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1

Electrophysiological Evidence of Mediolateral Functional Dichotomy in the Rat Accumbens during Cocaine Self-Administration  

PubMed Central

Given the increasing research emphasis on putative accumbal functional compartmentation, we sought to determine whether neurons that demonstrate changes in tonic firing rate during cocaine self-administration are differentially distributed across subregions of the NAcc. Rats were implanted with jugular catheters and microwire arrays targeting NAcc subregions (Core, Dorsal Shell, Ventromedial Shell, Ventrolateral Shell, Rostral Pole Shell). Recordings were obtained after acquisition of stable cocaine self-administration (0.77 mg/kg/0.2mL infusion; fixed-ratio 1 schedule of reinforcement; 6 hour daily sessions). During the self-administration phase of the experiment, neurons demonstrated either: 1) tonic suppression (or decrease), 2) tonic activation (or increase) or 3) no tonic change in firing rate with respect to rates of firing during pre- and post-drug phases. Consistent with earlier observations, tonic decrease was the predominant firing pattern observed. Differences in the prevalence of tonic increase firing were observed between the core and the dorsal shell and dorsal shell-core border regions, with the latter two areas exhibiting a virtual absence of tonic increases. Tonic suppression was exhibited to a greater extent by the dorsal shell-core border region relative to the core. These differences could reflect distinct subregional afferent processing and/or differential sensitivity of subpopulations of NAcc neurons to cocaine. Ventrolateral Shell firing topographies resembled those of core neurons. Taken together, these observations are consistent with an emerging body of literature that differentiates the accumbens mediolaterally and further advances the likelihood that distinct functions are subserved by NAcc subregions in appetitive processing. PMID:20092580

Fabbricatore, Anthony T.; Ghitza, Udi E.; Prokopenko, Volodymyr F.; West, Mark O.

2010-01-01

2

Dichotomy of functional organization in the mouse auditory cortex  

PubMed Central

The sensory areas of the cerebral cortex possess multiple topographic representations of sensory dimensions. Gradient of frequency selectivity (tonotopy) is the dominant organizational feature in the primary auditory cortex, while other feature-based organizations are less well established. We probed the topographic organization of the mouse auditory cortex at the single cell level using in vivo two-photon Ca2+ imaging. Tonotopy was present on a large scale but was fractured on a fine scale. Intensity tuning, important in level-invariant representation, was observed in individual cells but was not topographically organized. The presence or near-absence of putative sub-threshold responses revealed a dichotomy in topographic organization. Inclusion of sub-threshold responses revealed a topographic clustering of neurons with similar response properties, while such clustering was absent in supra-threshold responses. This dichotomy indicates that groups of nearby neurons with locally shared inputs can perform independent parallel computations in ACX. PMID:20118924

Bandyopadhyay, Sharba; Shamma, Shihab A.; Kanold, Patrick O.

2010-01-01

3

Beurling regular variation, Bloom dichotomy, and the Goab-Schinzel functional equation  

E-print Network

[Pet] and [Moh] ­cf. [BinO6]) of the Wiener Tauberian Theorem, studies functions f with f(x + tBeurling regular variation, Bloom dichotomy, and the Go÷¾ab-Schinzel functional equation by A. J. Ostaszewski To Anatole Beck on his 83rd birthday. Abstract. The class of `self-neglecting'functions

Haase, Markus

4

The dappled nature of causes of psychiatric illness: replacing the organic–functional/hardware–software dichotomy with empirically based pluralism  

PubMed Central

Our tendency to see the world of psychiatric illness in dichotomous and opposing terms has three major sources: the philosophy of Descartes, the state of neuropathology in late nineteenth century Europe (when disorders were divided into those with and without demonstrable pathology and labeled, respectively, organic and functional), and the influential concept of computer functionalism wherein the computer is viewed as a model for the human mind–brain system (brain = hardware, mind = software). These mutually re-enforcing dichotomies, which have had a pernicious influence on our field, make a clear prediction about how ‘difference-makers’ (aka causal risk factors) for psychiatric disorders should be distributed in nature. In particular, are psychiatric disorders like our laptops, which when they dysfunction, can be cleanly divided into those with software versus hardware problems? I propose 11 categories of difference-makers for psychiatric illness from molecular genetics through culture and review their distribution in schizophrenia, major depression and alcohol dependence. In no case do these distributions resemble that predicted by the organic–functional/hardware–software dichotomy. Instead, the causes of psychiatric illness are dappled, distributed widely across multiple categories. We should abandon Cartesian and computer-functionalism-based dichotomies as scientifically inadequate and an impediment to our ability to integrate the diverse information about psychiatric illness our research has produced. Empirically based pluralism provides a rigorous but dappled view of the etiology of psychiatric illness. Critically, it is based not on how we wish the world to be but how the difference-makers for psychiatric illness are in fact distributed. PMID:22230881

Kendler, KS

2012-01-01

5

Synaptic Mechanisms Underlying Functional Dichotomy between Intrinsic-Bursting and Regular-Spiking Neurons in Auditory Cortical Layer 5  

PubMed Central

Corticofugal projections from the primary auditory cortex (A1) have been shown to play a role in modulating subcortical processing. However, functional properties of the corticofugal neurons and their synaptic circuitry mechanisms remain unclear. In this study, we performed in vivo whole-cell recordings from layer 5 (L5) pyramidal neurons in the rat A1 and found two distinct neuronal classes according to their functional properties. Intrinsic-bursting (IB) neurons, the L5 corticofugal neurons, exhibited early and rather unselective spike responses to a wide range of frequencies. The exceptionally broad spectral tuning of IB neurons was attributable to their broad excitatory inputs with long temporal durations and inhibitory inputs being more narrowly tuned than excitatory inputs. This uncommon pattern of excitatory–inhibitory interplay was attributed initially to a broad thalamocortical convergence onto IB neurons, which also receive temporally prolonged intracortical excitatory input as well as feedforward inhibitory input at least partially from more narrowly tuned fast-spiking inhibitory neurons. In contrast, regular-spiking neurons, which are mainly corticocortical, exhibited sharp frequency tuning similar to L4 pyramidal cells, underlying which are well-matched purely intracortical excitation and inhibition. The functional dichotomy among L5 pyramidal neurons suggests two distinct processing streams. The spectrally and temporally broad synaptic integration in IB neurons may ensure robust feedback signals to facilitate subcortical function and plasticity in a general manner. PMID:23516297

Sun, Yujiao J.; Kim, Young-Joo; Ibrahim, Leena A.; Tao, Huizhong W.; Zhang, Li I.

2013-01-01

6

Age Effects on Mediolateral Balance Control  

PubMed Central

Background Age-related balance impairments, particularly in mediolateral direction (ML) may cause falls. Sufficiently sensitive and reliable ML balance tests are, however, lacking. This study is aimed to determine (1) the effect of age on and (2) the reliability of ML balance performance using Center of Mass (CoM) tracking. Methods Balance performance of 19 young (26±3 years) and 19 older (72±5 years) adults on ML-CoM tracking tasks was compared. Subjects tracked predictable and unpredictable target displacements at increasing frequencies with their CoM by shifting their weight sideward. Phase-shift (response delay) and gain (amplitude difference) between the CoM and target in the frequency domain were used to quantify performance. Thirteen older and all young adults were reassessed to determine reliability of balance performance measures. In addition, all older adults performed a series of clinical balance tests and conventional posturography was done in a sub-sample. Results Phase-shift and gain dropped below pre-determined thresholds (?90 degrees and 0.5) at lower frequencies in the older adults and were even lower below these frequencies than in young adults. Performance measures showed good to excellent reliability in both groups. All clinical scores were close to the maximum and no age effect was found using posturography. ML balance performance measures exhibited small but systematic between-session differences indicative of learning. Conclusions The ability to accurately perform ML-CoM tracking deteriorates with age. ML-CoM tracking tasks form a reliable tool to assess ML balance in young and older adults and are more sensitive to age-related impairment than posturography and clinical tests. PMID:25350846

Cofré Lizama, L. Eduardo; Pijnappels, Mirjam; Faber, Gert H.; Reeves, Peter N.; Verschueren, Sabine M.; van Dieën, Jaap H.

2014-01-01

7

Evidence for Two Distinct Stellar Initial Mass Functions: Probing for Clues to the Dichotomy  

NASA Astrophysics Data System (ADS)

We present new measurements of the velocity dispersions of 11 Local Group globular clusters using spatially integrated spectra, to expand our sample of clusters with precise integrated-light velocity dispersions to 29, over 4 different host galaxies. This sample allows us to further our investigation of the stellar mass function among clusters, with a particular emphasis on a search for the driver of the apparent bimodal nature of the inferred stellar initial mass function (IMF). We confirm our previous result that clusters fall into two classes. If, as we argue, this behavior reflects a variation in the stellar IMF, the cause of that variation is not clear. The variations do not correlate with formation epoch as quantified by age, metallicity quantified by [Fe/H], host galaxy, or internal structure as quantified by velocity dispersion, physical size, relaxation time, or luminosity. The stellar mass-to-light ratios, Upsilon*, of the high and low Upsilon* cluster populations are well-matched to those found in recent studies of early and late type galaxies, respectively.

Zaritsky, Dennis; Colucci, Janet E.; Pessev, Peter M.; Bernstein, Rebecca A.; Chandar, Rupali

2014-12-01

8

The Danger of False Dichotomies.  

ERIC Educational Resources Information Center

Responds to an article that examined 10 dichotomies in teacher education (SP 527 128), suggesting that too much time and energy are spent debating false dichotomies and addressing two specific dichotomies (preservice versus inservice and campus versus school site). Recommends that professional educators pool their energy and collaborate (rather…

LaBoskey, Vicky Kubler

1998-01-01

9

Implications of increased medio-lateral trunk sway for ambulatory mechanics  

Microsoft Academic Search

The purposes of this study was to test a mechanism to reduce the knee adduction moment by testing the hypothesis that increased medio-lateral trunk sway can reduce the knee adduction moment during ambulation in healthy subjects, and to examine the possibility that increasing medio-lateral trunk sway can produce similar potentially adverse secondary gait changes previously associated with reduced knee adduction

Annegret Mündermann; Jessica L. Asay; Lars Mündermann; Thomas P. Andriacchi

2008-01-01

10

Polychaete trunk neuroectoderm converges and extends by mediolateral cell intercalation  

PubMed Central

During frog and fish development, convergent extension movements transform the spherical gastrula into an elongated neurula. Such transformation of a ball- into a worm-shaped embryo is an ancestral and fundamental feature of bilaterian development, yet this is modified or absent in the protostome model organisms Caenorhabditis or Drosophila. In the polychaete annelid Platynereis dumerilii, early embryonic and larval stages resemble a sphere that subsequently elongates into worm shape. Cellular and molecular mechanisms of polychaete body elongation are yet unknown. Our in vivo time-lapse analysis of Platynereis axis elongation reveals that the polychaete neuroectoderm converges and extends by mediolateral cell intercalation. This occurs on both sides of the neural midline, the line of fusion of the slit-like blastopore. Convergent extension moves apart mouth and anus that are both derived from the blastopore. Tissue elongation is actin-dependent but microtubule-independent. Dependence on JNK activity and spatially restricted expression of strabismus indicates involvement of the noncanonical Wnt pathway. We detect a morphogenetic boundary between the converging and extending trunk neuroectoderm and the anterior otx-expressing head neuroectoderm that does not elongate. Our comparative analysis uncovers striking similarities but also differences between convergent extension in the polychaete and in the frog (the classical vertebrate model for convergent extension). Based on these findings, we propose that convergent extension movements of the trunk neuroectoderm represent an ancestral feature of bilaterian development that triggered the separation of mouth and anus along the elongating trunk. PMID:17301244

Steinmetz, Patrick R. H.; Zelada-Gonzáles, Fabiola; Burgtorf, Carola; Wittbrodt, Joachim; Arendt, Detlev

2007-01-01

11

The Angular Momentum Dichotomy  

NASA Astrophysics Data System (ADS)

In the context of the formation of spiral galaxies the evolution and distribution of the angular momentum of dark matter halos have been discussed for more than 20 years, especially the idea that the specific angular momentum of the halo can be estimated from the specific angular momentum of its disk (e.g. Fall & Efstathiou (1980), Fall (1983) and Mo et al. (1998)). We use a new set of hydrodynamic cosmological simulations called Magneticum Pathfinder which allow us to split the galaxies into spheroidal and disk galaxies via the circularity parameter ?, as commonly used (e.g. Scannapieco et al. (2008)). Here, we focus on the dimensionless spin parameter ? = J |E|1/2 / (G M5/2) (Peebles 1969, 1971), which is a measure of the rotation of the total halo and can be fitted by a lognormal distribution, e.g. Mo et al. (1998). The spin parameter allows one to compare the relative angular momentum of halos across different masses and different times. Fig. 1 reveals a dichotomy in the distribution of ? at all redshifts when the galaxies are split into spheroids (dashed) and disk galaxies (dash-dotted). The disk galaxies preferentially live in halos with slightly larger spin parameter compared to spheroidal galaxies. Thus, we see that the ? of the whole halo reflects the morphology of its central galaxy. For more details and a larger study of the angular momentum properties of disk and spheroidal galaxies, see Teklu et al. (in prep.).

Teklu, Adelheid; Remus, Rhea-Silvia; Dolag, Klaus; Burkert, Andreas

2015-02-01

12

In vitro analysis of muscle activity illustrates mediolateral decoupling of hind and mid foot bone motion.  

PubMed

Activity of the extrinsic ankle-foot muscles is typically described for the whole foot. This study determines if this muscle activity is also confirmed for individual foot segments defined in multi-segment foot models used for clinical gait analysis. Analysis of the individual bone motion can identify functional complexes within the foot and evaluates the influence of an altered foot position on muscle activity. A custom designed and built gait simulator incorporating pneumatic actuators is used to control the muscle force of six muscle groups in cadaveric feet. Measurements were performed in three static postures in which individual muscle force was incrementally changed. The motion of four bone embedded LED-clusters was measured using a Krypton motion capture system and resulting motion of calcaneus, talus, navicular and cuboid was calculated. Results indicate that primary muscle activity at bone level corresponds with that described for the whole foot. Secondary activity is not always coherent for bones within one segment: decoupling of the movement of medial and lateral foot bones is documented. Furthermore, secondary muscle activity can alter according to foot position. The observed medio-lateral decoupling of the foot bones dictates the need to extend some of the multi-segment foot models currently used in clinical gait analysis. PMID:23159677

Burg, Josefien; Peeters, Koen; Natsakis, Tassos; Dereymaeker, Greta; Vander Sloten, Jos; Jonkers, Ilse

2013-05-01

13

A Dichotomy Theorem for Learning Quantified Boolean Formulas  

E-print Network

A Dichotomy Theorem for Learning Quantified Boolean Formulas V'ictor Dalmau Departament LSI the following classes of quantified boolean formulas. Fix a finite set of basic boolean functions. Take of basic boolean functions, the resulting set of formulas is either polynomially learnable from equivalence

Dalmau, Victor

14

Some Dichotomy Theorems on Constantfree Quantified Boolean Formulas  

E-print Network

Some Dichotomy Theorems on Constant­free Quantified Boolean Formulas V'ictor Dalmau \\Lambda In this paper we study the satisfiability of constant­free quanti­ fied boolean formulas. We consider the following classes of quantified boolean formulas. Fix a finite set of basic boolean logical functions. Take

Dalmau, Victor

15

Light touch and medio-lateral postural stability during short distance gait.  

PubMed

While standing, light fingertip touch on an external stable object attenuates sway and improves balance in healthy adults as well as in individuals with poor postural control. The effect of light touch on balance during gait is, however, not well known. Therefore, the purpose of this work was to study the effects of light fingertip touch on balance during gait. We hypothesized that similar to its effect during stance light touch would increase postural stability. Forty healthy young adults were tested under four gait conditions: (1) eyes open (EO), (2) eyes closed (EC), (3) eyes closed while lightly touching a static object on the right side of the walking lane (ECLTS), (4) eyes closed while lightly touching a dynamic object, namely, a stick that was moved forwards by the subject with the right hand (ECLTD). The main outcome measure was medio-lateral step width variability, a well established indicator of gait balance in the medio-lateral plane. During the EC condition, light touch of an external static object (ECLTS) decreased medio-lateral variability (i.e., balance improved); however, this stabilizing effect was not observed with light touch on the stick. The availability of self positional and spatial cues when touching a static external reference, and their absence when touching a stick that is moved forwards by the subject as he walks, can explain the different effects of light touch in the ECLTS vs the ECLTD gait conditions. PMID:25450148

Kodesh, E; Falash, F; Sprecher, E; Dickstein, R

2015-01-01

16

Reflections on the extinction-explosion dichotomy.  

PubMed

A wide range of stochastic processes that model the growth and decline of populations exhibit a curious dichotomy: with certainty either the population goes extinct or its size tends to infinity. There is an elegant and classical theorem that explains why this dichotomy must hold under certain assumptions concerning the process. In this note, I explore how these assumptions might be relaxed further in order to obtain the same, or a similar conclusion, and obtain both positive and negative results. PMID:25772708

Steel, Mike

2015-05-01

17

Medio-lateral balance impairment differentiates between Parkinson's disease and atypical parkinsonism.  

PubMed

In early disease stages, it can be difficult to differentiate clinically between Parkinson's disease and the various forms of atypical parkinsonism, like multiple system atrophy or progressive supranuclear palsy. Balance impairment in the medio-lateral plane (i.e. sideways) is often seen in patients with a form of atypical parkinsonism, but not in patients with Parkinson's disease. This is reflected by the distance between the feet during gait, which is typically normal (or even narrow) in Parkinson's disease, but widened in atypical parkinsonism. Estimating this stance width depends on subjective judgement, and is difficult to quantify in clinical practice. Here, we emphasize that this medio-lateral balance impairment can also be revealed using two simple tests: (1) inability to perform tandem gait (taking one or more side steps being abnormal); and (2) self-report by patients who have lost the ability to ride a bicycle. Both tests have a good diagnostic yield in differentiating between Parkinson's disease and atypical parkinsonism, even early in the course of the disease. PMID:25125484

Nonnekes, Jorik; Aerts, Marjolein B; Abdo, W F; Bloem, Bastiaan R

2014-01-01

18

The Dichotomy of List Homomorphisms for Digraphs  

E-print Network

The Dichotomy Conjecture for constraint satisfaction problems has been verified for conservative problems (or, equivalently, for list homomorphism problems) by Andrei Bulatov. An earlier case of this dichotomy, for list homomorphisms to undirected graphs, came with an elegant structural distinction between the tractable and intractable cases. Such structural characterization is absent in Bulatov's classification, and Bulatov asked whether one can be found. We provide an answer in the case of digraphs; the technique will apply in a broader context. The key concept we introduce is that of a digraph asteroidal triple (DAT). The dichotomy then takes the following form. If a digraph H has a DAT, then the list homomorphism problem for H is NP-complete; and a DAT-free digraph H has a polynomial time solvable list homomorphism problem. DAT-free graphs can be recognized in polynomial time.

Hell, Pavol

2010-01-01

19

The End of a Chemical Dichotomy.  

ERIC Educational Resources Information Center

Organic v inorganic dichotomy in chemistry has begun to disappear while a new formal research discipline, bioinorganic chemistry, is emerging. The field has been developed with the realization that a third of all proteins and bioenzymes contain an inorganic element such as a metal critical to their chemical nature. (Author/RE)

MOSAIC, 1980

1980-01-01

20

Are the mediolateral joint forces in the lower limbs different between scoliotic and healthy subjects during gait?  

PubMed Central

Introduction The quantification of internal joint efforts could be essential in the development of rehabilitation tools for patients with musculo-skeletal pathologies, such as scoliosis. In this context, the aim of this study was to compare the hips joint mediolateral forces during gait, between healthy subjects and adolescents with left lumbar or thoracolumbar scoliosis (AIS), categorized by their Cobb angle (CA). Material and methods Twelve healthy subjects, 12 AIS with CA between 20° and 40° and 16 AIS in pre-operative condition (CA : > 40°) walked at 4 km/h on an instrumented treadmill. The experimental set-up include six infrared cameras allow the computation of the tridimensional (3D) angular displacement and strain gauges located under the motor-driven treadmill allow the computation of ground reaction forces (GRF). The hips joint mediolateral forces were calculated using a 3D inverse dynamic of human body. One-way ANOVA was performed for the maximum, the minimum and the range of medio-lateral forces at each joint of the lower limbs. When appropriate, a Tukey's post hoc was performed to determine the differences. Results The mediolateral forces were significantly lower at the right hip for AIS with CA between 20° and 40° compared to healthy subject. Conclusion The spinal deformation leads to a reduced medio-lateral force at the right hip, which could gradually change the scheme of postural adjustments for AIS during gait. Further research on the quantification of the joint lower limb efforts should include the knee and ankle joints to evaluate the impact of spinal deformation on the lower limb dynamic behaviour in AIS patients.

2015-01-01

21

Finding corresponding regions of interest in mediolateral oblique and craniocaudal mammographic views  

SciTech Connect

In this paper we present a method to link potentially suspicious mass regions detected by a Computer-Aided Detection (CAD) scheme in mediolateral oblique (MLO) and craniocaudal (CC) mammographic views of the breast. For all possible combinations of mass candidate regions, a number of features are determined. These features include the difference in the radial distance from the candidate regions to the nipple, the gray scale correlation between both regions, and the mass likelihood of the regions determined by the single view CAD scheme. Linear Discriminant Analysis (LDA) is used to discriminate between correct and incorrect links. The method was tested on a set of 412 cancer cases. In each case a malignant mass, architectural distortion, or asymmetry was annotated. In 92% of these cases the candidate mass detections by CAD included the cancer regions in both views. It was found that in 82% of the cases a correct link between the true positive regions in both views could be established by our method. Possible applications of the method may be found in multiple view analysis to improve CAD results, and for the presentation of CAD results to the radiologist on a mammography workstation.

Engeland, Saskia van; Timp, Sheila; Karssemeijer, Nico [Department of Radiology, Radboud University Medical Centre, Nijmegen (Netherlands)

2006-09-15

22

Mediolateral hoof balance in relation to the handedness of apprentice farriers.  

PubMed

Horses that had been trimmed and shod by apprentice farriers were sourced from the Royal School of Military Engineering, Melton Mowbray (37 horses) and from the Household Cavalry, Knightsbridge (54 horses). The lateral and medial hoof wall angles of both forelimbs were measured using a Ruidoso hoof gauge by the same operator. The difference between the lateral and medial hoof wall angles for each horse was calculated and the results were compared between right-handed and left-handed farriers using the Mann-Whitney U test (P<0.05). There was a significant difference in the mediolateral hoof balance obtained between right-handed and left-handed farriers for each forelimb (P<0.001). Right-handed farriers were shown to create an imbalance in 47 per cent of left forelimbs and 46 per cent of right forelimbs assessed, while left-handed farriers created an imbalance in 41 per cent of left forelimbs and 71 per cent of right forelimbs. The tendency was for right-handed farriers to over-trim the medial (inner) aspect of the left forelimb and the lateral (outer) aspect of the right forelimb; the reverse was demonstrated for left-handed farriers. Performing a risk ratio confirmed these findings. PMID:21257560

Ronchetti, A; Day, P; Weller, R

2011-01-15

23

Does medio-lateral motion occur in the normal knee? An in-vitro study in passive motion.  

PubMed

Medio-lateral translation during knee flexion continues to raise controversy. Small population sizes, small joint flexion ranges, less-reliable measurement techniques and disparate experimental conditions led to inconsistent reports in the past. To study this subject with more accurate and reliable measurements, we carried out femur and tibia tracking in 22 intact cadaver knees during passive joint motion using a state-of-the-art surgical navigation system. Trackers with active light-emitting diodes were fixed onto the femur and tibia, and an instrumented pointer was used to digitize a number of anatomical landmarks. International recommendations were adopted for anatomical-based reference frame definitions and joint kinematic analysis. For the first time, knee joint translations were reported in both the femoral and tibial reference frames, and over a flexion/extension arc as large as 140°. During flexion, in the femoral reference frame, the center of the tibial plateau moved 4.8 ± 2.8mm medially when averaged over the specimens. In the tibial frame, the knee center moved 13.3 ± 5.7 mm laterally. The relative femoral-to-tibial medio-lateral translation was, on average over the specimens, nearly 20% of the width of the tibial plateau, and can be as large as 35%. Medio-lateral translation occurs in the natural normal knee joint. PMID:21176906

Belvedere, C; Leardini, A; Giannini, S; Ensini, A; Bianchi, L; Catani, F

2011-03-15

24

Effect of Running Speed and Leg Prostheses on Mediolateral Foot Placement and Its Variability  

PubMed Central

This study examined the effects of speed and leg prostheses on mediolateral (ML) foot placement and its variability in sprinters with and without transtibial amputations. We hypothesized that ML foot placement variability would: 1. increase with running speed up to maximum speed and 2. be symmetrical between the legs of non-amputee sprinters but asymmetrically greater for the affected leg of sprinters with a unilateral transtibial amputation. We measured the midline of the body (kinematic data) and center of pressure (kinetic data) in the ML direction while 12 non-amputee sprinters and 7 Paralympic sprinters with transtibial amputations (6 unilateral, 1 bilateral) ran across a range of speeds up to maximum speed on a high-speed force measuring treadmill. We quantified ML foot placement relative to the body’s midline and its variability. We interpret our results with respect to a hypothesized relation between ML foot placement variability and lateral balance. We infer that greater ML foot placement variability indicates greater challenges with maintaining lateral balance. In non-amputee sprinters, ML foot placement variability for each leg increased substantially and symmetrically across speed. In sprinters with a unilateral amputation, ML foot placement variability for the affected and unaffected leg also increased substantially, but was asymmetric across speeds. In general, ML foot placement variability for sprinters with a unilateral amputation was within the range observed in non-amputee sprinters. For the sprinter with bilateral amputations, both affected legs exhibited the greatest increase in ML foot placement variability with speed. Overall, we find that maintaining lateral balance becomes increasingly challenging at faster speeds up to maximum speed but was equally challenging for sprinters with and without a unilateral transtibial amputation. Finally, when compared to all other sprinters in our subject pool, maintaining lateral balance appears to be the most challenging for the Paralympic sprinter with bilateral transtibial amputations. PMID:25590634

Arellano, Christopher J.; McDermott, William J.; Kram, Rodger; Grabowski, Alena M.

2015-01-01

25

An Apparatus to Quantify Anteroposterior and Mediolateral Shear Reduction in Shoe Insoles  

PubMed Central

Background Many of the physiological changes that lead to diabetic foot ulceration, such as muscle atrophy and skin hardening, are manifested at the foot–ground interface via pressure and shear points. Novel shear-reducing insoles have been developed, but their magnitude of shear stiffness has not yet been compared with regular insoles. The aim of this study was to develop an apparatus that would apply shear force and displacement to an insole’s forefoot region, reliably measure deformation, and calculate insole shear stiffness. Methods An apparatus consisting of suspended weights was designed to test the forefoot region of insoles. Three separate regions representing the hallux; the first and second metatarsals; and the third, fourth, and fifth metatarsals were sheared at 20 mm/min for displacements from 0.1 to 1.0 mm in both the anteroposterior and mediolateral directions for two types of insoles (regular and shear reducing). Results Shear reduction was found to be significant for the intervention insoles under all testing conditions. The ratio of a regular insole’s effective stiffness and the experimental insole’s effective stiffness across forefoot position versus shear direction, gait instance versus shear direction, and forefoot position versus gait instance was 270% ± 79%, 270% ± 96%, and 270% ± 86%, respectively. The apparatus was reliable with an average measured coefficient of variation of 0.034 and 0.069 for the regular and shear-reducing insole, respectively. Conclusions An apparatus consisting of suspended weights resting atop three locations of interest sheared across an insole was demonstrated to be capable of measuring the insole shear stiffness accurately, thus quantifying shear-reducing effects of a new type of insole. PMID:23567000

Belmont, Barry; Wang, Yancheng; Ammanath, Peethambaran; Wrobel, James S.; Shih, Albert

2013-01-01

26

The kraepelinian dichotomy viewed by neuroimaging.  

PubMed

The Kraepelinian dichotomy between schizophrenia (SZ) and bipolar disorder (BD) is being challenged by recent epidemiological and biological studies. We performed a comparative review of neuroimaging features in both conditions at several scales: whole-brain and regional volumes, brain activity, connectivity, and networks. Structural volumetric neuroimaging studies suggest a common pattern of volume decreases, but networks studies reveal a clearer distinction between BD and SZ with an altered connectivity generalized to all brain networks in SZ and restricted to limbic, paralimbic, and interhemispheric networks in BD. PMID:25533269

d'Albis, Marc-Antoine; Houenou, Josselin

2015-03-01

27

Dichotomies in Music Education--Real or Unreal?  

ERIC Educational Resources Information Center

In this keynote, the author discusses dichotomies having to do with: (1) technology/digital proponents versus non-technology/analogue proponents; (2) a formal/formalist position versus an informal/informalist position; and (3) educator/teacher views versus artist/musician views. The author often wonders what the essence of these dichotomies are,…

Espeland, Magne

2010-01-01

28

Age and Origin of the Crustal Dichotomy in Eastern Mars  

NASA Technical Reports Server (NTRS)

The crustal dichotomy in eastern Mars is largely due to the very large impact which produced the Utopia Basin. Buried impact basins on the Utopia Basin constrain the Utopia impact (and therefore the dichotomy) to be very Early Noachian in age. Additional information is contained in the original extended abstract.

Frey, H. V.

2002-01-01

29

Proceedings of Symposia in Pure Mathematics On the dichotomy in the heat kernel two sided estimates  

E-print Network

kernel gives rise to the heat semigroup {P t } t>0 where P t is the oper­ ator on functions defined by (1Proceedings of Symposia in Pure Mathematics On the dichotomy in the heat kernel two sided estimates. Definition 1.1. A family {p t } t>0 of measurable functions p t (x, y) on M �M is called a heat kernel

Grigor'yan, Alexander

30

The Biological Implausibility of the Nature-Nurture Dichotomy and What It Means for the Study of Infancy  

ERIC Educational Resources Information Center

Since the time of the Greeks, philosophers and scientists have wondered about the origins of structure and function. Plato proposed that the origins of structure and function lie in the organism's nature whereas Aristotle proposed that they lie in its nurture. This nature-nurture dichotomy and the emphasis on the origins question has had a…

Lewkowicz, David J.

2011-01-01

31

A dichotomy in radio jet orientations  

E-print Network

We examine the relative orientations of radio jets, central dust and stars in low-power (i.e., FR I and FR I/II) radio galaxies. We use the position angles of jet and dust to constrain the three-dimensional angle $\\theta_{\\rm DJ}$ between jet and dust. For galaxies with filamentary dust 'lanes' (which tend to be misaligned with the galaxy major axis) the jet is approximately perpendicular to the dust structure, while for galaxies with elliptical dust distributions (typically aligned with the galaxy major axis) there is a much wider distribution of $\\theta_{\\rm DJ}$. nThe dust ellipses are consistent with being nearly circular thin disks viewed at random viewing angles. The lanes are likely warped, unsettled dust structures. We consider two scenarios to explain the dust/jet orientation dichotomy.

Gijs Verdoes Kleijn; Tim de Zeeuw

2005-11-30

32

Proceedings of Symposia in Pure Mathematics On the dichotomy in the heat kernel two sided estimates  

E-print Network

:= L2 (M, µ), (1.3) M pt(x, y)f(y)dµ(y) L2 - f(x) as t 0 + . Any heat kernel gives rise to the heatProceedings of Symposia in Pure Mathematics On the dichotomy in the heat kernel two sided estimates. Definition 1.1. A family {pt}t>0 of measurable functions pt(x, y) on M � M is called a heat kernel

Grigor'yan, Alexander

33

CAN PLANETARY INSTABILITY EXPLAIN THE KEPLER DICHOTOMY?  

SciTech Connect

The planet candidates discovered by the Kepler mission provide a rich sample to constrain the architectures and relative inclinations of planetary systems within approximately 0.5 AU of their host stars. We use the triple-transit systems from the Kepler 16 months data as templates for physical triple-planet systems and perform synthetic transit observations, varying the internal inclination variation of the orbits. We find that all the Kepler triple-transit and double-transit systems can be produced from the triple-planet templates, given a low mutual inclination of around 5 Degree-Sign . Our analysis shows that the Kepler data contain a population of planets larger than four Earth radii in single-transit systems that cannot arise from the triple-planet templates. We explore the hypothesis that high-mass counterparts of the triple-transit systems underwent dynamical instability to produce a population of massive double-planet systems of moderately high mutual inclination. We perform N-body simulations of mass-boosted triple-planet systems and observe how the systems heat up and lose planets by planet-planet collisions, and less frequently by ejections or collisions with the star, yielding transits in agreement with the large planets in the Kepler single-transit systems. The resulting population of massive double-planet systems nevertheless cannot explain the additional excess of low-mass planets among the observed single-transit systems and the lack of gas-giant planets in double-transit and triple-transit systems. Planetary instability of systems of triple gas-giant planets can be behind part of the dichotomy between systems hosting one or more small planets and those hosting a single giant planet. The main part of the dichotomy, however, is more likely to have arisen already during planet formation when the formation, migration, or scattering of a massive planet, triggered above a threshold metallicity, suppressed the formation of other planets in sub-AU orbits.

Johansen, Anders; Davies, Melvyn B.; Church, Ross P.; Holmelin, Viktor [Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, SE-221 00 Lund (Sweden)

2012-10-10

34

Kinetic measures of restabilisation during volitional stepping reveal age-related alterations in the control of mediolateral dynamic stability.  

PubMed

Research examining age-related changes in dynamic stability during stepping has recognised the importance of the restabilisation phase, subsequent to foot-contact. While regulation of the net ground reaction force (GRFnet) line of action is believed to influence dynamic stability during steady-state locomotion, such control during restabilisation remains unknown. This work explored the origins of age-related decline in mediolateral dynamic stability by examining the line of action of GRFnet relative to the centre of mass (COM) during restabilisation following voluntary stepping. Healthy younger and older adults (n=20 per group) performed three single-step tasks (varying speed and step placement), altering the challenge to stability control. Age-related differences in magnitude and intertrial variability of the angle of divergence of GRFnet line of action relative to the COM were quantified, along with the peak mediolateral and vertical GRFnet components. The angle of divergence was further examined at discrete points during restabilisation, to uncover events of potential importance to stability control. Older adults exhibited a reduced angle of divergence throughout restabilisation. Temporal and spatial constraints on stepping increased the magnitude and intertrial variability of the angle of divergence, although not differentially among the older adults. Analysis of the time-varying angle of divergence revealed age-related reductions in magnitude, with increases in timing and intertrial timing variability during the later phase of restabilisation. This work further supports the idea that age-related challenges in lateral stability control emerge during restabilisation. Age-related alterations during the later phase of restabilisation may signify challenges with reactive control. PMID:25262875

Singer, Jonathan C; McIlroy, William E; Prentice, Stephen D

2014-11-01

35

Constraints on Early Mars Evolution and Dichotomy Origin from Relaxation Modeling of Dichotomy Boundary in the Ismenius Region  

NASA Technical Reports Server (NTRS)

The Martian dichotomy is a global feature separating the northern and southern hemispheres. The 3.5 - 4 Gyr old feature is manifested by a topographic difference of 2-6 km and crustal thickness difference of approx. 15 - 30 km between the two hemispheres. In the Ismenius region, sections of the boundary are characterized by a single scarp with a slope of approx. 20 deg. - 23 deg. and are believed to be among the most well preserved parts of the dichotomy boundary. The origin of the dichotomy is unknown. Endogenic hypotheses do not predict the steep slopes (scarps) of the dichotomy boundary. Exogenic models for forming the northern lowlands by impact cratering, associate the scarps along the dichotomy boundary with craters' rims, but are not globally consistent with the topography and gravity. In order to better understand the origin of the Martian dichotomy, it is necessary to know if the steep scarps along the boundary represent the original shape of the dichotomy. Smrekar et al. presented evidence showing that the boundary scarp in Ismenius is a fault along which the highland crust was down faulted. We test whether the relaxation process could produce faulting along the dichotomy boundary and examine the crustal and mantle conditions that would allow for faulting to occur within 1 Gyr and preserve the long wavelength topography over another 3 Gyr. We approach the problem by a combination of numerical and semi-analytical modeling. We test different viscosity profiles and crustal thicknesses by comparing our modeled magnitude, location and timing of plastic strain and displacements to detailed geologic observations in the Ismenius region.

Guest, A.; Smrekar, S. E.

2004-01-01

36

Dawn: Testing Paradigms by Exploring Dichotomies  

NASA Astrophysics Data System (ADS)

NASA’s Dawn mission represents a series of “firsts” for major NASA missions. Dawn is the first major NASA science mission to use ion propulsion engines, allowing Dawn to be the first mission to orbit one target and then leave its gravity well to explore a second destination. Dawn is the first science mission to the main asteroid belt, reaching protoplanet Vesta in summer 2011, and will be the first mission to reach a “dwarf planet” when it arrives at Ceres in 2015. By targeting both Vesta and Ceres, Dawn explores two intriguing dichotomies in the solar system, that of the dry rocky planets and the wet icy bodies (Fire and Ice) and the dichotomy between planets and asteroids. Is there a clear dividing line here? Vesta, the second most massive asteroid, is a protoplanet: a round, mostly intact asteroid that bears more resemblance to a planet than to smaller asteroids. Vesta is also the likely parent body of the HED meteorites that richly populate Earth’s meteorite collections. It is possible to hold a piece of Vesta in your hands. From the HED meteorites, scientists have learned the Vesta is one of few differentiated asteroids. And from its spectrum, rich in basaltic minerals, it is known to be much like a mini-version of Earth’s Moon and Mercury. Vesta’s surface once was home to floods of lava not unlike those found still today on the Earth. Vesta is very similar to a terrestrial planet. Ceres is the giant of the asteroid belt with a hydrostatic shape that earns it a dwarf planet classification. Like its larger cousins, Ceres’ round shape suggests that the body may be differentiated, but due to its low density, Ceres’ interior is more like an icy moon of Jupiter. Beneath a relatively thin clay veneer probably lies an ice-rich mantle and rocky core, and even possibly a liquid ocean. With such enticing questions posed for Vesta and Ceres, Dawn will enable scientists and the public alike to explore how planets were born, how fire and ice have shaped the solar system, and have a chance to push the boundaries of our own classification system. Dawn’s set of instrumentation, with cameras, a visible and infrared spectrometer, a gamma ray and neutron detector and radio science, will produce a wealth of information about two previously unexplored, diverse and yet somehow familiar worlds. Communication of the lessons learned by Dawn from the scientists to the public has and will occur over a range of interfaces, including a series of online activities such as Find a Meteorite, Clickworkers and a simulation of an ion engine. Other activities include Dawn “Science of the Day” archives, fun family activities and games as well as classroom materials and outreach events. Since the two bodies are the brightest sources in the main belt, an integral part of Dawn’s journey has been the integration of amateur and “backyard” astronomers. All these activities allow us to share the science with the public. Dawn arrives at Vesta in the middle of the Year of the Solar System in July 2011 and will depart for Ceres as the YSS ends.

Russell, C. T.; Schmidt, B. E.; Wise, J.; Ristvey, J.; Raymond, C. A.

2010-12-01

37

Development/Plasticity/Repair ALCAM Regulates Mediolateral Retinotopic Mapping in the  

E-print Network

, because the phenotypes of mice with Ephrin or Eph loss-of- function mutations are not fully penetrant and Maness, 2003; Buhusi et al., 2008). Coupling the L1 cytoplasmic domain to filamentous actin by reversible (Buhusi et al., 2008). Tyrosine to histidine mutation of a critical residue in the L1 cytoplasmic domain

Dokholyan, Nikolay V.

38

Geology of the Eastern Margin of Tempe Terra with Implications for Mars Dichotomy Modifications  

NASA Astrophysics Data System (ADS)

Here we report Fe/Mg phyllosilicate detections at the eastern margin of Tempe Terra, exposed as a result of dichotomy erosional processes. These studies will shed light on the geology of Tempe Terra and the modification processes near dichotomy.

Pan, L.; Ehlmann, B. L.

2014-07-01

39

MOLA Topography of the Crustal Dichotomy Boundary Zone, Mars  

NASA Technical Reports Server (NTRS)

Mars Orbiter Laser Altimeter (MOLA) profiles frequently cross the crustal dichotomy boundary where the transition zone (TZ) between cratered highland terrain (CT) and lowland smooth plains (SP) is marked by mesas and knobby terrain. The detailed topographic character of the boundary zone is longitudinally variable, as is the geomorphology of the TZ. Some portions of the boundary are associated with an outer ring of the Utopia impact basin; MOLA topography is consistent with this. The regional character of the boundary topography is a 2-4 km step function from nearly flat SP to almost as flat CT. This rise has a regional slope of 1-2 degrees, 50-100 times that of the Cr and SP away from TZ, which suggests a significant change in crustal properties (thickness, composition or both) across the TZ. The overall topography is very similar to that at some passive continent-oceanic crustal margins on the Earth, with the seafloor allowed to adjust upward after removal of the overlying water. A possible temporal constraint on the CT/SP elevation difference comes from two MOLA profiles which pass through two large (150 km diameter) craters located at the boundary in Aeolis. The N and S rims of the more degraded crater are at the same elevation; north of the N rim the topography drops by greater than 2 km to the floor of the TZ. This crater predates the elevation offset between CT and TZ floor. The better preserved crater (Gale) has a N rim 2 km lower than its S rim, and appears to have been emplaced on a pre-existing regional slope of about I degree. Gale probably post- dates the elevation difference between CT and TZ floor. Based on the stratigraphy of the units in which these craters are found, the elevation difference appears to have been in place in the Mid to Late Noachian.

Frey, Herbert V.; E. H., Susan; H., James

1998-01-01

40

The Dichotomy of Thermal Convection in Enceladus' , Gabriel Tobieb  

E-print Network

heat fluxes over the rest of the satellite. To understand the conditions that can give rise hemispheric dichotomy of tectonism and heat flux, with geologically young, heavily tectonized terrains and a high heat flux in the south polar terrains (SPT) and relatively ancient terrains with presumably lower

41

Medio-lateral stability of sit-to-walk performance in older individuals with and without fear of falling.  

PubMed

Most falls in older people are due to loss of balance during everyday locomotion, e.g., when initiating walking from sitting; sit-to-walk (STW). It has been considered that the broader stride width in walking that is seen in many people with fear of falling (FoF) does not increase stability, but could be predictive of future falls because of increased medio-lateral (ML) velocity of the body centre of mass (CoM). This study was aimed to examine step-, velocity- and stability-related parameters, focusing on ML stability, in STW performance of people with and without FoF. Ten subjects with FoF and 10 matched controls, aged > or = 70 years, were included. Kinematic and kinetic data were collected in a laboratory. Stability parameters were calculated from a formula implying that the vertical projection of the CoM extrapolated by adding its velocity times a factor radicall/g (height of inverted pendulum divided by gravity) should fall within the base of support (BoS). A related spatial margin of stability (SMoS), defined as the minimum distance from the extrapolated CoM (XCoM) to the boundaries of the BoS, was also calculated. In the phase 'seat-off-second-toe-off', the FoF group had significantly (p<0.05) shorter and broader steps, lower forward but similar ML CoM velocity, and broader CoM and XCoM widths. The FoF group therefore exhibited a disproportionately large sideways velocity compared to the controls. This indicates that STW may be a hazardous transfer for older people with FoF, which should be relevant in assessment and training aimed at preventing falls. PMID:20189390

Aberg, Anna Cristina; Frykberg, Gunilla Elmgren; Halvorsen, Kjartan

2010-04-01

42

Dichotomy in the definition of prescriptive information suggests both prescribed data and prescribed algorithms: biosemiotics applications in genomic systems  

PubMed Central

The fields of molecular biology and computer science have cooperated over recent years to create a synergy between the cybernetic and biosemiotic relationship found in cellular genomics to that of information and language found in computational systems. Biological information frequently manifests its "meaning" through instruction or actual production of formal bio-function. Such information is called Prescriptive Information (PI). PI programs organize and execute a prescribed set of choices. Closer examination of this term in cellular systems has led to a dichotomy in its definition suggesting both prescribed data and prescribed algorithms are constituents of PI. This paper looks at this dichotomy as expressed in both the genetic code and in the central dogma of protein synthesis. An example of a genetic algorithm is modeled after the ribosome, and an examination of the protein synthesis process is used to differentiate PI data from PI algorithms. PMID:22413926

2012-01-01

43

Tharsis: Consequence of Mars' Dichotomy and Layered Mantle  

NASA Astrophysics Data System (ADS)

The two largest and most striking features on Mars are the crustal dichotomy, the nearly hemispheric division in topography, gravity, crustal thickness, and age, and Tharsis, a volcanic center active from the Noachian to the present. Tharsis' long-term persistence of localized volcanism is, to the best of our knowledge, unique in the solar system. Explaining the timing of Tharsis volcanism, from initiation early in martian history to recent activity, has been an enduring challenge. Here we present an model of the martian mantle that can explain early and persistent volcanism at Tharsis by incorporating the effects of the crustal dichotomy and a compositionally layered mantle. As the crust is expected to be enriched in heat-producing elements, this dichotomy in thickness leads to a dichotomous heat flux boundary condition on the mantle, which affects the internal dynamics. The evidence for layering includes the ability of a layered mantle to simultaneously meet a chondritic bulk composition and the moment-of-inertia factor (Elkins-Tanton et al., in revision), which can not be done with a one-layered mantle. In addition, studies of the martian meteorites suggest that the martian mantle is heterogeneous, a constraint that can be met with layering. We perform analog laboratory experiments with corn syrup to simulate Mars' thermal evolution. We vary the presence of a partial insulating lid, to simulate the effect of the dichotomy, and layering in the convecting fluid. We show that in the case of a layered mantle and an insulating lid, a large swell, which acts to localize upwelling plumes under the lid, forms early and endures for the scaled equivalent of billions of years. Linda T. Elkins-Tanton, E. M. Parmentier, and P. C. Hess, "Magma ocean fractional crystallization and cumulate overturn in terrestrial planets: implications for Mars," in revision for Meteoritics and Planetary Science.

Wenzel, M. J.; Manga, M.; Jellinek, A. M.

2003-12-01

44

Impact of posterior tibial nail malpositioning on iatrogenic injuries by distal medio-lateral interlocking screws. A cadaveric study on plastinated specimens.  

PubMed

In intramedullary tibial nailing, multi-planar locking makes stabilization of proximal and distal metaphyseal fractures possible. A known complication in intramedullary nailing of the tibia is iatrogenic injury to neuro-vascular structures caused by the insertion of locking screws. As shown in previous studies, the distal positioning of the nail is important, as it determines the course of the locking bolts. The goal of the present study was to display the consequences of posterior nail malpositioning with respect to the safety of the distal medio-lateral locking screws and the available options. Human cadaveric legs were plastinated according to the sequential plastination technique after intramedullary nailing of the tibia and were then cut transversely. The tibial nails were placed centrally or posteriorly. Macroscopic analysis showed a distinct drawback of posterior nail positioning, with diminished options for the placement of the locking screws and thereby a risk of damaging the anterior and posterior neuro-vascular bundles by distal medio-lateral locking screws. PMID:23409576

Wegmann, Kilian; Burkhart, Klaus Josef; Buhl, Jörg; Gausepohl, Thomas; Koebke, Jürgen; Müller, Lars Peter

2012-12-01

45

Dichotomy of Solar Coronal Jets: Standard Jets and Blowout Jets  

NASA Technical Reports Server (NTRS)

By examining many X-ray jets in Hinode/XRT coronal X-ray movies of the polar coronal holes, we found that there is a dichotomy of polar X-ray jets. About two thirds fit the standard reconnection picture for coronal jets, and about one third are another type. We present observations indicating that the non-standard jets are counterparts of erupting-loop H alpha macrospicules, jets in which the jet-base magnetic arch undergoes a miniature version of the blowout eruptions that produce major CMEs. From the coronal X-ray movies we present in detail two typical standard X-ray jets and two typical blowout X-ray jets that were also caught in He II 304 Angstrom snapshots from STEREO/EUVI. The distinguishing features of blowout X-ray jets are (1) X-ray brightening inside the base arch in addition to the outside bright point that standard jets have, (2) blowout eruption of the base arch's core field, often carrying a filament of cool (T 10(exp 4) - 10(exp 5) K) plasma, and (3) an extra jet-spire strand rooted close to the bright point. We present cartoons showing how reconnection during blowout eruption of the base arch could produce the observed features of blowout X-ray jets. We infer that (1) the standard-jet/blowout-jet dichotomy of coronal jets results from the dichotomy of base arches that do not have and base arches that do have enough shear and twist to erupt open, and (2) there is a large class of spicules that are standard jets and a comparably large class of spicules that are blowout jets.

Moore, R. L.; Cirtain, J. W.; Sterling, A. C.; Falconer, D. A.

