying theory becomes intractable on a classical computer.
Measuring emotions during epistemic activities: the Epistemically-Related Emotion Scales.
Pekrun, Reinhard; Vogl, Elisabeth; Muis, Krista R; Sinatra, Gale M
2017-09-01
Measurement instruments assessing multiple emotions during epistemic activities are largely lacking. We describe the construction and validation of the Epistemically-Related Emotion Scales, which measure surprise, curiosity, enjoyment, confusion, anxiety, frustration, and boredom occurring during epistemic cognitive activities. The instrument was tested in a multinational study of emotions during learning from conflicting texts (N = 438 university students from the United States, Canada, and Germany). The findings document the reliability, internal validity, and external validity of the instrument. A seven-factor model best fit the data, suggesting that epistemically-related emotions should be conceptualised in terms of discrete emotion categories, and the scales showed metric invariance across the North American and German samples. Furthermore, emotion scores changed over time as a function of conflicting task information and related significantly to perceived task value and use of cognitive and metacognitive learning strategies.
A Decade of Genetic and Metabolomic Contributions to Type 2 Diabetes Risk Prediction
Merino, Jordi; Leong, Aaron; Meigs, James B.
2018-01-01
Purpose of Review The purpose of this review was to summarize and reflect on advances over the past decade in human genetic and metabolomic discovery with particular focus on their contributions to type 2 diabetes (T2D) risk prediction. Recent Findings In the past 10 years, a combination of advances in genotyping efficiency, metabolomic profiling, bio-informatics approaches, and international collaboration have moved T2D genetics and metabolomics from a state of frustration to an abundance of new knowledge. Summary Efforts to control and prevent T2D have failed to stop this global epidemic. New approaches are needed, and although neither genetic nor metabolomic profiling yet have a clear clinical role, the rapid pace of accumulating knowledge offers the possibility for “multi-omic” prediction to improve health. PMID:29103096
Does Time Fly When You Are Having Fun? A Day Reconstruction Method Analysis
Freedman, Vicki A.; Conrad, Frederick; Cornman, Jennifer; Schwarz, Norbert; Stafford, Frank
2013-01-01
Duration-based measures of happiness from retrospectively constructed daily diaries are gaining in popularity in population-based studies of the hedonic experience. Yet experimental evidence suggests that perceptions of duration – how long an event lasts – are influenced by individuals’ emotional experiences during the event. An important remaining question is whether observational measures of duration outside the laboratory setting, where the events under study are engaged in voluntarily, may be similarly affected, and if so, for which emotions are duration biases a potential concern. This study assesses how duration and emotions co-vary using retrospective, 24-hour diaries from a national sample of older couples. Data are from the Disability and Use of Time (DUST) supplement to the nationally representative U.S. Panel Study of Income Dynamics. We find that experienced wellbeing (positive, negative emotion) and activity duration are inversely associated. Specific positive emotions (happy, calm) are not associated with duration, but all measures of negative wellbeing considered here (frustrated, worried, sad, tired, and pain) have positive correlations (ranging from 0.04 to 0.08; p<.05). However, only frustration remains correlated with duration after controlling for respondent, activity and day-related characteristics (0.06, p<.01). The correlation translates into a potentially upward biased estimate of duration of up to 10 minutes (20%) for very frustrating activities. We conclude that estimates of time spent feeling happy yesterday generated from diary data are unlikely to be biased but more research is needed on the link between duration estimation and feelings of frustration. PMID:25110460
Tanner, Craig E; Eckstrom, Elizabeth; Desai, Sima S; Joseph, Carol L; Ririe, Marnie R; Bowen, Judith L
2006-01-01
General internists commonly provide medical care for older adults and geriatric education to trainees, but lack the necessary knowledge and skills to fulfill these tasks. Assess the geriatric training needs of academic general internists in 3 hospital systems in Portland, OR. Ten focus groups and 1 semi-structured interview. Interview transcripts were analyzed using thematic analysis, a well-recognized qualitative technique. A convenience sample of 22 academic general internists and 8 geriatricians from 3 different teaching hospitals. We elicited stories of frustration and success in caring for elderly patients and in teaching about their care. We asked geriatricians to recount their experiences as consultants to general internists and to comment on the training of Internists in geriatrics. In addition to deficits in their medical knowledge and skills, our Internists reported frustration with the process of delivering care to older adults. In particular, they felt ill prepared to guide care transitions for patients, use multidisciplinary teams effectively, and were frustrated with health care system issues. Additionally, general internists' approach to medical care, which largely relies on the medical model, is different from that of geriatricians, which focuses more on social and functional issues. Although our findings may not be broadly representative, improving our general internists' abilities to care for the elderly and to teach learners how to do the same should address deficits in medical knowledge and skills, barriers to the processes of delivering care, and philosophical approaches to care. Prioritizing and quantifying these needs and measuring the effectiveness of curricula to address them are areas for future research.
Shaffer, J Scott; Moore, Penny L; Kardar, Mehran; Chakraborty, Arup K
2016-10-24
Strategies to elicit Abs that can neutralize diverse strains of a highly mutable pathogen are likely to result in a potent vaccine. Broadly neutralizing Abs (bnAbs) against HIV have been isolated from patients, proving that the human immune system can evolve them. Using computer simulations and theory, we study immunization with diverse mixtures of variant antigens (Ags). Our results show that particular choices for the number of variant Ags and the mutational distances separating them maximize the probability of inducing bnAbs. The variant Ags represent potentially conflicting selection forces that can frustrate the Darwinian evolutionary process of affinity maturation. An intermediate level of frustration maximizes the chance of evolving bnAbs. A simple model makes vivid the origin of this principle of optimal frustration. Our results, combined with past studies, suggest that an appropriately chosen permutation of immunization with an optimally designed mixture (using the principles that we describe) and sequential immunization with variant Ags that are separated by relatively large mutational distances may best promote the evolution of bnAbs.
Frustrated proximity effects between s and s± superconductors
NASA Astrophysics Data System (ADS)
Stanev, Valentin; Koshelev, Alexei E.
2011-03-01
The nature of the superconducting order parameter (OP) in iron pnictides and chalcogenides is a hotly debated issue. It was theoretically proposed that the OP has opposite signs on the hole and the electron bands, i.e., it belongs to the unconventional class of s +/- (or extended s)-wave. There are, however, very few experiments that can directly distinguish this state from the ordinary s-wave OP. One way to address this problem is to study the proximity effects in a sandwich composed of conventional and iron pnictide superconductors (SC). If the pnictides indeed have the s +/- OP this system is intrinsically frustrated. In the case of strong frustration, a time-reversal symmetry-breaking (TRSB) SC state emerges, in which the OP phases in different bands are tilted at an angle, different from π , and controlled by the coupling strength. Observation of such state in the iron-based SC materials would give definite evidence for the s +/- OP. We present a microscopic, fully self-consistent approach to this problem, based on Usadel equations. We have studied the conditions for existence of the TRSB state and its experimental signatures.
Bidirectional Relations between Temperament and Parenting Styles in Chinese Children
Lee, Erica H.; Zhou, Qing; Eisenberg, Nancy; Wang, Yun
2012-01-01
The present study examined bidirectional relations between child temperament and parenting styles in a sample (n = 425) of Chinese children during elementary school period (age range = 6 to 9 years at Wave 1). Using two waves (3.8 years apart) of longitudinal data, we tested two hypotheses: (1) whether child temperament (effortful control and anger/frustration) at Wave 1 predicts parenting styles (authoritative and authoritarian parenting) at Wave 2, controlling for Wave 1 parenting; and (2) whether parenting styles at Wave 1 predict Wave 2 temperament, controlling for Wave 1 temperament. We found support for bidirectional relations between temperament and authoritarian parenting, such that higher effortful control and lower anger/frustration were associated with higher authoritarian parenting across time and in both directions. There were no significant cross-time associations between children’s temperament and authoritative parenting. These findings extend the previous tests of transactional relations between child temperament and parenting in Chinese children and are consistent with the cultural values toward effortful control and control of anger/frustration in Chinese society. PMID:23482684
Shaffer, J. Scott; Moore, Penny L.; Kardar, Mehran; Chakraborty, Arup K.
2016-01-01
Strategies to elicit Abs that can neutralize diverse strains of a highly mutable pathogen are likely to result in a potent vaccine. Broadly neutralizing Abs (bnAbs) against HIV have been isolated from patients, proving that the human immune system can evolve them. Using computer simulations and theory, we study immunization with diverse mixtures of variant antigens (Ags). Our results show that particular choices for the number of variant Ags and the mutational distances separating them maximize the probability of inducing bnAbs. The variant Ags represent potentially conflicting selection forces that can frustrate the Darwinian evolutionary process of affinity maturation. An intermediate level of frustration maximizes the chance of evolving bnAbs. A simple model makes vivid the origin of this principle of optimal frustration. Our results, combined with past studies, suggest that an appropriately chosen permutation of immunization with an optimally designed mixture (using the principles that we describe) and sequential immunization with variant Ags that are separated by relatively large mutational distances may best promote the evolution of bnAbs. PMID:27791170
Costa, Sebastiano; Gugliandolo, Maria C; Barberis, Nadia; Larcan, Rosalba
2016-02-01
Relatively few studies have examined the relationship between conception of God and psychological outcomes in a self-determination theory (SDT) framework. The aim of this study was to examine the role of basic psychological needs as a mediator of the association between conception of God and psychological outcomes. In a sample of 210 religious young adults, we found that the concept of a controlling God was positively associated with feelings of need frustration and depression, whilst the concept of an autonomy-supporting God was positively associated with feelings of need satisfaction and vitality. In turn, need satisfaction promoted feelings of vitality, whereas need frustration led to feelings of depression. The satisfaction of needs was a full mediator of the relationship between autonomy-supporting God and vitality, whilst the frustration of needs was a full mediator of the relationship between controlling God and depression. These findings are discussed in terms of SDT. We also discuss how future research may further increase our understanding of the dynamics involved in concepts of God and psychological outcomes.
Nature and Nurturing: Parenting in the Context of Child Temperament
Kiff, Cara J.; Lengua, Liliana J.; Zalewski, Maureen
2011-01-01
Accounting for both bidirectional and interactive effects between parenting and child temperament can fine-tune theoretical models of the role of parenting and temperament in children's development of adjustment problems. Evidence for bidirectional and interactive effects between parenting and children's characteristics of frustration, fear, self-regulation, and impulsivity was reviewed, and an overall model of children's individual differences in response to parenting is proposed. In general, children high in frustration, impulsivity and low in effortful control are more vulnerable to the adverse effects of negative parenting, while in turn, many negative parenting behaviors predict increases in these characteristics. Frustration, fearfulness, and effortful control also appear to elicit parenting behaviors that can predict increases in these characteristics. Irritability renders children more susceptible to negative parenting behaviors. Fearfulness operates in a very complex manner, sometimes increasing children's responses to parenting behaviors and sometimes mitigating them and apparently operating differently across gender. Important directions for future research include the use of study designs and analytic approaches that account for the direction of effects and for developmental changes in parenting and temperament over time. PMID:21461681
Bistable director alignments of nematic liquid crystals confined in frustrated substrates
NASA Astrophysics Data System (ADS)
Araki, Takeaki; Nagura, Jumpei
2017-01-01
We studied in-plane bistable alignments of nematic liquid crystals confined by two frustrated surfaces by means of Monte Carlo simulations of the Lebwohl-Lasher spin model. The surfaces are prepared with orientational checkerboard patterns, on which the director field is locally anchored to be planar yet orthogonal between the neighboring blocks. We found the director field in the bulk tends to be aligned along the diagonal axes of the checkerboard pattern, as reported experimentally [J.-H. Kim et al., Appl. Phys. Lett. 78, 3055 (2001), 10.1063/1.1371246]. The energy barrier between the two stable orientations is increased, when the system is brought to the isotropic-nematic transition temperature. Based on an elastic theory, we found that the bistability is attributed to the spatial modulation of the director field near the frustrated surfaces. As the block size is increased and/or the elastic modulus is reduced, the degree of the director inhomogeneity is increased, enlarging the energy barrier. We also found that the switching rate between the stable states is decreased when the block size is comparable to the cell thickness.
