Introduction to the Special Section: Toward a Dimensionally Based Taxonomy of Psychopathology

PubMed Central

Krueger, Robert F.; Watson, David; Barlow, David H.

2008-01-01

Much current psychopathology research is framed by categorical constructs. Limitations of categorical constructs have been articulated, and dimensional constructs are often proposed as viable alternatives to categories of psychopathology. The purpose of this Special Section is to articulate and discuss diverse issues that arise in contemplating dimensional constructs as targets for psychopathology research. PMID:16351372

Can a rapid measure of self-exposure to drugs of abuse provide dimensional information on depression comorbidity?

PubMed

Butelman, Eduardo Roque; Bacciardi, Silvia; Maremmani, Angelo Giovanni Icro; Darst-Campbell, Maya; Correa da Rosa, Joel; Kreek, Mary Jeanne

2017-09-01

Addictions to heroin or to cocaine are associated with substantial psychiatric comorbidity, including depression. Poly-drug self-exposure (eg, to heroin, cocaine, cannabis, or alcohol) is also common, and may further affect depression comorbidity. This case-control study examined the relationship of exposure to the above drugs and depression comorbidity. Participants were recruited from methadone maintenance clinics, and from the community. Adult male and female participants (n = 1,201) were ascertained consecutively by experienced licensed clinicians. The instruments used were the SCID-I, and Kreek-McHugh-Schluger-Kellogg (KMSK) scales, which provide a rapid dimensional measure of maximal lifetime self-exposure to each of the above drugs. This measure ranges from no exposure to high unit dose, high frequency, and long duration of exposure. A multiple logistic regression with stepwise variable selection revealed that increasing exposure to heroin or to cocaine was associated greater odds of depression, with all cases and controls combined. In cases with an opioid dependence diagnosis, increasing cocaine exposure was associated with a further increase in odds of depression. However, in cases with a cocaine dependence diagnosis, increasing exposure to either cannabis or alcohol, as well as heroin, was associated with a further increase in odds of depression. This dimensional analysis of exposure to specific drugs provides insights on depression comorbidity with addictive diseases, and the impact of poly-drug exposure. A rapid analysis of exposure to drugs of abuse reveals how specific patterns of drug and poly-drug exposure are associated with increasing odds of depression. This approach detected quantitatively how different patterns of poly-drug exposure can result in increased odds of depression comorbidity, in cases diagnosed with opioid versus cocaine dependence. (Am J Addict 2017;26:632-639). © 2017 American Academy of Addiction Psychiatry.

Which Components of Medical Homes Reduce the Time Burden on Families of Children with Special Health Care Needs?

PubMed Central

Miller, Jane E; Nugent, Colleen N; Russell, Louise B

2015-01-01

Objectives To examine which components of medical homes affect time families spend arranging/coordinating health care for their children with special health care needs (CSHCNs) and providing health care at home. Data Sources 2009–2010 National Survey of Children with Special Health Care Needs (NS-CSHCN), a population-based survey of 40,242 CSHCNs. Study Design NS-CSHCN is a cross-sectional, observational study. We used generalized ordered logistic regression, testing for nonproportional odds in the associations between each of five medical home components and time burden, controlling for insurance, child health, and sociodemographics. Data Collection/Extraction Methods Medical home components were collected using Child and Adolescent Health Measurement Initiative definitions. Principal Findings Family-centered care, care coordination, and obtaining needed referrals were associated with 15–32 percent lower odds of time burdens arranging/coordinating and 16–19 percent lower odds providing health care. All five components together were associated with lower odds of time burdens, with greater reductions for higher burdens providing care. Conclusions Three of the five medical home components were associated with lower family time burdens arranging/coordinating and providing health care for children with chronic conditions. If the 55 percent of CSHCNs lacking medical homes had one, the share of families with time burdens arranging care could be reduced by 13 percent. PMID:25100200

Limited access to special education services for school-aged children with developmental delay.

PubMed

Twardzik, Erica; Smit, Ellen; Hatfield, Bridget; Odden, Michelle C; Dixon-Ibarra, Alicia; MacDonald, Megan

2018-01-01

Current policy in Oregon limits eligibility of children diagnosed with developmental delay for school-based services. Due to eligibility definitions, children with developmental delay may face additional barriers transitioning from early intervention/early childhood special education into school-based special education services. Examine the relationship between enrollment in school-based special education programs given a change in primary disability diagnosis. Logistic regression models were fit for children who enrolled in early intervention/early childhood special education services with a primary disability diagnosis of developmental delay and changed primary disability diagnosis before third grade (n=5076). Odds of enrollment in future special education were greater in children with a change in primary disability diagnosis after the age of five in comparison to children that had a change in primary disability diagnosis before the age of five, while adjusting for demographic characteristics (adjusted odds ratio: 2.37, 95% CI 1.92, 2.92). Results suggest that children who are diagnosed with a developmental delay and exit early childhood special education due to maximum age of eligibility are more likely to enroll in special education compared to children without a gap in service access. Gaps in service access during early development are associated with the need for supportive services later on in life. Copyright © 2017 Elsevier Ltd. All rights reserved.

A deformation of Sasakian structure in the presence of torsion and supergravity solutions

NASA Astrophysics Data System (ADS)

Houri, Tsuyoshi; Takeuchi, Hiroshi; Yasui, Yukinori

2013-07-01

A deformation of Sasakian structure in the presence of totally skew-symmetric torsion is discussed on odd-dimensional manifolds whose metric cones are Kähler with torsion. It is shown that such a geometry inherits similar properties to those of Sasakian geometry. As their example, we present an explicit expression of local metrics. It is also demonstrated that our example of the metrics admits the existence of hidden symmetry described by non-trivial odd-rank generalized closed conformal Killing-Yano tensors. Furthermore, using these metrics as an ansatz, we construct exact solutions in five-dimensional minimal gauged/ungauged supergravity and 11-dimensional supergravity. Finally, the global structures of the solutions are discussed. We obtain regular metrics on compact manifolds in five dimensions, which give natural generalizations of Sasaki-Einstein manifolds Yp, q and La, b, c. We also briefly discuss regular metrics on non-compact manifolds in 11 dimensions.

Alpha decay hindrance factors and reflection asymmetry in nuclei

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

Sheline, R.K.; Bossinga, B.B.

1991-07-01

All available hindrance factors of alpha transitions to low-lying negative-parity states in doubly even nuclei, to odd-{ital A} parity doublets and to doubly odd parity doublet bands, are used to study the systematics of reflection asymmetry in the {ital A}{similar to}218--230 region. Special attention is given to the polarization effect of the odd particle in increasing reflection asymmetry and therefore decreasing hindrance factors to the opposite parity states of octupole bands.

Impact of neurosurgeon specialization on patient outcomes for intracranial and spinal surgery: a retrospective analysis of the Nationwide Inpatient Sample 1998-2009.

PubMed

McCutcheon, Brandon A; Hirshman, Brian R; Gabel, Brandon C; Heffner, Michael W; Marcus, Logan P; Cole, Tyler S; Chen, Clark C; Chang, David C; Carter, Bob S

2018-05-01

OBJECTIVE The subspecialization of neurosurgical practice is an ongoing trend in modern neurosurgery. However, it remains unclear whether the degree of surgeon specialization is associated with improved patient outcomes. The authors hypothesized that a trend toward increased neurosurgeon specialization was associated with improved patient morbidity and mortality rates. METHODS The Nationwide Inpatient Sample (NIS) was used (1998-2009). Patients were included in a spinal analysis cohort for instrumented spine surgery involving the cervical spine ( International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes 81.31-81.33, 81.01-81.03, 84.61-84.62, and 84.66) or lumbar spine (codes 81.04-81.08, 81.34-81.38, 84.64-84.65, and 84.68). A cranial analysis cohort consisted of patients receiving a parenchymal excision or lobectomy operation (codes 01.53 and 01.59). Surgeon specialization was measured using unique surgeon identifiers in the NIS and defined as the proportion of a surgeon's total practice dedicated to cranial or spinal cases. RESULTS A total of 46,029 and 231,875 patients were identified in the cranial and spinal analysis cohorts, respectively. On multivariate analysis in the cranial analysis cohort (after controlling for overall surgeon volume, patient demographic data/comorbidities, hospital characteristics, and admitting source), each percentage-point increase in a surgeon's cranial specialization (that is, the proportion of cranial cases) was associated with a 0.0060 reduction in the log odds of patient mortality (95% CI 0.0034-0.0086) and a 0.0042 reduction in the log odds of morbidity (95% CI 0.0032-0.0052). This resulted in a 15% difference in the predicted probability of mortality for neurosurgeons at the 75th versus the 25th percentile of cranial specialization. In the spinal analysis cohort, each percentage-point increase in a surgeon's spinal specialization was associated with a 0.0122 reduction in the log odds of mortality (95% CI 0.0074-0.0170) and a 0.0058 reduction in the log odds of morbidity (95% CI 0.0049-0.0067). This resulted in a 26.8% difference in the predicted probability of mortality for neurosurgeons at the 75th versus the 25th percentile of spinal specialization. CONCLUSIONS For both spinal and cranial surgery patient cohorts derived from the NIS database, increased surgeon specialization was significantly and independently associated with improved mortality and morbidity rates, even after controlling for overall case volume.

Analytic Wave Functions for the Half-Filled Lowest Landau Level

NASA Astrophysics Data System (ADS)

Ciftja, Orion

We consider a two-dimensional strongly correlated electronic system in a strong perpendicular magnetic field at half-filling of the lowest Landau level (LLL). We seek to build a wave function that, by construction, lies entirely in the Hilbert space of the LLL. Quite generally, a wave function of this nature can be built as a linear combination of all possible Slater determinants formed by using the complete set of single-electron states that belong to the LLL. However, due to the vast number of Slater determinant states required to form such basis functions, the expansion is impractical for any but the smallest systems. Thus, in practice, the expansion must be truncated to a small number of Slater determinants. Among many possible LLL Slater determinant states, we note a particular special class of such wave functions in which electrons occupy either only even, or only odd angular momentum states. We focus on such a class of wave functions and obtain analytic expressions for various quantities of interest. Results seem to suggest that these special wave functions, while interesting and physically appealing, are unlikely to be a very good approximation for the exact ground state at half-filling factor. The overall quality of the description can be improved by including other additional LLL Slater determinant states. It is during this process that we identify another special family of suitable LLL Slater determinant states to be used in an enlarged expansion.

Modulated Structures of Homologous Compounds In MO 3(ZnO) m( M=In, Ga; m=Integer) Described by Four-Dimensional Superspace Group

NASA Astrophysics Data System (ADS)

Li, Chunfei; Bando, Yoshio; Nakamura, Masaki; Onoda, Mitsuko; Kimizuka, Noboru

1998-09-01

The modulated structures appearing in the homologous compounds InMO3(ZnO)m(M=In, Ga;m=integer) were observed by using a high-resoultion transmission electron microscope and are described based on a four-dimensional superspace group. The electron diffraction patterns for compounds withmlarger than 6 reveal extra spots, indicating the formation of a modulated structure. The subcell structures form=odd and even numbers are assigned to be either monoclinic or orthorhombic, respectively. On the other hand, extra spots can be indexed by one-dimensional modulated structure. The possible space groups for the subcell structure areCm,C2, andC2/mform=odd numbers, while those form=even numbers areCcm21andCcmm, respectively. Then, corresponding possible superspace groups are assigned to bePC2s,PCmoverline1, andPC2/msoverline1for oddmnumbers andPCcm211overline1overline1andPCcmm1overline11for evenmnumbers. Based on the superspace group determination, a structure model for a one-dimensional modulated structure is proposed.

Care coordination, the family-centered medical home, and functional disability among children with special health care needs.

PubMed

Litt, Jonathan S; McCormick, Marie C

2015-01-01

Children with special health care needs (CSHCN) are at increased risk for functional disabilities. Care coordination has been shown to decrease unmet health service use but has yet been shown to improve functional status. We hypothesize that care coordination services lower the odds of functional disability for CSHCN and that this effect is greater within the context of a family-centered medical home. A secondary objective was to test the mediating effect of unmet care needs on functional disability. Our sample included children ages 0 to 17 years participating the 2009-2010 National Survey of Children with Special Health Care Needs. Care coordination, unmet needs, and disability were measured by parent report. We used logistic regression models with covariate adjustment for confounding and a mediation analysis approach for binary outcomes to assess the effect of unmet needs. There were 34,459 children in our sample. Care coordination was associated with lower odds of having a functional disability (adjusted odds ratio 0.82, 95% confidence interval 0.77, 0.88). This effect was greater for care coordination in the context of a medical home (adjusted odds ratio 0.71, 95% confidence interval 0.66, 0.76). The relationship between care coordination and functional disability was mediated by reducing unmet services. Care coordination is associated with lower odds of functional disability among CSHCN, especially when delivered in the setting of a family-centered medical home. Reducing unmet service needs mediates this effect. Our findings support a central role for coordination services in improving outcomes for vulnerable children. Copyright © 2015 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

General flat four-dimensional world pictures and clock systems

NASA Technical Reports Server (NTRS)

Hsu, J. P.; Underwood, J. A.

1978-01-01

We explore the mathematical structure and the physical implications of a general four-dimensional symmetry framework which is consistent with the Poincare-Einstein principle of relativity for physical laws and with experiments. In particular, we discuss a four-dimensional framework in which all observers in different frames use one and the same grid of clocks. The general framework includes special relativity and a recently proposed new four-dimensional symmetry with a nonuniversal light speed as two special simple cases. The connection between the properties of light propagation and the convention concerning clock systems is also discussed, and is seen to be nonunique within the four-dimensional framework.

Comparison of model results transporting the odd nitrogen family with results transporting separate odd nitrogen species

NASA Technical Reports Server (NTRS)

Douglass, Anne R.; Jackman, Charles H.; Stolarski, Richard S.

1989-01-01

A fast two-dimensional residual circulation stratospheric family transport model, designed to minimize computer requirements, is developed. The model was used to calculate the ambient and perturbed atmospheres in which odd nitrogen species are transported as a family, and the results were compared with calculations in which HNO3, N2O5, ClONO2, and HO2NO2 are transported separately. It was found that ozone distributions computed by the two models for a present-day atmosphere are nearly identical. Good agreement was also found between calculated species concentrations and the ozone response, indicating the general applicability of the odd-nitrogen family approximations.

Effect of solar proton events in 1978 and 1979 on the odd nitrogen abundance in the middle atmosphere

NASA Technical Reports Server (NTRS)

Jackman, Charles H.; Meade, Paul E.

1988-01-01

Daily average solar proton flux data for 1978 and 1979 are used in a proton energy degradation scheme to derive ion pair production rates and atomic nitrogen production rates. The latter are computed in a form suitable for inclusion in an atmopheric, two-dimensional, time-dependent photochemical model. Odd nitrogen distributions are computed from the model, including atomic nitrogen production from solar protons, and are compared with baseline distributions. The comparisons show that the average effect of the solar protons in 1978 and 1979 was to cause changes in odd nitrogen only above 10 mbar and at latitudes only above about 50 deg in both hemispheres. The influence of the solar proton-produced odd nitrogen on the local abundance of odd nitrogen depends primarily on the background odd nitrogen abundance as well as the altitude and season.

Placental three-dimensional power Doppler indices in mid-pregnancy and late pregnancy complicated by gestational diabetes mellitus.

PubMed

Surányi, A; Kozinszky, Z; Molnár, A; Nyári, T; Bitó, T; Pál, A

2013-10-01

The aim of our study was to evaluate placental three-dimensional power Doppler indices in diabetic pregnancies in the second and third trimesters and to compare them with those of the normal controls. Placental vascularization of pregnant women was determined by three-dimensional power Doppler ultrasound technique. The calculated indices included vascularization index (VI), flow index (FI), and vascularization flow index (VFI). Uncomplicated pregnancies (n = 113) were compared with pregnancies complicated by gestational diabetes mellitus (n = 56) and diabetes mellitus (n = 43). The three-dimensional power Doppler indices were not significantly different between the two diabetic subgroups. All the indices in diabetic patients were significantly reduced compared with those in non-diabetic individuals (p < 0.001). Placental three-dimensional power Doppler indices are slightly diminished throughout diabetic pregnancy [regression coefficients: -0.23 (FI), -0.06 (VI), and -0.04 (VFI)] and normal pregnancy [regression coefficients: -0.13 (FI), -0.20 (VI), and -0.11 (VFI)]. The uteroplacental circulation (umbilical and uterine artery) was not correlated significantly to the three-dimensional power Doppler indices. If all placental indices are low during late pregnancy, then the odds of the diabetes are significantly high (adjusted odds ratio: 1.10). A decreased placental vascularization could be an adjunct sonographic marker in the diagnosis of diabetic pregnancy in mid-gestation and late gestation. © 2013 John Wiley & Sons, Ltd.

Parsing the Relations of Race and Socioeconomic Status in Special Education Disproportionality

ERIC Educational Resources Information Center

Kincaid, Aleksis P.; Sullivan, Amanda L.

2017-01-01

This study investigated how student and school-level socioeconomic status (SES) measures predict students' odds of being identified for special education, particularly high-incidence disabilities. Using the Early Childhood Longitudinal Study--Kindergarten cohort, hierarchical models were used to determine the relations of student and school SES to…

Implementing odd-axions in dimensional oxidation of 4D non-geometric type IIB scalar potential

NASA Astrophysics Data System (ADS)

Shukla, Pramod

2016-01-01

In a setup of type IIB superstring compactification on an orientifold of a T6 /Z4 sixfold, the presence of geometric flux (ω) and non-geometric fluxes (Q, R) is implemented along with the standard NS-NS and RR three-form fluxes (H, F). After computing the F/D-term contributions to the N = 1 four dimensional effective scalar potential, we rearrange the same into 'suitable' pieces by using a set of new generalized flux orbits. Subsequently, we dimensionally oxidize the various pieces of the total four dimensional scalar potential to guess their ten-dimensional origin.

Quaternionic (super) twistors extensions and general superspaces

NASA Astrophysics Data System (ADS)

Cirilo-Lombardo, Diego Julio; Pervushin, Victor N.

2017-09-01

In a attempt to treat a supergravity as a tensor representation, the four-dimensional N-extended quaternionic superspaces are constructed from the (diffeomorphyc) graded extension of the ordinary Penrose-twistor formulation, performed in a previous work of the authors [D. J. Cirilo-Lombardo and V. N. Pervushin, Int. J. Geom. Methods Mod. Phys., doi: http://dx.doi.org/10.1142/S0219887816501139.], with N = p + k. These quaternionic superspaces have 4 + k(N - k) even-quaternionic coordinates and 4N odd-quaternionic coordinates, where each coordinate is a quaternion composed by four ℂ-fields (bosons and fermions respectively). The fields content as the dimensionality (even and odd sectors) of these superspaces are given and exemplified by selected physical cases. In this case, the number of fields of the supergravity is determined by the number of components of the tensor representation of the four-dimensional N-extended quaternionic superspaces. The role of tensorial central charges for any N even USp(N) = Sp(N, ℍℂ) ∩ U(N, ℍℂ) is elucidated from this theoretical context.

Three-dimensional imaging of the craniofacial complex.

PubMed

Nguyen, Can X.; Nissanov, Jonathan; Öztürk, Cengizhan; Nuveen, Michiel J.; Tuncay, Orhan C.

2000-02-01

Orthodontic treatment requires the rearrangement of craniofacial complex elements in three planes of space, but oddly the diagnosis is done with two-dimensional images. Here we report on a three-dimensional (3D) imaging system that employs the stereoimaging method of structured light to capture the facial image. The images can be subsequently integrated with 3D cephalometric tracings derived from lateral and PA films (www.clinorthodres.com/cor-c-070). The accuracy of the reconstruction obtained with this inexpensive system is about 400 µ.

Three-dimensional structural analysis using interactive graphics

NASA Technical Reports Server (NTRS)

Biffle, J.; Sumlin, H. A.

1975-01-01

The application of computer interactive graphics to three-dimensional structural analysis was described, with emphasis on the following aspects: (1) structural analysis, and (2) generation and checking of input data and examination of the large volume of output data (stresses, displacements, velocities, accelerations). Handling of three-dimensional input processing with a special MESH3D computer program was explained. Similarly, a special code PLTZ may be used to perform all the needed tasks for output processing from a finite element code. Examples were illustrated.

Three-dimensional simulation of free-electron laser harmonics with FRED

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

Sharp, W.M.; Scharlemann, E.T.; Fawley, W.M.

1989-11-20

FRED3D, a single-mode three-dimensional version of the FEL simulation code FRED, has been modified to follow the growth of signal components at the fundamental frequency and at even and odd harmonics. The Wiggle-averaged particle and field equations for this multi-mode formulation are derived here, and their implementation in FRED3D is discussed. 12 refs.

Functional diversity of 2-oxoglutarate/Fe(II)-dependent dioxygenases in plant metabolism

PubMed Central

Farrow, Scott C.; Facchini, Peter J.

2014-01-01

Oxidative enzymes catalyze many different reactions in plant metabolism. Among this suite of enzymes are the 2-oxoglutarate/Fe(II)-dependent dioxygenases (2-ODDs). Cytochromes P450 (CYPs) as often considered the most versatile oxidative enzymes in nature, but the diversity and complexity of reactions catalyzed by 2-ODDs is superior to the CYPs. The list of oxidative reactions catalyzed by 2-ODDs includes hydroxylations, demethylations, desaturations, ring closure, ring cleavage, epimerization, rearrangement, halogenation, and demethylenation. Furthermore, recent work, including the discovery of 2-ODDs involved in epigenetic regulation, and others catalyzing several characteristic steps in specialized metabolic pathways, support the argument that 2-ODDs are among the most versatile and important oxidizing biological catalysts. In this review, we survey and summarize the pertinent literature with a focus on several key reactions catalyzed by 2-ODDs, and discuss the significance and impact of these enzymes in plant metabolism. PMID:25346740

Cubic interactions of massless bosonic fields in three dimensions. II. Parity-odd and Chern-Simons vertices

NASA Astrophysics Data System (ADS)

Kessel, Pan; Mkrtchyan, Karapet

2018-05-01

This work completes the classification of the cubic vertices for arbitrary-spin massless bosons in three dimensions started in a previous companion paper by constructing parity-odd vertices. Similarly to the parity-even case, there is a unique parity-odd vertex for any given triple s1≥s2≥s3≥2 of massless bosons if the triangle inequalities are satisfied (s1

Atmospheric Ionization by Solar Particles Detected by Nitrate Measurements in Antarctic Snow. FY91 AASERT

NASA Technical Reports Server (NTRS)

Vitt, Francis M.; Jackman, Charles H.

1995-01-01

The odd nitrogen source strengths associated with Solar Proton Events (SPEs), Galactic Cosmic Rays (GCRs), and the oxidation of nitrous oxide in the Earth's middle atmosphere from 1974 through 1993 have been compared globally, at middle and lower latitudes (less than 50 deg), and polar regions (greater than 50 deg) with a two-dimensional (2-D) photochemical transport model. As discovered previously, the oxidation of nitrous oxide dominates the global odd nitrogen source while GCRs and SPEs are significant at polar latitudes. The horizontal transport of odd nitrogen, produced by the oxidation of nitrous oxide at latitudes < 50 deg, was found to be the dominant source of odd nitrogen in the polar regions with GCRs contributing substantially during the entire solar cycle. The source of odd nitrogen from SPEs was more sporadic; however, contributions during several years (mostly near solar maximum) were significant in the polar middle atmosphere.

Deterministic entanglement of superconducting qubits by parity measurement and feedback.

PubMed

Ristè, D; Dukalski, M; Watson, C A; de Lange, G; Tiggelman, M J; Blanter, Ya M; Lehnert, K W; Schouten, R N; DiCarlo, L

2013-10-17

The stochastic evolution of quantum systems during measurement is arguably the most enigmatic feature of quantum mechanics. Measuring a quantum system typically steers it towards a classical state, destroying the coherence of an initial quantum superposition and the entanglement with other quantum systems. Remarkably, the measurement of a shared property between non-interacting quantum systems can generate entanglement, starting from an uncorrelated state. Of special interest in quantum computing is the parity measurement, which projects the state of multiple qubits (quantum bits) to a state with an even or odd number of excited qubits. A parity meter must discern the two qubit-excitation parities with high fidelity while preserving coherence between same-parity states. Despite numerous proposals for atomic, semiconducting and superconducting qubits, realizing a parity meter that creates entanglement for both even and odd measurement results has remained an outstanding challenge. Here we perform a time-resolved, continuous parity measurement of two superconducting qubits using the cavity in a three-dimensional circuit quantum electrodynamics architecture and phase-sensitive parametric amplification. Using postselection, we produce entanglement by parity measurement reaching 88 per cent fidelity to the closest Bell state. Incorporating the parity meter in a feedback-control loop, we transform the entanglement generation from probabilistic to fully deterministic, achieving 66 per cent fidelity to a target Bell state on demand. These realizations of a parity meter and a feedback-enabled deterministic measurement protocol provide key ingredients for active quantum error correction in the solid state.

Education level and inequalities in stroke reperfusion therapy: observations in the Swedish stroke register.

PubMed

Stecksén, Anna; Glader, Eva-Lotta; Asplund, Kjell; Norrving, Bo; Eriksson, Marie

2014-09-01

Previous studies have revealed inequalities in stroke treatment based on demographics, hospital type, and region. We used the Swedish Stroke Register (Riksstroke) to test whether patient education level is associated with reperfusion (either or both of thrombolysis and thrombectomy) treatment. We included 85 885 patients with ischemic stroke aged 18 to 80 years registered in Riksstroke between 2003 and 2009. Education level was retrieved from Statistics Sweden, and thrombolysis, thrombectomy, patient, and hospital data were obtained from Riksstroke. We used multivariable logistic regression to analyze the association between reperfusion therapy and patient education. A total of 3649 (4.2%) of the patients received reperfusion therapy. University-educated patients were more likely to be treated (5.5%) than patients with secondary (4.6%) or primary education (3.6%; P<0.001). The inequality associated with education was still present after adjustment for patient characteristics; university education odds ratio, 1.14; 95% confidence interval, 1.03 to 1.26 and secondary education odds ratio, 1.08; 95% confidence interval, 1.00 to 1.17 compared with primary education. Higher hospital specialization level was also associated with higher reperfusion levels (P<0.001). In stratified multivariable analyses by hospital type, significant treatment differences by education level existed only among large nonuniversity hospitals (university education odds ratio, 1.20; 95% confidence interval, 1.04-1.40; secondary education odds ratio, 1.14; 95% confidence interval, 1.01-1.29). We demonstrated a social stratification in reperfusion, partly explained by patient characteristics and the local hospital specialization level. Further studies should address treatment delays, stroke knowledge, and means to improve reperfusion implementation in less specialized hospitals. © 2014 American Heart Association, Inc.

Higher dimensional Taub-NUT spaces and applications

NASA Astrophysics Data System (ADS)

Stelea, Cristian Ionut

In the first part of this thesis we discuss classes of new exact NUT-charged solutions in four dimensions and higher, while in the remainder of the thesis we make a study of their properties and their possible applications. Specifically, in four dimensions we construct new families of axisymmetric vacuum solutions using a solution-generating technique based on the hidden SL(2,R) symmetry of the effective action. In particular, using the Schwarzschild solution as a seed we obtain the Zipoy-Voorhees generalisation of the Taub-NUT solution and of the Eguchi-Hanson soliton. Using the C-metric as a seed, we obtain and study the accelerating versions of all the above solutions. In higher dimensions we present new classes of NUT-charged spaces, generalising the previously known even-dimensional solutions to odd and even dimensions, as well as to spaces with multiple NUT-parameters. We also find the most general form of the odd-dimensional Eguchi-Hanson solitons. We use such solutions to investigate the thermodynamic properties of NUT-charged spaces in (A)dS backgrounds. These have been shown to yield counter-examples to some of the conjectures advanced in the still elusive dS/CFT paradigm (such as the maximal mass conjecture and Bousso's entropic N-bound). One important application of NUT-charged spaces is to construct higher dimensional generalisations of Kaluza-Klein magnetic monopoles, generalising the known 5-dimensional Kaluza-Klein soliton. Another interesting application involves a study of time-dependent higher-dimensional bubbles-of-nothing generated from NUT-charged solutions. We use them to test the AdS/CFT conjecture as well as to generate, by using stringy Hopf-dualities, new interesting time-dependent solutions in string theory. Finally, we construct and study new NUT-charged solutions in higher-dimensional Einstein-Maxwell theories, generalising the known Reissner-Nordstrom solutions.

Political Specialization and Social Science Education.

ERIC Educational Resources Information Center

Miller, Jon D.

This paper outlines a two-dimensional model of political specialization and discusses its implications for social science education. The first dimension, interest specialization, involves the choice of whether or not to devote time and resources to political affairs at all. The interest specialization process of young adults and adults was…

Investigation of deformation of elements of three-dimensional reinforced concrete structures located in the soil, interacting with each other through rubber gaskets

NASA Astrophysics Data System (ADS)

Berezhnoi, D. V.; Balafendieva, I. S.; Sachenkov, A. A.; Sekaeva, L. R.

2017-06-01

In work the technique of calculation of elements of three-dimensional reinforced concrete substructures located in a soil, interacting with each other through rubber linings is realized. To describe the interaction of deformable structures with the ground, special “semi-infinite” finite elements are used. A technique has been implemented that allows one to describe the contact interaction of three-dimensional structures by means of a special contact finite element with specific properties. The obtained numerical results are compared with the experimental data, their good agreement is noted.

Higher-dimensional Bianchi type-VIh cosmologies

NASA Astrophysics Data System (ADS)

Lorenz-Petzold, D.

1985-09-01

The higher-dimensional perfect fluid equations of a generalization of the (1 + 3)-dimensional Bianchi type-VIh space-time are discussed. Bianchi type-V and Bianchi type-III space-times are also included as special cases. It is shown that the Chodos-Detweiler (1980) mechanism of cosmological dimensional-reduction is possible in these cases.

Factors Associated With Breastfeeding Duration Among Connecticut Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) Participants

PubMed Central

Haughton, Jannett; Gregorio, David; Pérez-Escamilla, Rafael

2011-01-01

This retrospective study aimed to identify factors associated with breastfeeding duration among women enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) of Hartford, Connecticut. The authors included mothers whose children were younger than 5 years and had stopped breastfeeding (N = 155). Women who had planned their pregnancies were twice as likely as those who did not plan them to breastfeed for more than 6 months (odds ratio, 2.15; 95% confidence interval, 1.00–4.64). One additional year of maternal age was associated with a 9% increase on the likelihood of breastfeeding for more than 6 months (odds ratio, 1.09; 95% confidence interval, 1.02–1.17). Time in the United States was inversely associated with the likelihood of breastfeeding for more than 6 months (odds ratio, 0.96; 95% confidence interval, 0.92–0.99). Return to work, sore nipples, lack of access to breast pumps, and free formula provided by WIC were identified as breastfeeding barriers. Findings can help WIC improve its breastfeeding promotion efforts. PMID:20689103

Surface critical behavior of thin Ising films at the ‘special point’

NASA Astrophysics Data System (ADS)

Moussa, Najem; Bekhechi, Smaine

2003-03-01

The critical surface phenomena of a magnetic thin Ising film is studied using numerical Monte-Carlo method based on Wolff cluster algorithm. With varying the surface coupling, js= Js/ J, the phase diagram exhibits a special surface coupling jsp at which all the films have a unique critical temperature Tc for an arbitrary thickness n. In spite of this, the critical exponent of the surface magnetization at the special point is found to increase with n. Moreover, non-universal features as well as dimensionality crossover from two- to three-dimensional behavior are found at this point.

Swimming at low Reynolds number in fluids with odd, or Hall, viscosity.

PubMed

Lapa, Matthew F; Hughes, Taylor L

2014-04-01

We apply the geometric theory of swimming at low Reynolds number to the study of nearly circular swimmers in two-dimensional fluids with nonvanishing "odd," or Hall, viscosity. The odd viscosity gives an off-diagonal contribution to the fluid stress tensor, which results in a number of striking effects. In particular, we find that a swimmer whose area is changing will experience a torque proportional to the rate of change of the area, with the constant of proportionality given by the coefficient ηo of odd viscosity. After working out the general theory of swimming in fluids with odd viscosity for a class of simple swimmers, we give a number of example swimming strokes which clearly demonstrate the differences between swimming in a fluid with conventional viscosity and a fluid which also has an odd viscosity. We also include a discussion of the extension of the famous Scallop theorem of low Reynolds number swimming to the case where the fluid has a nonzero odd viscosity. A number of more technical results, including a proof of the torque-area relation for swimmers of more general shape, are explained in a set of Appendixes.

Need for and use of family leave among parents of children with special health care needs.

PubMed

Chung, Paul J; Garfield, Craig F; Elliott, Marc N; Carey, Colleen; Eriksson, Carl; Schuster, Mark A

2007-05-01

Parents of children with special health care needs are especially vulnerable to work-family conflicts that family leave benefits might help resolve. We examined leave-taking among full-time-employed parents of children with special health care needs. We identified all children with special health care needs in 2 large inpatient/outpatient systems in Chicago, Illinois, and Los Angeles, California, and randomly selected 800 per site. From November 2003 to January 2004, we conducted telephone interviews with 1105 (87% of eligible and successfully contacted) parents. Among the sample's 574 full-time-employed parents, we examined whether leave benefits predicted missing any work for child illness, missing >4 weeks for child illness, and ability to miss work whenever their child needed them. Forty-eight percent of full-time-employed parents qualified for federal Family and Medical Leave Act benefits; 30% reported employer-provided leave benefits (not including sick leave/vacation). In the previous year, their children averaged 20 missed school/child care days, 12 doctor/emergency department visits, and 1.7 hospitalizations. Although 81% of parents missed work for child illness, 41% reported not always missing work when their child needed them, and 40% of leave-takers reported returning to work too soon. In multivariate regressions, parents who were eligible for Family and Medical Leave Act benefits and aware of their eligibility had 3.0 times greater odds of missing work for child illness than ineligible parents. Parents with >4 weeks of employer-provided leave benefits had 4.7 times greater odds of missing >4 weeks than parents without benefits. Parents with paid leave benefits had 2.8 times greater odds than other parents of missing work whenever their child needed them. Full-time-employed parents of children with special health care needs experience severe work-family conflicts. Although most have leave benefits, many report unmet need for leave. Access to Family and Medical Leave Act benefits and employer-provided leave may greatly affect leave-taking.

Diff-invariant kinetic terms in arbitrary dimensions

NASA Astrophysics Data System (ADS)

Barbero G., J. Fernando; Villaseñor, Eduardo J.

2002-06-01

We study the physical content of quadratic diff-invariant Lagrangians in arbitrary dimensions by using covariant symplectic techniques. This paper extends previous results in dimension four. We discuss the difference between the even and odd dimensional cases.

Unmet health care needs in children with cerebral palsy: a cross-sectional study.

PubMed

Jackson, Katie E; Krishnaswami, Shanthi; McPheeters, Melissa

2011-01-01

Children with potentially severe health conditions such as cerebral palsy (CP) are at risk for unmet health care needs. We sought to determine whether children with CP had significantly greater unmet health care needs than children with other special health care needs (SHCN), and whether conditions associated with CP increased the odds of unmet health care needs. We analyzed data from the National Survey of Children with Special Health Care Needs, 2005-2006, using multivariate logistic regression to calculate the adjusted odds of children with CP having one or more unmet health care needs compared to children with other SHCN. We also determined the association of CP-related conditions with unmet health care needs in children with CP. After weighting to national averages, our sample represented 178,536 children with CP (1.9%), and 9,236,794 with children with other SHCN (98.1%). Although having CP increased the odds that children had unmet health care needs (OR = 1.46, 95% CI [1.07-1.99]), the presence of a "severe" health condition weakened the association. Gastrointestinal problems and emotional problems increased the odds that children with CP would have unmet health care needs above that of children without the associated conditions (p ≤ .01). Children with CP are similar to children with other SHCN and may benefit from collaborative programs targeting severe chronic conditions. However, children with CP and associated conditions have increased odds of unmet health care needs in comparison to children without those problems. Copyright © 2011 Elsevier Ltd. All rights reserved.

Astronomical Odds: A Policy Framework for the Cosmic Impact Hazard

DTIC Science & Technology

2004-06-01

171. 52 An early example of an expost approach to NEO interceptor design is Project Icarus, a study effort that recommended a Saturn-V class system...68 vii viii Astronomical Odds: A Policy Framework for the Cosmic Impact Hazard 3.2. "Giggle factor" within USAF study report...the access to the NEO SDT Study model provided by MIT Lincoln Laboratory, with special thanks to Grant Stokes and Jenifer Evans. I am grateful for

The dimensionality reduction at surfaces as a playground for many-body and correlation effects

NASA Astrophysics Data System (ADS)

Tejeda, A.; Michel, E. G.; Mascaraque, A.

2013-03-01

Low-dimensional systems have always deserved attention due to the peculiarity of their physics, which is different from or even at odds with three-dimensional expectations. This is precisely the case for many-body effects, as electron-electron correlation or electron-phonon coupling are behind many intriguing problems in condensed matter physics. These interesting phenomena at low dimensions can be studied in one of the paradigms of two dimensionality—the surface of crystals. The maturity of today's surface science techniques allows us to perform thorough experimental studies that can be complemented by the current strength of state-of-the-art calculations. Surfaces are thus a natural two-dimensional playground for studying correlation and many-body effects, which is precisely the object of this special section. This special section presents a collection of eight invited articles, giving an overview of the current status of selected systems, promising techniques and theoretical approaches for studying many-body effects at surfaces and low-dimensional systems. The first article by Hofmann investigates electron-phonon coupling in quasi-free-standing graphene by decoupling graphene from two different substrates with different intercalating materials. The following article by Kirschner deals with the study of NiO films by electron pair emission, a technique particularly well-adapted for studying high electron correlation. Bovensiepen investigates electron-phonon coupling via the femtosecond time- and angle-resolved photoemission spectroscopy technique. The next article by Malterre analyses the phase diagram of alkalis on Si(111):B and studies the role of many-body physics. Biermann proposes an extended Hubbard model for the series of C, Si, Sn and Pb adatoms on Si(111) and obtains the inter-electronic interaction parameters by first principles. Continuing with the theoretical studies, Bechstedt analyses the influence of on-site electron correlation in insulating antiferromagnetic surfaces. Ortega reports on the gap of molecular layers on metal systems, where the metal-organic interaction affects the organic gap through correlation effects. Finally, Cazalilla presents a study of the phase diagram of one-dimensional atoms or molecules displaying a Kondo-exchange interaction with the substrate. Acknowledgments The editors are grateful to all the invited contributors to this special section of Journal of Physics: Condensed Matter. We also thank the IOP Publishing staff for handling the administrative matters and the refereeing process. Correlation and many-body effects at surfaces contents The dimensionality reduction at surfaces as a playground for many-body and correlation effectsA Tejeda, E G Michel and A Mascaraque Electron-phonon coupling in quasi-free-standing grapheneJens Christian Johannsen, Søren Ulstrup, Marco Bianchi, Richard Hatch, Dandan Guan, Federico Mazzola, Liv Hornekær, Felix Fromm, Christian Raidel, Thomas Seyller and Philip Hofmann Exploring highly correlated materials via electron pair emission: the case of NiO/Ag(100)F O Schumann, L Behnke, C H Li and J Kirschner Coherent excitations and electron-phonon coupling in Ba/EuFe2As2 compounds investigated by femtosecond time- and angle-resolved photoemission spectroscopyI Avigo, R Cortés, L Rettig, S Thirupathaiah, H S Jeevan, P Gegenwart, T Wolf, M Ligges, M Wolf, J Fink and U Bovensiepen Understanding the insulating nature of alkali-metal/Si(111):B interfacesY Fagot-Revurat, C Tournier-Colletta, L Chaput, A Tejeda, L Cardenas, B Kierren, D Malterre, P Le Fèvre, F Bertran and A Taleb-Ibrahimi What about U on surfaces? Extended Hubbard models for adatom systems from first principlesPhilipp Hansmann, Loïg Vaugier, Hong Jiang and Silke Biermann Influence of on-site Coulomb interaction U on properties of MnO(001)2 × 1 and NiO(001)2 × 1 surfacesA Schrön, M Granovskij and F Bechstedt On the organic energy gap problemF Flores, E Abad, J I Martínez, B Pieczyrak and J Ortega Easy-axis ferromagnetic chain on a metallic surfaceMiguel A Cazalilla

Epilepsy and Pregnancy: What You Need to Know

MedlinePlus

... Lifestyle Pregnancy week by week If you have epilepsy becoming pregnant might seem risky, but the odds ... promote a healthy pregnancy. By Mayo Clinic Staff Epilepsy during pregnancy raises special concerns. While most women ...

Rates of Complications After Newborn Circumcision in a Well-Baby Nursery, Special Care Nursery, and Neonatal Intensive Care Unit.

PubMed

Srinivasan, Mythili; Hamvas, Corrine; Coplen, Douglas

2015-10-01

To determine rates of complications after newborn circumcision by performing a retrospective chart review of patients circumcised at a well-baby nursery, neonatal intensive care units (NICU), and special care nursery (SCN) from 2007 to 2012. A total of 5129 babies (73%) were circumcised at the well-baby nursery and 1909 babies (27%) at the NICU and SCN. Forty-seven patients (0.67%, 95% CI 0.49% to 0.89%) had circumcision-related complications: 5 (0.07%) patients with acute and 42 (0.6%) with late complications. Babies in the NICU/SCN had increased odds of complication (OR 4.00, 95% CI 2.23 to 7.19) compared with those in well-baby nursery. There were increased odds of complications in babies with Caucasian ethnicity (OR 2.60, 95% CI 1.48 to 4.89) compared with African American babies and in babies with private insurance (OR 4.0, 95% CI 2.1 to 7.5) compared with nonprivate insurance. The rates of complications after newborn circumcisions were low. Babies in the NICU/SCN had increased odds of complication. © The Author(s) 2015.

The National Shipbuilding Research Program, Proceedings of the REAPS Technical Symposium Paper No. 6: SPADES System Current Developments

DTIC Science & Technology

1976-06-01

and End-Cuts Program ( PLEC ). A special program to aid in fabrication of complex three-dimensional pipe structures, which is of special interest to...LENGTH AND END-CUTS PROGRAM ( PL E C) PROGRAM DESCRIPTION 1. PROGRAM CAPABILITIES The Pipe Length and End- Cuts ( PLEC ) Development Program allows the...required categories: a. Definition Input This type of input by the ’ PLEC ’ Program can be divided in two is used to define a three-dimensional structure

Upon Generating (2+1)-dimensional Dynamical Systems

NASA Astrophysics Data System (ADS)

Zhang, Yufeng; Bai, Yang; Wu, Lixin

2016-06-01

Under the framework of the Adler-Gel'fand-Dikii(AGD) scheme, we first propose two Hamiltonian operator pairs over a noncommutative ring so that we construct a new dynamical system in 2+1 dimensions, then we get a generalized special Novikov-Veselov (NV) equation via the Manakov triple. Then with the aid of a special symmetric Lie algebra of a reductive homogeneous group G, we adopt the Tu-Andrushkiw-Huang (TAH) scheme to generate a new integrable (2+1)-dimensional dynamical system and its Hamiltonian structure, which can reduce to the well-known (2+1)-dimensional Davey-Stewartson (DS) hierarchy. Finally, we extend the binormial residue representation (briefly BRR) scheme to the super higher dimensional integrable hierarchies with the help of a super subalgebra of the super Lie algebra sl(2/1), which is also a kind of symmetric Lie algebra of the reductive homogeneous group G. As applications, we obtain a super 2+1 dimensional MKdV hierarchy which can be reduced to a super 2+1 dimensional generalized AKNS equation. Finally, we compare the advantages and the shortcomings for the three schemes to generate integrable dynamical systems.

Specialized Police-Based Mental Health Crisis Response: The First 10 Years of Colorado's Crisis Intervention Team Implementation.

PubMed

Khalsa, Hari-Mandir K; Denes, Attila C; M Pasini-Hill, Diane; Santelli, Jeffrey C; Baldessarini, Ross J

2018-02-01

This study examined the implementation of crisis intervention teams by law enforcement agencies in Colorado. Rates of Special Weapons and Tactics (SWAT) use, arrests, use of force, and injuries were assessed during 6,353 incidents involving individuals experiencing a mental health crisis. Relationships among original complaint, psychiatric illness, substance abuse, violence risk, and disposition of crisis calls were analyzed. Rates of SWAT use (<1%), injuries (<1%), arrests (<5%), and use of force (<5%) were low. The relative risk of transfer to treatment (versus no transfer) was significantly higher for incidents involving psychiatric illness, suicide threat or attempt, weapons, substance abuse, and violence potential. Use of force or SWAT, arrests, and injuries were infrequent. Suicide risk, psychiatric illness and substance abuse, even in the presence of a weapon or violence threat, increased the odds of transfer to treatment, whereas suicide risk lowered the odds of transfer to jail.

Photochemistry and dynamics of the ozone layer

NASA Technical Reports Server (NTRS)

Prinn, R. G.; Alyea, F. N.; Cunnold, D. M.

1978-01-01

The paper presents a broad review of the photochemical and dynamic theories of the ozone layer. The two theories are combined into the MIT three-dimensional dynamic-chemical quasi-geostrophic model with 26 levels in the vertical spaced in logarithmic pressure coordinates between the ground and 72-km altitude. The chemical scheme incorporates the important odd nitrogen, odd hydrogen, and odd oxygen chemistry, but is simplified in the sense that it requires specification of the distributions of NO2, OH and HO2. The prognostic equations are the vorticity equation, the perturbation thermodynamic equation, and the global mean and perturbation continuity equations for ozone; diagnostic equations include the hydrostatic equation, the balance condition, and the mass continuity equation. The model is applied to the investigation of the impact of supersonic aircraft on the ozone layer.

Generalized Gödel universes in higher dimensions and pure Lovelock gravity

NASA Astrophysics Data System (ADS)

Dadhich, Naresh; Molina, Alfred; Pons, Josep M.

2017-10-01

The Gödel universe is a homogeneous rotating dust with negative Λ which is a direct product of a three-dimensional pure rotation metric with a line. We would generalize it to higher dimensions for Einstein and pure Lovelock gravity with only one N th-order term. For higher-dimensional generalization, we have to include more rotations in the metric, and hence we shall begin with the corresponding pure rotation odd (d =2 n +1 )-dimensional metric involving n rotations, which eventually can be extended by a direct product with a line or a space of constant curvature for yielding a higher-dimensional Gödel universe. The considerations of n rotations and also of constant curvature spaces is a new line of generalization and is being considered for the first time.

Schemes for Teleportation of an Unknown Single-Qubit Quantum State by Using an Arbitrary High-Dimensional Entangled State

NASA Astrophysics Data System (ADS)

Zhan, You-Bang; Zhang, Qun-Yong; Wang, Yu-Wu; Ma, Peng-Cheng

2010-01-01

We propose a scheme to teleport an unknown single-qubit state by using a high-dimensional entangled state as the quantum channel. As a special case, a scheme for teleportation of an unknown single-qubit state via three-dimensional entangled state is investigated in detail. Also, this scheme can be directly generalized to an unknown f-dimensional state by using a d-dimensional entangled state (d > f) as the quantum channel.

Quantum error-correcting code for ternary logic

NASA Astrophysics Data System (ADS)

Majumdar, Ritajit; Basu, Saikat; Ghosh, Shibashis; Sur-Kolay, Susmita

2018-05-01

Ternary quantum systems are being studied because they provide more computational state space per unit of information, known as qutrit. A qutrit has three basis states, thus a qubit may be considered as a special case of a qutrit where the coefficient of one of the basis states is zero. Hence both (2 ×2 ) -dimensional and (3 ×3 ) -dimensional Pauli errors can occur on qutrits. In this paper, we (i) explore the possible (2 ×2 ) -dimensional as well as (3 ×3 ) -dimensional Pauli errors in qutrits and show that any pairwise bit swap error can be expressed as a linear combination of shift errors and phase errors, (ii) propose a special type of error called a quantum superposition error and show its equivalence to arbitrary rotation, (iii) formulate a nine-qutrit code which can correct a single error in a qutrit, and (iv) provide its stabilizer and circuit realization.

Disparities in Access to Healthcare Transition Services for Adolescents with Down Syndrome.

PubMed

Nugent, James; Gorman, Gregory; Erdie-Lalena, Christine R

2018-06-01

To compare healthcare transition planning in adolescents with Down syndrome with adolescents with other special healthcare needs. Data were drawn from the 2009-2010 National Survey of Children with Special Health Care Needs, a nationally representative sample with 17 114 adolescents aged 12-17 years. Parents were asked whether providers and the study child had discussed shifting to an adult provider, changing healthcare needs, maintaining health insurance coverage, and taking responsibility for self-care. The transition core outcome was a composite measure based on the results of these 4 questions. Multivariable logistic regression determined the association between Down syndrome and the transition core outcome as well as each of the 4 individual component measures. Although 40% of adolescents with other special healthcare needs met the transition core outcome, 11.0% of adolescents with Down syndrome met this outcome. Adolescents with Down syndrome were less likely to be encouraged to take responsibility for their health (32.2% vs 78.4%). After adjustment for demographic, socioeconomic, and health-related factors, adolescents with Down syndrome had 4 times the odds of not meeting the transition core outcome. For the component measures, Down syndrome adolescents had 4 times the odds of not being encouraged to take responsibility for self-care. Medical home access increased the odds of transition preparation. Adolescents with Down syndrome experience disparities in access to transition services. Provider goals for adolescents with Down syndrome should encourage as much independence as possible in their personal care and social lives. Copyright © 2018 Elsevier Inc. All rights reserved.

Index theory for the boundaries of complex analytic varieties

PubMed Central

Yau, Stephen S.-T.

1980-01-01

A result of boundary p-index is presented for a vector bundle on a complex analytic variety with boundary. A characterization of which odd-dimensional, real submanifolds of [unk]N are boundaries of complex subvarieties (respectively submanifolds) in [unk]N is given. PMID:16592783

Large Directed Flow of Open Charm Mesons Probes the Three-Dimensional Distribution of Matter in Heavy-Ion Collisions

NASA Astrophysics Data System (ADS)

Chatterjee, Sandeep; BoŻek, Piotr

2018-05-01

Thermalized matter created in noncentral relativistic heavy-ion collisions is expected to be tilted in the reaction plane with respect to the beam axis. The most notable consequence of this forward-backward symmetry breaking is the observation of rapidity-odd directed flow for charged particles. On the other hand, the production points for heavy quarks are forward-backward symmetric and shifted in the transverse plane with respect to the fireball. The drag on heavy quarks from the asymmetrically distributed thermalized matter generates substantial directed flow for heavy flavor mesons. We predict a very large rapidity-odd directed flow of D mesons in noncentral Au-Au collisions at √{sN N}=200 GeV , several times larger than for charged particles. A possible experimental observation of a large directed flow for heavy flavor mesons would represent an almost direct probe of the three-dimensional distribution of matter in heavy-ion collisions.

Image-based reconstruction of three-dimensional myocardial infarct geometry for patient-specific modeling of cardiac electrophysiology

PubMed Central

Ukwatta, Eranga; Arevalo, Hermenegild; Rajchl, Martin; White, James; Pashakhanloo, Farhad; Prakosa, Adityo; Herzka, Daniel A.; McVeigh, Elliot; Lardo, Albert C.; Trayanova, Natalia A.; Vadakkumpadan, Fijoy

2015-01-01

Purpose: Accurate three-dimensional (3D) reconstruction of myocardial infarct geometry is crucial to patient-specific modeling of the heart aimed at providing therapeutic guidance in ischemic cardiomyopathy. However, myocardial infarct imaging is clinically performed using two-dimensional (2D) late-gadolinium enhanced cardiac magnetic resonance (LGE-CMR) techniques, and a method to build accurate 3D infarct reconstructions from the 2D LGE-CMR images has been lacking. The purpose of this study was to address this need. Methods: The authors developed a novel methodology to reconstruct 3D infarct geometry from segmented low-resolution (Lo-res) clinical LGE-CMR images. Their methodology employed the so-called logarithm of odds (LogOdds) function to implicitly represent the shape of the infarct in segmented image slices as LogOdds maps. These 2D maps were then interpolated into a 3D image, and the result transformed via the inverse of LogOdds to a binary image representing the 3D infarct geometry. To assess the efficacy of this method, the authors utilized 39 high-resolution (Hi-res) LGE-CMR images, including 36 in vivo acquisitions of human subjects with prior myocardial infarction and 3 ex vivo scans of canine hearts following coronary ligation to induce infarction. The infarct was manually segmented by trained experts in each slice of the Hi-res images, and the segmented data were downsampled to typical clinical resolution. The proposed method was then used to reconstruct 3D infarct geometry from the downsampled images, and the resulting reconstructions were compared with the manually segmented data. The method was extensively evaluated using metrics based on geometry as well as results of electrophysiological simulations of cardiac sinus rhythm and ventricular tachycardia in individual hearts. Several alternative reconstruction techniques were also implemented and compared with the proposed method. Results: The accuracy of the LogOdds method in reconstructing 3D infarct geometry, as measured by the Dice similarity coefficient, was 82.10% ± 6.58%, a significantly higher value than those of the alternative reconstruction methods. Among outcomes of electrophysiological simulations with infarct reconstructions generated by various methods, the simulation results corresponding to the LogOdds method showed the smallest deviation from those corresponding to the manual reconstructions, as measured by metrics based on both activation maps and pseudo-ECGs. Conclusions: The authors have developed a novel method for reconstructing 3D infarct geometry from segmented slices of Lo-res clinical 2D LGE-CMR images. This method outperformed alternative approaches in reproducing expert manual 3D reconstructions and in electrophysiological simulations. PMID:26233186

Image-based reconstruction of three-dimensional myocardial infarct geometry for patient-specific modeling of cardiac electrophysiology

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

Ukwatta, Eranga, E-mail: eukwatt1@jhu.edu; Arevalo, Hermenegild; Pashakhanloo, Farhad

Purpose: Accurate three-dimensional (3D) reconstruction of myocardial infarct geometry is crucial to patient-specific modeling of the heart aimed at providing therapeutic guidance in ischemic cardiomyopathy. However, myocardial infarct imaging is clinically performed using two-dimensional (2D) late-gadolinium enhanced cardiac magnetic resonance (LGE-CMR) techniques, and a method to build accurate 3D infarct reconstructions from the 2D LGE-CMR images has been lacking. The purpose of this study was to address this need. Methods: The authors developed a novel methodology to reconstruct 3D infarct geometry from segmented low-resolution (Lo-res) clinical LGE-CMR images. Their methodology employed the so-called logarithm of odds (LogOdds) function to implicitlymore » represent the shape of the infarct in segmented image slices as LogOdds maps. These 2D maps were then interpolated into a 3D image, and the result transformed via the inverse of LogOdds to a binary image representing the 3D infarct geometry. To assess the efficacy of this method, the authors utilized 39 high-resolution (Hi-res) LGE-CMR images, including 36 in vivo acquisitions of human subjects with prior myocardial infarction and 3 ex vivo scans of canine hearts following coronary ligation to induce infarction. The infarct was manually segmented by trained experts in each slice of the Hi-res images, and the segmented data were downsampled to typical clinical resolution. The proposed method was then used to reconstruct 3D infarct geometry from the downsampled images, and the resulting reconstructions were compared with the manually segmented data. The method was extensively evaluated using metrics based on geometry as well as results of electrophysiological simulations of cardiac sinus rhythm and ventricular tachycardia in individual hearts. Several alternative reconstruction techniques were also implemented and compared with the proposed method. Results: The accuracy of the LogOdds method in reconstructing 3D infarct geometry, as measured by the Dice similarity coefficient, was 82.10% ± 6.58%, a significantly higher value than those of the alternative reconstruction methods. Among outcomes of electrophysiological simulations with infarct reconstructions generated by various methods, the simulation results corresponding to the LogOdds method showed the smallest deviation from those corresponding to the manual reconstructions, as measured by metrics based on both activation maps and pseudo-ECGs. Conclusions: The authors have developed a novel method for reconstructing 3D infarct geometry from segmented slices of Lo-res clinical 2D LGE-CMR images. This method outperformed alternative approaches in reproducing expert manual 3D reconstructions and in electrophysiological simulations.« less

Flipping-shuttle oscillations of bright one- and two-dimensional solitons in spin-orbit-coupled Bose-Einstein condensates with Rabi mixing

NASA Astrophysics Data System (ADS)

Sakaguchi, Hidetsugu; Malomed, Boris A.

2017-10-01

We analyze the possibility of macroscopic quantum effects in the form of coupled structural oscillations and shuttle motion of bright two-component spin-orbit-coupled striped (one-dimensional, 1D) and semivortex (two-dimensional, 2D) matter-wave solitons, under the action of linear mixing (Rabi coupling) between the components. In 1D, the intrinsic oscillations manifest themselves as flippings between spatially even and odd components of striped solitons, while in 2D the system features periodic transitions between zero-vorticity and vortical components of semivortex solitons. The consideration is performed by means of a combination of analytical and numerical methods.

Photonic band structures in one-dimensional photonic crystals containing Dirac materials

NASA Astrophysics Data System (ADS)

Wang, Lin; Wang, Li-Gang

2015-09-01

We have investigated the band structures of one-dimensional photonic crystals (1DPCs) composed of Dirac materials and ordinary dielectric media. It is found that there exist an omnidirectional passing band and a kind of special band, which result from the interaction of the evanescent and propagating waves. Due to the interface effect and strong dispersion, the electromagnetic fields inside the special bands are strongly enhanced. It is also shown that the properties of these bands are invariant upon the lattice constant but sensitive to the resonant conditions.

Spectroscopy of a one-dimensional V-shaped quantum well with a point impurity

NASA Astrophysics Data System (ADS)

Fassari, S.; Gadella, M.; Glasser, M. L.; Nieto, L. M.

2018-02-01

We consider the one-dimensional Hamiltonian with a V-shaped potential H0 = 1/2 [ -d2/dx2 + | x | ], decorated with a point impurity of either δ-type, or local δ‧-type or even nonlocal δ‧-type, thus yielding three exactly solvable models. We analyse the behaviour of the change in the energy levels when an interaction of the type - λ δ(x) or - λ δ(x -x0) is switched on. In the first case, even energy levels, pertaining to antisymmetric bound states, remain invariant with respect to λ even though odd energy levels, pertaining to symmetric bound states, decrease as λ increases. In the second, all energy levels decrease when the factor λ increases. A similar study has been performed for the so-called nonlocal δ‧ interaction, requiring a coupling constant renormalisation, which implies the replacement of the form factor λ by a renormalised form factor β. In terms of β, odd energy levels are unchanged. However, we show the existence of level crossings: after a fixed value of β the energy of each even level, with the natural exception of the first one, becomes lower than the constant energy of the previous odd level. Finally, we consider an interaction of the type - λδ(x) + μδ‧(x) , and analyse in detail the discrete spectrum of the resulting self-adjoint Hamiltonian.

The distribution of odd nitrogen in the lower stratosphere and possible perturbations caused by stratospheric air transport

NASA Technical Reports Server (NTRS)

Isaksen, I. S. A.; Hesstvedt, E.

1973-01-01

In the lower stratosphere a significant production of odd nitrogen results from the reaction N2O + O(D-1) yields 2NO. Since the transport is relatively slow, odd nitrogen builds up with a maximum mixing ratio of 2 x 10 to the minus 8th power at 30 Km. Profiles of odd nitrogen, for different latitudes, winter and summer, are computed from one-dimensional transport models. Variations with latitude are small. Horizontal transport is therefore not believed to alter our results significantly. In order to evaluate the effect of odd nitrogen upon the ozone layer, NO(x) profiles are calculated. OH is here a key component, since it converts NO2 to HNO3. In the region where ozone is determined by chemistry rather than by transport (above 25 km), NO2 is found to be relatively abundant. The effect of stratospheric transport on the NO(x) distribution is shown to depend critically upon the height of emission. The effect increases by a factor of 5 or more for a change of flight level from 18 km to 23 km. This strong dependence should be duely considered when future stratospheric transport is discussed.

