Experimental investigation of the no-signalling principle in parity-time symmetric theory using an open quantum system

NASA Astrophysics Data System (ADS)

Tang, Jian-Shun; Wang, Yi-Tao; Yu, Shang; He, De-Yong; Xu, Jin-Shi; Liu, Bi-Heng; Chen, Geng; Sun, Yong-Nan; Sun, Kai; Han, Yong-Jian; Li, Chuan-Feng; Guo, Guang-Can

2016-10-01

The experimental progress achieved in parity-time () symmetry in classical optics is the most important accomplishment in the past decade and stimulates many new applications, such as unidirectional light transport and single-mode lasers. However, in the quantum regime, some controversial effects are proposed for -symmetric theory, for example, the potential violation of the no-signalling principle. It is therefore important to understand whether -symmetric theory is consistent with well-established principles. Here, we experimentally study this no-signalling problem related to the -symmetric theory using two space-like separated entangled photons, with one of them passing through a post-selected quantum gate, which effectively simulates a -symmetric evolution. Our results suggest that the superluminal information transmission can be simulated when the successfully -symmetrically evolved subspace is solely considered. However, considering this subspace is only a part of the full Hermitian system, additional information regarding whether the -symmetric evolution is successful is necessary, which transmits to the receiver at maximally light speed, maintaining the no-signalling principle.

Experimental investigation of the no-signalling principle in parity-time symmetric theory using an open quantum system

NASA Astrophysics Data System (ADS)

Tang, Jian-Shun; Wang, Yi-Tao; Han, Yong-Jian; Li, Chuan-Feng; Guo, Guang-Can

The experimental progress achieved in parity-time (PT) symmetry in classical optics is the most important accomplishment in the past decade and stimulates many new applications, such as unidirectional light transport and single-mode lasers. However, in the quantum regime, some controversial effects are proposed for PT-symmetric theory, for example, the potential violation of the no-signalling principle. It is therefore important to understand whether PT-symmetric theory is consistent with well-established principles. Here, we experimentally study this no-signalling problem related to the PT-symmetric theory using two space-like separated entangled photons, with one of them passing through a post-selected quantum gate, which effectively simulates a PT-symmetric evolution. Our results suggest that the superluminal information transmission can be simulated when the successfully PT-symmetrically evolved subspace is solely considered. However, considering this subspace is only a part of the full Hermitian system, additional information regarding whether the PT-symmetric evolution is successful is necessary, which transmits to the receiver at maximally light speed, maintaining the no-signalling principle.

The Utilization of the Seven Principles for Good Practices of Full-Time and Adjunct Faculty in Teaching Health & Science in Community Colleges

ERIC Educational Resources Information Center

Musaitif, Linda M.

2013-01-01

Purpose: The purpose of this study was to determine the degree to which undergraduate full-time and adjunct faculty members in the health and science programs at community colleges in Southern California utilize the seven principles of good practice as measured by the Faculty Inventory of the Seven Principles for Good Practice in Undergraduate…

Charge-density-shear-moduli relationships in aluminum-lithium alloys.

PubMed

Eberhart, M

2001-11-12

Using the first principles full-potential linear-augmented-Slater-type orbital technique, the energies and charge densities of aluminum and aluminum-lithium supercells have been computed. The experimentally observed increase in aluminum's shear moduli upon alloying with lithium is argued to be the result of predictable changes to aluminum's total charge density, suggesting that simple rules may allow the alloy designer to predict the effects of dilute substitutional elements on alloy elastic response.

Spectral imaging: principles and applications.

PubMed

Garini, Yuval; Young, Ian T; McNamara, George

2006-08-01

Spectral imaging extends the capabilities of biological and clinical studies to simultaneously study multiple features such as organelles and proteins qualitatively and quantitatively. Spectral imaging combines two well-known scientific methodologies, namely spectroscopy and imaging, to provide a new advantageous tool. The need to measure the spectrum at each point of the image requires combining dispersive optics with the more common imaging equipment, and introduces constrains as well. The principles of spectral imaging and a few representative applications are described. Spectral imaging analysis is necessary because the complex data structure cannot be analyzed visually. A few of the algorithms are discussed with emphasis on the usage for different experimental modes (fluorescence and bright field). Finally, spectral imaging, like any method, should be evaluated in light of its advantages to specific applications, a selection of which is described. Spectral imaging is a relatively new technique and its full potential is yet to be exploited. Nevertheless, several applications have already shown its potential. (c) 2006 International Society for Analytical Cytology.

First-principles investigation for some physical properties of some fluoroperovskites compounds ABF3 (A = K, Na; B = Mg, Zn)

NASA Astrophysics Data System (ADS)

Bakri, Badis; Driss, Zied; Berri, Saadi; Khenata, Rabah

2017-12-01

In this work, the structural, electronic and optical properties of fluoroperovskite ABF3 (A = K, Na; B = Mg, Zn) were studied using two different approaches: the full-potential linearized augmented plane wave method and the pseudo-potential plane wave scheme in the frame of generalized gradient approximation features such as the lattice constant, bulk modulus and its pressure derivative are reported. The ground state properties of these compounds such as the equilibrium lattice constant and the bulk modulus are in good agreement with the experimental results. The first principles calculations were performed to study the electronic structures of ABF3(A = K, Na; B = Mg, Zn) compounds and the results indicated that these four compounds are indirect band gap insulators. The optical properties are analysed and the source of some peaks in the spectra is discussed. Besides, the dielectric function, refractive index and extinction coefficient for radiation up to 25 eV have also been reported and discussed.

"We need our own food, to grow our own veggies…" Remote Aboriginal food gardens in the Top End of Australia's Northern Territory.

PubMed

Hume, Andrew; O'Dea, Kerin; Brimblecombe, Julie

2013-10-01

Remote Aboriginal community gardens (gardens) frequently operate below their full potential. A set of gardening sustainability principles may improve their planning, operation and long-term sustainability. This paper aims to document the principles of sustainability of non-profit remote Aboriginal community gardens in the Top End of the Northern Territory. Throughout 2011, gardens in the Top End of the Northern Territory were visited. Interviews and observational data were used to explore the principles of garden sustainability with participants. Subsequent iterative thematic analysis informed development of a set of gardening sustainability principles. Principles of sustainability included effective garden planning; community autonomy, consultation and engagement; growing community vetted crops; employing long-term, effective, culturally sensitive managers; long-term, transparent funding organisations and cycles; garden integration into existing food supply chains; culturally appropriate employment arrangements; and physical aspects of successful gardening. This work uniquely consults gardeners, managers and Aboriginal and non-Aboriginal people of both genders in the largest reported study of its type, resulting in new and expanded findings, particularly including new social factors for gardening success. Expanding the understanding of what makes gardens work to include the important social factors identified here may have merit. © 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.

Proton transfer from water to ketyl radical anion: Assessment of critical size of hydrated cluster and free energy barrier in solution from first principles simulations

NASA Astrophysics Data System (ADS)

Biswas, Sohag; Dasgupta, Teesta; Mallik, Bhabani S.

2016-09-01

We present the reactivity of an organic intermediate by studying the proton transfer process from water to ketyl radical anion using gas phase electronic structure calculations and the metadynamics method based first principles molecular dynamics (FPMD) simulations. Our results indicate that during the micro solvation of anion by water molecules systematically, the presence of minimum three water molecules in the gas phase cluster is sufficient to observe the proton transfer event. The analysis of trajectories obtained from initial FPMD simulation of an aqueous solution of the anion does not show any evident of complete transfer of the proton from water. The cooperativity of water molecules and the relatively weak anion-water interaction in liquid state prohibit the full release of the proton. Using biasing potential through first principles metadynamics simulations, we report the observation of proton transfer reaction from water to ketyl radical anion with a barrier height of 16.0 kJ/mol.

12 CFR 615.5230 - Implementation of cooperative principles.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Implementation of cooperative principles. 615... Implementation of cooperative principles. (a) Voting shareholders of Farm Credit banks and associations shall be accorded full voting rights in accordance with cooperative principles. (1) Each voting shareholder of an...

Use of an approximate similarity principle for the thermal scaling of a full-scale thrust augmenting ejector

NASA Technical Reports Server (NTRS)

Barankiewicz, Wendy S.; Perusek, Gail P.; Ibrahim, Mounir B.

1992-01-01

Full temperature ejector model simulations are expensive, and difficult to implement experimentally. If an approximate similarity principle could be established, properly chosen performance parameters should be similar for both hot and cold flow tests if the initial Mach number and total pressures of the flow field are held constant. Existing ejector data is used to explore the utility of one particular similarity principle; the Munk and Prim similarity principle for isentropic flows. Static performance test data for a full-scale thrust augmenting ejector are analyzed for primary flow temperatures up to 1560 R. At different primary temperatures, exit pressure contours are compared for similarity. A nondimensional flow parameter is then used to eliminate primary nozzle temperature dependence and verify similarity between the hot and cold flow experiments.

Use of an approximate similarity principle for the thermal scaling of a full-scale thrust augmenting ejector

NASA Technical Reports Server (NTRS)

Barankiewicz, Wendy; Perusek, Gail P.; Ibrahim, Mounir

1992-01-01

Full temperature ejector model simulations are expensive, and difficult to implement experimentally. If an approximate similarity principle could be established, properly chosen performance parameters should be similar for both hot and cold flow tests if the initial Mach number and total pressures of the flow field are held constant. Existing ejector data is used to explore the utility of one particular similarity principle; the Munk and Prim similarity principle for isentropic flows. Static performance test data for a full-scale thrust augmenting ejector are analyzed for primary flow temperatures up to 1560 R. At different primary temperatures, exit pressure contours are compared for similarity. A nondimensional flow paramenter is then used to eliminate primary nozzle temperature dependence and verify similarity between the hot and cold flow experiments.

First principles predictions of electronic and elastic properties of BaPb2As2 in the ThCr2Si2-type structure

NASA Astrophysics Data System (ADS)

Bourourou, Y.; Amari, S.; Yahiaoui, I. E.; Bouhafs, B.

2018-01-01

A first-principles approach is used to predicts the electronic and elastic properties of BaPb2As2 superconductor compound, using full-potential linearized augmented plane wave plus local orbitals (FP-L/APW+lo) scheme within the local density approximation LDA. The calculated equilibrium structural parameter a agree well with the experiment while the c/a ratio is far away from the experimental result. The band structure, density of states, together with the charge density and chemical bonding are discussed. The calculated elastic constants for our compound indicate that it is mechanically stable at ambient pressure. Polycrystalline elastic moduli (Young's, Bulk, shear Modulus and the Poisson's ratio) were calculated according to the Voigte-Reusse-Hill (VRH) average.

Police Reforms: Identifying The Potential Adverse Impacts And Challenges To Law Enforcement Agencies

DTIC Science & Technology

2017-12-01

their full impact on law enforcement agencies will be known in the coming years not months. The following chapter features three case studies ...and the PERF Guiding Principles. These case studies consider the impacts on agency outputs in terms of proactive officer activity along with some...reforms adopted through NYPD policy and legislative action on the part of the New York City Council. The purpose of these case studies is to

Computational investigations of the band structure, and thermodynamic and optical features of thorium-based oxide ThGeO4 using the full-potential linearized augmented plane-wave plus local orbital approach

NASA Astrophysics Data System (ADS)

Chiker, F.; Khachai, H.; Mathieu, C.; Bin-Omran, S.; Kada, Belkacem; Sun, Xiao-Wei; Sandeep; Rai, D. P.; Khenata, R.

2018-05-01

In this study, first-principles investigations were performed using the full-potential linearized augmented plane-wave method of the structural and optoelectronic properties of thorium germinate (ThGeO4), a high-K dielectric material. Under ambient conditions, the structural properties calculated for ThGeO4 in the zircon phase were in excellent agreement with the available experimental data. Furthermore, using the modified Becke -Johnson correction method, the calculated band gaps and optical constants accurately described this compound. Finally, the thermal properties were predicted over a temperature range of 0-700 K and pressures up to 11 GPa using the quasi-harmonic Debye model, where the variations in the heat capacity, primitive cell volume, and thermal expansion coefficients were determined successfully.

First-principles interatomic potentials for transition-metal aluminides. III. Extension to ternary phase diagrams

NASA Astrophysics Data System (ADS)

Widom, Mike; Al-Lehyani, Ibrahim; Moriarty, John A.

2000-08-01

Modeling structural and mechanical properties of intermetallic compounds and alloys requires detailed knowledge of their interatomic interactions. The first two papers of this series [Phys. Rev. B 56, 7905 (1997); 58, 8967 (1998)] derived first-principles interatomic potentials for transition-metal (TM) aluminides using generalized pseudopotential theory (GPT). Those papers focused on binary alloys of aluminum with first-row transition metals and assessed the ability of GPT potentials to reproduce and elucidate the alloy phase diagrams of Al-Co and Al-Ni. This paper addresses the phase diagrams of the binary alloy Al-Cu and the ternary systems Al-Co-Cu and Al-Co-Ni, using GPT pair potentials calculated in the limit of vanishing transition-metal concentration. Despite this highly simplifying approximation, we find rough agreement with the known low-temperature phase diagrams, up to 50% total TM concentration provided the Co fraction is below 25%. Full composition-dependent potentials and many-body interactions would be required to correct deficiencies at higher Co concentration. Outside this troublesome region, the experimentally determined stable and metastable phases all lie on or near the convex hull of a scatter plot of energy versus composition. We verify, qualitatively, reported solubility ranges extending binary alloys into the ternary diagram in both Al-Co-Cu and Al-Co-Ni. Finally, we reproduce previously conjectured transition-metal positions in the decagonal quasicrystal phase.

High-Level, First-Principles, Full-Dimensional Quantum Calculation of the Ro-vibrational Spectrum of the Simplest Criegee Intermediate (CH2OO).

PubMed

Li, Jun; Carter, Stuart; Bowman, Joel M; Dawes, Richard; Xie, Daiqian; Guo, Hua

2014-07-03

The ro-vibrational spectrum of the simplest Criegee intermediate (CH2OO) has been determined quantum mechanically based on nine-dimensional potential energy and dipole surfaces for its ground electronic state. The potential energy surface is fitted to more than 50 000 high-level ab initio points with a root-mean-square error of 25 cm(-1), using a recently proposed permutation invariant polynomial neural network method. The calculated rotational constants, vibrational frequencies, and spectral intensities of CH2OO are in excellent agreement with experiment. The potential energy surface provides a valuable platform for studying highly excited vibrational and unimolecular reaction dynamics of this important molecule.

Role of modified Becke-Johnson potential in computation of electronic and optical properties of mixed crystals CdxZn1-xSe

NASA Astrophysics Data System (ADS)

Talreja, Sonal; Ahuja, B. L.

2015-08-01

Electronic and optical properties of CdxZn1-xSe (x = 0, 0.25, 0.5, 0.75, 1) compounds are investigated using the first-principles full potential linearized augmented plane wave method. In particular, we have used modified version of the exchange potential of Becke and Johnson, so called mBJ potential. We have discussed the energy bands, density of states, and optical properties such as dielectric constants, refractive indices, reflection spectra, extinction coefficients of all the CdxZn1-xSe compounds. Our mBJ potential based data are found to be in excellent agreement with the available experimental data, which unambiguously validates the applicability of orbital independent exchange-correlation potential in mixed semiconductor crystals. The optical properties are discussed in terms of applicability of Cd-Zn-Se system in light-emitting diodes, UV detectors and filters, etc.

A Lack of Continuity in Education, Training, and Practice Violates the "Do No Harm" Principle.

PubMed

Englander, Robert; Carraccio, Carol

2018-03-01

The paradigm shift to competency-based medical education (CBME) is under way, but incomplete implementation is blunting the potential impact on learning and patient outcomes. The fundamental principles of CBME call for standardizing outcomes addressing population health needs, then allowing time-variable progression to achieving them. Operationalizing CBME principles requires continuity within and across phases of the education, training, and practice continuum. However, the piecemeal origin of the phases of the "continuum" has resulted in a sequence of undergraduate to graduate medical education to practice that may be continuous temporally but bears none of the integration of a true continuum.With these timed interruptions during phase transitions, learning is not reinforced because of a failure to integrate experiences. Brief block rotations for learners and ever-shorter supervisory assignments for faculty preclude the development of relationships. Without these relationships, feedback falls on deaf ears. Block rotations also disrupt learners' relationships with patients. The harms resulting from such a system include decreases in patient satisfaction with their care and learner satisfaction with their work. Learners in this block system also demonstrate an erosion of empathy compared with those in innovative longitudinal training models. In addition, higher patient mortality during intern transitions has been demonstrated.The current medical education system is violating the first principle of medicine: "Do no harm." Full implementation of competency-based, time-variable education and training, with fixed outcomes aligned with population health needs, continuity in learning and relationships, and support from a developmental program of assessment, holds great potential to stop this harm.

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

Verma, U. P.; Nayak, V.

Quantum mechanical first principle calculations have been performed to study the electronic and structural properties of TiN and TiAs in zinc blende (ZB) and rock salt (RS) structures. The full-potential linearized augmented plane wave (FP-LAPW) method has been used within the framework of density functional theory (DFT). The exchange correlation functional has been solved employing generalized gradient approximation (GGA). Our predicted results for lattice constants are in good agreement with the earlier findings. The electronic band structures of TiX are metallic in both the phases.

Making sound vortices by metasurfaces

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

Ye, Liping; Qiu, Chunyin, E-mail: cyqiu@whu.edu.cn; Lu, Jiuyang

Based on the Huygens-Fresnel principle, a metasurface structure is designed to generate a sound vortex beam in airborne environment. The metasurface is constructed by a thin planar plate perforated with a circular array of deep subwavelength resonators with desired phase and amplitude responses. The metasurface approach in making sound vortices is validated well by full-wave simulations and experimental measurements. Potential applications of such artificial spiral beams can be anticipated, as exemplified experimentally by the torque effect exerting on an absorbing disk.

Making sound vortices by metasurfaces

NASA Astrophysics Data System (ADS)

Ye, Liping; Qiu, Chunyin; Lu, Jiuyang; Tang, Kun; Jia, Han; Ke, Manzhu; Peng, Shasha; Liu, Zhengyou

2016-08-01

Based on the Huygens-Fresnel principle, a metasurface structure is designed to generate a sound vortex beam in airborne environment. The metasurface is constructed by a thin planar plate perforated with a circular array of deep subwavelength resonators with desired phase and amplitude responses. The metasurface approach in making sound vortices is validated well by full-wave simulations and experimental measurements. Potential applications of such artificial spiral beams can be anticipated, as exemplified experimentally by the torque effect exerting on an absorbing disk.

Bimolecular reaction dynamics from photoelectron spectroscopy of negative ions

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

Bradforth, S.E.

1992-11-01

The transition state region of a neutral bimolecular reaction may be experimentally investigated by photoelectron spectroscopy of an appropriate negative ion. The photoelectron spectrum provides information on the spectroscopy and dynamics of the short lived transition state and may be used to develop model potential energy surfaces that are semi-quantitative in this important region. The principles of bound [yields] bound negative ion photoelectron spectroscopy are illustrated by way of an example: a full analysis of the photoelectron bands of CN[sup [minus

First-principles quantum dynamical theory for the dissociative chemisorption of H2O on rigid Cu(111)

PubMed Central

Zhang, Zhaojun; Liu, Tianhui; Fu, Bina; Yang, Xueming; Zhang, Dong H.

2016-01-01

Despite significant progress made in the past decades, it remains extremely challenging to investigate the dissociative chemisorption dynamics of molecular species on surfaces at a full-dimensional quantum mechanical level, in particular for polyatomic-surface reactions. Here we report, to the best of our knowledge, the first full-dimensional quantum dynamics study for the dissociative chemisorption of H2O on rigid Cu(111) with all the nine molecular degrees of freedom fully coupled, based on an accurate full-dimensional potential energy surface. The full-dimensional quantum mechanical reactivity provides the dynamics features with the highest accuracy, revealing that the excitations in vibrational modes of H2O are more efficacious than increasing the translational energy in promoting the reaction. The enhancement of the excitation in asymmetric stretch is the largest, but that of symmetric stretch becomes comparable at very low energies. The full-dimensional characterization also allows the investigation of the validity of previous reduced-dimensional and approximate dynamical models. PMID:27283908

Grand Canonical adaptive resolution simulation for molecules with electrons: A theoretical framework based on physical consistency

NASA Astrophysics Data System (ADS)

Delle Site, Luigi

2018-01-01

A theoretical scheme for the treatment of an open molecular system with electrons and nuclei is proposed. The idea is based on the Grand Canonical description of a quantum region embedded in a classical reservoir of molecules. Electronic properties of the quantum region are calculated at constant electronic chemical potential equal to that of the corresponding (large) bulk system treated at full quantum level. Instead, the exchange of molecules between the quantum region and the classical environment occurs at the chemical potential of the macroscopic thermodynamic conditions. The Grand Canonical Adaptive Resolution Scheme is proposed for the treatment of the classical environment; such an approach can treat the exchange of molecules according to first principles of statistical mechanics and thermodynamic. The overall scheme is build on the basis of physical consistency, with the corresponding definition of numerical criteria of control of the approximations implied by the coupling. Given the wide range of expertise required, this work has the intention of providing guiding principles for the construction of a well founded computational protocol for actual multiscale simulations from the electronic to the mesoscopic scale.

First-principles calculations of two cubic fluoropervskite compounds: RbFeF3 and RbNiF3

NASA Astrophysics Data System (ADS)

Mubarak, A. A.; Al-Omari, Saleh

2015-05-01

We present first-principles calculations of the structural, elastic, electronic, magnetic and optical properties for RbFeF3 and RbNiF3. The full-potential linear augmented plan wave (FP-LAPW) method within the density functional theory was utilized to perform the present calculations. We employed the generalized gradient approximation as exchange-correlation potential. It was found that the calculated analytical lattice parameters agree with previous studies. The analysis of elastic constants showed that the present compounds are elastically stable and anisotropic. Moreover, both compounds are classified as a ductile compound. The calculations of the band structure and density functional theory revealed that the RbFeF3 compound has a half-metallic behavior while the RbNiF3 compound has a semiconductor behavior with indirect (M-Γ) band gap. The ferromagnetic behavior was studied for both compounds. The optical properties were calculated for the radiation of up to 40 eV. A beneficial optics technology is predicted as revealed from the optical spectra.

Network Medicine for Alzheimer's Disease and Traditional Chinese Medicine.

PubMed

Jarrell, Juliet T; Gao, Li; Cohen, David S; Huang, Xudong

2018-05-11

Alzheimer’s Disease (AD) is a neurodegenerative condition that currently has no known cure. The principles of the expanding field of network medicine (NM) have recently been applied to AD research. The main principle of NM proposes that diseases are much more complicated than one mutation in one gene, and incorporate different genes, connections between genes, and pathways that may include multiple diseases to create full scale disease networks. AD research findings as a result of the application of NM principles have suggested that functional network connectivity, myelination, myeloid cells, and genes and pathways may play an integral role in AD progression, and may be integral to the search for a cure. Different aspects of the AD pathology could be potential targets for drug therapy to slow down or stop the disease from advancing, but more research is needed to reach definitive conclusions. Additionally, the holistic approaches of network pharmacology in traditional Chinese medicine (TCM) research may be viable options for the AD treatment, and may lead to an effective cure for AD in the future.

Relief from anxiety using complementary therapies in the perioperative period: A principle-based concept analysis.

PubMed

Jaruzel, Candace B; Kelechi, Teresa J

2016-08-01

To analyze and clarify the concept of providing relief from anxiety using complementary therapies in the perioperative period utilizing the epistemological, pragmatic, linguistic and logical principles of a principle-based concept analysis to examine the state of the science. The majority of patients scheduled for surgery experience anxiety in the perioperative period. Anxiety has the potential to limit a patient's ability to participate in his or her care throughout their hospitalization. Although medications are the conventional medical treatment for anxiety in the perioperative period, the addition of a complementary therapy could be an effective holistic approach to providing relief from anxiety. Principle-based concept analysis. In 2015, strategic literature searches of CINHAL and PUBMED using keywords were performed. Fifty-six full text articles were assessed for eligibility. Twelve studies were used in the final analysis to clarify the concept of relief from anxiety using complementary therapies in the perioperative period. This analysis has clarified the maturity and boundaries, within the four principles of a principle-based concept analysis, of the concept of relief from anxiety using complementary therapies in the perioperative period. A greater understanding of relief from anxiety using complimentary therapies in the perioperative period as an adjunct to conventional medicine will allow perioperative nurses and anesthesia providers to modify and specify the plan of care for their surgical patients. The use of complementary therapies for relief in the perioperative period appears to be an area of promising research and treatment for patients, families and providers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cost Reporting at a Navy Branch Clinic

DTIC Science & Technology

1993-03-01

John Wiley & Sons, 1991. 15 Horngren , Charles, Cost Accounting -=A Managerial Emphasis, 5th Edition, Prentice Hall, Inc., Englewood Cliffs, N.J., 1982...traditionally reported under a partial cost reporting system. By applying basic principles of managerial accounting , a full cost reporting system is...traditionally reported under a partial cost reporting system. By applying basic principles of managerial accounting , a proposed full cost reporting

First-Principles Study on the Structural, Electronic, Magnetic and Thermodynamic Properties of Full Heusler Alloys Co2VZ (Z = Al, Ga)

NASA Astrophysics Data System (ADS)

Bentouaf, Ali; Hassan, Fouad H.; Reshak, Ali H.; Aïssa, Brahim

2017-01-01

We report on the investigation of the structural and physical properties of the Co2VZ (Z = Al, Ga) Heusler alloys, with L21 structure, through first-principles calculations involving the full potential linearized augmented plane-wave method within density functional theory. These physical properties mainly revolve around the electronic, magnetic and thermodynamic properties. By using the Perdew-Burke-Ernzerhof generalized gradient approximation, the calculated lattice constants and spin magnetic moments were found to be in good agreement with the experimental data. Furthermore, the thermal effects using the quasi-harmonic Debye model have been investigated in depth while taking into account the lattice vibrations, the temperature and the pressure effects on the structural parameters. The heat capacities, the thermal expansion coefficient and the Debye temperatures have also been determined from the non-equilibrium Gibbs functions. An application of the atom in molecule theory is presented and discussed in order to analyze the bonding nature of the Heusler alloys. The focus is on the mixing of the metallic and covalent behavior of Co2VZ (Z = Al, Ga) Heusler alloys.

Future perspectives of personalized medicine in traditional Chinese medicine: a systems biology approach.

PubMed

Zhang, Aihua; Sun, Hui; Wang, Ping; Han, Ying; Wang, Xijun

2012-01-01

Deconstruction of molecular pathways and advances in enabling technology platforms have opened new horizons for disease management, exploring therapeutic solutions to each individual patient beyond the one-size fits all practice. Application of personalized medicine paradigms aims to achieve the right diagnosis and right treatment for the right patient at the right time at the right cost. With the potential to transform medical practice across global communities, personalized medicine is emerging as the flagship of modern medicine. In recent years, the health care paradigm has shifted from a focus on diseases to a major hot of personalized traditional Chinese medicine (TCM) with holistic approach. TCM focuses on health maintenance, emphasizes on enhancing the body's resistance to diseases and especially showes great advantages in early intervention, personalized and combination therapies, etc. Systems biology, a new science of the 21st century, becomes practically available and resembles TCM in many aspects such as study method and design, and is current key component technologies that serves as the major driving force for translation of the personalized medicine revolution of TCM principles into practice, will advance personalized therapy principles into healthcare management tools for individuals and populations. Such system approach concepts are transforming principles of TCM to modern therapeutic approaches, enable a predictive and preventive medicine and will lead to personalized medicine. To realise the full potential of personalized TCM, we describe the current status of principles and practice of TCM integrated with systems biology platform. Some characteristic examples are presented to highlight the application of this platform to personalized TCM research and development as well as some of the necessary milestones for moving TCM into mainstream health care. Copyright © 2011 Elsevier Ltd. All rights reserved.

Non-Exposure, Device-Assisted Endoscopic Full-thickness Resection.

PubMed

Bauder, Markus; Schmidt, Arthur; Caca, Karel

2016-04-01

Recent developments have expanded the frontier of interventional endoscopy toward more extended resections following surgical principles. This article presents two new device-assisted techniques for endoscopic full-thickness resection in the upper and lower gastrointestinal tract. Both methods are nonexposure techniques avoiding exposure of gastrointestinal contents to the peritoneal cavity by a "close first-cut later" principle. The full-thickness resection device is a novel over-the-scope device designed for clip-assisted full-thickness resection of colorectal lesions. Endoscopic full-thickness resection of gastric subepithelial tumors can be performed after placing transmural sutures underneath the tumor with a suturing device originally designed for endoscopic antireflux therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Universal design in diabetes care: an idea whose time has come.

PubMed

Williams, Ann S

2009-01-01

The purpose of this article is to introduce diabetes educators to the emerging concept of universal design (UD): the design of products, environments, and services to be used by persons with a wide range of abilities, without needing adaptation or specialized design. Drawing from the use of the term universal design in a variety of types of writing, this article covers the definition of UD, the contrast of average-person design with UD, principles of UD, and implications for diabetes self-management education (DSME). Implications for DSME are (1) diabetes consumer medical devices (such as blood glucose meters and insulin pumps) can be designed using UD principles, with a goal of successful use by the largest number of persons possible, and (2) diabetes educators can use UD principles in the design of diabetes education programs to reach the largest number of learners possible without the need for special accommodations. Adoption of UD principles by designers of diabetes medical devices could benefit persons with disabilities, increase the potential market for the manufacturer, and have unexpected benefits for people of average abilities. Adoption of UD principles for DSME programs would not require a paradigm change because diabetes educators already do many activities that could contribute to UD of an education program. By replacing average-person design of DSME programs with UD, diabetes educators can promote full participation in DSME for individuals with the wide range of abilities normally present in target populations without the need for added adaptations or specialized design.

Technology integration performance assessment using lean principles in health care.

PubMed

Rico, Florentino; Yalcin, Ali; Eikman, Edward A

2015-01-01

This study assesses the impact of an automated infusion system (AIS) integration at a positron emission tomography (PET) center based on "lean thinking" principles. The authors propose a systematic measurement system that evaluates improvement in terms of the "8 wastes." This adaptation to the health care context consisted of performance measurement before and after integration of AIS in terms of time, utilization of resources, amount of materials wasted/saved, system variability, distances traveled, and worker strain. The authors' observations indicate that AIS stands to be very effective in a busy PET department, such as the one in Moffitt Cancer Center, owing to its accuracy, pace, and reliability, especially after the necessary adjustments are made to reduce or eliminate the source of errors. This integration must be accompanied by a process reengineering exercise to realize the full potential of AIS in reducing waste and improving patient care and worker satisfaction. © The Author(s) 2014.

Electronic and crystal structure of NiTi martensite

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

Sanati, M.; Albers, R.C.; Pinski, F.J.

1998-11-01

All of the first-principles electronic-structure calculations for the martensitic structure of NiTi have used the experimental atomic parameters reported by Michal and Sinclair [Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem. {bold B37}, 1803 (1981)]. We have used first-principles, full-potential, linear muffin-tin orbital calculations to examine the total energy of all the experimental martensitic structures reported in the literature. We find that another crystal structure, that of Kudoh {ital et al.} [Acta Metall. Mater. {bold 33}, 2049 (1985)], has the lowest total energy at zero temperature. Ground-state and formation energies were calculated for all of the experimental structures. Total andmore » local densities of states were calculated and compared with each other for the structures of both Kudoh {ital et al.} and Michal and Sinclair thinsp {copyright} {ital 1998} {ital The American Physical Society}« less

Applying Superresolution Localization-Based Microscopy to Neurons

PubMed Central

ZHONG, HAINING

2016-01-01

Proper brain function requires the precise localization of proteins and signaling molecules on a nanometer scale. The examination of molecular organization at this scale has been difficult in part because it is beyond the reach of conventional, diffraction-limited light microscopy. The recently developed method of superresolution, localization-based fluorescent microscopy (LBM), such as photoactivated localization microscopy (PALM) and stochastic optical reconstruction microscopy (STORM), has demonstrated a resolving power at a 10 nm scale and is poised to become a vital tool in modern neuroscience research. Indeed, LBM has revealed previously unknown cellular architectures and organizational principles in neurons. Here, we discuss the principles of LBM, its current applications in neuroscience, and the challenges that must be met before its full potential is achieved. We also present the unpublished results of our own experiments to establish a sample preparation procedure for applying LBM to study brain tissue. PMID:25648102

Infinite order quantum-gravitational correlations

NASA Astrophysics Data System (ADS)

Knorr, Benjamin

2018-06-01

A new approximation scheme for nonperturbative renormalisation group equations for quantum gravity is introduced. Correlation functions of arbitrarily high order can be studied by resolving the full dependence of the renormalisation group equations on the fluctuation field (graviton). This is reminiscent of a local potential approximation in O(N)-symmetric field theories. As a first proof of principle, we derive the flow equation for the ‘graviton potential’ induced by a conformal fluctuation and corrections induced by a gravitational wave fluctuation. Indications are found that quantum gravity might be in a non-metric phase in the deep ultraviolet. The present setup significantly improves the quality of previous fluctuation vertex studies by including infinitely many couplings, thereby testing the reliability of schemes to identify different couplings to close the equations, and represents an important step towards the resolution of the Nielsen identity. The setup further allows one, in principle, to address the question of putative gravitational condensates.

Are electrostatic potentials between regions of different chemical composition measurable? The Gibbs-Guggenheim Principle reconsidered, extended and its consequences revisited.

PubMed

Pethica, Brian A

2007-12-21

As indicated by Gibbs and made explicit by Guggenheim, the electrical potential difference between two regions of different chemical composition cannot be measured. The Gibbs-Guggenheim Principle restricts the use of classical electrostatics in electrochemical theories as thermodynamically unsound with some few approximate exceptions, notably for dilute electrolyte solutions and concomitant low potentials where the linear limit for the exponential of the relevant Boltzmann distribution applies. The Principle invalidates the widespread use of forms of the Poisson-Boltzmann equation which do not include the non-electrostatic components of the chemical potentials of the ions. From a thermodynamic analysis of the parallel plate electrical condenser, employing only measurable electrical quantities and taking into account the chemical potentials of the components of the dielectric and their adsorption at the surfaces of the condenser plates, an experimental procedure to provide exceptions to the Principle has been proposed. This procedure is now reconsidered and rejected. No other related experimental procedures circumvent the Principle. Widely-used theoretical descriptions of electrolyte solutions, charged surfaces and colloid dispersions which neglect the Principle are briefly discussed. MD methods avoid the limitations of the Poisson-Bolzmann equation. Theoretical models which include the non-electrostatic components of the inter-ion and ion-surface interactions in solutions and colloid systems assume the additivity of dispersion and electrostatic forces. An experimental procedure to test this assumption is identified from the thermodynamics of condensers at microscopic plate separations. The available experimental data from Kelvin probe studies are preliminary, but tend against additivity. A corollary to the Gibbs-Guggenheim Principle is enunciated, and the Principle is restated that for any charged species, neither the difference in electrostatic potential nor the sum of the differences in the non-electrostatic components of the thermodynamic potential difference between regions of different chemical compositions can be measured.

Ab-initio investigations for opto-electronic response of (Cd, Zn)Ga2Te4: Promising solar PV materials

NASA Astrophysics Data System (ADS)

Sahariya, Jagrati; Soni, Amit; Kumar, Pancham

2018-04-01

In this paper, the first principle calculations are performed to analyze the structural, electronic and optical behavior of promising solar materials (Cd,Zn)Ga2Te4. To perform these calculations we have used one of the most accurate Full Potential Linearized Augmented Plane Wave (FP-LAPW) method. The ground state properties of these compounds are confirmed over here after proper examination of energy and charge convergence using Perdew-Burke-Ernzerhof (PBE-sol) exchange correlation potential. The investigations performed such as energy band structure, Density of States (DOS), optical parameters like complex dielectric function and absorption co-efficient are discussed over here to understand the overall response of the chosen system.

Understanding the Origin of Species with Genome-Scale Data: the Role of Gene Flow

PubMed Central

Sousa, Vitor; Hey, Jody

2017-01-01

As it becomes easier to sequence multiple genomes from closely related species, evolutionary biologists working on speciation are struggling to get the most out of very large population-genomic data sets. Such data hold the potential to resolve evolutionary biology’s long-standing questions about the role of gene exchange in species formation. In principle the new population genomic data can be used to disentangle the conflicting roles of natural selection and gene flow during the divergence process. However there are great challenges in taking full advantage of such data, especially with regard to including recombination in genetic models of the divergence process. Current data, models, methods and the potential pitfalls in using them will be considered here. PMID:23657479

Coupled fluid-structure interaction. Part 1: Theory. Part 2: Application

NASA Technical Reports Server (NTRS)

Felippa, Carlos A.; Ohayon, Roger

1991-01-01

A general three dimensional variational principle is obtained for the motion of an acoustic field enclosed in a rigid or flexible container by the method of canonical decomposition applied to a modified form of the wave equation in the displacement potential. The general principle is specialized to a mixed two-field principle that contains the fluid displacement potential and pressure as independent fields. Semidiscrete finite element equations of motion based on this principle are derived and sample cases are given.

First principles study of structural, electronic and optical properties of perovskites CaZrO3 and CaHfO3 in cubic phase

NASA Astrophysics Data System (ADS)

Hoat, D. M.; Silva, J. F. Rivas; Blas, A. Méndez

2018-07-01

In this work, we present the first principles calculations for structural, electronic and optical properties of perovskites CaZrO3 and CaHfO3 using the full-potential linearized augmented plane wave method (FP-LAPW) within the framework of density functional theory (DFT) as implemented in WIEN2k package. The exchange-correlation potential is treated with local density approximation (LDA) and generalized gradient approximation (GGA-PBE and PBESol). Additionally, the Tran Blaha modified Becke-Johnson exchange potential (mBJ) also is employed for electronic and optical calculations due to that it gives very accurate band gap of solids. Our obtained structural parameters are in good agreement with experimental datas and other theoretical results. The energy band gap obtained with mBJ is 4.56 eV for CaZrO3 and 5.27 eV for CaHfO3. The hybridization of states of O atom with those of Zr and Hf atoms in CaZrO3 and CaHfO3, respectively, is observed. The spin-orbit coupling effect on electronic properties of considered compounds also is investigated. Finally, the linear optical properties of CaZrO3 and CaHfO3 are derived from their complex dielectric function calculated with mBJ potential for wide energy range up to 45 eV, and all of them analyzed in details.

Guiding Principles for Data Requirements

EPA Pesticide Factsheets

The principles in the document are intended to help guide the identification of data needs, promote and optimize full use of existing knowledge, provide consistency in the data request process across all scientific disciplines for pesticide review.

Data principles for the U.S. Global Change Research Program

NASA Technical Reports Server (NTRS)

Ludwig, George H.; Shaffer, Lisa R.

1991-01-01

The U.S. Interagency Working Group on Data Management for Global Change has developed a set of data management and access principles. The overall purpose of these statements of principle is to stimulate responsible stewardship for data and related information and to facilitate full and open access to them. These statements have been accepted by the U.S. Agencies responsible for the Global Change Research Program. The statements of principle are presented and discussed.

From Frozen Ties to Strategic Engagement: U.S.-Iranian Relationship in 2030

DTIC Science & Technology

2015-05-01

rest xiv on the principle and practice of selective engagement, but with an understanding and direction to a more full-fledged strategic relationship...likely rest on the principle and practice of selective engagement, but with an understanding and direction to a more full-fledged strategic...occasionally rebuffed U.S. engagement at- tempts, citing Washington’s lack of respect. The lack of understanding in Washington of diverg- ing views of

First-principles study of electronic structure and Fermi surface in semimetallic YAs

DOE PAGES

Swatek, Przemys?aw Wojciech

2018-03-23

In the course of searching for new systems, which exhibit nonsaturating and extremely large positive magnetoresistance, electronic structure, Fermi surface, and de Haas-van Alphen characteristics of the semimetallic YAs compound were studied using the all-electron full-potential linearized augmented-plane wave (FP–LAPW) approach in the framework of the generalized gradient approximation (GGA). In the scalar-relativistic calculation, the cubic symmetry splits fivefold degenerate Y- d orbital into low-energy threefold-degenerate and twofold degenerate doublet states at point around the Fermi energy. Furthermore one of them, together with the threefold degenerate character of As-p orbital, render the YAs semimetal with a topologically trivial band ordermore » and fairly low density of states at the Fermi level. Including spin–orbit (SO) coupling into the calculation leads to pronounced splitting of the state and shifting the bands in the energy scale. Consequently, the determined four different 3-dimensional Fermi surface sheets of YAs consists of three concentric hole-like bands at and one ellipsoidal electron-like sheet centred at the X points. In full accordance with the previous first-principles calculations for isostructural YSb and YBi, the calculated Fermi surface of YAs originates from fairly compensated multi-band electronic structures.« less

First-principles study of electronic structure and Fermi surface in semimetallic YAs

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

Swatek, Przemys?aw Wojciech

In the course of searching for new systems, which exhibit nonsaturating and extremely large positive magnetoresistance, electronic structure, Fermi surface, and de Haas-van Alphen characteristics of the semimetallic YAs compound were studied using the all-electron full-potential linearized augmented-plane wave (FP–LAPW) approach in the framework of the generalized gradient approximation (GGA). In the scalar-relativistic calculation, the cubic symmetry splits fivefold degenerate Y- d orbital into low-energy threefold-degenerate and twofold degenerate doublet states at point around the Fermi energy. Furthermore one of them, together with the threefold degenerate character of As-p orbital, render the YAs semimetal with a topologically trivial band ordermore » and fairly low density of states at the Fermi level. Including spin–orbit (SO) coupling into the calculation leads to pronounced splitting of the state and shifting the bands in the energy scale. Consequently, the determined four different 3-dimensional Fermi surface sheets of YAs consists of three concentric hole-like bands at and one ellipsoidal electron-like sheet centred at the X points. In full accordance with the previous first-principles calculations for isostructural YSb and YBi, the calculated Fermi surface of YAs originates from fairly compensated multi-band electronic structures.« less

Constructing first-principles phase diagrams of amorphous LixSi using machine-learning-assisted sampling with an evolutionary algorithm

NASA Astrophysics Data System (ADS)

Artrith, Nongnuch; Urban, Alexander; Ceder, Gerbrand

2018-06-01

The atomistic modeling of amorphous materials requires structure sizes and sampling statistics that are challenging to achieve with first-principles methods. Here, we propose a methodology to speed up the sampling of amorphous and disordered materials using a combination of a genetic algorithm and a specialized machine-learning potential based on artificial neural networks (ANNs). We show for the example of the amorphous LiSi alloy that around 1000 first-principles calculations are sufficient for the ANN-potential assisted sampling of low-energy atomic configurations in the entire amorphous LixSi phase space. The obtained phase diagram is validated by comparison with the results from an extensive sampling of LixSi configurations using molecular dynamics simulations and a general ANN potential trained to ˜45 000 first-principles calculations. This demonstrates the utility of the approach for the first-principles modeling of amorphous materials.

A Canadian framework for applying the precautionary principle to public health issues.

PubMed

Weir, Erica; Schabas, Richard; Wilson, Kumanan; Mackie, Chris

2010-01-01

The precautionary principle has influenced environmental and public health policy. It essentially states that complete evidence of a potential risk is not required before action is taken to mitigate the effects of the potential risk. The application of precaution to public health issues is not straightforward and could paradoxically cause harm to the public's health when applied inappropriately. To avoid this, we propose a framework for applying the precautionary principle to potential public health risks. The framework consists of ten guiding questions to help establish whether a proposed application of the precautionary principle on a public health matter is based on adequacy of the evidence of causation, severity of harm and acceptability of the precautionary measures.

Plan of Action for Real-World Translation of LGBTQ Health and Aging Research.

PubMed

Fredriksen-Goldsen, Karen I; Kim, Hyun-Jun; McKenzie, Glenise L; Krinsky, Lisa; Emlet, Charles A

2017-12-01

Despite accumulating evidence of health disparities, there exists limited translational research to enhance optimal health and aging of lesbian, gay, bisexual, transgender, and queer-identified * (LGBTQ) older adults. Based on the Health Equity Promotion Model that addresses the distinct needs and strengths of LGBTQ older adults, we underscore the important role of collaborations among researchers, practitioners, and communities to build community capacity. Given the rapidly shifting context, we advance principles to guide future work that will enhance translational research and the development of evidence-based practice so that LGBTQ older adults can reach their full health potential.

First-Principles Prediction of Electronic, Magnetic, and Optical Properties of Co2MnAs Full-Heusler Half-Metallic Compound

NASA Astrophysics Data System (ADS)

Bakhshayeshi, A.; Sarmazdeh, M. Majidiyan; Mendi, R. Taghavi; Boochani, A.

2017-04-01

Electronic, magnetic, and optical properties of Co2MnAs full-Heusler compound have been calculated using a first-principles approach with the full-potential linearized augmented plane-wave (FP-LAPW) method and generalized gradient approximation plus U (GGA + U). The results are compared with various properties of Co2Mn Z ( Z = Si, Ge, Al, Ga, Sn) full-Heusler compounds. The results of our calculations show that Co2MnAs is a half-metallic ferromagnetic compound with 100% spin polarization at the Fermi level. The total magnetic moment and half-metallic gap of Co2MnAs compound are found to be 6.00 μ B and 0.43 eV, respectively. It is also predicted that the spin-wave stiffness constant and Curie temperature of Co2MnAs compound are about 3.99 meV nm2 and 1109 K, respectively. The optical results show that the dominant behavior, at energy below 2 eV, is due to interactions of free electrons in the system. Interband optical transitions have been calculated based on the imaginary part of the dielectric function and analysis of critical points in the second energy derivative of the dielectric function. The results show that there is more than one plasmon energy for Co2MnAs compound, with the highest occurring at 25 eV. Also, the refractive index variations and optical reflectivity for radiation at normal incidence are calculated for Co2MnAs. Because of its high magnetic moment, high Curie temperature, and 100% spin polarization at the Fermi level as well as its optical properties, Co2MnAs is a good candidate for use in spintronic components and magnetooptical devices.

Damn the Permanganate Volcanoes: Full Principles Ahead.

ERIC Educational Resources Information Center

Pilar, Frank L.

1981-01-01

Discusses whether chemistry should be taught using a purely descriptive approach or using the current "principles" approach. Considers what sort of background should be provided given the uses students are most apt to make of their general chemistry training. (SK)

Density-functional formulation of the generalized pseudopotential theory. III. Transition-metal interatomic potentials

NASA Astrophysics Data System (ADS)

Moriarty, John A.

1988-08-01

The first-principles, density-functional version of the generalized pseudopotential theory (GPT) developed in papers I and II of this series [Phys. Rev. B 16, 2537 (1977); 26, 1754 (1982)] for empty- and filled-d-band metals is here extended to pure transition metals with partially filled d bands. The present focus is on a rigorous, real-space expansion of the bulk total energy in terms of widely transferable, structure-independent interatomic potentials, including both central-force pair interactions and angular-force triplet and quadruplet interactions. To accomplish this expansion, a specialized set of starting equations is derived from the basic local-density formalism for a pure metal, including refined expansions for the exchange-correlation terms and a simplified yet accurate representation of the cohesive energy. The parent pseudo-Green's-function formalism of the GPT is then used to develop these equations in a plane-wave, localized-d-state basis. In this basis, the cohesive energy divides quite naturally into a large volume component and a smaller structural component. The volume component,which includes all one-ion intra-atomic energy contributions, already gives a good description of the cohesion in lowest order. The structural component is expanded in terms of weak interatomic matrix elements and gives rise to a multi-ion series which establishes the interatomic potentials. Special attention is focused on the dominant d-electron contributions to this series and complete formal results for the two-ion, three-ion, and four-ion d-state potentials (vd2, vd3, and vd4) are derived. In addition, a simplified model is used to demonstrate that while vd3 can be of comparable importance to vd2, vd4 is inherently small and the series is rapidly convergent beyond three-ion interactions. Analytic model forms are also derived for vd2 and vd3 in the case of canonical d bands. In this limit, vd2 is purely attractive and varies with interatomic distance as r-10, while vd3 is weak and attractive for almost empty or filled d bands and maximum in strength and repulsive for half-filled d bands. Full first-principles expressions are then developed for the total two-ion and three-ion potentials and implemented for all 20 3d and 4d transition metals. The first-principles potentials qualitatively display all of the trends predicted by the model results, but they also reflect additional effects, including long-range hybridization tails which must be suitably screened in real-space calculations. Finally, illustrative application of the first-principles potentials is made to the calculation of the [100] phonon spectrum for V and Cr, where the importance of three-ion angular forces is explicitly demonstrated.

Why not private health insurance? 1. Insurance made easy

PubMed Central

Deber, R; Gildiner, A; Baranek, P

1999-01-01

How realistic are proposals to expand the financing of Canadian health care through private insurance, either in a parallel stream or an expanded supplementary tier? Any successful business requires that revenues exceed expenditures. Under a voluntary health insurance plan those at highest risk would be the most likely to seek coverage; insurers working within a competitive market would have to limit their financial risk through such mechanisms as "risk selection" to avoid clients likely to incur high costs and/or imposing caps on the costs covered. It is unlikely that parallel private plans will have a market if a comprehensive public insurance system continues to exist and function well. Although supplementary plans are more congruous with insurance principles, they would raise costs for purchasers and would probably not provide full open-ended coverage to all potential clients. Insurance principles suggest that voluntary insurance plans that shift costs to the private sector would damage the publicly funded system and would be unable to cover costs for all services required. PMID:10497613

First-principles study of structural, electronic, linear and nonlinear optical properties of Ga{2}PSb ternary chalcopyrite

NASA Astrophysics Data System (ADS)

Ouahrani, T.; Reshak, A. H.; de La Roza, A. Otero; Mebrouki, M.; Luaña, V.; Khenata, R.; Amrani, B.

2009-12-01

We report results from first-principles density functional calculations using the full-potential linear augmented plane wave (FP-LAPW) method. The generalized gradient approximation (GGA) and the Engel-Vosko-generalized gradient approximation (EV-GGA) were used for the exchange-correlation energy of the structural, electronic, linear and nonlinear optical properties of the chalcopyrite Ga2PSb compound. The valence band maximum (VBM) is located at the Γv point, and the conduction band minimum (CBM) is located at the Γc point, resulting in a direct band gap of about 0.365 eV for GGA and 0.83 eV for EV-GGA. In comparison with the experimental one (1.2 eV) we found that EV-GGA calculation gives energy gap in reasonable agreement with the experiment. The spin orbit coupling has marginal influence on the optical properties. The ground state quantities such as lattice parameters (a, c and u), bulk modules B and its pressure derivative B^primeare evaluated.

Health data use, stewardship, and governance: ongoing gaps and challenges: a report from AMIA's 2012 Health Policy Meeting

PubMed Central

Hripcsak, George; Bloomrosen, Meryl; FlatelyBrennan, Patti; Chute, Christopher G; Cimino, Jim; Detmer, Don E; Edmunds, Margo; Embi, Peter J; Goldstein, Melissa M; Hammond, William Ed; Keenan, Gail M; Labkoff, Steve; Murphy, Shawn; Safran, Charlie; Speedie, Stuart; Strasberg, Howard; Temple, Freda; Wilcox, Adam B

2014-01-01

Large amounts of personal health data are being collected and made available through existing and emerging technological media and tools. While use of these data has significant potential to facilitate research, improve quality of care for individuals and populations, and reduce healthcare costs, many policy-related issues must be addressed before their full value can be realized. These include the need for widely agreed-on data stewardship principles and effective approaches to reduce or eliminate data silos and protect patient privacy. AMIA's 2012 Health Policy Meeting brought together healthcare academics, policy makers, and system stakeholders (including representatives of patient groups) to consider these topics and formulate recommendations. A review of a set of Proposed Principles of Health Data Use led to a set of findings and recommendations, including the assertions that the use of health data should be viewed as a public good and that achieving the broad benefits of this use will require understanding and support from patients. PMID:24169275

Health data use, stewardship, and governance: ongoing gaps and challenges: a report from AMIA's 2012 Health Policy Meeting.

PubMed

Hripcsak, George; Bloomrosen, Meryl; FlatelyBrennan, Patti; Chute, Christopher G; Cimino, Jim; Detmer, Don E; Edmunds, Margo; Embi, Peter J; Goldstein, Melissa M; Hammond, William Ed; Keenan, Gail M; Labkoff, Steve; Murphy, Shawn; Safran, Charlie; Speedie, Stuart; Strasberg, Howard; Temple, Freda; Wilcox, Adam B

2014-01-01

Large amounts of personal health data are being collected and made available through existing and emerging technological media and tools. While use of these data has significant potential to facilitate research, improve quality of care for individuals and populations, and reduce healthcare costs, many policy-related issues must be addressed before their full value can be realized. These include the need for widely agreed-on data stewardship principles and effective approaches to reduce or eliminate data silos and protect patient privacy. AMIA's 2012 Health Policy Meeting brought together healthcare academics, policy makers, and system stakeholders (including representatives of patient groups) to consider these topics and formulate recommendations. A review of a set of Proposed Principles of Health Data Use led to a set of findings and recommendations, including the assertions that the use of health data should be viewed as a public good and that achieving the broad benefits of this use will require understanding and support from patients.

An Exploratory Review of Design Principles in Constructivist Gaming Learning Environments

ERIC Educational Resources Information Center

Rosario, Roberto A. Munoz; Widmeyer, George R.

2009-01-01

Creating a design theory for Constructivist Gaming Learning Environment necessitates, among other things, the establishment of design principles. These principles have the potential to help designers produce games, where users achieve higher levels of learning. This paper focuses on twelve design principles: Probing, Distributed, Multiple Routes,…

Role of structural relaxations and chemical substitutions on piezoelectric fields and potential lineup in GaN/Al junctions

NASA Astrophysics Data System (ADS)

Picozzi, S.; Profeta, G.; Continenza, A.; Massidda, S.; Freeman, A. J.

2002-04-01

First-principles full-potential linearized augmented plane wave calculations are performed to clarify the role of the interface geometry on piezoelectric fields and potential lineups in [0001] wurtzite and [111]-zincblende GaN/Al junctions. The electric field (polarity and magnitude) is found to be strongly affected by atomic relaxations in the interface region. A procedure is used to evaluate the Schottky-barrier height in the presence of electric fields, showing that their effect is relatively small (a few tenths of an eV). These calculations assess the rectifying behavior of the GaN/Al contact, in agreement with experimental values for the barrier. We disentangle chemical and structural effects on the relevant properties (such as the potential discontinuity and the electric field) by studying unrelaxed ideal nitride/metal systems. Using simple electronegativity arguments, we outline the leading mechanisms that define the values of the electric field and Schottky barrier in these ideal systems. Finally, the transitivity rule is proved to be well satisfied.

Nootropic potential of Ashwagandha leaves: Beyond traditional root extracts.

PubMed

Wadhwa, Renu; Konar, Arpita; Kaul, Sunil C

2016-05-01

Rapidly increasing aging population and environmental stressors are the two main global concerns of the modern society. These have brought in light rapidly increasing incidence of a variety of pathological conditions including brain tumors, neurodegenerative & neuropsychiatric disorders, and new challenges for their treatment. The overlapping symptoms, complex etiology and lack of full understanding of the brain structure and function to-date further complicate these tasks. On the other hand, several herbal reagents with a long history of their use have been asserted to possess neurodifferentiation, neuroregenerative and neuroprotective potentials, and hence been recommended as supplement to enhance and maintain brain health and function. Although they have been claimed to function by holistic approach resulting in maintaining body homeostasis and brain health, there are not enough laboratory studies in support to these and mechanism(s) of such beneficial activities remain largely undefined. One such herb is Ashwagandha, also called "Queen of Ayurveda" for its popular use in Indian traditional home medicine because of its extensive benefits including anticancer, anti-stress and remedial potential for aging and neurodegenerative pathologies. However, active principles and underlying mechanism(s) of action remain largely unknown. Here we provide a review on the effects of Ashwagandha extracts and active principles, and underlying molecular mechanism(s) for brain pathologies. We highlight our findings on the nootropic potential of Ashwagandha leaves. The effects of Ashwagandha leaf extracts are multidimensional ranging from differentiation of neuroblastoma and glioma cells, reversal of Alzheimer and Parkinson's pathologies, protection against environmental neurotoxins and enhancement of memory. Copyright © 2015 Elsevier Ltd. All rights reserved.