2010-01-01

46

DICHOTOMY OF SOLAR CORONAL JETS: STANDARD JETS AND BLOWOUT JETS  

SciTech Connect

By examining many X-ray jets in Hinode/X-Ray Telescope coronal X-ray movies of the polar coronal holes, we found that there is a dichotomy of polar X-ray jets. About two thirds fit the standard reconnection picture for coronal jets, and about one third are another type. We present observations indicating that the non-standard jets are counterparts of erupting-loop H{alpha} macrospicules, jets in which the jet-base magnetic arch undergoes a miniature version of the blowout eruptions that produce major coronal mass ejections. From the coronal X-ray movies we present in detail two typical standard X-ray jets and two typical blowout X-ray jets that were also caught in He II 304 A snapshots from STEREO/EUVI. The distinguishing features of blowout X-ray jets are (1) X-ray brightening inside the base arch in addition to the outside bright point that standard jets have, (2) blowout eruption of the base arch's core field, often carrying a filament of cool (T {approx} 10{sup 4} - 10{sup 5} K) plasma, and (3) an extra jet-spire strand rooted close to the bright point. We present cartoons showing how reconnection during blowout eruption of the base arch could produce the observed features of blowout X-ray jets. We infer that (1) the standard-jet/blowout-jet dichotomy of coronal jets results from the dichotomy of base arches that do not have and base arches that do have enough shear and twist to erupt open, and (2) there is a large class of spicules that are standard jets and a comparably large class of spicules that are blowout jets.

Moore, Ronald L.; Cirtain, Jonathan W.; Sterling, Alphonse C.; Falconer, David A., E-mail: ron.moore@nasa.go [Space Science Office, VP62, Marshall Space Flight Center, Huntsville, AL 35812 (United States)

2010-09-01

47

A stellar population synthesis approach to the Oosterhoff dichotomy  

NASA Astrophysics Data System (ADS)

We use colour-magnitude diagram synthesis together with theoretical relations from non-linear pulsation models to approach the long-standing problem of the Oosterhoff dichotomy related to the distribution of the mean periods of fundamental RR Lyrae variables in globular clusters. By adopting the chemical composition determined from spectroscopic observations and a criterion to account for the hysteresis mechanism, we tuned age and mass loss to simultaneously reproduce the morphology of both the turn-off and the horizontal branch of a sample of 17 globular clusters of the Milky Way and of nearby dwarf galaxies in the crucial metallicity range (-1.9 < [Fe/H] < -1.4) where the Oostheroff transition is apparent. We find that the Oosterhoff dichotomy among Galactic globular clusters is naturally reproduced by models. The analysis of the relative impact of the various involved parameters indicates that the main responsibles of the dichotomy are the peculiar distribution of clusters in the age-metallicity plane and the hysteresis. In particular, there is a clear connection between the two main branches of the age-metallicity relation for Galactic globular clusters and the Oosterhoff groups. The properties of clusters' RR Lyrae belonging to other Oostheroff groups (OoInt and OoIII) are instead not well reproduced. While for OoIII clusters a larger helium abundance for a fraction of the cluster's stars can reconcile the model prediction with observations, some other parameter affecting both the horizontal branch morphology and the RR Lyrae periods is required to reproduce the behaviour of OoInt clusters.

Sollima, A.; Cassisi, S.; Fiorentino, G.; Gratton, R. G.

2014-10-01

48

The Henize sample of S stars; 1, The technetium dichotomy  

E-print Network

This paper is the first one in a series investigating the properties of the S stars belonging to the Henize sample (205 S stars with deltatechnetium. Only one `transition' case (Hen 140 = HD 120179, a star where only weak lines of technetium are detectable) is found in our sample. A resolution greater than R =30 000 is clearly required in order to derive unambiguous conclusions concerning the presence or absence of technetium. The Tc/no Tc dichotomy will be correlated with radial veloci...

Van Eck, S

1999-01-01

49

The Henize sample of S stars. I. The technetium dichotomy  

E-print Network

This paper is the first one in a series investigating the properties of the S stars belonging to the Henize sample (205 S stars with deltatechnetium. Only one `transition' case (Hen 140 = HD 120179, a star where only weak lines of technetium are detectable) is found in our sample. A resolution greater than R =30 000 is clearly required in order to derive unambiguous conclusions concerning the presence or absence of technetium. The Tc/no Tc dichotomy will be correlated with radial velocity and photometric data in a forthcoming paper.

S. Van Eck; A. Jorissen

1999-03-16

50

MOLA Topographic Variations Along the Crustal Dichotomy Boundary Zone in Eastern and Western Mars  

NASA Technical Reports Server (NTRS)

The topographic character of the martian crustal dichotomy boundary zone changes along the boundary, as does the morphological character of the boundary itself. Overall the elevation change from lowland plains to cratered uplands has the character of a step function, but the magnitude of the step and the slope of the ramp in the transition zone between the two relatively flat surfaces is different in different areas. Especially prominent is the difference between the boundaries in Deuteronilus-Ismenius Lacus and in Tempe Terra: Total relief in the transition zone in central Tempe is significantly greater than that in most of the eastern boundary zone. The correlation of topography with changing morphological character and mapped geologic units suggests that different parts of the boundary had different modification histories, and, perhaps, different origins as well.

Frey, H; Sakimoto, S.; Roark, J.

1999-01-01

51

Hydrophobic–hydrophilic dichotomy of the butterfly proboscis  

PubMed Central

Mouthparts of fluid-feeding insects have unique material properties with no human-engineered analogue: the feeding devices acquire sticky and viscous liquids while remaining clean. We discovered that the external surface of the butterfly proboscis has a sharp boundary separating a hydrophilic drinking region and a hydrophobic non-drinking region. The structural arrangement of the proboscis provides the basis for the wetting dichotomy. Theoretical and experimental analyses show that fluid uptake is associated with enlargement of hydrophilic cuticular structures, the legulae, which link the two halves of the proboscis together. We also show that an elliptical proboscis produces a higher external meniscus than does a cylindrical proboscis of the same circumference. Fluid uptake is additionally facilitated in sap-feeding butterflies that have a proboscis with enlarged chemosensory structures forming a brush near the tip. This structural modification of the proboscis enables sap feeders to exploit films of liquid more efficiently. Structural changes along the proboscis, including increased legular width and presence of a brush-like tip, occur in a wide range of species, suggesting that a wetting dichotomy is widespread in the Lepidoptera. PMID:23760299

Lehnert, Matthew S.; Monaenkova, Daria; Andrukh, Taras; Beard, Charles E.; Adler, Peter H.; Kornev, Konstantin G.

2013-01-01

52

Hydrophobic-hydrophilic dichotomy of the butterfly proboscis.  

PubMed

Mouthparts of fluid-feeding insects have unique material properties with no human-engineered analogue: the feeding devices acquire sticky and viscous liquids while remaining clean. We discovered that the external surface of the butterfly proboscis has a sharp boundary separating a hydrophilic drinking region and a hydrophobic non-drinking region. The structural arrangement of the proboscis provides the basis for the wetting dichotomy. Theoretical and experimental analyses show that fluid uptake is associated with enlargement of hydrophilic cuticular structures, the legulae, which link the two halves of the proboscis together. We also show that an elliptical proboscis produces a higher external meniscus than does a cylindrical proboscis of the same circumference. Fluid uptake is additionally facilitated in sap-feeding butterflies that have a proboscis with enlarged chemosensory structures forming a brush near the tip. This structural modification of the proboscis enables sap feeders to exploit films of liquid more efficiently. Structural changes along the proboscis, including increased legular width and presence of a brush-like tip, occur in a wide range of species, suggesting that a wetting dichotomy is widespread in the Lepidoptera. PMID:23760299

Lehnert, Matthew S; Monaenkova, Daria; Andrukh, Taras; Beard, Charles E; Adler, Peter H; Kornev, Konstantin G

2013-08-01

53

Beyond the intrinsic-extrinsic dichotomy: Self-determination in motivation and learning  

Microsoft Academic Search

Researchers have typically portrayed intrinsic and extrinsic motivation as dichotomous. Although this dichotomy has explanatory utility, we present a differentiated view of extrinsic motivation, arguing that the relative autonomy of one's motivated actions is more useful for characterizing the motivational basis of learning than is the undifferentiated intrinsic-extrinsic dichotomy. Our concept of autonomous extrinsic motivation is based on a developmental

C. Scott Rigby; Edward L. Deci; Brian C. Patrick; Richard M. Ryan

1992-01-01

54

Baire class one colorings and a dichotomy for countable unions of F rectangles  

E-print Network

Baire class one colorings and a dichotomy for countable unions of F rectangles Dominique LECOMTE. Such a partition gives a covering of the diagonal into countably many F squares. This leads to the study of countable unions of F rectangles. We give a Hurewicz-like dichotomy for such countable unions. 2010

Paris-Sud XI, Université de

55

Models of Sensory Deprivation: The Nature\\/Nurture Dichotomy and Spatial Representation in the Blind  

Microsoft Academic Search

It is argued that models of sensory deprivation often depend on a nativist versus empiricist dichotomy which has little basis in empirical fact. Fallacies about the nature of abilities and learning and about the interaction between sense modalities which follow from the dichotomy are examined in relation to explanations of spatial development in the blind. It is suggested that interactions

Susanna Millar

1988-01-01

56

Altered biomechanical strategies and medio-lateral control of the knee represent incomplete recovery of individuals with injury during single leg hop?  

PubMed Central

Anterior cruciate ligament (ACL) injury can result in failure to return to pre-injury activity levels and future osteoarthritis predisposition. Single leg hop is used in late rehabilitation to evaluate recovery and inform treatment but biomechanical understanding of this activity is insufficient. This study investigated single leg hop for distance aiming to evaluate if ACL patients had recovered: (1) landing strategies and (2) medio-lateral knee control. We hypothesized that patients with reconstructive surgery (ACLR) would have more similar landing strategies and knee control to healthy controls than patients treated conservatively (ACLD). 16 ACLD and 23 ACLR subjects were compared to 20 healthy controls (CONT). Kinematic and ground reaction force data were collected while subjects hopped their maximum distance. The main output parameters were hop distance, peak knee flexor angles and extensor moments and Fluency (a measure introduced to represent medio-lateral knee control). Statistical differences between ACL and control groups were analyzed using a general linear model univariate analysis, with COM velocity prior to landing as covariate. Hop distance was the smallest for ACLD and largest for CONT (p<0.001; ACLD 57.1±14.1; ACLR 75.1±17.8; CONT 77.7±14.07% height). ACLR used a similar kinematic strategy to CONT, but had a reduced peak knee extensor moment (p<0.001; ACLD 0.32±0.14; ACLR 0.31±0.16; CONT 0.42±0.13 BW.height). Fluency was reduced in both ACLD and ACLR (p=0.006; ACLD 0.13±0.34; ACLR 0.14±0.34; CONT 0.17±0.41 s). Clinical practice uses hopping distance to evaluate ACL patients' recovery. This study demonstrated that aspects such as movement strategies and knee control need to be evaluated. PMID:24342500

Roos, Paulien E.; Button, Kate; Sparkes, Valerie; van Deursen, Robert W.M.

2014-01-01

57

Cassini VIMS Preliminary Exploration of Titan's Surface Hemispheric Albedo Dichotomy  

NASA Technical Reports Server (NTRS)

We present preliminary evidence that suggests a hemispheric albedo dichotomy on Titan, the largest planetary satellite in the Solar System. We have also studied the photometric properties of several dark circular features on Titan's surface to test if they might be of impact origin. The evidence is derived from photometric analysis of selected surface regions taken at different Titanian longitudes and solar phase angles using images from the Cassini Saturn Orbiter Visual and Infrared Mapping Spectrometer (VIMS). The VIMS instrument is able to image Titan's surface at spectral windows (e.g. 2.02 microns) in its atmosphere where methane, the principal atmospheric absorber is transparent. Additional information is included in the original extended abstract.

Nelson, R. M.; Brown, R. H.; Hapke, B. W.; Smythe, W. D.; Kamp, L.; Boryta, M.; Baines, K. H.; Bellucci, G.; Bibring, J.-P.; Buratti, B. J.

2005-01-01

58

Dichotomy in the Dynamical Status of Massive Cores in Orion  

E-print Network

To study the evolution of high mass cores, we have searched for evidence of collapse motions in a large sample of starless cores in the Orion molecular cloud. We used the Caltech Submillimeter Observatory telescope to obtain spectra of the optically thin (\\H13CO+) and optically thick (\\HCO+) high density tracer molecules in 27 cores with masses $>$ 1 \\Ms. The red- and blue-asymmetries seen in the line profiles of the optically thick line with respect to the optically thin line indicate that 2/3 of these cores are not static. We detect evidence for infall (inward motions) in 9 cores and outward motions for 10 cores, suggesting a dichotomy in the kinematic state of the non-static cores in this sample. Our results provide an important observational constraint on the fraction of collapsing (inward motions) versus non-collapsing (re-expanding) cores for comparison with model simulations.

T. velusamy; R. Peng; D. Li; P. F. Goldsmith; William D. Langer

2008-10-14

59

Overcoming the dichotomy of quantity and quality in antibody responses.  

PubMed

Germinal centers (GCs) are specialized environments in which B cells mutate their BCR to identify new Abs with high affinity to a challenging Ag. B cells are selected in an evolutionary process of multiple rounds of mutation and selection. In the past decade, mechanisms of B cell migration, division, mutation, selection, and final differentiation have been extensively studied. Thereby, modulations of these mechanisms either optimize the quality, in terms of affinity, or the quantity of generated Abs, but never both, leading to an unclear effect on the overall efficiency of the Ab response. In this article, we predict with mathematical models that an affinity-dependent number of GC B cell divisions overcomes the dichotomy of quality and quantity, and has to be considered as a good target for immune interventions, in particular, in the elderly population with poor GC responses. PMID:25355924

Meyer-Hermann, Michael

2014-12-01

60

Quantifying the urban environment: a scale measure of urbanicity outperforms the urban-rural dichotomy  

PubMed Central

The rapid urbanization of the developing world has important consequences for human health. Although several authorities have called for better research on the relationships between urbanicity and health, most researchers still use a poor measurement of urbanicity, the urban-rural dichotomy. Our goal was to construct a scale of urbanicity using community level data from the Cebu Longitudinal Health and Nutrition Survey. We used established scale development methods to validate the new measure and tested its performance against the dichotomy. The new scale illustrated misclassification by the urban-rural dichotomy, and was able to detect differences in urbanicity, both between communities and across time, that were not apparent before. Furthermore, using a continuous measure of urbanicity allowed for better illustrations of the relationships between urbanicity and health. The new scale is a better measure of urbanicity than the traditionally used urban-rural dichotomy. PMID:17196724

Adair, Linda S

2007-01-01

61

Workshop on Hemispheres Apart: The Origin and Modification of the Martian Crustal Dichotomy  

NASA Technical Reports Server (NTRS)

This volume contains abstracts that have been accepted for presentation at the Workshop on Hemispheres Apart: The Origin and Modification of the Martian Crustal Dichotomy, September 30-October 1, 2004, Houston, Texas.

2004-01-01

62

The Relationship Between Fracture Sets and the South-Polar Terrain Dichotomy on Enceladus  

Microsoft Academic Search

Young fractured ice in the south-polar terrain (SPT) of Enceladus is separated from older regions of the moon by a narrow (9-50 km) band of deformation that defines a morphological dichotomy. The dichotomy is 100s of meters higher than the SPT and is divided into segments, some of which appear to be parallel fold-like structures and others that are dominated

D. A. Patthoff; S. A. Kattenhorn

2010-01-01

63

Complementarity of Politics and Administration as a Legitimate Alternative to the Dichotomy Model  

Microsoft Academic Search

Although the politics-administration dichotomy model has frequently been presented as historically important but conceptually and empirically faulty, the criticisms have missed two fundamental points. First, it is not—as commonly presumed—the founding theory of public administration in the United States but rather a poorly grounded characterization of the early literature that took hold in the late 1950s. The term dichotomy was

James H. Svara

1999-01-01

64

The Elliptical-Spheroidal and Elliptical-Elliptical Galaxy Dichotomies  

E-print Network

This paper summarizes Kormendy et al. (2009, ApJS, in press, arXiv:0810.1681). We confirm that spheroidal galaxies have fundamental plane correlations that are almost perpendicular to those for bulges and ellipticals. Spheroidals are not dwarf ellipticals. They are structurally similar to late-type galaxies. We suggest that they are defunct ("red and dead") late-type galaxies transformed by a variety of gas removal processes. Minus spheroidals, ellipticals come in two varieties: giant, non-rotating, boxy galaxies with cuspy cores and smaller, rotating, disky galaxies that lack cores. We find a new feature of this "E-E dichotomy": Coreless ellipticals have extra light at the center with respect to an inward extrapolation of the outer Sersic profile. We suggest that extra light is made in starbursts that swamp core scouring in wet mergers. In general, only giant, core ellipticals contain X-ray gas halos. We suggest that they formed in mergers that were kept dry by X-ray gas heated by active galactic nuclei.

John Kormendy

2008-12-03

65

Beyond the dichotomy: linking HIV prevention with care.  

PubMed

In the past decade, the global strategy against AIDS has focused primarily upon prevention. Regardless of the effectiveness of prevention efforts being made today and advances in treatments, the numbers of persons infected globally continues to grow at an alarming rate, especially in developing countries. With numbers of infections increasing, and the trend to more people learning their HIV status earlier, demands for care will mount dramatically into the next century. This paper examines the virtually unexplored role care can play in prevention and its potential to have a mitigating effect on the pandemic. Critical issues addressed include (i) the relationship between care, HIV and productivity; (ii) the role of both care and prevention in promoting acceptance of HIV/AIDS as a community problem; (iii) the role of care in decreasing the vulnerability to HIV in specific populations such as women and children; (iv) the role of care in sustaining behavior change over time for infected persons; and (v) the synergy between improved treatments and prevention. Future areas of research are proposed examining these prevention and care issues that move beyond the traditional dichotomy. PMID:9792358

MacNeil, J M; Anderson, S

1998-01-01

66

Magnetometer Data Tests Models for the Origin of the Martian Crustal Dichotomy; Dichotomy Models Constrain Timing of Martian Magnetic Field  

NASA Technical Reports Server (NTRS)

Measurements recently supplied by the MGS Magnetometer/Electron Reflectometer (MAG/ER) on MGS can be applied to test theories of the origin of the martian crustal dichotomy. Strong (+/- 1500 nT) magnetic anomalies are observed in the Martian crust. The observations can be summarized as follows: 1) strong crustal magnetic sources are generally confined to the southern highlands, although weaker (approx. 40 nT) anomalies were observed during close periapsis; 2) strong magnetic anomalies are absent in the vicinity of Hellas and Argyre; 3) the anomalies in the region 0 deg to 90 deg S, 120 deg to 240 deg west have a linear geometry, strike generally east west for 1000s km, and show several reversals. This latter point has led to the suggestion that some form of lateral plate tectonics may have been operative in the southern highlands of Mars. These observations have led previous workers to hypothesize that the magnetic anomalies were present prior to and were destroyed by the formation of Hellas and Argyre. As such large impacts are confined to the era of heavy bombardment, this places the time of formation of large magnetic anomalies prior to approx. 3.9 Ga. One obvious extension of this is that the northern lowlands lack significant anomalies because they were erased by impacts and/or the northern lowlands represent crust completely reheated above the Curie temperature. Preliminary observations of the distributions of the large crustal magnetic anomalies show that many of them extend continuously over the highland lowland boundary. This occurs particularly north of the boundary between 30 deg W and 270 deg W, corresponding to northern Arabia, but also occurs in southern Elysium (approx. 10 deg S, 200 deg) and the SW portion of Tharsis (approx. 15 deg S, 140 deg). This suggests that, in these areas, Noachian crust containing the greater than 3.9 Ga magnetic signature, lies beneath the northern highlands. This geometry can be used to test models for the formation of the martian crustal dichotomy. Additional information is contained in the original extended abstract.

Gilmore, M. S.

1999-01-01

67

Double-bundle medial patellofemoral ligament reconstruction with hamstring tendon autograft and mediolateral patellar tunnel fixation: a meta-analysis of outcomes and complications.  

PubMed

Medial patellofemoral ligament (MPFL) reconstruction is used to treat patellar instability and recurrent patellar dislocation. Anatomical studies have found the MPFL to be a double-bundle structure. We carried out a meta-analysis of studies reporting outcomes of patellofemoral reconstruction using hamstring tendon autograft in a double-bundle configuration and patellar fixation via mediolateral patellar tunnels. A literature search was undertaken with no language restriction in various databases from their year of inception to July 2012. The primary outcome examined was the post-operative Kujala score. We identified 320 MPFL reconstructions in nine relevant articles. The combined mean post-operative Kujala score was 92.02 (standard error (se) 1.4, p = 0.001) using a fixed effects model and 89.45 (se 37.9, p = 0.02) using random effect modelling. The reported rate of complications with MPFL reconstruction was 12.5% (40 of 320) with stiffness of the knee being the most common. High-quality evidence in assessing double-bundle MPFL reconstruction is lacking. The current literature consists of a mixture of prospective and retrospective case series. High-quality randomised trials evaluating this procedure are still awaited. PMID:23814240

Singhal, R; Rogers, S; Charalambous, C P

2013-07-01

68

Relaxation of the Martian Crustal Dichotomy Boundary in the Ismenius Region  

NASA Technical Reports Server (NTRS)

The origin of the Martian crustal dichotomy remains a puzzle that when solved can provide an insight to the geological and geophysical evolution of Mars. In this study we model crustal relaxation in order to better constrain the original topographic shape, rheology, and temperature of the Martian crust. Our approach is to model the detailed geologic history of the Ismenius region of Mars, including slope, strain, and timing of faulting [1]. This region may contain the best preserved section of the dichotomy boundary as it is relatively unaffected by large impacts and erosion. So far the only study Martian crustal relaxation [2] suggests that the original topographic shape of the dichotomy is preserved. However, in this area strain from faulting implies at least some relaxation [1].

Guest, A.; Smrekar, S. E.

2004-01-01

69

Geologic Evolution of the Martian Dichotomy and Plains Magnetization in the Ismenius Area of Mars  

NASA Technical Reports Server (NTRS)

The global dichotomy divides the northern lowlands from the southern highlands, except where interrupted by relatively young volcanic provinces and impact basins. An elevation change of 2-4 km is typical across the dichotomy, and more than 6 km locally, over distances of several 100s km to as much as 1300 km [1,2]. A variety of exogenic and endogenic formation models have been proposed. Distinguishing between these models would help constrain the overall thermal evolution of the planet, possibly timing of core formation, and the associated mantle heat flux over time. A first step is to determine whether or not gravitational relaxation plays a role in modifying the boundary. Nimmo and Stevenson [3] examined 10 profiles across the dichotomy and used models of gravitational relaxation to conclude the relaxation has not occurred. In this study we begin by considering the geologic history in detail as inputs for modeling [4].

Smrekar, S. E.; McGill, G. E.; Raymond, C. A.; Dimitriou, A. M.

2004-01-01

70

Iapetus: unique surface properties and a global color dichotomy from Cassini imaging.  

PubMed

Since 2004, Saturn's moon Iapetus has been observed repeatedly with the Imaging Science Subsystem of the Cassini spacecraft. The images show numerous impact craters down to the resolution limit of approximately 10 meters per pixel. Small, bright craters within the dark hemisphere indicate a dark blanket thickness on the order of meters or less. Dark, equator-facing and bright, poleward-facing crater walls suggest temperature-driven water-ice sublimation as the process responsible for local albedo patterns. Imaging data also reveal a global color dichotomy, wherein both dark and bright materials on the leading side have a substantially redder color than the respective trailing-side materials. This global pattern indicates an exogenic origin for the redder leading-side parts and suggests that the global color dichotomy initiated the thermal formation of the global albedo dichotomy. PMID:20007863

Denk, Tilmann; Neukum, Gerhard; Roatsch, Thomas; Porco, Carolyn C; Burns, Joseph A; Galuba, Götz G; Schmedemann, Nico; Helfenstein, Paul; Thomas, Peter C; Wagner, Roland J; West, Robert A

2010-01-22

71

Constraints on Thermal Evolution of Mars from Relaxation Models of Crustal and Topographic Dichotomy  

NASA Technical Reports Server (NTRS)

The early thermal evolution of Mars is largely unconstrained. Models such as degree one convection [1,2,3], plate tectonics [4], and a transition to stagnant lid [5] have been proposed to explain formation of the dichotomy, the Tharsis rise, crustal production, and dynamo evolution. Here we model both the early deformation of the dichotomy and the long-term preservation as a means of examining the plausibility of a range of early thermal evolution models. Constraints include the preservation of crustal thickness and topographic differences between the northern and southern hemispheres and the geologic history of the dichotomy [6]). Our previous modeling indicates that the lower crust must have been weak enough to allow for relaxation early on, but the Martian interior had to cool fast enough to preserve the crustal difference and the associated topographic difference (5 km) over approx. 3-3.5 Gyr [7].

Guest, A.; Smrekar, S. E.

2005-01-01

72

Constraints on the Evolution of the Dichotomy Boundary at 50-90E  

NASA Technical Reports Server (NTRS)

The global dichotomy is a fundamental feature of Mars. It marks the boundary between the highly cratered, older southern highlands, and the northern plains. Recent analysis of buried craters in the northern lowlands confirms the long held suspicion that they are comparable in age to the southern highlands, but with surficial deposits of younger material. A variety of exogenic and endogenic models have been proposed for the origin of the dichotomy, including multiple impacts, plate tectonics, and degree one convection produced by core formation, a plume under the lowlands, or a plume under the highlands. New gravity and topography data from the Mars Global Surveyor (MGS) Mission favor endogenic processes. In this study we examine MGS topography, gravity and magnetic field data to constrain the tectonic history the dichotomy in the region 30-60N and 50-90E, which encompasses portions of the Ismenius Lacus quadrangle. The dichotomy formed very early the history of Mars and has undergone extensive modification by impact cratering, erosion, and faulting. This history must be carefully interpreted in order to reconstruct the original nature of the dichotomy boundary and ultimately discriminate between models of origin. In the study area boundary-parallel faults are well preserved, and may be the result of gravitational relaxation. The geologic history has been examined in detail, including estimates of volumes of material eroded. Further, it is one of the few regions where there is a correlation between the free air gravity, magnetic anomalies, and the geology. This allows to constrain subsurface faulting beneath the lowlands fill material. In addition to being an excellent location to unravel the complex history of the dichotomy, this area preserves the transition from a highly magnetized highlands crust to an unmagnetized or slightly magnetized lowlands crust.

Smrekar, S. E.; Raymond, C. A.; Dimitriou, A.; McGill, G. E.

2003-01-01

73

Lakes, delta and volcanism at the Martian dichotomy. The case of Nepenthes Mensae.  

NASA Astrophysics Data System (ADS)

Martian dichotomy. The case of Nepenthes Mensae. M.A. de Pablo (1,2) and A. Pacifici (2) (1) Área de Geología. ESCET. Universidad Rey Juan Carlos. Móstoles, Madrid. Spain. (miguelangel.depablo@urjc.es), (2) International Research School of Planetary Sciences. Universitá d'Annunzio. Viale Pindaro, 42. Pescara, Italy. Martian dichotomy is marked by an important topographic step and a clear lineal orientation, especially at the western hemisphere. Nepenthes Mensae occur in one of these regions where these characteristics are clearly visible. Origin, tectonics and hydrological implications of the dichotomy were widely discussed by several authors. However, observation of HRSC, THEMIS Visible and MOC narrow angle images of Martian dichotomy on Nepenthes Mensae has revealed the existence of an interesting site (centred at 121.43E, 2.16N) where tectonic, volcanic, sedimentary and fluvial features are related and could be indicative of the complex geologic history of the Martian dichotomy, almost in this region. This site is characterized by an important topographic scarp between highlands and lowlands marked by a lineal orientation SE-NW. A small elongated volcanic edifice and some linear narrow reliefs, that we interpret as dikes highlighted by erosive processes, show same orientation. This volcano, 8 kilometers long, 4 kilometers wide and about 500 meters high, lies in a depression bordering the dichotomy. Partially covering the volcanic edifice there are sedimentary materials forming delta features. They represent the termination of one of channels coming from Martian highlands. The most recent delta seems to be a Gilbert-type (about 3.5 kilometers extended and 350 meters thick). However, our coarse estimations of volume of materials of this delta show that other previous important fluvial events should happen in order to erode its channel. The existence of two different overlapping delta funs in this place could be indicative of these previous episodes. Finally, although gullies are not visible on MOC narrow angle images of this area, some water courses are excavated at the Gilbert-type delta, and its possible sedimentary deposits are located near the elongated volcano, marking the most recent fluvial event at this area. Northward of this region, other depressions are characterized by possible shore- lnes. Different levels of water are marked by several strandlines. HRSC-derived DTM agrees with the shorelines hypothesis. Radiance maps created from THEMIS infrared night images show the higher temperature of materials outcropping on the floor of this basin and other depressions bordering the dichotomy. These maps allow us to interpret different origins for those materials, including cemented deposits and lavas. All this features shows the complex interactions among water, tectonics and volcanism in this area of the Martian dichotomy at Nepenthes Mensae.

de Pablo, M. A.; Pacifici, A.

74

Dichotomy Boundary Glaciation Models: Implications for Timing and Glacial Processes  

NASA Astrophysics Data System (ADS)

An integrated system with glacial features exists at 34E, 41N in the Deuteronilus-Protonilus Mensae region. This 30,000 km2 valley system is typical of dozens of fretted valleys in this region along the dichotomy boundary. We compare features described in current geological observations with results from the University of Maine Ice Sheet Model (UMISM) that we feel support the glacial interpretation of these features and also allow speculation as to the timing and processes responsible for the formation of these features. Geological observations identify evidence for a number of features that are felt to be indicative of glacial flow. These include: 1) localized alcoves from which emanate narrow, lobate concentric-ridged flows interpreted to be remnants of debris-covered glaciers; 2) alcove depressions perhaps indicating sublimation of material from relict ice-rich accumulation zones; 3) plateau-ridge remnants between alcoves typical of glacially eroded aretes; 4) horseshoe-shaped ridges upstream of topographic obstacles; 5) convergence and merging of LVF fabric in the down-valley direction; 6) deformation, distortion and folding of LVF in the vicinity of convergence; 7) LVF with pits and elongated troughs in distorted areas; 8) distinctive lobe-shaped termini with associated pitting where the LVF emerges into the northern lowlands. This evidence defines a coherent, unified flow regime extending from the upper valley reaches down to the northern lowlands. Additional support for the glacial hypothesis comes from a GCM for a dusty-atmosphere Mars with obliquity set to 35o and a water source in the Tharsis region. The GCM generates a pattern of ice accumulation in good agreement with these geological observations. This climate is what one might expect to follow a high- obliquity excursion of the sort that built ice sheets on the Tharsis volcanoes. UMISM as used here is an adaptation for the Martian environment of a thermo-mechanically coupled shallow- ice approximation terrestrial ice sheet model used for time-dependent reconstructions of Antarctic, Greenland, and paleo-icesheet evolution on Earth. Starting with no ice, the model is run for 2 million years. While this is longer that is expected for any steady climate to hold on Mars, it delivers a flow pattern that can be compared to the geological interpretations. We present ice thicknesses, surface elevations, and velocity maps at four times during the growth of this ice sheet. At 300Ka the flow from the sides has not yet merged in the centers of the valleys, a configuration that would not produce the turning flow observed. By 500Ka the beginning of a coherent downvalley flow is observed with ice from each side of the valley merging in the center. By 1000Ka there is a well-established valley glacier extending to the mouths of the valleys. Velocities are as high as 250 mm/year. By 1500Ka, the glacier extends out of the valleys onto the northern lowlands. Either 1000Ka or 1500Ka would produce the observed landforms. We also present comparisons of flow features in high-resolution THEMIS images with modeled flow at 1000Ka.

Fastook, J. L.; Head, J. W.

2008-12-01

75

Minority Parents as Researchers: Beyond a Dichotomy in Parent Involvement in Schooling  

ERIC Educational Resources Information Center

This article documents the work of parent-driven research teams in two school boards in the Greater Toronto Area. Motivated by a desire to move beyond a school-centred/family-centred dichotomy, this parent-lead project explores a middle space for collective learning among multiple stakeholders in publicly-funded schooling. Drawing on participatory…

Ippolito, John

2010-01-01

76

THE CSP DICHOTOMY HOLDS FOR DIGRAPHS WITH NO SOURCES AND NO SINKS  

E-print Network

conjectured in 1990 (using the language of graph homomorphisms) a CSP dichotomy for digraphs with no sources in the language of CSPs. The study of such problems, under this common framework, has applications in database/06/0664 and by the project of Ministry of Education under the grant No. MSM 0021620839. 1 #12;2 L.BARTO, M. KOZIK, AND T

Barto, Libor

77

Growth of the hemispheric dichotomy and the cessation of plate tectonics on Mars  

E-print Network

Growth of the hemispheric dichotomy and the cessation of plate tectonics on Mars A. Lenardic 2004. [1] Although Mars is currently not tectonically active, it may have experienced plate tectonics for the Earth predict that it should operate in the plate tectonic regime now but that it may have experienced

Nimmo, Francis

78

Baire class one colorings and a dichotomy for countable unions of $F_\\sigma$ rectangles  

E-print Network

We study the Baire class one countable colorings, i.e., the countable partitions into $F_\\sigma$ sets. Such a partition gives a covering of the diagonal into countably many $F_\\sigma$ squares. This leads to the study of countable unions of $F_\\sigma$ rectangles. We give a Hurewicz-like dichotomy for such countable unions.

Lecomte, Dominique

2010-01-01

79

Reconciling Evidenced-Based Research Practice with Rehabilitation Philosophy, Ethics and Practice: From Dichotomy to Dialectic  

ERIC Educational Resources Information Center

The recent shift in the helping professions to the implementation of evidenced-based practice (EBP) presents challenges to the field of rehabilitation counseling, most notably in the areas of integrating rehabilitation philosophy, ethics, and the relationship between research and practice. A dichotomy between the history and the future of the…

Tarvydas, Vilia; Addy, Amanda; Fleming, Allison

2010-01-01

80

Dichotomy, Dialectic and Dialogic: How Do Sociology Terms Assist Career Development Theory?  

ERIC Educational Resources Information Center

Three concepts from sociology--dichotomy and two extensions, dialectic and dialogic--are considered here as social-psychological tools for career practitioners who analyse and investigate career patterns, career motivations and career pathways, whether at career start or at further points of transition. These terms have macro-social applications…

Burns, Edgar A. M.

2012-01-01

81

Proving Dichotomy Theorems for Counting Problems University of Wisconsin, Madison  

E-print Network

, 2009 1 #12;In Celebration of Les Valiant 2 #12;3 #12;Hard to believe one man did all a bipartite graph G = (U, V, E). Each u U is a variable. Each v V is labeled by a constraint function. Find of Holant when all u U are labeled with the Equality function. Edge assignments can simulate vertex

Cai, Jin-Yi

82

The sense of smell, its signalling pathways, and the dichotomy of cilia and microvilli in olfactory sensory cells  

PubMed Central

Smell is often regarded as an ancillary perception in primates, who seem so dominated by their sense of vision. In this paper, we will portray some aspects of the significance of olfaction to human life and speculate on what evolutionary factors contribute to keeping it alive. We then outline the functional architecture of olfactory sensory neurons and their signal transduction pathways, which are the primary detectors that render olfactory perception possible. Throughout the phylogenetic tree, olfactory neurons, at their apical tip, are either decorated with cilia or with microvilli. The significance of this dichotomy is unknown. It is generally assumed that mammalian olfactory neurons are of the ciliary type only. The existance of so-called olfactory microvillar cells in mammals, however, is well documented, but their nature remains unclear and their function orphaned. This paper discusses the possibility, that in the main olfactory epithelium of mammals ciliated and microvillar sensory cells exist concurrently. We review evidence related to this hypothesis and ask, what function olfactory microvillar cells might have and what signalling mechanisms they use. PMID:17903277

2007-01-01

83

Geologic evolution of the Martian dichotomy in the Ismenius area of Mars and implications for plains magnetization  

Microsoft Academic Search

(1) The origin of the Martian dichotomy, which divides highlands from lowlands, is unknown. We examine a section of the dichotomy (50-90E) defined by steep scarps and normal faults. Stratigraphy and age relationships preclude the formation of the 2.5 km high boundary via erosion. The abrupt disappearance of topographic knobs 300-500 km to the northeast is interpreted as a buried

S. E. Smrekar; G. E. McGill; C. A. Raymond; A. M. Dimitriou

2004-01-01

84

Sedimentary resurfacing and fretted terrain development along the crustal dichotomy boundary, Aeolis Mensae, Mars  

NASA Astrophysics Data System (ADS)

The evolution of the Martian crustal dichotomy boundary, which separates the southern cratered highlands from the northern lowland plains by 1-3 km of elevation, remains among the fundamental outstanding issues in Mars research. For a study area at Aeolis Mensae we show that fretted terrain formed exclusively in a >2 km thick, late Noachian (~3.7 Ga) sedimentary deposit that overlies the base of an older, cratered dichotomy boundary slope. In this equatorial study area, fretted terrain does not exhibit the debris aprons or lineated valley fills that are attributed to ground ice in otherwise similar, midlatitude fretted terrain in Arabia Terra. The massive deposit of fine sand or loess was probably transported from the north by wind and trapped against the precursor dichotomy slope, producing a similar initial form to the younger Medusae Fossae layered materials that occur east of Aeolis Mensae. Contemporary with the latest Noachian to early Hesperian decline in fluvial erosion, the fretting process likely initiated as the massive layer's indurated surface was compromised by fracture, cratering, or collapse into possible voids. In these depressions, grain impact or contact with water disaggregated the fine sedimentary materials, which were then largely deflated by wind. The fretting process largely ended when liquid water was no longer widely available for weathering during the early Hesperian period, although some degradation of the region by aeolian and slope processes has continued to the present.

Irwin, Rossman P.; Watters, Thomas R.; Howard, Alan D.; Zimbelman, James R.

2004-09-01

85

Reciprocal Activation of Transcription Factors Underlies the Dichotomy between Proliferation and Invasion of Glioma Cells  

PubMed Central

Histology of malignant glioma depicts dense proliferative areas rich in angiogenesis as well as dissemination of neoplastic cells into adjacent brain tissue. Although the mechanisms that trigger transition from proliferative to invasive phenotypes are complex, the dichotomy of cell proliferation and migration, the “Go or Grow” hypothesis, argues for specific and coordinated regulation of these phenotypes. We investigated transcriptional elements that accompany the phenotypes of migration and proliferation, and consider the therapeutic significance of the “Go or Grow” hypothesis. Interrogation of matched core and rim regions from human glioblastoma biopsy specimens in situ (n?=?44) revealed higher proliferation (Ki67 labeling index) in cells residing at the core compared to the rim. Profiling activated transcription factors in a panel of migration-activated versus migration-restricted GBM cells portrayed strong NF-?B activity in the migratory cell population. In contrast, increased c-Myc activity was found in migration-restricted proliferative cells. Validation of transcriptional activity by NF-?B- or c-Myc-driven GFP or RFP, respectively, showed an increased NF-?B activity in the active migrating cells, whereas the proliferative, migration restricted cells displayed increased c-Myc activity. Immunohistochemistry on clinical specimens validated a robust phosphorylated c-Myc staining in tumor cells at the core, whereas increased phosphorylated NF-?B staining was detected in the invasive tumor cells at the rim. Functional genomics revealed that depletion of c-Myc expression by siRNA oligonucleotides reduced cell proliferation in vitro, but surprisingly, cell migration was enhanced significantly. Conversely, inhibition of NF-?B by pharmacological inhibitors, SN50 or BAY-11, decreased both cell migration in vitro and invasion ex vivo. Notably, inhibition of NF-?B was found to have no effect on the proliferation rate of glioma cells. These findings suggest that the reciprocal and coordinated suppression/activation of transcription factors, such as c-Myc and NF-?B may underlie the shift of glioma cells from a “growing-to-going” phenotype. PMID:23967279

Dhruv, Harshil D.; McDonough Winslow, Wendy S.; Armstrong, Brock; Tuncali, Serdar; Eschbacher, Jenny; Kislin, Kerri; Loftus, Joseph C.; Tran, Nhan L.; Berens, Michael E.

2013-01-01

86

Neither metaphysical dichotomy nor pure identity: clarifying the emergentist creed.  

PubMed

Emergentism is often misleadingly described as a monolithic "third way" between radical monism and pluralism. In the particular case of biology, for example, emergentism is perceived as a middle course between mechanicism and vitalism. In the present paper I propose to show that the conceptual landscape between monism and pluralism is more complex than this classical picture suggests. On the basis of two successive analyses-distinguishing three forms of tension between monism and pluralism and a distinction between derivational and functional reduction-I define three different versions of emergentism that can be considered as consistent middle courses between monism and pluralism (respectively theoretical, explanatory and causal emergence). I then emphasise the advantage of this taxonomy of the concepts of emergence by applying the results of my analysis to the historical controversy that pertains to the relationship between life and matter. PMID:23701955

Sartenaer, Olivier

2013-09-01

87

Does Black Hole Spin Play a Key Role in the Fsrq/bl Lac Dichotomy?  

NASA Astrophysics Data System (ADS)

It is believed that jets emerging from blazars (flat spectrum radio quasars (FSRQs) and BL Lacs) are almost aligned to the line-of-sight. BL Lacs usually exhibit lower luminosity and harder power law spectra at gamma-ray energies than FSRQs. It was argued previously that the difference in accretion rates is mainly responsible for the large observed luminosity mismatch between them. However, when intrinsic luminosities are derived by correcting for beaming effects, this mismatch is significantly reduced. We show that spin plays an important role to reveal the dichotomy of luminosity distributions between BL Lacs and FSRQs, suggesting BL Lacs to be low luminous and slow rotators compared to FSRQs.

Mukhopadhyay, Banibrata

2015-01-01

88

Regional Studies of Highland-Lowland Age Differences Across the Mars Crustal Dichotomy Boundary  

NASA Technical Reports Server (NTRS)

Regional differences in crater retention ages (CRAs) across the Mars dichotomy boundary are compared to the global highland-lowland age difference previously determined from visible and buried impact basins based on MOLA-derived Quasi-Circular Depressions (QCDs). Here Western Arabia (WA) is compared with Ismenius Lacus (IL). We find the buried lowlands in the two regions have total CRAs essentially identical to the global average. Even more intriguing, the WA cratered terrain appears to have a CRA like that of the adjacent buried lowlands,

Frey, H. V.; DeSoto, G. E.; Lazrus, R. M.

2005-01-01

89

Anterior/Posterior Competitive Deactivation/Activation Dichotomy in the Human Hippocampus as Revealed by a 3D Navigation Task  

PubMed Central

Anterior/posterior long axis specialization is thought to underlie the organization of the hippocampus. However it remains unclear whether antagonistic mechanisms differentially modulate processing of spatial information within the hippocampus. We used fMRI and a virtual reality 3D paradigm to study encoding and retrieval of spatial memory during active visuospatial navigation, requiring positional encoding and retrieval of object landmarks during the path. Both encoding and retrieval elicited BOLD activation of the posterior most portion of hippocampus, while concurrent deactivations (recently shown to reflect decreases in neural responses) were found in the most anterior regions. Encoding elicited stronger activity in the posterior right than the left hippocampus. The former structure also showed significantly stronger activity for allocentric vs. egocentric processing during retrieval. The anterior vs. posterior pattern mimics, from a functional point, although at much distinct temporal scales, the previous anatomical findings in London taxi drivers, whereby posterior enlargement was found at the cost of an anterior decrease, and the mirror symmetric findings observed in blind people, in whom the right anterior hippocampus was found to be larger, at the cost of a smaller posterior hippocampus, as compared with sighted people. In sum, we found a functional dichotomy whereby the anterior/posterior hippocampus shows antagonistic processing patterns for spatial encoding and retrieval of 3D spatial information. To our knowledge, this is the first study reporting such a dynamical pattern in a functional study, which suggests that differential modulation of neural responses within the human hippocampus reflects distinct roles in spatial memory processing. PMID:24475088

Duarte, Isabel Catarina; Ferreira, Carlos; Marques, João; Castelo-Branco, Miguel

2014-01-01

90

Lineated valley fill at the Martian dichotomy boundary: Nature and history of degradation  

NASA Astrophysics Data System (ADS)

The fretted terrain of the Martian dichotomy boundary is a key region for investigating landforms related to creep of ice and debris as it exhibits landforms comparable to morphologies of periglacial environments. Although features known as lobate debris aprons, lineated valley fills and concentric crater fills have been studied in great detail, basic questions concerned with the composition and the style of emplacement and degradation still remain unanswered. This study focuses on morphologies which are located in a near-circular depression located at the dichotomy escarpment in Deuteronilus Mensae. Analysis of high-resolution image data suggests an early formation of these features as the result of backward thermokarstic degradation of highland terrain. Geologically younger processes caused deposition and degradation of an ice-rich mantling deposit, which ultimately led to formation of creep morphologies that might have even been active in the geologically recent past. Intermixing of both degradational landform units form complex patterns that cannot be explained by a late stage (glacial) process alone. Morphological comparisons of lineated valley fill units with concentric crater fill landforms in Utopia Planitia strongly suggest comparable emplacement and degradation styles of these features. The sequential development consisting of an initial probably widespread thermokarstic degradation followed by later cyclic deposition of volatile material and continual thermokarstic degradation suggests that the development of parts of the Martian fretted terrain is directly related to climatic variations in the planet's history.

van Gasselt, S.; Hauber, E.; Neukum, G.

2010-08-01

91

Impact Constraints on the Age and Origin of the Crustal Dichotomy on Mars  

NASA Technical Reports Server (NTRS)

MOLA data have revealed a large population of "Quasi-Circular Depressions" (QCDs) with little or no visible expression in image data. These likely buried impact basins have important implications for the age of the lowland crust, how that compares with original highland crust, and when and how the crustal dichotomy may have formed. The buried lowlands are of Early Noachian age, likely slightly younger than the buried highlands but older than the exposed (visible) highland surface. A depopulation of large visible basins at diameters 800 to 1300 km suggests some global scale event early in martian history, maybe related to the formation of the lowlands andor the development of Tharsis. A suggested early disappearance of the global magnetic field can be placed within a temporal sequence of formation of the very largest impact basins. The global field appears to have disappeared at about the time the lowlands formed. It seems likely the topographic crustal dichotomy was produced very early in martian history by processes which operated very quickly. This and the preservation of large relic impact basins in the north- em hemisphere, which themselves can account for the lowland topography, suggest that large impacts played the major role in the origin Mars fundamental crustal feature.

Frey, H. V.

2004-01-01

92

Walking Smoothness Is Associated With Self-Reported Function After Accounting for Gait Speed  

PubMed Central

Background. Gait speed has shown to be an indicator of functional status in older adults; however, there may be aspects of physical function not represented by speed but by the quality of movement. The purpose of this study was to determine the relations between walking smoothness, an indicator of the quality of movement based on trunk accelerations, and physical function. Methods. Thirty older adults (mean age, 77.7±5.1 years) participated. Usual gait speed was measured using an instrumented walkway. Walking smoothness was quantified by harmonic ratios derived from anteroposterior, vertical, and mediolateral trunk accelerations recorded during overground walking. Self-reported physical function was recorded using the function subscales of the Late-Life Function and Disability Instrument. Results. Anteroposterior smoothness was positively associated with all function components of the Late-Life Function and Disability Instrument, whereas mediolateral smoothness exhibited negative associations. Adjusting for gait speed, anteroposterior smoothness remained associated with the overall and lower extremity function subscales, whereas mediolateral smoothness remained associated with only the advanced lower extremity subscale. Conclusion. These findings indicate that walking smoothness, particularly the smoothness of forward progression, represents aspects of the motor control of walking important for physical function not represented by gait speed alone. PMID:23689828

2013-01-01

93

The state–federal dichotomy in the effects of minimum wages on teenage employment in the United States  

Microsoft Academic Search

For the period 1984–1997, we find that state-level minimum wage hikes had no negative employment impact whereas federal hikes did. This dichotomy may account for the differences between the results of the ‘new economics of the minimum wage’ and time series studies.

Stephen Bazen; Julie Le Gallo

2009-01-01

94

Indigenous Knowledge and Education from the Quechua Community to School: Beyond the Formal/Non-Formal Dichotomy  

ERIC Educational Resources Information Center

In this article, we propose to approach Indigenous education beyond the formal/non-formal dichotomy. We argue that there is a critical need to conscientiously include Indigenous knowledge in education processes from the school to the community; particularly, when formal systems exclude Indigenous cultures and languages. Based on ethnographic…

Sumida Huaman, Elizabeth; Valdiviezo, Laura Alicia

2014-01-01

95

Alien encounters and the alien\\/human dichotomy in Stanley Kubrick's 2001, a space odyssey and Andrei Tarkovsky's Solaris  

Microsoft Academic Search

The alien encounter has long been a defining and popular subject of science fiction cinema. However, Stanley Kubrick's 2001: A Space Odyssey (1968) and Andrei Tarkovsky's Solaris (1972) are interrogative, complex, and distinct artistic accomplishments that stand apart from and above the conventional science fiction film. 2001 and Solaris not only represent but complicate the alien\\/human dichotomy; in the end,

Keith Cavedo

2010-01-01

96

Components of Candidate Images: Statistical Analysis of the Issue-Persona Dichotomy in the Presidential Campaign of 1996.  