Topological Superfluid and Majorana Zero Modes in Synthetic Dimension

PubMed Central

Yan, Zhongbo; Wan, Shaolong; Wang, Zhong

2015-01-01

Recently it has been shown that multicomponent spin-orbit-coupled fermions in one-dimensional optical lattices can be viewed as spinless fermions moving in two-dimensional synthetic lattices with synthetic magnetic flux. The quantum Hall edge states in these systems have been observed in recent experiments. In this paper we study the effect of an attractive Hubbard interaction. Since the Hubbard interaction is long-range in the synthetic dimension, it is able to efficiently induce Cooper pairing between the counterpropagating chiral edge states. The topological class of the resultant one-dimensional superfluid is determined by the parity (even/odd) of the Chern number in the two-dimensional synthetic lattice. We also show the presence of a chiral symmetry in our model, which implies Z classification and the robustness of multiple zero modes when this symmetry is unbroken. PMID:26515084

CP-odd Higgs boson production in eγ collisions

NASA Astrophysics Data System (ADS)

Sasaki, Ken; Uematsu, Tsuneo

2018-06-01

We investigate the CP-odd Higgs boson production via two-photon processes in eγ collisions. The CP-odd Higgs boson, which we denote as A0, is expected to appear in the Two-Higgs Doublet Models (2HDM) as a minimal extension of Higgs sector for which the Minimal Supersymmetric Standard Model (MSSM) is a special case. The scattering amplitude for eγ → eA0 is evaluated at the electroweak one-loop level. The dominant contribution comes from top-quark loops when A0 boson is rather light and tan ⁡ β is not large. There are no contributions from the W-boson and Z-boson loops nor the scalar top-quark (stop) loops. The differential cross section for the A0 production is analyzed.

Clinical Implications of a Dimensional Approach: The Normal:Abnormal Spectrum of Early Irritability.

PubMed

Wakschlag, Lauren S; Estabrook, Ryne; Petitclerc, Amelie; Henry, David; Burns, James L; Perlman, Susan B; Voss, Joel L; Pine, Daniel S; Leibenluft, Ellen; Briggs-Gowan, Margaret L

2015-08-01

The importance of dimensional approaches is widely recognized, but an empirical base for clinical application is lacking. This is particularly true for irritability, a dimensional phenotype that cuts across many areas of psychopathology and manifests early in life. We examine longitudinal, dimensional patterns of irritability and their clinical import in early childhood. Irritability was assessed longitudinally over an average of 16 months in a clinically enriched, diverse community sample of preschoolers (N = 497; mean = 4.2 years; SD = 0.8). Using the Temper Loss scale of the Multidimensional Assessment Profile of Disruptive Behavior (MAP-DB) as a developmentally sensitive indicator of early childhood irritability, we examined its convergent/divergent, clinical, and incremental predictive validity, and modeled its linear and nonlinear associations with clinical risk. The Temper Loss scale demonstrated convergent and divergent validity to child and maternal factors. In multivariate analyses, Temper Loss predicted mood (separation anxiety disorder [SAD], generalized anxiety disorder [GAD], and depression/dysthymia), disruptive (oppositional defiant disorder [ODD], attention-deficit/hyperactivity disorder [ADHD], and conduct disorder [CD]) symptoms. Preschoolers with even mildly elevated Temper Loss scale scores showed substantially increased risk of symptoms and disorders. For ODD, GAD, SAD, and depression, increases in Temper Loss scale scores at the higher end of the dimension had a greater impact on symptoms relative to increases at the lower end. Temper Loss scale scores also showed incremental validity over DSM-IV disorders in predicting subsequent impairment. Finally, accounting for the substantial heterogeneity in longitudinal patterns of Temper Loss significantly improved prediction of mood and disruptive symptoms. Dimensional, longitudinal characterization of irritability informs clinical prediction. A vital next step will be empirically generating parameters for the incorporation of dimensional information into clinical decision-making with reasonable certainty. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. All rights reserved.

Superconducting proximity in three-dimensional Dirac materials: Odd-frequency, pseudoscalar, pseudovector, and tensor-valued superconducting orders

NASA Astrophysics Data System (ADS)

Faraei, Zahra; Jafari, S. A.

2017-10-01

We find that a conventional s -wave superconductor in proximity to a three-dimensional Dirac material (3DDM), to all orders of perturbation in tunneling, induces a combination of s - and p -wave pairing only. We show that the Lorentz invariance of the superconducting pairing prevents the formation of Cooper pairs with higher orbital angular momenta in the 3DDM. This no-go theorem acquires stronger form when the probability of tunneling from the conventional superconductor to positive and negative energy states of 3DDM are equal. In this case, all the p -wave contribution except for the lowest order, identically vanish and hence we obtain an exact result for the induced p -wave superconductivity in 3DDM. Fierz decomposing the superconducting matrix we find that the temporal component of the vector superconducting order and the spatial components of the pseudovector order have odd-frequency pairing symmetry. We find that the latter is odd with respect to exchange of position and chirality of the electrons in the Cooper pair and is a spin-triplet, which is necessary for NMR detection of such an exotic pseudovector pairing. Moreover, we show that the tensorial order breaks into a polar vector and an axial vector and both of them have conventional pairing symmetry except for being a spin triplet. According to our study, for gapless 3DDM, the tensorial superconducting order will be the only order that is odd with respect to the chemical potential μ . Therefore we predict that a transverse p -n junction binds Majorana fermions. This effect can be used to control the neutral Majorana fermions with electric fields.

Fractional Quantization of the Hall Effect

DOE R&D Accomplishments Database

Laughlin, R. B.

1984-02-27

The Fractional Quantum Hall Effect is caused by the condensation of a two-dimensional electron gas in a strong magnetic field into a new type of macroscopic ground state, the elementary excitations of which are fermions of charge 1/m, where m is an odd integer. A mathematical description is presented.

Generation of three-dimensional delaunay meshes from weakly structured and inconsistent data

NASA Astrophysics Data System (ADS)

Garanzha, V. A.; Kudryavtseva, L. N.

2012-03-01

A method is proposed for the generation of three-dimensional tetrahedral meshes from incomplete, weakly structured, and inconsistent data describing a geometric model. The method is based on the construction of a piecewise smooth scalar function defining the body so that its boundary is the zero isosurface of the function. Such implicit description of three-dimensional domains can be defined analytically or can be constructed from a cloud of points, a set of cross sections, or a "soup" of individual vertices, edges, and faces. By applying Boolean operations over domains, simple primitives can be combined with reconstruction results to produce complex geometric models without resorting to specialized software. Sharp edges and conical vertices on the domain boundary are reproduced automatically without using special algorithms. Refs. 42. Figs. 25.

Special Bohr-Sommerfeld Lagrangian submanifolds

NASA Astrophysics Data System (ADS)

Tyurin, N. A.

2016-12-01

We introduce a new notion in symplectic geometry, that of speciality for Lagrangian submanifolds satisfying the Bohr- Sommerfeld condition. We show that it enables one to construct finite-dimensional moduli spaces of special Bohr- Sommerfeld Lagrangian submanifolds with respect to any ample line bundle on an algebraic variety with a Hodge metric regarded as the symplectic form. This construction can be used to study mirror symmetry.

Predicting Depression and Anxiety from Oppositional Defiant Disorder Symptoms in Elementary School-Age Girls and Boys with Conduct Problems.

PubMed

Déry, Michèle; Lapalme, Mélanie; Jagiellowicz, Jadzia; Poirier, Martine; Temcheff, Caroline; Toupin, Jean

2017-02-01

This study investigated the relationship between the three DSM-5 categories of oppositional defiant disorder (ODD) symptoms (irritable mood, defiant behavior, vindictive behavior) and anxiety/depression in girls and boys with conduct problems (CP) while controlling for comorbid child psychopathology at baseline. Data were drawn from an ongoing longitudinal study of 6- to 9-year-old French-Canadian children (N = 276; 40.8 % girls) receiving special educational services for CP at school and followed for 2 years. Using linear regression analysis, the results showed that irritable mood symptoms predicted a higher level of depression and anxiety in girls and boys 2 years later, whereas the behavioral symptoms of ODD (e.g., defiant, vindictive symptoms) were linked to lower depression scores. The contribution of ODD symptoms to these predictions, while statistically significant, remained modest. The usefulness of ODD irritable symptoms as a marker for identifying girls and boys with CP who are more vulnerable to developing internalizing problems is discussed.

Finite-dimensional Liouville integrable Hamiltonian systems generated from Lax pairs of a bi-Hamiltonian soliton hierarchy by symmetry constraints

NASA Astrophysics Data System (ADS)

Manukure, Solomon

2018-04-01

We construct finite-dimensional Hamiltonian systems by means of symmetry constraints from the Lax pairs and adjoint Lax pairs of a bi-Hamiltonian hierarchy of soliton equations associated with the 3-dimensional special linear Lie algebra, and discuss the Liouville integrability of these systems based on the existence of sufficiently many integrals of motion.

On the n-symplectic structure of faithful irreducible representations

NASA Astrophysics Data System (ADS)

Norris, L. K.

2017-04-01

Each faithful irreducible representation of an N-dimensional vector space V1 on an n-dimensional vector space V2 is shown to define a unique irreducible n-symplectic structure on the product manifold V1×V2 . The basic details of the associated Poisson algebra are developed for the special case N = n2, and 2n-dimensional symplectic submanifolds are shown to exist.

Three-dimensional laser window formation

NASA Technical Reports Server (NTRS)

Verhoff, Vincent G.

1992-01-01

The NASA Lewis Research Center has developed and implemented a unique process for forming flawless three-dimensional laser windows. These windows represent a major part of specialized, nonintrusive laser data acquisition systems used in a variety of compressor and turbine research test facilities. This report discusses in detail the aspects of three-dimensional laser window formation. It focuses on the unique methodology and the peculiarities associated with the formation of these windows. Included in this discussion are the design criteria, bonding mediums, and evaluation testing for three-dimensional laser windows.

Computer modelling of grain microstructure in three dimensions

NASA Astrophysics Data System (ADS)

Narayan, K. Lakshmi

We present a program that generates the two-dimensional micrographs of a three dimensional grain microstructure. The code utilizes a novel scanning, pixel mapping technique to secure statistical distributions of surface areas, grain sizes, aspect ratios, perimeters, number of nearest neighbors and volumes of the randomly nucleated particles. The program can be used for comparing the existing theories of grain growth, and interpretation of two-dimensional microstructure of three-dimensional samples. Special features have been included to minimize the computation time and resource requirements.

Analysis of factors associated with seatbelt wearing among rear passengers in Malaysia.

PubMed

Mohamed, Norlen; Mohd Yusoff, Muhammad Fadhli; Isah, Noradrenalina; Othman, Ihamah; Syed Rahim, Sharifah-Allyana; Paiman, Noorfaradilla

2011-03-01

A cross-sectional survey using a self-administered questionnaire was conducted among 793 rear passengers in Malaysia. Logistic regression was performed to analyse the association of rear seatbelt wearing with 12 independent variables. Seven factors were significantly associated with rear seatbelt wearing. Experience of being stopped by an enforcement officer for not wearing rear seatbelt yielded the highest odds ratio 2.3 (p = 0.002) followed by self-consciousness (odds ratio 1.7; p = 0.004), attitude (odds ratio 1.5, p = 0.001), and knowledge (odds ratio 1.4, p = 0.004). Age of participants and their perception of being caught by an enforcement officer were also significantly associated with rear seatbelt wearing, odds ratios were 1.03 (p = 0.004) and 1.1 (p = 0.004), respectively. In contrast, level of education was negatively associated with rear seatbelt wearing (odds ratio 0.59, p = 0.003). It was concluded that enforcement activities, knowledge and attitude on seatbelt wearing play a very important role in improving the rate of rear seatbelt wearing. Thus, efforts to increase these factors should be the special focus in designing education and social marketing activities to advocate rear seatbelt wearing.

A Lie based 4-dimensional higher Chern-Simons theory

NASA Astrophysics Data System (ADS)

Zucchini, Roberto

2016-05-01

We present and study a model of 4-dimensional higher Chern-Simons theory, special Chern-Simons (SCS) theory, instances of which have appeared in the string literature, whose symmetry is encoded in a skeletal semistrict Lie 2-algebra constructed from a compact Lie group with non discrete center. The field content of SCS theory consists of a Lie valued 2-connection coupled to a background closed 3-form. SCS theory enjoys a large gauge and gauge for gauge symmetry organized in an infinite dimensional strict Lie 2-group. The partition function of SCS theory is simply related to that of a topological gauge theory localizing on flat connections with degree 3 second characteristic class determined by the background 3-form. Finally, SCS theory is related to a 3-dimensional special gauge theory whose 2-connection space has a natural symplectic structure with respect to which the 1-gauge transformation action is Hamiltonian, the 2-curvature map acting as moment map.

Dimension-5 C P -odd operators: QCD mixing and renormalization

DOE PAGES

Bhattacharya, Tanmoy; Cirigliano, Vincenzo; Gupta, Rajan; ...

2015-12-23

Here, we study the off-shell mixing and renormalization of flavor-diagonal dimension-five T- and P-odd operators involving quarks, gluons, and photons, including quark electric dipole and chromoelectric dipole operators. Furthermore, we present the renormalization matrix to one loop in themore » $$\\bar{MS}$$ scheme. We also provide a definition of the quark chromoelectric dipole operator in a regularization-independent momentum-subtraction scheme suitable for nonperturbative lattice calculations and present the matching coefficients with the $$\\bar{MS}$$ scheme to one loop in perturbation theory, using both the naïve dimensional regularization and ’t Hooft–Veltman prescriptions for γ 5.« less

Understanding logistic regression analysis.

PubMed

Sperandei, Sandro

2014-01-01

Logistic regression is used to obtain odds ratio in the presence of more than one explanatory variable. The procedure is quite similar to multiple linear regression, with the exception that the response variable is binomial. The result is the impact of each variable on the odds ratio of the observed event of interest. The main advantage is to avoid confounding effects by analyzing the association of all variables together. In this article, we explain the logistic regression procedure using examples to make it as simple as possible. After definition of the technique, the basic interpretation of the results is highlighted and then some special issues are discussed.

Quasi-one-dimensional Hall physics in the Harper–Hofstadter–Mott model

NASA Astrophysics Data System (ADS)

Kozarski, Filip; Hügel, Dario; Pollet, Lode

2018-04-01

We study the ground-state phase diagram of the strongly interacting Harper–Hofstadter–Mott model at quarter flux on a quasi-one-dimensional lattice consisting of a single magnetic flux quantum in y-direction. In addition to superfluid phases with various density patterns, the ground-state phase diagram features quasi-one-dimensional analogs of fractional quantum Hall phases at fillings ν = 1/2 and 3/2, where the latter is only found thanks to the hopping anisotropy and the quasi-one-dimensional geometry. At integer fillings—where in the full two-dimensional system the ground-state is expected to be gapless—we observe gapped non-degenerate ground-states: at ν = 1 it shows an odd ‘fermionic’ Hall conductance, while the Hall response at ν = 2 consists of the transverse transport of a single particle–hole pair, resulting in a net zero Hall conductance. The results are obtained by exact diagonalization and in the reciprocal mean-field approximation.

Quantum solution for the one-dimensional Coulomb problem

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

Nunez-Yepez, H. N.; Salas-Brito, A. L.; Solis, Didier A.

2011-06-15

The one-dimensional hydrogen atom has been a much studied system with a wide range of applications. Since the pioneering work of Loudon [R. Loudon, Am. J. Phys. 27, 649 (1959).], a number of different features related to the nature of the eigenfunctions have been found. However, many of the claims made throughout the years in this regard are not correct--such as the existence of only odd eigenstates or of an infinite binding-energy ground state. We explicitly show that the one-dimensional hydrogen atom does not admit a ground state of infinite binding energy and that the one-dimensional Coulomb potential is notmore » its own supersymmetric partner. Furthermore, we argue that at the root of many such false claims lies the omission of a superselection rule that effectively separates the right side from the left side of the singularity of the Coulomb potential.« less

Optimal feedback control infinite dimensional parabolic evolution systems: Approximation techniques

NASA Technical Reports Server (NTRS)

Banks, H. T.; Wang, C.

1989-01-01

A general approximation framework is discussed for computation of optimal feedback controls in linear quadratic regular problems for nonautonomous parabolic distributed parameter systems. This is done in the context of a theoretical framework using general evolution systems in infinite dimensional Hilbert spaces. Conditions are discussed for preservation under approximation of stabilizability and detectability hypotheses on the infinite dimensional system. The special case of periodic systems is also treated.

Separation of variables in the special diagonal Hamilton-Jacobi equation: Application to the dynamical problem of a particle constrained on a moving surface

NASA Technical Reports Server (NTRS)

Blanchard, D. L.; Chan, F. K.

1973-01-01

For a time-dependent, n-dimensional, special diagonal Hamilton-Jacobi equation a necessary and sufficient condition for the separation of variables to yield a complete integral of the form was established by specifying the admissible forms in terms of arbitrary functions. A complete integral was then expressed in terms of these arbitrary functions and also the n irreducible constants. As an application of the results obtained for the two-dimensional Hamilton-Jacobi equation, analysis was made for a comparatively wide class of dynamical problems involving a particle moving in Euclidean three-dimensional space under the action of external forces but constrained on a moving surface. All the possible cases in which this equation had a complete integral of the form were obtained and these are tubulated for reference.

Determinants and conformal anomalies of GJMS operators on spheres

NASA Astrophysics Data System (ADS)

Dowker, J. S.

2011-03-01

The conformal anomalies and functional determinants of the Branson-GJMS operators, P2k, on the d-dimensional sphere are evaluated in explicit terms for any d and k such that k <= d/2 (if d is even). The determinants are given in terms of multiple gamma functions and a rational multiplicative anomaly, which vanishes for odd d. Taking the mode system on the sphere as the union of Neumann and Dirichlet ones on the hemisphere is a basic part of the method and leads to a heuristic explanation of the non-existence of 'super-critical' operators, 2k > d for even d. Significant use is made of the Barnes zeta function. The results are given in terms of ratios of determinants of operators on a (d + 1)-dimensional bulk dual sphere. For odd dimensions, the log determinant is written in terms of multiple sine functions and agreement is found with holographic computations, yielding an integral over a Plancherel measure. The N-D determinant ratio is also found explicitly for even dimensions. Ehrhart polynomials are encountered.

Rurality and nursing home quality: evidence from the 2004 National Nursing Home Survey.

PubMed

Kang, Yu; Meng, Hongdao; Miller, Nancy A

2011-12-01

To evaluate the impact of rural geographic location on nursing home quality of care in the United States. The study used cross-sectional observational design. We obtained resident- and facility-level data from 12,507 residents in 1,174 nursing homes from the 2004 National Nursing Home Survey. We used multilevel regression models to predict risk-adjusted rates of hospitalization, influenza and pneumococcal vaccination, and moderate to severe pain while controlling for resident and facility characteristics. Adjusting for covariates, residents in rural facilities were more likely to experience hospitalization (odds ratio [OR] = 1.50, 95% confidence interval [CI] = 1.16-1.94) and moderate to severe pain (OR = 1.68, 95% CI = 1.35-2.09). Significant facility-level predictors of higher quality included higher percentage of Medicaid beneficiaries, accreditation status, and special care programs. Medicare payment findings were mixed. Significant resident-level predictors included dementia diagnosis and being a "long-stay" resident. Rural residents were more likely to reside in facilities without accreditations or special care programs, factors that increased their odds of receiving poorer quality of care. Policy efforts to enhance Medicare payment approaches as well as increase rural facilities' accreditation status and provision of special care programs will likely reduce quality of care disparities in facilities.

Genetic influences on musical specialization: a twin study on choice of instrument and music genre.

PubMed

Mosing, Miriam A; Ullén, Fredrik

2018-05-09

Though several studies show that genetic factors influence individual differences in musical engagement, aptitude, and achievement, no study to date has investigated whether specialization among musically active individuals in terms of choice of instrument and genre is heritable. Using a large twin cohort, we explored whether individual differences in instrument choice, instrument category, and the type of music individuals engage in can entirely be explained by the environment or are partly due to genetic influences. About 10,000 Swedish twins answered an extensive questionnaire about music-related traits, including information on the instrument and genre they played. Of those, 1259 same-sex twin pairs reported to either play an instrument or sing. We calculated the odds ratios (ORs) for concordance in music choices (if both twins played) comparing identical and nonidentical twin pairs, with significant ORs indicating that identical twins are more likely to engage in the same type of music-related behavior than are nonidentical twins. The results showed that for almost all music-related variables, the odds were significantly higher for identical twins to play the same musical instrument or music genre, suggesting significant genetic influences on such music specialization. Possible interpretations and implications of the findings are discussed. © 2018 New York Academy of Sciences.

Organization Structure and Administrative Control: A Question of Dimensionality.

ERIC Educational Resources Information Center

Montanari, John R.; Freedman, Sara M.

1981-01-01

Used a sample of national firms (N=836) to investigate the relationship between specialization, formalization, and centralization in the functional work unit. Data indicated that the three variables compose a single dimension of organizational structure. Another finding was that, within this dimension, specialization, formalization, and…

Colorectal Specialization Increases Lymph Node Yield: Evidence from a National Database.

PubMed

Jeganathan, Arjun N; Shanmugan, Skandan; Bleier, Joshua I S; Hall, Glenn M; Paulson, Emily C

2016-07-01

Current guidelines recommend the evaluation of at least 12 lymph nodes (LNs) in the pathologic specimen following surgery for colorectal cancer (CRC). We sought to examine the role of colorectal specialization on nodal identification. We conducted a retrospective cohort study using SEER-Medicare data to examine the association between colorectal specialization and LN identification following surgery for colon and rectal adenocarcinoma between 2001 and 2009. Our dataset included patients >65 years who underwent surgical resection for CRC. We excluded patients with rectal cancer who had received neoadjuvant therapy. The primary outcome measure was the number of LNs identified in the pathologic specimen following surgery for CRC. Multivariate analysis was used to identify the association between surgical specialization and LN identification in the pathologic specimen. In multivariate analysis, odds of an adequate lymphadenectomy following surgery with a colorectal specialist were 1.32 and 1.41 times greater for colon and rectal cancer, respectively, than following surgery by a general surgeon (p < 0.001). These odds increased to 1.36 and 1.58, respectively, when analysis was limited to board-certified colorectal surgeons. Hospital factors associated with ≥12 LNs identified included high-volume CRC surgery (colon OR 1.84, p < 0.001; rectal OR 1.78, p < 0.001) and NCI-designated Cancer Centers (colon OR 1.75, p < 0.001; rectal OR 1.64; p = 0.007). Colorectal specialization and, in particular, board-certification in colorectal surgery, is significantly associated with increased LN identification following surgery for colon and rectal adenocarcinoma since the adoption of the 12-LN guideline in 2001.

Mobility Status as a Predictor of Obesity, Physical Activity, and Screen Time Use among Children Aged 5-11 Years in the United States.

PubMed

Wilson, Patrick B; Haegele, Justin A; Zhu, Xihe

2016-09-01

To examine physical activity participation, screen time habits, and the prevalence of overweight/obesity among children in the general population with mobility limitations and those enrolled in special education services. An observational, cross-sectional analysis of the 2011-2014 National Health and Nutrition Examination Survey, a representative sample of the US population. Mobility limitations, special education services utilization, proxy-reported physical activity and screen time, and overweight/obesity status were assessed in children aged 5-11 years. Boys with mobility limitations were less likely to meet physical activity guidelines (≥60 minutes daily) compared with those with no limitations (58.1% vs 74.4%, adjusted F = 4.61, P = .04). In a logistic regression model, boys with mobility limitations had significantly lower odds (0.42, 95% CI 0.20-0.86) of meeting physical activity guidelines. The prevalence of children meeting screen time recommendations (≤2 hours daily) among those receiving special education services (42.4%) was lower than children not receiving services (53.2%; adjusted F = 8.87, P < .01). In a logistic regression model, children receiving special education services showed a trend toward significantly lower odds (0.74, 95% CI 0.54-1.03, P = .07) of meeting screen time recommendations. No statistically significant differences for overweight/obesity were found. Clear differences were present in physical activity between boys with and without mobility limitations. Furthermore, children receiving special education services demonstrated a lower likelihood of meeting screen time recommendations. Children with disabilities may benefit from targeted interventions aimed at increasing physical activity while decreasing screen time. Copyright © 2016 Elsevier Inc. All rights reserved.

Association of Competition Volume, Club Sports, and Sport Specialization With Sex and Lower Extremity Injury History in High School Athletes

PubMed Central

Post, Eric G.; Bell, David R.; Trigsted, Stephanie M.; Pfaller, Adam Y.; Hetzel, Scott J.; Brooks, M. Alison; McGuine, Timothy A.

2017-01-01

Background: High school athletes are increasingly encouraged to participate in 1 sport year-round to increase their sport skills. However, no study has examined the association of competition volume, club sport participation, and sport specialization with sex and lower extremity injury (LEI) in a large sample of high school athletes. Hypothesis: Increased competition volume, participating on a club team outside of school sports, and high levels of specialization will all be associated with a history of LEI. Girls will be more likely to engage in higher competition volume, participate on a club team, and be classified as highly specialized. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: High school athletes completed a questionnaire prior to the start of their competitive season regarding their sport participation and previous injury history. Multivariable logistic regression analyses were used to investigate associations of competition volume, club sport participation, and sport specialization with history of LEI, adjusting for sex. Results: A cohort of 1544 high school athletes (780 girls; grades 9-12) from 29 high schools completed the questionnaire. Girls were more likely to participate at high competition volume (23.2% vs 11.0%, χ2 = 84.7, P < 0.001), participate on a club team (61.2% vs 37.2%, χ2 = 88.3, P < 0.001), and be highly specialized (16.4% vs 10.4%, χ2 = 19.7, P < 0.001). Athletes with high competition volume, who participated in a club sport, or who were highly specialized had greater odds of reporting a previous LEI than those with low competition volume (odds ratio [OR], 2.08; 95% CI, 1.55-2.80; P < 0.001), no club sport participation (OR, 1.50; 95% CI, 1.20-1.88; P < 0.001), or low specialization (OR, 2.58; 95% CI, 1.88-3.54; P < 0.001), even after adjusting for sex. Conclusion: Participating in high sport volume, on a club team, or being highly specialized was associated with history of LEI. Girls were more likely to participate at high volumes, be active on club teams, or be highly specialized, potentially placing them at increased risk of injury. Clinical Relevance: Youth athletes, parents, and clinicians should be aware of the potential risks of intense, year-round participation in organized sports. PMID:28628419

Association of Competition Volume, Club Sports, and Sport Specialization With Sex and Lower Extremity Injury History in High School Athletes.

PubMed

Post, Eric G; Bell, David R; Trigsted, Stephanie M; Pfaller, Adam Y; Hetzel, Scott J; Brooks, M Alison; McGuine, Timothy A

High school athletes are increasingly encouraged to participate in 1 sport year-round to increase their sport skills. However, no study has examined the association of competition volume, club sport participation, and sport specialization with sex and lower extremity injury (LEI) in a large sample of high school athletes. Increased competition volume, participating on a club team outside of school sports, and high levels of specialization will all be associated with a history of LEI. Girls will be more likely to engage in higher competition volume, participate on a club team, and be classified as highly specialized. Cross-sectional study. Level 3. High school athletes completed a questionnaire prior to the start of their competitive season regarding their sport participation and previous injury history. Multivariable logistic regression analyses were used to investigate associations of competition volume, club sport participation, and sport specialization with history of LEI, adjusting for sex. A cohort of 1544 high school athletes (780 girls; grades 9-12) from 29 high schools completed the questionnaire. Girls were more likely to participate at high competition volume (23.2% vs 11.0%, χ 2 = 84.7, P < 0.001), participate on a club team (61.2% vs 37.2%, χ 2 = 88.3, P < 0.001), and be highly specialized (16.4% vs 10.4%, χ 2 = 19.7, P < 0.001). Athletes with high competition volume, who participated in a club sport, or who were highly specialized had greater odds of reporting a previous LEI than those with low competition volume (odds ratio [OR], 2.08; 95% CI, 1.55-2.80; P < 0.001), no club sport participation (OR, 1.50; 95% CI, 1.20-1.88; P < 0.001), or low specialization (OR, 2.58; 95% CI, 1.88-3.54; P < 0.001), even after adjusting for sex. Participating in high sport volume, on a club team, or being highly specialized was associated with history of LEI. Girls were more likely to participate at high volumes, be active on club teams, or be highly specialized, potentially placing them at increased risk of injury. Youth athletes, parents, and clinicians should be aware of the potential risks of intense, year-round participation in organized sports.

SPECIAL ISSUE DEVOTED TO THE 80TH BIRTHDAY OF S.A. AKHMANOV: Excitation of coherent polaritons in a two-dimensional atomic lattice

NASA Astrophysics Data System (ADS)

Barinov, I. O.; Alodzhants, A. P.; Arakelyan, Sergei M.

2009-07-01

We describe a new type of spatially periodic structure (lattice models): a polaritonic crystal formed by a two-dimensional lattice of trapped two-level atoms interacting with the electromagnetic field in a cavity (or in a one-dimensional array of tunnelling-coupled microcavities), which allows polaritons to be fully localised. Using a one-dimensional polaritonic crystal as an example, we analyse conditions for quantum degeneracy of a lower-polariton gas and those for quantum optical information recording and storage.

Two-dimensional heteroclinic attractor in the generalized Lotka-Volterra system

NASA Astrophysics Data System (ADS)

Afraimovich, Valentin S.; Moses, Gregory; Young, Todd

2016-05-01

We study a simple dynamical model exhibiting sequential dynamics. We show that in this model there exist sets of parameter values for which a cyclic chain of saddle equilibria, O k , k=1,\\ldots,p , have two-dimensional unstable manifolds that contain orbits connecting each O k to the next two equilibrium points O k+1 and O k+2 in the chain ({{O}p+1}={{O}1} ). We show that the union of these equilibria and their unstable manifolds form a two-dimensional surface with a boundary that is homeomorphic to a cylinder if p is even and a Möbius strip if p is odd. If, further, each equilibrium in the chain satisfies a condition called ‘dissipativity’, then this surface is asymptotically stable.

Simulations of dusty plasmas using a special-purpose computer system designed for gravitational N-body problems

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

Yamamoto, K.; Mizuno, Y.; Hibino, S.

2006-01-15

Simulations of dusty plasmas were performed using GRAPE-6, a special-purpose computer designed for gravitational N-body problems. The collective behavior of dust particles, which are injected into the plasma, was studied by means of three-dimensional computer simulations. As an example of a dusty plasma simulation, experiments on Coulomb crystals in plasmas are simulated. Formation of a quasi-two-dimensional Coulomb crystal has been observed under typical laboratory conditions. Another example was to simulate movement of dust particles in plasmas under microgravity conditions. Fully three-dimensional spherical structures of dust clouds have been observed. For the simulation of a dusty plasma in microgravity with 3x10{supmore » 4} particles, GRAPE-6 can perform the whole operation 1000 times faster than by using a Pentium 4 1.6 GHz processor.« less

Strong efficiency improvement in dye-sensitized solar cells by novel multi-dimensional TiO2 photoelectrode

NASA Astrophysics Data System (ADS)

Zhao, Fengyang; Ma, Rong; Jiang, Yongjian

2018-03-01

Titanium dioxide (TiO2) based dye-sensitized solar cells (DSSCs) often exhibit superior power conversion performance. Here we report a DSSC with novel hierarchical TiO2 composite structure (TCS) composed of anatase TiO2 micro-spheres and rutile TiO2 nanobelt framework by hydrothermal approach for high-performance. As photoanode, the TCS based DSSC shows a strong efficiency enhancement by 58% compared with Degussa TiO2 (P25)-DSSC (4.33%). The excellent performance is mainly attribute to its special multi-dimensional structures of TiO2: much active sites of 0D nanoparticle with exposed excellent {001} facet, special electronic transmission channel of 1D nanobelt, good dye adsorption capacity of 2D nanosheet and high light scattering ability of 3D micro-spheres. The novel multi-dimensional TCS materials will open up a new avenue to the electronic devices fields.

A cluster analysis method for identification of subpopulations of cells in flow cytometric list-mode arrays

NASA Technical Reports Server (NTRS)

Li, Z. K.

1985-01-01

A specialized program was developed for flow cytometric list-mode data using an heirarchical tree method for identifying and enumerating individual subpopulations, the method of principal components for a two-dimensional display of 6-parameter data array, and a standard sorting algorithm for characterizing subpopulations. The program was tested against a published data set subjected to cluster analysis and experimental data sets from controlled flow cytometry experiments using a Coulter Electronics EPICS V Cell Sorter. A version of the program in compiled BASIC is usable on a 16-bit microcomputer with the MS-DOS operating system. It is specialized for 6 parameters and up to 20,000 cells. Its two-dimensional display of Euclidean distances reveals clusters clearly, as does its 1-dimensional display. The identified subpopulations can, in suitable experiments, be related to functional subpopulations of cells.

The relativistic invariance of 4D-shapes

NASA Astrophysics Data System (ADS)

Calosi, Claudio

2015-05-01

A recent debate in the metaphysics of physics focuses on the invariance and intrinsicality of four-dimensional shapes in the Special Theory of Relativity. Davidson (2014) argues that four-dimensional shapes cannot be intrinsic properties of persisting objects because they have to be relativized to reference frames. Balashov (2014a) criticizes such an argument in that it mistakes four-dimensional shapes with their three-dimensional projections on the axes of those frames. This paper adds to that debate. Rather than criticizing an argument against the relativistic invariance of four-dimensional shapes, as Balashov did, it offers a direct argument in favor of such an invariance.

Global Discrete Artificial Boundary Conditions for Time-Dependent Wave Propagation

NASA Astrophysics Data System (ADS)

Ryaben'kii, V. S.; Tsynkov, S. V.; Turchaninov, V. I.

2001-12-01

We construct global artificial boundary conditions (ABCs) for the numerical simulation of wave processes on unbounded domains using a special nondeteriorating algorithm that has been developed previously for the long-term computation of wave-radiation solutions. The ABCs are obtained directly for the discrete formulation of the problem; in so doing, neither a rational approximation of “nonreflecting kernels” nor discretization of the continuous boundary conditions is required. The extent of temporal nonlocality of the new ABCs appears fixed and limited; in addition, the ABCs can handle artificial boundaries of irregular shape on regular grids with no fitting/adaptation needed and no accuracy loss induced. The nondeteriorating algorithm, which is the core of the new ABCs, is inherently three-dimensional, it guarantees temporally uniform grid convergence of the solution driven by a continuously operating source on arbitrarily long time intervals and provides unimprovable linear computational complexity with respect to the grid dimension. The algorithm is based on the presence of lacunae, i.e., aft fronts of the waves, in wave-type solutions in odd-dimensional spaces. It can, in fact, be built as a modification on top of any consistent and stable finite-difference scheme, making its grid convergence uniform in time and at the same time keeping the rate of convergence the same as that of the unmodified scheme. In this paper, we delineate the construction of the global lacunae-based ABCs in the framework of a discretized wave equation. The ABCs are obtained for the most general formulation of the problem that involves radiation of waves by moving sources (e.g., radiation of acoustic waves by a maneuvering aircraft). We also present systematic numerical results that corroborate the theoretical design properties of the ABC algorithm.

Temperament clusters associate with anxiety disorder comorbidity in depression.

PubMed

Paavonen, Vesa; Luoto, Kaisa; Lassila, Antero; Leinonen, Esa; Kampman, Olli

2018-08-15

Individual temperament is associated with psychiatric morbidity and could explain differences in psychiatric comorbidities. We investigated the association of temperament profile clusters with anxiety disorder comorbidity in patients with depression. We assessed the temperament of 204 specialized care-treated depressed patients with the Temperament and Character Inventory (TCI-R) and their diagnoses with the Mini International Neuropsychiatric Interview. Two-step cluster analysis was used for defining patients' temperament profiles and logistic regression analysis was used for predicting different anxiety disorders for various temperament profiles. Four temperament clusters were found: 1) Novelty seekers with highest Novelty Seeking scores (n = 56),2) Persistent with highest Persistence scores (n = 36), 3) Reserved with lowest Novelty Seeking scores (n = 66) and 4) Wearied with highest Harm avoidance, lowest Reward Dependence and lowest Persistence scores (n = 58). After adjusting for clinical variables, panic disorder and/or agoraphobia were predicted by Novelty seekers' temperament profile with odds ratio [OR] = 3.5 (95% confidence interval [CI] = 1.8 - 6.9, p < 0.001), social anxiety disorder was predicted by Wearied temperament profile with OR = 3.4 (95% CI = 1.6 - 7.5, p = 0.002), and generalized anxiety disorder was predicted by Reserved temperament profile with OR = 2.6 (95% CI = 1.2 - 5.3, p = 0.01). The patients' temperament profiles were assessed while displaying depressive symptoms, which may have affected results. Temperament clusters with unique dimensional profiles were specifically associated with different anxiety disorders in this study. These results suggest that TCI-R could offer a valuable dimensional method for predicting the risk of anxiety disorders in diverse depressed patients. Copyright © 2018 Elsevier B.V. All rights reserved.

A Corresponding Lie Algebra of a Reductive homogeneous Group and Its Applications

NASA Astrophysics Data System (ADS)

Zhang, Yu-Feng; Wu, Li-Xin; Rui, Wen-Juan

2015-05-01

With the help of a Lie algebra of a reductive homogeneous space G/K, where G is a Lie group and K is a resulting isotropy group, we introduce a Lax pair for which an expanding (2+1)-dimensional integrable hierarchy is obtained by applying the binormial-residue representation (BRR) method, whose Hamiltonian structure is derived from the trace identity for deducing (2+1)-dimensional integrable hierarchies, which was proposed by Tu, et al. We further consider some reductions of the expanding integrable hierarchy obtained in the paper. The first reduction is just right the (2+1)-dimensional AKNS hierarchy, the second-type reduction reveals an integrable coupling of the (2+1)-dimensional AKNS equation (also called the Davey-Stewartson hierarchy), a kind of (2+1)-dimensional Schrödinger equation, which was once reobtained by Tu, Feng and Zhang. It is interesting that a new (2+1)-dimensional integrable nonlinear coupled equation is generated from the reduction of the part of the (2+1)-dimensional integrable coupling, which is further reduced to the standard (2+1)-dimensional diffusion equation along with a parameter. In addition, the well-known (1+1)-dimensional AKNS hierarchy, the (1+1)-dimensional nonlinear Schrödinger equation are all special cases of the (2+1)-dimensional expanding integrable hierarchy. Finally, we discuss a few discrete difference equations of the diffusion equation whose stabilities are analyzed by making use of the von Neumann condition and the Fourier method. Some numerical solutions of a special stationary initial value problem of the (2+1)-dimensional diffusion equation are obtained and the resulting convergence and estimation formula are investigated. Supported by the Innovation Team of Jiangsu Province hosted by China University of Mining and Technology (2014), the National Natural Science Foundation of China under Grant No. 11371361, the Fundamental Research Funds for the Central Universities (2013XK03), and the Natural Science Foundation of Shandong Province under Grant No. ZR2013AL016

Effects of Callous-Unemotional Traits on the Association Between Parenting and Child Conduct Problems.

PubMed

Crum, Kathleen I; Waschbusch, Daniel A; Bagner, Daniel M; Coxe, Stefany

2015-12-01

The current study investigated whether and how callous-unemotional traits (CU) moderated the association between specific parenting practices and child conduct problems (CP) with a special consideration of informant patterns. Associations between CU, ODD and CD symptom severity, and the parenting practices of deficient monitoring, positive involvement, and negative/ineffective discipline were examined across parent and teacher reports on 851 elementary-school students. Relative to children with low CU, in children with high CU: (1) positive parenting was associated with lower CD, but increased ODD; (2) negative/ineffective discipline was associated with increased ODD; (3) deficient monitoring was associated with increased CD. Results were not robust across informants. These findings suggest that in the context of CU, the associations between parenting and CP differ based on parenting characteristics, CP dimensions, and informant, and that families may benefit from treatment targeting specific parenting practices based on CP symptom profiles.

Anomalous heat conduction in a one-dimensional ideal gas.

PubMed

Casati, Giulio; Prosen, Tomaz

2003-01-01

We provide firm convincing evidence that the energy transport in a one-dimensional gas of elastically colliding free particles of unequal masses is anomalous, i.e., the Fourier law does not hold. Our conclusions are confirmed by a theoretical and numerical analysis based on a Green-Kubo-type approach specialized to momentum-conserving lattices.

A New Three-Dimensional Educational Model Kit for Building DNA and RNA Molecules: Development and Evaluation

ERIC Educational Resources Information Center

Beltramini, Leila Maria; Araujo, Ana Paula Ulian; de Oliveira, Tales Henrique Goncalves; dos Santos Abel, Luciano Douglas; da Silva, Aparecido Rodrigues; dos Santos, Neusa Fernandes

2006-01-01

International specialized literature focused on research in biology education is sadly scarce, especially regarding biochemical and molecular aspects. In this light, researchers from this Centre for Structural Molecular Biotechnology developed and evaluated a three-dimensional educational model named "Building Life Molecules DNA and RNA." The…

New Double-Periodic Soliton Solutions for the (2+1)-Dimensional Breaking Soliton Equation

NASA Astrophysics Data System (ADS)

Liu, Jian-Guo; Tian, Yu

2018-05-01

Under investigation is the (2+1)-dimensional breaking soliton equation. Based on a special ansätz functions and the bilinear form, some entirely new double-periodic soliton solutions for the (2+1)-dimensional breaking soliton equation are presented. With the help of symbolic computation software Mathematica, many important and interesting properties for these obtained solutions are revealed with some figures. Supported by National Natural Science Foundation of China under Grant No. 61377067

Special Effects and Their Perhaps Unusual Use in Educational Television.

ERIC Educational Resources Information Center

Abouaf, Gerald

The role of the British Broadcasting Corporation (BBC) in supplying television educators with teacher aids, models, and devices is described in this report, which emphasizes the work of special effects or visual effects technicians and explains how difficult concepts and principles can be demonstrated through the use of three-dimensional models,…

The Link between Peer Relations, Prosocial Behavior, and ODD/ADHD Symptoms in 7-9-Year-Old Children.

PubMed

Paap, Muirne C S; Haraldsen, Ira R; Breivik, Kyrre; Butcher, Phillipa R; Hellem, Frøydis M; Stormark, Kjell M

2013-01-01

Oppositional defiant disorder (ODD) and attention-deficit/hyperactivity disorder (ADHD) are characterized by symptoms that hinder successful positive interaction with peers. The main goal of this study was to examine if the presence of symptoms of ODD and ADHD affects the relationship between positive social behavior and peer status found in 7-9-year-old children who show symptoms typical of ADHD and/or ODD. Furthermore, the possible interaction with sex was investigated. We used data collected in the first wave of The Bergen Child Study of mental health (BCS), a prospective longitudinal total population study of children's developmental and mental health. The target population consisted of children in the second to the fourth, in all public, private, and special schools in Bergen, Norway, in the fall of 2002 (N = 9430). All 79 primary schools in Bergen participated in the study. Both teacher (8809 complete cases) and parent (6253 complete cases) report were used in the analyses. ADHD and ODD scores were estimated using the Swanson Noland and Pelham rating scale version IV (SNAP-IV), and peer problems and prosocial behavior were assessed using the Strengths and Difficulties Questionnaire (SDQ). We replicated the relationship between peer problems and prosocial behavior found previously in typically developing children. Our results showed that the relationship between peer problems and prosocial behavior became weaker as the ODD symptoms increased in number and severity. For ADHD this effect was only found in the teacher report of the children. A sex effect for ODD symptoms was found only using the parent report: boys with ODD symptoms showed less prosocial behavior than girls with similar levels of ODD symptoms. Since this effect was not found using the teacher data, it may imply a situational effect (school/home) for girls with high levels of ODD. The moderator effect of ODD/ADHD was comparable for boys and girls. Our findings suggest that even if children with ADHD/ODD symptoms have the opportunity to practice their social skills in peer relationships, this is not necessarily accompanied by an increase in prosocial behavior.

The Link between Peer Relations, Prosocial Behavior, and ODD/ADHD Symptoms in 7–9-Year-Old Children

PubMed Central

Paap, Muirne C. S.; Haraldsen, Ira R.; Breivik, Kyrre; Butcher, Phillipa R.; Hellem, Frøydis M.; Stormark, Kjell M.

2013-01-01

Oppositional defiant disorder (ODD) and attention-deficit/hyperactivity disorder (ADHD) are characterized by symptoms that hinder successful positive interaction with peers. The main goal of this study was to examine if the presence of symptoms of ODD and ADHD affects the relationship between positive social behavior and peer status found in 7–9-year-old children who show symptoms typical of ADHD and/or ODD. Furthermore, the possible interaction with sex was investigated. We used data collected in the first wave of The Bergen Child Study of mental health (BCS), a prospective longitudinal total population study of children's developmental and mental health. The target population consisted of children in the second to the fourth, in all public, private, and special schools in Bergen, Norway, in the fall of 2002 (N = 9430). All 79 primary schools in Bergen participated in the study. Both teacher (8809 complete cases) and parent (6253 complete cases) report were used in the analyses. ADHD and ODD scores were estimated using the Swanson Noland and Pelham rating scale version IV (SNAP-IV), and peer problems and prosocial behavior were assessed using the Strengths and Difficulties Questionnaire (SDQ). We replicated the relationship between peer problems and prosocial behavior found previously in typically developing children. Our results showed that the relationship between peer problems and prosocial behavior became weaker as the ODD symptoms increased in number and severity. For ADHD this effect was only found in the teacher report of the children. A sex effect for ODD symptoms was found only using the parent report: boys with ODD symptoms showed less prosocial behavior than girls with similar levels of ODD symptoms. Since this effect was not found using the teacher data, it may imply a situational effect (school/home) for girls with high levels of ODD. The moderator effect of ODD/ADHD was comparable for boys and girls. Our findings suggest that even if children with ADHD/ODD symptoms have the opportunity to practice their social skills in peer relationships, this is not necessarily accompanied by an increase in prosocial behavior. PMID:24286065

Breast-feeding and infant illness: a dose-response relationship?

PubMed Central

Raisler, J; Alexander, C; O'Campo, P

1999-01-01

OBJECTIVES: The purpose of this study was to determine whether breast-feeding has a dose-related protective effect against illness and whether it confers special health benefits to poor infants. METHODS: The association between breast-feeding dose and illnesses in the first 6 months of life was analyzed with generalized estimating equations regression for 7092 infants from the National Maternal and Infant Health Survey. Breast-feeding dose (ratio of breast-feedings to other feedings) was categorized as full, most, equal, less, or no breast-feeding. RESULTS: Compared with no breast-feeding, full breast-feeding infants had lower odds ratios of diarrhea, cough or wheeze, and vomiting and lower mean ratios of illness months and sick baby medical visits. Most breast-feeding infants had lower odds ratios of diarrhea and cough or wheeze, and equal breast-feeding infants had lower odds ratios of cough or wheeze. Full, most, and equal breast-feeding infants without siblings had lower odds ratios of ear infections and certain other illnesses, but those with siblings did not. Less breast-feeding infants had no reduced odds ratios of illness. Findings did not vary by income. CONCLUSIONS: Full breast-feeding was associated with the lowest illness rates. Minimal (less) breast-feeding was not protective. Breast-feeding conferred similar health benefits in all economic groups. PMID:9987460

Global constraints on Z2 fluxes in two different anisotropic limits of a hypernonagon Kitaev model

NASA Astrophysics Data System (ADS)

Kato, Yasuyuki; Kamiya, Yoshitomo; Nasu, Joji; Motome, Yukitoshi

2018-05-01

The Kitaev model is an exactly-soluble quantum spin model, whose ground state provides a canonical example of a quantum spin liquid. Spin excitations from the ground state are fractionalized into emergent matter fermions and Z2 fluxes. The Z2 flux excitation is pointlike in two dimensions, while it comprises a closed loop in three dimensions because of the local constraint for each closed volume. In addition, the fluxes obey global constraints involving (semi)macroscopic number of fluxes. We here investigate such global constraints in the Kitaev model on a three-dimensional lattice composed of nine-site elementary loops, dubbed the hypernonagon lattice, whose ground state is a chiral spin liquid. We consider two different anisotropic limits of the hypernonagon Kitaev model where the low-energy effective models are described solely by the Z2 fluxes. We show that there are two kinds of global constraints in the model defined on a three-dimensional torus, namely, surface and volume constraints: the surface constraint is imposed on the even-odd parity of the total number of fluxes threading a two-dimensional slice of the system, while the volume constraint is for the even-odd parity of the number of the fluxes through specific plaquettes whose total number is proportional to the system volume. In the two anisotropic limits, therefore, the elementary excitation of Z2 fluxes occurs in a pair of closed loops so as to satisfy both two global constraints as well as the local constraints.

Spekkens’ toy model in all dimensions and its relationship with stabiliser quantum mechanics

NASA Astrophysics Data System (ADS)

Catani, Lorenzo; E Browne, Dan

2017-07-01

Spekkens’ toy model is a non-contextual hidden variable model with an epistemic restriction, a constraint on what an observer can know about reality. The aim of the model, developed for continuous and discrete prime degrees of freedom, is to advocate the epistemic view of quantum theory, where quantum states are states of incomplete knowledge about a deeper underlying reality. Many aspects of quantum mechanics and protocols from quantum information can be reproduced in the model. In spite of its significance, a number of aspects of Spekkens’ model remained incomplete. Formal rules for the update of states after measurement had not been written down, and the theory had only been constructed for prime-dimensional and infinite dimensional systems. In this work, we remedy this, by deriving measurement update rules and extending the framework to derive models in all dimensions, both prime and non-prime. Stabiliser quantum mechanics (SQM) is a sub-theory of quantum mechanics with restricted states, transformations and measurements. First derived for the purpose of constructing error correcting codes, it now plays a role in many areas of quantum information theory. Previously, it had been shown that Spekkens’ model was operationally equivalent to SQM in the case of odd prime dimensions. Here, exploiting known results on Wigner functions, we extend this to show that Spekkens’ model is equivalent to SQM in all odd dimensions, prime and non-prime. This equivalence provides new technical tools for the study of technically difficult compound-dimensional SQM.

Majorana zero modes in the hopping-modulated one-dimensional p-wave superconducting model.

PubMed

Gao, Yi; Zhou, Tao; Huang, Huaixiang; Huang, Ran

2015-11-20

We investigate the one-dimensional p-wave superconducting model with periodically modulated hopping and show that under time-reversal symmetry, the number of the Majorana zero modes (MZMs) strongly depends on the modulation period. If the modulation period is odd, there can be at most one MZM. However if the period is even, the number of the MZMs can be zero, one and two. In addition, the MZMs will disappear as the chemical potential varies. We derive the condition for the existence of the MZMs and show that the topological properties in this model are dramatically different from the one with periodically modulated potential.

Contextuality as a Resource for Models of Quantum Computation with Qubits

NASA Astrophysics Data System (ADS)

Bermejo-Vega, Juan; Delfosse, Nicolas; Browne, Dan E.; Okay, Cihan; Raussendorf, Robert

2017-09-01

A central question in quantum computation is to identify the resources that are responsible for quantum speed-up. Quantum contextuality has been recently shown to be a resource for quantum computation with magic states for odd-prime dimensional qudits and two-dimensional systems with real wave functions. The phenomenon of state-independent contextuality poses a priori an obstruction to characterizing the case of regular qubits, the fundamental building block of quantum computation. Here, we establish contextuality of magic states as a necessary resource for a large class of quantum computation schemes on qubits. We illustrate our result with a concrete scheme related to measurement-based quantum computation.

Equivalent D = 3 supergravity amplitudes from double copies of three-algebra and two-algebra gauge theories.

PubMed

Huang, Yu-tin; Johansson, Henrik

2013-04-26

We show that three-dimensional supergravity amplitudes can be obtained as double copies of either three-algebra super-Chern-Simons matter theory or two-algebra super-Yang-Mills theory when either theory is organized to display the color-kinematics duality. We prove that only helicity-conserving four-dimensional gravity amplitudes have nonvanishing descendants when reduced to three dimensions, implying the vanishing of odd-multiplicity S-matrix elements, in agreement with Chern-Simons matter theory. We explicitly verify the double-copy correspondence at four and six points for N = 12,10,8 supergravity theories and discuss its validity for all multiplicity.

AdS3 to dS3 transition in the near horizon of asymptotically de Sitter solutions

NASA Astrophysics Data System (ADS)

Sadeghian, S.; Vahidinia, M. H.

2017-08-01

We consider two solutions of Einstein-Λ theory which admit the extremal vanishing horizon (EVH) limit, odd-dimensional multispinning Kerr black hole (in the presence of cosmological constant) and cosmological soliton. We show that the near horizon EVH geometry of Kerr has a three-dimensional maximally symmetric subspace whose curvature depends on rotational parameters and the cosmological constant. In the Kerr-dS case, this subspace interpolates between AdS3 , three-dimensional flat and dS3 by varying rotational parameters, while the near horizon of the EVH cosmological soliton always has a dS3 . The feature of the EVH cosmological soliton is that it is regular everywhere on the horizon. In the near EVH case, these three-dimensional parts turn into the corresponding locally maximally symmetric spacetimes with a horizon: Kerr-dS3 , flat space cosmology or BTZ black hole. We show that their thermodynamics match with the thermodynamics of the original near EVH black holes. We also briefly discuss the holographic two-dimensional CFT dual to the near horizon of EVH solutions.

Two- and Three-Dimensional Probes of Parity in Primordial Gravity Waves.

PubMed

Masui, Kiyoshi Wesley; Pen, Ue-Li; Turok, Neil

2017-06-02

We show that three-dimensional information is critical to discerning the effects of parity violation in the primordial gravity-wave background. If present, helical gravity waves induce parity-violating correlations in the cosmic microwave background (CMB) between parity-odd polarization B modes and parity-even temperature anisotropies (T) or polarization E modes. Unfortunately, EB correlations are much weaker than would be naively expected, which we show is due to an approximate symmetry resulting from the two-dimensional nature of the CMB. The detectability of parity-violating correlations is exacerbated by the fact that the handedness of individual modes cannot be discerned in the two-dimensional CMB, leading to a noise contribution from scalar matter perturbations. In contrast, the tidal imprints of primordial gravity waves fossilized into the large-scale structure of the Universe are a three-dimensional probe of parity violation. Using such fossils the handedness of gravity waves may be determined on a mode-by-mode basis, permitting future surveys to probe helicity at the percent level if the amplitude of primordial gravity waves is near current observational upper limits.

Full-dimensional quantum mechanics calculations for the spectroscopic characterization of the isomerization transition states of HOCO/DOCO systems.

PubMed

Ma, Dandan; Ren, Haisheng; Ma, Jianyi

2018-02-14

Full-dimensional quantum mechanics calculations were performed to determine the vibrational energy levels of HOCO and DOCO based on an accurate potential energy surface. Almost all of the vibrational energy levels up to 3500 cm -1 from the vibrational ground state were assigned, and the calculated energy levels in this work are well in agreement with the reported results by Bowman. The corresponding full dimensional wavefunctions present some special features. When the energy level approaches the barrier height, the trans-HOCO and cis-HOCO states strongly couple through tunneling interactions, and the tunneling interaction and Fermi resonance were observed in the DOCO system. The energy level patterns of trans-HOCO, cis-HOCO and trans-DOCO provide a reasonable fitted barrier height using the fitting formula of Field et al., however, a discrepancy exists for the cis-DOCO species which is considered as a random event. Our full-dimensional calculations give positive evidence for the accuracy of the spectroscopic characterization model of the isomerization transition state reported by Field et al., which was developed from one-dimensional model systems. Furthermore, the special case of cis-DOCO in this work means that the isotopic substitution can solve the problem of the accidental failure of Field's spectroscopic characterization model.

On the motion of one-dimensional double pendulum

NASA Astrophysics Data System (ADS)

Burian, S. N.; Kalnitsky, V. S.

2018-05-01

A two-dimensional dynamic Lagrangian system of a double mathematical pendulum with one special constraint is considered. Configuration spaces for a given constraints (ellipses) are studied. The diagrams of paths and reactions in the course of motion along them are shown. The calculations of the transversal intersection case and in the case of tangency are given.

Nonlinear optical effects of opening a gap in graphene

NASA Astrophysics Data System (ADS)

Carvalho, David N.; Biancalana, Fabio; Marini, Andrea

2018-05-01

Graphene possesses remarkable electronic, optical, and mechanical properties that have taken the research of two-dimensional relativistic condensed matter systems to prolific levels. However, the understanding of how its nonlinear optical properties are affected by relativisticlike effects has been broadly uncharted. It has been recently shown that highly nontrivial currents can be generated in free-standing samples, notably leading to the generation of even harmonics. Since graphene monolayers are centrosymmetric media, for which such harmonic generation at normal incidence is deemed inaccessible, this light-driven phenomenon is both startling and promising. More realistically, graphene samples are often deposited on a dielectric substrate, leading to additional intricate interactions. Here, we present a treatment to study this instance by gapping the spectrum and we show this leads to the appearance of a Berry phase in the carrier dynamics. We analyze the role of such a phase in the generated nonlinear current and conclude that it suppresses odd-harmonic generation. The pump energy can be tuned to the energy gap to yield interference among odd harmonics mediated by interband transitions, allowing even harmonics to be generated. Our results and general methodology pave the way for understanding the role of gap opening in the nonlinear optics of two-dimensional lattices.

Referenceless one-dimensional Nyquist ghost correction in multicoil single-shot spatiotemporally encoded MRI.

PubMed

Chen, Ying; Liao, Yupeng; Yuan, Lisha; Liu, Hui; Yun, Seong Dae; Shah, Nadim Joni; Chen, Zhong; Zhong, Jianhui

2017-04-01

Single-shot spatiotemporally encoded (SPEN) MRI is a novel fast imaging method capable of retaining the time efficiency of single-shot echo planar imaging (EPI) but with distortion artifacts significantly reduced. Akin to EPI, the phase inconsistencies between mismatched even and odd echoes also result in the so-called Nyquist ghosts. However, the characteristic of the SPEN signals provides the possibility of obtaining ghost-free images directly from even and odd echoes respectively, without acquiring additional reference scans. In this paper, a theoretical analysis of the Nyquist ghosts manifested in single-shot SPEN MRI is presented, a one-dimensional correction scheme is put forward capable of maintaining definition of image features without blurring when the phase inconsistency along SPEN encoding direction is negligible, and a technique is introduced for convenient and robust correction of data from multi-channel receiver coils. The effectiveness of the proposed processing pipeline is validated by a series of experiments conducted on simulation data, in vivo rats and healthy human brains. The robustness of the method is further verified by implementing distortion correction on ghost corrected data. Copyright © 2016. Published by Elsevier Inc.

High-harmonic generation from an atomically thin semiconductor [Observation of high harmonics from an atomically thin semiconductor

DOE PAGES

Liu, Hanzhe; Li, Yilei; You, Yong Sing; ...

2016-11-14

High-harmonic generation (HHG) in bulk solids permits the exploration of materials in a new regime of strong fields and attosecond timescales. The generation process has been discussed in the context of strongly driven electron dynamics in single-particle bands. Two-dimensional materials exhibit distinctive electronic properties compared to the bulk that could significantly modify the HHG process, including different symmetries, access to individual valleys and enhanced many-body interactions. Here we demonstrate non-perturbative HHG from a monolayer MoS 2 crystal, with even and odd harmonics extending to the 13th order. The even orders are predominantly polarized perpendicular to the pump and are compatiblemore » with the anomalous transverse intraband current arising from the material’s Berry curvature, while the weak parallel component suggests the importance of interband transitions. The odd harmonics exhibit a significant enhancement in efficiency per layer compared to the bulk, which is attributed to correlation effects. In conclusion, the combination of strong many-body Coulomb interactions and widely tunable electronic properties in two-dimensional materials offers a new platform for attosecond physics.« less

Density-functional theory study of the geometries, stabilities, and electronic properties of Au n Rb (n = 1-10) clusters: comparison with pure gold clusters

NASA Astrophysics Data System (ADS)

Hu, Yan-Fei; Jiang, Gang; Meng, Da-Qiao

2012-01-01

The density functional method with the relativistic effective core potential has been employed to investigate systematically the geometric structures, relative stabilities, growth-pattern behavior, and electronic properties of small bimetallic Au n Rb (n = 1-10) and pure gold Au n (n ≤ 11) clusters. For the geometric structures of the Au n Rb (n = 1-10) clusters, the dominant growth pattern is for a Rb-substituted Au n +1 cluster or one Au atom capped on a Au n -1Rb cluster, and the turnover point from a two-dimensional to a three-dimensional structure occurs at n = 4. Moreover, the stability of the ground-state structures of these clusters has been examined via an analysis of the average atomic binding energies, fragmentation energies, and the second-order difference of energies as a function of cluster size. The results exhibit a pronounced even-odd alternation phenomenon. The same pronounced even-odd alternations are found for the HOMO-LUMO gap, VIPs, VEAs, and the chemical hardness. In addition, about one electron charge transfers from the Au n host to the Rb atom in each corresponding Au n Rb cluster.