Stationary variational estimates for the effective response and field fluctuations in nonlinear composites

NASA Astrophysics Data System (ADS)

Ponte Castañeda, Pedro

2016-11-01

This paper presents a variational method for estimating the effective constitutive response of composite materials with nonlinear constitutive behavior. The method is based on a stationary variational principle for the macroscopic potential in terms of the corresponding potential of a linear comparison composite (LCC) whose properties are the trial fields in the variational principle. When used in combination with estimates for the LCC that are exact to second order in the heterogeneity contrast, the resulting estimates for the nonlinear composite are also guaranteed to be exact to second-order in the contrast. In addition, the new method allows full optimization with respect to the properties of the LCC, leading to estimates that are fully stationary and exhibit no duality gaps. As a result, the effective response and field statistics of the nonlinear composite can be estimated directly from the appropriately optimized linear comparison composite. By way of illustration, the method is applied to a porous, isotropic, power-law material, and the results are found to compare favorably with earlier bounds and estimates. However, the basic ideas of the method are expected to work for broad classes of composites materials, whose effective response can be given appropriate variational representations, including more general elasto-plastic and soft hyperelastic composites and polycrystals.

Nitrogen-doped fullerene as a potential catalyst for hydrogen fuel cells.

PubMed

Gao, Feng; Zhao, Guang-Lin; Yang, Shizhong; Spivey, James J

2013-03-06

We examine the possibility of nitrogen-doped C60 fullerene (N-C60) as a cathode catalyst for hydrogen fuel cells. We use first-principles spin-polarized density functional theory calculations to simulate the electrocatalytic reactions on N-C60. The first-principles results show that an O2 molecule can be adsorbed and partially reduced on the N-C complex sites (Pauling sites) of N-C60 without any activation barrier. Through a direct pathway, the partially reduced O2 can further react with H(+) and additional electrons and complete the water formation reaction (WFR) with no activation energy barrier. In the indirect pathway, reduced O2 reacts with H(+) and additional electrons to form H2O molecules through a transition state (TS) with a small activation barrier (0.22-0.37 eV). From an intermediate state to a TS, H(+) can obtain a kinetic energy of ∼0.95-3.68 eV, due to the Coulomb electric interaction, and easily overcome the activation energy barrier during the WFR. The full catalytic reaction cycles can be completed energetically, and N-C60 fullerene recovers to its original structure for the next catalytic reaction cycle. N-C60 fullerene is a potential cathode catalyst for hydrogen fuel cells.

The rise and fall of democratic universalism: health care reform in Italy, 1978-1994.

PubMed

Ferrera, M

1995-01-01

In 1978, a sweeping reform created the first national health service of continental Europe: Italy's Servizio Sanitario Nazionale. This new scheme was based on the principle of "full democratic universalism": The state would provide free and equal benefits to every citizen and the organization of public health would subject to popular control, essentially through political parties. However, the severe problems encountered in implementing the reform design and rapidly increasing health expenditures soon eroded any consensus on this principle. Thus the 1980s and early 1990s witnessed a gradual shift to "conditional and well managed universalism." These latter principles stress the need to differentiate access to care according to some criterion to regulate demand and the need for efficient use of scarce resources through adequate valorization of managerial skills and the use of "market-type" incentives. An elaborated system of user copayments was introduced gradually, and in 1992 a "reform of the reform" profoundly changed the organizational framework of the Servizio Sanitario Nazionale. The new government elected in the spring of 1994 announced ambitious plans to partially dismantle public universal insurance. Although these plans may prove difficult, the potential to form an anti-universalistic coalition seems strong in the contemporary Italian health care arena.

Mixed variational formulations of finite element analysis of elastoacoustic/slosh fluid-structure interaction

NASA Technical Reports Server (NTRS)

Felippa, Carlos A.; Ohayon, Roger

1991-01-01

A general three-field variational principle is obtained for the motion of an acoustic fluid enclosed in a rigid or flexible container by the method of canonical decomposition applied to a modified form of the wave equation in the displacement potential. The general principle is specialized to a mixed two-field principle that contains the fluid displacement potential and pressure as independent fields. This principle contains a free parameter alpha. Semidiscrete finite-element equations of motion based on this principle are displayed and applied to the transient response and free-vibrations of the coupled fluid-structure problem. It is shown that a particular setting of alpha yields a rich set of formulations that can be customized to fit physical and computational requirements. The variational principle is then extended to handle slosh motions in a uniform gravity field, and used to derive semidiscrete equations of motion that account for such effects.

Quantum corrections to newtonian potential and generalized uncertainty principle

NASA Astrophysics Data System (ADS)

Scardigli, Fabio; Lambiase, Gaetano; Vagenas, Elias

2017-08-01

We use the leading quantum corrections to the newtonian potential to compute the deformation parameter of the generalized uncertainty principle. By assuming just only General Relativity as theory of Gravitation, and the thermal nature of the GUP corrections to the Hawking spectrum, our calculation gives, to first order, a specific numerical result. We briefly discuss the physical meaning of this value, and compare it with the previously obtained bounds on the generalized uncertainty principle deformation parameter.

39 CFR 602.1 - General principles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Service UNITED STATES POSTAL SERVICE PROCUREMENT SYSTEM FOR THE U.S. POSTAL SERVICE: INTELLECTUAL PROPERTY RIGHTS OTHER THAN PATENTS INTELLECTUAL PROPERTY RIGHTS OTHER THAN PATENTS § 602.1 General principles. It is the policy of the Postal Service to secure full ownership rights for its intellectual properties...

21 CFR 809.10 - Labeling for in vitro diagnostic products.

Code of Federal Regulations, 2010 CFR

2010-04-01

... principles of the procedure. Explain concisely, with chemical reactions and techniques involved, if...) Instruments: (i) Use or function. (ii) Installation procedures and special requirements. (iii) Principles of... product testing prior to full commercial marketing (for example, for use on specimens derived from humans...

Subaperture correlation based digital adaptive optics for full field optical coherence tomography.

PubMed

Kumar, Abhishek; Drexler, Wolfgang; Leitgeb, Rainer A

2013-05-06

This paper proposes a sub-aperture correlation based numerical phase correction method for interferometric full field imaging systems provided the complex object field information can be extracted. This method corrects for the wavefront aberration at the pupil/ Fourier transform plane without the need of any adaptive optics, spatial light modulators (SLM) and additional cameras. We show that this method does not require the knowledge of any system parameters. In the simulation study, we consider a full field swept source OCT (FF SSOCT) system to show the working principle of the algorithm. Experimental results are presented for a technical and biological sample to demonstrate the proof of the principle.

An implementation of the maximum-caliber principle by replica-averaged time-resolved restrained simulations

NASA Astrophysics Data System (ADS)

Capelli, Riccardo; Tiana, Guido; Camilloni, Carlo

2018-05-01

Inferential methods can be used to integrate experimental informations and molecular simulations. The maximum entropy principle provides a framework for using equilibrium experimental data, and it has been shown that replica-averaged simulations, restrained using a static potential, are a practical and powerful implementation of such a principle. Here we show that replica-averaged simulations restrained using a time-dependent potential are equivalent to the principle of maximum caliber, the dynamic version of the principle of maximum entropy, and thus may allow us to integrate time-resolved data in molecular dynamics simulations. We provide an analytical proof of the equivalence as well as a computational validation making use of simple models and synthetic data. Some limitations and possible solutions are also discussed.

An implementation of the maximum-caliber principle by replica-averaged time-resolved restrained simulations.

PubMed

Capelli, Riccardo; Tiana, Guido; Camilloni, Carlo

2018-05-14

Inferential methods can be used to integrate experimental informations and molecular simulations. The maximum entropy principle provides a framework for using equilibrium experimental data, and it has been shown that replica-averaged simulations, restrained using a static potential, are a practical and powerful implementation of such a principle. Here we show that replica-averaged simulations restrained using a time-dependent potential are equivalent to the principle of maximum caliber, the dynamic version of the principle of maximum entropy, and thus may allow us to integrate time-resolved data in molecular dynamics simulations. We provide an analytical proof of the equivalence as well as a computational validation making use of simple models and synthetic data. Some limitations and possible solutions are also discussed.

THE MAXIMIUM POWER PRINCIPLE: AN EMPIRICAL INVESTIGATION

EPA Science Inventory

The maximum power principle is a potential guide to understanding the patterns and processes of ecosystem development and sustainability. The principle predicts the selective persistence of ecosystem designs that capture a previously untapped energy source. This hypothesis was in...

Open Science: a first step towards Science Communication

NASA Astrophysics Data System (ADS)

Grigorov, Ivo; Tuddenham, Peter

2015-04-01

As Earth Science communicators gear up to adopt the new tools and captivating approaches to engage citizen scientists, budding entrepreneurs, policy makers and the public in general, researchers have the responsibility, and opportunity, to fully adopt Open Science principles and capitalize on its full societal impact and engagement. Open Science is about removing all barriers to basic research, whatever its formats, so that it can be freely used, re-used and re-hashed, thus fueling discourse and accelerating generation of innovative ideas. The concept is central to EU's Responsible Research and Innovation philosophy, and removing barriers to basic research measurably contributes to engaging citizen scientists into the research process, it sets the scene for co-creation of solutions to societal challenges, and raises the general science literacy level of the public. Despite this potential, only 50% of today's basic research is freely available. Open Science can be the first passive step of communicating marine research outside academia. Full and unrestricted access to our knowledge including data, software code and scientific publications is not just an ethical obligation, but also gives solid credibility to a more sophisticated communication strategy on engaging society. The presentation will demonstrate how Open Science perfectly compliments a coherent communication strategy for placing Marine Research in societal context, and how it underpin an effective integration of Ocean & Earth Literacy principles in standard educational, as well mobilizing citizen marine scientists, thus making marine science Open Science.

Plan of Action for Real-World Translation of LGBTQ Health and Aging Research

PubMed Central

Kim, Hyun-Jun; McKenzie, Glenise L.; Krinsky, Lisa; Emlet, Charles A.

2017-01-01

Abstract Despite accumulating evidence of health disparities, there exists limited translational research to enhance optimal health and aging of lesbian, gay, bisexual, transgender, and queer-identified* (LGBTQ) older adults. Based on the Health Equity Promotion Model that addresses the distinct needs and strengths of LGBTQ older adults, we underscore the important role of collaborations among researchers, practitioners, and communities to build community capacity. Given the rapidly shifting context, we advance principles to guide future work that will enhance translational research and the development of evidence-based practice so that LGBTQ older adults can reach their full health potential. PMID:29099666

Toward an instructionally oriented theory of example-based learning.

PubMed

Renkl, Alexander

2014-01-01

Learning from examples is a very effective means of initial cognitive skill acquisition. There is an enormous body of research on the specifics of this learning method. This article presents an instructionally oriented theory of example-based learning that integrates theoretical assumptions and findings from three research areas: learning from worked examples, observational learning, and analogical reasoning. This theory has descriptive and prescriptive elements. The descriptive subtheory deals with (a) the relevance and effectiveness of examples, (b) phases of skill acquisition, and (c) learning processes. The prescriptive subtheory proposes instructional principles that make full exploitation of the potential of example-based learning possible. Copyright © 2013 Cognitive Science Society, Inc.

Robust half-metallic ferromagnetism and curvature dependent magnetic coupling in fluorinated boron nitride nanotubes.

PubMed

Guo, Chunsheng; Zhou, Yu; Shi, Xin-Qiang; Gan, Li-Yong; Jiang, Hong; Zhao, Yong

2016-04-28

The fluorinated boron nitride (F-BN) nanostructures are found to be fully spin polarized and half-metallic by means of first-principles calculations based on the Heyd-Scuseria-Ernzerhof hybrid functional. It is found that the full spin polarization and 1 μB local moment in F-BN nanotubes are independent of tube radius and it is also robust in planar ribbons and sheets. The long-ranged ferromagnetic coupling between local moments decreases with decreasing tube radius. This suggests that F-BN systems with small local curvatures could be more easily experimentally observed and have greater potential applications in spin devices.

First principle study of UHTC ternary diboride, Cr2AlB2

NASA Astrophysics Data System (ADS)

Rastogi, Anugya; Rajpoot, Priyanka; Verma, U. P.

2018-04-01

In this paper ab-initio study of the structural, electronic and optical properties of ternary metal boride Cr2AlB2 using full potential linear augmented plane wave (FP-LAPW) method based on the density functional theory (DFT). The study of structural properties shows that Cr2AlB2 is metallic in nature and have orthorhombic crystal structure. The optical properties show that it possess anisotropic behavior, which have wide applications in electricity production through concentration of solar power (CSP) technology. To the best of our knowledge, theoretical study of the optical properties of Cr2AlB2 is reported for the first time.

An efficient method for quantum transport simulations in the time domain

NASA Astrophysics Data System (ADS)

Wang, Y.; Yam, C.-Y.; Frauenheim, Th.; Chen, G. H.; Niehaus, T. A.

2011-11-01

An approximate method based on adiabatic time dependent density functional theory (TDDFT) is presented, that allows for the description of the electron dynamics in nanoscale junctions under arbitrary time dependent external potentials. The density matrix of the device region is propagated according to the Liouville-von Neumann equation. The semi-infinite leads give rise to dissipative terms in the equation of motion which are calculated from first principles in the wide band limit. In contrast to earlier ab initio implementations of this formalism, the Hamiltonian is here approximated in the spirit of the density functional based tight-binding (DFTB) method. Results are presented for two prototypical molecular devices and compared to full TDDFT calculations. The temporal profile of the current traces is qualitatively well captured by the DFTB scheme. Steady state currents show considerable variations, both in comparison of approximate and full TDDFT, but also among TDDFT calculations with different basis sets.

Parallelization of the FLAPW method

NASA Astrophysics Data System (ADS)

Canning, A.; Mannstadt, W.; Freeman, A. J.

2000-08-01

The FLAPW (full-potential linearized-augmented plane-wave) method is one of the most accurate first-principles methods for determining structural, electronic and magnetic properties of crystals and surfaces. Until the present work, the FLAPW method has been limited to systems of less than about a hundred atoms due to the lack of an efficient parallel implementation to exploit the power and memory of parallel computers. In this work, we present an efficient parallelization of the method by division among the processors of the plane-wave components for each state. The code is also optimized for RISC (reduced instruction set computer) architectures, such as those found on most parallel computers, making full use of BLAS (basic linear algebra subprograms) wherever possible. Scaling results are presented for systems of up to 686 silicon atoms and 343 palladium atoms per unit cell, running on up to 512 processors on a CRAY T3E parallel supercomputer.

Insurance principles and the design of prospective payment systems.

PubMed

Ellis, R P; McGuire, T G

1988-09-01

This paper applies insurance principles to the issues of optimal outlier payments and designation of peer groups in Medicare's case-based prospective payment system for hospital care. Arrow's principle that full insurance after a deductible is optimal implies that, to minimize hospital risk, outlier payments should be based on hospital average loss per case rather than, as at present, based on individual case-level losses. The principle of experience rating implies defining more homogenous peer groups for the purpose of figuring average cost. The empirical significance of these results is examined using a sample of 470,568 discharges from 469 hospitals.

39 CFR 602.1 - General principles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 39 Postal Service 1 2014-07-01 2014-07-01 false General principles. 602.1 Section 602.1 Postal Service UNITED STATES POSTAL SERVICE PROCUREMENT SYSTEM FOR THE U.S. POSTAL SERVICE: INTELLECTUAL PROPERTY... is the policy of the Postal Service to secure full ownership rights for its intellectual properties...

39 CFR 602.1 - General principles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 39 Postal Service 1 2012-07-01 2012-07-01 false General principles. 602.1 Section 602.1 Postal Service UNITED STATES POSTAL SERVICE PROCUREMENT SYSTEM FOR THE U.S. POSTAL SERVICE: INTELLECTUAL PROPERTY... is the policy of the Postal Service to secure full ownership rights for its intellectual properties...

39 CFR 602.1 - General principles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 39 Postal Service 1 2013-07-01 2013-07-01 false General principles. 602.1 Section 602.1 Postal Service UNITED STATES POSTAL SERVICE PROCUREMENT SYSTEM FOR THE U.S. POSTAL SERVICE: INTELLECTUAL PROPERTY... is the policy of the Postal Service to secure full ownership rights for its intellectual properties...

Expanding the three Rs to meet new challenges in humane animal experimentation.

PubMed

Schuppli, Catherine A; Fraser, David; McDonald, Michael

2004-11-01

The Three Rs are the main principles used by Animal Ethics Committees in the governance of animal experimentation, but they appear not to cover some ethical issues that arise today. These include: a) claims that certain species should be exempted on principle from harmful research; b) increased emphasis on enhancing quality of life of research animals; c) research involving genetically modified (GM) animals; and d) animals bred as models of disease. In some cases, the Three Rs can be extended to cover these developments. The burgeoning use of GM animals in science calls for new forms of reduction through improved genetic modification technology, plus continued attention to alternative approaches and cost-benefit analyses that include the large numbers of animals involved indirectly. The adoption of more expanded definitions of refinement that go beyond minimising distress will capture concerns for enhancing the quality of life of animals through improved husbandry and handling. Targeting refinement to the unpredictable effects of gene modification may be difficult; in these cases, careful attention to monitoring and endpoints are the obvious options. Refinement can also include sharing data about the welfare impacts of gene modifications, and modelling earlier stages of disease, in order to reduce the potential suffering caused to disease models. Other issues may require a move beyond the Three Rs. Certain levels of harm, or numbers and use of certain species, may be unacceptable, regardless of potential benefits. This can be addressed by supplementing the utilitarian basis of the Three Rs with principles based on deontological and relational ethics. The Three Rs remain very useful, but they require thoughtful interpretation and expansion in order for Animal Ethics Committees to address the full range of issues in animal-based research.

Six principles to enhance health workforce flexibility.

PubMed

Nancarrow, Susan A

2015-04-07

This paper proposes approaches to break down the boundaries that reduce the ability of the health workforce to respond to population needs, or workforce flexibility. Accessible health services require sufficient numbers and types of skilled workers to meet population needs. However, there are several reasons that the health workforce cannot or does not meet population needs. These primarily stem from workforce shortages. However, the health workforce can also be prevented from responding appropriately and efficiently because of restrictions imposed by professional boundaries, funding models or therapeutic partitions. These boundaries limit the ability of practitioners to effectively diagnose and treat patients by restricting access to specific skills, technologies and services. In some cases, these boundaries not only reduce workforce flexibility, but they introduce inefficiencies in the form of additional clinical transactions and costs, further detracting from workforce responsiveness. Several new models of care are being developed to enhance workforce flexibility by enabling existing staff to work to their full scope of practice, extend their roles or by introducing new workers. Expanding on these concepts, this theoretical paper proposes six principles that have the potential to enhance health workforce flexibility, specifically: 1. Measure health system performance from the perspective of the patient. 2. Minimise training times. 3. Regulate tasks (competencies), not professions. 4. Match rewards and indemnity to the levels of skill and risk required to perform a particular task, not professional title. 5. Ensure that practitioners have all the skills they need to perform the tasks required to work in the environment in which they work 6. Enable practitioners to work to their full scope of practice delegate tasks where required These proposed principles will challenge some of the existing social norms around health-care delivery; however, many of these principles are already being applied, albeit on a small scale. This paper discusses the implications of these reforms. 1. Is person-centred care at odds with professional monopolies? 2. Should the state regulate professions and, by doing so, protect professional monopolies or, instead, regulate tasks or competencies? 3. Can health-care efficiency be enhanced by reducing the number of clinical transactions required to meet patient needs?

Influence of the Pauli exclusion principle and the polarization of nuclei on the nuclear part of the interaction potential in the 40Ca +40Ca system

NASA Astrophysics Data System (ADS)

Nesterov, V. O.

2018-06-01

In the framework of the energy density method with the use of the wave function of the two-center shell model, the influence of the simultaneous account for the Pauli exclusion principle and the monopole and quadrupole polarizations of nuclei on the nuclear part of the potential of their interaction by the example of the 40Ca +40Ca system is considered. The calculations performed in the framework of the adiabatic approximation show that the consideration of the Pauli exclusion principle and the polarization of nuclei, especially the quadrupole one, essentially affects the nucleus-nucleus interaction potential.

Cost Finding Principles and Procedures. Preliminary Field Review Edition. Technical Report 26.

ERIC Educational Resources Information Center

Ziemer, Gordon; And Others

This report is part of the Larger Cost Finding Principles Project designed to develop a uniform set of standards, definitions, and alternative procedures that will use accounting and statistical data to find the full cost of resources utilized in the process of producing institutional outputs. This technical report describes preliminary procedures…

Launching a Principal Preparation Program for High Needs Rural Schools

ERIC Educational Resources Information Center

Pijanowski, John C.; Peer, Diana K.

2016-01-01

This paper describes the first two years of planning and launching a full scholarship principal preparation program aimed at developing leaders to work in poor rural schools throughout Arkansas. The founding principles that guided the program are explored as well as how those principles were challenged and retained from the initial proposal…

Full time adult credential students' instructional preferences at California State University, Long Beach: pedagogy orandragogy?

PubMed

Wang, Victor

2004-03-01

This study investigated the instructional preferences of full time adult credential students after they took a live course called Principles of Adult Education at California State University, Long Beach (CSULB) in the fall semester of 2002. These full time adult credential students had been working on their adult teaching credentials to meet the competencies specified by the California Commission on Teacher Credentialing. The course introduced students to Andragogy developed by Malcolm Knowles out of the andragogical model developed by Lindeman (1926). The study used Principles of Adult Learning Scales (PALS), advanced by Gary Conti in 1983 to measure instructional preferences. Data were collected from 30 (100% of 30) full time adult credential students enrolled in a live course to determine their instructional preferences of helping adults learn. The results of the study showed in most cases these adult learning professionals taught adult students andragogically; in some cases they taught adult students pedagogically.

Coupled structural, thermal, phase-change and electromagnetic analysis for superconductors, volume 2

NASA Technical Reports Server (NTRS)

Felippa, Carlos A.; Farhat, Charbel; Park, K. C.; Militello, Carmelo; Schuler, James J.

1993-01-01

Two families of parametrized mixed variational principles for linear electromagnetodynamics are constructed. The first family is applicable when the current density distribution is known a priori. Its six independent fields are magnetic intensity and flux density, magnetic potential, electric intensity and flux density and electric potential. Through appropriate specialization of parameters the first principle reduces to more conventional principles proposed in the literature. The second family is appropriate when the current density distribution and a conjugate Lagrange multiplier field are adjoined, giving a total of eight independently varied fields. In this case it is shown that a conventional variational principle exists only in the time-independent (static) case. Several static functionals with reduced number of varied fields are presented. The application of one of these principles to construct finite elements with current prediction capabilities is illustrated with a numerical example.

Ashley, Two Born as One, and the Best Interests of a Child.

PubMed

Gillett, Grant

2016-01-01

What is in the best interests of a child, and could that ever include interventions that we might regard as prima facie detrimental to a child's physical well-being? This question is raised a fortiori by growth attenuation treatments in children with severe neurological disorders causing extreme developmental delay. I argue that two principles that provide guidance in generating a conception of best interests for each individual child yield the right results in such cases. The principles are as follows: the potentiality principle, whereby every child should be able to develop its potential and is entitled to receive certain help in doing so, and the principle of psychosomatic harmony, whereby every human being is entitled to treatment that is appropriate to or enables a life in which mind and body are in tune with each other. These principles indicate a certain response to what we can call Ashley-type cases and admit certain caveats.

Sequential chemical-biological processes for the treatment of industrial wastewaters: review of recent progresses and critical assessment.

PubMed

Guieysse, Benoit; Norvill, Zane N

2014-02-28

When direct wastewater biological treatment is unfeasible, a cost- and resource-efficient alternative to direct chemical treatment consists of combining biological treatment with a chemical pre-treatment aiming to convert the hazardous pollutants into more biodegradable compounds. Whereas the principles and advantages of sequential treatment have been demonstrated for a broad range of pollutants and process configurations, recent progresses (2011-present) in the field provide the basis for refining assessment of feasibility, costs, and environmental impacts. This paper thus reviews recent real wastewater demonstrations at pilot and full scale as well as new process configurations. It also discusses new insights on the potential impacts of microbial community dynamics on process feasibility, design and operation. Finally, it sheds light on a critical issue that has not yet been properly addressed in the field: integration requires complex and tailored optimization and, of paramount importance to full-scale application, is sensitive to uncertainty and variability in the inputs used for process design and operation. Future research is therefore critically needed to improve process control and better assess the real potential of sequential chemical-biological processes for industrial wastewater treatment. Copyright © 2013 Elsevier B.V. All rights reserved.

IoT-Forensics Meets Privacy: Towards Cooperative Digital Investigations

PubMed Central

Lopez, Javier

2018-01-01

IoT-Forensics is a novel paradigm for the acquisition of electronic evidence whose operation is conditioned by the peculiarities of the Internet of Things (IoT) context. As a branch of computer forensics, this discipline respects the most basic forensic principles of preservation, traceability, documentation, and authorization. The digital witness approach also promotes such principles in the context of the IoT while allowing personal devices to cooperate in digital investigations by voluntarily providing electronic evidence to the authorities. However, this solution is highly dependent on the willingness of citizens to collaborate and they may be reluctant to do so if the sensitive information within their personal devices is not sufficiently protected when shared with the investigators. In this paper, we provide the digital witness approach with a methodology that enables citizens to share their data with some privacy guarantees. We apply the PRoFIT methodology, originally defined for IoT-Forensics environments, to the digital witness approach in order to unleash its full potential. Finally, we show the feasibility of a PRoFIT-compliant digital witness with two use cases. PMID:29414864

First principles study of the ground state properties of Si, Ga, and Ge doped Fe50Al50

NASA Astrophysics Data System (ADS)

Pérez, Carlos Ariel Samudio; dos Santos, Antonio Vanderlei

2018-06-01

The first principles calculation of the structural, electronic and associated properties of the Fe50Al50 alloy (B2 phase) doped by s-p elements (Im = Si, Ga, and Ge) are performed as a function of the atomic concentration on the basis of the Full Potential Linear Augmented Plane Wave (FP-LAPW) method as implemented in the WIEN2k code. The Al substitution by Im (Si and Ge) atoms (principally at a concentration of 6.25 at%) induces a pronounced redistribution of the electronic charge leading to a strong Fe-Im interaction with covalent bonding character. At the same time, decrease the lattice volume (V) while increase the bulk modulus (B). For the alloys containing Ga, the Fe-Ga interaction is also observed but the V and B of the alloy are very near to that of pure Fe-Al alloy. The magnetic moment and hyperfine parameters observed at the lattice sites of studied alloys also show variations, they increase or decrease in relation to that in Fe50Al50 according to the Im that substitutes Al.

IoT-Forensics Meets Privacy: Towards Cooperative Digital Investigations.

PubMed

Nieto, Ana; Rios, Ruben; Lopez, Javier

2018-02-07

IoT-Forensics is a novel paradigm for the acquisition of electronic evidence whose operation is conditioned by the peculiarities of the Internet of Things (IoT) context. As a branch of computer forensics, this discipline respects the most basic forensic principles of preservation, traceability, documentation, and authorization. The digital witness approach also promotes such principles in the context of the IoT while allowing personal devices to cooperate in digital investigations by voluntarily providing electronic evidence to the authorities. However, this solution is highly dependent on the willingness of citizens to collaborate and they may be reluctant to do so if the sensitive information within their personal devices is not sufficiently protected when shared with the investigators. In this paper, we provide the digital witness approach with a methodology that enables citizens to share their data with some privacy guarantees. We apply the PRoFIT methodology, originally defined for IoT-Forensics environments, to the digital witness approach in order to unleash its full potential. Finally, we show the feasibility of a PRoFIT-compliant digital witness with two use cases.

Thermal Conductivities in Solids from First Principles: Accurate Computations and Rapid Estimates

NASA Astrophysics Data System (ADS)

Carbogno, Christian; Scheffler, Matthias

In spite of significant research efforts, a first-principles determination of the thermal conductivity κ at high temperatures has remained elusive. Boltzmann transport techniques that account for anharmonicity perturbatively become inaccurate under such conditions. Ab initio molecular dynamics (MD) techniques using the Green-Kubo (GK) formalism capture the full anharmonicity, but can become prohibitively costly to converge in time and size. We developed a formalism that accelerates such GK simulations by several orders of magnitude and that thus enables its application within the limited time and length scales accessible in ab initio MD. For this purpose, we determine the effective harmonic potential occurring during the MD, the associated temperature-dependent phonon properties and lifetimes. Interpolation in reciprocal and frequency space then allows to extrapolate to the macroscopic scale. For both force-field and ab initio MD, we validate this approach by computing κ for Si and ZrO2, two materials known for their particularly harmonic and anharmonic character. Eventually, we demonstrate how these techniques facilitate reasonable estimates of κ from existing MD calculations at virtually no additional computational cost.

First-principle calculations of structural, electronic, optical, elastic and thermal properties of MgXAs2 (X=Si, Ge) compounds

NASA Astrophysics Data System (ADS)

Cheddadi, S.; Boubendira, K.; Meradji, H.; Ghemid, S.; Hassan, F. El Haj; Lakel, S.; Khenata, R.

2017-12-01

First-principle calculations on the structural, electronic, optical, elastic and thermal properties of the chalcopyrite MgXAs2 (X=Si, Ge) have been performed within the density functional theory (DFT) using the full-potential linearized augmented plane wave (FP-LAPW) method. The obtained equilibrium structural parameters are in good agreement with the available experimental data and theoretical results. The calculated band structures reveal a direct energy band gap for the interested compounds. The predicted band gaps using the modified Becke-Johnson (mBJ) exchange approximation are in fairly good agreement with the experimental data. The optical constants such as the dielectric function, refractive index, and the extinction coefficient are calculated and analysed. The independent elastic parameters namely, C_{11}, C_{12}, C_{13}, C_{33}, C_{44} and C_{66 } are evaluated. The effects of temperature and pressure on some macroscopic properties of MgSiAs2 and MgGeAs2 are predicted using the quasiharmonic Debye model in which the lattice vibrations are taken into account.

Implementation and benchmark of a long-range corrected functional in the density functional based tight-binding method

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

Lutsker, V.; Niehaus, T. A., E-mail: thomas.niehaus@physik.uni-regensburg.de; Aradi, B.

2015-11-14

Bridging the gap between first principles methods and empirical schemes, the density functional based tight-binding method (DFTB) has become a versatile tool in predictive atomistic simulations over the past years. One of the major restrictions of this method is the limitation to local or gradient corrected exchange-correlation functionals. This excludes the important class of hybrid or long-range corrected functionals, which are advantageous in thermochemistry, as well as in the computation of vibrational, photoelectron, and optical spectra. The present work provides a detailed account of the implementation of DFTB for a long-range corrected functional in generalized Kohn-Sham theory. We apply themore » method to a set of organic molecules and compare ionization potentials and electron affinities with the original DFTB method and higher level theory. The new scheme cures the significant overpolarization in electric fields found for local DFTB, which parallels the functional dependence in first principles density functional theory (DFT). At the same time, the computational savings with respect to full DFT calculations are not compromised as evidenced by numerical benchmark data.« less

Basic space payload fastener

NASA Technical Reports Server (NTRS)

Vranish, J. M.; Gorevan, Stephen

1995-01-01

A new basic space fastener has been developed and tested by the GSFC. The purposes of this fastener are to permit assembly and servicing in space by astronauts and/or robots and to facilitate qualification of payloads on Earth prior to launch by saving time and money during the systems integration and component testing and qualification processes. The space fastener is a rework of the basic machine screw such that crossthreading is impossible; it is self-locking and will not work its way out during launch (vibration proof); it will not wear out despite repeated use; it occupies a small foot print which is comparable to its machine screw equivalent, and it provides force and exhibits strength comparable to its machine screw equivalent. Construction is ultra-simple and cost effective and the principle is applicable across the full range of screw sizes ranging from a #10 screw to 2.5 cm (1 in) or more. In this paper, the fastener principles of operation will be discussed along with test results and construction details. The new fastener also has considerable potential in the commercial sector. A few promising applications will be presented.

First-Principles Study on the Structural and Magnetic Properties of Iron Hydride

NASA Astrophysics Data System (ADS)

Tsumuraya, Takao; Matsuura, Yasuyuki; Shishidou, Tatsuya; Oguchi, Tamio

2012-06-01

The magnetic and structural properties of iron hydride FeH with the double hexagonal close-packed (dhcp) and hexagonal close-packed (hcp) structures are investigated by first-principles density-functional theory calculations with a spin-polarized form of generalized gradient approximation. All the calculations are performed using all-electron full-potential linearized augmented plane wave method. Both dhcp and hcp FeH are ferromagnetic at ambient pressure. The ferromagnetic ordering of the dhcp structure collapses at a pressure of 48 GPa, while that of the hcp structure vanishes gradually from 48 GPa. The modification in the density of states (DOS) due to the applied pressure causes the collapse of the magnetization. The difference in magnetic moment reduction between dhcp and hcp FeH is attributed to their DOS around the Fermi level. The calculated magnetocrystalline anisotropy energies between in-plane and out-of-plane spin orientations are found to be 124 μeV/Fe for the dhcp structure, and 100 μeV/Fe for the hcp structure. The easy axis is in-plane direction for both structures.

Toward ethical norms and institutions for climate engineering research

NASA Astrophysics Data System (ADS)

Morrow, David R.; Kopp, Robert E.; Oppenheimer, Michael

2009-10-01

Climate engineering (CE), the intentional modification of the climate in order to reduce the effects of increasing greenhouse gas concentrations, is sometimes touted as a potential response to climate change. Increasing interest in the topic has led to proposals for empirical tests of hypothesized CE techniques, which raise serious ethical concerns. We propose three ethical guidelines for CE researchers, derived from the ethics literature on research with human and animal subjects, applicable in the event that CE research progresses beyond computer modeling. The Principle of Respect requires that the scientific community secure the global public's consent, voiced through their governmental representatives, before beginning any empirical research. The Principle of Beneficence and Justice requires that researchers strive for a favorable risk-benefit ratio and a fair distribution of risks and anticipated benefits, all while protecting the basic rights of affected individuals. Finally, the Minimization Principle requires that researchers minimize the extent and intensity of each experiment by ensuring that no experiments last longer, cover a greater geographical extent, or have a greater impact on the climate, ecosystem, or human welfare than is necessary to test the specific hypotheses in question. Field experiments that might affect humans or ecosystems in significant ways should not proceed until a full discussion of the ethics of CE research occurs and appropriate institutions for regulating such experiments are established.

Structural, electronic, elastic, and thermal properties of CaNiH3 perovskite obtained from first-principles calculations

NASA Astrophysics Data System (ADS)

Benlamari, S.; Bendjeddou, H.; Boulechfar, R.; Amara Korba, S.; Meradji, H.; Ahmed, R.; Ghemid, S.; Khenata, R.; Omran, S. Bin

2018-03-01

A theoretical study of the structural, elastic, electronic, mechanical, and thermal properties of the perovskite-type hydride CaNiH3 is presented. This study is carried out via first-principles full potential (FP) linearized augmented plane wave plus local orbital (LAPW+lo) method designed within the density functional theory (DFT). To treat the exchange–correlation energy/potential for the total energy calculations, the local density approximation (LDA) of Perdew–Wang (PW) and the generalized gradient approximation (GGA) of Perdew–Burke–Ernzerhof (PBE) are used. The three independent elastic constants (C 11, C 12, and C 44) are calculated from the direct computation of the stresses generated by small strains. Besides, we report the variation of the elastic constants as a function of pressure as well. From the calculated elastic constants, the mechanical character of CaNiH3 is predicted. Pertaining to the thermal properties, the Debye temperature is estimated from the average sound velocity. To further comprehend this compound, the quasi-harmonic Debye model is used to analyze the thermal properties. From the calculations, we find that the obtained results of the lattice constant (a 0), bulk modulus (B 0), and its pressure derivative ({B}0^{\\prime }) are in good agreement with the available theoretical as well as experimental results. Similarly, the obtained electronic band structure demonstrates the metallic character of this perovskite-type hydride.

Fundamental Principles of Coherent-Feedback Quantum Control

DTIC Science & Technology

2014-12-08

in metrology (acceleration sensing, vibrometry, gravity wave detection) and in quantum information processing (continuous-variables quantum ...AFRL-OSR-VA-TR-2015-0009 FUNDAMENTAL PRINCIPLES OF COHERENT-FEEDBACK QUANTUM CONTROL Hideo Mabuchi LELAND STANFORD JUNIOR UNIV CA Final Report 12/08...foundations and potential applications of coherent-feedback quantum control. We have focused on potential applications in quantum -enhanced metrology and

Atomic and electronic structure of oxygen vacancies and Nb-impurity in SrTiO3

NASA Astrophysics Data System (ADS)

Hamid, A. S.

2009-12-01

We present the results of a first-principle full-potential linearized augmented plane wave (FLAPW) method to study the effect of defects on the electronic structure of SrTiO3. In addition, the relaxation of nearest neighbor atoms around those defects were calculated self-consistently. The calculations were performed using the local (spin) density approximations (L(S)DA), for the exchange-correlation potential. SrTiO3 was found to experience an insulator-to-metal transition upon the formation of oxygen vacancies or the substitution of Nb at the Ti site. The formation of oxygen divacancy disclosed additional states below the conduction band edge. The crystalline lattice relaxation showed displacements of atoms in rather large defective region. The magnitudes of atomic movements, however, were not large, normally not exceeding 0.15 Å. Our results were compared to the available experimental observations.

Comments on the feasibility of developing gas core nuclear reactors. [for manned interplanetary spacecraft propulsion

NASA Technical Reports Server (NTRS)

Rom, F. E.

1969-01-01

Recent developments in the fields of gas core hydrodynamics, heat transfer, and neutronics indicate that gas core nuclear rockets may be feasible from the point of view of basic principles. Based on performance predictions using these results, mission analyses indicate that gas core nuclear rockets may have the potential for reducing the initial weight in orbit of manned interplanetary vehicles by a factor of 5 when compared to the best chemical rocket systems. In addition, there is a potential for reducing total trip times from 450 to 500 days for chemical systems to 250 to 300 days for gas core systems. The possibility of demonstrating the feasibility of gas core nuclear rocket engines by means of a logical series of experiments of increasing difficulty that ends with ground tests of full scale gas core reactors is considered.

Theoretical band structure of the superconducting antiperovskite oxide Sr3-xSnO

NASA Astrophysics Data System (ADS)

Ikeda, Atsutoshi; Fukumoto, Toshiyuki; Oudah, Mohamed; Hausmann, Jan Niklas; Yonezawa, Shingo; Kobayashi, Shingo; Sato, Masatoshi; Tassel, Cédric; Takeiri, Fumitaka; Takatsu, Hiroshi; Kageyama, Hiroshi; Maeno, Yoshiteru

2018-05-01

In order to investigate the position of the strontium deficiency in superconductive Sr3-xSnO, we synthesized and measured X-ray-diffraction patterns of Sr3-xSnO (x ∼ 0.5). Because no clear peaks originating from superstructures were observed, strontium deficiency is most likely to be randomly distributed. We also performed first-principles band-structure calculations on Sr3-xSnO (x = 0, 0.5) using two methods: full-potential linearized-augmented plane-wave plus local orbitals method and the Korringa-Kohn-Rostoker Green function method combined with the coherent potential approximation. We revealed that the Fermi energy of Sr3-xSnO in case of x ∼ 0.5 is about 0.8 eV below the original Fermi energy of the stoichiometric Sr3SnO, where the mixing of the valence p and conduction d orbitals are considered to be small.

Correlation of electronic structure and magnetic moment in Ga1-xMnxN : First-principles, mean field and high temperature series expansions calculations

NASA Astrophysics Data System (ADS)

Masrour, R.; Hlil, E. K.

2016-08-01

Self-consistent ab initio calculations based on density-functional theory and using both full potential linearized augmented plane wave and Korring-Kohn-Rostoker-coherent potential approximation methods, are performed to investigate both electronic and magnetic properties of the Ga1-xMnxN system. Magnetic moments considered to lie along (001) axes are computed. Obtained data from ab initio calculations are used as input for the high temperature series expansions (HTSEs) calculations to compute other magnetic parameters such as the magnetic phase diagram and the critical exponent. The increasing of the dilution x in this system has allowed to verify a series of HTSEs predictions on the possibility of ferromagnetism in dilute magnetic insulators and to demonstrate that the interaction changes from antiferromagnetic to ferromagnetic passing through the spins glace phase.

First-principles study of structural stability, electronic, optical and elastic properties of binary intermetallic: PtZr

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

Pagare, Gitanjali, E-mail: gita-pagare@yahoo.co.in; Jain, Ekta, E-mail: jainekta05@gmail.com; Sanyal, S. P., E-mail: sps.physicsbu@gmail.com

2016-05-06

Structural, electronic, optical and elastic properties of PtZr have been studied using the full-potential linearized augmented plane wave (FP-LAPW) method within density functional theory (DFT). The energy against volume and enthalpy vs. pressure variation in three different structures i.e. B{sub 1}, B{sub 2} and B{sub 3} for PtZr has been presented. The equilibrium lattice parameter, bulk modulus and its pressure derivative have been obtained using optimization method for all the three phases. Furthermore, electronic structure was discussed to reveal the metallic character of the present compound. The linear optical properties are also studied under zero pressure for the first time.more » Results on elastic properties are obtained using generalized gradient approximation (GGA) for exchange correlation potentials. Ductile nature of PtZr compound is predicted in accordance with Pugh’s criteria.« less

Gravitational effective action at second order in curvature and gravitational waves

NASA Astrophysics Data System (ADS)

Calmet, Xavier; Capozziello, Salvatore; Pryer, Daniel

2017-09-01

We consider the full effective theory for quantum gravity at second order in curvature including non-local terms. We show that the theory contains two new degrees of freedom beyond the massless graviton: namely a massive spin-2 ghost and a massive scalar field. Furthermore, we show that it is impossible to fine-tune the parameters of the effective action to eliminate completely the classical spin-2 ghost because of the non-local terms in the effective action. Being a classical field, it is not clear anyway that this ghost is problematic. It simply implies a repulsive contribution to Newton's potential. We then consider how to extract the parameters of the effective action and show that it is possible to measure, at least in principle, the parameters of the local terms independently of each other using a combination of observations of gravitational waves and measurements performed by pendulum type experiments searching for deviations of Newton's potential.

Bioenergetics

PubMed Central

2008-01-01

Natural life is chemical. Chemistry, not abstract logic, determines and constrains its potentialities. One of the potentialities is cognition. Humans have two equivalent cognitive systems: the immune and the nervous ones. The principle of functioning is the same for both: rooted in the previously acquired and embodied knowledge, the system is intrinsically generating many new chemical states and the environment selects and stabilizes appropriate of them. From the fundamental level of complicated brain chemistry (“biochemese”) higher levels emerge: the physiological (“physiologese”) and the mental (“mentalese”). Processes are causal at the basic chemical level; they are mere isomorphic, tautological translations at the other levels. The thermodynamic necessity to maintain correlations in the complicated chemical system and to generate variants makes the nervous system energetically expensive: it runs continuously at full speed and external inputs only trigger and modulate the ongoing dynamics. Models of the brain as a universal computer are utterly inadequate. PMID:19513208

Patching the Exchange-Correlation Potential in Density Functional Theory.

PubMed

Huang, Chen

2016-05-10

A method for directly patching exchange-correlation (XC) potentials in materials is derived. The electron density of a system is partitioned into subsystem densities by dividing its Kohn-Sham (KS) potential among the subsystems. Inside each subsystem, its projected KS potential is required to become the total system's KS potential. This requirement, together with the nearsightedness principle of electronic matters, ensures that the electronic structures inside subsystems can be good approximations to the total system's electronic structure. The nearsightedness principle also ensures that subsystem densities could be well localized in their regions, making it possible to use high-level methods to invert the XC potentials for subsystem densities. Two XC patching methods are developed. In the local XC patching method, the total system's XC potential is improved in the cluster region. We show that the coupling between a cluster and its environment is important for achieving a fast convergence of the electronic structure in the cluster region. In the global XC patching method, we discuss how to patch the subsystem XC potentials to construct the XC potential in the total system, aiming to scale up high-level quantum mechanics simulations of materials. Proof-of-principle examples are given.

Ground-state densities from the Rayleigh-Ritz variation principle and from density-functional theory.

PubMed

Kvaal, Simen; Helgaker, Trygve

2015-11-14

The relationship between the densities of ground-state wave functions (i.e., the minimizers of the Rayleigh-Ritz variation principle) and the ground-state densities in density-functional theory (i.e., the minimizers of the Hohenberg-Kohn variation principle) is studied within the framework of convex conjugation, in a generic setting covering molecular systems, solid-state systems, and more. Having introduced admissible density functionals as functionals that produce the exact ground-state energy for a given external potential by minimizing over densities in the Hohenberg-Kohn variation principle, necessary and sufficient conditions on such functionals are established to ensure that the Rayleigh-Ritz ground-state densities and the Hohenberg-Kohn ground-state densities are identical. We apply the results to molecular systems in the Born-Oppenheimer approximation. For any given potential v ∈ L(3/2)(ℝ(3)) + L(∞)(ℝ(3)), we establish a one-to-one correspondence between the mixed ground-state densities of the Rayleigh-Ritz variation principle and the mixed ground-state densities of the Hohenberg-Kohn variation principle when the Lieb density-matrix constrained-search universal density functional is taken as the admissible functional. A similar one-to-one correspondence is established between the pure ground-state densities of the Rayleigh-Ritz variation principle and the pure ground-state densities obtained using the Hohenberg-Kohn variation principle with the Levy-Lieb pure-state constrained-search functional. In other words, all physical ground-state densities (pure or mixed) are recovered with these functionals and no false densities (i.e., minimizing densities that are not physical) exist. The importance of topology (i.e., choice of Banach space of densities and potentials) is emphasized and illustrated. The relevance of these results for current-density-functional theory is examined.

The meaning of the EPSRC principles of robotics

NASA Astrophysics Data System (ADS)

Bryson, Joanna J.

2017-04-01

In revisiting the Principles of Robotics (as we do in this special issue), it is important to carefully consider their full meaning - their history, the intentions behind them, and their actual societal impact to date. Here I address first the meaning of the document as a whole, then of its constituent parts. Further, I describe the nature of policy, and use the Principles as a case study to discuss how government and academia can interact in constructing policy. I defend the Principles and their main themes: that commercially manufactured robots should not be responsible parties under the law, and that users should not be deceived about robots' capacities or moral status. This perspective allows for the incorporation of robots immediately into UK society and law - the objective of the Principles. The Principles were not designed for every conceivable robot, but rather serve in part as design specifications for robots to be incorporated as legal products into British society.

Structural, electronic and thermal properties of super hard ternary boride, WAlB

NASA Astrophysics Data System (ADS)

Rajpoot, Priyanka; Rastogi, Anugya; Verma, U. P.

2018-04-01

A first principle study of the structural, electronic and thermal properties of Tungsten Aluminum Boride (WAlB) using full-potential linearized augmented plane wave (FP-LAPW) in the frame work of density function theory (DFT) have been calculated. The calculated equilibrium structural parameters are in excellent agreement with available experimental results. The calculated electronic band structure reveals that WAlB is metallic in nature. The quasi-harmonic Debye model is applied to study of the temperature and pressure effect on volume, Debye temperature, thermal expansion coefficient and specific heat at constant volume and constant pressure. To the best of our knowledge theoretical investigation of these properties of WAlB is reported for the first time.

Review of phase measuring deflectometry

DOE PAGES

Huang, Lei; Idir, Mourad; Zuo, Chao; ...

2018-04-07

As a low cost, full-field three-dimensional shape measurement technique with high dynamic range, Phase Measuring Deflectometry (PMD) has been studied and improved to be a simple and effective manner to inspect specular reflecting surfaces. In this review, the fundamental principle and the basic concepts of PMD technique are introduced and followed by a brief overview of its key developments since it was first proposed. In addition, the similarities and differences compared with other related techniques are discussed to highlight the distinguishing features of the PMD technique. In conclusion, we will address the major challenges, the existing solutions and the remainingmore » limitations in this technique to provide some suggestions for potential future investigations.« less

High-Throughput Thermodynamic Modeling and Uncertainty Quantification for ICME

NASA Astrophysics Data System (ADS)

Otis, Richard A.; Liu, Zi-Kui

2017-05-01

One foundational component of the integrated computational materials engineering (ICME) and Materials Genome Initiative is the computational thermodynamics based on the calculation of phase diagrams (CALPHAD) method. The CALPHAD method pioneered by Kaufman has enabled the development of thermodynamic, atomic mobility, and molar volume databases of individual phases in the full space of temperature, composition, and sometimes pressure for technologically important multicomponent engineering materials, along with sophisticated computational tools for using the databases. In this article, our recent efforts will be presented in terms of developing new computational tools for high-throughput modeling and uncertainty quantification based on high-throughput, first-principles calculations and the CALPHAD method along with their potential propagations to downstream ICME modeling and simulations.

Analysis of superconducting electromagnetic finite elements based on a magnetic vector potential variational principle

NASA Technical Reports Server (NTRS)

Schuler, James J.; Felippa, Carlos A.

1991-01-01

Electromagnetic finite elements are extended based on a variational principle that uses the electromagnetic four potential as primary variable. The variational principle is extended to include the ability to predict a nonlinear current distribution within a conductor. The extension of this theory is first done on a normal conductor and tested on two different problems. In both problems, the geometry remains the same, but the material properties are different. The geometry is that of a 1-D infinite wire. The first problem is merely a linear control case used to validate the new theory. The second problem is made up of linear conductors with varying conductivities. Both problems perform well and predict current densities that are accurate to within a few ten thousandths of a percent of the exact values. The fourth potential is then removed, leaving only the magnetic vector potential, and the variational principle is further extended to predict magnetic potentials, magnetic fields, the number of charge carriers, and the current densities within a superconductor. The new element produces good results for the mean magnetic field, the vector potential, and the number of superconducting charge carriers despite a relatively high system condition number. The element did not perform well in predicting the current density. Numerical problems inherent to this formulation are explored and possible remedies to produce better current predicting finite elements are presented.

HEALTH TECHNOLOGY ASSESSMENT FOR DECISION MAKING IN LATIN AMERICA: GOOD PRACTICE PRINCIPLES.

PubMed

Pichon-Riviere, Andrés; Soto, Natalie C; Augustovski, Federico Ariel; García Martí, Sebastián; Sampietro-Colom, Laura

2018-06-11

The aim of this study was to identify good practice principles for health technology assessment (HTA) that are the most relevant and of highest priority for application in Latin America and to identify potential barriers to their implementation in the region. HTA good practice principles proposed at the international level were identified and then explored during a deliberative process in a forum of assessors, funders, and product manufacturers. Forty-two representatives from ten Latin American countries participated. Good practice principles proposed at the international level were considered valid and potentially relevant to Latin America. Five principles were identified as priority and with the greatest potential to be strengthened at this time: transparency in the production of HTA, involvement of relevant stakeholders in the HTA process, mechanisms to appeal decisions, clear priority-setting processes in HTA, and a clear link between HTA and decision making. The main challenge identified was to find a balance between the application of these principles and the available resources in a way that would not detract from the production of reports and adaptation to the needs of decision makers. The main recommendation was to progress gradually in strengthening HTA and its link to decision making by developing appropriate processes for each country, without trying to impose, in the short-term, standards taken from examples at the international level without adequate adaptation of these to local contexts.

Charge optimized many-body potential for aluminum.

PubMed

Choudhary, Kamal; Liang, Tao; Chernatynskiy, Aleksandr; Lu, Zizhe; Goyal, Anuj; Phillpot, Simon R; Sinnott, Susan B

2015-01-14

An interatomic potential for Al is developed within the third generation of the charge optimized many-body (COMB3) formalism. The database used for the parameterization of the potential consists of experimental data and the results of first-principles and quantum chemical calculations. The potential exhibits reasonable agreement with cohesive energy, lattice parameters, elastic constants, bulk and shear modulus, surface energies, stacking fault energies, point defect formation energies, and the phase order of metallic Al from experiments and density functional theory. In addition, the predicted phonon dispersion is in good agreement with the experimental data and first-principles calculations. Importantly for the prediction of the mechanical behavior, the unstable stacking fault energetics along the [Formula: see text] direction on the (1 1 1) plane are similar to those obtained from first-principles calculations. The polycrsytal when strained shows responses that are physical and the overall behavior is consistent with experimental observations.

77 FR 11778 - Reform of Federal Policies Relating to Grants and Cooperative Agreements; Cost Principles and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-28

... contracts that that are subject to ``full coverage'' under the Cost Accounting Standards (CAS) as defined at... full Single Audit. These Audits would be strengthened per the ideas in reforms 2-5 (below) to give... the full Single Audit for entities expending more than $3 million would ensure that agencies still...

A full-scale STOVL ejector experiment

NASA Technical Reports Server (NTRS)

Barankiewicz, Wendy S.

1993-01-01

The design and development of thrust augmenting short take-off and vertical landing (STOVL) ejectors has typically been an iterative process. In this investigation, static performance tests of a full-scale vertical lift ejector were performed at primary flow temperatures up to 1560 R (1100 F). Flow visualization (smoke generators, yarn tufts and paint dots) was used to assess inlet flowfield characteristics, especially around the primary nozzle and end plates. Performance calculations are presented for ambient temperatures close to 480 R (20 F) and 535 R (75 F) which simulate 'seasonal' aircraft operating conditions. Resulting thrust augmentation ratios are presented as functions of nozzle pressure ratio and temperature. Full-scale experimental tests such as this are expensive, and difficult to implement at engine exhaust temperatures. For this reason the utility of using similarity principles -- in particular, the Munk and Prim similarity principle for isentropic flow -- was explored. At different primary temperatures, exit pressure contours are compared for similarity. A nondimensional flow parameter is then shown to eliminate primary nozzle temperature dependence and verify similarity between the hot and cold flow experiments. Under the assumption that an appropriate similarity principle can be established, then properly chosen performance parameters should be similar for both hot flow and cold flow model tests.

First principles molecular dynamics of molten NaCl

NASA Astrophysics Data System (ADS)

Galamba, N.; Costa Cabral, B. J.

2007-03-01

First principles Hellmann-Feynman molecular dynamics (HFMD) results for molten NaCl at a single state point are reported. The effect of induction forces on the structure and dynamics of the system is studied by comparison of the partial radial distribution functions and the velocity and force autocorrelation functions with those calculated from classical MD based on rigid-ion and shell-model potentials. The first principles results reproduce the main structural features of the molten salt observed experimentally, whereas they are incorrectly described by both rigid-ion and shell-model potentials. Moreover, HFMD Green-Kubo self-diffusion coefficients are in closer agreement with experimental data than those predicted by classical MD. A comprehensive discussion of MD results for molten NaCl based on different ab initio parametrized polarizable interionic potentials is also given.

Conceptualizing strategic environmental assessment: Principles, approaches and research directions

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

Noble, Bram, E-mail: b.noble@usask.ca; Nwanekezie, Kelechi

Increasing emphasis has been placed in recent years on transitioning strategic environmental assessment (SEA) away from its environmental impact assessment (EIA) roots. Scholars have argued the need to conceptualize SEA as a process designed to facilitate strategic thinking, thus enabling transitions toward sustainability. The practice of SEA, however, remains deeply rooted in the EIA tradition and scholars and practitioners often appear divided on the nature and purpose of SEA. This paper revisits the strategic principles of SEA and conceptualizes SEA as a multi-faceted and multi-dimensional assessment process. It is suggested that SEA can be conceptualized as series of approaches operatingmore » along a spectrum from less to more strategic – from impact assessment-based to strategy-based – with each approach to SEA differentiated by the specific objectives of SEA application and the extent to which strategic principles are reflected in its design and implementation. Advancing the effectiveness of SEA requires a continued research agenda focused on improving the traditional SEA approach, as a tool to assess the impacts of policies, plans and programs (PPPs). Realizing the full potential of SEA, however, requires a new research agenda — one focused on the development and testing of a deliberative governance approach to SEA that can facilitate strategic innovations in PPP formulation and drive transitions in short-term policy and initiatives based on longer-term thinking. - Highlights: • SEA facilitates strategic thinking, enabling transitions toward sustainability. • SEA is conceptualized as a spectrum of approaches, from IA-based to strategy-based. • Each approach variably emphasizes strategic principles in its design and practice. • There is no one conceptualization of SEA that is best, SEA is fit for PPP purpose. • Research is needed to advance SEA to facilitate strategic PPP transformations.« less

Virtual Worlds; Real Learning: Design Principles for Engaging Immersive Environments

NASA Technical Reports Server (NTRS)

Wu (u. Sjarpm)

2012-01-01

The EMDT master's program at Full Sail University embarked on a small project to use a virtual environment to teach graduate students. The property used for this project has evolved our several iterations and has yielded some basic design principles and pedagogy for virtual spaces. As a result, students are emerging from the program with a better grasp of future possibilities.

Six Increasingly Higher Levels of Wellness Based on Holistic Principles and Risk Factor Science.