Foam morphology, frustration and topological defects in a Negatively curved Hele-Shaw geometry
NASA Astrophysics Data System (ADS)
Mughal, Adil; Schroeder-Turk, Gerd; Evans, Myfanwy
2014-03-01
We present preliminary simulations of foams and single bubbles confined in a narrow gap between parallel surfaces. Unlike previous work, in which the bounding surfaces are flat (the so called Hele-Shaw geometry), we consider surfaces with non-vanishing Gaussian curvature. We demonstrate that the curvature of the bounding surfaces induce a geometric frustration in the preferred order of the foam. This frustration can be relieved by the introduction of topological defects (disclinations, dislocations and complex scar arrangements). We give a detailed analysis of these defects for foams confined in curved Hele-Shaw cells and compare our results with exotic honeycombs, built by bees on surfaces of varying Gaussian curvature. Our simulations, while encompassing surfaces of constant Gaussian curvature (such as the sphere and the cylinder), focus on surfaces with negative Gaussian curvature and in particular triply periodic minimal surfaces (such as the Schwarz P-surface and the Schoen's Gyroid surface). We use the results from a sphere-packing algorithm to generate a Voronoi partition that forms the basis of a Surface Evolver simulation, which yields a realistic foam morphology.
Ultra-robust high-field magnetization plateau and supersolidity in bond-frustrated MnCr2S4
Tsurkan, Vladimir; Zherlitsyn, Sergei; Prodan, Lilian; Felea, Viorel; Cong, Pham Thanh; Skourski, Yurii; Wang, Zhe; Deisenhofer, Joachim; von Nidda, Hans-Albrecht Krug; Wosnitza, Joahim; Loidl, Alois
2017-01-01
Frustrated magnets provide a promising avenue for realizing exotic quantum states of matter, such as spin liquids and spin ice or complex spin molecules. Under an external magnetic field, frustrated magnets can exhibit fractional magnetization plateaus related to definite spin patterns stabilized by field-induced lattice distortions. Magnetization and ultrasound experiments in MnCr2S4 up to 60 T reveal two fascinating features: (i) an extremely robust magnetization plateau with an unusual spin structure and (ii) two intermediate phases, indicating possible realizations of supersolid phases. The magnetization plateau characterizes fully polarized chromium moments, without any contributions from manganese spins. At 40 T, the middle of the plateau, a regime evolves, where sound waves propagate almost without dissipation. The external magnetic field exactly compensates the Cr–Mn exchange field and decouples Mn and Cr sublattices. In analogy to predictions of quantum lattice-gas models, the changes of the spin order of the manganese ions at the phase boundaries of the magnetization plateau are interpreted as transitions to supersolid phases. PMID:28345038
Geometrical aspects of the frustration in the cubic phases of lyotropic liquid crystals.
Anderson, D M; Gruner, S M; Leibler, S
1988-01-01
Bicontinuous cubic phases, composed of bilayers arranged in the geometries of periodic minimal surfaces, are found in a variety of different lipid/water systems. It has been suggested recently that these cubic structures arrive as the result of competition between two free-energy terms: the curvature energy of each monolayer and the stretching energy of the lipid chains. This scenario, closely analogous to the one that explains the origin of the hexagonal phases, is investigated here by means of simple geometrical calculations. It is first assumed that the lipid bilayer is of constant thickness and the distribution of the (local) mean curvature of the phospholipid-water interfaces is calculated. Then, assuming the mean curvature of these interfaces is constant, the distribution of the bilayer's thickness is calculated. Both calculations quantify the fact that the two energy terms are frustrated and cannot be satisfied simultaneously. However, the amount of the frustration can be smaller for the cubic phase than for the lamellar and hexagonal structures. Therefore, this phase can appear in the phase diagram between the other two, as observed in many recent experiments. PMID:3399497
Granato, Enzo
2008-07-11
Phase coherence and vortex order in a Josephson-junction array at irrational frustration are studied by extensive Monte Carlo simulations using the parallel-tempering method. A scaling analysis of the correlation length of phase variables in the full equilibrated system shows that the critical temperature vanishes with a power-law divergent correlation length and critical exponent nuph, in agreement with recent results from resistivity scaling analysis. A similar scaling analysis for vortex variables reveals a different critical exponent nuv, suggesting that there are two distinct correlation lengths associated with a decoupled zero-temperature phase transition.
Evolved Minimal Frustration in Multifunctional Biomolecules.
Röder, Konstantin; Wales, David J
2018-05-25
Protein folding is often viewed in terms of a funnelled potential or free energy landscape. A variety of experiments now indicate the existence of multifunnel landscapes, associated with multifunctional biomolecules. Here, we present evidence that these systems have evolved to exhibit the minimal number of funnels required to fulfil their cellular functions, suggesting an extension to the principle of minimum frustration. We find that minimal disruptive mutations result in additional funnels, and the associated structural ensembles become more diverse. The same trends are observed in an atomic cluster. These observations suggest guidelines for rational design of engineered multifunctional biomolecules.
Goli, V M L Durga Prasad; Sahoo, Shaon; Ramasesha, S; Sen, Diptiman
2013-03-27
We study here different regions in phase diagrams of the spin-1/2, spin-1 and spin-3/2 one-dimensional antiferromagnetic Heisenberg systems with frustration (next-nearest-neighbor interaction J2) and dimerization (δ). In particular, we analyze the behaviors of the bipartite entanglement entropy and fidelity at the gapless to gapped phase transitions and across the lines separating different phases in the J2-δ plane. All the calculations in this work are based on numerical exact diagonalizations of finite systems.
Phase-space networks of geometrically frustrated systems.
Han, Yilong
2009-11-01
We illustrate a network approach to the phase-space study by using two geometrical frustration models: antiferromagnet on triangular lattice and square ice. Their highly degenerated ground states are mapped as discrete networks such that the quantitative network analysis can be applied to phase-space studies. The resulting phase spaces share some comon features and establish a class of complex networks with unique Gaussian spectral densities. Although phase-space networks are heterogeneously connected, the systems are still ergodic due to the random Poisson processes. This network approach can be generalized to phase spaces of some other complex systems.
Symptoms and Character Traits in Patients Selected for Long-term Psychodynamic Psychotherapy
Wilczek, Alexander; Weinryb, Robert M.; Gustavsson, Petter J.; Barber, Jacques P.; Schubert, Johan; ÅSBERG, Marie
1998-01-01
In this naturalistic study of 55 outpatients selected for long-term psychodynamic psychotherapy, two Swedish assessment instruments are presented (the Karolinska Psychodynamic Profile and the Karolinska Scales of Personality), and the significance of psychodynamic criteria for the selection of patients is discussed. Thirty patients (55%) fulfilled criteria for a DSM-III-R diagnosis. The most prominent psychodynamically defined character pathology was found in the areas of coping with aggressive affects; dependency and separation; frustration tolerance; and impulse control. Some psychodynamically defined character traits, particularly poor frustration tolerance, were related to symptomatic suffering. PMID:9407473
Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB 4
Sunku, Sai Swaroop; Kong, Tai; Ito, Toshimitsu; ...
2016-05-11
We study TmB 4, a frustrated magnet on the Archimedean Shastry-Sutherland lattice, through magnetization and transport experiments. The lack of anisotropy in resistivity shows that TmB4 is an electronically three-dimensional system. The magnetoresistance (MR) is hysteretic at low temperature even though a corresponding hysteresis in magnetization is absent. The Hall resistivity shows unconventional anomalous Hall effect (AHE) and is linear above saturation despite a large MR. In conclusion, we propose that complex structures at magnetic domain walls may be responsible for the hysteretic MR and may also lead to the AHE.
Hidden transition in multiferroic and magnetodielectric CuCrO2 evidenced by ac-susceptibility
NASA Astrophysics Data System (ADS)
Shukla, Kaushak K.; Pal, Arkadeb; Singh, Abhishek; Singh, Rahul; Saha, J.; Sinha, A. K.; Ghosh, A. K.; Patnaik, S.; Awasthi, A. M.; Chatterjee, Sandip
2017-04-01
Ferroelectric polarization, magnetic-field dependence of the dielectric constant and ac and dc magnetizations of frustrated CuCrO2 have been measured. A new spin freezing transition below 32 K is observed which is thermally driven. The nature of the spin freezing is to be a single-ion process. Dilution by the replacements of Cr ions by magnetic Mn ions showed suppression of the spin freezing transition suggesting it to be fundamentally a single-ion freezing process. The observed freezing, which is seemingly associated to geometrical spin frustration, represents a novel form of magnetic glassy behavior.
Structural and transport properties of Yb substituted YBaCo4O7
NASA Astrophysics Data System (ADS)
Singh, Bharat; Kumar, Naresh; Gaur, N. K.; Rayaprol, S.
2012-06-01
We investigate a series of compounds of the type, Y1-xYbxBaCo4O7, to study the effect of chemical pressure on the structural and electrical transport properties of a geometrically frustrated cobaltite, YBaCo4O7. Rietveld analysis of XRD data were carried out for all the samples studied. The four probe resistivity measurements were carried out to understand the transport mechanism in these compounds at temperatures below room temperatures. These results are presented and discussed in the context of ongoing efforts in studying geometrically frustrated magnetic compounds with novel physical properties.
Remote Synchronization Reveals Network Symmetries and Functional Modules
NASA Astrophysics Data System (ADS)
Nicosia, Vincenzo; Valencia, Miguel; Chavez, Mario; Díaz-Guilera, Albert; Latora, Vito
2013-04-01
We study a Kuramoto model in which the oscillators are associated with the nodes of a complex network and the interactions include a phase frustration, thus preventing full synchronization. The system organizes into a regime of remote synchronization where pairs of nodes with the same network symmetry are fully synchronized, despite their distance on the graph. We provide analytical arguments to explain this result, and we show how the frustration parameter affects the distribution of phases. An application to brain networks suggests that anatomical symmetry plays a role in neural synchronization by determining correlated functional modules across distant locations.
Pairing from strong repulsion in triangular lattice Hubbard model
NASA Astrophysics Data System (ADS)
Zhang, Shang-Shun; Zhu, Wei; Batista, Cristian D.
2018-04-01
We propose a pairing mechanism between holes in the dilute limit of doped frustrated Mott insulators. Hole pairing arises from a hole-hole-magnon three-body bound state. This pairing mechanism has its roots on single-hole kinetic energy frustration, which favors antiferromagnetic (AFM) correlations around the hole. We demonstrate that the AFM polaron (hole-magnon bound state) produced by a single hole propagating on a field-induced polarized background is strong enough to bind a second hole. The effective interaction between these three-body bound states is repulsive, implying that this pairing mechanism is relevant for superconductivity.