The importance of energetic particle precipitation on the chemical composition of the middle atmosphere

NASA Technical Reports Server (NTRS)

Thorne, R. M.

1980-01-01

The present review deals with the importance of three distinct classes of precipitation which directly deposit energy into the middle atmosphere, viz. galactic cosmic radiation, energetic solar protons and relativistic electron precipitation from the earth's radiation belts. Chemical considerations during particle precipitation are discussed, with special emphasis on the relative production rate of odd nitrogen and odd hydrogen species during ionizing particle precipitation. The long residence time of NO in the upper stratosphere, where catalytic interaction with O3 is most effective, requires that this mechanism be included in future modeling of global distribution of O3. Other situations causing O3 depletion are also identified.

A three-dimensional Dirichlet-to-Neumann operator for water waves over topography

NASA Astrophysics Data System (ADS)

Andrade, D.; Nachbin, A.

2018-06-01

Surface water waves are considered propagating over highly variable non-smooth topographies. For this three dimensional problem a Dirichlet-to-Neumann (DtN) operator is constructed reducing the numerical modeling and evolution to the two dimensional free surface. The corresponding Fourier-type operator is defined through a matrix decomposition. The topographic component of the decomposition requires special care and a Galerkin method is provided accordingly. One dimensional numerical simulations, along the free surface, validate the DtN formulation in the presence of a large amplitude, rapidly varying topography. An alternative, conformal mapping based, method is used for benchmarking. A two dimensional simulation in the presence of a Luneburg lens (a particular submerged mound) illustrates the accurate performance of the three dimensional DtN operator.

Calculation of compressible flow in and about three-dimensional inlets with and without auxiliary inlets by a higher-order panel method

NASA Technical Reports Server (NTRS)

Hess, J. L.; Friedman, D. M.

1982-01-01

A three dimensional higher order panel method was specialized to the case of inlets with auxiliary inlets. The resulting program has a number of graphical input-output features to make it highly useful to the designer. The various aspects of the program are described instructions for its use are presented.

Color image segmentation to detect defects on fresh ham

NASA Astrophysics Data System (ADS)

Marty-Mahe, Pascale; Loisel, Philippe; Brossard, Didier

2003-04-01

We present in this paper the color segmentation methods that were used to detect appearance defects on 3 dimensional shape of fresh ham. The use of color histograms turned out to be an efficient solution to characterize the healthy skin, but a special care must be taken to choose the color components because of the 3 dimensional shape of ham.

Teachers' Perceptions of the Benefits and Challenges of Three-Dimensional Virtual Worlds for Social Skills Practice

ERIC Educational Resources Information Center

Nussli, Natalie; Oh, Kevin

2016-01-01

This case study describes how a systematic 7-Step Virtual Worlds Teacher Training Workshop guided the enculturation of 18 special education teachers into three-dimensional virtual worlds. The main purpose was to enable these teachers to make informed decisions about the usability of virtual worlds for students with social skills challenges, such…

Solution of Radiation and Convection Heat-Transfer Problems

NASA Technical Reports Server (NTRS)

Oneill, R. F.

1986-01-01

Computer program P5399B developed to accommodate variety of fin-type heat conduction applications involving radiative or convective boundary conditions with additionally imposed local heat flux. Program also accommodates significant variety of one-dimensional heat-transfer problems not corresponding specifically to fin-type applications. Program easily accommodates all but few specialized one-dimensional heat-transfer analyses as well as many twodimensional analyses.

Odd Man Out: How Government Supports Private-Sector Innovation, Except in Education. Private Enterprise in American Education. Special Report 3

ERIC Educational Resources Information Center

Bailey, John

2011-01-01

For decades, for-profit educational provision has been merely tolerated, often grudgingly. In the world of charter schooling, for-profit providers are lambasted and sometimes prohibited. In higher education, for-profit institutions have grown rapidly, enrolling millions of nontraditional students and earning enmity, suspicion, and now…

Unmet Health Care Needs in Children with Cerebral Palsy: A Cross-Sectional Study

ERIC Educational Resources Information Center

Jackson, Katie E.; Krishnaswami, Shanthi; McPheeters, Melissa

2011-01-01

Children with potentially severe health conditions such as cerebral palsy (CP) are at risk for unmet health care needs. We sought to determine whether children with CP had significantly greater unmet health care needs than children with other special health care needs (SHCN), and whether conditions associated with CP increased the odds of unmet…

The Signs of a Savant: Language Against the Odds

ERIC Educational Resources Information Center

Smith, Neil; Tsimpli, Ianthi; Morgan, Gary; Woll, Bencie

2011-01-01

Every once in a while nature gives us insight into the human condition by providing us with a unique case whose special properties illuminate the species as a whole. Christopher is such an example. Despite disabilities which mean that everyday tasks are burdensome chores, Christopher is a linguistic wonder who can read, write, speak, understand…

Glimmers of a Quantum KAM Theorem: Insights from Quantum Quenches in One-Dimensional Bose Gases

DOE PAGES

Brandino, G. P.; Caux, J. -S.; Konik, R. M.

2015-12-16

Real-time dynamics in a quantum many-body system are inherently complicated and hence difficult to predict. There are, however, a special set of systems where these dynamics are theoretically tractable: integrable models. Such models possess non-trivial conserved quantities beyond energy and momentum. These quantities are believed to control dynamics and thermalization in low dimensional atomic gases as well as in quantum spin chains. But what happens when the special symmetries leading to the existence of the extra conserved quantities are broken? Is there any memory of the quantities if the breaking is weak? Here, in the presence of weak integrability breaking,more » we show that it is possible to construct residual quasi-conserved quantities, so providing a quantum analog to the KAM theorem and its attendant Nekhoreshev estimates. We demonstrate this construction explicitly in the context of quantum quenches in one-dimensional Bose gases and argue that these quasi-conserved quantities can be probed experimentally.« less

Reductions in finite-dimensional integrable systems and special points of classical r-matrices

NASA Astrophysics Data System (ADS)

Skrypnyk, T.

2016-12-01

For a given 𝔤 ⊗ 𝔤-valued non-skew-symmetric non-dynamical classical r-matrices r(u, v) with spectral parameters, we construct the general form of 𝔤-valued Lax matrices of finite-dimensional integrable systems satisfying linear r-matrix algebra. We show that the reduction in the corresponding finite-dimensional integrable systems is connected with "the special points" of the classical r-matrices in which they become degenerated. We also propose a systematic way of the construction of additional integrals of the Lax-integrable systems associated with the symmetries of the corresponding r-matrices. We consider examples of the Lax matrices and integrable systems that are obtained in the framework of the general scheme. Among them there are such physically important systems as generalized Gaudin systems in an external magnetic field, ultimate integrable generalization of Toda-type chains (including "modified" or "deformed" Toda chains), generalized integrable Jaynes-Cummings-Dicke models, integrable boson models generalizing Bose-Hubbard dimer models, etc.

Comparison of obesity among Chinese and U.S. Special Olympic athletes with intellectual disabilities.

PubMed

Li, H; Frey, G C; McCormick, B P; Johnston, J D

2015-01-01

Obesity is a health problem in China, but there are no reports on the obesity status of Chinese citizens with intellectual disabilities (ID). Research has shown that adults with ID have higher body mass index (BMI) than adults without ID, but this information is primarily based on populations residing in North American and European countries. The purpose of this study was to compare BMI and obesity status of Chinese and U.S. Special Olympic athletes with ID. Height, weight, BMI and self-reported physical activity (SRPA) data from the Special Olympics 2006 U.S. National Games and 2007 Shanghai World Games databases were analyzed. Linear and logistic analyses were conducted for continuous data and dichotomous variables, respectively. Predictor variables were age, gender, country, SRPA, and obesity status according to country specific criteria. Significance was set at p < 0.05. The U.S. group had significantly higher BMI values than their Chinese counterparts. Age (p = 0.001) and country (p = <0.001) were the main predictors of BMI and obesity status, even when country-specific standards of obesity classifications were used. Holding all other factors constant, each unit increase of age was associated with increased odds for obesity by a factor of 1.04 and the odds of obesity occurring in U.S. athletes was 2.47 times greater than in Chinese athletes. Obesity is an emerging health problem for Chinese adults with ID. Participation in Special Olympics does not offset obesity in people with ID and other methods of intervention are needed to address obesity in this population segment. This is a global health concern that requires immediate attention. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mental health care use in medically unexplained and explained physical symptoms: findings from a general population study

PubMed Central

van Eck van der Sluijs, Jonna F; ten Have, Margreet; Rijnders, Cees A; van Marwijk, Harm WJ; de Graaf, Ron; van der Feltz-Cornelis, Christina M

2016-01-01

Objective The aim of this study was to explore mental health care utilization patterns in primary and specialized mental health care of people with unexplained or explained physical symptoms. Methods Data were derived from the first wave of the Netherlands Mental Health Survey and Incidence Study-2, a nationally representative face-to-face cohort study among the general population aged 18–64 years. We selected subjects with medically unexplained symptoms (MUS) only (MUSonly; n=177), explained physical symptoms only (PHYonly, n=1,952), combined MUS and explained physical symptoms (MUS + PHY, n=209), and controls without physical symptoms (NONE, n=4,168). We studied entry into mental health care and the number of treatment contacts for mental problems, in both primary care and specialized mental health care. Analyses were adjusted for sociodemographic characteristics and presence of any 12-month mental disorder assessed with the Composite International Diagnostic Interview 3.0. Results At the primary care level, all three groups of subjects with physical symptoms showed entry into care for mental health problems significantly more often than controls. The adjusted odds ratios were 2.29 (1.33, 3.95) for MUSonly, 1.55 (1.13, 2.12) for PHYonly, and 2.25 (1.41, 3.57) for MUS + PHY. At the specialized mental health care level, this was the case only for MUSonly subjects (adjusted odds ratio 1.65 [1.04, 2.61]). In both the primary and specialized mental health care, there were no significant differences between the four groups in the number of treatment contacts once they entered into treatment. Conclusion All sorts of physical symptoms, unexplained as well as explained, were associated with significant higher entry into primary care for mental problems. In specialized mental health care, this was true only for MUSonly. No differences were found in the number of treatment contacts. This warrants further research aimed at the content of the treatment contacts. PMID:27574433

On the number of multiplications necessary to compute a length-2 exp n DFT

NASA Technical Reports Server (NTRS)

Heideman, M. T.; Burrus, C. S.

1986-01-01

The number of multiplications necessary and sufficient to compute a length-2 exp n DFT is determined. The method of derivation is shown to apply to the multiplicative complexity results of Winograd (1980, 1981) for a length-p exp n DFT, for p an odd prime number. The multiplicative complexity of the one-dimensional DFT is summarized for many possible lengths.

On a 3-D singularity element for computation of combined mode stress intensities

NASA Technical Reports Server (NTRS)

Atluri, S. N.; Kathiresan, K.

1976-01-01

A special three-dimensional singularity element is developed for the computation of combined modes 1, 2, and 3 stress intensity factors, which vary along an arbitrarily curved crack front in three dimensional linear elastic fracture problems. The finite element method is based on a displacement-hybrid finite element model, based on a modified variational principle of potential energy, with arbitrary element interior displacements, interelement boundary displacements, and element boundary tractions as variables. The special crack-front element used in this analysis contains the square root singularity in strains and stresses, where the stress-intensity factors K(1), K(2), and K(3) are quadratically variable along the crack front and are solved directly along with the unknown nodal displacements.

Pions as gluons in higher dimensions

NASA Astrophysics Data System (ADS)

Cheung, Clifford; Remmen, Grant N.; Shen, Chia-Hsien; Wen, Congkao

2018-04-01

We derive the nonlinear sigma model as a peculiar dimensional reduction of Yang-Mills theory. In this framework, pions are reformulated as higher-dimensional gluons arranged in a kinematic configuration that only probes cubic interactions. This procedure yields a purely cubic action for the nonlinear sigma model that exhibits a symmetry enforcing color-kinematics duality. Remarkably, the associated kinematic algebra originates directly from the Poincaré algebra in higher dimensions. Applying the same construction to gravity yields a new quartic action for Born-Infeld theory and, applied once more, a cubic action for the special Galileon theory. Since the nonlinear sigma model and special Galileon are subtly encoded in the cubic sectors of Yang-Mills theory and gravity, respectively, their double copy relationship is automatic.

G-Strands on symmetric spaces

PubMed Central

2017-01-01

We study the G-strand equations that are extensions of the classical chiral model of particle physics in the particular setting of broken symmetries described by symmetric spaces. These equations are simple field theory models whose configuration space is a Lie group, or in this case a symmetric space. In this class of systems, we derive several models that are completely integrable on finite dimensional Lie group G, and we treat in more detail examples with symmetric space SU(2)/S1 and SO(4)/SO(3). The latter model simplifies to an apparently new integrable nine-dimensional system. We also study the G-strands on the infinite dimensional group of diffeomorphisms, which gives, together with the Sobolev norm, systems of 1+2 Camassa–Holm equations. The solutions of these equations on the complementary space related to the Witt algebra decomposition are the odd function solutions. PMID:28413343

Spin-triplet superconductivity in a weak-coupling Hubbard model for the quasi-one-dimensional compound Li0.9Mo6O17

NASA Astrophysics Data System (ADS)

Cho, Weejee; Platt, Christian; McKenzie, Ross H.; Raghu, Srinivas

2015-10-01

The purple bronze Li0.9Mo6O17 is of interest due to its quasi-one-dimensional electronic structure and the possible Luttinger liquid behavior resulting from it. For sufficiently low temperatures, it is a superconductor with a pairing symmetry that is still to be determined. To shed light on this issue, we analyze a minimal Hubbard model for this material involving four molybdenum orbitals per unit cell near quarter filling, using asymptotically exact perturbative renormalization group methods. We find that spin-triplet odd-parity superconductivity is the dominant instability. Approximate nesting properties of the two quasi-one-dimensional Fermi surfaces enhance certain second-order processes, which play crucial roles in determining the structure of the pairing gap. Notably, we find that the gap has more sign changes than required by the point-group symmetry.

Spin triplet superconductivity in a weak-coupling Hubbard model for the quasi-one-dimensional compound Li0.9 Mo6 O17

NASA Astrophysics Data System (ADS)

Platt, Christian; Cho, Weejee; McKenzie, Ross H.; Raghu, Sri

The purple bronze Li0.9Mo6O17 is of interest due to its quasi-one-dimensional electronic structure and the possible Luttinger liquid behavior resulting from it. For sufficiently low temperatures, it is a superconductor with a pairing symmetry that is still to be determined. To shed light on this issue, we analyze a minimal Hubbard model for this material involving four Molybdenum orbitals per unit cell near quarter filling, using asymptotically exact perturbative renormalization group methods. We find that spin triplet odd-parity superconductivity is the dominant instability. Approximate nesting properties of the two quasi-one-dimensional Fermi surfaces enhance certain second-order processes, which play crucial roles in determining the structure of the pairing gap. Notably, we find that the gap has accidental nodes, i.e. it has more sign changes than required by the point-group symmetry.

Existence of Lipschitz selections of the Steiner map

NASA Astrophysics Data System (ADS)

Bednov, B. B.; Borodin, P. A.; Chesnokova, K. V.

2018-02-01

This paper is concerned with the problem of the existence of Lipschitz selections of the Steiner map {St}_n, which associates with n points of a Banach space X the set of their Steiner points. The answer to this problem depends on the geometric properties of the unit sphere S(X) of X, its dimension, and the number n. For n≥slant 4 general conditions are obtained on the space X under which {St}_n admits no Lipschitz selection. When X is finite dimensional it is shown that, if n≥slant 4 is even, the map {St}_n has a Lipschitz selection if and only if S(X) is a finite polytope; this is not true if n≥slant 3 is odd. For n=3 the (single-valued) map {St}_3 is shown to be Lipschitz continuous in any smooth strictly-convex two-dimensional space; this ceases to be true in three-dimensional spaces. Bibliography: 21 titles.

Special Issue: 3D Printing for Biomedical Engineering.

PubMed

Chua, Chee Kai; Yeong, Wai Yee; An, Jia

2017-02-28

Three-dimensional (3D) printing has a long history of applications in biomedical engineering. The development and expansion of traditional biomedical applications are being advanced and enriched by new printing technologies. New biomedical applications such as bioprinting are highly attractive and trendy. This Special Issue aims to provide readers with a glimpse of the recent profile of 3D printing in biomedical research.

Associations between state economic and health systems capacities and service use by children with special health care needs.

PubMed

Margolis, Lewis H; Mayer, Michelle; Clark, Kathryn A; Farel, Anita M

2011-08-01

To examine the relationship between measures of state economic, political, health services, and Title V capacity and individual level measures of the well-being of CSHCN. We selected five measures of Title V capacity from the Title V Information System and 13 state capacity measures from a variety of data sources, and eight indicators of intermediate health outcomes from the National Survey of Children with Special Health Care Needs. To assess the associations between Title V capacity and health services outcomes, we used stepwise regression to identify significant capacity measures while accounting for the survey design and clustering of observations by state. To assess the associations between economic, political and health systems capacity and health outcomes we fit weighted logistic regression models for each outcome, using a stepwise procedure to reduce the models. Using statistically significant capacity measures from the stepwise models, we fit reduced random effects logistic regression models to account for clustering of observations by state. Few measures of Title V and state capacity were associated with health services outcomes. For health systems measures, a higher percentage of uninsured children was associated with decreased odds of receipt of early intervention services, decreased odds of receipt of professional care coordination, and increased odds of delayed or missed care. Parents in states with higher per capita Medicaid expenditures on children were more likely to report receipt of special education services. Only two state capacity measures were associated explicitly with Title V: states with higher generalist physician to population ratios were associated with a greater likelihood of parent report of having heard of Title V and states with higher per capita gross state product were less likely to be associated with a report of using Title V services, conditional on having heard of Title V. The state level measure of family participation in Title V governance was negatively associated with receipt of care coordination and having used Title V services. The measures of state economic, political, health systems, and Title V capacity that we have analyzed are only weakly associated with the well-being of children with special health care needs. If Congress and other policymakers increase the expectations of the states in assuring that the needs of CSHCN and their families are addressed, it is essential to be cognizant of the capacities of the states to undertake that role.

Mixing times in quantum walks on two-dimensional grids

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

Marquezino, F. L.; Portugal, R.; Abal, G.

2010-10-15

Mixing properties of discrete-time quantum walks on two-dimensional grids with toruslike boundary conditions are analyzed, focusing on their connection to the complexity of the corresponding abstract search algorithm. In particular, an exact expression for the stationary distribution of the coherent walk over odd-sided lattices is obtained after solving the eigenproblem for the evolution operator for this particular graph. The limiting distribution and mixing time of a quantum walk with a coin operator modified as in the abstract search algorithm are obtained numerically. On the basis of these results, the relation between the mixing time of the modified walk and themore » running time of the corresponding abstract search algorithm is discussed.« less

Mixing times in quantum walks on two-dimensional grids

NASA Astrophysics Data System (ADS)

Marquezino, F. L.; Portugal, R.; Abal, G.

2010-10-01

Mixing properties of discrete-time quantum walks on two-dimensional grids with toruslike boundary conditions are analyzed, focusing on their connection to the complexity of the corresponding abstract search algorithm. In particular, an exact expression for the stationary distribution of the coherent walk over odd-sided lattices is obtained after solving the eigenproblem for the evolution operator for this particular graph. The limiting distribution and mixing time of a quantum walk with a coin operator modified as in the abstract search algorithm are obtained numerically. On the basis of these results, the relation between the mixing time of the modified walk and the running time of the corresponding abstract search algorithm is discussed.

Accuracy versus convergence rates for a three dimensional multistage Euler code

NASA Technical Reports Server (NTRS)

Turkel, Eli

1988-01-01

Using a central difference scheme, it is necessary to add an artificial viscosity in order to reach a steady state. This viscosity usually consists of a linear fourth difference to eliminate odd-even oscillations and a nonlinear second difference to suppress oscillations in the neighborhood of steep gradients. There are free constants in these differences. As one increases the artificial viscosity, the high modes are dissipated more and the scheme converges more rapidly. However, this higher level of viscosity smooths the shocks and eliminates other features of the flow. Thus, there is a conflict between the requirements of accuracy and efficiency. Examples are presented for a variety of three-dimensional inviscid solutions over isolated wings.

Finite-dimensional linear approximations of solutions to general irregular nonlinear operator equations and equations with quadratic operators

NASA Astrophysics Data System (ADS)

Kokurin, M. Yu.

2010-11-01

A general scheme for improving approximate solutions to irregular nonlinear operator equations in Hilbert spaces is proposed and analyzed in the presence of errors. A modification of this scheme designed for equations with quadratic operators is also examined. The technique of universal linear approximations of irregular equations is combined with the projection onto finite-dimensional subspaces of a special form. It is shown that, for finite-dimensional quadratic problems, the proposed scheme provides information about the global geometric properties of the intersections of quadrics.

Three-dimensional nanostructure determination from a large diffraction data set recorded using scanning electron nanodiffraction.

PubMed

Meng, Yifei; Zuo, Jian-Min

2016-09-01

A diffraction-based technique is developed for the determination of three-dimensional nanostructures. The technique employs high-resolution and low-dose scanning electron nanodiffraction (SEND) to acquire three-dimensional diffraction patterns, with the help of a special sample holder for large-angle rotation. Grains are identified in three-dimensional space based on crystal orientation and on reconstructed dark-field images from the recorded diffraction patterns. Application to a nanocrystalline TiN thin film shows that the three-dimensional morphology of columnar TiN grains of tens of nanometres in diameter can be reconstructed using an algebraic iterative algorithm under specified prior conditions, together with their crystallographic orientations. The principles can be extended to multiphase nanocrystalline materials as well. Thus, the tomographic SEND technique provides an effective and adaptive way of determining three-dimensional nanostructures.

Socioeconomic Factors for Sports Specialization and Injury in Youth Athletes.

PubMed

Jayanthi, Neeru A; Holt, Daniel B; LaBella, Cynthia R; Dugas, Lara R

The effect of socioeconomic status (SES) on rates of sports specialization and injury among youth athletes has not been described previously. Young athletes from lower socioeconomic status will have lower rates of sports specialization and subsequently lower risk of overuse injuries. Cohort study. Level 3. Injured athletes aged 7 to 18 years were recruited from 2 hospital-based sports medicine clinics and compared with uninjured athletes presenting for sports physicals at primary care clinics between 2010 and 2013. Participants completed surveys on training patterns. Electronic medical records provided injury details as well as patient zip code, race, and health insurance type. SES was estimated from zip codes. The sample was divided into SES tertiles. Analysis of variance and multivariate regression were used for continuous variables, and multivariate logistic regression analyses were conducted to explore relationships between risk factors and injury. Of 1190 athletes surveyed, 1139 (96%) had satisfactory SES data. Compared with low-SES athletes, high-SES athletes reported more hours per week spent playing organized sports (11.2 ± 6.0 vs 10.0 ± 6.5; P = 0.02), trained more months per year in their main sport (9.7 ± 3.1 vs 7.6 ± 3.7; P < 0.01), were more often highly specialized (38.9% vs 16.6%; P < 0.01), and had increased participation in individual sports (64.8% vs 40.0%; P < 0.01). The proportion of athletes with a greater than 2:1 ratio of weekly hours in organized sports to free play increased with SES. Accounting for age and weekly organized sports hours, the odds of reporting a serious overuse injury increased with SES (odds ratio, 1.5; P < 0.01). High-SES athletes reported more serious overuse injuries than low-SES athletes, potentially due to higher rates of sports specialization, more hours per week playing organized sports, higher ratio of weekly hours in organized sports to free play, and greater participation in individual sports. As SES increases, young athletes report higher degrees of sports specialization, greater participation in individual sports, and more serious overuse injuries.

Childhood growth and development associated with need for full-time special education at school age.

PubMed

Mannerkoski, Minna; Aberg, Laura; Hoikkala, Marianne; Sarna, Seppo; Kaski, Markus; Autti, Taina; Heiskala, Hannu

2009-01-01

To explore how growth measurements and attainment of developmental milestones in early childhood reflect the need for full-time special education (SE). After stratification in this population-based study, 900 pupils in full-time SE groups (age-range 7-16 years, mean 12 years 8 months) at three levels and 301 pupils in mainstream education (age-range 7-16, mean 12 years 9 months) provided data on height and weight from birth to age 7 years and head circumference to age 1 year. Developmental screening was evaluated from age 1 month to 48 months. Statistical methods included a general linear model (growth measurements), binary logistic regression analysis (odds ratios for growth), and multinomial logistic regression analysis (odds ratios for developmental milestones). At 1 year, a 1 standard deviation score (SDS) decrease in height raised the probability of SE placement by 40%, and a 1 SDS decrease in head size by 28%. In developmental screening, during the first months of life the gross motor milestones, especially head support, differentiated the children at levels 0-3. Thereafter, the fine motor milestones and those related to speech and social skills became more important. Children whose growth is mildly impaired, though in the normal range, and who fail to attain certain developmental milestones have an increased probability for SE and thus a need for special attention when toddlers age. Similar to the growth curves, these children seem to have consistent developmental curves (patterns).

Sine-Gordon Equation in (1+2) and (1+3) dimensions: Existence and Classification of Traveling-Wave Solutions.

PubMed

Zarmi, Yair

2015-01-01

The (1+1)-dimensional Sine-Gordon equation passes integrability tests commonly applied to nonlinear evolution equations. Its kink solutions (one-dimensional fronts) are obtained by a Hirota algorithm. In higher space-dimensions, the equation does not pass these tests. Although it has been derived over the years for quite a few physical systems that have nothing to do with Special Relativity, the Sine-Gordon equation emerges as a non-linear relativistic wave equation. This opens the way for exploiting the tools of the Theory of Special Relativity. Using no more than the relativistic kinematics of tachyonic momentum vectors, from which the solutions are constructed through the Hirota algorithm, the existence and classification of N-moving-front solutions of the (1+2)- and (1+3)-dimensional equations for all N ≥ 1 are presented. In (1+2) dimensions, each multi-front solution propagates rigidly at one velocity. The solutions are divided into two subsets: Solutions whose velocities are lower than a limiting speed, c = 1, or are greater than or equal to c. To connect with concepts of the Theory of Special Relativity, c will be called "the speed of light." In (1+3)-dimensions, multi-front solutions are characterized by spatial structure and by velocity composition. The spatial structure is either planar (rotated (1+2)-dimensional solutions), or genuinely three-dimensional--branes. Planar solutions, propagate rigidly at one velocity, which is lower than, equal to, or higher than c. Branes must contain clusters of fronts whose speed exceeds c = 1. Some branes are "hybrids": different clusters of fronts propagate at different velocities. Some velocities may be lower than c but some must be equal to, or exceed, c. Finally, the speed of light cannot be approached from within the subset of slower-than-light solutions in both (1+2) and (1+3) dimensions.

Virulence-associated characteristics of Escherichia coli in urinary tract infection: a statistical analysis with special attention to type 1C fimbriation.

PubMed

Siitonen, A; Martikainen, R; Ikäheimo, R; Palmgren, J; Mäkelä, P H

1993-07-01

The relative virulence (defined as odds ratio) associated with different O and K antigens, adhesins and hemolysin production of Escherichia coli strains was assessed by separate and multivariate logistic regression analyses comparing 383 strains isolated from urine of adults with a urinary tract infection with 287 fecal strains from healthy adults; special interest was paid to evaluating the role of type 1C fimbriation. Type 1C fimbriae, found on 14% of UTI and 7% of fecal strains, were associated with O groups O2, O6, O18, and O75, with capsular type K5, with mannose-resistant (both P and non-P) adhesins, and with hemolysin production. In separate analyses, O8 (odds ratio 5.9) and O75 (9.2), capsular types other than K1 (1.9-2.1), P (2.9) and non-P mannose-resistant (17.4) adhesins, and hemolysin production (3.1) were each associated with high relative virulence compared to O1, Rough, and K1 phenotypes or lack of mannose-resistant adhesins or hemolysin. All these virulence effects were independent of type 1C fimbriation. In multivariate analysis, joint variation between factors decreased the apparent virulence-promoting effect of type 1C fimbriae, O6 antigen and hemolysin but increased that of other adhesins. Especially high relative virulence (odds ratio 404.2) was associated with the combination of O75:K5:non-P mannose-resistant adhesin identified on seven UTI but no fecal strains.

Spinors fields in co-dimension one braneworlds

NASA Astrophysics Data System (ADS)

Mendes, W. M.; Alencar, G.; Landim, R. R.

2018-02-01

In this work we analyze the zero mode localization and resonances of 1/2-spin fermions in co-dimension one Randall-Sundrum braneworld scenarios. We consider delta-like, domain walls and deformed domain walls membranes. Beyond the influence of the spacetime dimension D we also consider three types of couplings: (i) the standard Yukawa coupling with the scalar field and parameter η 1, (ii) a Yukawa-dilaton coupling with two parameters η 2 and λ and (iii) a dilaton derivative coupling with parameter h. Together with the deformation parameter s, we end up with five free parameter to be considered. For the zero mode we find that the localization is dependent of D, because the spinorial representation changes when the bulk dimensionality is odd or even and must be treated separately. For case (i) we find that in odd dimensions only one chirality can be localized and for even dimension a massless Dirac spinor is trapped over the brane. In the cases (ii) and (iii) we find that for some values of the parameters, both chiralities can be localized in odd dimensions and for even dimensions we obtain that the massless Dirac spinor is trapped over the brane. We also calculated numerically resonances for cases (ii) and (iii) by using the transfer matrix method. We find that, for deformed defects, the increasing of D induces a shift in the peaks of resonances. For a given λ with domain walls, we find that the resonances can show up by changing the spacetime dimensionality. For example, the same case in D = 5 do not induces resonances but when we consider D = 10 one peak of resonance is found. Therefore the introduction of more dimensions, diversely from the bosonic case, can change drastically the zero mode and resonances in fermion fields.

A Three-Dimensional Total Odd Nitrogen (NO(y)) Simulation During SONEX using a Stretched-Grid Chemical Transport Model

NASA Technical Reports Server (NTRS)

Allen, Dale; Pickering, Kenneth; Stenchikov, Georgiy; Thompson, Anne M.; Kondo, Yutaka

1999-01-01

The relative importance of various odd nitrogen (NOy) sources including lightning, aircraft, and surface emissions on upper tropospheric total odd nitrogen is illustrated as a first application of the three-dimensional Stretched-Grid University of Maryland/Goddard Chemical-Transport Model (SG-GCTM). The SG-GCTM has been developed to look at the effect of localized sources and/or small scale mixing processes on the large-scale or global chemical balance. For this simulation, the stretched-arid was chosen so that its maximum resolution is located over eastern North America and the North Atlantic; a region that includes most of the SONEX (the SASS (Subsonic Assessment) Ozone and Nitrogen Oxides Experiment) flight paths. The SONEX period (October-November 1997) is simulated by driving the SG-GCTM with assimilated data from the GEOS-STRAT DAS (Goddard Earth Observing System-STRAT Data Assimilation System). A new algorithm is used to parameterize the lightning, flash rates that are needed to calculate emissions of NOy by lightning. Model-calculated upper tropospheric NOy and NOy measurements from the NASA DC-8 aircraft are compared. Spatial variations in NOy were well captured especially with the stretched-grid run; however, model-calculated concentrations were often too high in the upper troposphere, particularly during the first several flights. The lightning algorithm does a reasonably good job; however, the use of emissions from observed lightning, flashes significantly improves the simulation on a few occasions, especially November 3, 1997, indicating that significant uncertainty remains in parameterizing lightning in CTMS. Aircraft emissions play a relatively minor role (about 12%) in the upper tropospheric NOY budget averaged along SONEX flight paths; however, the contribution of such emmissions is as large as about 30% during portions of some flights.

Phonons around a soliton in a continuum model of t-(CH)x

NASA Astrophysics Data System (ADS)

Ono, Y.; Terai, A.; Wada, Y.

1986-05-01

The eigenvalue problem for phonons around a soliton in a continuum model of trans-polyacetylene t-(CH)x, the so-called TLM model (Takayama et al, 1980), is reinvestigated using a kernel which satisfies the correct boundary condition. The three localized modes are reproduced, two with even parity and one with odd parity. The phase-shift analysis of the extended modes confirms their existence if the one-dimensional version of Levinson's theorem is applicable to the present problem. It is found that the phase shifts of even and odd modes differ from each other in the long-wavelength limit. The conclusion of Ito et al. (1984), that the scattering of phonons by the soliton is reflectionless, has to be modified in this limit, where phonons suffer reflection from the soliton.

Conductance signatures of odd-frequency superconductivity in quantum spin Hall systems using a quantum point contact

NASA Astrophysics Data System (ADS)

Fleckenstein, C.; Ziani, N. Traverso; Trauzettel, B.

2018-04-01

Topological superconductors give rise to unconventional superconductivity, which is mainly characterized by the symmetry of the superconducting pairing amplitude. However, since the symmetry of the superconducting pairing amplitude is not directly observable, its experimental identification is rather difficult. In our work, we propose a system, composed of a quantum point contact and proximity-induced s -wave superconductivity at the helical edge of a two-dimensional topological insulator, for which we demonstrate the presence of odd-frequency pairing and its intimate connection to unambiguous transport signatures. Notably, our proposal requires no time-reversal symmetry breaking terms. We discover the domination of crossed Andreev reflection over electron cotunneling in a wide range of parameter space, which is a quite unusual transport regime.

Transition Planning for Culturally and Linguistically Diverse Youth. Brookes Transition to Adulthood Series

ERIC Educational Resources Information Center

Greene, Gary

2011-01-01

Too often, culturally and linguistically diverse (CLD) youth with disabilities have a tougher road to adulthood than their Caucasian peers with disabilities. Reverse the odds with this concise how-to book, the first guide to easing the complex transition process for CLD students with a wide range of special needs. A veteran trainer of transition…

Accuracy of Cup Positioning With the Computed Tomography-Based Two-dimensional to Three-Dimensional Matched Navigation System: A Prospective, Randomized Controlled Study.

PubMed

Yamada, Kazuki; Endo, Hirosuke; Tetsunaga, Tomonori; Miyake, Takamasa; Sanki, Tomoaki; Ozaki, Toshifumi

2018-01-01

The accuracy of various navigation systems used for total hip arthroplasty has been described, but no publications reported the accuracy of cup orientation in computed tomography (CT)-based 2D-3D (two-dimensional to three-dimensional) matched navigation. In a prospective, randomized controlled study, 80 hips including 44 with developmental dysplasia of the hips were divided into a CT-based 2D-3D matched navigation group (2D-3D group) and a paired-point matched navigation group (PPM group). The accuracy of cup orientation (absolute difference between the intraoperative record and the postoperative measurement) was compared between groups. Additionally, multiple logistic regression analysis was performed to evaluate patient factors affecting the accuracy of cup orientation in each navigation. The accuracy of cup inclination was 2.5° ± 2.2° in the 2D-3D group and 4.6° ± 3.3° in the PPM group (P = .0016). The accuracy of cup anteversion was 2.3° ± 1.7° in the 2D-3D group and 4.4° ± 3.3° in the PPM group (P = .0009). In the PPM group, the presence of roof osteophytes decreased the accuracy of cup inclination (odds ratio 8.27, P = .0140) and the absolute value of pelvic tilt had a negative influence on the accuracy of cup anteversion (odds ratio 1.27, P = .0222). In the 2D-3D group, patient factors had no effect on the accuracy of cup orientation. The accuracy of cup positioning in CT-based 2D-3D matched navigation was better than in paired-point matched navigation, and was not affected by patient factors. It is a useful system for even severely deformed pelvises such as developmental dysplasia of the hips. Copyright © 2017 Elsevier Inc. All rights reserved.

Radioimmunotherapy

MedlinePlus

... be involved in RIT. top of page What equipment is used? In addition to equipment needed to ... dimensional images. top of page Who operates the equipment? A radiologist who has specialized training in nuclear ...

Special Issue: NextGen Materials for 3D Printing.

PubMed

Chua, Chee Kai; Yeong, Wai Yee; An, Jia

2018-04-04

Only a handful of materials are well-established in three-dimensional (3D) printing and well-accepted in industrial manufacturing applications. However, recent advances in 3D printable materials have shown potential for enabling numerous novel applications in the future. This special issue, consisting of 2 reviews and 10 research articles, intends to explore the possible materials that could define next-generation 3D printing.

Special Issue: 3D Printing for Biomedical Engineering

PubMed Central

Chua, Chee Kai; Yeong, Wai Yee; An, Jia

2017-01-01

Three-dimensional (3D) printing has a long history of applications in biomedical engineering. The development and expansion of traditional biomedical applications are being advanced and enriched by new printing technologies. New biomedical applications such as bioprinting are highly attractive and trendy. This Special Issue aims to provide readers with a glimpse of the recent profile of 3D printing in biomedical research. PMID:28772604

THE CONCEPT OF PSYCHOTHERAPY IN AYURVEDA WITH SPECIAL REFERENCE TO SATVAVAJAYA

PubMed Central

Murthy, A. R. V.; Singh, R. H.

1987-01-01

Ayurveda conceives in Life (Ayu) as a four dimensional entity i.e. Sarirendriya Satvatma Samyoga. Accordingly it adopts a comprehensive psychosomatic-spiritual approach to preservation of health and cure of diseases. Satvavajaya (psychotherapy) is described as a major non-pharmacological approach to treatment. This paper presents a critical study on the concept of Psychotherapy in Ayurveda with special reference to Satvavajaya. PMID:22557578

On the reduction of 4d $$ \\mathcal{N}=1 $$ theories on $$ {\\mathbb{S}}^2 $$

DOE PAGES

Gadde, Abhijit; Razamat, Shlomo S.; Willett, Brian

2015-11-24

Here, we discuss reductions of generalmore » $$ \\mathcal{N}=1 $$ four dimensional gauge theories on $$ {\\mathbb{S}}^2 $$. The effective two dimensional theory one obtains depends on the details of the coupling of the theory to background fields, which can be translated to a choice of R-symmetry. We argue that, for special choices of R-symmetry, the resulting two dimensional theory has a natural interpretation as an $$ \\mathcal{N}(0,2) $$ gauge theory. As an application of our general observations, we discuss reductions of $$ \\mathcal{N}=1 $$ and $$ \\mathcal{N}=2 $$ dualities and argue that they imply certain two dimensional dualities.« less

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

Meng, Yifei; Zuo, Jian -Min

A diffraction-based technique is developed for the determination of three-dimensional nanostructures. The technique employs high-resolution and low-dose scanning electron nanodiffraction (SEND) to acquire three-dimensional diffraction patterns, with the help of a special sample holder for large-angle rotation. Grains are identified in three-dimensional space based on crystal orientation and on reconstructed dark-field images from the recorded diffraction patterns. Application to a nanocrystalline TiN thin film shows that the three-dimensional morphology of columnar TiN grains of tens of nanometres in diameter can be reconstructed using an algebraic iterative algorithm under specified prior conditions, together with their crystallographic orientations. The principles can bemore » extended to multiphase nanocrystalline materials as well. Furthermore, the tomographic SEND technique provides an effective and adaptive way of determining three-dimensional nanostructures.« less

Functional specializations in human cerebral cortex analyzed using the Visible Man surface-based atlas

NASA Technical Reports Server (NTRS)

Drury, H. A.; Van Essen, D. C.

1997-01-01

We used surface-based representations to analyze functional specializations in the human cerebral cortex. A computerized reconstruction of the cortical surface of the Visible Man digital atlas was generated and transformed to the Talairach coordinate system. This surface was also flattened and used to establish a surface-based coordinate system that respects the topology of the cortical sheet. The linkage between two-dimensional and three-dimensional representations allows the locations of published neuroimaging activation foci to be stereotaxically projected onto the Visible Man cortical flat map. An analysis of two activation studies related to the hearing and reading of music and of words illustrates how this approach permits the systematic estimation of the degree of functional segregation and of potential functional overlap for different aspects of sensory processing.

Detecting Shielded Special Nuclear Materials Using Multi-Dimensional Neutron Source and Detector Geometries

NASA Astrophysics Data System (ADS)

Santarius, John; Navarro, Marcos; Michalak, Matthew; Fancher, Aaron; Kulcinski, Gerald; Bonomo, Richard

2016-10-01

A newly initiated research project will be described that investigates methods for detecting shielded special nuclear materials by combining multi-dimensional neutron sources, forward/adjoint calculations modeling neutron and gamma transport, and sparse data analysis of detector signals. The key tasks for this project are: (1) developing a radiation transport capability for use in optimizing adaptive-geometry, inertial-electrostatic confinement (IEC) neutron source/detector configurations for neutron pulses distributed in space and/or phased in time; (2) creating distributed-geometry, gas-target, IEC fusion neutron sources; (3) applying sparse data and noise reduction algorithms, such as principal component analysis (PCA) and wavelet transform analysis, to enhance detection fidelity; and (4) educating graduate and undergraduate students. Funded by DHS DNDO Project 2015-DN-077-ARI095.

Receipt of Recommended Adolescent Vaccines Among Youth With Special Health Care Needs.

PubMed

McRee, Annie-Laurie; Maslow, Gary R; Reiter, Paul L

2017-05-01

We examined vaccination coverage among youth with special health care needs (YSHCN) using data from parents of adolescents (11-17 years) who responded to a statewide survey in 2010-2012 (n = 2156). Using a validated screening tool, we identified 29% of adolescents as YSHCN. Weighted multivariable logistic regression assessed associations between special health care needs and receipt of tetanus booster, meningococcal, and human papillomavirus (HPV) vaccines. Only 12% of youth had received all 3 vaccines, with greater coverage for individual vaccines (tetanus booster, 91%; meningococcal, 32%; HPV, 26%). YSHCN had greater odds of HPV vaccination than other youth (33% vs 23%, OR = 1.70, 95% CI = 1.16-2.50) but vaccination coverage was similar ( P ≥ .05) for other outcomes. In subgroup analyses, HPV vaccination also differed depending on the number and type of special health care needs identified. Findings highlight low levels of vaccination overall and missed opportunities to administer recommended vaccines among all youth, including YSHCN.

Three-dimensional nanostructure determination from a large diffraction data set recorded using scanning electron nanodiffraction

DOE PAGES

Meng, Yifei; Zuo, Jian -Min

2016-07-04

A diffraction-based technique is developed for the determination of three-dimensional nanostructures. The technique employs high-resolution and low-dose scanning electron nanodiffraction (SEND) to acquire three-dimensional diffraction patterns, with the help of a special sample holder for large-angle rotation. Grains are identified in three-dimensional space based on crystal orientation and on reconstructed dark-field images from the recorded diffraction patterns. Application to a nanocrystalline TiN thin film shows that the three-dimensional morphology of columnar TiN grains of tens of nanometres in diameter can be reconstructed using an algebraic iterative algorithm under specified prior conditions, together with their crystallographic orientations. The principles can bemore » extended to multiphase nanocrystalline materials as well. Furthermore, the tomographic SEND technique provides an effective and adaptive way of determining three-dimensional nanostructures.« less

Teaching Three-Dimensional Structural Chemistry Using Crystal Structure Databases. 2. Teaching Units that Utilize an Interactive Web-Accessible Subset of the Cambridge Structural Database

ERIC Educational Resources Information Center

Battle, Gary M.; Allen, Frank H.; Ferrence, Gregory M.

2010-01-01

A series of online interactive teaching units have been developed that illustrate the use of experimentally measured three-dimensional (3D) structures to teach fundamental chemistry concepts. The units integrate a 500-structure subset of the Cambridge Structural Database specially chosen for their pedagogical value. The units span a number of key…

Analytical solutions of Landau (1+1)-dimensional hydrodynamics

DOE PAGES

Wong, Cheuk-Yin; Sen, Abhisek; Gerhard, Jochen; ...

2014-12-17

To help guide our intuition, summarize important features, and point out essential elements, we review the analytical solutions of Landau (1+1)-dimensional hydrodynamics and exhibit the full evolution of the dynamics from the very beginning to subsequent times. Special emphasis is placed on the matching and the interplay between the Khalatnikov solution and the Riemann simple wave solution at the earliest times and in the edge regions at later times.

Outcomes of elective induction of labour compared with expectant management: population based study

PubMed Central

Ferguson, Evelyn; Duffy, Andrew; Ford, Ian; Chalmers, James; Norman, Jane E

2012-01-01

Objective To determine neonatal outcomes (perinatal mortality and special care unit admission) and maternal outcomes (mode of delivery, delivery complications) of elective induction of labour compared with expectant management. Design Retrospective cohort study using an unselected population database. Setting Consultant and midwife led obstetric units in Scotland 1981-2007. Participants 1 271 549 women with singleton pregnancies of 37 weeks or more gestation. Interventions Outcomes of elective induction of labour (induction of labour with no recognised medical indication) at 37, 38, 39, 40, and 41 weeks’ gestation compared with those of expectant management (continuation of pregnancy to either spontaneous labour, induction of labour or caesarean section at a later gestation). Main outcome measures Extended perinatal mortality, mode of delivery, postpartum haemorrhage, obstetric anal sphincter injury, and admission to a neonatal or special care baby unit. Outcomes were adjusted for age at delivery, parity, year of birth, birth weight, deprivation category, and, where appropriate, mode of delivery. Results At each gestation between 37 and 41 completed weeks, elective induction of labour was associated with a decreased odds of perinatal mortality compared with expectant management (at 40 weeks’ gestation 0.08% (37/44 764) in the induction of labour group versus 0.18% (627/350 643) in the expectant management group; adjusted odds ratio 0.39, 99% confidence interval 0.24 to 0.63), without a reduction in the odds of spontaneous vertex delivery (at 40 weeks’ gestation 79.9% (35 775/44 778) in the induction of labour group versus 73.7% (258 665/350 791) in the expectant management group; adjusted odds ratio 1.26, 1.22 to 1.31). Admission to a neonatal unit was, however, increased in association with elective induction of labour at all gestations before 41 weeks (at 40 weeks’ gestation 8.0% (3605/44 778) in the induction of labour group compared with 7.3% (25 572/350 791) in the expectant management group; adjusted odds ratio 1.14, 1.09 to 1.20). Conclusion Although residual confounding may remain, our findings indicate that elective induction of labour at term gestation can reduce perinatal mortality in developed countries without increasing the risk of operative delivery. PMID:22577197

Entanglement Area Law in Disordered Free Fermion Anderson Model in One, Two, and Three Dimensions

DOE PAGES

Pouranvari, Mohammad; Zhang, Yuhui; Yang, Kun

2015-01-01

We calculate numerically the entanglement entropy of free fermion ground states in one-, two-, and three-dimensional Anderson models and find that it obeys the area law as long as the linear size of the subsystem is sufficiently larger than the mean free path. This result holds in the metallic phase of the three-dimensional Anderson model, where the mean free path is finite although the localization length is infinite. Relation between the present results and earlier ones on area law violation in special one-dimensional models that support metallic phases is discussed.

Mathematical modeling of transformation process of structurally unstable magnetic configurations into structurally stable ones in two-dimensional and three-dimensional geometry

NASA Astrophysics Data System (ADS)

Inovenkov, Igor; Echkina, Eugenia; Ponomarenko, Loubov

Magnetic reconnection is a fundamental process in astrophysical, space and laboratory plasma. In essence, it represents a change of topology of the magnetic field caused by readjustment of the structure of the magnetic field lines. This change leads to release of energy accumulated in the field. We consider transformation process of structurally unstable magnetic configurations into the structurally steady ones from the point of view of the Catastrophe theory. Special attention is paid to modeling of evolution of the structurally unstable three-dimensional magnetic fields.

Viscous Dissipation in One-Dimensional Quantum Liquids

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

Matveev, K. A.; Pustilnik, M.

We develop a theory of viscous dissipation in one-dimensional single-component quantum liquids at low temperatures. Such liquids are characterized by a single viscosity coefficient, the bulk viscosity. We show that for a generic interaction between the constituent particles this viscosity diverges in the zerotemperature limit. In the special case of integrable models, the viscosity is infinite at any temperature, which can be interpreted as a breakdown of the hydrodynamic description. In conclusion, our consideration is applicable to all single-component Galilean- invariant one-dimensional quantum liquids, regardless of the statistics of the constituent particles and the interaction strength.

Entanglement Area Law in Disordered Free Fermion Anderson Model in One, Two, and Three Dimensions

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

Pouranvari, Mohammad; Zhang, Yuhui; Yang, Kun

We calculate numerically the entanglement entropy of free fermion ground states in one-, two-, and three-dimensional Anderson models and find that it obeys the area law as long as the linear size of the subsystem is sufficiently larger than the mean free path. This result holds in the metallic phase of the three-dimensional Anderson model, where the mean free path is finite although the localization length is infinite. Relation between the present results and earlier ones on area law violation in special one-dimensional models that support metallic phases is discussed.

Viscous Dissipation in One-Dimensional Quantum Liquids

DOE PAGES

Matveev, K. A.; Pustilnik, M.

2017-07-20

We develop a theory of viscous dissipation in one-dimensional single-component quantum liquids at low temperatures. Such liquids are characterized by a single viscosity coefficient, the bulk viscosity. We show that for a generic interaction between the constituent particles this viscosity diverges in the zerotemperature limit. In the special case of integrable models, the viscosity is infinite at any temperature, which can be interpreted as a breakdown of the hydrodynamic description. In conclusion, our consideration is applicable to all single-component Galilean- invariant one-dimensional quantum liquids, regardless of the statistics of the constituent particles and the interaction strength.

Twistor Geometry of Null Foliations in Complex Euclidean Space

NASA Astrophysics Data System (ADS)

Taghavi-Chabert, Arman

2017-01-01

We give a detailed account of the geometric correspondence between a smooth complex projective quadric hypersurface Q^n of dimension n ≥ 3, and its twistor space PT, defined to be the space of all linear subspaces of maximal dimension of Q^n. Viewing complex Euclidean space CE^n as a dense open subset of Q^n, we show how local foliations tangent to certain integrable holomorphic totally null distributions of maximal rank on CE^n can be constructed in terms of complex submanifolds of PT. The construction is illustrated by means of two examples, one involving conformal Killing spinors, the other, conformal Killing-Yano 2-forms. We focus on the odd-dimensional case, and we treat the even-dimensional case only tangentially for comparison.

Nonalgebraic integrability of one reversible dynamical system of the Cremona type

NASA Astrophysics Data System (ADS)

Rerikh, K. V.

1998-05-01

A reversible dynamical system (RDS) and a system of nonlinear functional equations, defined by a certain rational quadratic Cremona mapping and arising from the static model of the dispersion approach in the theory of strong interactions [the Chew-Low-type equations with crossing-symmetry matrix A(l,1)], are considered. This RDS is split into one- and two-dimensional ones. An explicit Cremona transformation that completely determines the exact solution of the two-dimensional system is found. This solution depends on an odd function satisfying a nonlinear autonomous three-point functional equation. Nonalgebraic integrability of RDS under consideration is proved using the method of Poincaré normal forms and the Siegel theorem on biholomorphic linearization of a mapping at a nonresonant fixed point.

Three-Dimensional Models of Topological Insulators: Engineering of Dirac Cones and Robustness of the Spin Texture

NASA Astrophysics Data System (ADS)

Soriano, David; Ortmann, Frank; Roche, Stephan

2012-12-01

We design three-dimensional models of topological insulator thin films, showing a tunability of the odd number of Dirac cones driven by the atomic-scale geometry at the boundaries. A single Dirac cone at the Γ-point can be obtained as well as full suppression of quantum tunneling between Dirac states at geometrically differentiated surfaces. The spin texture of surface states changes from a spin-momentum-locking symmetry to a surface spin randomization upon the introduction of bulk disorder. These findings illustrate the richness of the Dirac physics emerging in thin films of topological insulators and may prove utile for engineering Dirac cones and for quantifying bulk disorder in materials with ultraclean surfaces.

Two-dimensional topological insulators with large bulk energy gap

NASA Astrophysics Data System (ADS)

Yang, Z. Q.; Jia, Jin-Feng; Qian, Dong

2016-11-01

Two-dimensional (2D) topological insulators (TIs, or quantum spin Hall insulators) are special insulators that possess bulk 2D electronic energy gap and time-reversal symmetry protected one-dimensional (1D) edge state. Carriers in the edge state have the property of spin-momentum locking, enabling dissipation-free conduction along the 1D edge. The existence of 2D TIs was confirmed by experiments in semiconductor quantum wells. However, the 2D bulk gaps in those quantum wells are extremely small, greatly limiting potential application in future electronics and spintronics. Despite this limitation, 2D TIs with a large bulk gap attracted plenty of interest. In this paper, recent progress in searching for TIs with a large bulk gap is reviewed briefly. We start by introducing some theoretical predictions of these new materials and then discuss some recent important achievements in crystal growth and characterization. Project supported by the National Natural Science Foundation of China (Grant Nos. U1632272, 11574201, and 11521404). D. Q. acknowledges support from the Changjiang Scholars Program, China and the Program for Professor of Special Appointment (Eastern Scholar), China.

Intersection of three-dimensional geometric surfaces

NASA Technical Reports Server (NTRS)

Crisp, V. K.; Rehder, J. J.; Schwing, J. L.

1985-01-01

Calculating the line of intersection between two three-dimensional objects and using the information to generate a third object is a key element in a geometry development system. Techniques are presented for the generation of three-dimensional objects, the calculation of a line of intersection between two objects, and the construction of a resultant third object. The objects are closed surfaces consisting of adjacent bicubic parametric patches using Bezier basis functions. The intersection determination involves subdividing the patches that make up the objects until they are approximately planar and then calculating the intersection between planes. The resulting straight-line segments are connected to form the curve of intersection. The polygons in the neighborhood of the intersection are reconstructed and put back into the Bezier representation. A third object can be generated using various combinations of the original two. Several examples are presented. Special cases and problems were encountered, and the method for handling them is discussed. The special cases and problems included intersection of patch edges, gaps between adjacent patches because of unequal subdivision, holes, or islands within patches, and computer round-off error.

Constipation in specialized palliative care: factors related to constipation when applying different definitions.

PubMed

Erichsén, E; Milberg, A; Jaarsma, T; Friedrichsen, M

2016-02-01

For patients in palliative care, constipation is primarily a result of opioid treatment. Impacts from other factors related to constipation in palliative care are rarely studied. The aim was to identify factors related to constipation in patients in palliative care, and then to compare these factors between patients with different types of constipation and patients without constipation. Cross-sectional data on constipation was collected with a 26-item questionnaire from 485 patients in 38 specialist palliative care units in Sweden. Three different constipation groups were used; MC ONLY, PC ONLY, and MC & PC. Logistic regression analyses were used to calculate odds ratios. Patients with <3 defecations/week, MC ONLY, (n = 36) had higher odds of being hospitalized, bed-restricted, in need of personal assistance for toilet visits, and of having a poor fluid intake. Patients with the perception of being constipated, PC ONLY, (n = 93) had higher odds of having poor appetite, hemorrhoids, hard stool, more opioid treatment, less laxative treatment and of being more dissatisfied with constipation information. Patients with both <3 defecations/week and a perception of being constipated, MC & PC, (n = 78) had higher odds of having cancer- disease. There were several significant factors related to constipation with higher odds than opioid- treatment, for patients in palliative care, such as; hard stool, cancer diagnosis, dissatisfaction with information, low fluid intake, hemorrhoids, bed restriction, hospitalization, and need of personal assistance for toilet visits.

Special Issue: NextGen Materials for 3D Printing

PubMed Central

Yeong, Wai Yee

2018-01-01

Only a handful of materials are well-established in three-dimensional (3D) printing and well-accepted in industrial manufacturing applications. However, recent advances in 3D printable materials have shown potential for enabling numerous novel applications in the future. This special issue, consisting of 2 reviews and 10 research articles, intends to explore the possible materials that could define next-generation 3D printing. PMID:29617311

u-Constacyclic codes over F_p+u{F}_p and their applications of constructing new non-binary quantum codes

NASA Astrophysics Data System (ADS)

Gao, Jian; Wang, Yongkang

2018-01-01

Structural properties of u-constacyclic codes over the ring F_p+u{F}_p are given, where p is an odd prime and u^2=1. Under a special Gray map from F_p+u{F}_p to F_p^2, some new non-binary quantum codes are obtained by this class of constacyclic codes.

Evaluating the morphological completeness of a training image.

PubMed

Gao, Mingliang; Teng, Qizhi; He, Xiaohai; Feng, Junxi; Han, Xue

2017-05-01

Understanding the three-dimensional (3D) stochastic structure of a porous medium is helpful for studying its physical properties. A 3D stochastic structure can be reconstructed from a two-dimensional (2D) training image (TI) using mathematical modeling. In order to predict what specific morphology belonging to a TI can be reconstructed at the 3D orthogonal slices by the method of 3D reconstruction, this paper begins by introducing the concept of orthogonal chords. After analyzing the relationship among TI morphology, orthogonal chords, and the 3D morphology of orthogonal slices, a theory for evaluating the morphological completeness of a TI is proposed for the cases of three orthogonal slices and of two orthogonal slices. The proposed theory is evaluated using four TIs of porous media that represent typical but distinct morphological types. The significance of this theoretical evaluation lies in two aspects: It allows special morphologies, for which the attributes of a TI can be reconstructed at a special orthogonal slice of a 3D structure, to be located and quantified, and it can guide the selection of an appropriate reconstruction method for a special TI.

Prevalence and Risk Factors for Depressive Reaction among Resident Survivors after the Tsunami following the Great East Japan Earthquake, March 11, 2011

PubMed Central

Matsubara, Chieko; Murakami, Hitoshi; Imai, Koubun; Mizoue, Tetsuya; Akashi, Hidechika; Miyoshi, Chiaki; Nakasa, Tamotsu

2014-01-01

Objectives The Great East Japan Earthquake caused a gigantic tsunami which devastated coastal areas of northern Japan on 11 March 2011. Despite the large number of ‘resident survivors’ who continued to reside in their damaged houses on the second or upper floors, research on the mental health of these individuals has been limited. This study explored the prevalence of depressive reaction and risk factors for depressive reaction among these resident survivors. Methods A cross-sectional household health support needs screening was conducted for resident survivors in Higashi-Matsushima city, Miyagi prefecture, two to four months after the tsunami. The health interview that was conducted including mental status, assessed by the Patient Health Questionnaire-2 (PHQ-2). Results Of 5,454 respondents, 8.1% had depressive reaction. After adjustment by the number of weeks from the tsunami and the mortality rate at each respondent's place of residence, depressive reaction was significantly associated with house flooding below or above the ground floor (odds ratios of 1.92, 2.36, respectively), the unavailability of gas supply (odds ratio, 1.67), being female (odds ratio, 1.47), middle aged or elderly (odds ratios of 2.41, 2.42, respectively), regular intake of psychotropic medicine(s) since before the tsunami (odds ratio, 2.53) and the presence of one to five or more than six cohabiters (odds ratios of 0.61, 0.52, respectively). Conclusions The results suggest a considerable psychological burden (depressive reaction) following the tsunami among resident survivors. Special supports for families with psychiatric problems need to be considered among resident survivors. Restoration of lifeline utilities and the strengthening of social ties of persons living alone may help prevent depressive reaction among resident survivors after a tsunami. PMID:25279563

Prevalence and risk factors for depressive reaction among resident survivors after the tsunami following the Great East Japan Earthquake, March 11, 2011.