ERIC Educational Resources Information Center

Cassel, Russell N.

1987-01-01

Describes program for achievement of higher wellness levels based on holistic principles and risk factor science. Levels focus on (1) heart disease risk factors and how to reverse them; (2) unconscious needs at conflict with one's conscious goals; (3) identity status, meaning to love and to be loved; (4) autogenics; and (5) full ego development…

Combating Obesity in the Beginning: Incorporating Wellness and Exercise Principles in Teacher Education Programs

ERIC Educational Resources Information Center

Cavallini, M. Felicia; Wendt, Janice C.; Rice, Desmond

2007-01-01

Schools have the potential to foster healthy behaviors among youths through sound health and physical education programs. Teacher candidates who are being certified through teacher preparation programs should take a course on basic wellness and exercise principles, in order to prepare themselves to teach those principles to all school faculty…

Design principles and operating principles: the yin and yang of optimal functioning.

PubMed

Voit, Eberhard O

2003-03-01

Metabolic engineering has as a goal the improvement of yield of desired products from microorganisms and cell lines. This goal has traditionally been approached with experimental biotechnological methods, but it is becoming increasingly popular to precede the experimental phase by a mathematical modeling step that allows objective pre-screening of possible improvement strategies. The models are either linear and represent the stoichiometry and flux distribution in pathways or they are non-linear and account for the full kinetic behavior of the pathway, which is often significantly effected by regulatory signals. Linear flux analysis is simpler and requires less input information than a full kinetic analysis, and the question arises whether the consideration of non-linearities is really necessary for devising optimal strategies for yield improvements. The article analyzes this question with a generic, representative pathway. It shows that flux split ratios, which are the key criterion for linear flux analysis, are essentially sufficient for unregulated, but not for regulated branch points. The interrelationships between regulatory design on one hand and optimal patterns of operation on the other suggest the investigation of operating principles that complement design principles, like a user's manual complements the hardwiring of electronic equipment.

Aerodynamic Analysis of the Truss-Braced Wing Aircraft Using Vortex-Lattice Superposition Approach

NASA Technical Reports Server (NTRS)

Ting, Eric Bi-Wen; Reynolds, Kevin Wayne; Nguyen, Nhan T.; Totah, Joseph J.

2014-01-01

The SUGAR Truss-BracedWing (TBW) aircraft concept is a Boeing-developed N+3 aircraft configuration funded by NASA ARMD FixedWing Project. This future generation transport aircraft concept is designed to be aerodynamically efficient by employing a high aspect ratio wing design. The aspect ratio of the TBW is on the order of 14 which is significantly greater than those of current generation transport aircraft. This paper presents a recent aerodynamic analysis of the TBW aircraft using a conceptual vortex-lattice aerodynamic tool VORLAX and an aerodynamic superposition approach. Based on the underlying linear potential flow theory, the principle of aerodynamic superposition is leveraged to deal with the complex aerodynamic configuration of the TBW. By decomposing the full configuration of the TBW into individual aerodynamic lifting components, the total aerodynamic characteristics of the full configuration can be estimated from the contributions of the individual components. The aerodynamic superposition approach shows excellent agreement with CFD results computed by FUN3D, USM3D, and STAR-CCM+.

Parallelization of the FLAPW method and comparison with the PPW method

NASA Astrophysics Data System (ADS)

Canning, Andrew; Mannstadt, Wolfgang; Freeman, Arthur

2000-03-01

The FLAPW (full-potential linearized-augmented plane-wave) method is one of the most accurate first-principles methods for determining electronic and magnetic properties of crystals and surfaces. In the past the FLAPW method has been limited to systems of about a hundred atoms due to the lack of an efficient parallel implementation to exploit the power and memory of parallel computers. In this work we present an efficient parallelization of the method by division among the processors of the plane-wave components for each state. The code is also optimized for RISC (reduced instruction set computer) architectures, such as those found on most parallel computers, making full use of BLAS (basic linear algebra subprograms) wherever possible. Scaling results are presented for systems of up to 686 silicon atoms and 343 palladium atoms per unit cell running on up to 512 processors on a Cray T3E parallel supercomputer. Some results will also be presented on a comparison of the plane-wave pseudopotential method and the FLAPW method on large systems.

Structure and symmetry inform gating principles of ionotropic glutamate receptors.

PubMed

Zhu, Shujia; Gouaux, Eric

2017-01-01

Ionotropic glutamate receptors (iGluRs) transduce signals derived from release of the excitatory neurotransmitter glutamate from pre-synaptic neurons into excitation of post-synaptic neurons on a millisecond time-scale. In recent years, the elucidation of full-length iGluR structures of NMDA, AMPA and kainate receptors by X-ray crystallography and single particle cryo-electron microscopy has greatly enhanced our understanding of the interrelationships between receptor architecture and gating mechanism. Here we briefly review full-length iGluR structures and discuss the similarities and differences between NMDA receptors and non-NMDA iGluRs. We focus on distinct conformations, including ligand-free, agonist-bound active, agonist-bound desensitized and antagonist-bound conformations as well as modulator and auxiliary protein-bound states. These findings provide insights into structure-based mechanisms of iGluR gating and modulation which together shape the amplitude and time course of the excitatory postsynaptic potential. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'. Copyright © 2016 Elsevier Ltd. All rights reserved.

Managing the physics of the economics of integrated health care.

PubMed

Zismer, Daniel K; Werner, Mark J

2012-01-01

The physics metaphor, as applied to the economics (and financial performance) of the integrated health system, seems appropriate when considered together with the nine principles of management framework provided. The nature of the integrated design enhances leaders' management potential as they consider organizational operations and strategy in the markets ahead. One question begged by this argument for the integrated design is the durability, efficiency and ultimate long-term survivability of the more "traditional" community health care delivery models, which, by design, are fragmented, internally competitive and less capital efficient. They also cannot exploit the leverage of teams, optimal access management or the pursuit of revenues made available in many forms. For those who wish to move from the traditional to the more integrated community health system designs (especially those who have not yet started the journey), the path requires: * Sufficient balance sheet capacity to fund the integration process-especially as the model requires physician practice acquisitions and electronic health record implementations * A well-prepared board13, 14 * A functional, durable and sustainable physician services enterprise design * A redesigned organizational and governance structure * Favorable internal financial incentives alignment design * Effective accountable physician leadership * Awareness that the system is not solely a funding strategy for acquired physicians, rather a fully -.. committed clinical and business model, one in which patient-centered integrated care is the core service (and not acute care hospital-based services) A willingness to create and exploit the implied and inherent potential of an integrated design and unified brand Last, it's important to remember that an integrated health system is a tool that creates a "new potential" (a physics metaphor reference, one last time). The design doesn't operate itself. Application of the management principles presented here are necessary as a complete recipe. Leaders of health systems moving toward integration are cautioned to apply the recipe in full. This article ends with two questions. First, if not an integrated model of health care, what's the alternative? Since it seems clear that many of the existing community-based models are excessively fragmented and inefficient, especially in a reforming U.S. health care marketplace, is there a new model that is superior to the integrated models and, if so, what is it and what are its functional principles? The second question: Is there more than one functional form of integration? This article argues for the most integrated form. Others would argue that clinical integration is sufficient,'s and full integration isn't required. The stability, durability and adaptability of the fully integrated models have, arguably, been tested. The lesser integrated models remain to be proven in an unstable health care marketplace seeking higher levels of economic efficiency.

Finite element analysis of time-independent superconductivity. Ph.D. Thesis Final Report

NASA Technical Reports Server (NTRS)

Schuler, James J.

1993-01-01

The development of electromagnetic (EM) finite elements based upon a generalized four-potential variational principle is presented. The use of the four-potential variational principle allows for downstream coupling of EM fields with the thermal, mechanical, and quantum effects exhibited by superconducting materials. The use of variational methods to model an EM system allows for a greater range of applications than just the superconducting problem. The four-potential variational principle can be used to solve a broader range of EM problems than any of the currently available formulations. It also reduces the number of independent variables from six to four while easily dealing with conductor/insulator interfaces. This methodology was applied to a range of EM field problems. Results from all these problems predict EM quantities exceptionally well and are consistent with the expected physical behavior.

Chemical Principles Exemplified

ERIC Educational Resources Information Center

Plumb, Robert C.

1972-01-01

Collection of two short descriptions of chemical principles seen in life situations: the autocatalytic reaction seen in the bombardier beetle, and molecular potential energy used for quick roasting of beef. Brief reference is also made to methanol lighters. (PS)

On Large Time Behavior and Selection Principle for a Diffusive Carr-Penrose Model

NASA Astrophysics Data System (ADS)

Conlon, Joseph G.; Dabkowski, Michael; Wu, Jingchen

2016-04-01

This paper is concerned with the study of a diffusive perturbation of the linear LSW model introduced by Carr and Penrose. A main subject of interest is to understand how the presence of diffusion acts as a selection principle, which singles out a particular self-similar solution of the linear LSW model as determining the large time behavior of the diffusive model. A selection principle is rigorously proven for a model which is a semiclassical approximation to the diffusive model. Upper bounds on the rate of coarsening are also obtained for the full diffusive model.

Why should the baby live? Human right to life and the precautionary principle.

PubMed

Rocchi, Benedetto

2013-05-01

This paper discusses the issue of 'post-birth abortion' from an applied perspective. Three hypothetical situations where a newborn considered as a 'potential person' is at risk of being killed are proposed to highlight the potential controversial outcomes of post-birth abortion. The internal consistency of the argument proposed by Giubilini and Minerva to morally justify newborn killing is contested as well. Finally, an alternative moral strategy based on the precautionary principle and excluding any distinction between potential and actual persons is proposed as rational.

Advancing Competency-Based Medical Education: A Charter for Clinician-Educators.

PubMed

Carraccio, Carol; Englander, Robert; Van Melle, Elaine; Ten Cate, Olle; Lockyer, Jocelyn; Chan, Ming-Ka; Frank, Jason R; Snell, Linda S

2016-05-01

The International Competency-Based Medical Education (ICBME) Collaborators have been working since 2009 to promote understanding of competency-based medical education (CBME) and accelerate its uptake worldwide. This article presents a charter, supported by a literature-based rationale, which is meant to provide a shared mental model of CBME that will serve as a path forward in its widespread implementation.At a 2013 summit, the ICBME Collaborators laid the groundwork for this charter. Here, the fundamental principles of CBME and professional responsibilities of medical educators in its implementation process are described. The authors outline three fundamental principles: (1) Medical education must be based on the health needs of the populations served; (2) the primary focus of education and training should be the desired outcomes for learners rather than the structure and process of the educational system; and (3) the formation of a physician should be seamless across the continuum of education, training, and practice.Building on these principles, medical educators must demonstrate commitment to teaching, assessing, and role modeling the range of identified competencies. In the clinical setting, they must provide supervision that balances patient safety with the professional development of learners, being transparent with stakeholders about level of supervision needed. They must use effective and efficient assessment strategies and tools for basing transition decisions on competence rather than time in training, empowering learners to be active participants in their learning and assessment. Finally, advancing CBME requires program evaluation and research, faculty development, and a collaborative approach to realize its full potential.

Structural, electronic and magnetic properties of Pr-based filled skutterudites: A first principle study

NASA Astrophysics Data System (ADS)

Yadav, Priya; Nautiyal, Shashank; Verma, U. P.

2018-04-01

Ternary skutterudites materials exhibit good electronic properties due to the unpaired d- and f- electrons of the transition and rare-earth metals, respectively. In this communication, we have performed the structural optimization of Pr-based filled skutterudite (PrCo4P12) for the first time and obtained the electronic band structure, density of states and magnetic moments by using the full-potential linearized augmented plane wave (FP-LAPW) method based on density functional theory (DFT). Our obtained magnetic moment of PrCo4P12 is ˜ 1.8 µB in which main contribution is due to Pr atom. Behavior of this material is metallic and it is most stable in body centered cubic (BCC) structure.

Diagnostics of oral lichen planus based on analysis of volatile organic compounds in saliva

NASA Astrophysics Data System (ADS)

Kistenev, Yury; Borisov, Alexey; Shapovalov, Alexander; Baydik, Olga; Titarenko, Maria

2017-03-01

The ability of diagnostics of oral lichen planus (OLP) based on spectral analysis of saliva using the THz spectroscopy is presented. The study included 8 patients with clinically proven OLP. The comparison group consisted of 8 healthy volunteers. Absorption spectra of the saliva was measured using time-domain spectrometer T-spec (EXPLA) in the range 0.2-3THz and have been considered as the feature vectors of the state. The spatial distribution of the objects under study in the feature space was analyzed using principle component analysis. The groups under study were shown to separate in full. Thus, the saliva analysis by the THz spectroscopy technique can be potentially used as a method of noninvasive diagnostics of the OLP.

Lattice stability and thermal properties of Fe2VAl and Fe2TiSn Heusler compounds

NASA Astrophysics Data System (ADS)

Shastri, Shivprasad S.; Pandey, Sudhir K.

2018-04-01

Fe2VAl and Fe2TiSn are two full-Heusler compounds with non-magnetic ground states. They have application as potential thermoelectric materials. Along with first-principles electronic structure calculations, phonon calculation is one of the important tools in condensed matter physics and material science. Phonon calculations are important in understanding mechanical properties, thermal properties and phase transitions of periodic solids. A combination of electronic structure code and phonon calculation code - phonopy is employed in this work. The vibrational spectra, phonon DOS and thermal properties are studied for these two Heusler compounds. Two compounds are found to be dynamically stable with absence of negative frequencies (energy) in the phonon band structure.

AB INITIO Investigations of the Magnetism in Diluted Magnetic Semiconductor Fe-DOPED GaN

NASA Astrophysics Data System (ADS)

Cheng, Jie; Zhou, Jing; Xu, Wei; Dong, Peng

2014-01-01

In this paper, we present a first principle investigation on Fe-doped GaN with wurtzite and zinc-blend structure using full potential density functional calculations. Data point out that the magnetic behavior of Fe-doped GaN system is strongly dependent on Fe doping configurations. In agreement with the experimental reports, and independently by doping, antiferromagnetism occurs in the zinc-blend structure, while in the wurtzite structure ferromagnetism depends on the Fe doping configurations. Detailed analyses combined with density of state calculations support the assignment that the ferromagnetism is closely related to the impurity band at the origin of the hybridization of Fe 3d and N 2p states in the Fe-doped GaN of wurtzite phase.

Intrahemispheric white matter asymmetries: the missing link between brain structure and functional lateralization?

PubMed

Ocklenburg, Sebastian; Friedrich, Patrick; Güntürkün, Onur; Genç, Erhan

2016-07-01

Hemispheric asymmetries are a central principle of nervous system architecture and shape the functional organization of most cognitive systems. Structural gray matter asymmetries and callosal interactions have been identified as contributing neural factors but always fell short to constitute a full explanans. Meanwhile, recent advances in in vivo white matter tractography have unrevealed the asymmetrical organization of many intrahemispheric white matter pathways, which might serve as the missing link to explain the substrate of functional lateralization. By taking into account callosal interactions, gray matter asymmetries and asymmetrical interhemispheric pathways, we opt for a new triadic model that has the potential to explain many observations which cannot be elucidated within the current frameworks of lateralized cognition.

Hybrid Scheme for Modeling Local Field Potentials from Point-Neuron Networks.

PubMed

Hagen, Espen; Dahmen, David; Stavrinou, Maria L; Lindén, Henrik; Tetzlaff, Tom; van Albada, Sacha J; Grün, Sonja; Diesmann, Markus; Einevoll, Gaute T

2016-12-01

With rapidly advancing multi-electrode recording technology, the local field potential (LFP) has again become a popular measure of neuronal activity in both research and clinical applications. Proper understanding of the LFP requires detailed mathematical modeling incorporating the anatomical and electrophysiological features of neurons near the recording electrode, as well as synaptic inputs from the entire network. Here we propose a hybrid modeling scheme combining efficient point-neuron network models with biophysical principles underlying LFP generation by real neurons. The LFP predictions rely on populations of network-equivalent multicompartment neuron models with layer-specific synaptic connectivity, can be used with an arbitrary number of point-neuron network populations, and allows for a full separation of simulated network dynamics and LFPs. We apply the scheme to a full-scale cortical network model for a ∼1 mm 2 patch of primary visual cortex, predict laminar LFPs for different network states, assess the relative LFP contribution from different laminar populations, and investigate effects of input correlations and neuron density on the LFP. The generic nature of the hybrid scheme and its public implementation in hybridLFPy form the basis for LFP predictions from other and larger point-neuron network models, as well as extensions of the current application with additional biological detail. © The Author 2016. Published by Oxford University Press.

Effect of alloying on screw dislocation structure in Mo: atomistic modelling approach with ab-initio parametrization

NASA Astrophysics Data System (ADS)

Gornostyrev, Yu. N.

2005-03-01

The plastic deformation in bcc metals is realized by the motion of screw dislocations with a complex star-like non-planar core. In this case, the direct investigation of the solute effect by first principles electronic structure calculations is a challenging problem for which we follow a combined approach that includes atomistic dislocation modelling with ab-initio parametrization of interatomic interactions. The screw dislocation core structure in Mo alloys is described within the model of atomic row displacements along a dislocation line with the interatomic row potential estimated from total energy full-potential linear muffin-tin orbital (FLMTO) calculations with the generalized gradient approximation (GGA) for the exchange-correlation potential. We demonstrate (1) that the solute effect on the dislocation structure is different for ``hard'' and ``easy'' cores and (2) that the softener addition in a ``hard'' core gives rise to a structural transformation into a configuration with a lower energy through an intermediate state. The softener solute is shown to disturb locally the three-fold symmetry of the dislocation core and the dislocation structure tends to the split planar core.

A new generation of effective core potentials for correlated calculations

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

Bennett, Michael Chandler; Melton, Cody A.; Annaberdiyev, Abdulgani

Here, we outline ideas on desired properties for a new generation of effective core potentials (ECPs) that will allow valence-only calculations to reach the full potential offered by recent advances in many-body wave function methods. The key improvements include consistent use of correlated methods throughout ECP constructions and improved transferability as required for an accurate description of molecular systems over a range of geometries. The guiding principle is the isospectrality of all-electron and ECP Hamiltonians for a subset of valence states. We illustrate these concepts on a few first- and second-row atoms (B, C, N, O, S), and we obtainmore » higher accuracy in transferability than previous constructions while using semi-local ECPs with a small number of parameters. In addition, the constructed ECPs enable many-body calculations of valence properties with higher (or same) accuracy than their all-electron counterparts with uncorrelated cores. This implies that the ECPs include also some of the impacts of core-core and core-valence correlations on valence properties. The results open further prospects for ECP improvements and refinements.« less

A new generation of effective core potentials for correlated calculations

DOE PAGES

Bennett, Michael Chandler; Melton, Cody A.; Annaberdiyev, Abdulgani; ...

2017-12-12

Here, we outline ideas on desired properties for a new generation of effective core potentials (ECPs) that will allow valence-only calculations to reach the full potential offered by recent advances in many-body wave function methods. The key improvements include consistent use of correlated methods throughout ECP constructions and improved transferability as required for an accurate description of molecular systems over a range of geometries. The guiding principle is the isospectrality of all-electron and ECP Hamiltonians for a subset of valence states. We illustrate these concepts on a few first- and second-row atoms (B, C, N, O, S), and we obtainmore » higher accuracy in transferability than previous constructions while using semi-local ECPs with a small number of parameters. In addition, the constructed ECPs enable many-body calculations of valence properties with higher (or same) accuracy than their all-electron counterparts with uncorrelated cores. This implies that the ECPs include also some of the impacts of core-core and core-valence correlations on valence properties. The results open further prospects for ECP improvements and refinements.« less

Approaches to Foster Transfer of Formal Principles: Which Route to Take?

PubMed

Schalk, Lennart; Saalbach, Henrik; Stern, Elsbeth

2016-01-01

Enabling learners to transfer knowledge about formal principles to new problems is a major aim of science and mathematics education, which, however, is notoriously difficult to reach. Previous research advocates different approaches of how to introduce principles to foster the transfer of knowledge about formal principles. One approach suggests teaching a generic formalism of the principles. Another approach suggests presenting (at least) two concrete cases instantiating the principle. A third approach suggests presenting a generic formalism accompanied by a case. As yet, though, empirical results regarding the transfer potential of these approaches are mixed and difficult to integrate as the three approaches have rarely been tested competitively. Furthermore, the approaches have been evaluated in relation to different control conditions, and they have been assessed using varying transfer measures. In the present experiment, we introduced undergraduates to the formal principles of propositional logic with the aim to systematically compare the transfer potential of the different approaches in relation to each other and to a common control condition by using various learning and transfer tasks. Results indicate that all approaches supported successful learning and transfer of the principles, but also caused systematic differences in the magnitude of transfer. Results indicate that the combination of a generic formalism with a case was surprisingly unsuccessful while learners who compared two cases outperformed the control condition. We discuss how the simultaneous assessment of the different approaches allows to more precisely capture the underlying learning mechanisms and to advance theory on how these mechanisms contribute to transfer performance.

Optical element for full spectral purity from IR-generated EUV light sources

NASA Astrophysics Data System (ADS)

van den Boogaard, A. J. R.; Louis, E.; van Goor, F. A.; Bijkerk, F.

2009-03-01

Laser produced plasma (LLP) sources are generally considered attractive for high power EUV production in next generation lithography equipment. Such plasmas are most efficiently excited by the relatively long, infrared wavelengths of CO2-lasers, but a significant part of the rotational-vibrational excitation lines of the CO2 radiation will be backscattered by the plasma's critical density surface and consequently will be present as parasitic radiation in the spectrum of such sources. Since most optical elements in the EUV collecting and imaging train have a high reflection coefficient for IR radiation, undesirable heating phenomena at the resist level are likely to occur. In this study a completely new principle is employed to obtain full separation of EUV and IR radiation from the source by a single optical component. While the application of a transmission filter would come at the expense of EUV throughput, this technique potentially enables wavelength separation without loosing reflectance compared to a conventional Mo/Si multilayer coated element. As a result this method provides full spectral purity from the source without loss in EUV throughput. Detailed calculations on the principal of functioning are presented.

Introductory review on `Flying Triangulation': a motion-robust optical 3D measurement principle

NASA Astrophysics Data System (ADS)

Ettl, Svenja

2015-04-01

'Flying Triangulation' (FlyTri) is a recently developed principle which allows for a motion-robust optical 3D measurement of rough surfaces. It combines a simple sensor with sophisticated algorithms: a single-shot sensor acquires 2D camera images. From each camera image, a 3D profile is generated. The series of 3D profiles generated are aligned to one another by algorithms, without relying on any external tracking device. It delivers real-time feedback of the measurement process which enables an all-around measurement of objects. The principle has great potential for small-space acquisition environments, such as the measurement of the interior of a car, and motion-sensitive measurement tasks, such as the intraoral measurement of teeth. This article gives an overview of the basic ideas and applications of FlyTri. The main challenges and their solutions are discussed. Measurement examples are also given to demonstrate the potential of the measurement principle.

Uranium phase diagram from first principles

NASA Astrophysics Data System (ADS)

Yanilkin, Alexey; Kruglov, Ivan; Migdal, Kirill; Oganov, Artem; Pokatashkin, Pavel; Sergeev, Oleg

2017-06-01

The work is devoted to the investigation of uranium phase diagram up to pressure of 1 TPa and temperature of 15 kK based on density functional theory. First of all the comparison of pseudopotential and full potential calculations is carried out for different uranium phases. In the second step, phase diagram at zero temperature is investigated by means of program USPEX and pseudopotential calculations. Stable and metastable structures with close energies are selected. In order to obtain phase diagram at finite temperatures the preliminary selection of stable phases is made by free energy calculation based on small displacement method. For remaining candidates the accurate values of free energy are obtained by means of thermodynamic integration method (TIM). For this purpose quantum molecular dynamics are carried out at different volumes and temperatures. Interatomic potentials based machine learning are developed in order to consider large systems and long times for TIM. The potentials reproduce the free energy with the accuracy 1-5 meV/atom, which is sufficient for prediction of phase transitions. The equilibrium curves of different phases are obtained based on free energies. Melting curve is calculated by modified Z-method with developed potential.

A case study in the use of community-based participatory research in public health nursing.

PubMed

Savage, Christine L; Xu, Yin; Lee, Rebecca; Rose, Barbara L; Kappesser, Mary; Anthony, Jean Spann

2006-01-01

There is growing demand for research using a community-based participatory (CBPR) approach. CBPR requires that the academic research team actively partner with community members and stakeholders in the entire research process. The community members are full partners with the researchers in relation to the development and implementation of the study, analysis of the data, and dissemination of the findings. The purpose of this article is to review four basic principles of CBPR and provide an example of how these CBPR principles were used in an ethnographic study related to the culture of African American infant health. In the pilot study, CBPR provided the framework for recruitment and retention of participants, ongoing data analysis, and dissemination of findings. Using CBPR provided the researchers an introduction into the selected community. Community members served as key informants about the culture of the community and provided access to potential participants. The community partners contributed to analysis of emerging themes and in the dissemination of findings to the community, stakeholders, and the scientific community. CBPR provides opportunities for community health nurse researchers to conduct research with vulnerable populations and sets the stage for implementing evidenced-based nursing interventions in the community.

An overview of concussion in sport.

PubMed

Khurana, Vini G; Kaye, Andrew H

2012-01-01

Concussion is a sudden-onset, transient alteration of consciousness due to a combination of functional and structural brain disturbances following a physical impact transmitted to the brain. It is a common, although likely underreported, condition encountered in a wide range of sports. In the Australian Football League, concussion is estimated to occur at a rate of approximately seven injuries per team per season. While many instances of concussion are clinically mild, there is emerging evidence that a player's full recovery from a concussive injury may be more delayed and the sequelae of repeated concussions more severe than previously thought. In this light, a more conservative and rigorous approach to managing players with concussive injuries may be warranted, with the guiding principle being the player's immediate and long-term welfare. The current paper reviews the sports concussion literature. The definition, epidemiology, aetiology, pathophysiology, structural pathology, clinical features, assessment and investigation, treatment principles, and short-term and potential long-term complications of concussion are discussed. Special considerations in paediatric sports concussion, and the return-to-play implications of immediate, evolving and repetitive brain injury are also considered, as are the emerging concept and possible implications of subconcussive injury. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cross-hierarchy systems principles.

PubMed

Goentoro, Lea

2017-02-01

One driving motivation of systems biology is the search for general principles that govern the design of biological systems. But questions often arise as to what kind of general principles biology could have. Concepts from engineering such as robustness and modularity are indeed becoming a regular way of describing biological systems. Another source of potential general principles is the emerging similarities found in processes across biological hierarchies. In this piece, I describe several emerging cross-hierarchy similarities. Identification of more cross-hierarchy principles, and understanding the implications these convergence have on the construction of biological systems, I believe, present exciting challenges for systems biology in the decades to come.

Enhancing the Therapy Experience Using Principles of Video Game Design.

PubMed

Folkins, John Wm; Brackenbury, Tim; Krause, Miriam; Haviland, Allison

2016-02-01

This article considers the potential benefits that applying design principles from contemporary video games may have on enhancing therapy experiences. Six principles of video game design are presented, and their relevance for enriching clinical experiences is discussed. The motivational and learning benefits of each design principle have been discussed in the education literature as having positive impacts on student motivation and learning and are related here to aspects of clinical practice. The essential experience principle suggests connecting all aspects of the experience around a central emotion or cognitive connection. The discovery principle promotes indirect learning in focused environments. The risk-taking principle addresses the uncertainties clients face when attempting newly learned skills in novel situations. The generalization principle encourages multiple opportunities for skill transfer. The reward system principle directly relates to the scaffolding of frequent and varied feedback in treatment. Last, the identity principle can assist clients in using their newly learned communication skills to redefine self-perceptions. These principles highlight areas for research and interventions that may be used to reinforce or advance current practice.

Balancing access to participation in research and protection from risks: applying the principle of justice.

PubMed

Kiskaddon, Sarah H

2005-04-01

The problem for Institutional Review Boards (IRBs) of balancing access to participation in research with protection of research subjects has always been a difficult one. IRBs, charged with applying the "Common Rule," as well as the Belmont Principles, in their review of clinical research, are given little guidance on approaching this problem. This article argues that the third Belmont Principle, the Justice Principle, may provide a useful framework for considering this balance. The changing research environment is discussed in an historical context, and the Justice Principle is considered both in the context of individual rights, as well as the potential benefit to classes of people. The author further suggests that application of the Justice Principle be driven by findings derived from an analysis of the first 2 principles. This feedback model will enable a more formal application of the Justice Principle and less ambiguous, more transparent, decisions regarding the equitable selection of subjects. The author calls for more systematic attention to the Justice Principle by IRBs, and proposes a model that includes incorporating the deliberation of the other Belmont Principles into the Justice Principle.

Is the Pauli exclusion principle the origin of electron localisation?

NASA Astrophysics Data System (ADS)

Rincón, Luis; Torres, F. Javier; Almeida, Rafael

2018-03-01

In this work, we inquire into the origins of the electron localisation as obtained from the information content of the same-spin pair density, γσ, σ(r2∣r1). To this end, we consider systems of non-interacting and interacting identical Fermions contained in two simple 1D potential models: (1) an infinite potential well and (2) the Kronig-Penney periodic potential. The interparticle interaction is considered through the Hartree-Fock approximation as well as the configuration interaction expansion. Morover, the electron localisation is described through the Kullback-Leibler divergence between γσ, σ(r2∣r1) and its associated marginal probability. The results show that, as long as the adopted method properly includes the Pauli principle, the electronic localisation depends only modestly on the interparticle interaction. In view of the latter, one may conclude that the Pauli principle is the main responsible for the electron localisation.

Ab initio molecular simulations with numeric atom-centered orbitals

NASA Astrophysics Data System (ADS)

Blum, Volker; Gehrke, Ralf; Hanke, Felix; Havu, Paula; Havu, Ville; Ren, Xinguo; Reuter, Karsten; Scheffler, Matthias

2009-11-01

We describe a complete set of algorithms for ab initio molecular simulations based on numerically tabulated atom-centered orbitals (NAOs) to capture a wide range of molecular and materials properties from quantum-mechanical first principles. The full algorithmic framework described here is embodied in the Fritz Haber Institute "ab initio molecular simulations" (FHI-aims) computer program package. Its comprehensive description should be relevant to any other first-principles implementation based on NAOs. The focus here is on density-functional theory (DFT) in the local and semilocal (generalized gradient) approximations, but an extension to hybrid functionals, Hartree-Fock theory, and MP2/GW electron self-energies for total energies and excited states is possible within the same underlying algorithms. An all-electron/full-potential treatment that is both computationally efficient and accurate is achieved for periodic and cluster geometries on equal footing, including relaxation and ab initio molecular dynamics. We demonstrate the construction of transferable, hierarchical basis sets, allowing the calculation to range from qualitative tight-binding like accuracy to meV-level total energy convergence with the basis set. Since all basis functions are strictly localized, the otherwise computationally dominant grid-based operations scale as O(N) with system size N. Together with a scalar-relativistic treatment, the basis sets provide access to all elements from light to heavy. Both low-communication parallelization of all real-space grid based algorithms and a ScaLapack-based, customized handling of the linear algebra for all matrix operations are possible, guaranteeing efficient scaling (CPU time and memory) up to massively parallel computer systems with thousands of CPUs.

Deontological foundations for medical ethics?

PubMed

Gillon, R

1985-05-04

Gillon outlines the principles of the deontological, or duty-based, group of moral theories in one of a series of British Medical Journal articles on the philosophical foundations of medical ethics. He differentiates between monistic theories, such as Immanuel Kant's, which rely on a single moral principle, and pluralistic theories, such as that of W.D. Ross, which rely on several principles that potentially could conflict. He summarizes the contributions of Kant and Ross to the development of deontological thought, then concludes his essay with brief paragraphs on other deontological approaches to the resolution of conflicting moral principles.

Screening for infectious diseases of asylum seekers upon arrival: the necessity of the moral principle of reciprocity.

PubMed

Beeres, Dorien T; Cornish, Darren; Vonk, Machiel; Ravensbergen, Sofanne J; Maeckelberghe, Els L M; Boele Van Hensbroek, Pieter; Stienstra, Ymkje

2018-03-02

With a large number of forcibly displaced people seeking safety, the EU is facing a challenge in maintaining solidarity. Europe has seen millions of asylum seekers crossing European borders, the largest number of asylum seekers since the second world war. Endemic diseases and often failing health systems in their countries of origin, and arduous conditions during transit, raise questions around how to meet the health needs of this vulnerable population on arrival in terms of screening, vaccination, and access to timely and appropriate statutory health services. This paper explores the potential role of the principle of reciprocity, defined as the disposition 'to return good in proportion to the good we receive, and to make reparations for the harm we have done', as a mid-level principle in infectious disease screening policies. More than half of the European countries implemented screening programmes for newly arrived asylum seekers. Screening may serve to avoid potential infectious disease risks in the receiving countries as well as help identify health needs of asylum seekers. But screening may infringe upon basic rights of those screened, thus creating an ethical dilemma. The use of the principle of reciprocity can contribute to the identification of potential improvements for current screening programmes and emphasizes the importance of certain rights into guidelines for screening. It may create a two way moral obligation, upon asylum seekers to actively participate in the programme, and upon authorities to reciprocate the asylum seekers' participation and the benefits for the control of public health. The authors argue that the reciprocity principle leads to a stronger ethical justification of screening programmes and help achieve a balance between justifiable rights claims of the host population and the asylum seekers. The principle deserves a further and more thorough exploration of its potential use in the field of screening, migration and infectious diseases.

An analytical bond-order potential for carbon

DOE PAGES

Zhou, Xiaowang; Ward, Donald K.; Foster, Michael E.

2015-05-27

Carbon is the most widely studied material today because it exhibits special properties not seen in any other materials when in nano dimensions such as nanotube and graphene. Reduction of material defects created during synthesis has become critical to realize the full potential of carbon structures. Molecular dynamics (MD) simulations, in principle, allow defect formation mechanisms to be studied with high fidelity, and can, therefore, help guide experiments for defect reduction. Such MD simulations must satisfy a set of stringent requirements. First, they must employ an interatomic potential formalism that is transferable to a variety of carbon structures. Second, themore » potential needs to be appropriately parameterized to capture the property trends of important carbon structures, in particular, diamond, graphite, graphene, and nanotubes. The potential must predict the crystalline growth of the correct phases during direct MD simulations of synthesis to achieve a predictive simulation of defect formation. An unlimited number of structures not included in the potential parameterization are encountered, thus the literature carbon potentials are often not sufficient for growth simulations. We have developed an analytical bond order potential for carbon, and have made it available through the public MD simulation package LAMMPS. We also demonstrate that our potential reasonably captures the property trends of important carbon phases. As a result, stringent MD simulations convincingly show that our potential accounts not only for the crystalline growth of graphene, graphite, and carbon nanotubes but also for the transformation of graphite to diamond at high pressure.« less

An analytical bond-order potential for carbon.

PubMed

Zhou, X W; Ward, D K; Foster, M E

2015-09-05

Carbon is the most widely studied material today because it exhibits special properties not seen in any other materials when in nano dimensions such as nanotube and graphene. Reduction of material defects created during synthesis has become critical to realize the full potential of carbon structures. Molecular dynamics (MD) simulations, in principle, allow defect formation mechanisms to be studied with high fidelity, and can, therefore, help guide experiments for defect reduction. Such MD simulations must satisfy a set of stringent requirements. First, they must employ an interatomic potential formalism that is transferable to a variety of carbon structures. Second, the potential needs to be appropriately parameterized to capture the property trends of important carbon structures, in particular, diamond, graphite, graphene, and nanotubes. Most importantly, the potential must predict the crystalline growth of the correct phases during direct MD simulations of synthesis to achieve a predictive simulation of defect formation. Because an unlimited number of structures not included in the potential parameterization are encountered, the literature carbon potentials are often not sufficient for growth simulations. We have developed an analytical bond order potential for carbon, and have made it available through the public MD simulation package LAMMPS. We demonstrate that our potential reasonably captures the property trends of important carbon phases. Stringent MD simulations convincingly show that our potential accounts not only for the crystalline growth of graphene, graphite, and carbon nanotubes but also for the transformation of graphite to diamond at high pressure. © 2015 Wiley Periodicals, Inc.

Coarse-Grained Models for Automated Fragmentation and Parametrization of Molecular Databases.

PubMed

Fraaije, Johannes G E M; van Male, Jan; Becherer, Paul; Serral Gracià, Rubèn

2016-12-27

We calibrate coarse-grained interaction potentials suitable for screening large data sets in top-down fashion. Three new algorithms are introduced: (i) automated decomposition of molecules into coarse-grained units (fragmentation); (ii) Coarse-Grained Reference Interaction Site Model-Hypernetted Chain (CG RISM-HNC) as an intermediate proxy for dissipative particle dynamics (DPD); and (iii) a simple top-down coarse-grained interaction potential/model based on activity coefficient theories from engineering (using COSMO-RS). We find that the fragment distribution follows Zipf and Heaps scaling laws. The accuracy in Gibbs energy of mixing calculations is a few tenths of a kilocalorie per mole. As a final proof of principle, we use full coarse-grained sampling through DPD thermodynamics integration to calculate log P OW for 4627 compounds with an average error of 0.84 log unit. The computational speeds per calculation are a few seconds for CG RISM-HNC and a few minutes for DPD thermodynamic integration.

Enhancing and targeting nucleic acid delivery by magnetic force.

PubMed

Plank, Christian; Anton, Martina; Rudolph, Carsten; Rosenecker, Joseph; Krötz, Florian

2003-08-01

Insufficient contact of inherently highly active nucleic acid delivery systems with target cells is a primary reason for their often observed limited efficacy. Physical methods of targeting can overcome this limitation and reduce the risk of undesired side effects due to non-target site delivery. The authors and others have developed a novel means of physical targeting, exploiting magnetic force acting on nucleic acid vectors associated with magnetic particles in order to mediate the rapid contact of vectors with target cells. Here, the principles of magnetic drug and nucleic acid delivery are reviewed, and the facts and potentials of the technique for research and therapeutic applications are discussed. Magnetically enhanced nucleic acid delivery - magnetofection - is universally applicable to viral and non-viral vectors, is extraordinarily rapid, simple and yields saturation level transfection at low dose in vitro. The method is useful for site-specific vector targeting in vivo. Exploiting the full potential of the technique requires an interdisciplinary research effort in magnetic field physics, magnetic particle chemistry, pharmaceutical formulation and medical application.

Electric-field-induced modification in Dzyaloshinskii-Moriya interaction of Co monolayer on Pt(111)

NASA Astrophysics Data System (ADS)

Nakamura, Kohji; Akiyama, Toru; Ito, Tomonori; Ono, Teruo; Weinert, Michael

Magnetism induced by an external electric field (E-field) has received much attention as a potential approach for controlling magnetism at the nano-scale with the promise of ultra-low energy power consumption. Here, the E-field-induced modification of the Dzyaloshinskii-Moriya interaction (DMI) for a prototypical transition-metal thin layer of a Co monolayer on Pt(111) is investigated by first-principles calculations by using the full-potential linearized augmented plane wave method that treats spin-spiral structures in an E-field. With inclusion of the spin-orbit coupling (SOC) by the second variational method for commensurate spin-spiral structures, the DMI constants were estimated from an asymmetric contribution in the total energy with respect to the spin-spiral wavevector. The results predicted that the DMI is modified by the E-field, but the change is found to be small compared to that in the exchange interaction (a symmetric contribution in the total energy) by a factor of ten.

Electric-field-induced modification in Curie temperature of Co monolayer on Pt(111)

NASA Astrophysics Data System (ADS)

Nakamura, Kohji; Oba, Mikito; Akiyama, Toru; Ito, Tomonori; Weinert, Michael

2015-03-01

Magnetism induced by an external electric field (E-field) has received much attention as a potential approach for controlling magnetism at the nano-scale with the promise of ultra-low energy power consumption. Here, the E-field-induced modification of the Curie temperature for a prototypical transition-metal thin layer of a Co monolayer on Pt(111) is investigated by first-principles calculations by using the full-potential linearized augmented plane wave method that treats spin-spiral structures in an E-field. An applied E-field modifies the magnon (spin-spiral formation) energies by a few meV, which leads to a modification of the exchange pair interaction parameters within the classical Heisenberg model. With inclusion of the spin-orbit coupling (SOC), the magnetocrystalline anisotropy and the Dzyaloshinskii-Morita interaction are obtained by the second variation SOC method. An E-field-induced modification of the Curie temperature is demonstrated by Monte Carlo simulations, in which a change in the exchange interaction is found to play a key role.

Redox potential trend with transition metal elements in lithium-ion battery cathode materials

NASA Astrophysics Data System (ADS)

Chen, Zhenlian; Li, Jun

2013-03-01

First-principles calculations are performed to investigate the relationship between the intrinsic voltage and element-lattice for the popular transition metal oxides and polyoxyanionic compounds as cathode materials for lithium-ion batteries. A V-shape redox potential in olivine phosphates LiMPO4 and orthogonal silicates Li2MSiO4 (M =Mn, Fe, Co, Ni), and an N-shape one in layered oxides LiMO2 (M =Mn, Fe, Co, Ni, Cu) relative to transition metal M elements are found to be inversely characteristic of electronic energy contribution, which costs energy in the lithiation process and is defined as electron affinity. The maxima of electron affinity, locating at different elements for different types of crystal lattices are determined by delectronic configurations that cross the turning point of a full occupancy of electronic bands, which is determined by the cooperative effect of crystal field splitting and intraionic exchange interactions. The Ningbo Key Innovation Team, National Natural Science Foundation of China, Postdoctoral Foundation of China

Urban Environment Development based on Universal Design Principles

NASA Astrophysics Data System (ADS)

Harsritanto, Bangun Ir

2018-02-01

Universal Design is a design which facilitated full range of human diversity. By applying Universal design principles, urban environment can be more functional and more user-friendly for everyone. This study examined five urban streets of South Korea as a country experienced on developing various urban street designs based on universal design. This study aimed to examine and compare the South Korea cases using seven principles of universal design. The research methods of this study are literature study, case study, and site observation. The results of this study are: South Korea cases are good practices, urgency of implementing the direction into local regulations; and change of urban development paradigm.

[The anthropic principle in biology and radiobiology].

PubMed

Akif'ev, A P; Degtiarev, S V

1999-01-01

In accordance with the anthropic principle of the Universe the physical constants of fundamental particles of matter and the laws of their counteraction are those that an appearance of man and mind becomes possible and necessary. It is suggested to add some biological constants to the set of fundamental constants. With reparation of DNA as an example it was shown how a cell ran some parameters of Watson-Crick double helix. It was pointed that the concept of the anthropic principle of the Universe in its full body including biological constants is a key to developing of a unified theory of evolution of the Universe within the limits of scientific creationism.

10 CFR 600.313 - Cost sharing or matching.

Code of Federal Regulations, 2013 CFR

2013-01-01

... of recipient's employees. Values are established in accordance with the applicable cost principles in... use charges. The full value of the item may be applied when the item will be consumed in the performance of the award or fully depreciated by the end of the award. In cases where the full value of a...

10 CFR 600.313 - Cost sharing or matching.

Code of Federal Regulations, 2011 CFR

2011-01-01

... of recipient's employees. Values are established in accordance with the applicable cost principles in... use charges. The full value of the item may be applied when the item will be consumed in the performance of the award or fully depreciated by the end of the award. In cases where the full value of a...

10 CFR 600.313 - Cost sharing or matching.

Code of Federal Regulations, 2012 CFR

2012-01-01

... of recipient's employees. Values are established in accordance with the applicable cost principles in... use charges. The full value of the item may be applied when the item will be consumed in the performance of the award or fully depreciated by the end of the award. In cases where the full value of a...

10 CFR 600.313 - Cost sharing or matching.

Code of Federal Regulations, 2014 CFR

2014-01-01

... of recipient's employees. Values are established in accordance with the applicable cost principles in... use charges. The full value of the item may be applied when the item will be consumed in the performance of the award or fully depreciated by the end of the award. In cases where the full value of a...

Approaches to Foster Transfer of Formal Principles: Which Route to Take?

PubMed Central

Schalk, Lennart; Saalbach, Henrik; Stern, Elsbeth

2016-01-01

Enabling learners to transfer knowledge about formal principles to new problems is a major aim of science and mathematics education, which, however, is notoriously difficult to reach. Previous research advocates different approaches of how to introduce principles to foster the transfer of knowledge about formal principles. One approach suggests teaching a generic formalism of the principles. Another approach suggests presenting (at least) two concrete cases instantiating the principle. A third approach suggests presenting a generic formalism accompanied by a case. As yet, though, empirical results regarding the transfer potential of these approaches are mixed and difficult to integrate as the three approaches have rarely been tested competitively. Furthermore, the approaches have been evaluated in relation to different control conditions, and they have been assessed using varying transfer measures. In the present experiment, we introduced undergraduates to the formal principles of propositional logic with the aim to systematically compare the transfer potential of the different approaches in relation to each other and to a common control condition by using various learning and transfer tasks. Results indicate that all approaches supported successful learning and transfer of the principles, but also caused systematic differences in the magnitude of transfer. Results indicate that the combination of a generic formalism with a case was surprisingly unsuccessful while learners who compared two cases outperformed the control condition. We discuss how the simultaneous assessment of the different approaches allows to more precisely capture the underlying learning mechanisms and to advance theory on how these mechanisms contribute to transfer performance. PMID:26871902

Enhancing the effectiveness of tobacco package warning labels: a social psychological perspective

PubMed Central

Strahan, E; White, K; Fong, G; Fabrigar, L; Zanna, M; Cameron, R

2002-01-01

Objective: To outline social psychological principles that could influence the psychosocial and behavioural effects of tobacco warning labels, and to inform the development of more effective tobacco warning labels. Data sources: PsycInfo and Medline literature searches and expert guided selection of principles and theories in social psychology and of tobacco warning labels, including articles, books, and reports. Conclusions: Tobacco warning labels represent a potentially effective method of influencing attitudes and behaviours. This review describes social psychological principles that could be used to guide the creation of more effective warning labels. The potential value of incorporating warning labels into a broader public health education campaign is discussed, and directions for future research are suggested. PMID:12198266

How much of Toyota's philosophy is embedded in health care at the organisational level? A review.

PubMed

Antierens, Alain; Beeckman, Dimitri; Verhaeghe, Sofie; Myny, Dries; Van Hecke, Ann

2018-05-01

Identify which of Toyota's principles are reported in health care institutions at the organisational level and to identify the type of reported outcomes related to the effectiveness of lean production reported in these studies. No scientific research has been conducted to determine which of Toyota's principles are embedded in health care systems. This knowledge is needed to perform targeted adjustments in health care. Sixty studies were identified for the final analysis. Some Toyota Way principles appear more deeply embedded in health care institutions than others are. Not all principles of Toyota's philosophy and production system were embedded in the studies in this review. The type of reported outcomes at the organisational level was diverse. This literature review increases our knowledge about how many (and which) of the Toyota Way principles are embedded in health care. This knowledge may support reflection by nursing managers about how the full range of lean management principles could be embedded at the managerial and/or operational level. © 2018 John Wiley & Sons Ltd.

Are Key Principles for improved health technology assessment supported and used by health technology assessment organizations?

PubMed

Neumann, Peter J; Drummond, Michael F; Jönsson, Bengt; Luce, Bryan R; Schwartz, J Sanford; Siebert, Uwe; Sullivan, Sean D

2010-01-01

Previously, our group-the International Working Group for HTA Advancement-proposed a set of fifteen Key Principles that could be applied to health technology assessment (HTA) programs in different jurisdictions and across a range of organizations and perspectives. In this commentary, we investigate the extent to which these principles are supported and used by fourteen selected HTA organizations worldwide. We find that some principles are broadly supported: examples include being explicit about HTA goals and scope; considering a wide range of evidence and outcomes; and being unbiased and transparent. Other principles receive less widespread support: examples are addressing issues of generalizability and transferability; being transparent on the link between HTA findings and decision-making processes; considering a full societal perspective; and monitoring the implementation of HTA findings. The analysis also suggests a lack of consensus in the field about some principles--for example, considering a societal perspective. Our study highlights differences in the uptake of key principles for HTA and indicates considerable room for improvement for HTA organizations to adopt principles identified to reflect good HTA practices. Most HTA organizations espouse certain general concepts of good practice--for example, assessments should be unbiased and transparent. However, principles that require more intensive follow-up--for example, monitoring the implementation of HTA findings--have received little support and execution.

Ab initio joint density-functional theory of solvated electrodes, with model and explicit solvation

NASA Astrophysics Data System (ADS)

Arias, Tomas

2015-03-01

First-principles guided design of improved electrochemical systems has the potential for great societal impact by making non-fossil-fuel systems economically viable. Potential applications include improvements in fuel-cells, solar-fuel systems (``artificial photosynthesis''), supercapacitors and batteries. Economical fuel-cell systems would enable zero-carbon footprint transportation, solar-fuel systems would directly convert sunlight and water into hydrogen fuel for such fuel-cell vehicles, supercapacitors would enable nearly full recovery of energy lost during vehicle braking thus extending electric vehicle range and acceptance, and economical high-capacity batteries would be central to mitigating the indeterminacy of renewable resources such as wind and solar. Central to the operation of all of the above electrochemical systems is the electrode-electrolyte interface, whose underlying physics is quite rich, yet remains remarkably poorly understood. The essential underlying technical challenge to the first principles studies which could explore this physics is the need to properly represent simultaneously both the interaction between electron-transfer events at the electrode, which demand a quantum mechanical description, and multiscale phenomena in the liquid environment such as the electrochemical double layer (ECDL) and its associated shielding, which demand a statistical description. A direct ab initio approach to this challenge would, in principle, require statistical sampling and thousands of repetitions of already computationally demanding quantum mechanical calculations. This talk will begin with a brief review of a recent advance, joint density-functional theory (JDFT), which allows for a fully rigorous and, in principle, exact representation of the thermodynamic equilibrium between a system described at the quantum-mechanical level and a liquid environment, but without the need for costly sampling. We then shall demonstrate how this approach applies in the electrochemical context and how it is needed for realistic description of solvated electrode systems [], and how simple ``implicit'' polarized continuum methods fail radically in this context. Finally, we shall present a series of results relevant to battery, supercapacitor, and solar-fuel systems, one of which has led to a recent invention disclosure for improving battery cycle lifetimes. Supported as a part of the Energy Materials Center at Cornell, an Energy Frontier Research Center funded by DOE/BES (award de-sc0001086) and by the New York State Division of Science, Technology and Innovation (NYSTAR, award 60923).

Communicating with the public about risk

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

Wade, C R; Molony, S T; Durbin, M E

1992-01-01

Risk communication is a growing specialty field in communication that draws from well-established principles of sociology and psychology. It is a new way to communicate with potentially hostile audiences about sensitive environmental, safety, and health issues they face. This paper explains the most important principles of risk communication and discusses audience analyses, perceptions of risk (outrage factors), and risk comparisons. These principles are applied to a risk communication issue in Malhuevo, a fictitious Arizona community.

The North American model and captive cervid facilities—What is the threat?

USGS Publications Warehouse

Organ, John F.; Decker, Thomas A.; Lama, Tanya M.

2016-01-01

The North American Model of Wildlife Conservation represents the key principles that in combination resulted in a distinct form of wildlife conservation in the United States and Canada. How and to what extent captive cervid facilities comport with or conflict with these principles has implications for wildlife conservation. Greatest threats appear to be toward principles of public ownership of wildlife, allocation of wildlife by law, and in policy decisions based on science. Captive cervid facilities have potential to contribute to erosion of the underlying principles of the Model and could undermine public support for conservation initiatives.

Toward the full and proper implementation of Jordan's Principle: An elusive goal to date.

PubMed

Blackstock, Cindy

2016-01-01

First Nations children experience service delays, disruptions and denials due to jurisdictional payment disputes within and between federal and provincial/territorial governments. The House of Commons sought to ensure First Nations children could access government services on the same terms as other children when it unanimously passed a private members motion in support of Jordan's Principle in 2007. Jordan's Principle states that when a jurisdictional dispute arises regarding public services for a First Nations child that are otherwise available to other children, the government of first contact pays for the service and addresses payment disputes later. Unfortunately, the federal government adopted a definition of Jordan's Principle that was so narrow (complex medical needs with multiple service providers) that no child ever qualified. This narrow definition has been found to be unlawful by the Federal Court of Canada and the Canadian Human Rights Tribunal. The present commentary describes Jordan's Principle, the legal cases that have considered it and the implications of those decisions for health care providers.

Ab Initio Study of Electronic Structure, Elastic and Transport Properties of Fluoroperovskite LiBeF3

NASA Astrophysics Data System (ADS)

Benmhidi, H.; Rached, H.; Rached, D.; Benkabou, M.

2017-04-01

The aim of this work is to investigate the electronic, mechanical, and transport properties of the fluoroperovskite compound LiBeF3 by first-principles calculations using the full-potential linear muffin-tin orbital method based on density functional theory within the local density approximation. The independent elastic constants and related mechanical properties including the bulk modulus ( B), shear modulus ( G), Young's modulus ( E), and Poisson's ratio ( ν) have been studied, yielding the elastic moduli, shear wave velocities, and Debye temperature. According to the electronic properties, this compound is an indirect-bandgap material, in good agreement with available theoretical data. The electron effective mass, hole effective mass, and energy bandgaps with their volume and pressure dependence are investigated for the first time.

Isolation and Versatile Derivatization of an Unsaturated Anionic Silicon Cluster (Siliconoid)

PubMed Central

Willmes, Philipp; Leszczyńska, Kinga; Heider, Yannic; Abersfelder, Kai; Zimmer, Michael; Huch, Volker

2016-01-01

Abstract The characteristic features of bulk silicon surfaces are echoed in the related partially substituted—and thus unsaturated—neutral silicon clusters (siliconoids). The incorporation of siliconoids into more‐extended frameworks is promising owing to their unique electronic features, but further developments in this regard are limited by the notable absence of functionalized siliconoid derivatives until now. Herein we report the isolation and full characterization of the lithium salt of an anionic R5Si6‐siliconoid, thus providing the missing link between silicon‐based Zintl anions and siliconoid clusters. Proof‐of‐principle for the high potential of this species for the efficient transfer of the intact unsaturated R5Si6 moiety is demonstrated by clean reactions with representative electrophiles of Groups 13, 14, and 15. PMID:26800440

First-principles supercell calculations of small polarons with proper account for long-range polarization effects

NASA Astrophysics Data System (ADS)

Kokott, Sebastian; Levchenko, Sergey V.; Rinke, Patrick; Scheffler, Matthias

2018-03-01

We present a density functional theory (DFT) based supercell approach for modeling small polarons with proper account for the long-range elastic response of the material. Our analysis of the supercell dependence of the polaron properties (e.g., atomic structure, binding energy, and the polaron level) reveals long-range electrostatic effects and the electron–phonon (el–ph) interaction as the two main contributors. We develop a correction scheme for DFT polaron calculations that significantly reduces the dependence of polaron properties on the DFT exchange-correlation functional and the size of the supercell in the limit of strong el–ph coupling. Using our correction approach, we present accurate all-electron full-potential DFT results for small polarons in rocksalt MgO and rutile TiO2.

An ab initio study of the effects of vacancies on the static and dynamic magnetic properties of Co2MnSi

NASA Astrophysics Data System (ADS)

Pradines, B.; Arras, R.; Calmels, L.

2017-10-01

The full-Heusler alloy Co2MnSi is a promising highly spin-polarized magnetic metal for spintronic applications. However, significant differences have been reported between the computed properties of the ideal material and the properties of real samples measured in experiments. In this paper, we study the influence of atom vacancies on the electronic structure and on the magnetic properties of Co2MnSi, as these defects could explain the disagreement between the expected and measured behavior of this alloy. The effects of atom vacancies have been calculated from first principles, using the fully relativistic Korringa-Kohn-Rostoker (KKR) method in conjunction with the coherent potential approximation (CPA) and the linear response formalism.

An Overhead Demonstration of Some Descriptive Chemistry of the Halogens and LeChatelier's Principle.

ERIC Educational Resources Information Center

Hansen, Robert C.

1988-01-01

Describes a demonstration procedure using controlled reduction potentials to predict observed color changes which are then experimentally verified. Demonstrates the usefulness of this procedure in helping students understand LeChatelier's principle and the solubilit rule "like dissolves like." (CW)

40 CFR Appendix C to Part 50 - Measurement Principle and Calibration Procedure for the Measurement of Carbon Monoxide in the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... measurement interference from water vapor, carbon dioxide (CO2), or other species. Also, various schemes may....0Interferences 3.1The NDIR measurement principle is potentially susceptible to interference from water vapor and...