ERIC Educational Resources Information Center

Describes the results of a study intended to test a specific hypothesis and a research question related to the theoretical development of the candidate image construct in political communication. Tests the long-standing assumption that there is a dichotomy between candidate issue positions and candidate persona impressions ("images"). Finds no…

Hacker, Kenneth L.; Zakahi, Walter R.; Giles, Maury J.; McQuitty, Shaun

2000-01-01

97

A Diurnal Dichotomy in Venus Upper Atmospheric Circulation: June 2012 Solar Transit Observations  

NASA Astrophysics Data System (ADS)

We obtained sub-millimeter line absorption spectra of 12CO (346 gHz) and 13CO (330 gHz) around the atmospheric limb of Venus; as illuminated by the Sun during the June 5, 2012 solar transit, and as observed from the James Clerk Maxwell Telescope (JCMT) on Mauna Kea, Hawaii. Doppler line shifts retrieved around the Venus atmospheric limb, associated with upper mesospheric/lower thermospheric (90-115 km) winds, indicate strong axis-symmetric subsolar-to-antisolar (SSAS) circulation across the circumdisk terminator of Venus. This SSAS circulation contrasts with the full nightside circulation revealed by on-disk Doppler wind measurements, obtained before, during, and after solar transit, that indicate a strong retrograde zonal wind component. These unique Venus solar transit observations thus demonstrate a striking dichotomy in the dayside and nightside circulations of the Venus upper atmosphere.

Clancy, R. T.; Sandor, B. J.; Hoge, J.

2012-10-01

98

Examining the Radio-loud/Radio-quiet Dichotomy with New Chandra and VLA Observations of 13 UGC Galaxies  

NASA Astrophysics Data System (ADS)

We present the results from new ~15 ks Chandra-ACIS and 4.9 GHz Very Large Array (VLA) observations of 13 galaxies hosting low-luminosity active galactic nuclei (AGNs). This completes the multiwavelength study of a sample of 51 nearby early-type galaxies described in Capetti & Balmaverde and Balmaverde & Capetti. The aim of the three previous papers was to explore the connection between the host galaxies and AGN activity in a radio-selected sample. We detect nuclear X-ray emission in eight sources and radio emission in all but one (viz., UGC 6985). The new VLA observations improve the spatial resolution by a factor of 10: the presence of nuclear radio sources in 12 of the 13 galaxies confirms their AGN nature. As previously indicated, the behavior of the X-ray and radio emission in these sources depends strongly on the form of their optical surface brightness profiles derived from Hubble Space Telescope imaging, i.e., on their classification as "core," "power-law," or "intermediate" galaxies. With more than twice the number of "power-law" and "intermediate" galaxies compared to previous work, we confirm with a much higher statistical significance that these galaxies lie well above the radio-X-ray correlation established in Fanaroff-Riley type I radio galaxies and the low-luminosity "core" galaxies. This result highlights the fact that the "radio-loud/radio-quiet" dichotomy is a function of the host galaxy's optical surface brightness profile. We present radio-optical-X-ray spectral indices for all 51 sample galaxies. Survival statistics point to significant differences in the radio-to-optical and radio-to-X-ray spectral indices between the "core" and "power-law" galaxies (Gehan's Generalized Wilcoxon test probability p for the two classes being statistically similar is <10-5), but not in the optical-to-X-ray spectral indices (p = 0.25). Therefore, the primary difference between the "core" and "power-law" galaxies is in their ability to launch powerful radio outflows. This result is consistent with the hypothesis of different formation processes and evolution histories in "core" and "power-law" galaxies: major mergers are likely to have created "core" galaxies, while minor mergers were instrumental in the creation of "power-law" galaxies.

Kharb, P.; Capetti, A.; Axon, D. J.; Chiaberge, M.; Grandi, P.; Robinson, A.; Giovannini, G.; Balmaverde, B.; Macchetto, D.; Montez, R.

2012-04-01

99

EXAMINING THE RADIO-LOUD/RADIO-QUIET DICHOTOMY WITH NEW CHANDRA AND VLA OBSERVATIONS OF 13 UGC GALAXIES  

SciTech Connect

We present the results from new {approx}15 ks Chandra-ACIS and 4.9 GHz Very Large Array (VLA) observations of 13 galaxies hosting low-luminosity active galactic nuclei (AGNs). This completes the multiwavelength study of a sample of 51 nearby early-type galaxies described in Capetti and Balmaverde and Balmaverde and Capetti. The aim of the three previous papers was to explore the connection between the host galaxies and AGN activity in a radio-selected sample. We detect nuclear X-ray emission in eight sources and radio emission in all but one (viz., UGC 6985). The new VLA observations improve the spatial resolution by a factor of 10: the presence of nuclear radio sources in 12 of the 13 galaxies confirms their AGN nature. As previously indicated, the behavior of the X-ray and radio emission in these sources depends strongly on the form of their optical surface brightness profiles derived from Hubble Space Telescope imaging, i.e., on their classification as 'core', 'power-law', or 'intermediate' galaxies. With more than twice the number of 'power-law' and 'intermediate' galaxies compared to previous work, we confirm with a much higher statistical significance that these galaxies lie well above the radio-X-ray correlation established in Fanaroff-Riley type I radio galaxies and the low-luminosity 'core' galaxies. This result highlights the fact that the 'radio-loud/radio-quiet' dichotomy is a function of the host galaxy's optical surface brightness profile. We present radio-optical-X-ray spectral indices for all 51 sample galaxies. Survival statistics point to significant differences in the radio-to-optical and radio-to-X-ray spectral indices between the 'core' and 'power-law galaxies (Gehan's Generalized Wilcoxon test probability p for the two classes being statistically similar is <10{sup -5}), but not in the optical-to-X-ray spectral indices (p = 0.25). Therefore, the primary difference between the 'core' and 'power-law' galaxies is in their ability to launch powerful radio outflows. This result is consistent with the hypothesis of different formation processes and evolution histories in 'core' and 'power-law' galaxies: major mergers are likely to have created 'core' galaxies, while minor mergers were instrumental in the creation of 'power-law' galaxies.

Kharb, P.; Axon, D. J.; Robinson, A. [Physics Department, Rochester Institute of Technology, Rochester, NY 14623 (United States); Capetti, A.; Balmaverde, B. [INAF, Osservatorio Astronomico di Torino, Strada Osservatorio 20, 10025 Pino Torinese (Italy); Chiaberge, M.; Macchetto, D. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Grandi, P. [INAF, Istituto di Astrofisica Spaziale e Fisica Cosmica, Bologna (Italy); Giovannini, G. [INAF, Istituto di Radioastronomia di Bologna, via Gobetti 101, 40129 Bologna (Italy); Montez, R., E-mail: kharb@cis.rit.edu [Center for Imaging Science, Rochester Institute of Technology, Rochester, NY 14623 (United States)

2012-04-15

100

EMBRYO IMPACTS AND GAS GIANT MERGERS. I. DICHOTOMY OF JUPITER AND SATURN's CORE MASS  

SciTech Connect

Interior to the gaseous envelopes of Saturn, Uranus, and Neptune, there are high-density cores with masses larger than 10 Earth masses. According to the conventional sequential accretion hypothesis, such massive cores are needed for the onset of efficient accretion of their gaseous envelopes. However, Jupiter's gaseous envelope is more massive and its core may be less massive than those of Saturn. In order to account for this structural diversity and the super-solar metallicity in the envelope of Jupiter and Saturn, we investigate the possibility that they may have either merged with other gas giants or consumed several Earth-mass protoplanetary embryos during or after the rapid accretion of their envelope. In general, impinging sub-Earth-mass planetesimals disintegrate in gas giants' envelopes, deposit heavy elements well outside the cores, and locally suppress the convection. Consequently, their fragments sediment to promote the growth of cores. Through a series of numerical simulations, we show that it is possible for colliding super-Earth-mass embryos to reach the cores of gas giants. Direct parabolic collisions also lead to the coalescence of gas giants and merging of their cores. In these cases, the energy released from the impact leads to vigorous convective motion throughout the envelope and the erosion of the cores. This dichotomy contributes to the observed dispersion in the internal structure and atmospheric composition between Jupiter and Saturn and other gas giant planets and elsewhere.

Li Shulin [Department of Astronomy, Kavli Institute of Astronomy and Astrophysics, Peking University, Beijing (China); Agnor, C.B. [Astronomy Unit, School of Mathematical Sciences, Queen Mary University of London (United Kingdom); Lin, D. N. C. [Department of Astronomy and Astrophysics, University of California Santa Cruz (United States)

2010-09-10

101

Illumination of Parainfluenza Virus Infection and Transmission in Living Animals Reveals a Tissue-Specific Dichotomy  

PubMed Central

The parainfluenza viruses (PIVs) are highly contagious respiratory paramyxoviruses and a leading cause of lower respiratory tract (LRT) disease. Since no vaccines or antivirals exist, non-pharmaceutical interventions are the only means of control for these pathogens. Here we used bioluminescence imaging to visualize the spatial and temporal progression of murine PIV1 (Sendai virus) infection in living mice after intranasal inoculation or exposure by contact. A non-attenuated luciferase reporter virus (rSeV-luc(M-F*)) that expressed high levels of luciferase yet was phenotypically similar to wild-type Sendai virus in vitro and in vivo was generated to allow visualization. After direct intranasal inoculation, we unexpectedly observed that the upper respiratory tract (URT) and trachea supported robust infection under conditions that result in little infection or pathology in the lungs including a low inoculum of virus, an attenuated virus, and strains of mice genetically resistant to lung infection. The high permissivity of the URT and trachea to infection resulted in 100% transmission to naïve contact recipients, even after low-dose (70 PFU) inoculation of genetically resistant BALB/c donor mice. The timing of transmission was consistent with the timing of high viral titers in the URT and trachea of donor animals but was independent of the levels of infection in the lungs of donors. The data therefore reveals a disconnect between transmissibility, which is associated with infection in the URT, and pathogenesis, which arises from infection in the lungs and the immune response. Natural infection after transmission was universally robust in the URT and trachea yet limited in the lungs, inducing protective immunity without weight loss even in genetically susceptible 129/SvJ mice. Overall, these results reveal a dichotomy between PIV infection in the URT and trachea versus the lungs and define a new model for studies of pathogenesis, development of live virus vaccines, and testing of antiviral therapies. PMID:21750677

Surman, Sherri L.; Jones, Bart G.; Dalloneau, Emilie; Hurwitz, Julia L.; Russell, Charles J.

2011-01-01

102

Three-dimensional simulations of the southern polar giant impact hypothesis for the origin of the Martian dichotomy  

NASA Astrophysics Data System (ADS)

We demonstrate via numerical simulations that the impact of a ~lunar-sized body with Mars is capable of creating a hemispherical magma ocean that upon cooling and solidification resulted in the formation of the southern highlands and thus the Martian dichotomy. The giant impact may have contributed a significant amount of iron to the Martian core and generated a deep thermal anomaly that led to the onset and development of the volcanism in the southern highlands. Our model predicts several mantle plumes converging to the South Pole from the equatorial regions as well as new plumes forming in the equatorial region and also an absence of significant large-scale volcanism in the northern lowlands. The core heat flux evolution obtained from our numerical models is consistent with the decline of the magnetic field. We argue that such a scenario is more consistent with a range of observations than a northern giant impact (excavating the Borealis basin) for the formation of the Martian dichotomy.

Leone, Giovanni; Tackley, Paul J.; Gerya, Taras V.; May, Dave A.; Zhu, Guizhi

2014-12-01

103

DISCLOSING THE RADIO LOUDNESS DISTRIBUTION DICHOTOMY IN QUASARS: AN UNBIASED MONTE CARLO APPROACH APPLIED TO THE SDSS-FIRST QUASAR SAMPLE  

SciTech Connect

We investigate the dichotomy in the radio loudness distribution of quasars by modeling their radio emission and various selection effects using a Monte Carlo approach. The existence of two physically distinct quasar populations, the radio-loud and radio-quiet quasars, is controversial and over the last decade a bimodal distribution of radio loudness of quasars has been both affirmed and disputed. We model the quasar radio luminosity distribution with simple unimodal and bimodal distribution functions. The resulting simulated samples are compared to a fiducial sample of 8300 quasars drawn from the SDSS DR7 Quasar Catalog and combined with radio observations from the FIRST survey. Our results indicate that the SDSS-FIRST sample is best described by a radio loudness distribution which consists of two components, with (12 {+-} 1)% of sources in the radio-loud component. On the other hand, the evidence for a local minimum in the loudness distribution (bimodality) is not strong and we find that previous claims for its existence were probably affected by the incompleteness of the FIRST survey close to its faint limit. We also investigate the redshift and luminosity dependence of the radio loudness distribution and find tentative evidence that at high redshift radio-loud quasars were rarer, on average louder, and exhibited a smaller range in radio loudness. In agreement with other recent work, we conclude that the SDSS-FIRST sample strongly suggests that the radio loudness distribution of quasars is not a universal function, and that more complex models than presented here are needed to fully explain available observations.

Balokovic, M. [Department of Astronomy, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Smolcic, V. [Argelander-Institut fuer Astronomie, Auf dem Hugel 71, D-53121 Bonn (Germany); Ivezic, Z. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Zamorani, G. [INAF-Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Schinnerer, E. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Kelly, B. C. [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106 (United States)

2012-11-01

104

Disclosing the Radio Loudness Distribution Dichotomy in Quasars: An Unbiased Monte Carlo Approach Applied to the SDSS-FIRST Quasar Sample  

NASA Astrophysics Data System (ADS)

We investigate the dichotomy in the radio loudness distribution of quasars by modeling their radio emission and various selection effects using a Monte Carlo approach. The existence of two physically distinct quasar populations, the radio-loud and radio-quiet quasars, is controversial and over the last decade a bimodal distribution of radio loudness of quasars has been both affirmed and disputed. We model the quasar radio luminosity distribution with simple unimodal and bimodal distribution functions. The resulting simulated samples are compared to a fiducial sample of 8300 quasars drawn from the SDSS DR7 Quasar Catalog and combined with radio observations from the FIRST survey. Our results indicate that the SDSS-FIRST sample is best described by a radio loudness distribution which consists of two components, with (12 ± 1)% of sources in the radio-loud component. On the other hand, the evidence for a local minimum in the loudness distribution (bimodality) is not strong and we find that previous claims for its existence were probably affected by the incompleteness of the FIRST survey close to its faint limit. We also investigate the redshift and luminosity dependence of the radio loudness distribution and find tentative evidence that at high redshift radio-loud quasars were rarer, on average louder, and exhibited a smaller range in radio loudness. In agreement with other recent work, we conclude that the SDSS-FIRST sample strongly suggests that the radio loudness distribution of quasars is not a universal function, and that more complex models than presented here are needed to fully explain available observations.

Balokovi?, M.; Smol?i?, V.; Ivezi?, Ž.; Zamorani, G.; Schinnerer, E.; Kelly, B. C.

2012-11-01

105

Current Biology 16, 990995, May 23, 2006 2006 Elsevier Ltd All rights reserved DOI 10.1016/j.cub.2006.03.063 Phenotypically Linked Dichotomy  

E-print Network

dramatic ontogenic changes in body size and behavior, with the loggerhead sea turtle, Caretta caretta.cub.2006.03.063 Report Phenotypically Linked Dichotomy in Sea Turtle Foraging Requires Multiple a million square kilometers. Therefore, mitigation of fisheries by-catch for sea turtles in the east

Exeter, University of

106

Individuality beyond the Dichotomy of "Small Self and Big Self" in Contemporary Chinese Education: Lessons from Hu Shi and Liang Shuming  

ERIC Educational Resources Information Center

This article identifies the problem that an instrumentalist mode of thinking dominates China's contemporary education practice and suggests that the dichotomy between the "small self and big self," a notion that has been present throughout modern Chinese history, exacerbates this instrumentalism. It parallels the loss of…

Zhang, Huajun

2013-01-01

107

Probing The Causes of the High/Low Jet Power Dichotomy in AGN Jets with Chandra and HST  

NASA Astrophysics Data System (ADS)

We propose for deep Chandra-HST observations of 3 hybrid MOJAVE quasars. As these sources have jets with different powers {Fanaroff-Riley type I & II} on either side of the central engine they could be the touchstone for ideas put forth to explain the question of the FR dichotomy and the nature of AGN jets in general. These deep observations will constrain unambiguously the X-ray emission mechanisms in these jets through the construction and modeling of broad-band SEDs at multiple jet positions. The X-ray imaging may reveal asymmetries in the hot gas on either side of the AGN, telling us about jet propagation in low/high power sources. The lack of such features may provide support to the idea of highly magnetized jets, which could be examined further through broad-band SED modeling.

Kharb, Preeti

2012-10-01

108

Probing The Causes of the High/Low Jet Power Dichotomy in AGN Jets with Chandra and HST  

NASA Astrophysics Data System (ADS)

We propose for deep Chandra-HST observations of 3 hybrid MOJAVE quasars. As these sources have jets with different powers (Fanaroff-Riley type I & II) on either side of the central engine they could be the touchstone for ideas put forth to explain the question of the FR dichotomy and the nature of AGN jets in general. These deep observations will constrain unambiguously the X-ray emission mechanisms in these jets through the construction and modeling of broad-band SEDs at multiple jet positions. The X-ray imaging may reveal asymmetries in the hot gas on either side of the AGN, telling us about jet propagation in low/high power sources. The lack of such features may provide support to the idea of highly magnetized jets, which could be examined further through broad-band SED modeling.

Kharb, Preeti

2012-09-01

109

Fire-mediated disruptive selection can explain the reseeder-resprouter dichotomy in Mediterranean-type vegetation.  

PubMed

Crown fire is a key selective pressure in Mediterranean-type plant communities. Adaptive responses to fire regimes involve trade-offs between investment for persistence (fire survival and resprouting) and reproduction (fire mortality, fast growth to reproductive maturity, and reseeding) as investments that enhance adult survival lower growth and reproductive rates. Southern hemisphere Mediterranean-type ecosystems are dominated by species with either endogenous regeneration from adult resprouting or fire-triggered seedling recruitment. Specifically, on nutrient-poor soils, these are either resprouting or reseeding life histories, with few intermediate forms, despite the fact that the transition between strategies is evolutionarily labile. How did this strong dichotomy evolve? We address this question by developing a stochastic demographic model to assess determinants of relative fitness of reseeders, resprouters and hypothetical intermediate forms. The model was parameterised using published demographic data from South African protea species and run over various relevant fire regime parameters facets. At intermediate fire return intervals, trade-offs between investment in growth versus fire resilience can cause fitness to peak at either of the extremes of the reseeder-resprouter continuum, especially when assuming realistic non-linear shapes for these trade-offs. Under these circumstances, the fitness landscape exhibits a saddle which could lead to disruptive selection. The fitness gradient between the peaks was shallow, which may explain why this life-history trait is phylogenetically labile. Resprouters had maximum fitness at shorter fire-return intervals than reseeders. The model suggests that a strong dichotomy in fire survival strategy depends on a non-linear trade-off between growth and fire persistence traits. PMID:25348575

Altwegg, Res; De Klerk, Helen M; Midgley, Guy F

2015-02-01

110

EVERY BCG WITH A STRONG RADIO AGN HAS AN X-RAY COOL CORE: IS THE COOL CORE-NONCOOL CORE DICHOTOMY TOO SIMPLE?  

SciTech Connect

The radio active galactic nucleus (AGN) feedback in X-ray cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong radio AGNs also exist in 'noncool core' clusters, which brings up the question whether an X-ray cool core is always required for the radio feedback. In this work, we present a systematic analysis of brightest cluster galaxies (BCGs) and strong radio AGNs in 152 groups and clusters from the Chandra archive. All 69 BCGs with radio AGN more luminous than 2 x 10{sup 23} W Hz{sup -1} at 1.4 GHz are found to have X-ray cool cores. BCG cool cores can be divided into two classes: the large cool core (LCC) class and the corona class. Small coronae, easily overlooked at z > 0.1, can trigger strong heating episodes in groups and clusters, long before LCCs are formed. Strong radio outbursts triggered by coronae may destroy embryonic LCCs and thus provide another mechanism to prevent the formation of LCCs. However, it is unclear whether coronae are decoupled from the radio feedback cycles as they have to be largely immune to strong radio outbursts. Our sample study also shows the absence of groups with a luminous cool core while hosting a strong radio AGN, which is not observed in clusters. This points to a greater impact of radio heating on low-mass systems than clusters. Few L {sub 1.4GHz} > 10{sup 24} W Hz{sup -1} radio AGNs (approx16%) host an L {sub 0.5-10keV} > 10{sup 42} erg s{sup -1} X-ray AGN, while above these thresholds, all X-ray AGNs in BCGs are also radio AGNs. As examples of the corona class, we also present detailed analyses of a BCG corona associated with a strong radio AGN (ESO 137-006 in A3627) and one of the faintest coronae known (NGC 4709 in the Centaurus cluster). Our results suggest that the traditional cool core/noncool core dichotomy is too simple. A better alternative is the cool core distribution function, with the enclosed X-ray luminosity or gas mass.

Sun, M., E-mail: msun@virginia.ed [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States)

2009-10-20

111

Disorders of Thought Are Severe Mood Disorders: the Selective Attention Defect in Mania Challenges the Kraepelinian Dichotomy—A Review  

PubMed Central

Kraepelin said severe mental illness was due to 2 diseases subsequently characterized as disorders of thought vs disorders of mood, ie, the Kraepelinian dichotomy. Schizophrenia, traditionally considered the disorder of thought, has been defined by the presence of hallucinations, delusions, catatonia, and disorganization. Tangentiality, derailment, loose associations, and thought blocking are typically considered pathognomonic of schizophrenia. By contrast, the mood disorders have been characterized only as disorders of the emotions, though both depression and mania, when severe, are now recognized to include the same psychotic features traditionally considered diagnostic of schizophrenia. This article addresses disordered thinking in mania in order to clarify the relationship between schizophrenia and psychotic mood disorders. Normally, the brain's selective attention mechanism filters and prioritizes incoming stimuli by excluding from consciousness extraneous, low-priority stimuli and grading the importance of more relevant data. Because this “filter/prioritizer” becomes defective in mania, tangential stimuli are processed without appropriate prioritization. Observed as distractibility, this symptom is an index of the breakdown in selective attention and the severity of mania, accounting for the signs and symptoms of psychotic thinking. The zone of rarity between schizophrenia and psychotic mood disorders is blurred because severe disorders of mood are also disorders of thought. This relationship calls into question the tenet that schizophrenia is a disease separate from psychotic mood disorders. Patients whose case histories are discussed herein gave their written informed consent to participate in this institutional human subjects committee–approved protocol. PMID:17515440

Raymond Lake, C.

2008-01-01

112

A dichotomy in the orientation of dust and radio jets in nearby low-power radio galaxies  

E-print Network

We examine the properties of central dust in nearby quiescent and active early-type galaxies. The active galaxies are low-power radio galaxies with Fanaroff & Riley Type I or I/II radio jets. We focus on the comparison of the dust distributions in the active and quiescent galaxy samples and the relation between the radio jet and dust orientations. Our main observational conclusions are: (a) radio galaxies contain a higher fraction of regular dust 'ellipses' compared to quiescent galaxies which contain more often irregular dust distributions; (b) the morphology, size and orientation of dust ellipses and lanes in quiescent early-types and active early-types with kpc-scale radio jets is very similar; (c) dust ellipses are aligned with the major axis of the galaxy, dust lanes do not show a preferred alignment except for large (>kpc) dust lanes which are aligned with the minor axis of the galaxy. Dust morphologies can be classified as regular 'ellipses' and filamentary 'lanes'. We show that the dust ellipses are consistent with being nearly circular thin disks viewed at random viewing angles. The lanes are likely warped dust structures, which may be in the process of settling down to become regular disks or are being perturbed by a non-gravitational force. We use the observed dust-jet orientations to constrain the three-dimensional angle $\\theta_{\\rm DJ}$ between jet and dust. For dust-lane galaxies, the jet is approximately perpendicular to the dust structure, while for dust-ellipse galaxies there is a much wider distribution of $\\theta_{\\rm DJ}$. We discuss two scenarios that could explain the dust/jet/galaxy orientation dichotomy. (abridged)

Gijs Verdoes Kleijn; Tim de Zeeuw

2005-02-03

113

Volume-limited SDSS/FIRST quasars and the radio dichotomy  

E-print Network

Much evidence has been presented in favor of and against the existence of two distinct populations of quasars, radio-loud and radio-quiet. The SDSS differs from earlier optically selected quasar surveys in the large number of quasars and the targeting of FIRST radio source counterparts as quasar candidates. This allows a qualitatively different approach of constructing a series of samples at different redshifts which are volume-limited with respect to both radio and optical luminosity. This technique avoids any biases from the strong evolution of quasar counts with redshift and potential redshift-dependent selection effects. We find that optical and radio luminosities of quasars detected in both SDSS and FIRST are not well correlated within each redshift shell, although the fraction of radio detections among optically selected quasars remains roughly constant at 10% for z <= 3.2. The distribution in the luminosity-luminosity plane does not appear to be strongly bimodal. The optical luminosity function is marginally flatter at higher radio luminosities.

S. Jester; R. Kron

2003-10-22

114

Lineated valley fill (LVF) and lobate debris aprons (LDA) in the Deuteronilus Mensae northern dichotomy boundary region, Mars: Constraints on the extent, age and episodicity of Amazonian glacial events  

NASA Astrophysics Data System (ADS)

In order to assess the nature, degradational processes and history of the dichotomy boundary on Mars, we conducted a detailed morphological analysis of a 70,000 km 2 region of its northern portion (north-central Deuteronilus Mensae, south of Lyot, in the vicinity of Sinton Crater). This region is characterized by the distinctive sinuous ˜2 km-high plateau scarp boundary, outlying massifs to the north, and extensive fretted valleys dissecting the plateau to the south. These features represent the first-order modification and retreat of the dichotomy boundary, and are further modified by processes that form lineated valley fill (LVF) in the fretted valleys, and lobate debris aprons (LDA) along the dichotomy scarp and surrounding the outlying massifs. We use new high-resolution image and topography data to examine the nature and origin of LVF and LDA and to investigate the climatic and accompanying degradational history of the escarpment. On the basis of our analysis, we conclude that: (1) LVF and LDA deposits within the study region are comprised of the same material, show integrated flow patterns, and originate as debris-covered valley glaciers; a significant amount of ice (hundreds of meters) is likely to remain today beneath a thin cover of sublimation till. (2) There is depositional evidence to suggest glacial highstands at least 800 m above the present level, implying previous conditions in which the distribution of ice was much more widespread; this is supported by similar deposits within many other areas across the dichotomy boundary. (3) The timing of the most recent large-scale activity of the LDA/LVF in this area is about 100-500 million years ago, similar to ages reported elsewhere along the dichotomy boundary. (4) There is evidence for a secondary, but significantly limited phase of glaciation; the deposits of which are limited to the vicinity of the alcoves; similar later phases have also been reported elsewhere along the dichotomy boundary. (5) Modification of the fretted valleys of the dichotomy boundary has been substantial locally, but we find no evidence that the Amazonian glacial epochs caused retreat of the dichotomy boundary of the scale of tens to hundreds of kilometers. Our findings support the results of an analysis just to the east of the study region and of studies carried out elsewhere along the dichotomy boundary that find further evidence for the remnants of debris-covered glaciers and extensive valley glacial land systems.

Morgan, Gareth A.; Head, James W.; Marchant, David R.

2009-07-01

115

Kraepelin's dichotomy is true: contrasting brain dysfunction at the extremes of human growth and maturation. Excitability, the fundamental property of nervous tissue, is affected.  

PubMed

The distribution of Kraepelin's ubiquitous dichotomy varies with standard of living and pubertal age: when one rises, the other declines. The universal similar clinical picture--mortality risk, manic depressive psychosis, episodic dysfunction of brainstem control systems (sleep-wake cycle, food, mood control mechanism)--is caused by abridged pubertal pruning of excitatory synapses, which is treated with anti-epileptics, as opposed to convulsant neuroleptics in dementia praecox, where the clinical variation reflects varying degrees of excessive pruning and deficit in excitability. Localization of cortical breakdown of circuitry, silent spots and persistent dysfunction due to insufficient fill-in mechanisms, determine the clinical picture. This ranges from dementia praecox in late puberty and poor living standards, to cognitive dysfunction (mainly with higher standards of living) with earlier puberty. This variation is the most likely explanation why the acceptance of dementia praecox as a disease entity was complicated. Kraepelin's dichotomy, episodic dysfunction against a clinical deterioration, is at the extremes of brain maturation; the fundamental property of nervous tissue, excitability, is affected. To reduce the risk of psychotic episodes, omega-3 might also be given, as it normalizes excitation at all levels. The neo-Kraepelinian atheoretical quantitative scoring systems have eliminated disease entities and neglected endogeneity in psychiatry. We are back to a pre-Kraepelinian state, without his systematic observations. What is psychiatry without Kraepelin's dichotomy? Mood stability is a fundamental personality trait with a normal distribution; what is considered within or outside normal variation is arbitrary. Given the mood-stabilizing effect of anti-epileptics and omega-3, these will increasingly dominate psychiatric treatment. PMID:17886163

Saugstad, Letten F

2009-01-01

116

The Relationship Among Foot Posture, Core and Lower Extremity Muscle Function, and Postural Stability  

PubMed Central

Context: Identification of impaired balance as a risk factor for lower extremity injury regardless of injury history has led to subsequent investigation of variables that may adversely affect balance in healthy individuals. Objectives: To investigate the relationship among core and lower extremity muscle function, foot posture, and balance. Design: Descriptive laboratory study. Setting: Musculoskeletal injury biomechanics laboratory. Patients or Other Participants: A total of 108 individuals (40 men, 68 women; age = 22.8 ± 4.7 years, height = 168.5 ± 10.4 cm, mass = 69.9 ± 13.3 kg) participated in the study. Main Outcome Measure(s): Core endurance was assessed during 1 time-to-failure trial, and isometric hip and ankle strength were assessed using a handheld dynamometer and isokinetic dynamometer, respectively. Foot structure was quantified using the digital photographic measurement method. Single-limb–stance time to boundary was assessed using a force plate during an eyes-closed condition. Hierarchical multiple regression analyses were performed to predict balance using lower extremity strength, foot posture, and core endurance. Results: Foot posture (? = ?0.22, P = .03) and ankle-inversion strength (? = ?0.29, P = .006) predicted mediolateral balance. Increasing arch posture and ankle-inversion strength were associated with decreased mediolateral single-limb–stance balance. Conclusions: Increasing arch height was associated with decreased mediolateral control of single-limb stance. The relationship between time to boundary and injury risk, however, has not been explored. Therefore, the relationship between increasing arch height and injury due to postural instability cannot be determined from this study. If authors of future prospective studies identify a relationship between decreased time to boundary and increased injury risk, foot structure may be an important variable to assess during preparticipation physical examinations. The relationship between increasing ankle-inversion strength and decreased balance may require additional study to further elucidate the relationship between ankle strength and balance. PMID:24568226

Cobb, Stephen C.; Bazett-Jones, David M.; Joshi, Mukta N.; Earl-Boehm, Jennifer E.; James, C. Roger

2014-01-01

117

Evolution of the Martian Highlands along the Dichotomy Boundary: Geologic Mapping of the Deuteronilus Mensae Region, Mars  

NASA Astrophysics Data System (ADS)

Deuteronilus Mensae, a gradational boundary zone in the northern mid-latitudes of Mars, includes the transition from the rugged cratered highlands and polygonal mesas of Arabia Terra to the northern lowlands of Acidalia Planitia. Within this zone, features diagnostic of Martian 'fretted' terrain are observed, including numerous lobate debris aprons. The concentration of aprons indicate that ground ice was, or still is present, which is of great interest because of their potential association with changes in Martian climate. North of the boundary zone are the northern lowlands, a depositional sink that perhaps was once filled by large standing bodies of water. The lowlands have surface elevations that are several kilometers below the ancient highlands with significantly younger surface ages. To better understand the geologic evolution of the Arabia Terra highlands, we have mapped the geology of a north-south transect across the Martian dichotomy boundary from 32.5 N to 47.5 N and 20-25 E. To the south, the ancient highland plateau has been modified by subsurface volatile activity, causing surface collapse and the formation of numerous elongated closed depressions containing blocks of the pre-existing surface. Parts of the plateau have also been dissected by fluvial channels that may have formed by sapping processes or short- lived precipitation-derived overland flow. In the central portion of the map area, the preserved highlands transition to individual mesas with tops that have a similar morphology to the continuous plateau. Below highland escarpments and mesa walls, lobate debris aprons have surface lineations and deflected margins indicating flow of volatile-rich materials. Fretted valleys appear to originate at the highland margin and develop by backwasting of plateau materials. In this central area, we did not find any distinct geomorphologic features related to coastal processes that would support the hypothesis of an ancient lowland ocean. To the north, within areas of smooth and knobby plains, clusters of small mesas and knobs are surrounded by debris aprons. Mesa tops gradually decrease in elevation towards the north and their surfaces are sometimes covered by mantling deposits. Two mesa-forming units with tops at consistently different surface elevations suggest a regional stratigraphic sequence of less-resistant upper mesa materials overlying more-resistant lower mesa materials. Preliminary crater retention age ranges from Viking data are Early-to-Mid Noachian for plateau materials, Early-to-Mid Noachian for dissected plateau materials, and Late Noachian to Early Hesperian for smooth plains materials.

Chuang, F. C.; Crown, D. A.

2006-12-01

118

Relative Ages of the Highlands, Lowlands, and Transition Zone Along a Portion of the Mars Crustal Dichotomy from Densities of Visible and Buried Impact Craters  

NASA Technical Reports Server (NTRS)

Understanding the fundamental age relationships of the different parts of the Mars Crustal Dichotomy is essential to fully understanding the events that shaped the early history and formation of the surface of Mars. A dominant question is what are the true relative ages of the Northern Lowlands and the Southern Highlands? Using MOLA data from the Mars Global Surveyor and Viking visual images, a dataset of both buried and visible crater diameters was created over a nine million sq km study area of a section of the dichotomy boundary stretching from Arabia Terra to Utopia Planitia. Cumulative frequency plots on a log-log scale were used to determine the relative ages for the Highlands, the Lowlands, and the Transition Zone, separately for the visible, the buried and the combined total (visible+ buried) populations. We find the overall Highland crater population in this area is slightly older than the Lowlands, consistent with previous global studies, but the Lowlands and Transition Zone are also very old and formed at roughly the same time. It appears that the formation of the Lowlands in this region formed contemporaneously with a large-scale resurfacing event in the Highlands, perhaps caused by the process responsible for the Lowland formation.

DeSoto, G. E.; Frey, H. V.

2005-01-01

119

Lineated valley fill and lobate debris apron stratigraphy in Nilosyrtis Mensae, Mars: Evidence for phases of glacial modification of the dichotomy boundary  

NASA Astrophysics Data System (ADS)

The Nilosyrtis Mensae region is important among dichotomy boundary fretted terrain outcrops, as it provides evidence of overprinting of ancient landscapes by a suite of glacial features, providing a composite view of the variety of midlatitude glacial modification processes that can occur during recent Martian ice ages. On the basis of a series of criteria developed for the identification of a glacial origin for lineated valley fill and lobate debris aprons, we interpret stratigraphic, topographic, and textural relationships between lineated valley fill and lobate debris apron morphological units as evidence of local and regional glacial overprinting of the landscape during the recent Amazonian. We document (1) stratigraphic relationships between lineated valley fill subunits, including the presence of apparently superposed and small-scale lobate features, (2) the regional integration and flow of lineated valley fill material, (3) lineated valley fill degradation, and (4) the nature and stratigraphic position of lobate debris aprons. These observations suggest multiple phases or episodes of midlatitude valley glacier activity. These observations, together with those of surface units elsewhere in northern Arabia Terra interpreted as glacially modified landforms, suggest the possibility of midlatitude glacial deposits extending over broad portions of the Martian dichotomy boundary within the past several hundred million years.

Levy, Joseph S.; Head, James W.; Marchant, David R.

2007-08-01

120

Effect of postural insoles on static and functional balance in children with cerebral palsy: A randomized controlled study  

PubMed Central

BACKGROUND: Improved gait efficiency is one of the goals of therapy for children with cerebral palsy (CP). Postural insoles can allow more efficient gait by improving biomechanical alignment. OBJECTIVE: The aim of the present study was to determine the effect of the combination of postural insoles and ankle-foot orthoses on static and functional balance in children with CP. METHOD: A randomized, controlled, double-blind, clinical trial. After meeting legal requirements and the eligibility criteria, 20 children between four and 12 years of age were randomly allocated either to the control group (CG) (n=10) or the experimental group (EG) (n=10). The CG used placebo insoles and the EG used postural insoles. The Berg Balance Scale, Timed Up-and-Go Test, Six-Minute Walk Test, and Gross Motor Function Measure-88 were used to assess balance as well as the determination of oscillations from the center of pressure in the anteroposterior and mediolateral directions with eyes open and closed. Three evaluations were carried out: 1) immediately following placement of the insoles; 2) after three months of insole use; and 3) one month after suspending insole use. RESULTS: The EG achieved significantly better results in comparison to the CG on the Timed Up-and-Go Test as well as body sway in the anteroposterior and mediolateral directions. CONCLUSION: Postural insoles led to an improvement in static balance among children with cerebral palsy, as demonstrated by the reduction in body sway in the anteroposterior and mediolateral directions. Postural insole use also led to a better performance on the Timed Up-and-Go Test. PMID:25651134

Christovão, Thaluanna C. L.; Pasini, Hugo; Grecco, Luanda A. C.; Ferreira, Luiz A. B.; Duarte, Natália A. C.; Oliveira, Cláudia S.

2015-01-01

121

Photometric properties of Titan's surface from Cassini VIMS: Relevance to titan's hemispherical albedo dichotomy and surface stability  

USGS Publications Warehouse

The Visual and Infrared Mapping Spectrometer (VIMS) instrument on the Cassini Saturn Orbiter returned spectral imaging data as the spacecraft undertook six close encounters with Titan beginning 7 July, 2004. Three of these flybys each produced overlapping coverage of two distinct regions of Titan's surface. Twenty-four points were selected on approximately opposite hemispheres to serve as photometric controls. Six points were selected in each of four reflectance classes. On one hemisphere each control point was observed at three distinct phase angles. From the derived phase coefficients, preliminary normal reflectances were derived for each reflectance class. The normal reflectance of Titan's surface units at 2.0178 ??m ranged from 0.079 to 0.185 for the most absorbing to the most reflective units assuming no contribution from absorbing haze. When a modest haze contribution of ??=0.1 is considered these numbers increase to 0.089-0.215. We find that the lowest three reflectance classes have comparable normal reflectance on either hemisphere. However, for the highest brightness class the normal reflectance is higher on the hemisphere encompassing longitude 14-65?? compared to the same high brightness class for the hemisphere encompassing 122-156?? longitude. We conclude that an albedo dichotomy observed in continental sized units on Titan is due not only to one unit having more areal coverage of reflective material than the other but the material on the brighter unit is intrinsically more reflective than the most reflective material on the other unit. This suggests that surface renewal processes are more widespread on Titan's more reflective units than on its less reflective units. We note that one of our photometric control points has increased in reflectance by 12% relative to the surrounding terrain from July of 2004 to April and May of 2005. Possible causes of this effect include atmospheric processes such as ground fog or orographic clouds; the suggestion of active volcanism cannot be ruled out. Several interesting circular features which resembled impact craters were identified on Titan's surface at the time of the initial Titan flyby in July of 2004. We traced photometric profiles through two of these candidate craters and attempted to fit these profiles to the photometric properties expected from model depressions. We find that the best-fit attempt to model these features as craters requires that they be unrealistically deep, approximately 70 km deep. We conclude that despite their appearance, these circular features are not craters, however, the possibility that they are palimpsests cannot be ruled out. We used two methods to test for the presence of vast expanses of liquids on Titan's surface that had been suggested to resemble oceans. Specular reflection of sunlight would be indicative of widespread liquids on the surface; we found no evidence of this. A large liquid body should also show uniformity in photometric profile; we found the profiles to be highly variable. The lack of specular reflection and the high photometric variability in the profiles across candidate oceans is inconsistent with the presence of vast expanses of flat-lying liquids on Titan's surface. While liquid accumulation may be present as small, sub-pixel-sized bodies, or in areas of the surface which still remain to be observed by VIMS, the presence of large ocean-sized accumulations of liquids can be ruled out. The Cassini orbital tour offers the opportunity for VIMS to image the same parts of Titan's surface repeatedly at many different illumination and observation geometries. This creates the possibility of understanding the properties of Titan's atmosphere and haze by iteratively adapting models to create a best fit to the surface reflectance properties. ?? 2006 Elsevier Ltd. All rights reserved.

Nelson, R.M.; Brown, R.H.; Hapke, B.W.; Smythe, W.D.; Kamp, L.; Boryta, M.D.; Leader, F.; Baines, K.H.; Bellucci, G.; Bibring, J.-P.; Buratti, B.J.; Capaccioni, F.; Cerroni, P.; Clark, R.N.; Combes, M.; Coradini, A.; Cruikshank, D.P.; Drossart, P.; Formisano, V.; Jaumann, R.; Langevin, Y.; Matson, D.L.; McCord, T.B.; Mennella, V.; Nicholson, P.D.; Sicardy, B.; Sotin, C.

2006-01-01

122

Late Amazonian Glaciation at the Dichotomy Boundary on Mars: New Evidence from MRO for Glacial Thickness Maxima and Multiple Glacial Phases  

NASA Astrophysics Data System (ADS)

Lineated valley fill (LVF) in fretted valleys at the dichotomy boundary has been interpreted as glacial in origin. Unknown are 1) the original thickness of the glacier ice, 2) the amount of ice-surface lowering, through sublimation, retreat and ice loss, to its presently observed level, and 3) whether there were multiple periods of glaciation. We address these questions through analysis of an integrated LVF glacial landsystem along the dichotomy boundary at the contact of Protonilus Mensae and Coloe Fossae (41°N, 54.5°E). Analysis of MRO CTX and HiRISE data confirm the presence of a 5-km wide loop-like lobe emanating from LVF that terminates in an elevated box canyon, and the remnant flow patterns do not correlate with present-day topography, indicating that a substantially increased volume of ice was necessary to alter the flow regime and deposit the observed features. Additionally, the upper limit of glacial deposits at this site is topographically consistent with other regional glacial deposits in Coloe Fossae and Protonilus Mensae. The elevation difference between the upper limit of glacial deposits and the current surface of the LVF at the study site is ~920 meters. We interpret this difference to reflect the minimum amount of ice-surface lowering of the valley glacier system during retreat. Consistent with a general lowering of the ice surface are multiple moraines and/or trimlines, and changes in LVF flow patterns, including local flow reversals, as the ice retreated and decreased in thickness. The clear superposition of several lobes out onto the current surface of the LVF indicates that a less extensive phase of glaciation followed the lowering of the valley glacial landsystem. These data suggest that the major Late Amazonian glaciation that produced LVF in this region involved significantly larger amounts of glacier ice than previously thought, and that subsequent, less extensive local tributary glaciation followed.

Dickson, J. L.; Head, J. W.; Marchant, D. R.

2007-12-01

123

Toward a Multidimensional Continuum Model of Functional Psychoses for Research Purposes  

Microsoft Academic Search

\\u000a Schizophrenia (SZ), schizoaffective disorder (SA), major depressive disorder (MDD) and bipolar disorder (BPD) are clinically\\u000a heterogeneous conditions called “functional psychoses” (FP). The paradigm, underlying the current model of FP, was based on\\u000a Kraepelinian dichotomy and was a practical starting point for the categorical classification of FP. Nevertheless, the concept\\u000a is increasingly challenged by emerging data from modern research in the

Michael S. Ritsner

124

A Revelation: Quantum-Statistics and Classical-Statistics are Analytic-Geometry Conic-Sections and Numbers\\/Functions: Euler, Riemann, Bernoulli Generating-Functions: Conics to Numbers\\/Functions Deep Subtle Connections  

Microsoft Academic Search

Quantum-statistics Dichotomy: Fermi-Dirac(FDQS) Versus Bose-Einstein(BEQS), respectively with contact-repulsion\\/non-condensation(FDCR) versus attraction\\/ condensationBEC are manifestly-demonstrated by Taylor-expansion ONLY of their denominator exponential, identified BOTH as Descartes analytic-geometry conic-sections, FDQS as Elllipse (homotopy to rectangle FDQS distribution-function), VIA Maxwell-Boltzmann classical-statistics(MBCS ) to Parabola MORPHISM, VS. BEQS to Hyperbola, Archimedes' HYPERBOLICITY INEVITABILITY, and as well generating-functions[Abramowitz-Stegun, Handbook Math.-Functions--p. 804!!!], respectively of Euler-numbers\\/functions, (via Riemann

R. Descartes; G.-C. Rota; L. Euler; J. D. Bernoulli; Edward Carl-Ludwig Siegel

2011-01-01

125

Density-dependent quiescence in glioma invasion: instability in a simple reaction–diffusion model for the migration/proliferation dichotomy  

PubMed Central

Gliomas are very aggressive brain tumours, in which tumour cells gain the ability to penetrate the surrounding normal tissue. The invasion mechanisms of this type of tumour remain to be elucidated. Our work is motivated by the migration/proliferation dichotomy (go-or-grow) hypothesis, i.e. the antagonistic migratory and proliferating cellular behaviours in a cell population, which may play a central role in these tumours. In this paper, we formulate a simple go-or-grow model to investigate the dynamics of a population of glioma cells for which the switch from a migratory to a proliferating phenotype (and vice versa) depends on the local cell density. The model consists of two reaction–diffusion equations describing cell migration, proliferation and a phenotypic switch. We use a combination of numerical and analytical techniques to characterize the development of spatio-temporal instabilities and travelling wave solutions generated by our model. We demonstrate that the density-dependent go-or-grow mechanism can produce complex dynamics similar to those associated with tumour heterogeneity and invasion. PMID:22873675

Pham, Kara; Chauviere, Arnaud; Hatzikirou, Haralambos; Li, Xiangrong; Byrne, Helen M.; Cristini, Vittorio; Lowengrub, John

2013-01-01

126

A potential role of reward and punishment in the facilitation of the emotion-cognition dichotomy in the Iowa Gambling Task  

PubMed Central

The Iowa Gambling Task (IGT) is based on the assumption that a decision maker is equally motivated to seek reward and avoid punishment, and that decision making is governed solely by the intertemporal attribute (i.e., preference for an option that produces an immediate outcome instead of one that yields a delayed outcome is believed to reflect risky decision making and is considered a deficit). It was assumed in the present study that the emotion- and cognition-based processing dichotomy manifests in the IGT as reward and punishment frequency and the intertemporal attribute. It was further proposed that the delineation of emotion- and cognition-based processing is contingent upon reward and punishment as manifested in the frame of the task (variant type) and task motivation (instruction type). The effects of IGT variant type (reward vs. punishment) and instruction type (task motivation induced by instruction types: reward, punishment, reward and punishment, or no hint) on the intertemporal and frequency attributes of IGT decision-making were analyzed. Decision making in the reward variant was equally governed by both attributes, and significantly affected by instruction type, while decision making in the punishment variant was differentially affected by the two attributes and not significantly impacted by instruction type. These results suggest that reward and punishment manifested via task frame as well as the task motivation may facilitate the differentiation of emotion- and cognition-based processing in the IGT. PMID:24381567

Singh, Varsha

2013-01-01

127

Suppression of Smad-1 mRNA expression level by Smad-2 likely control dichotomy of NF-?B and Smads mediated activation.  