PubMed

Matsubara, Chieko; Murakami, Hitoshi; Imai, Koubun; Mizoue, Tetsuya; Akashi, Hidechika; Miyoshi, Chiaki; Nakasa, Tamotsu

2014-01-01

The Great East Japan Earthquake caused a gigantic tsunami which devastated coastal areas of northern Japan on 11 March 2011. Despite the large number of 'resident survivors' who continued to reside in their damaged houses on the second or upper floors, research on the mental health of these individuals has been limited. This study explored the prevalence of depressive reaction and risk factors for depressive reaction among these resident survivors. A cross-sectional household health support needs screening was conducted for resident survivors in Higashi-Matsushima city, Miyagi prefecture, two to four months after the tsunami. The health interview that was conducted including mental status, assessed by the Patient Health Questionnaire-2 (PHQ-2). Of 5,454 respondents, 8.1% had depressive reaction. After adjustment by the number of weeks from the tsunami and the mortality rate at each respondent's place of residence, depressive reaction was significantly associated with house flooding below or above the ground floor (odds ratios of 1.92, 2.36, respectively), the unavailability of gas supply (odds ratio, 1.67), being female (odds ratio, 1.47), middle aged or elderly (odds ratios of 2.41, 2.42, respectively), regular intake of psychotropic medicine(s) since before the tsunami (odds ratio, 2.53) and the presence of one to five or more than six cohabiters (odds ratios of 0.61, 0.52, respectively). The results suggest a considerable psychological burden (depressive reaction) following the tsunami among resident survivors. Special supports for families with psychiatric problems need to be considered among resident survivors. Restoration of lifeline utilities and the strengthening of social ties of persons living alone may help prevent depressive reaction among resident survivors after a tsunami.

Atrioventricular depolarization differences identify coronary artery anomalies in Kawasaki disease.

PubMed

Cortez, Daniel; Sharma, Nandita; Jone, Pei-Ni

2017-03-01

Kawasaki disease (KD) is the leading cause of acquired heart disease in children. Signal average electrocardiogram changes in patients during the acute phase of KD with coronary artery anomalies (CAA) include depolarization changes. We set out to determine if 12-lead-derived atrioventricular depolarization differences can identify CAA in patients with KD. A blinded, retrospective case-control study of patients with KD was performed. Deep Q waves, corrected QT-intervals (QTc), spatial QRS-T angles, T-wave vector magnitudes (RMS-T), and a novel parameter for assessment of atrioventricular depolarization difference (the spatial PR angle) and a two dimensional PR angle were assessed. Comparisons between groups were performed to test for significant differences. One hundred one patients with KD were evaluated, with 68 having CAA (67.3%, mean age 3.6 ± 3.0 years, 82.6% male), and 32 without CAA (31.7%, mean age 2.7 ± 3.2 years, 70.4% male). The spatial PR angle significantly discriminated KD patients with CAA from those without, 59.7° ± 31.1° versus 41.6° ± 11.5° (p < .001). A spatial PR angle cutoff value of 56.9° gave positive/negative predictive values and odds ratios of 93.8%, 43.5%, and 11.5% (95% confidence interval (CI) 2.6-52.2). The two dimensional PR angle either below 7° or above 92° gave positive/negative predictive values and odds ratios of 100.0%, 38.8%, and 21.1% (95% CI 1.2-362.8). No other parameters significantly differentiated the groups. Atrioventricular depolarization differences, measured by the spatial or two dimensional PR angle differentiate KD patients with CAA versus those without. © 2016 Wiley Periodicals, Inc.

Local density of states in two-dimensional topological superconductors under a magnetic field: Signature of an exterior Majorana bound state

NASA Astrophysics Data System (ADS)

Suzuki, Shu-Ichiro; Kawaguchi, Yuki; Tanaka, Yukio

2018-04-01

We study quasiparticle states on a surface of a topological insulator (TI) with proximity-induced superconductivity under an external magnetic field. An applied magnetic field creates two Majorana bound states: a vortex Majorana state localized inside a vortex core and an exterior Majorana state localized along a circle centered at the vortex core. We calculate the spin-resolved local density of states (LDOS) and demonstrate that the shrinking of the radius of the exterior Majorana state, predicted in R. S. Akzyanov et al., Phys. Rev. B 94, 125428 (2016), 10.1103/PhysRevB.94.125428, under a strong magnetic field can be seen in LDOS without smeared out by nonzero-energy states. The spin-resolved LDOS further reveals that the spin of the exterior Majorana state is strongly spin-polarized. Accordingly, the induced odd-frequency spin-triplet pairs are found to be spin-polarized as well. In order to detect the exterior Majorana states, however, the Fermi energy should be closed to the Dirac point to avoid contributions from continuum levels. We also study a different two-dimensional topological-superconducting system where a two-dimensional electron gas with the spin-orbit coupling is sandwiched between an s -wave superconductor and a ferromagnetic insulator. We show that the radius of an exterior Majorana state can be tuned by an applied magnetic field. However, on the contrary to the results at a TI surface, neither the exterior Majorana state nor the induced odd-frequency spin-triplet pairs are spin-polarized. We conclude that the spin polarization of the Majorana state is attributed to the spin-polarized Landau level, which is characteristic for systems with the Dirac-like dispersion.

Disruptive Mood Dysregulation Disorder in a Community Mental Health Clinic: Prevalence, Comorbidity and Correlates.

PubMed

Freeman, Andrew J; Youngstrom, Eric A; Youngstrom, Jennifer K; Findling, Robert L

2016-03-01

The revision of the Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-5) added a new diagnosis of disruptive mood dysregulation disorder (DMDD) to depressive disorders. This study examines the prevalence, comorbidity, and correlates of the new disorder, with a particular focus on its overlap with oppositional defiant disorder (ODD), with which DMDD shares core symptoms. Data were obtained from 597 youth 6-18 years of age who participated in a systematic assessment of symptoms offered to all intakes at a community mental health center (sample accrued from July 2003 to March 2008). Assessment included diagnostic, symptomatic, and functional measures. DMDD was diagnosed using a post-hoc definition from item-level ratings on the Schedule for Affective Disorders and Schizophrenia for School-Age Children that closely matches the DSM-5 definition. Caregivers rated youth on the Child Behavior Checklist. Approximately 31% of youth met the operational definition of DMDD, and 40% had Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) diagnoses of ODD. Youth with DMDD almost always had ODD (odds ratio [OR] = 53.84) and displayed higher rates of comorbidity with attention-deficit/hyperactivity disorder (ADHD) and conduct disorder than youth without DMDD. Caregivers of youth with DMDD reported more symptoms of aggressive behavior, rule-breaking, social problems, anxiety/depression, attention problems, and thought problems than all other youth without DMDD. Compared with youth with ODD, youth with DMDD were not significantly different in terms of categorical or dimensional approaches to comorbidity and impairment. The new diagnosis of DMDD might be common in community mental health clinics. Youth with DMDD displayed more severe symptoms and poorer functioning than youth without DMDD. However, DMDD almost entirely overlaps with ODD and youth with DMDD were not significantly different than youth with ODD. These findings raise concerns about the potentially confusing effects of using DMDD in clinical settings, particularly given that DSM-5 groups DMDD with depressive disorders, but ODD remains a disruptive behavior disorder, potentially changing the decision-making framework that clinicians use to select treatments.

A collection of edge-based elements

NASA Technical Reports Server (NTRS)

Kempel, Leo C.; Volakis, John L.

1992-01-01

Edge-based elements have proved useful in solving electromagnetic problems since they are nondivergent. Previous authors have presented several two and three dimensional elements. Herein, we present four types of elements which are suitable for modeling several types of three dimensional geometries. Distorted brick and triangular prism elements are given in cartesian coordinates as well as the specialized cylindrical shell and pie-shaped prism elements which are suitable for problems best described in polar cylindrical coordinates.

Software applications to three-dimensional visualization of forest landscapes -- A case study demontrating the use of visual nature studio (VNS) in visualizing fire spread in forest landscapes

Treesearch

Brian J. Williams; Bo Song; Chou Chiao-Ying; Thomas M. Williams; John Hom

2010-01-01

Three-dimensional (3D) visualization is a useful tool that depicts virtual forest landscapes on computer. Previous studies in visualization have required high end computer hardware and specialized technical skills. A virtual forest landscape can be used to show different effects of disturbances and management scenarios on a computer, which allows observation of forest...

Two Legendre-Dual-Petrov-Galerkin Algorithms for Solving the Integrated Forms of High Odd-Order Boundary Value Problems

PubMed Central

Abd-Elhameed, Waleed M.; Doha, Eid H.; Bassuony, Mahmoud A.

2014-01-01

Two numerical algorithms based on dual-Petrov-Galerkin method are developed for solving the integrated forms of high odd-order boundary value problems (BVPs) governed by homogeneous and nonhomogeneous boundary conditions. Two different choices of trial functions and test functions which satisfy the underlying boundary conditions of the differential equations and the dual boundary conditions are used for this purpose. These choices lead to linear systems with specially structured matrices that can be efficiently inverted, hence greatly reducing the cost. The various matrix systems resulting from these discretizations are carefully investigated, especially their complexities and their condition numbers. Numerical results are given to illustrate the efficiency of the proposed algorithms, and some comparisons with some other methods are made. PMID:24616620

Thermal equilibrium and statistical thermometers in special relativity.

PubMed

Cubero, David; Casado-Pascual, Jesús; Dunkel, Jörn; Talkner, Peter; Hänggi, Peter

2007-10-26

There is an intense debate in the recent literature about the correct generalization of Maxwell's velocity distribution in special relativity. The most frequently discussed candidate distributions include the Jüttner function as well as modifications thereof. Here we report results from fully relativistic one-dimensional molecular dynamics simulations that resolve the ambiguity. The numerical evidence unequivocally favors the Jüttner distribution. Moreover, our simulations illustrate that the concept of "thermal equilibrium" extends naturally to special relativity only if a many-particle system is spatially confined. They make evident that "temperature" can be statistically defined and measured in an observer frame independent way.

Electromagnetic inverse scattering

NASA Technical Reports Server (NTRS)

Bojarski, N. N.

1972-01-01

A three-dimensional electromagnetic inverse scattering identity, based on the physical optics approximation, is developed for the monostatic scattered far field cross section of perfect conductors. Uniqueness of this inverse identity is proven. This identity requires complete scattering information for all frequencies and aspect angles. A nonsingular integral equation is developed for the arbitrary case of incomplete frequence and/or aspect angle scattering information. A general closed-form solution to this integral equation is developed, which yields the shape of the scatterer from such incomplete information. A specific practical radar solution is presented. The resolution of this solution is developed, yielding short-pulse target resolution radar system parameter equations. The special cases of two- and one-dimensional inverse scattering and the special case of a priori knowledge of scatterer symmetry are treated in some detail. The merits of this solution over the conventional radar imaging technique are discussed.

A vector scanning processing technique for pulsed laser velocimetry

NASA Technical Reports Server (NTRS)

Wernet, Mark P.; Edwards, Robert V.

1989-01-01

Pulsed-laser-sheet velocimetry yields two-dimensional velocity vectors across an extended planar region of a flow. Current processing techniques offer high-precision (1-percent) velocity estimates, but can require hours of processing time on specialized array processors. Sometimes, however, a less accurate (about 5 percent) data-reduction technique which also gives unambiguous velocity vector information is acceptable. Here, a direct space-domain processing technique is described and shown to be far superior to previous methods in achieving these objectives. It uses a novel data coding and reduction technique and has no 180-deg directional ambiguity. A complex convection vortex flow was recorded and completely processed in under 2 min on an 80386-based PC, producing a two-dimensional velocity-vector map of the flowfield. Pulsed-laser velocimetry data can thus be reduced quickly and reasonably accurately, without specialized array processing hardware.

Order and chaos in the one-dimensional ϕ4 model: N-dependence and the Second Law of Thermodynamics

NASA Astrophysics Data System (ADS)

Hoover, William Graham; Aoki, Kenichiro

2017-08-01

We revisit the equilibrium one-dimensional ϕ4 model from the dynamical systems point of view. We find an infinite number of periodic orbits which are computationally stable. At the same time some of the orbits are found to exhibit positive Lyapunov exponents! The periodic orbits confine every particle in a periodic chain to trace out either the same or a mirror-image trajectory in its two-dimensional phase space. These ;computationally stable; sets of pairs of single-particle orbits are either symmetric or antisymmetric to the very last computational bit. In such a periodic chain the odd-numbered and even-numbered particles' coordinates and momenta are either identical or differ only in sign. ;Positive Lyapunov exponents; can and do result if an infinitesimal perturbation breaking a perfect two-dimensional antisymmetry is introduced so that the motion expands into a four-dimensional phase space. In that extended space a positive exponent results. We formulate a standard initial condition for the investigation of the microcanonical chaotic number dependence of the model. We speculate on the uniqueness of the model's chaotic sea and on the connection of such collections of deterministic and time-reversible states to the Second Law of Thermodynamics.

Configuration and Spin Assignments of Yrast Band for Doubly Odd Nucleus 122Cs

NASA Astrophysics Data System (ADS)

Pu, Yun-wei; Wen, Jia-yan; Zhu, Shun-quan; Zheng, Ren-rong

1998-07-01

Energy spectrum of yrast band for 122Cs is studied by using particle-rotor model (PRM) of odd-odd nuclei, in which special attention is paid to the model basis accounting for the effect of the instability γ vibration perturbation around axial symmetry. In order to check the assignments of this band, two calculation schemes are put into practice. The first one is for previous πh11/2 otimes νg7/2 configuration with bandhead spin I0 = (6-) which was obtained from cranked shell model (CSM) calculation, and the other one is for πh11/2 otimes νh11/2 configuration with I0 = (9+) supported by the systematic analyses of experimental data. A qualitative comparison between the present PRM calculation and that of CSM has also been made. The results indicate that, rather than πh11/2 otimes νg7/2 with I0 = (6-), πh11/2 otimes νh11/2 with I0 = (9+) is a more reasonable assignment to the yrast band in 122Cs.

[Medical speciality, belief in Santa and the risk of divorce].

PubMed

Lund, Kamma Sundgaard; Aabenhus, Rune Munck; Arreskov, Anne Beiter

2016-12-12

Christmas is a unique time for family occasions - unfortunately the number of divorces increase in the months after Christmas. In this study, we examined the relationship between medical speciality, length of relationship, risk of divorce and if belief in Santa impacted on these outcomes. A questionnaire was developed from the lived experiences of the authors and distributed to doctors of any speciality through links (SurveyXact) in emails, text messages and Facebook from June 28 2016 to August 1 2016. Multivariate regression models were used to analyze the results. A total of 1,100 completed questionnaires were included in the analyses. The divorce rate among respondents was 12%. Compared to the speciality "general practice" all other specialities had higher divorce rates. The highest risk of divorce was reported by physicians specialized in psychiatry (odds ratio 2.13 (95% confidence interval: 1.03-4.43)). Belief in Santa was associated with a slightly increased risk of divorce in all medical specialities, with the exception of psychiatry. General practitioners also exhibited the longest duration of relationships compared to peers in other medical specialities. Being a general practitioner was associated with a low risk of divorce and significantly longer relationships than in other medical specialities. Belief in Santa in regard to divorce only seemed to be beneficial for psychiatrists. So please participate in the joy of Christmas but do not rely on Santa - go shop your own presents for the family. none. not relevant.

Observation of the quantum Hall effect in δ-doped SrTiO3

PubMed Central

Matsubara, Y.; Takahashi, K. S.; Bahramy, M. S.; Kozuka, Y.; Maryenko, D.; Falson, J.; Tsukazaki, A.; Tokura, Y.; Kawasaki, M.

2016-01-01

The quantum Hall effect is a macroscopic quantum phenomenon in a two-dimensional electron system. The two-dimensional electron system in SrTiO3 has sparked a great deal of interest, mainly because of the strong electron correlation effects expected from the 3d orbitals. Here we report the observation of the quantum Hall effect in a dilute La-doped SrTiO3-two-dimensional electron system, fabricated by metal organic molecular-beam epitaxy. The quantized Hall plateaus are found to be solely stemming from the low Landau levels with even integer-filling factors, ν=4 and 6 without any contribution from odd ν's. For ν=4, the corresponding plateau disappears on decreasing the carrier density. Such peculiar behaviours are proposed to be due to the crossing between the Landau levels originating from the two subbands composed of d orbitals with different effective masses. Our findings pave a way to explore unprecedented quantum phenomena in d-electron systems. PMID:27228903

Study of multi-dimensional radiative energy transfer in molecular gases

NASA Technical Reports Server (NTRS)

Liu, Jiwen; Tiwari, S. N.

1993-01-01

The Monte Carlo method (MCM) is applied to analyze radiative heat transfer in nongray gases. The nongray model employed is based on the statistical arrow band model with an exponential-tailed inverse intensity distribution. Consideration of spectral correlation results in some distinguishing features of the Monte Carlo formulations. Validation of the Monte Carlo formulations has been conducted by comparing results of this method with other solutions. Extension of a one-dimensional problem to a multi-dimensional problem requires some special treatments in the Monte Carlo analysis. Use of different assumptions results in different sets of Monte Carlo formulations. The nongray narrow band formulations provide the most accurate results.

A development of two-dimensional birefringence distribution measurement system with a sampling rate of 1.3 MHz

NASA Astrophysics Data System (ADS)

Onuma, Takashi; Otani, Yukitoshi

2014-03-01

A two-dimensional birefringence distribution measurement system with a sampling rate of 1.3 MHz is proposed. A polarization image sensor is developed as core device of the system. It is composed of a pixelated polarizer array made from photonic crystal and a parallel read out circuit with a multi-channel analog to digital converter specialized for two-dimensional polarization detection. By applying phase shifting algorism with circularly-polarized incident light, birefringence phase difference and azimuthal angle can be measured. The performance of the system is demonstrated experimentally by measuring actual birefringence distribution and polarization device such as Babinet-Soleil compensator.

Cardiovascular Imaging and Image Processing: Theory and Practice - 1975

NASA Technical Reports Server (NTRS)

Harrison, Donald C. (Editor); Sandler, Harold (Editor); Miller, Harry A. (Editor); Hood, Manley J. (Editor); Purser, Paul E. (Editor); Schmidt, Gene (Editor)

1975-01-01

Ultrasonography was examined in regard to the developmental highlights and present applicatons of cardiac ultrasound. Doppler ultrasonic techniques and the technology of miniature acoustic element arrays were reported. X-ray angiography was discussed with special considerations on quantitative three dimensional dynamic imaging of structure and function of the cardiopulmonary and circulatory systems in all regions of the body. Nuclear cardiography and scintigraphy, three--dimensional imaging of the myocardium with isotopes, and the commercialization of the echocardioscope were studied.

Three-Dimensional Printing as an Interdisciplinary Communication Tool: Preparing for Removal of a Giant Renal Tumor and Atrium Neoplastic Mass.

PubMed

Golab, Adam; Slojewski, Marcin; Brykczynski, Miroslaw; Lukowiak, Magdalena; Boehlke, Marek; Matias, Daniel; Smektala, Tomasz

2016-08-22

Three-dimensional (3D) printing involves preparing 3D objects from a digital model. These models can be used to plan and practice surgery. We used 3D printing to plan for a rare complicated surgery involving the removal of a renal tumor and neoplastic mass, which reached the heart atrium. A printed kidney model was an essential element of communication for physicians with different specializations.

Preparing to Predict: The Second Autonomous Ocean Sampling Network (AOSN-II) Experiment in the Monterey Bay

DTIC Science & Technology

2008-06-06

MBARI buoy M2, profiling to 250 m depth (Figure 1). Instruments on board included a CTD, fluorometer, oxygen and nitrate sensors, bioluminescence, and...dimensional multiscale ocean variability: Massachusetts Bay. Journal of Marine Systems, Special issue on “Three-dimensional ocean circulation: Lagrangian...Oceanography”, T. Paluszkiewicz and S. Harper, Eds., Vol. 19, 1, 172-183. Liang, X.S. and Anderson, D.G.M. (2007) Multiscale Window Transform, SIAM J

Birman—Wenzl—Murakami Algebra and Topological Basis

NASA Astrophysics Data System (ADS)

Zhou, Cheng-Cheng; Xue, Kang; Wang, Gang-Cheng; Sun, Chun-Fang; Du, Gui-Jiao

2012-02-01

In this paper, we use entangled states to construct 9 × 9-matrix representations of Temperley—Lieb algebra (TLA), then a family of 9 × 9-matrix representations of Birman—Wenzl—Murakami algebra (BWMA) have been presented. Based on which, three topological basis states have been found. And we apply topological basis states to recast nine-dimensional BWMA into its three-dimensional counterpart. Finally, we find the topological basis states are spin singlet states in special case.

Propagation of relativistic surface harmonics radiation in free space

NASA Astrophysics Data System (ADS)

an der Brügge, Daniel; Pukhov, Alexander

2007-09-01

Relativistic high-harmonics generation from overdense plasma surfaces is studied using three-dimensional particle-in-cell simulations. It is shown that the simple vacuum propagation in the real three-dimensional geometry strongly affects the harmonics spectrum on the optical axis. It may even lead to the formation of attosecond pulses without any special optical filters. To make good use of these effects it is necessary to shape either the laser pulse focal spot, or the surface material in such a way that the S-number of the interaction [see Gordienko and Pukhov, Phys. Plasmas 12, 043109 (2005)] is preserved over the largest possible area. The three-dimensional simulations are carefully compared with the one-dimensional ones. It is shown that the one-dimensional models work well even in cases where the laser is focused to a quite small spot on the harmonics generating surface (σ≈λ).

Coherent backscattering enhancement in cavities. Highlights of the role of symmetry.

PubMed

Gallot, Thomas; Catheline, Stefan; Roux, Philippe

2011-04-01

Through experiments and simulations, the consequences of symmetry on coherent backscattering enhancement (CBE) are studied in cavities. Three main results are highlighted. First, the CBE outside the source is observed: (a) on a single symmetric point in a one-dimensional (1-D) cavity, in a disk and in a symmetric chaotic plate; (b) on three symmetric points in a two-dimensional (2-D) rectangle; and (c) on seven symmetric points in a three-dimensional (3-D) parallelepiped cavity. Second, the existence of enhanced intensity lines and planes in 2-D and 3-D simple-shape cavities is demonstrated. Third, it is shown how the anti-symmetry caused by the special boundary conditions is responsible for the existence of a coherent backscattering decrement with a dimensional dependence of R = (½)(d), with d = 1,2,3 as the dimensionality of the cavity.

Three-dimensional organization of dermal fibroblasts by macromass culture.

PubMed

Deshpande, Manisha

2008-01-01

The three-dimensional organization of cells by high-cell-seeding-density culture, termed 'macromass culture', is described. By macromass culture, dermal fibroblasts can be made to organize themselves into a unified three-dimensional form without the aid of a scaffold, and macroscopic constructs, named macromasses, can be made wholly from cells. The sole factor causing three-dimensional organization is culture of cells at high cell seeding density per unit area. No scaffold or extraneous matrix is used for the generation of macromasses; they are of completely cellular origin. No other agents or external influences such as tissue-inducing chemicals, tissue-inducing growth factors, substratum with special properties, rotational culture, centrifugation etc. are employed for macromass formation, and all seeded cells become part of the cohesive construct. These three-dimensional constructs have the potential for use as in vitro tissue analogues, and a possible application for in vitro cytotoxicity testing is demonstrated.

Fragile surface zero-energy flat bands in three-dimensional chiral superconductors

NASA Astrophysics Data System (ADS)

Kobayashi, Shingo; Tanaka, Yukio; Sato, Masatoshi

2015-12-01

We study surface zero-energy flat bands in three-dimensional chiral superconductors with pz(px+i py) ν -wave pairing symmetry (ν is a nonzero integer), based on topological arguments and tunneling conductance. It is shown that the surface flat bands are fragile against (i) the surface misorientation and (ii) the surface Rashba spin-orbit interaction. The fragility of (i) is specific to chiral SCs, whereas that of (ii) happens for general odd-parity SCs. We demonstrate that these flat-band instabilities vanish or suppress a zero-bias conductance peak in a normal/insulator/superconductor junction, which behavior is clearly different from high-Tc cuprates and noncentrosymmetric superconductors. By calculating the angle-resolved conductance, we also discuss a topological surface state associated with the coexistence of line and point nodes.

Odd-Parity Superconductivity near an Inversion Breaking Quantum Critical Point in One Dimension

DOE PAGES

Ruhman, Jonathan; Kozii, Vladyslav; Fu, Liang

2017-05-31

In this work, we study how an inversion-breaking quantum critical point affects the ground state of a one-dimensional electronic liquid with repulsive interaction and spin-orbit coupling. We find that regardless of the interaction strength, the critical fluctuations always lead to a gap in the electronic spin sector. The origin of the gap is a two-particle backscattering process, which becomes relevant due to renormalization of the Luttinger parameter near the critical point. The resulting spin-gapped state is topological and can be considered as a one-dimensional version of a spin-triplet superconductor. Interestingly, in the case of a ferromagnetic critical point, the Luttingermore » parameter is renormalized in the opposite manner, such that the system remains nonsuperconducting.« less

Long-Time Numerical Integration of the Three-Dimensional Wave Equation in the Vicinity of a Moving Source

NASA Technical Reports Server (NTRS)

Ryabenkii, V. S.; Turchaninov, V. I.; Tsynkov, S. V.

1999-01-01

We propose a family of algorithms for solving numerically a Cauchy problem for the three-dimensional wave equation. The sources that drive the equation (i.e., the right-hand side) are compactly supported in space for any given time; they, however, may actually move in space with a subsonic speed. The solution is calculated inside a finite domain (e.g., sphere) that also moves with a subsonic speed and always contains the support of the right-hand side. The algorithms employ a standard consistent and stable explicit finite-difference scheme for the wave equation. They allow one to calculate tile solution for arbitrarily long time intervals without error accumulation and with the fixed non-growing amount of tile CPU time and memory required for advancing one time step. The algorithms are inherently three-dimensional; they rely on the presence of lacunae in the solutions of the wave equation in oddly dimensional spaces. The methodology presented in the paper is, in fact, a building block for constructing the nonlocal highly accurate unsteady artificial boundary conditions to be used for the numerical simulation of waves propagating with finite speed over unbounded domains.

Online 3D Ear Recognition by Combining Global and Local Features.

PubMed

Liu, Yahui; Zhang, Bob; Lu, Guangming; Zhang, David

2016-01-01

The three-dimensional shape of the ear has been proven to be a stable candidate for biometric authentication because of its desirable properties such as universality, uniqueness, and permanence. In this paper, a special laser scanner designed for online three-dimensional ear acquisition was described. Based on the dataset collected by our scanner, two novel feature classes were defined from a three-dimensional ear image: the global feature class (empty centers and angles) and local feature class (points, lines, and areas). These features are extracted and combined in an optimal way for three-dimensional ear recognition. Using a large dataset consisting of 2,000 samples, the experimental results illustrate the effectiveness of fusing global and local features, obtaining an equal error rate of 2.2%.

Online 3D Ear Recognition by Combining Global and Local Features

PubMed Central

Liu, Yahui; Zhang, Bob; Lu, Guangming; Zhang, David

2016-01-01

The three-dimensional shape of the ear has been proven to be a stable candidate for biometric authentication because of its desirable properties such as universality, uniqueness, and permanence. In this paper, a special laser scanner designed for online three-dimensional ear acquisition was described. Based on the dataset collected by our scanner, two novel feature classes were defined from a three-dimensional ear image: the global feature class (empty centers and angles) and local feature class (points, lines, and areas). These features are extracted and combined in an optimal way for three-dimensional ear recognition. Using a large dataset consisting of 2,000 samples, the experimental results illustrate the effectiveness of fusing global and local features, obtaining an equal error rate of 2.2%. PMID:27935955

Preschool enrollment is associated with lower odds of childhood obesity among WIC participants in LA County.

PubMed

Koleilat, Maria; Harrison, Gail G; Whaley, Shannon; McGregor, Samar; Jenks, Eloise; Afifi, Abdelmonem

2012-04-01

The prevalence of obesity among children in the United States has increased rapidly during the past few decades. Research into social and behavioral determinants of obesity could lead to innovative strategies for prevention. The objective of the present study was to examine the association between childhood obesity and preschool enrollment and number of hours in child care among low-income preschool-aged children who were participants in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC). We conducted a case-control study including 556 3- to 4-year-old children who were either obese (BMI > 95th percentile of reference standard) or normal-weight (BMI 25-75th percentile). The population was largely (96%) Hispanic, an ethnic group that has one of the highest rates of overweight and obesity in adults and children in the US. In multiple logistic regression analysis, controlling for a variety of psychosocial and cognitive home environment variables, key demographics and maternal variables, the odds ratio of being obese was 0.61 for children who attended preschool more than 4 days a week (95% CI: 0.41-0.90). Watching television or videos for an hour or more on a typical day (odds ratio 1.71 (95% CI 1.07-2.75)), and higher maternal BMI (odds ratio 1.08 (95% CI 1.05-1.11)) were independently related to odds of obesity. The impact of preschool attendance and TV viewing are potentially instructive in terms of preventive interventions for children at this age.

Preface

NASA Astrophysics Data System (ADS)

Matveev, Vladimir S.; Miranda, Eva; Rubtsov, Vladimir; Przybylska, Maria; Tabachnikov, Sergei

2017-05-01

This Special Issue of Journal of Geometry and Physics gathers several contributions to the conference FDIS 2015 3-rd Conference on Finite Dimensional Integrable Systems in Geometry and Mathematical Physics which took place in Będlewo in July 12 to 17, 2015. It also contains other contributions by specialists in the field of integrable systems and related subjects. This is the second special issue which corresponds to the third installment of a series of Workshops called FDIS, which take place every other year.

Rich interfacial chemistry and properties of carbon-doped hexagonal boron nitride nanosheets revealed by electronic structure calculations

NASA Astrophysics Data System (ADS)

Xie, Wei; Tamura, Takahiro; Yanase, Takashi; Nagahama, Taro; Shimada, Toshihiro

2018-04-01

The effect of C doping to hexagonal boron nitride (h-BN) to its electronic structure is examined by first principles calculations using the association from π-electron systems of organic molecules embedded in a two-dimensional insulator. In a monolayered carbon-doped structure, odd-number doping with carbon atoms confers metallic properties with different work functions. Various electronic interactions occur between two layers with odd-number carbon substitution. A direct sp3 covalent chemical bond is formed when C replaces adjacent B and N in different layers. A charge transfer complex between layers is found when C replaces B and N in the next-neighboring region, which results in narrower band gaps (e.g., 0.37 eV). Direct bonding between C and B atoms is found when two C atoms in different layers are at a certain distance.

Dimensions of Oppositional Defiant Disorder in Young Children: Heterotypic Continuity with Anxiety and Depression

PubMed Central

Lavigne, John V.; Gouze, Karen R.; Bryant, Fred B.; Hopkins, Joyce

2014-01-01

There are distinct dimensions of Oppositional Defiant Disorder (ODD) that have been associated with symptoms of other disorders (heterotypic continuity). The present study compared the heterotypic continuity of a two-factor (Pitt-2) model and the three-factor model incorporated into DSM-5 with symptoms of anxiety and depression. Participants were a diverse community sample of 796 children (38.8% minority, 49.1% boys) assessed at ages 4, 5 and 6 years. Symptoms were assessed with the dimensional scales of the Diagnostic Interview Schedule for Children-Young Child version and the Child Symptom Inventory. Dimensions of both the two- and three-factor DSM-5 models were associated with later symptoms of anxiety and depression. The association, however, was weak when accounting for initial levels of internalizing symptoms: thus there was little evidence for the unique contributions of ODD dimensions to symptoms of subsequent internalizing disorders for either model. PMID:24497230

Electrically controllable spin filtering based on superconducting helical states

NASA Astrophysics Data System (ADS)

Bobkova, I. V.; Bobkov, A. M.

2017-12-01

The magnetoelectric effects in the surface states of the three-dimensional (3D) topological insulator (TI) are extremely strong due to the full spin-momentum locking. Here the microscopic theory of S/3D TI bilayer structures in terms of quasiclassical Green's functions is developed. On the basis of the developed formalism it is shown that the DOS in the S/TI bilayer manifests giant magnetoelectric behavior and, as a result, S/3D TI heterostructures can work as nonmagnetic fully electrically controllable spin filters. It is shown that due to the full spin-momentum locking the amplitudes of the odd-frequency singlet and triplet components of the condensate wave function are equal. The same is valid for the even frequency singlet and triplet components. We unveil the connection between the odd-frequency pairing in S/3D TI heterostructures and magnetoelectric effects in the DOS.

Lax representations for matrix short pulse equations

NASA Astrophysics Data System (ADS)

Popowicz, Z.

2017-10-01

The Lax representation for different matrix generalizations of Short Pulse Equations (SPEs) is considered. The four-dimensional Lax representations of four-component Matsuno, Feng, and Dimakis-Müller-Hoissen-Matsuno equations are obtained. The four-component Feng system is defined by generalization of the two-dimensional Lax representation to the four-component case. This system reduces to the original Feng equation, to the two-component Matsuno equation, or to the Yao-Zang equation. The three-component version of the Feng equation is presented. The four-component version of the Matsuno equation with its Lax representation is given. This equation reduces the new two-component Feng system. The two-component Dimakis-Müller-Hoissen-Matsuno equations are generalized to the four-parameter family of the four-component SPE. The bi-Hamiltonian structure of this generalization, for special values of parameters, is defined. This four-component SPE in special cases reduces to the new two-component SPE.

Aspects of QCD current algebra on a null plane

NASA Astrophysics Data System (ADS)

Beane, S. R.; Hobbs, T. J.

2016-09-01

Consequences of QCD current algebra formulated on a light-like hyperplane are derived for the forward scattering of vector and axial-vector currents on an arbitrary hadronic target. It is shown that current algebra gives rise to a special class of sum rules that are direct consequences of the independent chiral symmetry that exists at every point on the two-dimensional transverse plane orthogonal to the lightlike direction. These sum rules are obtained by exploiting the closed, infinite-dimensional algebra satisfied by the transverse moments of null-plane axial-vector and vector charge distributions. In the special case of a nucleon target, this procedure leads to the Adler-Weisberger, Gerasimov-Drell-Hearn, Cabibbo-Radicati and Fubini-Furlan-Rossetti sum rules. Matching to the dispersion-theoretic language which is usually invoked in deriving these sum rules, the moment sum rules are shown to be equivalent to algebraic constraints on forward S-matrix elements in the Regge limit.

One-Dimensional Nanostructures and Devices of II–V Group Semiconductors

PubMed Central

2009-01-01

The II–V group semiconductors, with narrow band gaps, are important materials with many applications in infrared detectors, lasers, solar cells, ultrasonic multipliers, and Hall generators. Since the first report on trumpet-like Zn3P2nanowires, one-dimensional (1-D) nanostructures of II–V group semiconductors have attracted great research attention recently because these special 1-D nanostructures may find applications in fabricating new electronic and optoelectronic nanoscale devices. This article covers the 1-D II–V semiconducting nanostructures that have been synthesized till now, focusing on nanotubes, nanowires, nanobelts, and special nanostructures like heterostructured nanowires. Novel electronic and optoelectronic devices built on 1-D II–V semiconducting nanostructures will also be discussed, which include metal–insulator-semiconductor field-effect transistors, metal-semiconductor field-effect transistors, andp–nheterojunction photodiode. We intent to provide the readers a brief account of these exciting research activities. PMID:20596452

Holographic digital microscopy in on-line process control

NASA Astrophysics Data System (ADS)

Osanlou, Ardeshir

2011-09-01

This article investigates the feasibility of real-time three-dimensional imaging of microscopic objects within various emulsions while being produced in specialized production vessels. The study is particularly relevant to on-line process monitoring and control in chemical, pharmaceutical, food, cleaning, and personal hygiene industries. Such processes are often dynamic and the materials cannot be measured once removed from the production vessel. The technique reported here is applicable to three-dimensional characterization analyses on stirred fluids in small reaction vessels. Relatively expensive pulsed lasers have been avoided through the careful control of the speed of the moving fluid in relation to the speed of the camera exposure and the wavelength of the continuous wave laser used. The ultimate aim of the project is to introduce a fully robust and compact digital holographic microscope as a process control tool in a full size specialized production vessel.

Visualizing curved spacetime

NASA Astrophysics Data System (ADS)

Jonsson, Rickard M.

2005-03-01

I present a way to visualize the concept of curved spacetime. The result is a curved surface with local coordinate systems (Minkowski systems) living on it, giving the local directions of space and time. Relative to these systems, special relativity holds. The method can be used to visualize gravitational time dilation, the horizon of black holes, and cosmological models. The idea underlying the illustrations is first to specify a field of timelike four-velocities uμ. Then, at every point, one performs a coordinate transformation to a local Minkowski system comoving with the given four-velocity. In the local system, the sign of the spatial part of the metric is flipped to create a new metric of Euclidean signature. The new positive definite metric, called the absolute metric, can be covariantly related to the original Lorentzian metric. For the special case of a two-dimensional original metric, the absolute metric may be embedded in three-dimensional Euclidean space as a curved surface.

Lump-type solutions for the (4+1)-dimensional Fokas equation via symbolic computations

NASA Astrophysics Data System (ADS)

Cheng, Li; Zhang, Yi

2017-09-01

Based on the Hirota bilinear form, two classes of lump-type solutions of the (4+1)-dimensional nonlinear Fokas equation, rationally localized in almost all directions in the space are obtained through a direct symbolic computation with Maple. The resulting lump-type solutions contain free parameters. To guarantee the analyticity and rational localization of the solutions, the involved parameters need to satisfy certain constraints. A few particular lump-type solutions with special choices of the involved parameters are given.

One-dimensional Coulomb problem in Dirac materials

NASA Astrophysics Data System (ADS)

Downing, C. A.; Portnoi, M. E.

2014-11-01

We investigate the one-dimensional Coulomb potential with application to a class of quasirelativistic systems, so-called Dirac-Weyl materials, described by matrix Hamiltonians. We obtain the exact solution of the shifted and truncated Coulomb problems, with the wave functions expressed in terms of special functions (namely, Whittaker functions), while the energy spectrum must be determined via solutions to transcendental equations. Most notably, there are critical band gaps below which certain low-lying quantum states are missing in a manifestation of atomic collapse.

Two-Dimensional One-Component Plasma on Flamm's Paraboloid

NASA Astrophysics Data System (ADS)

Fantoni, Riccardo; Téllez, Gabriel

2008-11-01

We study the classical non-relativistic two-dimensional one-component plasma at Coulomb coupling Γ=2 on the Riemannian surface known as Flamm's paraboloid which is obtained from the spatial part of the Schwarzschild metric. At this special value of the coupling constant, the statistical mechanics of the system are exactly solvable analytically. The Helmholtz free energy asymptotic expansion for the large system has been found. The density of the plasma, in the thermodynamic limit, has been carefully studied in various situations.

G-structures and domain walls in heterotic theories

NASA Astrophysics Data System (ADS)

Lukas, Andre; Matti, Cyril

2011-01-01

We consider heterotic string solutions based on a warped product of a four-dimensional domain wall and a six-dimensional internal manifold, preserving two supercharges. The constraints on the internal manifolds with SU(3) structure are derived. They are found to be generalized half-flat manifolds with a particular pattern of torsion classes and they include half-flat manifolds and Strominger's complex non-Kahler manifolds as special cases. We also verify that previous heterotic compactifications on half-flat mirror manifolds are based on this class of solutions.

Abdominal tumours in children: 3-D visualisation and surgical planning.

PubMed

Günther, P; Schenk, J P; Wunsch, R; Tröger, J; Waag, K L

2004-10-01

Solid abdominal tumours are of special importance in the field of paediatric surgery. Because of the dangers of cumulative irradiation and improved delineation of soft parts MRI is usually employed in children for diagnostic assessment. Compiling the radiologic information for surgical planning is often difficult by conventional methods. Newly improved and efficient 3-D volume rendering software is now available for visual reconstruction of tumour anatomy utilising segmentation and other special techniques. Because the intraoperative complication rate is close to 20 % as described in the literature, optimal preoperative visualisation and planning would seem imperative. All children with solid abdominal tumours at Heidelberg University in the year 2002 were included in this study. MR examinations were performed with a 0.5 Tesla magnet using a standard protocol. All MR data were processed with VG Studio Max 1.1, converting the two-dimensional data into three-dimensional data. This report presents 15 cases using this special technique: 7 with abdominal neuroblastoma, 6 with nephroblastoma, 1 ganglioneuroma, and 1 ovarian teratoma. Our experience shows that a better understanding of the surgical anatomy, particularly regarding the surrounding organs and vasculature, can be helpful in decreasing the incidence of inadvertent intraoperative injuries to these structures.

Work-related violence, lifestyle, and health among special education teachers working in Finnish basic education.

PubMed

Ervasti, Jenni; Kivimäki, Mika; Pentti, Jaana; Salmi, Venla; Suominen, Sakari; Vahtera, Jussi; Virtanen, Marianna

2012-07-01

Studies have reported higher levels of absenteeism due to illness among special education teachers compared to other teachers, but it is not known which factors might contribute to this difference. We examined whether health, health behaviors, and exposure to violence at work differed between special education and general education teachers in Finnish basic education. Survey data from 5760 general and special education teachers were analyzed with multilevel logistic models adjusted for individual- and school-level confounding factors. No difference was found between the health behaviors of general and special education teachers. The differences in physical and mental health between the two groups were also relatively small. With regard to work-related violence, however, male special education teachers were 3 times more likely to be exposed to mental abuse, and 5 times more likely to be exposed to physical violence when compared to their male colleagues in general education. Although female special educators were also at an increased risk of mental abuse and physical violence compared to their female general teacher colleagues, their odds ratios for such an encounter were smaller (2- and 3-fold, respectively) than those of male special education teachers. The school-level variance of physical violence toward teachers was large, which indicates that while most schools have little physical violence toward teachers, schools do exist in which teachers' exposure to violence is common. These findings suggest that special education teachers may benefit from training for handling violent situations and interventions to prevent violence at schools. © 2012, American School Health Association.

A three-dimensional total odd nitrogen (NO y ) simulation during SONEX using a stretched-grid chemical transport model

NASA Astrophysics Data System (ADS)

Allen, Dale; Pickering, Kenneth; Stenchikov, Georgiy; Thompson, Anne; Kondo, Yutaka

2000-02-01

The relative importance of various odd nitrogen (NOy) sources including lightning, aircraft, and surface emissions on upper tropospheric total odd nitrogen is illustrated as a first application of the three-dimensional Stretched-Grid University of Maryland/Goddard Chemical-Transport Model (SG-GCTM). The SG-GCTM has been developed to look at the effect of localized sources and/or small-scale mixing processes on the large-scale or global chemical balance. For this simulation the stretched grid was chosen so that its maximum resolution is located over eastern North America and the North Atlantic; a region that includes most of the Subsonic Assessment (SASS) Ozone and Nitrogen Oxide Experiment (SONEX) flight paths. The SONEX period (October-November 1997) is simulated by driving the SG-GCTM with assimilated data from the Goddard Earth Observing System-Stratospheric Tracers of Atmospheric Transport Data Assimilation System (GEOS-STRAT DAS). A new algorithm is used to estimate the lightning flash rates needed to calculate NOy emission by lightning. This algorithm parameterizes the flash rate in terms of upper tropospheric convective mass flux. Model-calculated upper tropospheric NOy and NOy measurements from the NASA DC-8 aircraft are compared. Spatial variations in NOy were well captured especially with the stretched-grid run; however, model-calculated peaks due to "stratospheric" NOy are occasionally too large. The lightning algorithm reproduces the temporally and spatially averaged total flash rate accurately; however, the use of emissions from observed lightning flashes significantly improves the simulation on a few days, especially November 3, 1997, showing that significant uncertainty remains in parameterizing lightning in chemistry and transport models. Aircraft emissions contributed ˜15% of the upper tropospheric NOy averaged along SONEX flight paths within the North Atlantic Flight Corridor with the contribution exceeding 40% during portions of some flights.

Evaluation of drought using SPEI drought class transitions and log-linear models for different agro-ecological regions of India

NASA Astrophysics Data System (ADS)

Alam, N. M.; Sharma, G. C.; Moreira, Elsa; Jana, C.; Mishra, P. K.; Sharma, N. K.; Mandal, D.

2017-08-01

Markov chain and 3-dimensional log-linear models were attempted to model drought class transitions derived from the newly developed drought index the Standardized Precipitation Evapotranspiration Index (SPEI) at a 12 month time scale for six major drought prone areas of India. Log-linear modelling approach has been used to investigate differences relative to drought class transitions using SPEI-12 time series derived form 48 yeas monthly rainfall and temperature data. In this study, the probabilities of drought class transition, the mean residence time, the 1, 2 or 3 months ahead prediction of average transition time between drought classes and the drought severity class have been derived. Seasonality of precipitation has been derived for non-homogeneous Markov chains which could be used to explain the effect of the potential retreat of drought. Quasi-association and Quasi-symmetry log-linear models have been fitted to the drought class transitions derived from SPEI-12 time series. The estimates of odds along with their confidence intervals were obtained to explain the progression of drought and estimation of drought class transition probabilities. For initial months as the drought severity increases the calculated odds shows lower value and the odds decreases for the succeeding months. This indicates that the ratio of expected frequencies of occurrence of transition from drought class to the non-drought class decreases as compared to transition to any drought class when the drought severity of the present class increases. From 3-dimensional log-linear model it is clear that during the last 24 years the drought probability has increased for almost all the six regions. The findings from the present study will immensely help to assess the impact of drought on the gross primary production and to develop future contingent planning in similar regions worldwide.

A longitudinal study of food insecurity on obesity in preschool children.

PubMed

Metallinos-Katsaras, Elizabeth; Must, Aviva; Gorman, Kathleen

2012-12-01

Obesity and its co-occurrence with household food insecurity among low-income families is a public health concern, particularly because both are associated with later adverse health consequences. Our aim was to examine the relationship between household food insecurity with and without hunger in infancy and later childhood with weight status at 2 to 5 years. This longitudinal study uses household food-security status, weight, and height data collected at the first infancy and last child (2 to 5 years) Special Supplemental Nutrition Program for Women, Infants, and Children visits. Household food security was based on parent/caretaker responses to a four-question subscale of the 18-item Core Food Security Module. Obesity was defined as sex-specific body mass index for age ≥ 95th percentile. A diverse (58.6% non-white) low-income sample of 28,353 children participating in the Massachusetts Special Supplemental Nutrition Program for Women, Infants, and Children (2001-2006); 24.9% of infants and 23.1% of children lived in food-insecure households and 17.1% were obese at their last child visit. Multivariate logistic regression analyses assessed the association between household food-security status during the infant and child visits, and risk of preschool obesity, while controlling for child race/Hispanic ethnicity, sex, child and household size, maternal age, education, and prepregnancy weight. Interactions between these covariates and household food-security status were also examined. In cases of multiple comparisons, a Bonferroni correction was applied. Persistent household food insecurity without hunger was associated with 22% greater odds of child obesity (odds ratio=1.22; 95% CI 1.06 to 1.41) compared with those persistently food secure (P<0.05). Maternal prepregnancy weight status modified this association with children of underweight (adjusted odds ratio=3.22; 95% CI 1.70 to 6.11; P=0.003) or overweight/obese (adjusted odds ratio=1.34; 95% CI 1.11 to 1.62; P=0.03) mothers experiencing greater odds of child obesity with persistent household food insecurity without hunger compared with those with persistent household food security. These results suggest that persistent household food insecurity without hunger is prospectively related to child obesity, but that these associations depend on maternal weight status. Vulnerable groups should be targeted for early interventions to prevent overweight and obesity later in life. Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Obesity and functional impairment: influence of comorbidity, joint pain, and mental health.

PubMed

Heo, Moonseong; Pietrobelli, Angelo; Wang, Dan; Heymsfield, Steven B; Faith, Myles S

2010-10-01

To examine the relationship between obesity and functional impairment and the influence of comorbidity, joint pain, and mental health on this association, we used US adult respondents (N = 430,912) to the 2007 Behavioral Risk Factor Surveillance Survey (BRFSS-07). Functional impairment was indicated if a respondent was either (i) limited in any way or in any activities because of physical, mental, or emotional problems, or (ii) had any health problem that required using special equipment such as a cane, wheelchair, special bed, or special telephone. Approximately 62.8% of respondents were overweight or obese and 20.3% were functionally impaired. The unadjusted relationship between obesity and functional impairment revealed a classical J-shaped pattern with odds ratios (95% confidence interval) compared to the normal weight group: 1.63 (1.54-1.73), 1.22 (1.20-1.25), 1.77 (1.73-1.81), 2.43 (2.36-2.51), and 4.12 (3.97-4.27) for underweight, overweight, obesity class I, II, and III, respectively. Although inclusion of different combinations of sociodemographic and medical covariates substantially attenuated the unadjusted association, the collective inclusion of all covariates in a single model did not eliminate the significant J-shaped association resulting in the following corresponding adjusted odds ratios: 1.19 (1.13-1.25), 1.01 (0.99-1.04), 1.23 (1.19-1.27), 1.38 (1.32-1.44), and 1.92 (1.82-2.02). The attenuation was mostly influenced by medical comorbidity. In conclusion, functional impairment is associated with obesity, primarily due to medical comorbidity conditions. The significant residual association highlights the importance of sustainable obesity prevention and treatment at both the individual and public level as functional impairment can create burdens at individual, familial, and societal levels.

A randomized controlled trial of comprehensive early intervention care in patients with first-episode psychosis in Japan: 1.5-year outcomes from the J-CAP study.

PubMed

Nishida, Atsushi; Ando, Shuntaro; Yamasaki, Syudo; Koike, Shinsuke; Ichihashi, Kayo; Miyakoshi, Yuji; Maekawa, Sanae; Nakamura, Tomohisa; Natsubori, Tatsunobu; Ichikawa, Eriko; Ishigami, Hiroki; Sato, Kojiro; Matsunaga, Asami; Smith, Jo; French, Paul; Harima, Hirohiko; Kishi, Yoshiki; Fujita, Izumi; Kasai, Kiyoto; Okazaki, Yuji

2018-04-08

The first episode of psychosis represents a critical period wherein comprehensive early intervention in psychosis (EIP) may alter the course of illness. However, evidence from randomized controlled trials that have examined the impact of comprehensive EIP care on clinical and functional recovery assessed by independent blinded raters is limited. The objective of this study was to conduct a single-blinded multicenter trial comparing comprehensive EIP care and standard care in young patients with first-episode psychosis (FEP) in Japan (J-CAP Study). A total of 77 participants with FEP (aged 15-35 years) were randomized to receive standard care or specialized comprehensive EIP care and were followed up for 1.5 years (trial no.: UMIN000005092). Function (measured with the Global Assessment of Functioning) and clinical remission (defined by internationally standardized criteria proposed by the Remission in Schizophrenia Working Group) were evaluated by independent raters who were blinded to group assignment. Dropout rate and other secondary outcomes were also examined. The specialized EIP care group had a higher clinical remission rate (odds ratio, 6.3; 95% confidence interval, 1.0-37.9) and lower treatment dropout rate (odds ratio, 0.038; 95% confidence interval, 0.002-0.923) than the standard care group, even after adjusting for baseline characteristics. Functional improvement in the specialized EIP care group was slightly higher than that in the standard care group, but this difference was not statistically significant (p = 0.195). From the results, we conclude that comprehensive EIP care may provide advantages over standard care in patients with FEP. Copyright © 2018. Published by Elsevier Ltd.

Dynamical topology and statistical properties of spatiotemporal chaos.

PubMed

Zhuang, Quntao; Gao, Xun; Ouyang, Qi; Wang, Hongli

2012-12-01

For spatiotemporal chaos described by partial differential equations, there are generally locations where the dynamical variable achieves its local extremum or where the time partial derivative of the variable vanishes instantaneously. To a large extent, the location and movement of these topologically special points determine the qualitative structure of the disordered states. We analyze numerically statistical properties of the topologically special points in one-dimensional spatiotemporal chaos. The probability distribution functions for the number of point, the lifespan, and the distance covered during their lifetime are obtained from numerical simulations. Mathematically, we establish a probabilistic model to describe the dynamics of these topologically special points. In spite of the different definitions in different spatiotemporal chaos, the dynamics of these special points can be described in a uniform approach.

Note on cosmological Levi-Civita spacetimes in higher dimensions

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

Sarioglu, Oezguer; Tekin, Bayram

2009-04-15

We find a class of solutions to cosmological Einstein equations that generalizes the four dimensional cylindrically symmetric spacetimes to higher dimensions. The AdS soliton is a special member of this class with a unique singularity structure.

Global well-posedness of three-dimensional Navier-Stokes equations with partial viscosity under helical symmetry

NASA Astrophysics Data System (ADS)

Liu, Jitao; Niu, Dongjuan

2017-06-01

In this paper, we investigate the global well-posedness of three-dimensional Navier-Stokes equations with horizontal viscosity under a special symmetric structure: helical symmetry. More precisely, by a revised Ladyzhenskaya-type inequality and utilizing the behavior of helical flows, we prove the global existence and uniqueness of weak and strong solutions to the three-dimensional helical flows. Our result reveals that for the issue of global well-posedness of the viscous helical flows, the horizontal viscosity plays the important role. To some extent, our work can be seen as a generalization of the result by Mahalov et al. (Arch Ration Mech Anal 112(3):193-222, 1990).

Rigorous Free-Fermion Entanglement Renormalization from Wavelet Theory

NASA Astrophysics Data System (ADS)

Haegeman, Jutho; Swingle, Brian; Walter, Michael; Cotler, Jordan; Evenbly, Glen; Scholz, Volkher B.

2018-01-01

We construct entanglement renormalization schemes that provably approximate the ground states of noninteracting-fermion nearest-neighbor hopping Hamiltonians on the one-dimensional discrete line and the two-dimensional square lattice. These schemes give hierarchical quantum circuits that build up the states from unentangled degrees of freedom. The circuits are based on pairs of discrete wavelet transforms, which are approximately related by a "half-shift": translation by half a unit cell. The presence of the Fermi surface in the two-dimensional model requires a special kind of circuit architecture to properly capture the entanglement in the ground state. We show how the error in the approximation can be controlled without ever performing a variational optimization.

Web-based segmentation and display of three-dimensional radiologic image data.

PubMed

Silverstein, J; Rubenstein, J; Millman, A; Panko, W

1998-01-01

In many clinical circumstances, viewing sequential radiological image data as three-dimensional models is proving beneficial. However, designing customized computer-generated radiological models is beyond the scope of most physicians, due to specialized hardware and software requirements. We have created a simple method for Internet users to remotely construct and locally display three-dimensional radiological models using only a standard web browser. Rapid model construction is achieved by distributing the hardware intensive steps to a remote server. Once created, the model is automatically displayed on the requesting browser and is accessible to multiple geographically distributed users. Implementation of our server software on large scale systems could be of great service to the worldwide medical community.

Uncertainty relations for angular momentum eigenstates in two and three spatial dimensions

NASA Astrophysics Data System (ADS)

Bracher, Christian

2011-03-01

I reexamine Heisenberg's uncertainty relation for two- and three-dimensional wave packets with fixed angular momentum quantum numbers m or ℓ. A simple proof shows that the product of the average extent Δr and Δp of a two-dimensional wave packet in position and momentum space is bounded from below by ΔrΔp ≥ℏ(|m|+1). The minimum uncertainty is attained by modified Gaussian wave packets that are special eigenstates of the two-dimensional isotropic harmonic oscillator, which include the ground states of electrons in a uniform magnetic field. Similarly, the inequality ΔrΔp ≥ℏ(ℓ +3/2) holds for three-dimensional wave packets with fixed total angular momentum ℓ and the equality holds for a Gaussian radial profile. I also discuss some applications of these uncertainty relations.

Questions on universal constants and four-dimensional symmetry from a broad viewpoint. I

NASA Technical Reports Server (NTRS)

Hsu, J. P.

1983-01-01

It is demonstrated that there is a flexibility in clock synchronizations and that four-dimensional symmetry framework can be viewed broadly. The true universality of basic constants is discussed, considering a class of measurement processes based on the velocity = distance/time interval, which always yields some number when used by an observer. The four-dimensional symmetry framework based on common time for all observers is formulated, and related processes of measuring light speed are discussed. Invariant 'action functions' for physical laws in the new four-dimensional symmetry framework with the common time are established to discuss universal constants. Truly universal constants are demonstrated, and it is shown that physics in this new framework and in special relativity are equivalent as far as one-particle systems and the S-matrix in field theories are concerned.

Like-charge attraction in a one-dimensional setting: the importance of being odd

NASA Astrophysics Data System (ADS)

Trizac, Emmanuel; Téllez, Gabriel

2018-03-01

From cement cohesion to DNA condensation, a proper statistical physics treatment of systems with long-range forces is important for a number of applications in physics, chemistry, and biology. We compute here the effective force between fixed charged macromolecules, screened by oppositely charged mobile ions (counterions). We treat the problem in a one-dimensional configuration that allows for interesting discussion and derivation of exact results, remaining at a level of mathematical difficulty compatible with an undergraduate course. Emphasis is put on the counterintuitive but fundamental phenomenon of like-charge attraction, which our treatment brings for the first time to the level of undergraduate teaching. The parity of the number of counterions is shown to play a prominent role, which sheds light on the binding mechanism at work when like-charge macromolecules do attract.

Special effects used in creating 3D animated scenes-part 1

NASA Astrophysics Data System (ADS)

Avramescu, A. M.

2015-11-01

In present, with the help of computer, we can create special effects that look so real that we almost don't perceive them as being different. These special effects are somehow hard to differentiate from the real elements like those on the screen. With the increasingly accesible 3D field that has more and more areas of application, the 3D technology goes easily from architecture to product designing. Real like 3D animations are used as means of learning, for multimedia presentations of big global corporations, for special effects and even for virtual actors in movies. Technology, as part of the movie art, is considered a prerequisite but the cinematography is the first art that had to wait for the correct intersection of technological development, innovation and human vision in order to attain full achievement. Increasingly more often, the majority of industries is using 3D sequences (three dimensional). 3D represented graphics, commercials and special effects from movies are all designed in 3D. The key for attaining real visual effects is to successfully combine various distinct elements: characters, objects, images and video scenes; like all these elements represent a whole that works in perfect harmony. This article aims to exhibit a game design from these days. Considering the advanced technology and futuristic vision of designers, nowadays we have different and multifarious game models. Special effects are decisively contributing in the creation of a realistic three-dimensional scene. These effects are essential for transmitting the emotional state of the scene. Creating the special effects is a work of finesse in order to achieve high quality scenes. Special effects can be used to get the attention of the onlooker on an object from a scene. Out of the conducted study, the best-selling game of the year 2010 was Call of Duty: Modern Warfare 2. This way, the article aims for the presented scene to be similar with many locations from this type of games, more precisely, a place from the Middle East, a very popular subject among game developers.

High definition versus standard definition white light endoscopy for detecting dysplasia in patients with Barrett's esophagus.

PubMed

Sami, S S; Subramanian, V; Butt, W M; Bejkar, G; Coleman, J; Mannath, J; Ragunath, K

2015-01-01

High-definition endoscopy systems provide superior image resolution. The aim of this study was to assess the utility of high definition compared with standard definition endoscopy system for detecting dysplastic lesions in patients with Barrett's esophagus. A retrospective cohort study of patients with non-dysplastic Barrett's esophagus undergoing routine surveillance was performed. Data were retrieved from the central hospital electronic database. Procedures performed for non-surveillance indications, Barrett's esophagus Prague C0M1 classification with no specialized intestinal metaplasia on histology, patients diagnosed with any dysplasia or cancer on index endoscopy, and procedures using advanced imaging techniques were excluded. Logistic regression models were constructed to estimate adjusted odds ratios and 95% confidence intervals comparing outcomes with standard definition and high-definition systems. The high definition was superior to standard definition system in targeted detection of all dysplastic lesions (odds ratio 3.27, 95% confidence interval 1.27-8.40) as well as overall dysplasia detected on both random and target biopsies (odds ratio 2.36, 95% confidence interval 1.50-3.72). More non-dysplastic lesions were detected with the high-definition system (odds ratio 1.16, 95% confidence interval 1.01-1.33). There was no difference between high definition and standard definition endoscopy in the overall (random and target) high-grade dysplasia or cancers detected (odds ratio 0.93, 95% confidence interval 0.83-1.04). Trainee endoscopists, number of biopsies taken, and male sex were all significantly associated with a higher yield for dysplastic lesions. The use of the high-definition endoscopy system is associated with better targeted detection of any dysplasia during routine Barrett's esophagus surveillance. However, high-definition endoscopy cannot replace random biopsies at present time. © 2014 International Society for Diseases of the Esophagus.

Recent advances in aptasensors based on graphene and graphene-like nanomaterials.