Development of a direct experimental test for any violation of the equivalence principle by the weak interaction

NASA Technical Reports Server (NTRS)

Parker, P. D. M.

1981-01-01

Violation of the equivalence principle by the weak interaction is tested. Any variation of the weak interaction coupling constant with gravitational potential, i.e., a spatial variation of the fundamental constants is investigated. The level of sensitivity required for such a measurement is estimated on the basis of the size of a change in the gravitational potential which is accessible. The alpha particle spectrum is analyzed, and the counting rate was improved by a factor of approximately 100.

Antibody-Based Sensors: Principles, Problems and Potential for Detection of Pathogens and Associated Toxins

PubMed Central

Byrne, Barry; Stack, Edwina; Gilmartin, Niamh; O'Kennedy, Richard

2009-01-01

Antibody-based sensors permit the rapid and sensitive analysis of a range of pathogens and associated toxins. A critical assessment of the implementation of such formats is provided, with reference to their principles, problems and potential for ‘on-site’ analysis. Particular emphasis is placed on the detection of foodborne bacterial pathogens, such as Escherichia coli and Listeria monocytogenes, and additional examples relating to the monitoring of fungal pathogens, viruses, mycotoxins, marine toxins and parasites are also provided. PMID:22408533

GUP parameter from quantum corrections to the Newtonian potential

NASA Astrophysics Data System (ADS)

Scardigli, Fabio; Lambiase, Gaetano; Vagenas, Elias C.

2017-04-01

We propose a technique to compute the deformation parameter of the generalized uncertainty principle by using the leading quantum corrections to the Newtonian potential. We just assume General Relativity as theory of Gravitation, and the thermal nature of the GUP corrections to the Hawking spectrum. With these minimal assumptions our calculation gives, to first order, a specific numerical result. The physical meaning of this value is discussed, and compared with the previously obtained bounds on the generalized uncertainty principle deformation parameter.

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

Nesterov, V. A., E-mail: archerix@ukpost.ua

On the basis of the energy-density method, the effect of simultaneously taking into account the Pauli exclusion principle and the monopole and quadrupole polarizations of interacting nuclei on their interaction potential is considered for the example of the {sup 16}O + {sup 16}O system by using the wave function for the two-center shell model. The calculations performed in the adiabatic approximation reveal that the inclusion of the Pauli exclusion principle and the polarization of interacting nuclei, especially their quadrupole polarization, has a substantial effect on the potential of the nucleus-nucleus interaction.

Quasi-static responses and variational principles in gradient plasticity

NASA Astrophysics Data System (ADS)

Nguyen, Quoc-Son

2016-12-01

Gradient models have been much discussed in the literature for the study of time-dependent or time-independent processes such as visco-plasticity, plasticity and damage. This paper is devoted to the theory of Standard Gradient Plasticity at small strain. A general and consistent mathematical description available for common time-independent behaviours is presented. Our attention is focussed on the derivation of general results such as the description of the governing equations for the global response and the derivation of related variational principles in terms of the energy and the dissipation potentials. It is shown that the quasi-static response under a loading path is a solution of an evolution variational inequality as in classical plasticity. The rate problem and the rate minimum principle are revisited. A time-discretization by the implicit scheme of the evolution equation leads to the increment problem. An increment of the response associated with a load increment is a solution of a variational inequality and satisfies also a minimum principle if the energy potential is convex. The increment minimum principle deals with stables solutions of the variational inequality. Some numerical methods are discussed in view of the numerical simulation of the quasi-static response.

Mechanical-Kinetic Modeling of a Molecular Walker from a Modular Design Principle

NASA Astrophysics Data System (ADS)

Hou, Ruizheng; Loh, Iong Ying; Li, Hongrong; Wang, Zhisong

2017-02-01

Artificial molecular walkers beyond burnt-bridge designs are complex nanomachines that potentially replicate biological walkers in mechanisms and functionalities. Improving the man-made walkers up to performance for widespread applications remains difficult, largely because their biomimetic design principles involve entangled kinetic and mechanical effects to complicate the link between a walker's construction and ultimate performance. Here, a synergic mechanical-kinetic model is developed for a recently reported DNA bipedal walker, which is based on a modular design principle, potentially enabling many directional walkers driven by a length-switching engine. The model reproduces the experimental data of the walker, and identifies its performance-limiting factors. The model also captures features common to the underlying design principle, including counterintuitive performance-construction relations that are explained by detailed balance, entropy production, and bias cancellation. While indicating a low directional fidelity for the present walker, the model suggests the possibility of improving the fidelity above 90% by a more powerful engine, which may be an improved version of the present engine or an entirely new engine motif, thanks to the flexible design principle. The model is readily adaptable to aid these experimental developments towards high-performance molecular walkers.

Optical recording of action potentials and other discrete physiological events: a perspective from signal detection theory.

PubMed

Sjulson, Lucas; Miesenböck, Gero

2007-02-01

Optical imaging of physiological events in real time can yield insights into biological function that would be difficult to obtain by other experimental means. However, the detection of all-or-none events, such as action potentials or vesicle fusion events, in noisy single-trial data often requires a careful balance of tradeoffs. The analysis of such experiments, as well as the design of optical reporters and instrumentation for them, is aided by an understanding of the principles of signal detection. This review illustrates these principles, using as an example action potential recording with optical voltage reporters.

The potentiality of medicinal plants as the source of new contraceptive principles in males

PubMed Central

Ogbuewu, Ifeanyi Princewill; Unamba-Oparah, Ihemdirim Chukwuma; Odoemenam, Victor Udodirim; Etuk, Idorenyin Friday; Okoli, Ifeanyi Charles

2011-01-01

Rising human population throughout the world especially in developing and underdeveloped countries has detrimental effects on life supporting system on earth. Traditionally, plants have been used to treat different kinds of ailments. The growing importance of phytochemicals in males has been reported. Contraceptive ability of plants has been reported in several animal models. The reversibility of the anti-fertility effects of plants and its active compounds are of potential clinical relevance in the development of male contraceptive. This review attempts to discuss the latest reports on the potentiality of medicinal plants as the source of new contraceptive principles in males. PMID:22540095

NO{sub x}-abatement potential of lean-premixed GT combustors

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

Sattelmayer, T.; Polifke, W.; Winkler, D.

1998-01-01

The influence of the structure of perfectly premixed flames on NO{sub x} formation is investigated theoretically. Since a network of reaction kinetics modules and model flames is used for this purpose, the results obtained are independent of specific burner geometries. Calculations are presented for a mixture temperature of 630 K, an adiabatic flame temperature of 1840 K, and 1 and 15 bars combustor pressure. In particular, the following effects are studied separately from each other: molecular diffusion of temperature and species, flame strain, local quench in highly strained flames and subsequent reignition, turbulent diffusion (no preferential diffusion), and small scalemore » mixing (stirring) in the flame front. Either no relevant influence or an increase in NO{sub x} burners is to avoid excessive turbulent stirring in the flame front. Turbulent flames that exhibit locally and instantaneously near laminar structures (flamelets) appear to be optimal. Using the same methodology, the scope of the investigation is extended to lean-lean staging, since a higher NO{sub x}-abatement potential can be expected in principle. As long as the chemical reactions of the second stage take place in the boundary between the fresh mixture of the second stage and the combustion products from upstream, no advantage can be expected from lean-lean staging. Only if the preliminary burner exhibits much poorer mixing than the second stage can lean-lean staging be beneficial. In contrast, if full mixing between the two stages prior to afterburning can be achieved (lean-mix-lean technique), the combustor outlet temperature can in principle be increased somewhat without NO penalty.« less

A Neuroscience Perspective on Learning

ERIC Educational Resources Information Center

Sloan, Dendy; Norrgran, Cynthia

2016-01-01

We briefly discuss memory types and three modern principles of neuroscience: 1) Protein growth at the synapse, 2) the three-brain theory, and 3) the interplay of the hippocampus, the neocortex, and the prefrontal cortex. To illustrate the potential of this perspective, four applications of these principles are provided.

Effective intermolecular potential and critical point for C60 molecule

NASA Astrophysics Data System (ADS)

Ramos, J. Eloy

2017-07-01

The approximate nonconformal (ANC) theory is applied to the C60 molecule. A new binary potential function is developed for C60, which has three parameters only and is obtained by averaging the site-site carbon interactions on the surface of two C60 molecules. It is shown that the C60 molecule follows, to a good approximation, the corresponding states principle with n-C8H18, n-C4F10 and n-C5F12. The critical point of C60 is estimated in two ways: first by applying the corresponding states principle under the framework of the ANC theory, and then by using previous computer simulations. The critical parameters obtained by applying the corresponding states principle, although very different from those reported in the literature, are consistent with the previous results of the ANC theory. It is shown that the Girifalco potential does not correspond to an average of the site-site carbon-carbon interaction.

Differential Ion Mobility Separations in up to 100 % Helium Using Microchips

PubMed Central

Shvartsburg, Alexandre A.; Ibrahim, Yehia M.; Smith, Richard D.

2014-01-01

The performance of differential IMS (FAIMS) analyzers is much enhanced by gases comprising He, especially He/N2 mixtures. However, electrical breakdown has limited the He fraction to ~50 %–75 %, depending on the field strength. By the Paschen law, the threshold field for breakdown increases at shorter distances. This allows FAIMS using chips with microscopic channels to utilize much stronger field intensities (E) than “full-size” analyzers with wider gaps. Here we show that those chips can employ higher He fractions up to 100 %. Use of He-rich gases improves the resolution and resolution/sensitivity balance substantially, although less than for full-size analyzers. The optimum He fraction is ~80 %, in line with first-principles theory. Hence, one can now measure the dependences of ion mobility on E in pure He, where ion-molecule cross section calculations are much more tractable than in other gases that form deeper and more complex interaction potentials. This capability may facilitate quantitative modeling of high-field ion mobility behavior and, thus, FAIMS separation properties, which would enable a priori extraction of structural information about the ions. PMID:24402673

Commentary: Coming Full Circle--Psychoanalysis, Psychodynamics, and Forensic Psychiatry.

PubMed

Hegarty, Angela M

2015-12-01

Drs. Simopoulos and Cohen argue that knowledge of one's unconscious processes improves the forensic psychiatrist's capacity to manage complex forensic situations and to generate forensic formulations and opinions that are demonstrably more valid and reliable, much like competence in cultural assessment and formulation. In practice, the challenges posed by the application of these principles in forensic settings are far outweighed by the potential benefit. Forensic practice is informed by many specialties. Forensic psychiatrists do not have to complete full training in these disciplines to make use of the knowledge and perspectives they offer. The same may not be true of psychodynamic assessment and formulation. Although much can be learned from supervision, case seminars, conferences, and reading, such knowledge does little to foster awareness of one's unconscious processes that by definition operate outside awareness and thus contribute to the vitiating effect of bias. To date, the only method whereby psychiatrists can effectively come to appreciate their own unconscious processes in action is arguably through their own analysis conducted in the course of training in analysis or psychodynamic psychotherapy. © 2015 American Academy of Psychiatry and the Law.

Full-color large-scaled computer-generated holograms using RGB color filters.

PubMed

Tsuchiyama, Yasuhiro; Matsushima, Kyoji

2017-02-06

A technique using RGB color filters is proposed for creating high-quality full-color computer-generated holograms (CGHs). The fringe of these CGHs is composed of more than a billion pixels. The CGHs reconstruct full-parallax three-dimensional color images with a deep sensation of depth caused by natural motion parallax. The simulation technique as well as the principle and challenges of high-quality full-color reconstruction are presented to address the design of filter properties suitable for large-scaled CGHs. Optical reconstructions of actual fabricated full-color CGHs are demonstrated in order to verify the proposed techniques.

Lunar exploration rover program developments

NASA Technical Reports Server (NTRS)

Klarer, P. R.

1994-01-01

The Robotic All Terrain Lunar Exploration Rover (RATLER) design concept began at Sandia National Laboratories in late 1991 with a series of small, proof-of-principle, working scale models. The models proved the viability of the concept for high mobility through mechanical simplicity, and eventually received internal funding at Sandia National Laboratories for full scale, proof-of-concept prototype development. Whereas the proof-of-principle models demonstrated the mechanical design's capabilities for mobility, the full scale proof-of-concept design currently under development is intended to support field operations for experiments in telerobotics, autonomous robotic operations, telerobotic field geology, and advanced man-machine interface concepts. The development program's current status is described, including an outline of the program's work over the past year, recent accomplishments, and plans for follow-on development work.

Redox condition in molten salts and solute behavior: A first-principles molecular dynamics study

NASA Astrophysics Data System (ADS)

Nam, Hyo On; Morgan, Dane

2015-10-01

Molten salts technology is of significant interest for nuclear, solar, and other energy systems. In this work, first-principles molecular dynamics (FPMD) was used to model the solute behavior in eutectic LiCl-KCl and FLiBe (Li2BeF4) melts at 773 K and 973 K, respectively. The thermo-kinetic properties for solute systems such as the redox potential, solute diffusion coefficients and structural information surrounding the solute were predicted from FPMD modeling and the calculated properties are generally in agreement with the experiments. In particular, we formulate an approach to model redox energetics vs. chlorine (or fluorine) potential from first-principles approaches. This study develops approaches for, and demonstrates the capabilities of, FPMD to model solute properties in molten salts.

A Jeziorski-Monkhorst fully uncontracted multi-reference perturbative treatment. I. Principles, second-order versions, and tests on ground state potential energy curves

NASA Astrophysics Data System (ADS)

Giner, Emmanuel; Angeli, Celestino; Garniron, Yann; Scemama, Anthony; Malrieu, Jean-Paul

2017-06-01

The present paper introduces a new multi-reference perturbation approach developed at second order, based on a Jeziorski-Mokhorst expansion using individual Slater determinants as perturbers. Thanks to this choice of perturbers, an effective Hamiltonian may be built, allowing for the dressing of the Hamiltonian matrix within the reference space, assumed here to be a CAS-CI. Such a formulation accounts then for the coupling between the static and dynamic correlation effects. With our new definition of zeroth-order energies, these two approaches are strictly size-extensive provided that local orbitals are used, as numerically illustrated here and formally demonstrated in the Appendix. Also, the present formalism allows for the factorization of all double excitation operators, just as in internally contracted approaches, strongly reducing the computational cost of these two approaches with respect to other determinant-based perturbation theories. The accuracy of these methods has been investigated on ground-state potential curves up to full dissociation limits for a set of six molecules involving single, double, and triple bond breaking together with an excited state calculation. The spectroscopic constants obtained with the present methods are found to be in very good agreement with the full configuration interaction results. As the present formalism does not use any parameter or numerically unstable operation, the curves obtained with the two methods are smooth all along the dissociation path.

Effectiveness of alcohol prevention interventions based on the principles of social marketing: a systematic review.

PubMed

Janssen, Meriam M; Mathijssen, Jolanda J P; van Bon-Martens, Marja J H; van Oers, Hans A M; Garretsen, Henk F L

2013-06-01

Alcohol education aims to increase knowledge on the harm related to alcohol, and to change attitudes and drinking behaviour. However, little (lasting) evidence has been found for alcohol education, in changing alcohol-related attitudes and behaviour. Social marketing uses marketing techniques to achieve a social or healthy goal, and can be used in alcohol education. Social marketing consists of eight principles: customer orientation, insight, segmentation, behavioural goals, exchange, competition, methods mix, and is theory based. This review investigates the application of social marketing in alcohol prevention interventions, and whether application of social marketing influences alcohol-related attitudes or behaviour. A literature search was conducted in PubMed, PsychInfo, Cochrane and Scopus. Inclusion criteria were that original papers had to describe the effects of an alcohol prevention intervention developed according to one or more principles of social marketing. No limits were set on the age of the participants or on the kind of alcohol prevention intervention. The abstracts of the 274 retrieved studies were reviewed and the full texts of potentially relevant studies were screened. Six studies met the inclusion criteria and were included in this review. These six studies showed associations for the application of social marketing techniques on alcohol-related attitudes or behaviour; one study relates to participation in a drinking event, four to alcohol drinking behaviour, two to driving a car while under the influence of alcohol, two to recognition of campaign messages or campaign logo, and one to awareness of the campaign. However, no associations were also found. In addition, the studies had several limitations related to a control group, response rate and study methodology. Based on this review, the effect of applying the principles of social marketing in alcohol prevention in changing alcohol-related attitudes or behaviour could not be assessed. More research, with a good quality methodology, like using a randomized control trial and measuring short, medium, and long-term effects, is required on this topic. Policy implications are discussed.

Design Principles of Next-Generation Digital Gaming for Education.

ERIC Educational Resources Information Center

Squire, Kurt; Jenkins, Henry; Holland, Walter; Miller, Heather; O'Driscoll, Alice; Tan, Katie Philip; Todd, Katie.

2003-01-01

Discusses the rapid growth of digital games, describes research at MIT that is exploring the potential of digital games for supporting learning, and offers hypotheses about the design of next-generation educational video and computer games. Highlights include simulations and games; and design principles, including context and using information to…

Reconceptualizing Homework as Out-of-School Learning Opportunities. Occasional Paper 135.

ERIC Educational Resources Information Center

Alleman, Janet; Brophy, Jere

This occasional paper views homework as an opportunity to exploit the potential of outside resources and environments to complement in-school learning opportunities. Out-of-school learning opportunities are considered in the context of principles for planning and implementing learning activities. These principles involve: (1) goal relevance,…

Bridging Levels of Analysis: Learning, Information Theory, and the Lexicon

ERIC Educational Resources Information Center

Dye, Melody

2017-01-01

While information theory is typically considered in the context of modern computing and engineering, its core mathematical principles provide a potentially useful lens through which to consider human language. Like the artificial communication systems such principles were invented to describe, natural languages involve a sender and receiver, a…

Full-scale computation for all the thermoelectric property parameters of half-Heusler compounds

DOE PAGES

Hong, A. J.; Li, L.; He, R.; ...

2016-03-07

The thermoelectric performance of materials relies substantially on the band structures that determine the electronic and phononic transports, while the transport behaviors compete and counter-act for the power factor PF and figure-of-merit ZT. These issues make a full-scale computation of the whole set of thermoelectric parameters particularly attractive, while a calculation scheme of the electronic and phononic contributions to thermal conductivity remains yet challenging. In this work, we present a full-scale computation scheme based on the first-principles calculations by choosing a set of doped half- Heusler compounds as examples for illustration. The electronic structure is computed using the WIEN2k codemore » and the carrier relaxation times for electrons and holes are calculated using the Bardeen and Shockley’s deformation potential (DP) theory. The finite-temperature electronic transport is evaluated within the framework of Boltzmann transport theory. In sequence, the density functional perturbation combined with the quasi-harmonic approximation and the Klemens’ equation is implemented for calculating the lattice thermal conductivity of carrier-doped thermoelectric materials such as Tidoped NbFeSb compounds without losing a generality. The calculated results show good agreement with experimental data. Lastly, the present methodology represents an effective and powerful approach to calculate the whole set of thermoelectric properties for thermoelectric materials.« less

Revealing the global map of protein folding space by large-scale simulations

NASA Astrophysics Data System (ADS)

Sinner, Claude; Lutz, Benjamin; Verma, Abhinav; Schug, Alexander

2015-12-01

The full characterization of protein folding is a remarkable long-standing challenge both for experiment and simulation. Working towards a complete understanding of this process, one needs to cover the full diversity of existing folds and identify the general principles driving the process. Here, we want to understand and quantify the diversity in folding routes for a large and representative set of protein topologies covering the full range from all alpha helical topologies towards beta barrels guided by the key question: Does the majority of the observed routes contribute to the folding process or only a particular route? We identified a set of two-state folders among non-homologous proteins with a sequence length of 40-120 residues. For each of these proteins, we ran native-structure based simulations both with homogeneous and heterogeneous contact potentials. For each protein, we simulated dozens of folding transitions in continuous uninterrupted simulations and constructed a large database of kinetic parameters. We investigate folding routes by tracking the formation of tertiary structure interfaces and discuss whether a single specific route exists for a topology or if all routes are equiprobable. These results permit us to characterize the complete folding space for small proteins in terms of folding barrier ΔG‡, number of routes, and the route specificity RT.

Full-scale computation for all the thermoelectric property parameters of half-Heusler compounds

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

Hong, A. J.; Li, L.; He, R.

The thermoelectric performance of materials relies substantially on the band structures that determine the electronic and phononic transports, while the transport behaviors compete and counter-act for the power factor PF and figure-of-merit ZT. These issues make a full-scale computation of the whole set of thermoelectric parameters particularly attractive, while a calculation scheme of the electronic and phononic contributions to thermal conductivity remains yet challenging. In this work, we present a full-scale computation scheme based on the first-principles calculations by choosing a set of doped half- Heusler compounds as examples for illustration. The electronic structure is computed using the WIEN2k codemore » and the carrier relaxation times for electrons and holes are calculated using the Bardeen and Shockley’s deformation potential (DP) theory. The finite-temperature electronic transport is evaluated within the framework of Boltzmann transport theory. In sequence, the density functional perturbation combined with the quasi-harmonic approximation and the Klemens’ equation is implemented for calculating the lattice thermal conductivity of carrier-doped thermoelectric materials such as Tidoped NbFeSb compounds without losing a generality. The calculated results show good agreement with experimental data. Lastly, the present methodology represents an effective and powerful approach to calculate the whole set of thermoelectric properties for thermoelectric materials.« less

First full dynamic range calibration of the JUNGFRAU photon detector

NASA Astrophysics Data System (ADS)

Redford, S.; Andrä, M.; Barten, R.; Bergamaschi, A.; Brückner, M.; Dinapoli, R.; Fröjdh, E.; Greiffenberg, D.; Lopez-Cuenca, C.; Mezza, D.; Mozzanica, A.; Ramilli, M.; Ruat, M.; Ruder, C.; Schmitt, B.; Shi, X.; Thattil, D.; Tinti, G.; Vetter, S.; Zhang, J.

2018-01-01

The JUNGFRAU detector is a charge integrating hybrid silicon pixel detector developed at the Paul Scherrer Institut for photon science applications, in particular for the upcoming free electron laser SwissFEL. With a high dynamic range, analogue readout, low noise and three automatically switching gains, JUNGFRAU promises excellent performance not only at XFELs but also at synchrotrons in areas such as protein crystallography, ptychography, pump-probe and time resolved measurements. To achieve its full potential, the detector must be calibrated on a pixel-by-pixel basis. This contribution presents the current status of the JUNGFRAU calibration project, in which a variety of input charge sources are used to parametrise the energy response of the detector across four orders of magnitude of dynamic range. Building on preliminary studies, the first full calibration procedure of a JUNGFRAU 0.5 Mpixel module is described. The calibration is validated using alternative sources of charge deposition, including laboratory experiments and measurements at ESRF and LCLS. The findings from these measurements are presented. Calibrated modules have already been used in proof-of-principle style protein crystallography experiments at the SLS. A first look at selected results is shown. Aspects such as the conversion of charge to number of photons, treatment of multi-size pixels and the origin of non-linear response are also discussed.

Electronic, Optical and Thermoelectric Properties of 2H-CuAlO2: A First Principles Study

NASA Astrophysics Data System (ADS)

Bhamu, K. C.; Khenata, R.; Khan, Saleem Ayaz; Singh, Mangej; Priolkar, K. R.

2016-01-01

The electronic and optical properties of 2H-CuAlO2, including energy bands, density of states (DOS), optical dielectric behaviour, refractive index, absorption coefficient and optical conductivity, have been investigated within the framework of a full-potential linearized augmented plane wave scheme using different potentials. The direct and indirect band gaps for CuAlO2, computed using the Becke-Johnson potential, are estimated at 3.53 eV and 2.48 eV, respectively, which are in better agreement with the experimentally reported band gaps than those previously computed. The origin of energy bands is elucidated in terms of DOS, while the behaviour of the imaginary part of the dielectric constant is explained in terms of electronic transitions from valence bands to conduction bands. The computed value of the refractive index is 2.25 (1.94) for light perpendicular (parallel) to the c axis, in concordance with the available values. The overall shape of the spectral distribution for absorption coefficient and optical conductivity is also in accord with the reported data. The investigated thermoelectric properties indicate that CuAlO2 is a p-type semiconductor showing high effectiveness at low temperatures.

Comparing the Life Cycle Energy Consumption, Global ...

EPA Pesticide Factsheets

Managing the water-energy-nutrient nexus for the built environment requires, in part, a full system analysis of energy consumption, global warming and eutrophication potentials of municipal water services. As an example, we evaluated the life cycle energy use, greenhouse gas (GHG) emissions and aqueous nutrient releases of the whole anthropogenic municipal water cycle starting from raw water extraction to wastewater treatment and reuse/discharge for five municipal water and wastewater systems. The assessed options included conventional centralized services and four alternative options following the principles of source-separation and water fit-for-purpose. The comparative life cycle assessment identified that centralized drinking water supply coupled with blackwater energy recovery and on-site greywater treatment and reuse was the most energyand carbon-efficient water service system evaluated, while the conventional (drinking water and sewerage) centralized system ranked as the most energy- and carbon-intensive system. The electricity generated from blackwater and food residuals co-digestion was estimated to offset at least 40% of life cycle energy consumption for water/waste services. The dry composting toilet option demonstrated the lowest life cycle eutrophication potential. The nutrients in wastewater effluent are the dominating contributors for the eutrophication potential for the assessed system configurations. Among the parameters for which variability

Nursing application of Bobath principles in stroke care.

PubMed

Passarella, P M; Lewis, N

1987-04-01

The nursing approach in the care of stroke patients has a direct impact on functional outcome. Nursing application of Bobath principles in stroke care offers a nursing focus on involvement of the affected side; facilitation of normal tone, posture, and movement; and development of more normal function. A research study evaluating the functional gains of stroke patients demonstrated a significant level of functional improvement in those treated with Bobath principles over stroke patients treated with the traditional nursing approach. Practical methods for applying Bobath principles in patient care activities are described. These therapeutic methods provide nurses with the means to maximize stroke patients' potential and further influence their functional recovery.

And now, from the company that brought you the seven-eyed trout: Risk communication in action

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

Durbin, M.E.; Klein, S.H.; Molony, S.T.

1992-01-01

Risk communication is a growing specialty field in communication that draws from well-established principles of sociology and psychology. It is a way to communicate with potentially hostile audiences about sensitive environmental, safety, and health issues they face. This paper explains the most important principles of risk communication and discusses audience analyses, perceptions of risk (outrage factors), and risk comparisons. These principles are applied to a risk communication issue in a fictitious community.

Finite-temperature Gutzwiller approximation from the time-dependent variational principle

NASA Astrophysics Data System (ADS)

Lanatà, Nicola; Deng, Xiaoyu; Kotliar, Gabriel

2015-08-01

We develop an extension of the Gutzwiller approximation to finite temperatures based on the Dirac-Frenkel variational principle. Our method does not rely on any entropy inequality, and is substantially more accurate than the approaches proposed in previous works. We apply our theory to the single-band Hubbard model at different fillings, and show that our results compare quantitatively well with dynamical mean field theory in the metallic phase. We discuss potential applications of our technique within the framework of first-principle calculations.

The Sequential Self-Selection Auction Mechanism for Selective Reenlistment Bonuses: Potential Cost Savings to the U.S. Marine Corps

DTIC Science & Technology

2007-06-01

information than another party, such as in the market for used cars. Mankiw , in his book, “The Principles of Economics ,” defines adverse selection as...Options,” Power Point presentation e-mailed to the author, 18 May 2007, 1-9. 37 Ibid., 2. 38 Gregory N. Mankiw , Principles of Economics , Third...the Internet.” The American Economic Review. December 1999. 89 No. 5. 1066- 1078. Mankiw , Gregory N. Principles of Economics , Third Edition (Mason

Derivation of Hamilton's equations of motion for mechanical systems with constraints on the basis of Pontriagin's maximum principle

NASA Astrophysics Data System (ADS)

Kovalev, A. M.

The problem of the motion of a mechanical system with constraints conforming to Hamilton's principle is stated as an optimum control problem, with equations of motion obtained on the basis of Pontriagin's principle. A Hamiltonian function in Rodrigues-Hamilton parameters for a gyrostat in a potential force field is obtained as an example. Equations describing the motion of a skate on a sloping surface and the motion of a disk on a horizontal plane are examined.

Joint principles: Integrating behavioral health care into the patient-centered medical home.

PubMed

2014-06-01

The Patient-centered Medical Home (PCMH) is an innovative, improved, and evolving approach to providing primary care that has gained broad acceptance in the United States. The Joint Principles of the PCMH, formulated and endorsed in February 2007, are sound and describe the ideal toward which we aspire. However, there is an element running implicitly through these joint principles that is difficult to achieve yet indispensable to the success of the entire PCMH concept. The incorporation of behavioral health care has not always been included as practices transform to accommodate to the PCMH ideals. This is an alarming development because the PCMH will be incomplete and ineffective without the full incorporation of this element, and retrofitting will be much more difficult than prospectively integrating into the original design of the PCMH. Therefore we offer a complementary set of joint principles that recognizes the centrality of behavioral health care as part of the PCMH. This document follows the order and language of the original joint principles while emphasizing what needs to be addressed to insure incorporation of the essential behavioral elements. It is intended to supplement and not replace the original Joint Principles document, which still stands.

Integrated biocircuits: engineering functional multicellular circuits and devices.

PubMed

Prox, Jordan; Smith, Tory; Holl, Chad; Chehade, Nick; Guo, Liang

2018-04-01

Implantable neurotechnologies have revolutionized neuromodulatory medicine for treating the dysfunction of diseased neural circuitry. However, challenges with biocompatibility and lack of full control over neural network communication and function limits the potential to create more stable and robust neuromodulation devices. Thus, we propose a platform technology of implantable and programmable cellular systems, namely Integrated Biocircuits, which use only cells as the functional components of the device. We envision the foundational principles for this concept begins with novel in vitro platforms used for the study and reconstruction of cellular circuitry. Additionally, recent advancements in organoid and 3D culture systems account for microenvironment factors of cytoarchitecture to construct multicellular circuits as they are normally formed in the brain. We explore the current state of the art of these platforms to provide knowledge of their advancements in circuit fabrication and identify the current biological principles that could be applied in designing integrated biocircuit devices. We have highlighted the exemplary methodologies and techniques of in vitro circuit fabrication and propose the integration of selected controllable parameters, which would be required in creating suitable biodevices. We provide our perspective and propose new insights into the future of neuromodulaion devices within the scope of living cellular systems that can be applied in designing more reliable and biocompatible stimulation-based neuroprosthetics.

A framework for prescription in exercise-oncology research†

PubMed Central

Sasso, John P; Eves, Neil D; Christensen, Jesper F; Koelwyn, Graeme J; Scott, Jessica; Jones, Lee W

2015-01-01

The field of exercise-oncology has increased dramatically over the past two decades, with close to 100 published studies investigating the efficacy of structured exercise training interventions in patients with cancer. Of interest, despite considerable differences in study population and primary study end point, the vast majority of studies have tested the efficacy of an exercise prescription that adhered to traditional guidelines consisting of either supervised or home-based endurance (aerobic) training or endurance training combined with resistance training, prescribed at a moderate intensity (50–75% of a predetermined physiological parameter, typically age-predicted heart rate maximum or reserve), for two to three sessions per week, for 10 to 60 min per exercise session, for 12 to 15 weeks. The use of generic exercise prescriptions may, however, be masking the full therapeutic potential of exercise treatment in the oncology setting. Against this background, this opinion paper provides an overview of the fundamental tenets of human exercise physiology known as the principles of training, with specific application of these principles in the design and conduct of clinical trials in exercise-oncology research. We contend that the application of these guidelines will ensure continued progress in the field while optimizing the safety and efficacy of exercise treatment following a cancer diagnosis. PMID:26136187

Integrated biocircuits: engineering functional multicellular circuits and devices

NASA Astrophysics Data System (ADS)

Prox, Jordan; Smith, Tory; Holl, Chad; Chehade, Nick; Guo, Liang

2018-04-01

Objective. Implantable neurotechnologies have revolutionized neuromodulatory medicine for treating the dysfunction of diseased neural circuitry. However, challenges with biocompatibility and lack of full control over neural network communication and function limits the potential to create more stable and robust neuromodulation devices. Thus, we propose a platform technology of implantable and programmable cellular systems, namely Integrated Biocircuits, which use only cells as the functional components of the device. Approach. We envision the foundational principles for this concept begins with novel in vitro platforms used for the study and reconstruction of cellular circuitry. Additionally, recent advancements in organoid and 3D culture systems account for microenvironment factors of cytoarchitecture to construct multicellular circuits as they are normally formed in the brain. We explore the current state of the art of these platforms to provide knowledge of their advancements in circuit fabrication and identify the current biological principles that could be applied in designing integrated biocircuit devices. Main results. We have highlighted the exemplary methodologies and techniques of in vitro circuit fabrication and propose the integration of selected controllable parameters, which would be required in creating suitable biodevices. Significance. We provide our perspective and propose new insights into the future of neuromodulaion devices within the scope of living cellular systems that can be applied in designing more reliable and biocompatible stimulation-based neuroprosthetics.

On M31's Double Nucleus

NASA Technical Reports Server (NTRS)

Miller, R. H.; Smith, B. F.; Cuzzi, Jeffrey (Technical Monitor)

1995-01-01

The recent HST discovery of a double nucleus in M31 brings into prominence the question how long, a second core can survive within the nuclear regions of a galaxy. Physical conditions in the nuclear regions of a typical galaxy help a second core survive, so it can orbit for a long time. possibly for thousands of orbits. Given the nearly uniform mass density in a core, tidal forces within a core radius are compressive in all directions and help the core survive the buffeting it takes as it orbits near the center of the galaxy. We use numerical experiments to illustrate these physical principles. Our method allows the full power of the experiments to be concentrated on the nuclear regions. Spatial resolution of about 0.2 pc comfortably resolves detail within the 1.4 parsec core radius of the second, but brighter core (P1) in M31. We use these physical principles to discuss M31's double nucleus, but they apply to other galaxies as well. and in other astronomical situations such as dumbbell galaxies. galaxies orbiting near the center of a galaxy cluster, and subclustering in galaxy clusters. The experiments also illustrate that galaxy encounters and merging are quite sensitive to external tidal forces, such as those produced by the gravitational potential in a group or cluster of galaxies.

Multiple Core Galaxies: Implications for M31

NASA Technical Reports Server (NTRS)

Smith, B. F.; Miller, R. H.; Cuzzi, Jeffrey N. (Technical Monitor)

1994-01-01

It is generally perceived that two cores cannot survive very long within the nuclear regions of a galaxy. The recent HST discovery of a double nucleus in M31 brings this question into prominence. Physical conditions in the nuclear regions of a typical galaxy help a second core survive so it can orbit for a long time, possibly for thousands of orbits. Given the nearly uniform mass density in a core, tidal forces within a core radius are compressive in all directions and help the core survive the buffeting it takes as it orbits near the center of the galaxy. We use numerical experiments to illustrate these physical principles. Modifications to the experimental method allow the full power of the experiments to be concentrated on the nuclear regions. Spatial resolution of about 0.2 parsec comfortably resolves detail within the 1.4 parsec core radius of the second, but brighter, core (P1) in M31. The same physical principles apply in other astronomical situations, such as dumbbell galaxies, galaxies orbiting near the center of a galaxy cluster, and subclustering in galaxy clusters. The experiments also illustrate that galaxy encounters and merging are quite sensitive to external tidal forces, such as those produced by the gravitational potential in a group or cluster of galaxies.

[Process orientation as a tool of strategic approaches to corporate governance and integrated management systems].

PubMed

Sens, Brigitte

2010-01-01

The concept of general process orientation as an instrument of organisation development is the core principle of quality management philosophy, i.e. the learning organisation. Accordingly, prestigious quality awards and certification systems focus on process configuration and continual improvement. In German health care organisations, particularly in hospitals, this general process orientation has not been widely implemented yet - despite enormous change dynamics and the requirements of both quality and economic efficiency of health care processes. But based on a consistent process architecture that considers key processes as well as management and support processes, the strategy of excellent health service provision including quality, safety and transparency can be realised in daily operative work. The core elements of quality (e.g., evidence-based medicine), patient safety and risk management, environmental management, health and safety at work can be embedded in daily health care processes as an integrated management system (the "all in one system" principle). Sustainable advantages and benefits for patients, staff, and the organisation will result: stable, high-quality, efficient, and indicator-based health care processes. Hospitals with their broad variety of complex health care procedures should now exploit the full potential of total process orientation. Copyright © 2010. Published by Elsevier GmbH.

First-principles study of electronic, optical and thermoelectric properties in cubic perovskite materials AgMO3 (M = V, Nb, Ta)

NASA Astrophysics Data System (ADS)

Mahmood, Asif; Ramay, Shahid M.; Rafique, Hafiz Muhammad; Al-Zaghayer, Yousef; Khan, Salah Ud-Din

2014-05-01

In this paper, first-principles calculations of structural, electronic, optical and thermoelectric properties of AgMO3 (M = V, Nb and Ta) have been carried out using full potential linearized augmented plane wave plus local orbitals method (FP - LAPW + lo) and BoltzTraP code within the framework of density functional theory (DFT). The calculated structural parameters are found to agree well with the experimental data, while the electronic band structure indicates that AgNbO3 and AgTaO3 are semiconductors with indirect bandgaps of 1.60 eV and 1.64 eV, respectively, between the occupied O 2p and unoccupied d states of Nb and Ta. On the other hand, AgVO3 is found metallic due to the overlapping behavior of states across the Fermi level. Furthermore, optical properties, such as dielectric function, absorption coefficient, optical reflectivity, refractive index and extinction coefficient of AgNbO3 and AgTaO3, are calculated for incident photon energy up to 50 eV. Finally, we calculate thermo power for AgNbO3 and AgTaO3 at fixed doping 1019 cm-3. Electron doped thermo power of AgNbO3 shows significant increase over AgTaO3 with temperature.

The Principle of Energetic Consistency

NASA Technical Reports Server (NTRS)

Cohn, Stephen E.

2009-01-01

A basic result in estimation theory is that the minimum variance estimate of the dynamical state, given the observations, is the conditional mean estimate. This result holds independently of the specifics of any dynamical or observation nonlinearity or stochasticity, requiring only that the probability density function of the state, conditioned on the observations, has two moments. For nonlinear dynamics that conserve a total energy, this general result implies the principle of energetic consistency: if the dynamical variables are taken to be the natural energy variables, then the sum of the total energy of the conditional mean and the trace of the conditional covariance matrix (the total variance) is constant between observations. Ensemble Kalman filtering methods are designed to approximate the evolution of the conditional mean and covariance matrix. For them the principle of energetic consistency holds independently of ensemble size, even with covariance localization. However, full Kalman filter experiments with advection dynamics have shown that a small amount of numerical dissipation can cause a large, state-dependent loss of total variance, to the detriment of filter performance. The principle of energetic consistency offers a simple way to test whether this spurious loss of variance limits ensemble filter performance in full-blown applications. The classical second-moment closure (third-moment discard) equations also satisfy the principle of energetic consistency, independently of the rank of the conditional covariance matrix. Low-rank approximation of these equations offers an energetically consistent, computationally viable alternative to ensemble filtering. Current formulations of long-window, weak-constraint, four-dimensional variational methods are designed to approximate the conditional mode rather than the conditional mean. Thus they neglect the nonlinear bias term in the second-moment closure equation for the conditional mean. The principle of energetic consistency implies that, to precisely the extent that growing modes are important in data assimilation, this term is also important.

The foundational principles as psychological lodestars: Theoretical inspiration and empirical direction in rehabilitation psychology.

PubMed

Dunn, Dana S; Ehde, Dawn M; Wegener, Stephen T

2016-02-01

Historically, the Foundational Principles articulated by Wright (1983) and others guided theory development, research and scholarship, and practice in rehabilitation psychology. In recent decades, these principles have become more implicit and less explicit or expressive in the writings and work of rehabilitation professionals. We believe that the Foundational Principles are essential lodestars for working with people with disabilities that can guide inquiry, practice, and service. To introduce this special issues, this commentary identifies and defines key Foundational Principles, including, for example, Lewin's (1935) person-environment relation, adjustment to disability, the malleability of self-perceptions of bodily states, and the importance of promoting dignity for people with disabilities. We then consider the role the Foundational Principles play in the articles appearing in this special issue. We close by considering some new principles and their potential utility in rehabilitation settings. Readers in rehabilitation psychology and aligned areas (e.g., social-personality psychology, health psychology, rehabilitation therapist, psychiatry, and nursing) are encouraged to consider how the Foundational Principles underlie and can shape their research and practice. (c) 2016 APA, all rights reserved).

Gourmet Lab: The Scientific Principles Behind Your Favorite Foods

ERIC Educational Resources Information Center

Young, Sarah

2011-01-01

Hands-on, inquiry-based, and relevant to every student's life, "Gourmet Lab" serves up a full menu of activities for science teachers of grades 6-12. This collection of 15 hands-on experiments--each of which includes a full set of both student and teacher pages--challenges students to take on the role of scientist and chef, as they boil,…

2 CFR Appendix I to Part 200 - Full Text of Notice of Funding Opportunity

Code of Federal Regulations, 2014 CFR

2014-01-01

... PRINCIPLES, AND AUDIT REQUIREMENTS FOR FEDERAL AWARDS Pt. 200, App. I Appendix I to Part 200—Full Text of... section whether that section is required in every announcement or is a Federal awarding agency option. The... sections to describe the types of information that a Federal awarding agency would include in that section...

The Full Purpose Partnership Model for Promoting Academic and Socio-Emotional Success in Schools

ERIC Educational Resources Information Center

Anderson, Jeffrey A.; Houser, John H. W.; Howland, Allison

2010-01-01

In 2003, a partnership between a local system of care and a large urban school district led to the creation of a schoolwide educational model called the Full Purpose Partnership (FPP). This model was implemented in several elementary schools in Indianapolis, Indiana to integrate the principles of systems of care and wraparound with the techniques…

Full and Open Access to Data in the Global Earth Observing System of Systems (GEOSS): Implementing the GEOSS Data Sharing Principles

NASA Astrophysics Data System (ADS)

Chen, R. S.; Uhlir, P. F.; Gabrinowicz, J. I.

2008-12-01

Full and open access to data from remote sensing platforms and other sources can facilitate not only scientific research but also the more widespread and effective use of scientific data for the benefit of society. The Global Earth Observing System of Systems (GEOSS) is a major international initiative of the Group on Earth Observations (GEO) to develop "coordinated, comprehensive and sustained Earth observations and information." In 2005, GEO adopted the GEOSS Data Sharing Principles, which call for the "full and open exchange of data, metadata, and products shared within GEOSS, recognizing relevant international instruments and national policies and legislation." These Principles also note that "All shared data, metadata, and products will be made available with minimum time delay and at minimum cost" and that "All shared data, metadata, and products being free of charge or no more than cost of reproduction will be encouraged for research and education." GEOSS Task DA-06-01, aimed at developing a set of recommended implementation guidelines for the Principles, was established in 2006 under the leadership of CODATA, the Committee on Data for Science and Technology of the International Council for Science (ICSU). An international team of authors has developed a draft White Paper on the GEOSS Data Sharing Principles and a proposed set of implementation guidelines. These have been carefully reviewed by independent reviewers, various GEO Committees, and GEO National Members and Participating Organizations. It is expected that the proposed implementation guidelines will be discussed at the GEO-V Plenary in Budapest in November 2008. The current version of the proposed implementation guidelines recognizes the importance of good faith, voluntary adherence to the Principles by GEO National Members and Participating Organizations. It underscores the value of reuse and re-dissemination of GEOSS data with minimum restrictions, not only within GEOSS itself but on the part of GEOSS users. Consistency with relevant international instruments and applicable policies and legislation is essential, and therefore clarification and coordination of applicable policies and procedures are needed. Pricing of GEOSS data, metadata, and products should be based on the premise that the data and information within GEOSS is a public good for public-interest use in the nine societal benefit areas. Time delays for data access from both operational and research systems should be kept to a minimum, reflecting the norms of the relevant scientific communities or data processing centers. The proposed guidelines also emphasize the need to better define research and education uses and to develop and collect usage metrics and indicators. The draft White Paper provides a more detailed review of past and current data policies related to space-based and spatial data, assesses the implications of the Data Sharing Principles for selected case studies, and discusses a number of other important implementation issues. Successful implementation of the GEOSS Data Sharing Principles is likely to be a critical element in the future effectiveness and value of GEOSS.

Yang-Monti Principle in Bridging Long Ureteral Defects: Cases Report and A Systemic Review.

PubMed

Bao, Jun Sheng; He, Qiqi; Li, Yuzhuo; Shi, Wei; Wu, Gongjin; Yue, Zhongjin

2017-07-02

Ureteric substitution using the Yang-Monti principle was reported as a modification of simple ileal ureter replacement. During April 2013 to June in 2015, 2 patients underwent ileal ureteral substitution using a reconfigured ileal segment of Yang Monti principle in our clinical center. Some slight modifications were made and then follow-up were carried out up to 12 months. For these 2 cases, no significant intra/post-operative complications occurred. In 1 year follow up, serum creatinine (Scr) and blood urea nitrogen (BUN) of both patients decreased to normal.Glomerular filtration rate (GFR), renogram and pyelogram showed a stable split renal function. To better understand the Yang-Monti principle and potential risks and complications, we conduct an systemic review by searching PubMed, Google Scholar and the Cochrane Library database from January 1996 through June 2016. 10 out of 644 publications were identified, which included 269 patients from cohort studies. The most usual indications for Yang-monti therapy were iatrogenic stricture and retroperitoneal fibrosis. Infection and ileus were indicated as themain short time postoperative complications while the fistula and re- strictures happened in long-term. In general,we believe Yang-Monti Principle is a safer and efficient technique for clinical partial and complete ureteral defects if patients and potential risks could be well prepared.

Zen and the Art of Living Mindfully: The Health-Enhancing Potential of Zen Aesthetics.

PubMed

Lomas, T; Etcoff, N; Van Gordon, W; Shonin, E

2017-10-01

Amidst the burgeoning enthusiasm for mindfulness in the West, there is a concern that the largely secular 'de-contextualized' way in which it is being harnessed is denuding it of its potential to improve health and well-being. As such, efforts are underway to 're-contextualize' mindfulness, explicitly drawing on the wider framework of Buddhist ideas and practices in which it was initially developed. This paper aims to contribute to this, doing so by focusing on Zen Buddhism, and in particular on Zen aesthetic principles. The article concentrates on the seven principles identified by Hisamatsu (1971) in his classic text Zen and the Fine Arts: kanso (simplicity); fukinsei (asymmetry); koko (austere sublimity); shizen (naturalness); daisuzoku (freedom from routine); sei-jaku (tranquillity); and yūgen (profound grace). The presence of these principles in works of art is seen as reflecting and communicating insights that are central to Buddhism, such as non-attachment. Moreover, these principles do not only apply to the creation and appreciation of art, but have clear applications for treating health-related issues, and improving quality of life more generally. This paper makes the case that embodying these principles in their lives can help people enhance their psychosomatic well-being, and come to a truer understanding of the essence of mindful living.

Physics of Bacterial Morphogenesis

PubMed Central

Sun, Sean X.; Jiang, Hongyuan

2011-01-01

Summary: Bacterial cells utilize three-dimensional (3D) protein assemblies to perform important cellular functions such as growth, division, chemoreception, and motility. These assemblies are composed of mechanoproteins that can mechanically deform and exert force. Sometimes, small-nucleotide hydrolysis is coupled to mechanical deformations. In this review, we describe the general principle for an understanding of the coupling of mechanics with chemistry in mechanochemical systems. We apply this principle to understand bacterial cell shape and morphogenesis and how mechanical forces can influence peptidoglycan cell wall growth. We review a model that can potentially reconcile the growth dynamics of the cell wall with the role of cytoskeletal proteins such as MreB and crescentin. We also review the application of mechanochemical principles to understand the assembly and constriction of the FtsZ ring. A number of potential mechanisms are proposed, and important questions are discussed. PMID:22126993

41 CFR 102-76.55 - What sustainable development principles must Federal agencies apply to the siting, design, and...

Code of Federal Regulations, 2011 CFR

2011-01-01

... construction of new facilities, which include— (a) Optimizing site potential; (b) Minimizing non-renewable... development principles must Federal agencies apply to the siting, design, and construction of new facilities... Federal agencies apply to the siting, design, and construction of new facilities? In keeping with the...

41 CFR 102-76.55 - What sustainable development principles must Federal agencies apply to the siting, design, and...

Code of Federal Regulations, 2014 CFR

2014-01-01

... construction of new facilities, which include— (a) Optimizing site potential; (b) Minimizing non-renewable... development principles must Federal agencies apply to the siting, design, and construction of new facilities... Federal agencies apply to the siting, design, and construction of new facilities? In keeping with the...

41 CFR 102-76.55 - What sustainable development principles must Federal agencies apply to the siting, design, and...

Code of Federal Regulations, 2012 CFR

2012-01-01

... construction of new facilities, which include— (a) Optimizing site potential; (b) Minimizing non-renewable... development principles must Federal agencies apply to the siting, design, and construction of new facilities... Federal agencies apply to the siting, design, and construction of new facilities? In keeping with the...

41 CFR 102-76.55 - What sustainable development principles must Federal agencies apply to the siting, design, and...

Code of Federal Regulations, 2013 CFR

2013-07-01

... construction of new facilities, which include— (a) Optimizing site potential; (b) Minimizing non-renewable... development principles must Federal agencies apply to the siting, design, and construction of new facilities... Federal agencies apply to the siting, design, and construction of new facilities? In keeping with the...

Fostering Taiwanese Preschoolers' Understanding of the Addition-Subtraction Inverse Principle

ERIC Educational Resources Information Center

Lai, Meng-Lung; Baroody, Arthur J.; Johnson, Amanda R.

2008-01-01

The present research involved gauging preschoolers' learning potential for a key arithmetic concept, the addition-subtraction inverse principle (e.g., 2+1-1=2). Sixty 4- and 5-year-old Taiwanese children from two public preschools serving low- and middle-income families participated in the training experiment. Half were randomly assigned to an…

A Sketch of Politically Liberal Principles of Social Justice in Higher Education

ERIC Educational Resources Information Center

Bull, Barry L.

2012-01-01

In light of the importance and the potential danger of education during childhood for politically liberal societies, the author has devoted much of his professional career to thinking about and formulating the moral principles that should govern such a society's educational institutions. However, this task cannot be accomplished for all such…

Flexibility as a Management Principle in Dementia Care: The Adards Example

ERIC Educational Resources Information Center

Cohen-Mansfield, Jiska; Bester, Allan

2006-01-01

Purpose: Flexibility is an essential ingredient of person-centered care. We illustrate the potential impact of flexibility by portraying a nursing home that uses flexibility in its approach to residents and staff members. Designs and Methods: The paper describes the management strategies, principles, and environmental features used by the Adards…

Harnessing Facebook for Student Engagement in Accounting Education: Guiding Principles for Accounting Students and Educators

ERIC Educational Resources Information Center

Stone, Gerard; Fiedler, Brenton Andrew; Kandunias, Chris

2014-01-01

This paper proposes principles to guide accounting students' and accounting educators' use of Facebook as an educational resource to engage students with their learning. A body of cross-disciplinary research has investigated potential applications of Facebook to invigorate student engagement. Generic guidelines for educators who are contemplating…

Designing Serious Game Interventions for Individuals with Autism.

PubMed

Whyte, Elisabeth M; Smyth, Joshua M; Scherf, K Suzanne

2015-12-01

The design of "Serious games" that use game components (e.g., storyline, long-term goals, rewards) to create engaging learning experiences has increased in recent years. We examine of the core principles of serious game design and examine the current use of these principles in computer-based interventions for individuals with autism. Participants who undergo these computer-based interventions often show little evidence of the ability to generalize such learning to novel, everyday social communicative interactions. This lack of generalized learning may result, in part, from the limited use of fundamental elements of serious game design that are known to maximize learning. We suggest that future computer-based interventions should consider the full range of serious game design principles that promote generalization of learning.

Organic Microcrystal Vibronic Lasers with Full-Spectrum Tunable Output beyond the Franck-Condon Principle.

PubMed

Dong, Haiyun; Zhang, Chunhuan; Liu, Yuan; Yan, Yongli; Hu, Fengqin; Zhao, Yong Sheng

2018-03-12

The very broad emission bands of organic semiconductor materials are, in theory, suitable for achieving versatile solid-state lasers; however, most of organic materials only lase at short wavelength corresponding to the 0-1 transition governed by the Franck-Condon (FC) principle. A strategy is developed to overcome the limit of FC principle for tailoring the output of microlasers over a wide range based on the controlled vibronic emission of organic materials at microcrystal state. For the first time, the output wavelength of organic lasers is tailored across all vibronic (0-1, 0-2, 0-3, and even 0-4) bands spanning the entire emission spectrum. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

The community care model of the Intercountry Centre for Oral Health at Chiangmai, Thailand.

PubMed

Anumanrajadhon, T; Rajchagool, S; Nitisiri, P; Phantumvanit, P; Songpaisan, Y; Barmes, D E; Sardo-Infirri, J; Davies, G N; Møller, I J; Pilot, T

1996-08-01

The Intercountry Centre for Oral Health opened in Chiangmai, Thailand, in November, 1981. In 1984, as part of its mandate to promote new approaches to the delivery of oral health care, it initiated a demonstration project known as the Community Care Model for Oral Health. Logistic, financial and organisational difficulties prevented the full implementation of the original plan. Nevertheless, consideration of the strengths and weaknesses of the Model has provided valuable suggestions for adoption by national and international health agencies interested in adopting a primary health care approach to the delivery of oral health services. Important features which could be appropriate for disadvantaged communities include: integration into the existing health service infrastructure; emphasis on health promotion and prevention; minimal clinical interventions; an in-built monitoring and evaluation system based on epidemiological principles, full community participation in planning and implementation; the establishment of specific targets and goals; the instruction of all health personnel, teachers and senior students in the basic principles of the recognition, prevention and control of oral diseases and conditions; the application of relevant principles of Performance Logic to training; and the provision of a clear career path for all health personnel.

Hyperspectral tomography based on multi-mode absorption spectroscopy (MUMAS)

NASA Astrophysics Data System (ADS)

Dai, Jinghang; O'Hagan, Seamus; Liu, Hecong; Cai, Weiwei; Ewart, Paul

2017-10-01

This paper demonstrates a hyperspectral tomographic technique that can recover the temperature and concentration field of gas flows based on multi-mode absorption spectroscopy (MUMAS). This method relies on the recently proposed concept of nonlinear tomography, which can take full advantage of the nonlinear dependency of MUMAS signals on temperature and enables 2D spatial resolution of MUMAS which is naturally a line-of-sight technique. The principles of MUMAS and nonlinear tomography, as well as the mathematical formulation of the inversion problem, are introduced. Proof-of-concept numerical demonstrations are presented using representative flame phantoms and assuming typical laser parameters. The results show that faithful reconstruction of temperature distribution is achievable when a signal-to-noise ratio of 20 is assumed. This method can potentially be extended to simultaneously reconstructing distributions of temperature and the concentration of multiple flame species.

The evaluation of research papers in the XXI century. The Open Peer Discussion system of the World Economics Association.

PubMed

Ietto-Gillies, Grazia

2012-01-01

The paper starts with a brief discussion of the traditional peer review (TPR) system of research evaluation, its role, and the criticisms levelled at it. An analysis of specific problems in economics leads to a full discussion of the Open Peer Review (OPR) system developed by the World Economics Association (WEA) and the principles behind it. The system is open in the following two respects: (a) disclosure of names of authors and reviewers; and (b) inclusivity of potential reviewers in terms of paradigmatic approaches, country, and community. The paper then discusses the applicability of the same system to other disciplines. In doing so, it stressed the aims of various evaluation systems and the possible pitfalls of rating systems. It also speculates on the future of journal publication.

Quality cell therapy manufacturing by design.

PubMed

Lipsitz, Yonatan Y; Timmins, Nicholas E; Zandstra, Peter W

2016-04-01

Transplantation of live cells as therapeutic agents is poised to offer new treatment options for a wide range of acute and chronic diseases. However, the biological complexity of cells has hampered the translation of laboratory-scale experiments into industrial processes for reliable, cost-effective manufacturing of cell-based therapies. We argue here that a solution to this challenge is to design cell manufacturing processes according to quality-by-design (QbD) principles. QbD integrates scientific knowledge and risk analysis into manufacturing process development and is already being adopted by the biopharmaceutical industry. Many opportunities to incorporate QbD into cell therapy manufacturing exist, although further technology development is required for full implementation. Linking measurable molecular and cellular characteristics of a cell population to final product quality through QbD is a crucial step in realizing the potential for cell therapies to transform healthcare.