PubMed

The aim of this study was to find out how NF-?B and Smad-mediated signaling influenced the expression of astrogliogenic versus neurogenic markers of brain development in U4C cells which were either enriched (Tg Jak-1) or deprived in Jak-1 molecule (Jak-1 KO). Genetically modified U4C cells were transfected with NF-kB reporter plasmid in order to follow its activation when cells were cotransfected with different combinations of Smads constructs. In wild type cells no significant activation of NF-?B was observed while genetically modified cells exhibited somewhat different pattern of NF-?B activation depending on the Smad constructs combination used. The absence of NF-?B activation in Jak-1 transgenic cells transfected with Smad-1 plus Smad-3 was accompanied by the appearance of apoptotic cells as revealed by DAPI staining. Smad-1 expression was undetectable in Jak-1 transgenic cells and was downregulated in wild type cells upon transfection with Smad-2. The absence of p65 nuclear translocation in Smad-2 transfected cells and the presence of Smad-4 in nucleus of the same cells indicates dichotomy in NF-?B and Smads mediated signaling pathways. The significance of this study is that helps to elucidate the point of collaboration among three different signaling pathways - Jak-1 mediated cytokine signaling, NF-?B and Smads mediated pathways. PMID:25261891

Slade, N; Zori?, A; Horvat, B; Vukši?, M; Kostovi?, I; Poljak, L

2015-01-01

128

Dichotomy of hot electron relaxation and delocalized polarons for optimal energy transfer in a model organic donor-acceptor interface  

E-print Network

Charge separation at donor-acceptor interfaces is a complex process that can be strongly limited by the combined action of phonon-induced relaxation and Coulomb potential binding for an electron/hole pair. We propose a fully quantum microscopic approach to this problem, and show that molecular vibrations modulate the trapping probability in a non-monotonous fashion as a function of injection energy, due to polaron formation. This mechanism should control sensitively the efficiency of energy transfer in photovoltaic organic molecules, and bridge the gap between several current conflicting theories.

Bera, Soumya; Fratini, Simone; Ciuchi, Sergio; Florens, Serge

2014-01-01

129

Hot versus Cold: the Dichotomy in Spherical Accretion of Cooling Flows onto Supermassive Black Holes in Elliptical Galaxies, Galaxy Groups, and Clusters  

NASA Astrophysics Data System (ADS)

Feedback heating from active galactic nuclei (AGNs) has been commonly invoked to suppress cooling flows predicted in hot gas in elliptical galaxies, galaxy groups, and clusters. Previous studies have focused on if and how AGN feedback heats the gas but have little paid attention to its triggering mechanism. Using spherically symmetric simulations, we investigate how large-scale cooling flows are accreted by central supermassive black holes (SMBHs) in eight well-observed systems and find an interesting dichotomy. In massive clusters, the gas develops a central cooling catastrophe within about the cooling time (typically ~100-300 Myr), resulting in cold-mode accretion onto SMBHs. However, in our four simulated systems on group and galaxy scales at a low metallicity Z = 0.3 Z ?, the gas quickly settles into a long-term state that has a cuspy central temperature profile extending to several tens to about 100 pc. At the more realistic solar metallicity, two groups (with R e ~ 4 kpc) still host the long-term, hot-mode accretion. Both accretion modes naturally appear in our idealized calculations where only cooling, gas inflow, and compressional heating are considered. The long-term, hot-mode accretion is maintained by the quickly established closeness between the timescales of these processes, preferably in systems with low gas densities, low gas metallicities, and importantly, compact central galaxies, which result in strong gravitational acceleration and compressional heating at the intermediate radii. Our calculations predict that central cuspy temperature profiles appear more often in smaller systems than galaxy clusters, which instead often host significant cold gas and star formation.

Guo, Fulai; Mathews, William G.

2014-01-01

130

A Genetic Dichotomy between Pure Sclerosing Epithelioid Fibrosarcoma (SEF) and Hybrid SEF/Low Grade Fibromyxoid Sarcoma: A Pathologic and Molecular Study of 18 cases  

PubMed Central

Sclerosing epithelioid fibrosarcoma (SEF) is a rare soft tissue tumor exhibiting considerable morphologic overlap with low grade fibromyxoid sarcoma (LGFMS). Moreover, both SEF and LGFMS show MUC4 expression by immunohistochemistry. While the majority of LGFMS cases are characterized by a FUS-CREB3L1 fusion, both FUS-CREB3L2 and EWSR1-CREB3L1 fusions were recently demonstrated in a small number of LGFMS and SEF/LGFMS hybrid tumors. In contrast, recent studies pointed out that SEF harbor frequent EWSR1 rearrangements, with only a minority of cases showing FUS-CREB3L2 fusions. In an effort to further characterize the molecular characteristics of pure SEF and hybrid SEF/LGFMS lesions, we undertook a clinicopathologic, immunohistochemical and genetic analysis of a series of 10 SEF and 8 hybrid SEF/LGFMS tumors. The mortality rate was similar between the two groups, 44% within the pure SEF group and 37% in the hybrid SEF/LGFMS with a mean overall follow-up of 66 months. All but one pure SEF and all hybrid SEF/LGFMS tested cases showed MUC4 immunoreactivity. The majority (90%) of pure SEF cases showed EWSR1 gene rearrangements by FISH with only one case exhibiting FUS rearrangement. Of the 9 EWSR1 positive cases, 6 cases harbored CREB3L1 break-apart, two had CREB3L2 rearrangement (a previously unreported finding) and one lacked evidence of CREB3L1/2 abnormalities. In contrast, all hybrid SEF/LGFMS tumors exhibited FUS and CREB3L2 rearrangements. These results further demarcate a relative cytogenetic dichotomy between pure SEF, often characterized by EWSR1 rearrangements, and hybrid SEF/LGFMS, harboring FUS-CREB3L2 fusion; the latter group recapitulating the genotype of LGFMS. PMID:25231134

Prieto-Granada, Carlos; Zhang, Lei; Chen, Hsiao-Wei; Sung, Yun-Shao; Agaram, Narasimhan P; Jungbluth, Achim; Antonescu, Cristina R

2014-01-01

131

Dichotomy in perceptual learning of interval timing: calibration of mean accuracy and precision differ in specificity and time course.  

PubMed

Our brain is inexorably confronted with a dynamic environment in which it has to fine-tune spatiotemporal representations of incoming sensory stimuli and commit to a decision accordingly. Among those representations needing constant calibration is interval timing, which plays a pivotal role in various cognitive and motor tasks. To investigate how perceived time interval is adjusted by experience, we conducted a human psychophysical experiment using an implicit interval-timing task in which observers responded to an invisible bar drifting at a constant speed. We tracked daily changes in distributions of response times for a range of physical time intervals over multiple days of training with two major types of timing performance, mean accuracy and precision. We found a decoupled dynamics of mean accuracy and precision in terms of their time course and specificity of perceptual learning. Mean accuracy showed feedback-driven instantaneous calibration evidenced by a partial transfer around the time interval trained with feedback, while timing precision exhibited a long-term slow improvement with no evident specificity. We found that a Bayesian observer model, in which a subjective time interval is determined jointly by a prior and likelihood function for timing, captures the dissociative temporal dynamics of the two types of timing measures simultaneously. Finally, the model suggested that the width of the prior, not the likelihoods, gradually shrinks over sessions, substantiating the important role of prior knowledge in perceptual learning of interval timing. PMID:23076112

Sohn, Hansem; Lee, Sang-Hun

2013-01-01

132

THE ROLE OF CORE MASS IN CONTROLLING EVAPORATION: THE KEPLER RADIUS DISTRIBUTION AND THE KEPLER-36 DENSITY DICHOTOMY  

SciTech Connect

We use models of coupled thermal evolution and photo-evaporative mass loss to understand the formation and evolution of the Kepler-36 system. We show that the large contrast in mean planetary density observed by Carter et al. can be explained as a natural consequence of photo-evaporation from planets that formed with similar initial compositions. However, rather than being due to differences in XUV irradiation between the planets, we find that this contrast is due to the difference in the masses of the planets' rock/iron cores and the impact that this has on mass-loss evolution. We explore in detail how our coupled models depend on irradiation, mass, age, composition, and the efficiency of mass loss. Based on fits to large numbers of coupled evolution and mass-loss runs, we provide analytic fits to understand threshold XUV fluxes for significant atmospheric loss, as a function of core mass and mass-loss efficiency. Finally we discuss these results in the context of recent studies of the radius distribution of Kepler candidates. Using our parameter study, we make testable predictions for the frequency of sub-Neptune-sized planets. We show that 1.8-4.0 R{sub ?} planets should become significantly less common on orbits within 10 days and discuss the possibility of a narrow 'occurrence valley' in the radius-flux distribution. Moreover, we describe how photo-evaporation provides a natural explanation for the recent observations of Ciardi et al. that inner planets are preferentially smaller within the systems.

Lopez, Eric D.; Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

2013-10-10

133

Jargonial-Obfuscation(J-O) DISambiguation Elimination via Siegel-Baez Cognition Category-Semantics(C-S) in Siegel FUZZYICS=CATEGORYICS (Son of TRIZ)/(F=C) Tabular List-Format Dichotomy Truth-Table Matrix Analytics  

NASA Astrophysics Data System (ADS)

NOT "philosophy" per se but raising serious salient Arnol'd [Huygens and Barrow, Newton and Hooke(96)] questions begged is Rota empiricism Husserl VS. Frege maths-objects Dichotomy controversy: Hill-Haddock[Husserl or Frege?(00)]as manifestly-demonstrated by Hintikka[B.U.]-Critchey[Derrida Deconstruction Ethics(78)] deconstruction; Altshuler TRIZ; Siegel F=C/C-S; Siegel-Baez(UCR) Cognition C-S = "Category-theory "+" Cognitive-Semantics[Wierzbica-Langacker-Lakoff-Nunez[Where Maths Comes From(00)]-Fauconnier-Turner[Blending(98)]-Coulson[Semantic-Leaps (00)

Siegel, Carl Ludwig; Carl-Ludwig Siegel, Edward

2011-03-01

134

Function and quality of life in patients with recurvatum deformity after primary total knee arthroplasty: a review of our joint registry.  

PubMed

The aim of this paper is to assess function and quality of life in patients with recurvatum at 2 years after primary total knee arthroplasty. This prospective study involves 2587 total knee arthroplasty from 2004 to 2008 with 2-year follow-up. Patients' demographics, diagnosis, implants, range of motion, laxity, and knee and SF-36 scores were recorded. Recurvatum deformity of 0°, 1° to 5°, 6° to 10°, and more than 10° were classified as grades 0, 1, 2, and 3, respectively. Grade 1 had similar functional scores to grade 0 but significantly better SF1, SF4, SF5, and SF8 when compared with grades 2 and 3. Patients with mediolateral translation of more than 5 mm were more likely to have grades 2 and 3 recurvatum (P = .01), indicating global laxity. Postoperative recurvatum of more than 5° significantly impacts function and quality of life of patients. PMID:22153947

Siddiqui, Mohd Mashfiqul A; Yeo, Seng Jin; Sivaiah, Potla; Chia, Shi-Lu; Chin, Pak Lin; Lo, Ngai Nung

2012-06-01

135

The Land Use and Land Cover Dichotomy: A Comparison of Two Land Classification Systems in Support of Urban Earth Science Applications  

NASA Technical Reports Server (NTRS)

One is likely to read the terms 'land use' and 'land cover' in the same sentence, yet these concepts have different origins and different applications. Land cover is typically analyzed by earth scientists working with remotely sensed images. Land use is typically studied by urban planners who must prescribe solutions that could prevent future problems. This apparent dichotomy has led to different classification systems for land-based data. The works of earth scientists and urban planning practitioners are beginning to come together in the field of spatial analysis and in their common use of new spatial analysis technology. In this context, the technology can stimulate a common 'language' that allows a broader sharing of ideas. The increasing amount of land use and land cover change challenges the various efforts to classify in ways that are efficient, effective, and agreeable to all groups of users. If land cover and land uses can be identified by remote methods using aerial photography and satellites, then these ways are more efficient than field surveys of the same area. New technology, such as high-resolution satellite sensors, and new methods, such as more refined algorithms for image interpretation, are providing refined data to better identify the actual cover and apparent use of land, thus effectiveness is improved. However, the closer together and the more vertical the land uses are, the more difficult the task of identification is, and the greater is the need to supplement remotely sensed data with field study (in situ). Thus, a number of land classification methods were developed in order to organize the greatly expanding volume of data on land characteristics in ways useful to different groups. This paper distinguishes two land based classification systems, one developed primarily for remotely sensed data, and the other, a more comprehensive system requiring in situ collection methods. The intent is to look at how the two systems developed and how they can work together so that land based information can be shared among different users and compared over time.

McAllister, William K.

2003-01-01

136

Water balance and renal function in two species of African lungfish Protopterus dolloi and Protopterus annectens.  

PubMed

The basic physiology of water balance and kidney function was characterized in two species of African lungfish, Protopterus dolloi and Protopterus annectens. Diffusive water efflux rate constants were low (0.13 h(-1)-0.38 h(-1) in various series) relative to values in freshwater teleost fish. Efflux rate constants increased approximately 3-fold after feeding in both species, and were greatly decreased after 8 months terrestrialization (P. dolloi only tested). Urine flow rates (UFR, 3.9-5.2 mL kg(-1) h(-1)) and glomerular filtration rates (GFR, 6.6-9.3 mL kg(-1) h(-1)) were quite high relative to values in most freshwater teleosts. However urinary ion excretion rates were low, with net re-absorption of >99% Na(+), >98% Cl(-), and >78% Ca(2+) from the primary filtrate, comparable to teleosts. Net water re-absorption was significantly greater in P. dolloi (56%) than in P. annectens (23%). We conclude that renal function in lungfish is similar to that in other primitive freshwater fish, but there is an interesting dichotomy between diffusive and osmotic permeabilities. Aquatic lungfish have low diffusive water permeability, an important pre-adaptation to life on land, and in accord with greatly reduced gill areas and low metabolic rates. However osmotic permeability is high, 4-12 times greater than diffusive permeability. A role for aquaporins in this dichotomy is speculated. PMID:18835584

Patel, Monika; Iftikar, Fathima I; Smith, Richard W; Ip, Yuen K; Wood, Chris M

2009-02-01

137

Gauge-Invariant Energy Functional in Relativistic Schroedinger Theory  

E-print Network

The non-invariant energy functional of the preceding paper is improved in order to obtain its gauge-invariant form by strictly taking into account the non-Abelian character of Relativistic Schroedinger Theory (RST). As an application of the results, the dichotomy of positronium with respect to singlet and triplet states is discussed (ortho- and para-positronium). The degeneracy of the ortho- and para-states occurs in RST if (i) the magnetic interactions are neglected (as in the conventional theory) and (ii) the anisotropy of the electric interaction potential is disregarded. In view of such a very crude approximation procedure, the non-relativistic positronium spectrum in RST agrees amazingly well with the conventional predictions.

M. Mattes; M. Sorg

2009-08-29

138

Physics Proofs of Four Millennium-Problems(MP) via CATEGORY-SEMANTICS(C-S)/F=C Aristotle SQUARE-of-OPPOSITION(SoO) DEduction-LOGIC DichotomY  

NASA Astrophysics Data System (ADS)

Siegel-Baez C-S/F=C tabular list-format matrix truth-table analytics SoO jargonial-obfuscation elimination query WHAT? yields four ``pure''-maths MP ``Feet of Clay!!!'' proofs:(1)Siegel [AMS Natl.Mtg.(2002)-Abs.#:973-03-126:(@CCNY;1964!!!)<<<(1994; Wiles)]Fermat's: Last-Theorem = Least-Action Principle; (2) P=/=NP TRIVIAL simple Euclid geometry/dimensions: NO computer anything;``Feet of Clay!!!''; (3)Birch-Swinnerton-Dyer conjecture; (4)Riemann-hypotheses via combination of: Siegel [AMS Natl.Mtg. (2002)-Abs.#:973-60-124 digits logarithmic-law simple algebraic- inversion to ONLY BEQS with ONLY zero-digit BEC, AND Rayleigh [(1870);graph-theory ``short-CUT method''[Doyle- Snell,Random- Walks & Electric-Networks,MAA(1981)]-``Anderson'' [PRL(1958)] critical-strip 1/2 complex-plane localization!!! SoO DichotomY (``v'') IdentitY: numbers(Euler v Bernoulli) = (Sets v Multisets) = Quantum-Statistics(F.-D. v B.-E.) = Power- Spectra(1/f^(0) v 1/f^(1.000...) = Conic-Sections(Ellipse v (Parabola) v Hyperbola) = Extent(Locality v Globality); Siegel [MRS Fractals Symp.(1989)](so MIScalled)``complexity'' as UTTER- SIMPLICITY (!!!) v COMPLICATEDNESS MEASURE(S) definition.

Clay, L.; Siegel, E.

2010-03-01

139

Physics Proofs of Four Millennium-Problems(MP) via CATEGORY-SEMANTICS(C-S)/F=C Aristotle SQUARE-of-OPPOSITION(SoO) DEduction-LOGIC DichotomY  

NASA Astrophysics Data System (ADS)

Siegel-Baez Cognitive-Category-Semantics"(C-C-S) tabular list-format matrix truth-table analytics SoO jargonial-obfuscation elimination query WHAT? yields four "pure"-maths MP "Feet of Clay!!!" proofs: (1) Siegel [AMS Natl.Mtg.(02)-Abs.973-03-126: (CCNY;64)!!!<<<(94;Wiles)] Fermat's: Last-Thm. = Least-Action Ppl.; (2) P=/=NP TRIVIAL simple Euclid geometry/dimensions: NO computer anything"Feet of Clay!!!"; (3) Birch-Swinnerton-Dyer conjecture; (4) Riemann-hypotheses via COMBO.: Siegel[AMS Natl.Mtg.(02)-Abs.973-60-124] digits log-law inversion to ONLY BEQS with ONLY zero-digit BEC, AND Rayleigh[1870;graph-thy."short-CUT method"[Doyle-Snell, Random-Walks & Electric-Nets,MAA(81)]-"Anderson"[(58)] critical-strip C-localization!!! SoO DichotomY ("V") IdentitY: #s:( Euler v Bernoulli) = (Sets v Multisets) = Quantum-Statistics(FD v BE) = Power-Spectra(1/f?(0) v 1/f?(1)) = Conic-Sections(Ellipse v Hyperbola) = Extent(Locality v Globality);Siegel[(89)] (so MIScalled) "complexity" as UTTER-SIMPLICITY(!!!) v COMPLICATEDNESS MEASURE(S) definition.

Clay, London; Carl-Ludwig Siegel, Edward

2011-03-01

140

Mediolateral hoof balance in relation to the handedness of apprentice farriers  

Microsoft Academic Search

Horses that had been trimmed and shod by apprentice farriers were sourced from the Royal School of Military Engineering, Melton Mowbray (37 horses) and from the Household Cavalry, Knightsbridge (54 horses). The lateral and medial hoof wall angles of both forelimbs were measured using a Ruidoso hoof gauge by the same operator. The difference between the lateral and medial hoof

A. Ronchetti; P. Day; R. Weller

2011-01-01

141

Amplitude effects of medio-lateral mechanical and visual perturbations on gait.  

PubMed

Falls during walking are a major contributor to accidental deaths and injuries that can result in debilitating hospitalization costs, lost productivity, and diminished quality of life. To reduce these losses, we must develop a more profound understanding of the characteristic responses to perturbations similar to those encountered in daily life. This study addresses this issue by building on our earlier studies that examined mechanical and visual perturbations in the same environment by applying the same continuous pseudo-random perturbations at multiple (3 mechanical, 5 visual) amplitudes. Walking variability during mechanical perturbations increased significantly with amplitude for all subjects and differences as measured by variabilities of step width, COM position, and COM velocity. These parameters were the only ones sensitive to the presence of visual perturbations, but none of them changed significantly with perturbation amplitude. Additionally, visual perturbation effects were far less consistent across participants, with several who were essentially unaffected by visual perturbations at any level. The homogeneity of the mechanical perturbation effects demonstrates that human responses to mechanical perturbations are similar because they are driven by kinetics that require similar corrections that must be made in order to maintain balance. Conversely, responses to visual perturbations are driven by the perceived need to make corrections and this perception is not accurate enough to produce amplitude-related corrections, even for a single participant, nor is this perception consistent across individuals. This latter finding is likely to be relevant to future visual perturbation studies and the diagnosis and rehabilitation of gait and balance disorders. PMID:22648147

Terry, Kevin; Sinitski, Emily H; Dingwell, Jonathan B; Wilken, Jason M

2012-07-26

142

Contributions of muscles to mediolateral ground reaction force over a range of walking speeds  

E-print Network

of fall-related fractures was estimated to exceed $19 billion in the year 2000 in the United States to another during double support. & 2012 Elsevier Ltd. All rights reserved. 1. Introduction Impaired control (Stevens et al., 2006). One-year mortality rates for hip fractures range from 12% to 20% for women and 21

Delp, Scott

143

Relationship between static postural control and the level of functional abilities in children with cerebral palsy  

PubMed Central

Background: Postural control deficits can impair functional performance in children with cerebral palsy (CP) in daily living activities. Objective: To verify the relationship between standing static postural control and the functional ability level in children with CP. Method: The postural control of 10 children with CP (gross motor function levels I and II) was evaluated during static standing on a force platform for 30 seconds. The analyzed variables were the anteroposterior (AP) and mediolateral (ML) displacement of the center of pressure (CoP) and the area and velocity of the CoP oscillation. The functional abilities were evaluated using the mean Pediatric Evaluation of Disability Inventory (PEDI) scores, which evaluated self-care, mobility and social function in the domains of functional abilities and caregiver assistance. Results: Spearman's correlation test found a relationship between postural control and functional abilities. The results showed a strong negative correlation between the variables of ML displacement of CoP, the area and velocity of the CoP oscillation and the PEDI scores in the self-care and caregiver assistance domains. Additionally, a moderate negative correlation was found between the area of the CoP oscillation and the mobility scores in the caregiver assistance domain. We used a significance level of 5% (p <0.05). Conclusions: We observed that children with cerebral palsy with high CoP oscillation values had lower caregiver assistance scores for activities of daily living (ADL) and consequently higher levels of caregiver dependence. These results demonstrate the repercussions of impairments to the body structure and function in terms of the activity levels of children with CP such that postural control impairments in these children lead to higher requirements for caregiver assistance. PMID:25054383

Pavão, Sílvia L.; Nunes, Gabriela S.; Santos, Adriana N.; Rocha, Nelci A. C. F.

2014-01-01

144

Twelve weeks of BodyBalance® training improved balance and functional task performance in middle-aged and older adults  

PubMed Central

Purpose The purpose of the study was to evaluate the effect of BodyBalance® training on balance, functional task performance, fear of falling, and health-related quality of life in adults aged over 55 years. Participants and methods A total of 28 healthy, active adults aged 66±5 years completed the randomized controlled trial. Balance, functional task performance, fear of falling, and self-reported quality of life were assessed at baseline and after 12 weeks. Participants either undertook two sessions of BodyBalance per week for 12 weeks (n=15) or continued with their normal activities (n=13). Results Significant group-by-time interactions were found for the timed up and go (P=0.038), 30-second chair stand (P=0.037), and mediolateral center-of-pressure range in narrow stance with eyes closed (P=0.017). There were no significant effects on fear of falling or self-reported quality of life. Conclusion Twelve weeks of BodyBalance training is effective at improving certain balance and functional based tasks in healthy older adults. PMID:25395844

Nicholson, Vaughan P; McKean, Mark R; Burkett, Brendan J

2014-01-01

145

Cellular Dichotomy Between Anchorage-Independent Growth Responses to bFGF and TA Reflects Molecular Switch in Commitment to Carcinogenesis  

SciTech Connect

We have investigated gene expression patterns underlying reversible and irreversible anchorage-independent growth (AIG) phenotypes to identify more sensitive markers of cell transformation for studies directed at interrogating carcinogenesis responses. In JB6 mouse epidermal cells, basic fibroblast growth factor (bFGF) induces an unusually efficient and reversible AIG response, relative to 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced AIG which is irreversible. The reversible and irreversible AIG phenotypes are characterized by largely non-overlapping global gene expression profiles. However, a subset of differentially expressed genes were identified as common to reversible and irreversible AIG phenotypes, including genes regulated in a reciprocal fashion. Hepatic leukemia factor (HLF) and D-site albumin promoter-binding protein (DBP) were increased in both bFGF and TPA soft agar colonies and selected for functional validation. Ectopic expression of human HLF and DBP in JB6 cells resulted in a marked increase in TPA- and bFGF-regulated AIG responses. HLF and DBP expression were increased in soft agar colonies arising from JB6 cells exposed to gamma radiation and in a human basal cell carcinoma tumor tissue, relative to paired non-tumor tissue. Subsequent biological network analysis suggests that many of the differentially expressed genes that are common to bFGF- and TPA-dependent AIG are regulated by c-Myc, SP-1 and HNF-4 transcription factors. Collectively, we have identified a potential molecular switch that mediates the transition from reversible to irreversible AIG.

Waters, Katrina M.; Tan, Ruimin; Opresko, Lee K.; Quesenberry, Ryan D.; Bandyopadhyay, Somnath; Chrisler, William B.; Weber, Thomas J.

2009-11-01

146

Morphology and behaviour: functional links in development and evolution  

PubMed Central

Development and evolution of animal behaviour and morphology are frequently addressed independently, as reflected in the dichotomy of disciplines dedicated to their study distinguishing object of study (morphology versus behaviour) and perspective (ultimate versus proximate). Although traits are known to develop and evolve semi-independently, they are matched together in development and evolution to produce a unique functional phenotype. Here I highlight similarities shared by both traits, such as the decisive role played by the environment for their ontogeny. Considering the widespread developmental and functional entanglement between both traits, many cases of adaptive evolution are better understood when proximate and ultimate explanations are integrated. A field integrating these perspectives is evolutionary developmental biology (evo-devo), which studies the developmental basis of phenotypic diversity. Ultimate aspects in evo-devo studies—which have mostly focused on morphological traits—could become more apparent when behaviour, ‘the integrator of form and function’, is integrated into the same framework of analysis. Integrating a trait such as behaviour at a different level in the biological hierarchy will help to better understand not only how behavioural diversity is produced, but also how levels are connected to produce functional phenotypes and how these evolve. A possible framework to accommodate and compare form and function at different levels of the biological hierarchy is outlined. At the end, some methodological issues are discussed. PMID:21690124

Bertossa, Rinaldo C.

2011-01-01

147

Vascular smooth muscle phenotypic diversity and function  

PubMed Central

The control of force production in vascular smooth muscle is critical to the normal regulation of blood flow and pressure, and altered regulation is common to diseases such as hypertension, heart failure, and ischemia. A great deal has been learned about imbalances in vasoconstrictor and vasodilator signals, e.g., angiotensin, endothelin, norepinephrine, and nitric oxide, that regulate vascular tone in normal and disease contexts. In contrast there has been limited study of how the phenotypic state of the vascular smooth muscle cell may influence the contractile response to these signaling pathways dependent upon the developmental, tissue-specific (vascular bed) or disease context. Smooth, skeletal, and cardiac muscle lineages are traditionally classified into fast or slow sublineages based on rates of contraction and relaxation, recognizing that this simple dichotomy vastly underrepresents muscle phenotypic diversity. A great deal has been learned about developmental specification of the striated muscle sublineages and their phenotypic interconversions in the mature animal under the control of mechanical load, neural input, and hormones. In contrast there has been relatively limited study of smooth muscle contractile phenotypic diversity. This is surprising given the number of diseases in which smooth muscle contractile dysfunction plays a key role. This review focuses on smooth muscle contractile phenotypic diversity in the vascular system, how it is generated, and how it may determine vascular function in developmental and disease contexts. PMID:20736412

2010-01-01

148

Hypergeometric Functions  

NSDL National Science Digital Library

This page includes the encyclopedia entries for hypergeometric functions including Hermit, parabolic cylinder and Laguerre functions, Chebyshev and Fibonacci functions, Legendre functions, Gegenbauer and Jacobi functions, confluent hypergeometric functions, hypergeometric functions, Meijer G functions, hypergeometric functions of several variables and angular momentum functions.

149

Molecular insights into NF2/Merlin tumor suppressor function.  

PubMed

The FERM domain protein Merlin, encoded by the NF2 tumor suppressor gene, regulates cell proliferation in response to adhesive signaling. The growth inhibitory function of Merlin is induced by intercellular adhesion and inactivated by joint integrin/receptor tyrosine kinase signaling. Merlin contributes to the formation of cell junctions in polarized tissues, activates anti-mitogenic signaling at tight-junctions, and inhibits oncogenic gene expression. Thus, inactivation of Merlin causes uncontrolled mitogenic signaling and tumorigenesis. Merlin's predominant tumor suppressive functions are attributable to its control of oncogenic gene expression through regulation of Hippo signaling. Notably, Merlin translocates to the nucleus where it directly inhibits the CRL4(DCAF1) E3 ubiquitin ligase, thereby suppressing inhibition of the Lats kinases. A dichotomy in NF2 function has emerged whereby Merlin acts at the cell cortex to organize cell junctions and propagate anti-mitogenic signaling, whereas it inhibits oncogenic gene expression through the inhibition of CRL4(DCAF1) and activation of Hippo signaling. The biochemical events underlying Merlin's normal function and tumor suppressive activity will be discussed in this Review, with emphasis on recent discoveries that have greatly influenced our understanding of Merlin biology. PMID:24726726

Cooper, Jonathan; Giancotti, Filippo G

2014-08-19

150

Chimaeric sounds reveal dichotomies in auditory perception  

PubMed Central

By Fourier's theorem1, signals can be decomposed into a sum of sinusoids of different frequencies. This is especially relevant for hearing, because the inner ear performs a form of mechanical Fourier transform by mapping frequencies along the length of the cochlear partition. An alternative signal decomposition, originated by Hilbert2, is to factor a signal into the product of a slowly varying envelope and a rapidly varying fine time structure. Neurons in the auditory brainstem3–6 sensitive to these features have been found in mammalian physiological studies. To investigate the relative perceptual importance of envelope and fine structure, we synthesized stimuli that we call ‘auditory chimaeras’, which have the envelope of one sound and the fine structure of another. Here we show that the envelope is most important for speech reception, and the fine structure is most important for pitch perception and sound localization. When the two features are in conflict, the sound of speech is heard at a location determined by the fine structure, but the words are identified according to the envelope. This finding reveals a possible acoustic basis for the hypothesized ‘what’ and ‘where’ pathways in the auditory cortex7–10. PMID:11882898

Smith, Zachary M.; Delgutte, Bertrand; Oxenham, Andrew J.

2008-01-01

151

Dichotomies in Teaching, Application, and Ethics  

ERIC Educational Resources Information Center

In this article, the authors propose a move from the old control model of teaching, managing, and leading based on stability and power to a new enterprise model based on speed and constant self-innovation. They hope to promote the practice of a rapid incremental innovation strategy that produces practitioners and educators dedicated to continuous…

Heames, Joyce T.; Service, Robert W.

2003-01-01

152

Tutoring and Teaching: Continuum, Dichotomy, or Dialectic?  

ERIC Educational Resources Information Center

A writing center serves freshmen and sophomores at Casper Community College in Casper, Wyoming and upper level classes at University of Wyoming/Casper College. The arrangement raises questions about the effectiveness of peer tutoring. Tutors were labeled "writing assistants" and those who came to the center for help were called "writers" or…

Raines, Helon H.

153

Developers and Deliverers: The Potential Dichotomy.  

ERIC Educational Resources Information Center

Examines the relationship between course developers and instructors in large corporations. Highlights include hiring practices for training department personnel; qualifications sought by the organization; self-report of competencies; separation of responsibilities; job frustrations; role of technology; and management's role in facilitating…

Luoma-Overstreet, Kristine

1993-01-01

154

Elliptic Functions  

NSDL National Science Digital Library

This page includes the encyclopedia entries for elliptic functions including Jacobi theta functions, Siegel theta functions, Neville theta functions, Weierstrass functions and inverses, Weierstrass utility functions, Jacobi functions and inverses, modular functions and inverses, arithmetic geometric mean and elliptic exponential and logarithmic functions.

155

Influence of Resistance Exercise Training to Strengthen Muscles across Multiple Joints of the Lower Limbs on Dynamic Balance Functions of Stroke Patients.  

PubMed

[Purpose] The objective of this study was to evaluate the effects of resistance exercise training for strengthening muscles across multiple joints on the dynamic balance function of stroke patients. [Subjects and Methods] Subjects in the training group (n=14) and the control group (n=14) received conservative physical therapy for 30 minutes per day, five days per week, for a period of six weeks. The training group additionally performed three sets (eight to 10 repetitions per set) of resistance exercise at 70% of the 1-repetition maximum (1RM) to strengthen muscles across multiple joints. The control group did the same exercises for the same duration but without resistance. To assess dynamic balance function, before and after the intervention, we measured antero-posterior (A-P) and medio-lateral (M-L) sway distances, the Berg balance scale (BBS), and the timed up and go (TUG) times. [Results] Compared to pre-intervention values, the BBS score showed significant increases in both groups, and A-P and M-L sway distances and TUG times showed significant decreases in both groups. Changes in A-P and M-L sway distances, BBS scores, and TUG times were significantly different between the muscle training group and the control group. [Conclusion] Training involving muscle strength across multiple joints is an effective intervention for improvement of dynamic balance function of stroke patients. PMID:25202193

Son, Sung Min; Park, Myung Kyu; Lee, Na Kyung

2014-08-01

156

Conceptual structure and social functions of behavior explanations: beyond person--situation attributions.  

PubMed

The traditional approach to studying behavior explanations involves treating them as either person causes or situation causes and assessing them by using rating scales. An analysis of people's free-response behavior explanations reveals, however, that the conceptual distinctions people use in their explanations are more complex and sophisticated than the person-situation dichotomy suggests. The authors, therefore, introduce a model of the conceptual structure of folk behavior explanations (the network of concepts and assumptions on which explanations are based) and test it in 4 studies. The modes and features of behavior explanations within this conceptual structure also have specific social functions. In 2 additional studies, the authors demonstrate that people alter distinct features of their explanations when pursuing particular impression-management goals and that listeners make inferences about explainers' goals on the basis of these features. PMID:10981836

Malle, B F; Knobe, J; O'Laughlin, M J; Pearce, G E; Nelson, S E

2000-09-01

157

Functional magnetic resonance imaging of the rat cerebellum during electrical stimulation of the fore- and hindpaw at 7 T  

NASA Astrophysics Data System (ADS)

Blood oxygenation level dependent contrast (BOLD) functional MRI responses at 7T were observed in the cerebellum of alpha- chloralose anesthetized rats in response to innocuous electrical stimulation of a forepaw or hindpaw. The responses were imaged in both coronal and sagittal slices which allowed for a clear delineation and localization of the observed activations. We demonstrate the validity of our fMRI protocol by imaging the responses in somatosensory cortex to the same stimuli and by showing a high level of reproducibility of the cerebellar responses. Widespread bilateral activations were found with mainly a patchy and medio-lateral band organization, more pronounced ipsilaterally. There was no overlap between the cerebellar activations caused by forepaw or hindpaw stimulation. Most remarkable was the overall horizontal organization of these responses: for both stimulation paradigms the patches and bands of activation were roughly positioned in either a cranial or caudal plane running antero-posteriorly through the whole cerebellum. This is the first fMRI study in the cerebellum of the rat. We relate our findings to the known projection patterns found with other techniques and to human fMRI studies. The horizontal organization found wasn't observed before in other studies using other techniques.

Peeters, Ronald; Verhoye, Marleen; Vos, Bart; De Schutter, Erik; Van der Linden, Anne-Marie

1999-05-01

158

Elementary Functions  

NSDL National Science Digital Library

This page includes the encyclopedia entries for power functions (square root and power), exponential functions, trigonometric functions (e.g. sin, cos), inverse trigonometric functions (e.g. arcSin, arcCos), hyperbolic functions (e.g. sinh, cosh), inverse hyperbolic functions (e.g. arcSinh, arcCosh), product logarightms, roots, maximum and minimum and cardinal functions.

159

Functional Programming Functional Programming  

E-print Network

program + inputs = function + arguments 7/76 #12;example specification L: [*rat] L 8/76 #12;example specification L: [*rat] L L = 9/76 #12;example specification L: [*rat] L L = n: 0,..#L+1 L [n;..#L] 0 10/76 #12;example specification L: [*rat] L L = n: 0,..#L+1 L [n;..#L] 0 n: 0,..#L+1 L [n;..#L] = 11

Hehner, Eric C.R.

160

Steady-state probability density function of the phase error for a DPLL with an integrate-and-dump device  

NASA Technical Reports Server (NTRS)

The steady-state behavior of a particular type of digital phase-locked loop (DPLL) with an integrate-and-dump circuit following the phase detector is characterized in terms of the probability density function (pdf) of the phase error in the loop. Although the loop is entirely digital from an implementation standpoint, it operates at two extremely different sampling rates. In particular, the combination of a phase detector and an integrate-and-dump circuit operates at a very high rate whereas the loop update rate is very slow by comparison. Because of this dichotomy, the loop can be analyzed by hybrid analog/digital (s/z domain) techniques. The loop is modeled in such a general fashion that previous analyses of the Real-Time Combiner (RTC), Subcarrier Demodulator Assembly (SDA), and Symbol Synchronization Assembly (SSA) fall out as special cases.

Simon, M.; Mileant, A.

1986-01-01

161

Brain functional connectivity density and individual fluid reasoning capacity in healthy young adults.  

PubMed

Functional connectivity density (FCD) is a newly developed data-driven method to measure the number of functional connections of each voxel, possibly providing new insight into the neural correlates of fluid reasoning. Here, we recruited 211 healthy young adults (91 men and 120 women) to investigate associations between the global FCD and fluid reasoning capacity as measured by the Raven's Standard Progressive Matrices. Raven's Standard Progressive Matrices scores were correlated negatively with the global FCD in multiple brain regions of the frontal, parietal, occipital, and temporal cortices in male participants. No significant correlation was found in female participants. Our findings confirmed the association between fluid reasoning and functional connectivity of multiple cognitive-related brain regions. The positive correlation with the functional connectivity strength and the negative correlation between fluid reasoning and FCD suggest that individuals with superior fluid reasoning capacity may possess a small number of strong functional connections. The sex dichotomy of this association indicates that the fluid reasoning capacity of men and women may have different neural substrates. PMID:25426825

Lang, Xu; Liu, Hao; Qin, Wen; Zhang, Yunting; Xuan, Yun; Yu, Chunshui

2015-01-01

162

Generating functions Moment generating functions  

E-print Network

generating functions MX(t) = E etX = x etx pX(x) X Bernoulli, parameter p MX(t) = et p + e0 q = pet + q X' & $ % Lecture 21 Generating functions Moment generating functions Moments and the MGF Sums of independent variables Characteristic functions Probability generating functions 1 #12;' & $ % Generating

Adler, Robert J.

163

Instrumented Functional Reach Test Differentiates Individuals at High Risk for Parkinson’s Disease from Controls  

PubMed Central

The functional reach (FR) test as a complex measure of balance including limits of stability has been proven to differentiate between patients with Parkinson’s disease (PD) and controls (CO). Recently, it has been shown that the instrumentation of the FR (iFR) with a wearable sensor may increase this diagnostic accuracy. This cross-sectional study aimed at investigating whether the iFR has the potential to differentiate individuals with high risk for PD (HRPD) from CO, as the delineation of such individuals would allow for, e.g., early neuromodulation. Thirteen PD patients, 13 CO, and 31 HRPD were investigated. HRPD was defined by presence of an enlarged area of hyperechogenicity in the mesencephalon on transcranial sonography and either one motor sign or two risk and prodromal markers of PD. All participants were asked to reach with their right arm forward as far as possible and hold this position for 10?s. During this period, sway parameters were assessed with an accelerometer (Dynaport, McRoberts) worn at the lower back. Extracted parameters that differed significantly between PD patients and CO in our cohort [FR distance (shorter in PD), anterior–posterior and mediolateral acceleration (both lower in PD)] as well as JERK, which has been shown to differentiate HRPD from CO and PD in a previous study, were included in a model, which was then used to differentiate HRPD from CO. The model yielded an area under the curve of 0.77, with a specificity of 85%, and a sensitivity of 74%. These results suggest that the iFR can contribute to an assessment panel focusing on the definition of HRPD individuals. PMID:25386137

Hasmann, Sandra E.; Berg, Daniela; Hobert, Markus A.; Weiss, David; Lindemann, Ulrich; Streffer, Johannes; Liepelt-Scarfone, Inga; Maetzler, Walter

2014-01-01

164

Does extending the dual-task functional exercises workout improve postural balance in individuals with ID?  

PubMed

Maintaining postural balance, overcoming visual and motor coordination disorders and experiencing problems with low general fitness - typical of intellectually disabled individuals - adversely affect the performance quality of their activities of daily living (ADLs). Physical fitness and postural balance can be improved by taking part in special intervention programs. Our study was designed to test whether extending the dual-task intervention program (combining ADLs with balance exercises on unstable surfaces) from 12 to 24 weeks additionally improved postural balance in individuals with intellectual disability (ID). We also attempted to assess whether the effects of the above intervention program were still noticeable after 8 weeks of holidays, in which participants did not take any rehabilitation exercises. A total of 34 adolescents, aged 14-16 years (15.06±0.9), with moderate ID took part in our study. The experimental group (E) consisted of 17 individuals, who continued the intervention program originated 3 months earlier, and the control group (C) comprised the same number of participants. Postural balance was assessed on a stabilometric platform Alfa. Having extended the workout period by another 12 weeks, we noticed that the path length of the center of pressure (COP) covered by participants on tests with their eyes open and closed significantly shortened. After a lapse of 8 weeks from the completion of the program, the experimental group revealed a statistically significant decrease in the velocity along the medio-lateral (M/L) and anterior-posterior (A/P) axes. The remaining variables stayed at the same level and the control group did not demonstrate any statistically significant changes. Dual-task exercises, in which enhancing functional tasks of daily living is combined with a parallel stimulation of balance reactions, may improve static balance in persons with ID. PMID:25553534

Mikolajczyk, Edyta; Jankowicz-Szymanska, Agnieszka

2015-03-01

165

Instrumented functional reach test differentiates individuals at high risk for Parkinson's disease from controls.  

PubMed

The functional reach (FR) test as a complex measure of balance including limits of stability has been proven to differentiate between patients with Parkinson's disease (PD) and controls (CO). Recently, it has been shown that the instrumentation of the FR (iFR) with a wearable sensor may increase this diagnostic accuracy. This cross-sectional study aimed at investigating whether the iFR has the potential to differentiate individuals with high risk for PD (HRPD) from CO, as the delineation of such individuals would allow for, e.g., early neuromodulation. Thirteen PD patients, 13 CO, and 31 HRPD were investigated. HRPD was defined by presence of an enlarged area of hyperechogenicity in the mesencephalon on transcranial sonography and either one motor sign or two risk and prodromal markers of PD. All participants were asked to reach with their right arm forward as far as possible and hold this position for 10?s. During this period, sway parameters were assessed with an accelerometer (Dynaport, McRoberts) worn at the lower back. Extracted parameters that differed significantly between PD patients and CO in our cohort [FR distance (shorter in PD), anterior-posterior and mediolateral acceleration (both lower in PD)] as well as JERK, which has been shown to differentiate HRPD from CO and PD in a previous study, were included in a model, which was then used to differentiate HRPD from CO. The model yielded an area under the curve of 0.77, with a specificity of 85%, and a sensitivity of 74%. These results suggest that the iFR can contribute to an assessment panel focusing on the definition of HRPD individuals. PMID:25386137

Hasmann, Sandra E; Berg, Daniela; Hobert, Markus A; Weiss, David; Lindemann, Ulrich; Streffer, Johannes; Liepelt-Scarfone, Inga; Maetzler, Walter

2014-01-01

166

A role for PHANTASTICA in medio-lateral regulation of adaxial domain development on tomato and tobacco leaves  

Technology Transfer Automated Retrieval System (TEKTRAN)

Diverse leaf forms in nature can be categorized into two groups: simple and compound. A simple leaf has a single blade unit, whilst a compound leaf is dissected into leaflets. For both simple and compound leaves, a MYB domain transcription factor PHANTASTICA (PHAN) plays an important role in establi...

167

Integer Functions  

NSDL National Science Digital Library

This page includes the encyclopedia entries for integer functions like rounding and congruence (e.g. floor, ceiling), GCD and LCM, Fibonaci and Lucas numbers, Euler and Bernoulli numbers, Stirling and Bell numbers, partitions and Tensorial functions.

168

Transfer Functions  

Microsoft Academic Search

In statistical time-series analysis, signal processing and control engineering, a transfer function is a mathematical relationship between a numerical input to a dynamic system and the resulting output. The theory of transfer functions describes how the input\\/output relationship is affected by the structure of the transfer function. The theory of the transfer functions of linear time-invariant (LTI) systems has been

David Stephen Pollock

2011-01-01

169

Inverse Functions  

NSDL National Science Digital Library

Created by Lang Moore and David Smith for the Connected Curriculum Project, this is a module to review concepts of inverse functions, and to use those concepts, together with functions defined by integrals, to develop inverse trigonometric functions. This is one within a much larger set of learning modules hosted by Duke University.

Moore, Lang

170

Function or not a Function  

NSDL National Science Digital Library

After completing this activity, students will understand the definition of a function and use it to identify whether or not an input-output pairing represents a function. Step by step instructions guide students in using their graphing calculators to determine if a graph represents a function by using a moving vertical line. A worksheet and teacher notes aid in teaching this lesson.

2011-11-28

171

Club Function  

NSDL National Science Digital Library

Students explore the definition of a function by playing an interactive game called "Club Function." The goal of the game is to be in the club! With students each assigned to be either a zebra or a rhinoceros, they group themselves according to the "rules" of the club function. After two minutes, students freeze in their groups, and if they are not correctly following the rules of the club function, then they are not allowed into the "club." Through this activity students come to understand that one x-coordinate can only have one corresponding y-coordinate while y-coordinates can have many x-coordinates that correspond to it.

2014-09-18

172

Function Junction  

NSDL National Science Digital Library

This activity teaches students about function transformations using f(x)=x and f(x)=x^2. Step by step instructions show students how to use their graphing calculators to explore the functions. A worksheet is included to test understanding of the lesson.

2008-11-04

173

Function Machine  

NSDL National Science Digital Library

This Java applet allows learners to explore simple linear functions. Students determine the algebraic form of a linear equation by entering inputs into the machine and by looking for patterns in the outputs. The function rules available are: integers from -10 to 10 are either added to, subtracted from, or multiplied by the input x to yield the output y.

2011-01-01

174

Functions Grapher  

NSDL National Science Digital Library

Discussing functions can be a tricky endeavor, but having a handy interactive way to talk about functions can relieve a great deal of stress. As part of the Mathematical Sciences Digital Library, this Functions Grapher application is designed to let users enter one or two functions. After doing so, users can trace along either one with coordinates shown dynamically changing at all times. The application was created by Professor Barbara Kaskosz of the University of Rhode Island, and it can be used by students in algebra, pre-calculus, or calculus courses. Of course, educators may wish to use it in their classrooms for illustrative purposes and they can also pass along to students who might find the very idea of functions and their operation a bit puzzling.

Kaskosz, Barbara

175

The evolutionary continuum of limb function from early theropods to birds  

NASA Astrophysics Data System (ADS)

The bipedal stance and gait of theropod dinosaurs evolved gradually along the lineage leading to birds and at some point(s), flight evolved. How and when did these changes occur? We review the evidence from neontology and palaeontology, including pectoral and pelvic limb functional morphology, fossil footprints/trackways and biomechanical models and simulations. We emphasise that many false dichotomies or categories have been applied to theropod form and function, and sometimes, these impede research progress. For example, dichotomisation of locomotor function into ‘non-avian’ and ‘avian’ modes is only a conceptual crutch; the evidence supports a continuous transition. Simplification of pelvic limb function into cursorial/non-cursorial morphologies or flexed/columnar poses has outlived its utility. For the pectoral limbs, even the classic predatory strike vs. flight wing-stroke distinction and separation of theropods into non-flying and flying—or terrestrial and arboreal—categories may be missing important subtleties. Distinguishing locomotor function between taxa, even with quantitative approaches, will always be fraught with ambiguity, making it difficult to find real differences if that ambiguity is properly acknowledged. There must be an ‘interpretive asymptote’ for reconstructing dinosaur limb function that available methods and evidence cannot overcome. We may be close to that limit, but how far can it be stretched with improved methods and evidence, if at all? The way forward is a combination of techniques that emphasises integration of neontological and palaeontological evidence and quantitative assessment of limb function cautiously applied with validated techniques and sensitivity analysis of unknown variables.

Hutchinson, John R.; Allen, Vivian

2009-04-01

176

Turning Semicircular Canal Function on Its Head: Dinosaurs and a Novel Vestibular Analysis  

PubMed Central

Previous investigations have correlated vestibular function to locomotion in vertebrates by scaling semicircular duct radius of curvature to body mass. However, this method fails to discriminate bipedal from quadrupedal non-avian dinosaurs. Because they exhibit a broad range of relative head sizes, we use dinosaurs to test the hypothesis that semicircular ducts scale more closely with head size. Comparing the area enclosed by each semicircular canal to estimated body mass and to two different measures of head size, skull length and estimated head mass, reveals significant patterns that corroborate a connection between physical parameters of the head and semicircular canal morphology. Head mass more strongly correlates with anterior semicircular canal size than does body mass and statistically separates bipedal from quadrupedal taxa, with bipeds exhibiting relatively larger canals. This morphologic dichotomy likely reflects adaptations of the vestibular system to stability demands associated with terrestrial locomotion on two, versus four, feet. This new method has implications for reinterpreting previous studies and informing future studies on the connection between locomotion type and vestibular function. PMID:23516495

Georgi, Justin A.; Sipla, Justin S.; Forster, Catherine A.