PubMed

Ping, Jianfeng; Zhou, Yubin; Wu, Yuanyuan; Papper, Vladislav; Boujday, Souhir; Marks, Robert S; Steele, Terry W J

2015-02-15

Graphene and graphene-like two-dimensional nanomaterials have aroused tremendous research interest in recent years due to their unique electronic, optical, and mechanical properties associated with their planar structure. Aptamers have exhibited many advantages as molecular recognition elements for sensing devices compared to traditional antibodies. The marriage of two-dimensional nanomaterials and aptamers has emerged many ingenious aptasensing strategies for applications in the fields of clinical diagnosis and food safety. This review highlights current advances in the development and application of two-dimensional nanomaterials-based aptasensors with the focus on two main signal-transducing mechanisms, i.e. electrochemical and optical. A special attention is paid to graphene, a one-atom thick layer of graphite with exceptional properties, representing a fastgrowing field of research. In view of the unique properties of two-dimensional nanostructures and their inherent advantages of synthetic aptamers, we expect that high-performance two-dimensional nanomaterials-based aptasensing devices will find extensive applications in environmental monitoring, biomedical diagnostics, and food safety. Copyright © 2014 Elsevier B.V. All rights reserved.

On the geometry of the space-time and motion of the spinning bodies

NASA Astrophysics Data System (ADS)

Trenčevski, Kostadin

2013-03-01

In this paper an alternative theory about space-time is given. First some preliminaries about 3-dimensional time and the reasons for its introduction are presented. Alongside the 3-dimensional space (S) the 3-dimensional space of spatial rotations (SR) is considered independently from the 3-dimensional space. Then it is given a model of the universe, based on the Lie groups of real and complex orthogonal 3 × 3 matrices in this 3+3+3-dimensional space. Special attention is dedicated for introduction and study of the space S × SR, which appears to be isomorphic to SO(3,ℝ) × SO(3,ℝ) or S 3 × S 3. The influence of the gravitational acceleration to the spinning bodies is considered. Some important applications of these results about spinning bodies are given, which naturally lead to violation of Newton's third law in its classical formulation. The precession of the spinning axis is also considered.

Online service for monitoring the ionosphere based on data from the global navigation satellite system

NASA Astrophysics Data System (ADS)

Aleshin, I. M.; Alpatov, V. V.; Vasil'ev, A. E.; Burguchev, S. S.; Kholodkov, K. I.; Budnikov, P. A.; Molodtsov, D. A.; Koryagin, V. N.; Perederin, F. V.

2014-07-01

A service is described that makes possible the effective construction of a three-dimensional ionospheric model based on the data of ground receivers of signals from global navigation satellite positioning systems (GNSS). The obtained image has a high resolution, mainly because data from the IPG GNSS network of the Federal Service for Hydrometeorology and Environmental Monitoring (Rosgidromet) are used. A specially developed format and its implementation in the form of SQL structures are used to collect, transmit, and store data. The method of high-altitude radio tomography is used to construct the three-dimensional model. The operation of all system components (from registration point organization to the procedure for constructing the electron density three-dimensional distribution and publication of the total electron content map on the Internet) has been described in detail. The three-dimensional image of the ionosphere, obtained automatically, is compared with the ionosonde measurements, calculated using the two-dimensional low-altitude tomography method and averaged by the ionospheric model.

A VERSATILE SHARP INTERFACE IMMERSED BOUNDARY METHOD FOR INCOMPRESSIBLE FLOWS WITH COMPLEX BOUNDARIES

PubMed Central

Mittal, R.; Dong, H.; Bozkurttas, M.; Najjar, F.M.; Vargas, A.; von Loebbecke, A.

2010-01-01

A sharp interface immersed boundary method for simulating incompressible viscous flow past three-dimensional immersed bodies is described. The method employs a multi-dimensional ghost-cell methodology to satisfy the boundary conditions on the immersed boundary and the method is designed to handle highly complex three-dimensional, stationary, moving and/or deforming bodies. The complex immersed surfaces are represented by grids consisting of unstructured triangular elements; while the flow is computed on non-uniform Cartesian grids. The paper describes the salient features of the methodology with special emphasis on the immersed boundary treatment for stationary and moving boundaries. Simulations of a number of canonical two- and three-dimensional flows are used to verify the accuracy and fidelity of the solver over a range of Reynolds numbers. Flow past suddenly accelerated bodies are used to validate the solver for moving boundary problems. Finally two cases inspired from biology with highly complex three-dimensional bodies are simulated in order to demonstrate the versatility of the method. PMID:20216919

Growth after late-preterm birth and adult cognitive, academic, and mental health outcomes.

PubMed

Sammallahti, Sara; Heinonen, Kati; Andersson, Sture; Lahti, Marius; Pirkola, Sami; Lahti, Jari; Pesonen, Anu-Katriina; Lano, Aulikki; Wolke, Dieter; Eriksson, Johan G; Kajantie, Eero; Raikkonen, Katri

2017-05-01

Late-preterm birth (at 34 0⁄7 -36 6⁄7 wk gestation) increases the risk of early growth faltering, poorer neurocognitive functioning, and lower socio-economic attainment. Among early-preterm individuals, faster early growth benefits neurodevelopment, but it remains unknown whether these benefits extend to late-preterm individuals. In 108 late-preterm individuals, we examined if weight, head, or length growth between birth, 5 and 20 months' corrected age, and 56 mo, predicted grade point average and special education in comprehensive school, or neurocognitive abilities and psychiatric diagnoses/symptoms at 24-26 y of age. For every 1 SD faster weight and head growth from birth to 5 mo, and head growth from 5 to 20 mo, participants had 0.19-0.41 SD units higher IQ, executive functioning score, and grade point average (95% confidence intervals (CI) 0.002-0.59 SD), and lower odds of special education (odds ratio (OR) = 0.49-0.59, 95% CIs 0.28-0.97), after adjusting for sex, gestational age, follow-up age, and parental education. Faster head growth from 20 to 56 mo was associated with less internalizing problems; otherwise we found no consistent associations with mental health outcomes. Faster growth during the critical early period after late-preterm birth is associated with better adult neurocognitive functioning, but not consistently with mental health outcomes.

Do flower color and floral scent of silene species affect host preference of Hadena bicruris, a seed-eating pollinator, under field conditions?

PubMed

Page, Paul; Favre, Adrien; Schiestl, Florian P; Karrenberg, Sophie

2014-01-01

Specialization in plant-insect interactions is an important driver of evolutionary divergence; yet, plant traits mediating such interactions are poorly understood. In this study, we investigated how flower color and floral scent are related to seed predation by a seed-eating pollinator. We used field-transplanted recombinant F2 hybrids between Silene latifolia and S. dioica that are the preferred and alternative hosts of the moth Hadena bicruris and crosses within these species for comparison. We scored seed predation and flower color and analyzed floral scent. Pinker S. dioica-like flowers and emission of α-pinene decreased the odds of seed predation while emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation. Emission of these compounds did not differ significantly between the two Silene species. Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia. The compounds α-pinene, benzyl acetate and 6-methyl-5-hepten-2-one could represent non-specific deterrents and attractants to ovipositing moths. Alternatively, emission of these compounds could be related to herbivory or pathogen attack and act as a signal for host quality. This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization.

Do Flower Color and Floral Scent of Silene Species affect Host Preference of Hadena bicruris, a Seed-Eating Pollinator, under Field Conditions?

PubMed Central

Page, Paul; Favre, Adrien; Schiestl, Florian P.; Karrenberg, Sophie

2014-01-01

Specialization in plant–insect interactions is an important driver of evolutionary divergence; yet, plant traits mediating such interactions are poorly understood. In this study, we investigated how flower color and floral scent are related to seed predation by a seed-eating pollinator. We used field-transplanted recombinant F2 hybrids between Silene latifolia and S. dioica that are the preferred and alternative hosts of the moth Hadena bicruris and crosses within these species for comparison. We scored seed predation and flower color and analyzed floral scent. Pinker S. dioica-like flowers and emission of α-pinene decreased the odds of seed predation while emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation. Emission of these compounds did not differ significantly between the two Silene species. Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia. The compounds α-pinene, benzyl acetate and 6-methyl-5-hepten-2-one could represent non-specific deterrents and attractants to ovipositing moths. Alternatively, emission of these compounds could be related to herbivory or pathogen attack and act as a signal for host quality. This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization. PMID:24905986

Therapy Use for Children With Developmental Conditions: Analysis of Colorado Medicaid Data.

PubMed

McManus, Beth M; Rapport, Mary Jane; Richardson, Zachary; Lindrooth, Richard

2017-07-01

To examine therapy use and spending for Medicaid-enrolled infants and toddlers with developmental conditions. Sample infants and toddlers had a diagnosis (eg, cerebral palsy) or developmental delay (DD). Colorado Children's Medicaid administrative outpatient therapy claims (2006-2008) were used to estimate differences, by condition type and number of comorbid chronic conditions (CCCs), of any physical therapy (PT)/occupational therapy (OT) and Medicaid PT/OT spending. The sample included 20 959 children. Children with at least 2 CCCs had higher odds of PT/OT than children with no CCC. Children with DD had 12-fold higher odds of having any PT/OT compared with children with diagnosis. Children with a DD and 2 CCCs had the highest PT/OT spending. Medicaid PT/OT use and spending are higher for children with more CCCs and those with DD because children with DD receive more specialized PT/OT.

Determination of power and moment on shaft of special asynchronous electric drives

NASA Astrophysics Data System (ADS)

Karandey, V. Yu; Popov, B. K.; Popova, O. B.; Afanasyev, V. L.

2018-03-01

In the article, questions and tasks of determination of power and the moment on a shaft of special asynchronous electric drives are considered. Use of special asynchronous electric drives in mechanical engineering and other industries is relevant. The considered types of electric drives possess the improved mass-dimensional indicators in comparison with singleengine systems. Also these types of electric drives have constructive advantages; the improved characteristics allow one to realize the technological process. But creation and design of new electric drives demands adjustment of existing or development of new methods and approaches of calculation of parameters. Determination of power and the moment on a shaft of special asynchronous electric drives is the main objective during design of electric drives. This task has been solved based on a method of electromechanical transformation of energy.

On 3-D inelastic analysis methods for hot section components. Volume 1: Special finite element models

NASA Technical Reports Server (NTRS)

Nakazawa, S.

1987-01-01

This Annual Status Report presents the results of work performed during the third year of the 3-D Inelastic Analysis Methods for Hot Section Components program (NASA Contract NAS3-23697). The objective of the program is to produce a series of new computer codes that permit more accurate and efficient three-dimensional analysis of selected hot section components, i.e., combustor liners, turbine blades, and turbine vanes. The computer codes embody a progression of mathematical models and are streamlined to take advantage of geometrical features, loading conditions, and forms of material response that distinguish each group of selected components. This report is presented in two volumes. Volume 1 describes effort performed under Task 4B, Special Finite Element Special Function Models, while Volume 2 concentrates on Task 4C, Advanced Special Functions Models.

Modeling digital pulse waveforms by solving one-dimensional Navier-stokes equations.

PubMed

Fedotov, Aleksandr A; Akulova, Anna S; Akulov, Sergey A

2016-08-01

Mathematical modeling for composition distal arterial pulse wave in the blood vessels of the upper limbs was considered. Formation of distal arterial pulse wave is represented as a composition of forward and reflected pulse waves propagating along the arterial vessels. The formal analogy between pulse waves propagation along the human arterial system and the propagation of electrical oscillations in electrical transmission lines with distributed parameters was proposed. Dependencies of pulse wave propagation along the human arterial system were obtained by solving the one-dimensional Navier-Stokes equations for a few special cases.

Higher dimensional curved domain walls on Kähler surfaces

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

Akbar, Fiki T., E-mail: ftakbar@fi.itb.ac.id; Gunara, Bobby E., E-mail: bobby@fi.itb.ac.id; Radjabaycolle, Flinn C.

In this paper we study some aspects of curved BPS-like domain walls in higher dimensional gravity theory coupled to scalars where the scalars span a complex Kähler surface with scalar potential turned on. Assuming that a fake superpotential has a special form which depends on Kähler potential and a holomorphic function, we prove that BPS-like equations have a local unique solution. Then, we analyze the vacuum structure of the theory including their stability using dynamical system and their existence in ultraviolet-infrared regions using renormalization group flow.

Omnidirectional-view three-dimensional display system based on cylindrical selective-diffusing screen.

PubMed

Xia, Xinxing; Zheng, Zhenrong; Liu, Xu; Li, Haifeng; Yan, Caijie

2010-09-10

We utilized a high-frame-rate projector, a rotating mirror, and a cylindrical selective-diffusing screen to present a novel three-dimensional (3D) omnidirectional-view display system without the need for any special viewing aids. The display principle and image size are analyzed, and the common display zone is proposed. The viewing zone for one observation place is also studied. The experimental results verify this method, and a vivid color 3D scene with occlusion and smooth parallax is also demonstrated with the system.

Perfect absorption of modified-molybdenum-disulfide-based Tamm plasmonic structures

NASA Astrophysics Data System (ADS)

Wang, Xiaoyu; Wang, Jicheng; Hu, Zheng-Da; Sang, Tian; Feng, Yan

2018-06-01

The two-dimensional semiconductor materials of transition metal molybdenum disulfide display various special optical properties in the interaction of matter and light. In this work, we study the strong coupling between the two-dimensional materials’ excitons and Tamm plasmon polaritons (TPPs). To enhance the interaction between light and matter, we introduce the grating modulation in the traditional Tamm structure. By adjusting the structure parameters of the grating-modified Tamm system, we achieve perfect absorption in the visible region. Our research results will pave the way for the application of ultrathin polarization optical devices.

Finite-Element Analysis of Residual Stresses Generated Under Nitriding Process: a Three-Dimensional Model

NASA Astrophysics Data System (ADS)

Sawicki, J.; Siedlaczek, P.; Staszczyk, A.

2018-03-01

A numerical three-dimensional model for computing residual stresses generated in cross section of steel 42CrMo4 after nitriding is presented. The diffusion process is analyzed by the finite-element method. The internal stresses are computed using the obtained profile of the distribution of the nitrogen concentration. The special features of the intricate geometry of the treated articles including edges and angles are considered. Comparative analysis of the results of the simulation and of the experimental measurement of residual stresses is performed by the Waisman-Philips method.

Three-dimensional multifunctional optical coherence tomography for skin imaging

NASA Astrophysics Data System (ADS)

Li, En; Makita, Shuichi; Hong, Young-Joo; Kasaragod, Deepa; Sasaoka, Tomoko; Yamanari, Masahiro; Sugiyama, Satoshi; Yasuno, Yoshiaki

2016-02-01

Optical coherence tomography (OCT) visualizes cross-sectional microstructures of biological tissues. Recent developments of multifunctional OCT (MF-OCT) provides multiple optical contrasts which can reveal currently unknown tissue properties. In this contribution we demonstrate multifunctional OCT specially designed for dermatological investigation. And by utilizing it to measure four different body parts of in vivo human skin, three-dimensional scattering OCT, OCT angiography, polarization uniformity tomography, and local birefringence tomography images were obtained by a single scan. They respectively contrast the structure and morphology, vasculature, melanin content and collagen traits of the tissue.

Sports-specialized intensive training and the risk of injury in young athletes: a clinical case-control study.

PubMed

Jayanthi, Neeru A; LaBella, Cynthia R; Fischer, Daniel; Pasulka, Jacqueline; Dugas, Lara R

2015-04-01

Data are lacking regarding the independent risk of injury related to intense single-sport training or growth rate in young athletes. To determine whether sports specialization, weekly training volumes, and growth rates are associated with increased risk for injury and serious overuse injury in young athletes. Case-control study; Level of evidence, 3. Injured athletes aged 7 to 18 years were recruited from 2 hospital-based sports medicine clinics and compared with healthy controls from affiliated primary care clinics undergoing sports physicals (2010-2013). Participants completed surveys reporting hours per week spent in organized sports, physical education class, and free play, as well as degree of sports specialization and Tanner stage. Heights and weights were measured. Injury details were obtained from athlete surveys and electronic medical records. Of 1214 athletes enrolled, 1190 (50.7% male) had data satisfactory for analysis. There were 822 injured participants (49.5% male; unique injuries, n = 846) and 368 uninjured participants (55% male). Injured athletes were older than uninjured athletes (14.1 ± 2.1 vs. 12.9 ± 2.6 years; P < .001) and reported more total hours of physical activity (19.6 ± 9.2 vs. 17.6 ± 8.9 h/wk; P < .001) and organized sports activity (11.2 ± 2.6 vs. 9.1 ± 6.3 h/wk; P < .01). After accounting for age and hours in sports activity spent per week, sports-specialized training was an independent risk for injury (odds ratio [OR], 1.27; 95% CI, 1.07-1.52; P < .01) and serious overuse injury (OR, 1.36; 95% CI, 1.08-1.72; P < .01). Young athletes participating in more hours of sports per week than number of age in years (OR, 2.07; 95% CI, 1.40-3.05; P < .001) or whose ratio of organized sports to free play time was >2:1 hours/week had increased odds of having a serious overuse injury (OR, 1.87; 95% CI, 1.26-2.76; P < .01). Growth rates were similar between injured and uninjured athletes (4.8 cm/y for both groups; P = .96). Injured young athletes were older and spent more hours per week in organized sports. There is an independent risk of injury and serious overuse injury in young athletes who specialize in a single sport. Growth rate was not related to injury risk. The study data provide guidance for clinicians counseling young athletes and their parents regarding injury risks associated with sports specialization. © 2015 The Author(s).

Electrons in Flatland

NASA Astrophysics Data System (ADS)

MacDonald, Allan

2007-04-01

Like the classical squares and triangles in Edwin Abbott's 19th century social satire and science fiction novel Flatland, electrons and other quantum particles behave differently when confined to a two-dimensional world. Condensed matter physicists have been intrigued and regularly suprised by two-dimensional electron systems since they were first studied in semiconductor field-effect-transistor devices over forty years ago. I will discuss some important milestones in the study of two-dimensional electrn systems, from the discoveries of the integer and fractional quantum Hall effects in the 1980's to recent quantum Hall effect work on quasiparticles with non-Abelian quantum statistics. Special attention will be given to a new electronic Flatland that has risen to prominence recently, graphene, which consists of a single sheet of carbon atoms in a honeycomb lattice arrangement. Graphene provides a realization of two-dimensional massless Dirac fermions which interact via nearly instantaneous Coulomb interactions. Early research on graphene has demonstrated yet again that Flatland exceeds expectations.

Three-dimensional portable document format: a simple way to present 3-dimensional data in an electronic publication.

PubMed

Danz, Jan C; Katsaros, Christos

2011-08-01

Three-dimensional (3D) models of teeth and soft and hard tissues are tessellated surfaces used for diagnosis, treatment planning, appliance fabrication, outcome evaluation, and research. In scientific publications or communications with colleagues, these 3D data are often reduced to 2-dimensional pictures or need special software for visualization. The portable document format (PDF) offers a simple way to interactively display 3D surface data without additional software other than a recent version of Adobe Reader (Adobe, San Jose, Calif). The purposes of this article were to give an example of how 3D data and their analyses can be interactively displayed in 3 dimensions in electronic publications, and to show how they can be exported from any software for diagnostic reports and communications among colleagues. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Phonon thermal conduction in novel 2D materials.

PubMed

Xu, Xiangfan; Chen, Jie; Li, Baowen

2016-12-07

Recently, there has been increasing interest in phonon thermal transport in low-dimensional materials, due to the crucial importance of dissipating and managing heat in micro- and nano-electronic devices. Significant progress has been achieved for one-dimensional (1D) systems, both theoretically and experimentally. However, the study of heat conduction in two-dimensional (2D) systems is still in its infancy due to the limited availability of 2D materials and the technical challenges of fabricating suspended samples that are suitable for thermal measurements. In this review, we outline different experimental techniques and theoretical approaches for phonon thermal transport in 2D materials, discuss the problems and challenges of phonon thermal transport measurements and provide a comparison between existing experimental data. Special attention will be given to the effects of size, dimensionality, anisotropy and mode contributions in novel 2D systems, including graphene, boron nitride, MoS 2 , black phosphorous and silicene.

Photogrammetry of the three-dimensional shape and texture of a nanoscale particle using scanning electron microscopy and free software.

PubMed

Gontard, Lionel C; Schierholz, Roland; Yu, Shicheng; Cintas, Jesús; Dunin-Borkowski, Rafal E

2016-10-01

We apply photogrammetry in a scanning electron microscope (SEM) to study the three-dimensional shape and surface texture of a nanoscale LiTi2(PO4)3 particle. We highlight the fact that the technique can be applied non-invasively in any SEM using free software (freeware) and does not require special sample preparation. Three-dimensional information is obtained in the form of a surface mesh, with the texture of the sample stored as a separate two-dimensional image (referred to as a UV Map). The mesh can be used to measure parameters such as surface area, volume, moment of inertia and center of mass, while the UV map can be used to study the surface texture using conventional image processing techniques. We also illustrate the use of 3D printing to visualize the reconstructed model. Copyright © 2016 Elsevier B.V. All rights reserved.

Development of a system for acquiring, reconstructing, and visualizing three-dimensional ultrasonic angiograms

NASA Astrophysics Data System (ADS)

Edwards, Warren S.; Ritchie, Cameron J.; Kim, Yongmin; Mack, Laurence A.

1995-04-01

We have developed a three-dimensional (3D) imaging system using power Doppler (PD) ultrasound (US). This system can be used for visualizing and analyzing the vascular anatomy of parenchymal organs. To create the 3D PD images, we acquired a series of two-dimensional PD images from a commercial US scanner and recorded the position and orientation of each image using a 3D magnetic position sensor. Three-dimensional volumes were reconstructed using specially designed software and then volume rendered for display. We assessed the feasibility and geometric accuracy of our system with various flow phantoms. The system was then tested on a volunteer by scanning a transplanted kidney. The reconstructed volumes of the flow phantom contained less than 1 mm of geometric distortion and the 3D images of the transplanted kidney depicted the segmental, arcuate, and interlobar vessels.

Fermionic currents in AdS spacetime with compact dimensions

NASA Astrophysics Data System (ADS)

Bellucci, S.; Saharian, A. A.; Vardanyan, V.

2017-09-01

We derive a closed expression for the vacuum expectation value (VEV) of the fermionic current density in a (D +1 )-dimensional locally AdS spacetime with an arbitrary number of toroidally compactified Poincaré spatial dimensions and in the presence of a constant gauge field. The latter can be formally interpreted in terms of a magnetic flux treading the compact dimensions. In the compact subspace, the field operator obeys quasiperiodicity conditions with arbitrary phases. The VEV of the charge density is zero and the current density has nonzero components along the compact dimensions only. They are periodic functions of the magnetic flux with the period equal to the flux quantum and tend to zero on the AdS boundary. Near the horizon, the effect of the background gravitational field is small and the leading term in the corresponding asymptotic expansion coincides with the VEV for a massless field in the locally Minkowski bulk. Unlike the Minkowskian case, in the system consisting of an equal number of fermionic and scalar degrees of freedom, with same masses, charges and phases in the periodicity conditions, the total current density does not vanish. In these systems, the leading divergences in the scalar and fermionic contributions on the horizon are canceled and, as a consequence of that, the charge flux, integrated over the coordinate perpendicular to the AdS boundary, becomes finite. We show that in odd spacetime dimensions the fermionic fields realizing two inequivalent representations of the Clifford algebra and having equal phases in the periodicity conditions give the same contribution to the VEV of the current density. Combining the contributions from these fields, the current density in odd-dimensional C -,P - and T -symmetric models are obtained. As an application, we consider the ground state current density in curved carbon nanotubes described in terms of a (2 +1 )-dimensional effective Dirac model.

Two-dimensional topological photonics

NASA Astrophysics Data System (ADS)

Khanikaev, Alexander B.; Shvets, Gennady

2017-12-01

Originating from the studies of two-dimensional condensed-matter states, the concept of topological order has recently been expanded to other fields of physics and engineering, particularly optics and photonics. Topological photonic structures have already overturned some of the traditional views on wave propagation and manipulation. The application of topological concepts to guided wave propagation has enabled novel photonic devices, such as reflection-free sharply bent waveguides, robust delay lines, spin-polarized switches and non-reciprocal devices. Discrete degrees of freedom, widely used in condensed-matter physics, such as spin and valley, are now entering the realm of photonics. In this Review, we summarize the latest advances in this highly dynamic field, with special emphasis on the experimental work on two-dimensional photonic topological structures.

The possibility of using photogrammetric and remote sensing techniques to model lavaka (gully erosion) development in Madagascar

NASA Astrophysics Data System (ADS)

Raveloson, Andrea; Székely, Balázs; Molnár, Gábor; Rasztovits, Sascha

2013-04-01

Gully erosion is a worldwide problem for it has a number of undesirable effects and their development is hard to follow. Madagascar is one of the most affected countries for its highlands are densely covered with gullies named lavakas. Lavaka formation and development seems to be triggered by many regional and local causes but the actual reasons are still poorly understood. Furthermore lavakas differ from normal gullies due to their enormous size and special shape. Field surveys are time consuming and data from two-dimensional measurements and pictures (even aerial) might lack major information for morphologic studies. Therefore close range surveying technologies should be used to get three-dimensional information about these unusual and complex features. This contribution discusses which remote sensing and photogrammetric techniques are adequate to survey the development of lavakas, their volume change and sediment budget. Depending on the types and properties (such as volume, depth, shape, vegetation) of the lavaka different methods will be proposed showing pros and cons of each one of them. Our goal is to review techniques to model, survey and analyze lavakas development to better understand the cause of their formation, special size and shape. Different methods are evaluated and compared from field survey through data processing, analyzing cost-effectiveness, potential errors and accuracy for each one of them. For this purpose we will also consider time- and cost-effectiveness of the softwares able to render the images into 3D model as well as the resolution and accuracy of the outputs. Further studies will concentrate on using the three dimensional models of lavakas which will be later on used for geomorphological studies in order to understand their special shape and size. This is ILARG-contribution #07.

Racial health disparities among special health care needs children with mental disorders: do medical homes cater to their needs?

PubMed

Park, Chanhyun; Tan, Xi; Patel, Isha B; Reiff, Amanda; Balkrishnan, Rajesh; Chang, Jongwha

2014-10-01

A health care reform has been taking place to provide cost-effective and coordinated care. One method of achieving these goals is a patient-centered medical home (PCMH) model, which is associated with provision of quality care among children belonging to racial/ethnic minorities. Despite the potential of the PCMH for children of minority backgrounds, little is known about the extent to which minorities with mental disorders have the PCMH. The study examined racial/ethnic disparities among children with mental disorders in accessing care from the PCMH. The 2009-2010 National Survey of Children with Special Health Care Needs (CSHCN) was used for this analysis. Multivariate logistic regressions were applied to capture the racial/ethnic disparities and to analyze a composite outcome of the PCMH. An estimated population size of 4 677 904 CSHCN with mental disorders was included. Among them, 59.94% of children reported to have received medical homes. Compared with white children, the odds of receiving any medical home services decreased among Hispanic children (odds ratio [OR] = 0.69; P < .05) and black children (OR = 0.70; P < .05). The likelihood of having a medical home was lower for Hispanic children than white children, when they had attention deficit hyperactivity disorder (ADHD; OR = 0.57; P < .05) and development delay (OR = 0.73; P < .05). Compared with white children with ADHD or depression having a medical home, the odds of black children with ADHD (OR = 0.63; P < .05) and depression (OR = 0.68; P < .05) having a medical home were lower. There were significant racial/ethnic disparities among CSHCN with mental disorders, indicating several sizeable effects of each of the 5 components on Hispanic, black, and other children compared with white children. These differences could be a potential to improve racial/ethnic disparities. © The Author(s) 2014.

An Interior Signage System for the USAF Academy Hospital

DTIC Science & Technology

1979-08-01

manner. Graphic Design - Graphic design is a design for visual communication . Graphic Design Tools - There are four basic graphic design tools available...specializes in the design of two dimensional visual communication components. The graphic designer utilizes the four graphic design tools in developing

Product competitiveness analysis for e-commerce platform of special agricultural products

NASA Astrophysics Data System (ADS)

Wan, Fucheng; Ma, Ning; Yang, Dongwei; Xiong, Zhangyuan

2017-09-01

On the basis of analyzing the influence factors of the product competitiveness of the e-commerce platform of the special agricultural products and the characteristics of the analytical methods for the competitiveness of the special agricultural products, the price, the sales volume, the postage included service, the store reputation, the popularity, etc. were selected in this paper as the dimensionality for analyzing the competitiveness of the agricultural products, and the principal component factor analysis was taken as the competitiveness analysis method. Specifically, the web crawler was adopted to capture the information of various special agricultural products in the e-commerce platform ---- chi.taobao.com. Then, the original data captured thereby were preprocessed and MYSQL database was adopted to establish the information library for the special agricultural products. Then, the principal component factor analysis method was adopted to establish the analysis model for the competitiveness of the special agricultural products, and SPSS was adopted in the principal component factor analysis process to obtain the competitiveness evaluation factor system (support degree factor, price factor, service factor and evaluation factor) of the special agricultural products. Then, the linear regression method was adopted to establish the competitiveness index equation of the special agricultural products for estimating the competitiveness of the special agricultural products.

Identifying the genes of unconventional high temperature superconductors.

PubMed

Hu, Jiangping

We elucidate a recently emergent framework in unifying the two families of high temperature (high [Formula: see text]) superconductors, cuprates and iron-based superconductors. The unification suggests that the latter is simply the counterpart of the former to realize robust extended s-wave pairing symmetries in a square lattice. The unification identifies that the key ingredients (gene) of high [Formula: see text] superconductors is a quasi two dimensional electronic environment in which the d -orbitals of cations that participate in strong in-plane couplings to the p -orbitals of anions are isolated near Fermi energy. With this gene, the superexchange magnetic interactions mediated by anions could maximize their contributions to superconductivity. Creating the gene requires special arrangements between local electronic structures and crystal lattice structures. The speciality explains why high [Formula: see text] superconductors are so rare. An explicit prediction is made to realize high [Formula: see text] superconductivity in Co/Ni-based materials with a quasi two dimensional hexagonal lattice structure formed by trigonal bipyramidal complexes.

Global analysis of an impulsive delayed Lotka-Volterra competition system

NASA Astrophysics Data System (ADS)

Xia, Yonghui

2011-03-01

In this paper, a retarded impulsive n-species Lotka-Volterra competition system with feedback controls is studied. Some sufficient conditions are obtained to guarantee the global exponential stability and global asymptotic stability of a unique equilibrium for such a high-dimensional biological system. The problem considered in this paper is in many aspects more general and incorporates as special cases various problems which have been extensively studied in the literature. Moreover, applying the obtained results to some special cases, I derive some new criteria which generalize and greatly improve some well known results. A method is proposed to investigate biological systems subjected to the effect of both impulses and delays. The method is based on Banach fixed point theory and matrix's spectral theory as well as Lyapunov function. Moreover, some novel analytic techniques are employed to study GAS and GES. It is believed that the method can be extended to other high-dimensional biological systems and complex neural networks. Finally, two examples show the feasibility of the results.

Flow field predictions for a slab delta wing at incidence

NASA Technical Reports Server (NTRS)

Conti, R. J.; Thomas, P. D.; Chou, Y. S.

1972-01-01

Theoretical results are presented for the structure of the hypersonic flow field of a blunt slab delta wing at moderately high angle of attack. Special attention is devoted to the interaction between the boundary layer and the inviscid entropy layer. The results are compared with experimental data. The three-dimensional inviscid flow is computed numerically by a marching finite difference method. Attention is concentrated on the windward side of the delta wing, where detailed comparisons are made with the data for shock shape and surface pressure distributions. Surface streamlines are generated, and used in the boundary layer analysis. The three-dimensional laminar boundary layer is computed numerically using a specially-developed technique based on small cross-flow in streamline coordinates. In the rear sections of the wing the boundary layer decreases drastically in the spanwise direction, so that it is still submerged in the entropy layer at the centerline, but surpasses it near the leading edge. Predicted heat transfer distributions are compared with experimental data.

Automated method for structural segmentation of nasal airways based on cone beam computed tomography

NASA Astrophysics Data System (ADS)

Tymkovych, Maksym Yu.; Avrunin, Oleg G.; Paliy, Victor G.; Filzow, Maksim; Gryshkov, Oleksandr; Glasmacher, Birgit; Omiotek, Zbigniew; DzierŻak, RóŻa; Smailova, Saule; Kozbekova, Ainur

2017-08-01

The work is dedicated to the segmentation problem of human nasal airways using Cone Beam Computed Tomography. During research, we propose a specialized approach of structured segmentation of nasal airways. That approach use spatial information, symmetrisation of the structures. The proposed stages can be used for construction a virtual three dimensional model of nasal airways and for production full-scale personalized atlases. During research we build the virtual model of nasal airways, which can be used for construction specialized medical atlases and aerodynamics researches.

Alternative method for evaluating the pair energy of nucleons in nuclei

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

Nurmukhamedov, A. M., E-mail: fattah52@mail.ru

2015-12-15

An alternative method for determining the odd–even effect parameter related to special features of the Casimir operator in Wigner’s mass formula for nuclei is proposed. A procedure for calculating this parameter is presented. The proposed method relies on a geometric interpretation of the Casimir operator, experimental data concerning the contribution of spin–orbit interaction to the nuclear mass for even–even and odd–odd nuclei, and systematics of energy gaps in the spectra of excited states of even–even nuclei.

Unconventional Restraint: Obstacles to Army Special Operations Forces Employment in Support to Resistance Operations

DTIC Science & Technology

2017-12-01

resistance potential42 exists, and the odds of success are only improved when an external power provides support, it may be logical to assume that...the reality that some efforts will, and have failed . As the empirical evidence shows, when the U.S. government supports resistance movements short...and soft power . When civil protests turned to civil war in Syria and the survival of the Assad regime came into question, the Iranians quickly came to

Optimization of parameters of special asynchronous electric drives

NASA Astrophysics Data System (ADS)

Karandey, V. Yu; Popov, B. K.; Popova, O. B.; Afanasyev, V. L.

2018-03-01

The article considers the solution of the problem of parameters optimization of special asynchronous electric drives. The solution of the problem will allow one to project and create special asynchronous electric drives for various industries. The created types of electric drives will have optimum mass-dimensional and power parameters. It will allow one to realize and fulfill the set characteristics of management of technological processes with optimum level of expenses of electric energy, time of completing the process or other set parameters. The received decision allows one not only to solve a certain optimizing problem, but also to construct dependences between the optimized parameters of special asynchronous electric drives, for example, with the change of power, current in a winding of the stator or rotor, induction in a gap or steel of magnetic conductors and other parameters. On the constructed dependences, it is possible to choose necessary optimum values of parameters of special asynchronous electric drives and their components without carrying out repeated calculations.

Chow groups of intersections of quadrics via homological projective duality and (Jacobians of) non-commutative motives

NASA Astrophysics Data System (ADS)

Bernardara, M.; Tabuada, G.

2016-06-01

Conjectures of Beilinson-Bloch type predict that the low-degree rational Chow groups of intersections of quadrics are one-dimensional. This conjecture was proved by Otwinowska in [20]. By making use of homological projective duality and the recent theory of (Jacobians of) non-commutative motives, we give an alternative proof of this conjecture in the case of a complete intersection of either two quadrics or three odd-dimensional quadrics. Moreover, we prove that in these cases the unique non-trivial algebraic Jacobian is the middle one. As an application, we make use of Vial's work [26], [27] to describe the rational Chow motives of these complete intersections and show that smooth fibrations into such complete intersections over bases S of small dimension satisfy Murre's conjecture (when \\dim (S)≤ 1), Grothendieck's standard conjecture of Lefschetz type (when \\dim (S)≤ 2), and Hodge's conjecture (when \\dim(S)≤ 3).

Fuzzyics =CATEGORYICS =PRAGMATYICS (``Son of ``TRIZ''')/CATEGORY-SEMANTICS Cognition (fcp/csc) of Plato-Aristotle ``SQUARE-of-OPPOSITION''(SoO): Linguistics: Antonyms VS ``SYNONYMS'' VS Analogy/ Metaphor: Coarsest-Possible Topology: Shocks/High-Pressures Applications

NASA Astrophysics Data System (ADS)

Siegel, Edward Plato Aristotle Archimedes Carl-Ludwig; Young, Frederic; Lewis, Thomas

2013-06-01

Siegel[MRS Fall-Mtgs,:Symp.Fractals(89)-5-papers!!!;Symp.Scaling(90)] FCP/CSC {aka SPD}(Tic-Tac-Toe-Matrix/Tabular List-Format) ``COMMON-FUNCTIONING-PRINCIPLE'' DI/TRI-CHOTOMY GENERIC ``INEVITABILITY_-WEB'' PURPOSEFUL PARSIMONY-of-DI/TRI-CHOTOMY STRATEGY REdiscovery of SoO automatically/optimality is in NON-list-format/matrix: DIMENSIONALITY-DOMINATION -INEVIT-ABILITY ROOT-CAUSE(RC) ULTIMATE-ORIGIN(UO): (level-0.-logic) DIMENSIONALITY (level-0. logic): [dst = ODD-Z] <->{Dst=FRACTAL-UNcertainty FLUCTUATIONS} <->(dst = EVEN-Z): CAUSES: (level- I.-logic): EXTENT/SCALE/RADIUS: (relative)-[LOCALITY] <-> (relative)-(...GLOBALITY...) & (level-II.-logic): POWER-SPECTRUM{noise ≅generalized-susceptibility}: [``l''/ω0-White] <->(...-``l''/ω 1 . 000 . . . - HYPERBOLICITY...) & (level-III.-logic) CRITICAL-EXPONENT:n =0 <->n = 1.000... ; BUT ALL 3 ALSO CAUSED BY ANOTHER INdependent RCUO (level-IV.-logic):

Thermally and electrically controllable multiple high harmonics generation by harmonically driven quasi-two-dimensional electron gas

NASA Astrophysics Data System (ADS)

Maglevanny, I. I.; Smolar, V. A.; Karyakina, T. I.

2018-06-01

In this paper, we consider the activation processes in nonlinear meta-stable system based on a lateral (quasi-two-dimensional) superlattice and study the dynamics of such a system externally driven by a harmonic force. The internal control parameters are the longitudinal applied electric field and the sample temperature. The spontaneous transverse electric field is considered as an order parameter. The forced violations of order parameter are considered as a response of a system to periodic driving. We investigate the cooperative effects of self-organization and high harmonic forcing from the viewpoint of catastrophe theory and show the possibility of generation of third and higher odd harmonics in output signal that lead to distortion of its wave front. A higher harmonics detection strategy is further proposed and explained in detail by exploring the influences of system parameters on the response output of the system that are discussed through numerical simulations.

Boundary conformal anomalies on hyperbolic spaces and Euclidean balls

NASA Astrophysics Data System (ADS)

Rodriguez-Gomez, Diego; Russo, Jorge G.

2017-12-01

We compute conformal anomalies for conformal field theories with free conformal scalars and massless spin 1/2 fields in hyperbolic space ℍ d and in the ball B^d , for 2≤d≤7. These spaces are related by a conformal transformation. In even dimensional spaces, the conformal anomalies on ℍ2 n and B^{2n} are shown to be identical. In odd dimensional spaces, the conformal anomaly on B^{2n+1} comes from a boundary contribution, which exactly coincides with that of ℍ2 n + 1 provided one identifies the UV short-distance cutoff on B^{2n+1} with the inverse large distance IR cutoff on ℍ2 n + 1, just as prescribed by the conformal map. As an application, we determine, for the first time, the conformal anomaly coefficients multiplying the Euler characteristic of the boundary for scalars and half-spin fields with various boundary conditions in d = 5 and d = 7.

Topological phases in frustrated synthetic ladders with an odd number of legs

NASA Astrophysics Data System (ADS)

Barbarino, Simone; Dalmonte, Marcello; Fazio, Rosario; Santoro, Giuseppe E.

2018-01-01

The realization of the Hofstadter model in a strongly anisotropic ladder geometry has now become possible in one-dimensional optical lattices with a synthetic dimension. In this work, we show how the Hofstadter Hamiltonian in such ladder configurations hosts a topological phase of matter which is radically different from its two-dimensional counterpart. This topological phase stems directly from the hybrid nature of the ladder geometry and is protected by a properly defined inversion symmetry. We start our analysis by considering the paradigmatic case of a three-leg ladder which supports a topological phase exhibiting the typical features of topological states in one dimension: robust fermionic edge modes, a degenerate entanglement spectrum, and a nonzero Zak phase; then, we generalize our findings—addressable in the state-of-the-art cold-atom experiments—to ladders with a higher number of legs.

Three-dimensional fractional-spin gravity

NASA Astrophysics Data System (ADS)

Boulanger, Nicolas; Sundell, Per; Valenzuela, Mauricio

2014-02-01

Using Wigner-deformed Heisenberg oscillators, we construct 3D Chern-Simons models consisting of fractional-spin fields coupled to higher-spin gravity and internal nonabelian gauge fields. The gauge algebras consist of Lorentz-tensorial Blencowe-Vasiliev higher-spin algebras and compact internal algebras intertwined by infinite-dimensional generators in lowest-weight representations of the Lorentz algebra with fractional spin. In integer or half-integer non-unitary cases, there exist truncations to gl(ℓ , ℓ ± 1) or gl(ℓ|ℓ ± 1) models. In all non-unitary cases, the internal gauge fields can be set to zero. At the semi-classical level, the fractional-spin fields are either Grassmann even or odd. The action requires the enveloping-algebra representation of the deformed oscillators, while their Fock-space representation suffices on-shell. The project was funded in part by F.R.S.-FNRS " Ulysse" Incentive Grant for Mobility in Scientific Research.

Two-dimensional models as testing ground for principles and concepts of local quantum physics

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

Schroer, Bert

In the past two-dimensional models of QFT have served as theoretical laboratories for testing new concepts under mathematically controllable condition. In more recent times low-dimensional models (e.g., chiral models, factorizing models) often have been treated by special recipes in a way which sometimes led to a loss of unity of QFT. In the present work, I try to counteract this apartheid tendency by reviewing past results within the setting of the general principles of QFT. To this I add two new ideas: (1) a modular interpretation of the chiral model Diff(S)-covariance with a close connection to the recently formulated localmore » covariance principle for QFT in curved spacetime and (2) a derivation of the chiral model temperature duality from a suitable operator formulation of the angular Wick rotation (in analogy to the Nelson-Symanzik duality in the Ostertwalder-Schrader setting) for rational chiral theories. The SL (2, Z) modular Verlinde relation is a special case of this thermal duality and (within the family of rational models) the matrix S appearing in the thermal duality relation becomes identified with the statistics character matrix S. The relevant angular 'Euclideanization' is done in the setting of the Tomita-Takesaki modular formalism of operator algebras. I find it appropriate to dedicate this work to the memory of J.A. Swieca with whom I shared the interest in two-dimensional models as a testing ground for QFT for more than one decade. This is a significantly extended version of an 'Encyclopedia of Mathematical Physics' contribution hep-th/0502125.« less

Two-dimensional models as testing ground for principles and concepts of local quantum physics

NASA Astrophysics Data System (ADS)

Schroer, Bert

2006-02-01

In the past two-dimensional models of QFT have served as theoretical laboratories for testing new concepts under mathematically controllable condition. In more recent times low-dimensional models (e.g., chiral models, factorizing models) often have been treated by special recipes in a way which sometimes led to a loss of unity of QFT. In the present work, I try to counteract this apartheid tendency by reviewing past results within the setting of the general principles of QFT. To this I add two new ideas: (1) a modular interpretation of the chiral model Diff( S)-covariance with a close connection to the recently formulated local covariance principle for QFT in curved spacetime and (2) a derivation of the chiral model temperature duality from a suitable operator formulation of the angular Wick rotation (in analogy to the Nelson-Symanzik duality in the Ostertwalder-Schrader setting) for rational chiral theories. The SL (2, Z) modular Verlinde relation is a special case of this thermal duality and (within the family of rational models) the matrix S appearing in the thermal duality relation becomes identified with the statistics character matrix S. The relevant angular "Euclideanization" is done in the setting of the Tomita-Takesaki modular formalism of operator algebras. I find it appropriate to dedicate this work to the memory of J.A. Swieca with whom I shared the interest in two-dimensional models as a testing ground for QFT for more than one decade. This is a significantly extended version of an "Encyclopedia of Mathematical Physics" contribution hep-th/0502125.

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

Kim, A.; Avakian, H.; Burkert, V.

The target and double spin asymmetries of the exclusive pseudoscalar channel e→p→→epπ0 were measured for the first time in the deep-inelastic regime using a longitudinally polarized 5.9 GeV electron beam and a longitudinally polarized proton target at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS). The data were collected over a large kinematic phase space and divided into 110 four-dimensional bins of Q2, xB, -t and Φ. Large values of asymmetry moments clearly indicate a substantial contribution to the polarized structure functions from transverse virtual photon amplitudes. The interpretation of experimental data in terms of generalized parton distributions (GPDs)more » provides the first insight on the chiral-odd GPDs H˜T and ET, and complement previous measurements of unpolarized structure functions sensitive to the GPDs HT and E¯T. These data provide a crucial input for parametrizations of essentially unknown chiral-odd GPDs and will strongly influence existing theoretical calculations based on the handbag formalism.« less

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

Kim, A.; Avakian, H.; Burkert, V.

The target and double spin asymmetries of the exclusive pseudoscalar channelmore » $$\\vec e\\vec p\\to ep\\pi^0$$ were measured for the first time in the deep-inelastic regime using a longitudinally polarized 5.9 GeV electron beam and a longitudinally polarized proton target at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS). The data were collected over a large kinematic phase space and divided into 110 four-dimensional bins of $Q^2$, $$x_B$$, $-t$ and $$\\phi$$. Large values of asymmetry moments clearly indicate a substantial contribution to the polarized structure functions from transverse virtual photon amplitudes. The interpretation of experimental data in terms of generalized parton distributions (GPDs) provides the first insight on the chiral-odd GPDs $$\\tilde{H}_T$$ and $$E_T$$, and complement previous measurements of unpolarized structure functions sensitive to the GPDs $$H_T$$ and $$\\bar E_T$$. Finally, these data provide necessary constraints for chiral-odd GPD parametrizations and will strongly influence existing theoretical handbag models.« less

Gaussian processes with built-in dimensionality reduction: Applications to high-dimensional uncertainty propagation

NASA Astrophysics Data System (ADS)

Tripathy, Rohit; Bilionis, Ilias; Gonzalez, Marcial

2016-09-01

Uncertainty quantification (UQ) tasks, such as model calibration, uncertainty propagation, and optimization under uncertainty, typically require several thousand evaluations of the underlying computer codes. To cope with the cost of simulations, one replaces the real response surface with a cheap surrogate based, e.g., on polynomial chaos expansions, neural networks, support vector machines, or Gaussian processes (GP). However, the number of simulations required to learn a generic multivariate response grows exponentially as the input dimension increases. This curse of dimensionality can only be addressed, if the response exhibits some special structure that can be discovered and exploited. A wide range of physical responses exhibit a special structure known as an active subspace (AS). An AS is a linear manifold of the stochastic space characterized by maximal response variation. The idea is that one should first identify this low dimensional manifold, project the high-dimensional input onto it, and then link the projection to the output. If the dimensionality of the AS is low enough, then learning the link function is a much easier problem than the original problem of learning a high-dimensional function. The classic approach to discovering the AS requires gradient information, a fact that severely limits its applicability. Furthermore, and partly because of its reliance to gradients, it is not able to handle noisy observations. The latter is an essential trait if one wants to be able to propagate uncertainty through stochastic simulators, e.g., through molecular dynamics codes. In this work, we develop a probabilistic version of AS which is gradient-free and robust to observational noise. Our approach relies on a novel Gaussian process regression with built-in dimensionality reduction. In particular, the AS is represented as an orthogonal projection matrix that serves as yet another covariance function hyper-parameter to be estimated from the data. To train the model, we design a two-step maximum likelihood optimization procedure that ensures the orthogonality of the projection matrix by exploiting recent results on the Stiefel manifold, i.e., the manifold of matrices with orthogonal columns. The additional benefit of our probabilistic formulation, is that it allows us to select the dimensionality of the AS via the Bayesian information criterion. We validate our approach by showing that it can discover the right AS in synthetic examples without gradient information using both noiseless and noisy observations. We demonstrate that our method is able to discover the same AS as the classical approach in a challenging one-hundred-dimensional problem involving an elliptic stochastic partial differential equation with random conductivity. Finally, we use our approach to study the effect of geometric and material uncertainties in the propagation of solitary waves in a one dimensional granular system.

Gaussian processes with built-in dimensionality reduction: Applications to high-dimensional uncertainty propagation

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

Tripathy, Rohit, E-mail: rtripath@purdue.edu; Bilionis, Ilias, E-mail: ibilion@purdue.edu; Gonzalez, Marcial, E-mail: marcial-gonzalez@purdue.edu

2016-09-15

Uncertainty quantification (UQ) tasks, such as model calibration, uncertainty propagation, and optimization under uncertainty, typically require several thousand evaluations of the underlying computer codes. To cope with the cost of simulations, one replaces the real response surface with a cheap surrogate based, e.g., on polynomial chaos expansions, neural networks, support vector machines, or Gaussian processes (GP). However, the number of simulations required to learn a generic multivariate response grows exponentially as the input dimension increases. This curse of dimensionality can only be addressed, if the response exhibits some special structure that can be discovered and exploited. A wide range ofmore » physical responses exhibit a special structure known as an active subspace (AS). An AS is a linear manifold of the stochastic space characterized by maximal response variation. The idea is that one should first identify this low dimensional manifold, project the high-dimensional input onto it, and then link the projection to the output. If the dimensionality of the AS is low enough, then learning the link function is a much easier problem than the original problem of learning a high-dimensional function. The classic approach to discovering the AS requires gradient information, a fact that severely limits its applicability. Furthermore, and partly because of its reliance to gradients, it is not able to handle noisy observations. The latter is an essential trait if one wants to be able to propagate uncertainty through stochastic simulators, e.g., through molecular dynamics codes. In this work, we develop a probabilistic version of AS which is gradient-free and robust to observational noise. Our approach relies on a novel Gaussian process regression with built-in dimensionality reduction. In particular, the AS is represented as an orthogonal projection matrix that serves as yet another covariance function hyper-parameter to be estimated from the data. To train the model, we design a two-step maximum likelihood optimization procedure that ensures the orthogonality of the projection matrix by exploiting recent results on the Stiefel manifold, i.e., the manifold of matrices with orthogonal columns. The additional benefit of our probabilistic formulation, is that it allows us to select the dimensionality of the AS via the Bayesian information criterion. We validate our approach by showing that it can discover the right AS in synthetic examples without gradient information using both noiseless and noisy observations. We demonstrate that our method is able to discover the same AS as the classical approach in a challenging one-hundred-dimensional problem involving an elliptic stochastic partial differential equation with random conductivity. Finally, we use our approach to study the effect of geometric and material uncertainties in the propagation of solitary waves in a one dimensional granular system.« less

Body mass index of adults with intellectual disability participating in Special Olympics by world region.

PubMed

Temple, V A; Foley, J T; Lloyd, M

2014-03-01

People with intellectual disability (ID) experience poorer health and have more unmet health needs compared with people without ID, and they are often absent from population health surveillance. The aim of this study was to describe the body mass index (BMI) status of adult Special Olympics participants by world region and gender. Additionally, the general influence of age and gender on overweight/obesity of all participants was explored. A total of 11 643 (7150 male and 4493 female) Special Olympics BMI records were available from the Special Olympics International Health Promotion database. BMI was compared by gender and world region. Logistic regression was used to examine whether age and gender were associated with the likelihood of being overweight/obese (BMI ≥ 25.0). Overall, 5.5% of the sample was underweight, 36.1% in the normal range, 24.7% overweight and 32.1% obese, and levels of overweight/obesity were very high in North America. Both age and gender were significant predictors of overweight/obesity (odds ratios 1.06 and 0.59, respectively). Our findings demonstrate that adult Special Olympics participants have high levels of overweight and obesity; particularly among women and those from North America. It is crucial that those who work with, care for, coach and live with adults with ID who participate in Special Olympics increase efforts to promote healthy weight status. © 2013 The Authors. Journal of Intellectual Disability Research © 2013 John Wiley & Sons Ltd, MENCAP & IASSIDD.

Atrial Septal Aneurysm and Patent Foramen Ovale as Risk Factors for Cryptogenic Stroke in Patients Less Than 55 Years of Age: A Study using Transesophageal Echocardiography

NASA Technical Reports Server (NTRS)

Cabanes, L.; Mas, J. L.; Cohen, A.; Amarenco, P.; Cabanes, P. A.; Oubary, P.; Chedru, F.; Guerin, F.; Bousser, M. G.; deRecondo, J.

1993-01-01

Background and Purpose: An association between atrial septal aneurysm and embolic events has been suggested. Atrial septal aneurysm has been shown to be associated with patent foramen ovale and,.in some reports, with mitral valve prolapse. These two latter cardiac disorder; have been identified as potential risk factors for ischemic stroke. The aim of this prospective study was to assess the role of atrial septal aneurysm as an independent risk factor for stroke, especially for cryptogenic stroke. Methods: We studied the prevalence of atrial septal aneurysm, patent foramen ovale, and mitral valve prolapse in 100 consecutive patients <55 years of age with ischemic stroke who underwent extensive etiological investigations. We compared these results with those in a control group of 50 consecutive patients. The diagnosis of atrial septal aneurysm and patent foramen ovale relied on transesophageal echocardiography with a contrast study and that of mitral valve prolapse, on two-dimensional transthoracic echocardiography. Results: Stepwise logistic regression analysis showed that atrial septal aneurysm (odds ratio, 4.3; 95% confidence interval, 1.3 to 14.6; P=.01) and patent foramen ovale (odds ratio, 3.9; 95% confidence interval, 1.5 to 10; P=.003) but not mitral valve prolapse were significantly associated with the diagnosis of cryptogenic stroke. The stroke odds of a patient with both atrial septal aneurysm and patent foramen ovale were 33.3 times (95% confidence interval, 4.1 to 270) the stroke odds of a patient with neither of these cardiac disorders. For a patient with atrial septal aneurysm of >lo-mm excursion, the stroke odds were approximately 8 times the stroke odds of a patient with atrial septal aneurysm of <10 mm. Conclusions: This study shows that atrial septal aneurysm and patent foramen ovale are both significantly associated with cryptogenic stroke and that their association has a marked synergistic effect. Atrial septal aneurysms of >lo-mm excursion are associated with a higher risk of stroke. (Stroke. 1993;24:1865-1873.) KEY WORDS aneurysm echocardiography foramen ovale, patent mitral valve prolapse o young adults

Bound states in the continuum on periodic structures surrounded by strong resonances

NASA Astrophysics Data System (ADS)

Yuan, Lijun; Lu, Ya Yan

2018-04-01

Bound states in the continuum (BICs) are trapped or guided modes with their frequencies in the frequency intervals of the radiation modes. On periodic structures, a BIC is surrounded by a family of resonant modes with their quality factors approaching infinity. Typically the quality factors are proportional to 1 /|β - β*|2 , where β and β* are the Bloch wave vectors of the resonant modes and the BIC, respectively. But for some special BICs, the quality factors are proportional to 1 /|β - β*|4 . In this paper, a general condition is derived for such special BICs on two-dimensional periodic structures. As a numerical example, we use the general condition to calculate special BICs, which are antisymmetric standing waves, on a periodic array of circular cylinders, and show their dependence on parameters. The special BICs are important for practical applications, because they produce resonances with large quality factors for a very large range of β .

Data Transformation in a Three Dimensional Integrated Circuit Implementation

DTIC Science & Technology

2012-03-01

the difficult moments. My special thank to my wife Vanessa , who is always beside me with her endless love. Your support and motivation were... Van Oorschot and S. A. Vanstone. Handbook of Applied Cryptograpy, 1997. [19] L. C. Washington and W. Trappe, Introduction to Cryptography: With

Multi-Dimensional, Inviscid Flux Reconstruction for Simulation of Hypersonic Heating on Tetrahedral Grids

NASA Technical Reports Server (NTRS)

Gnoffo, Peter A.

2009-01-01

The quality of simulated hypersonic stagnation region heating on tetrahedral meshes is investigated by using a three-dimensional, upwind reconstruction algorithm for the inviscid flux vector. Two test problems are investigated: hypersonic flow over a three-dimensional cylinder with special attention to the uniformity of the solution in the spanwise direction and hypersonic flow over a three-dimensional sphere. The tetrahedral cells used in the simulation are derived from a structured grid where cell faces are bisected across the diagonal resulting in a consistent pattern of diagonals running in a biased direction across the otherwise symmetric domain. This grid is known to accentuate problems in both shock capturing and stagnation region heating encountered with conventional, quasi-one-dimensional inviscid flux reconstruction algorithms. Therefore the test problem provides a sensitive test for algorithmic effects on heating. This investigation is believed to be unique in its focus on three-dimensional, rotated upwind schemes for the simulation of hypersonic heating on tetrahedral grids. This study attempts to fill the void left by the inability of conventional (quasi-one-dimensional) approaches to accurately simulate heating in a tetrahedral grid system. Results show significant improvement in spanwise uniformity of heating with some penalty of ringing at the captured shock. Issues with accuracy near the peak shear location are identified and require further study.

Universal measurement-based quantum computation in two-dimensional symmetry-protected topological phases

NASA Astrophysics Data System (ADS)

Wei, Tzu-Chieh; Huang, Ching-Yu

2017-09-01

Recent progress in the characterization of gapped quantum phases has also triggered the search for a universal resource for quantum computation in symmetric gapped phases. Prior works in one dimension suggest that it is a feature more common than previously thought, in that nontrivial one-dimensional symmetry-protected topological (SPT) phases provide quantum computational power characterized by the algebraic structure defining these phases. Progress in two and higher dimensions so far has been limited to special fixed points. Here we provide two families of two-dimensional Z2 symmetric wave functions such that there exists a finite region of the parameter in the SPT phases that supports universal quantum computation. The quantum computational power appears to lose its universality at the boundary between the SPT and the symmetry-breaking phases.

Toward two-dimensional search engines

NASA Astrophysics Data System (ADS)

Ermann, L.; Chepelianskii, A. D.; Shepelyansky, D. L.

2012-07-01

We study the statistical properties of various directed networks using ranking of their nodes based on the dominant vectors of the Google matrix known as PageRank and CheiRank. On average PageRank orders nodes proportionally to a number of ingoing links, while CheiRank orders nodes proportionally to a number of outgoing links. In this way, the ranking of nodes becomes two dimensional which paves the way for the development of two-dimensional search engines of a new type. Statistical properties of information flow on the PageRank-CheiRank plane are analyzed for networks of British, French and Italian universities, Wikipedia, Linux Kernel, gene regulation and other networks. A special emphasis is done for British universities networks using the large database publicly available in the UK. Methods of spam links control are also analyzed.

Suicide Risk and Resiliency Factors Among Hispanic Teens in New Mexico: Schools Can Make a Difference.

PubMed

Hall, Meryn; Fullerton, Lynne; FitzGerald, Courtney; Green, Dan

2018-03-01

Youth suicide is a serious public health problem in the United States. School environments, and the attention of school adults, are promising but minimally studied avenues for promoting mental health among students. The 2013 New Mexico Youth Risk and Resiliency Survey data were analyzed to identify ways in which the school environment influences suicide attempts in a sample of Hispanic students. Factors examined were: relationships with school adults, speaking a language other than English at home, being born outside the United States and not having enough to eat. Odds ratios were used to measure relationships. Factors influencing suicide attempt were similar for boys and girls. The odds of suicide attempt declined by approximately one third as measures of positive relationships with school adults increased. Post-high school education plans also were protective. Being born outside the United States and not having enough to eat increased the odds of past-year suicide attempt. Speaking a language other than English at home was a weak risk factor for suicide attempt only among Hispanic girls. Teachers and other school adults can decrease suicide risk for Hispanic teens by forming supportive relationships with students. Special consideration should be given to providing free breakfast in schools. © 2018, American School Health Association.