Global reaction mechanism for the auto-ignition of full boiling range gasoline and kerosene fuels

NASA Astrophysics Data System (ADS)

Vandersickel, A.; Wright, Y. M.; Boulouchos, K.

2013-12-01

Compact reaction schemes capable of predicting auto-ignition are a prerequisite for the development of strategies to control and optimise homogeneous charge compression ignition (HCCI) engines. In particular for full boiling range fuels exhibiting two stage ignition a tremendous demand exists in the engine development community. The present paper therefore meticulously assesses a previous 7-step reaction scheme developed to predict auto-ignition for four hydrocarbon blends and proposes an important extension of the model constant optimisation procedure, allowing for the model to capture not only ignition delays, but also the evolutions of representative intermediates and heat release rates for a variety of full boiling range fuels. Additionally, an extensive validation of the later evolutions by means of various detailed n-heptane reaction mechanisms from literature has been presented; both for perfectly homogeneous, as well as non-premixed/stratified HCCI conditions. Finally, the models potential to simulate the auto-ignition of various full boiling range fuels is demonstrated by means of experimental shock tube data for six strongly differing fuels, containing e.g. up to 46.7% cyclo-alkanes, 20% napthalenes or complex branched aromatics such as methyl- or ethyl-napthalene. The good predictive capability observed for each of the validation cases as well as the successful parameterisation for each of the six fuels, indicate that the model could, in principle, be applied to any hydrocarbon fuel, providing suitable adjustments to the model parameters are carried out. Combined with the optimisation strategy presented, the model therefore constitutes a major step towards the inclusion of real fuel kinetics into full scale HCCI engine simulations.

A theoretical study of the omega-phase transformation in metals

NASA Astrophysics Data System (ADS)

Sanati, Mahdi

I have studied the formation of o-phase from electronic and mesoscopic (domain wall) points of view. To study the formation of domain walls, I have extended the Landau model of Cook for the o-phase transition by including a spatial gradient (Ginzburg) term of the scalar order parameter. In general, the Landau free energy is an asymmetric double-well potential. From the variational derivative of the total free energy I obtained a static equilibrium condition. By solving this equation for different physical parameters and boundary conditions, I obtained different quasi-one-dimensional soliton-like solutions. These solutions correspond to three different types of domain walls between the o-phase and the beta-matrix. These results are used to model the formation of the o-phase in bcc Ti. Canonical band model and first principles calculations confirmed the instability of the bcc-phase of group III and IV transition metals with respect to the o-phase transformation. I showed that the d-electron density is the controlling parameter for this type of the transformation. Also the possibility of formation of the o-phase for rare earth metals is discussed. First-principles full-potential linear muffin-tin orbital method (FPLMTO) calculations are performed for o-type displacement of the atoms to study the formation of the o-phase in TiAl and Ti 3Al2Nb alloys. The results of my calculations showed an instability in ordered B2 TiAl structure with respect to the o-phase when one third of the Al atoms are replaced by Nb atoms. These phenomena are explained, first by symmetry arguments; then a pair potential model is used to illustrate this instability based on interactions between different pair of atoms derived from the electronic structure. In addition, importance of the atomic arrangements on the structural stability of the Ti3Al2 Nb system is discussed.

Matric potential

Treesearch

Melvin T. Tyree

2003-01-01

Matric potential, r, is a component of water potential, ?, but has different meanings in plant physiology vs. soil science. A rigorous definition of r requires a reference to principles of thermodynamics (both classical and irreversible thermodynamics). A rigorous treatment is beyond the scope of this brief overview. Readers...

A semi-empirical model for the estimation of maximum horizontal displacement due to liquefaction-induced lateral spreading

USGS Publications Warehouse

Faris, Allison T.; Seed, Raymond B.; Kayen, Robert E.; Wu, Jiaer

2006-01-01

During the 1906 San Francisco Earthquake, liquefaction-induced lateral spreading and resultant ground displacements damaged bridges, buried utilities, and lifelines, conventional structures, and other developed works. This paper presents an improved engineering tool for the prediction of maximum displacement due to liquefaction-induced lateral spreading. A semi-empirical approach is employed, combining mechanistic understanding and data from laboratory testing with data and lessons from full-scale earthquake field case histories. The principle of strain potential index, based primary on correlation of cyclic simple shear laboratory testing results with in-situ Standard Penetration Test (SPT) results, is used as an index to characterized the deformation potential of soils after they liquefy. A Bayesian probabilistic approach is adopted for development of the final predictive model, in order to take fullest advantage of the data available and to deal with the inherent uncertainties intrinstiic to the back-analyses of field case histories. A case history from the 1906 San Francisco Earthquake is utilized to demonstrate the ability of the resultant semi-empirical model to estimate maximum horizontal displacement due to liquefaction-induced lateral spreading.

First-principles study of the structural, electronic and thermal properties of CaLiF3

NASA Astrophysics Data System (ADS)

Chouit, N.; Amara Korba, S.; Slimani, M.; Meradji, H.; Ghemid, S.; Khenata, R.

2013-09-01

Density functional theory calculations have been performed to study the structural, electronic and optical properties of CaLiF3 cubic fluoroperovskite. Our calculations were carried out by means of the full-potential linearized augmented plane-wave method. The exchange-correlation potential is treated by the local density approximation and the generalized gradient approximation (GGA) (Perdew, Burke and Ernzerhof). Moreover, the alternative form of GGA proposed by Engel and Vosko is also used for band structure calculations. The calculated total energy versus volume allows us to obtain structural properties such as the lattice constant (a0), bulk modulus (B0) and pressure derivative of the bulk modulus (B'0 ). Band structure, density of states and band gap pressure coefficients are also given. Our calculations show that CaLiF3 has an indirect band gap (R-Γ). Following the quasi-harmonic Debye model, in which the phononic effects are considered, the temperature and pressure effects on the lattice constant, bulk modulus, thermal expansion coefficient, Debye temperature and heat capacities are calculated.

Interfacially Optimized, High Energy Density Nanoparticle-Polymer Composites for Capacitive Energy Storage

NASA Astrophysics Data System (ADS)

Shipman, Joshua; Riggs, Brian; Luo, Sijun; Adireddy, Shiva; Chrisey, Douglas

Energy storage is a green energy technology, however it must be cost effective and scalable to meet future energy demands. Polymer-nanoparticle composites are low cost and potentially offer high energy storage. This is based on the high breakdown strength of polymers and the high dielectric constant of ceramic nanoparticles, but the incoherent nature of the interface between the two components prevents the realization of their combined full potential. We have created inkjet printable nanoparticle-polymer composites that have mitigated many of these interface effects, guided by first principle modelling of the interface. We detail density functional theory modelling of the interface and how it has guided our use in in specific surface functionalizations and other inorganic layers. We have validated our approach by using finite element analysis of the interface. By choosing the correct surface functionalization we are able to create dipole traps which further increase the breakdown strength of our composites. Our nano-scale understanding has allowed us to create the highest energy density composites currently available (>40 J/cm3).

Characterizing and Modulating Brain Circuitry through Transcranial Magnetic Stimulation Combined with Electroencephalography.

PubMed

Farzan, Faranak; Vernet, Marine; Shafi, Mouhsin M D; Rotenberg, Alexander; Daskalakis, Zafiris J; Pascual-Leone, Alvaro

2016-01-01

The concurrent combination of transcranial magnetic stimulation (TMS) with electroencephalography (TMS-EEG) is a powerful technology for characterizing and modulating brain networks across developmental, behavioral, and disease states. Given the global initiatives in mapping the human brain, recognition of the utility of this technique is growing across neuroscience disciplines. Importantly, TMS-EEG offers translational biomarkers that can be applied in health and disease, across the lifespan, and in humans and animals, bridging the gap between animal models and human studies. However, to utilize the full potential of TMS-EEG methodology, standardization of TMS-EEG study protocols is needed. In this article, we review the principles of TMS-EEG methodology, factors impacting TMS-EEG outcome measures, and the techniques for preventing and correcting artifacts in TMS-EEG data. To promote the standardization of this technique, we provide comprehensive guides for designing TMS-EEG studies and conducting TMS-EEG experiments. We conclude by reviewing the application of TMS-EEG in basic, cognitive and clinical neurosciences, and evaluate the potential of this emerging technology in brain research.

Transforming Water Management: an Emerging Promise of Integrated Earth Observations

NASA Astrophysics Data System (ADS)

Lawford, R. G.

2011-12-01

Throughout its history, civilization has relied on technology to facilitate many of its advances. New innovations and technologies have often provided strategic advantages that have led to transformations in institutions, economies and ultimately societies. Observational and information technologies are leading to significant developments in the water sector. After a brief introduction tracing the role of observational technologies in the areas of hydrology and water cycle science, this talk explores the existing and potential contributions of remote sensing data in water resource management around the world. In particular, it outlines the steps being undertaken by the Group on Earth Observations (GEO) and its Water Task to facilitate capacity building efforts in water management using Earth Observations in Asia, Africa and Latin and Caribbean America. Success stories on the benefits of using Earth Observations and applying GEO principles are provided. While GEO and its capacity building efforts are contributing to the transformation of water management through interoperability, data sharing, and capacity building, the full potential of these contributions has not been fully realized because impediments and challenges still remain.

Characterizing and Modulating Brain Circuitry through Transcranial Magnetic Stimulation Combined with Electroencephalography

PubMed Central

Farzan, Faranak; Vernet, Marine; Shafi, Mouhsin M. D.; Rotenberg, Alexander; Daskalakis, Zafiris J.; Pascual-Leone, Alvaro

2016-01-01

The concurrent combination of transcranial magnetic stimulation (TMS) with electroencephalography (TMS-EEG) is a powerful technology for characterizing and modulating brain networks across developmental, behavioral, and disease states. Given the global initiatives in mapping the human brain, recognition of the utility of this technique is growing across neuroscience disciplines. Importantly, TMS-EEG offers translational biomarkers that can be applied in health and disease, across the lifespan, and in humans and animals, bridging the gap between animal models and human studies. However, to utilize the full potential of TMS-EEG methodology, standardization of TMS-EEG study protocols is needed. In this article, we review the principles of TMS-EEG methodology, factors impacting TMS-EEG outcome measures, and the techniques for preventing and correcting artifacts in TMS-EEG data. To promote the standardization of this technique, we provide comprehensive guides for designing TMS-EEG studies and conducting TMS-EEG experiments. We conclude by reviewing the application of TMS-EEG in basic, cognitive and clinical neurosciences, and evaluate the potential of this emerging technology in brain research. PMID:27713691

Electron-phonon coupling and superconductivity in MgB2 under hydrostatic pressure.

NASA Astrophysics Data System (ADS)

Quijano, Ramiro; Aguayo, Aaron

2005-03-01

We have studied the dynamics and coupling of the E2g phonon mode with the σ-band in MgB2 under pressure using the Frozen Phonon Approximation. The results were obtained by means of first-principles total-energy calculations using the full potential Linearized Augmented Plane Wave (LAPW) method and the Generalized Gradient Approximation (GGA) for the exchange-correlation potential. We present results for the evolution of the anharmonicity and phonon frequency of the E2g mode, the electron-phonon coupling constant, and Tc as a function of hydrostatic pressure in the range 0-40 GPa. We find that the phonon frequency increases monotonically with pressure, but the the anharmonicity, the electron-phonon coupling and Tc decreases with pressure. We have obtained a very good agreement between the calculated Tc(P) and the experimental data available in the literature, in particular with the experimental data corresponding to monocystalline samples. This work was supported by Consejo Nacional de Ciencia y Tecnolog'ia (CONACYT, M'exico) under Grant No. 43830-F.

First-Principles Study of the Electronic Structure and Bonding Properties of X8C46 and X8B6C40 (X: Li, Na, Mg, Ca) Carbon Clathrates

NASA Astrophysics Data System (ADS)

KoleŻyński, Andrzej; Szczypka, Wojciech

2016-03-01

Results from theoretical analysis of the crystal structure, electronic structure, and bonding properties of C46 and B6C40 carbon clathrates doped with selected alkali and alkaline earth metals cations (Li, Na, Mg, Ca) are presented. The ab initio calculations were performed by means of the WIEN2k package (full potential linearized augmented plane wave method (FP-LAPW) within density functional theory (DFT)) with PBESol and modified Becke-Johnson exchange-correlation potentials used in geometry optimization and electronic structure calculations, respectively. The bonding properties were analyzed by applying Bader's quantum theory of atoms in molecules formalism to the topological properties of total electron density obtained from ab initio calculations. Analysis of the results obtained (i.a. equilibrium geometry, equation of state, cohesive energy, band structure, density of states—both total and projected on to particular atoms, and topological properties of bond critical points and net charges of topological atoms) is presented in detail.

Improvement of electronic and thermoelectric properties of the metallic LaS by sodium substitution: From first-principles calculations

NASA Astrophysics Data System (ADS)

Si Mohammed, D. E.; Seddik, T.; Batouche, M.; Merabiha, O.; Zanoun, A.

2018-03-01

In this manuscript, the structural, electronic, and thermoelectric properties of Na doped binary LaS have been studied by means of the full-potential augmented plane wave plus local orbital's method. The Wu-Cohen generalized gradient and the Tran-Blaha modified Becke-Johnson (TB-mBJ) approximations have been employed to describe the exchange-correlation potential. Examining the composition effect on the electronic properties, we point out that LaS compound and Na0.25La0.75S alloy have a metallic behavior. On the other hand, both Na0.5La0.5S and Na0.75La0.25S alloys show a semiconductor behavior with direct bandgap equal to 1.26 and 2.8 eV, using the TB-mBJ approximation, respectively. Moreover, the thermoelectric properties of LaS are enhanced, especially for 50% and 75% of Na concentration. Consequently, the estimated ZT value of about 0.75 at room temperature proves that Na doped metal LaS makes it a promising candidate for thermoelectric applications.

On evolutionary systems.

PubMed

Alvarez de Lorenzana, J M; Ward, L M

1987-01-01

This paper develops a metatheoretical framework for understanding evolutionary systems (systems that develop in ways that increase their own variety). The framework addresses shortcomings seen in other popular systems theories. It concerns both living and nonliving systems, and proposes a metahierarchy of hierarchical systems. Thus, it potentially addresses systems at all descriptive levels. We restrict our definition of system to that of a core system whose parts have a different ontological status than the system, and characterize the core system in terms of five global properties: minimal length interval, minimal time interval, system cycle, total receptive capacity, and system potential. We propose two principles through the interaction of which evolutionary systems develop. The Principle of Combinatorial Expansion describes how a core system realizes its developmental potential through a process of progressive differentiation of the single primal state up to a limit stage. The Principle of Generative Condensation describes how the components of the last stage of combinatorial expansion condense and become the environment for and components of new, enriched systems. The early evolution of the Universe after the "big bang" is discussed in light of these ideas as an example of the application of the framework.

Search for Effects of an Electrostatic Potential on Clocks in the Frame of Reference of a Charged Particle

NASA Technical Reports Server (NTRS)

Ringermacher, Harry I.; Conradi, Mark S.; Cassenti, Brice

2005-01-01

Results of experiments to confirm a theory that links classical electromagnetism with the geometry of spacetime are described. The theory, based on the introduction of a Torsion tensor into Einstein s equations and following the approach of Schroedinger, predicts effects on clocks attached to charged particles, subject to intense electric fields, analogous to the effects on clocks in a gravitational field. We show that in order to interpret this theory, one must re-interpret all clock changes, both gravitational and electromagnetic, as arising from changes in potential energy and not merely potential. The clock is provided naturally by proton spins in hydrogen atoms subject to Nuclear Magnetic Resonance trials. No frequency change of clocks was observed to a resolution of 6310(exp -9). A new "Clock Principle" was postulated to explain the null result. There are two possible implications of the experiments: (a) The Clock Principle is invalid and, in fact, no metric theory incorporating electromagnetism is possible; (b) The Clock Principle is valid and it follows that a negative rest mass cannot exist.

Patient safety principles in family medicine residency accreditation standards and curriculum objectives

PubMed Central

Kassam, Aliya; Sharma, Nishan; Harvie, Margot; O’Beirne, Maeve; Topps, Maureen

2016-01-01

Abstract Objective To conduct a thematic analysis of the College of Family Physicians of Canada’s (CFPC’s) Red Book accreditation standards and the Triple C Competency-based Curriculum objectives with respect to patient safety principles. Design Thematic content analysis of the CFPC’s Red Book accreditation standards and the Triple C curriculum. Setting Canada. Main outcome measures Coding frequency of the patient safety principles (ie, patient engagement; respectful, transparent relationships; complex systems; a just and trusting culture; responsibility and accountability for actions; and continuous learning and improvement) found in the analyzed CFPC documents. Results Within the analyzed CFPC documents, the most commonly found patient safety principle was patient engagement (n = 51 coding references); the least commonly found patient safety principles were a just and trusting culture (n = 5 coding references) and complex systems (n = 5 coding references). Other patient safety principles that were uncommon included responsibility and accountability for actions (n = 7 coding references) and continuous learning and improvement (n = 12 coding references). Conclusion Explicit inclusion of patient safety content such as the use of patient safety principles is needed for residency training programs across Canada to ensure the full spectrum of care is addressed, from community-based care to acute hospital-based care. This will ensure a patient safety culture can be cultivated from residency and sustained into primary care practice. PMID:27965349

2015/2016 Quality Risk Management Benchmarking Survey.

PubMed

Waldron, Kelly; Ramnarine, Emma; Hartman, Jeffrey

2017-01-01

This paper investigates the concept of quality risk management (QRM) maturity as it applies to the pharmaceutical and biopharmaceutical industries, using the results and analysis from a QRM benchmarking survey conducted in 2015 and 2016. QRM maturity can be defined as the effectiveness and efficiency of a quality risk management program, moving beyond "check-the-box" compliance with guidelines such as ICH Q9 Quality Risk Management , to explore the value QRM brings to business and quality operations. While significant progress has been made towards full adoption of QRM principles and practices across industry, the full benefits of QRM have not yet been fully realized. The results of the QRM Benchmarking Survey indicate that the pharmaceutical and biopharmaceutical industries are approximately halfway along the journey towards full QRM maturity. LAY ABSTRACT: The management of risks associated with medicinal product quality and patient safety are an important focus for the pharmaceutical and biopharmaceutical industries. These risks are identified, analyzed, and controlled through a defined process called quality risk management (QRM), which seeks to protect the patient from potential quality-related risks. This paper summarizes the outcomes of a comprehensive survey of industry practitioners performed in 2015 and 2016 that aimed to benchmark the level of maturity with regard to the application of QRM. The survey results and subsequent analysis revealed that the pharmaceutical and biopharmaceutical industries have made significant progress in the management of quality risks over the last ten years, and they are roughly halfway towards reaching full maturity of QRM. © PDA, Inc. 2017.

10 ways to create shareholder value.

PubMed

Rappaport, Alfred

2006-09-01

Executives have developed tunnel vision in their pursuit of shareholder value, focusing on short-term performance at the expense of investing in long-term growth. It's time to broaden that perspective and begin shaping business strategies in light of the competitive landscape, not the shareholder list. In this article, Alfred Rappaport offers ten basic principles to help executives create lasting shareholder value. For starters, companies should not manage earnings or provide earnings guidance; those that fail to embrace this first principle of shareholder value will almost certainly be unable to follow the rest. Additionally, leaders should make strategic decisions and acquisitions and carry assets that maximize expected value, even if near-term earnings are negatively affected as a result. During times when there are no credible value-creating opportunities to invest in the business, companies should avoid using excess cash to make investments that look good on the surface but might end up destroying value, such as ill-advised, overpriced acquisitions. It would be better to return the cash to shareholders in the form of dividends and buybacks. Rappaport also offers guidelines for establishing effective pay incentives at every level of management; emphasizes that senior executives need to lay their wealth on the line just as shareholders do; and urges companies to embrace full disclosure, an antidote to short-term earnings obsession that serves to lessen investor uncertainty, which could reduce the cost of capital and increase the share price. The author notes that a few types of companies--high-tech start-ups, for example, and severely capital-constrained organizations--cannot afford to ignore market pressures for short-term performance. Most companies with a sound, well-executed business model, however, could better realize their potential for creating shareholder value by adopting the ten principles.

Analysis of magnetic fields using variational principles and CELAS2 elements

NASA Technical Reports Server (NTRS)

Frye, J. W.; Kasper, R. G.

1977-01-01

Prospective techniques for analyzing magnetic fields using NASTRAN are reviewed. A variational principle utilizing a vector potential function is presented which has as its Euler equations, the required field equations and boundary conditions for static magnetic fields including current sources. The need for an addition to this variational principle of a constraint condition is discussed. Some results using the Lagrange multiplier method to apply the constraint and CELAS2 elements to simulate the matrices are given. Practical considerations of using large numbers of CELAS2 elements are discussed.

Action principle for Coulomb collisions in plasmas

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

Hirvijoki, Eero

In this study, an action principle for Coulomb collisions in plasmas is proposed. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth-MacDonald-Judd potentials. Conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles.

Gamification: What It Is and Why It Matters to Digital Health Behavior Change Developers

PubMed Central

2013-01-01

This editorial provides a behavioral science view on gamification and health behavior change, describes its principles and mechanisms, and reviews some of the evidence for its efficacy. Furthermore, this editorial explores the relation between gamification and behavior change frameworks used in the health sciences and shows how gamification principles are closely related to principles that have been proven to work in health behavior change technology. Finally, this editorial provides criteria that can be used to assess when gamification provides a potentially promising framework for digital health interventions. PMID:25658754

Gamification: what it is and why it matters to digital health behavior change developers.

PubMed

Cugelman, Brian

2013-12-12

This editorial provides a behavioral science view on gamification and health behavior change, describes its principles and mechanisms, and reviews some of the evidence for its efficacy. Furthermore, this editorial explores the relation between gamification and behavior change frameworks used in the health sciences and shows how gamification principles are closely related to principles that have been proven to work in health behavior change technology. Finally, this editorial provides criteria that can be used to assess when gamification provides a potentially promising framework for digital health interventions.

Action principle for Coulomb collisions in plasmas

DOE PAGES

Hirvijoki, Eero

2016-09-14

In this study, an action principle for Coulomb collisions in plasmas is proposed. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth-MacDonald-Judd potentials. Conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles.

Teaching/learning principles

NASA Technical Reports Server (NTRS)

Hankins, D. B.; Wake, W. H.

1981-01-01

The potential remote sensing user community is enormous, and the teaching and training tasks are even larger; however, some underlying principles may be synthesized and applied at all levels from elementary school children to sophisticated and knowledgeable adults. The basic rules applying to each of the six major elements of any training course and the underlying principle involved in each rule are summarized. The six identified major elements are: (1) field sites for problems and practice; (2) lectures and inside study; (3) learning materials and resources (the kit); (4) the field experience; (5) laboratory sessions; and (6) testing and evaluation.

Translating Human Rights Principles into Classroom Practices: Inequities in Educating about Human Rights

ERIC Educational Resources Information Center

Robinson, Carol

2017-01-01

The overarching aim of this paper is to explore how key principles inherent in human rights declarations and conventions are translated into practices associated with human rights education within school contexts. It is argued that this translation from discourse to practice opens up the potential for children and young people to encounter…

Designing for Success: Developing Engineers Who Consider Universal Design Principles

ERIC Educational Resources Information Center

Bigelow, Kimberly Edginton

2012-01-01

Engineers must design for a diverse group of potential users of their products; however, engineering curricula rarely include an emphasis on universal design principles. This research article details the effectiveness of a design project implemented in a first-year engineering course in an effort to raise awareness of the need for engineers to be…

Translating Principles of Neural Plasticity into Research on Speech Motor Control Recovery and Rehabilitation

ERIC Educational Resources Information Center

Ludlow, Christy L.; Hoit, Jeannette; Kent, Raymond; Ramig, Lorraine O.; Shrivastav, Rahul; Strand, Edythe; Yorkston, Kathryn; Sapienza, Christine M.

2008-01-01

Purpose: To review the principles of neural plasticity and make recommendations for research on the neural bases for rehabilitation of neurogenic speech disorders. Method: A working group in speech motor control and disorders developed this report, which examines the potential relevance of basic research on the brain mechanisms involved in neural…

Implementation of the Biosphere Compatibility Principle in Urban Planning: How to Train Next-Generation Specialists

ERIC Educational Resources Information Center

Ivanova, Zinaida Ilyinichna; Yudenkova, Olga Valeryevna; Ishkov, Aleksandr Dmitrievich; Shnyrenkov, Evgeny Anatolyevich

2015-01-01

The co-authors address the relevant issues concerning the need to implement the principle of the biosphere compatibility as the core prerequisite for the symbiotic co-existence of man and nature. Caring treatment of the biosphere, termination of its excessive exploitation, analysis of the ratio between the biospheric potential of specific areas…

'Learn the signs. Act early': a campaign to help every child reach his or her full potential.

PubMed

Daniel, K L; Prue, C; Taylor, M K; Thomas, J; Scales, M

2009-09-01

To examine the application of a social marketing approach to increase the early identification and treatment of autism and other developmental disorders. The intervention used formative research, behaviour change theory and traditional social marketing techniques to develop a campaign targeting parents, healthcare professionals and early educators to increase awareness of autism and other developmental delays, and to prompt action if a developmental delay was suspected. Using social marketing principles, the Centers for Disease Control and Prevention applied baseline research with the target audiences to understand the barriers and motivators to behaviour change, which included a lack of knowledge and resources (barriers), along with a willingness to learn and do more (motivators). Focus group testing of potential campaign concepts led to one particular approach and accompanying images, which together increased perceived severity of the problem and encouraged taking action. The audience research also helped to shape the marketing mix (product, price, place and promotion). Three-year follow-up research in this case study indicates a significant change in parent target behaviours, particularly among parents aware of the campaign, and substantially more healthcare professionals believe that they have the resources to educate parents about monitoring their child's cognitive, social and physical development. Qualitative results from early educators and childcare professional associations have been positive about products developed for daycare settings. The application of social marketing principles, behavior change theory and audience research was an effective approach to changing behaviours in this case. Understanding what the target audiences want and need, looking beyond parents to engage healthcare professionals and early educators, and engaging many strategic partners to extend the reach of the message helped campaign planners to develop a campaign that resonated with the target audiences and, importantly, moved them towards action.

Electromagnetic finite elements based on a four-potential variational principle

NASA Technical Reports Server (NTRS)

Schuler, James J.; Felippa, Carlos A.

1991-01-01

Electromagnetic finite elements based on a variational principle that uses the electromagnetic four-potential as a primary variable are derived. This choice is used to construct elements suitable for downstream coupling with mechanical and thermal finite elements for the analysis of electromagnetic/mechanical systems that involve superconductors. The main advantages of the four-potential as a basis for finite element formulation are that the number of degrees of freedom per node remains modest as the problem dimensionally increases, that jump discontinuities on interfaces are naturally accommodated, and that statics as well as dynamics may be treated without any a priori approximations. The new elements are tested on an axisymmetric problem under steady state forcing conditions. The results are in excellent agreement with analytical solutions.

Ethnography: principles, practice and potential.

PubMed

Draper, Jan

2015-05-06

Ethnography is a methodology that is gaining popularity in nursing and healthcare research. It is concerned with studying people in their cultural context and how their behaviour, either as individuals or as part of a group, is influenced by this cultural context. Ethnography is a form of social research and has much in common with other forms of qualitative enquiry. While classical ethnography was characteristically concerned with describing 'other' cultures, contemporary ethnography has focused on settings nearer to home. This article outlines some of the underlying principles and practice of ethnography, and its potential for nursing and healthcare practice.

A first principles prediction of the crystal structure of C6Br2ClFH2

NASA Astrophysics Data System (ADS)

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

2008-04-01

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

Vector potential methods

NASA Technical Reports Server (NTRS)

Hafez, M.

1989-01-01

Vector potential and related methods, for the simulation of both inviscid and viscous flows over aerodynamic configurations, are briefly reviewed. The advantages and disadvantages of several formulations are discussed and alternate strategies are recommended. Scalar potential, modified potential, alternate formulations of Euler equations, least-squares formulation, variational principles, iterative techniques and related methods, and viscous flow simulation are discussed.

A precautionary principle for dual use research in the life sciences.

PubMed

Kuhlau, Frida; Höglund, Anna T; Evers, Kathinka; Eriksson, Stefan

2011-01-01

Most life science research entails dual-use complexity and may be misused for harmful purposes, e.g. biological weapons. The Precautionary Principle applies to special problems characterized by complexity in the relationship between human activities and their consequences. This article examines whether the principle, so far mainly used in environmental and public health issues, is applicable and suitable to the field of dual-use life science research. Four central elements of the principle are examined: threat, uncertainty, prescription and action. Although charges against the principle exist - for example that it stifles scientific development, lacks practical applicability and is poorly defined and vague - the analysis concludes that a Precautionary Principle is applicable to the field. Certain factors such as credibility of the threat, availability of information, clear prescriptive demands on responsibility and directives on how to act, determine the suitability and success of a Precautionary Principle. Moreover, policy-makers and researchers share a responsibility for providing and seeking information about potential sources of harm. A central conclusion is that the principle is meaningful and useful if applied as a context-dependent moral principle and allowed flexibility in its practical use. The principle may then inspire awareness-raising and the establishment of practical routines which appropriately reflect the fact that life science research may be misused for harmful purposes. © 2009 Blackwell Publishing Ltd.

Test processing system (SEE)

NASA Technical Reports Server (NTRS)

Gaulene, P.

1986-01-01

The SEE data processing system, developed in 1985, manages and process test results. General information is provided on the SEE system: objectives, characteristics, basic principles, general organization, and operation. Full documentation is accessible by computer using the HELP SEE command.

17 CFR Appendix B to Part 37 - Guidance on, and Acceptable Practices in, Compliance with Core Principles

Code of Federal Regulations, 2014 CFR

2014-04-01

... should include full customer restitution where customer harm is demonstrated, except where the amount of... or external audit findings, self-reported errors, or through validated complaints. (C) Requirements...

Parametric normalization for full-energy peak efficiency of HPGe γ-ray spectrometers at different counting positions for bulky sources.

PubMed

Peng, Nie; Bang-Fa, Ni; Wei-Zhi, Tian

2013-02-01

Application of effective interaction depth (EID) principle for parametric normalization of full energy peak efficiencies at different counting positions, originally for quasi-point sources, has been extended to bulky sources (within ∅30 mm×40 mm) with arbitrary matrices. It is also proved that the EID function for quasi-point source can be directly used for cylindrical bulky sources (within ∅30 mm×40 mm) with the geometric center as effective point source for low atomic number (Z) and low density (D) media and high energy γ-rays. It is also found that in general EID for bulky sources is dependent upon Z and D of the medium and the energy of the γ-rays in question. In addition, the EID principle was theoretically verified by MCNP calculations. Copyright © 2012 Elsevier Ltd. All rights reserved.

Trials of Intervention Principles: Evaluation Methods for Evolving Behavioral Intervention Technologies

PubMed Central

Schueller, Stephen M; Riley, William T; Brown, C Hendricks; Cuijpers, Pim; Duan, Naihua; Kwasny, Mary J; Stiles-Shields, Colleen; Cheung, Ken

2015-01-01

In recent years, there has been increasing discussion of the limitations of traditional randomized controlled trial (RCT) methodologies for the evaluation of eHealth and mHealth interventions, and in particular, the requirement that these interventions be locked down during evaluation. Locking down these interventions locks in defects and eliminates the opportunities for quality improvement and adaptation to the changing technological environment, often leading to validation of tools that are outdated by the time that trial results are published. Furthermore, because behavioral intervention technologies change frequently during real-world deployment, even if a tested intervention were deployed in the real world, its shelf life would be limited. We argue that RCTs will have greater scientific and public health value if they focus on the evaluation of intervention principles (rather than a specific locked-down version of the intervention), allowing for ongoing quality improvement modifications to the behavioral intervention technology based on the core intervention principles, while continuously improving the functionality and maintaining technological currency. This paper is an initial proposal of a framework and methodology for the conduct of trials of intervention principles (TIPs) aimed at minimizing the risks of in-trial changes to intervention technologies and maximizing the potential for knowledge acquisition. The focus on evaluation of intervention principles using clinical and usage outcomes has the potential to provide more generalizable and durable information than trials focused on a single intervention technology. PMID:26155878

Trials of Intervention Principles: Evaluation Methods for Evolving Behavioral Intervention Technologies.

PubMed

Mohr, David C; Schueller, Stephen M; Riley, William T; Brown, C Hendricks; Cuijpers, Pim; Duan, Naihua; Kwasny, Mary J; Stiles-Shields, Colleen; Cheung, Ken

2015-07-08

In recent years, there has been increasing discussion of the limitations of traditional randomized controlled trial (RCT) methodologies for the evaluation of eHealth and mHealth interventions, and in particular, the requirement that these interventions be locked down during evaluation. Locking down these interventions locks in defects and eliminates the opportunities for quality improvement and adaptation to the changing technological environment, often leading to validation of tools that are outdated by the time that trial results are published. Furthermore, because behavioral intervention technologies change frequently during real-world deployment, even if a tested intervention were deployed in the real world, its shelf life would be limited. We argue that RCTs will have greater scientific and public health value if they focus on the evaluation of intervention principles (rather than a specific locked-down version of the intervention), allowing for ongoing quality improvement modifications to the behavioral intervention technology based on the core intervention principles, while continuously improving the functionality and maintaining technological currency. This paper is an initial proposal of a framework and methodology for the conduct of trials of intervention principles (TIPs) aimed at minimizing the risks of in-trial changes to intervention technologies and maximizing the potential for knowledge acquisition. The focus on evaluation of intervention principles using clinical and usage outcomes has the potential to provide more generalizable and durable information than trials focused on a single intervention technology.

Stakeholders' Perspectives on Stakeholder-engaged Research (SER): Strategies to Operationalize Patient-centered Outcomes Research Principles for SER.

PubMed

Mackie, Thomas I; Sheldrick, Radley C; de Ferranti, Sarah D; Saunders, Tully; Rojas, Erick G; Leslie, Laurel K

2017-01-01

US federal funding agencies increasingly incentivize stakeholder-engaged research which represents a paradigm shift toward incorporating a range of stakeholders in research design, conduct, and dissemination. We use qualitative methods to capture experience-based recommendations on how to operationalize 4 Patient-Centered Outcomes Research (PCOR) principles in stakeholder-engaged research, specifically: (1) reciprocal relationships; (2) colearning; (3) partnership; and (4) trust, transparency, and honesty. We conducted semistructured interviews with members of a stakeholder panel who participated in a 2-year comparative effectiveness study of cholesterol screening and treatment among young adults. Participants included 8 young adults and parent panelists and 11 professional panelists (clinicians, researchers, policy developers, and disseminators). The interview guide included questions about the 4 PCOR principles and queried preferred strategies to attain them. Interview transcripts were analyzed using an a priori and emergent coding structure. Participants provided strategies to promote the 4 PCOR principles. Although some stakeholder-identified strategies were complementary, others conflicted due to (1) competing ideologies identified among the principles, and (2) distinct stakeholder preferences. Illustrative of competing ideologies, participants simultaneously preferred receiving relevant articles before calls (to facilitate colearning) but also minimal outside reading (to achieve partnership). Illustrative of distinct stakeholder preferences, young adult and parent panelists generally preferred calls to occur on weekends/evenings, whereas professional panelists preferred mid-week work hours. Our exploratory study provides stakeholder-identified strategies to achieve the 4 PCOR principles, and demonstrates the need to identify, acknowledge, and address potentially conflicting strategies due to the potential for competing ideologies or variation in stakeholder preferences.

First-principles theory of iron up to earth-core pressures: Structural, vibrational, and elastic properties

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

Soederlind, P.; Moriarty, J.A.; Wills, J.M.

1996-06-01

{ital Ab} {ital initio} electronic-structure calculations, based on density-functional theory and a full-potential linear-muffin-tin-orbital method, have been used to predict crystal-structure phase stabilities, elastic constants, and Brillouin-zone-boundary phonons for iron under compression. Total energies for five crystal structures, bcc, fcc, bct, hcp, and dhcp, have been calculated over a wide volume range. In agreement with experiment and previous theoretical calculations, a magnetic bcc ground state is obtained at ambient pressure and a nonmagnetic hcp ground state is found at high pressure, with a predicted bcc {r_arrow} hcp phase transition at about 10 GPa. Also in agreement with very recent diamond-anvil-cellmore » experiments, a metastable dhcp phase is found at high pressure, which remains magnetic and consequently accessible at high temperature up to about 50 GPa. In addition, the bcc structure becomes mechanically unstable at pressures above 2 Mbar (200 GPa) and a metastable, but still magnetic, bct phase ({ital c}/{ital a} {approx_equal} 0.875) develops. For high-pressure nonmagnetic iron, fcc and hcp elastic constants and fcc phonon frequencies have been calculated to above 4 Mbar. These quantities rise smoothly with pressure, but an increasing tendency towards elastic anisotropy as a function of compression is observed, and this has important implications for the solid inner-core of the earth. The fcc elastic-constant and phonon data have also been used in combination with generalized pseudopotential theory to develop many-body interatomic potentials, from which high-temperature thermodynamic properties and melting can be obtained. In this paper, these potentials have been used to calculate full fcc and hcp phonon spectra and corresponding Debye temperatures as a function of compression. {copyright} {ital 1996 The American Physical Society.}« less

Efficient and Effective Change Principles in Active Videogames

PubMed Central

Fenner, Ashley A.; Howie, Erin K.; Feltz, Deborah L.; Gray, Cindy M.; Lu, Amy Shirong; Mueller, Florian “Floyd”; Simons, Monique; Barnett, Lisa M.

2015-01-01

Abstract Active videogames have the potential to enhance population levels of physical activity but have not been successful in achieving this aim to date. This article considers a range of principles that may be important to the design of effective and efficient active videogames from diverse discipline areas, including behavioral sciences (health behavior change, motor learning, and serious games), business production (marketing and sales), and technology engineering and design (human–computer interaction/ergonomics and flow). Both direct and indirect pathways to impact on population levels of habitual physical activity are proposed, along with the concept of a game use lifecycle. Examples of current active and sedentary electronic games are used to understand how such principles may be applied. Furthermore, limitations of the current usage of theoretical principles are discussed. A suggested list of principles for best practice in active videogame design is proposed along with suggested research ideas to inform practice to enhance physical activity. PMID:26181680

Efficient and Effective Change Principles in Active Videogames.

PubMed

Straker, Leon M; Fenner, Ashley A; Howie, Erin K; Feltz, Deborah L; Gray, Cindy M; Lu, Amy Shirong; Mueller, Florian Floyd; Simons, Monique; Barnett, Lisa M

2015-02-01

Active videogames have the potential to enhance population levels of physical activity but have not been successful in achieving this aim to date. This article considers a range of principles that may be important to the design of effective and efficient active videogames from diverse discipline areas, including behavioral sciences (health behavior change, motor learning, and serious games), business production (marketing and sales), and technology engineering and design (human-computer interaction/ergonomics and flow). Both direct and indirect pathways to impact on population levels of habitual physical activity are proposed, along with the concept of a game use lifecycle. Examples of current active and sedentary electronic games are used to understand how such principles may be applied. Furthermore, limitations of the current usage of theoretical principles are discussed. A suggested list of principles for best practice in active videogame design is proposed along with suggested research ideas to inform practice to enhance physical activity.

Fluorescent-protein-based probes: general principles and practices.

PubMed

Ai, Hui-Wang

2015-01-01

An important application of fluorescent proteins is to derive genetically encoded fluorescent probes that can actively respond to cellular dynamics such as pH change, redox signaling, calcium oscillation, enzyme activities, and membrane potential. Despite the large diverse group of fluorescent-protein-based probes, a few basic principles have been established and are shared by most of these probes. In this article, the focus is on these general principles and strategies that guide the development of fluorescent-protein-based probes. A few examples are provided in each category to illustrate the corresponding principles. Since these principles are quite straightforward, others may adapt them to create fluorescent probes for their own interest. Hopefully, the development of the ever-growing family of fluorescent-protein-based probes will no longer be limited to a small number of laboratories specialized in senor development, leading to the situation that biological studies will be bettered assisted by genetically encoded sensors.

"Paradigm Change" or No Real Change at All? A Critical Reading of the U.N. Principles for Responsible Management Education

ERIC Educational Resources Information Center

Louw, Jonathan

2015-01-01

Proponents of the transformative potential of the United Nations Principles for Responsible Management Education (PRME) claim that their adoption could lead to a "paradigm change" in business schools, thus addressing many of the sustained critiques of the sector in recent years. However, this claim and the PRME themselves have to date…

Moss-Burstein shift in La-doped BaSnO3; A novel electron transport layer material for hybrid halide perovskite solar cells

NASA Astrophysics Data System (ADS)

Taya, Ankur; Rani, Priti; Kashyap, Manish K.

2018-04-01

Highly efficient hybrid (organic-inorganic) halide perovskite solar cells (PSCs) employ TiO2 as electron transport layer (ETL) but it impedes the device stability under solar illumination. Therefore, there is an imperative need to study the materials that can be the ideal replacement for TiO2 as ETL. With its growth at mild conditions recently by Shin et al. [Science, 356, 167 (2017)], La-doped BaSnO3 (LBSO) emerges out as an efficient candidate for ETL in PSCs. In this direction, we represent first-principles electronic properties and optical response of pristine and La-doped BaSnO3 using full potential linear augmented plane wave (FPLAPW) method within time efficient orbital independent modified Becke Johnson (mBJ) approach. Post La-doping, Moss-Burtsein shift is observed in BaSnO3 that establishes it as an excellent n-type transparent conducting oxide. The optical absorption spectra of LBSO has been analyzed to prove almost full transmittivity for energy ≤ 4eV which affirms LBSO as an ideal material for ETL in various PSCs.

Note on measuring electronic stopping of slow ions

NASA Astrophysics Data System (ADS)

Sigmund, P.; Schinner, A.

2017-11-01

Extracting stopping cross sections from energy-loss measurements requires careful consideration of the experimental geometry. Standard procedures for separating nuclear from electronic stopping treat electronic energy loss as a friction force, ignoring its dependence on impact parameter. In the present study we find that incorporating this dependence has a major effect on measured stopping cross sections, in particular for light ions at low beam energies. Calculations have been made for transmission geometry, nuclear interactions being quantified by Bohr-Williams theory of multiple scattering on the basis of a Thomas-Fermi-Molière potential, whereas electronic interactions are characterized by Firsov theory or PASS code. Differences between the full and the restricted stopping cross section depend on target thickness and opening angle of the detector and need to be taken into account in comparisons with theory as well as in applications of stopping data. It follows that the reciprocity principle can be violated when checked on restricted instead of full electronic stopping cross sections. Finally, we assert that a seeming gas-solid difference in stopping of low-energy ions is actually a metal-insulator difference. In comparisons with experimental results we mostly consider proton data, where nuclear stopping is only a minor perturbation.

Stable isomers and electronic, vibrational, and optical properties of WS2 nano-clusters: A first-principles study

NASA Astrophysics Data System (ADS)

Hafizi, Roohollah; Hashemifar, S. Javad; Alaei, Mojtaba; Jangrouei, MohammadReza; Akbarzadeh, Hadi

2016-12-01

In this paper, we employ an evolutionary algorithm along with the full-potential density functional theory (DFT) computations to perform a comprehensive search for the stable structures of stoichiometric (WS2)n nano-clusters (n = 1 - 9), within three different exchange-correlation functionals. Our results suggest that n = 5 and 8 are possible candidates for the low temperature magic sizes of WS2 nano-clusters while at temperatures above 500 Kelvin, n = 7 exhibits a comparable relative stability with n = 8. The electronic properties and energy gap of the lowest energy isomers were computed within several schemes, including semilocal Perdew-Burke-Ernzerhof and Becke-Lee-Yang-Parr functionals, hybrid B3LYP functional, many body based DFT+GW approach, ΔSCF method, and time dependent DFT calculations. Vibrational spectra of the lowest lying isomers, computed by the force constant method, are used to address IR spectra and thermal free energy of the clusters. Time dependent density functional calculation in a real time domain is applied to determine the full absorption spectra and optical gap of the lowest energy isomers of the WS2 nano-clusters.

AZO/Ag/AZO anode for resonant cavity red, blue, and yellow organic light emitting diodes

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

Gentle, A. R., E-mail: angus.gentle@uts.edu.au; Smith, G. B.; Yambem, S. D.

Indium tin oxide (ITO) is the transparent electrode of choice for organic light-emitting diodes (OLEDs). Replacing ITO for cost and performance reasons is a major drive across optoelectronics. In this work, we show that changing the transparent electrode on red, blue, and yellow OLEDs from ITO to a multilayer buffered aluminium zinc oxide/silver/aluminium zinc oxide (AZO/Ag/AZO) substantially enhances total output intensity, with better control of colour, its constancy, and intensity over the full exit hemisphere. The thin Ag containing layer induces a resonant cavity optical response of the complete device. This is tuned to the emission spectra of the emissivemore » material while minimizing internally trapped light. A complete set of spectral intensity data is presented across the full exit hemisphere for each electrode type and each OLED colour. Emission zone modelling of output spectra at a wide range of exit angles to the normal was in excellent agreement with the experimental data and hence could, in principle, be used to check and adjust production settings. These multilayer transparent electrodes show significant potential for both eliminating indium from OLEDs and spectrally shaping the emission.« less

Dimensional Analysis and Electric Potential Due to a Uniformly Charged Sheet

ERIC Educational Resources Information Center

Aghamohammadi, Amir

2011-01-01

Dimensional analysis, superposition principle, and continuity of electric potential are used to study the electric potential of a uniformly charged square sheet on its plane. It is shown that knowing the electric potential on the diagonal and inside the square sheet is equivalent to knowing it everywhere on the plane of the square sheet. The…

Do violations of the axioms of expected utility theory threaten decision analysis?

PubMed

Nease, R F

1996-01-01

Research demonstrates that people violate the independence principle of expected utility theory, raising the question of whether expected utility theory is normative for medical decision making. The author provides three arguments that violations of the independence principle are less problematic than they might first appear. First, the independence principle follows from other more fundamental axioms whose appeal may be more readily apparent than that of the independence principle. Second, the axioms need not be descriptive to be normative, and they need not be attractive to all decision makers for expected utility theory to be useful for some. Finally, by providing a metaphor of decision analysis as a conversation between the actual decision maker and a model decision maker, the author argues that expected utility theory need not be purely normative for decision analysis to be useful. In short, violations of the independence principle do not necessarily represent direct violations of the axioms of expected utility theory; behavioral violations of the axioms of expected utility theory do not necessarily imply that decision analysis is not normative; and full normativeness is not necessary for decision analysis to generate valuable insights.

Ensuring safety of implanted devices under MRI using reversed RF polarization.

PubMed

Overall, William R; Pauly, John M; Stang, Pascal P; Scott, Greig C

2010-09-01

Patients with long-wire medical implants are currently prevented from undergoing magnetic resonance imaging (MRI) scans due to the risk of radio frequency (RF) heating. We have developed a simple technique for determining the heating potential for these implants using reversed radio frequency (RF) polarization. This technique could be used on a patient-to-patient basis as a part of the standard prescan procedure to ensure that the subject's device does not pose a heating risk. By using reversed quadrature polarization, the MR scan can be sensitized exclusively to the potentially dangerous currents in the device. Here, we derive the physical principles governing the technique and explore the primary sources of inaccuracy. These principles are verified through finite-difference simulations and through phantom scans of implant leads. These studies demonstrate the potential of the technique for sensitively detecting potentially dangerous coupling conditions before they can do any harm. 2010 Wiley-Liss, Inc.

Revealing the optoelectronic and thermoelectric properties of the Zintl quaternary arsenides ACdGeAs{sub 2} (A = K, Rb)

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

Azam, Sikander; Khan, Saleem Ayaz; Goumri-Said, Souraya, E-mail: Souraya.Goumri-Said@chemistry.gatech.edu

Highlights: • Zintl tetragonal phase ACdGeAs{sub 2} (A = K, Rb) are chalcopyrite and semiconductors. • Their direct band gap is suitable for PV, optolectronic and thermoelectric applications. • Combination of DFT and Boltzmann transport theory is employed. • The present arsenides are found to be covalent materials. - Abstract: Chalcopyrite semiconductors have attracted much attention due to their potential implications in photovoltaic and thermoelectric applications. First principle calculations were performed to investigate the electronic, optical and thermoelectric properties of the Zintl tetragonal phase ACdGeAs{sub 2} (A = K, Rb) using the full potential linear augmented plane wave method andmore » the Engle–Vosko GGA (EV–GGA) approximation. The present compounds are found semiconductors with direct band gap and covalent bonding character. The optical transitions are investigated via the dielectric function (real and imaginary parts) along with other related optical constants including refractive index, reflectivity and energy-loss spectrum. Combining results from DFT and Boltzmann transport theory, we reported the thermoelectric properties such as the Seebeck’s coefficient, electrical and thermal conductivity, figure of merit and power factor as function of temperatures. The present chalcopyrite Zintl quaternary arsenides deserve to be explored for their potential applications as thermoelectric materials and for photovoltaic devices.« less

Production Principles and Technological Development of Novel Woven Spacer Preforms and Integrated Stiffener Structures

NASA Astrophysics Data System (ADS)

Torun, Ahmet R.; Mountasir, Adil; Hoffmann, Gerald; Cherif, Chokri

2013-06-01

3D textile preforms offer a high potential to increase mechanical properties of composites and/or decrease manufacturing costs. Within the scope of this study, production principles were developed for complex spacer preforms and integrated stiffeners. These principles were applied through technological further development of the well-known face-to-face and terry weaving techniques. Various woven preforms were produced with Glass fibre/Polypropylene (GF/PP) Commingled yarns, however, the technology is suitable for any type of reinforcement yarns. U-shaped woven spacer preform was consolidated into a sandwich composite component for lightweight applications.

Finding structure in the dark: Coupled dark energy, weak lensing, and the mildly nonlinear regime

NASA Astrophysics Data System (ADS)

Miranda, Vinicius; González, Mariana Carrillo; Krause, Elisabeth; Trodden, Mark

2018-03-01

We reexamine interactions between the dark sectors of cosmology, with a focus on robust constraints that can be obtained using only mildly nonlinear scales. While it is well known that couplings between dark matter and dark energy can be constrained to the percent level when including the full range of scales probed by future optical surveys, calibrating matter power spectrum emulators to all possible choices of potentials and couplings requires many computationally expensive n-body simulations. Here we show that lensing and clustering of galaxies in combination with the cosmic microwave background (CMB) are capable of probing the dark sector coupling to the few percent level for a given class of models, using only linear and quasilinear Fourier modes. These scales can, in principle, be described by semianalytical techniques such as the effective field theory of large-scale structure.

Variational Calculations of Ro-Vibrational Energy Levels and Transition Intensities for Tetratomic Molecules

NASA Technical Reports Server (NTRS)

Schwenke, David W.; Langhoff, Stephen R. (Technical Monitor)

1995-01-01

A description is given of an algorithm for computing ro-vibrational energy levels for tetratomic molecules. The expressions required for evaluating transition intensities are also given. The variational principle is used to determine the energy levels and the kinetic energy operator is simple and evaluated exactly. The computational procedure is split up into the determination of one dimensional radial basis functions, the computation of a contracted rotational-bending basis, followed by a final variational step coupling all degrees of freedom. An angular basis is proposed whereby the rotational-bending contraction takes place in three steps. Angular matrix elements of the potential are evaluated by expansion in terms of a suitable basis and the angular integrals are given in a factorized form which simplifies their evaluation. The basis functions in the final variational step have the full permutation symmetries of the identical particles. Sample results are given for HCCH and BH3.

Engineering radical polymer electrodes for electrochemical energy storage

NASA Astrophysics Data System (ADS)

Nevers, Douglas R.; Brushett, Fikile R.; Wheeler, Dean R.

2017-06-01

In principle a wide range of organic materials can store energy in the form of reversible redox conversions of stable radicals. Such chemistry holds great promise for energy storage applications due to high theoretical capacities, high rate capabilities, intrinsic structural tunability, and the possibility of low-cost "green" syntheses from renewable sources. There have been steady improvements in the design of organic radical polymers, in which radicals are incorporated into the backbone and/or as pendant groups. This review highlights opportunities for improved redox molecule and polymer design along with the key challenges (e.g., transport phenomena, solubility, and reaction mechanisms) to transitioning known organic radicals into high-performance electrodes. Ultimately, organic-based batteries are still a nascent field with many open questions. Further advances in molecular design, electrode engineering, and device architecture will be required for these systems to reach their full potential and meet the diverse and increasing demands for energy storage.

The utility of ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) for clinically relevant steroid analysis.

PubMed

Storbeck, Karl-Heinz; Gilligan, Lorna; Jenkinson, Carl; Baranowski, Elizabeth S; Quanson, Jonathan L; Arlt, Wiebke; Taylor, Angela E

2018-05-15

Liquid chromatography tandem mass spectrometry (LC-MS/MS) assays are considered the reference standard for serum steroid hormone analyses, while full urinary steroid profiles are only achievable by gas chromatography (GC-MS). Both LC-MS/MS and GC-MS have well documented strengths and limitations. Recently, commercial ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) systems have been developed. These systems combine the resolution of GC with the high-throughput capabilities of UHPLC. Uptake of this new technology into research and clinical labs has been slow, possibly due to the perceived increase in complexity. Here we therefore present fundamental principles of UHPSFC-MS/MS and the likely applications for this technology in the clinical research setting, while commenting on potential hurdles based on our experience to date. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

3D printing of robotic soft actuators with programmable bioinspired architectures.

PubMed

Schaffner, Manuel; Faber, Jakob A; Pianegonda, Lucas; Rühs, Patrick A; Coulter, Fergal; Studart, André R

2018-02-28

Soft actuation allows robots to interact safely with humans, other machines, and their surroundings. Full exploitation of the potential of soft actuators has, however, been hindered by the lack of simple manufacturing routes to generate multimaterial parts with intricate shapes and architectures. Here, we report a 3D printing platform for the seamless digital fabrication of pneumatic silicone actuators exhibiting programmable bioinspired architectures and motions. The actuators comprise an elastomeric body whose surface is decorated with reinforcing stripes at a well-defined lead angle. Similar to the fibrous architectures found in muscular hydrostats, the lead angle can be altered to achieve elongation, contraction, or twisting motions. Using a quantitative model based on lamination theory, we establish design principles for the digital fabrication of silicone-based soft actuators whose functional response is programmed within the material's properties and architecture. Exploring such programmability enables 3D printing of a broad range of soft morphing structures.

Thermionic cooling devices based on resonant-tunneling AlGaAs/GaAs heterostructure

NASA Astrophysics Data System (ADS)

Bescond, M.; Logoteta, D.; Michelini, F.; Cavassilas, N.; Yan, T.; Yangui, A.; Lannoo, M.; Hirakawa, K.

2018-02-01

We study by means of full quantum simulations the operating principle and performance of a semiconductor heterostructure refrigerator combining resonant tunneling filtering and thermionic emission. Our model takes into account the coupling between the electric and thermal currents by self-consistently solving the transport equations within the non-equilibrium Green’s function framework and the heat equation. We show that the device can achieve relatively high cooling power values, while in the considered implementation, the maximum lattice temperature drop is severely limited by the thermal conductivity of the constituting materials. In such an out-of-equilibrium structure, we then emphasize the significant deviation of the phonon temperature from its electronic counterpart which can vary over several hundred Kelvin. The interplay between those two temperatures and the impact on the electrochemical potential is also discussed. Finally, viable options toward an optimization of the device are proposed.

MR-guided prostate interventions.

PubMed

Tempany, Clare; Straus, Sarah; Hata, Nobuhiko; Haker, Steven

2008-02-01

In this article the current issues of diagnosis and detection of prostate cancer are reviewed. The limitations for current techniques are highlighted and some possible solutions with MR imaging and MR-guided biopsy approaches are reviewed. There are several different biopsy approaches under investigation. These include transperineal open magnet approaches to closed-bore 1.5T transrectal biopsies. The imaging, image processing, and tracking methods are also discussed. In the arena of therapy, MR guidance has been used in conjunction with radiation methods, either brachytherapy or external delivery. The principles of the radiation treatment, the toxicities, and use of images are outlined. The future role of imaging and image-guided interventions lie with providing a noninvasive surrogate for cancer surveillance or monitoring treatment response. The shift to minimally invasive focal therapies has already begun and will be very exciting when MR-guided focused ultrasound surgery reaches its full potential. (Copyright) 2008 Wiley-Liss, Inc.