2013-01-01

177

Function Machine  

NSDL National Science Digital Library

This Java activity for the interactive white board (free access with registration) provides learners an opportunity to explore number functions and to predict outcomes. Teachers set the desired function from the drop-down list (double it, halve it, add 1, subtract 1, add 10, or subtract 10) and choose the start number from 1-20. Students are asked to predict the outcome before asking the machine to go. There is an option to hide the function so the teacher can ask students to work out what operation is being used to get from the starting number to the number generated.

2012-07-19

178

Glycosphingolipid Functions  

PubMed Central

The combination of carbohydrate and lipid generates unusual molecules in which the two distinctive halves of the glycoconjugate influence the function of each other. Membrane glycolipids can act as primary receptors for carbohydrate binding proteins to mediate transmembrane signaling despite restriction to the outer bilayer leaflet. The extensive heterogeneity of the lipid moiety plays a significant, but still largely unknown, role in glycosphingolipid function. Potential interplay between glycolipids and their fatty acid isoforms, together with their preferential interaction with cholesterol, generates a complex mechanism for the regulation of their function in cellular physiology. PMID:21555406

Lingwood, Clifford A.

2011-01-01

179

The Middle Miocene ape Pierolapithecus catalaunicus exhibits extant great ape-like morphometric affinities on its patella: inferences on knee function and evolution.  

PubMed

The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional behavior and locomotion of these taxa based on isolated elements only. The fossil great ape Pierolapithecus catalaunicus (IPS 21350 skeleton; 11.9 Ma) exhibits a relatively wide and shallow thorax with moderate hand length and phalangeal curvature, dorsally-oriented metacarpophalangeal joints, and loss of ulnocarpal articulation. This evidence reveals enhanced orthograde postures without modern ape-like below-branch suspensory adaptations. Therefore, it has been proposed that natural selection enhanced vertical climbing (and not suspension per se) in Pierolapithecus catalaunicus. Although limb long bones are not available for this species, its patella (IPS 21350.37) can potentially provide insights into its knee function and thus on the complexity of its total morphological pattern. Here we provide a detailed description and morphometric analyses of IPS 21350.37, which are based on four external dimensions intended to capture the overall patellar shape. Our results reveal that the patella of Pierolapithecus is similar to that of extant great apes: proximodistally short, mediolaterally broad and anteroposteriorly thin. Previous biomechanical studies of the anthropoid knee based on the same measurements proposed that the modern great ape patella reflects a mobile knee joint while the long, narrow and thick patella of platyrrhine and especially cercopithecoid monkeys would increase the quadriceps moment arm in knee extension during walking, galloping, climbing and leaping. The patella of Pierolapithecus differs not only from that of monkeys and hylobatids, but also from that of basal hominoids (e.g., Proconsul and Nacholapithecus), which display slightly thinner patellae than extant great apes (the previously-inferred plesiomorphic hominoid condition). If patellar shape in Pierolapithecus is related to modern great ape-like knee function, our results suggest that increased knee mobility might have originally evolved in relation to enhanced climbing capabilities in great apes (such as specialized vertical climbing). PMID:24637777

Pina, Marta; Almécija, Sergio; Alba, David M; O'Neill, Matthew C; Moyà-Solà, Salvador

2014-01-01

180

The Middle Miocene Ape Pierolapithecus catalaunicus Exhibits Extant Great Ape-Like Morphometric Affinities on Its Patella: Inferences on Knee Function and Evolution  

PubMed Central

The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional behavior and locomotion of these taxa based on isolated elements only. The fossil great ape Pierolapithecus catalaunicus (IPS 21350 skeleton; 11.9 Ma) exhibits a relatively wide and shallow thorax with moderate hand length and phalangeal curvature, dorsally-oriented metacarpophalangeal joints, and loss of ulnocarpal articulation. This evidence reveals enhanced orthograde postures without modern ape-like below-branch suspensory adaptations. Therefore, it has been proposed that natural selection enhanced vertical climbing (and not suspension per se) in Pierolapithecus catalaunicus. Although limb long bones are not available for this species, its patella (IPS 21350.37) can potentially provide insights into its knee function and thus on the complexity of its total morphological pattern. Here we provide a detailed description and morphometric analyses of IPS 21350.37, which are based on four external dimensions intended to capture the overall patellar shape. Our results reveal that the patella of Pierolapithecus is similar to that of extant great apes: proximodistally short, mediolaterally broad and anteroposteriorly thin. Previous biomechanical studies of the anthropoid knee based on the same measurements proposed that the modern great ape patella reflects a mobile knee joint while the long, narrow and thick patella of platyrrhine and especially cercopithecoid monkeys would increase the quadriceps moment arm in knee extension during walking, galloping, climbing and leaping. The patella of Pierolapithecus differs not only from that of monkeys and hylobatids, but also from that of basal hominoids (e.g., Proconsul and Nacholapithecus), which display slightly thinner patellae than extant great apes (the previously-inferred plesiomorphic hominoid condition). If patellar shape in Pierolapithecus is related to modern great ape-like knee function, our results suggest that increased knee mobility might have originally evolved in relation to enhanced climbing capabilities in great apes (such as specialized vertical climbing). PMID:24637777

Pina, Marta; Almécija, Sergio; Alba, David M.; O'Neill, Matthew C.; Moyà-Solà, Salvador

2014-01-01

181

Effect of Transcranial Direct-Current Stimulation Combined with Treadmill Training on Balance and Functional Performance in Children with Cerebral Palsy: A Double-Blind Randomized Controlled Trial  

PubMed Central

Background Cerebral palsy refers to permanent, mutable motor development disorders stemming from a primary brain lesion, causing secondary musculoskeletal problems and limitations in activities of daily living. The aim of the present study was to determine the effects of gait training combined with transcranial direct-current stimulation over the primary motor cortex on balance and functional performance in children with cerebral palsy. Methods A double-blind randomized controlled study was carried out with 24 children aged five to 12 years with cerebral palsy randomly allocated to two intervention groups (blocks of six and stratified based on GMFCS level (levels I-II or level III).The experimental group (12 children) was submitted to treadmill training and anodal stimulation of the primary motor cortex. The control group (12 children) was submitted to treadmill training and placebo transcranial direct-current stimulation. Training was performed in five weekly sessions for 2 weeks. Evaluations consisted of stabilometric analysis as well as the administration of the Pediatric Balance Scale and Pediatric Evaluation of Disability Inventory one week before the intervention, one week after the completion of the intervention and one month after the completion of the intervention. All patients and two examiners were blinded to the allocation of the children to the different groups. Results The experimental group exhibited better results in comparison to the control group with regard to anteroposterior sway (eyes open and closed; p<0.05), mediolateral sway (eyes closed; p<0.05) and the Pediatric Balance Scale both one week and one month after the completion of the protocol. Conclusion Gait training on a treadmill combined with anodal stimulation of the primary motor cortex led to improvements in static balance and functional performance in children with cerebral palsy. Trial Registration Ensaiosclinicos.gov.br/RBR-9B5DH7 PMID:25171216

Duarte, Natália de Almeida Carvalho; Grecco, Luanda André Collange; Galli, Manuela; Fregni, Felipe; Oliveira, Cláudia Santos

2014-01-01

182

MULTIVARIATE OUTLYINGNESS FUNCTIONS MAHALANOBIS TYPE OUTLYINGNESS FUNCTIONS  

E-print Network

OUTLINE MULTIVARIATE OUTLYINGNESS FUNCTIONS MAHALANOBIS TYPE OUTLYINGNESS FUNCTIONS ADDITION MULTIVARIATE OUTLYINGNESS FUNCTIONS MAHALANOBIS TYPE OUTLYINGNESS FUNCTIONS ADDITION AND REPLACEMENT BREAKDOWN of Outlyingness Functions on Rd On Mahalanobis Type Outlyingness Functions On Addition Versus Replacement

Serfling, Robert

183

Functional quantization  

E-print Network

Data is rarely obtained for its own sake; oftentimes, it is a function of the data that we care about. Traditional data compression and quantization techniques, designed to recreate or approximate the data itself, gloss ...

Misra, Vinith

2008-01-01

184

Linear Functions  

NSDL National Science Digital Library

In this tutorial, "Linear functions of the form f(x) = ax + b and the properties of their graphs are explored interactively using an applet." The applet allows students to manipulate variables to discover the changes in intercepts and slope of the graphed line. There are six questions for students to answer, exploring the applet and observing changes. The questions' answers are included on this site. Additionally, a tutorial for graphing linear functions by hand is included.

Shodor

2012-03-29

185

Transfer functions  

NASA Technical Reports Server (NTRS)

The vulnerability of electronic equipment to carbon fibers is studied. The effectiveness of interfaces, such as filters, doors, window screens, and cabinets, which affect the concentration, exposure, or deposition of carbon fibers on both (internal and external) sides of the interface is examined. The transfer function of multilayer aluminum mesh, wet and dry, polyurethane foam, and window screen are determined as a function of air velocity. FIlters installed in typical traffic control boxes and air conditioners are also considered.

Taback, I.

1979-01-01

186

Determine Optimal Stimulus Amplitude for Using Vestibular Stochastic Stimulation to Improve Balance Function  

NASA Technical Reports Server (NTRS)

Sensorimotor changes such as postural and gait instabilities can affect the functional performance of astronauts when they transition across different gravity environments. We are developing a method, based on stochastic resonance (SR), to enhance information transfer by applying non-zero levels of external noise on the vestibular system (vestibular stochastic resonance, VSR). Our previous work has shown the advantageous effects of VSR in a balance task of standing on an unstable surface [1]. This technique to improve detection of vestibular signals uses a stimulus delivery system that provides imperceptibly low levels of white noise-based binaural bipolar electrical stimulation of the vestibular system. The goal of this project is to determine optimal levels of stimulation for SR applications by using a defined vestibular threshold of motion detection. A series of experiments were carried out to determine a robust paradigm to identify a vestibular threshold that can then be used to recommend optimal stimulation levels for sensorimotor adaptability (SA) training applications customized to each crewmember. The amplitude of stimulation to be used in the VSR application has varied across studies in the literature such as 60% of nociceptive stimulus thresholds [2]. We compared subjects' perceptual threshold with that obtained from two measures of body sway. Each test session was 463s long and consisted of several 15s long sinusoidal stimuli, at different current amplitudes (0-2 mA), interspersed with 20-20.5s periods of no stimulation. Subjects sat on a chair with their eyes closed and had to report their perception of motion through a joystick. A force plate underneath the chair recorded medio-lateral shear forces and roll moments. Comparison of threshold of motion detection obtained from joystick data versus body sway suggests that perceptual thresholds were significantly lower. In the balance task, subjects stood on an unstable surface and had to maintain balance, and the stimulation was administered from 20-400% of subjects' vestibular threshold. Optimal stimulation amplitude was determined at which the balance performance was best compared to control (no stimulation). Preliminary results show that, in general, using stimulation amplitudes at 40-60% of perceptual motion threshold significantly improved the balance performance. We hypothesize that VSR stimulation will act synergistically with SA training to improve adaptability by increasing utilization of vestibular information and therefore will help us to optimize and personalize a SA countermeasure prescription. This combination may help to significantly reduce the number of days required to recover functional performance to preflight levels after long-duration spaceflight.

Goel, R.; Kofman, I.; DeDios, Y. E.; Jeevarajan, J.; Stepanyan, V.; Nair, M.; Congdon, S.; Fregia, M.; Cohen, H.; Bloomberg, J.J.; Mulavara, A.P.

2015-01-01

187

Riemann-Hypothesis Millennium-Problem(MP) Physics Proof via CATEGORY-SEMANTICS(C-S)/F=C Aristotle SQUARE-of-OPPOSITION(SoO) DEduction-LOGIC DichotomY  

NASA Astrophysics Data System (ADS)

Riemann-hypothesis physics-proof combines: Siegel-Antonoff-Smith[AMS Joint Mtg.(2002)-Abs.973-03-126] digits on-average statistics HIll[Am. J. Math 123, 3, 887(1996)] logarithm-function's (1,0)-fixed-point base=units=scale-invariance proven Newcomb[Am. J. Math. 4, 39(1881)]-Weyl[Goett. Nachr.(1914); Math. Ann. 7, 313(1916)]-Benford[Proc. Am. Phil. Soc. 78, 4, 51(1938)]-law [Kac, Math. of Stat.-Reasoning(1955); Raimi, Sci. Am. 221, 109(1969)] algebraic-inversion to ONLY Bose-Einstein quantum-statistics(BEQS) with digit d = 0 gapFUL Bose-Einstein Condensation(BEC) insight that digits are quanta are bosons were always digits, via Siegel-Baez category-semantics tabular list-format matrix truth-table analytics in Plato-Aristotle classic "square-of-opposition" : FUZZYICS=CATEGORYICS/Category-Semantics, with Goodkind Bose-Einstein condensation(BEC) ABOVE ground-state with/and Rayleigh(cut-limit of "short-cut method";1870)-Polya(1922)-"Anderson"(1958) localization [Doyle and Snell, Random-Walks and Electrical-Networks, MAA(1981)-p.99-100!!!].

Baez, J.; Lapidaryus, M.; Carl-Ludwig Siegel, Edward

2011-03-01

188

Riemann-Hypothesis Millennium-Problem(MP) Physics Proof via CATEGORY-SEMANTICS(C-S)/F=C Aristotle SQUARE-of-OPPOSITION(SoO) DEduction-LOGIC DichotomY  

NASA Astrophysics Data System (ADS)

Riemann-hypothesis physics-proof combines: Siegel-Antono-Smith[AMS Joint Mtg.(2002)- Abs.973-03-126] digits on-average statistics HIll[Am. J. Math 123, 3, 887(1996)] logarithm-function's (1,0)- xed-point base=units=scale-invariance proven Newcomb [Am. J. Math. 4, 39(1881)]-Weyl[Goett. Nachr.(1914); Math. Ann.7, 313(1916)]-Benford[Proc. Am. Phil. Soc. 78, 4, 51(1938)]-law [Kac,Math. of Stat.-Reasoning(1955); Raimi, Sci. Am. 221, 109(1969)] algebraic-inversion to ONLY Bose-Einstein quantum-statistics(BEQS) with digit d = 0 gapFUL Bose-Einstein Condensation(BEC) insight that digits are quanta are bosons because bosons are and always were quanta are and always were digits, via Siegel-Baez category-semantics tabular list-format matrix truth-table analytics in Plato-Aristotle classic "square-of-opposition" : FUZZYICS=CATEGORYICS/Category-Semantics, with Goodkind Bose-Einstein Condensation (BEC) ABOVE ground-state with/and Rayleigh(cut-limit of "short-cut method";1870)-Polya(1922)-"Anderson"(1958) localization [Doyle and Snell,Random-Walks and Electrical-Networks, MAA(1981)-p.99-100!!!] in Brillouin[Wave-Propagation in Periodic-Structures(1946) Dover(1922)]-Hubbard-Beeby[J.Phys.C(1967)] Siegel[J.Nonxline-Sol.40,453(1980)] generalized-disorder collective-boson negative-dispersion mode-softening universality-principle(GP) first use of the ``square-of-opposition'' in physics since Plato and Aristote!!!

Baez, Joao-Joan; Lapidaryus, Michelle; Carl-Ludwig Siegel, Edward

2013-03-01

189

Graphic functions  

Microsoft Academic Search

Reviews 13 publications (1910-1911), dealing with the psychology of graphic functions. There has been an increasing practical interest in writing and drawing activities. The studies focus upon the pedagogy of drawing and writing, methods of studying handwriting, conventional beliefs of graphology, unconscious imitations in handwriting, control of voluntary movements, factors of consciousness in the learning process and spatial dislocations.

June E. Downey

1911-01-01

190

Functional hyposplenism  

PubMed Central

Abstract Functional hyposplenism is a condition accompanying many diseases such as sickle cell disease, celiac disease, alcoholic liver disease, hepatic cirrhosis, lymphomas and autoimmune disorders. It is characterised mostly by defective immune responses against infectious agents, especially encapsulated organisms, since the spleen is thought to play an important role in the production and maturation of B-memory lymphocytes and other substances like opsonins, both of which are considered crucial elements of the immune system for fighting infections. It is also associated with thrombocytosis, which might lead to thromboembolic events. Functional hyposplenism is diagnosed by the presence of Howell-Jolly bodies and pitted erythrocytes in the peripheral blood smear, and by nuclear imaging modalities such as spleen scintigraphy with the use of Technetium-99m and/or spleen scintigraphy with the use of heat-damaged Technetium-99m labeled erythrocytes. Severe infections accompanying functional hyposplenism can lead to the overwhelming post infection syndrome, which can often be fatal. Identifying patients with functional hyposplenism is important because simple measures such as vaccination against common infective microorganisms (e.g. Streptococcus pneumonia, Neisseria meningitides and Haemophilous influenzae) and antibiotic therapy when needed are considered beneficial in diminishing the frequency and gravity of the infections accompanying the syndrome. PMID:25125944

Kirkineska, L; Perifanis, V; Vasiliadis, T

2014-01-01

191

Pedotransfer Functions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Often, there is a need to estimate parameters governing retention and transport of water and chemicals in soils from other, readily available data. Equations expressing relationships between soil properties were proposed to be called pedotransfer functions. This entry provides the overview of the st...

192

Function flyer  

NSDL National Science Digital Library

Teachers of all algebra levels will find this applet useful when helping students understand and visualize the relationship between an equation and its graph. Assigning the applet with exploration questions to small groups of students would be an excellent introduction to how the applet works and good preparation for more in-depth exploration of issues related to whatever types of functions the class is studying.

Shodor Education Foundation

2004-01-01

193

Ong & Tzevelekos Functional Reachability 1 Functional Reachability  

E-print Network

Ong & Tzevelekos Functional Reachability ­ 1 Functional Reachability Luke Ong Nikos Tzevelekos Tree Automata Conclusion and on Ong & Tzevelekos Functional Reachability ­ 2 Reachability in functional and on Ong & Tzevelekos Functional Reachability ­ 2 Reachability in functional computation. s Consider a term

194

Cellular mechanisms of mutations in Kv7.1: auditory functions in Jervell and Lange-Nielsen syndrome vs. Romano-Ward syndrome.  

PubMed

As a result of cell-specific functions of voltage-activated K(+) channels, such as Kv7.1, mutations in this channel produce profound cardiac and auditory defects. At the same time, the massive diversity of K(+) channels allows for compensatory substitution of mutant channels by other functional channels of their type to minimize defective phenotypes. Kv7.1 represents a clear example of such functional dichotomy. While several point mutations in the channel result in a cardio-auditory syndrome called Jervell and Lange-Nielsen syndrome (JLNS), about 100-fold mutations result in long QT syndrome (LQTS) denoted as Romano-Ward syndrome (RWS), which has an intact auditory phenotype. To determine whether the cellular mechanisms for the diverse phenotypic outcome of Kv7.1 mutations, are dependent on the tissue-specific function of the channel and/or specialized functions of the channel, we made series of point mutations in hKv7.1 ascribed to JLNS and RWS. For JLNS mutations, all except W248F yielded non-functional channels when expressed alone. Although W248F at the end of the S4 domain yielded a functional current, it underwent marked inactivation at positive voltages, rendering the channel non-functional. We demonstrate that by definition, none of the JLNS mutants operated in a dominant negative (DN) fashion. Instead, the JLNS mutants have impaired membrane trafficking, trapped in the endoplasmic reticulum (ER) and Cis-Golgi. The RWS mutants exhibited varied functional phenotypes. However, they can be summed up as exhibiting DN effects. Phenotypic differences between JLNS and RWS may stem from tissue-specific functional requirements of cardiac vs. inner ear non-sensory cells. PMID:25705178

Mousavi Nik, Atefeh; Gharaie, Somayeh; Jeong Kim, Hyo

2015-01-01

195

Executive functions.  

PubMed

Executive functions (EFs) make possible mentally playing with ideas; taking the time to think before acting; meeting novel, unanticipated challenges; resisting temptations; and staying focused. Core EFs are inhibition [response inhibition (self-control--resisting temptations and resisting acting impulsively) and interference control (selective attention and cognitive inhibition)], working memory, and cognitive flexibility (including creatively thinking "outside the box," seeing anything from different perspectives, and quickly and flexibly adapting to changed circumstances). The developmental progression and representative measures of each are discussed. Controversies are addressed (e.g., the relation between EFs and fluid intelligence, self-regulation, executive attention, and effortful control, and the relation between working memory and inhibition and attention). The importance of social, emotional, and physical health for cognitive health is discussed because stress, lack of sleep, loneliness, or lack of exercise each impair EFs. That EFs are trainable and can be improved with practice is addressed, including diverse methods tried thus far. PMID:23020641

Diamond, Adele

2013-01-01

196

Wetland Functions  

NSDL National Science Digital Library

This resource explains a number of critical functions performed by wetlands. Students will discover that wetlands moderate impacts from flooding, control erosion, purify water, and provide habitat for fish and wildlife. They also provide a unique natural environment for people to enjoy outdoor recreation activities. It is part of a module that aims to help students get to know the complexities of wetlands, discover wildlife, enjoy the experience of being outdoors, and learn how necessary wetlands are to the health of our environment. Although it is about wetlands in New England for educators and their middle school students, it suggests ways to study wetland characteristics, why wetlands are important, and how students and teachers can help protect a local wetland in any part of the country. An associated set of activities is also available.

197

Executive Functions  

PubMed Central

Executive functions (EFs) make possible mentally playing with ideas; taking the time to think before acting; meeting novel, unanticipated challenges; resisting temptations; and staying focused. Core EFs are inhibition [response inhibition (self-control—resisting temptations and resisting acting impulsively) and interference control (selective attention and cognitive inhibition)], working memory, and cognitive flexibility (including creatively thinking “outside the box,” seeing anything from different perspectives, and quickly and flexibly adapting to changed circumstances). The developmental progression and representative measures of each are discussed. Controversies are addressed (e.g., the relation between EFs and fluid intelligence, self-regulation, executive attention, and effortful control, and the relation between working memory and inhibition and attention). The importance of social, emotional, and physical health for cognitive health is discussed because stress, lack of sleep, loneliness, or lack of exercise each impair EFs. That EFs are trainable and can be improved with practice is addressed, including diverse methods tried thus far. PMID:23020641

Diamond, Adele

2014-01-01

198

A Magnetic Perspective on the Martian Crustal Dichotomy  

NASA Technical Reports Server (NTRS)

The Mars Global Surveyor spacecraft has completed two Mars years in nearly circular polar orbit at a nominal altitude of 400 km. The Mars crust is at least an order of magnitude more intensely magnetized than that of the Earth, and intriguing in both its global distribution and geometric properties. Measurements of the vector magnetic field have been used to map the magnetic field of crustal origin to high accuracy. This most recent map is assembled from > 2 full years of MGS night-side observations, and uses along-track filtering to greatly reduce noise due to external field variations. Additional information is included in the original extended abstract.

Connerney, J. E. P.; Acuna, M. H.; Ness, N. F.; Mitchell, D. L.; Lin, R. P.; Reme, H.

2004-01-01

199

A false dichotomy? Mental illness and lone-actor terrorism.  

PubMed

We test whether significant differences in mental illness exist in a matched sample of lone- and group-based terrorists. We then test whether there are distinct behavioral differences between lone-actor terrorists with and without mental illness. We then stratify our sample across a range of diagnoses and again test whether significant differences exist. We conduct a series of bivariate, multivariate, and multinomial statistical tests using a unique dataset of 119 lone-actor terrorists and a matched sample of group-based terrorists. The odds of a lone-actor terrorist having a mental illness is 13.49 times higher than the odds of a group actor having a mental illness. Lone actors who were mentally ill were 18.07 times more likely to have a spouse or partner who was involved in a wider movement than those without a history of mental illness. Those with a mental illness were more likely to have a proximate upcoming life change, more likely to have been a recent victim of prejudice, and experienced proximate and chronic stress. The results identify behaviors and traits that security agencies can utilize to monitor and prevent lone-actor terrorism events. The correlated behaviors provide an image of how risk can crystalize within the individual offender and that our understanding of lone-actor terrorism should be multivariate in nature. PMID:25133916

Corner, Emily; Gill, Paul

2015-02-01

200

The Multilingual/Bilingual Dichotomy: An Exploration of Individual Differences  

ERIC Educational Resources Information Center

Bilingualism (Sanz, 2000), motivation (Pintrich, 1989), and language aptitude (Grigorenko, Sternberg, and Ehrman, 2000) are crucial individual differences that contribute to successful adult language learning. Since Gardner's (1985) seminal work on motivation, many studies have shown that motivation is dynamic and that it affects language…

Thompson, Amy S.

2009-01-01

201

The flexibility–complementarity dichotomy in receptor–ligand interactions  

E-print Network

. Complexes that can make ond acceptor located at the same position on the ligand framework but itional rotor, and (c) two additional rotors. The key rotatable bonds are Chemical Science Edge Article O pe n A cc es s A rti cl e. P ub lis he d on 1 5 D ec... with dichloromethane–methanol (100 : 0 to 95 : 5). The product was isolated as a colorless oil (0.19 g, 9%); 1H NMR (400 MHz, CDCl3): dH ¼ 8.54 (d, 1H, J ¼ 2), 8.49 (dd, 1H, J ¼ 5, J ¼ 2), 7.70 (dt, 1H, J ¼ 8, J ¼ 2), 7.24 (dd, 1H, J ¼ 8, J ¼ 5), 4.59 (s, 2H), 4.14 (s...

Sun, Hongmei; Hunter, Christopher A.; Llamas, Eva Marina

2014-12-15

202

Unmasking Moral Dichotomies: Can Feminist Pedagogy Overcome Student Resistance?  

ERIC Educational Resources Information Center

Scholarship on feminist pedagogy suggests that challenges to traditional forms of knowledge help university students overcome resistance to discussions about oppression. Because students assume that 'truth' is objective, they are unwilling to consider alternative voices from the 'margins'. This paper theoretically argues and empirically examines…

Markowitz, Linda

2005-01-01

203

Avoiding Moral Dichotomies: Teaching Controversial Topics to Resistant Students.  

ERIC Educational Resources Information Center

Argues that student classroom resistance to the analysis of social inequality and other controversial topics commonly involves their application of norm/other logic to course material. Provides lecture topics, in-class exercises, and homework assignments to assist teachers in helping their students overcome the limitations in norm/other logic.…

Markowitz, Linda; Hedley, Mark

2001-01-01

204

Dichotomy and perceptual distortions in absolute pitch ability  

PubMed Central

Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a “perceptual magnet” centered at the note “A.” In addition, we document a gradual decline in pitch-naming accuracy with age, characterized by a perceptual shift in the “sharp” direction. These findings speak both to the process of acquisition of AP and to its stability. PMID:17724340

Athos, E. Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane

2007-01-01

205

The Rural Education Dichotomy: Disadvantaged Systems and School Strengths.  

ERIC Educational Resources Information Center

The educational advantages conferred by rurality and smallness have their greatest impact at the school and classroom level, but this same rurality creates district or system-level problems that have often been solved by consolidation. Consolidation efforts have been waning because they are politically unpopular, good economic times allow states…

Dunn, Randy J.

206

Ethical dichotomies in organ transplantation a time for bridge building  

Microsoft Academic Search

Rapid advances of the past 15 years have resolved many of the technical and immunologic limitations to organ transplantation. With the success rates that can now be achieved, there is increased attention to the limited supply of donor organs and to cost considerations, the remaining obstacles to wide application of organ transplantation. Competition for organs and for funding demands greater

Owen S. Surman; A. Benedict Cosimi

1996-01-01

207

Educating Moral Emotions or Moral Selves: A False Dichotomy?  

ERIC Educational Resources Information Center

In the post-Kohlbergian era of moral education, a "moral gap" has been identified between moral cognition and moral action. Contemporary moral psychologists lock horns over how this gap might be bridged. The two main contenders for such bridge-building are moral emotions and moral selves. I explore these two options from an Aristotelian…

Kristjansson, Kristjan

2010-01-01

208

Managerial Intuition across Cultures: Beyond a "West-East Dichotomy"  

ERIC Educational Resources Information Center

Purpose: Studies investigating intuition from a cultural and cross-cultural perspective have a long tradition in various disciplines but, due to the increased internationalization of business, an understanding of the mental lives of other cultures became one of the priorities of management practitioners and theoreticians. Cultures of…

Wozniak, Anna

2006-01-01

209

Content vs. Learning: An Old Dichotomy in Science Courses  

ERIC Educational Resources Information Center

The principles of course redesign that were applied to a gateway Cell Biology course at the University of Wisconsin-Milwaukee are applicable to courses large and small, and to institutions of any size. The challenge was to design a content-rich science course that kept pace with present and future content and at the same time use principles of…

Bergtrom, Gerald

2011-01-01

210

DICHOTOMY THEOREMS FOR HOLANT PROBLEMS (DRAFT V0.7)  

E-print Network

capacity two years ago, it was a turning point in my graduate career; I never would have expected and scrutinize my work when I could make it back to Madison. It is amazing how just a few bits of good advice Sciences) at the UNIVERSITY OF WISCONSIN­MADISON 2010 #12;i To my wife Dea -- married eight years and going

Cai, Jin-Yi

211

In Defense of the Substance-Procedure Dichotomy  

Microsoft Academic Search

John Hart Ely famously observed, “We were all brought up on sophisticated talk about the fluidity of the line between substance and procedure,” but for most of Erie’s history, the Supreme Court has answered the question “Does this state law govern in federal court?” with a “yes” or a “no.” Beginning, however, with Gasperini v. Center for Humanities, and continuing

Jennifer S. Hendricks

2011-01-01

212

Inherent contradictions in the tunneling-multiphoton dichotomy  

SciTech Connect

Strong-field phenomena are currently described as being multiphoton or tunneling, based on whether the Keldysh parameter {gamma} is greater than or less than unity. There are disqualifying features in this categorization. It is specific to the length gauge, dependent on only one intensity parameter, and backward in the sense that ionization with {gamma}>>1 can occur only by tunneling, and ionization with {gamma}<<1 must be over the barrier, and hence is not achieved by tunneling. As {gamma} becomes smaller, ionization becomes increasingly distant from tunneling, and eventually reaches conditions where the dipole approximation fails and there is no meaningful scalar-potential diagram at all.

Reiss, H. R. [Max Born Institute, 12489 Berlin, Germany and American University, Washington, DC 20016-8058 (United States)

2007-03-15

213

Tolerance to Alliance: Deconstructing Dichotomies to Advocate for All Students  

ERIC Educational Resources Information Center

This article argues that teachers in the twenty-first century need to incorporate queer theory into their teaching practice and their discussions about individual differences in order to advocate for those students most likely to be bullied in schools. It provides a brief background on queer theory, gives an introduction to central ideas of the…

Berg, Margaret

2013-01-01

214

Dichotomy of protective cellular immune responses to human visceral leishmaniasis.  

PubMed

Healing/protective responses in human visceral leishmaniasis (VL) are associated with stimulation/production of Th1 cytokines, such as interferon IFN-gamma, and conversion in the leishmanin skin test (LST). Such responses were studied for 90 days in 44 adult healthy volunteers from VL non-endemic areas, with no past history of VL/cutaneous leishmaniasis (CL) and LST non-reactivity following injection with one of four doses of Alum-precipitated autoclaved Leishmania major (Alum/ALM) +/- bacille Calmette-Guerin (BCG), a VL candidate vaccine. The vaccine was well tolerated with minimal localized side-effects and without an increase in antileishmanial antibodies or interleukin (IL)-5. Five volunteers (5/44; 11.4%) had significant IFN-gamma production by peripheral blood mononuclear cells (PBMCs) in response to Leishmania antigens in their prevaccination samples (P = 0.001) but were LST non-reactive. On day 45, more than half the volunteers (26/44; 59.0%) had significantly high LST indurations (mean 9.2 +/- 2.7 mm) and high IFN-gamma levels (mean 1008 +/- 395; median 1247 pg/ml). Five volunteers had significant L. donovani antigen-induced IFN-gamma production (mean 873 +/- 290; median 902; P = 0.001), but were non-reactive in LST. An additional five volunteers (5/44; 11.4%) had low IFN-gamma levels (mean 110 +/- 124 pg/ml; median 80) and were non-reactive in LST (induration = 00 mm). The remaining eight volunteers had low IFN-gamma levels, but significant LST induration (mean 10 +/- 2.9 mm; median 11). By day 90 the majority of volunteers (27/44; 61.4%) had significant LST induration (mean 10.8 +/- 9.9 mm; P < 0.001), but low levels of L. donovani antigen-induced IFN-gamma (mean 66.0 +/- 62 pg/ml; P > 0.05). Eleven volunteers (11/44; 25%) had significantly high levels of IFN-gamma and LST induration, while five volunteers had low levels of IFN-gamma (<100 pg/ml) and no LST reactivity (00 mm). One volunteer was lost to follow-up. In conclusion, it is hypothesized that cellular immune responses to human VL are dichotomatous, and that IFN-gamma production and the LST response are not in a causal relationship. Following vaccination and probably cure of VL infection, the IFN-gamma response declines with time while the LST response persists. LST is a simple test that can be used to assess candidate vaccine efficacy. PMID:15807861

Khalil, E A G; Ayed, N B; Musa, A M; Ibrahim, M E; Mukhtar, M M; Zijlstra, E E; Elhassan, I M; Smith, P G; Kieny, P M; Ghalib, H W; Zicker, F; Modabber, F; Elhassan, A M

2005-05-01

215

The dichotomy of pathogens and allergens in vaccination approaches  

PubMed Central

Traditional prophylactic vaccination to prevent illness is the primary objective of many research activities worldwide. The golden age of vaccination began with an approach called variolation in ancient China and the evolution of vaccines still continues today with modern developments such as the production of GardasilTM against HPV and cervical cancer. The historical aspect of how different forms of vaccination have changed the face of medicine and communities is important as it dictates our future approaches on both a local and global scale. From the eradication of smallpox to the use of an experimental vaccine to save a species, this review will explore these successes in infectious disease vaccination and also discuss a few significant failures which have hampered our efforts to eradicate certain diseases. The second part of the review will explore designing a prophylactic vaccine for the growing global health concern that is allergy. Allergies are an emerging global health burden. Of particular concern is the rise of food allergies in developed countries where 1 in 10 children is currently affected. The formation of an allergic response results from the recognition of a foreign component by our immune system that is usually encountered on a regular basis. This may be a dust-mite or a prawn but this inappropriate immune response can result in a life-time of food avoidance and lifestyle restrictions. These foreign components are very similar to antigens derived from infectious pathogens. The question arises: should the allergy community be focussing on protective measures rather than ongoing therapeutic interventions to deal with these chronic inflammatory conditions? We will explore the difficulties and benefits of prophylactic vaccination against various allergens by means of genetic technology that will dictate how vaccination against allergens could be utilized in the near future. PMID:25076945

Baird, Fiona J.; Lopata, Andreas L.

2014-01-01

216

Dichotomy and perceptual distortions in absolute pitch ability.  

PubMed

Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a "perceptual magnet" centered at the note "A." In addition, we document a gradual decline in pitch-naming accuracy with age, characterized by a perceptual shift in the "sharp" direction. These findings speak both to the process of acquisition of AP and to its stability. PMID:17724340

Athos, E Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane

2007-09-11

217

Assessing Function and Functional Outcome in Schizophrenia  

Microsoft Academic Search

\\u000a The diagnosis of schizophrenia can only be made in the presence of a loss of functioning in domains such as employment, independent\\u000a living, and social functioning. Accurately measuring functioning is central to research on the course of the disorder, treatment\\u000a and rehabilitation outcomes, and biosocial factors in schizophrenia. Assessments of functional disability have described three\\u000a dimensions of functioning: functional capacity,

Elizabeth Bromley; John S. Brekke

218

Risk functionals Dual properties  

E-print Network

Outline Risk functionals Dual properties A collection of risk functionals Risk and information Multiperiod models Acceptability functionals, risk capital functionals and risk deviation functionals: Primal and risk #12;Outline Risk functionals Dual properties A collection of risk functionals Risk and information

Pflug, Georg

219

Functional Communication and Executive Function in Aphasia  

ERIC Educational Resources Information Center

The purpose of this exploratory study was to investigate the relationship between functional communication and executive function ability in aphasia. Twenty-five participants with aphasia underwent examination with an extensive test battery including measures of functional communication, executive function ability, and language impairment.…

Fridriksson, Julius; Nettles, Caroline; Davis, Mary; Morrow, Leigh; Montgomery, Allen

2006-01-01

220

Network functional compression  

E-print Network

In this thesis, we consider different aspects of the functional compression problem. In functional compression, the computation of a function (or, some functions) of sources is desired at the receiver(s). The rate region ...

Feizi, Soheil (Feizi-Khankandi)

2010-01-01

221

Exploring Functional Mellin Transforms  

E-print Network

We define functional Mellin transforms within a scheme for functional integration proposed in [1]. Functional Mellin transforms can be used to define functional traces, logarithms, and determinants. The associated functional integrals are useful tools for probing function spaces in general and $C^\\ast$-algebras in particular. Several interesting aspects are explored.

J. LaChapelle

2015-01-08

222

Functional Mellin Transforms  

E-print Network

Functional integrals are defined in terms of locally compact topological groups and their associated Banach-valued Haar integrals. This approach generalizes the functional integral scheme of Cartier and DeWitt-Morette. The definition allows a construction of functional Mellin transforms. In turn, the functional Mellin transforms can be used to define functional traces, logarithms, and determinants. The associated functional integrals are useful tools for probing function spaces in general and $C^\\ast$-algebras in particular. Several interesting aspects are explored.

J. LaChapelle

2015-01-07

223

Functional Microorganisms for Functional Food Quality  

Microsoft Academic Search

Functional microorganisms and health benefits represent a binomial with great potential for fermented functional foods. The health benefits of fermented functional foods are expressed either directly through the interactions of ingested live microorganisms with the host (probiotic effect) or indirectly as the result of the ingestion of microbial metabolites synthesized during fermentation (biogenic effect). Since the importance of high viability

M. Gobbetti; R. Di Cagno; M. De Angelis

2010-01-01

224

Optimal Stimulus Amplitude for Vestibular Stochastic Stimulation to Improve Sensorimotor Function  

NASA Technical Reports Server (NTRS)

Sensorimotor changes such as postural and gait instabilities can affect the functional performance of astronauts when they transition across different gravity environments. We are developing a method, based on stochastic resonance (SR), to enhance information transfer by applying non-zero levels of external noise on the vestibular system (vestibular stochastic resonance, VSR). Our previous work has shown the advantageous effects of VSR in a balance task of standing on an unstable surface. This technique to improve detection of vestibular signals uses a stimulus delivery system that is wearable or portable and provides imperceptibly low levels of white noise-based binaural bipolar electrical stimulation of the vestibular system. The goal of this project is to determine optimal levels of stimulation for SR applications by using a defined vestibular threshold of motion detection. A series of experiments were carried out to determine a robust paradigm to identify a vestibular threshold that can then be used to recommend optimal stimulation levels for SR training applications customized to each crewmember. Customizing stimulus intensity can maximize treatment effects. The amplitude of stimulation to be used in the VSR application has varied across studies in the literature such as 60% of nociceptive stimulus thresholds. We compared subjects' perceptual threshold with that obtained from two measures of body sway. Each test session was 463s long and consisted of several 15s sinusoidal stimuli, at different current amplitudes (0-2 mA), interspersed with 20-20.5s periods of no stimulation. Subjects sat on a chair with their eyes closed and had to report their perception of motion through a joystick. A force plate underneath the chair recorded medio-lateral shear forces and roll moments. First we determined the percent time during stimulation periods for which perception of motion (activity above a pre-defined threshold) was reported using the joystick, and body sway (two standard deviation of the noise level in the baseline measurement) was detected by the sensors. The percentage time at each stimulation level for motion detection was normalized with respect to the largest value and a logistic regression curve fit was applied to these data. The threshold was defined at the 50% probability of motion detection. Comparison of threshold of motion detection obtained from joystick data versus body sway suggests that perceptual thresholds were significantly lower, and were not impacted by system noise. Further, in order to determine optimal stimulation amplitude to improve balance, two sets of experiments were carried out. In the first set of experiments, all subjects received the same level of stimuli and the intensity of optimal performance was projected back on subjects' vestibular threshold curve. In the second set of experiments, on different subjects, stimulation was administered from 20-400% of subjects' vestibular threshold obtained from joystick data. Preliminary results of our study show that, in general, using stimulation amplitudes at 40-60% of perceptual motion threshold improved balance performance significantly compared to control (no stimulation). The amplitude of vestibular stimulation that improved balance function was predominantly in the range of +/- 100 to +/- 400 micro A. We hypothesize that VSR stimulation will act synergistically with sensorimotor adaptability (SA) training to improve adaptability by increasing utilization of vestibular information and therefore will help us to optimize and personalize a SA countermeasure prescription. This combination will help to significantly reduce the number of days required to recover functional performance to preflight levels after long-duration spaceflight.

Goel, R.; Kofman, I.; DeDios, Y. E.; Jeevarajan, J.; Stepanyan, V.; Nair, M.; Congdon, S.; Fregia, M.; Cohen, H.; Bloomberg, J. J.; Mulavara, A. P.

2014-01-01

225

Design and Evaluation of a New Type of Knee Orthosis to Align the Mediolateral Angle of the Knee Joint with Osteoarthritis  

PubMed Central

Background. Osteoarthritis (OA) is a disease which influences the performance of the knee joint. Moreover, the force and moments applied on the joint increase in contrast to normal subjects. Various types of knee orthoses have been designed to solve the mentioned problems. However, there are other problems in terms of distal migration during walking and the alignment of the orthosis which cannot be changed following the use of brace. Therefore, the main aim of the research was to design an orthosis to solve the aforementioned problems. Method. A new type of knee orthosis was designed with a modular structure. Two patients with knee OA participated in this research project. The force applied on the foot, moment transmitted through the knee joint, and spatiotemporal gait parameters were measured by use of a motion analysis system. Results. The results of the research showed that the adduction moment applied on the knee joint decreased while subjects walked with the new knee orthosis (P-value < 0.05). Conclusion. The new design of the knee brace can be used as an effective treatment to decrease the loads applied on the knee joint and to improve the alignment whilst walking. PMID:22577565

Esrafilian, Amir; Karimi, Mohammad Taghi; Eshraghi, Arezoo

2012-01-01

226

Reduction of frontal-plane hip joint reaction force via medio-lateral foot center of pressure manipulation: a pilot study.  

PubMed

Footwear-generated biomechanical manipulation of lower-limb joints has been shown to influence lower-limb biomechanics. Numerous studies report the influence of such interventions on the knee, however little is known about the influence of these interventions on the hip. The present study analyzed kinetic and kinematic changes about the hip of 12 healthy young males who underwent biomechanical manipulation utilizing the APOS biomechanical device (APOS-Medical and Sports Technologies Ltd., Herzliya, Israel) allowing controlled foot center of pressure manipulation. Subjects underwent gait testing in four para-sagittal device configurations: Medial, lateral, neutral, and regular shoes. In the medial configuration, subjects demonstrated no change in step width (i.e., distance between right and left foot center of pressure), however inter-malleolar distance significantly increased. Likewise with the medial setting, greater hip abduction was recorded, while hip adduction moment and joint reaction force decreased significantly. We speculate that subjects adopt a modified gait pattern aimed to maintain constant base of support. As a result, hip abductor muscle moment arm increases and adduction moment and joint reaction force decreases. To the best of our knowledge this is the first study to show this relationship. These results contribute to the understanding of lower-limb biomechanics and warrant further investigation. PMID:25256253

Solomonow-Avnon, Deborah; Wolf, Alon; Herman, Amir; Rozen, Nimrod; Haim, Amir

2015-02-01

227

The development of vestibular system and related functions in mammals: impact of gravity  

PubMed Central

This chapter reviews the knowledge about the adaptation to Earth gravity during the development of mammals. The impact of early exposure to altered gravity is evaluated at the level of the functions related to the vestibular system, including postural control, homeostatic regulation, and spatial memory. The hypothesis of critical periods in the adaptation to gravity is discussed. Demonstrating a critical period requires removing the gravity stimulus during delimited time windows, what is impossible to do on Earth surface. The surgical destruction of the vestibular apparatus, and the use of mice strains with defective graviceptors have provided useful information on the consequences of missing gravity perception, and the possible compensatory mechanisms, but transitory suppression of the stimulus can only be operated during spatial flight. The rare studies on rat pups housed on board of space shuttle significantly contributed to this problem, but the use of hypergravity environment, produced by means of chronic centrifugation, is the only available tool when repeated experiments must be carried out on Earth. Even though hypergravity is sometimes considered as a mirror situation to microgravity, the two situations cannot be confused because a gravitational force is still present. The theoretical considerations that validate the paradigm of hypergravity to evaluate critical periods are discussed. The question of adaption of graviceptor is questioned from an evolutionary point of view. It is possible that graviception is hardwired, because life on Earth has evolved under the constant pressure of gravity. The rapid acquisition of motor programming by precocial mammals in minutes after birth is consistent with this hypothesis, but the slow development of motor skills in altricial species and the plasticity of vestibular perception in adults suggest that gravity experience is required for the tuning of graviceptors. The possible reasons for this dichotomy are discussed. PMID:24570658

Jamon, Marc

2013-01-01

228

Ocular-Motor Function and Information Processing: Implications for the Reading Process.  

ERIC Educational Resources Information Center

This paper discusses the dichotomy between continually moving eyes and the lack of blurred visual experience. A discontinuous model of visual perception is proposed, with the discontinuities being phase and temporally related to saccadic eye movements. It is further proposed that deviant duration and angular velocity characteristics of saccades in…

Leisman, Gerald; Schwartz, Joddy

229

Functional differences and complementation between dendritic cells and macrophages in T-cell activation.  

PubMed Central

Functional differences and cell collaboration between murine lymphoid dendritic cells (DC) and macrophages (M phi) in antigen presentation for T-cell activation were analysed with splenic DC and M phi, culture-derived bone-marrow (BM)-M phi, and DC-like and M phi-like cell lines. DC were the best stimulators of allogeneic mixed leucocyte reaction (MLR), but splenic M phi and small activated BM-M phi were almost as effective. In contrast to MLR stimulation, small activated BM-M phi were the most effective antigen-presenting cells (APC) for the presentation of whole Corynebacterium parvum (CP) organisms, possibly by virtue of their phagocytic and lysosomal functions, which could be particularly important for processing particulate antigens. Large activated BM-M phi were ineffective in stimulating MLR and CP-specific T-cell proliferation. The functional differences between BM-M phi subsets could not be explained by failure to express surface Ia or to take up antigen. Non-phagocytic APC, such as DC and the DC-like line P388AD.4, had low presenting activity for CP and were much less effective at presenting glutaraldehyde-fixed CP than M phi. This suggests that DC are dependent on the shedding of soluble antigen (reduced by glutaraldehyde fixation) from the bacteria, and they may also be less efficient than M phi at processing the fixed bacteria. The Ia- M phi-like line. P388D1, was devoid of APC activity, but could greatly enhance P388AD.4-induced T-cell proliferation to whole bacterial organisms. Similarly, co-culture of splenic DC and M phi produced very pronounced synergistic effects in proliferative responses to CP and keyhole limpet haemocyanin. The function of M phi n this partnership was sensitive to chloroquine and could not be replaced by M phi culture fluids or recombinant interleukin-1. Thus, M phi may contribute processed antigen in a form more suitable for presentation by DC. These results provide a rationale for the functional dichotomy between DC and M phi. PMID:2956179

Guidos, C; Sinha, A A; Lee, K C

1987-01-01

230

Functional Heads and Interpretation   

E-print Network

This thesis examines the effect that functional heads have on the interpretation of arguments.It focuses on the functional head Agr, which is implicated in predicate-argument agreement relations; the import that other functional heads have...

Adger, David

231

Childhood Functional GI Disorders  

MedlinePLUS

... Merchandise Take Action Contact Us Donate Childhood Functional GI Disorders A functional disorder refers to a disorder ... regurgitation, heartburn, or food refusal. Examples of functional GI disorders in kids and teens include: Infant regurgitation ...

232

Congenital platelet function defects  

MedlinePLUS

Platelet storage pool disorder; Glanzmann's thrombasthenia; Bernard-Soulier syndrome; Platelet function defects - congenital ... Congenital platelet function defects are bleeding disorders that cause ... function, even though there are normal platelet counts. ...

233

Calculator Function Approximation.  

ERIC Educational Resources Information Center

The general algorithm used in most hand calculators to approximate elementary functions is discussed. Comments on tabular function values and on computer function evaluation are given first; then the CORDIC (Coordinate Rotation Digital Computer) scheme is described. (MNS)

Schelin, Charles W.

1983-01-01

234

What Function is This?  