Elasticity and Fluctuations of Frustrated Nanoribbons
NASA Astrophysics Data System (ADS)
Grossman, Doron; Sharon, Eran; Diamant, Haim
2016-06-01
We derive a reduced quasi-one-dimensional theory of geometrically frustrated elastic ribbons. Expressed in terms of geometric properties alone, it applies to ribbons over a wide range of scales, allowing the study of their elastic equilibrium, as well as thermal fluctuations. We use the theory to account for the twisted-to-helical transition of ribbons with spontaneous negative curvature and the effect of fluctuations on the corresponding critical exponents. The persistence length of such ribbons changes nonmonotonically with the ribbon's width, dropping to zero at the transition. This and other statistical properties qualitatively differ from those of nonfrustrated fluctuating filaments.
Properties of highly frustrated magnetic molecules studied by the finite-temperature Lanczos method
NASA Astrophysics Data System (ADS)
Schnack, J.; Wendland, O.
2010-12-01
The very interesting magnetic properties of frustrated magnetic molecules are often hardly accessible due to the prohibitive size of the related Hilbert spaces. The finite-temperature Lanczos method is able to treat spin systems for Hilbert space sizes up to 109. Here we first demonstrate for exactly solvable systems that the method is indeed accurate. Then we discuss the thermal properties of one of the biggest magnetic molecules synthesized to date, the icosidodecahedron with antiferromagnetically coupled spins of s = 1/2. We show how genuine quantum features such as the magnetization plateau behave as a function of temperature.
Spiculated Bladder Calculi: The Culprit for Repeated Catheter Failure
Wek, C.; Fox, T. P.; Muir, G. H.
2013-01-01
We report on the case of a frustrated 90-year-old gentleman who was seen in the Accident and Emergency department for the third time in four days with failure of his long-term urethral catheter. He reported that the catheter simply “fell out” with the balloon deflated. On each occasion previously, the catheter had been reinserted in A&E and the patient discharged home. These repeated visits to A&E were understandably a source of much frustration for the patient and his family. On the third presentation, plain abdominal radiography demonstrated a large spiculated bladder calculus. PMID:23984173
Bound States in Dimerized and Frustrated Heisenberg Chains
NASA Astrophysics Data System (ADS)
Bouzerar, G.; Sil, S.
Using the Bond-Operator Technique (BOT), we have studied the low energy excitation spectrum of a frustrated dimerized antiferromagnetic Heisenberg chain. In particular, we have compared our analytical results with previous Exact Diagonalization (ED) data. Qualitatively, the BOT results are in good agreement with the ED data. And even a very good quantitative agreement is obtained in some parameter region. It is clearly shown that there is only one elementary excitation branch (lowest triplet branch) and that the two other well defined excitations which appear below the continuum, one singlet and one triplet, are bound states of two elementary triplets.
The Role of High-Dimensional Diffusive Search, Stabilization, and Frustration in Protein Folding
Rimratchada, Supreecha; McLeish, Tom C.B.; Radford, Sheena E.; Paci, Emanuele
2014-01-01
Proteins are polymeric molecules with many degrees of conformational freedom whose internal energetic interactions are typically screened to small distances. Therefore, in the high-dimensional conformation space of a protein, the energy landscape is locally relatively flat, in contrast to low-dimensional representations, where, because of the induced entropic contribution to the full free energy, it appears funnel-like. Proteins explore the conformation space by searching these flat subspaces to find a narrow energetic alley that we call a hypergutter and then explore the next, lower-dimensional, subspace. Such a framework provides an effective representation of the energy landscape and folding kinetics that does justice to the essential characteristic of high-dimensionality of the search-space. It also illuminates the important role of nonnative interactions in defining folding pathways. This principle is here illustrated using a coarse-grained model of a family of three-helix bundle proteins whose conformations, once secondary structure has formed, can be defined by six rotational degrees of freedom. Two folding mechanisms are possible, one of which involves an intermediate. The stabilization of intermediate subspaces (or states in low-dimensional projection) in protein folding can either speed up or slow down the folding rate depending on the amount of native and nonnative contacts made in those subspaces. The folding rate increases due to reduced-dimension pathways arising from the mere presence of intermediate states, but decreases if the contacts in the intermediate are very stable and introduce sizeable topological or energetic frustration that needs to be overcome. Remarkably, the hypergutter framework, although depending on just a few physically meaningful parameters, can reproduce all the types of experimentally observed curvature in chevron plots for realizations of this fold. PMID:24739172
Briones-Vozmediano, Erica
2016-01-01
This article is a review of the PhD thesis written by Erica Briones-Vozmediano, entitled, ‘The social construction of fibromyalgia as a health problem from the perspective of policies, professionals, and patients’. The findings show that in Spain, the fact that fibromyalgia (FM) lacks recognition still remains: in policies, in the clinical and professional fields, and in the patients’ social circle. These three spheres have an influence on how this disease is constructed on a social level. International health policy has not yet taken steps to reflect the emergence of this recently diagnosed disease. The care for patients suffering from FM, who are mainly women, leads to frustration among the healthcare professionals and desperation among the patients themselves, as a resolutive treatment for the disease is not existing. Patients show resistance at assuming the sick role. They want to carry on undertaking their daily activities, both in the public sphere and in the private one. Roles involving the gendered division of labour were found to follow a rigid pattern, both prior to and subsequent to the disease, as the causes that led to frustration for men or women differ according to activities that are socially assigned to them. In practice, FM is conceived exclusively as a women’s health problem, which may result in a gender-biased patient healthcare attention. It is recommended that the implementation of specific policies for FM which could resolve this evident shortcoming should take place. To draw attention on a social level to certain illnesses considered to be attributed to women, such as FM, is of utmost importance, in order to allow the patients to be socially recognised as suffering a real and disabling disease. PMID:27989274
Approximating frustration scores in complex networks via perturbed Laplacian spectra
NASA Astrophysics Data System (ADS)
Savol, Andrej J.; Chennubhotla, Chakra S.
2015-12-01
Systems of many interacting components, as found in physics, biology, infrastructure, and the social sciences, are often modeled by simple networks of nodes and edges. The real-world systems frequently confront outside intervention or internal damage whose impact must be predicted or minimized, and such perturbations are then mimicked in the models by altering nodes or edges. This leads to the broad issue of how to best quantify changes in a model network after some type of perturbation. In the case of node removal there are many centrality metrics which associate a scalar quantity with the removed node, but it can be difficult to associate the quantities with some intuitive aspect of physical behavior in the network. This presents a serious hurdle to the application of network theory: real-world utility networks are rarely altered according to theoretic principles unless the kinetic impact on the network's users are fully appreciated beforehand. In pursuit of a kinetically interpretable centrality score, we discuss the f-score, or frustration score. Each f-score quantifies whether a selected node accelerates or inhibits global mean first passage times to a second, independently selected target node. We show that this is a natural way of revealing the dynamical importance of a node in some networks. After discussing merits of the f-score metric, we combine spectral and Laplacian matrix theory in order to quickly approximate the exact f-score values, which can otherwise be expensive to compute. Following tests on both synthetic and real medium-sized networks, we report f-score runtime improvements over exact brute force approaches in the range of 0 to 400 % with low error (<3 % ).
Personality traits in companion dogs-Results from the VIDOPET.
Turcsán, Borbála; Wallis, Lisa; Virányi, Zsófia; Range, Friederike; Müller, Corsin A; Huber, Ludwig; Riemer, Stefanie
2018-01-01
Individual behavioural differences in pet dogs are of great interest from a basic and applied research perspective. Most existing dog personality tests have specific (practical) goals in mind and so focused only on a limited aspect of dogs' personality, such as identifying problematic (aggressive or fearful) behaviours, assessing suitability as working dogs, or improving the results of adoption. Here we aimed to create a comprehensive test of personality in pet dogs that goes beyond traditional practical evaluations by exposing pet dogs to a range of situations they might encounter in everyday life. The Vienna Dog Personality Test (VIDOPET) consists of 15 subtests and was performed on 217 pet dogs. A two-step data reduction procedure (principal component analysis on each subtest followed by an exploratory factor analysis on the subtest components) yielded five factors: Sociability-obedience, Activity-independence, Novelty seeking, Problem orientation, and Frustration tolerance. A comprehensive evaluation of reliability and validity measures demonstrated excellent inter- and intra-observer reliability and adequate internal consistency of all factors. Moreover the test showed good temporal consistency when re-testing a subsample of dogs after an average of 3.8 years-a considerably longer test-retest interval than assessed for any other dog personality test, to our knowledge. The construct validity of the test was investigated by analysing the correlations between the results of video coding and video rating methods and the owners' assessment via a dog personality questionnaire. The results demonstrated good convergent as well as discriminant validity. To conclude, the VIDOPET is not only a highly reliable and valid tool for measuring dog personality, but also the first test to show consistent behavioural traits related to problem solving ability and frustration tolerance in pet dogs.
Building bridges: engaging medical residents in quality improvement and medical leadership.
Voogt, Judith J; van Rensen, Elizabeth L J; van der Schaaf, Marieke F; Noordegraaf, Mirko; Schneider, Margriet Me
2016-12-01
To develop an educational intervention that targets residents' beliefs and attitudes to quality Improvement (QI) and leadership in order to demonstrate proactive behaviour. Theory-driven, mixed methods study including document analysis, interviews, observations and open-ended questionnaires. Six Dutch teaching hospitals. Using expertise from medicine, psychology, organizational and educational sciences we developed a situated learning programme named Ponder and IMProve (PIMP). The acronym PIMP reflects the original upbeat name in Dutch, Verwonder & Verbeter. It has a modern, positive meaning that relates to improving your current circumstances. In quarterly 1-h sessions residents are challenged to identify daily workplace frustrations and translate them into small-scale QI activities. Organizational awareness, beliefs and attitudes to QI and organizational responsibilities, resident behaviour, barriers and facilitators to successful learning and the programme's potential impact on the organization. Overall, 19 PIMP meetings were held over a period of 3 years. Residents defined 119 PIMP goals, resolved 37 projects and are currently working on another 39 projects. Interviews show that PIMP sessions make residents more aware of the organizational aspects of their daily work. Moreover, residents feel empowered to take up the role of change agent. Facilitators for success include a positive cost-benefit trade-off, a valuable group process and a safe learning environment. This article demonstrates the added value of multidisciplinary theory-driven research for the design, development and evaluation of educational programmes. Residents can be encouraged to develop organizational awareness and reshape their daily frustrations in QI work. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
Wensley, Beth G.; Kwa, Lee Gyan; Shammas, Sarah L.; Rogers, Joseph M.; Browning, Stuart; Yang, Ziqi; Clarke, Jane
2012-01-01
The elongated three-helix bundle domains spectrin R16 and R17 fold some two to three orders of magnitude more slowly than their homologue R15. We have shown that this slow folding is due, at least in part, to roughness in the free-energy landscape of R16 and R17. We have proposed that this roughness is due to a frustrated search for the correct docking of partly preformed helices. However, this accounts for only a small part of the slowing of folding and unfolding. Five residues on the A helix of R15, when inserted together into R16 or R17, increase the folding rate constants, reduce landscape roughness, and alter the folding mechanism to one resembling R15. The effect of each of these mutations individually is investigated here. No one mutation causes the behavior seen for the five in combination. However, two mutations, E18F and K25V, significantly increase the folding and unfolding rates of both R16 and R17 but without a concomitant loss in landscape roughness. E18F has the greatest effect on the kinetics, and a Φ-value analysis of the C helix reveals that the folding mechanism is unchanged. For both E18F and K25V the removal of the charge and resultant transition state stabilization is the main origin of the faster folding. Consequently, the major cause of the unusually slow folding of R16 and R17 is the non-native burial of the two charged residues in the transition state. The slowing due to landscape roughness is only about fivefold. PMID:22711800
Wensley, Beth G; Kwa, Lee Gyan; Shammas, Sarah L; Rogers, Joseph M; Browning, Stuart; Yang, Ziqi; Clarke, Jane
2012-10-30
The elongated three-helix bundle domains spectrin R16 and R17 fold some two to three orders of magnitude more slowly than their homologue R15. We have shown that this slow folding is due, at least in part, to roughness in the free-energy landscape of R16 and R17. We have proposed that this roughness is due to a frustrated search for the correct docking of partly preformed helices. However, this accounts for only a small part of the slowing of folding and unfolding. Five residues on the A helix of R15, when inserted together into R16 or R17, increase the folding rate constants, reduce landscape roughness, and alter the folding mechanism to one resembling R15. The effect of each of these mutations individually is investigated here. No one mutation causes the behavior seen for the five in combination. However, two mutations, E18F and K25V, significantly increase the folding and unfolding rates of both R16 and R17 but without a concomitant loss in landscape roughness. E18F has the greatest effect on the kinetics, and a Φ-value analysis of the C helix reveals that the folding mechanism is unchanged. For both E18F and K25V the removal of the charge and resultant transition state stabilization is the main origin of the faster folding. Consequently, the major cause of the unusually slow folding of R16 and R17 is the non-native burial of the two charged residues in the transition state. The slowing due to landscape roughness is only about fivefold.