Dynamics of cosmic strings with higher-dimensional windings

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

Yamauchi, Daisuke; Lake, Matthew J.; Thailand Center of Excellence in Physics, Ministry of Education,Bangkok 10400

2015-06-11

We consider F-strings with arbitrary configurations in the Minkowski directions of a higher-dimensional spacetime, which also wrap and spin around S{sup 1} subcycles of constant radius in an arbitrary internal manifold, and determine the relation between the higher-dimensional and the effective four-dimensional quantities that govern the string dynamics. We show that, for any such configuration, the motion of the windings in the compact space may render the string effectively tensionless from a four-dimensional perspective, so that it remains static with respect to the large dimensions. Such a critical configuration occurs when (locally) exactly half the square of the string lengthmore » lies in the large dimensions and half lies in the compact space. The critical solution is then seen to arise as a special case, in which the wavelength of the windings is equal to their circumference. As examples, long straight strings and circular loops are considered in detail, and the solutions to the equations of motion that satisfy the tensionless condition are presented. These solutions are then generalized to planar loops and arbitrary three-dimensional configurations. Under the process of dimensional reduction, in which higher-dimensional motion is equivalent to an effective worldsheet current (giving rise to a conserved charge), this phenomenon may be seen as the analogue of the tensionless condition which arises for superconducting and chiral-current carrying cosmic strings.« less

Dynamics of cosmic strings with higher-dimensional windings

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

Yamauchi, Daisuke; Lake, Matthew J., E-mail: yamauchi@resceu.s.u-tokyo.ac.jp, E-mail: matthewj@nu.ac.th

2015-06-01

We consider F-strings with arbitrary configurations in the Minkowski directions of a higher-dimensional spacetime, which also wrap and spin around S{sup 1} subcycles of constant radius in an arbitrary internal manifold, and determine the relation between the higher-dimensional and the effective four-dimensional quantities that govern the string dynamics. We show that, for any such configuration, the motion of the windings in the compact space may render the string effectively tensionless from a four-dimensional perspective, so that it remains static with respect to the large dimensions. Such a critical configuration occurs when (locally) exactly half the square of the string lengthmore » lies in the large dimensions and half lies in the compact space. The critical solution is then seen to arise as a special case, in which the wavelength of the windings is equal to their circumference. As examples, long straight strings and circular loops are considered in detail, and the solutions to the equations of motion that satisfy the tensionless condition are presented. These solutions are then generalized to planar loops and arbitrary three-dimensional configurations. Under the process of dimensional reduction, in which higher-dimensional motion is equivalent to an effective worldsheet current (giving rise to a conserved charge), this phenomenon may be seen as the analogue of the tensionless condition which arises for superconducting and chiral-current carrying cosmic strings.« less

Generalized moments expansion applied to the two-dimensional S= 1 /2 Heisenberg model

NASA Astrophysics Data System (ADS)

Mancini, Jay D.; Murawski, Robert K.; Fessatidis, Vassilios; Bowen, Samuel P.

2005-12-01

In this work we derive a generalized moments expansion (GMX), to third order, of which the well-established connected moments expansion and the alternate moments expansion are shown to be special cases. We discuss the benefits of the GMX with respect to the avoidance of singularities which are known to plague such moments methods. We then apply the GMX estimates for the ground-state energy for the two-dimensional S=1/2 Heisenberg square lattice and compare these results to those of both spin-wave theory and the linked-cluster expansion.

Exact traveling-wave and spatiotemporal soliton solutions to the generalized (3+1)-dimensional Schrödinger equation with polynomial nonlinearity of arbitrary order.

PubMed

Petrović, Nikola Z; Belić, Milivoj; Zhong, Wei-Ping

2011-02-01

We obtain exact traveling wave and spatiotemporal soliton solutions to the generalized (3+1)-dimensional nonlinear Schrödinger equation with variable coefficients and polynomial Kerr nonlinearity of an arbitrarily high order. Exact solutions, given in terms of Jacobi elliptic functions, are presented for the special cases of cubic-quintic and septic models. We demonstrate that the widely used method for finding exact solutions in terms of Jacobi elliptic functions is not applicable to the nonlinear Schrödinger equation with saturable nonlinearity. ©2011 American Physical Society

Phase Transitions in a Model of Y-Molecules Abstract

NASA Astrophysics Data System (ADS)

Holz, Danielle; Ruth, Donovan; Toral, Raul; Gunton, James

Immunoglobulin is a Y-shaped molecule that functions as an antibody to neutralize pathogens. In special cases where there is a high concentration of immunoglobulin molecules, self-aggregation can occur and the molecules undergo phase transitions. This prevents the molecules from completing their function. We used a simplified model of 2-Dimensional Y-molecules with three identical arms on a triangular lattice with 2-dimensional Grand Canonical Ensemble. The molecules were permitted to be placed, removed, rotated or moved on the lattice. Once phase coexistence was found, we used histogram reweighting and multicanonical sampling to calculate our phase diagram.

The D-dimensional non-relativistic particle in the Scarf Trigonometry plus Non-Central Rosen-Morse Potentials

NASA Astrophysics Data System (ADS)

Deta, U. A.; Lestari, N. A.; Yantidewi, M.; Suparmi, A.; Cari, C.

2018-03-01

The D-Dimensional Non-Relativistic Particle Properties in the Scarf Trigonometry plus Non-Central Rosen-Morse Potentials was investigated using an analytical method. The bound state energy is given approximately in the closed form. The approximate wave function for arbitrary l-state in D-dimensions are expressed in the form of generalised Jacobi Polynomials. The energy spectra of the particle are increased when the dimensions are higher. The relationship between the orbital number in each dimension is recursive. The special case in 3 dimensions is given to the ground state.

Analysis of physical-chemical processes governing SSME internal fluid flows

NASA Technical Reports Server (NTRS)

Singhal, A. K.; Owens, S. F.; Mukerjee, T.; Keeton, L. W.; Prakash, C.; Przekwas, A. J.

1984-01-01

The efforts to adapt CHAM's computational fluid dynamics code, PHOENICS, to the analysis of flow within the high pressure fuel turbopump (HPFTP) aft-platform seal cavity of the SSME are summarized. In particular, the special purpose PHOENICS satellite and ground station specifically formulated for this application are listed and described, and the preliminary results of the first part two-dimensional analyses are presented and discussed. Planned three-dimensional analyses are also briefly outlined. To further understand the mixing and combustion processes in the SSME fuelside preburners, a single oxygen-hydrogen jet element was investigated.

Probing quantum gravity through exactly soluble midi-superspaces I

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

Ashtekar, A.; Pierri, M.

1996-12-01

It is well-known that the Einstein-Rosen solutions to the 3+1- dimensional vacuum Einstein{close_quote}s equations are in one to one correspondence with solutions of 2+1-dimensional general relativity coupled to axi-symmetric, zero rest mass scalar fields. We first re-examine the quantization of this midi-superspace paying special attention to the asymptotically flat boundary conditions and to certain functional analytic subtleties associated with regularization. We then use the resulting quantum theory to analyze several conceptual and technical issues of quantum gravity. {copyright} {ital 1996 American Institute of Physics.}

All ASD complex and real 4-dimensional Einstein spaces with Λ≠0 admitting a nonnull Killing vector

NASA Astrophysics Data System (ADS)

Chudecki, Adam

2016-12-01

Anti-self-dual (ASD) 4-dimensional complex Einstein spaces with nonzero cosmological constant Λ equipped with a nonnull Killing vector are considered. It is shown that any conformally nonflat metric of such spaces can be always brought to a special form and the Einstein field equations can be reduced to the Boyer-Finley-Plebański equation (Toda field equation). Some alternative forms of the metric are discussed. All possible real slices (neutral, Euclidean and Lorentzian) of ASD complex Einstein spaces with Λ≠0 admitting a nonnull Killing vector are found.

A possible generalization of the harmonic oscillator potential

NASA Technical Reports Server (NTRS)

Levai, Geza

1995-01-01

A four-parameter potential is analyzed, which contains the three-dimensional harmonic oscillator as a special case. This potential is exactly solvable and retains several characteristics of the harmonic oscillator, and also of the Coulomb problem. The possibility of similar generalizations of other potentials is also pointed out.

Partial regularity of viscosity solutions for a class of Kolmogorov equations arising from mathematical finance

NASA Astrophysics Data System (ADS)

Rosestolato, M.; Święch, A.

2017-02-01

We study value functions which are viscosity solutions of certain Kolmogorov equations. Using PDE techniques we prove that they are C 1 + α regular on special finite dimensional subspaces. The problem has origins in hedging derivatives of risky assets in mathematical finance.

Probability Distributions of Minkowski Distances between Discrete Random Variables.

ERIC Educational Resources Information Center

Schroger, Erich; And Others

1993-01-01

Minkowski distances are used to indicate similarity of two vectors in an N-dimensional space. How to compute the probability function, the expectation, and the variance for Minkowski distances and the special cases City-block distance and Euclidean distance. Critical values for tests of significance are presented in tables. (SLD)

Nilpotent representations of classical quantum groups at roots of unity

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

Abe, Yuuki; Nakashima, Toshiki

2005-11-01

Properly specializing the parameters in 'Schnizer modules', for types A,B,C, and D, we get its unique primitive vector. Then we show that the module generated by the primitive vector is an irreducible highest weight module of finite dimensional classical quantum groups at roots of unity.

Virtual Environments and Autism: A Developmental Psychopathological Approach

ERIC Educational Resources Information Center

Rajendran, G.

2013-01-01

Individuals with autism spectrum disorders supposedly have an affinity with information and communication technology (ICT), making it an ideally suited media for this population. Virtual environments (VEs)--both two-dimensional and immersive--represent a particular kind of ICT that might be of special benefit. Specifically, this paper discusses…

Celebratory Cakes

ERIC Educational Resources Information Center

Mahoney, Ellen

2012-01-01

Cakes are no longer the simple desserts they once were. The cake has evolved into an elaborate, sculptural form that represents a special occasion. Sculptural cake forms have become expressive designs using three-dimensional shapes, an array of surface textures, and a range of colors. The use of cakes in the artwork of David Gilhooly, Wayne…

Phase transitions and magnetization of the mixed-spin Ising–Heisenberg double sawtooth frustrated ladder

NASA Astrophysics Data System (ADS)

Arian Zad, Hamid; Ananikian, Nerses

2018-04-01

The mixed spin-(1,1/2) Ising–Heisenberg double sawtooth ladder containing a mixture of both spin-1 and spin-1/2 nodal atoms, and the spin-1/2 interstitial dimers are approximately solved by the transfer-matrix method. Here, we study in detail the ground-state phase diagrams, also influences of the bilinear exchange coupling on the rungs and cyclic four-spin exchange interaction in square plaquette of each block on the magnetization and magnetic susceptibility of the suggested ladder at low temperature. Such a double sawtooth ladder may be found in a Shastry-Sutherland lattice-type. In spite of the spin ordering of odd and even blocks being different from each other, due to the commutation relation between all different block Hamiltonians, phase diagrams, magnetization behavior and thermodynamic properties of the model are the same for odd and even blocks. We show that at low temperature, both exchange couplings can change the quality and quantity of the magnetization plateaus versus the magnetic field changes. Specially, we find a new magnetization plateau M/Ms= 5/6 for this model. Besides, we examine the magnetic susceptibility and specific heat of the model in detail. It is proven that behaviors of the magnetization and the magnetic susceptibility coincide at low temperature. The specific heat displays diverse temperature dependencies, which include a Schottky-type peak at a special temperature interval. We observe that with increase of the bilinear exchange coupling on the rungs, second peak temperature dependence grows.

Comprehensive smoke-free policies: a tool for improving preconception health?

PubMed

Klein, Elizabeth G; Liu, Sherry T; Conrey, Elizabeth J

2014-01-01

Lower income women are at higher risk for preconception and prenatal smoking, are less likely to spontaneously quit smoking during pregnancy, and have higher prenatal relapse rates than women in higher income groups. Policies prohibiting tobacco smoking in public places are intended to reduce exposure to secondhand smoke; additionally, since these policies promote a smoke-free norm, there have been associations between smoke-free policies and reduced smoking prevalence. Given the public health burden of smoking, particularly among women who become pregnant, our objective was to assess the impact of smoke-free policies on the odds of preconception smoking among low-income women. We estimated the odds of preconception smoking among low-income women in Ohio between 2002 and 2009 using data from repeated cross-sectional samples of women participating in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). A logistic spline regression was applied fitting a knot at the point of enforcement of the Ohio Smoke-free Workplace Act to evaluate whether this policy was associated with changes in the odds of smoking. After adjusting for individual- and environmental-level factors, the Ohio Smoke-free Workplace Act was associated with a small, but statistically significant reduction in the odds of preconception smoking in WIC participants. Comprehensive smoke-free policies prohibiting smoking in public places and workplaces may also be associated with reductions in smoking among low-income women. This type of policy or environmental change strategy may promote a tobacco-free norm and improve preconception health among a population at risk for smoking.

A Study of the Unstable Modes in High Mach Number Gaseous Jets and Shear Layers

NASA Astrophysics Data System (ADS)

Bassett, Gene Marcel

1993-01-01

Instabilities affecting the propagation of supersonic gaseous jets have been studied using high resolution computer simulations with the Piecewise-Parabolic-Method (PPM). These results are discussed in relation to jets from galactic nuclei. These studies involve a detailed treatment of a single section of a very long jet, approximating the dynamics by using periodic boundary conditions. Shear layer simulations have explored the effects of shear layers on the growth of nonlinear instabilities. Convergence of the numerical approximations has been tested by comparing jet simulations with different grid resolutions. The effects of initial conditions and geometry on the dominant disruptive instabilities have also been explored. Simulations of shear layers with a variety of thicknesses, Mach numbers and densities perturbed by incident sound waves imply that the time for the excited kink modes to grow large in amplitude and disrupt the shear layer is taug = (546 +/- 24) (M/4)^{1.7 } (Apert/0.02) ^{-0.4} delta/c, where M is the jet Mach number, delta is the half-width of the shear layer, and A_ {pert} is the perturbation amplitude. For simulations of periodic jets, the initial velocity perturbations set up zig-zag shock patterns inside the jet. In each case a single zig-zag shock pattern (an odd mode) or a double zig-zag shock pattern (an even mode) grows to dominate the flow. The dominant kink instability responsible for these shock patterns moves approximately at the linear resonance velocity, nu_ {mode} = cextnu_ {relative}/(cjet + c_ {ext}). For high resolution simulations (those with 150 or more computational zones across the jet width), the even mode dominates if the even penetration is higher in amplitude initially than the odd perturbation. For low resolution simulations, the odd mode dominates even for a stronger even mode perturbation. In high resolution simulations the jet boundary rolls up and large amounts of external gas are entrained into the jet. In low resolution simulations this entrainment process is impeded by numerical viscosity. The three-dimensional jet simulations behave similarly to two-dimensional jet runs with the same grid resolutions.

Casual Set Approach to a Minimal Invariant Length

NASA Astrophysics Data System (ADS)

Raut, Usha

2007-04-01

Any attempt to quantize gravity would necessarily introduce a minimal observable length scale of the order of the Planck length. This conclusion is based on several different studies and thought experiments and appears to be an inescapable feature of all quantum gravity theories, irrespective of the method used to quantize gravity. Over the last few years there has been growing concern that such a minimal length might lead to a contradiction with the basic postulates of special relativity, in particular the Lorentz-Fitzgerald contraction. A few years ago, Rovelli et.al, attempted to reconcile an invariant minimal length with Special Relativity, using the framework of loop quantum gravity. However, the inherently canonical formalism of the loop quantum approach is plagued by a variety of problems, many brought on by separation of space and time co-ordinates. In this paper we use a completely different approach. Using the framework of the causal set paradigm, along with a statistical measure of closeness between Lorentzian manifolds, we re-examine the issue of introducing a minimal observable length that is not at odds with Special Relativity postulates.

Hierarchical and non-hierarchical {lambda} elements for one dimensional problems with unknown strength of singularity

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

Wong, K.K.; Surana, K.S.

1996-10-01

This paper presents a new and general procedure for designing hierarchical and non-hierarchical special elements called {lambda} elements for one dimensional singular problems where the strength of the singularity is unknown. The {lambda} element formulations presented here permit correct numerical simulation of linear as well as non-linear singular problems without a priori knowledge of the strength of the singularity. A procedure is also presented for determining the exact strength of the singularity using the converged solution. It is shown that in special instances, the general formulation of {lambda} elements can also be made hierarchical. The {lambda} elements presented here aremore » of type C{sup 0} and provide C{sup 0} inter-element continuity with p-version elements. One dimensional steady state radial flow of an upper convected Maxwell fluid is considered as a sample problem. Since in this case {lambda}{sub i} are known, this problem provides a good example for investigating the performance of the formulation proposed here. Least squares approach (or Least Squares Finite Element Formulation: LSFEF) is used to construct the integral form (error functional I) from the differential equations. Numerical studies are presented for radially inward flow of an upper convected Maxwell fluid with inner radius r{sub i} = .1 and .01 etc. and Deborah number De = 2.« less

The Work Ability Index as a screening tool to identify the need for rehabilitation: longitudinal findings from the Second German Sociomedical Panel of Employees.

PubMed

Bethge, Matthias; Radoschewski, Friedrich Michael; Gutenbrunner, Christoph

2012-11-01

To evaluate the predictive value of the Work Ability Index (WAI) for different indicators of the need for rehabilitation at 1-year follow-up. Cohort study. Data were obtained from the Second German Sociomedical Panel of Employees, a large-scale cohort study with postal surveys in 2009 and 2010. A total of 457 women and 579 men were included. Confirmatory factor analysis confirmed the one-dimensionality of the WAI. Regression analyses showed that poor and moderate baseline WAI scores were associated with lower health-related quality of life and more frequent use of primary healthcare 1 year later. Subjects with poor baseline work ability had 4.6 times higher odds of unemployment and 12.2 times higher odds of prolonged sick leave than the reference group with good or excellent baseline work ability. Moreover, the odds of subjectively perceived need for rehabilitation, intention to request rehabilitation and actual use of rehabilitation services were 9.7, 5.7 and 3 times higher in the poor baseline WAI group and 5.5, 4 and 1.8 times higher in the moderate baseline WAI group, respectively. A WAI score ≤ 37 was identified as the optimal cut-off to predict the need for rehabilitation. The WAI is a valid screening tool for identifying the need for rehabilitation.

A Novel Approach to Prediction of Mild Obstructive Sleep Disordered Breathing in a Population-Based Sample: The Sleep Heart Health Study

PubMed Central

Caffo, Brian; Diener-West, Marie; Punjabi, Naresh M.; Samet, Jonathan

2010-01-01

This manuscript considers a data-mining approach for the prediction of mild obstructive sleep disordered breathing, defined as an elevated respiratory disturbance index (RDI), in 5,530 participants in a community-based study, the Sleep Heart Health Study. The prediction algorithm was built using modern ensemble learning algorithms, boosting in specific, which allowed for assessing potential high-dimensional interactions between predictor variables or classifiers. To evaluate the performance of the algorithm, the data were split into training and validation sets for varying thresholds for predicting the probability of a high RDI (≥ 7 events per hour in the given results). Based on a moderate classification threshold from the boosting algorithm, the estimated post-test odds of a high RDI were 2.20 times higher than the pre-test odds given a positive test, while the corresponding post-test odds were decreased by 52% given a negative test (sensitivity and specificity of 0.66 and 0.70, respectively). In rank order, the following variables had the largest impact on prediction performance: neck circumference, body mass index, age, snoring frequency, waist circumference, and snoring loudness. Citation: Caffo B; Diener-West M; Punjabi NM; Samet J. A novel approach to prediction of mild obstructive sleep disordered breathing in a population-based sample: the Sleep Heart Health Study. SLEEP 2010;33(12):1641-1648. PMID:21120126

String-inspired special grand unification

NASA Astrophysics Data System (ADS)

Yamatsu, Naoki

2017-10-01

We discuss a grand unified theory (GUT) based on an SO(32) GUT gauge group broken to its subgroups including a special subgroup. In the SO(32) GUT on the six-dimensional (6D) orbifold space M^4× T^2/\\mathbb{Z}_2, one generation of the standard model fermions can be embedded into a 6D bulk Weyl fermion in the SO(32) vector representation. We show that for a three-generation model, all the 6D and 4D gauge anomalies in the bulk and on the fixed points are canceled out without exotic chiral fermions at low energies.

Combustion theory for liquids with a free surface. 3: Special problems

NASA Technical Reports Server (NTRS)

Milkov, S. N.; Sukhov, G. S.; Yarin, L. P.

1986-01-01

Two special problems concerning the combustion of liquids with a free surface, i.e., flame quenching during the mixing of a burning liquid inside a container and liquid burnout from a porous layer, are analyzed using a quasi-one-dimensional model. The critical parameters corresponding to the quenching of a burning fluid with a free surface are determined. Determinations are also made of the limiting pressure gradients corresponding to the transition from the combustion mode where the liquid evaporates from the surface of a porous layer to the mode where the phase transition surface lies inside the porous layer.

Exact solution of matricial Φ23 quantum field theory

NASA Astrophysics Data System (ADS)

Grosse, Harald; Sako, Akifumi; Wulkenhaar, Raimar

2017-12-01

We apply a recently developed method to exactly solve the Φ3 matrix model with covariance of a two-dimensional theory, also known as regularised Kontsevich model. Its correlation functions collectively describe graphs on a multi-punctured 2-sphere. We show how Ward-Takahashi identities and Schwinger-Dyson equations lead in a special large- N limit to integral equations that we solve exactly for all correlation functions. The solved model arises from noncommutative field theory in a special limit of strong deformation parameter. The limit defines ordinary 2D Schwinger functions which, however, do not satisfy reflection positivity.

Dental care utilization and expenditures in children with special health care needs.

PubMed

Beil, Heather; Mayer, Michelle; Rozier, R Gary

2009-09-01

The authors compared children with special health care needs (CSHCN) and children without special health care needs (SHCN) with respect to the odds, amount and determinants of having any dental care and dental care expenditures. The authors assessed data from the 2004 Medical Expenditures Panel Survey, Agency for Healthcare Research and Quality, to identify a sample of 8,518 children aged 2 to 17 years. The authors used logistic regression to determine the effect of having SHCN on the probability of having any dental care expenditure, for total dental care expenditures and procedure-specific expenditures. They tested the modifying effect between CSHCN and other variables on the probability of having any dental care expenditure. Compared with children without SHCN, CSHCN did not differ in the probability (odds ratio = 0.91, 95 percent confidence interval [CI] = 0.76 to 1.09) or amount (beta = 30.17, 95 percent CI = -162.93 to 223.27) of total dental care expenditures. Likewise, CSHCN did not differ in their likelihood of having undergone a preventive, restorative, diagnostic or other procedure. Known determinants of dental care utilization did not modify the relationships between having SCHN and any dental care expenditure. Despite the reported difficulty in CSHCN's accessing dental care, the authors found that CSHCN had dental care utilization and expenditures that were comparable with those of children without SHCN. Furthermore, the association of CSHCN status and any dental care expenditure was not modified by known determinants of dental care utilization. Future research should focus on characterizing risk for dental disease among CSHCN more accurately and identifying factors that affect dental care utilization in CSHCN, including provider and parent characteristics. The study results highlight low rates of dental care utilization among all young children, including CSHCN. Efforts to increase dental care utilization among children are warranted and need to include broad-based provider and parent initiatives.

Trends in Unmet Need for Genetic Counseling Among Children With Special Health Care Needs, 2001-2010.

PubMed

Smith, Anna Jo; Oswald, Donald; Bodurtha, Joann

2015-01-01

Access to genetic counseling is increasingly important to guide families' and clinicians' decision making, yet there is limited research on accessibility and affordability of counseling for families with children with special health care needs (CSHCN). Our study's objectives were to measure changes in unmet need for genetic counseling for CSHCN from 2001 to 2010 and to characterize child, family, and health system factors associated with unmet need. We used parent-reported data from the 2001, 2005-2006, and 2009-2010 National Survey of Children With Special Health Care Needs. We used a logistic regression model to measure the impact of survey year, child (sex, age, severity of health condition), family (primary language, household income, insurance, financial problems related to cost of CSHCN's health care), and health system factors (region, genetic counselors per capita, having a usual source of care) on access to genetic counseling. Unmet need for genetic counseling increased significantly in 2009-2010 compared to 2001 (odds ratio 1.89; 95% confidence interval [CI] 1.44-2.47). Being older (adjusted odds ratio [aOR] 1.04; 95% CI 1.02-1.06), having severe health limitations (aOR 1.72; 95% CI 1.16-2.58), being uninsured (aOR 3.56; 95% CI 2.16-5.87), and having family financial problems due to health care costs (aOR 1.90; 95% CI 1.52-2.38) were significantly associated with greater unmet need for genetic counseling. Having a usual source of care was associated with decreased unmet need (aOR 0.55; 95% CI 0.37-0.83). Unmet need for genetic counseling has increased over the past 12 years. Uninsurance and financial problems related to health care costs were the largest drivers of unmet need over time. Copyright © 2015 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

The transformation of targeted killing and international order.

PubMed

Senn, Martin; Troy, Jodok

2017-05-04

This article introduces the special issue's question of whether and how the current transformation of targeted killing is transforming the global international order and provides the conceptual ground for the individual contributions to the special issue. It develops a two-dimensional concept of political order and introduces a theoretical framework that conceives the maintenance and transformation of international order as a dynamic interplay between its behavioral dimension in the form of violence and discursive processes and its institutional dimension in the form of ideas, norms, and rules. The article also conceptualizes targeted killing and introduces a typology of targeted-killing acts on the basis of their legal and moral legitimacy. Building on this conceptual groundwork, the article takes stock of the current transformation of targeted killing and summarizes the individual contributions to this special issue.

Three-dimensional laser window formation for industrial application

NASA Technical Reports Server (NTRS)

Verhoff, Vincent G.; Kowalski, David

1993-01-01

The NASA Lewis Research Center has developed and implemented a unique process for forming flawless three-dimensional, compound-curvature laser windows to extreme accuracies. These windows represent an integral component of specialized nonintrusive laser data acquisition systems that are used in a variety of compressor and turbine research testing facilities. These windows are molded to the flow surface profile of turbine and compressor casings and are required to withstand extremely high pressures and temperatures. This method of glass formation could also be used to form compound-curvature mirrors that would require little polishing and for a variety of industrial applications, including research view ports for testing devices and view ports for factory machines with compound-curvature casings. Currently, sodium-alumino-silicate glass is recommended for three-dimensional laser windows because of its high strength due to chemical strengthening and its optical clarity. This paper discusses the main aspects of three-dimensional laser window formation. It focuses on the unique methodology and the peculiarities that are associated with the formation of these windows.

Characterization of the dimensional stability of advanced metallic materials using an optical test bench structure

NASA Technical Reports Server (NTRS)

Hsieh, Cheng; O'Donnell, Timothy P.

1991-01-01

The dimensional stability of low-density high specific-strength metal-matrix composites (including 30 vol pct SiC(p)/SXA 24-T6 Al, 25 vol pct SiC(p)/6061-T6 Al, 40 vol pct graphite P100 fiber/6061 Al, 50 vol pct graphite P100 fiber/6061 Al, and 40 vol pct P100 graphite fiber/AZ91D Mg composites) and an Al-Li-Mg metal alloy was evaluated using a specially designed five-strut optical test bench structure. The structure had 30 thermocouple locations, one retroreflector, one linear interferometer multilayer insulation, and various strip heaters. It was placed in a 10 exp -7 torr capability vacuum chamber with a laser head positioned at a window port, and a laser interferometer system for collecting dimensional change data. It was found that composite materials have greater 40-C temporal dimensional stability than the AL-Li-Mg alloy. Aluminum-based composites demonstrated better 40-C temporal stability than Mg-based composites.

A Two-Dimensional Linear Bicharacteristic Scheme for Electromagnetics

NASA Technical Reports Server (NTRS)

Beggs, John H.

2002-01-01

The upwind leapfrog or Linear Bicharacteristic Scheme (LBS) has previously been implemented and demonstrated on one-dimensional electromagnetic wave propagation problems. This memorandum extends the Linear Bicharacteristic Scheme for computational electromagnetics to model lossy dielectric and magnetic materials and perfect electrical conductors in two dimensions. This is accomplished by proper implementation of the LBS for homogeneous lossy dielectric and magnetic media and for perfect electrical conductors. Both the Transverse Electric and Transverse Magnetic polarizations are considered. Computational requirements and a Fourier analysis are also discussed. Heterogeneous media are modeled through implementation of surface boundary conditions and no special extrapolations or interpolations at dielectric material boundaries are required. Results are presented for two-dimensional model problems on uniform grids, and the Finite Difference Time Domain (FDTD) algorithm is chosen as a convenient reference algorithm for comparison. The results demonstrate that the two-dimensional explicit LBS is a dissipation-free, second-order accurate algorithm which uses a smaller stencil than the FDTD algorithm, yet it has less phase velocity error.

E(lementary)-strings in six-dimensional heterotic F-theory

NASA Astrophysics Data System (ADS)

Choi, Kang-Sin; Rey, Soo-Jong

2017-09-01

Using E-strings, we can analyze not only six-dimensional superconformal field theories but also probe vacua of non-perturabative heterotic string. We study strings made of D3-branes wrapped on various two-cycles in the global F-theory setup. We claim that E-strings are elementary in the sense that various combinations of E-strings can form M-strings as well as heterotic strings and new kind of strings, called G-strings. Using them, we show that emissions and combinations of heterotic small instantons generate most of known six-dimensional superconformal theories, their affinizations and little string theories. Taking account of global structure of compact internal geometry, we also show that special combinations of E-strings play an important role in constructing six-dimensional theories of D- and E-types. We check global consistency conditions from anomaly cancellation conditions, both from five-branes and strings, and show that they are given in terms of elementary E-string combinations.

Opportunity Landing Spot Panorama (3-D Model)

NASA Technical Reports Server (NTRS)

2004-01-01

The rocky outcrop traversed by the Mars Exploration Rover Opportunity is visible in this three-dimensional model of the rover's landing site. Opportunity has acquired close-up images along the way, and scientists are using the rover's instruments to closely examine portions of interest. The white fragments that look crumpled near the center of the image are portions of the airbags. Distant scenery is displayed on a spherical backdrop or 'billboard' for context. Artifacts near the top rim of the crater are a result of the transition between the three-dimensional model and the billboard. Portions of the terrain model lacking sufficient data appear as blank spaces or gaps, colored reddish-brown for better viewing. This image was generated using special software from NASA's Ames Research Center and a mosaic of images taken by the rover's panoramic camera.

[figure removed for brevity, see original site] Click on image for larger view

The rocky outcrop traversed by the Mars Exploration Rover Opportunity is visible in this zoomed-in portion of a three-dimensional model of the rover's landing site. Opportunity has acquired close-up images along the way, and scientists are using the rover's instruments to closely examine portions of interest. The white fragments that look crumpled near the center of the image are portions of the airbags. Distant scenery is displayed on a spherical backdrop or 'billboard' for context. Artifacts near the top rim of the crater are a result of the transition between the three-dimensional model and the billboard. Portions of the terrain model lacking sufficient data appear as blank spaces or gaps, colored reddish-brown for better viewing. This image was generated using special software from NASA's Ames Research Center and a mosaic of images taken by the rover's panoramic camera.

Exact results in the large system size limit for the dynamics of the chemical master equation, a one dimensional chain of equations.

PubMed

Martirosyan, A; Saakian, David B

2011-08-01

We apply the Hamilton-Jacobi equation (HJE) formalism to solve the dynamics of the chemical master equation (CME). We found exact analytical expressions (in large system-size limit) for the probability distribution, including explicit expression for the dynamics of variance of distribution. We also give the solution for some simple cases of the model with time-dependent rates. We derived the results of the Van Kampen method from the HJE approach using a special ansatz. Using the Van Kampen method, we give a system of ordinary differential equations (ODEs) to define the variance in a two-dimensional case. We performed numerics for the CME with stationary noise. We give analytical criteria for the disappearance of bistability in the case of stationary noise in one-dimensional CMEs.

3DScapeCS: application of three dimensional, parallel, dynamic network visualization in Cytoscape

PubMed Central

2013-01-01

Background The exponential growth of gigantic biological data from various sources, such as protein-protein interaction (PPI), genome sequences scaffolding, Mass spectrometry (MS) molecular networking and metabolic flux, demands an efficient way for better visualization and interpretation beyond the conventional, two-dimensional visualization tools. Results We developed a 3D Cytoscape Client/Server (3DScapeCS) plugin, which adopted Cytoscape in interpreting different types of data, and UbiGraph for three-dimensional visualization. The extra dimension is useful in accommodating, visualizing, and distinguishing large-scale networks with multiple crossed connections in five case studies. Conclusions Evaluation on several experimental data using 3DScapeCS and its special features, including multilevel graph layout, time-course data animation, and parallel visualization has proven its usefulness in visualizing complex data and help to make insightful conclusions. PMID:24225050

Orbital navigation, docking and obstacle avoidance as a form of three dimensional model-based image understanding

NASA Technical Reports Server (NTRS)

Beyer, J.; Jacobus, C.; Mitchell, B.

1987-01-01

Range imagery from a laser scanner can be used to provide sufficient information for docking and obstacle avoidance procedures to be performed automatically. Three dimensional model-based computer vision algorithms in development can perform these tasks even with targets which may not be cooperative (that is, objects without special targets or markers to provide unambiguous location points). Roll, pitch and yaw of the vehicle can be taken into account as image scanning takes place, so that these can be corrected when the image is converted from egocentric to world coordinates. Other attributes of the sensor, such as the registered reflectence and texture channels, provide additional data sources for algorithm robustness. Temporal fusion of sensor immages can take place in the work coordinate domain, allowing for the building of complex maps in three dimensional space.

Viewing Angle Classification of Cryo-Electron Microscopy Images Using Eigenvectors

PubMed Central

Singer, A.; Zhao, Z.; Shkolnisky, Y.; Hadani, R.

2012-01-01

The cryo-electron microscopy (cryo-EM) reconstruction problem is to find the three-dimensional structure of a macromolecule given noisy versions of its two-dimensional projection images at unknown random directions. We introduce a new algorithm for identifying noisy cryo-EM images of nearby viewing angles. This identification is an important first step in three-dimensional structure determination of macromolecules from cryo-EM, because once identified, these images can be rotationally aligned and averaged to produce “class averages” of better quality. The main advantage of our algorithm is its extreme robustness to noise. The algorithm is also very efficient in terms of running time and memory requirements, because it is based on the computation of the top few eigenvectors of a specially designed sparse Hermitian matrix. These advantages are demonstrated in numerous numerical experiments. PMID:22506089

Rethinking the evolution of specialization: A model for the evolution of phenotypic heterogeneity.

PubMed

Rubin, Ilan N; Doebeli, Michael

2017-12-21

Phenotypic heterogeneity refers to genetically identical individuals that express different phenotypes, even when in the same environment. Traditionally, "bet-hedging" in fluctuating environments is offered as the explanation for the evolution of phenotypic heterogeneity. However, there are an increasing number of examples of microbial populations that display phenotypic heterogeneity in stable environments. Here we present an evolutionary model of phenotypic heterogeneity of microbial metabolism and a resultant theory for the evolution of phenotypic versus genetic specialization. We use two-dimensional adaptive dynamics to track the evolution of the population phenotype distribution of the expression of two metabolic processes with a concave trade-off. Rather than assume a Gaussian phenotype distribution, we use a Beta distribution that is capable of describing genotypes that manifest as individuals with two distinct phenotypes. Doing so, we find that environmental variation is not a necessary condition for the evolution of phenotypic heterogeneity, which can evolve as a form of specialization in a stable environment. There are two competing pressures driving the evolution of specialization: directional selection toward the evolution of phenotypic heterogeneity and disruptive selection toward genetically determined specialists. Because of the lack of a singular point in the two-dimensional adaptive dynamics and the fact that directional selection is a first order process, while disruptive selection is of second order, the evolution of phenotypic heterogeneity dominates and often precludes speciation. We find that branching, and therefore genetic specialization, occurs mainly under two conditions: the presence of a cost to maintaining a high phenotypic variance or when the effect of mutations is large. A cost to high phenotypic variance dampens the strength of selection toward phenotypic heterogeneity and, when sufficiently large, introduces a singular point into the evolutionary dynamics, effectively guaranteeing eventual branching. Large mutations allow the second order disruptive selection to dominate the first order selection toward phenotypic heterogeneity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Leptogenesis from Gravitational Waves and CP Violation

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

Alexander, S

2004-03-05

We present a new mechanism for creating the observed cosmic matter-antimatter asymmetry which satisfies all three Sakharov conditions from one common thread, gravitational waves. We generate lepton number through the gravitational anomaly in the lepton number current. The source term comes from elliptically polarizated gravity waves that are produced during inflation if the inflaton field contains a CP-odd component. In simple inflationary scenarios, the generated matter asymmetry is very small. We describe some special conditions in which our mechanism can give a matter asymmetry of realistic size.

Correlation functions for Hermitian many-body systems: Necessary conditions

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

Brown, E.B.

1994-02-01

Lee [Phys. Rev. B 47, 8293 (1993)] has shown that the odd-numbered derivatives of the Kubo autocorrelation function vanish at [ital t]=0. We show that this condition is based on a more general property of nondiagonal Kubo correlation functions. This general property provides that certain functional forms (e.g., simple exponential decay) are not admissible for any symmetric or antisymmetric Kubo correlation function in a Hermitian many-body system. Lee's result emerges as a special case of this result. Applications to translationally invariant systems and systems with rotational symmetries are also demonstrated.

Birth weight and special educational needs: results of a population-based study in Berlin.

PubMed

Bettge, Susanne; Oberwöhrmann, Sylke; Brockstedt, Matthias; Bührer, Christoph

2014-05-09

Preterm infants are at higher risk for developmental problems. The aim of this study is to quantify the relation between birth weight and special educational needs. We analyzed data from the pre-school examinations of 134 313 children in Berlin aged 5 to 6 who were examined between 2007 and 2011. Special educational needs were diagnosed in 8058 children (6.0%), 4943 (61%) of whom had weighed 3000 g or more at birth. The percentage of children with special educational needs rose steadily with decreasing birth weight (2250-2499 g, 9.2%; 1250-1499 g, 21.1%; less than 750 g, 35.6%). Logistic regression analysis yielded odds ratios and 99% confidence intervals for special educational needs that ranged from 1.32 [1.17-1.47] for birth weight 2750-2999 g to 12.83 [7.48-22.03] for birth weight less than 750 g. Further risk factors were male sex (1.88 [1.75-2.03]), low social status (5.96 [5.21-6.82]), an immigrant background associated with poor German language skills in the family (1.63 [1.43-1.86]), and being raised by a single parent (1.21 [1.12-1.31]). On the other hand, nursery school and/or kindergarten enrollment for at least two years before entering school (0.82 [0.73-0.91]) and an immigrant background with good German skills in the family (0.39 [0.34-0.45]) were associated with lower rates of special educational needs. The risk of special educational needs increases already with moderately decreased birth weight. The most important factor other than birth weight is the family's social status. Although children of very low birth weight have a much higher rate of special educational needs than other children, they still make up only a small percentage of all children with special educational needs.

Classification and Identification of Reading and Math Disabilities: The Special Case of Comorbidity

ERIC Educational Resources Information Center

Branum-Martin, Lee; Fletcher, Jack M.; Stuebing, Karla K.

2013-01-01

Much of learning disabilities research relies on categorical classification frameworks that use psychometric tests and cut points to identify children with reading or math difficulties. However, there is increasing evidence that the attributes of reading and math learning disabilities are dimensional, representing correlated continua of severity.…

... When We "Display" and "Explain" It

ERIC Educational Resources Information Center

Herberholz, Barbara

2010-01-01

Students have completed their two-dimensional drawings, paintings, prints or collages, and there they are--in a neat stack on a shelf. They deserve to be shown to the students, fellow teachers, visiting parents and administrators. They need to be matted or mounted, and placed on exhibit in a corridor, hallway or special bulletin board. By matting…

The Application of "Three Dimensional" Model in the Teaching Design of EFL Writing

ERIC Educational Resources Information Center

Li, Xiping

2013-01-01

As an indispensable and most difficult part of language acquisition, the importance of English writing has been intensified by the economic globalization and internet revolution due to the special role of English as a universal language (Warshauer, 2000). However, writing teaching and learning has been long perplexing language teachers and…

A Systematic, Inquiry-Based 7-Step Virtual Worlds Teacher Training

ERIC Educational Resources Information Center

Nussli, Natalie Christina; Oh, Kevin

2015-01-01

Eighteen special education teachers explored one prominent example of three-dimensional virtual worlds, namely Second Life. This study aimed to (a) determine their perception of the effectiveness of a systematic 7-Step Virtual Worlds Teacher Training workshop in terms of enabling them to make informed decisions about the usability of virtual…

A Dark Horse Medium in Basic Business

ERIC Educational Resources Information Center

Eckert, Sidney W.

1974-01-01

The Dark Horse (DH) board is described and discussed as one medium which may be utilized in the classroom. The DH Board holds fairly heavy three-dimensional display objects and consists of two components: a special material which serves as the display surface and an adhesive material which is fixed to objects displayed. (SC)

Virtual Environments Supporting Learning and Communication in Special Needs Education

ERIC Educational Resources Information Center

Cobb, Sue V. G.

2007-01-01

Virtual reality (VR) describes a set of technologies that allow users to explore and experience 3-dimensional computer-generated "worlds" or "environments." These virtual environments can contain representations of real or imaginary objects on a small or large scale (from modeling of molecular structures to buildings, streets, and scenery of a…

Stationary solutions for the one-dimensional Frémond model of shape memory Effects

NASA Astrophysics Data System (ADS)

Horn, W.

1991-12-01

The objective of this article is to investigate steady state solutions for the Fr'emond theory of shape memory alloys. Special attention is paid to the temperature range where both martensite and austenite appear. We will give a construction of solutions, which involves only elementary mathematical tools.

A More Intuitive Version of the Lorentz Velocity Addition Formula

ERIC Educational Resources Information Center

Devlin, John F.

2009-01-01

The Lorentz velocity addition formula for one-dimensional motion presents a number of problems for beginning students of special relativity. In this paper we suggest a simple rewrite of the formula that is easier for students to memorize and manipulate, and furthermore is more intuitive in understanding the correction necessary when adding…

Global Journal of Computer Science and Technology. Volume 9, Issue 5 (Ver. 2.0)

ERIC Educational Resources Information Center

Dixit, R. K.

2010-01-01

This is a special issue published in version 1.0 of "Global Journal of Computer Science and Technology." Articles in this issue include: (1) [Theta] Scheme (Orthogonal Milstein Scheme), a Better Numerical Approximation for Multi-dimensional SDEs (Klaus Schmitz Abe); (2) Input Data Processing Techniques in Intrusion Detection…

Invariant submanifold for series arrays of Josephson junctions.

PubMed

Marvel, Seth A; Strogatz, Steven H

2009-03-01

We study the nonlinear dynamics of series arrays of Josephson junctions in the large-N limit, where N is the number of junctions in the array. The junctions are assumed to be identical, overdamped, driven by a constant bias current, and globally coupled through a common load. Previous simulations of such arrays revealed that their dynamics are remarkably simple, hinting at the presence of some hidden symmetry or other structure. These observations were later explained by the discovery of N-3 constants of motion, the choice of which confines the resulting flow in phase space to a low-dimensional invariant manifold. Here we show that the dimensionality can be reduced further by restricting attention to a special family of states recently identified by Ott and Antonsen. In geometric terms, the Ott-Antonsen ansatz corresponds to an invariant submanifold of dimension one less than that found earlier. We derive and analyze the flow on this submanifold for two special cases: an array with purely resistive loading and another with resistive-inductive-capacitive loading. Our results recover (and in some instances improve) earlier findings based on linearization arguments.

A novel and compact spectral imaging system based on two curved prisms

NASA Astrophysics Data System (ADS)

Nie, Yunfeng; Bin, Xiangli; Zhou, Jinsong; Li, Yang

2013-09-01

As a novel detection approach which simultaneously acquires two-dimensional visual picture and one-dimensional spectral information, spectral imaging offers promising applications on biomedical imaging, conservation and identification of artworks, surveillance of food safety, and so forth. A novel moderate-resolution spectral imaging system consisting of merely two optical elements is illustrated in this paper. It can realize the function of a relay imaging system as well as a 10nm spectral resolution spectroscopy. Compared to conventional prismatic imaging spectrometers, this design is compact and concise with only two special curved prisms by utilizing two reflective surfaces. In contrast to spectral imagers based on diffractive grating, the usage of compound-prism possesses characteristics of higher energy utilization and wider free spectral range. The seidel aberration theory and dispersive principle of this special prism are analyzed at first. According to the results, the optical system of this design is simulated, and the performance evaluation including spot diagram, MTF and distortion, is presented. In the end, considering the difficulty and particularity of manufacture and alignment, an available method for fabrication and measurement is proposed.

Application of Central Upwind Scheme for Solving Special Relativistic Hydrodynamic Equations

PubMed Central

Yousaf, Muhammad; Ghaffar, Tayabia; Qamar, Shamsul

2015-01-01

The accurate modeling of various features in high energy astrophysical scenarios requires the solution of the Einstein equations together with those of special relativistic hydrodynamics (SRHD). Such models are more complicated than the non-relativistic ones due to the nonlinear relations between the conserved and state variables. A high-resolution shock-capturing central upwind scheme is implemented to solve the given set of equations. The proposed technique uses the precise information of local propagation speeds to avoid the excessive numerical diffusion. The second order accuracy of the scheme is obtained with the use of MUSCL-type initial reconstruction and Runge-Kutta time stepping method. After a discussion of the equations solved and of the techniques employed, a series of one and two-dimensional test problems are carried out. To validate the method and assess its accuracy, the staggered central and the kinetic flux-vector splitting schemes are also applied to the same model. The scheme is robust and efficient. Its results are comparable to those obtained from the sophisticated algorithms, even in the case of highly relativistic two-dimensional test problems. PMID:26070067

Decay of a linear pendulum in a collisional gas: Spatially one-dimensional case

NASA Astrophysics Data System (ADS)

Tsuji, Tetsuro; Aoki, Kazuo

2014-05-01

An infinitely wide plate, subject to an external force in its normal direction obeying Hooke's law, is placed in an infinite expanse of a rarefied gas. When the plate is displaced from its equilibrium position and released, it starts in general an oscillatory motion in its normal direction. This is the one-dimensional setting of a linear pendulum considered previously for a collisionless gas and a special Lorentz gas by the present authors [T. Tsuji and K. Aoki, J. Stat. Phys. 146, 620 (2012), 10.1007/s10955-011-0412-7]. The motion decays as time proceeds because of the drag force on the plate exerted by the surrounding gas. The long-time behavior of the unsteady motion of the gas caused by the motion of the plate is investigated numerically on the basis of the Bhatnagar-Gross-Krook (BGK) model of the Boltzmann equation with special interest in the rate of the decay of the oscillatory motion of the plate. The result provides numerical evidence that the displacement of the plate decays in proportion to an inverse power of time for large time.

Decay of a linear pendulum in a collisional gas: spatially one-dimensional case.

PubMed

Tsuji, Tetsuro; Aoki, Kazuo

2014-05-01

An infinitely wide plate, subject to an external force in its normal direction obeying Hooke's law, is placed in an infinite expanse of a rarefied gas. When the plate is displaced from its equilibrium position and released, it starts in general an oscillatory motion in its normal direction. This is the one-dimensional setting of a linear pendulum considered previously for a collisionless gas and a special Lorentz gas by the present authors [T. Tsuji and K. Aoki, J. Stat. Phys. 146, 620 (2012)]. The motion decays as time proceeds because of the drag force on the plate exerted by the surrounding gas. The long-time behavior of the unsteady motion of the gas caused by the motion of the plate is investigated numerically on the basis of the Bhatnagar-Gross-Krook (BGK) model of the Boltzmann equation with special interest in the rate of the decay of the oscillatory motion of the plate. The result provides numerical evidence that the displacement of the plate decays in proportion to an inverse power of time for large time.

Tomography and the Herglotz-Wiechert inverse formulation

NASA Astrophysics Data System (ADS)

Nowack, Robert L.

1990-04-01

In this paper, linearized tomography and the Herglotz-Wiechert inverse formulation are compared. Tomographic inversions for 2-D or 3-D velocity structure use line integrals along rays and can be written in terms of Radon transforms. For radially concentric structures, Radon transforms are shown to reduce to Abel transforms. Therefore, for straight ray paths, the Abel transform of travel-time is a tomographic algorithm specialized to a one-dimensional radially concentric medium. The Herglotz-Wiechert formulation uses seismic travel-time data to invert for one-dimensional earth structure and is derived using exact ray trajectories by applying an Abel transform. This is of historical interest since it would imply that a specialized tomographic-like algorithm has been used in seismology since the early part of the century (see Herglotz, 1907; Wiechert, 1910). Numerical examples are performed comparing the Herglotz-Wiechert algorithm and linearized tomography along straight rays. Since the Herglotz-Wiechert algorithm is applicable under specific conditions, (the absence of low velocity zones) to non-straight ray paths, the association with tomography may prove to be useful in assessing the uniqueness of tomographic results generalized to curved ray geometries.

Ethnographic analogy, the comparative method, and archaeological special pleading.

PubMed

Currie, Adrian

2016-02-01

Ethnographic analogy, the use of comparative data from anthropology to inform reconstructions of past human societies, has a troubled history. Archaeologists often express concern about, or outright reject, the practice--and sometimes do so in problematically general terms. This is odd, as (or so I argue) the use of comparative data in archaeology is the same pattern of reasoning as the 'comparative method' in biology, which is a well-developed and robust set of inferences which play a central role in discovering the biological past. In pointing out this continuity, I argue that there is no 'special pleading' on the part of archaeologists in this regard: biologists must overcome analogous epistemic difficulties in their use of comparative data. I then go on to emphasize the local, empirically tractable ways in which particular ethnographic analogies may be licensed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phases of higher spin black holes: Hawking-Page, transitions between black holes, and a critical point

NASA Astrophysics Data System (ADS)

Bañados, Máximo; Düring, Gustavo; Faraggi, Alberto; Reyes, Ignacio A.

2017-08-01

We study the thermodynamic phase diagram of three-dimensional s l (N ;R ) higher spin black holes. By analyzing the semiclassical partition function we uncover a rich structure that includes Hawking-Page transitions to the AdS3 vacuum, first order phase transitions among black hole states, and a second order critical point. Our analysis is explicit for N =4 but we extrapolate some of our conclusions to arbitrary N . In particular, we argue that even N is stable in the ensemble under consideration but odd N is not.

Fluxoids behavior in superconducting ladders

NASA Astrophysics Data System (ADS)

Sharon, Omri J.; Haham, Noam; Shaulov, Avner; Yeshurun, Yosef

2018-03-01

The nature of the interaction between fluxoids and between them and the external magnetic field is studied in one-dimensional superconducting networks. An Ising like expression is derived for the energy of a network revealing that fluxoids behave as repulsively interacting objects driven towards the network center by the effective applied field. Competition between these two interactions determines the equilibrium arrangement of fluxoids in the network as a function of the applied field. It is demonstrated that the fluxoids configurations are not always commensurate to the network symmetry. Incommensurate, degenerated configurations may be formed even in networks with an odd number of loops.

Thermodynamics of Einstein-Born-Infeld black holes with negative cosmological constant

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

Miskovic, Olivera; Olea, Rodrigo; INFN, Sezione di Milano, Via Celoria 16, I-20133, Milano

2008-06-15

We study the thermodynamics associated to topological black hole solutions of AdS gravity coupled to nonlinear electrodynamics (Born-Infeld) in any dimension, using a background-independent regularization prescription for the Euclidean action given by boundary terms, which explicitly depend on the extrinsic curvature (Kounterterms series). A finite action principle leads to the correct definition of thermodynamic variables as Noether charges, which satisfy a Smarr-like relation. In particular, for the odd-dimensional case, a consistent thermodynamic description is achieved if the internal energy of the system includes the vacuum energy for AdS spacetime.

Semi-implicit finite difference methods for three-dimensional shallow water flow

USGS Publications Warehouse

Casulli, Vincenzo; Cheng, Ralph T.

1992-01-01

A semi-implicit finite difference method for the numerical solution of three-dimensional shallow water flows is presented and discussed. The governing equations are the primitive three-dimensional turbulent mean flow equations where the pressure distribution in the vertical has been assumed to be hydrostatic. In the method of solution a minimal degree of implicitness has been adopted in such a fashion that the resulting algorithm is stable and gives a maximal computational efficiency at a minimal computational cost. At each time step the numerical method requires the solution of one large linear system which can be formally decomposed into a set of small three-diagonal systems coupled with one five-diagonal system. All these linear systems are symmetric and positive definite. Thus the existence and uniquencess of the numerical solution are assured. When only one vertical layer is specified, this method reduces as a special case to a semi-implicit scheme for solving the corresponding two-dimensional shallow water equations. The resulting two- and three-dimensional algorithm has been shown to be fast, accurate and mass-conservative and can also be applied to simulate flooding and drying of tidal mud-flats in conjunction with three-dimensional flows. Furthermore, the resulting algorithm is fully vectorizable for an efficient implementation on modern vector computers.

Hidden symmetries of Eisenhart-Duval lift metrics and the Dirac equation with flux

NASA Astrophysics Data System (ADS)

Cariglia, Marco

2012-10-01

The Eisenhart-Duval lift allows embedding nonrelativistic theories into a Lorentzian geometrical setting. In this paper we study the lift from the point of view of the Dirac equation and its hidden symmetries. We show that dimensional reduction of the Dirac equation for the Eisenhart-Duval metric in general gives rise to the nonrelativistic Lévy-Leblond equation in lower dimension. We study in detail in which specific cases the lower dimensional limit is given by the Dirac equation, with scalar and vector flux, and the relation between lift, reduction, and the hidden symmetries of the Dirac equation. While there is a precise correspondence in the case of the lower dimensional massive Dirac equation with no flux, we find that for generic fluxes it is not possible to lift or reduce all solutions and hidden symmetries. As a by-product of this analysis, we construct new Lorentzian metrics with special tensors by lifting Killing-Yano and closed conformal Killing-Yano tensors and describe the general conformal Killing-Yano tensor of the Eisenhart-Duval lift metrics in terms of lower dimensional forms. Last, we show how, by dimensionally reducing the higher dimensional operators of the massless Dirac equation that are associated with shared hidden symmetries, it is possible to recover hidden symmetry operators for the Dirac equation with flux.

Attitude Estimation or Quaternion Estimation?

NASA Technical Reports Server (NTRS)

Markley, F. Landis

2003-01-01

The attitude of spacecraft is represented by a 3x3 orthogonal matrix with unity determinant, which belongs to the three-dimensional special orthogonal group SO(3). The fact that all three-parameter representations of SO(3) are singular or discontinuous for certain attitudes has led to the use of higher-dimensional nonsingular parameterizations, especially the four-component quaternion. In attitude estimation, we are faced with the alternatives of using an attitude representation that is either singular or redundant. Estimation procedures fall into three broad classes. The first estimates a three-dimensional representation of attitude deviations from a reference attitude parameterized by a higher-dimensional nonsingular parameterization. The deviations from the reference are assumed to be small enough to avoid any singularity or discontinuity of the three-dimensional parameterization. The second class, which estimates a higher-dimensional representation subject to enough constraints to leave only three degrees of freedom, is difficult to formulate and apply consistently. The third class estimates a representation of SO(3) with more than three dimensions, treating the parameters as independent. We refer to the most common member of this class as quaternion estimation, to contrast it with attitude estimation. We analyze the first and third of these approaches in the context of an extended Kalman filter with simplified kinematics and measurement models.

Unlabored system motion by specially conditioned electromagnetic fields in higher dimensional realms

NASA Astrophysics Data System (ADS)

David Froning, H.; Meholic, Gregory V.

2010-01-01

This third of three papers explores the possibility of swift, stress-less system transitions between slower-than-light and faster-than-light speeds with negligible net expenditure of system energetics. The previous papers derived a realm of higher dimensionality than 4-D spacetime that enabled such unlabored motion; and showed that fields that could propel and guide systems on unlabored paths in the higher dimensional realm must be fields that have been conditioned to SU(2) (or higher) Lie group symmetry. This paper shows that the system's surrounding vacuum dielectric ɛμ, within the higher dimensional realm's is a vector (not scalar) quantity with fixed magnitude ɛ0μ0 and changing direction within the realm with changing system speed. Thus, ɛμ generated by the system's EM field must remain tuned to vacuum ɛ0μ0 in both magnitude and direction during swift, unlabored system transitions between slower and faster than light speeds. As a result, the system's changing path and speed is such that the magnitude of the higher dimensional realm's ɛ0μ0 is not disturbed. And it is shown that a system's flight trajectories associated with its swift, unlabored transitions between zero and infinite speed can be represented by curved paths traced-out within the higher dimensional realm.

Point force and point electric charge applied to the boundary of three-dimensional anisotropic piezoelectric solid

DOE PAGES

Borovikov, V. A.; Kalinin, S. V.; Khavin, Yu.; ...

2015-08-19

We derive the Green's functions for a three-dimensional semi-infinite fully anisotropic piezoelectric material using the plane wave theory method. The solution gives the complete set of electromechanical fields due to an arbitrarily oriented point force and a point electric charge applied to the boundary of the half-space. Moreover, the solution constitutes generalization of Boussinesq's and Cerruti's problems of elastic isotropy for the anisotropic piezoelectric materials. On the example of piezoceramics PZT-6B, the present results are compared with the previously obtained solution for the special case of transversely isotropic piezoelectric solid subjected to the same boundary condition.

Three dimensional α-tunneling in intense laser fields

NASA Astrophysics Data System (ADS)

Kis, Daniel P.; Szilvasi, Reka

2018-04-01

The width and life-time of the quasibound state of the α cluster in intense monochromatic electromagnetic (laser) field are discussed in details. The laser modified three dimensional potential barrier felt by the α particle is investigated analytically in long wave approximation and zero-order approximations with some different nuclear models: Coulomb potential with rectangular well, and with Woods-Saxon type potential. We show that the circularly polarized electromagnetic field and the special parameters of the nuclear potentials determine an enhancement of the decay probability, so the life-time of the quasibound state decreases in few times compared to the case of free field.

A note on the regularity of solutions of infinite dimensional Riccati equations

NASA Technical Reports Server (NTRS)

Burns, John A.; King, Belinda B.

1994-01-01

This note is concerned with the regularity of solutions of algebraic Riccati equations arising from infinite dimensional LQR and LQG control problems. We show that distributed parameter systems described by certain parabolic partial differential equations often have a special structure that smoothes solutions of the corresponding Riccati equation. This analysis is motivated by the need to find specific representations for Riccati operators that can be used in the development of computational schemes for problems where the input and output operators are not Hilbert-Schmidt. This situation occurs in many boundary control problems and in certain distributed control problems associated with optimal sensor/actuator placement.

An alternative to unstructured grids for computing gas dynamic flows around arbitrarily complex two-dimensional bodies

NASA Technical Reports Server (NTRS)

Quirk, James J.

1992-01-01

In this paper we describe an approach for dealing with arbitrary complex, two dimensional geometries, the so-called cartesian boundary method. Conceptually, the cartesian boundary method is quite simple. Solid bodies blank out areas of a background, cartesian mesh, and the resultant cut cells are singled out for special attention. However, there are several obstacles that must be overcome in order to achieve a practical scheme. We present a general strategy that overcomes these obstacles, together with some details of our successful conversion of an adaptive mesh algorithm from a body-fitted code to a cartesian boundary code.

Studying critical string emerging from non-Abelian vortex in four dimensions

DOE PAGES

Koroteev, P.; Shifman, M.; Yung, A.

2016-05-26

Recently a special vortex string was found in a class of soliton vortices supported in four-dimensional Yang–Mills theories that under certain conditions can become infinitely thin and can be interpreted as a critical ten-dimensional string. The appropriate bulk Yang–Mills theory has the U(2) gauge group and the Fayet–Iliopoulos term. It supports semilocal non-Abelian vortices with the world-sheet theory for orientational and size moduli described by the weighted CP(2,2) model. Here, the full target space ismore » $$\\mathbb R$$ 4 x Y 6 where is a non-compact Calabi–Yau space.« less

Assortativity Patterns in Multi-dimensional Inter-organizational Networks: A Case Study of the Humanitarian Relief Sector

NASA Astrophysics Data System (ADS)

Zhao, Kang; Ngamassi, Louis-Marie; Yen, John; Maitland, Carleen; Tapia, Andrea

We use computational tools to study assortativity patterns in multi-dimensional inter-organizational networks on the basis of different node attributes. In the case study of an inter-organizational network in the humanitarian relief sector, we consider not only macro-level topological patterns, but also assortativity on the basis of micro-level organizational attributes. Unlike assortative social networks, this inter-organizational network exhibits disassortative or random patterns on three node attributes. We believe organizations' seek of complementarity is one of the main reasons for the special patterns. Our analysis also provides insights on how to promote collaborations among the humanitarian relief organizations.