ERIC Educational Resources Information Center

Presents several types of functions which fit a given set of data and create opportunities for classroom discussion comparing different kinds of functions and identifying some of the potential hazards associated with extrapolation from best-fit functions. (DDR)

Dobbs, David E.; Peterson, John C.

1997-01-01

235

Functional Notations and Terminology  

NSDL National Science Digital Library

This mathematics tutorial gives users an introduction to functions, functional notation and terminology. The site explains how a function is defined, and the correct way to read and write functional notation. Resources for addition, subtraction and multiplication of functions are also provided on this site. The â??Examples of Functionsâ? section is very useful for understanding the applications of functional theory learned in the previous sections.

Bogomolny, Alexander

236

Wave-function functionals for the density  

SciTech Connect

We extend the idea of the constrained-search variational method for the construction of wave-function functionals {psi}[{chi}] of functions {chi}. The search is constrained to those functions {chi} such that {psi}[{chi}] reproduces the density {rho}(r) while simultaneously leading to an upper bound to the energy. The functionals are thereby normalized and automatically satisfy the electron-nucleus coalescence condition. The functionals {psi}[{chi}] are also constructed to satisfy the electron-electron coalescence condition. The method is applied to the ground state of the helium atom to construct functionals {psi}[{chi}] that reproduce the density as given by the Kinoshita correlated wave function. The expectation of single-particle operators W={Sigma}{sub i}r{sub i}{sup n}, n=-2,-1,1,2, W={Sigma}{sub i}{delta}(r{sub i}) are exact, as must be the case. The expectations of the kinetic energy operator W=-(1/2){Sigma}{sub i}{nabla}{sub i}{sup 2}, the two-particle operators W={Sigma}{sub n}u{sup n}, n=-2,-1,1,2, where u=|r{sub i}-r{sub j}|, and the energy are accurate. We note that the construction of such functionals {psi}[{chi}] is an application of the Levy-Lieb constrained-search definition of density functional theory. It is thereby possible to rigorously determine which functional {psi}[{chi}] is closer to the true wave function.

Slamet, Marlina; Pan Xiaoyin; Sahni, Viraht [Sacred Heart University, Fairfield, Connecticut 06825 (United States); Faculty of Science, Ningbo University, 315211 Ningbo (China); Brooklyn College and The Graduate School of the City University of New York, New York, New York 10016 (United States)

2011-11-15

237

More Complicated Functions: Introduction to Linear Functions  

NSDL National Science Digital Library

This lesson is designed to introduce students to the idea of functions composed of two operations, with specific attention to linear functions and their representations as rules and data tables. The lesson also introduces the concepts surrounding independent and dependent variables. This lesson provides links to discussions and activities related to multi-step linear functions as well as suggested ways to integrate them into the lesson. Finally, the lesson provides links to other lessons designed as follow-up to multi-step functions.

2011-01-20

238

Spectral functions from the functional renormalization group  

NASA Astrophysics Data System (ADS)

We present a viable method to obtain real-time quantities such as spectral functions or transport coefficients at finite temperature and density within a non-perturbative functional renormalization group approach. Our method is based on a thermodynamically consistent truncation of the flow equations for 2-point functions with analytically continued frequency components in the originally Euclidean external momenta. We demonstrate its feasibility by calculating the mesonic spectral functions in the quark-meson model at different temperatures and quark chemical potentials, in particular around the critical endpoint in the phase diagram of the model.

Tripolt, Ralf-Arno; Strodthoff, Nils; von Smekal, Lorenz; Wambach, Jochen

2014-11-01

239

Green's functions Lucia Reining  

E-print Network

Green's functions Lucia Reining Laboratoire des Solides Irradi´es Ecole Polytechnique, Palaiseau - France European Theoretical Spectroscopy Facility (ETSF) Belfast, 27.6.2007 Green's functions Lucia mechanics 6 The one-particle Green's function in detail 7 Conclusions Green's functions Lucia Reining #12

Botti, Silvana

240

Introduction to Functions  

NSDL National Science Digital Library

This lesson is designed to introduce students to functions as rules and independent and dependent variables. The lesson provides links to discussions and activities that motivate the idea of a function as a machine as well as proper terminology when discussing functions. Finally, the lesson provides links to follow-up lessons designed for use in succession to the introduction of functions.

2011-01-19

241

Differential Item Functioning vs Differential Test Functioning.  

ERIC Educational Resources Information Center

A problem that arises when a differential item functioning (DIF) study is done with samples of examinees differing in ability is examined. A test may function differently when the populations from which the items are calibrated are not of equal ability. Since the lower ability examinees get many difficult items incorrect, the spread (standard…

Bergstrom, Betty A.; And Others

242

Functional bowel disorders and functional abdominal pain  

Microsoft Academic Search

The Rome diagnostic criteria for the functional bowel disorders and functional abdominal pain are used widely in research and practice. A committee consensus approach, including criticism from multinational expert reviewers, was used to revise the diagnostic criteria and update diagnosis and treatment recommendations, based on research results. The terminology was clarified and the diagnostic criteria and management recommendations were revised.

W G Thompson; G F Longstreth; D A Drossman; K W Heaton; E J Irvine; S A Müller-Lissner

1999-01-01

243

Functional Power Series  

E-print Network

This work introduces a new functional series for expanding an analytic function in terms of an arbitrary analytic function. It is generally applicable and straightforward to use. It is also suitable for approximating the behavior of a function with a few terms. A new expression is presented for the composite function's n'th derivative. The inverse-composite method is handled in this work also.

Henrik Stenlund

2012-04-24

244

Sampling functions for geophysics  

NASA Technical Reports Server (NTRS)

A set of spherical sampling functions is defined such that they are related to spherical-harmonic functions in the same way that the sampling functions of information theory are related to sine and cosine functions. An orderly distribution of (N + 1) squared sampling points on a sphere is given, for which the (N + 1) squared spherical sampling functions span the same linear manifold as do the spherical-harmonic functions through degree N. The transformations between the spherical sampling functions and the spherical-harmonic functions are given by recurrence relations. The spherical sampling functions of two arguments are extended to three arguments and to nonspherical reference surfaces. Typical applications of this formalism to geophysical topics are sketched.

Giacaglia, G. E. O.; Lunquist, C. A.

1972-01-01

245

Linear Function Machine  

NSDL National Science Digital Library

In this activity, students plug values into a function to see what the output is for that function. Then based on that information, they have to guess the coefficient and constant for a linear function. This activity allows students to explore linear functions and what input values are useful to figuring out the linear function performed by the function machine. This activity includes supplemental materials, including background information about the topics covered, a description of how to use the application, and exploration questions for use with the java applet.

2010-01-01

246

Functionalized boron nitride nanotubes  

DOEpatents

A plasma treatment has been used to modify the surface of BNNTs. In one example, the surface of the BNNT has been modified using ammonia plasma to include amine functional groups. Amine functionalization allows BNNTs to be soluble in chloroform, which had not been possible previously. Further functionalization of amine-functionalized BNNTs with thiol-terminated organic molecules has also been demonstrated. Gold nanoparticles have been self-assembled at the surface of both amine- and thiol-functionalized boron nitride Nanotubes (BNNTs) in solution. This approach constitutes a basis for the preparation of highly functionalized BNNTs and for their utilization as nanoscale templates for assembly and integration with other nanoscale materials.

Sainsbury, Toby; Ikuno, Takashi; Zettl, Alexander K

2014-04-22

247

Function of Transferrin  

Microsoft Academic Search

Recent work on the structure and function of transferrin indicates that it is not only an inert carrier of iron but that it has a complex function in the absorption and distribution of iron in the body.

J. Fletcher; E. R. Huehns

1968-01-01

248

Pulmonary Function Tests  

MedlinePLUS

... like asthma, chronic obstructive lung disease (COPD), or cystic fibrosis on lung function. ? Identify early changes in lung function that might show a need for a change in treatment. ? Detect narrowing in the airways. ? Decide if a ...

249

Linear Function Machine  

NSDL National Science Digital Library

This activity allows the user to explore simple linear functions. This Java applet requires a Java-capable browser. If you don't see the applet Java may not be functional in your browser or on your machine.

The Shodor Education Foundation, Inc.

2007-12-12

250

Hypertrapezoidal fuzzy membership functions  

E-print Network

The authors present a method for representing N-dimensional fuzzy membership functions. The proposed method is a generalization of the one-dimensional trapezoidal membership function commonly used in fuzzy systems. The issue of correlation between...

Painter, John H.; Kelly, W. E. III

1996-09-08

251

Positive Linear Function Machine  

NSDL National Science Digital Library

Students investigate linear functions with positive slopes by trying to guess the slope and intercept from inputs and outputs. Positive Linear Function Machine is one of the Interactivate assessment explorers.

252

[Children visual functions development].  

PubMed

Development of vision mainly takes place during the first year of life. Visual function isn't restricted to the measurement of visual acuity, but includes functions of environment exploration, relative appreciation of objects, control of body position and movements organization. Visual function comprises sensorial, oculomotor and cognitive elements. Each alteration in visual experience exposes to amblyopia inside the period of sensitivity of visual function. PMID:18326433

Speeg-Schatz, Claude

2007-11-30

253

Monotone Boolean functions  

NASA Astrophysics Data System (ADS)

Monotone Boolean functions are an important object in discrete mathematics and mathematical cybernetics. Topics related to these functions have been actively studied for several decades. Many results have been obtained, and many papers published. However, until now there has been no sufficiently complete monograph or survey of results of investigations concerning monotone Boolean functions. The object of this survey is to present the main results on monotone Boolean functions obtained during the last 50 years.

Korshunov, A. D.

2003-10-01

254

Functional Task Test (FTT)  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the Functional Task Test (FTT), an interdisciplinary testing regimen that has been developed to evaluate astronaut postflight functional performance and related physiological changes. The objectives of the project are: (1) to develop a set of functional tasks that represent critical mission tasks for the Constellation Program, (2) determine the ability to perform these tasks after space flight, (3) Identify the key physiological factors that contribute to functional decrements and (4) Use this information to develop targeted countermeasures.

Bloomberg, Jacob J.; Mulavara, Ajitkumar; Peters, Brian T.; Rescheke, Millard F.; Wood, Scott; Lawrence, Emily; Koffman, Igor; Ploutz-Snyder, Lori; Spiering, Barry A.; Feeback, Daniel L.; Platts, Steven H.; Stenger, Michael B.; Lee, Stuart M.C.; Arzeno, Natalia; Feiveson, Alan H.; Ryder, Jeffrey; Garcia, Yamil; Guilliams, Mark E.

2009-01-01

255

Functional polymer microspheres  

Microsoft Academic Search

Functional particles are prepared directly by heterogeneous polymerization, e.g. emulsion polymerization and dispersion polymerization. Modification of existing particles is another method to prepare functional particles. The features of nano- or microparticles such as large specific surface area, high mobility, easy recovery from the dispersion and reversible dispersibility, etc., are utilized for the exhibition of functions. Medical and biochemical applications of

Haruma Kawaguchi

2000-01-01

256

Fast Software Encryption Functions  

Microsoft Academic Search

Encryption hardware is not available on most computer systems in use today. Despite thisfact, there is no well accepted encryption function designed for software implementation -- instead, hardware designs are emulated in software and the resulting performance loss istolerated. The obvious solution is to design an encryption function for implementation insoftware. Such an encryption function is presented here -- on

Ralph C. Merkle

1990-01-01

257

Graphs and Functions  

NSDL National Science Digital Library

This lesson is designed to introduce students to plotting points and graphing functions in the Cartesian coordinate system. The lesson provides links to discussions and activities that transition from functions as rules to the graphs of those functions. Finally, the lesson provides links to follow-up lessons designed for use in succession to an introduction to graphing.

2010-01-01

258

Plant functional genomics  

Microsoft Academic Search

Functional genome analysis of plants has entered the high-throughput stage. The complete genome information from key species such as Arabidopsis thaliana and rice is now available and will further boost the application of a range of new technologies to functional plant gene analysis. To broadly assign functions to unknown genes, different fast and multiparallel approaches are currently used and developed.

Hauke Holtorf; Marie-Christine Guitton; Ralf Reski

2002-01-01

259

Pediatric functional gastrointestinal disorders  

Technology Transfer Automated Retrieval System (TEKTRAN)

Functional gastrointestinal disorders continue to be a prevalent set of conditions faced by the healthcare team and have a significant emotional and economic impact. In this review, the authors highlight some of the common functional disorders seen in pediatric patients (functional dyspepsia, irrita...

260

Generating Functions Introduction  

E-print Network

CHAPTER 10 Ordinary Generating Functions Introduction We'll begin this chapter by introducing the notion of ordinary generating functions and discussing the basic techniques for manipulating them must master these basic ideas before reading further. In Section 2, we apply generating functions

Gould, Ron

261

An Exceptional Exponential Function  

ERIC Educational Resources Information Center

We show that there is a link between a standard calculus problem of finding the best view of a painting and special tangent lines to the graphs of exponential functions. Surprisingly, the exponential function with the "best view" is not the one with the base "e." A similar link is established for families of functions obtained by composing…

Curgus, Branko

2006-01-01

262

Differentially Transcendental Functions  

E-print Network

The aim of this paper is to exhibit a method for proving that certain analytic functions are not solutions of algebraic differential equations. The method is based on model-theoretic properties of differential fields and properties of certain known transcendental differential functions, as of $\\Gamma(x)$. Furthermore, it also determines differential transcendency of solution of some functional equations.

Zarko Mijajlovic; Branko Malesevic

2008-04-15

263

Two Functions of Language  

ERIC Educational Resources Information Center

Author advocates the view that meaning is necessarily dependent upon the communicative function of language and examines the objections, particularly those of Noam Chomsky, to this view. Argues that while Chomsky disagrees with the idea that communication is the essential function of language, he implicitly agrees that it has a function

Feldman, Carol Fleisher

1977-01-01

264

Lesson 30: Exponential Functions  

NSDL National Science Digital Library

Beginning with a formal definition of an exponential function, the lesson then compares the graphs of increasing and decreasing exponential functions. A comparison between exponential and power functions follows, which leads to methods for determining the h value in the power function h(x) = kx^p and the value of the base b in the exponential function f(x) = ab^x. A procedure for solving exponential equations is presented before a population application problem is solved. The lesson concludes with a discussion about using graphs to find approximate solutions to exponential equations.

2011-01-01

265

Frequent disruption of chromodomain helicase DNA-binding protein 8 (CHD8) and functionally associated chromatin regulators in prostate cancer.  

PubMed

Abnormal expression and function of chromatin regulators results in the altered chromatin structure seen in cancer. The chromatin regulator CTCF, its cofactor CHD8, and antagonistic paralogue BORIS have wide-ranging effects on gene regulation. Their concurrent expression and regulation was examined in benign, localized, and metastatic prostate cancer (PCa) arrays with extended follow-up using an automated quantitative imaging system, VECTRA. Epithelial staining was quantified and compared against a range of clinicopathologic variables. CHD8 expression was decreased in HGPIN, localized, and metastatic PCa compared to benign (P < .001). CHD8 promoter hypermethylation, assessed by Quantitative Pyrosequencing, occurred in over 45% of primary cancers in this population as well as the TGCA database. Treatment of cell lines with the demethylating agent 5-Aza-2'-deoxycytidine reinduced expression. An interesting dichotomy for CHD8 was observed within primary cancers, with higher nuclear protein expression associated with adverse clinical outcomes including extracapsular extension (P = .007), presence of metastases (P = .025) and worse PSA-recurrence free survival (P = .048). CHD8 outperformed Gleason score and predicted biochemical failure within intermediate grade prostate cancers. The BORIS/CTCF expression ratio increased in localized (P = .03) and metastatic PCa (P = .006) and was associated with higher Gleason score (P = .02), increased tumor volume (P = .02) and positive margins (P = .04). Per cell heterogeneity of expression revealed all protein expression to be more heterogeneous in cancerous tissue (both P < .001), especially high grade (P < .01). In the first detailed analysis in cancer, a marked loss of CHD8 expression and increased BORIS/CTCF ratio indicate frequent disruption of CTCF and its effector genes in PCa. PMID:25499215

Damaschke, Nathan A; Yang, Bing; Blute, Michael L; Lin, Chee Paul; Huang, Wei; Jarrard, David F

2014-12-01

266

Frequent Disruption of Chromodomain Helicase DNA-Binding Protein 8 (CHD8) and Functionally Associated Chromatin Regulators in Prostate Cancer  

PubMed Central

Abnormal expression and function of chromatin regulators results in the altered chromatin structure seen in cancer. The chromatin regulator CTCF, its cofactor CHD8, and antagonistic paralogue BORIS have wide-ranging effects on gene regulation. Their concurrent expression and regulation was examined in benign, localized, and metastatic prostate cancer (PCa) arrays with extended follow-up using an automated quantitative imaging system, VECTRA. Epithelial staining was quantified and compared against a range of clinicopathologic variables. CHD8 expression was decreased in HGPIN, localized, and metastatic PCa compared to benign (P < .001). CHD8 promoter hypermethylation, assessed by Quantitative Pyrosequencing, occurred in over 45% of primary cancers in this population as well as the TGCA database. Treatment of cell lines with the demethylating agent 5-Aza-2?-deoxycytidine reinduced expression. An interesting dichotomy for CHD8 was observed within primary cancers, with higher nuclear protein expression associated with adverse clinical outcomes including extracapsular extension (P = .007), presence of metastases (P = .025) and worse PSA-recurrence free survival (P = .048). CHD8 outperformed Gleason score and predicted biochemical failure within intermediate grade prostate cancers. The BORIS/CTCF expression ratio increased in localized (P = .03) and metastatic PCa (P = .006) and was associated with higher Gleason score (P = .02), increased tumor volume (P = .02) and positive margins (P = .04). Per cell heterogeneity of expression revealed all protein expression to be more heterogeneous in cancerous tissue (both P < .001), especially high grade (P < .01). In the first detailed analysis in cancer, a marked loss of CHD8 expression and increased BORIS/CTCF ratio indicate frequent disruption of CTCF and its effector genes in PCa. PMID:25499215

Damaschke, Nathan A.; Yang, Bing; Blute, Michael L.; Lin, Chee Paul; Huang, Wei; Jarrard, David F.

2014-01-01

267

MicroRNA Sequence Variation Potentially Contributes to Within-Species Functional Divergence in the Nematode Caenorhabditis briggsae  

PubMed Central

Mounting evidence points to differences in gene regulation as a major source of phenotypic variation. MicroRNA-mediated post-transcriptional regulation has emerged recently as a key factor controlling gene activity during development. MicroRNA genes are abundant in genomes, acting as managers of gene expression by directing translational repression. Thus, understanding the role of microRNA sequence variation within populations is essential for fully dissecting the origin and maintenance of phenotypic diversity in nature. In this study, we investigate allelic variation at microRNA loci in the nematode Caenorhabditis briggsae, a close relative of C. elegans. Phylogeographic structure in C. briggsae partitions most strains from around the globe into a “temperate” or a “tropical” clade, with a few strains having divergent, geographically restricted genotypes. Remarkably, strains that follow this latitudinal dichotomy also differ in temperature-associated fitness. With this phylogeographic pattern in mind, we examined polymorphisms in 18 miRNAs in a global sample of C. briggsae isolates and tested whether newly isolated strains conform to this phylogeography. Surprisingly, nucleotide diversity is relatively high in this class of gene that generally experiences strong purifying selection. In particular, we find that miRNAs in C. briggsae are substantially more polymorphic than in Arabidopsis thaliana, despite similar background levels of neutral site diversity between the two species. We find that some mutations suggest functional divergence on the basis of requirements for target site recognition and computational prediction of the effects of the polymorphisms on RNA folding. These findings demonstrate the potential for miRNA polymorphisms to contribute to phenotypic variation within a species. Sequences were deposited in GenBank under accession nos. JN251323–JN251744. PMID:21890738

Jovelin, Richard; Cutter, Asher D.

2011-01-01

268

Zeta Functional Analysis  

E-print Network

We intimate deeper connections between the Riemann zeta and gamma functions than often reported and further derive a new formula for expressing the value of $\\zeta(2n+1)$ in terms of zeta at other fractional points. This paper also establishes and presents new expository notes and perspectives on zeta function theory and functional analysis. In addition, a new fundamental result, in form of a new function called omega $\\Omega(s)$, is introduced to analytic number theory for the first time. This new function together with some of its most fundamental properties and other related identities are here disclosed and presented as a new approach to the analysis of sums of generalised harmonic series, related alternating series and polygamma functions associated with Riemann zeta function.

Michael A. Idowu

2014-10-15

269

On genetic map functions  

SciTech Connect

Various genetic map functions have been proposed to infer the unobservable genetic distance between two loci from the observable recombination fraction between them. Some map functions were found to fit data better than others. When there are more than three markers, multilocus recombination probabilities cannot be uniquely determined by the defining property of map functions, and different methods have been proposed to permit the use of map functions to analyze multilocus data. If for a given map function, there is a probability model for recombination that can give rise to it, then joint recombination probabilities can be deduced from this model. This provides another way to use map functions in multilocus analysis. In this paper we show that stationary renewal processes give rise to most of the map functions in the literature. Furthermore, we show that the interevent distributions of these renewal processes can all be approximated quite well by gamma distributions. 43 refs., 4 figs.

Zhao, Hongyu [Univ. of California, Los Angeles, CA (United States); Speed, T.P. [Univ. of California, Berkeley, CA (United States)

1996-04-01

270

Functional Explanation and the Function of Explanation  

ERIC Educational Resources Information Center

Teleological explanations (TEs) account for the existence or properties of an entity in terms of a function: we have hearts because they pump blood, and telephones for communication. While many teleological explanations seem appropriate, others are clearly not warranted--for example, that rain exists for plants to grow. Five experiments explore…

Lombrozo, Tania; Carey, Susan

2006-01-01

271

Function photonic crystals  

NASA Astrophysics Data System (ADS)

In this paper, we present a new kind of function photonic crystals (PCs), whose refractive index is a function of space position. Conventional PCs structure grows from two materials, A and B, with different dielectric constants ?A and ?B. Based on Fermat principle, we give the motion equations of light in one-dimensional, two-dimensional and three-dimensional function photonic crystals. For one-dimensional function photonic crystals, we give the dispersion relation, band gap structure and transmissivity, and compare them with conventional photonic crystals, and we find the following: (1) For the vertical and non-vertical incidence light of function photonic crystals, there are band gap structures, and for only the vertical incidence light, the conventional PCs have band gap structures. (2) By choosing various refractive index distribution functions n( z), we can obtain more wider or more narrower band gap structure than conventional photonic crystals.

Wu, Xiang-Yao; Zhang, Bai-Jun; Yang, Jing-Hai; Liu, Xiao-Jing; Ba, Nuo; Wu, Yi-Heng; Wang, Qing-Cai

2011-07-01

272

Selectively localized Wannier functions  

NASA Astrophysics Data System (ADS)

Since the seminal work of Marzari and Vanderbilt, maximally localized Wannier functions have become widely used as a real-space representation of the electronic structure of periodic materials. In this paper we introduce selectively localized Wannier functions which extend the method of Marzari and Vanderbilt in two important ways. First, our method allows us to focus on localizing a subset of orbitals of interest. Second, our method allows us to fix centers of these orbitals, and ensure the preservation of the point-group symmetry. These characteristics are important when Wannier functions are used in methodologies that go beyond density functional theory by treating a local subspace of the Hamiltonian more effectively. Application of our method to GaAs, SrMnO3, and Co demonstrates that selectively localized Wannier functions can offer improvements over the maximally localized Wannier function technique.

Wang, Runzhi; Lazar, Emanuel A.; Park, Hyowon; Millis, Andrew J.; Marianetti, Chris A.

2014-10-01

273

Balance Function Disorders  

NASA Technical Reports Server (NTRS)

Researchers at the Balance Function Laboratory and Clinic at the Minneapolis (MN) Neuroscience Institute on the Abbot Northwestern Hospital Campus are using a rotational chair (technically a "sinusoidal harmonic acceleration system") originally developed by NASA to investigate vestibular (inner ear) function in weightlessness to diagnose and treat patients with balance function disorders. Manufactured by ICS Medical Corporation, Schaumberg, IL, the chair system turns a patient and monitors his or her responses to rotational stimulation.

1991-01-01

274

Hormonally functional ovarian neoplasms  

Microsoft Academic Search

Hormonally functional ovarian neoplasms are those tumors that secrete one or more hormones that are clinically manifested\\u000a in the patient. The hormone production may have implications for the diagnosis, management, or treatment of the patient. Hormonally\\u000a functional ovarian neoplasms include tumors that belong to various histologic categories and produce a variety of hormonal\\u000a effects. Functional ovarian tumors most commonly produce

Lawrence M. Roth; Steven D. Billings

2000-01-01

275

The visibility function revisited  

Microsoft Academic Search

The visibility function of a compact setS E\\u000a\\u000ad\\u000a assigns to eachx S the Lebesgue outer measure of its star inS. This function was introduced by G. Beer in 1972. In 1991, A. Forte Cunto characterized the points of discontinuity of the visibility function in the boundary of a planar Jordan domain. The basic intention of this paper is to

Ana Forte Cunto; María Piacquadio Losada; Fausto A. Toranzos

1999-01-01

276

Quadratic Functions: Workshop 4  

NSDL National Science Digital Library

Lesson 1 of two lessons requires students to explore quadratic functions by examining the family of functions described by y = a (x - h)squared+ k. In Lesson 2 students explore quadratic functions by using a motion detector known as a Calculator Based Ranger (CBR) to examine the heights of the different bounces of a ball. Students will represent each bounce with a quadratic function of the form y = a (x - h)squared + k. Background information, resources, references and videos of the lessons are included. Students work in teams of four.

Annenberg Media, Insights into Algebra, Teaching for Learning

2009-12-23

277

Graphing and Functions  

NSDL National Science Digital Library

Graphing points, lines, and writing equations from tables or graphs. Functions. Read carefully about plotting points at coolmath4kids. Coolmath Plotting Points Play the game twice or more if you aren't getting most of them right. A score of over 7000 would be good. Coordinate plane quadrants and ordered pairs. Read about Time/distance Time and distance graphs and then Time/speed. Time and speed graphs Read about and practice functions. Intro to functions Function crunchersDomain and range. Domain and Range Then vertical line test. Vertical Line Test ...

Mrs. Arnold

2011-11-17

278

Asymmetric synthesis of densely functionalized medium-ring carbocycles and lactones through modular assembly and ring-closing metathesis of sulfoximine-substituted trienes and dienynes.  

PubMed

An asymmetric synthesis of densely functionalized 7-11-membered carbocycles and 9-11-membered lactones has been developed. Its key steps are a modular assembly of sulfoximine-substituted C- and O-tethered trienes and C-tethered dienynes and their Ru-catalyzed ring-closing diene and enyne metathesis (RCDEM and RCEYM). The synthesis of the C-tethered trienes and dienynes includes the following steps: 1) hydroxyalkylation of enantiomerically pure titanated allylic sulfoximines with unsaturated aldehydes, 2) ?-lithiation of alkenylsulfoximines, 3) alkylation, hydroxy-alkylation, formylation, and acylation of ?-lithioalkenylsulfoximines, and 4) addition of Grignard reagents to ?-formyl(acyl)alkenylsulfoximines. The sulfoximine group provided for high asymmetric induction in steps 1) and 4). RCDEM of the sulfoximine-substituted trienes with the second-generation Ru catalyst stereoselectively afforded the corresponding functionalized 7-11-membered carbocyles. RCDEM of diastereomeric silyloxy-substituted 1,6,12-trienes revealed an interesting difference in reactivity. While the (R)-diastereomer gave the 11-membered carbocyle, the (S)-diastereomer delivered in a cascade of cross metathesis and RCDEM 22-membered macrocycles. RCDEM of cyclic trienes furnished bicyclic carbocycles with a bicyclo[7.4.0]tridecane and bicyclo[9.4.0]pentadecane skeleton. Selective transformations of the sulfoximine- and bissilyloxy-substituted carbocycles were performed including deprotection, cross-coupling reaction and reduction of the sulfoximine moiety. Esterification of a sulfoximine-substituted homoallylic alcohol with unsaturated carboxylic acids gave the O-tethered trienes, RCDEM of which yielded the sulfoximine-substituted 9-11-membered lactones. RCEYM of a sulfoximine-substituted 1,7-dien-10-yne showed an unprecedented dichotomy in ring formation depending on the Ru catalyst. While the second-generation Ru catalyst gave the 9-membered exo 1,3-dienyl carbocycle, the first-generation Ru catalyst furnished a truncated 9-membered 1,3-dieny carbocycle having one CH(2) unit less than the dienyne. PMID:22345000

Lejkowski, Michal; Banerjee, Prabal; Schüller, Sabine; Münch, Alexander; Runsink, Jan; Vermeeren, Cornelia; Gais, Hans-Joachim

2012-03-19

279

Continuity of Piecewise Functions  

NSDL National Science Digital Library

Students in calculus need to be proficient in working with functions in a variety of ways: graphical, numerical, analytic, or verbal, and to understand connections among these representations. This demo provides a set of visualizations designed to help students better understand what it means for a piecewise function to be continuous at a particular domain value.

Roberts, Lila F.

2004-08-14

280

Linear Functions Matching Activity  

NSDL National Science Digital Library

This activity is designed to help students connect various representations (verbal, tabular, graphical) of linear functions. The activity is designed to be completed in groups of 2. This would be an appropriate review activity towards the end of the unit on graphing linear functions.

2011-01-01

281

Brain Hemispheric Functioning.  

ERIC Educational Resources Information Center

Four articles consider brain hemisphere functioning of gifted students as it relates to gifted programs; alternation of education methodologies; spatial ability as an element of intellectual gifted functioning; and the interaction between hemisphere specialization, imagery, creative imagination, and sex differentiation. (SB)

Roeper Review, 1981

1981-01-01

282

Functional Generalized Additive Models.  

PubMed

We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online. PMID:24729671

McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

2014-01-01

283

Noncommutative symmetric functions  

Microsoft Academic Search

This paper presents a noncommutative theory of symmetric functions, based on the notion of quasi-determinant. We begin with a formal theory, corresponding to the case of symmetric functions in an infinite number of independent variables. This allows us to endow the resulting algebra with a Hopf structure, which leads to a new method for computing in descent algebras. It also

Israel Gelfand; D. Krob; Alain Lascoux; B. Leclerc; V. S. Retakh; J.-Y. Thibon

1994-01-01

284

Functional Generalized Additive Models  

PubMed Central

We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online. PMID:24729671

McLean, Mathew W.; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

2014-01-01

285

Human Functional Brain Imaging  

E-print Network

Human Functional Brain Imaging 1990­2009 September 2011 Portfolio Review Summary Brain Imaging #12 Dale ­ one of our first Trustees. Understanding the brain remains one of our key strategic aims today three-fold: · to identify the key landmarks and influences on the human functional brain imaging

Rambaut, Andrew

286

Program Computes Thermodynamic Functions  

NASA Technical Reports Server (NTRS)

PAC91 is latest in PAC (Properties and Coefficients) series. Two principal features are to provide means of (1) generating theoretical thermodynamic functions from molecular constants and (2) least-squares fitting of these functions to empirical equations. PAC91 written in FORTRAN 77 to be machine-independent.

Mcbride, Bonnie J.; Gordon, Sanford

1994-01-01

287

Double Function Machine  

NSDL National Science Digital Library

This Flash applet allows the user to explore the concept of a function using an input-output machine with two operations and options to set and hide or reveal all operations and numbers. A notepad is available for recording inputs and outputs, and a loop function takes the current output as the next input.

Dan Bunker

2010-01-01

288

Functions of Living Things  

NSDL National Science Digital Library

The purpose of this assessment probe is to elicit students' ideas about the functions carried out by plants and animals for maintaining life. The task specifically seeks to find out if students recognize that plants and animals share several common life functions, even though they are seemingly very different organisms.

Francis Eberle

2005-01-01

289

Functional foods innovations  

Technology Transfer Automated Retrieval System (TEKTRAN)

The aim of the Dairy and Functional Foods Research Unit (DFFRU), ERRC, ARS, USDA, is to improve human health and well being by developing functional food and consumer products that utilize milk and fruit and vegetable processing residues of specialty crops. Major research approaches involve: biotec...

290

Elementary Functions and Transformations  

E-print Network

and constants we build functions that model cost, revenue and profit. The graphs of cost revenue and profit? · Using the square root function we can find break even points and find intervals of profitability. · Using the absolute value we can measure sizes of changes in cost, revenue and profit. 72 Vertical

Fuller, Terry

291

Weakly ?-continuous functions  

Microsoft Academic Search

It is the objective of this paper to introduce a new class of generalizations of continuous functions via ‚-open sets called weakly ‚- continuous functions. Moreover, we study some of its fundamental prop- erties. It turns out that weak ‚-continuity is weaker than ‚-continuity (1).

Takashi Noiri; S. Jafari; M. Caldas

1987-01-01

292

Modeling Protein Domain Function  

ERIC Educational Resources Information Center

This simple but effective laboratory exercise helps students understand the concept of protein domain function. They use foam beads, Styrofoam craft balls, and pipe cleaners to explore how domains within protein active sites interact to form a functional protein. The activity allows students to gain content mastery and an understanding of the…

Baker, William P.; Jones, Carleton "Buck"; Hull, Elizabeth

2007-01-01

293

Contest success functions  

Microsoft Academic Search

Tournaments, conflict, and rent-seeking have been modelled as contests in which participants exert effort to increase their probability of winning a prize. A Contest Success Function (CSF) provides each player's probability of winning as a function of all players' efforts. In this paper the additive CSF employed in most contests is axiomatized, with an independence from irrelevant alternatives property as

Stergios Skaperdas

1996-01-01

294

Functional performance of pyrovalves  

NASA Technical Reports Server (NTRS)

Following several flight and ground test failures of spacecraft systems using single-shot, 'normally closed' pyrotechnically actuated valves (pyrovalves), a Government/Industry cooperative program was initiated to assess the functional performance of five qualified designs. The goal of the program was to provide information on functional performance of pyrovalves to allow users the opportunity to improve procurement requirements. Specific objectives included the demonstration of performance test methods, the seating; these gases/particles entered the fluid path of measurement of 'blowby' (the passage of gases from the pyrotechnic energy source around the activating piston into the valve's fluid path), and the quantification of functional margins for each design. Experiments were conducted at NASA's Langley Research Center on several units for each of the five valve designs. The test methods used for this program measured the forces and energies required to actuate the valves, as well as the energies and the pressures (where possible) delivered by the pyrotechnic sources. Functional performance ranged widely among the designs. Blowby cannot be prevented by o-ring seals; metal-to-metal seals were effective. Functional margin was determined by dividing the energy delivered by the pyrotechnic sources in excess to that required to accomplish the function by the energy required for that function. Two of the five designs had inadequate functional margins with the pyrotechnic cartridges evaluated.

Bement, Laurence J.

1996-01-01

295

Functional Components in Peanuts  

Microsoft Academic Search

Peanut is one of the most widely used legumes due to its nutrition and taste. The fact that is has been recognized recently as a functional food, its evaluation for its role in a heart-healthy diet has received tremendous attention. Functional compounds have been isolated, identified, quantified, and even enhanced to maximize the amount for adequate health benefits. The peanut

Maria Leonora D. L. Francisco; A. V. A. Resurreccion

2008-01-01

296

Functional Magnetic Resonance Imaging  

ERIC Educational Resources Information Center

Functional magnetic resonance imaging (fMRI), with its excellent spatial resolution and ability to visualize networks of neuroanatomical structures involved in complex information processing, has become the dominant technique for the study of brain function and its development. The accessibility of in-vivo pediatric brain-imaging techniques…

Voos, Avery; Pelphrey, Kevin

2013-01-01

297

The Function of Introns  

PubMed Central

The intron–exon architecture of many eukaryotic genes raises the intriguing question of whether this unique organization serves any function, or is it simply a result of the spread of functionless introns in eukaryotic genomes. In this review, we show that introns in contemporary species fulfill a broad spectrum of functions, and are involved in virtually every step of mRNA processing. We propose that this great diversity of intronic functions supports the notion that introns were indeed selfish elements in early eukaryotes, but then independently gained numerous functions in different eukaryotic lineages. We suggest a novel criterion of evolutionary conservation, dubbed intron positional conservation, which can identify functional introns. PMID:22518112

Chorev, Michal; Carmel, Liran

2012-01-01

298

Fragmentation Functions at Belle  

E-print Network

Fragmentation functions (FFs) describe the formation of final state particles from a partonic initial state. Precise knowledge of these functions is a key ingredient in accessing quantities such as the nucleon spin structure in semi-inclusive deep-inelastic scattering and proton proton collisions. However, fragmentation functions can currently not be determined from first principles Quantum Chromodynamics and have to be extracted from experimental data. The Belle experiment at KEK, Japan, provides a large data sample for high precision measurements on e^{+}e^{-} annihilations allowing for first-time or more precise extractions of fragmentation functions. Analyses for extractions of spin-independent (unpolarized FFs) as well as spin-dependent fragmentation functions (interference FFs) at Belle are presented.

Martin Leitgab; for the Belle Collaboration

2012-10-26

299

Plant functional genomics  

NASA Astrophysics Data System (ADS)

Functional genome analysis of plants has entered the high-throughput stage. The complete genome information from key species such as Arabidopsis thaliana and rice is now available and will further boost the application of a range of new technologies to functional plant gene analysis. To broadly assign functions to unknown genes, different fast and multiparallel approaches are currently used and developed. These new technologies are based on known methods but are adapted and improved to accommodate for comprehensive, large-scale gene analysis, i.e. such techniques are novel in the sense that their design allows researchers to analyse many genes at the same time and at an unprecedented pace. Such methods allow analysis of the different constituents of the cell that help to deduce gene function, namely the transcripts, proteins and metabolites. Similarly the phenotypic variations of entire mutant collections can now be analysed in a much faster and more efficient way than before. The different methodologies have developed to form their own fields within the functional genomics technological platform and are termed transcriptomics, proteomics, metabolomics and phenomics. Gene function, however, cannot solely be inferred by using only one such approach. Rather, it is only by bringing together all the information collected by different functional genomic tools that one will be able to unequivocally assign functions to unknown plant genes. This review focuses on current technical developments and their impact on the field of plant functional genomics. The lower plant Physcomitrella is introduced as a new model system for gene function analysis, owing to its high rate of homologous recombination.

Holtorf, Hauke; Guitton, Marie-Christine; Reski, Ralf

2002-04-01

300

Time functions as utilities  

E-print Network

Every time function on spacetime gives a (continuous) total preordering of the spacetime events which respects the notion of causal precedence. The problem of the existence of a (semi-)time function on spacetime and the problem of recovering the causal structure starting from the set of time functions are studied. It is pointed out that these problems have an analog in the field of microeconomics known as utility theory. In a chronological spacetime the semi-time functions correspond to the utilities for the chronological relation, while in a K-causal (stably causal) spacetime the time functions correspond to the utilities for the K^+ relation (Seifert's relation). By exploiting this analogy, we are able to import some mathematical results, most notably Peleg's and Levin's theorems, to the spacetime framework. As a consequence, we prove that a K-causal (i.e. stably causal) spacetime admits a time function and that the time or temporal functions can be used to recover the K^+ (or Seifert) relation which indeed turns out to be the intersection of the time or temporal orderings. This result tells us in which circumstances it is possible to recover the chronological or causal relation starting from the set of time or temporal functions allowed by the spacetime. Moreover, it is proved that a chronological spacetime in which the closure of the causal relation is transitive (for instance a reflective spacetime) admits a semi-time function. Along the way a new proof avoiding smoothing techniques is given that the existence of a time function implies stable causality, and a new short proof of the equivalence between K-causality and stable causality is given which takes advantage of Levin's theorem and smoothing techniques.

E. Minguzzi

2009-09-04

301

Functional Task Test: Data Review  

NASA Technical Reports Server (NTRS)

After space flight there are changes in multiple physiological systems including: Cardiovascular function; Sensorimotor function; and Muscle function. How do changes in these physiological system impact astronaut functional performance?

Cromwell, Ronita

2014-01-01

302

Functional Performance of Pyrovalves  

NASA Technical Reports Server (NTRS)

Following several flight and ground test failures of spacecraft systems using single-shot, 'normally closed' pyrotechnically actuated valves (pyrovalves), a government/industry cooperative program was initiated to assess the functional performance of five qualified designs. The goal of the program was to improve performance-based requirements for the procurement of pyrovalves. Specific objectives included the demonstration of performance test methods, the measurement of 'blowby' (the passage of gases from the pyrotechnic energy source around the activating piston into the valve's fluid path), and the quantification of functional margins for each design. Experiments were conducted in-house at NASA on several units each of the five valve designs. The test methods used for this program measured the forces and energies required to actuate the valves, as well as the energies and the pressures (where possible) delivered by the pyrotechnic sources. Functional performance ranged widely among the designs. Blowby cannot be prevented by o-ring seals; metal-to-metal seals were effective. Functional margin was determined by dividing the energy delivered by the pyrotechnic sources in excess to that required to accomplish the function by the energy required for that function. All but two designs had adequate functional margins with the pyrotechnic cartridges evaluated.

Bement, Laurence J.

1996-01-01

303

The Enzyme Function Initiative†  

PubMed Central

The Enzyme Function Initiative (EFI) was recently established to address the challenge of assigning reliable functions to enzymes discovered in bacterial genome projects; in this Current Topic we review the structure and operations of the EFI. The EFI includes the Superfamily/Genome, Protein, Structure, Computation, and Data/Dissemination Cores that provide the infrastructure for reliably predicting the in vitro functions of unknown enzymes. The initial targets for functional assignment are selected from five functionally diverse superfamilies (amidohydrolase, enolase, glutathione transferase, haloalkanoic acid dehalogenase, and isoprenoid synthase), with five superfamily-specific Bridging Projects experimentally testing the predicted in vitro enzymatic activities. The EFI also includes the Microbiology Core that evaluates the in vivo context of in vitro enzymatic functions and confirms the functional predictions of the EFI. The deliverables of the EFI to the scientific community include: 1) development of a large-scale, multidisciplinary sequence/structure-based strategy for functional assignment of unknown enzymes discovered in genome projects (target selection, protein production, structure determination, computation, experimental enzymology, microbiology, and structure-based annotation); 2) dissemination of the strategy to the community via publications, collaborations, workshops, and symposia; 3) computational and bioinformatic tools for using the strategy; 4) provision of experimental protocols and/or reagents for enzyme production and characterization; and 5) dissemination of data via the EFI’s website, enzymefunction.org. The realization of multidisciplinary strategies for functional assignment will begin to define the full metabolic diversity that exists in nature and will impact basic biochemical and evolutionary understanding, as well as a wide range of applications of central importance to industrial, medicinal and pharmaceutical efforts. PMID:21999478

Gerlt, John A.; Allen, Karen N.; Almo, Steven C.; Armstrong, Richard N.; Babbitt, Patricia C.; Cronan, John E.; Dunaway-Mariano, Debra; Imker, Heidi J.; Jacobson, Matthew P.; Minor, Wladek; Poulter, C. Dale; Raushel, Frank M.; Sali, Andrej; Shoichet, Brian K.; Sweedler, Jonathan V.

2011-01-01

304

A universal functional object  

NASA Technical Reports Server (NTRS)

A scheme is presented for realizing any function, combinational or sequential, in a single universal function scheme, termed the universal function object UF. This scheme is addressed to the problem of the proliferation of the number of parts (cards, chips) necessary for conventional implementation in an LSI technology of a computer system. The UF implementation will use about ten times more circuits than a conventional implementation regardless of the size of the design. The UF approach also includes general-purpose spares for failing circuits. The procedure could be used both at manufacture to increase yields, as well as to achieve automatic repair.

Roth, J. P.

1972-01-01

305

Functional hemodynamic monitoring.  

PubMed

Functional hemodynamic monitoring is the assessment of the dynamic interactions of hemodynamic variables in response to a defined perturbation. Recent interest in functional hemodynamic monitoring for the bedside assessment of cardiovascular insufficiency has heightened with the documentation of its accuracy in predicting volume responsiveness using a wide variety of monitoring devices, both invasive and noninvasive, and across multiple patient groups and clinical conditions. However, volume responsiveness, though important, reflects only part of the overall spectrum of functional physiologic variables that can be measured to define the physiologic state and monitor response to therapy. PMID:25435480

Pinsky, Michael R

2015-01-01

306

Assessment of endothelial function.  

PubMed

In 1986, endothelial function was measured for the first time in patients with atherosclerotic coronary arteries. Since then, several methods for assessment of endothelial function, such as endothelium-dependent vasodilation induced by intra-arterial infusion of vasoactive agents using coronary angiography, Doppler flow guide wire, mercury-filled Silastic strain-gauge plethysmography, flow-mediated vasodilation, reactive hyperemia-peripheral arterial tonometry, and vascular response using an oscillometric method have been performed in humans. This review focuses on the assessment of endothelial function, including measurement history, methodological issues, and clinical perspectives. PMID:25740586

Higashi, Yukihito

2015-03-20

307

Modeling dihadron fragmentation functions  

E-print Network

We present a model for dihadron fragmentation functions, describing the fragmentation of a quark into two unpolarized hadrons. We tune the parameters of our model to the output of the PYTHIA event generator for two-hadron semi-inclusive production in deep inelastic scattering at HERMES. Once the parameters of the model are fixed, we make predictions for other unknown fragmentation functions and for a single-spin asymmetry in the azimuthal distribution of pi+ pi- pairs in semi-inclusive deep inelastic scattering on a transversely polarized target at HERMES and COMPASS. Such asymmetry could be used to measure the quark transversity distribution function.

Alessandro Bacchetta; Marco Radici

2006-08-03

308

Nuclear function of Alus  

PubMed Central

Alus are transposable elements belonging to the short interspersed element family. They occupy over 10% of human genome and have been spreading through genomes over the past 65 million years. In the past, they were considered junk DNA with little function that took up genome volumes. Today, Alus and other transposable elements emerge to be key players in cellular function, including genomic activities, gene expression regulations, and evolution. Here we summarize the current understanding of Alu function in genome and gene expression regulation in human cell nuclei. PMID:24637839

Wang, Chen; Huang, Sui

2014-01-01

309

Functional Analysis Overview Spring 2013  

E-print Network

Engineering: Functional Analysis Module 11 Planetary Defense Level 1 Functional Flow Block Diagram For Threat of the overall system. #12;The Tools of Functional Analysis · Functional Architecture · Functional Flow Block · An example . . . Simple Block Architecture Planetary Defense Program #12;#12;Functional Flow Block Diagrams

Rhoads, James

310

Neuroscience: Towards functional connectomics  

Microsoft Academic Search

To understand the brain, the thousands of synaptic connections made by each of billions of neurons should be mapped and related to neuronal function. First steps towards this formidable goal are now reported. See Articles p.177 & p.183

H. Sebastian Seung

2011-01-01

311

Automating abstraction functions  

E-print Network

Data abstraction has been the dominant structuring paradigm for programs for decades. The essence of a data abstraction is the abstraction function, which relates the concrete program representation to its abstract meaning. ...

Rayside, Derek F

2010-01-01

312

Functional Group Analysis.  

ERIC Educational Resources Information Center

Literature on analytical methods related to the functional groups of 17 chemical compounds is reviewed. These compounds include acids, acid azides, alcohols, aldehydes, ketones, amino acids, aromatic hydrocarbons, carbodiimides, carbohydrates, ethers, nitro compounds, nitrosamines, organometallic compounds, peroxides, phenols, silicon compounds,…

Smith, Walter T., Jr.; Patterson, John M.

1984-01-01

313

Lifestyle and gastric function.  

PubMed

The stomach has a range of functions, including chemical digestion and mechanical breakdown of food, temporary storage of bulk intake, and regulation of the passage of nutrients into the duodenum. Further gastric functions are the nonspecific defense against microbes entering the gastrointestinal tract, preparation of ions as well as liberation of protein-bound cobalamin and production of intrinsic factor for uptake further along the tract, and finally limited absorption of water, alcohol, and some fat-soluble food components including some drugs. These functions are influenced by various lifestyle factors, such as smoking and alcohol intake with interference by Helicobacter pylori colonization. This paper focuses on the interaction between lifestyle and gastric function. PMID:24732183

Kuipers, Ernst J

2014-01-01

314

Platelet Function Tests  

MedlinePLUS

... This type of assay can be used to screen for von Willebrand disease and some platelet function ... present. Bleeding time In the past, the primary screen for platelet dysfunction was the bleeding time. This ...

315

Liver function tests  

MedlinePLUS

... Tierno P, Fenelus M, Bowne WB, Bluth MH. Evaluation of liver function. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 22nd ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap ...

316

Polynomials, Rational Functions  

NSDL National Science Digital Library

A page reserved for the analytic study of polynomial functions studied in calculus classes. History, applications and related fields and subfields; textbooks, reference works, and tutorials; software and tables; selected topics; other web sites with this focus.