MR-Guided Prostate Interventions

PubMed Central

Tempany, Clare; Straus, Sarah; Hata, Nobuhiko; Haker, Steven

2009-01-01

In this article the current issues of diagnosis and detection of prostate cancer are reviewed. The limitations for current techniques are highlighted and some possible solutions with MR imaging and MR-guided biopsy approaches are reviewed. There are several different biopsy approaches under investigation. These include transperineal open magnet approaches to closed-bore 1.5T transrectal biopsies. The imaging, image processing, and tracking methods are also discussed. In the arena of therapy, MR guidance has been used in conjunction with radiation methods, either brachytherapy or external delivery. The principles of the radiation treatment, the toxicities, and use of images are outlined. The future role of imaging and image-guided interventions lie with providing a noninvasive surrogate for cancer surveillance or monitoring treatment response. The shift to minimally invasive focal therapies has already begun and will be very exciting when MR-guided focused ultrasound surgery reaches its full potential. PMID:18219689

Quantum Secure Direct Communication with Quantum Memory

NASA Astrophysics Data System (ADS)

Zhang, Wei; Ding, Dong-Sheng; Sheng, Yu-Bo; Zhou, Lan; Shi, Bao-Sen; Guo, Guang-Can

2017-06-01

Quantum communication provides an absolute security advantage, and it has been widely developed over the past 30 years. As an important branch of quantum communication, quantum secure direct communication (QSDC) promotes high security and instantaneousness in communication through directly transmitting messages over a quantum channel. The full implementation of a quantum protocol always requires the ability to control the transfer of a message effectively in the time domain; thus, it is essential to combine QSDC with quantum memory to accomplish the communication task. In this Letter, we report the experimental demonstration of QSDC with state-of-the-art atomic quantum memory for the first time in principle. We use the polarization degrees of freedom of photons as the information carrier, and the fidelity of entanglement decoding is verified as approximately 90%. Our work completes a fundamental step toward practical QSDC and demonstrates a potential application for long-distance quantum communication in a quantum network.

Quantum Secure Direct Communication with Quantum Memory.

PubMed

Zhang, Wei; Ding, Dong-Sheng; Sheng, Yu-Bo; Zhou, Lan; Shi, Bao-Sen; Guo, Guang-Can

2017-06-02

Quantum communication provides an absolute security advantage, and it has been widely developed over the past 30 years. As an important branch of quantum communication, quantum secure direct communication (QSDC) promotes high security and instantaneousness in communication through directly transmitting messages over a quantum channel. The full implementation of a quantum protocol always requires the ability to control the transfer of a message effectively in the time domain; thus, it is essential to combine QSDC with quantum memory to accomplish the communication task. In this Letter, we report the experimental demonstration of QSDC with state-of-the-art atomic quantum memory for the first time in principle. We use the polarization degrees of freedom of photons as the information carrier, and the fidelity of entanglement decoding is verified as approximately 90%. Our work completes a fundamental step toward practical QSDC and demonstrates a potential application for long-distance quantum communication in a quantum network.

Thermionic cooling devices based on resonant-tunneling AlGaAs/GaAs heterostructure.

PubMed

Bescond, M; Logoteta, D; Michelini, F; Cavassilas, N; Yan, T; Yangui, A; Lannoo, M; Hirakawa, K

2018-02-14

We study by means of full quantum simulations the operating principle and performance of a semiconductor heterostructure refrigerator combining resonant tunneling filtering and thermionic emission. Our model takes into account the coupling between the electric and thermal currents by self-consistently solving the transport equations within the non-equilibrium Green's function framework and the heat equation. We show that the device can achieve relatively high cooling power values, while in the considered implementation, the maximum lattice temperature drop is severely limited by the thermal conductivity of the constituting materials. In such an out-of-equilibrium structure, we then emphasize the significant deviation of the phonon temperature from its electronic counterpart which can vary over several hundred Kelvin. The interplay between those two temperatures and the impact on the electrochemical potential is also discussed. Finally, viable options toward an optimization of the device are proposed.

Electron-positron momentum density in Tl 2Ba 2CuO 6

NASA Astrophysics Data System (ADS)

Barbiellini, B.; Gauthier, M.; Hoffmann, L.; Jarlborg, T.; Manuel, A. A.; Massidda, S.; Peter, M.; Triscone, G.

1994-08-01

We present calculations of the electron-positron momentum density for the high- Tc superconductor Tl 2Ba 2CuO 6, together with some preliminary two-dimensional angular correlation of the annihilation radiation (2D-ACAR) measurements. The calculations are based on the first-principles electronic structure obtained using the full-potential linearized augmented plane wave (FLAPW) and the linear muffin-tin orbital (LMTO) methods. We also use a linear combination of the atomic orbitals-molecular orbital method (LCAO-MO) to discuss orbital contributions to the anisotropies. Some agreement between calculated and measured 2D-ACAR anisotropies encourage sample improvement for further Fermi surface investigations. Indeed, our results indicate a non-negligle overlap of the positron wave function with the CuOo 2 plane electrons. Therefore, this compound may be well suited for investigating the relevant CuO 2 Fermi surface by 2D-ACAR.

Ab initio study on structural stability of uranium carbide

NASA Astrophysics Data System (ADS)

Sahoo, B. D.; Joshi, K. D.; Gupta, Satish C.

2013-06-01

First principles calculations have been performed using plane wave pseudopotential and full potential linearized augmented plane wave (FP-LAPW) methods to analyze structural, elastic and dynamic stability of UC under hydrostatic compression. Our calculations within pseudopotential method suggest that the rocksalt (B1) structure will transform to body centered orthorhombic (bco) structure at ˜21.5 GPa. The FP-LAPW calculations put this transition at 23 GPa. The transition pressures determined from our calculations though agree reasonably with the experimental value of 27 GPa, the high pressure bco structure suggested by theory differs slightly from the experimentally reported pseudo bco phase. The elastic stability analysis of B1 phase suggests that the B1 to bco transition is driven by the failure of C44 modulus. This finding is further substantiated by the lattice dynamic calculations which demonstrate that the B1 phase becomes dynamically unstable around the transition pressure and the instability is of long wavelength nature.

Polio Endgame: Lessons Learned From the Immunization Systems Management Group.

PubMed

Zipursky, Simona; Vandelaer, Jos; Brooks, Alan; Dietz, Vance; Kachra, Tasleem; Farrell, Margaret; Ottosen, Ann; Sever, John L; Zaffran, Michel J

2017-07-01

The Immunization Systems Management Group (IMG) was established to coordinate and oversee objective 2 of the Polio Eradication and Endgame Strategic Plan 2013-2018, namely, (1) introduction of ≥1 dose of inactivated poliovirus vaccine in all 126 countries using oral poliovirus vaccine (OPV) only as of 2012, (2) full withdrawal of OPV, starting with the withdrawal of its type 2 component, and (3) using polio assets to strengthen immunization systems in 10 priority countries. The IMG's inclusive, transparent, and partnership-focused approach proved an effective means of leveraging the comparative and complementary strengths of each IMG member agency. This article outlines 10 key factors behind the IMG's success, providing a potential set of guiding principles for the establishment and implementation of other interagency collaborations and initiatives beyond the polio sphere. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Framework for the design and delivery of organized physical activity sessions for children and adolescents: rationale and description of the 'SAAFE' teaching principles.

PubMed

Lubans, David R; Lonsdale, Chris; Cohen, Kristen; Eather, Narelle; Beauchamp, Mark R; Morgan, Philip J; Sylvester, Benjamin D; Smith, Jordan J

2017-02-23

The economic burden of inactivity is substantial, with conservative estimates suggesting the global cost to health care systems is more than US$50 billion. School-based programs, including physical education and school sport, have been recommended as important components of a multi-sector, multi-system approach to address physical inactivity. Additionally, community sporting clubs and after-school programs (ASPs) offer further opportunities for young people to be physically active outside of school. Despite demonstrating promise, current evidence suggests school-based physical activity programs, community sporting clubs and ASPs are not achieving their full potential. For example, physical activity levels in physical education (PE) and ASP sessions are typically much lower than recommended. For these sessions to have the strongest effects on young people's physical activity levels and their on-going physical literacy, they need to improve in quality and should be highly active and engaging. This paper presents the Supportive, Active, Autonomous, Fair, Enjoyable (SAAFE) principles, which represent an evidence-based framework designed to guide the planning, delivery and evaluation of organized physical activity sessions in school, community sport and ASPs. In this paper we provide a narrative and integrative review of the conceptual and empirical bases that underpin this framework and highlight implications for knowledge translation and application.

Molecular dynamics simulations for mechanical properties of borophene: parameterization of valence force field model and Stillinger-Weber potential

PubMed Central

Zhou, Yu-Ping; Jiang, Jin-Wu

2017-01-01

While most existing theoretical studies on the borophene are based on first-principles calculations, the present work presents molecular dynamics simulations for the lattice dynamical and mechanical properties in borophene. The obtained mechanical quantities are in good agreement with previous first-principles calculations. The key ingredients for these molecular dynamics simulations are the two efficient empirical potentials developed in the present work for the interaction of borophene with low-energy triangular structure. The first one is the valence force field model, which is developed with the assistance of the phonon dispersion of borophene. The valence force field model is a linear potential, so it is rather efficient for the calculation of linear quantities in borophene. The second one is the Stillinger-Weber potential, whose parameters are derived based on the valence force field model. The Stillinger-Weber potential is applicable in molecular dynamics simulations of nonlinear physical or mechanical quantities in borophene. PMID:28349983

Conducting polymer actuators: From basic concepts to proprioceptive systems

NASA Astrophysics Data System (ADS)

Martinez Gil, Jose Gabriel

Designers and engineers have been dreaming for decades of motors sensing, by themselves, working and surrounding conditions, as biological muscles do originating proprioception. Here bilayer full polymeric artificial muscles were checked up to very high cathodic potential limits (-2.5 V) in aqueous solution by cyclic voltammetry. The electrochemical driven exchange of ions from the conducting polymer film, and the concomitant Faradaic bending movement of the muscle, takes place in the full studied potential range. The presence of trapped counterion after deep reduction was corroborated by EDX determinations giving quite high electronic conductivity to the device. The large bending movement was used as a tool to quantify the amount of water exchanged per reaction unit (exchanged electron or ion). The potential evolutions of self-supported films of conducting polymers or conducting polymers (polypyrrole, polyaniline) coating different microfibers, during its oxidation/reduction senses working mechanical, thermal, chemical or electrical variables. The evolution of the muscle potential from electrochemical artificial muscles based on electroactive materials such as intrinsically conducting polymers and driven by constant currents senses, while working, any variation of the mechanical (trailed mass, obstacles, pressure, strain or stress), thermal or chemical conditions of work. One physically uniform artificial muscle includes one electrochemical motor and several sensors working simultaneously under the same driving reaction. Actuating (current and charge) and sensing (potential and energy) magnitudes are present, simultaneously, in the only two connecting wires and can be read by the computer at any time. From basic polymeric, mechanical and electrochemical principles a physicochemical equation describing artificial proprioception has been developed. It includes and describes, simultaneously, the evolution of the muscle potential during actuation as a function of the motor characteristics (rate and sense of the movement, relative position, and required energy) and the working variables (temperature, electrolyte concentration, mechanical conditions and driving current). By changing working conditions experimental results overlap theoretical predictions. The ensemble computer-generator-muscle-theoretical equation constitutes and describes artificial mechanical, thermal and chemical proprioception of the system. Proprioceptive tools and most intelligent zoomorphic or anthropomorphic soft robots can be envisaged.

Defending the social value of knowledge as a safeguard for public trust.

PubMed

Holzer, Felicitas S

2017-09-01

The 'socially valuable knowledge' (SVK) principle has been widely acknowledged as one of the most important guiding principles for biomedical research involving human subjects. The principle states that the potential of producing socially valuable knowledge is a necessary requirement, although not sufficient, for the ethical conduct of research projects. This is due to the assumption that the social value of knowledge avoids exploitation of research subjects and justifies the use of health resources. However, more recently, several authors have started interrogating the validity of SVK in research and offered various lines of argument against the SVK principle as a necessary constraint to research. In this article, I will reconstruct the main arguments of this discussion between defenders and debunkers of the SVK principle and offer a third way to consider the social value of knowledge in research studies. I will argue that the social value of knowledge can be supported by an independent justification. This justification of the SVK principle addresses the rationality and common interest of researchers. Thus, I will introduce the SVK principle as a safeguarding principle for public trust based on a conceptual framework by Alex John London. My approach justifies keeping the principle as a precautionary and rational requirement for human health research that all rational stakeholders can agree upon. © 2017 John Wiley & Sons Ltd.

Tuning topological phases in the XMnSb2 system via chemical substitution from first principles

NASA Astrophysics Data System (ADS)

Griffin, Sinead M.; Neaton, Jeffrey B.

New Dirac materials are sought for their interesting fundamental physics and for their potential technological applications. Protected symmetries offer a route to potential zero mass Dirac and Weyl fermions, and can lead unique transport properties and spectroscopic signatures. In this work, we use first-principles calculations to study the XMnSb2 family of materials and show how varying X changes the nature of bulk protected topological features in their electronic structure. We further discuss new design rules for predicting new topological materials suggested by our calculations. SG is supported by the Early Postdoc Mobility Fellowship of the SNF.

A biologist's view of the relevance of thermodynamics and physical chemistry to cryobiology✰

PubMed Central

Mazur, Peter

2013-01-01

Thermodynamics and physical chemistry have played powerful roles the past forty-five years in interpreting cryobiological problems and in predicting cryobiological outcomes. The author has been guided by a few core principles in using these concepts and tools and this paper discusses these core principles. They are (1) the importance of chemical potentials and of the difference between the chemical potentials of water and solutes inside the cell and outside in determining the direction and rate of fluxes of water and solutes. (2) The influence of the curvature of an ice crystal on its chemical potential and on the ability of ice to pass through pores in cell membranes, on the nucleation temperature of supercooled water, and on the recrystallization of ice. (3) The use of Le Chatalier's Principle in qualitatively predicting the direction of a reaction is response to variables like pressure. (4) The fact that the energy differences between State A and State B are independent of the path taken to go from A to B. (5) The importance of being aware of the assumptions underlying thermodynamic models of cryobiological events. And (6), the difficulties in obtaining experimental verification of thermodynamic and physical-chemical models. PMID:19962974

Statistical analogues of thermodynamic extremum principles

NASA Astrophysics Data System (ADS)

Ramshaw, John D.

2018-05-01

As shown by Jaynes, the canonical and grand canonical probability distributions of equilibrium statistical mechanics can be simply derived from the principle of maximum entropy, in which the statistical entropy S=- {k}{{B}}{\\sum }i{p}i{log}{p}i is maximised subject to constraints on the mean values of the energy E and/or number of particles N in a system of fixed volume V. The Lagrange multipliers associated with those constraints are then found to be simply related to the temperature T and chemical potential μ. Here we show that the constrained maximisation of S is equivalent to, and can therefore be replaced by, the essentially unconstrained minimisation of the obvious statistical analogues of the Helmholtz free energy F = E ‑ TS and the grand potential J = F ‑ μN. Those minimisations are more easily performed than the maximisation of S because they formally eliminate the constraints on the mean values of E and N and their associated Lagrange multipliers. This procedure significantly simplifies the derivation of the canonical and grand canonical probability distributions, and shows that the well known extremum principles for the various thermodynamic potentials possess natural statistical analogues which are equivalent to the constrained maximisation of S.

The patient-centered medical home: an ethical analysis of principles and practice.

PubMed

Braddock, Clarence H; Snyder, Lois; Neubauer, Richard L; Fischer, Gary S

2013-01-01

The patient-centered medical home (PCMH), with its focus on patient-centered care, holds promise as a way to reinvigorate the primary care of patients and as a necessary component of health care reform. While its tenets have been the subject of review, the ethical dimensions of the PCMH have not been fully explored. Consideration of the ethical foundations for the core principles of the PCMH can and should be part of the debate concerning its merits. The PCMH can align with the principles of medical ethics and potentially strengthen the patient-physician relationship and aspects of health care that patients value. Patient choice and these ethical considerations are central and at least as important as the economic and practical arguments in support of the PCMH, if not more so. Further, the ethical principles that support key concepts of the PCMH have implications for the design and implementation of the PCMH. This paper explores the PCMH in light of core principles of ethics and professionalism, with an emphasis both on how the concept of the PCMH may reinforce core ethical principles of medical practice and on further implications of these principles.

Toward Formulating Evidence-Based Principles of LGB-Affirmative Psychotherapy

PubMed Central

Proujansky, Rachel A.; Pachankis, John E.

2015-01-01

In this commentary, we review eight potential LGB-affirmative psychotherapy principles for improving minority stress coping among sexual minority clients. We illustrate these principles with examples from both Mandel’s (2014) treatment approach and our clinical research team’s recent attempt to create and test the efficacy of a treatment employing these principles in an ongoing randomized controlled trial. These principles are grounded in empirical research regarding the mechanisms through which minority stress compromises the mental health of sexual minority individuals and are supported by clinical expert consensus. The specific principles that we review include: 1) normalizing the mental health impact of minority stress, 2) facilitating emotion awareness, regulation, and acceptance, 3) decreasing avoidance, 4) restructuring minority stress cognitions, 5) empowering sexual minority clients to communicate assertively, 6) validating sexual minority individuals’ unique strengths, 7) building supportive relationships, and 8) affirming healthy, rewarding expressions of sexuality. We believe that Mandel’s skillful approach to helping her hybrid client Adam cope with minority stressors, such as internalized homophobia, and associated mental health problems such as substance abuse and depression, to form a healthy identity as a gay man represents an exemplary demonstration of these principles in action. PMID:26617475

SOMATOSENSORY EVOKED POTENTIALS

EPA Science Inventory

Somatosensory evoked potentials (SEPs) have been used by neuroscientists for many years. The versatility of the method is attested to be the differing purposes to which it has been applied. Initially, SEPs were used to uncover basic principles of sensory processing. A casual glan...

Mass-stiffness substructuring of an elastic metasurface for full transmission beam steering

NASA Astrophysics Data System (ADS)

Lee, Hyuk; Lee, Jun Kyu; Seung, Hong Min; Kim, Yoon Young

2018-03-01

The metasurface concept has a significant potential due to its novel wavefront-shaping functionalities that can be critically useful for ultrasonic and solid wave-based applications. To achieve the desired functionalities, elastic metasurfaces should cover full 2π phase shift and also acquire full transmission within subwavelength scale. However, they have not been explored much with respect to the elastic regime, because the intrinsic proportionality of mass-stiffness within the continuum elastic media causes an inevitable trade-off between abrupt phase shift and sufficient transmission. Our goal is to engineer an elastic metasurface that can realize an inverse relation between (amplified) effective mass and (weakened) stiffness in order to satisfy full 2π phase shift as well as full transmission. To achieve this goal, we propose a continuum elastic metasurface unit cell that is decomposed into two substructures, namely a mass-tuning substructure with a local dipolar resonator and a stiffness-tuning substructure composed of non-resonant multiply-perforated slits. We demonstrate analytically, numerically, and experimentally that this unique substructured unit cell can satisfy the required phase shift with high transmission. The substructuring enables independent tuning of the elastic properties over a wide range of values. We use a mass-spring model of the proposed continuum unit cell to investigate the working mechanism of the proposed metasurface. With the designed metasurface consisting of substructured unit cells embedded in an aluminum plate, we demonstrate that our metasurface can successfully realize anomalous steering and focusing of in-plane longitudinal ultrasonic beams. The proposed substructuring concept is expected to provide a new principle for the design of general elastic metasurfaces that can be used to efficiently engineer arbitrary wave profiles.

A review on the systematic formulation of 3-D multiparameter full waveform inversion in viscoelastic medium

NASA Astrophysics Data System (ADS)

Yang, Pengliang; Brossier, Romain; Métivier, Ludovic; Virieux, Jean

2016-10-01

In this paper, we study 3-D multiparameter full waveform inversion (FWI) in viscoelastic media based on the generalized Maxwell/Zener body including arbitrary number of attenuation mechanisms. We present a frequency-domain energy analysis to establish the stability condition of a full anisotropic viscoelastic system, according to zero-valued boundary condition and the elastic-viscoelastic correspondence principle: the real-valued stiffness matrix becomes a complex-valued one in Fourier domain when seismic attenuation is taken into account. We develop a least-squares optimization approach to linearly relate the quality factor with the anelastic coefficients by estimating a set of constants which are independent of the spatial coordinates, which supplies an explicit incorporation of the parameter Q in the general viscoelastic wave equation. By introducing the Lagrangian multipliers into the matrix expression of the wave equation with implicit time integration, we build a systematic formulation of multiparameter FWI for full anisotropic viscoelastic wave equation, while the equivalent form of the state and adjoint equation with explicit time integration is available to be resolved efficiently. In particular, this formulation lays the foundation for the inversion of the parameter Q in the time domain with full anisotropic viscoelastic properties. In the 3-D isotropic viscoelastic settings, the anelastic coefficients and the quality factors using bulk and shear moduli parametrization can be related to the counterparts using P and S velocity. Gradients with respect to any other parameter of interest can be found by chain rule. Pioneering numerical validations as well as the real applications of this most generic framework will be carried out to disclose the potential of viscoelastic FWI when adequate high-performance computing resources and the field data are available.

Reframing conceptual physics: Improving relevance to elementary education and sonography majors

NASA Astrophysics Data System (ADS)

LaFazia, David Gregory

This study outlines the steps taken to reframe the Waves and Periodicity unit within a conceptual physics course. Beyond this unit reframing process, this paper explores the activities that made up the reframed unit and how each was developed and revised. The unit was reframed to improve relevance of the activities to the Elementary Education and Diagnostic Medical Sonography majors who make up the bulk of the course roster. The unit was reframed around ten design principles that were built on best practices from the literature, survey responses, and focused interviews. These principles support the selection of a biology-integrated themed approach to teaching physics. This is done through active and highly kinesthetic learning across three realms of human experience: physical, social, and cognitive. The unit materials were designed around making connections to students' future careers while requiring students to take progressively more responsibility in activities and assessments. Several support strategies are employed across these activities and assessments, including an energy-first, guided-inquiry approach to concept scaffolding and accommodations for diverse learners. Survey responses were solicited from physics instructors experienced with this population, Elementary Education and Sonography program advisors, and curriculum design, learning strategies, and educational technology experts. The reframed unit was reviewed by doctoral-level science education experts and revised to further improve the depth and transparency with which the design principles reframe the unit activities. The reframed unit contains a full unit plan, lesson plans, and full unit materials. These include classroom and online activities, assessments, and templates for future unit and lesson planning. Additional supplemental materials are provided to support Elementary Education and Sonography students and program advisors and also further promote the reframed unit materials and design principles. The unit is designed to be educative in nature and serves as a model for the reframing of other units. A number of the design principles are highly transdisciplinary in nature and may be applied for reframing instructional units outside of the physics and science disciplines.

Applying Human Factors Principles to Mitigate Usability Issues Related to Embedded Assumptions in Health Information Technology Design

PubMed Central

Lowry, Svetlana Z; Patterson, Emily S

2014-01-01

Background There is growing recognition that design flaws in health information technology (HIT) lead to increased cognitive work, impact workflows, and produce other undesirable user experiences that contribute to usability issues and, in some cases, patient harm. These usability issues may in turn contribute to HIT utilization disparities and patient safety concerns, particularly among “non-typical” HIT users and their health care providers. Health care disparities are associated with poor health outcomes, premature death, and increased health care costs. HIT has the potential to reduce these disparate outcomes. In the computer science field, it has long been recognized that embedded cultural assumptions can reduce the usability, usefulness, and safety of HIT systems for populations whose characteristics differ from “stereotypical” users. Among these non-typical users, inappropriate embedded design assumptions may contribute to health care disparities. It is unclear how to address potentially inappropriate embedded HIT design assumptions once detected. Objective The objective of this paper is to explain HIT universal design principles derived from the human factors engineering literature that can help to overcome potential usability and/or patient safety issues that are associated with unrecognized, embedded assumptions about cultural groups when designing HIT systems. Methods Existing best practices, guidance, and standards in software usability and accessibility were subjected to a 5-step expert review process to identify and summarize those best practices, guidance, and standards that could help identify and/or address embedded design assumptions in HIT that could negatively impact patient safety, particularly for non-majority HIT user populations. An iterative consensus-based process was then used to derive evidence-based design principles from the data to address potentially inappropriate embedded cultural assumptions. Results Design principles that may help identify and address embedded HIT design assumptions are available in the existing literature. Conclusions Evidence-based HIT design principles derived from existing human factors and informatics literature can help HIT developers identify and address embedded cultural assumptions that may underlie HIT-associated usability and patient safety concerns as well as health care disparities. PMID:27025349

Applying Human Factors Principles to Mitigate Usability Issues Related to Embedded Assumptions in Health Information Technology Design.

PubMed

Gibbons, Michael C; Lowry, Svetlana Z; Patterson, Emily S

2014-12-18

There is growing recognition that design flaws in health information technology (HIT) lead to increased cognitive work, impact workflows, and produce other undesirable user experiences that contribute to usability issues and, in some cases, patient harm. These usability issues may in turn contribute to HIT utilization disparities and patient safety concerns, particularly among "non-typical" HIT users and their health care providers. Health care disparities are associated with poor health outcomes, premature death, and increased health care costs. HIT has the potential to reduce these disparate outcomes. In the computer science field, it has long been recognized that embedded cultural assumptions can reduce the usability, usefulness, and safety of HIT systems for populations whose characteristics differ from "stereotypical" users. Among these non-typical users, inappropriate embedded design assumptions may contribute to health care disparities. It is unclear how to address potentially inappropriate embedded HIT design assumptions once detected. The objective of this paper is to explain HIT universal design principles derived from the human factors engineering literature that can help to overcome potential usability and/or patient safety issues that are associated with unrecognized, embedded assumptions about cultural groups when designing HIT systems. Existing best practices, guidance, and standards in software usability and accessibility were subjected to a 5-step expert review process to identify and summarize those best practices, guidance, and standards that could help identify and/or address embedded design assumptions in HIT that could negatively impact patient safety, particularly for non-majority HIT user populations. An iterative consensus-based process was then used to derive evidence-based design principles from the data to address potentially inappropriate embedded cultural assumptions. Design principles that may help identify and address embedded HIT design assumptions are available in the existing literature. Evidence-based HIT design principles derived from existing human factors and informatics literature can help HIT developers identify and address embedded cultural assumptions that may underlie HIT-associated usability and patient safety concerns as well as health care disparities.

Principles of time evolution in classical physics

NASA Astrophysics Data System (ADS)

Güémez, J.; Fiolhais, M.

2018-07-01

We address principles of time evolution in classical mechanical/thermodynamical systems in translational and rotational motion, in three cases: when there is conservation of mechanical energy, when there is energy dissipation and when there is mechanical energy production. In the first case, the time derivative of the Hamiltonian vanishes. In the second one, when dissipative forces are present, the time evolution is governed by the minimum potential energy principle, or, equivalently, maximum increase of the entropy of the universe. Finally, in the third situation, when internal sources of work are available to the system, it evolves in time according to the principle of minimum Gibbs function. We apply the Lagrangian formulation to the systems, dealing with the non-conservative forces using restriction functions such as the Rayleigh dissipative function.

Defense Standardization Program Journal. October/December 2012

DTIC Science & Technology

2012-10-01

Barriers to Trade ( TBT ).The WTO TBT agreement establishes principles for interna- tional standardization processes using attributes similar to those...WTO TBT agreement, the proposed standardization regulation states that public authorities should make best use of the full range of relevant

Sponsored Programs.

ERIC Educational Resources Information Center

College and University Business Administration, 1980

1980-01-01

General administrative principles and procedures applicable to any type of program sponsored by external funds, including the federal government, are examined. Contracts, grants, and cooperative agreements are the devices for authorizing sponsored programs. Since the institutions assume full legal responsibility for the programs and for fulfilling…

Effectiveness of alcohol prevention interventions based on the principles of social marketing: a systematic review

PubMed Central

2013-01-01

Background Alcohol education aims to increase knowledge on the harm related to alcohol, and to change attitudes and drinking behaviour. However, little (lasting) evidence has been found for alcohol education, in changing alcohol-related attitudes and behaviour. Social marketing uses marketing techniques to achieve a social or healthy goal, and can be used in alcohol education. Social marketing consists of eight principles: customer orientation, insight, segmentation, behavioural goals, exchange, competition, methods mix, and is theory based. This review investigates the application of social marketing in alcohol prevention interventions, and whether application of social marketing influences alcohol-related attitudes or behaviour. Method A literature search was conducted in PubMed, PsychInfo, Cochrane and Scopus. Inclusion criteria were that original papers had to describe the effects of an alcohol prevention intervention developed according to one or more principles of social marketing. No limits were set on the age of the participants or on the kind of alcohol prevention intervention. The abstracts of the 274 retrieved studies were reviewed and the full texts of potentially relevant studies were screened. Results Six studies met the inclusion criteria and were included in this review. These six studies showed associations for the application of social marketing techniques on alcohol-related attitudes or behaviour; one study relates to participation in a drinking event, four to alcohol drinking behaviour, two to driving a car while under the influence of alcohol, two to recognition of campaign messages or campaign logo, and one to awareness of the campaign. However, no associations were also found. In addition, the studies had several limitations related to a control group, response rate and study methodology. Conclusion Based on this review, the effect of applying the principles of social marketing in alcohol prevention in changing alcohol-related attitudes or behaviour could not be assessed. More research, with a good quality methodology, like using a randomized control trial and measuring short, medium, and long-term effects, is required on this topic. Policy implications are discussed. PMID:23725406

Screening Health Risk Assessment Burn Pit Exposures, Balad Air Base, Iraq and Addendum Report

DTIC Science & Technology

2008-05-01

risk uses principles drawn from many scientific disciplines including chemistry , toxicology, physics, mathematics, and statistics. Because the data...uses principles drawn from many scientific disciplines, including chemistry , toxicology, physics, mathematics, and statistics. Because the data...natural chemicals in plants (called flavonoids ) also act on the Ah-receptor and could potentially block the effects of dioxins. One more reason to

A Prototype Graphical User Interface for Co-op: A Group Decision Support System.

DTIC Science & Technology

1992-03-01

achieve their potential to communicate. Information-oriented, systematic graphic design is the use of typography , symbols, color, and other static and...apphcuittin by reducig Uber ellurt anid enhuncizig Iliteracti. ’Iliis thesis designs and de% elupht Itrututylle Graphical User Interface iGUl i fui Cu f...ORGANIZATION.... .. .. ............ II. INTERFACE DESIGN PRINCIPLES. .............. 7 A. GRAPHICAL USER INTERFACES.............7 1. Design Principles

A Variational Principle for Reconstruction of Elastic Deformations in Shear Deformable Plates and Shells

NASA Technical Reports Server (NTRS)

Tessler, Alexander; Spangler, Jan L.

2003-01-01

A variational principle is formulated for the inverse problem of full-field reconstruction of three-dimensional plate/shell deformations from experimentally measured surface strains. The formulation is based upon the minimization of a least squares functional that uses the complete set of strain measures consistent with linear, first-order shear-deformation theory. The formulation, which accommodates for transverse shear deformation, is applicable for the analysis of thin and moderately thick plate and shell structures. The main benefit of the variational principle is that it is well suited for C(sup 0)-continuous displacement finite element discretizations, thus enabling the development of robust algorithms for application to complex civil and aeronautical structures. The methodology is especially aimed at the next generation of aerospace vehicles for use in real-time structural health monitoring systems.

Extended Producer Responsibility and Product Stewardship for Tobacco Product Waste

PubMed Central

Curtis, Clifton; Collins, Susan; Cunningham, Shea; Stigler, Paula; Novotny, Thomas E

2015-01-01

This paper reviews several environmental principles, including Extended Producer Responsibility (EPR), Product Stewardship (PS), the Polluter Pays Principle (PPP), and the Precautionary Principle, as they may apply to tobacco product waste (TPW). The review addresses specific criteria that apply in deciding whether a particular toxic product should adhere to these principles; presents three case studies of similar approaches to other toxic and/or environmentally harmful products; and describes 10 possible interventions or policy actions that may help prevent, reduce, and mitigate the effects of TPW. EPR promotes total lifecycle environmental improvements, placing economic, physical, and informational responsibilities onto the tobacco industry, while PS complements EPR, but with responsibility shared by all parties involved in the tobacco product lifecycle. Both principles focus on toxic source reduction, post-consumer take-back, and final disposal of consumer products. These principles when applied to TPW have the potential to substantially decrease the environmental and public health harms of cigarette butts and other TPW throughout the world. TPW is the most commonly littered item picked up during environmental, urban, and coastal cleanups globally. PMID:26457262

The time-efficiency principle: time as the key diagnostic strategy in primary care.

PubMed

Irving, Greg; Holden, John

2013-08-01

The test and retest opportunity afforded by reviewing a patient over time substantially increases the total gain in certainty when making a diagnosis in low-prevalence settings (the time-efficiency principle). This approach safely and efficiently reduces the number of patients who need to be formally tested in order to make a correct diagnosis for a person. Time, in terms of observed disease trajectory, provides a vital mechanism for achieving this task. It remains the best strategy for delivering near-optimal diagnoses in low-prevalence settings and should be used to its full advantage.

Antitumor properties and modulation of antioxidant enzymes' activity by Aloe vera leaf active principles isolated via supercritical carbon dioxide extraction.

PubMed

El-Shemy, H A; Aboul-Soud, M A M; Nassr-Allah, A A; Aboul-Enein, K M; Kabash, A; Yagi, A

2010-01-01

The aim of this study was to evaluate the potential anticancer properties and modulatory effect of selected Aloe vera (A. vera) active principles on antioxidant enzyme activities. Thus, three anthraquinones (Namely: aloesin, aloe-emodin and barbaloin) were extracted from A. vera leaves by supercritical fluid extraction and subsequently purified by high performance liquid chromatography. Additionally, the N-terminal octapeptide derived from verectin, a biologically active 14 kDa glycoprotein present in A. vera, was also tested. In vivo, active principles exhibited significant prolongation of the life span of tumor-transplanted animals in the following order: barbaloin> octapeptide> aloesin > aloe-emodin. A. vera active principles exhibited significant inhibition on Ehrlich ascite carcinoma cell (EACC) number, when compared to positive control group, in the following order: barbaloin> aloe-emodin > octapeptide > aloesin. Moreover, in trypan blue cell viability assay, active principles showed a significant concentration-dependent cytotoxicity against acute myeloid leukemia (AML) and acute lymphocytes leukemia (ALL) cancerous cells. Furthermore, in MTT cell viability test, aloe-emodin was found to be active against two human colon cancer cell lines (i.e. DLD-1 and HT2), with IC(50) values of 8.94 and 10.78 microM, respectively. Treatments of human AML leukemic cells with active principles (100 microg ml(-1)) resulted in varying intensities of internucleosomal DNA fragmentation, hallmark of cells undergoing apoptosis, in the following order: aloe-emodin> aloesin> barbaloin> octapeptide. Intererstingly, treatment of EACC tumors with active principles resulted in a significant elevation activity of key antioxidant enzymes (SOD, GST, tGPx, and LDH). Our data suggest that the tested A. vera compounds may exert their chemo-preventive effect through modulating antioxidant and detoxification enzyme activity levels, as they are one of the indicators of tumorigenesis. These findings are discussed in the light of the potential of A. vera plant extracts for developing efficient, specific and non-toxic anticancer drugs that are affordable for developing countries.

Simulation-based crisis resource management training for pediatric critical care medicine: a review for instructors.

PubMed

Cheng, Adam; Donoghue, Aaron; Gilfoyle, Elaine; Eppich, Walter

2012-03-01

To review the essential elements of crisis resource management and provide a resource for instructors by describing how to use simulation-based training to teach crisis resource management principles in pediatric acute care contexts. A MEDLINE-based literature source. OUTLINE OF REVIEW: This review is divided into three main sections: Background, Principles of Crisis Resource Management, and Tools and Resources. The background section provides the brief history and definition of crisis resource management. The next section describes all the essential elements of crisis resource management, including leadership and followership, communication, teamwork, resource use, and situational awareness. This is followed by a review of evidence supporting the use of simulation-based crisis resource management training in health care. The last section provides the resources necessary to develop crisis resource management training using a simulation-based approach. This includes a description of how to design pediatric simulation scenarios, how to effectively debrief, and a list of potential assessment tools that instructors can use to evaluate crisis resource management performance during simulation-based training. Crisis resource management principles form the foundation for efficient team functioning and subsequent error reduction in high-stakes environments such as acute care pediatrics. Effective instructor training is required for those programs wishing to teach these principles using simulation-based learning. Dissemination and integration of these principles into pediatric critical care practice has the potential for a tremendous impact on patient safety and outcomes.

The protein structure prediction problem could be solved using the current PDB library

PubMed Central

Zhang, Yang; Skolnick, Jeffrey

2005-01-01

For single-domain proteins, we examine the completeness of the structures in the current Protein Data Bank (PDB) library for use in full-length model construction of unknown sequences. To address this issue, we employ a comprehensive benchmark set of 1,489 medium-size proteins that cover the PDB at the level of 35% sequence identity and identify templates by structure alignment. With homologous proteins excluded, we can always find similar folds to native with an average rms deviation (RMSD) from native of 2.5 Å with ≈82% alignment coverage. These template structures often contain a significant number of insertions/deletions. The tasser algorithm was applied to build full-length models, where continuous fragments are excised from the top-scoring templates and reassembled under the guide of an optimized force field, which includes consensus restraints taken from the templates and knowledge-based statistical potentials. For almost all targets (except for 2/1,489), the resultant full-length models have an RMSD to native below 6 Å (97% of them below 4 Å). On average, the RMSD of full-length models is 2.25 Å, with aligned regions improved from 2.5 Å to 1.88 Å, comparable with the accuracy of low-resolution experimental structures. Furthermore, starting from state-of-the-art structural alignments, we demonstrate a methodology that can consistently bring template-based alignments closer to native. These results are highly suggestive that the protein-folding problem can in principle be solved based on the current PDB library by developing efficient fold recognition algorithms that can recover such initial alignments. PMID:15653774

Salt Power: Is Neptune's Ole Salt a Tiger in the Tank?

ERIC Educational Resources Information Center

Wick, Gerry Shishin

1979-01-01

Discussed is the utilization of salinity-gradient energy as a potential source of power. Detailed are the scientific principles, potential sources, latest research, and environmental effects associated with this alternative energy source. The future prospects are addressed. (BT)

Nanocrystalline cellulose from coir fiber: preparation, properties, and applications

USDA-ARS?s Scientific Manuscript database

Nanocrystalline cellulose derived from various botanical sources offers unique and potentially useful characteristics. In principle, any cellulosic material can be considered as a potential source of a nanocrystalline material, including crops, crop residues, and agroindustrial wastes. Because of t...

Lean Production as an Innovative Approach to Construction

NASA Astrophysics Data System (ADS)

Spišáková, Marcela; Kozlovská, Mária

2013-06-01

Lean production presents a new approach to the construction management which has enabled enterprises to attain very high levels of efficiency, competitiveness and flexibility in production systems. Nowadays, a number of industrial processes are managed in accordance with these advanced management principles [1]. The principles of lean production are applied within the integrated design and delivery solutions (IDDS) and prefabricated construction. IDDS uses collaborative work processes and enhanced skills, with integrated data, information, and knowledge management to minimize structural and process inefficiencies and to enhance the value delivered during design, build, and operation, and across projects. Prefabrication presents a one of opportunities for construction methods, which allows the compliance with principles of sustainable design, provides the potential benefits such as faster construction, fewer housing defects, reduction in energy use and waste and elimination of environmental and safety risks. This paper presents the lean production within the IDDS and its potential in the modern prefabrication. There is created a field providing of benefits of lean production in construction industry.

Using engineering control principles to inform the design of adaptive interventions: a conceptual introduction.

PubMed

Rivera, Daniel E; Pew, Michael D; Collins, Linda M

2007-05-01

The goal of this paper is to describe the role that control engineering principles can play in developing and improving the efficacy of adaptive, time-varying interventions. It is demonstrated that adaptive interventions constitute a form of feedback control system in the context of behavioral health. Consequently, drawing from ideas in control engineering has the potential to significantly inform the analysis, design, and implementation of adaptive interventions, leading to improved adherence, better management of limited resources, a reduction of negative effects, and overall more effective interventions. This article illustrates how to express an adaptive intervention in control engineering terms, and how to use this framework in a computer simulation to investigate the anticipated impact of intervention design choices on efficacy. The potential benefits of operationalizing decision rules based on control engineering principles are particularly significant for adaptive interventions that involve multiple components or address co-morbidities, situations that pose significant challenges to conventional clinical practice.

Using Engineering Control Principles to Inform the Design of Adaptive Interventions: A Conceptual Introduction

PubMed Central

Rivera, Daniel E.; Pew, Michael D.; Collins, Linda M.

2007-01-01

The goal of this paper is to describe the role that control engineering principles can play in developing and improving the efficacy of adaptive, time-varying interventions. It is demonstrated that adaptive interventions constitute a form of feedback control system in the context of behavioral health. Consequently, drawing from ideas in control engineering has the potential to significantly inform the analysis, design, and implementation of adaptive interventions, leading to improved adherence, better management of limited resources, a reduction of negative effects, and overall more effective interventions. This article illustrates how to express an adaptive intervention in control engineering terms, and how to use this framework in a computer simulation to investigate the anticipated impact of intervention design choices on efficacy. The potential benefits of operationalizing decision rules based on control engineering principles are particularly significant for adaptive interventions that involve multiple components or address co-morbidities, situations that pose significant challenges to conventional clinical practice. PMID:17169503

First principles molecular dynamics of metal/water interfaces under bias potential

NASA Astrophysics Data System (ADS)

Pedroza, Luana; Brandimarte, Pedro; Rocha, Alexandre; Fernandez-Serra, Marivi

2014-03-01

Understanding the interaction of the water-metal system at an atomic level is extremely important in electrocatalysts for fuel cells, photocatalysis among other systems. The question of the interface energetics involves a detailed study of the nature of the interactions between water-water and water-substrate. A first principles description of all components of the system is the most appropriate methodology in order to advance understanding of electrochemically processes. In this work we describe, using first principles molecular dynamics simulations, the dynamics of a combined surface(Au and Pd)/water system both in the presence and absence of an external bias potential applied to the electrodes, as one would come across in electrochemistry. This is accomplished using a combination of density functional theory (DFT) and non-equilibrium Green's functions methods (NEGF), thus accounting for the fact that one is dealing with an out-of-equilibrium open system, with and without van der Waals interactions. DOE Early Career Award No. DE-SC0003871.

Preschool children use space, rather than counting, to infer the numerical magnitude of digits: Evidence for a spatial mapping principle.

PubMed

Sella, Francesco; Berteletti, Ilaria; Lucangeli, Daniela; Zorzi, Marco

2017-01-01

A milestone in numerical development is the acquisition of counting principles which allow children to exactly determine the numerosity of a given set. Moreover, a canonical left-to-right spatial layout for representing numbers also emerges during preschool. These foundational aspects of numerical competence have been extensively studied, but there is sparse knowledge about the interplay between the acquisition of the cardinality principle and spatial mapping of numbers in early numerical development. The present study investigated how these skills concurrently develop before formal schooling. Preschool children were classified according to their performance in Give-a-Number and Number-to-position tasks. Experiment 1 revealed three qualitatively different groups: (i) children who did not master the cardinality principle and lacked any consistent spatial mapping for digits, (ii) children who mastered the cardinality principle and yet failed in spatial mapping, and (iii) children who mastered the cardinality principle and displayed consistent spatial mapping. This suggests that mastery of the cardinality principle does not entail the emergence of spatial mapping. Experiment 2 confirmed the presence of these three developmental stages and investigated their relation with a digit comparison task. Crucially, only children who displayed a consistent spatial mapping of numbers showed the ability to compare digits by numerical magnitude. A congruent (i.e., numerically ordered) positioning of numbers onto a visual line as well as the concept that moving rightwards (in Western cultures) conveys an increase in numerical magnitude mark the mastery of a spatial mapping principle. Children seem to rely on this spatial organization to achieve a full understanding of the magnitude relations between digits. Copyright © 2016 Elsevier B.V. All rights reserved.

Title IV Cash Management Life Cycle Training. Participant's Guide.

ERIC Educational Resources Information Center

Department of Education, Washington, DC.

This participant's guide includes: "Introduction: Welcome to Cash Management Life Cycle Training"; "Module 1: Review of Cash Management Principles" (cash management overview and activity); "Module 2: Common Origination and Disbursement (COD) System Overview" (e.g., full participants and phase-in participants, COD…

The Forgotten Forest--New Training for Sawmillers and Wood Handlers.

ERIC Educational Resources Information Center

Ringling, Dennis F.

1978-01-01

Considers the full-time program in sawmilling and wood handling at Williamsport Area Community College (Pennsylvania), which stresses head sawing; edging and trimming processes; log and lumber grading; marketing and business principles; yard, storage, and kiln operations; and sawmill skills. (MB)

Insights into the activation mechanism of calcium ions on the sericite surface: A combined experimental and computational study

NASA Astrophysics Data System (ADS)

Hu, Yuehua; He, Jianyong; Zhang, Chenhu; Zhang, Chenyang; Sun, Wei; Zhao, Dongbo; Chen, Pan; Han, Haisheng; Gao, Zhiyong; Liu, Runqing; Wang, Li

2018-01-01

The adsorption behaviors and the activation mechanism of calcium ions (Ca2+) on sericite surface have been investigated by Zeta potential measurements, Fourier transform infrared spectroscopy (FT-IR), Micro-flotation tests and First principle calculations. Zeta potential tests results show that the sericite surface potential increases due to the adsorption of calcium ions on the surface. Micro-flotation tests demonstrate that sericite recovery remarkably rise by 10% due to the calcium ions activation on sericite surface. However, the characteristic adsorption bands of calcium oleate do not appear in the FT-IR spectrum, suggesting that oleate ions just physically adsorb on the sericite surface. The first principle calculations based on the density functional theory (DFT) further reveals the microscopic adsorption mechanism of calcium ions on the sericite surface before and after hydration.

A first principles calculation and statistical mechanics modeling of defects in Al-H system

NASA Astrophysics Data System (ADS)

Ji, Min; Wang, Cai-Zhuang; Ho, Kai-Ming

2007-03-01

The behavior of defects and hydrogen in Al was investigated by first principles calculations and statistical mechanics modeling. The formation energy of different defects in Al+H system such as Al vacancy, H in institution and multiple H in Al vacancy were calculated by first principles method. Defect concentration in thermodynamical equilibrium was studied by total free energy calculation including configuration entropy and defect-defect interaction from low concentration limit to hydride limit. In our grand canonical ensemble model, hydrogen chemical potential under different environment plays an important role in determing the defect concentration and properties in Al-H system.

Multimodal electromechanical model of piezoelectric transformers by Hamilton's principle.

PubMed

Nadal, Clement; Pigache, Francois

2009-11-01

This work deals with a general energetic approach to establish an accurate electromechanical model of a piezoelectric transformer (PT). Hamilton's principle is used to obtain the equations of motion for free vibrations. The modal characteristics (mass, stiffness, primary and secondary electromechanical conversion factors) are also deduced. Then, to illustrate this general electromechanical method, the variational principle is applied to both homogeneous and nonhomogeneous Rosen-type PT models. A comparison of modal parameters, mechanical displacements, and electrical potentials are presented for both models. Finally, the validity of the electrodynamical model of nonhomogeneous Rosen-type PT is confirmed by a numerical comparison based on a finite elements method and an experimental identification.

Building blocks for correlated superconductors and magnets

DOE PAGES

Sarrao, J. L.; Ronning, F.; Bauer, E. D.; ...

2015-04-01

Recent efforts at Los Alamos to discover strongly correlated superconductors and hard ferromagnets are reviewed. While serendipity remains a principal engine of materials discovery, design principles and structural building blocks are beginning to emerge that hold potential for predictive discovery. In addition, successes over the last decade with the so-called “115” strongly correlated superconductors are summarized, and more recent efforts to translate these insights and principles to novel hard magnets are discussed. While true “materials by design” remains a distant aspiration, progress is being made in coupling empirical design principles to electronic structure simulation to accelerate and guide materials designmore » and synthesis.« less

Polymer separations by liquid interaction chromatography: principles - prospects - limitations.

PubMed

Radke, Wolfgang

2014-03-28

Most heterogeneities of polymers with respect to different structural features cannot be resolved by only size exclusion chromatography (SEC), the most frequently applied mode of polymer chromatography. Instead, methods of interaction chromatography became increasingly important. However, despite the increasing applications the principles and potential of polymer interaction chromatography are still often unknown to a large number of polymer scientists. The present review will explain the principles of the different modes of polymer chromatography. Based on selected examples it will be shown which separation techniques can be successfully applied for separations with respect to the different structural features of polymers. Copyright © 2013 Elsevier B.V. All rights reserved.

Beyond electronegativity and local hardness: Higher-order equalization criteria for determination of a ground-state electron density.

PubMed

Ayers, Paul W; Parr, Robert G

2008-08-07

Higher-order global softnesses, local softnesses, and softness kernels are defined along with their hardness inverses. The local hardness equalization principle recently derived by the authors is extended to arbitrary order. The resulting hierarchy of equalization principles indicates that the electronegativity/chemical potential, local hardness, and local hyperhardnesses all are constant when evaluated for the ground-state electron density. The new equalization principles can be used to test whether a trial electron density is an accurate approximation to the true ground-state density and to discover molecules with desired reactive properties, as encapsulated by their chemical reactivity indicators.

Principled Missing Data Treatments.

PubMed

Lang, Kyle M; Little, Todd D

2018-04-01

We review a number of issues regarding missing data treatments for intervention and prevention researchers. Many of the common missing data practices in prevention research are still, unfortunately, ill-advised (e.g., use of listwise and pairwise deletion, insufficient use of auxiliary variables). Our goal is to promote better practice in the handling of missing data. We review the current state of missing data methodology and recent missing data reporting in prevention research. We describe antiquated, ad hoc missing data treatments and discuss their limitations. We discuss two modern, principled missing data treatments: multiple imputation and full information maximum likelihood, and we offer practical tips on how to best employ these methods in prevention research. The principled missing data treatments that we discuss are couched in terms of how they improve causal and statistical inference in the prevention sciences. Our recommendations are firmly grounded in missing data theory and well-validated statistical principles for handling the missing data issues that are ubiquitous in biosocial and prevention research. We augment our broad survey of missing data analysis with references to more exhaustive resources.

Capsizing Icebergs: An Exercise in the Application of the Principle of the Conservation of Energy with a Very Surprising Result

ERIC Educational Resources Information Center

Marshall, Rick

2015-01-01

Many icebergs are vulnerable to capsizing. In doing so the gravitational potential energy of the ice is increased, while that of the displaced sea water is decreased. Applying the principle of the conservation of energy shows that by capsizing, there is also a net transfer of energy to the surrounding sea water. This will be a maximum for a…

An Exercise in Evaluating the Contamination Potential of Surface Impoundments.

ERIC Educational Resources Information Center

Tinker, John R., Jr.

1982-01-01

Outlines a laboratory procedure which enables students to evaluate the contamination potential of surface impoundments and apply basic principles of hydrogeology to the land disposal of waste material. Includes a list of materials needed and directions for the instructor. (Author/DC)

Fundamental uncertainty limit of optical flow velocimetry according to Heisenberg's uncertainty principle.

PubMed

Fischer, Andreas

2016-11-01

Optical flow velocity measurements are important for understanding the complex behavior of flows. Although a huge variety of methods exist, they are either based on a Doppler or a time-of-flight measurement principle. Doppler velocimetry evaluates the velocity-dependent frequency shift of light scattered at a moving particle, whereas time-of-flight velocimetry evaluates the traveled distance of a scattering particle per time interval. Regarding the aim of achieving a minimal measurement uncertainty, it is unclear if one principle allows to achieve lower uncertainties or if both principles can achieve equal uncertainties. For this reason, the natural, fundamental uncertainty limit according to Heisenberg's uncertainty principle is derived for Doppler and time-of-flight measurement principles, respectively. The obtained limits of the velocity uncertainty are qualitatively identical showing, e.g., a direct proportionality for the absolute value of the velocity to the power of 32 and an indirect proportionality to the square root of the scattered light power. Hence, both measurement principles have identical potentials regarding the fundamental uncertainty limit due to the quantum mechanical behavior of photons. This fundamental limit can be attained (at least asymptotically) in reality either with Doppler or time-of-flight methods, because the respective Cramér-Rao bounds for dominating photon shot noise, which is modeled as white Poissonian noise, are identical with the conclusions from Heisenberg's uncertainty principle.

Interatomic potentials in condensed matter via the maximum-entropy principle

NASA Astrophysics Data System (ADS)

Carlsson, A. E.

1987-09-01

A general method is described for the calculation of interatomic potentials in condensed-matter systems by use of a maximum-entropy Ansatz for the interatomic correlation functions. The interatomic potentials are given explicitly in terms of statistical correlation functions involving the potential energy and the structure factor of a ``reference medium.'' Illustrations are given for Al-Cu alloys and a model transition metal.

Xenon Defects in Uranium Dioxide From First Principles and Interatomic Potentials

NASA Astrophysics Data System (ADS)

Thompson, Alexander

In this thesis, we examine the defect energetics and migration energies of xenon atoms in uranium dioxide (UO2) from first principles and interatomic potentials. We also parameterize new, accurate interatomic potentials for xenon and uranium dioxide. To achieve accurate energetics and provide a foundation for subsequent calculations, we address difficulties in finding consistent energetics within Hubbard U corrected density functional theory (DFT+U). We propose a method of slowly ramping the U parameter in order to guide the calculation into low energy orbital occupations. We find that this method is successful for a variety of materials. We then examine the defect energetics of several noble gas atoms in UO2 for several different defect sites. We show that the energy to incorporate large noble gas atoms into interstitial sites is so large that it is energetically favorable for a Schottky defect cluster to be created to relieve the strain. We find that, thermodynamically, xenon will rarely ever be in the interstitial site of UO2. To study larger defects associated with the migration of xenon in UO 2, we turn to interatomic potentials. We benchmark several previously published potentials against DFT+U defect energetics and migration barriers. Using a combination of molecular dynamics and nudged elastic band calculations, we find a new, low energy migration pathway for xenon in UO2. We create a new potential for xenon that yields accurate defect energetics. We fit this new potential with a method we call Iterative Potential Refinement that parameterizes potentials to first principles data via a genetic algorithm. The potential finds accurate energetics for defects with relatively low amounts of strain (xenon in defect clusters). It is important to find accurate energetics for these sorts of low-strain defects because they essentially represent small xenon bubbles. Finally, we parameterize a new UO2 potential that simultaneously yields accurate vibrational properties and defect energetics, important properties for UO2 because of the high temperature and defective reactor environment.. Previously published potentials could only yield accurate defect energetics or accurate phonons, but never both.

Le Chatelier Principle for Out-of-Equilibrium and Boundary-Driven Systems: Application to Dynamical Phase Transitions.

PubMed

Shpielberg, O; Akkermans, E

2016-06-17

A stability analysis is presented for boundary-driven and out-of-equilibrium systems in the framework of the hydrodynamic macroscopic fluctuation theory. A Hamiltonian description is proposed which allows us to thermodynamically interpret the additivity principle. A necessary and sufficient condition for the validity of the additivity principle is obtained as an extension of the Le Chatelier principle. These stability conditions result from a diagonal quadratic form obtained using the cumulant generating function. This approach allows us to provide a proof for the stability of the weakly asymmetric exclusion process and to reduce the search for stability to the solution of two coupled linear ordinary differential equations instead of nonlinear partial differential equations. Additional potential applications of these results are discussed in the realm of classical and quantum systems.

Le Chatelier Principle for Out-of-Equilibrium and Boundary-Driven Systems: Application to Dynamical Phase Transitions

NASA Astrophysics Data System (ADS)

Shpielberg, O.; Akkermans, E.

2016-06-01

A stability analysis is presented for boundary-driven and out-of-equilibrium systems in the framework of the hydrodynamic macroscopic fluctuation theory. A Hamiltonian description is proposed which allows us to thermodynamically interpret the additivity principle. A necessary and sufficient condition for the validity of the additivity principle is obtained as an extension of the Le Chatelier principle. These stability conditions result from a diagonal quadratic form obtained using the cumulant generating function. This approach allows us to provide a proof for the stability of the weakly asymmetric exclusion process and to reduce the search for stability to the solution of two coupled linear ordinary differential equations instead of nonlinear partial differential equations. Additional potential applications of these results are discussed in the realm of classical and quantum systems.

Insight into the optoelectronic and thermoelectric properties of Ca-based Zintl phase CaCd2X2 (X = P, As) from first principles calculation

NASA Astrophysics Data System (ADS)

Belfarh, T.; Batouche, M.; Seddik, T.; Uğur, G.; Omran, S. Bin; Bouhemadou, A.; Sandeep; Wang, Xiaotian; Sun, Xiao-Wei; Khenata, R.