Solving time-dependent two-dimensional eddy current problems

NASA Technical Reports Server (NTRS)

Lee, Min Eig; Hariharan, S. I.; Ida, Nathan

1988-01-01

Results of transient eddy current calculations are reported. For simplicity, a two-dimensional transverse magnetic field which is incident on an infinitely long conductor is considered. The conductor is assumed to be a good but not perfect conductor. The resulting problem is an interface initial boundary value problem with the boundary of the conductor being the interface. A finite difference method is used to march the solution explicitly in time. The method is shown. Treatment of appropriate radiation conditions is given special consideration. Results are validated with approximate analytic solutions. Two stringent test cases of high and low frequency incident waves are considered to validate the results.

Factors related to northern goshawk landscape use in the western Great Lakes region

USGS Publications Warehouse

Bruggeman, Jason E.; Andersen, David E.; Woodford, James E.

2014-01-01

Northern Goshawks (Accipiter gentilis) are a species of special conservation concern in the western Great Lakes bioregion and elsewhere in North America, and exhibit landscape-scale spatial use patterns. However, little information exists about Northern Goshawk habitat relations at broad spatial extents, as most existing published information comes from a few locations of relatively small spatial extent and, in some cases, short durations. We used an information-theoretic approach to evaluate competing hypotheses regarding factors (forest canopy cover, successional stage, and heights of the canopy top and base) related to odds of Northern Goshawk landscape use throughout the western Great Lakes bioregion based on an occupancy survey completed in 2008 (Bruggeman et al. 2011). We also combined these data with historical data of Northern Goshawk nest locations in the bioregion from 1979–2006 to evaluate the same competing hypotheses to elucidate long-term trends in use. The odds of Northern Goshawk use in 2008, and from 1979–2008, were positively correlated with average percent canopy cover. In the best-approximating models developed using 1979–2008 data, the odds of landscape use were positively correlated with the percentages of the landscape having canopy heights between 10 m and 25 m, and 25 m and 50 m, and the amount of variability in canopy base height. Also, the odds of landscape use were negatively correlated with the average height at the canopy base. Our results suggest multiple habitat factors were related to Northern Goshawk landscape-scale habitat use, similar to habitat use described at smaller spatial scales in the western Great Lakes bioregion and in western North America and Europe.

Cognitive development in childhood and drinking behaviour over two decades in adulthood.

PubMed

Jefferis, B J M H; Manor, O; Power, C

2008-06-01

Childhood cognition predicts adult morbidity and mortality, potentially working through health behaviours. This study investigates if childhood cognition influences life course (i) non-drinking and (ii) binge drinking and pathways through which this might act-namely, childhood behaviour problems, adult social position and educational qualifications. Prospective cohort of British births in March 1958, with information on cognition at 7, 11 and 16 years and alcohol use at 23, 33 and 42 years. Non-drinkers drank "infrequently/on special occasions" or "never". Binge drinkers consumed >or=10 units/occasion (men) and >or=7 units/occasion (women). Lower cognitive ability increased the odds of non-drinking at each adult survey (for example, for men at 42 years OR 1.52 (95% CI 1.34 to 1.72) per SD decrease in 7-year maths). Associations remained after adjustment for pathway factors (i) behaviour problems, (ii) adult social position and (iii) educational qualifications. Decreased ability rank across childhood (7-16 years) also increased odds of non-drinking at 42 years, but the association operated via pathway factors. Lower 7-year ability elevated the odds of 42-year binge drinking, operating via pathway factors. Declining ability rank across childhood also increased the odds of adult binge drinking; associations operated through behavioural problems, adult social position and qualifications. In women, the decline in risk of binge drinking from an age 23-year peak to 42 years was associated with higher 7-year score. Poorer childhood cognition was associated with non-drinking and binge drinking up to the early 40s. Associations between childhood cognition and drinking status may mediate between childhood cognition and adult health.

Linking landscape characteristics to mineral site use by band-tailed pigeons in Western Oregon: Coarse-filter conservation with fine-filter tuning

USGS Publications Warehouse

Overton, C.T.; Schmitz, R.A.; Casazza, Michael L.

2006-01-01

Mineral sites are scarce resources of high ion concentration used heavily by the Pacific Coast subpopulation of band-tailed pigeons. Over 20% of all known mineral sites used by band-tailed pigeons in western Oregon, including all hot springs, have been abandoned. Prior investigations have not analyzed stand or landscape level habitat composition in relation to band-tailed pigeon use of mineral sites. We used logistic regression models to evaluate the influence of habitat types, identified from Gap Analysis Program (GAP) products at two spatial scales, on the odds of mineral site use in Oregon (n = 69 currently used and 20 historically used). Our results indicated that the odds of current use were negatively associated with non-forested terrestrial and private land area around mineral sites. Similarly, the odds of current mineral site use were positively associated with forested and special status (GAP stewardship codes 1 and 2) land area. The most important variable associated with the odds of mineral site use was the amount of non-forested land cover at either spatial scale. Our results demonstrate the utility of meso-scale geographic information designed for regional, coarse-filter approaches to conservation in fine-filter investigation of wildlife-habitat relationships. Adjacent landcover and ownership status explain the pattern of use for known mineral sites in western Oregon. In order for conservation and management activities for band-tailed pigeons to be successful, mineral sites need to be addressed as important and vulnerable resources. Management of band-tailed pigeons should incorporate the potential for forest management activities and land ownership patterns to influence the risk of mineral site abandonment.

Personality Traits Predict Emergency Department Utilization Over 3 Years in Older Patients

PubMed Central

Chapman, Benjamin P.; Shah, Manish; Friedman, Bruce; Drayer, Rebecca; Duberstein, Paul R.; Lyness, Jeffrey M.

2009-01-01

Background Emergency department (ED) utilization by older patients has major implications for morbidity, mortality, and health costs, yet its behavioral determinants remain poorly understood. Powerfully tied to health in older adults, the “Big Five” personality traits of neuroticism, extroversion, openness to experience, agreeableness, and conscientiousness may predict ED use. Objectives Investigate the role of personality in prospective ED use among older patients. Research Design Prospective cohort. Subjects Adults aged 65 and older. Measures Participants completed the NEO Five Factor Inventory of personality at baseline, and interviewers administered the Cornell Services Index assessing ED use at baseline and 3 yearly follow-ups. Results Controlling for income, education, gender, age, physician-assessed medical burden and physical functioning, and interviewer-assessed impairments in basic activities of daily living and physical self-maintenance, and depression, lower agreeableness and higher extroversion were each associated with increased odds of an ED visit over the follow-up period. A 1 sample deviation (SD) increase in extroversion (i.e., 50th versus 83rd population percentile) increased the odds of ED use by 51% (adjusted odds ratio [AOR] [95% CI] = 1.51 [1.03-2.21], z = 2.12, N = 923, p = 0.034). A 1-SD decrease in agreeableness (i.e., 50th versus 17th population percentile) increased odds of ED use by 54% (AOR [95% CI] = 1.54 [1.05-2.22], z = -2.25, N = 923, p = 0.034). Conclusion The greater assertiveness and social confidence signified by lower agreeableness and higher extroversion may help older adults overcome potential barriers to the ED. Overly introverted and agreeable older adults may require special encouragement to access the ED—particularly for time-sensitive conditions—to reduce morbidity and mortality. PMID:19461261

The transformation of targeted killing and international order

PubMed Central

Senn, Martin; Troy, Jodok

2017-01-01

ABSTRACT This article introduces the special issue’s question of whether and how the current transformation of targeted killing is transforming the global international order and provides the conceptual ground for the individual contributions to the special issue. It develops a two-dimensional concept of political order and introduces a theoretical framework that conceives the maintenance and transformation of international order as a dynamic interplay between its behavioral dimension in the form of violence and discursive processes and its institutional dimension in the form of ideas, norms, and rules. The article also conceptualizes targeted killing and introduces a typology of targeted-killing acts on the basis of their legal and moral legitimacy. Building on this conceptual groundwork, the article takes stock of the current transformation of targeted killing and summarizes the individual contributions to this special issue. PMID:29097903

Microscopic description of fission in odd-mass uranium and plutonium nuclei with the Gogny energy density functional

NASA Astrophysics Data System (ADS)

Rodrıguez-Guzmán, R.; Robledo, L. M.

2017-12-01

The parametrization D1M of the Gogny energy density functional is used to study fission in the odd-mass Uranium and Plutonium isotopes with A=233, \\ldots , 249 within the framework of the Hartree-Fock-Bogoliubov (HFB) Equal Filling Approximation (EFA). Ground state quantum numbers and deformations, pairing energies, one-neutron separation energies, barrier heights and fission isomer excitation energies are given. Fission paths, collective masses and zero point rotational and vibrational quantum corrections are used to compute the systematic of the spontaneous fission half-lives t_{SF}, the masses and charges of the fission fragments as well as their intrinsic shapes. Although there exits a strong variance of the predicted fission rates with respect to the details involved in their computation, it is shown that both the specialization energy and the pairing quenching effects, taken into account fully variationally within the HFB-EFA blocking scheme, lead to larger spontaneous fission half-lives in odd-mass U and Pu nuclei as compared with the corresponding even-even neighbors. It is shown that modifications of a few percent in the strengths of the neutron and proton pairing fields can have a significant impact on the collective masses leading to uncertainties of several orders of magnitude in the predicted t_{SF} values. Alpha-decay lifetimes have also been computed using a parametrization of the Viola-Seaborg formula.

Target and double spin asymmetries of deeply virtual π0 production with a longitudinally polarized proton target and CLAS

NASA Astrophysics Data System (ADS)

Kim, A.; Avakian, H.; Burkert, V.; Joo, K.; Kim, W.; Adhikari, K. P.; Akbar, Z.; Anefalos Pereira, S.; Badui, R. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Bosted, P.; Briscoe, W. J.; Brooks, W. K.; Bültmann, S.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chetry, T.; Colaneri, L.; Cole, P. L.; Compton, N.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Djalali, C.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fedotov, G.; Fersch, R.; Filippi, A.; Fleming, J. A.; Fradi, A.; Garc con, M.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guo, L.; Hafidi, K.; Hanretty, C.; Hattawy, M.; Heddle, D.; Hicks, K.; Holtrop, M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joosten, S.; Keller, D.; Khachatryan, G.; Khandaker, M.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mattione, P.; McCracken, M. E.; McKinnon, B.; Mokeev, V.; Movsisyan, A.; Munevar, E.; Nadel-Turonski, P.; Net, L. A.; Niccolai, S.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Park, K.; Pasyuk, E.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Salgado, C.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Zachariou, N.; Zana, L.; Zhang, J.

2017-05-01

The target and double spin asymmetries of the exclusive pseudoscalar channel e → p → → epπ0 were measured for the first time in the deep-inelastic regime using a longitudinally polarized 5.9 GeV electron beam and a longitudinally polarized proton target at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS). The data were collected over a large kinematic phase space and divided into 110 four-dimensional bins of Q2, xB, -t and ϕ. Large values of asymmetry moments clearly indicate a substantial contribution to the polarized structure functions from transverse virtual photon amplitudes. The interpretation of experimental data in terms of generalized parton distributions (GPDs) provides the first insight on the chiral-odd GPDs H˜T and ET, and complement previous measurements of unpolarized structure functions sensitive to the GPDs HT and EbarT. These data provide a crucial input for parametrizations of essentially unknown chiral-odd GPDs and will strongly influence existing theoretical calculations based on the handbag formalism.

Mesospheric ozone measurements by SAGE II

NASA Technical Reports Server (NTRS)

Chu, D. A.; Cunnold, D. M.

1994-01-01

SAGE II observations of ozone at sunrise and sunset (solar zenith angle = 90 deg) at approximately the same tropical latitude and on the same day exhibit larger concentrations at sunrise than at sunset between 55 and 65 km. Because of the rapid conversion between atomic oxygen and ozone, the onion-peeling scheme used in SAGE II retrievals, which is based on an assumption of constant ozone, is invalid. A one-dimensional photochemical model is used to simulate the diurnal variation of ozone particularly within the solar zenith angle of 80 deg - 100 deg. This model indicates that the retrieved SAGE II sunrise and sunset ozone values are both overestimated. The Chapman reactions produce an adequate simulation of the ozone sunrise/sunset ratio only below 60 km, while above 60 km this ratio is highly affected by the odd oxygen loss due to odd hydrogen reactions, particularly OH. The SAGE II ozone measurements are in excellent agreement with model results to which an onion peeling procedure is applied. The SAGE II ozone observations provide information on the mesospheric chemistry not only through the ozone profile averages but also from the sunrise/sunset ratio.

Target and double spin asymmetries of deeply virtual π 0 production with a longitudinally polarized proton target and CLAS

DOE PAGES

Kim, A.; Avakian, H.; Burkert, V.; ...

2017-02-22

The target and double spin asymmetries of the exclusive pseudoscalar channelmore » $$\\vec e\\vec p\\to ep\\pi^0$$ were measured for the first time in the deep-inelastic regime using a longitudinally polarized 5.9 GeV electron beam and a longitudinally polarized proton target at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS). The data were collected over a large kinematic phase space and divided into 110 four-dimensional bins of $Q^2$, $$x_B$$, $-t$ and $$\\phi$$. Large values of asymmetry moments clearly indicate a substantial contribution to the polarized structure functions from transverse virtual photon amplitudes. The interpretation of experimental data in terms of generalized parton distributions (GPDs) provides the first insight on the chiral-odd GPDs $$\\tilde{H}_T$$ and $$E_T$$, and complement previous measurements of unpolarized structure functions sensitive to the GPDs $$H_T$$ and $$\\bar E_T$$. Finally, these data provide necessary constraints for chiral-odd GPD parametrizations and will strongly influence existing theoretical handbag models.« less

Shortcut loading a Bose–Einstein condensate into an optical lattice

NASA Astrophysics Data System (ADS)

Zhou, Xiaoji; Jin, Shengjie; Schmiedmayer, Jörg

2018-05-01

We present an effective and fast (few microseconds) procedure for transferring a Bose–Einstein condensate from the ground state in a harmonic trap into the desired bands of an optical lattice. Our shortcut method is a designed pulse sequence where the time duration and the interval in each step are fully optimized in order to maximize robustness and fidelity of the final state with respect to the target state. The atoms can be prepared in a single band with even or odd parity, and superposition states of different bands can be prepared and manipulated. Furthermore, we extend this idea to the case of two-dimensional or three-dimensional optical lattices where the energies of excited states are degenerate. We experimentally demonstrate various examples and show very good agreement with the theoretical model. Efficient shortcut methods will find applications in the preparation of quantum systems, in quantum information processing, in precise measurement and as a starting point to investigate dynamics in excited bands.

Sounding rocket thermal analysis techniques applied to GAS payloads. [Get Away Special payloads (STS)

NASA Technical Reports Server (NTRS)

Wing, L. D.

1979-01-01

Simplified analytical techniques of sounding rocket programs are suggested as a means of bringing the cost of thermal analysis of the Get Away Special (GAS) payloads within acceptable bounds. Particular attention is given to two methods adapted from sounding rocket technology - a method in which the container and payload are assumed to be divided in half vertically by a thermal plane of symmetry, and a method which considers the container and its payload to be an analogous one-dimensional unit having the real or correct container top surface area for radiative heat transfer and a fictitious mass and geometry which model the average thermal effects.

Specialized stroke services: a meta-analysis comparing three models of care.

PubMed

Foley, Norine; Salter, Katherine; Teasell, Robert

2007-01-01

Using previously published data, the purpose of this study was to identify and discriminate between three different forms of inpatient stroke care based on timing and duration of treatment and to compare the results of clinically important outcomes. Randomized controlled trials, including a recent review of inpatient stroke unit/rehabilitation care, were identified and grouped into three models of care as follows: (a) acute stroke unit care (patients admitted within 36 h of stroke onset and remaining for up to 2 weeks; n = 5), (b) units combining acute and rehabilitative care (combined; n = 4), and (c) rehabilitation units where patients were transferred onto the service approximately 2 weeks following stroke (post-acute; n = 5). Pooled analyses for the outcomes of mortality, combined death and dependency and length of hospital stay were calculated for each model of care, compared to conventional care. All three models of care were associated with significant reductions in the odds of combined death and dependency; however, acute stroke units were not associated with significant reductions in mortality when this outcome was analyzed separately (OR 0.80; 95% CI: 0.61-1.03). Post-acute stroke units were associated with the greatest reduction in the odds of mortality (OR 0.60; 95% CI: 0.44-0.81). Significant reductions in length of hospital stay were associated with combined stroke units only (weighted mean difference -14 days; 95% CI: -27 to -2). Overall, specialized stroke services were associated with significant reductions in mortality, death and dependency and length of hospital stay although not every model of care was associated with equal benefit.

Receipt of preventive oral health care by U.S. children: a population-based study of the 2005-2008 medical expenditure panel surveys.

PubMed

Huebner, Colleen E; Bell, Janice F; Reed, Sarah C

2013-11-01

This study provides estimates of the annual use of preventive oral health care by U.S. children ages 6 months-17 years. We estimated the annual use of preventive oral health care with data from the Medical Expenditure Panel Survey for the years 2005 through 2008 (n = 18,218). Additionally, we tested associations between use of preventive oral health care and predisposing factors, enabling factors and health need within three age groups: young children, school-age children and youth. Overall, 21 % of the sample was reported to have received preventive oral health care in the prior year. More school-age children received preventive care than did young children or youth regardless of gender, race/ethnicity, health status, residence, or family size. Among the youngest children, low parental education and lack of health insurance were associated with lower odds of receiving preventive care. School-age children of racial and ethnic minority groups had a higher odds of receiving preventive care than did non-Hispanic Whites. Youth with special health care needs were less likely to receive care than their peers. Within each age group, use of preventive care increased significantly from 2005 to 2008. In the U.S. there has been an increase in use of pediatric preventive dental care. Continued effort is needed to achieve primary prevention. Outreach and education should include all parents and especially parents with low levels of education, parents of children with special health care needs and those without health insurance.

Improving End-of-Life Care: Palliative Care Embedded in an Oncology Clinic Specializing in Targeted and Immune-Based Therapies.

PubMed

Einstein, David J; DeSanto-Madeya, Susan; Gregas, Matthew; Lynch, Jessica; McDermott, David F; Buss, Mary K

2017-09-01

Patients with advanced cancer benefit from early involvement of palliative care. The ideal method of palliative care integration remains to be determined, as does its effectiveness for patients treated with targeted and immune-based therapies. We studied the impact of an embedded palliative care team that saw patients in an academic oncology clinic specializing in targeted and immune-based therapies. Patients seen on a specific day accessed the embedded model, on the basis of automatic criteria; patients seen other days could be referred to a separate palliative care clinic (usual care). We abstracted data from the medical records of 114 patients who died during the 3 years after this model's implementation. Compared with usual care (n = 88), patients with access to the embedded model (n = 26) encountered palliative care as outpatients more often ( P = .003) and earlier (mean, 231 v 109 days before death; P < .001). Hospice enrollment rates were similar ( P = .303), but duration was doubled (mean, 57 v 25 days; P = .006), and enrollment > 7 days before death-a core Quality Oncology Practice Initiative metric-was higher in the embedded model (odds ratio, 5.60; P = .034). Place of death ( P = .505) and end-of-life chemotherapy (odds ratio, 0.361; P = .204) did not differ between the two arms. A model of embedded and automatically triggered palliative care among patients treated exclusively with targeted and immune-based therapies was associated with significant improvements in use and timing of palliative care and hospice, compared with usual practice.

Fast Neural Solution Of A Nonlinear Wave Equation

NASA Technical Reports Server (NTRS)

Barhen, Jacob; Toomarian, Nikzad

1996-01-01

Neural algorithm for simulation of class of nonlinear wave phenomena devised. Numerically solves special one-dimensional case of Korteweg-deVries equation. Intended to be executed rapidly by neural network implemented as charge-coupled-device/charge-injection device, very-large-scale integrated-circuit analog data processor of type described in "CCD/CID Processors Would Offer Greater Precision" (NPO-18972).

Early Differentiation within the Animate Domain: Are Humans Something Special?

ERIC Educational Resources Information Center

Pauen, Sabina

2000-01-01

Two experiments investigated whether preverbal infants distinguish between humans and mammals. Study 1 found that 7-, 9-, and 11-month-olds distinguished humans from mammals in an object-examination task. Study 2 found that 7-month-olds but not 5-month-olds showed evidence for category discrimination with the 2-dimensional color photos of toy…

Elements of a modern turbomachinery design system

NASA Astrophysics Data System (ADS)

Jennions, Ian K.

1994-05-01

The aerodynamic design system at GE Aircraft Engines (GEAE) consists of many parts: throughflow, secondary flow, geometry generators, blade-to-blade and fully three-dimensional (3D) analysis. This paper describes each of these elements and discusses optimization and computer architecture issues. Emphasis is placed on those areas in which the company is thought to have special capability.

The MicronEye Motion Monitor: A New Tool for Class and Laboratory Demonstrations.

ERIC Educational Resources Information Center

Nissan, M.; And Others

1988-01-01

Describes a special camera that can be directly linked to a computer that has been adapted for studying movement. Discusses capture, processing, and analysis of two-dimensional data with either IBM PC or Apple II computers. Gives examples of a variety of mechanical tests including pendulum motion, air track, and air table. (CW)

Puzzling Science: Using the Rubik's Cube to Teach Problem Solving

ERIC Educational Resources Information Center

Rohrig, Brian

2010-01-01

A major goal of education is to help learners store information in long-term memory and use that information on later occasions to effectively solve problems (Vockell 2010). Therefore, this author began to use the Rubik's cube to help students learn to problem solve. There is something special about this colorful three-dimensional puzzle that…

Angular integrals in d dimensions

NASA Astrophysics Data System (ADS)

Somogyi, Gábor

2011-08-01

We discuss the evaluation of certain d-dimensional angular integrals which arise in perturbative field theory calculations. We find that the angular integral with n denominators can be computed in terms of a certain special function, the so-called H-function of several variables. We also present several illustrative examples of the general result and briefly consider some applications.

Televirtuality: "Being There" in the 21st Century.

ERIC Educational Resources Information Center

Jacobson, Robert

Virtual worlds technology (VWT) uses special computer hardware and software to link humans with computers in natural ways. A data model, or virtual world, is created and presented as a three-dimensional world of sights and sounds. The participant manipulates apparent objects in the world, and in so doing, alters the data model. VWT will become…

The exact solutions and approximate analytic solutions of the (2 + 1)-dimensional KP equation based on symmetry method.

PubMed

Gai, Litao; Bilige, Sudao; Jie, Yingmo

2016-01-01

In this paper, we successfully obtained the exact solutions and the approximate analytic solutions of the (2 + 1)-dimensional KP equation based on the Lie symmetry, the extended tanh method and the homotopy perturbation method. In first part, we obtained the symmetries of the (2 + 1)-dimensional KP equation based on the Wu-differential characteristic set algorithm and reduced it. In the second part, we constructed the abundant exact travelling wave solutions by using the extended tanh method. These solutions are expressed by the hyperbolic functions, the trigonometric functions and the rational functions respectively. It should be noted that when the parameters are taken as special values, some solitary wave solutions are derived from the hyperbolic function solutions. Finally, we apply the homotopy perturbation method to obtain the approximate analytic solutions based on four kinds of initial conditions.

Three-dimensional fine structure of the organization of microtubules in neurite varicosities by ultra-high voltage electron microscope tomography.

PubMed

Nishida, Tomoki; Yoshimura, Ryoichi; Endo, Yasuhisa

2017-09-01

Neurite varicosities are highly specialized compartments that are involved in neurotransmitter/ neuromodulator release and provide a physiological platform for neural functions. However, it remains unclear how microtubule organization contributes to the form of varicosity. Here, we examine the three-dimensional structure of microtubules in varicosities of a differentiated PC12 neural cell line using ultra-high voltage electron microscope tomography. Three-dimensional imaging showed that a part of the varicosities contained an accumulation of organelles that were separated from parallel microtubule arrays. Further detailed analysis using serial sections and whole-mount tomography revealed microtubules running in a spindle shape of swelling in some other types of varicosities. These electron tomographic results showed that the structural diversity and heterogeneity of microtubule organization supported the form of varicosities, suggesting that a different distribution pattern of microtubules in varicosities is crucial to the regulation of varicosities development.

DNA molecules on periodically microstructured lipid membranes: Localization and coil stretching

NASA Astrophysics Data System (ADS)

Hochrein, Marion B.; Leierseder, Judith A.; Golubović, Leonardo; Rädler, Joachim O.

2007-02-01

We explore large scale conformations of DNA molecules adsorbed on curved surfaces. For that purpose, we investigate the behavior of DNA adsorbed on periodically shaped cationic lipid membranes. These unique membrane morphologies are supported on grooved, one-dimensionally periodic microstructured surfaces. Strikingly, we find that these periodically structured membranes are capable to stretch DNA coils. We elucidate this phenomenon in terms of surface curvature dependent potential energy attained by the adsorbed DNA molecules. Due to it, DNA molecules undergo a localization transition causing them to stretch by binding to highly curved sections (edges) of the supported membranes. This effect provides a new venue for controlling conformations of semiflexible polymers such as DNA by employing their interactions with specially designed biocompatible surfaces. We report the first experimental observation of semiflexible polymers unbinding transition in which DNA molecules unbind from one-dimensional manifolds (edges) while remaining bound to two-dimensional manifolds (cationic membranes).

Application of Tessellation in Architectural Geometry Design

NASA Astrophysics Data System (ADS)

Chang, Wei

2018-06-01

Tessellation plays a significant role in architectural geometry design, which is widely used both through history of architecture and in modern architectural design with the help of computer technology. Tessellation has been found since the birth of civilization. In terms of dimensions, there are two- dimensional tessellations and three-dimensional tessellations; in terms of symmetry, there are periodic tessellations and aperiodic tessellations. Besides, some special types of tessellations such as Voronoi Tessellation and Delaunay Triangles are also included. Both Geometry and Crystallography, the latter of which is the basic theory of three-dimensional tessellations, need to be studied. In history, tessellation was applied into skins or decorations in architecture. The development of Computer technology enables tessellation to be more powerful, as seen in surface control, surface display and structure design, etc. Therefore, research on the application of tessellation in architectural geometry design is of great necessity in architecture studies.

Cattaneo-Christov Heat Flux Model for MHD Three-Dimensional Flow of Maxwell Fluid over a Stretching Sheet.

PubMed

Rubab, Khansa; Mustafa, M

2016-01-01

This letter investigates the MHD three-dimensional flow of upper-convected Maxwell (UCM) fluid over a bi-directional stretching surface by considering the Cattaneo-Christov heat flux model. This model has tendency to capture the characteristics of thermal relaxation time. The governing partial differential equations even after employing the boundary layer approximations are non linear. Accurate analytic solutions for velocity and temperature distributions are computed through well-known homotopy analysis method (HAM). It is noticed that velocity decreases and temperature rises when stronger magnetic field strength is accounted. Penetration depth of temperature is a decreasing function of thermal relaxation time. The analysis for classical Fourier heat conduction law can be obtained as a special case of the present work. To our knowledge, the Cattaneo-Christov heat flux model law for three-dimensional viscoelastic flow problem is just introduced here.

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

Dehghani, M.H.; Research Institute for Astrophysics and Astronomy of Maragha; Khodam-Mohammadi, A.

First, we construct the Taub-NUT/bolt solutions of (2k+2)-dimensional Einstein-Maxwell gravity, when all the factor spaces of 2k-dimensional base space B have positive curvature. These solutions depend on two extra parameters, other than the mass and the NUT charge. These are electric charge q and electric potential at infinity V. We investigate the existence of Taub-NUT solutions and find that in addition to the two conditions of uncharged NUT solutions, there exist two extra conditions. These two extra conditions come from the regularity of vector potential at r=N and the fact that the horizon at r=N should be the outer horizonmore » of the NUT charged black hole. We find that the NUT solutions in 2k+2 dimensions have no curvature singularity at r=N, when the 2k-dimensional base space is chosen to be CP{sup 2k}. For bolt solutions, there exists an upper limit for the NUT parameter which decreases as the potential parameter increases. Second, we study the thermodynamics of these spacetimes. We compute temperature, entropy, charge, electric potential, action and mass of the black hole solutions, and find that these quantities satisfy the first law of thermodynamics. We perform a stability analysis by computing the heat capacity, and show that the NUT solutions are not thermally stable for even k's, while there exists a stable phase for odd k's, which becomes increasingly narrow with increasing dimensionality and wide with increasing V. We also study the phase behavior of the 4 and 6 dimensional bolt solutions in canonical ensemble and find that these solutions have a stable phase, which becomes smaller as V increases.« less

Three-dimensional Majorana fermions in chiral superconductors

DOE PAGES

Kozii, Vladyslav; Venderbos, Jorn W. F.; Fu, Liang

2016-12-07

Using a systematic symmetry and topology analysis, we establish that three-dimensional chiral superconductors with strong spin-orbit coupling and odd-parity pairing generically host low-energy nodal quasiparticles that are spin-nondegenerate and realize Majorana fermions in three dimensions. By examining all types of chiral Cooper pairs with total angular momentum J formed by Bloch electrons with angular momentum j in crystals, we obtain a comprehensive classification of gapless Majorana quasiparticles in terms of energy-momentum relation and location on the Fermi surface. We show that the existence of bulk Majorana fermions in the vicinity of spin-selective point nodes is rooted in the nonunitary naturemore » of chiral pairing in spin-orbit–coupled superconductors. We address experimental signatures of Majorana fermions and find that the nuclear magnetic resonance spin relaxation rate is significantly suppressed for nuclear spins polarized along the nodal direction as a consequence of the spin-selective Majorana nature of nodal quasiparticles. Furthermore, Majorana nodes in the bulk have nontrivial topology and imply the presence of Majorana bound states on the surface, which form arcs in momentum space. We conclude by proposing the heavy fermion superconductor PrOs 4Sb 12 and related materials as promising candidates for nonunitary chiral superconductors hosting three-dimensional Majorana fermions.« less

Three-dimensional Majorana fermions in chiral superconductors.

PubMed

Kozii, Vladyslav; Venderbos, Jörn W F; Fu, Liang

2016-12-01

Using a systematic symmetry and topology analysis, we establish that three-dimensional chiral superconductors with strong spin-orbit coupling and odd-parity pairing generically host low-energy nodal quasiparticles that are spin-nondegenerate and realize Majorana fermions in three dimensions. By examining all types of chiral Cooper pairs with total angular momentum J formed by Bloch electrons with angular momentum j in crystals, we obtain a comprehensive classification of gapless Majorana quasiparticles in terms of energy-momentum relation and location on the Fermi surface. We show that the existence of bulk Majorana fermions in the vicinity of spin-selective point nodes is rooted in the nonunitary nature of chiral pairing in spin-orbit-coupled superconductors. We address experimental signatures of Majorana fermions and find that the nuclear magnetic resonance spin relaxation rate is significantly suppressed for nuclear spins polarized along the nodal direction as a consequence of the spin-selective Majorana nature of nodal quasiparticles. Furthermore, Majorana nodes in the bulk have nontrivial topology and imply the presence of Majorana bound states on the surface, which form arcs in momentum space. We conclude by proposing the heavy fermion superconductor PrOs 4 Sb 12 and related materials as promising candidates for nonunitary chiral superconductors hosting three-dimensional Majorana fermions.

Three-dimensional Majorana fermions in chiral superconductors

PubMed Central

Kozii, Vladyslav; Venderbos, Jörn W. F.; Fu, Liang

2016-01-01

Using a systematic symmetry and topology analysis, we establish that three-dimensional chiral superconductors with strong spin-orbit coupling and odd-parity pairing generically host low-energy nodal quasiparticles that are spin-nondegenerate and realize Majorana fermions in three dimensions. By examining all types of chiral Cooper pairs with total angular momentum J formed by Bloch electrons with angular momentum j in crystals, we obtain a comprehensive classification of gapless Majorana quasiparticles in terms of energy-momentum relation and location on the Fermi surface. We show that the existence of bulk Majorana fermions in the vicinity of spin-selective point nodes is rooted in the nonunitary nature of chiral pairing in spin-orbit–coupled superconductors. We address experimental signatures of Majorana fermions and find that the nuclear magnetic resonance spin relaxation rate is significantly suppressed for nuclear spins polarized along the nodal direction as a consequence of the spin-selective Majorana nature of nodal quasiparticles. Furthermore, Majorana nodes in the bulk have nontrivial topology and imply the presence of Majorana bound states on the surface, which form arcs in momentum space. We conclude by proposing the heavy fermion superconductor PrOs4Sb12 and related materials as promising candidates for nonunitary chiral superconductors hosting three-dimensional Majorana fermions. PMID:27957543

Impact of specialized inpatient IBD care on outcomes of IBD hospitalizations: A cohort study

PubMed Central

Law, Cindy CY; Sasidharan, Saranya; Rodrigues, Rodrigo; Nguyen, Deanna D; Sauk, Jenny; Garber, John; Giallourakis, Cosmas; Xavier, Ramnik; Khalili, Hamed; Yajnik, Vijay; Ananthakrishnan, Ashwin N

2016-01-01

Background The management of inflammatory bowel diseases (IBD; Crohn’s disease (CD), ulcerative colitis (UC)) is increasingly complex. Specialized care has been associated with improved ambulatory IBD outcomes. Aims To examine if the implementation of specialized inpatient IBD care modified short and long-term clinical outcomes in IBD-related hospitalizations. Methods This retrospective cohort study included IBD patients hospitalized between July 2013 and April 2015 at a single tertiary referral center where a specialized inpatient IBD care model was implemented in July 2014. In-hospital medical and surgical outcomes as well as post-discharge outcomes at 30 and 90 days were analyzed along with measures of quality of in-hospital care. Effect of specialist IBD care was examined on multivariate analysis. Results A total of 408 IBD-related admissions were included. With implementation of specialized IBD inpatient care, we observed increased frequency of use of high-dose biologic therapy for induction (26% vs. 9%, odds ratio (OR) 5.50, 95% CI 1.30 – 23.17) and higher proportion of patients in remission at 90 days after discharge (multivariate OR 1.60, 95% CI 0.99 – 2.69). While there was no difference in surgery by 90 days, among those who underwent surgery, early surgery defined as in-hospital or within 30 days of discharge, was more common in the study period (71%) compared to the control period (46%, multivariate OR 2.73, 95% CI 1.22 – 6.12). There was no difference in length of stay between the two years. Conclusions Implementation of specialized inpatient IBD care beneficially impacted remission and facilitated early surgical treatment. PMID:27482978

Thermal Pollution Math Model. Volume 1. Thermal Pollution Model Package Verification and Transfer. [environment impact of thermal discharges from power plants

NASA Technical Reports Server (NTRS)

Lee, S. S.; Sengupta, S.

1980-01-01

Two three dimensional, time dependent models, one free surface, the other rigid lid, were verified at Anclote Anchorage and Lake Keowee respectively. The first site is a coastal site in northern Florida; the other is a man-made lake in South Carolina. These models describe the dispersion of heated discharges from power plants under the action of ambient conditions. A one dimensional, horizontally-averaged model was also developed and verified at Lake Keowee. The data base consisted of archival in situ measurements and data collected during field missions. The field missions were conducted during winter and summer conditions at each site. Each mission consisted of four infrared scanner flights with supporting ground truth and in situ measurements. At Anclote, special care was taken to characterize the complete tidal cycle. The three dimensional model results compared with IR data for thermal plumes on an average within 1 C root mean square difference. The one dimensional model performed satisfactorily in simulating the 1971-1979 period.

A new family of N dimensional superintegrable double singular oscillators and quadratic algebra Q(3) ⨁ so(n) ⨁ so(N-n)

NASA Astrophysics Data System (ADS)

Fazlul Hoque, Md; Marquette, Ian; Zhang, Yao-Zhong

2015-11-01

We introduce a new family of N dimensional quantum superintegrable models consisting of double singular oscillators of type (n, N-n). The special cases (2,2) and (4,4) have previously been identified as the duals of 3- and 5-dimensional deformed Kepler-Coulomb systems with u(1) and su(2) monopoles, respectively. The models are multiseparable and their wave functions are obtained in (n, N-n) double-hyperspherical coordinates. We obtain the integrals of motion and construct the finitely generated polynomial algebra that is the direct sum of a quadratic algebra Q(3) involving three generators, so(n), so(N-n) (i.e. Q(3) ⨁ so(n) ⨁ so(N-n)). The structure constants of the quadratic algebra itself involve the Casimir operators of the two Lie algebras so(n) and so(N-n). Moreover, we obtain the finite dimensional unitary representations (unirreps) of the quadratic algebra and present an algebraic derivation of the degenerate energy spectrum of the superintegrable model.

Black holes, hidden symmetries, and complete integrability

NASA Astrophysics Data System (ADS)

Frolov, Valeri P.; Krtouš, Pavel; Kubizňák, David

2017-11-01

The study of higher-dimensional black holes is a subject which has recently attracted vast interest. Perhaps one of the most surprising discoveries is a realization that the properties of higher-dimensional black holes with the spherical horizon topology and described by the Kerr-NUT-(A)dS metrics are very similar to the properties of the well known four-dimensional Kerr metric. This remarkable result stems from the existence of a single object called the principal tensor. In our review we discuss explicit and hidden symmetries of higher-dimensional Kerr-NUT-(A)dS black hole spacetimes. We start with discussion of the Killing and Killing-Yano objects representing explicit and hidden symmetries. We demonstrate that the principal tensor can be used as a "seed object" which generates all these symmetries. It determines the form of the geometry, as well as guarantees its remarkable properties, such as special algebraic type of the spacetime, complete integrability of geodesic motion, and separability of the Hamilton-Jacobi, Klein-Gordon, and Dirac equations. The review also contains a discussion of different applications of the developed formalism and its possible generalizations.

Three-dimensional numerical study of heat transfer enhancement in separated flows

NASA Astrophysics Data System (ADS)

Kumar, Saurav; Vengadesan, S.

2017-11-01

The flow separation appears in a wide range of heat transfer applications and causes poor heat transfer performance. It motivates the study of heat transfer enhancement in laminar as well as turbulent flows over a backward facing step by means of an adiabatic fin mounted on the top wall. Recently, we have studied steady, 2-D numerical simulations in laminar flow and investigated the effect of fin length, location, and orientation. It revealed that the addition of fin causes enhancement of heat transfer and it is very effective to control the flow and thermal behavior. The fin is most effective and sensitive when it is placed exactly above the step. A slight displacement of the fin in upstream of the step causes the complete change of flow and thermal behavior. Based on the obtained 2-D results it is interesting to investigate the side wall effect in three-dimensional simulations. The comparison of two-dimensional and three-dimensional numerical simulations with the available experimental results will be presented. Special attention has to be given to capture unsteadiness in the flow and thermal field.

State-of-charge estimation in lithium-ion batteries: A particle filter approach

NASA Astrophysics Data System (ADS)

Tulsyan, Aditya; Tsai, Yiting; Gopaluni, R. Bhushan; Braatz, Richard D.

2016-11-01

The dynamics of lithium-ion batteries are complex and are often approximated by models consisting of partial differential equations (PDEs) relating the internal ionic concentrations and potentials. The Pseudo two-dimensional model (P2D) is one model that performs sufficiently accurately under various operating conditions and battery chemistries. Despite its widespread use for prediction, this model is too complex for standard estimation and control applications. This article presents an original algorithm for state-of-charge estimation using the P2D model. Partial differential equations are discretized using implicit stable algorithms and reformulated into a nonlinear state-space model. This discrete, high-dimensional model (consisting of tens to hundreds of states) contains implicit, nonlinear algebraic equations. The uncertainty in the model is characterized by additive Gaussian noise. By exploiting the special structure of the pseudo two-dimensional model, a novel particle filter algorithm that sweeps in time and spatial coordinates independently is developed. This algorithm circumvents the degeneracy problems associated with high-dimensional state estimation and avoids the repetitive solution of implicit equations by defining a 'tether' particle. The approach is illustrated through extensive simulations.

Black holes, hidden symmetries, and complete integrability.

PubMed

Frolov, Valeri P; Krtouš, Pavel; Kubizňák, David

2017-01-01

The study of higher-dimensional black holes is a subject which has recently attracted vast interest. Perhaps one of the most surprising discoveries is a realization that the properties of higher-dimensional black holes with the spherical horizon topology and described by the Kerr-NUT-(A)dS metrics are very similar to the properties of the well known four-dimensional Kerr metric. This remarkable result stems from the existence of a single object called the principal tensor. In our review we discuss explicit and hidden symmetries of higher-dimensional Kerr-NUT-(A)dS black hole spacetimes. We start with discussion of the Killing and Killing-Yano objects representing explicit and hidden symmetries. We demonstrate that the principal tensor can be used as a "seed object" which generates all these symmetries. It determines the form of the geometry, as well as guarantees its remarkable properties, such as special algebraic type of the spacetime, complete integrability of geodesic motion, and separability of the Hamilton-Jacobi, Klein-Gordon, and Dirac equations. The review also contains a discussion of different applications of the developed formalism and its possible generalizations.

Real-time in situ three-dimensional integral videography and surgical navigation using augmented reality: a pilot study

PubMed Central

Suenaga, Hideyuki; Hoang Tran, Huy; Liao, Hongen; Masamune, Ken; Dohi, Takeyoshi; Hoshi, Kazuto; Mori, Yoshiyuki; Takato, Tsuyoshi

2013-01-01

To evaluate the feasibility and accuracy of a three-dimensional augmented reality system incorporating integral videography for imaging oral and maxillofacial regions, based on preoperative computed tomography data. Three-dimensional surface models of the jawbones, based on the computed tomography data, were used to create the integral videography images of a subject's maxillofacial area. The three-dimensional augmented reality system (integral videography display, computed tomography, a position tracker and a computer) was used to generate a three-dimensional overlay that was projected on the surgical site via a half-silvered mirror. Thereafter, a feasibility study was performed on a volunteer. The accuracy of this system was verified on a solid model while simulating bone resection. Positional registration was attained by identifying and tracking the patient/surgical instrument's position. Thus, integral videography images of jawbones, teeth and the surgical tool were superimposed in the correct position. Stereoscopic images viewed from various angles were accurately displayed. Change in the viewing angle did not negatively affect the surgeon's ability to simultaneously observe the three-dimensional images and the patient, without special glasses. The difference in three-dimensional position of each measuring point on the solid model and augmented reality navigation was almost negligible (<1 mm); this indicates that the system was highly accurate. This augmented reality system was highly accurate and effective for surgical navigation and for overlaying a three-dimensional computed tomography image on a patient's surgical area, enabling the surgeon to understand the positional relationship between the preoperative image and the actual surgical site, with the naked eye. PMID:23703710

Dynamic three-dimensional display of common congenital cardiac defects from reconstruction of two-dimensional echocardiographic images.

PubMed

Hsieh, K S; Lin, C C; Liu, W S; Chen, F L

1996-01-01

Two-dimensional echocardiography had long been a standard diagnostic modality for congenital heart disease. Further attempts of three-dimensional reconstruction using two-dimensional echocardiographic images to visualize stereotypic structure of cardiac lesions have been successful only recently. So far only very few studies have been done to display three-dimensional anatomy of the heart through two-dimensional image acquisition because such complex procedures were involved. This study introduced a recently developed image acquisition and processing system for dynamic three-dimensional visualization of various congenital cardiac lesions. From December 1994 to April 1995, 35 cases were selected in the Echo Laboratory here from about 3000 Echo examinations completed. Each image was acquired on-line with specially designed high resolution image grazmber with EKG and respiratory gating technique. Off-line image processing using a window-architectured interactive software package includes construction of 2-D ehcocardiographic pixel to 3-D "voxel" with conversion of orthogonal to rotatory axial system, interpolation, extraction of region of interest, segmentation, shading and, finally, 3D rendering. Three-dimensional anatomy of various congenital cardiac defects was shown, including four cases with ventricular septal defects, two cases with atrial septal defects, and two cases with aortic stenosis. Dynamic reconstruction of a "beating heart" is recorded as vedio tape with video interface. The potential application of 3D display of the reconstruction from 2D echocardiographic images for the diagnosis of various congenital heart defects has been shown. The 3D display was able to improve the diagnostic ability of echocardiography, and clear-cut display of the various congenital cardiac defects and vavular stenosis could be demonstrated. Reinforcement of current techniques will expand future application of 3D display of conventional 2D images.

Three-dimensional biometric study of palatine rugae in children with a mixed-model analysis: a 9-year longitudinal study.

PubMed

Kim, Hong-Kyun; Moon, Sung-Chul; Lee, Shin-Jae; Park, Young-Seok

2012-05-01

The palatine rugae have been suggested as stable reference points for superimposing 3-dimensional virtual models before and after orthodontic treatment. We investigated 3-dimensional changes in the palatine rugae of children over 9 years. Complete dental stone casts were biennially prepared for 56 subjects (42 girls, 14 boys) aged from 6 to 14 years. Using 3-dimensional laser scanning and reconstruction software, virtual casts were constructed. Medial and lateral points of the first anterior 3 rugae were defined as the 3-dimensional landmarks. The length of each ruga and the distance between the end points of the rugae were measured in virtual 3-dimensional space. The measurement changes over time were analyzed by using the mixed-effect method for longitudinal data. There were slight increases in the linear measurements in the rugae areas: the lengths of the rugae and the distances between them during the observation period. However, the amounts of the increments were relatively small when compared with the initial values and individual random variability. Although age affected the linear dimensions significantly, it was not clinically significant; the rugae were relatively stable. The use of the palatine rugae as reference points for superimposing and evaluating changes during orthodontic treatment was thought to be possible with special cautions. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Bayesian transformation cure frailty models with multivariate failure time data.

PubMed

Yin, Guosheng

2008-12-10

We propose a class of transformation cure frailty models to accommodate a survival fraction in multivariate failure time data. Established through a general power transformation, this family of cure frailty models includes the proportional hazards and the proportional odds modeling structures as two special cases. Within the Bayesian paradigm, we obtain the joint posterior distribution and the corresponding full conditional distributions of the model parameters for the implementation of Gibbs sampling. Model selection is based on the conditional predictive ordinate statistic and deviance information criterion. As an illustration, we apply the proposed method to a real data set from dentistry.

Couplings of gravitational currents with Chern-Simons gravities

NASA Astrophysics Data System (ADS)

Ertem, Ümit; Açık, Özgür

2013-02-01

The coupling of conserved p-brane currents with non-Abelian gauge theories is done consistently by using Chern-Simons forms. Conserved currents localized on p-branes that have a gravitational origin can be constructed from Killing-Yano forms of the underlying spacetime. We propose a generalization of the coupling procedure with Chern-Simons gravities to the case of gravitational conserved currents. In odd dimensions, the field equations of coupled Chern-Simons gravities that describe the local curvature on p-branes are obtained. In special cases of three and five dimensions, the field equations are investigated in detail.

Beating the odds--nothing is impossible, its just a road less traveled.

PubMed

Brady, Mike

2008-03-01

By contrasting students with learning disabilities and students with schizophrenia, it becomes conspicuously clear that they face many of the same hurdles. I know through personal experience because I have both. Postsecondary institutions are making great strides in balancing the scales for disabled students. Special education for learning-disabled students is more a hindrance than a benefit; mainstreaming many learning-disabled students seems a more appropriate option. Students need to take advantage of the services that are most beneficial to them. The least restrictive environment is predominantly, if not always, the correct choice.

Three-dimensional visualization and display technologies; Proceedings of the Meeting, Los Angeles, CA, Jan. 18-20, 1989

NASA Technical Reports Server (NTRS)

Robbins, Woodrow E. (Editor); Fisher, Scott S. (Editor)

1989-01-01

Special attention was given to problems of stereoscopic display devices, such as CAD for enhancement of the design process in visual arts, stereo-TV improvement of remote manipulator performance, a voice-controlled stereographic video camera system, and head-mounted displays and their low-cost design alternatives. Also discussed was a novel approach to chromostereoscopic microscopy, computer-generated barrier-strip autostereography and lenticular stereograms, and parallax barrier three-dimensional TV. Additional topics include processing and user interface isssues and visualization applications, including automated analysis and fliud flow topology, optical tomographic measusrements of mixing fluids, visualization of complex data, visualization environments, and visualization management systems.

Ray trace visualization of negative refraction of light in two-dimensional air-bridged silicon photonic crystal slabs at 1.55 microm.

PubMed

Gan, Lin; Liu, Ya-Zhao; Li, Jiang-Yan; Zhang, Ze-Bo; Zhang, Dao-Zhong; Li, Zhi-Yuan

2009-06-08

We demonstrate design, fabrication, and ray trace observation of negative refraction of near-infrared light in a two-dimensional square lattice of air holes etched into an air-bridged silicon slab. Special surface morphologies are designed to reduce the impedance mismatch when light refracts from a homogeneous silicon slab into the photonic crystal slab. We clearly observed negative refraction of infrared light for TE-like modes in a broad wavelength range by using scanning near-field optical microscopy technology. The experimental results are in good agreement with finite-difference time-domain simulations. The results indicate the designed photonic crystal structure can serve as polarization beam splitter.

Black Holes, Hidden Symmetry and Complete Integrability: Brief Review

NASA Astrophysics Data System (ADS)

Frolov, Valeri P.

This chapter contains a brief review of the remarkable properties of higher dimensional rotating black holes with the spherical topology of the horizon. We demonstrate that these properties are connected with and generated by a special geometrical object, the Principal Conformal Killing-Yano tensor (PCKYT). The most general solution, describing such black holes, Kerr-NUT-ADS metric, admits this structure. Moreover a solution of the Einstein Equations with (or without) a cosmological constant which possesses PCKYT is the Kerr-NUT-ADS metric. This object (PCKYT) is responsible for such remarkable properties of higher dimensional rotating black holes as: (i) complete integrability of geodesic equations and (ii) complete separation of variables of the important field equations.

Three-dimensional solutions of the magnetohydrostatic equations for rigidly rotating magnetospheres in cylindrical coordinates

NASA Astrophysics Data System (ADS)

Wilson, F.; Neukirch, T.

2018-01-01

We present new analytical three-dimensional solutions of the magnetohydrostatic equations, which are applicable to the co-rotating frame of reference outside a rigidly rotating cylindrical body, and have potential applications to planetary magnetospheres and stellar coronae. We consider the case with centrifugal force only, and use a transformation method in which the governing equation for the "pseudo-potential" (from which the magnetic field can be calculated) becomes the Laplace partial differential equation. The new solutions extend the set of previously found solutions to those of a "fractional multipole" nature, and offer wider possibilities for modelling than before. We consider some special cases, and present example solutions.

Real-Valued Covariance Vector Sparsity-Inducing DOA Estimation for Monostatic MIMO Radar

PubMed Central

Wang, Xianpeng; Wang, Wei; Li, Xin; Liu, Jing

2015-01-01

In this paper, a real-valued covariance vector sparsity-inducing method for direction of arrival (DOA) estimation is proposed in monostatic multiple-input multiple-output (MIMO) radar. Exploiting the special configuration of monostatic MIMO radar, low-dimensional real-valued received data can be obtained by using the reduced-dimensional transformation and unitary transformation technique. Then, based on the Khatri–Rao product, a real-valued sparse representation framework of the covariance vector is formulated to estimate DOA. Compared to the existing sparsity-inducing DOA estimation methods, the proposed method provides better angle estimation performance and lower computational complexity. Simulation results verify the effectiveness and advantage of the proposed method. PMID:26569241

Real-Valued Covariance Vector Sparsity-Inducing DOA Estimation for Monostatic MIMO Radar.

PubMed

Wang, Xianpeng; Wang, Wei; Li, Xin; Liu, Jing

2015-11-10

In this paper, a real-valued covariance vector sparsity-inducing method for direction of arrival (DOA) estimation is proposed in monostatic multiple-input multiple-output (MIMO) radar. Exploiting the special configuration of monostatic MIMO radar, low-dimensional real-valued received data can be obtained by using the reduced-dimensional transformation and unitary transformation technique. Then, based on the Khatri-Rao product, a real-valued sparse representation framework of the covariance vector is formulated to estimate DOA. Compared to the existing sparsity-inducing DOA estimation methods, the proposed method provides better angle estimation performance and lower computational complexity. Simulation results verify the effectiveness and advantage of the proposed method.

Pancharatnam-Berry phase and kinetic magnetoelectric effect in trigonal tellurium

NASA Astrophysics Data System (ADS)

Şahin, C.; Rou, J.; Ma, J.; Pesin, D. A.

2018-05-01

We study the kinetic magnetoelectric effect (current-induced magnetization including both the orbital and spin contributions) in three-dimensional conductors, specializing to the case of p -doped trigonal tellurium. We include both intrinsic and extrinsic contributions to the effect, which stem from the band structure of the crystal, and from disorder scattering, respectively. Specifically, we determine the dependence of the kinetic magnetoelectric response on the hole doping in tellurium, and show that the intrinsic and extrinsic effects dominate for low and high levels of doping, respectively. The results of this work imply that three-dimensional helical metals are promising for spintronics applications, in particular, they can provide robust control over current-induced magnetic torques.

Principal Killing strings in higher-dimensional Kerr-NUT-(A)dS spacetimes

NASA Astrophysics Data System (ADS)

Boos, Jens; Frolov, Valeri P.

2018-04-01

We construct special solutions of the Nambu-Goto equations for stationary strings in a general Kerr-NUT-(A)dS spacetime in any number of dimensions. This construction is based on the existence of explicit and hidden symmetries generated by the principal tensor which exists for these metrics. The characteristic property of these string configurations, which we call "principal Killing strings," is that they are stretched out from "infinity" to the horizon of the Kerr-NUT-(A)dS black hole and remain regular at the latter. We also demonstrate that principal Killing strings extract angular momentum from higher-dimensional rotating black holes and interpret this as the action of an asymptotic torque.

Maximum Torque and Momentum Envelopes for Reaction Wheel Arrays

NASA Technical Reports Server (NTRS)

Markley, F. Landis; Reynolds, Reid G.; Liu, Frank X.; Lebsock, Kenneth L.

2009-01-01

Spacecraft reaction wheel maneuvers are limited by the maximum torque and/or angular momentum that the wheels can provide. For an n-wheel configuration, the torque or momentum envelope can be obtained by projecting the n-dimensional hypercube, representing the domain boundary of individual wheel torques or momenta, into three dimensional space via the 3xn matrix of wheel axes. In this paper, the properties of the projected hypercube are discussed, and algorithms are proposed for determining this maximal torque or momentum envelope for general wheel configurations. Practical strategies for distributing a prescribed torque or momentum among the n wheels are presented, with special emphasis on configurations of four, five, and six wheels.

Recent advances in electrochemical biosensors based on graphene two-dimensional nanomaterials.

PubMed

Song, Yang; Luo, Yanan; Zhu, Chengzhou; Li, He; Du, Dan; Lin, Yuehe

2016-02-15

Graphene as a star among two-dimensional nanomaterials has attracted tremendous research interest in the field of electrochemistry due to their intrinsic properties, including the electronic, optical, and mechanical properties associated with their planar structure. The marriage of graphene and electrochemical biosensors has created many ingenious biosensing strategies for applications in the areas of clinical diagnosis and food safety. This review provides a comprehensive overview of the recent advances in the development of graphene based electrochemical biosensors. Special attention is paid to graphene-based enzyme biosensors, immunosensors, and DNA biosensors. Future perspectives on high-performance graphene-based electrochemical biosensors are also discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

Teacher Efficacy, Work Engagement, and Social Support Among Chinese Special Education School Teachers

PubMed Central

Minghui, Lu; Lei, Hao; Xiaomeng, Chen; Potměšilc, Miloň

2018-01-01

This paper investigates the relationship between teacher efficacy and socio-demographic factors, work engagement, and social support among Chinese special education school teachers. The sample comprised 1,027 special education school teachers in mainland China. The Teachers’ Sense of Efficacy Scale, the Multi-Dimensional Scale of Perceived Social Support, and the Utrecht Work Engagement Scale were used for data collection. Correlation analysis revealed that social support, work engagement, and teacher efficacy were significantly correlated with each other. Additionally, gender, years of experience, and monthly salary were significant predictors of teacher efficacy. Furthermore, structural equation modeling analysis showed that social support exerted its indirect effect on teacher efficacy through the mediation of work engagement. The findings of this study provide a new perspective on the complex association between social support and teacher efficacy. The explanations and limitations of these findings are discussed. PMID:29867634

Nonlinear stability of non-stationary cross-flow vortices in compressible boundary layers

NASA Technical Reports Server (NTRS)

Gajjar, J. S. B.

1995-01-01

The nonlinear evolution of long wavelength non-stationary cross-flow vortices in a compressible boundary layer is investigated and the work extends that of Gajjar (1994) to flows involving multiple critical layers. The basic flow profile considered in this paper is that appropriate for a fully three-dimensional boundary layer with O(1) Mach number and with wall heating or cooling. The governing equations for the evolution of the cross-flow vortex are obtained and some special cases are discussed. One special case includes linear theory where exact analytic expressions for the growth rate of the vortices are obtained. Another special case is a generalization of the Bassom & Gajjar (1988) results for neutral waves to compressible flows. The viscous correction to the growth rate is derived and it is shown how the unsteady nonlinear critical layer structure merges with that for a Haberman type of viscous critical layer.

Global Discrete Artificial Boundary Conditions for Time-Dependent Wave Propagation

NASA Technical Reports Server (NTRS)

Ryabenkii, V. S.; Tsynkov, S. V.; Turchaninov, V. I.; Bushnell, Dennis M. (Technical Monitor)

2001-01-01

We construct global artificial boundary conditions (ABCs) for the numerical simulation of wave processes on unbounded domains using a special non-deteriorating algorithm that has been developed previously for the long-term computation of wave-radiation solutions. The ABCs are obtained directly for the discrete formulation of the problem; in so doing, neither a rational approximation of 'non-reflecting kernels,' nor discretization of the continuous boundary conditions is required. The extent of temporal nonlocality of the new ABCs appears fixed and limited; in addition, the ABCs can handle artificial boundaries of irregular shape on regular grids with no fitting/adaptation needed and no accuracy loss induced. The non-deteriorating algorithm, which is the core of the new ABCs is inherently three-dimensional, it guarantees temporally uniform grid convergence of the solution driven by a continuously operating source on arbitrarily long time intervals, and provides unimprovable linear computational complexity with respect to the grid dimension. The algorithm is based on the presence of lacunae, i.e., aft fronts of the waves, in wave-type solutions in odd-dimension spaces, It can, in fact, be built as a modification on top of any consistent and stable finite-difference scheme, making its grid convergence uniform in time and at the same time keeping the rate of convergence the same as that of the non-modified scheme. In the paper, we delineate the construction of the global lacunae-based ABCs in the framework of a discretized wave equation. The ABCs are obtained for the most general formulation of the problem that involves radiation of waves by moving sources (e.g., radiation of acoustic waves by a maneuvering aircraft). We also present systematic numerical results that corroborate the theoretical design properties of the ABCs' algorithm.

Low Temperature Analysis of Correlation Functions of the Blume-Emery-Griffiths Model at the Antiquadrupolar-Disordered Interface

NASA Astrophysics Data System (ADS)

Lima, Paulo C.

2016-11-01

We show that at low temperatures the d dimensional Blume-Emery-Griffiths model in the antiquadrupolar-disordered interface has all its infinite volume correlation functions < prod _{iin A}σ _i^{n_i}rangle _{τ }, where Asubset Z^d is finite and sum _{iin A}n_i is odd, equal zero, regardless of the boundary condition τ . In particular, the magnetization < σ _irangle _{τ } is zero, for all τ . We also show that the infinite volume mean magnetization lim _{Λ → ∞}Big < 1/|Λ |sum _{iin Λ }σ _iBig rangle _{Λ ,τ } is zero, for all τ.