Rusin, Dave

317

Reasoning about Function Objects  

NASA Astrophysics Data System (ADS)

Modern object-oriented languages support higher-order implementations through function objects such as delegates in C#, agents in Eiffel, or closures in Scala. Function objects bring a new level of abstraction to the object-oriented programming model, and require a comparable extension to specification and verification techniques. We introduce a verification methodology that extends function objects with auxiliary side-effect free (pure) methods to model logical artifacts: preconditions, postconditions and modifies clauses. These pure methods can be used to specify client code abstractly, that is, independently from specific instantiations of the function objects. To demonstrate the feasibility of our approach, we have implemented an automatic prover, which verifies several non-trivial examples.

Nordio, Martin; Calcagno, Cristiano; Meyer, Bertrand; Müller, Peter; Tschannen, Julian

318

Human Functional Brain Imaging  

E-print Network

forward: speculations on the future of human functional brain imaging 30 4.1 More solution-focused, October 2009 1. The Wellcome Trust has provided substantial funding for neuroscience and mental health

Rambaut, Andrew

319

Biological Function of Prokineticins  

Microsoft Academic Search

Secreted peptides have been implicated in diverse physiological functions. Prokineticins are a pair\\u000a of regulatory peptides that signal through two highly homologous G protein-coupled receptors. Prokineticins\\u000a possess a unique structural motif of five disulfide bonds and conserved N-terminal stretches. Diverse\\u000a biological functions, ranging from development to adult physiology, have been attributed to prokineticins.\\u000a Herein we provide an overview of current knowledge of

Q.-Y. Zhou; R. Meidan

320

Pancreatic function assessment.  

PubMed

Several non invasive tests are available to assess pancreatic function, but no one is routinely used in clinical practice to diagnose chronic pancreatitis, due to their poor sensitivity in diagnosing mild pancreatic insufficiency. (13)C breath tests share the same limits of the other non invasive functional tests, but the mixed triglyceride breath test seems to be useful in finding the correct dosage of enzyme substitutive therapy to prevent malnutrition in patients with known pancreatic insufficiency. PMID:24443071

Laterza, L; Scaldaferri, F; Bruno, G; Agnes, A; Boškoski, I; Ianiro, G; Gerardi, V; Ojetti, V; Alfieri, S; Gasbarrini, A

2013-01-01

321

Center for Functional Nanomaterials  

ScienceCinema

Staff from Brookhaven's new Center for Functional Nanomaterials (CFN) describe how this advanced facility will focus on the development and understanding of nanoscale materials. The CFN provides state-of-the-art capabilities for the fabrication and study of nanoscale materials, with an emphasis on atomic-level tailoring to achieve desired properties and functions. The overarching scientific theme of the CFN is the development and understanding of nanoscale materials that address the Nation's challenges in energy security.

BNL

2009-09-01

322

Assessment of splenic function  

Microsoft Academic Search

Hyposplenic patients are at risk of overwhelming post-splenectomy infection (OPSI), which carries mortality of up to 70%.\\u000a Therefore, preventive measures are warranted. However, patients with diminished splenic function are difficult to identify.\\u000a In this review we discuss immunological, haematological and scintigraphic parameters that can be used to measure splenic function.\\u000a IgM memory B cells are a potential parameter for assessing

A. P. N. A. de Porto; A. J. J. Lammers; R. J. Bennink; I. J. M. ten Berge; P. Speelman; J. B. L. Hoekstra

2010-01-01

323

Obesity and Immune Functions  

Microsoft Academic Search

\\u000a The chapter reviews the literature pertaining to the role of obesity in modulating immune function. Obesity is found in both\\u000a genetic and diet-induced obese animal models as well as in obese humans to impair immune response; both innate and acquired\\u000a immune functions are affected. The immune dysfunction during obesity increases host susceptibility to infections and to chronic\\u000a inflammatory diseases.

Qingde Zhou; Salomon Amar

324

Treatment of functional dyspepsia  

Microsoft Academic Search

Opinion statement  Functional dyspepsia is a common chronic condition. It can have a major impact on quality of life and remains a large burden\\u000a on healthcare resources. Its underlying mechanisms are not fully understood and therapies are mainly empirical. In this review,\\u000a we summarize the best evidence on available therapeutic interventions in functional dyspepsia. Helicobacter pylori eradication, for those infected, is

Silvia Delgado-Aros; Filippo Cremonini; Nicholas J. Talley

2004-01-01

325

Elliptic Functions and Transcendence  

Microsoft Academic Search

Transcendental numbers form a fascinating subject: so little is known about the nature of analytic constants that more research\\u000a is needed in this area. Even when one is interested only in numbers like ? and ? that are related to the classical exponential function, it turns out that elliptic functions are required (so far, this should\\u000a not last forever!) to

Michel Waldschmidt; M. Curie

326

Basics of Endocrine Function  

NSDL National Science Digital Library

This flash video presentation provides an introduction to the basics of the endocrine system. It defines the criteria for determining if a chemical is a hormone and compares the action of hormones with other signalling chemicals and with the way the nervous system functions. The last part of the presentation gives a preview of a flowchart homework activity that can be used by students as a way to learn the function of specific hormones.

Dr. Daniel Brouse (Human Anatomy and Physiology Society)

2008-08-09

327

Inverting onto functions  

Microsoft Academic Search

We look at the hypothesis that all honest onto polynomial-time computable functions have a polynomial-time computable inverse. We show this hypothesis equivalent to several other complexity conjectures including:•In polynomial time, one can find accepting paths of nondeterministic polynomial-time Turing machines that accept ?*.•Every total multivalued nondeterministic function has a polynomial-time computable refinement.•In polynomial time, one can compute satisfying assignments for

Stephen A. Fenner; Lance Fortnow; Ashish V. Naik; John D. Rogers

2003-01-01

328

Inverting Onto Functions  

Microsoft Academic Search

We look at the hypothesis that all honest onto polynomial-time computable functions havea polynomial-time computable inverse. We show this hypothesis equivalent to several othercomplexity conjectures includingffl In polynomial time, one can ?nd accepting paths of nondeterministic polynomial-timeTuring machines that accept \\\\Sigma.ffl Every total multivalued nondeterministic function has a polynomial-time computable re-?nement.ffl In polynomial time, one can compute satisfying...

Stephen A. Fenner; Lance Fortnow; Ashish V. Naik; John D. Rogers

1996-01-01

329

Polarized Antenna Splitting Functions  

SciTech Connect

We consider parton showers based on radiation from QCD dipoles or 'antennae'. These showers are built from 2 {yields} 3 parton splitting processes. The question then arises of what functions replace the Altarelli-Parisi splitting functions in this approach. We give a detailed answer to this question, applicable to antenna showers in which partons carry definite helicity, and to both initial- and final-state emissions.

Larkoski, Andrew J.; Peskin, Michael E.; /SLAC

2009-10-17

330

Structure function monitor  

DOEpatents

Methods and apparatus for a structure function monitor provide for generation of parameters characterizing a refractive medium. In an embodiment, a structure function monitor acquires images of a pupil plane and an image plane and, from these images, retrieves the phase over an aperture, unwraps the retrieved phase, and analyzes the unwrapped retrieved phase. In an embodiment, analysis yields atmospheric parameters measured at spatial scales from zero to the diameter of a telescope used to collect light from a source.

McGraw, John T. (Placitas, NM); Zimmer, Peter C. (Albuquerque, NM); Ackermann, Mark R. (Albuquerque, NM)

2012-01-24

331

Ecological Functions of Wetlands  

Microsoft Academic Search

\\u000a We use the term “function” to mean processes or manifestations of processes. Wetlands probably have hundreds of functions,\\u000a but only a small number are considered important to most people. Some values are based on aesthetics, such as beauty and naturalness,\\u000a but many are economic, such as water quality improvement, wildlife hunting lease value, and sustainable timber production.\\u000a Some of the

John A. Nyman

332

Disentangling different functional roles of evoked K-complex components: Mapping the sleeping brain while quenching sensory processing.  

PubMed

During non-REM sleep the largest EEG response evoked by sensory stimulation is the K-complex (eKC), composed of an initial positive bump (P200) followed by a bistable cortical response: a giant negative deflection (N550) and a large positive one (P900), respectively reflecting down states and up states of < 1 Hz oscillations.Sensory-modality-independent topology of N550 and P900, with maximal detection rate on fronto-central areas, has been consistently reported, suggesting that sensory inputs arise to the cortex avoiding specific primary sensory areas. However, these studies neglected latencies of all KC components as a function of electrode sites.Our aim is to identify, component by component, which topological/dynamical properties of eKCs depend on stimulus modality and which are mainly related to local cortical properties. We measured temporal and morphological features of acoustic, tactile and visual eKCs to disentangle specific sensory excitatory activities from aspecific responses due to local proneness to bistability, measured by means of the N550 descending steepness (synchronization in falling into down state).While confirming the sensory-modality independence of N550 and P900 topology with maximal detection rate in fronto-central areas, four main original results emerge from this study: (i) the topology of P200 latency depends on the sensory modality with earliest waves in the stimulation-related primary sensory areas; (ii) P200 rapidly travels as a cortical excitation; (iii) P200-like excitations when KCs are not evoked are detected over the scalp with significantly smaller amplitudes in fronto-central areas, compared to eKC P200s; and (iv) N550 latency mirrors its mean local steepness which is a function of topological proneness to bistability.From these results we can describe the emergence N550/P900 complex as the interplay between a waxing P200 cortical travel and higher fronto-central proneness to bistability.In conclusion, eKCs exhibit a physiological dichotomy: P200 acts as a traveling cortical excitation whose function is to induce the bistable cortical response (N550/P900), which in turn is crucial for maintaining sleep and unconsciousness. PMID:24513527

Laurino, Marco; Menicucci, Danilo; Piarulli, Andrea; Mastorci, Francesca; Bedini, Remo; Allegrini, Paolo; Gemignani, Angelo

2014-02-01

333

Completeness of Decoherence Functionals  

E-print Network

The basic ingredients of the `consistent histories' approach to a generalized quantum theory are `histories'and decoherence functionals. The main aim of this program is to find and to study the behaviour of consistent sets associated with a particular decoherence functional $d$. In its recent formulation by Isham it is natural to identify the space $\\UP$ of propositions about histories with an orthoalgebra or lattice. When $\\UP$ is given by the lattice of projectors $\\PV$ in some Hilbert space $\\V$, consistent sets correspond to certain partitions of the unit operator in $\\V$ into mutually orthogonal projectors $\\{\\a_1,\\a_2,\\ldots\\}$, such that the function $d(\\a,\\a)$ is a probability distribution on the boolean algebra generated by $\\{\\a_1,\\a_2,\\ldots\\}$. Using the classification theorem for decoherence functionals, proven previously, we show that in the case where $\\V$ is some separable Hilbert space there exists for each partition of the unit operator into a set of mutually orthogonal projectors, and for any probability distribution $p(\\a)$ on the corresponding boolean algebra, decoherence functionals $d$ with respect to which this set is consistent and which are such that for the probability functions $d(\\a,\\a)=p(\\a)$ holds.

S. Schreckenberg

1995-06-12

334

Confinement from correlation functions  

NASA Astrophysics Data System (ADS)

We compute the Polyakov loop potential in Yang-Mills theory from the fully dressed primitively divergent correlation functions only. This is done in a variety of functional approaches ranging from functional renormalization group equations over Dyson-Schwinger equations to two-particle irreducible functionals. We present a confinement criterion that links the infrared behavior of propagators and vertices to the Polyakov loop expectation value. The present work extends the works of [J. Braun , Phys. Lett. B 684, 262 (2010)PYLBAJ0370-2693; F. Marhauser and J. M. Pawlowski, arXiv:0812.1144; J. Braun , Eur. Phys. J. C 70, 689 (2010)EPCFFB1434-6044] to general functional methods and sharpens the confinement criterion presented there. The computations are based on the thermal correlation functions in the Landau gauge calculated in [L. Fister and J. M. Pawlowski, arXiv:1112.5440; L. Fister and J. M. Pawlowski, arXiv:1112.5429; L. Fister, Ph.D. thesis, Heidelberg University, 2012].

Fister, Leonard; Pawlowski, Jan M.

2013-08-01

335

The Achilles Functional Index.  

PubMed

The literature regarding the management of spontaneous rupture of the Achilles tendon is controversial and confusing. The relative infrequency of the condition in any one center prohibits the completion of well-designed clinical studies. Many of the disputes could be addressed and innovations tested if an appropriate animal model were available. We present a method for evaluating Achilles tendon function from measurements of the prints, preserved in bromphenol-blue-impregnated photocopying paper, of the hindfeet of walking rats. The stimulus for this study was derived from de Medinaceli's method for assessing the functional condition of rat sciatic nerves (de Medinaceli L, Freed WJ, Wyatt RJ: An index of the functional condition of rat sciatic nerve based on measurements made from walking tracks. Exp Neurol 77:634-643, 1982). Four variables were measured from these walking tracks, and comparisons between the damaged (experimental) and intact (normal) side were converted to proportional deficits. The relative contribution of each parameter to the overall deficit was determined by multiple linear regression analysis, and the variables were weighted accordingly to obtain an "Achilles Functional Index" (AFI). A sham operation produced no functional deficit, whereas animals subjected to a 0.5-cm midsubstance Achilles tendon defect demonstrated a markedly impaired AFI. Animals with repaired transected Achilles tendons also demonstrated a significant, but less severely impaired AFI. The functional deficit in this repair group returned to control values by postoperative day 15, whereas animals with a defect remained impaired at day 15. Furthermore, an excellent correlation was found between the functional recovery and biomechanical properties (ultimate failure load) of the healing tendon (r = 0.94; p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1569503

Murrell, G A; Lilly, E G; Davies, H; Best, T M; Goldner, R D; Seaber, A V

1992-05-01

336

Structure and composition of the Trinil femora: Functional and taxonomic implications.  

PubMed

The original hominin femur (Femur I) and calotte discovered at Trinil, Java by Eugene Dubois in 1891/1892 played a key role in the early history of human paleontology by purportedly demonstrating the contemporaneity of archaic cranial form with modern human erect (bipedal) posture. On this basis, both specimens were subsequently assigned to Pithecanthropus erectus, later transferred to Homo erectus. However, chronological and phylogenetic links between the two have been questioned from the beginning. Four additional hominin partial femora (Femora II-V) from Trinil were subsequently described but have played a relatively minor part in evolutionary scenarios. Here we present the results of a new analysis of structural and density characteristics of the Trinil femora obtained using computed tomography. Trinil Femur I shows none of the characteristics typical of early Homo femora from elsewhere in Asia or Africa, including a relatively long neck, increased mediolateral bending rigidity of the mid-proximal shaft, or a low position of minimum mediolateral breath on the shaft. In contrast, Femora II-V all demonstrate features that are more consistent with this pattern. In addition, material density distributions within the specimens imply more recent and less complete fossilization of Femur I than Femora II-V. Thus, it is very likely that Trinil Femur I derives from a much more recent time period than the calotte, while the less famous and less complete Femora II-V may represent H. erectus at Trinil. The morphological variation within the Trinil femora can be attributed to broader changes in pelvic morphology occurring within the Homo lineage between the Early and late Middle Pleistocene. PMID:25681015

Ruff, Christopher B; Puymerail, Laurent; Macchiarelli, Roberto; Sipla, Justin; Ciochon, Russell L

2015-03-01

337

OPERATOR-VALUED BERGMAN INNER FUNCTIONS AS TRANSFER FUNCTIONS  

E-print Network

OPERATOR-VALUED BERGMAN INNER FUNCTIONS AS TRANSFER FUNCTIONS). Operator-valued analytic functions of the form (0.1) has a natural interpreta* *tion as transfer functions- mula the operator-valued Bergman inner functions for a class of vector-v* *alued standard

Olofsson, Anders

338

Functional (Nonulcer) Dyspepsia.  

PubMed

Functional (nonulcer) dyspepsia refers to upper abdominal pain or discomfort with or without symptoms of early satiety, nausea, or vomiting with no definable organic cause. The current Rome II criteria help to diagnose functional dyspepsia and avoid misdiagnosis of gastroesophageal reflux disease and irritable bowel syndrome as functional dyspepsia. Assessment of gastric emptying with scintigraphy or breath testing may be useful in identifying delayed gastric emptying in patients with dyspeptic symptoms and may be helpful in patient management. Electrogastrography is a noninvasive test that evaluates for gastric dysrhythmias. Satiety testing is being evaluated as an indirect test for impaired fundic relaxation and visceral hypersensitivity. The symptom response to Helicobacter pylori therapy in patients with functional dyspepsia and a negative endoscopy examination but a positive H. pylori test is marginal. Lifestyle modifications often are suggested for initial treatment of functional dyspepsia. Dietary changes such as frequent small meals, low-fat diet, and avoidance of certain aggravating foods may improve symptoms. Additional measures include cessation of smoking, avoiding excess alcohol intake, and minimizing coffee intake. Antacids and over-the-counter histamine type 2 receptor antagonists may be helpful as an "on-demand" therapy for intermittent symptoms. They are safe and relatively inexpensive. Different subgroups of functional dyspepsia are based on the predominant symptom and may help in choosing an appropriate drug to initiate therapy. If the predominant symptom is epigastric pain (ulcer-like functional dyspepsia), histamine-2 receptor antagonists or proton pump inhibitors are the initial treatment of choice. If fullness, bloating, early satiety or nausea is the predominant complaint (dysmotility-like functional dyspepsia), a prokinetic agent may help. Metoclopramide is the only available effective prokinetic agent at present. If metoclopramide is used, short-term treatment and discussion of possible side effects with the patient are advised. If there is no response to these initial treatments, switching therapy from proton pump inhibitor to prokinetic or vice versa can be tried. If these treatment options fail, patient re-evaluation for other disorders (including other functional bowel disorders) is advised. A low-dose tricyclic antidepressant at bedtime may be helpful for treatment of visceral hypersensitivity. PMID:11879596

Panganamamula, Kashyap V.; Fisher, Robert S.; Parkman, Henry P.

2002-04-01

339

Functional imaging and endoscopy  

PubMed Central

The emergence of endoscopy for the diagnosis of gastrointestinal diseases and the treatment of gastrointestinal diseases has brought great changes. The mere observation of anatomy with the imaging mode using modern endoscopy has played a significant role in this regard. However, increasing numbers of endoscopies have exposed additional deficiencies and defects such as anatomically similar diseases. Endoscopy can be used to examine lesions that are difficult to identify and diagnose. Early disease detection requires that substantive changes in biological function should be observed, but in the absence of marked morphological changes, endoscopic detection and diagnosis are difficult. Disease detection requires not only anatomic but also functional imaging to achieve a comprehensive interpretation and understanding. Therefore, we must ask if endoscopic examination can be integrated with both anatomic imaging and functional imaging. In recent years, as molecular biology and medical imaging technology have further developed, more functional imaging methods have emerged. This paper is a review of the literature related to endoscopic optical imaging methods in the hopes of initiating integration of functional imaging and anatomical imaging to yield a new and more effective type of endoscopy. PMID:22090783

Zhang, Jian-Guo; Liu, Hai-Feng

2011-01-01

340

The Tensor Distribution Function  

PubMed Central

Diffusion weighted magnetic resonance imaging is a powerful tool that can be employed to study white matter microstructure by examining the 3D displacement profile of water molecules in brain tissue. By applying diffusion-sensitized gradients along a minimum of six directions, second-order tensors (represented by three-by-three positive definite matrices) can be computed to model dominant diffusion processes. However, conventional DTI is not sufficient to resolve more complicated white matter configurations, e.g., crossing fiber tracts. Recently, a number of high-angular resolution schemes with more than six gradient directions have been employed to address this issue. In this article, we introduce the tensor distribution function (TDF), a probability function defined on the space of symmetric positive definite matrices. Using the calculus of variations, we solve the TDF that optimally describes the observed data. Here, fiber crossing is modeled as an ensemble of Gaussian diffusion processes with weights specified by the TDF. Once this optimal TDF is determined, the orientation distribution function (ODF) can easily be computed by analytic integration of the resulting displacement probability function. Moreover, a tensor orientation distribution function (TOD) may also be derived from the TDF, allowing for the estimation of principal fiber directions and their corresponding eigenvalues. PMID:19097208

Leow, A. D.; Zhu, S.; Zhan, L.; McMahon, K.; de Zubicaray, G. I.; Meredith, M.; Wright, M. J.; Toga, A. W.; Thompson, P. M.

2009-01-01

341

Functional Capacity Evaluation & Disability  

PubMed Central

Function, Impairment, and Disability are words in which many physicians have little interest. Most physicians are trained to deal with structure and physiology and not function and disability. The purpose of this article is to address some of the common questions that many physicians have with the use of functional capacity evaluation and disability and also to provide a unifying model that can explain the medical and societal variables in predicting disability. We will first define the functional capacity evaluation (FCE) and explore the different types available as well as their uses. We will review several studies exploring the validity and reliability of the FCE on healthy and chronic pain patients. We will examine the few studies that look into whether an FCE is predictive of return to work and whether an FCE is predictive of disability. In the second half of this article, we will focus on the Assessment of Disability from the origins of the United States Social Security Administration to a bold new concept, the World Health Organization's International Classification of Function, Disability and Health. PMID:17907444

Chen, Joseph J

2007-01-01

342

Functional peptides by design  

NASA Astrophysics Data System (ADS)

Proteins are nature's machines, built to function in many different ways. The ability to form so many functional molecules from the same few building blocks relies on the ability of these molecules to fold into specific structures. In this work, functional peptides are designed based on the information that has been gathered from nature concerning the relationships between sequence and structure. Chemists are not limited to naturally occurring amino acids, but may use any synthetically accessible residue imaginable. Herein, three novel amino acids are synthesized for facile incorporation into peptide sequences. These residues are designed to play a role in peptide folding through the formation of buried salt-bridges. They are small basic residues with varying hydrophobicity, and their ability to specify novel folds when incorporated into GCN4-p1 is demonstrated. Design is used to link intramolecular folding of another peptide to its function. MAX1 is designed to fold into a beta-hairpin structure upon the addition of distinct environmental stimuli. Once folded, this peptide self-assembles into a hydrogel material. Many applications can be envisioned for this hydrogel material, including its use as a tissue engineering scaffold. Cytocompatibility and antimicrobial activity studies demonstrate the ability of this hydrogel to support the selective proliferation of mammalian cells over certain bacterial strains. Thus, function has been successfully designed into a peptide.

Kretsinger, Juliana K.

343

Sperm functional tests.  

PubMed

Several semen parameters are used to discriminate the fertile male from the subfertile male. The most widely used parameters are sperm concentration, motility, progressive motility, and sperm morphology. Semen analysis is usually applied as described in the World Health Organization manual for semen analysis. In addition to a routine semen analysis, sperm functional tests have been described for many years, which in most cases are regarded as research tools and not part of the routine semen testing in an infertility clinic. In this review we report on the value of four sperm function tests: the sperm penetration assay, the sperm-zona pellucida binding tests, the acrosome reaction, and the hyaluronan binding assay. For each test we describe the current value, the indication for performing the test, how to interpret the results, and its therapeutic implications. Our data show that sperm functional assays are highly predictive of IVF outcome results and have the potential to assist in clinical decision making, especially to avoid the current long-standing treatment with IUI and to direct the patients to intracytoplasmic sperm injection without delay when sperm functional testing fails. We believe that advances in molecular biology techniques will allow us to develop simpler sperm function assays in the near future. This will undoubtedly help clinicians in optimizing male factor infertility diagnosis and treatment. PMID:25450304

Oehninger, Sergio; Franken, Daniel R; Ombelet, Willem

2014-12-01

344

CAVEOLINS AND LUNG FUNCTION  

PubMed Central

The primary function of the mammalian lung is to facilitate diffusion of oxygen to venous blood and to ventilate carbon dioxide produced by catabolic reactions within cells. However, it is also responsible for a variety of other important functions, including host defense and production of vasoactive agents to regulate not only systemic blood pressure, but also water, electrolyte and acid-base balance. Caveolin-1 is highly expressed in the majority of cell types in the lung, including epithelial, endothelial, smooth muscle, connective tissue cells, and alveolar macrophages. Deletion of caveolin-1 in these cells results in major functional aberrations, suggesting that caveolin-1 may be crucial to lung homeostasis and development. Furthermore, generation of mutant mice that under-express caveolin-1 results in severe functional distortion with phenotypes covering practically the entire spectrum of known lung diseases, including pulmonary hypertension, fibrosis, increased endothelial permeability, and immune defects. In this Chapter, we outline the current state of knowledge regarding caveolin-1-dependent regulation of pulmonary cell functions and discuss recent research findings on the role of caveolin-1 in various pulmonary disease states, including obstructive and fibrotic pulmonary vascular and inflammatory diseases. PMID:22411320

Maniatis, Nikolaos A.; Chernaya, Olga; Shinin, Vasily; Minshall, Richard D.

2012-01-01

345

High-throughput sequence analysis of Ciona intestinalis SL trans-spliced mRNAs: alternative expression modes and gene function correlates.  

PubMed

Pre-mRNA 5' spliced-leader (SL) trans-splicing occurs in some metazoan groups but not in others. Genome-wide characterization of the trans-spliced mRNA subpopulation has not yet been reported for any metazoan. We carried out a high-throughput analysis of the SL trans-spliced mRNA population of the ascidian tunicate Ciona intestinalis by 454 Life Sciences (Roche) pyrosequencing of SL-PCR-amplified random-primed reverse transcripts of tailbud embryo RNA. We obtained approximately 250,000 high-quality reads corresponding to 8790 genes, approximately 58% of the Ciona total gene number. The great depth of this data revealed new aspects of trans-splicing, including the existence of a significant class of "infrequently trans-spliced" genes, accounting for approximately 28% of represented genes, that generate largely non-trans-spliced mRNAs, but also produce trans-spliced mRNAs, in part through alternative promoter use. Thus, the conventional qualitative dichotomy of trans-spliced versus non-trans-spliced genes should be supplanted by a more accurate quantitative view recognizing frequently and infrequently trans-spliced gene categories. Our data include reads representing approximately 80% of Ciona frequently trans-spliced genes. Our analysis also revealed significant use of closely spaced alternative trans-splice acceptor sites which further underscores the mechanistic similarity of cis- and trans-splicing and indicates that the prevalence of +/-3-nt alternative splicing events at tandem acceptor sites, NAGNAG, is driven by spliceosomal mechanisms, and not nonsense-mediated decay, or selection at the protein level. The breadth of gene representation data enabled us to find new correlations between trans-splicing status and gene function, namely the overrepresentation in the frequently trans-spliced gene class of genes associated with plasma/endomembrane system, Ca(2+) homeostasis, and actin cytoskeleton. PMID:20212022

Matsumoto, Jun; Dewar, Ken; Wasserscheid, Jessica; Wiley, Graham B; Macmil, Simone L; Roe, Bruce A; Zeller, Robert W; Satou, Yutaka; Hastings, Kenneth E M

2010-05-01

346

High-throughput sequence analysis of Ciona intestinalis SL trans-spliced mRNAs: Alternative expression modes and gene function correlates  

PubMed Central

Pre-mRNA 5? spliced-leader (SL) trans-splicing occurs in some metazoan groups but not in others. Genome-wide characterization of the trans-spliced mRNA subpopulation has not yet been reported for any metazoan. We carried out a high-throughput analysis of the SL trans-spliced mRNA population of the ascidian tunicate Ciona intestinalis by 454 Life Sciences (Roche) pyrosequencing of SL-PCR-amplified random-primed reverse transcripts of tailbud embryo RNA. We obtained ?250,000 high-quality reads corresponding to 8790 genes, ?58% of the Ciona total gene number. The great depth of this data revealed new aspects of trans-splicing, including the existence of a significant class of “infrequently trans-spliced” genes, accounting for ?28% of represented genes, that generate largely non-trans-spliced mRNAs, but also produce trans-spliced mRNAs, in part through alternative promoter use. Thus, the conventional qualitative dichotomy of trans-spliced versus non-trans-spliced genes should be supplanted by a more accurate quantitative view recognizing frequently and infrequently trans-spliced gene categories. Our data include reads representing ?80% of Ciona frequently trans-spliced genes. Our analysis also revealed significant use of closely spaced alternative trans-splice acceptor sites which further underscores the mechanistic similarity of cis- and trans-splicing and indicates that the prevalence of ±3-nt alternative splicing events at tandem acceptor sites, NAGNAG, is driven by spliceosomal mechanisms, and not nonsense-mediated decay, or selection at the protein level. The breadth of gene representation data enabled us to find new correlations between trans-splicing status and gene function, namely the overrepresentation in the frequently trans-spliced gene class of genes associated with plasma/endomembrane system, Ca2+ homeostasis, and actin cytoskeleton. PMID:20212022

Matsumoto, Jun; Dewar, Ken; Wasserscheid, Jessica; Wiley, Graham B.; Macmil, Simone L.; Roe, Bruce A.; Zeller, Robert W.; Satou, Yutaka; Hastings, Kenneth E.M.

2010-01-01

347

Megakaryocyte structure and function.  

PubMed

Recent advances in the understanding of megakaryocyte (MK) function largely have been made through the careful observation of the morphological and structural events underlying MK development. Ultrastructural localization of enzymatic activities has facilitated the specific recognition of their committed diploid precursors. Observation of the sequential features of endomitosis demonstrates that although similar to normal mitosis, cell division aborts at the anaphase stage. The ability of thrombopoietin to induce the full maturation MKs in vitro not only facilitates platelet release but has increased our knowledge of various subcellular aspects of the phenomenon and eventually will improve the in vivo detection of the site of platelet formation and shedding. Finally, the structural and functional consequences of MK molecular dysfunction leading to thrombocytopenia or myelofibrosis can now be investigated because of the development of transgenic animal models. This review aims to incorporate these new findings within the classical knowledge of MK structure related to its function. PMID:10468153

Cramer, E M

1999-09-01

348

Functional biomimetic optical devices  

NASA Astrophysics Data System (ADS)

The diversity of biological sensing and biocatalysis is astounding. A considerable effort has been directed at not only understanding the mechanism of these biological processes, but also how this activity can be maintained or duplicated in an artificial environment. We will present work on the formation of functional optical devices that convert biological responses into optical signals through changes in diffraction efficiency and reflection angle. By incorporating biomolecules into monomer systems that can be cured using a two-photon polymerization mechanism, greater spatial resolution and increased biological viability can be achieved. The polymer can be nanopatterned using ultrafast nonlinear holography to create a functional BioMEMS device. Additionally, we will discuss the characterization of the biomolecules and the processing of the gratings that incorporate these functional proteins. This approach is a first step towards the development of a hybrid organic-inorganic composite device.

Naik, Rajesh R.; Brott, Lawrence L.; Kirkpatrick, Sean M.; Stone, Morley O.

2001-11-01

349

Functional sympatholysis in hypertension.  

PubMed

Sympathetic vasoconstriction is normally attenuated in exercising muscle by local changes in muscle metabolites and other substances that reduce vascular responsiveness to ?-adrenergic receptor activation. Termed functional sympatholysis, this protective mechanism is thought to optimize muscle blood flow distribution to match perfusion with metabolic demand. Emerging evidence from both animal and human studies indicate that functional sympatholysis is impaired in hypertension and may constitute an important underlying cause of skeletal muscle malperfusion during exercise in this common cardiovascular condition. Findings from studies of animal models of hypertension and patients with essential hypertension will be integrated in this review to provide insight into the underlying mechanisms responsible for inappropriate sympathetic vasoconstriction in exercising muscle and the treatment options that may restore functional sympatholysis and improve muscle perfusion during exercise. PMID:25458424

Thomas, Gail D

2015-03-01

350

Protein Functionalized Nanodiamond Arrays  

PubMed Central

Various nanoscale elements are currently being explored for bio-applications, such as in bio-images, bio-detection, and bio-sensors. Among them, nanodiamonds possess remarkable features such as low bio-cytotoxicity, good optical property in fluorescent and Raman spectra, and good photostability for bio-applications. In this work, we devise techniques to position functionalized nanodiamonds on self-assembled monolayer (SAMs) arrays adsorbed on silicon and ITO substrates surface using electron beam lithography techniques. The nanodiamond arrays were functionalized with lysozyme to target a certain biomolecule or protein specifically. The optical properties of the nanodiamond-protein complex arrays were characterized by a high throughput confocal microscope. The synthesized nanodiamond-lysozyme complex arrays were found to still retain their functionality in interacting with E. coli. PMID:20672037

2010-01-01

351

Scaling function, spectral function, and nucleon momentum distribution in nuclei  

E-print Network

The link between the scaling function extracted from the analysis of (e,e') cross sections and the spectral function/momentum distribution in nuclei is revisited. Several descriptions of the spectral function based on the ...

Antonov, A. N.

352

Adaptive multiconfigurational wave functions  

SciTech Connect

A method is suggested to build simple multiconfigurational wave functions specified uniquely by an energy cutoff ?. These are constructed from a model space containing determinants with energy relative to that of the most stable determinant no greater than ?. The resulting ?-CI wave function is adaptive, being able to represent both single-reference and multireference electronic states. We also consider a more compact wave function parameterization (?+SD-CI), which is based on a small ?-CI reference and adds a selection of all the singly and doubly excited determinants generated from it. We report two heuristic algorithms to build ?-CI wave functions. The first is based on an approximate prescreening of the full configuration interaction space, while the second performs a breadth-first search coupled with pruning. The ?-CI and ?+SD-CI approaches are used to compute the dissociation curve of N{sub 2} and the potential energy curves for the first three singlet states of C{sub 2}. Special attention is paid to the issue of energy discontinuities caused by changes in the size of the ?-CI wave function along the potential energy curve. This problem is shown to be solvable by smoothing the matrix elements of the Hamiltonian. Our last example, involving the Cu{sub 2}O{sub 2}{sup 2+} core, illustrates an alternative use of the ?-CI method: as a tool to both estimate the multireference character of a wave function and to create a compact model space to be used in subsequent high-level multireference coupled cluster computations.

Evangelista, Francesco A., E-mail: francesco.evangelista@emory.edu [Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322 (United States)

2014-03-28

353

Muscle and prosthesis contributions to amputee walking mechanics: A modeling study  

E-print Network

Muscle and prosthesis contributions to amputee walking mechanics: A modeling study Anne K the functional use of the ankle muscles, which are critical during walking to provide body support, forward propulsion, leg-swing initiation and mediolateral balance. Thus, either muscles must compensate

Ben-Yakar, Adela

354

Functionalization of carbon nanotubes  

NASA Technical Reports Server (NTRS)

Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H.sub.2 or F.sub.2 or C.sub.nH.sub.m) is irradiated to provide a cold plasma of selected target particles, such as atomic H or F, in a first chamber. The target particles are directed toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec.

Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)

2007-01-01

355

Functionalization of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H2, or F2, or CnHm) is irradiated to provide a cold plasma of selected target particles, such as atomic H or F, in a first chamber. The target particles are directed toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec.

Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)

2007-01-01

356

GADRAS Detector Response Function.  

SciTech Connect

The Gamma Detector Response and Analysis Software (GADRAS) applies a Detector Response Function (DRF) to compute the output of gamma-ray and neutron detectors when they are exposed to radiation sources. The DRF is fundamental to the ability to perform forward calculations (i.e., computation of the response of a detector to a known source), as well as the ability to analyze spectra to deduce the types and quantities of radioactive material to which the detectors are exposed. This document describes how gamma-ray spectra are computed and the significance of response function parameters that define characteristics of particular detectors.

Mitchell, Dean J.; Harding, Lee; Thoreson, Gregory G; Horne, Steven M.

2014-11-01

357

Peroxisome Biogenesis and Function  

PubMed Central

Peroxisomes are small and single membrane-delimited organelles that execute numerous metabolic reactions and have pivotal roles in plant growth and development. In recent years, forward and reverse genetic studies along with biochemical and cell biological analyses in Arabidopsis have enabled researchers to identify many peroxisome proteins and elucidate their functions. This review focuses on the advances in our understanding of peroxisome biogenesis and metabolism, and further explores the contribution of large-scale analysis, such as in sillco predictions and proteomics, in augmenting our knowledge of peroxisome function In Arabidopsis. PMID:22303249

Kaur, Navneet; Reumann, Sigrun; Hu, Jianping

2009-01-01

358

Heart Rate and Function  

NSDL National Science Digital Library

The purpose of this activity is to discover and learn about heart rate and the function of the heart. The students will investigate whether their hearts beat slower/faster at different times; develop an understanding of why their hearts beat slower/faster at different times; use data to develop an explanation of why their hearts beat slower/faster at different times; be aware of the effect of exercise on respiration; and be able to describe the major function of the heart.

Mr. Mike Peterson (Frazer Public School)

1999-07-01

359

Adaptive Transfer Function Networks  

SciTech Connect

Real-time pattern classification and time-series forecasting applications continue to drive artificial neural network (ANN) technology. As ANNs increase in complexity, the throughput of digital computer simulations decreases. A novel ANN, the Adaptive Transfer Function Network (ATF-Net), directly addresses the issue of throughput. ATF-Nets are global mapping equations generated by the superposition of ensembles of neurodes having arbitrary continuous functions receiving encoded input data. ATF-Nets may be implemented on parallel digital computers. An example is presented which illustrates a four-fold increase in computational throughput.

Goulding, J.R. [Los Alamos National Lab., NM (United States)]|[Portland State Univ., OR (United States). Dept. of Electrical Engineering

1993-06-01

360

Adaptive Transfer Function Networks  

SciTech Connect

Real-time pattern classification and time-series forecasting applications continue to drive artificial neural network (ANN) technology. As ANNs increase in complexity, the throughput of digital computer simulations decreases. A novel ANN, the Adaptive Transfer Function Network (ATF-Net), directly addresses the issue of throughput. ATF-Nets are global mapping equations generated by the superposition of ensembles of neurodes having arbitrary continuous functions receiving encoded input data. ATF-Nets may be implemented on parallel digital computers. An example is presented which illustrates a four-fold increase in computational throughput.

Goulding, J.R. (Los Alamos National Lab., NM (United States) Portland State Univ., OR (United States). Dept. of Electrical Engineering)

1993-01-01

361

Mollusc Form and Function  

NSDL National Science Digital Library

This Zoo Lab web page features information regarding mollusc form and function. Links are provided to images of snail radula, Veliger larvae, Glochidium larva, squid dissection mount, male squid dissection, freshwater clam dissection mount, freshwater mussel dissection, and a clam model. Each image is labeled and accompanied by a caption describing the function of major structures. The page was developed as a student study guide for practical exams and also provides an outline of the material presented in the lecture portion of the course. It can also provide a "virtual laboratory" experience for those who do not have access to these materials as well as a source of basic zoological information.

Rick Gillis

362

Structure and Function  

NSDL National Science Digital Library

Structure and Function is a graduate-level professional development course designed to enhance your understanding and teaching of life science. In two sessions, you will investigate life science topics using hands-on activities and online resources including video segments, interactive activities, readings, and other multimedia materials. These resources are drawn from Teachers' Domain, WGBH's digital library service.

2010-01-01

363

Iridescence: a functional perspective  

PubMed Central

In animals, iridescence is generated by the interaction of light with biological tissues that are nanostructured to produce thin films or diffraction gratings. Uniquely among animal visual signals, the study of iridescent coloration contributes to biological and physical sciences by enhancing our understanding of the evolution of communication strategies, and by providing insights into physical optics and inspiring biomimetic technologies useful to humans. Iridescent colours are found in a broad diversity of animal taxa ranging from diminutive marine copepods to terrestrial insects and birds. Iridescent coloration has received a surge of research interest of late, and studies have focused on both characterizing the nanostructures responsible for producing iridescence and identifying the behavioural functions of iridescent colours. In this paper, we begin with a brief description of colour production mechanisms in animals and provide a general overview of the taxonomic distribution of iridescent colours. We then highlight unique properties of iridescent signals and review the proposed functions of iridescent coloration, focusing, in particular, on the ways in which iridescent colours allow animals to communicate with conspecifics and avoid predators. We conclude with a brief overview of non-communicative functions of iridescence in animals. Despite the vast amount of recent work on animal iridescence, our review reveals that many proposed functions of iridescent coloration remain virtually unexplored, and this area is clearly ripe for future research. PMID:19336344

Doucet, Stéphanie M.; Meadows, Melissa G.

2009-01-01

364

IL13 EFFECTOR FUNCTIONS  

Microsoft Academic Search

? Abstract IL-13 was first recognized for its effects on B cells and monocytes, where it upregulated class II expression, promoted IgE class switching and inhibited inflammatory cytokine production. It was also thought to be functionally redundant with IL-4. However, studies conducted with knockout mice, neutralizing antibodies, and novel antagonists demonstrate that IL-13 possesses several unique effector func- tions that

Thomas A. Wynn

2003-01-01

365

Function Transformation without Reinforcement  

ERIC Educational Resources Information Center

In studies of function transformation, participants initially are taught to match stimuli in the presence of a contextual cue, X; the stimuli to be matched bear some formal relation to each other, for example, a relation of opposition or difference. In a second phase, the participants are taught to match arbitrary stimuli (say, A and B) in the…

Tonneau, Francois; Arreola, Fara; Martinez, Alma Gabriela

2006-01-01

366

Transfer function matrix  

NASA Technical Reports Server (NTRS)

Given a multivariable system, it is proved that the numerator matrix N(s) of the transfer function evaluated at any system pole either has unity rank or is a null matrix. It is also shown that N(s) evaluated at any transmission zero of the system has rank deficiency. Examples are given for illustration.

Seraji, H.

1987-01-01

367

Functional Extended Redundancy Analysis  

ERIC Educational Resources Information Center

We propose a functional version of extended redundancy analysis that examines directional relationships among several sets of multivariate variables. As in extended redundancy analysis, the proposed method posits that a weighed composite of each set of exogenous variables influences a set of endogenous variables. It further considers endogenous…

Hwang, Heungsun; Suk, Hye Won; Lee, Jang-Han; Moskowitz, D. S.; Lim, Jooseop

2012-01-01

368

Chemistry Teachers' Functional Paradigms.  

ERIC Educational Resources Information Center

Discusses a study which examined the interpretive process used by high school chemistry teachers in translating curriculum materials into classroom practice. Results indicate that differences exist among teachers but that commonalities are greater. Explains the functional paradigm concept and its value for the interpretation of curriculum…

Lantz, Oliver; Kass, Heidi

1987-01-01

369

Function Inheritance William Cook  

E-print Network

Function Inheritance William Cook University of Texas at Austin Department of Computer Science Join9 = mod9 fib = mod9 (fix gFib) optimize computation of just fib 9 fibInh9 = fix(mod9 . gFib) optimize computation for all n > 9 Inheritance #12;Summary Mod9 Fib Mod9 FibfibInh9 fib9 #12;· Composable

Cook, William R.

370

Minkowski Functionals in Cosmology  

E-print Network

Minkowski functionals provide a novel tool to characterize the large-scale galaxy distribution in the Universe. Here we give a brief tutorial on the basic features of these morphological measures and indicate their practical application for simulation data and galaxy redshift catalogues as examples.

J. Schmalzing; M. Kerscher; T. Buchert

1995-10-05

371

Functional esophageal disorders  

PubMed Central

The functional esophageal disorders include globus, rumination syndrome, and symptoms that typify esophageal diseases (chest pain, heartburn, and dysphagia). Factors responsible for symptom production are poorly understood. The criteria for diagnosis rest not only on compatible symptoms but also on exclusion of structural and metabolic disorders that might mimic the functional disorders. Additionally, a functional diagnosis is precluded by the presence of a pathology-based motor disorder or pathological reflux, defined by evidence of reflux esophagitis or abnormal acid exposure time during ambulatory esophageal pH monitoring. Management is largely empirical, although efficacy of psychopharmacological agents and psychological or behavioral approaches has been established for serveral of the functional esophageal disorders. As gastroesophageal reflux disease overlaps in presentation with most of these disorders and because symptoms are at least partially provoked by acid reflux events in many patients, antireflux therapy also plays an important role both in diagnosis and management. Further understanding of the fundamental mechanisms responsible for symptoms is a priority for future research efforts, as is the consideration of treatment outcome in a broader sense than reduction in esophageal symptoms alone. Likewise, the value of inclusive rather than restrictive diagnostic criteria that encompass other gastrointestinal and non-gastrointestinal symptoms should be examined to improve the accuracy of symptom-based criteria and reduce the dependence on objective testing.???Keywords: globus; rumination; chest pain; esophageal motility disorders; esophageal spasm; gastroesophageal reflux disease; Rome II PMID:10457042

Clouse, R; Richter, J; Heading, R; Janssens, J; Wilson, J

1999-01-01

372

Choreographing Patterns and Functions  

ERIC Educational Resources Information Center

In this article, the authors begin with a description of an algebraic dance--the translation of composite linear growing patterns into choreographed movement--which was the last component of a research-based instructional unit that focused on fostering an understanding of linear functional rules through geometric growing patterns and…

Hawes, Zachary; Moss, Joan; Finch, Heather; Katz, Jacques

2012-01-01

373

MODELING FUNCTIONAL LANDSCAPE CONNECTIVITY  

Microsoft Academic Search

A significant challenge for conservation science is to understand the needs of wide-ranging species during the design of nature reserves. Although numerous GIS methods exist to analyze patch composition and structure, few methods readily allow a user to incorporate species behavior and scaling. Here I describe a general approach that allows functional properties of organisms and processes to be modeled

David M. Theobald

374

Process for functionalizing alkanes  

DOEpatents

Process for functionalizing saturated hydrocarbons comprises: (a) reacting said saturated hydrocarbons of the formula: R[sub 1]H wherein H represents a hydrogen atom; and R[sub 1] represents a saturated hydrocarbon radical, with a metal complex of the formula: CpRh[P(R[sub 2])[sub 3

Bergman, R.G.; Janowicz, A.H.; Periana, R.A.

1988-05-24

375

Movement with Functions  

NSDL National Science Digital Library

"These three investigations use movement to reinforce the concepts of linear functions and systems of equations. Multiple representations are used throughout, along with tools such as motion detectors and remote-controlled cars. Students explore how position, speed, and varying motion are reflected in graphs, tables, and algebraic equations." from NCTM Illuminations.

Illuminations National Council of Teachers of Mathematics

2009-12-04

376

Functions Defined by Data  

NSDL National Science Digital Library

Created by Lawrence Moore and David Smith for the Connected Curriculum Project, the purpose of this module is to carry out an exploration of functions defined by data; to learn about data entry and plotting operations. This is one lesson in a much larger set of learning modules hosted by Duke University.

Moore, Lawrence C.

377

December 2013 Functional MRI  

E-print Network

BENG-280A December 2013 Functional MRI Richard B. Buxton rbuxton@ucsd.edu Cerebral Blood Flow cerebral blood volume 0.05 ml/ml tissue +10% CMRGlc cereb. metb. rate of Glucose 0.3 µmol/ml tissue-min +25 of the redistribution of blood in his system. ..." William James (Principles of Psychology, 1890) Mosso's experiment

Liu, Thomas T.

378

Functions Defined by Data  

NSDL National Science Digital Library

Created by Lang Moore and David Smith for the Connected Curriculum Project, this module focuses on the ability to carry out an exploration of functions defined by data; to learn about data entry and plotting operations. This is one of a much larger set of learning modules hosted by Duke University.

Moore, Lang

379

Conjugate flow action functionals  

NASA Astrophysics Data System (ADS)

We present a new general framework to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations relative to a diffeomorphic flow of curvilinear coordinates which is assumed to be functionally dependent on the solution field. Such flow, which will be called the conjugate flow, evolves in space and time similarly to a physical fluid flow of classical mechanics and it can be selected in order to symmetrize the Gâteaux derivative of the field equations with respect to suitable local bilinear forms. This is equivalent to requiring that the governing equations of the field theory can be derived from a principle of stationary action on a Lie group manifold. By using a general operator framework, we obtain the determining equations of such manifold and the corresponding conjugate flow action functional. In particular, we study scalar and vector field theories governed by second-order nonlinear partial differential equations. The identification of transformation groups leaving the conjugate flow action functional invariant could lead to the discovery of new conservation laws in fluid dynamics and other disciplines.

Venturi, Daniele

2013-11-01

380

Muscle function loss  

MedlinePLUS

... muscle doesn't work or move normally. The medical term for complete loss of muscle function is paralysis. ... over the eye while you are asleep. Long-term immobility can cause ... , a condition in which a muscle becomes permanently shortened.

381

The Black Body Function.  

ERIC Educational Resources Information Center

Discusses using black body function for radiative heat transfer, which can be used in a real-life application in a number of different topics in A-level and first-year undergraduate mathematical methods courses such as differentiation, solving nonlinear equations, and integration by substitution. (ASK)

Lawson, D. A.

1998-01-01

382

Conjugate flow action functionals  

SciTech Connect

We present a new general framework to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations relative to a diffeomorphic flow of curvilinear coordinates which is assumed to be functionally dependent on the solution field. Such flow, which will be called the conjugate flow, evolves in space and time similarly to a physical fluid flow of classical mechanics and it can be selected in order to symmetrize the Gâteaux derivative of the field equations with respect to suitable local bilinear forms. This is equivalent to requiring that the governing equations of the field theory can be derived from a principle of stationary action on a Lie group manifold. By using a general operator framework, we obtain the determining equations of such manifold and the corresponding conjugate flow action functional. In particular, we study scalar and vector field theories governed by second-order nonlinear partial differential equations. The identification of transformation groups leaving the conjugate flow action functional invariant could lead to the discovery of new conservation laws in fluid dynamics and other disciplines.