Personality traits in companion dogs—Results from the VIDOPET
Wallis, Lisa; Virányi, Zsófia; Range, Friederike; Müller, Corsin A.; Huber, Ludwig; Riemer, Stefanie
2018-01-01
Individual behavioural differences in pet dogs are of great interest from a basic and applied research perspective. Most existing dog personality tests have specific (practical) goals in mind and so focused only on a limited aspect of dogs’ personality, such as identifying problematic (aggressive or fearful) behaviours, assessing suitability as working dogs, or improving the results of adoption. Here we aimed to create a comprehensive test of personality in pet dogs that goes beyond traditional practical evaluations by exposing pet dogs to a range of situations they might encounter in everyday life. The Vienna Dog Personality Test (VIDOPET) consists of 15 subtests and was performed on 217 pet dogs. A two-step data reduction procedure (principal component analysis on each subtest followed by an exploratory factor analysis on the subtest components) yielded five factors: Sociability-obedience, Activity-independence, Novelty seeking, Problem orientation, and Frustration tolerance. A comprehensive evaluation of reliability and validity measures demonstrated excellent inter- and intra-observer reliability and adequate internal consistency of all factors. Moreover the test showed good temporal consistency when re-testing a subsample of dogs after an average of 3.8 years—a considerably longer test-retest interval than assessed for any other dog personality test, to our knowledge. The construct validity of the test was investigated by analysing the correlations between the results of video coding and video rating methods and the owners’ assessment via a dog personality questionnaire. The results demonstrated good convergent as well as discriminant validity. To conclude, the VIDOPET is not only a highly reliable and valid tool for measuring dog personality, but also the first test to show consistent behavioural traits related to problem solving ability and frustration tolerance in pet dogs. PMID:29634747
Ordering and Excitations in the Field-Induced Magnetic Phase of Cs3Cr2Br9
NASA Astrophysics Data System (ADS)
Grenier, Beatrice
2006-03-01
Cs3Cr2Br9 is an interesting example of interacting spin-dimer system. As in other isotropic antiferromagnets such as Haldane or alternating chains and ladders, the ground state in zero field is a total spin singlet separated from the excited triplet by an energy gap. In a magnetic field H, a phase transition occurs at a critical field Hc1, where the gap to the lowest component of the Zeeman-split triplet closes. Above Hc1, field-induced magnetic order (FIMO) for spin components perpendicular to H is induced by inter-dimer or inter-chain couplings. The FIMO transition may be considered as a Bose-Einstein Condensation. Cs3Cr2Br9 differs from other dimer systems currently studied (e.g. PHCC, TlCuCl3) in two main ways: each Cr^3+ ion of the dimer has spin 3/2 rather than 1/2 for Cu-based systems and the arrangement of the dimers is hexagonal. This gives rise to anisotropy and frustration in a 3D lattice, respectively. The possibility of studying the magnetic ordering and the spin dynamics in a FIMO with sufficient detail to bring out features of frustration and anisotropy motivated the present neutron scattering study in Cs3Cr2Br9*. Two field orientations have been exploited, perpendicular and parallel to the easy axis c (direction of the dimers). First, I present the diffraction study: the FIMO displays large hysteresis incommensurability, showing the importance of frustration. The impact of anisotropy is seen in the magnetic structure, whose nature strongly depends on the field direction. Second, I focus on spin dynamics: it quantifies the presence of anisotropy and shows its crucial role on the energy gap at Hc1, which is measurably open or not, depending on whether H is perpendicular or parallel to c. Third, an explanation is proposed for the large value of the gap at higher field: it involves the mixing of higher order states (extended-FIMO), reflected by the absence of magnetization plateaus. Comparison with the sister Cs3Cr2Cl9 compound provides a test of this hypothesis. *B. Grenier et al., Phys. Rev. Lett. 92, 177202 (2004)
Ruan, Yue; Thabit, Hood; Leelarathna, Lalantha; Hartnell, Sara; Willinska, Malgorzata E; Dellweg, Sibylle; Benesch, Carsten; Mader, Julia K; Holzer, Manuel; Kojzar, Harald; Evans, Mark L; Pieber, Thomas R; Arnolds, Sabine; Hovorka, Roman
2016-05-01
To quantify variability of insulin requirements during closed-loop insulin delivery. We retrospectively analyzed overnight, daytime, and total daily insulin amounts delivered during a multicenter closed-loop trial involving 32 adults with type 1 diabetes. Participants applied hybrid day-and-night closed-loop insulin delivery under free-living home conditions over 12 weeks. The coefficient of variation was adopted to measure variability of insulin requirements in individual subjects. Data were analyzed from 1,918 nights, 1,883 daytime periods and 1,564 total days characterized by closed-loop use over 85% of time. Variability of overnight insulin requirements (mean [SD] coefficient of variation 31% [4]) was nearly twice as high as variability of total daily requirements (17% [3], P < 0.001) and was also higher than variability of daytime insulin requirements (22% [4], P < 0.001). Overnight insulin requirements were significantly more variable than daytime and total daily amounts. This may explain why some people with type 1 diabetes report frustrating variability in morning glycemia. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.
Working relationships between obstetric care staff and their managers: a critical incident analysis.
Chipeta, Effie; Bradley, Susan; Chimwaza-Manda, Wanangwa; McAuliffe, Eilish
2016-08-26
Malawi continues to experience critical shortages of key health technical cadres that can adequately respond to Malawi's disease burden. Difficult working conditions contribute to low morale and frustration among health care workers. We aimed to understand how obstetric care staff perceive their working relationships with managers. A qualitative exploratory study was conducted in health facilities in Malawi between October and December 2008. Critical Incident Analysis interviews were done in government district hospitals, faith-based health facilities, and a sample of health centres' providing emergency obstetric care. A total of 84 service providers were interviewed. Data were analyzed using NVivo 8 software. Poor leadership styles affected working relationships between obstetric care staff and their managers. Main concerns were managers' lack of support for staff welfare and staff performance, lack of mentorship for new staff and junior colleagues, as well as inadequate supportive supervision. All this led to frustrations, diminished motivation, lack of interest in their job and withdrawal from work, including staff seriously considering leaving their post. Positive working relationships between obstetric care staff and their managers are essential for promoting staff motivation and positive work performance. However, this study revealed that staff were demotivated and undermined by transactional leadership styles and behavior, evidenced by management by exception and lack of feedback or recognition. A shift to transformational leadership in nurse-manager relationships is essential to establish good working relationships with staff. Improved providers' job satisfaction and staff retentionare crucial to the provision of high quality care and will also ensure efficiency in health care delivery in Malawi.
Assessing the Role of the Family/Support System Perspective in Patients With Glaucoma.
Shtein, Roni M; Newman-Casey, Paula A; Herndon, Leon; Coleman, Anne L; Lee, Paul P
2016-07-01
To investigate the role of the family/friends support system for patients with glaucoma and their perspective on barriers to effective glaucoma management. Six focus groups were conducted in 3 geographically and ethnically diverse areas of the United States (Los Angeles, CA; Rochester, MN; Durham, NC) that included 31 participants; 68% (21/31) were family members and friends of glaucoma patients with poor vision and 32% (10/31) were support system individuals of patients with good vision. Content analysis was used to identify important themes. Semiquantitative analysis was used to measure the frequency of each theme. A total of 134 relevant comments were made in the 6 focus groups and 72% of relevant comments were made by individuals providing support for patients with poor vision. Family members and friends mentioned the following areas of concern regarding patients' glaucoma care: patient education (19.4%), doctor-patient relationship (17.9%), their own lack of involvement in the patient's medical care (17.2%), frustration with glaucoma and with the patient (14.9%), patient dependency on caregivers (14.9%), patient frustration with the disease (10.4%), and sex differences in coping mechanisms (5.2%). Support system individuals tend to be minimally involved in the patient's glaucoma status and care. This is especially true for support system members of patients with glaucoma who maintain good vision and those who do not have any other personal experiences with difficulties from glaucoma. Many of these family members express an interest in acquiring more education about glaucoma and becoming more involved in the patient's glaucoma care.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fatkin, L.T.; Hudgens, G.A.
1994-01-01
An investigation was conducted by the U.S. Army Research Laboratory (ARL) and funded by the Physiological and Psychological Effects of the Nuclear, Biological, and Chemical (NBC) Environment and Sustained Operations on Systems in Combat (P2NBC2) program to assess the psychological reactions of soldiers in mission-oriented protective posture (MOPP) IV participating in training in a simulated chemical agent environment and in a toxic agent environment. A total of 155 soldiers who participated in the basic course (junior enlisted) and the advanced courses (officer and noncommissioned officer NCO groups) as part of their military occupational specialty (MOS) training volunteered for the study.more » The junior enlisted group reported significant increases in anxiety during four sessions as they approached the toxic agent portion of the training. The more experienced groups showed a small, but significant increase in anxiety during sessions. Their level of hostility, a component of stress that usually relates to levels of personal frustration, decreased significantly from the time of their initial testing to just before the training began. Since the initial session occurred 1 to 2 weeks before the U.S. Army Chemical Defense Training Facility (CDTF) training, the elevated frustration level may be a reflection of their overall experiences within the intensive chemical defense training program. A significant drop in reported fatigue between the pre- and post-training sessions may indicate a certain level of vigilance gained by participating in the training.« less
Barriers to effective management of type 2 diabetes in primary care: qualitative systematic review
Rushforth, Bruno; McCrorie, Carolyn; Glidewell, Liz; Midgley, Eleanor; Foy, Robbie
2016-01-01
Background Despite the availability of evidence-based guidance, many patients with type 2 diabetes do not achieve treatment goals. Aim To guide quality improvement strategies for type 2 diabetes by synthesising qualitative evidence on primary care physicians’ and nurses’ perceived influences on care. Design and setting Systematic review of qualitative studies with findings organised using the Theoretical Domains Framework. Method Databases searched were MEDLINE, Embase, CINAHL, PsycInfo, and ASSIA from 1980 until March 2014. Studies included were English-language qualitative studies in primary care of physicians’ or nurses’ perceived influences on treatment goals for type 2 diabetes. Results A total of 32 studies were included: 17 address general diabetes care, 11 glycaemic control, three blood pressure, and one cholesterol control. Clinicians struggle to meet evolving treatment targets within limited time and resources, and are frustrated with resulting compromises. They lack confidence in knowledge of guidelines and skills, notably initiating insulin and facilitating patient behaviour change. Changing professional boundaries have resulted in uncertainty about where clinical responsibility resides. Accounts are often couched in emotional terms, especially frustrations over patient compliance and anxieties about treatment intensification. Conclusion Although resources are important, many barriers to improving care are amenable to behaviour change strategies. Improvement strategies need to account for differences between clinical targets and consider tailored rather than ‘one size fits all’ approaches. Training targeting knowledge is necessary but insufficient to bring about major change; approaches to improve diabetes care need to delineate roles and responsibilities, and address clinicians’ skills and emotions around treatment intensification and facilitation of patient behaviour change. PMID:26823263
Barriers to effective management of type 2 diabetes in primary care: qualitative systematic review.