Act-and-wait time-delayed feedback control of autonomous systems

NASA Astrophysics Data System (ADS)

Pyragas, Viktoras; Pyragas, Kestutis

2018-02-01

Recently an act-and-wait modification of time-delayed feedback control has been proposed for the stabilization of unstable periodic orbits in nonautonomous dynamical systems (Pyragas and Pyragas, 2016 [30]). The modification implies a periodic switching of the feedback gain and makes the closed-loop system finite-dimensional. Here we extend this modification to autonomous systems. In order to keep constant the phase difference between the controlled orbit and the act-and-wait switching function an additional small-amplitude periodic perturbation is introduced. The algorithm can stabilize periodic orbits with an odd number of real unstable Floquet exponents using a simple single-input single-output constraint control.

Theoretical calculations of oxygen relaxation in YBa2Cu3O6+x ceramics

NASA Astrophysics Data System (ADS)

Mi, Y.; Schaller, R.; Sathish, S.; Benoit, W.

1991-12-01

A two-dimensional theoretical model of stress-induced point-defect relaxation in a layered structure is presented, with a detailed discussion of the special case of YBa2Cu3O6+x. The experimental results of oxygen relaxation in YBa2Cu3O6+x can be explained qualitatively by this model.

15 CFR Supplement No. 2 to Part 748 - Unique Application and Submission Requirements

Code of Federal Regulations, 2013 CFR

2013-01-01

... tools, dimensional inspection machines, direct numerical control systems, specially designed assemblies... Commerce Control List (§ 774.1 of the EAR)—see Category 5 Part 1 Notes 1 and 2 and Part 2 Note 1. License... containing computers to destinations in Country Group D:1 (See Supplement No. 1 to part 740 of the EAR), or...

15 CFR Supplement No. 2 to Part 748 - Unique Application and Submission Requirements

Code of Federal Regulations, 2010 CFR

2010-01-01

... tools, dimensional inspection machines, direct numerical control systems, specially designed assemblies... Commerce Control List (§ 774.1 of the EAR)—see Category 5 Part 1 Notes 1 and 2 and Part 2 Note 1. License... containing computers to destinations in Country Group D:1 (See Supplement No. 1 to part 740 of the EAR), or...

15 CFR Supplement No. 2 to Part 748 - Unique Application and Submission Requirements

Code of Federal Regulations, 2011 CFR

2011-01-01

... tools, dimensional inspection machines, direct numerical control systems, specially designed assemblies... Commerce Control List (§ 774.1 of the EAR)—see Category 5 Part 1 Notes 1 and 2 and Part 2 Note 1. License... containing computers to destinations in Country Group D:1 (See supplement No. 1 to part 740 of the EAR), or...

Comment on “Band gaps structure and semi-Dirac point of two-dimensional function photonic crystals” by Si-Qi Zhang et al.

NASA Astrophysics Data System (ADS)

Zhang, Hai-Feng

2018-01-01

Not Available Project supported by the Special Grade of the Financial Support from the China Postdoctoral Science Foundation (Grant No. 2016T90455), the China Postdoctoral Science Foundation (Grant No. 2015M581790), and the Chinese Jiangsu Planned Projects for Postdoctoral Research Funds, China (Grant No. 1501016A).

Phenomenological plasmon broadening and relation to the dispersion

NASA Astrophysics Data System (ADS)

Hobbiger, Raphael; Drachta, Jürgen T.; Kreil, Dominik; Böhm, Helga M.

2017-02-01

Pragmatic ways of including lifetime broadening of collective modes in the electron liquid are critically compared. Special focus lies on the impact of the damping parameter onto the dispersion. It is quantitatively exemplified for the two-dimensional case, for both, the charge ('sheet'-)plasmon and the spin-density plasmon. The predicted deviations fall within the resolution limits of advanced techniques.

Confronting Dilemmas Posed by Three-Dimensional Classroom Assessment: Introduction to a Virtual Issue of "Science Education"

ERIC Educational Resources Information Center

Furtak, Erin Marie

2017-01-01

Wide-scale adoption of the "Next Generation Science Standards" has raised new challenges for classroom teachers as they learn not only how to engage students in this new vision of science learning, but also how to assess students' engagement in that learning. This paper introduces a virtual special issue of "Science Education"…

Starspot detection and properties

NASA Astrophysics Data System (ADS)

Savanov, I. S.

2013-07-01

I review the currently available techniques for the starspots detection including the one-dimensional spot modelling of photometric light curves. Special attention will be paid to the modelling of photospheric activity based on the high-precision light curves obtained with space missions MOST, CoRoT, and Kepler. Physical spot parameters (temperature, sizes and variability time scales including short-term activity cycles) are discussed.

Unbiased nonorthogonal bases for tomographic reconstruction

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

Sainz, Isabel; Klimov, Andrei B.; Roa, Luis

2010-05-15

We have developed a general method for constructing a set of nonorthogonal bases with equal separations between all different basis states in prime dimensions. The results are that the corresponding biorthogonal counterparts are pairwise unbiased with the components of the original bases. Using these bases, we derive an explicit expression for the optimal tomography in nonorthogonal bases. A special two-dimensional case is analyzed separately.

Commercial enteral formulas and nutrition support teams improve the outcome of home enteral tube feeding.

PubMed

Klek, Stanislaw; Szybinski, Piotr; Sierzega, Marek; Szczepanek, Kinga; Sumlet, Magdalena; Kupiec, Monika; Koczur-Szozda, Elzbieta; Steinhoff-Nowak, Malgorzata; Figula, Krzysztof; Kowalczyk, Tomasz; Kulig, Jan

2011-05-01

The benefits of home enteral tube feeding (HETF) provided by nutrition support teams (NSTs) have been questioned recently, given the growing costs to the healthcare system. This study examined the effect of a specialized home enteral nutrition program on clinical outcome variables in HETF patients. The observational study included 203 patients (103 women, 100 men; mean age 52.5 years) receiving HETF with homemade diets for at least 12 months before starting a specialized home nutrition program for another 12 months consisting of provision of commercial enteral formulas and the guidance of an NST. Both study periods were compared regarding the number of hospital admissions, length of hospital and intensive care unit (ICU) stay, and costs of hospitalization. A specialized HETF program significantly reduced the number of hospital admissions and the duration of hospital and ICU stays. The need for hospitalization and ICU admission was significantly reduced, with odds ratios of 0.083 (95% confidence interval, 0.051-0.133, P < .001) and 0.259 (95% confidence interval, 0.124-0.539, P < .001), respectively. Specialized HETF was associated with a significant decrease in the prevalence of pneumonia (24.1% vs 14.2%), respiratory failure (7.3% vs 1.9%), urinary tract infection (11.3% vs 4.9%), and anemia (3.9% vs 0%) requiring hospitalization. The average yearly cost of hospital treatment decreased from $764.65 per patient to $142.66 per year per patient. The specialized HETF care program reduces morbidity and costs related to long-term enteral feeding at home.

Five Factor Model personality disorder scales: An introduction to a special section on assessment of maladaptive variants of the five factor model.

PubMed

Bagby, R Michael; Widiger, Thomas A

2018-01-01

The Five-Factor Model (FFM) is a dimensional model of general personality structure, consisting of the domains of neuroticism (or emotional instability), extraversion versus introversion, openness (or unconventionality), agreeableness versus antagonism, and conscientiousness (or constraint). The FFM is arguably the most commonly researched dimensional model of general personality structure. However, a notable limitation of existing measures of the FFM has been a lack of coverage of its maladaptive variants. A series of self-report inventories has been developed to assess for the maladaptive personality traits that define Diagnostic and Statistical Manual of Mental Disorders (fifth edition; DSM-5) Section II personality disorders (American Psychiatric Association [APA], 2013) from the perspective of the FFM. In this paper, we provide an introduction to this Special Section, presenting the rationale and empirical support for these measures and placing them in the historical context of the recent revision to the APA diagnostic manual. This introduction is followed by 5 papers that provide further empirical support for these measures and address current issues within the personality assessment literature. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Hyperfine structure measurements of neutral iodine atom (127I) using Fourier Transform Spectrometry

NASA Astrophysics Data System (ADS)

Ashok, Chilukoti; Vishwakarma, S. R.; Bhatt, Himal; Ankush, B. K.; Deo, M. N.

2018-01-01

We report the hyperfine Structure (hfs) splitting observations of neutral iodine atom (II) in the 6000 - 10,000 cm-1 near infrared spectral region. The measurements were carried out using a high-resolution Fourier Transform Spectrometer (FTS), where an electrodeless discharge lamp (EDL), excited using microwaves, was employed as the light source and InGaAs as the light detector. A specially designed setup was used to lower the plasma temperature of the medium so as to reduce the Doppler width and consequently to increase the spectral resolution of hfs components. A total of 183 lines with hfs splitting have been observed, out of which hfs in 53 spectral lines are reported for the first time. On the basis of hfs analysis, we derived the magnetic dipole and electric quadrupole coupling constants, A and B respectively for 30 even and 30 odd energy levels and are compared with the values available in the literature. New hfs values for 5 even and 4 odd levels are also reported here for the first time.

Comprehensive two-dimensional liquid chromatography for polyphenol analysis in foodstuffs.

PubMed

Cacciola, Francesco; Farnetti, Sara; Dugo, Paola; Marriott, Philip John; Mondello, Luigi

2017-01-01

Polyphenols are a class of plant secondary metabolites that are recently drawing a special interest because of their broad spectrum of pharmacological effects. As they are characterized by an enormous structural variability, the identification of these molecules in food samples is a difficult task, and sometimes having only a limited number of commercially available reference materials is not of great help. One-dimensional liquid chromatography is the most widely applied analytical approach for their analysis. In particular, the hyphenation of liquid chromatography to mass spectrometry has come to play an influential role by allowing relatively fast tentative identification and accurate quantification of polyphenolic compounds at trace levels in vegetable media. However, when dealing with very complex real-world food samples, a single separation system often does not provide sufficient resolving power for attaining rewarding results. Comprehensive two-dimensional liquid chromatography is a technique of great analytical impact, since it offers much higher peak capacities than separations in a single dimension. In the present review, we describe applications in the field of comprehensive two-dimensional liquid chromatography for polyphenol analysis in real-world food samples. Comprehensive two-dimensional liquid chromatography applications to nonfood matrices fall outside the scope of the current report and will not be discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

SUSY’s Ladder: Reframing sequestering at Large Volume

DOE PAGES

Reece, Matthew; Xue, Wei

2016-04-07

Theories with approximate no-scale structure, such as the Large Volume Scenario, have a distinctive hierarchy of multiple mass scales in between TeV gaugino masses and the Planck scale, which we call SUSY's Ladder. This is a particular realization of Split Supersymmetry in which the same small parameter suppresses gaugino masses relative to scalar soft masses, scalar soft masses relative to the gravitino mass, and the UV cutoff or string scale relative to the Planck scale. This scenario has many phenomenologically interesting properties, and can avoid dangers including the gravitino problem, flavor problems, and the moduli-induced LSP problem that plague othermore » supersymmetric theories. We study SUSY's Ladder using a superspace formalism that makes the mysterious cancelations in previous computations manifest. This opens the possibility of a consistent effective field theory understanding of the phenomenology of these scenarios, based on power-counting in the small ratio of string to Planck scales. We also show that four-dimensional theories with approximate no-scale structure enforced by a single volume modulus arise only from two special higher-dimensional theories: five-dimensional supergravity and ten-dimensional type IIB supergravity. As a result, this gives a phenomenological argument in favor of ten dimensional ultraviolet physics which is different from standard arguments based on the consistency of superstring theory.« less

5D Super Yang-Mills on Y p, q Sasaki-Einstein Manifolds

NASA Astrophysics Data System (ADS)

Qiu, Jian; Zabzine, Maxim

2015-01-01

On any simply connected Sasaki-Einstein five dimensional manifold one can construct a super Yang-Mills theory which preserves at least two supersymmetries. We study the special case of toric Sasaki-Einstein manifolds known as Y p, q manifolds. We use the localisation technique to compute the full perturbative part of the partition function. The full equivariant result is expressed in terms of a certain special function which appears to be a curious generalisation of the triple sine function. As an application of our general result we study the large N behaviour for the case of single hypermultiplet in adjoint representation and we derive the N 3-behaviour in this case.

Cloud and Radiation Mission with Active and Passive Sensing from the Space Station

NASA Technical Reports Server (NTRS)

Spinhirne, James D.

1998-01-01

A cloud and aerosol radiative forcing and physical process study involving active laser and radar profiling with a combination of passive radiometric sounders and imagers would use the space station as an observation platform. The objectives are to observe the full three dimensional cloud and aerosol structure and the associated physical parameters leading to a complete measurement of radiation forcing processes. The instruments would include specialized radar and lidar for cloud and aerosol profiling, visible, infrared and microwave imaging radiometers with comprehensive channels for cloud and aerosol observation and specialized sounders. The low altitude,. available power and servicing capability of the space station are significant advantages for the active sensors and multiple passive instruments.

A simple and inexpensive on-column frit fabrication method for fused-silica capillaries for increased capacity and versatility in LC-MS/MS applications.

PubMed

Wang, Ling-Chi; Okitsu, Cindy Yen; Kochounian, Harold; Rodriguez, Anthony; Hsieh, Chih-Lin; Zandi, Ebrahim

2008-05-01

A modified sol-gel method for a one-step on-column frit preparation for fused-silica capillaries and its utility for peptide separation in LC-MS/MS is described. This method is inexpensive, reproducible, and does not require specialized equipments. Because the frit fabrication process does not damage polyimide coating, the frit-fabricated column can be tightly connected on-line for high pressure LC. These columns can replace any capillary liquid transfer tubing without any specialized connections up-stream of a spray tip column. Therefore multiple columns with different phases can be connected in series for one- or multiple-dimensional chromatography.

3D refractive index measurements of special optical fibers

NASA Astrophysics Data System (ADS)

Yan, Cheng; Huang, Su-Juan; Miao, Zhuang; Chang, Zheng; Zeng, Jun-Zhang; Wang, Ting-Yun

2016-09-01

A digital holographic microscopic chromatography-based approach with considerably improved accuracy, simplified configuration and performance stability is proposed to measure three dimensional refractive index of special optical fibers. Based on the approach, a measurement system is established incorporating a modified Mach-Zehnder interferometer and lab-developed supporting software for data processing. In the system, a phase projection distribution of an optical fiber is utilized to obtain an optimal digital hologram recorded by a CCD, and then an angular spectrum theory-based algorithm is adopted to extract the phase distribution information of an object wave. The rotation of the optic fiber enables the experimental measurements of multi-angle phase information. Based on the filtered back projection algorithm, a 3D refraction index of the optical fiber is thus obtained at high accuracy. To evaluate the proposed approach, both PANDA fibers and special elliptical optical fiber are considered in the system. The results measured in PANDA fibers agree well with those measured using S14 Refractive Index Profiler, which is, however, not suitable for measuring the property of a special elliptical fiber.

Care coordination for children with special health care needs: a cohort study.

PubMed

Zanello, Elisa; Calugi, Simona; Sanders, Lee M; Lenzi, Jacopo; Faldella, Giacomo; Rucci, Paola; Fantini, Maria Pia

2017-02-03

Care coordination is widely recognized as a key element of care for patients with chronic and complex medical conditions and their families. In care for children with special health care needs the Family Pediatrician (FP) plays a central role as care coordinator. This study aims to evaluate the FPs' activities of care coordination for children with special health care needs in the pediatric primary care setting, using an on-line measurement tool. Within the prospective cohort study SpeNK (Special Needs Kids), newborns and children with special health care needs were recruited at discharge from three hospital facilities in Bologna province, from October 1st 2012 to September 30th 2014. Their FPs were invited to complete a questionnaire (SpeNK-FP) at each encounter for the patient during a 9-month period after hospital discharge. SpeNK-FP was developed by adapting the Care Coordination Measurement Tool (CCMT©) developed by Antonelli et al., to the Italian organizational context. The outcome of interest, derived from the questionnaire, is inappropriate use of services. Forty FPs completed assessments for 49 children at each of 382 clinical encounters. The majority of children (71.4%) had special health care needs, without complicating social issues. FPs reported "no need for care coordination" in 50.8% of the encounters and 41.1% of records about patient needs requiring care coordination. The most common activity implemented to meet children's needs was telephone contact with a medical provider. According to FPs, 80% of encounters prevented inappropriate services use. In multivariate regression, pediatric-specialist contact (telephone or in person) was associated with reduced odds of physician report of preventable hospitalization (OR = 0.06, 95% CI 0.01-0.42, p = 0.005). The study shows the potential for FPs in Italy to serve as care coordinators and facilitate the implementation of integrated care pathways for children with special health care needs.

Social anxiety disorder and social fears in the Canadian military: prevalence, comorbidity, impairment, and treatment-seeking.

PubMed

Mather, Amber A; Stein, Murray B; Sareen, Jitender

2010-10-01

Military mental health research has rarely investigated social anxiety disorder, despite its known serious consequences in the general population, and what work has been conducted has used specialized samples (e.g., veterans) not representative of all military personnel. Data were from the 2002 Canadian Community Health Survey-Canadian Forces Supplement, a representative survey of 8441 active regular and reserve military personnel. Social anxiety disorder has a high lifetime (8.2%) and past-year (3.2%) prevalence in the military. It is associated with increased odds of depression, panic attacks/disorder, generalized anxiety disorder, and post-traumatic stress disorder (AOR range 4.16-16.29). Being female, ages 35-44, or separated/divorced/widowed increases the odds of having social anxiety disorder, while being an officer or a reservist decreases the odds. Treatment-seeking, as in the general population, is relatively rare. Overall, military personnel with social anxiety disorder experience significant rates of role impairment in all domains (53.1-88.3% report some impairment), with the rate of role impairment increasing with the number of social fears. Notably, many (70.6%) report at least some impairment at work (i.e., in their job with the military). Social anxiety disorder is an important disorder to take into account when considering military mental health. Observing low rates of treatment-seeking for social anxiety disorder among military personnel highlights the importance of initiatives to allow its identification and treatment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Physician characteristics and prescription drug use during pregnancy: a population-based study.

PubMed

Weng, Sung-Shun; Chen, Yi-Hua; Lin, Ching-Chun; Keller, Joseph J; Wang, I-Te; Lin, Herng-Ching

2013-02-01

We aimed to explore the relationship between physician characteristics and their prescribing behavior regarding category D and X drugs for pregnant women by using a population-based data set in Taiwan. The sampled population for the study included 14,430 women. These women received a total of 198,420 prescriptions during pregnancy. We performed multivariate logistic regression analysis by using generalized estimated equations to assess the odds ratio (OR) of the prescription for categories D and X drugs among doctors after adjusting for maternal age and chronic disease. Of the total 198,420 prescriptions, 4.2% were prescribed category D and X drugs. The covariate-adjusted odds for physicians aged between 40 and 49 years and 50 and 59 years for prescribing category D and X drugs to pregnant women were 1.22 (95% confidence interval [95% CI], 1.15-1.31) and 1.51 (95% CI, 1.40-1.64) times that of physicians aged between 30 and 39 years, respectively. Male physicians were less likely to prescribe category D and X drugs to pregnant women than female physicians (OR, 0.69; 95% CI, 0.63-0.75). In addition, physicians specializing in "other" specialties were more likely (OR, 1.46; 95% CI, 1.41-1.54) to prescribe category D and X drugs compared with those specializing in obstetrics/gynecology, whereas physicians practicing in central Taiwan were less likely (OR, 0.85; 95% CI, 0.80-0.89) than their counterparts in other regions of Taiwan to prescribe category D and X drugs. We conclude that physician characteristics, including sex, age, specialty, and practice location, were associated with the prescription of category D and X drugs for pregnant women. Copyright © 2013 Elsevier Inc. All rights reserved.

Neonatal Morbidity at Term, Early Child Development, and School Performance: A Population Study.

PubMed

Bentley, Jason P; Schneuer, Francisco J; Lain, Samantha J; Martin, Andrew J; Gordon, Adrienne; Nassar, Natasha

2018-02-01

Investigate the association between severe neonatal morbidity (SNM) and child development and school performance among term infants. The study population included term infants without major congenital conditions born between 2000 and 2007 in New South Wales, Australia, with a linked record of developmental assessment at ages 4 to 6 years in 2009 or 2012 ( n = 144 535) or school performance at ages 7 to 9 years from 2009 to 2014 ( n = 253 447). Developmental outcomes included special needs or being vulnerable and/or at risk in 1 of 5 developmental domains. School performance outcomes were test exemption, or performing <-1 SD on reading or numeracy tests. Binary generalized estimating equations were used to estimate associations between SNM and outcomes, adjusting for sociodemographic, perinatal, and assessment and/or test characteristics. Overall, 2.1% of infants experienced SNM. The adjusted odds ratio (95% confidence interval) for SNM and physical health was 1.18 (1.08-1.29), 1.14 (1.02-1.26) for language and cognitive skills, and 1.14 (1.06-1.24) and 1.13 (1.05-1.21) for scoring <-1 SD in reading and numeracy, respectively. SNM was most strongly associated with special needs 1.34 (1.15-1.55) and test exemption 1.50 (1.25-1.81). SNM infants born at 37 to 38 weeks' gestation and who were small for gestational age had the greatest likelihood of poorer outcomes. Term infants with SNM have greater odds of poor neurodevelopment in childhood. These findings provide population-based information for families and can inform clinical counseling and guidelines for follow-up and early intervention. Copyright © 2018 by the American Academy of Pediatrics.

Prevalence of physical activity, screen time, and obesity among US children by the service type of special health care needs.

PubMed

Kim, Juhee; Greaney, Mary L

2014-07-01

Children with special health care needs (SHCN) may be at greater risk of obesity than children without SHCN. A new classification system categorizes SHCN among children by service type using the following categories: No-SHCN, medication use only, services use only, medication + service use, and functional limitations. Research is needed to examine obesity and obesity-related behaviors among children using the new classification system. To determine the prevalence of inadequate vigorous physical activity (VPA), high screen time and obesity by SHCN category using the new classification system. Multivariate regression models were fitted for inadequate VPA, high screen time, and obesity to determine if there were differences in these outcomes by SHCN category, adjusting for multistage-sampling and survey-design effects using a nationally representative sample of children in the National Survey of Children's Health 2007. 22.9% of the sample was classified as having SHCN: 9% medication use only, 5% medication + service use, 4% service use only, and 5% functional limitations. Children in the medication use only and medication + service use groups were not at increased risk for inadequate VPA, high screen time, or obesity. Children in the service use only and functional limitation groups had increased odds of high screen time and obesity, which disappeared after controlling for confounders. However, the higher odds of inadequate VPA remained significant in the service use only [OR (95% CI) = 2.00 (1.34-3.00)] and the functional limitations groups with 2.21 (1.55-3.15). Physical activity promotion programs are needed for children with SHCN, especially children with functional limitations and those who require service use only and do not use prescribed medication. Copyright © 2014 Elsevier Inc. All rights reserved.

Student threat assessment as a standard school safety practice: Results from a statewide implementation study.

PubMed

Cornell, Dewey; Maeng, Jennifer L; Burnette, Anna Grace; Jia, Yuane; Huang, Francis; Konold, Timothy; Datta, Pooja; Malone, Marisa; Meyer, Patrick

2018-06-01

Threat assessment has been widely endorsed as a school safety practice, but there is little research on its implementation. In 2013, Virginia became the first state to mandate student threat assessment in its public schools. The purpose of this study was to examine the statewide implementation of threat assessment and to identify how threat assessment teams distinguish serious from nonserious threats. The sample consisted of 1,865 threat assessment cases reported by 785 elementary, middle, and high schools. Students ranged from pre-K to Grade 12, including 74.4% male, 34.6% receiving special education services, 51.2% White, 30.2% Black, 6.8% Hispanic, and 2.7% Asian. Survey data were collected from school-based teams to measure student demographics, threat characteristics, and assessment results. Logistic regression indicated that threat assessment teams were more likely to identify a threat as serious if it was made by a student above the elementary grades (odds ratio 0.57; 95% lower and upper bound 0.42-0.78), a student receiving special education services (1.27; 1.00-1.60), involved battery (1.61; 1.20-2.15), homicide (1.40; 1.07-1.82), or weapon possession (4.41; 2.80-6.96), or targeted an administrator (3.55; 1.73-7.30). Student race and gender were not significantly associated with a serious threat determination. The odds ratio that a student would attempt to carry out a threat classified as serious was 12.48 (5.15-30.22). These results provide new information on the nature and prevalence of threats in schools using threat assessment that can guide further work to develop this emerging school safety practice. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Is Annual Volume Enough? The Role of Experience and Specialization on Inpatient Mortality After Hepatectomy.

PubMed

Hashimoto, Daniel A; Bababekov, Yanik J; Mehtsun, Winta T; Stapleton, Sahael M; Warshaw, Andrew L; Lillemoe, Keith D; Chang, David C; Vagefi, Parsia A

2017-10-01

To investigate the effect of subspecialty practice and experience on the relationship between annual volume and inpatient mortality after hepatic resection. The impact of annual surgical volume on postoperative outcomes has been extensively examined. However, the impact of cumulative surgeon experience and specialty training on this relationship warrants investigation. The New York Statewide Planning and Research Cooperative System inpatient database was queried for patients' ≥18 years who underwent wedge hepatectomy or lobectomy from 2000 to 2014. Primary exposures included annual surgeon volume, surgeon experience (early vs late career), and surgical specialization-categorized as general surgery (GS), surgical oncology (SO), and transplant (TS). Primary endpoint was inpatient mortality. Hierarchical logistic regression was performed accounting for correlation at the level of the surgeon and the hospital, and adjusting for patient demographics, comorbidities, presence of cirrhosis, and annual surgical hospital volume. A total of 13,467 cases were analyzed. Overall inpatient mortality was 2.35%. On unadjusted analysis, late career surgeons had a mortality rate of 2.62% versus 1.97% for early career surgeons. GS had a mortality rate of 2.98% compared with 1.68% for SO and 2.67% for TS. Once risk-adjusted, annual volume was associated with reduced mortality only among early-career surgeons (odds ratio 0.82, P = 0.001) and general surgeons (odds ratio 0.65, P = 0.002). No volume effect was seen among late-career or specialty-trained surgeons. Annual volume alone likely contributes only a partial assessment of the volume-outcome relationship. In patients undergoing hepatic resection, increased annual volume did not confer a mortality benefit on subspecialty surgeons or late career surgeons.

Associations Between Peer Counseling and Breastfeeding Initiation and Duration: An Analysis of Minnesota Participants in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).

PubMed

McCoy, Marcia Burton; Geppert, Joni; Dech, Linda; Richardson, Michaela

2018-01-01

Background Peer counseling (PC) has been associated with increased breastfeeding initiation and duration, but few analyses have examined the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) model for peer counseling or the continuation of breastfeeding from birth through 12 months postpartum. Objectives Identify associations between Minnesota WIC Peer Breastfeeding Support Program services and breastfeeding initiation and continuation. Methods Retrospective analysis of observational data from the Minnesota WIC program's administrative database of women who gave birth in 2012 and accepted a PC program referral prenatally (n = 2219). Multivariate logistic regression and Cox regression models examined associations between peer services and breastfeeding initiation and continuation of any breastfeeding. Results Among women who accepted referral into a PC program, odds of initiation were significantly higher among those who received peer services (Odds Ratio (OR): 1.66; 95% CI 1.19-2.32), after adjusting for confounders. Women who received peer services had a significantly lower hazard of breastfeeding discontinuation from birth through 12 months postpartum than women who did not receive services. (Hazard Ratio (HR) month one: 0.45; 95% CI 0.33-0.61; months two through twelve: 0.33; 95% CI 0.18-0.60). The effect of peer counseling did not differ significantly by race and ethnicity, taking into account mother's country of origin. Conclusion for practice Receipt of peer services was positively associated with breastfeeding initiation and continued breastfeeding from birth through 12 months postpartum. Making peer services available to more women, especially in communities with low initiation and duration, could improve maternal and child health in Minnesota.

The German version of the Child Behavior Checklist 1.5-5 to identify children with a risk of autism spectrum disorder.

PubMed

Limberg, Katharina; Gruber, Karolin; Noterdaeme, Michele

2017-04-01

A long delay between the first registered symptoms of autism spectrum disorder and a final diagnosis has been reported. The reasons for this are the spare use of specialized autism instruments, missing clinical expertise, and the late referral to specialized centers in primary care. Previous studies recommending the Child Behavior Checklist 1.5-5 for screening have requested additional research. A total of 183 children aged 25-71 months participated in this study. The Child Behavior Checklist scales of 80 children with autism spectrum disorder were compared with 103 children diagnosed with other psychiatric disorders. In the logistic regression analysis, the Withdrawn and Pervasive Developmental Problems Child Behavior Checklist scales with a significant predictive value of risk for an autism spectrum disorder diagnosis were identified. The optimal cutoff points T = 64.5 on the Pervasive Developmental Problems scale (area under the curve = 0.781, sensitivity = 0.83, specificity = 0.60, positive predictive value = 0.62, negative predictive value = 0.82, odds ratio = 7) and T = 60.5 on the Withdrawn scale (area under the curve = 0.809, sensitivity = 0.88, specificity = 0.63, positive predictive value = 0.65, negative predictive value = 0.87, odds ratio = 12) were evaluated in the receiver operating characteristics analysis. The present study confirms the utility of the German version of the Child Behavior Checklist 1.5-5 as a level 1 screening tool to identify children with a risk of autism spectrum disorder; however, a risk of over-identifying should be considered. The Child Behavior Checklist 1.5-5 can complement the pediatric examination as a quick and cost-effective questionnaire.

The prevalence and determinants of overweight and obesity among French youths and adults with intellectual disabilities attending special education schools.

PubMed

Bégarie, Jérôme; Maïano, Christophe; Leconte, Pascale; Ninot, Grégory

2013-05-01

This study examines the prevalence of overweight and obesity and a panel of potential determinants among French youths and adults with an intellectual disability (ID). The sample used consisted of 1120 youths and adults with an ID, from 5 to 28 years old, attending a French special education school. The results indicated that 19.8% of the participants with an ID are classified as overweight and 8.6% as obese. Multivariate logistic regression analyses revealed that there are nearly three times more girls/women classified as overweight than boys/men. Additionally, they showed that there are nearly two times more participants from southern France classified as overweight than from northern France, and that the risk of being classified as overweight significantly increases with seniority in the school. Next, the interaction effects observed indicated first that there are nearly two times more boys/men on psychotropic medication classified as overweight than boys/men not on psychotropic medication. Second, they revealed that the odds of being classified as overweight for boys/men not on psychotropic medication are 47% lower than for girls/women not on psychotropic medication. Third, they indicated that there are nearly two times more boys/men from southern France classified as obese than boys/men from northern France. Fourth, they showed that the odds of being classified as obese for boys/men from northern France are 52% lower than for girls/women from northern France. In conclusion, these results should be viewed as preliminary and need to be replicated since, to our knowledge, this study is the first one to examine this topic while simultaneously controlling for all of the potential determinants and relying on a sample of youths and adults. Copyright © 2013 Elsevier Ltd. All rights reserved.

Parallax scanning methods for stereoscopic three-dimensional imaging

NASA Astrophysics Data System (ADS)

Mayhew, Christopher A.; Mayhew, Craig M.

2012-03-01

Under certain circumstances, conventional stereoscopic imagery is subject to being misinterpreted. Stereo perception created from two static horizontally separated views can create a "cut out" 2D appearance for objects at various planes of depth. The subject volume looks three-dimensional, but the objects themselves appear flat. This is especially true if the images are captured using small disparities. One potential explanation for this effect is that, although three-dimensional perception comes primarily from binocular vision, a human's gaze (the direction and orientation of a person's eyes with respect to their environment) and head motion also contribute additional sub-process information. The absence of this information may be the reason that certain stereoscopic imagery appears "odd" and unrealistic. Another contributing factor may be the absence of vertical disparity information in a traditional stereoscopy display. Recently, Parallax Scanning technologies have been introduced, which provide (1) a scanning methodology, (2) incorporate vertical disparity, and (3) produce stereo images with substantially smaller disparities than the human interocular distances.1 To test whether these three features would improve the realism and reduce the cardboard cutout effect of stereo images, we have applied Parallax Scanning (PS) technologies to commercial stereoscopic digital cinema productions and have tested the results with a panel of stereo experts. These informal experiments show that the addition of PS information into the left and right image capture improves the overall perception of three-dimensionality for most viewers. Parallax scanning significantly increases the set of tools available for 3D storytelling while at the same time presenting imagery that is easy and pleasant to view.

A comparison of two- and three-dimensional stochastic models of regional solute movement

USGS Publications Warehouse

Shapiro, A.M.; Cvetkovic, V.D.

1990-01-01

Recent models of solute movement in porous media that are based on a stochastic description of the porous medium properties have been dedicated primarily to a three-dimensional interpretation of solute movement. In many practical problems, however, it is more convenient and consistent with measuring techniques to consider flow and solute transport as an areal, two-dimensional phenomenon. The physics of solute movement, however, is dependent on the three-dimensional heterogeneity in the formation. A comparison of two- and three-dimensional stochastic interpretations of solute movement in a porous medium having a statistically isotropic hydraulic conductivity field is investigated. To provide an equitable comparison between the two- and three-dimensional analyses, the stochastic properties of the transmissivity are defined in terms of the stochastic properties of the hydraulic conductivity. The variance of the transmissivity is shown to be significantly reduced in comparison to that of the hydraulic conductivity, and the transmissivity is spatially correlated over larger distances. These factors influence the two-dimensional interpretations of solute movement by underestimating the longitudinal and transverse growth of the solute plume in comparison to its description as a three-dimensional phenomenon. Although this analysis is based on small perturbation approximations and the special case of a statistically isotropic hydraulic conductivity field, it casts doubt on the use of a stochastic interpretation of the transmissivity in describing regional scale movement. However, by assuming the transmissivity to be the vertical integration of the hydraulic conductivity field at a given position, the stochastic properties of the hydraulic conductivity can be estimated from the stochastic properties of the transmissivity and applied to obtain a more accurate interpretation of solute movement. ?? 1990 Kluwer Academic Publishers.

The Frontal View of the Nose: Lighting Effects and Photographic Bias.

PubMed

Strub, Benedikt; Mende, Konrad; Meuli-Simmen, Claudia; Bessler, Stephan

2015-07-01

Most aesthetic rhinosurgeons rely on proper photographic documentation of the nose using several different views. The frontal view is probably the most important, but it is also the most demanding. In the frontal view, delicate, 3-dimensional (3D) anatomic structures require special photographic skills. Lighting is crucial for detail rendition and 3D reproduction of the nose, and for apparent photographic bias. We compared the quality of reproduction and photographic bias with different symmetric and asymmetric lighting in common clinical practice described in the literature. The photographs were compared for anatomic reproduction, shadowing, 3-dimensionality, and apparent changes of nasal shape (bias). Symmetric lighting did not satisfy the demands of the rhinosurgeons because of marginal 3-dimensionality, reduced detail rendition, or photographic bias. Strongly asymmetric lighting altered the nasal shape adversely for bias depending on the side of illumination, but led to very good 3-dimensionality. Slightly asymmetric lighting demonstrated the best results for detail rendition and 3-dimensionality. Classic symmetric quarter light is a practicable lighting technique with limitations in the rendition of detail and 3-dimensionality. Slightly asymmetric lighting offered a perfect compromise, with substantially improved detail rendition and 3-dimensionality. Strongly asymmetric lighting may lead to photographic bias depending on the side of illumination. Frontal documentation of the nose with asymmetric lighting should, therefore, always be performed in duplicate, with asymmetric lighting from the right side and from the left side, to prevent misleading interpretations. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Biological Response to the Dynamic Spectral-Polarized Underwater Light Field

DTIC Science & Technology

2009-01-01

Station phone: (831) 655-6219 fax: (831) 375 -0793 email: lignje@stanford.edu George W. Kattawar Department of Physics Texas A & M...temperature sensors plus 3-dimensional accelerometers (all sampled at 1 Hz , Figure 8). Videos revealed squid fickering display that is visually similar to...include anti- submarine warfare, special operations, clandestine reconnaissance, and harbor security operations. RELATED PROJECTS The CCNY group

Evaluation of a School-to-Work Internship Pilot Program for High School Seniors with Special Needs

ERIC Educational Resources Information Center

Goldstein, David S.

2012-01-01

Students with disabilities face a variety of challenges that extend beyond the classroom, as they are often behind their peers in social and life skills. As they exit their secondary education programs they are often ill prepared to meet the multi-dimensional demands of the work place. According to the United States Department of Labor (2011),…

The Story in the Mind: The Effect of 3D Gameplay on the Structuring of Written L2 Narratives

ERIC Educational Resources Information Center

Neville, David O.

2015-01-01

The article reports on a mixed-methods study evaluating the use of a three-dimensional digital game-based language learning (3D-DGBLL) environment to teach German two-way prepositions and specialized vocabulary within a simulated real-world context of German recycling and waste management systems. The study assumed that goal-directed player…

A Study of Transparent Plastics for use on Aircraft, Special Report

NASA Technical Reports Server (NTRS)

Axilrod, Benjamin M.; Kline, Gordon M.

1937-01-01

Various transparent organic plastics, including both commercially available and experimental materials, have been examined to determine their suitability for use as flexible windshields on aircraft, The properties which have been studied include light transmission, haziness, distortion, resistance to weathering, scratch and indentation hardness, impact strength, dimensional stability, resistance to water and various cleaning fluids, bursting strength at normal and low temperatures, and flammability.

Peierls instability as the insulating origin of the Na/Si(111)-(3 × 1) surface with a Na coverage of 2/3 monolayers

NASA Astrophysics Data System (ADS)

Kang, Myung Ho; Kwon, Se Gab; Jung, Sung Chul

2018-03-01

Density functional theory (DFT) calculations are used to investigate the insulating origin of the Na/Si(111)-(3 × 1) surface with a Na coverage of 2/3 monolayers. In the coverage definition, one monolayer refers to one Na atom per surface Si atom, so this surface contains an odd number of electrons (i.e., three Si dangling-bond electrons plus two Na electrons) per 3 × 1 unit cell. Interestingly, this odd-electron surface has been ascribed to a Mott-Hubbard insulator to account for the measured insulating band structure with a gap of about 0.8 eV. Here, we instead propose a Peierls instability as the origin of the experimental band gap. The concept of Peierls instability is fundamental in one-dimensional metal systems but has not been taken into account in previous studies of this surface. Our DFT calculations demonstrate that the linear chain structure of Si dangling bonds in this surface is energetically unstable with respect to a × 2 buckling modulation, and the buckling-induced band gap of 0.79 eV explains well the measured insulating nature.

Finite Deformation of Magnetoelastic Film

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

Barham, Matthew Ian

2011-05-31

A nonlinear two-dimensional theory is developed for thin magnetoelastic lms capable of large deformations. This is derived directly from three-dimensional theory. Signi cant simpli cations emerge in the descent from three dimensions to two, permitting the self eld generated by the body to be computed a posteriori. The model is specialized to isotropic elastomers with two material models. First weak magnetization is investigated leading to a free energy where magnetization and deformation are un-coupled. The second closely couples the magnetization and deformation. Numerical solutions are obtained to equilibrium boundary-value problems in which the membrane is subjected to lateral pressure andmore » an applied magnetic eld. An instability is inferred and investigated for the weak magnetization material model.« less

Benchtop fabrication of three-dimensional reconfigurable microfluidic devices from paper-polymer composite.

PubMed

Han, Yu Long; Wang, Wenqi; Hu, Jie; Huang, Guoyou; Wang, Shuqi; Lee, Won Gu; Lu, Tian Jian; Xu, Feng

2013-12-21

We presented a benchtop technique that can fabricate reconfigurable, three-dimensional (3D) microfluidic devices made from a soft paper-polymer composite. This fabrication approach can produce microchannels at a minimal width of 100 μm and can be used to prototype 3D microfluidic devices by simple bending and stretching. The entire fabrication process can be finished in 2 hours on a laboratory bench without the need for special equipment involved in lithography. Various functional microfluidic devices (e.g., droplet generator and reconfigurable electronic circuit) were prepared using this paper-polymer hybrid microfluidic system. The developed method can be applied in a wide range of standard applications and emerging technologies such as liquid-phase electronics.

The numerical study of the coextrusion process of polymer melts in the cable head

NASA Astrophysics Data System (ADS)

Kozitsyna, M. V.; Trufanova, N. M.

2017-06-01

The process of coextrusion consists in a simultaneous creation of all necessary insulating layers of different polymers in the channel of a special forming tool. The main focus of this study is the analysis of technological, geometrical and rheological characteristics on the values of the layer’s thickness. In this paper are considered three geometries of cable head on the three-dimensional and two-dimensional representation. The mathematical models of separate and joint flow of polymer melts have been implemented by the finite element method in Ansys software package. The velocity fields, temperature, pressure in the cross-sections of the channel and by the length have been obtained. The influence of some thickness characteristics of insulation layers has been identified.

The Newport Button: The Large Scale Replication Of Combined Three-And Two-Dimensional Holographic Images

NASA Astrophysics Data System (ADS)

Cowan, James J.

1984-05-01

A unique type of holographic imagery and its large scale replication are described. The "Newport Button", which was designed as an advertising premium item for the Newport Corporation, incorporates a complex overlay of holographic diffraction gratings surrounding a three-dimensional holographic image of a real object. The combined pattern is recorded onto a photosensitive medium from which a metal master is made. The master is subsequently used to repeatedly emboss the pattern into a thin plastic sheet. Individual patterns are then die cut from the metallized plastic and mounted onto buttons. A discussion is given of the diffraction efficiencies of holograms made in this particular fashion and of the special requirements of the replication process.

Two-dimensional numerical model for the high electron mobility transistor

NASA Astrophysics Data System (ADS)

Loret, Dany

1987-11-01

A two-dimensional numerical drift-diffusion model for the High Electron Mobility Transistor (HEMT) is presented. Special attention is paid to the modeling of the current flow over the heterojunction. A finite difference scheme is used to solve the equations, and a variable mesh spacing was implemented to cope with the strong variations of functions near the heterojunction. Simulation results are compared to experimental data for a 0.7 μm gate length device. Small-signal transconductances and cut-off frequency obtained from the 2-D model agree well with the experimental values from S-parameter measurements. It is shown that the numerical models give good insight into device behaviour, including important parasitic effects such as electron injection into the bulk GaAs.

Scattering of three-dimensional plane waves in a self-reinforced half-space lying over a triclinic half-space

NASA Astrophysics Data System (ADS)

Gupta, Shishir; Pramanik, Abhijit; Smita; Pramanik, Snehamoy

2018-06-01

The phenomenon of plane waves at the intersecting plane of a triclinic half-space and a self-reinforced half-space is discussed with possible applications during wave propagation. Analytical expressions of the phase velocities of reflection and refraction for quasi-compressional and quasi-shear waves under initial stress are discussed carefully. The closest form of amplitude proportions on reflection and refraction factors of three quasi-plane waves are developed mathematically by applying appropriate boundary conditions. Graphics are sketched to exhibit the consequences of initial stress in the three-dimensional plane wave on reflection and refraction coefficients. Some special cases that coincide with the fundamental properties of several layers are designed to express the reflection and refraction coefficients.

Newly-Developed 3D GRMHD Code and its Application to Jet Formation

NASA Technical Reports Server (NTRS)

Mizuno, Y.; Nishikawa, K.-I.; Koide, S.; Hardee, P.; Fishman, G. J.

2006-01-01

We have developed a new three-dimensional general relativistic magnetohydrodynamic code by using a conservative, high-resolution shock-capturing scheme. The numerical fluxes are calculated using the HLL approximate Riemann solver scheme. The flux-interpolated constrained transport scheme is used to maintain a divergence-free magnetic field. We have performed various 1-dimensional test problems in both special and general relativity by using several reconstruction methods and found that the new 3D GRMHD code shows substantial improvements over our previous model. The . preliminary results show the jet formations from a geometrically thin accretion disk near a non-rotating and a rotating black hole. We will discuss the jet properties depended on the rotation of a black hole and the magnetic field strength.

Orbital effect for the Fulde-Ferrell-Larkin-Ovchinnikov phase in a quasi-two-dimensional superconductor in a parallel magnetic field

NASA Astrophysics Data System (ADS)

Lebed, A. G.

2018-04-01

We theoretically study the orbital destructive effect against superconductivity in a parallel magnetic field in the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO or LOFF) phase at zero temperature in a quasi-two-dimensional (Q2D) conductor. We demonstrate that at zero temperature a special parameter, λ =l⊥(H ) /d , is responsible for strength of the orbital effect, where l⊥(H ) is a typical "size" of the quasiclassical electron orbit in a magnetic field and d is the interplane distance. We discuss applications of our results to the existing experiments on the FFLO phase in the organic Q2D conductors κ -(ET) 2Cu (NCS) 2 and κ -(ET) 2Cu [N (CN) 2] Cl .

Two-dimensional MoTe2 materials: From synthesis, identification, and charge transport to electronics applications

NASA Astrophysics Data System (ADS)

Chang, Yuan-Ming; Lin, Che-Yi; Lin, Yen-Fu; Tsukagoshi, Kazuhito

2016-11-01

We present a review of recent developments in the synthesis, thickness identification, electronic properties, and possible applications of layered MoTe2 flakes. Special emphasis is made on two-dimensional (2D) MoTe2 semiconductors and the extensive research in recent years on their applications in electronics. Layered MoTe2 flakes have been the focus of substantial interest in the research community because of their fascinating characteristics, including an appropriate band gap and a simple fabrication method (exfoliation) to form layered nanomaterials. Our aim is to provide the readers an overview of layered MoTe2 flakes and to understand their properties, which may lead to their applications in micro- and nanoelectronics.

Three-dimensional aspects of radiative transfer in remote sensing of precipitation: Application to the 1986 COHMEX storm

NASA Technical Reports Server (NTRS)

Haferman, J. L.; Krajewski, W. F.; Smith, T. F.

1994-01-01

Several multifrequency techniques for passive microwave estimation of precipitation based on the absorption and scattering properties of hydrometers have been proposed in the literature. In the present study, plane-parallel limitations are overcome by using a model based on the discrete-ordinates method to solve the radiative transfer equation in three-dimensional rectangular domains. This effectively accounts for the complexity and variety of radiation problems encountered in the atmosphere. This investigation presents result for plane-parallel and three-dimensional radiative transfer for a precipitating system, discusses differences between these results, and suggests possible explanations for these differences. Microphysical properties were obtained from the Colorado State University Regional Atmospehric Modeling System and represent a hailstorm observed during the 1986 Cooperative Huntsville Meteorological Experiment. These properties are used as input to a three-dimensional radiative transfer model in order to simulate satellite observation of the storm. The model output consists of upwelling brightness temperatures at several of the frequencies on the Special Sensor Microwave/Imager. The radiative transfer model accounts for scattering and emission of atmospheric gases and hydrometers in liquid and ice phases. Brightness temperatures obtained from the three-dimensional model of this investigation indicate that horizontal inhomogeneities give rise to brightness temperature fields that can be quite different from fields obtained using plane-parallel radiative transfer theory. These differences are examined for various resolutions of the satellite sensor field of view. In adddition, the issue of boundary conditions for three-dimensional atmospheric radiative transfer is addressed.

Determination of statistics for any rotation of axes of a bivariate normal elliptical distribution. [of wind vector components

NASA Technical Reports Server (NTRS)

Falls, L. W.; Crutcher, H. L.

1976-01-01

Transformation of statistics from a dimensional set to another dimensional set involves linear functions of the original set of statistics. Similarly, linear functions will transform statistics within a dimensional set such that the new statistics are relevant to a new set of coordinate axes. A restricted case of the latter is the rotation of axes in a coordinate system involving any two correlated random variables. A special case is the transformation for horizontal wind distributions. Wind statistics are usually provided in terms of wind speed and direction (measured clockwise from north) or in east-west and north-south components. A direct application of this technique allows the determination of appropriate wind statistics parallel and normal to any preselected flight path of a space vehicle. Among the constraints for launching space vehicles are critical values selected from the distribution of the expected winds parallel to and normal to the flight path. These procedures are applied to space vehicle launches at Cape Kennedy, Florida.

One-dimensional dielectric bi-periodic photonic structures based on ternary photonic crystals

NASA Astrophysics Data System (ADS)

Dadoenkova, Nataliya N.; Dadoenkova, Yuliya S.; Panyaev, Ivan S.; Sannikov, Dmitry G.; Lyubchanskii, Igor L.

2018-01-01

We investigate the transmittivity spectra, fields, and energy distribution of the electromagnetic eigenwaves propagating in a one-dimensional (1D) dielectric photonic crystal [(TiO2/SiO2)NAl2O3]M with two periods formed by unit cells TiO2/SiO2 and (TiO2/SiO2)NAl2O3. Spectra of TE- and TM-modes depend on the geometric parameters of the structure and undergo modifications with the change in the period numbers, layer thicknesses, and incidence angle. Special attention is paid to the applicability of the hybrid effective medium approximation comprising the long-wave approximation and two-dimensional (2 × 2) transfer matrix method. We demonstrate spectral peculiarities of the bi-periodic structure and also show the differences between the band gap spectra of the bi-periodic and ternary 1D dielectric photonic crystals. The presented photonic crystal structure can find its applications in optoelectronics and nanophotonics areas as omnidirectional reflectors, optical ultra-narrow bandpass filters, and antireflection coatings.

Three-Dimensional Bioprinting: Toward the Era of Manufacturing Human Organs as Spare Parts for Healthcare and Medicine^.

PubMed

Mir, Tanveer Ahmad; Nakamura, Makoto

2017-06-01

Three-dimensional (3D) printing technology has been used in industrial worlds for decades. Three-dimensional bioprinting has recently received an increasing attention across the globe among researchers, academicians, students, and even the ordinary people. This emerging technique has a great potential to engineer highly organized functional bioconstructs with complex geometries and tailored components for engineering bioartificial tissues/organs for widespread applications, including transplantation, therapeutic investigation, drug development, bioassay, and disease modeling. Although many specialized 3D printers have been developed and applied to print various types of 3D tissue constructs, bioprinting technologies still have several technical challenges, including high resolution distribution of cells, controlled deposition of bioinks, suitable bioink materials, maturation of cells, and effective vascularization and innervation within engineered complex structures. In this brief review, we discuss about bioprinting approach, current limitations, and possibility of future advancements for producing engineered bioconstructs and bioartificial organs with desired functionalities.

Classification and identification of reading and math disabilities: the special case of comorbidity.

PubMed

Branum-Martin, Lee; Fletcher, Jack M; Stuebing, Karla K

2013-01-01

Much of learning disabilities research relies on categorical classification frameworks that use psychometric tests and cut points to identify children with reading or math difficulties. However, there is increasing evidence that the attributes of reading and math learning disabilities are dimensional, representing correlated continua of severity. We discuss issues related to categorical and dimensional approaches to reading and math disabilities, and their comorbid associations, highlighting problems with the use of cut points and correlated assessments. Two simulations are provided in which the correlational structure of a set of cognitive and achievement data are simulated from a single population with no categorical structures. The simulations produce profiles remarkably similar to reported profile differences, suggesting that the patterns are a product of the cut point and the correlational structure of the data. If dimensional approaches better fit the attributes of learning disability, new conceptualizations and better methods to identification and intervention may emerge, especially for comorbid associations of reading and math difficulties.

Effective dimensional reduction algorithm for eigenvalue problems for thin elastic structures: A paradigm in three dimensions

PubMed Central

Ovtchinnikov, Evgueni E.; Xanthis, Leonidas S.

2000-01-01

We present a methodology for the efficient numerical solution of eigenvalue problems of full three-dimensional elasticity for thin elastic structures, such as shells, plates and rods of arbitrary geometry, discretized by the finite element method. Such problems are solved by iterative methods, which, however, are known to suffer from slow convergence or even convergence failure, when the thickness is small. In this paper we show an effective way of resolving this difficulty by invoking a special preconditioning technique associated with the effective dimensional reduction algorithm (EDRA). As an example, we present an algorithm for computing the minimal eigenvalue of a thin elastic plate and we show both theoretically and numerically that it is robust with respect to both the thickness and discretization parameters, i.e. the convergence does not deteriorate with diminishing thickness or mesh refinement. This robustness is sine qua non for the efficient computation of large-scale eigenvalue problems for thin elastic structures. PMID:10655469

Acoustic scattering by arbitrary distributions of disjoint, homogeneous cylinders or spheres.

PubMed

Hesford, Andrew J; Astheimer, Jeffrey P; Waag, Robert C

2010-05-01

A T-matrix formulation is presented to compute acoustic scattering from arbitrary, disjoint distributions of cylinders or spheres, each with arbitrary, uniform acoustic properties. The generalized approach exploits the similarities in these scattering problems to present a single system of equations that is easily specialized to cylindrical or spherical scatterers. By employing field expansions based on orthogonal harmonic functions, continuity of pressure and normal particle velocity are directly enforced at each scatterer using diagonal, analytic expressions to eliminate the need for integral equations. The effect of a cylinder or sphere that encloses all other scatterers is simulated with an outer iterative procedure that decouples the inner-object solution from the effect of the enclosing object to improve computational efficiency when interactions among the interior objects are significant. Numerical results establish the validity and efficiency of the outer iteration procedure for nested objects. Two- and three-dimensional methods that employ this outer iteration are used to measure and characterize the accuracy of two-dimensional approximations to three-dimensional scattering of elevation-focused beams.

Vertex Operators, Grassmannians, and Hilbert Schemes

NASA Astrophysics Data System (ADS)

Carlsson, Erik

2010-12-01

We approximate the infinite Grassmannian by finite-dimensional cutoffs, and define a family of fermionic vertex operators as the limit of geometric correspondences on the equivariant cohomology groups, with respect to a one-dimensional torus action. We prove that in the localization basis, these are the well-known fermionic vertex operators on the infinite wedge representation. Furthermore, the boson-fermion correspondence, locality, and intertwining properties with the Virasoro algebra are the limits of relations on the finite-dimensional cutoff spaces, which are true for geometric reasons. We then show that these operators are also, almost by definition, the vertex operators defined by Okounkov and the author in Carlsson and Okounkov ( http://arXiv.org/abs/0801.2565v2 [math.AG], 2009), on the equivariant cohomology groups of the Hilbert scheme of points on {mathbb C^2} , with respect to a special torus action.

Fully automated measuring setup for tactile coordinate measuring machine for three dimensional measurement of freeform eyeglass frames

NASA Astrophysics Data System (ADS)

Rückwardt, M.; Göpfert, A.; Correns, M.; Schellhorn, M.; Linß, G.

2010-07-01

Coordinate measuring machines are high precession all-rounder in three dimensional measuring. Therefore the versatility of parameters and expandability of additionally hardware is very comprehensive. Consequently you need much expert knowledge of the user and mostly a lot of advanced information about the measuring object. In this paper a coordinate measuring machine and a specialized measuring machine are compared at the example of the measuring of eyeglass frames. For this case of three dimensional measuring challenges the main focus is divided into metrological and economical aspects. At first there is shown a fully automated method for tactile measuring of this abstract form. At second there is shown a comparison of the metrological characteristics of a coordinate measuring machine and a tracer for eyeglass frames. The result is in favour to the coordinate measuring machine. It was not surprising in these aspects. At last there is shown a comparison of the machine in front of the economical aspects.

Dynamic analysis of geometrically non-linear three-dimensional beams under moving mass

NASA Astrophysics Data System (ADS)

Zupan, E.; Zupan, D.

2018-01-01

In this paper, we present a coupled dynamic analysis of a moving particle on a deformable three-dimensional frame. The presented numerical model is capable of considering arbitrary curved and twisted initial geometry of the beam and takes into account geometric non-linearity of the structure. Coupled with dynamic equations of the structure, the equations of moving particle are solved. The moving particle represents the dynamic load and varies the mass distribution of the structure and at the same time its path is adapting due to deformability of the structure. A coupled geometrically non-linear behaviour of beam and particle is studied. The equation of motion of the particle is added to the system of the beam dynamic equations and an additional unknown representing the coordinate of the curvilinear path of the particle is introduced. The specially designed finite-element formulation of the three-dimensional beam based on the weak form of consistency conditions is employed where only the boundary conditions are affected by the contact forces.

Three dimensional culture of the murine osteoblastic cell line OCT-1 on collagen coated microcarriers

NASA Astrophysics Data System (ADS)

Lau, P.; Hellweg, C. E.; Kirchner, S.; Baumstark-Khan, C.

2005-08-01

During long-term space missions, astronauts suffer from the loss of minerals especially from weightbearing bones due to prolonged sojourn under microgravity. Bone loss during space flight is about 1-2% per month. Bone is continually being remodelled under the influence of three types of highly specialized cells. Osteoblasts, the bone forming cells, osteoclasts, the bone resorbing cells and finally osteocytes preserve the homeostasis of bone formation and resorption. In vitro 3- dimensional cell culture of osteoblastic cell lines on microcarrier beads might be a better model to evaluate changes in bone cell morphology, function and differentiation under influence of spaceflight related factors than the conventional 2-D monolayer culture technique. Furthermore, it allows production of a greater amount of cells compared to the monolayer culture. Aim of this study is to examine the effects of culturing the immortalized murine osteoblastic cell line OCT-1 in a 3- dimensional environment on cell morphology and proliferation rate.

Functional Human Podocytes Generated in Organoids from Amniotic Fluid Stem Cells

PubMed Central

Benedetti, Valentina; Novelli, Rubina; Abbate, Mauro; Rizzo, Paola; Conti, Sara; Tomasoni, Susanna; Corna, Daniela; Pozzobon, Michela; Cavallotti, Daniela; Yokoo, Takashi; Morigi, Marina; Benigni, Ariela; Remuzzi, Giuseppe

2016-01-01

Generating kidney organoids using human stem cells could offer promising prospects for research and therapeutic purposes. However, no cell-based strategy has generated nephrons displaying an intact three-dimensional epithelial filtering barrier. Here, we generated organoids using murine embryonic kidney cells, and documented that these tissues recapitulated the complex three-dimensional filtering structure of glomerular slits in vivo and accomplished selective glomerular filtration and tubular reabsorption. Exploiting this technology, we mixed human amniotic fluid stem cells with mouse embryonic kidney cells to establish three-dimensional chimeric organoids that engrafted in vivo and grew to form vascularized glomeruli and tubular structures. Human cells contributed to the formation of glomerular structures, differentiated into podocytes with slit diaphragms, and internalized exogenously infused BSA, thus attaining in vivo degrees of specialization and function unprecedented for donor stem cells. In conclusion, human amniotic fluid stem cell chimeric organoids may offer new paths for studying renal development and human podocyte disease, and for facilitating drug discovery and translational research. PMID:26516208

A hybrid model of laser energy deposition for multi-dimensional simulations of plasmas and metals

NASA Astrophysics Data System (ADS)

Basko, Mikhail M.; Tsygvintsev, Ilia P.

2017-05-01

The hybrid model of laser energy deposition is a combination of the geometrical-optics ray-tracing method with the one-dimensional (1D) solution of the Helmholtz wave equation in regions where the geometrical optics becomes inapplicable. We propose an improved version of this model, where a new physically consistent criterion for transition to the 1D wave optics is derived, and a special rescaling procedure of the wave-optics deposition profile is introduced. The model is intended for applications in large-scale two- and three-dimensional hydrodynamic codes. Comparison with exact 1D solutions demonstrates that it can fairly accurately reproduce the absorption fraction in both the s- and p-polarizations on arbitrarily steep density gradients, provided that a sufficiently accurate algorithm for gradient evaluation is used. The accuracy of the model becomes questionable for long laser pulses simulated on too fine grids, where the hydrodynamic self-focusing instability strongly manifests itself.

Two-Dimensional Hermite Filters Simplify the Description of High-Order Statistics of Natural Images.

PubMed

Hu, Qin; Victor, Jonathan D

2016-09-01

Natural image statistics play a crucial role in shaping biological visual systems, understanding their function and design principles, and designing effective computer-vision algorithms. High-order statistics are critical for conveying local features, but they are challenging to study - largely because their number and variety is large. Here, via the use of two-dimensional Hermite (TDH) functions, we identify a covert symmetry in high-order statistics of natural images that simplifies this task. This emerges from the structure of TDH functions, which are an orthogonal set of functions that are organized into a hierarchy of ranks. Specifically, we find that the shape (skewness and kurtosis) of the distribution of filter coefficients depends only on the projection of the function onto a 1-dimensional subspace specific to each rank. The characterization of natural image statistics provided by TDH filter coefficients reflects both their phase and amplitude structure, and we suggest an intuitive interpretation for the special subspace within each rank.