2018-06-01

We have studied the structural, optical, electronic and thermoelectric properties of the CaCd2X2 (X = P, As) compounds by using the full-potential augmented plane wave plus local orbitals method (FP-APW + lo). The exchange-correlation potential was treated using both the gradient generalized approximation (WC-GGA) and local density approximation (LDA). The estimated structural parameters, including the lattice parameters and internal coordinates agree well with the available experimental data. Our computed band structure shows that both studied compounds are semiconductors, with direct band gaps (Γ-Γ) of approximately 1.78 eV and 1.2 eV for CaCd2P2 and CaCd2As2, respectively, using GGA-TB-mBJ approach. The calculated optical spectra reveal a strong response of these materials in the energy range between the visible light and extreme UV regions, making them a good candidate for optoelectronic devices. Thermoelectric parameters, such as thermal conductivity, electrical conductivity, Seebeck coefficient, power factor and figure of merit were calculated. We note that both the CaCd2P2 and CaCd2As2 compounds show promising thermoelectric properties.

Structural, electronic, elastic, thermoelectric and thermodynamic properties of the NbMSb half heusler (M=Fe, Ru, Os) compounds with first principle calculations

NASA Astrophysics Data System (ADS)

Abid, O. Miloud; Menouer, S.; Yakoubi, A.; Khachai, H.; Omran, S. Bin; Murtaza, G.; Prakash, Deo; Khenata, R.; Verma, K. D.

2016-05-01

The structural, electronic, elastic, thermoelectric and thermodynamic properties of NbMSb (M = Fe, Ru, Os) half heusler compounds are reported. The full-potential linearized augmented plane wave (FP-LAPW) plus local orbital (lo) method, based on the density functional theory (DFT) was employed for the present study. The equilibrium lattice parameter results are in good compliance with the available experimental measurements. The electronic band structure and Boltzmann transport calculations indicated a narrow indirect energy band gap for the compound having electronic structure favorable for thermoelectric performance as well as with substantial thermopowers at temperature ranges from 300 K to 800 K. Furthermore, good potential for thermoelectric performance (thermopower S ≥ 500 μeV) was found at higher temperature. In addition, the analysis of the charge density, partial and total densities of states (DOS) of three compounds demonstrate their semiconducting, ionic and covalent characters. Conversely, the calculated values of the Poisson's ratio and the B/G ratio indicate their ductile makeup. The thermal properties of the compounds were calculated by quasi-harmonic Debye model as implemented in the GIBBS code.

Molybdenum Oxide Nitrides of the Mo2(O,N,□)5 Type: On the Way to Mo2O5.

PubMed

Weber, Dominik; Huber, Manop; Gorelik, Tatiana E; Abakumov, Artem M; Becker, Nils; Niehaus, Oliver; Schwickert, Christian; Culver, Sean P; Boysen, Hans; Senyshyn, Anatoliy; Pöttgen, Rainer; Dronskowski, Richard; Ressler, Thorsten; Kolb, Ute; Lerch, Martin

2017-08-07

Blue-colored molybdenum oxide nitrides of the Mo 2 (O,N,□) 5 type were synthesized by direct nitridation of commercially available molybdenum trioxide with a mixture of gaseous ammonia and oxygen. Chemical composition, crystal structure, and stability of the obtained and hitherto unknown compounds are studied extensively. The average oxidation state of +5 for molybdenum is proven by Mo K near-edge X-ray absorption spectroscopy; the magnetic behavior is in agreement with compounds exhibiting Mo V O 6 units. The new materials are stable up to ∼773 K in an inert gas atmosphere. At higher temperatures, decomposition is observed. X-ray and neutron powder diffraction, electron diffraction, and high-resolution transmission electron microscopy reveal the structure to be related to VNb 9 O 24.9 -type phases, however, with severe disorder hampering full structure determination. Still, the results demonstrate the possibility of a future synthesis of the potential binary oxide Mo 2 O 5 . On the basis of these findings, a tentative suggestion on the crystal structure of the potential compound Mo 2 O 5 , backed by electronic-structure and phonon calculations from first principles, is given.

Thermodynamic integration of the free energy along a reaction coordinate in Cartesian coordinates

NASA Astrophysics Data System (ADS)

den Otter, W. K.

2000-05-01

A generalized formulation of the thermodynamic integration (TI) method for calculating the free energy along a reaction coordinate is derived. Molecular dynamics simulations with a constrained reaction coordinate are used to sample conformations. These are then projected onto conformations with a higher value of the reaction coordinate by means of a vector field. The accompanying change in potential energy plus the divergence of the vector field constitute the derivative of the free energy. Any vector field meeting some simple requirements can be used as the basis of this TI expression. Two classes of vector fields are of particular interest here. The first recovers the conventional TI expression, with its cumbersome dependence on a full set of generalized coordinates. As the free energy is a function of the reaction coordinate only, it should in principle be possible to derive an expression depending exclusively on the definition of the reaction coordinate. This objective is met by the second class of vector fields to be discussed. The potential of mean constraint force (PMCF) method, after averaging over the unconstrained momenta, falls in this second class. The new method is illustrated by calculations on the isomerization of n-butane, and is compared with existing methods.

Active and successful aging: a European policy perspective.

PubMed

Foster, Liam; Walker, Alan

2015-02-01

Over the past two decades, "active aging" has emerged in Europe as the foremost policy response to the challenges of population aging. This article examines the concept of active aging and how it differs from that of "successful aging." In particular, it shows how active aging presents a more holistic, life course-oriented approach than successful aging. We provide a critical perspective on active aging too by, first, tracing its emergence in Europe and then showing how, in practice, it has been dominated by a narrow economic or productivist perspective that prioritizes the extension of working life. It has also been gender blind. Nonetheless, it is argued that an active aging approach has the potential to enable countries to respond successfully to the challenges of population aging because of its comprehensive focus and emphasis on societal as well as individual responsibility. Finally, we set out the basic principles that need to be followed if the full potential of active aging is to be achieved. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Hybrid supercapacitor-battery materials for fast electrochemical charge storage

PubMed Central

Vlad, A.; Singh, N.; Rolland, J.; Melinte, S.; Ajayan, P. M.; Gohy, J.-F.

2014-01-01

High energy and high power electrochemical energy storage devices rely on different fundamental working principles - bulk vs. surface ion diffusion and electron conduction. Meeting both characteristics within a single or a pair of materials has been under intense investigations yet, severely hindered by intrinsic materials limitations. Here, we provide a solution to this issue and present an approach to design high energy and high power battery electrodes by hybridizing a nitroxide-polymer redox supercapacitor (PTMA) with a Li-ion battery material (LiFePO4). The PTMA constituent dominates the hybrid battery charge process and postpones the LiFePO4 voltage rise by virtue of its ultra-fast electrochemical response and higher working potential. We detail on a unique sequential charging mechanism in the hybrid electrode: PTMA undergoes oxidation to form high-potential redox species, which subsequently relax and charge the LiFePO4 by an internal charge transfer process. A rate capability equivalent to full battery recharge in less than 5 minutes is demonstrated. As a result of hybrid's components synergy, enhanced power and energy density as well as superior cycling stability are obtained, otherwise difficult to achieve from separate constituents. PMID:24603843

Functional Single-Walled Carbon Nanotubes and Nanoengineered Networks for Organic- and Perovskite-Solar-Cell Applications.

PubMed

Barbero, David R; Stranks, Samuel D

2016-11-01

Carbon nanotubes have a variety of remarkable electronic and mechanical properties that, in principle, lend them to promising optoelectronic applications. However, the field has been plagued by heterogeneity in the distributions of synthesized tubes and uncontrolled bundling, both of which have prevented nanotubes from reaching their full potential. Here, a variety of recently demonstrated solution-processing avenues is presented, which may combat these challenges through manipulation of nanoscale structures. Recent advances in polymer-wrapping of single-walled carbon nanotubes (SWNTs) are shown, along with how the resulting nanostructures can selectively disperse tubes while also exploiting the favorable properties of the polymer, such as light-harvesting ability. New methods to controllably form nanoengineered SWNT networks with controlled nanotube placement are discussed. These nanoengineered networks decrease bundling, lower the percolation threshold, and enable a strong enhancement in charge conductivity compared to random networks, making them potentially attractive for optoelectronic applications. Finally, SWNT applications, to date, in organic and perovskite photovoltaics are reviewed, and insights as to how the aforementioned recent advancements can lead to improved device performance provided. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Absence of B1-B2 structural transition in lithium halides under hydrostatic pressure

NASA Astrophysics Data System (ADS)

de Coss, Romeo; Murrieta, Gabriel

2005-03-01

We have investigated the B1-B2 structural transition in LiF, LiCl, LiBr, and LiI under hydrostatic pressure by means of first-principles total-energy calculations using the Full- Potential LAPW method. In order to analyze the gradient effects, we have performed calculations using the local density approximation (LDA) and the generalized gradient approximation (GGA), for the exchange and correlation potential. In agreement with the experimental observations, we find that even for pressures higher than 100 GPa, the Li halides do not present the B1-B2 structural transition. In order to understand this behavior, we have calculated the distribution of the electron densities. From the analysis of the distribution of electron densities for the Li halides in the B1 and B2 phases, we find that for this group of ionic compounds the B1 phase have a distribution of electron densities more homogeneous than in the B2 phase, preventing the B1-B2 structural transition. This work was partially supported by Consejo Nacional de Ciencia y Tecnolog'ia (CONACYT, M'exico) under Grant No. 43830-F.

Emerging principles in protease-based drug discovery

PubMed Central

Drag, Marcin; Salvesen, Guy S.

2010-01-01

Proteases have an important role in many signalling pathways, and represent potential drug targets for diseases ranging from cardiovascular disorders to cancer, as well as for combating many parasites and viruses. Although inhibitors of well-established protease targets such as angiotensin-converting enzyme and HIV protease have shown substantial therapeutic success, developing drugs for new protease targets has proved challenging in recent years. This in part could be due to issues such as the difficulty of achieving selectivity when targeting protease active sites. This Perspective discusses the general principles in protease-based drug discovery, highlighting the lessons learned and the emerging strategies, such as targeting allosteric sites, which could help harness the therapeutic potential of new protease targets. PMID:20811381

Studying Current-Potential Curves Using a Bipotentiometric Lodometric Back-Titration for the Determination of Ascorbic Acid in Fruits and Vegetables

ERIC Educational Resources Information Center

Verdini, Roxana A.; Lagier, Claudia M.

2004-01-01

Voltammetry principles are introduced to students by means of a bipotentiometric method to determine vitamin C in fruits and vegetables. The aim is to draw attention to voltammetric methods, particular to the study of current-potential curves, stressing the potential applicability in areas of food quality control.

Guide to Accreditation, 2011-2012

ERIC Educational Resources Information Center

Teacher Education Accreditation Council, 2011

2011-01-01

The Teacher Education Accreditation Council (TEAC) "Guide to Accreditation" includes a full description of TEAC's principles and standards, the accreditation process and audit, and detailed instruction on writing the "Brief." This revision includes expanded information on (1) preparing an "Inquiry Brief Proposal" and the audit of the "Inquiry…

40 CFR 86.884-9 - Smoke measurement system.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Schematic drawing. The Figure I84-1 is a schematic drawing of the optical system of the light extinction... the exhaust from the test site. (2) Smokemeter (light extinction meter)—continuous recording, full...) Light extinction meters employing substantially identical measurement principles and producing...

ADULT EDUCATION IN FRANCE.

ERIC Educational Resources Information Center

TITMUS, COLIN J.

A SURVEY OF NONVOCATIONAL ADULT EDUCATION IN FRANCE, THE FIRST FULL LENGTH STUDY, OUTLINES ITS HISTORY FROM THE FRENCH REVOLUTION THROUGH THE RESISTANCE, THE PRINCIPLES AND CONDITIONS OF POPULAR EDUCATION SINCE 1945, LOCAL AND GOVERNMENTAL PROGRAMS, SERVICES OF PRIVATE AND GENERAL ORGANIZATIONS, PROVISIONS FOR SPECIAL INTERESTS AND GROUPS,…

How to Present Evidence-Based Usability Design Principles Dedicated to Medication-Related Alerting Systems to Designers and Evaluators? Results from a Workshop.

PubMed

Marcilly, Romaric; Monkman, Helen; Villumsen, Sidsel; Kaufman, David; Beuscart-Zephir, Marie-Catherine

2016-01-01

Medication alerting system use errors and lack of adoption are often attributed to usability issues. Previous work has used evidence from the literature to reveal usability principles specific to medication alerting systems and identify potential consequences of violating these principles. The current study sought to explore how best to convey these principles to designers and evaluators of these systems to facilitate their work. To this aim, a workshop with 19 participants was used to generate ideas and opinions on how to deliver these topic-specific design principles in a way that would be most helpful for them. Participants generated ideas for how (e.g., a collaborative, continuously updated forum) and what (e.g., illustrations, checklists, evidence sources and strength, consequences of violations) information is most useful to disseminate usability principles for medication alerting systems. Participants, especially designers, expressed desire to use these principles in practice and avoid previously documented mistakes and therefore make design and evaluation of these systems more effective and efficient. Those insights are discussed in terms of feasibility and logistical challenges to developing the proposed documentation). To move this work forward, a more collaborative approach of Human Factors specialists in medical informatics is necessary.

Intrinsic imperfection of self-differencing single-photon detectors harms the security of high-speed quantum cryptography systems

NASA Astrophysics Data System (ADS)

Jiang, Mu-Sheng; Sun, Shi-Hai; Tang, Guang-Zhao; Ma, Xiang-Chun; Li, Chun-Yan; Liang, Lin-Mei

2013-12-01

Thanks to the high-speed self-differencing single-photon detector (SD-SPD), the secret key rate of quantum key distribution (QKD), which can, in principle, offer unconditionally secure private communications between two users (Alice and Bob), can exceed 1 Mbit/s. However, the SD-SPD may contain loopholes, which can be exploited by an eavesdropper (Eve) to hack into the unconditional security of the high-speed QKD systems. In this paper, we analyze the fact that the SD-SPD can be remotely controlled by Eve in order to spy on full information without being discovered, then proof-of-principle experiments are demonstrated. Here, we point out that this loophole is introduced directly by the operating principle of the SD-SPD, thus, it cannot be removed, except for the fact that some active countermeasures are applied by the legitimate parties.

Two applications of potential vorticity thinking

NASA Technical Reports Server (NTRS)

Robinson, Walter A.

1987-01-01

The phenomena of dissipative destabilization of external Rossby waves and the acceleration of the zonal mean jet during baroclinic life cycles are described in terms of potential vorticity. The main principle of the potential temperature variations at rigid boundaries have the same effect on the interior flow as do sheets of potential vorticity located just within the boundaries. It is noted that the potential vorticity theory is useful for understanding the dynamical behavior of meterological phenomena.

Cryptosporidium as a testbed for single cell genome characterization of unicellular eukaryotes.

PubMed

Troell, Karin; Hallström, Björn; Divne, Anna-Maria; Alsmark, Cecilia; Arrighi, Romanico; Huss, Mikael; Beser, Jessica; Bertilsson, Stefan

2016-06-23

Infectious disease involving multiple genetically distinct populations of pathogens is frequently concurrent, but difficult to detect or describe with current routine methodology. Cryptosporidium sp. is a widespread gastrointestinal protozoan of global significance in both animals and humans. It cannot be easily maintained in culture and infections of multiple strains have been reported. To explore the potential use of single cell genomics methodology for revealing genome-level variation in clinical samples from Cryptosporidium-infected hosts, we sorted individual oocysts for subsequent genome amplification and full-genome sequencing. Cells were identified with fluorescent antibodies with an 80 % success rate for the entire single cell genomics workflow, demonstrating that the methodology can be applied directly to purified fecal samples. Ten amplified genomes from sorted single cells were selected for genome sequencing and compared both to the original population and a reference genome in order to evaluate the accuracy and performance of the method. Single cell genome coverage was on average 81 % even with a moderate sequencing effort and by combining the 10 single cell genomes, the full genome was accounted for. By a comparison to the original sample, biological variation could be distinguished and separated from noise introduced in the amplification. As a proof of principle, we have demonstrated the power of applying single cell genomics to dissect infectious disease caused by closely related parasite species or subtypes. The workflow can easily be expanded and adapted to target other protozoans, and potential applications include mapping genome-encoded traits, virulence, pathogenicity, host specificity and resistance at the level of cells as truly meaningful biological units.

Evaluating statistical cloud schemes: What can we gain from ground-based remote sensing?

NASA Astrophysics Data System (ADS)

Grützun, V.; Quaas, J.; Morcrette, C. J.; Ament, F.

2013-09-01

Statistical cloud schemes with prognostic probability distribution functions have become more important in atmospheric modeling, especially since they are in principle scale adaptive and capture cloud physics in more detail. While in theory the schemes have a great potential, their accuracy is still questionable. High-resolution three-dimensional observational data of water vapor and cloud water, which could be used for testing them, are missing. We explore the potential of ground-based remote sensing such as lidar, microwave, and radar to evaluate prognostic distribution moments using the "perfect model approach." This means that we employ a high-resolution weather model as virtual reality and retrieve full three-dimensional atmospheric quantities and virtual ground-based observations. We then use statistics from the virtual observation to validate the modeled 3-D statistics. Since the data are entirely consistent, any discrepancy occurring is due to the method. Focusing on total water mixing ratio, we find that the mean ratio can be evaluated decently but that it strongly depends on the meteorological conditions as to whether the variance and skewness are reliable. Using some simple schematic description of different synoptic conditions, we show how statistics obtained from point or line measurements can be poor at representing the full three-dimensional distribution of water in the atmosphere. We argue that a careful analysis of measurement data and detailed knowledge of the meteorological situation is necessary to judge whether we can use the data for an evaluation of higher moments of the humidity distribution used by a statistical cloud scheme.

Schwinger-variational-principle theory of collisions in the presence of multiple potentials

NASA Astrophysics Data System (ADS)

Robicheaux, F.; Giannakeas, P.; Greene, Chris H.

2015-08-01

A theoretical method for treating collisions in the presence of multiple potentials is developed by employing the Schwinger variational principle. The current treatment agrees with the local (regularized) frame transformation theory and extends its capabilities. Specifically, the Schwinger variational approach gives results without the divergences that need to be regularized in other methods. Furthermore, it provides a framework to identify the origin of these singularities and possibly improve the local frame transformation. We have used the method to obtain the scattering parameters for different confining potentials symmetric in x ,y . The method is also used to treat photodetachment processes in the presence of various confining potentials, thereby highlighting effects of the infinitely many closed channels. Two general features predicted are the vanishing of the total photoabsorption probability at every channel threshold and the occurrence of resonances below the channel thresholds for negative scattering lengths. In addition, the case of negative-ion photodetachment in the presence of uniform magnetic fields is also considered where unique features emerge at large scattering lengths.

Drug-device combination products in the twenty-first century: epinephrine auto-injector development using human factors engineering.

PubMed

Edwards, Eric S; Edwards, Evan T; Simons, F Estelle R; North, Robert

2015-05-01

The systematic application of human factors engineering (HFE) principles to the development of drug-device combination products, including epinephrine auto-injectors (EAIs), has the potential to improve the effectiveness and safety of drug administration. A PubMed search was performed to assess the role of HFE in the development of drug-device combination products. The following keywords were used in different combinations: 'human factors engineering,' 'human factors,' 'medical products,' 'epinephrine/adrenaline auto-injector,' 'healthcare' and 'patient safety.' This review provides a summary of HFE principles and their application to the development of drug-device combination products as advised by the US FDA. It also describes the HFE process that was applied to the development of Auvi-Q, a novel EAI, highlighting specific steps that occurred during the product-development program. For drug-device combination products, device labeling and usability are critical and have the potential to impact clinical outcomes. Application of HFE principles to the development of drug-delivery devices has the potential to improve product quality and reliability, reduce risk and improve patient safety when applied early in the development process. Additional clinical and real-world studies will confirm whether the application of HFE has helped to develop an EAI that better meets the needs of patients at risk of anaphylaxis.

Principled Approaches to Missing Data in Epidemiologic Studies

PubMed Central

Perkins, Neil J; Cole, Stephen R; Harel, Ofer; Tchetgen Tchetgen, Eric J; Sun, BaoLuo; Mitchell, Emily M; Schisterman, Enrique F

2018-01-01

Abstract Principled methods with which to appropriately analyze missing data have long existed; however, broad implementation of these methods remains challenging. In this and 2 companion papers (Am J Epidemiol. 2018;187(3):576–584 and Am J Epidemiol. 2018;187(3):585–591), we discuss issues pertaining to missing data in the epidemiologic literature. We provide details regarding missing-data mechanisms and nomenclature and encourage the conduct of principled analyses through a detailed comparison of multiple imputation and inverse probability weighting. Data from the Collaborative Perinatal Project, a multisite US study conducted from 1959 to 1974, are used to create a masked data-analytical challenge with missing data induced by known mechanisms. We illustrate the deleterious effects of missing data with naive methods and show how principled methods can sometimes mitigate such effects. For example, when data were missing at random, naive methods showed a spurious protective effect of smoking on the risk of spontaneous abortion (odds ratio (OR) = 0.43, 95% confidence interval (CI): 0.19, 0.93), while implementation of principled methods multiple imputation (OR = 1.30, 95% CI: 0.95, 1.77) or augmented inverse probability weighting (OR = 1.40, 95% CI: 1.00, 1.97) provided estimates closer to the “true” full-data effect (OR = 1.31, 95% CI: 1.05, 1.64). We call for greater acknowledgement of and attention to missing data and for the broad use of principled missing-data methods in epidemiologic research. PMID:29165572

Principled Approaches to Missing Data in Epidemiologic Studies.

PubMed

Perkins, Neil J; Cole, Stephen R; Harel, Ofer; Tchetgen Tchetgen, Eric J; Sun, BaoLuo; Mitchell, Emily M; Schisterman, Enrique F

2018-03-01

Principled methods with which to appropriately analyze missing data have long existed; however, broad implementation of these methods remains challenging. In this and 2 companion papers (Am J Epidemiol. 2018;187(3):576-584 and Am J Epidemiol. 2018;187(3):585-591), we discuss issues pertaining to missing data in the epidemiologic literature. We provide details regarding missing-data mechanisms and nomenclature and encourage the conduct of principled analyses through a detailed comparison of multiple imputation and inverse probability weighting. Data from the Collaborative Perinatal Project, a multisite US study conducted from 1959 to 1974, are used to create a masked data-analytical challenge with missing data induced by known mechanisms. We illustrate the deleterious effects of missing data with naive methods and show how principled methods can sometimes mitigate such effects. For example, when data were missing at random, naive methods showed a spurious protective effect of smoking on the risk of spontaneous abortion (odds ratio (OR) = 0.43, 95% confidence interval (CI): 0.19, 0.93), while implementation of principled methods multiple imputation (OR = 1.30, 95% CI: 0.95, 1.77) or augmented inverse probability weighting (OR = 1.40, 95% CI: 1.00, 1.97) provided estimates closer to the "true" full-data effect (OR = 1.31, 95% CI: 1.05, 1.64). We call for greater acknowledgement of and attention to missing data and for the broad use of principled missing-data methods in epidemiologic research.

Precautionary principles: a jurisdiction-free framework for decision-making under risk.

PubMed

Ricci, Paolo F; Cox, Louis A; MacDonald, Thomas R

2004-12-01

Fundamental principles of precaution are legal maxims that ask for preventive actions, perhaps as contingent interim measures while relevant information about causality and harm remains unavailable, to minimize the societal impact of potentially severe or irreversible outcomes. Such principles do not explain how to make choices or how to identify what is protective when incomplete and inconsistent scientific evidence of causation characterizes the potential hazards. Rather, they entrust lower jurisdictions, such as agencies or authorities, to make current decisions while recognizing that future information can contradict the scientific basis that supported the initial decision. After reviewing and synthesizing national and international legal aspects of precautionary principles, this paper addresses the key question: How can society manage potentially severe, irreversible or serious environmental outcomes when variability, uncertainty, and limited causal knowledge characterize their decision-making? A decision-analytic solution is outlined that focuses on risky decisions and accounts for prior states of information and scientific beliefs that can be updated as subsequent information becomes available. As a practical and established approach to causal reasoning and decision-making under risk, inherent to precautionary decision-making, these (Bayesian) methods help decision-makers and stakeholders because they formally account for probabilistic outcomes, new information, and are consistent and replicable. Rational choice of an action from among various alternatives--defined as a choice that makes preferred consequences more likely--requires accounting for costs, benefits and the change in risks associated with each candidate action. Decisions under any form of the precautionary principle reviewed must account for the contingent nature of scientific information, creating a link to the decision-analytic principle of expected value of information (VOI), to show the relevance of new information, relative to the initial (and smaller) set of data on which the decision was based. We exemplify this seemingly simple situation using risk management of BSE. As an integral aspect of causal analysis under risk, the methods developed in this paper permit the addition of non-linear, hormetic dose-response models to the current set of regulatory defaults such as the linear, non-threshold models. This increase in the number of defaults is an important improvement because most of the variants of the precautionary principle require cost-benefit balancing. Specifically, increasing the set of causal defaults accounts for beneficial effects at very low doses. We also show and conclude that quantitative risk assessment dominates qualitative risk assessment, supporting the extension of the set of default causal models.

Principles of cancer prevention.

PubMed

Meyskens, Frank L; Tully, Patricia

2005-11-01

To summarize the scientific principles underlying cancer prevention. Articles, text books, personal communications, and experience. The scientific basis of cancer prevention is complex and involves experimental and epidemiologic approaches and clinical trials. As more information becomes available regarding proven and potential cancer-prevention strategies, oncology nurses are regularly called upon to guide patients and others in making choices regarding preventative options. It is important for oncology nurses to stay abreast of this growing body of knowledge.

Upon Further Review: A Commodity Chemist on Green Chemistry

NASA Astrophysics Data System (ADS)

Carroll, William F.

2016-09-01

Green chemistry is most often thought of in the context of specialty or pharmaceutical chemicals where many synthetic chemistry approaches are in play. However, principles similar to those of green chemistry and engineering were employed over the years in reducing cost and increasing volume of chemicals that became commodities. This paper considers some of those principles, their impact, and some perspectives on the potential and limits associated with green chemistry for commodity chemicals.

Acoustic levitation and the Boltzmann-Ehrenfest principle

NASA Technical Reports Server (NTRS)

Putterman, S.; Rudnick, Joseph; Barmatz, M.

1989-01-01

The Boltzmann-Ehrenfest principle of adiabatic invariance relates the acoustic potential acting on a sample positioned in a single-mode cavity to the shift in resonant frequency caused by the presence of this sample. This general and simple relation applies to samples and cavities of arbitrary shape, dimension, and compressibility. Positioning forces and torques can, therefore, be determined from straightforward measurements of frequency shifts. Applications to the Rayleigh disk phenomenon and levitated cylinders are presented.

Thermodynamics of firms' growth

PubMed Central

Zambrano, Eduardo; Hernando, Alberto; Hernando, Ricardo; Plastino, Angelo

2015-01-01

The distribution of firms' growth and firms' sizes is a topic under intense scrutiny. In this paper, we show that a thermodynamic model based on the maximum entropy principle, with dynamical prior information, can be constructed that adequately describes the dynamics and distribution of firms' growth. Our theoretical framework is tested against a comprehensive database of Spanish firms, which covers, to a very large extent, Spain's economic activity, with a total of 1 155 142 firms evolving along a full decade. We show that the empirical exponent of Pareto's law, a rule often observed in the rank distribution of large-size firms, is explained by the capacity of economic system for creating/destroying firms, and that can be used to measure the health of a capitalist-based economy. Indeed, our model predicts that when the exponent is larger than 1, creation of firms is favoured; when it is smaller than 1, destruction of firms is favoured instead; and when it equals 1 (matching Zipf's law), the system is in a full macroeconomic equilibrium, entailing ‘free’ creation and/or destruction of firms. For medium and smaller firm sizes, the dynamical regime changes, the whole distribution can no longer be fitted to a single simple analytical form and numerical prediction is required. Our model constitutes the basis for a full predictive framework regarding the economic evolution of an ensemble of firms. Such a structure can be potentially used to develop simulations and test hypothetical scenarios, such as economic crisis or the response to specific policy measures. PMID:26510828

Thermodynamics of firms' growth.

PubMed

Zambrano, Eduardo; Hernando, Alberto; Fernández Bariviera, Aurelio; Hernando, Ricardo; Plastino, Angelo

2015-11-06

The distribution of firms' growth and firms' sizes is a topic under intense scrutiny. In this paper, we show that a thermodynamic model based on the maximum entropy principle, with dynamical prior information, can be constructed that adequately describes the dynamics and distribution of firms' growth. Our theoretical framework is tested against a comprehensive database of Spanish firms, which covers, to a very large extent, Spain's economic activity, with a total of 1,155,142 firms evolving along a full decade. We show that the empirical exponent of Pareto's law, a rule often observed in the rank distribution of large-size firms, is explained by the capacity of economic system for creating/destroying firms, and that can be used to measure the health of a capitalist-based economy. Indeed, our model predicts that when the exponent is larger than 1, creation of firms is favoured; when it is smaller than 1, destruction of firms is favoured instead; and when it equals 1 (matching Zipf's law), the system is in a full macroeconomic equilibrium, entailing 'free' creation and/or destruction of firms. For medium and smaller firm sizes, the dynamical regime changes, the whole distribution can no longer be fitted to a single simple analytical form and numerical prediction is required. Our model constitutes the basis for a full predictive framework regarding the economic evolution of an ensemble of firms. Such a structure can be potentially used to develop simulations and test hypothetical scenarios, such as economic crisis or the response to specific policy measures. © 2015 The Authors.

Canonical fluid thermodynamics. [variational principles of stability for compressible adiabatic flow

NASA Technical Reports Server (NTRS)

Schmid, L. A.

1974-01-01

The space-time integral of the thermodynamic pressure plays in a certain sense the role of the thermodynamic potential for compressible adiabatic flow. The stability criterion can be converted into a variational minimum principle by requiring the molar free-enthalpy and temperature to be generalized velocities. In the fluid context, the definition of proper-time differentiation involves the fluid velocity expressed in terms of three particle identity parameters. The pressure function is then converted into a functional which is the Lagrangian density of the variational principle. Being also a minimum principle, the variational principle provides a means for comparing the relative stability of different flows. For boundary conditions with a high degree of symmetry, as in the case of a uniformly expanding spherical gas box, the most stable flow is a rectilinear flow for which the world-trajectory of each particle is a straight line. Since the behavior of the interior of a freely expanding cosmic cloud may be expected to be similar to that of the fluid in the spherical box of gas, this suggests that the cosmic principle is a consequence of the laws of thermodynamics, rather than just an ad hoc postulate.

Astounding Jumping Disk.

ERIC Educational Resources Information Center

Guzdziol, Edward S.

1991-01-01

Activities involving concave rubber disks are utilized to illustrate the scientific principles of kinetic and potential energy. Provides teacher instructions and questions related to the activity. (MDH)

Universal Design in Higher Education: From Principles to Practice

ERIC Educational Resources Information Center

Burgstahler, Sheryl E., Ed.; Cory, Rebecca C., Ed.

2008-01-01

"Universal Design in Higher Education" looks at the design of physical and technological environments at institutions of higher education; at issues pertaining to curriculum and instruction; and at the full array of student services. "Universal Design in Higher Education" is a comprehensive guide for researchers and…

Large Deviations for Stationary Probabilities of a Family of Continuous Time Markov Chains via Aubry-Mather Theory

NASA Astrophysics Data System (ADS)

Lopes, Artur O.; Neumann, Adriana

2015-05-01

In the present paper, we consider a family of continuous time symmetric random walks indexed by , . For each the matching random walk take values in the finite set of states ; notice that is a subset of , where is the unitary circle. The infinitesimal generator of such chain is denoted by . The stationary probability for such process converges to the uniform distribution on the circle, when . Here we want to study other natural measures, obtained via a limit on , that are concentrated on some points of . We will disturb this process by a potential and study for each the perturbed stationary measures of this new process when . We disturb the system considering a fixed potential and we will denote by the restriction of to . Then, we define a non-stochastic semigroup generated by the matrix , where is the infinifesimal generator of . From the continuous time Perron's Theorem one can normalized such semigroup, and, then we get another stochastic semigroup which generates a continuous time Markov Chain taking values on . This new chain is called the continuous time Gibbs state associated to the potential , see (Lopes et al. in J Stat Phys 152:894-933, 2013). The stationary probability vector for such Markov Chain is denoted by . We assume that the maximum of is attained in a unique point of , and from this will follow that . Thus, here, our main goal is to analyze the large deviation principle for the family , when . The deviation function , which is defined on , will be obtained from a procedure based on fixed points of the Lax-Oleinik operator and Aubry-Mather theory. In order to obtain the associated Lax-Oleinik operator we use the Varadhan's Lemma for the process . For a careful analysis of the problem we present full details of the proof of the Large Deviation Principle, in the Skorohod space, for such family of Markov Chains, when . Finally, we compute the entropy of the invariant probabilities on the Skorohod space associated to the Markov Chains we analyze.

Compositional bowing of band energies and their deformation potentials in strained InGaAs ternary alloys: A first-principles study

NASA Astrophysics Data System (ADS)

Khomyakov, Petr A.; Luisier, Mathieu; Schenk, Andreas

2015-08-01

Using first-principles calculations, we show that the conduction and valence band energies and their deformation potentials exhibit a non-negligible compositional bowing in strained ternary semiconductor alloys such as InGaAs. The electronic structure of these compounds has been calculated within the framework of local density approximation and hybrid functional approach for large cubic supercells and special quasi-random structures, which represent two kinds of model structures for random alloys. We find that the predicted bowing effect for the band energy deformation potentials is rather insensitive to the choice of the functional and alloy structural model. The direction of bowing is determined by In cations that give a stronger contribution to the formation of the InxGa1-xAs valence band states with x ≳ 0.5, compared to Ga cations.

Towards Principles-Based Approaches to Governance of Health-related Research using Personal Data

PubMed Central

Laurie, Graeme; Sethi, Nayha

2013-01-01

Technological advances in the quality, availability and linkage potential of health data for research make the need to develop robust and effective information governance mechanisms more pressing than ever before; they also lead us to question the utility of governance devices used hitherto such as consent and anonymisation. This article assesses and advocates a principles-based approach, contrasting this with traditional rule-based approaches, and proposes a model of principled proportionate governance. It is suggested that the approach not only serves as the basis for good governance in contemporary data linkage but also that it provides a platform to assess legal reforms such as the draft Data Protection Regulation. PMID:24416087

Towards Principles-Based Approaches to Governance of Health-related Research using Personal Data.

PubMed

Laurie, Graeme; Sethi, Nayha

2013-01-01

Technological advances in the quality, availability and linkage potential of health data for research make the need to develop robust and effective information governance mechanisms more pressing than ever before; they also lead us to question the utility of governance devices used hitherto such as consent and anonymisation. This article assesses and advocates a principles-based approach, contrasting this with traditional rule-based approaches, and proposes a model of principled proportionate governance . It is suggested that the approach not only serves as the basis for good governance in contemporary data linkage but also that it provides a platform to assess legal reforms such as the draft Data Protection Regulation.

Treatment Principles for the Management of Mold Infections

PubMed Central

Kontoyiannis, Dimitrios P.; Lewis, Russell E.

2015-01-01

Survival rates among immunocompromised patients with invasive mold infections have markedly improved over the last decade with earlier diagnosis and new antifungal treatment options. Yet, increasing antifungal resistance, breakthrough infections with intrinsically resistant fungi, and potentially life-threatening adverse effects and drug interactions are becoming more problematic, especially with prolonged therapy. Evidence-based recommendations for treating invasive aspergillosis and mucormycosis provide excellent guidance on the initial workup and treatment of these molds, but they cannot address all of the key management issues. Herein, we discuss 10 general treatment principles in the management of invasive mold disease in immunocompromised patients and discuss how these principles can be integrated to develop an effective, individualized treatment plan. PMID:25377139

Rapid and Automated Analytical Methods for Redox Species Based on Potentiometric Flow Injection Analysis Using Potential Buffers

PubMed Central

Ohura, Hiroki; Imato, Toshihiko

2011-01-01

Two analytical methods, which prove the utility of a potentiometric flow injection technique for determining various redox species, based on the use of some redox potential buffers, are reviewed. The first is a potentiometric flow injection method in which a redox couple such as Fe(III)-Fe(II), Fe(CN)6 3−-Fe(CN)(CN)6 4−, and bromide-bromine and a redox electrode or a combined platinum-bromide ion selective electrode are used. The analytical principle and advantages of the method are discussed, and several examples of its application are reported. Another example is a highly sensitive potentiometric flow injection method, in which a large transient potential change due to bromine or chlorine as an intermediate, generated during the reaction of the oxidative species with an Fe(III)-Fe(II) potential buffer containing bromide or chloride, is utilized. The analytical principle and details of the proposed method are described, and examples of several applications are described. The determination of trace amounts of hydrazine, based on the detection of a transient change in potential caused by the reaction with a Ce(IV)-Ce(III) potential buffer, is also described. PMID:21584280

The Evolution of TMD Diagnosis

PubMed Central

Ohrbach, R.; Dworkin, S.F.

2016-01-01

This review explores the principles and process associated with the diagnosis of temporomandibular disorders (TMDs). TMD diagnosis has evolved substantially over the past 25 y. Previously, diagnosis focused solely on aberrations in oral structures, largely without empirical evidence. The Research Diagnostic Criteria for TMD (RDC/TMD) were developed on core principles of 1) a dual-axis system reflecting the biopsychosocial model, 2) a clear operationalization for reliability, and 3) the allowance of multiple diagnoses. These principles were retained in the subsequent validation research of the RDC/TMD, and the current diagnostic system—the Diagnostic Criteria for TMD (DC/TMD)—has improved on those principles as well as on diagnostic validity and protocols for assessing the psychosocial domain. Further investigations into etiology and its potential contribution to taxonomy revision are described, particularly within the context of complex disease. The review concludes with an outline of major research areas already underway that will support future revisions of the DC/TMD. PMID:27313164

Ethical Challenges in Psychiatric Administration and Leadership.

PubMed

Moffic, H Steven; Saeed, Sy Atezaz; Silver, Stuart; Koh, Steve

2015-09-01

As with all professional ethical principles, those in psychiatry have to evolve over time and societal changes. The current ethical challenges for psychiatric administration and leadership, especially regarding for-profit managed care, need updated solutions. One solution resides in the development by the American Association of Psychiatric Administrators (AAPA) of the first set of ethical principles designed specifically for psychiatric administrators. These principles build on prior Psychological Theories of leadership, such as those of Freud, Kernberg, and Kohut. Supplementing these theories are the actual real life models of psychiatrist leadership as depicted in the memoirs of various psychiatrists. Appreciating these principles, theories, and models may help emerging leaders to better recognize the importance of ethical challenges. A conclusion is that psychiatrists should have the potential to assume more successful leadership positions once again. In such positions, making the skills and well-being of all in the organization seems now to be the foremost ethical priority.

Optimality Principles for Model-Based Prediction of Human Gait

PubMed Central

Ackermann, Marko; van den Bogert, Antonie J.

2010-01-01

Although humans have a large repertoire of potential movements, gait patterns tend to be stereotypical and appear to be selected according to optimality principles such as minimal energy. When applied to dynamic musculoskeletal models such optimality principles might be used to predict how a patient’s gait adapts to mechanical interventions such as prosthetic devices or surgery. In this paper we study the effects of different performance criteria on predicted gait patterns using a 2D musculoskeletal model. The associated optimal control problem for a family of different cost functions was solved utilizing the direct collocation method. It was found that fatigue-like cost functions produced realistic gait, with stance phase knee flexion, as opposed to energy-related cost functions which avoided knee flexion during the stance phase. We conclude that fatigue minimization may be one of the primary optimality principles governing human gait. PMID:20074736

Australian recommendations for the integration of emergency care for older people: Consensus Statement.

PubMed

Lowthian, Judy A; Arendts, Glenn; Strivens, Edward

2018-05-07

Management of older patients during acute illness or injury does not occur in isolation in emergency departments. We aimed to develop a collaborative Consensus Statement to enunciate principles of integrated emergency care. Briefing notes, informed by research and evidence reviews, were developed and evaluated by a Consensus Working Party comprising cross-specialty representation from clinical experts, service providers, consumers and policymakers. The Consensus Working Party then convened to discuss and develop the statement's content. A subcommittee produced a draft, which was reviewed and edited by the Consensus Working Party. Consensus was reached after three rounds of discussion, with 12 principles and six recommendations for how to follow these principles, including an integrated care framework for action. Dissemination will encourage stakeholders and associated policy bodies to embrace the principles and priorities for action, potentially leading to collaborative work practices and improvement of care during and after acute illness or injury. © 2018 AJA Inc.

Virtual data

NASA Astrophysics Data System (ADS)

Bjorklund, E.

1994-12-01

In the 1970s, when computers were memory limited, operating system designers created the concept of "virtual memory", which gave users the ability to address more memory than physically existed. In the 1990s, many large control systems have the potential of becoming data limited. We propose that many of the principles behind virtual memory systems (working sets, locality, caching and clustering) can also be applied to data-limited systems, creating, in effect, "virtual data systems". At the Los Alamos National Laboratory's Clinton P. Anderson Meson Physics Facility (LAMPF), we have applied these principles to a moderately sized (10 000 data points) data acquisition and control system. To test the principles, we measured the system's performance during tune-up, production, and maintenance periods. In this paper, we present a general discussion of the principles of a virtual data system along with some discussion of our own implementation and the results of our performance measurements.

Rotational quenching of H2O by He: mixed quantum/classical theory and comparison with quantum results.

PubMed

Ivanov, Mikhail; Dubernet, Marie-Lise; Babikov, Dmitri

2014-04-07

The mixed quantum/classical theory (MQCT) formulated in the space-fixed reference frame is used to compute quenching cross sections of several rotationally excited states of water molecule by impact of He atom in a broad range of collision energies, and is tested against the full-quantum calculations on the same potential energy surface. In current implementation of MQCT method, there are two major sources of errors: one affects results at energies below 10 cm(-1), while the other shows up at energies above 500 cm(-1). Namely, when the collision energy E is below the state-to-state transition energy ΔE the MQCT method becomes less accurate due to its intrinsic classical approximation, although employment of the average-velocity principle (scaling of collision energy in order to satisfy microscopic reversibility) helps dramatically. At higher energies, MQCT is expected to be accurate but in current implementation, in order to make calculations computationally affordable, we had to cut off the basis set size. This can be avoided by using a more efficient body-fixed formulation of MQCT. Overall, the errors of MQCT method are within 20% of the full-quantum results almost everywhere through four-orders-of-magnitude range of collision energies, except near resonances, where the errors are somewhat larger.

Principles and Recommendations for the Provision of Healthcare in Canada to Adolescent and Young Adult–Aged Cancer Patients and Survivors

PubMed Central

Fernandez, Conrad; Fraser, Graeme A.M.; Freeman, Carolyn; Grunfeld, Eva; Gupta, Abha; Mery, Leslie Stephen; De Pauw, Sonja

2011-01-01

Adolescents and young adults (AYA) with cancer and survivors of cancer in childhood, adolescence, and young adulthood are a constituency facing disparities of care affecting quality of life and other outcomes in many parts of the world. In Canada, this situation occurs in a nation with population-based cancer control programs and a government-funded healthcare system. The Canadian Task Force on Adolescents and Young Adults with Cancer was established in 2008 with a mission to ensure that AYA-aged Canadians with cancer and AYA survivors of cancer have prompt, equitable access to the best care, and to establish and support research to identify how their health outcomes and quality of life can be optimized. Following a survey of existing services, and in consultation with survivors, healthcare professionals, and policy makers, the Task Force identified principles of care, priority issues for research and the establishment of outcome metrics, and strategies for implementing change that are designed to improve the outcomes and quality of life of this specific cohort of patients and survivors with unique developmental needs. The six broad recommendations highlight the need for age-appropriate psychosocial, survivorship, palliative, and medical care as well as research to redress inequities in the care provided to this group relative to both younger and older cancer patients. Improved care for this group will enable individuals to reach their full potential as productive, functioning members of society, and will provide economic and other societal benefits. PMID:23610731

New Magneto-Inductive DC Magnetometer for Space Missions

NASA Astrophysics Data System (ADS)

Moldwin, M.; Bronner, B.; Regoli, L.; Thoma, J.; Shen, A.; Jenkins, G.; Cutler, J.

2017-12-01

A new magneto-inductive DC magnetometer is being developed at the University of Michigan that provides fluxgate quality measurements in a low mass, volume, power and cost package. The magnetometer enables constellation-class missions not only due to its low-resource requirements, but also its potential for commercial integrated circuit fabrication. The magneto-inductive operating principle is based on a simple resistance-inductor (RL) circuit and involves measurement of the time it takes to charge and discharge the inductor between an upper and lower threshold by means of a Schmitt trigger oscillator. This time is proportional to the inductance that in turn is proportional to the field strength. We have modeled the operating principle in the circuit simulator SPICE and have built a proto-type using modified commercial sensors. The performance specifications include a dynamic range over the full-Earth's field, sampling rates up to 80 Hz, sensor and electronics mass of about 30 g, circuit board and sensor housing volume of < 100 cm3, and power consumption of about 5 mW. This system's noise levels are predicted to be about 100 pT /√Hz @ 1 Hz with a precision of about 100 pT. Due to the simple circuit design, lack of an analog-to-digital converter, and choice of oscillator, we anticipate that it will be extremely temperature stable and radiation tolerant. This presentation will describe the constellation mission enabling design, the development status and the testing results of this new magnetometer.

Failure of the Hume-Rothery stabilization mechanism in the Ag(5)Li(8) gamma-brass studied by first-principles FLAPW electronic structure calculations.

PubMed

Mizutani, U; Asahi, R; Sato, H; Noritake, T; Takeuchi, T

2008-07-09

The first-principles FLAPW (full potential linearized augmented plane wave) electronic structure calculations were performed for the Ag(5)Li(8) gamma-brass, which contains 52 atoms in a unit cell and has been known for many years as one of the most structurally complex alloy phases. The calculations were also made for its neighboring phase AgLi B2 compound. The main objective in the present work is to examine if the Ag(5)Li(8) gamma-brass is stabilized at the particular electrons per atom ratio e/a = 21/13 in the same way as some other gamma-brasses like Cu(5)Zn(8) and Cu(9)Al(4), obeying the Hume-Rothery electron concentration rule. For this purpose, the e/a value for the Ag(5)Li(8) gamma-brass as well as the AgLi B2 compound was first determined by means of the FLAPW-Fourier method we have developed. It proved that both the gamma-brass and the B2 compound possess an e/a value equal to unity instead of 21/13. Moreover, we could demonstrate why the Hume-Rothery stabilization mechanism fails for the Ag(5)Li(8) gamma-brass and proposed a new stability mechanism, in which the unique gamma-brass structure can effectively lower the band-structure energy by forming heavily populated bonding states near the bottom of the Ag-4d band.

Discretization of three-dimensional free surface flows and moving boundary problems via elliptic grid methods based on variational principles

NASA Astrophysics Data System (ADS)

Fraggedakis, D.; Papaioannou, J.; Dimakopoulos, Y.; Tsamopoulos, J.

2017-09-01

A new boundary-fitted technique to describe free surface and moving boundary problems is presented. We have extended the 2D elliptic grid generator developed by Dimakopoulos and Tsamopoulos (2003) [19] and further advanced by Chatzidai et al. (2009) [18] to 3D geometries. The set of equations arises from the fulfillment of the variational principles established by Brackbill and Saltzman (1982) [21], and refined by Christodoulou and Scriven (1992) [22]. These account for both smoothness and orthogonality of the grid lines of tessellated physical domains. The elliptic-grid equations are accompanied by new boundary constraints and conditions which are based either on the equidistribution of the nodes on boundary surfaces or on the existing 2D quasi-elliptic grid methodologies. The capabilities of the proposed algorithm are first demonstrated in tests with analytically described complex surfaces. The sequence in which these tests are presented is chosen to help the reader build up experience on the best choice of the elliptic grid parameters. Subsequently, the mesh equations are coupled with the Navier-Stokes equations, in order to reveal the full potential of the proposed methodology in free surface flows. More specifically, the problem of gas assisted injection in ducts of circular and square cross-sections is examined, where the fluid domain experiences extreme deformations. Finally, the flow-mesh solver is used to calculate the equilibrium shapes of static menisci in capillary tubes.

A Template for an Intensive Ecohydrology Field Course

NASA Astrophysics Data System (ADS)

Emanuel, R. E.; McGlynn, B. L.; Riveros-Iregui, D. A.

2014-12-01

Many of the greatest challenges in the earth and environmental sciences are complex and interdisciplinary in nature. Ecohydrology exemplifies the type of holistic inquiry needed to address these challenges because it spans and integrates earth science, biological science and, often, social science. Ecohydrology courses can prepare the next generation of scientists, decision-makers and informed citizens to understand and address these challenges, and field courses in particular can play an important role in this preparation. Ecohydrology field course instructors have unique opportunities to convey interwoven theoretical and applied principles through a variety of modes that include lecture, discussion, immersion, and hands-on activity. In this presentation, we report on our experience co-teaching the Mountain Ecohydrology Field Course, a full-credit course taught 3 times in the past 5 years to more than 30 students representing 6 universities. The course, which has ranged from 1-2 weeks in length, has given students in-depth exposure to intensively instrumented ecohydrological field sites in the southern Appalachian and northern Rocky Mountains. Students learn fundamental principles in ecohydrology and related fields of watershed hydrology, soil biogeochemistry, micrometeorology and plant ecophysiology. They gain hands-on experience in a variety of cutting edge field techniques, tools and analyses while practicing presentation and communication of science. Students and instructors deal with real-world challenges of conducting fieldwork in remote settings. We offer our experience as one potential template for others interested in developing or refining ecohydrology field courses elsewhere.

Desynchronization of slow oscillations in the basal ganglia during natural sleep.

PubMed

Mizrahi-Kliger, Aviv D; Kaplan, Alexander; Israel, Zvi; Bergman, Hagai

2018-05-01

Slow oscillations of neuronal activity alternating between firing and silence are a hallmark of slow-wave sleep (SWS). These oscillations reflect the default activity present in all mammalian species, and are ubiquitous to anesthesia, brain slice preparations, and neuronal cultures. In all these cases, neuronal firing is highly synchronous within local circuits, suggesting that oscillation-synchronization coupling may be a governing principle of sleep physiology regardless of anatomical connectivity. To investigate whether this principle applies to overall brain organization, we recorded the activity of individual neurons from basal ganglia (BG) structures and the thalamocortical (TC) network over 70 full nights of natural sleep in two vervet monkeys. During SWS, BG neurons manifested slow oscillations (∼0.5 Hz) in firing rate that were as prominent as in the TC network. However, in sharp contrast to any neural substrate explored thus far, the slow oscillations in all BG structures were completely desynchronized between individual neurons. Furthermore, whereas in the TC network single-cell spiking was locked to slow oscillations in the local field potential (LFP), the BG LFP exhibited only weak slow oscillatory activity and failed to entrain nearby cells. We thus show that synchrony is not inherent to slow oscillations, and propose that the BG desynchronization of slow oscillations could stem from its unique anatomy and functional connectivity. Finally, we posit that BG slow-oscillation desynchronization may further the reemergence of slow-oscillation traveling waves from multiple independent origins in the frontal cortex, thus significantly contributing to normal SWS.

A unifying vision for scientific decision making: the Academy of Nutrition and Dietetics' Scientific Integrity Principles.

PubMed

Tappenden, Kelly A

2015-09-01

In 2014, recognizing the need to have a single document to guide scientific decision making at the Academy of Nutrition and Dietetics (Academy), the Council on Research was charged with developing a scientific integrity policy for the organization. From the Council on Research, four members volunteered to lead this workgroup, which reviewed the literature and best practices for scientific integrity from well-respected organizations, including federal funders of research. It became clear that the scope of this document would be quite broad, given the many scientific activities the Academy is involved in, and that it would be unreasonable to set policy for each of these many situations. Therefore, the workgroup set about defining the scope of scientific activities to be covered and envisioned a set of guiding principles, to which policies from every organizational unit of the Academy could be compared to ensure they were in alignment. While many relevant policies exist already, such as the requirement of a signed conflict of interest disclosure for Food & Nutrition Conference & Expo speakers, the Evidence Analysis Library funding policy, and the Academy's sponsorship policy, the scientific integrity principals are unique in that they provide a unifying vision to which future policies can be compared and approved based on their alignment with the principles. The six principles outlined in this article were approved by the full Council on Research in January 2015 and approved by the Academy's Board of Directors in March 2015. This article covers the scope of the principles, presents the principles and existing related resources, and outlines next steps for the Academy to review and revise current policies and create new ones in alignment with these principles. Copyright © 2015 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

How the Second Law of Thermodynamics Has Informed Ecosystem Ecology through Its History

NASA Astrophysics Data System (ADS)

Chapman, E. J.; Childers, D. L.; Vallino, J. J.

2014-12-01

Throughout the history of ecosystem ecology many attempts have been made to develop a general principle governing how systems develop and organize. We reviewed the historical developments that led to conceptualization of several goal-oriented principles in ecosystem ecology and the relationships among them. We focused our review on two prominent principles—the Maximum Power Principle and the Maximum Entropy Production Principle—and the literature that applies to both. While these principles have considerable conceptual overlap and both use concepts in physics (power and entropy), we found considerable differences in their historical development, the disciplines that apply these principles, and their adoption in the literature. We reviewed the literature using Web of Science keyword searches for the MPP, the MEPP, as well as for papers that cited pioneers in the MPP and the MEPP development. From the 6000 papers that our keyword searches returned, we limited our further meta-analysis to 32 papers by focusing on studies with a foundation in ecosystems research. Despite these seemingly disparate pasts, we concluded that the conceptual approaches of these two principles were more similar than dissimilar and that maximization of power in ecosystems occurs with maximum entropy production. We also found that these two principles have great potential to explain how systems develop, organize, and function, but there are no widely agreed upon theoretical derivations for the MEPP or the MPP, possibly hindering their broader use in ecological research. We end with recommendations for how ecosystems-level studies may better use these principles.

Real-time Series Resistance Monitoring in PV Systems; NREL (National Renewable Energy Laboratory)

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

Deceglie, M. G.; Silverman, T. J.; Marion, B.

We apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IV curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IVmore » curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on micro-inverters or module-integrated electronics, but it can also be extended to full strings. Automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks, including broken ribbons, broken solder bonds, and contact problems in the junction or combiner box. We describe the method in detail and describe a sample application to data collected from modules operating in the field.« less

Guiding principles of value creation through collaborative innovation in pharmaceutical research.

PubMed

Schweizer, Liang; He, Jeff

2018-02-01

Open innovation has become the main trend in pharmaceutical research. Potential obstacles and pitfalls of collaborations often lead to missed opportunities and/or poorly executed partnerships. This paper aims to provide a framework that facilitates the execution of successful collaborations. We start by mapping out three checkpoints onto early-stage collaborative partnerships: inception, ignition and implementation. Different value types and value drivers are then laid out for each phase of the partnership. We proceed to propose a ratio-driven approach and a value-adjustment mechanism, enhancing the probability of successes in pharmaceutical research collaborations. These guiding principles combined should help the partners either reach agreement more quickly or move on to the next potential project. Copyright © 2017 Elsevier Ltd. All rights reserved.

First principles cable braid electromagnetic penetration model

DOE PAGES

Warne, Larry Kevin; Langston, William L.; Basilio, Lorena I.; ...

2016-01-01

The model for penetration of a wire braid is rigorously formulated. Integral formulas are developed from energy principles for both self and transfer immittances in terms of potentials for the fields. The detailed boundary value problem for the wire braid is also set up in a very efficient manner; the braid wires act as sources for the potentials in the form of a sequence of line multi-poles with unknown coefficients that are determined by means of conditions arising from the wire surface boundary conditions. Approximations are introduced to relate the local properties of the braid wires to a simplified infinitemore » periodic planar geometry. Furthermore, this is used to treat nonuniform coaxial geometries including eccentric interior coaxial arrangements and an exterior ground plane.« less

Values and the Scientific Culture of Behavior Analysis

PubMed Central

Ruiz, Maria R; Roche, Bryan

2007-01-01

As scientists and practitioners, behavior analysts must make frequent decisions that affect many lives. Scientific principles have been our guide as we work to promote effective action across a broad spectrum of cultural practices. Yet scientific principles alone may not be sufficient to guide our decision making in cases with potentially conflicting outcomes. In such cases, values function as guides to work through ethical conflicts. We will examine two ethical systems, radical behaviorism and functional contextualism, from which to consider the role of values in behavior analysis, and discuss potential concerns. Finally, we propose philosophical pragmatism, focusing on John Dewey's notions of community and dialogue, as a tradition that can help behavior analysts to integrate talk about values and scientific practices in ethical decision making. PMID:22478484

The GS (genetic selection) Principle.