Rushforth, Bruno; McCrorie, Carolyn; Glidewell, Liz; Midgley, Eleanor; Foy, Robbie
2016-02-01
Despite the availability of evidence-based guidance, many patients with type 2 diabetes do not achieve treatment goals. To guide quality improvement strategies for type 2 diabetes by synthesising qualitative evidence on primary care physicians' and nurses' perceived influences on care. Systematic review of qualitative studies with findings organised using the Theoretical Domains Framework. Databases searched were MEDLINE, Embase, CINAHL, PsycInfo, and ASSIA from 1980 until March 2014. Studies included were English-language qualitative studies in primary care of physicians' or nurses' perceived influences on treatment goals for type 2 diabetes. A total of 32 studies were included: 17 address general diabetes care, 11 glycaemic control, three blood pressure, and one cholesterol control. Clinicians struggle to meet evolving treatment targets within limited time and resources, and are frustrated with resulting compromises. They lack confidence in knowledge of guidelines and skills, notably initiating insulin and facilitating patient behaviour change. Changing professional boundaries have resulted in uncertainty about where clinical responsibility resides. Accounts are often couched in emotional terms, especially frustrations over patient compliance and anxieties about treatment intensification. Although resources are important, many barriers to improving care are amenable to behaviour change strategies. Improvement strategies need to account for differences between clinical targets and consider tailored rather than 'one size fits all' approaches. Training targeting knowledge is necessary but insufficient to bring about major change; approaches to improve diabetes care need to delineate roles and responsibilities, and address clinicians' skills and emotions around treatment intensification and facilitation of patient behaviour change. © British Journal of General Practice 2016.
Frustrated quantum magnetism in the Kondo lattice on the zigzag ladder
NASA Astrophysics Data System (ADS)
Peschke, Matthias; Rausch, Roman; Potthoff, Michael
2018-03-01
The interplay between the Kondo effect, indirect magnetic interaction, and geometrical frustration is studied in the Kondo lattice on the one-dimensional zigzag ladder. Using the density-matrix renormalization group, the ground-state and various short- and long-range spin- and density-correlation functions are calculated for the model at half filling as a function of the antiferromagnetic Kondo interaction down to J =0.3 t , where t is the nearest-neighbor hopping on the zigzag ladder. Geometrical frustration is shown to lead to at least two critical points: Starting from the strong-J limit, where almost local Kondo screening dominates and where the system is a nonmagnetic Kondo insulator, antiferromagnetic correlations between nearest-neighbor and next-nearest-neighbor local spins become stronger and stronger, until at Jcdim≈0.89 t frustration is alleviated by a spontaneous breaking of translational symmetry and a corresponding transition to a dimerized state. This is characterized by antiferromagnetic correlations along the legs and by alternating antiferro- and ferromagnetic correlations on the rungs of the ladder. A mechanism of partial Kondo screening that has been suggested for the Kondo lattice on the two-dimensional triangular lattice is not realized in the one-dimensional case. Furthermore, within the symmetry-broken dimerized state, there is a magnetic transition to a 90∘ quantum spin spiral with quasi-long-range order at Jcmag≈0.84 t . The quantum-critical point is characterized by a closure of the spin gap (with decreasing J ) and a divergence of the spin-correlation length and of the spin-structure factor S (q ) at wave vector q =π /2 . This is opposed to the model on the one-dimensional bipartite chain, which is known to have a finite spin gap for all J >0 at half filling.
Violence among peoples in the light of human frustration and aggression.
de Gaay Fortman, Bas
2005-12-05
This article sets out to provide a general background to the study of aggression in the social sciences, with a particular focus on its link to collective violence. While the study of what happens in the human brain appears to be already highly complex, analysis of violent behavior appears to be even more intricate. A deductive system in the sense of a general and clear system of propositions logically connected to one another is not feasible, principally because contrary to the natural sciences there are no verities but merely "stylized facts." One of these concerns the setting of human aggression in the light of frustration, as argued in the frustration-aggression hypothesis developed by Dollard et al. in 1939. Apart from conceiving of aggression as a pure human instinct, it may also be seen as externally driven, while a third possibility concerns culturally "learned" aggression. Proof of the latter is that the strongest correlation appears to be that between current violence and previous manifestations thereof. Attention is paid to the way in which Gurr has rooted his relative deprivation theory on causes of collective violence among peoples in mechanisms of frustration and aggression. That theory is taken a bit further in terms of "perceived acquirement failure," which appears to be highly connected to the role of the state. Based on certain observations by Hannah Arendt, the argument then proceeds to violence as a manifestation of powerlessness. Finally, this leads to a discussion of justice as a crucial factor in what Durkheim used to call a "right to conflict." In this way, human aggression is placed in a broad socio-economic context.
Geometries in Soft Matter From Geometric Frustration, Liquid Droplets to Electrostatics in Solution
NASA Astrophysics Data System (ADS)
Yao, Zhenwei
This thesis explores geometric aspects of soft matter systems. The topics covered fall into three categories: (i) geometric frustrations, including the interplay of geometry and topological defects in two dimensional systems, and the frustration of a planar sheet attached to a curved surface; (ii) geometries of liquid droplets, including the curvature driven instabilities of toroidal liquid droplets and the self-propulsion of droplets on a spatially varying surface topography; (iii) the study of the electric double layer structure around charged spherical interfaces by a geometric method. In (i), we study the crystalline order on capillary bridges with varying Gaussian curvature. Energy requires the appearance of topological defects on the surface, which are natural spots for biological activity and chemical functionalization. We further study how liquid crystalline order deforms flexible structured vesicles. In particular we find faceted tetrahedral vesicle as the ground state, which may lead to the design of supra-molecular structures with tetrahedral symmetry and new classes of nano-carriers. Furthermore, by a simple paper model we explore the geometric frustration on a planar sheet when brought to a negative curvature surface in a designed elasto-capillary system. In (ii), motivated by the idea of realizing crystalline order on a stable toroidal droplet and a beautiful experiment on toroidal droplets, we study the Rayleigh instability and the shrinking instability of thin and fat toroidal droplets, where the toroidal geometry plays an essential role. In (iii), by a geometric mapping we construct an approximate analytic spherical solution to the nonlinear Poisson-Boltzmann equation, and identify the applicability regime of the solution. The derived geometric solution enables further analytical study of spherical electrostatic systems such as colloidal suspensions.
Gourkow, Nadine; Phillips, Clive J C
2016-09-01
Acquisition of resources and opportunity to engage in natural behaviors has been shown to reduce frustration-related behaviors and enhance health in nondomestic felids kept in zoos, but little is known about whether there are similar effects in domestic cats living in confinement in animal shelters. Fifteen cats rated as Frustrated during the first hour of confinement to a cage at an animal shelter were assigned to either a Treatment (n=7) or Control (n=8) group. Treatment cats were taken from their cages to a separate room four times daily for 10min each time over a 10 d period, where they took part in training sessions to learn a novel behavior (paw-hand contact with a researcher). Changes in emotional states and mucosal immune response were evaluated over 10days. Infectious status was determined upon admission and incidence of upper respiratory was determined up to day 40 based on clinical signs. Treated cats were more likely to be rated as Content than Control cats and had greater concentrations of S-IgA (537μg/g) in feces than Control cats (101μg/g). Within the Treatment group, cats that responded positively had greater concentrations of S-IgA (925μg/g) than those that responded negatively (399μg/g). Control cats were more likely to develop respiratory disease over time compared to cats that received treatment (Hazard Ratio: 2.37, Confidence Interval: 1.35-4.15). It is concluded that there is prima facie evidence that cognitive enrichment of cats exhibiting frustration-related behaviors can elicit positive affect (contentment), stimulate secretion of IgA and reduce incidence of respiratory disease, which is worthy of further study. Copyright © 2016. Published by Elsevier B.V.
Towards physical principles of biological evolution
NASA Astrophysics Data System (ADS)
Katsnelson, Mikhail I.; Wolf, Yuri I.; Koonin, Eugene V.
2018-03-01
Biological systems reach organizational complexity that far exceeds the complexity of any known inanimate objects. Biological entities undoubtedly obey the laws of quantum physics and statistical mechanics. However, is modern physics sufficient to adequately describe, model and explain the evolution of biological complexity? Detailed parallels have been drawn between statistical thermodynamics and the population-genetic theory of biological evolution. Based on these parallels, we outline new perspectives on biological innovation and major transitions in evolution, and introduce a biological equivalent of thermodynamic potential that reflects the innovation propensity of an evolving population. Deep analogies have been suggested to also exist between the properties of biological entities and processes, and those of frustrated states in physics, such as glasses. Such systems are characterized by frustration whereby local state with minimal free energy conflict with the global minimum, resulting in ‘emergent phenomena’. We extend such analogies by examining frustration-type phenomena, such as conflicts between different levels of selection, in biological evolution. These frustration effects appear to drive the evolution of biological complexity. We further address evolution in multidimensional fitness landscapes from the point of view of percolation theory and suggest that percolation at level above the critical threshold dictates the tree-like evolution of complex organisms. Taken together, these multiple connections between fundamental processes in physics and biology imply that construction of a meaningful physical theory of biological evolution might not be a futile effort. However, it is unrealistic to expect that such a theory can be created in one scoop; if it ever comes to being, this can only happen through integration of multiple physical models of evolutionary processes. Furthermore, the existing framework of theoretical physics is unlikely to suffice for adequate modeling of the biological level of complexity, and new developments within physics itself are likely to be required.
NASA Astrophysics Data System (ADS)
Garcia-Adeva, Angel J.; Huber, David L.
2001-07-01
In this work we generalize and subsequently apply the effective-field renormalization-group (EFRG) technique to the problem of ferro- and antiferromagnetically coupled Ising spins with local anisotropy axes in geometrically frustrated geometries (kagomé and pyrochlore lattices). In this framework, we calculate the various ground states of these systems and the corresponding critical points. Excellent agreement is found with exact and Monte Carlo results. The effects of frustration are discussed. As pointed out by other authors, it turns out that the spin-ice model can be exactly mapped to the standard Ising model, but with effective interactions of the opposite sign to those in the original Hamiltonian. Therefore, the ferromagnetic spin ice is frustrated and does not order. Antiferromagnetic spin ice (in both two and three dimensions) is found to undergo a transition to a long-range-ordered state. The thermal and magnetic critical exponents for this transition are calculated. It is found that the thermal exponent is that of the Ising universality class, whereas the magnetic critical exponent is different, as expected from the fact that the Zeeman term has a different symmetry in these systems. In addition, the recently introduced generalized constant coupling method is also applied to the calculation of the critical points and ground-state configurations. Again, a very good agreement is found with exact, Monte Carlo, and renormalization-group calculations for the critical points. Incidentally, we show that the generalized constant coupling approach can be regarded as the lowest-order limit of the EFRG technique, in which correlations outside a frustrated unit are neglected, and scaling is substituted by strict equality of the thermodynamic quantities.
Teaching and assessing procedural skills: a qualitative study
2013-01-01
Background Graduating Internal Medicine residents must possess sufficient skills to perform a variety of medical procedures. Little is known about resident experiences of acquiring procedural skills proficiency, of practicing these techniques, or of being assessed on their proficiency. The purpose of this study was to qualitatively investigate resident 1) experiences of the acquisition of procedural skills and 2) perceptions of procedural skills assessment methods available to them. Methods Focus groups were conducted in the weeks following an assessment of procedural skills incorporated into an objective structured clinical examination (OSCE). Using fundamental qualitative description, emergent themes were identified and analyzed. Results Residents perceived procedural skills assessment on the OSCE as a useful formative tool for direct observation and immediate feedback. This positive reaction was regularly expressed in conjunction with a frustration with available assessment systems. Participants reported that proficiency was acquired through resident directed learning with no formal mechanism to ensure acquisition or maintenance of skills. Conclusions The acquisition and assessment of procedural skills in Internal Medicine programs should move toward a more structured system of teaching, deliberate practice and objective assessment. We propose that directed, self-guided learning might meet these needs. PMID:23672617
Forgiveness, acceptance and the matter of expectation.
Siassi, Shahrzad
2007-12-01
In this paper, the author argues for a dynamic conceptualization of forgiveness during psychoanalysis. The trauma of failed expectations in intimate relationships is narcissistically dislodging. When legitimate expectations in relationships are not met, forgiveness becomes a challenge for ego to restore the lost narcissistic balance through the resumption of a significant internal bond. The author argues that the ending of any successful analysis is marked by three possibilities regarding the patient's relationship to significant others and his traumas: in cases where the relationship was marked by minimal expectations, one simply learns to accept the wrongdoer without ever feeling the need for forgiveness; in cases where a relationship was marked by high expectations, the patient can learn to accept the trauma without the will or need to forgive its perpetrator. However, even with the painful frustration of high expectations in an intimate relationship, the patient can come to forgive his wrongdoer if there remains enough of a positive internal bond to be salvaged. The developmental roots of such forgiveness, as well as the addictive characteristics of 'nursing a grudge' and the conversion of the qualitative mode of seeking fulfillment into a quantitative one, are further investigated.
Belkaid, Marwen; Cuperlier, Nicolas; Gaussier, Philippe
2017-01-01
Emotions play a significant role in internal regulatory processes. In this paper, we advocate four key ideas. First, novelty detection can be grounded in the sensorimotor experience and allow higher order appraisal. Second, cognitive processes, such as those involved in self-assessment, influence emotional states by eliciting affects like boredom and frustration. Third, emotional processes such as those triggered by self-assessment influence attentional processes. Last, close emotion-cognition interactions implement an efficient feedback loop for the purpose of top-down behavior regulation. The latter is what we call 'Emotional Metacontrol'. We introduce a model based on artificial neural networks. This architecture is used to control a robotic system in a visual search task. The emotional metacontrol intervenes to bias the robot visual attention during active object recognition. Through a behavioral and statistical analysis, we show that this mechanism increases the robot performance and fosters the exploratory behavior to avoid deadlocks.
Vingerhoets, Guy; Sarrechia, Iemke
2009-12-01
Confusion or frustration connected with daily demands involving left-right discrimination is a common observation even in neurologically intact adults. We aimed to test the hypothesis that the degree of left-right confusion is associated with bodily asymmetry. Sixty-two female volunteers performed a left-right decision task that required fast responses to visually presented directional words (left, right, up, down) or pictograms (<--, -->, upward arrow, downward arrow). Participants also performed several tests that measured asymmetry of handedness, grip strength, and tactile sensitivity, and completed self-reports on left-right confusion and perceived bodily asymmetry. Results showed significant correlations between left-right confusion and the degree of handedness and asymmetry in tactile sensitivity. These results suggest that individuals who reveal a stronger internal bias between both sides of the body show less left-right confusion than people with less salient bodily asymmetry.
Psychological needs and the facilitation of integrative processes.
Ryan, R M
1995-09-01
The assumption that there are innate integrative or actualizing tendencies underlying personality and social development is reexamined. Rather than viewing such processes as either nonexistent or as automatic, I argue that they are dynamic and dependent upon social-contextual supports pertaining to basic human psychological needs. To develop this viewpoint, I conceptually link the notion of integrative tendencies to specific developmental processes, namely intrinsic motivation; internalization; and emotional integration. These processes are then shown to be facilitated by conditions that fulfill psychological needs for autonomy, competence, and relatedness, and forestalled within contexts that frustrate these needs. Interactions between psychological needs and contextual supports account, in part, for the domain and situational specificity of motivation, experience, and relative integration. The meaning of psychological needs (vs. wants) is directly considered, as are the relations between concepts of integration and autonomy and those of independence, individualism, efficacy, and cognitive models of "multiple selves."
NASA Astrophysics Data System (ADS)
Zorko, A.; Pregelj, M.; Berger, H.; Arčon, D.
2010-05-01
Local-probe weak-transverse-field and zero-field μSR measurements have been employed to investigate magnetic ordering in the new magnetoelectric compound FeTe2O5Br. Below the Néel transition temperature TN=10.6 K a static local magnetic field starts to develop at the μ+ sites. Fast μ+ polarization decay below TN speaks in favor of a broad distribution of internal magnetic fields, in agreement with the incommensurate magnetic structure suggested by neutron diffraction experiments. Above TN the presence of short-range order is detected as high as at 2TN, which suggests only weak interlayer magnetic coupling. On the other hand, strong Fe3+ spin fluctuations likely reflect geometrically frustrated structure of [Fe4O16]20- spin clusters, which are the main building blocks of the layered FeTe2O5Br structure.
Reconfigurable wave band structure of an artificial square ice
lacocca, Ezio; Gliga, Sebastian; Stamps, Robert L.; ...
2016-04-18
Artificial square ices are structures composed of magnetic nanoelements arranged on the sites of a twodimensional square lattice, such that there are four interacting magnetic elements at each vertex, leading to geometrical frustration. Using a semianalytical approach, we show that square ices exhibit a rich spin-wave band structure that is tunable both by external magnetic fields and the magnetization configuration of individual elements. Internal degrees of freedom can give rise to equilibrium states with bent magnetization at the element edges leading to characteristic excitations; in the presence of magnetostatic interactions these form separate bands analogous to impurity bands in semiconductors.more » Full-scale micromagnetic simulations corroborate our semianalytical approach. Our results show that artificial square ices can be viewed as reconfigurable and tunable magnonic crystals that can be used as metamaterials for spin-wave-based applications at the nanoscale.« less
Reconfigurable wave band structure of an artificial square ice
DOE Office of Scientific and Technical Information (OSTI.GOV)
lacocca, Ezio; Gliga, Sebastian; Stamps, Robert L.
Artificial square ices are structures composed of magnetic nanoelements arranged on the sites of a twodimensional square lattice, such that there are four interacting magnetic elements at each vertex, leading to geometrical frustration. Using a semianalytical approach, we show that square ices exhibit a rich spin-wave band structure that is tunable both by external magnetic fields and the magnetization configuration of individual elements. Internal degrees of freedom can give rise to equilibrium states with bent magnetization at the element edges leading to characteristic excitations; in the presence of magnetostatic interactions these form separate bands analogous to impurity bands in semiconductors.more » Full-scale micromagnetic simulations corroborate our semianalytical approach. Our results show that artificial square ices can be viewed as reconfigurable and tunable magnonic crystals that can be used as metamaterials for spin-wave-based applications at the nanoscale.« less
Littleson, Mairi M; Baker, Christopher M; Dalençon, Anne J; Frye, Elizabeth C; Jamieson, Craig; Kennedy, Alan R; Ling, Kenneth B; McLachlan, Matthew M; Montgomery, Mark G; Russell, Claire J; Watson, Allan J B
2018-03-16
Natural phytotoxins are valuable starting points for agrochemical design. Acting as a jasmonate agonist, coronatine represents an attractive herbicidal lead with novel mode of action, and has been an important synthetic target for agrochemical development. However, both restricted access to quantities of coronatine and a lack of a suitably scalable and flexible synthetic approach to its constituent natural product components, coronafacic and coronamic acids, has frustrated development of this target. Here, we report gram-scale production of coronafacic acid that allows a comprehensive structure-activity relationship study of this target. Biological assessment of a >120 member library combined with computational studies have revealed the key determinants of potency, rationalising hypotheses held for decades, and allowing future rational design of new herbicidal leads based on this template.
Farmer, B.; Bhat, V. S.; Balk, A.; ...
2016-04-25
Here, we have used scanning electron microscopy with polarization analysis and photoemission electron microscopy to image the two-dimensional magnetization of permalloy films patterned into Penrose P2 tilings (P2T). The interplay of exchange interactions in asymmetrically coordinated vertices and short-range dipole interactions among connected film segments stabilize magnetically ordered, spatially distinct sublattices that coexist with frustrated sublattices at room temperature. Numerical simulations that include long-range dipole interactions between sublattices agree with images of as-grown P2T samples and predict a magnetically ordered ground state for a two-dimensional quasicrystal lattice of classical Ising spins.
NASA Astrophysics Data System (ADS)
Ferrari, Francesco; Parola, Alberto; Sorella, Sandro; Becca, Federico
2018-06-01
The dynamical spin structure factor is computed within a variational framework to study the one-dimensional J1-J2 Heisenberg model. Starting from Gutzwiller-projected fermionic wave functions, the low-energy spectrum is constructed from two-spinon excitations. The direct comparison with Lanczos calculations on small clusters demonstrates the excellent description of both gapless and gapped (dimerized) phases, including incommensurate structures for J2/J1>0.5 . Calculations on large clusters show how the intensity evolves when increasing the frustrating ratio and give an unprecedented accurate characterization of the dynamical properties of (nonintegrable) frustrated spin models.
Mapping repulsive to attractive interaction in driven-dissipative quantum systems
NASA Astrophysics Data System (ADS)
Li, Andy C. Y.; Koch, Jens
2017-11-01
Repulsive and attractive interactions usually lead to very different physics. Striking exceptions exist in the dynamics of driven-dissipative quantum systems. For the example of a photonic Bose-Hubbard dimer, we establish a one-to-one mapping relating cases of onsite repulsion and attraction. We prove that the mapping is valid for an entire class of Markovian open quantum systems with a time-reversal-invariant Hamiltonian and physically meaningful inverse-sign Hamiltonian. To underline the broad applicability of the mapping, we illustrate the one-to-one correspondence between the nonequilibrium dynamics in a geometrically frustrated spin lattice and those in a non-frustrated partner lattice.