PubMed

Abel, David L

2009-01-01

The GS (Genetic Selection) Principle states that biological selection must occur at the nucleotide-sequencing molecular-genetic level of 3'5' phosphodiester bond formation. After-the-fact differential survival and reproduction of already-living phenotypic organisms (ordinary natural selection) does not explain polynucleotide prescription and coding. All life depends upon literal genetic algorithms. Even epigenetic and "genomic" factors such as regulation by DNA methylation, histone proteins and microRNAs are ultimately instructed by prior linear digital programming. Biological control requires selection of particular configurable switch-settings to achieve potential function. This occurs largely at the level of nucleotide selection, prior to the realization of any integrated biofunction. Each selection of a nucleotide corresponds to the setting of two formal binary logic gates. The setting of these switches only later determines folding and binding function through minimum-free-energy sinks. These sinks are determined by the primary structure of both the protein itself and the independently prescribed sequencing of chaperones. The GS Principle distinguishes selection of existing function (natural selection) from selection for potential function (formal selection at decision nodes, logic gates and configurable switch-settings).

Potential-Energy Surfaces, the Born-Oppenheimer Approximations, and the Franck-Condon Principle: Back to the Roots.

PubMed

Mustroph, Heinz

2016-09-05

The concept of a potential-energy surface (PES) is central to our understanding of spectroscopy, photochemistry, and chemical kinetics. However, the terminology used in connection with the basic approximations is variously, and somewhat confusingly, represented with such phrases as "adiabatic", "Born-Oppenheimer", or "Born-Oppenheimer adiabatic" approximation. Concerning the closely relevant and important Franck-Condon principle (FCP), the IUPAC definition differentiates between a classical and quantum mechanical formulation. Consequently, in many publications we find terms such as "Franck-Condon (excited) state", or a vertical transition to the "Franck-Condon point" with the "Franck-Condon geometry" that relaxes to the excited-state equilibrium geometry. The Born-Oppenheimer approximation and the "classical" model of the Franck-Condon principle are typical examples of misused terms and lax interpretations of the original theories. In this essay, we revisit the original publications of pioneers of the PES concept and the FCP to help stimulate a lively discussion and clearer thinking around these important concepts. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Achieving accuracy in first-principles calculations at extreme temperature and pressure

NASA Astrophysics Data System (ADS)

Mattsson, Ann; Wills, John

2013-06-01

First-principles calculations are increasingly used to provide EOS data at pressures and temperatures where experimental data is difficult or impossible to obtain. The lack of experimental data, however, also precludes validation of the calculations in those regimes. Factors influencing the accuracy of first-principles data include theoretical approximations, and computational approximations used in implementing and solving the underlying equations. The first category includes approximate exchange-correlation functionals and wave equations simplifying the Dirac equation. In the second category are, e.g., basis completeness and pseudo-potentials. While the first category is extremely hard to assess without experimental data, inaccuracies of the second type should be well controlled. We are using two rather different electronic structure methods (VASP and RSPt) to make explicit the requirements for accuracy of the second type. We will discuss the VASP Projector Augmented Wave potentials, with examples for Li and Mo. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

International University Co-operation: Summary Record of a Working Party on International University Co-operation. Papers-9.

ERIC Educational Resources Information Center

International Association of Universities, Paris (France).

This report delineates areas, patterns, effects, and purposes of international university cooperation. Areas of international university cooperation encompass teaching and study, research, university administration and organization. Patterns of cooperation include the basic principles of governing agreements, methods for full university…

42 CFR 482.25 - Condition of participation: Pharmaceutical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... registered pharmacist or a drug storage area under competent supervision. The medical staff is responsible... principles. (1) A full-time, part-time, or consulting pharmacist must be responsible for developing... under the supervision of a pharmacist and performed consistent with State and Federal laws. (2)(i) All...

42 CFR 482.25 - Condition of participation: Pharmaceutical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... registered pharmacist or a drug storage area under competent supervision. The medical staff is responsible... principles. (1) A full-time, part-time, or consulting pharmacist must be responsible for developing... under the supervision of a pharmacist and performed consistent with State and Federal laws. (2)(i) All...

42 CFR 482.25 - Condition of participation: Pharmaceutical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... registered pharmacist or a drug storage area under competent supervision. The medical staff is responsible... principles. (1) A full-time, part-time, or consulting pharmacist must be responsible for developing... under the supervision of a pharmacist and performed consistent with State and Federal laws. (2)(i) All...

42 CFR 482.25 - Condition of participation: Pharmaceutical services.

Code of Federal Regulations, 2010 CFR

2010-10-01

... registered pharmacist or a drug storage area under competent supervision. The medical staff is responsible... principles. (1) A full-time, part-time, or consulting pharmacist must be responsible for developing... under the supervision of a pharmacist and performed consistent with State and Federal laws. (2)(i) All...

42 CFR 482.25 - Condition of participation: Pharmaceutical services.

Code of Federal Regulations, 2011 CFR

2011-10-01

... registered pharmacist or a drug storage area under competent supervision. The medical staff is responsible... principles. (1) A full-time, part-time, or consulting pharmacist must be responsible for developing... under the supervision of a pharmacist and performed consistent with State and Federal laws. (2)(i) All...

40 CFR 310.19 - Under what conditions would EPA deny my request?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Under what conditions would EPA deny my request? We may deny your reimbursement request in full or in... accepted accounting principles and practices consistently applied; (b) The costs you claim are NOT... we request it; and (d) Reimbursement would be inconsistent with CERCLA section 123, or the...

The Basic Principle of Calculus?

ERIC Educational Resources Information Center

Hardy, Michael

2011-01-01

A simple partial version of the Fundamental Theorem of Calculus can be presented on the first day of the first-year calculus course, and then relied upon repeatedly in assigned problems throughout the course. With that experience behind them, students can use the partial version to understand the full-fledged Fundamental Theorem, with further…

Optics Demonstrations Using Cylindrical Lenses

ERIC Educational Resources Information Center

Ivanov, Dragia; Nikolov, Stefan

2015-01-01

In this paper we consider the main properties of cylindrical lenses and propose several demonstrational experiments that can be performed with them. Specifically we use simple glasses full of water to demonstrate some basic geometrical optics principles and phenomena. We also present some less standard experiments that can be performed with such…

Employment and Concepts of Work in the New Global Economy.

ERIC Educational Resources Information Center

Kelly, G. M.

2000-01-01

Gives an historical overview of the role and value of work from economic, philosophical, and legal perspectives. Stresses the need to humanize current globalization and technological trends in order to achieve the fundamental principle of the right to work and the objective of full employment. (SK)

Inclusive Education--A Sustainable Approach?

ERIC Educational Resources Information Center

Jokinen, Markku

2018-01-01

Full participation is one of the general principles in the United Nations Convention on the Rights of Persons with Disabilities (CRPD) for enabling the enjoyment of human rights. This concept cuts across all issues in the Convention, and is a specific obligation of states/parties that have ratified the Convention document. Other general principles…

MODELING THE INTERACTION THRESHOLD: THE BREAK-POINT BETWEEN ADDITIVITY AND NON-ADDITIVITY

EPA Science Inventory

Dose-dependent changes in toxicity mechanisms of single chemicals may take place along the full dose-response spectrum. At high doses, the possibility exists for some steps in the principle mechanism of toxicity to shift to other mechanisms. The possibility of mechanism shifts fo...

49 CFR 383.95 - Restrictions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... applicant either fails the air brake component of the knowledge test, or performs the skills test in a... the skills test and the restriction, air brakes include any braking system operating fully or partially on the air brake principle. (b) Full air brake. (1) If an applicant performs the skills test in a...

Classroom Assessment. Third Edition.

ERIC Educational Resources Information Center

Airasian, Peter W.

"Classroom Assessment" is designed for students taking a first course in classroom assessment and measurement. It shows how assessment principles apply to the full range of teacher decision making, and not just the formal evaluation of student learning. For this reason, the book has been organized in a manner that follows the natural progression…

An Ultrastable Heterobimetallic Uranium(IV)/Vanadium(III) Solid Compound Protected by a Redox-Active Phosphite Ligand: Crystal Structure, Oxidative Dissolution, and First-Principles Simulation.

PubMed

Gui, Daxiang; Dai, Xing; Zheng, Tao; Wang, Xiangxiang; Silver, Mark A; Chen, Lanhua; Zhang, Chao; Diwu, Juan; Zhou, Ruhong; Chai, Zhifang; Wang, Shuao

2018-02-05

The first heterobimetallic uranium(IV)/vanadium(III) phosphite compound, Na 2 UV 2 (HPO 3 ) 6 (denoted as UVP), was synthesized via an in situ redox-active hydrothermal reaction. It exhibits superior hydrolytic and antioxidant stability compared to the majority of structures containing low-valent uranium or vanadium, further elucidated by first-principles simulations, and therefore shows potential applications in nuclear waste management.

Perspectives on the design of safer nanomaterials and manufacturing processes

NASA Astrophysics Data System (ADS)

Geraci, Charles; Heidel, Donna; Sayes, Christie; Hodson, Laura; Schulte, Paul; Eastlake, Adrienne; Brenner, Sara

2015-09-01

A concerted effort is being made to insert Prevention through Design principles into discussions of sustainability, occupational safety and health, and green chemistry related to nanotechnology. Prevention through Design is a set of principles, which includes solutions to design out potential hazards in nanomanufacturing including the design of nanomaterials, and strategies to eliminate exposures and minimize risks that may be related to the manufacturing processes and equipment at various stages of the lifecycle of an engineered nanomaterial.

Policy on synthetic biology: deliberation, probability, and the precautionary paradox.

PubMed

Wareham, Christopher; Nardini, Cecilia

2015-02-01

Synthetic biology is a cutting-edge area of research that holds the promise of unprecedented health benefits. However, in tandem with these large prospective benefits, synthetic biology projects entail a risk of catastrophic consequences whose severity may exceed that of most ordinary human undertakings. This is due to the peculiar nature of synthetic biology as a 'threshold technology' which opens doors to opportunities and applications that are essentially unpredictable. Fears about these potentially unstoppable consequences have led to declarations from civil society groups calling for the use of a precautionary principle to regulate the field. Moreover, the principle is prevalent in law and international agreements. Despite widespread political recognition of a need for caution, the precautionary principle has been extensively criticized as a guide for regulatory policy. We examine a central objection to the principle: that its application entails crippling inaction and incoherence, since whatever action one takes there is always a chance that some highly improbable cataclysm will occur. In response to this difficulty, which we call the 'precautionary paradox,' we outline a deliberative means for arriving at threshold of probability below which potential dangers can be disregarded. In addition, we describe a Bayesian mechanism with which to assign probabilities to harmful outcomes. We argue that these steps resolve the paradox. The rehabilitated PP can thus provide a viable policy option to confront the uncharted waters of synthetic biology research. © 2013 John Wiley & Sons Ltd.

A multi-directional backlight for a wide-angle, glasses-free three-dimensional display.

PubMed

Fattal, David; Peng, Zhen; Tran, Tho; Vo, Sonny; Fiorentino, Marco; Brug, Jim; Beausoleil, Raymond G

2013-03-21

Multiview three-dimensional (3D) displays can project the correct perspectives of a 3D image in many spatial directions simultaneously. They provide a 3D stereoscopic experience to many viewers at the same time with full motion parallax and do not require special glasses or eye tracking. None of the leading multiview 3D solutions is particularly well suited to mobile devices (watches, mobile phones or tablets), which require the combination of a thin, portable form factor, a high spatial resolution and a wide full-parallax view zone (for short viewing distance from potentially steep angles). Here we introduce a multi-directional diffractive backlight technology that permits the rendering of high-resolution, full-parallax 3D images in a very wide view zone (up to 180 degrees in principle) at an observation distance of up to a metre. The key to our design is a guided-wave illumination technique based on light-emitting diodes that produces wide-angle multiview images in colour from a thin planar transparent lightguide. Pixels associated with different views or colours are spatially multiplexed and can be independently addressed and modulated at video rate using an external shutter plane. To illustrate the capabilities of this technology, we use simple ink masks or a high-resolution commercial liquid-crystal display unit to demonstrate passive and active (30 frames per second) modulation of a 64-view backlight, producing 3D images with a spatial resolution of 88 pixels per inch and full-motion parallax in an unprecedented view zone of 90 degrees. We also present several transparent hand-held prototypes showing animated sequences of up to six different 200-view images at a resolution of 127 pixels per inch.

Conservative relativity principle: Logical ground and analysis of relevant experiments

NASA Astrophysics Data System (ADS)

Kholmetskii, Alexander; Yarman, Tolga; Missevitch, Oleg

2014-05-01

We suggest a new relativity principle, which asserts the impossibility to distinguish the state of rest and the state of motion at the constant velocity of a system, if no work is done to the system in question during its motion. We suggest calling this new rule as "conservative relativity principle" (CRP). In the case of an empty space, CRP is reduced to the Einstein special relativity principle. We also show that CRP is compatible with the general relativity principle. One of important implications of CRP is the dependence of the proper time of a charged particle on the electric potential at its location. In the present paper we consider the relevant experimental facts gathered up to now, where the latter effect can be revealed. We show that in atomic physics the introduction of this effect furnishes a better convergence between theory and experiment than that provided by the standard approach. Finally, we reanalyze the Mössbauer experiments in rotating systems and show that the obtained recently puzzling deviation of the relative energy shift between emission and absorption lines from the relativistic prediction can be explained by the CRP.

Evolutionary principles and their practical application

PubMed Central

Hendry, Andrew P; Kinnison, Michael T; Heino, Mikko; Day, Troy; Smith, Thomas B; Fitt, Gary; Bergstrom, Carl T; Oakeshott, John; Jørgensen, Peter S; Zalucki, Myron P; Gilchrist, George; Southerton, Simon; Sih, Andrew; Strauss, Sharon; Denison, Robert F; Carroll, Scott P

2011-01-01

Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently in these different fields, even though the underlying fundamental concepts are the same. We explore these fundamental concepts under four main themes: variation, selection, connectivity, and eco-evolutionary dynamics. Within each theme, we present several key evolutionary principles and illustrate their use in addressing applied problems. We hope that the resulting primer of evolutionary concepts and their practical utility helps to advance a unified multidisciplinary field of applied evolutionary biology. PMID:25567966

Evolutionary principles and their practical application.

PubMed

Hendry, Andrew P; Kinnison, Michael T; Heino, Mikko; Day, Troy; Smith, Thomas B; Fitt, Gary; Bergstrom, Carl T; Oakeshott, John; Jørgensen, Peter S; Zalucki, Myron P; Gilchrist, George; Southerton, Simon; Sih, Andrew; Strauss, Sharon; Denison, Robert F; Carroll, Scott P

2011-03-01

Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently in these different fields, even though the underlying fundamental concepts are the same. We explore these fundamental concepts under four main themes: variation, selection, connectivity, and eco-evolutionary dynamics. Within each theme, we present several key evolutionary principles and illustrate their use in addressing applied problems. We hope that the resulting primer of evolutionary concepts and their practical utility helps to advance a unified multidisciplinary field of applied evolutionary biology.

Applying the intention-to-treat principle in practice: Guidance on handling randomisation errors

PubMed Central

Sullivan, Thomas R; Voysey, Merryn; Lee, Katherine J; Cook, Jonathan A; Forbes, Andrew B

2015-01-01

Background: The intention-to-treat principle states that all randomised participants should be analysed in their randomised group. The implications of this principle are widely discussed in relation to the analysis, but have received limited attention in the context of handling errors that occur during the randomisation process. The aims of this article are to (1) demonstrate the potential pitfalls of attempting to correct randomisation errors and (2) provide guidance on handling common randomisation errors when they are discovered that maintains the goals of the intention-to-treat principle. Methods: The potential pitfalls of attempting to correct randomisation errors are demonstrated and guidance on handling common errors is provided, using examples from our own experiences. Results: We illustrate the problems that can occur when attempts are made to correct randomisation errors and argue that documenting, rather than correcting these errors, is most consistent with the intention-to-treat principle. When a participant is randomised using incorrect baseline information, we recommend accepting the randomisation but recording the correct baseline data. If ineligible participants are inadvertently randomised, we advocate keeping them in the trial and collecting all relevant data but seeking clinical input to determine their appropriate course of management, unless they can be excluded in an objective and unbiased manner. When multiple randomisations are performed in error for the same participant, we suggest retaining the initial randomisation and either disregarding the second randomisation if only one set of data will be obtained for the participant, or retaining the second randomisation otherwise. When participants are issued the incorrect treatment at the time of randomisation, we propose documenting the treatment received and seeking clinical input regarding the ongoing treatment of the participant. Conclusion: Randomisation errors are almost inevitable and should be reported in trial publications. The intention-to-treat principle is useful for guiding responses to randomisation errors when they are discovered. PMID:26033877

Applying the intention-to-treat principle in practice: Guidance on handling randomisation errors.

PubMed

Yelland, Lisa N; Sullivan, Thomas R; Voysey, Merryn; Lee, Katherine J; Cook, Jonathan A; Forbes, Andrew B

2015-08-01

The intention-to-treat principle states that all randomised participants should be analysed in their randomised group. The implications of this principle are widely discussed in relation to the analysis, but have received limited attention in the context of handling errors that occur during the randomisation process. The aims of this article are to (1) demonstrate the potential pitfalls of attempting to correct randomisation errors and (2) provide guidance on handling common randomisation errors when they are discovered that maintains the goals of the intention-to-treat principle. The potential pitfalls of attempting to correct randomisation errors are demonstrated and guidance on handling common errors is provided, using examples from our own experiences. We illustrate the problems that can occur when attempts are made to correct randomisation errors and argue that documenting, rather than correcting these errors, is most consistent with the intention-to-treat principle. When a participant is randomised using incorrect baseline information, we recommend accepting the randomisation but recording the correct baseline data. If ineligible participants are inadvertently randomised, we advocate keeping them in the trial and collecting all relevant data but seeking clinical input to determine their appropriate course of management, unless they can be excluded in an objective and unbiased manner. When multiple randomisations are performed in error for the same participant, we suggest retaining the initial randomisation and either disregarding the second randomisation if only one set of data will be obtained for the participant, or retaining the second randomisation otherwise. When participants are issued the incorrect treatment at the time of randomisation, we propose documenting the treatment received and seeking clinical input regarding the ongoing treatment of the participant. Randomisation errors are almost inevitable and should be reported in trial publications. The intention-to-treat principle is useful for guiding responses to randomisation errors when they are discovered. © The Author(s) 2015.

BioCapacitor: A novel principle for biosensors.

PubMed

Sode, Koji; Yamazaki, Tomohiko; Lee, Inyoung; Hanashi, Takuya; Tsugawa, Wakako

2016-02-15

Studies regarding biofuel cells utilizing biocatalysts such as enzymes and microorganisms as electrocatalysts have been vigorously conducted over the last two decades. Because of their environmental safety and sustainability, biofuel cells are expected to be used as clean power generators. Among several principles of biofuel cells, enzyme fuel cells have attracted significant attention for their use as alternative energy sources for future implantable devices, such as implantable insulin pumps and glucose sensors in artificial pancreas and pacemakers. However, the inherent issue of the biofuel cell principle is the low power of a single biofuel cell. The theoretical voltage of biofuel cells is limited by the redox potential of cofactors and/or mediators employed in the anode and cathode, which are inadequate for operating any devices used for biomedical application. These limitations inspired us to develop a novel biodevice based on an enzyme fuel cell that generates sufficient stable power to operate electric devices, designated "BioCapacitor." To increase voltage, the enzyme fuel cell is connected to a charge pump. To obtain a sufficient power and voltage to operate an electric device, a capacitor is used to store the potential generated by the charge pump. Using the combination of a charge pump and capacitor with an enzyme fuel cell, high voltages with sufficient temporary currents to operate an electric device were generated without changing the design and construction of the enzyme fuel cell. In this review, the BioCapacitor principle is described. The three different representative categories of biodevices employing the BioCapacitor principle are introduced. Further, the recent challenges in the developments of self-powered stand-alone biodevices employing enzyme fuel cells combined with charge pumps and capacitors are introduced. Finally, the future prospects of biodevices employing the BioCapacitor principle are addressed. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Scalar/Vector potential formulation for compressible viscous unsteady flows

NASA Technical Reports Server (NTRS)

Morino, L.

1985-01-01

A scalar/vector potential formulation for unsteady viscous compressible flows is presented. The scalar/vector potential formulation is based on the classical Helmholtz decomposition of any vector field into the sum of an irrotational and a solenoidal field. The formulation is derived from fundamental principles of mechanics and thermodynamics. The governing equations for the scalar potential and vector potential are obtained, without restrictive assumptions on either the equation of state or the constitutive relations or the stress tensor and the heat flux vector.

Foundations of quantum gravity: The role of principles grounded in empirical reality

NASA Astrophysics Data System (ADS)

Holman, Marc

2014-05-01

When attempting to assess the strengths and weaknesses of various principles in their potential role of guiding the formulation of a theory of quantum gravity, it is crucial to distinguish between principles which are strongly supported by empirical data - either directly or indirectly - and principles which instead (merely) rely heavily on theoretical arguments for their justification. Principles in the latter category are not necessarily invalid, but their a priori foundational significance should be regarded with due caution. These remarks are illustrated in terms of the current standard models of cosmology and particle physics, as well as their respective underlying theories, i.e., essentially general relativity and quantum (field) theory. For instance, it is clear that both standard models are severely constrained by symmetry principles: an effective homogeneity and isotropy of the known universe on the largest scales in the case of cosmology and an underlying exact gauge symmetry of nuclear and electromagnetic interactions in the case of particle physics. However, in sharp contrast to the cosmological situation, where the relevant symmetry structure is more or less established directly on observational grounds, all known, nontrivial arguments for the "gauge principle" are purely theoretical (and far less conclusive than usually advocated). Similar remarks apply to the larger theoretical structures represented by general relativity and quantum (field) theory, where - actual or potential - empirical principles, such as the (Einstein) equivalence principle or EPR-type nonlocality, should be clearly differentiated from theoretical ones, such as general covariance or renormalizability. It is argued that if history is to be of any guidance, the best chance to obtain the key structural features of a putative quantum gravity theory is by deducing them, in some form, from the appropriate empirical principles (analogous to the manner in which, say, the idea that gravitation is a curved spacetime phenomenon is arguably implied by the equivalence principle). Theoretical principles may still be useful however in formulating a concrete theory (analogous to the manner in which, say, a suitable form of general covariance can still act as a sieve for separating theories of gravity from one another). It is subsequently argued that the appropriate empirical principles for deducing the key structural features of quantum gravity should at least include (i) quantum nonlocality, (ii) irreducible indeterminacy (or, essentially equivalently, given (i), relativistic causality), (iii) the thermodynamic arrow of time, (iv) homogeneity and isotropy of the observable universe on the largest scales. In each case, it is explained - when appropriate - how the principle in question could be implemented mathematically in a theory of quantum gravity, why it is considered to be of fundamental significance and also why contemporary accounts of it are insufficient. For instance, the high degree of uniformity observed in the Cosmic Microwave Background is usually regarded as theoretically problematic because of the existence of particle horizons, whereas the currently popular attempts to resolve this situation in terms of inflationary models are, for a number of reasons, less than satisfactory. However, rather than trying to account for the required empirical features dynamically, an arguably much more fruitful approach consists in attempting to account for these features directly, in the form of a lawlike initial condition within a theory of quantum gravity.

Minimization principles for the coupled problem of Darcy-Biot-type fluid transport in porous media linked to phase field modeling of fracture

NASA Astrophysics Data System (ADS)

Miehe, Christian; Mauthe, Steffen; Teichtmeister, Stephan

2015-09-01

This work develops new minimization and saddle point principles for the coupled problem of Darcy-Biot-type fluid transport in porous media at fracture. It shows that the quasi-static problem of elastically deforming, fluid-saturated porous media is related to a minimization principle for the evolution problem. This two-field principle determines the rate of deformation and the fluid mass flux vector. It provides a canonically compact model structure, where the stress equilibrium and the inverse Darcy's law appear as the Euler equations of a variational statement. A Legendre transformation of the dissipation potential relates the minimization principle to a characteristic three field saddle point principle, whose Euler equations determine the evolutions of deformation and fluid content as well as Darcy's law. A further geometric assumption results in modified variational principles for a simplified theory, where the fluid content is linked to the volumetric deformation. The existence of these variational principles underlines inherent symmetries of Darcy-Biot theories of porous media. This can be exploited in the numerical implementation by the construction of time- and space-discrete variational principles, which fully determine the update problems of typical time stepping schemes. Here, the proposed minimization principle for the coupled problem is advantageous with regard to a new unconstrained stable finite element design, while space discretizations of the saddle point principles are constrained by the LBB condition. The variational principles developed provide the most fundamental approach to the discretization of nonlinear fluid-structure interactions, showing symmetric systems in algebraic update procedures. They also provide an excellent starting point for extensions towards more complex problems. This is demonstrated by developing a minimization principle for a phase field description of fracture in fluid-saturated porous media. It is designed for an incorporation of alternative crack driving forces, such as a convenient criterion in terms of the effective stress. The proposed setting provides a modeling framework for the analysis of complex problems such as hydraulic fracture. This is demonstrated by a spectrum of model simulations.

Resistance training interventions across the cancer control continuum: a systematic review of the implementation of resistance training principles.

PubMed

Fairman, C M; Hyde, P N; Focht, B C

2017-04-01

The primary purpose of this systematic review is to examine the extant resistance training (RT) cancer research to evaluate the proportion of RT interventions that: (1) implemented key RT training principles (specificity, progression, overload) and (2) explicitly reported relevant RT prescription components (frequency, intensity, sets, reps). A qualitative systematic review was performed by two reviewers (CMF and PNH) who inspected the titles and abstracts to determine eligibility for this systematic review. Identified papers were obtained in full and further reviewed. Data were extracted to evaluate the application of principles of training, along with specific RT components. Electronic databases (PubMed, EMBASE, CINAHL, Cochrane, PEDro, PsychInfo, Cancer Lit, Sport Discus, AMED, Cochrane Central Register of Controlled Trials) and reference lists of included articles from inception to May 2016. 37 studies were included. The principle of specificity was used appropriately in all of the studies, progression in 65% and overload in 76% of the studies. The most common exercise prescription (∼50%) implemented in the studies included in this review were 2-3 days/week, focusing on large muscle groups, 60-70% 1 repetition maximum (RM), 1-3 sets of 8-12 repetitions. Reporting of RT principles in an oncology setting varies greatly, with often vague or non-existent references to the principles of training and how the RT prescription was designed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

A critique of the molecular target-based drug discovery paradigm based on principles of metabolic control: advantages of pathway-based discovery.

PubMed

Hellerstein, Marc K

2008-01-01

Contemporary drug discovery and development (DDD) is dominated by a molecular target-based paradigm. Molecular targets that are potentially important in disease are physically characterized; chemical entities that interact with these targets are identified by ex vivo high-throughput screening assays, and optimized lead compounds enter testing as drugs. Contrary to highly publicized claims, the ascendance of this approach has in fact resulted in the lowest rate of new drug approvals in a generation. The primary explanation for low rates of new drugs is attrition, or the failure of candidates identified by molecular target-based methods to advance successfully through the DDD process. In this essay, I advance the thesis that this failure was predictable, based on modern principles of metabolic control that have emerged and been applied most forcefully in the field of metabolic engineering. These principles, such as the robustness of flux distributions, address connectivity relationships in complex metabolic networks and make it unlikely a priori that modulating most molecular targets will have predictable, beneficial functional outcomes. These same principles also suggest, however, that unexpected therapeutic actions will be common for agents that have any effect (i.e., that complexity can be exploited therapeutically). A potential operational solution (pathway-based DDD), based on observability rather than predictability, is described, focusing on emergent properties of key metabolic pathways in vivo. Recent examples of pathway-based DDD are described. In summary, the molecular target-based DDD paradigm is built on a naïve and misleading model of biologic control and is not heuristically adequate for advancing the mission of modern therapeutics. New approaches that take account of and are built on principles described by metabolic engineers are needed for the next generation of DDD.

Effect of doping on electronic properties of HgSe

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

Nag, Abhinav, E-mail: abhinavn76@gmail.com; Sastri, O. S. K. S., E-mail: sastri.osks@gmail.com; Kumar, Jagdish, E-mail: jagdishphysicist@gmail.com

2016-05-23

First principle study of electronic properties of pure and doped HgSe have been performed using all electron Full Potential Linearized Augmented Plane Wave (FP-LAPW) method using ELK code. The electronic exchange and co-relations are considered using Generalized Gradient Approach (GGA). Lattice parameter, Density of States (DOS) and Band structure calculations have been performed. The total energy curve (Energy vs Lattice parameter), DOS and band structure calculations are in good agreement with the experimental values and those obtained using other DFT codes. The doped material is studied within the Virtual Crystal Approximation (VCA) with doping levels of 10% to 25% ofmore » electrons (hole) per unit cell. Results predict zero band gap in undopedHgSe and bands meet at Fermi level near the symmetry point Γ. For doped HgSe, we found that by electron (hole) doping, the point where conduction and valence bands meet can be shifted below (above) the fermi level.« less

Simultaneous in-plane and out-of-plane displacement measurement based on a dual-camera imaging system and its application to inspection of large-scale space structures

NASA Astrophysics Data System (ADS)

Ri, Shien; Tsuda, Hiroshi; Yoshida, Takeshi; Umebayashi, Takashi; Sato, Akiyoshi; Sato, Eiichi

2015-07-01

Optical methods providing full-field deformation data have potentially enormous interest for mechanical engineers. In this study, an in-plane and out-of-plane displacement measurement method based on a dual-camera imaging system is proposed. The in-plane and out-of-plane displacements are determined simultaneously using two measured in-plane displacement data observed from two digital cameras at different view angles. The fundamental measurement principle and experimental results of accuracy confirmation are presented. In addition, we applied this method to the displacement measurement in a static loading and bending test of a solid rocket motor case (CFRP material; 2.2 m diameter and 2.3 m long) for an up-to-date Epsilon rocket developed by JAXA. The effectiveness and measurement accuracy is confirmed by comparing with conventional displacement sensor. This method could be useful to diagnose the reliability of large-scale space structures in the rocket development.

Quality assurance in pathology in colorectal cancer screening and diagnosis—European recommendations

PubMed Central

Quirke, Phil; Risio, Mauro; Lambert, René; von Karsa, Lawrence

2010-01-01

In Europe, colorectal cancer is the most common newly diagnosed cancer and the second most common cause of cancer deaths, accounting for approximately 436,000 incident cases and 212,000 deaths in 2008. The potential of high-quality screening to improve control of the disease has been recognized by the Council of the European Union who issued a recommendation on cancer screening in 2003. Multidisciplinary, evidence-based European Guidelines for quality assurance in colorectal cancer screening and diagnosis have recently been developed by experts in a pan-European project coordinated by the International Agency for Research on Cancer. The full guideline document consists of ten chapters and an extensive evidence base. The content of the chapter dealing with pathology in colorectal cancer screening and diagnosis is presented here in order to promote international discussion and collaboration leading to improvements in colorectal cancer screening and diagnosis by making the principles and standards recommended in the new EU Guidelines known to a wider scientific community. PMID:21061133

Structure of the cold- and menthol-sensing ion channel TRPM8.

PubMed

Yin, Ying; Wu, Mengyu; Zubcevic, Lejla; Borschel, William F; Lander, Gabriel C; Lee, Seok-Yong

2018-01-12

Transient receptor potential melastatin (TRPM) cation channels are polymodal sensors that are involved in a variety of physiological processes. Within the TRPM family, member 8 (TRPM8) is the primary cold and menthol sensor in humans. We determined the cryo-electron microscopy structure of the full-length TRPM8 from the collared flycatcher at an overall resolution of ~4.1 ångstroms. Our TRPM8 structure reveals a three-layered architecture. The amino-terminal domain with a fold distinct among known TRP structures, together with the carboxyl-terminal region, forms a large two-layered cytosolic ring that extensively interacts with the transmembrane channel layer. The structure suggests that the menthol-binding site is located within the voltage-sensor-like domain and thus provides a structural glimpse of the design principle of the molecular transducer for cold and menthol sensation. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Ethical adoption: A new imperative in the development of technology for dementia.

PubMed

Robillard, Julie M; Cleland, Ian; Hoey, Jesse; Nugent, Chris

2018-06-19

Technology interventions are showing promise to assist persons with dementia and their carers. However, low adoption rates for these technologies and ethical considerations have impeded the realization of their full potential. Building on recent evidence and an iterative framework development process, we propose the concept of "ethical adoption": the deep integration of ethical principles into the design, development, deployment, and usage of technology. Ethical adoption is founded on five pillars, supported by empirical evidence: (1) inclusive participatory design; (2) emotional alignment; (3) adoption modelling; (4) ethical standards assessment; and (5) education and training. To close the gap between adoption research, ethics and practice, we propose a set of 18 practical recommendations based on these ethical adoption pillars. Through the implementation of these recommendations, researchers and technology developers alike will benefit from evidence-informed guidance to ensure their solution is adopted in a way that maximizes the benefits to people with dementia and their carers while minimizing possible harm. Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Wide-angle camera with multichannel architecture using microlenses on a curved surface.

PubMed

Liang, Wei-Lun; Shen, Hui-Kai; Su, Guo-Dung J

2014-06-10

We propose a multichannel imaging system that combines the principles of an insect's compound eye and the human eye. The optical system enables a reduction in track length of the imaging device to achieve miniaturization. The multichannel structure is achieved by a curved microlens array, and a Hypergon lens is used as the main lens to simulate the human eye, achieving large field of view (FOV). With this architecture, each microlens of the array transmits a segment of the overall FOV. The partial images are recorded in separate channels and stitched together to form the final image of the whole FOV by image processing. The design is 2.7 mm thick, with 59 channels; the 100°×80° full FOV is optimized using ZEMAX ray-tracing software on an image plane. The image plane size is 4.53  mm×3.29  mm. Given the recent progress in the fabrication of microlenses, this image system has the potential to be commercialized in the near future.

Definition of rational antiepileptic polypharmacy.

PubMed

Wilder, B J; Homan, R W

1996-01-01

Rational polypharmacy is in its earliest stages of development and will require substantial additional development to realize its full potential. Indeed, despite the powerful appeal of the concept, clinical proof is not yet available that RP is superior to monotherapy. Important questions need to be addressed: 1. Will RP control seizures more effectively than monotherapy? 2. What data are needed to develop RP for a specific patient? 3. Will RP be cost effective? 4. Can RP be developed which will treat or prevent epilepsy while controlling seizures? Possible approaches to these questions could include: 1. The development of a data base for prospective use to monitor patients being treated at Epilepsy Centers using RP principles. 2. Use the data obtained from the above to construct more specific studies to compare identified combination therapies with monotherapy. 3. Prospectively compare in a placebo controlled, blinded study, the effect of the combination of an anti-ictal medication and a laboratory proven antiepileptic drug for prevention of the development of epilepsy in an at risk population such as head trauma or stroke.

Searching for beauty-fully bound tetraquarks using lattice nonrelativistic QCD

NASA Astrophysics Data System (ADS)

Hughes, Ciaran; Eichten, Estia; Davies, Christine T. H.

2018-03-01

Motivated by multiple phenomenological considerations, we perform the first search for the existence of a b ¯b ¯b b tetraquark bound state with a mass below the lowest noninteracting bottomonium-pair threshold using the first-principles lattice nonrelativistic QCD methodology. We use a full S -wave color/spin basis for the b ¯b ¯b b operators in the three 0++, 1+- and 2++ channels. We employ four gluon field ensembles at multiple lattice spacing values ranging from a =0.06 - 0.12 fm , all of which include u , d , s and c quarks in the sea, and one ensemble which has physical light-quark masses. Additionally, we perform novel exploratory work with the objective of highlighting any signal of a near threshold tetraquark, if it existed, by adding an auxiliary potential into the QCD interactions. With our results we find no evidence of a QCD bound tetraquark below the lowest noninteracting thresholds in the channels studied.

Comparative study of the compensated semi-metals LaBi and LuBi: a first-principles approach.

PubMed

Dey, Urmimala

2018-05-23

We have investigated the electronic structures of LaBi and LuBi, employing the full-potential all electron method as implemented in Wien2k. Using this, we have studied in detail both the bulk and the surface states of these materials. From our band structure calculations we find that LuBi, like LaBi, is a compensated semi-metal with almost equal and sizable electron and hole pockets. In analogy with experimental evidence in LaBi, we thus predict that LuBi will also be a candidate for extremely large magneto-resistance (XMR), which should be of immense technological interest. Our calculations reveal that LaBi, despite being gapless in the bulk spectrum, displays the characteristic features of a [Formula: see text] topological semi-metal, resulting in gapless Dirac cones on the surface, whereas LuBi only shows avoided band inversion in the bulk and is thus a conventional compensated semi-metal with extremely large magneto-resistance.

Comparative study of the compensated semi-metals LaBi and LuBi: a first-principles approach

NASA Astrophysics Data System (ADS)

Dey, Urmimala

2018-05-01

We have investigated the electronic structures of LaBi and LuBi, employing the full-potential all electron method as implemented in Wien2k. Using this, we have studied in detail both the bulk and the surface states of these materials. From our band structure calculations we find that LuBi, like LaBi, is a compensated semi-metal with almost equal and sizable electron and hole pockets. In analogy with experimental evidence in LaBi, we thus predict that LuBi will also be a candidate for extremely large magneto-resistance (XMR), which should be of immense technological interest. Our calculations reveal that LaBi, despite being gapless in the bulk spectrum, displays the characteristic features of a topological semi-metal, resulting in gapless Dirac cones on the surface, whereas LuBi only shows avoided band inversion in the bulk and is thus a conventional compensated semi-metal with extremely large magneto-resistance.

Enhancing the capability of the research fleet.

NASA Astrophysics Data System (ADS)

Pinkel, R.

2012-12-01

While the performance and economics of our vessels and manned platforms are fixed by fundamental principles, their scientific capabilities can be considerably extended through the development of new technology. Potential future systems include multi-beam swath- mapping sonars for 3-D imaging of plankton patchiness, wire-guided profiling velocity sensors for establishing full-ocean-depth velocity profiles, shipboard HF radar (CODAR) for mapping energetic currents, and shipboard Doppler radar for mapping the surface wave spectrum. Research vessel users should have access to undersea gliders and autonomous aircraft as well as the current AUVs. In addition, the use of manned stable platforms in an observatory setting deserves further consideration. As well as providing an ideal mount for meteorological and oceanographic sensors, the platforms can provide electrical power and a "heavy lift" capability for sea floor and water column studies. Concerted community effort will be required to develop these new technologies, not all of which will be commercially viable. A strong academic technology base is necessary.

Searching for beauty-fully bound tetraquarks using lattice nonrelativistic QCD

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

Hughes, Ciaran; Eichten, Estia; Davies, Christine T. H.

Motivated by multiple phenomenological considerations, we perform the first search for the existence of amore » $$\\bar{bb}bb$$ tetraquark bound state with a mass below the lowest noninteracting bottomonium-pair threshold using the first-principles lattice nonrelativistic QCD methodology. Here, we use a full S-wave color/spin basis for the $$\\bar{bb}bb$$ operators in the three 0 ++, 1 +- and 2 ++ channels. We employ four gluon field ensembles at multiple lattice spacing values ranging from a=0.06–0.12 fm, all of which include u, d, s and c quarks in the sea, and one ensemble which has physical light-quark masses. Additionally, we perform novel exploratory work with the objective of highlighting any signal of a near threshold tetraquark, if it existed, by adding an auxiliary potential into the QCD interactions. With our results we find no evidence of a QCD bound tetraquark below the lowest noninteracting thresholds in the channels studied.« less

A case study of the Secure Anonymous Information Linkage (SAIL) Gateway: a privacy-protecting remote access system for health-related research and evaluation.

PubMed

Jones, Kerina H; Ford, David V; Jones, Chris; Dsilva, Rohan; Thompson, Simon; Brooks, Caroline J; Heaven, Martin L; Thayer, Daniel S; McNerney, Cynthia L; Lyons, Ronan A

2014-08-01

With the current expansion of data linkage research, the challenge is to find the balance between preserving the privacy of person-level data whilst making these data accessible for use to their full potential. We describe a privacy-protecting safe haven and secure remote access system, referred to as the Secure Anonymised Information Linkage (SAIL) Gateway. The Gateway provides data users with a familiar Windows interface and their usual toolsets to access approved anonymously-linked datasets for research and evaluation. We outline the principles and operating model of the Gateway, the features provided to users within the secure environment, and how we are approaching the challenges of making data safely accessible to increasing numbers of research users. The Gateway represents a powerful analytical environment and has been designed to be scalable and adaptable to meet the needs of the rapidly growing data linkage community. Copyright © 2014 The Aurthors. Published by Elsevier Inc. All rights reserved.

Lonely GPFUTV-the movement of water under the action of unknown vacuum

NASA Astrophysics Data System (ADS)

Lin, Weiyi

2013-11-01

In this paper, firstly, the experiment on the flow resistance of the aerated pipe flow is introduced. The experimental research on comparison between different volumes of air entrained is presented. Secondly, the characteristics of gravity pipe flow under the action of Torricelli's vacuum, shortly called as GPFUTV are dissertated, including creative and functional design, fundamental principle, etc. Under the joint action of an unknown vacuum energy and the formation of non-aerated flow the water flow is full-pipe and continuous, high-speed and non-rotational as distinguished from turbulent flow. Thirdly, an appeal in relation to the experimental research, the applied studies and basic theory research is given. For instance, experimental study of Torricelli's experiment phenomenon in the vacuum environment, applied study of the potential for GPFUTV to be developed for deep seawater suction technology and lifting technology for deep ocean mining, theoretical study of flow stability and flow resistance under GPFUTV condition, etc. At last, the famous GPFUTV project is illustrated. 12 years of rigorous and independent survey research.

A case study of the Secure Anonymous Information Linkage (SAIL) Gateway: A privacy-protecting remote access system for health-related research and evaluation☆

PubMed Central

Jones, Kerina H.; Ford, David V.; Jones, Chris; Dsilva, Rohan; Thompson, Simon; Brooks, Caroline J.; Heaven, Martin L.; Thayer, Daniel S.; McNerney, Cynthia L.; Lyons, Ronan A.

2014-01-01

With the current expansion of data linkage research, the challenge is to find the balance between preserving the privacy of person-level data whilst making these data accessible for use to their full potential. We describe a privacy-protecting safe haven and secure remote access system, referred to as the Secure Anonymised Information Linkage (SAIL) Gateway. The Gateway provides data users with a familiar Windows interface and their usual toolsets to access approved anonymously-linked datasets for research and evaluation. We outline the principles and operating model of the Gateway, the features provided to users within the secure environment, and how we are approaching the challenges of making data safely accessible to increasing numbers of research users. The Gateway represents a powerful analytical environment and has been designed to be scalable and adaptable to meet the needs of the rapidly growing data linkage community. PMID:24440148

Energetics and solvation structure of a dihalogen dopant (I2) in (4)He clusters.

PubMed

Pérez de Tudela, Ricardo; Barragán, Patricia; Valdés, Álvaro; Prosmiti, Rita

2014-08-21

The energetics and structure of small HeNI2 clusters are analyzed as the size of the system changes, with N up to 38. The full interaction between the I2 molecule and the He atoms is based on analytical ab initio He-I2 potentials plus the He-He interaction, obtained from first-principle calculations. The most stable structures, as a function of the number of solvent He atoms, are obtained by employing an evolutionary algorithm and compared with CCSD(T) and MP2 ab initio computations. Further, the classical description is completed by explicitly including thermal corrections and quantum features, such as zero-point-energy values and spatial delocalization. From quantum PIMC calculations, the binding energies and radial/angular probability density distributions of the thermal equilibrium state for selected-size clusters are computed at a low temperature. The sequential formation of regular shell structures is analyzed and discussed for both classical and quantum treatments.

Electronic structure and optical properties of iron based chalcogenide FeX2 (X = S, Se, Te) for photovoltaic applications: a first principle study

NASA Astrophysics Data System (ADS)

Ghosh, Anima; Thangavel, R.

2017-11-01

In present work, the electronic structure and optical properties of the FeX2 (X = S, Se, Te) compounds have been evaluated by the density functional theory based on the scalar-relativistic full potential linear augmented plane wave method via Wien2K. From the total energy calculations, it has been found that all the compounds have direct band nature, which determined by iron 3 d states at valance band edge and anion p dominated at conduction band at Γ-point and the fundamental band gap between the valence band and conduction band are estimated 1.40, 1.02 and 0.88 eV respectively with scissor correction for FeS2, FeSe2 and FeTe2 which are close to the experimental values. The optical properties such as dielectric tensor components and the absorption coefficient of these materials are determined in order to investigate their usefulness in photovoltaic applications.

Sparse Reconstruction Techniques in MRI: Methods, Applications, and Challenges to Clinical Adoption

PubMed Central

Yang, Alice Chieh-Yu; Kretzler, Madison; Sudarski, Sonja; Gulani, Vikas; Seiberlich, Nicole

2016-01-01

The family of sparse reconstruction techniques, including the recently introduced compressed sensing framework, has been extensively explored to reduce scan times in Magnetic Resonance Imaging (MRI). While there are many different methods that fall under the general umbrella of sparse reconstructions, they all rely on the idea that a priori information about the sparsity of MR images can be employed to reconstruct full images from undersampled data. This review describes the basic ideas behind sparse reconstruction techniques, how they could be applied to improve MR imaging, and the open challenges to their general adoption in a clinical setting. The fundamental principles underlying different classes of sparse reconstructions techniques are examined, and the requirements that each make on the undersampled data outlined. Applications that could potentially benefit from the accelerations that sparse reconstructions could provide are described, and clinical studies using sparse reconstructions reviewed. Lastly, technical and clinical challenges to widespread implementation of sparse reconstruction techniques, including optimization, reconstruction times, artifact appearance, and comparison with current gold-standards, are discussed. PMID:27003227

Searching for beauty-fully bound tetraquarks using lattice nonrelativistic QCD

DOE PAGES

Hughes, Ciaran; Eichten, Estia; Davies, Christine T. H.

2018-03-14

Motivated by multiple phenomenological considerations, we perform the first search for the existence of amore » $$\\bar{bb}bb$$ tetraquark bound state with a mass below the lowest noninteracting bottomonium-pair threshold using the first-principles lattice nonrelativistic QCD methodology. Here, we use a full S-wave color/spin basis for the $$\\bar{bb}bb$$ operators in the three 0 ++, 1 +- and 2 ++ channels. We employ four gluon field ensembles at multiple lattice spacing values ranging from a=0.06–0.12 fm, all of which include u, d, s and c quarks in the sea, and one ensemble which has physical light-quark masses. Additionally, we perform novel exploratory work with the objective of highlighting any signal of a near threshold tetraquark, if it existed, by adding an auxiliary potential into the QCD interactions. With our results we find no evidence of a QCD bound tetraquark below the lowest noninteracting thresholds in the channels studied.« less

Quasielastic small-angle neutron scattering from heavy water solutions of cyclodextrins

NASA Astrophysics Data System (ADS)

Kusmin, André; Lechner, Ruep E.; Saenger, Wolfram

2011-01-01

We present a model for quasielastic neutron scattering (QENS) by an aqueous solution of compact and inflexible molecules. This model accounts for time-dependent spatial pair correlations between the atoms of the same as well as of distinct molecules and includes all coherent and incoherent neutron scattering contributions. The extension of the static theory of the excluded volume effect [A. K. Soper, J. Phys.: Condens. Matter 9, 2399 (1997)] to the time-dependent (dynamic) case allows us to obtain simplified model expressions for QENS spectra in the low Q region in the uniform fluid approximation. The resulting expressions describe the quasielastic small-angle neutron scattering (QESANS) spectra of D _2O solutions of native and methylated cyclodextrins well, yielding in particular translational and rotational diffusion coefficients of these compounds in aqueous solution. Finally, we discuss the full potential of the QESANS analysis (that is, beyond the uniform fluid approximation), in particular, the information on solute-solvent interactions (e.g., hydration shell properties) that such an analysis can provide, in principle.

A framework for the comparative study of language.

PubMed

Uriagereka, Juan; Reggia, James A; Wilkinson, Gerald S

2013-07-18

Comparative studies of language are difficult because few language precursors are recognized. In this paper we propose a framework for designing experiments that test for structural and semantic patterns indicative of simple or complex grammars as originally described by Chomsky. We argue that a key issue is whether animals can recognize full recursion, which is the hallmark of context-free grammar. We discuss limitations of recent experiments that have attempted to address this issue, and point out that experiments aimed at detecting patterns that follow a Fibonacci series have advantages over other artificial context-free grammars. We also argue that experiments using complex sequences of behaviors could, in principle, provide evidence for fully recursive thought. Some of these ideas could also be approached using artificial life simulations, which have the potential to reveal the types of evolutionary transitions that could occur over time. Because the framework we propose has specific memory and computational requirements, future experiments could target candidate genes with the goal of revealing the genetic underpinnings of complex cognition.

[Theoretical risk management and legitimacy of the precautionary principle in medicine. Look back at HIV contamination through blood transfusion in France, twenty years ago].

PubMed

Moutel, G; Hergon, E; Duchange, N; Bellier, L; Rouger, P; Hervé, C

2005-02-01

The precautionary principle first appeared in France during the health crisis following the contamination of patients with HIV via blood transfusion. This study analyses whether the risk associated with blood transfusion was taken into account early enough considering the context of scientific uncertainty between 1982 and 1985. The aim was to evaluate whether a precautionary principle was applied and whether it was relevant. First, we investigated the context of scientific uncertainty and controversies prevailing between 1982 and 1985. Then we analysed the attitude and decisions of the French authorities in this situation to determine whether a principle of precaution was applied. Finally, we explored the reasons at the origin of the delay in controlling the risk. Despite the scientific uncertainties associated with the potential risk of HIV contamination by transfusion in 1983, we found that a list of recommendations aiming to reduce this risk was published in June of that year. In the prevailing climate of uncertainty, these measures could be seen as precautionary. However, the recommended measures were not widely applied. Cultural, structural and economic factors hindered their implementation. Our analysis provides insight into the use of precautionary principle in the domain of blood transfusion and, more generally, medicine. It also sheds light on the expectations that health professionals should have of this principle. The aim of the precautionary principle is to manage rather than to reduce scientific uncertainty. The principle is not a futile search for zero risk. Rather, it is a principle for action allowing precautionary measures to be taken. However, we show that these measures must appear legitimate to be applied. This legitimacy requires an adapted decision-making process, involving all those concerned in the management of collective risks.

Plasticity during Early Brain Development Is Determined by Ontogenetic Potential.

PubMed

Krägeloh-Mann, Ingeborg; Lidzba, Karen; Pavlova, Marina A; Wilke, Marko; Staudt, Martin

2017-04-01

Two competing hypotheses address neuroplasticity during early brain development: the "Kennard principle" describes the compensatory capacities of the immature developing CNS as superior to those of the adult brain, whereas the "Hebb principle" argues that the young brain is especially sensitive to insults. We provide evidence that these principles are not mutually exclusive. Following early brain lesions that are unilateral, the brain can refer to homotopic areas of the healthy hemisphere. This potential for reorganization is unique to the young brain but available only when, during ontogenesis of brain development, these areas have been used for the functions addressed. With respect to motor function, ipsilateral motor tracts can be recruited, which are only available during early brain development. Language can be reorganized to the right after early left hemispheric lesions, as the representation of the language network is initially bilateral. However, even in these situations, compensatory capacities of the developing brain are found to have limitations, probably defined by early determinants. Thus, plasticity and adaptivity are seen only within ontogenetic potential; that is, axonal or cortical structures cannot be recruited beyond early developmental possibilities. The young brain is probably more sensitive and vulnerable to lesions when these are bilateral. This is shown here for bilateral periventricular white matter lesions that clearly have an impact on cortical architecture and function, thus probably interfering with early network building. Georg Thieme Verlag KG Stuttgart · New York.

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

Morris, J.R.; Lu, Z.; Ring, D.M.

We have examined a variety of structures for the {l_brace}510{r_brace} symmetric tilt boundary in Si and Ge, using tight-binding and first-principles calculations. These calculations show that the observed structure in Si is the lowest-energy structure, despite the fact that it is more complicated than what is necessary to preserve fourfold coordination. Contrary to calculations using a Tersoff potential, first-principles calculations show that the energy depends strongly upon the structure. A recently developed tight-binding model for Si produces results in very good agreement with the first-principles calculations. Electronic density of states calculations based upon this model show no evidence of midgapmore » states and little evidence of electronic states localized to the grain boundary. {copyright} {ital 1998} {ital The American Physical Society}« less

Treatment principles for the management of mold infections.

PubMed

Kontoyiannis, Dimitrios P; Lewis, Russell E

2014-11-06

Survival rates among immunocompromised patients with invasive mold infections have markedly improved over the last decade with earlier diagnosis and new antifungal treatment options. Yet, increasing antifungal resistance, breakthrough infections with intrinsically resistant fungi, and potentially life-threatening adverse effects and drug interactions are becoming more problematic, especially with prolonged therapy. Evidence-based recommendations for treating invasive aspergillosis and mucormycosis provide excellent guidance on the initial workup and treatment of these molds, but they cannot address all of the key management issues. Herein, we discuss 10 general treatment principles in the management of invasive mold disease in immunocompromised patients and discuss how these principles can be integrated to develop an effective, individualized treatment plan. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

[Application criteria of the precautionary principle].

PubMed

Moccaldi, R

2011-01-01

The precautionary principle, according to the European Commission (February 2, 2000) must be applied when there is a possibility of a danger to humans, animals and/or environment health, i.e. when the potential harmful effects have been identified by a scientific and objective evaluation, but this evaluation does not allow the risk to be determined with sufficient certainty. However this principle has been invoked, without the identification, even partial, of harmful effects, to justify preventive and protective measures deemed necessary by policy maker mainly due to a high (but unjustified) risk perception by the population. We analyze the examples of the limits imposed by Italian legislation for the protection from EMF, and measures of "prudent avoidance" in the use of mobile phones.

Synergetics of hardening construction systems

NASA Astrophysics Data System (ADS)

Tolstoy, A. D.; Lesovik, V. S.; Glagolev, E. S.; Krymova, A. I.

2018-03-01

The study of hardening high-strength systems indicates the relation between the potential of synergetics and issues related to structure formation of aggregates produced on the basis of rationally selected construction mixes. The paper considers challenges of the general principles of synergetics and sustainable development of open dissipative systems and their use in industry, as well as their understanding as complete self-regulating nonequilibrium systems. The main objective of the study was to demonstrate that the principles of self-regulating systems development can be applied in construction technology.

Study of the extra-ionic electron distributions in semi-metallic structures by nuclear quadrupole resonance techniques

NASA Technical Reports Server (NTRS)

Murty, A. N.

1976-01-01

A straightforward self-consistent method was developed to estimate solid state electrostatic potentials, fields and field gradients in ionic solids. The method is a direct practical application of basic electrostatics to solid state and also helps in the understanding of the principles of crystal structure. The necessary mathematical equations, derived from first principles, were presented and the systematic computational procedure developed to arrive at the solid state electrostatic field gradients values was given.

The Impact of Maintenance Free Operating Period Approach to Acquisition Approaches, System Sustainment, and Costs

DTIC Science & Technology

2013-01-07

of MFOP principles on processes, procedures , and costs in acquisition planning. It investigates MFOP and reviews the results of a 2005 submarine pilot...approach be a game changer? This paper evaluates the potential impact of MFOP principles on processes, procedures , and costs in acquisition planning. It...elli=lc=_rpfkbpp=C=mr_if`=mlif`v= = - 2 - k^s^i=mlpqdo^ar^qb=p`elli= procedures , and costs in acquisition planning. The scope of the research was to

Potential contributions of hypnosis to ego-strengthening procedures in EMDR. Eye Movement Desensitization Reprocessing.

PubMed

Phillips, M

2001-01-01

This paper explores how hypnotic principles can be systematically incorporated into the standard EMDR protocol to enhance various ego strength capacities during EMDR treatment. Expanding these skill areas can widen the therapeutic window of possibility for clients with a variety of complex clinical issues, including posttraumatic, dissociative or personality disorders, anxiety symptoms, and depressive difficulties. Clinical case examples are used to illustrate ways of integrating hypnotic principles within a proposed EMDR protocol to promote ego strengthening and facilitate therapeutic change.