Backs, Jana; Lange, Merten; Possart, Josephine; Wollschläger, Agnes; Mück-Lichtenfeld, Christian; Uhl, Werner
2017-03-06
An Al/P-based frustrated Lewis pair (FLP) reacted with PhMgCl by an unexpected transmetalation and formation of a phosphinylvinyl Grignard reagent. This compound is well suited for the transfer of the basic FLP component to other Lewis acidic metal atoms and allowed the generation of a Ga/P and an In/P 2 FLP. The Ga FLP showed a behavior different to that of the corresponding Al FLP, the In FLP allowed the chelating coordination of an Au atom by Au-Cl bond activation. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Cooper pair induced frustration and nematicity of two-dimensional magnetic adatom lattices
NASA Astrophysics Data System (ADS)
Schecter, Michael; Syljuâsen, Olav F.; Paaske, Jens
2018-05-01
We propose utilizing the Cooper pair to induce magnetic frustration in systems of two-dimensional (2D) magnetic adatom lattices on s -wave superconducting surfaces. The competition between singlet electron correlations and the RKKY coupling is shown to lead to a variety of hidden-order states that break the point-group symmetry of the 2D adatom lattice at finite temperature. The phase diagram is constructed using a newly developed effective bond theory [M. Schecter et al., Phys. Rev. Lett. 119, 157202 (2017), 10.1103/PhysRevLett.119.157202], and exhibits broad regions of long-range vestigial nematic order.
Graphene nanoFlakes with large spin.
Wang, Wei L; Meng, Sheng; Kaxiras, Efthimios
2008-01-01
We investigate, using benzenoid graph theory and first-principles calculations, the magnetic properties of arbitrarily shaped finite graphene fragments to which we refer as graphene nanoflakes (GNFs). We demonstrate that the spin of a GNF depends on its shape due to topological frustration of the pi-bonds. For example, a zigzag-edged triangular GNF has a nonzero net spin, resembling an artificial ferrimagnetic atom, with the spin value scaling with its linear size. In general, the principle of topological frustration can be used to introduce large net spin and interesting spin distributions in graphene. These results suggest an avenue to nanoscale spintronics through the sculpting of graphene fragments.
H-T Magnetic Phase Diagram of a Frustrated Triangular Lattice Antiferromagnet CuFeO 2
NASA Astrophysics Data System (ADS)
Mitsuda, Setsuo; Mase, Motoshi; Uno, Takahiro; Kitazawa, Hideaki; Katori, Hiroko
2000-01-01
By magnetization and specific heat measurements in an applied magnetic field up to 12 T, we obtained the magnetic field (H) versus temperature (T) phase diagram of a frustrated triangular lattice antiferromagnet (TLA), CuFeO2, where a partially disordered phase typical to Ising TLA exists as a thermally induced state for the 4-sublattice ground state as well as for the first-field-induced 5-sublattice-like state. The experimentally obtained H-T magnetic phase diagram is compared with that from Monte-Carlo simulation of a 2D Ising TLA model with competing exchange interactions up to 3rd neighbors.
Area law violations and quantum phase transitions in modified Motzkin walk spin chains
NASA Astrophysics Data System (ADS)
Sugino, Fumihiko; Padmanabhan, Pramod
2018-01-01
Area law violations for entanglement entropy in the form of a square root have recently been studied for one-dimensional frustration-free quantum systems based on the Motzkin walks and their variations. Here we consider a Motzkin walk with a different Hilbert space on each step of the walk spanned by the elements of a symmetric inverse semigroup with the direction of each step governed by its algebraic structure. This change alters the number of paths allowed in the Motzkin walk and introduces a ground state degeneracy that is sensitive to boundary perturbations. We study the frustration-free spin chains based on three symmetric inverse semigroups, \
Orbital Dimer Model for the Spin-Glass State in Y 2 Mo 2 O 7
Thygesen, Peter M. M.; Paddison, Joseph A. M.; Zhang, Ronghuan; ...
2017-02-08
The formation of a spin glass generally requires that magnetic exchange interactions are both frustrated and disordered. Consequently, the origin of spin-glass behavior in Y 2Mo 2O 7-in which magnetic Mo 4+ ions occupy a frustrated pyrochlore lattice with minimal compositional disorder-has been a longstanding question. Here, we use neutron and x-ray pair-distribution function (PDF) analysis to develop a disorder model that resolves apparent incompatibilities between previously reported PDF, extended x-rayabsorption fine structure spectroscopy, and NMR studies, and provides a new and physical explanation of the exchange disorder responsible for spin-glass formation. We show that Mo 4+ ions displace accordingmore » to a local "two-in-two-out" rule on each Mo 4 tetrahedron, driven by orbital dimerization of Jahn-Teller active Mo 4+ ions. Long-range orbital order is prevented by the macroscopic degeneracy of dimer coverings permitted by the pyrochlore lattice. Cooperative O 2- displacements yield a distribution of Mo-O-Mo angles, which in turn introduces disorder into magnetic interactions. In conclusion, our study demonstrates experimentally how frustration of atomic displacements can assume the role of compositional disorder in driving a spin-glass transition.« less
Spinrad, Tracy L.; Eisenberg, Nancy; Granger, Douglas A.; Eggum, Natalie D.; Sallquist, Julie; Haugen, RG; Kupfer, Anne; Hofer, Claire
2009-01-01
We examined the relations of 84 preschoolers' (43 boys; mean age = 54 months) situational stress reactivity to their observed emotions and mothers' reports of temperament and adjustment. Salivary cortisol and salivary alpha-amylase (sAA) were collected prior to, and following, a frustrating task. Children's anger, sadness, and positive affect were measured, and mothers reported on preschoolers' dispositional emotionality, regulation, impulsivity, and problem behaviors. Forty-seven percent of children had an increase in sAA and 52% had an increase in cortisol following the challenging task. On average, sAA levels showed the predicted pattern of rise following the frustrating task, followed by return to baseline. For cortisol, there was a mean increase from pre-task to 40 minutes post-test. sAA reactivity was associated with relatively low levels of dispositional anger and impulsivity and relatively high regulation, particularly for girls. sAA reactivity also was related to low externalizing problems for girls, but not boys. Although cortisol reactivity was unrelated to children's emotions and maladjustment, it was positively related to mothers' reports of regulation. The findings suggest that sAA reactivity in response to a frustrating social task may reflect girls' constrained behavior. PMID:19348808
Spinrad, Tracy L; Eisenberg, Nancy; Granger, Douglas A; Eggum, Natalie D; Sallquist, Julie; Haugen, R G; Kupfer, Anne; Hofer, Claire
2009-06-01
We examined the relations of 84 preschoolers' (43 boys; mean age=54 months) situational stress reactivity to their observed emotions and mothers' reports of temperament and adjustment. Salivary cortisol and salivary alpha-amylase (sAA) were collected prior to, and following, a frustrating task. Children's anger, sadness, and positive affect were measured, and mothers reported on preschoolers' dispositional emotionality, regulation, impulsivity, and problem behaviors. Forty-seven percent of children had an increase in sAA and 52% had an increase in cortisol following the challenging task. On average, sAA levels showed the predicted pattern of rise following the frustrating task, followed by return to baseline. For cortisol, there was a mean increase from pre-task to 40 min post-test. sAA reactivity was associated with relatively low levels of dispositional anger and impulsivity and relatively high regulation, particularly for girls. sAA reactivity also was related to low externalizing problems for girls, but not boys. Although cortisol reactivity was unrelated to children's emotions and maladjustment, it was positively related to mothers' reports of regulation. The findings suggest that sAA reactivity in response to a frustrating social task may reflect girls' constrained behavior.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thygesen, Peter M. M.; Paddison, Joseph A. M.; Zhang, Ronghuan
The formation of a spin glass generally requires that magnetic exchange interactions are both frustrated and disordered. Consequently, the origin of spin-glass behavior in Y 2Mo 2O 7-in which magnetic Mo 4+ ions occupy a frustrated pyrochlore lattice with minimal compositional disorder-has been a longstanding question. Here, we use neutron and x-ray pair-distribution function (PDF) analysis to develop a disorder model that resolves apparent incompatibilities between previously reported PDF, extended x-rayabsorption fine structure spectroscopy, and NMR studies, and provides a new and physical explanation of the exchange disorder responsible for spin-glass formation. We show that Mo 4+ ions displace accordingmore » to a local "two-in-two-out" rule on each Mo 4 tetrahedron, driven by orbital dimerization of Jahn-Teller active Mo 4+ ions. Long-range orbital order is prevented by the macroscopic degeneracy of dimer coverings permitted by the pyrochlore lattice. Cooperative O 2- displacements yield a distribution of Mo-O-Mo angles, which in turn introduces disorder into magnetic interactions. In conclusion, our study demonstrates experimentally how frustration of atomic displacements can assume the role of compositional disorder in driving a spin-glass transition.« less
Relieving geometrical frustration through doping in the Dy1-x Ca x BaCo4O7 swedenborgites.
Nath Panja, Soumendra; Kumar, Jitender; Dengre, Shanu; Nair, Sunil
2016-12-07
The geometrically frustrated antiferromagnet DyBaCo 4 O 7 is investigated through a combination of x-ray diffraction, magnetization and dielectric measurements. Systematic doping in the series Dy 1-x Ca x BaCo 4 O 7 causes a lifting of the geometrical frustration resulting in a structural transition from a trigonal P31c to an orthorhombic Pbn2 1 symmetry at x = 0.4. This structural transition can also be accessed as a function of temperature, and all our orthorhombic specimens exhibit this transition at elevated temperatures. The temperature at which this structural transition occurs is observed to scale linearly with the mean ionic radius of the R site ion. However, CaBaCo 4 O 7 which has an equal number of Co 2+ and Co 3+ ions clearly violates this quasilinear relationship, indicating that charge ordering could also play a critical role in stabilizing the orthorhombic distortion in this system. Using thermoremanent magnetization measurements to circumvent the problem of the large paramagnetic background arising from Dy 3+ ions, we chart out the phase diagram of the Dy 1-x Ca x BaCo 4 O 7 series.
Barzman, Drew; Eliassen, Jim; McNamara, Robert; Abonia, Pablo; Mossman, Douglas; Durling, Michele; Adler, Caleb; DelBello, Melissa; Lin, Ping-I
2014-11-30
The mechanisms underlying aggression in adolescents with bipolar disorder have been poorly understood. The present study has investigated the associations among TNF gene expressions, functional brain activations under the frustrative non-reward task, and aggression in adolescents with bipolar disorder. Baseline gene expressions and aggressive tendencies were measured with the RNA-sequencing and Brief Rating of Aggression by Children and Adolescents (BRACHA), respectively. Our results show that activity levels of left subgenual anterior cingulate gyrus (ACG), right amygdala, left Brodmann area 10 (orbitofrontal cortex), and right thalamus were inversely correlated with BRACHA scores and were activated with frustrative non-reward during the affective Posner Task. In addition, 11 TNF related gene expressions were significantly correlated with activation of amygdala or ACG during the affective Posner Task. Three TNF gene expressions were inversely correlated with BRACHA score while one TNF gene (TNFAIP3) expression was positively correlated with BRACHA score. Therefore, TNF-related inflammatory cytokine genes may play a role in neural activity associated with frustrative non-reward and aggressive behaviors in pediatric bipolar disorder. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Shahzad, Munir; Sengupta, Pinaki
2017-12-01
We investigate the necessary conditions for the emergence of complex, noncoplanar magnetic configurations in a Kondo lattice model with classical local moments on the geometrically frustrated Shastry-Sutherland lattice and their evolution in an external magnetic field. We demonstrate that topologically nontrivial spin textures, including a new canted flux state, with nonzero scalar chirality arise dynamically from realistic short-range interactions. Our results establish that a finite Dzyaloshinskii-Moriya (DM) interaction is necessary for the emergence of these novel magnetic states when the system is at half filling, for which the ground state is insulating. We identify the minimal set of DM vectors that are necessary for the stabilization of chiral magnetic phases. The noncoplanarity of such structures can be tuned continually by applying an external magnetic field. This is the first part in a series of two papers; in the following paper the effects of frustration, thermal fluctuations, and magnetic field on the emergence of novel noncollinear states at metallic filling of itinerant electrons are discussed. Our results are crucial in understanding the magnetic and electronic properties of the rare-earth tetraboride family of frustrated magnets with separate spin and charge degrees of freedom.
Orbital Dimer Model for the Spin-Glass State in Y_{2}Mo_{2}O_{7}.
Thygesen, Peter M M; Paddison, Joseph A M; Zhang, Ronghuan; Beyer, Kevin A; Chapman, Karena W; Playford, Helen Y; Tucker, Matthew G; Keen, David A; Hayward, Michael A; Goodwin, Andrew L
2017-02-10
The formation of a spin glass generally requires that magnetic exchange interactions are both frustrated and disordered. Consequently, the origin of spin-glass behavior in Y_{2}Mo_{2}O_{7}-in which magnetic Mo^{4+} ions occupy a frustrated pyrochlore lattice with minimal compositional disorder-has been a longstanding question. Here, we use neutron and x-ray pair-distribution function (PDF) analysis to develop a disorder model that resolves apparent incompatibilities between previously reported PDF, extended x-ray-absorption fine structure spectroscopy, and NMR studies, and provides a new and physical explanation of the exchange disorder responsible for spin-glass formation. We show that Mo^{4+} ions displace according to a local "two-in-two-out" rule on each Mo_{4} tetrahedron, driven by orbital dimerization of Jahn-Teller active Mo^{4+} ions. Long-range orbital order is prevented by the macroscopic degeneracy of dimer coverings permitted by the pyrochlore lattice. Cooperative O^{2-} displacements yield a distribution of Mo-O-Mo angles, which in turn introduces disorder into magnetic interactions. Our study demonstrates experimentally how frustration of atomic displacements can assume the role of compositional disorder in driving a spin-glass transition.
Transition to synchrony in degree-frequency correlated Sakaguchi-Kuramoto model
NASA Astrophysics Data System (ADS)
Kundu, Prosenjit; Khanra, Pitambar; Hens, Chittaranjan; Pal, Pinaki
2017-11-01
We investigate transition to synchrony in degree-frequency correlated Sakaguchi-Kuramoto (SK) model on complex networks both analytically and numerically. We analytically derive self-consistent equations for group angular velocity and order parameter for the model in the thermodynamic limit. Using the self-consistent equations we investigate transition to synchronization in SK model on uncorrelated scale-free (SF) and Erdős-Rényi (ER) networks in detail. Depending on the degree distribution exponent (γ ) of SF networks and phase-frustration parameter, the population undergoes from first-order transition [explosive synchronization (ES)] to second-order transition and vice versa. In ER networks transition is always second order irrespective of the values of the phase-lag parameter. We observe that the critical coupling strength for the onset of synchronization is decreased by phase-frustration parameter in case of SF network where as in ER network, the phase-frustration delays the onset of synchronization. Extensive numerical simulations using SF and ER networks are performed to validate the analytical results. An analytical expression of critical coupling strength for the onset of synchronization is also derived from the self-consistent equations considering the vanishing order parameter limit.
Comment on ‘Oxygen vacancy-induced magnetic moment in edge-sharing CuO2 chains of Li2CuO2’
NASA Astrophysics Data System (ADS)
Kuzian, R. O.; Klingeler, R.; Lorenz, W. E. A.; Wizent, N.; Nishimoto, S.; Nitzsche, U.; Rosner, H.; Milosavljevic, D.; Hozoi, L.; Yadav, R.; Richter, J.; Hauser, A.; Geck, J.; Hayn, R.; Yushankhai, V.; Siurakshina, L.; Monney, C.; Schmitt, T.; Thar, J.; Roth, G.; Ito, T.; Yamaguchi, H.; Matsuda, M.; Johnston, S.; Málek, J.; Drechsler, S.-L.
2018-05-01
In a recent work devoted to the magnetism of Li2CuO2, Shu et al (2017 New J. Phys. 19, 023026) have proposed a ‘simplified’ unfrustrated microscopic model that differs considerably from the models refined through decades of prior work. We show that the proposed model is at odds with known experimental data, including the reported magnetic susceptibility χ(T) data up to 550 K. Using an 8th order high-temperature expansion for χ(T), we show that the experimental data for Li2CuO2 are consistent with the prior model derived from inelastic neutron scattering studies. We also establish the T-range of validity for a Curie–Weiss law for the real frustrated magnetic system. We argue that the knowledge of the long-range ordered magnetic structure for T < T N and of χ(T) in a restricted T-range provides insufficient information to extract all of the relevant couplings in frustrated magnets; the saturation field and INS data must also be used to determine several exchange couplings, including the weak but decisive frustrating antiferromagnetic interchain couplings.
Quantum Spin Liquids in Frustrated Spin-1 Diamond Antiferromagnets
NASA Astrophysics Data System (ADS)
Buessen, Finn Lasse; Hering, Max; Reuther, Johannes; Trebst, Simon
2018-01-01
Motivated by the recent synthesis of the spin-1 A -site spinel NiRh2 O4 , we investigate the classical to quantum crossover of a frustrated J1-J2 Heisenberg model on the diamond lattice upon varying the spin length S . Applying a recently developed pseudospin functional renormalization group approach for arbitrary spin-S magnets, we find that systems with S ≥3 /2 reside in the classical regime, where the low-temperature physics is dominated by the formation of coplanar spirals and a thermal (order-by-disorder) transition. For smaller local moments S =1 or S =1 /2 , we find that the system evades a thermal ordering transition and forms a quantum spiral spin liquid where the fluctuations are restricted to characteristic momentum-space surfaces. For the tetragonal phase of NiRh2 O4 , a modified J1-J2--J2⊥ exchange model is found to favor a conventionally ordered Néel state (for arbitrary spin S ), even in the presence of a strong local single-ion spin anisotropy, and it requires additional sources of frustration to explain the experimentally observed absence of a thermal ordering transition.
Competing Spin Liquids and Hidden Spin-Nematic Order in Spin Ice with Frustrated Transverse Exchange
NASA Astrophysics Data System (ADS)
Taillefumier, Mathieu; Benton, Owen; Yan, Han; Jaubert, L. D. C.; Shannon, Nic
2017-10-01
Frustration in magnetic interactions can give rise to disordered ground states with subtle and beautiful properties. The spin ices Ho2 Ti2 O7 and Dy2 Ti2 O7 exemplify this phenomenon, displaying a classical spin-liquid state, with fractionalized magnetic-monopole excitations. Recently, there has been great interest in closely related "quantum spin-ice" materials, following the realization that anisotropic exchange interactions could convert spin ice into a massively entangled, quantum spin liquid, where magnetic monopoles become the charges of an emergent quantum electrodynamics. Here we show that even the simplest model of a quantum spin ice, the XXZ model on the pyrochlore lattice, can realize a still-richer scenario. Using a combination of classical Monte Carlo simulation, semiclassical molecular-dynamics simulation, and analytic field theory, we explore the properties of this model for frustrated transverse exchange. We find not one, but three competing forms of spin liquid, as well as a phase with hidden, spin-nematic order. We explore the experimental signatures of each of these different states, making explicit predictions for inelastic neutron scattering. These results show an intriguing similarity to experiments on a range of pyrochlore oxides.
Weinkam, Patrick; Romesberg, Floyd E.; Wolynes, Peter G.
2010-01-01
A grand canonical formalism is developed to combine discrete simulations for chemically distinct species in equilibrium. Each simulation is based on a perturbed funneled landscape. The formalism is illustrated using the alkaline-induced transitions of cytochrome c as observed by FTIR spectroscopy and with various other experimental approaches. The grand canonical simulation method accounts for the acid/base chemistry of deprotonation, the inorganic chemistry of heme ligation and misligation, and the minimally frustrated folding energy landscape, thus elucidating the physics of protein folding involved with an acid/base titration of a protein. The formalism combines simulations for each of the relevant chemical species, varying by protonation and ligation states. In contrast to models based on perfectly funneled energy landscapes that contain only contacts found in the native structure, the current study introduces “chemical frustration” from deprotonation and misligation that gives rise to many intermediates at alkaline pH. While the nature of these intermediates cannot be easily inferred from available experimental data, the current study provides specific structural details of these intermediates thus extending our understanding of how cytochrome c changes with increasing pH. The results demonstrate the importance of chemical frustration for understanding biomolecular energy landscapes. PMID:19199810
Doping effects on the relaxation of frustration and magnetic properties of YMn0.9Cu0.1O3
NASA Astrophysics Data System (ADS)
Xiao, L. X.; Xia, Z. C.; Wang, X.; Ni, Y.; Yu, W.; Shi, L. R.; Jin, Z.; Xiao, G. L.
2017-12-01
The crystal structure and magnetic properties of hexagonal YMn0.9Cu0.1O3 single crystal are systematically investigated. The refinement results of XRD show the lattice constant decreases, which is unusually due to the doped Cu2+ ion has a larger ionic radius than the Mn3+ ions. The XPS results show that the coexistence of Mn2+, Mn3+ and Mn4+ ions in YMn0.9Cu0.1O3 single crystal. Magnetization measurements show that Cu doped YMn0.9Cu0.1O3 and parent YMnO3 have almost the same antiferromagnetic transition temperature TN, which indicates the AFM interaction is robust in the geometry frustrated system. Because doping directly destroy some of the Mn3+ ions nets, the relaxation of frustration of Mn in-plane 2D triangular geometry network leads to the significantly decrease of Mn3+ ions AFM interaction. In addition, the coexistence and competition between the ferromagnetic and antiferromagnetic interactions among the Mn2+, Mn3+ and Mn4+ ions lead to a complicated and irreversible magnetization behavior in YMn0.9Cu0.1O3 single crystal.
Atomic displacements in the charge ice pyrochlore Bi2Ti2O6O' studied by neutron total scattering
NASA Astrophysics Data System (ADS)
Shoemaker, Daniel P.; Seshadri, Ram; Hector, Andrew L.; Llobet, Anna; Proffen, Thomas; Fennie, Craig J.
2010-04-01
The oxide pyrochlore Bi2Ti2O6O' is known to be associated with large displacements of Bi and O' atoms from their ideal crystallographic positions. Neutron total scattering, analyzed in both reciprocal and real space, is employed here to understand the nature of these displacements. Rietveld analysis and maximum entropy methods are used to produce an average picture of the structural nonideality. Local structure is modeled via large-box reverse Monte Carlo simulations constrained simultaneously by the Bragg profile and real-space pair distribution function. Direct visualization and statistical analyses of these models show the precise nature of the static Bi and O' displacements. Correlations between neighboring Bi displacements are analyzed using coordinates from the large-box simulations. The framework of continuous symmetry measures has been applied to distributions of O'Bi4 tetrahedra to examine deviations from ideality. Bi displacements from ideal positions appear correlated over local length scales. The results are consistent with the idea that these nonmagnetic lone-pair containing pyrochlore compounds can be regarded as highly structurally frustrated systems.