Venturi, Daniele, E-mail: daniele-venturi@brown.edu [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)] [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)

2013-11-15

383

Statistical Decision Functions  

Microsoft Academic Search

The foundations of a general theory of statistical decision functions, including the classical non-sequential case as well as the sequential case, was discussed by the author in a previous publication [3]. Several assumptions made in [3] appear, however, to be unnecessarily restrictive (see conditions 1-7, pp. 297 in [3]). These assumptions, moreover, are not always fulfilled for statistical problems in

Abraham Wald

1949-01-01

384

Generalized Density Functional Theory  

Microsoft Academic Search

Positionally dependent and positionally independent weighted density approximations of classical density functional theories are each shown to represent limits of a more general approach. The resulting flexibility is used to improve on the results obtained for inhomogeneous systems, the hard-sphere crystal being given as an example. Physical limitations of such mappings are inherent and are shown to arise from the

A. Khein; N. W. Ashcroft

1997-01-01

385

Transglutaminase Function in Epidermis  

Microsoft Academic Search

Surface epithelial cells, such as the epidermal keratinocyte, undergo a process of terminal cell differentiation that results in the construction of a multilayered epithelium. This epithelium functions to protect the organism from the environment. Transglutaminases, enzymes that catalyze the formation of isopeptide protein-protein cross-links, are key enzymes involved in the construction of this structure. This brief review will focus on

Richard L. Eckert; Michael T. Sturniolo; Ann-Marie Broome; Monica Ruse; Ellen A. Rorke

2005-01-01

386

Two Variable Function Pump  

NSDL National Science Digital Library

Enter two complex numbers (z and c) as ordered pairs of real numbers, then click a button to iterate step by step. The iterates are graphed in the x-y plane and printed out in table form. This is an introduction to the idea of prisoners/escapees in iterated functions and the calculation of fractal Julia sets.

387

Smoothing by spline functions  

Microsoft Academic Search

During the last years, spline functions have found widespread application, mainly for the purpose of interpolation []. However, there may be a demand to replace strict interpolation by some kind of smoothing. Usually, such a situation occurs if the values of the ordinates are given only approximately, for example if they stem from experimental data. In the case in which,

Christian H. Reinsch

1967-01-01

388

Introduction to Green's Functions  

NSDL National Science Digital Library

The tutorial introducing students to Green’s functions was first developed by Professor John Berger of the Colorado School of Mines. That tutorial has been expanded and updated by Professor Ernian Pan and Sandra Djurkovic of the Civil Engineering and the Mathematics Departments of the University of Akron. The zip file contains an html file.

Pan, Ernian

2003-02-07

389

NONSTANDARD TRENDS IN FUNCTIONAL ANALYSIS  

E-print Network

NONSTANDARD TRENDS IN FUNCTIONAL ANALYSIS A. G. Kusraev (Vladikavkaz), S. S. Kutateladze. S. Kutateladze (Novosibirsk) NONSTANDARD TRENDS IN FUNCTIONAL ANALYSIS #12;Boolean Valued Analysis (Vladikavkaz), S. S. Kutateladze (Novosibirsk) NONSTANDARD TRENDS IN FUNCTIONAL ANALYSIS #12;Boolean Valued

Kutateladze, Semen Samsonovich

390

Multitaper S Receiver Functions  

NASA Astrophysics Data System (ADS)

We have adapted the multiple-taper correlation (MTC) P receiver-function algorithm of Park and Levin (2000) (see also Helffrich (2006)) to estimate S-to-P converted phases from buried interfaces within Earth. Theory predicts that the amplitude of the Sp converted phase varies sinusoidally with back azimuth in the presence of anisotropy or dipping interfaces, but this behavior is rarely explored, despite the fact that some structural models for the lithosphere-asthenosphere boundary, a favorite target of S receiver functions, predict sharp transitions in anisotropy as well as isotropic seismic wavespeed. The S receiver function can also estimate shear-wave birefringence from broadband SKS or other SV-polarized waves, following the original frequency-domain formulas of Silver and Chan (1991). We use the statistical properties of the MTC algorithm to estimate uncertainties on the S receiver functions in the frequency domain, which aids in forming stacks, allowing low-quality data, in which the coherence between SV, SH and P polarization directions is poor, to be downweighted in an automated procedure. We test our algorithm on a familiar data set from IRIS GSN station RAYN within the stable-craton Arabian peninsula. Our previous work at RAYN found simple SKS birefringence and narrow zones of anisotropic rocks at depths ~70-100 km (Levin and Park, 2000), targets that are ideally suited to evaluate the performance of an S receiver-function algorithm. Helffrich, G., 2006. Extended-time multitaper frequency domain cross-correlation receiver-function estimation, Bull. Seism. Soc. Am., 98, 344-347, doi: 10.1785/0120050098. Levin, V., Park, J., 2000. Shear zones in the Proterozoic lithosphere of the Arabian Shield and the nature of the Hales discontinuity. Tectonophysics 323, 131-148. Park, J., & Levin, V., 2000. Receiver functions from multiple-taper spectral correlation estimates, Bull. Seism. Soc. Am., 90, 1507-1520. Silver, P.G. & Chan, W.W., 1991. Shear-wave splitting and subcontinental mantle deformation, J. Geophys. Res., 96, 16 429-16 454.

Park, J. J.; Levin, V. L.

2011-12-01

391

Pulmonary function in space  

NASA Technical Reports Server (NTRS)

The lung is exquisitely sensitive to gravity, and so it is of interest to know how its function is altered in the weightlessness of space. Studies on National Aeronautics and Space Administration (NASA) Spacelabs during the last 4 years have provided the first comprehensive data on the extensive changes in pulmonary function that occur in sustained microgravity. Measurements of pulmonary function were made on astronauts during space shuttle flights lasting 9 and 14 days and were compared with extensive ground-based measurements before and after the flights. Compared with preflight measurements, cardiac output increased by 18% during space flight, and stroke volume increased by 46%. Paradoxically, the increase in stroke volume occurred in the face of reductions in central venous pressure and circulating blood volume. Diffusing capacity increased by 28%, and the increase in the diffusing capacity of the alveolar membrane was unexpectedly large based on findings in normal gravity. The change in the alveolar membrane may reflect the effects of uniform filling of the pulmonary capillary bed. Distributions of blood flow and ventilation throughout the lung were more uniform in space, but some unevenness remained, indicating the importance of nongravitational factors. A surprising finding was that airway closing volume was approximately the same in microgravity and in normal gravity, emphasizing the importance of mechanical properties of the airways in determining whether they close. Residual volume was unexpectedly reduced by 18% in microgravity, possibly because of uniform alveolar expansion. The findings indicate that pulmonary function is greatly altered in microgravity, but none of the changes observed so far will apparently limit long-term space flight. In addition, the data help to clarify how gravity affects pulmonary function in the normal gravity environment on Earth.

West, J. B.; Elliott, A. R.; Guy, H. J.; Prisk, G. K.

1997-01-01

392

Engineering living functional materials.  

PubMed

Natural materials, such as bone, integrate living cells composed of organic molecules together with inorganic components. This enables combinations of functionalities, such as mechanical strength and the ability to regenerate and remodel, which are not present in existing synthetic materials. Taking a cue from nature, we propose that engineered 'living functional materials' and 'living materials synthesis platforms' that incorporate both living systems and inorganic components could transform the performance and the manufacturing of materials. As a proof-of-concept, we recently demonstrated that synthetic gene circuits in Escherichia coli enabled biofilms to be both a functional material in its own right and a materials-synthesis platform. To demonstrate the former, we engineered E. coli biofilms into a chemical-inducer-responsive electrical switch. To demonstrate the latter, we engineered E. coli biofilms to dynamically organize biotic-abiotic materials across multiple length scales, template gold nanorods, gold nanowires, and metal/semiconductor heterostructures, and synthesize semiconductor nanoparticles (Chen, A. Y. et al. (2014) Synthesis and patterning of tunable multiscale materials with engineered cells. Nat. Mater. 13, 515-523.). Thus, tools from synthetic biology, such as those for artificial gene regulation, can be used to engineer the spatiotemporal characteristics of living systems and to interface living systems with inorganic materials. Such hybrids can possess novel properties enabled by living cells while retaining desirable functionalities of inorganic systems. These systems, as living functional materials and as living materials foundries, would provide a radically different paradigm of materials performance and synthesis-materials possessing multifunctional, self-healing, adaptable, and evolvable properties that are created and organized in a distributed, bottom-up, autonomously assembled, and environmentally sustainable manner. PMID:25592034

Chen, Allen Y; Zhong, Chao; Lu, Timothy K

2015-01-16

393

Functional relations for the density-functional exchange and correlation functionals connecting functionals at three densities  

NASA Astrophysics Data System (ADS)

It is shown that the density-functional-theory exchange and correlation functionals satisfy 0=?Ehx[?N]+2Ec?[?N]-?Ehx[?N-1?]-2Ec?[?N-1?]+2?d3r'[?N-10(r)-?N-1?(r)]v0([?N];r)+?d3r'[?N-10(r)-?N-1?(r)]r·?v0([?N];r)+?d3r'?N(r)r·?vc?([?N];r)-?d3r'?N-1?(r)r·?vc?([?N-1?];r)-?d3r'f?(r)r·?vhxc?([?N];r)-2?d3r'f?(r)vhxc?([?N];r). In the derivation of this equation the adiabatic connection formulation is used, where the ground-state density of an N-electron system ?N is kept constant independent of the electron-electron coupling strength ?. Here Ehx[?] is the Hartree plus exchange energy, Ec?[?] is the correlation energy, vhxc?[?] is the Hartree plus exchange-correlation potential, vc[?] is the correlation potential, and v0[?]is the Kohn-Sham potential. The charge densities ?N and ?N-1? are the N- and (N-1)-electron ground-state densities of the same Hamiltonian at electron-electron coupling strength ?. f?(r)=?N(r)-?N-1?(r) is the Fukui function. This equation can be useful in testing the internal self-consistency of approximations to the exchange and correlation functionals. As an example the identity is tested on the analytical Hooke's atom charge density for some frequently used approximate functionals.

Joubert, Daniel P.

2012-03-01

394

The Relationships between Weight Functions, Geometric Functions,and Compliance Functions in Linear Elastic Fracture Mechanics  

SciTech Connect

Linear elastic fracture mechanics is widely used in industry because it established simple and explicit relationships between the permissible loading conditions and the critical crack size that is allowed in a structure. Stress intensity factors are the above-mentioned functional expressions that relate load with crack size through geometric functions or weight functions. Compliance functions are to determine the crack/flaw size in a structure when optical inspection is inconvenient. As a result, geometric functions, weight functions and compliance functions have been intensively studied to determine the stress intensity factor expressions for different geometries. However, the relations between these functions have received less attention. This work is therefore to investigate the intrinsic relationships between these functions. Theoretical derivation was carried out and the results were verified on single-edge cracked plate under tension and bending. It is found out that the geometric function is essentially the non-dimensional weight function at the loading point. The compliance function is composed of two parts: a varying part due to crack extension and a constant part from the intact structure if no crack exists. The derivative of the compliance function at any location is the product of the geometric function and the weight function at the evaluation point. Inversely, the compliance function can be acquired by the integration of the product of the geometric function and the weight function with respect to the crack size. The integral constant is just the unchanging compliance from the intact structure. Consequently, a special application of the relations is to obtain the compliance functions along a crack once the geometric function and weight functions are known. Any of the three special functions can be derived once the other two functions are known. These relations may greatly simplify the numerical process in obtaining either geometric functions, weight functions or compliance functions for new test geometries.

Yuan, Rong

2007-02-06

395

Dirac Delta Function 1 Definition  

E-print Network

Dirac Delta Function 1 Definition Dirac's delta function is defined by the following property (t of the delta function is the following relation dtf(t)(t) = f(0) (5) for any function f(t). This is easy to see to dtf(t)(t - t0) = f(t0). (6) Mathematically, the delta function is not a function, because it is too

Murayama, Hitoshi

396

Functional Brain Imaging  

PubMed Central

Executive Summary Objective The objective of this analysis is to review a spectrum of functional brain imaging technologies to identify whether there are any imaging modalities that are more effective than others for various brain pathology conditions. This evidence-based analysis reviews magnetoencephalography (MEG), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), and functional magnetic resonance imaging (fMRI) for the diagnosis or surgical management of the following conditions: Alzheimer’s disease (AD), brain tumours, epilepsy, multiple sclerosis (MS), and Parkinson’s disease (PD). Clinical Need: Target Population and Condition Alzheimer’s disease is a progressive, degenerative, neurologic condition characterized by cognitive impairment and memory loss. The Canadian Study on Health and Aging estimated that there will be 97,000 incident cases (about 60,000 women) of dementia (including AD) in Canada in 2006. In Ontario, there will be an estimated 950 new cases and 580 deaths due to brain cancer in 2006. Treatments for brain tumours include surgery and radiation therapy. However, one of the limitations of radiation therapy is that it damages tissue though necrosis and scarring. Computed tomography (CT) and magnetic resonance imaging (MRI) may not distinguish between radiation effects and resistant tissue, creating a potential role for functional brain imaging. Epilepsy is a chronic disorder that provokes repetitive seizures. In Ontario, the rate of epilepsy is estimated to be 5 cases per 1,000 people. Most people with epilepsy are effectively managed with drug therapy; but about 50% do not respond to drug therapy. Surgical resection of the seizure foci may be considered in these patients, and functional brain imaging may play a role in localizing the seizure foci. Multiple sclerosis is a progressive, inflammatory, demyelinating disease of the central nervous system (CNS). The cause of MS is unknown; however, it is thought to be due to a combination of etiologies, including genetic and environmental components. The prevalence of MS in Canada is 240 cases per 100,000 people. Parkinson’s disease is the most prevalent movement disorder; it affects an estimated 100,000 Canadians. Currently, the standard for measuring disease progression is through the use of scales, which are subjective measures of disease progression. Functional brain imaging may provide an objective measure of disease progression, differentiation between parkinsonian syndromes, and response to therapy. The Technology Being Reviewed Functional Brain Imaging Functional brain imaging technologies measure blood flow and metabolism. The results of these tests are often used in conjunction with structural imaging (e.g., MRI or CT). Positron emission tomography and MRS identify abnormalities in brain tissues. The former measures abnormalities through uptake of radiotracers in the brain, while the latter measures chemical shifts in metabolite ratios to identify abnormalities. The potential role of functional MRI (fMRI) is to identify the areas of the brain responsible for language, sensory and motor function (sensorimotor cortex), rather than identifying abnormalities in tissues. Magnetoencephalography measures magnetic fields of the electric currents in the brain, identifying aberrant activity. Magnetoencephalography may have the potential to localize seizure foci and to identify the sensorimotor cortex, visual cortex and auditory cortex. In terms of regulatory status, MEG and PET are licensed by Health Canada. Both MRS and fMRI use a MRI platform; thus, they do not have a separate licence from Health Canada. The radiotracers used in PET scanning are not licensed by Health Canada for general use but can be used through a Clinical Trials Application. Review Strategy The literature published up to September 2006 was searched in the following databases: MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Cochrane Database of Systematic Reviews, CENTRAL, and International Network of Agencies for H

2006-01-01

397

Functional Performance Evaluation  

NASA Technical Reports Server (NTRS)

The Extended Duration Orbiter Medical Project (EDOMP) was established to address specific issues associated with optimizing the ability of crews to complete mission tasks deemed essential to entry, landing, and egress for spaceflights lasting up to 16 days. The main objectives of this functional performance evaluation were to investigate the physiological effects of long-duration spaceflight on skeletal muscle strength and endurance, as well as aerobic capacity and orthostatic function. Long-duration exposure to a microgravity environment may produce physiological alterations that affect crew ability to complete critical tasks such as extravehicular activity (EVA), intravehicular activity (IVA), and nominal or emergency egress. Ultimately, this information will be used to develop and verify countermeasures. The answers to three specific functional performance questions were sought: (1) What are the performance decrements resulting from missions of varying durations? (2) What are the physical requirements for successful entry, landing, and emergency egress from the Shuttle? and (3) What combination of preflight fitness training and in-flight countermeasures will minimize in-flight muscle performance decrements? To answer these questions, the Exercise Countermeasures Project looked at physiological changes associated with muscle degradation as well as orthostatic intolerance. A means of ensuring motor coordination was necessary to maintain proficiency in piloting skills, EVA, and IVA tasks. In addition, it was necessary to maintain musculoskeletal strength and function to meet the rigors associated with moderate altitude bailout and with nominal or emergency egress from the landed Orbiter. Eight investigations, referred to as Detailed Supplementary Objectives (DSOs) 475, 476, 477, 606, 608, 617, 618, and 624, were conducted to study muscle degradation and the effects of exercise on exercise capacity and orthostatic function (Table 3-1). This chapter is divided into three parts. Part 1 describes specific findings from studies of muscle strength, endurance, fiber size, and volume. Part 2 describes results from studies of how in-flight exercise affects postflight exercise capacity and orthostatic function. Part 3 focuses on the development of new noninvasive methods for assessing body composition in astronauts and how those methods can be used to correlate measures of exercise performance and changes in body composition.

Greenisen, Michael C.; Hayes, Judith C.; Siconolfi, Steven F.; Moore, Alan D.

1999-01-01

398

Generating Functions 10.1 Generating Functions for Discrete Distribu-  

E-print Network

;368 CHAPTER 10. GENERATING FUNCTIONS Here µ1 = g (0) = pet (1 - qet)2 t=0 = 1 p , µ2 = g (0) = pet + pqe2t (1Chapter 10 Generating Functions 10.1 Generating Functions for Discrete Distribu- tions So far we the distribution function of that variable. Now we shall see that the mean and variance do not contain all

Rapaport, Iván

399

Elements of Functional Neuroimaging 1 ELEMENTS OF FUNCTIONAL NEUROIMAGING  

E-print Network

tomography (PET) and functional Magnetic Resonance Imaging (fMRI) from 1985 to 2004. A recent surgeElements of Functional Neuroimaging 1 ELEMENTS OF FUNCTIONAL NEUROIMAGING Tor D. Wager1* Luis. (2007). Elements of functional neuroimaging. In J. T. Cacioppo, L. G. Tassinary & G. G. Berntson (Eds

Jonides, John

400

Relating the Implementation Techniques of Functional and Functional Logic Languages  

Microsoft Academic Search

Functional logic languages are declarative programming languages that integratethe programming paradigms of functional and logic languages within a single framework.They are extensions of functional languages with principles derived from logicprogramming. Narrowing, the evaluation mechanism of functional logic languages,can be defined as a generalization of reduction, the evaluation mechanism of purelyfunctional languages. The unidirectional pattern matching, which is used for parameter...

Rita Loogen; RWTH Aachen

1993-01-01

401

Functionalization of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H2 or F2 or CnHm) is irradiated to provide a cold plasma of selected target species particles, such as atomic H or F, in a first chamber. The target species particles are d irected toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target species particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec. *Discrimination against non-target species is provided by (i) use of a target species having a lifetime that is much greater than a lifetime of a non-target species and/or (2) use of an applied magnetic field to discriminate between charged particle trajectories for target species and for non-target species.

Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)

2009-01-01

402

Functional magnetic microspheres  

NASA Technical Reports Server (NTRS)

Functional magnetic particles are formed by dissolving a mucopolysaccharide such as chitosan in acidified aqueous solution containing a mixture of ferrous chloride and ferric chloride. As the pH of the solution is raised magnetite is formed in situ in the solution by raising the pH. The dissolved chitosan is a polyelectrolyte and forms micelles surrounding the granules at pH of 8-9. The chitosan precipitates on the granules to form microspheres containing the magnetic granules. On addition of the microspheres to waste aqueous streams containing dissolved ions, the hydroxyl and amine functionality of the chitosan forms chelates binding heavy metal cations such as lead, copper, and mercury and the chelates in turn bind anions such as nitrate, fluoride, phosphate and borate.

Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Landel, Robert F. (Inventor)

1981-01-01

403

Macrophage function in atherosclerosis  

PubMed Central

Cation channels of the Transient Receptor Potential Canonical (TRPC) group, which belong to the larger TRP superfamily of channel proteins, are critical players in cardiovascular disease. Recent studies underscored a role of TRPC3 in macrophage survival and efferocytosis, two critical events in atherosclerosis lesion development. Also, other members of the TRP channel superfamily are found expressed in monocytes/macrophages, where they participate in processes that might be of significance to atherogenesis. These observations set a framework for future studies aimed at defining the ultimate functions not only of TRPC3, but probably other TRP channels, in macrophage biology. The purpose of this manuscript is to provide a timely revision of existing evidence on the role of members of the TRP channel superfamily, in particular TRPCs, in macrophages and discuss it in the context of the macrophage’s function in atherogenesis. PMID:22909953

Tano, Jean-Yves K.; Lee, Robert H.; Vazquez, Guillermo

2012-01-01

404

Roughness and function  

NASA Astrophysics Data System (ADS)

A function map is used to locate applications of roughness in separation-velocity space. The importance of roughness in contact mechanics is demonstrated and versions of the plasticity index are introduced and compared. Case studies of roughness and function are presented from tribology and the life sciences. Tribological examples are taken from the automotive industry and include the manufacture of vehicle bodies, and drive train tribology, particularly cylinder liner, cam and gearbox friction and wear. From the life sciences, problems of prosthetic fixation and tribology are shown to depend on roughness. The interaction of haptics and surface finish is described and illustrated. A number of other areas of application are listed. Finally the likely future importance of structured surfaces is discussed.

Thomas, T. R.

2014-01-01

405

Process for functionalizing alkanes  

DOEpatents

Process for functionalizing saturated hydrocarbons selectively in the terminal position comprises: (a) reacting said saturated hydrocarbons with a metal complex CpRhPMe/sub 3/H/sub 2/ in the presence of ultraviolet radiation at -60/sup 0/ to -17/sup 0/C to form a hydridoalkyl complex CpRhPMe/sub 3/RH; (b) reacting said hydridoalkyl complex with a haloform CHX/sub 3/ at -60/sup 0/ to -17/sup 0/C to form the corresponding haloalkyl complex of step (a) CpRhPMe/sub 3/RX; and (c) reacting said haloalkyl complex with halogen -60 to 25/sup 0/C to form a functional haloalkyl compound.

Bergman, R.G.; Janowicz, A.H.; Periana-Pillai, R.A.

1984-06-12

406

Nuclear functions of prefoldin  

PubMed Central

Prefoldin is a cochaperone, present in all eukaryotes, that cooperates with the chaperonin CCT. It is known mainly for its functional relevance in the cytoplasmic folding of actin and tubulin monomers during cytoskeleton assembly. However, both canonical and prefoldin-like subunits of this heterohexameric complex have also been found in the nucleus, and are functionally connected with nuclear processes in yeast and metazoa. Plant prefoldin has also been detected in the nucleus and physically associated with a gene regulator. In this review, we summarize the information available on the involvement of prefoldin in nuclear phenomena, place special emphasis on gene transcription, and discuss the possibility of a global coordination between gene regulation and cytoplasmic dynamics mediated by prefoldin. PMID:25008233

Millán-Zambrano, Gonzalo; Chávez, Sebastián

2014-01-01

407

[Functional venous explorations].  

PubMed

The methods for exploring venous function globally are presented first. These methods include venous pressure and plethysmography for which the methods using a garrot are separated from those using air volumetry which give reliable physiological and reproducible results. The Nachev method, the thermometry, the thermography and isotope clearances are also reviewed since they have been important in the development of exploration of venous function. The methods giving morphological or segmentary data are then presented in historical order: phlebography (completed by tomodensitography and nuclear magnetic resonance), then ultrasonography with Doppler, echography and duplex and colour techniques. Finally promising methods for the future including oxygen partial pressures, laser-Doppler, capillaroscopy and venous endoscopy are discussed. For each method, there is a description of the technique, a presentation of the measured parameters and their reliability, the signification of the measurement and its clinical use. Finally, each method is discussed in the context of concrete clinical situations with a schema for management of diagnosis. PMID:8177873

Mollard, J M

1994-02-10

408

Functional Biomimetic Architectures  

NASA Astrophysics Data System (ADS)

N-substituted glycine oligomers, or 'peptoids,' are a class of sequence--specific foldamers composed of tertiary amide linkages, engendering proteolytic stability and enhanced cellular permeability. Peptoids are notable for their facile synthesis, sequence diversity, and ability to fold into distinct secondary structures. In an effort to establish new functional peptoid architectures, we utilize the copper-catalyzed azide-alkyne [3+2] cycloaddition (CuAAC) reaction to generate peptidomimetic assemblies bearing bioactive ligands that specifically target and modulate Androgen Receptor (AR) activity, a major therapeutic target for prostate cancer. Additionally, we explore chemical ligation protocols to generate semi-synthetic hybrid biomacromolecules capable of exhibiting novel structures and functions not accessible to fully biosynthesized proteins.

Levine, Paul M.

409

Semiconductor photonic functional devices  

Microsoft Academic Search

Recent advances in semiconductor photonic functional devices based on the nonlinearities of laser diodes (LDs) are reviewed. Because the current research is driven primarily by the needs of optical fiber communications systems, most devices are made of InGaAsP and operate at wavelengths of between 1.3 and 1.55 ?m, the wavelength window in which optical fibers have their most favorable properties.

H. Kawaguchi

1991-01-01

410

CORDIC: Elementary Function Computation  

Microsoft Academic Search

Many of us who teach calculus and mathematical topics that use calculus have taken for granted that hand-held calculators use Taylor series or a variant to compute transcendental functions. Thus, it was a surprise to learn that this was not the case. The CORDIC method (Coordinate Rotation Digital Computer) was developed by Jack Volder (6) in the late 1950's. Hewlett-Packard

Neil Eklund

411

Infant Pulmonary Function Testing  

PubMed Central

Infant pulmonary function testing has evolved from a research technique into a diagnostic tool. As such, new current procedural terminology (CPT) codes have been created and are available for use as of January 1, 2010. The technology now available has a range of applications. Through a series of vignettes, this article illustrates the methodology of the tests, some of their applications, and how to code and bill for the procedures. PMID:21540218

Davis, Stephanie D.

2011-01-01

412

Intracellular functions of galectins  

Microsoft Academic Search

Many galectin family members are detected primarily intracellularly in most of the systems studied, although certain members can be found both inside and outside of cells. Specific functions that are consistent with their intracellular localization have now been documented for some of the galectins. Galectin-1 and -3 have been identified as redundant pre-mRNA splicing factors. Galectin-3, -7, and -12 have

Fu-Tong Liu; Ronald J Patterson; John L Wang

2002-01-01

413

Functionalization of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

These project will explore the functionalization of carbon nanotubes via the formation of molecular complexes with perylene diimide based systems. It is anticipated that these complexes would be soluble in organic solvent and enable the homogenous dispersion of carbon nanotubes in polymer films. Molecular complexes will be prepared and characterized using standard spectroscopic and thermal analytical techniques. Polymer films will be prepared with these complexes and their properties (electrical and thermal conductivity, mechanical properties, stability) evaluated.

Webber, Stephen E.

2003-01-01

414

Heart Function and Development  

NSDL National Science Digital Library

In this module, developed as part of Cornell's Learning Initiative in Medicine and Bioengineering (CLIMB), students will learn the basic process of heart development, along with the anatomy and function of the heart. Students will also learn about embryonic development and be introduced to observational tools used by biomedical researchers. This module includes a teacher's guide with learning objectives outlined, classroom activities, and supporting image files. CLIMB is part of the NSF GK-12 program.

CLIMB: Cornell's Learning Initiative in Medicine and Bioengineering

415

Insomnia and daytime functioning  

Microsoft Academic Search

Results from the present review challenge the assumption that daytime functioning deficits are associated with insomnia. Objectively-measured daytime sleepiness is not elevated in people with insomnia, and most cognitive\\/psychomotor tasks do not indicate deficits in people with insomnia. In contrast, a number of studies have found that people with insomnia self-report daytime symptoms such as elevated fatigue, mood disturbance and

Brant W. Riedel; Kenneth L. Lichstein

2000-01-01

416

Barbie Bungee (linear functions)  

NSDL National Science Digital Library

The consideration of cord length is very important in a bungee jump—too short, and the jumper doesn't get much of a thrill; too long, and ouch! In this lesson, students model a bungee jump using a Barbie® doll and rubber bands. The distance to which the doll will fall is directly proportional to the number of rubber bands, so this context is used to examine linear functions.

NCTM Illuminations

2009-02-12

417

Recursive Functions in Iris  

Microsoft Academic Search

A complete and efficient implementation of linear, one-side recursive queries in Iris, an object-oriented database management system, is described. It is shown that recursion can be easily and efficiently added to a large class of existing database management systems. A B-tree type access path called the B++ tree that has been implemented to support the computation of recursive functions in

Philippe De Smedt; Stefano Ceri; Marie-anne Neimat; Ming-chien Shan; Rafi Ahmed

1993-01-01

418

Executive Functioning in Schizophrenia  

PubMed Central

The executive function (EF) is a set of abilities, which allows us to invoke voluntary control of our behavioral responses. These functions enable human beings to develop and carry out plans, make up analogies, obey social rules, solve problems, adapt to unexpected circumstances, do many tasks simultaneously, and locate episodes in time and place. EF includes divided attention and sustained attention, working memory (WM), set-shifting, flexibility, planning, and the regulation of goal directed behavior and can be defined as a brain function underlying the human faculty to act or think not only in reaction to external events but also in relation with internal goals and states. EF is mostly associated with dorsolateral prefrontal cortex (PFC). Besides EF, PFC is involved in self-regulation of behavior, i.e., the ability to regulate behavior according to internal goals and constraints, particularly in less structured situations. Self-regulation of behavior is subtended by ventral medial/orbital PFC. Impairment of EF is one of the most commonly observed deficits in schizophrenia through the various disease stages. Impairment in tasks measuring conceptualization, planning, cognitive flexibility, verbal fluency, ability to solve complex problems, and WM occur in schizophrenia. Disorders detected by executive tests are consistent with evidence from functional neuroimaging, which have shown PFC dysfunction in patients while performing these kinds of tasks. Schizophrenics also exhibit deficit in odor identifying, decision-making, and self-regulation of behavior suggesting dysfunction of the orbital PFC. However, impairment in executive tests is explained by dysfunction of prefronto-striato-thalamic, prefronto-parietal, and prefronto-temporal neural networks mainly. Disorders in EFs may be considered central facts with respect to schizophrenia and it has been suggested that negative symptoms may be explained by that executive dysfunction. PMID:23805107

Orellana, Gricel; Slachevsky, Andrea

2013-01-01

419

Functional ingredients from microalgae.  

PubMed

A wide variety of natural sources are under investigation to evaluate their possible use for new functional ingredient formulation. Some records attested the traditional and ancient use of wild harvested microalgae as human food but their cultivation for different purposes started about 40 years ago. The most popular species are Arthrospira (traditional name, Spirulina), Chlorella spp., Dunaliella spp. and Haematococcus spp. Microalgae provide a bewildering array of opportunities to develop healthier food products using innovative approaches and a number of different strategies. Compared to other natural sources of bioactive ingredients, microalgae have many advantages such as their huge biodiversity, the possibility to grow in arid land and with limited fresh water consumption and the flexibility of their metabolism, which could be adapted to produce specific molecules. All these factors led to very sustainable production making microalgae eligible as one of the most promising foods for the future, particularly as source of proteins, lipids and phytochemicals. In this work, a revision of the knowledge about the use of microalgae as food and as a source of functional ingredients has been performed. The most interesting results in the field are presented and commented upon, focusing on the different species of microalgae and the activity of the nutritionally relevant compounds. A summary of the health effects obtained together with pros and cons in the adoption of this natural source as functional food ingredients is also proposed. PMID:24957182

Buono, Silvia; Langellotti, Antonio Luca; Martello, Anna; Rinna, Francesca; Fogliano, Vincenzo

2014-08-01

420

Vitamin D & endothelial function  

PubMed Central

There is increasing interest in the extra-skeletal roles of vitamin D for health and well-being. Poor vitamin D status has been associated with obesity, cardiovascular disease, type 2 diabetes and mental health. Endothelial dysfunction may underscore insulin resistance and hence predispose to both cardiovascular disease (CVD) and type 2 diabetes. The objective of this review was to gain an appreciation of the recent causative evidence linking vitamin D and endothelial function. The PubMed database was searched from 2009 to date. Key words used were vitamin D, supplementation, systemic inflammation, endothelium, endothelial dysfunction and humans. Selected articles were restricted to the English language and to randomized control trials (RCTs) of vitamin D supplementation with direct measures of endothelial function. Final inclusion was based on a quality rating ? 3, based on the Jadad score. Ten RCTs met these criteria and were summarized for their outcomes. Only two studies showed an improvement in flow mediated dilatation with vitamin D. Three other studies reported decreases in C-reactive protein, platelet activation inhibitor-1, tissue plasminogen activator or B type natriuretic peptide. Recent evidence from good quality RCTs did not support a beneficial effect of vitamin D on vascular reactivity. Future intervention studies may need to target a higher vitamin D status and longer duration to determine whether the vitamin has a regulatory role in endothelial function. PMID:25488441

Alyami, A.; Soares, M.J.; Sherriff, J.L.; Mamo, J.C.

2014-01-01

421

Functions of multivector variables  

E-print Network

As is well known, the common elementary functions defined over the real numbers can be generalized to act not only over the complex number field but also over the skew (non-commuting) field of the quaternions. In this paper, we detail a number of elementary functions extended to act over the skew field of Clifford multivectors, in both two and three dimensions. Complex numbers, quaternions and Cartesian vectors can be described by the various components within a Clifford multivector and from our results we are able to demonstrate new inter-relationships between these algebraic systems. One key relationship that we discover is that a complex number raised to a vector power produces a quaternion thus combining these systems within a single equation. We also find a single formula that produces the square root, amplitude and inverse of a multivector over one, two and three dimensions. Finally, comparing the functions over different dimension we observe that $ C\\ell \\left (\\Re^3 \\right) $ provides a particularly versatile algebraic framework.

James M. Chappell; Azhar Iqbal; Lachlan J. Gunn; Derek Abbott

2014-08-26

422

A Generalized Wall Function  

NASA Technical Reports Server (NTRS)

The asymptotic solutions, described by Tennekes and Lumley (1972), for surface flows in a channel, pipe or boundary layer at large Reynolds numbers are revisited. These solutions can be extended to more complex flows such as the flows with various pressure gradients, zero wall stress and rough surfaces, etc. In computational fluid dynamics (CFD), these solutions can be used as the boundary conditions to bridge the near-wall region of turbulent flows so that there is no need to have the fine grids near the wall unless the near-wall flow structures are required to resolve. These solutions are referred to as the wall functions. Furthermore, a generalized and unified law of the wall which is valid for whole surface layer (including viscous sublayer, buffer layer and inertial sublayer) is analytically constructed. The generalized law of the wall shows that the effect of both adverse and favorable pressure gradients on the surface flow is very significant. Such as unified wall function will be useful not only in deriving analytic expressions for surface flow properties but also bringing a great convenience for CFD methods to place accurate boundary conditions at any location away from the wall. The extended wall functions introduced in this paper can be used for complex flows with acceleration, deceleration, separation, recirculation and rough surfaces.

Shih, Tsan-Hsing; Povinelli, Louis A.; Liu, Nan-Suey; Potapczuk, Mark G.; Lumley, J. L.

1999-01-01

423

Functions of Multivector Variables  

PubMed Central

As is well known, the common elementary functions defined over the real numbers can be generalized to act not only over the complex number field but also over the skew (non-commuting) field of the quaternions. In this paper, we detail a number of elementary functions extended to act over the skew field of Clifford multivectors, in both two and three dimensions. Complex numbers, quaternions and Cartesian vectors can be described by the various components within a Clifford multivector and from our results we are able to demonstrate new inter-relationships between these algebraic systems. One key relationship that we discover is that a complex number raised to a vector power produces a quaternion thus combining these systems within a single equation. We also find a single formula that produces the square root, amplitude and inverse of a multivector over one, two and three dimensions. Finally, comparing the functions over different dimension we observe that C?(?3) provides a particularly versatile algebraic framework. PMID:25774689

Chappell, James M.; Iqbal, Azhar; Gunn, Lachlan J.; Abbott, Derek

2015-01-01

424

Carbasugars: Synthesis and Functions  

NASA Astrophysics Data System (ADS)

It is well recognized that glycosidase inhibitors are not only tools to elucidate the mechanism of a living system manipulated by glycoconjugates but also potential clinical drugs and insecticides by inducing the failure of glycoconjugates to perform their function. In this chapter, the syntheses and functions of natural glycosidase inhibitors (cyclophelitol , allosamidine , and trehazoilin ), which possess highly oxygenated and functionalized cyclohexanes or cyclopentanes in their structures and are defined as carbasugars , and the structure and activity relationships (SAR) of their derivatives are described. Also, recently much attention has been focused on neuraminidase inhibitors as anti-influenza drugs since relenza , which was derived from sialic acid, and also, tamiflu , which is the artificial carbasugar designed as a transition state analogue in the hydrolysis pathway of substrates by neuraminidase, were launched in the market. Herein, the medicinal chemistry efforts to discover tamiflu and some efficient syntheses applicable to process chemistry are described. Finally, useful synthetic methodologies for carbasugar formation from sugars are also introduced in this chapter.

Kobayashi, Yoshiyuki

425

Functional studies of eppin.  

PubMed

Our laboratory has characterized EPPIN [epididymal protease inhibitor; SPINLW1] as a novel gene on human chromosome 20q12-13.2, which encodes a cysteine-rich protein of 133 amino acids with a calculated molecular mass of 15.283 kDa, containing both Kunitz-type and WAP (whey acidic protein)-type four-disulfide core consensus sequences. Eppin is secreted by Sertoli cells in the testis and epididymal epithelial cells; it is predominantly a dimer, although multimers often exist, and in its native form eppin is found on the human sperm surface complexed with LTF (lactotransferrin) and clusterin. During ejaculation SEMG (semenogelin) from the seminal vesicles binds to the eppin protein complex, initiating a series of events that define eppin's function. Eppin's functions include (i) modulating PSA (prostate-specific antigen) enzyme activity, (ii) providing antimicrobial protection and (iii) binding SEMG thereby inhibiting sperm motility. As PSA hydrolyses SEMG in the ejaculate coagulum, spermatozoa gain progressive motility. We have demonstrated that eppin is essential for fertility because immunization of male monkeys with recombinant eppin results in complete, but reversible, contraception. To exploit our understanding of eppin's function, we are developing compounds that inhibit eppin-SEMG interaction and mimic anti-eppin, inhibiting sperm motility. These compounds should have potential as a male contraceptive. PMID:21936831

O'Rand, Michael G; Widgren, Esther E; Hamil, Katherine G; Silva, Erick J; Richardson, Richard T

2011-10-01

426

Development of Functional Foods  

PubMed Central

Recent advances in intestinal microbiota research are the background for the appearance of functional foods. Lactic fermentation products are included in the functional foods and classified into 3 groups based on their mechanisms of action: probiotics, prebiotics and biogenics. Probiotics are viable microorganisms, such as lactobacilli and bifidobacteria, that beneficially affect the host by improving the intestinal bacterial balance. Prebiotics are nondigestible food ingredients, such as oligosaccharides and dietary fiber, that beneficially affect the host by selectively stimulating the growth or activities of beneficial intestinal bacteria in the colon and thus improve the health of the hosts. Biogenics are biologically active peptides, including immunopotentiators (biological response modifier: BRM), plant flavonoids, etc. They act directly or indirectly through modulation of intestinal microbiota on the health of the hosts. Thus, functional foods enhance bioregulation such as stresses, appetite and absorption; biodefence, such as immunity and suppression of allergies; prevent diseases, including diarrhea, constipation, cancer, cholesterolemia and diabetes; and suppress aging through immunostimulation as well as suppression of mutagenesis, carcinogenesis, oxidation processes, intestinal putrefaction, and cholesterolemia. PMID:25032085

MITSUOKA, Tomotari

2014-01-01

427

Galaxy cosmological mass function  

NASA Astrophysics Data System (ADS)

Aims: This paper studies the galaxy cosmological mass function (GCMF) in a semi-empirical relativistic approach that uses observational data provided by recent galaxy redshift surveys. Methods: Starting from a previously presented relation between the mass-to-light ratio, the selection function obtained from the luminosity function (LF) data and the luminosity density, the average luminosity L, and the average galactic mass ?g were computed in terms of the redshift. ?g was also alternatively estimated by means of a method that uses the galaxy stellar mass function (GSMF). Comparison of these two forms of deriving the average galactic mass allowed us to infer a possible bias introduced by the selection criteria of the survey. We used the FORS Deep Field galaxy survey sample of 5558 galaxies in the redshift range 0.5 function, but whose fitted parameter values are different from the values found in the literature for the GSMF. Conclusions: This GCMF behavior follows the theoretical predictions from the cold dark matter models in which the less massive objects form first, followed later by more massive ones. In the range 0.5

Lopes, Amanda R.; Iribarrem, Alvaro; Ribeiro, Marcelo B.; Stoeger, William R.

2014-12-01

428

Galaxy Cosmological Mass Function  

E-print Network

We study the galaxy cosmological mass function (GCMF) in a semi-empirical relativistic approach using observational data provided by galaxy redshift surveys. Starting from the theory of Ribeiro & Stoeger (2003, arXiv:astro-ph/0304094) between the mass-to-light ratio, the selection function obtained from the luminosity function (LF) data and the luminosity density, the average luminosity $L$ and the average galactic mass $\\mathcal{M}_g$ are computed in terms of the redshift. $\\mathcal{M}_g$ is also alternatively estimated by a method that uses the galaxy stellar mass function (GSMF). Comparison of these two forms of deriving the average galactic mass allows us to infer a possible bias introduced by the selection criteria of the survey. We used the FORS Deep Field galaxy survey sample of 5558 galaxies in the redshift range $0.5 < z < 5.0$ and its LF Schechter parameters in the B-band, as well as this sample's stellar mass-to-light ratio and its GSMF data. Assuming ${\\mathcal{M}_{g_0}} \\approx 10^{11} \\mathcal{M}_\\odot$ as the local value of the average galactic mass, the LF approach results in $L_{B} \\propto (1+z)^{(2.40 \\pm 0.03)}$ and $\\mathcal{M}_g \\propto (1+z)^{(1.1\\pm0.2)}$. However, using the GSMF results produces $\\mathcal{M}_g \\propto (1+z)^{(-0.58 \\pm 0.22)}$. We chose the latter result as it is less biased. We then obtained the theoretical quantities of interest, such as the differential number counts, to calculate the GCMF, which can be fitted by a Schechter function. The derived GCMF follows theoretical predictions in which the less massive objects form first, being followed later by more massive ones. In the range $0.5 < z < 2.0$ the GCMF has a strong variation that can be interpreted as a higher rate of galaxy mergers or as a strong evolution in the star formation history of these galaxies.

Amanda R. Lopes; Alvaro Iribarrem; Marcelo B. Ribeiro; William R. Stoeger

2014-12-03

429

NIST Handbook of Mathematical Functions  

Microsoft Academic Search

Modern developments in theoretical and applied science depend on knowledge of the properties of mathematical functions, from elementary trigonometric functions to the multitude of special functions. These functions appear whenever natural phenomena are studied, engineering problems are formulated, and numerical simulations are per- formed. They also crop up in statistics, financial models, and economic analysis. Using them effectively requires practitioners

Frank W. J. Olver; Daniel W. Lozier; Ronald F. Boisvert

2010-01-01

430

Functional Foods for Women's Health.  

ERIC Educational Resources Information Center

Describes functional foods for women's health (foods or food ingredients that provide health benefits beyond basic nutrition), explaining that both whole and modified foods can be included as functional foods. The paper discusses the history, regulation, and promotion of functional foods; consumer interest in functional foods; how to incorporate…

Lindeman, Alice K.

2002-01-01

431

Partial Functions . . . Definition of a . . .  

E-print Network

the bijection m 7! am 1 . Let us recall the definition of a partial function. #12;Partial Functions to an infinite computation. A partial function f: A ! B is a total function i dom(f) = A. It is customary to call

Gallier, Jean

432

Logical Definability of Counting Functions  

Microsoft Academic Search

The relationship between counting functions and logical expressibility is explored. The most well studied class of counting functions is P, which consists of the functions counting the accepting computation paths of a nondeterministic polynomial-time Turing machine. For a logic L, L is the class of functions on finite structures (of a fixed signature) counting the tuples (T¯, c¯) satisfying a

Kevin J. Compton; Erich Grädel

1994-01-01

433

Spline Functions in Data Analysis  

Microsoft Academic Search

The use of spline functions in the analysis of empirical two-dimensional data (yi, xi) is described. The definition of spline functions as piecewise polynomials with continuity conditions give them unique properties as empirical function. They can represent any variation of y with x arbitrarily well over wide intervals of x. Furthermore, due to the local properties of the spline functions,

Svante Wold

1974-01-01

434

[Functional pathophysiology of consciousness].  

PubMed

Consciousness (Latin conscientia "moral conscience"), according to the English philosopher John Locke (1632-1704) [103], is the awareness of all that occurs in the mind of a person, whereas the American philosopher John Searle (2000) defined it as "inner qualitative, subjective states and processes of awareness". In modern science it is defined as a continuous state of full awareness of the Self and one's relationship to the external and internal environment, describing the degree of wakefulness in which an organism recognizes stimuli. This widely discussed biological term for complex neuronal processes that allow an individuum to recognize itself and its environment and to act accordingly, has been and still is the subject of much research in philosophy and natural/neuroscience. Its definition is often used for awareness and recognition, too. While the Egyptians in the papyrus Edwin Smith already recognized the brain as the seat of consciousness, René Descartes (1644 [36]) believed its special structure should be "a small gland in the middle", but the anatomical structures and physiological processes involved in consciousness were elucidated only in the middle of the 20th century. Neuronal substrates include several functional networks that are hierarchically organized and cooperate functionally. The lowest level is the mesencephalic formatio reticularis and its projections to the thalamus that were identified als ascending reticular system (ARAS) by the classical experiments of Moruzzi and Magoun, whereas later analyses of patients with impaired consciousness provided further insights. The mesencephalic ARAS as motor of the function of higher structures projects 1. via the reticular thalamus diffusely to the cortex, 2. via hypothalamus to the basal forebrain and limbic system, and 3. to the medial raphe of the brainstem and locus coeruleus and their diffuse cortical projections. The reticular system is stimulated directly and indirectly via numerous collaterals from important somatic and sensory pathways and acts as a control system of neuronal activities of the cerebral cortex. The principal function of the ARAS is to focus our alertness on specific stimuli or internal processes, which run via complex neuronal cell groups and numerous neurotransmitters that influence various aspects of consciousness and wakefulness. Stimulation of the ARAS produces an arousal reaction as the electric correlate of consciousness; its destruction causes coma and related states. The highest level are cortical (prefrontal and association) networks for recognition, motor activity, longterm memory and attention, the left hemisphere being considered as the dominant one. Different levels of consciousness are distinguished: 1. hyperalertness, 2. alertness (normal state of wakefulness), 3. somnolence or lethargy, 4. obtundation with tendency to fall asleep, 5. stupor, 6. coma and its subtypes, like akinetic mutism, apallic syndrome or persistent vegative state, locked-in syndrome, delirium, and catatonia. They are caused by damages in various functional levels of the brain, by psychogenic factors or experimentally, and are accompanied by characteristic neurological and psychiatric disorders. The relevant morphological lesions can be detected by electrophysiological and imaging studies. The bases of functional anatomy and pathophysiology of consciousness, its cognitive aspects and its major disorders, their causes and functional substrates with reference to sleep and both spontaneous and iatrogenic disorders of consciousness are critically summarized. PMID:19573504

Jellinger, Kurt A

2009-01-01

435

Monocyte function in cirrhosis.  

PubMed Central

Monocyte function has been studied in a total of 51 patients with biopsy-proven cirrhosis and 35 controls. There was significantly reduced monocyte spreading (p less than 0.05), chemotaxis (p less than 0.02), bacterial phagocytosis (p less than 0.05) and bacterial killing (p less than 0.02) in the cirrhotics compared to the controls. Monocytes from patients with cirrhosis produced significantly less of the lysosomal enzymes N-acetyl beta-glucosaminidase and beta-glucuronidase than those obtained from the controls (p less than 0.02). There was no significant difference in the number of monocytes obtained, the number of macrophage precursors, and the nitro-blue tetrazoline (NBT) reduction between the cirrhotic and the controls. The reduced function appeared to be mainly due to a circulating inhibitory factor and could be corrected by incubation of the cirrhotic cells in serum from control subjects. The response of monocytes from patients with cirrhosis did not differ from the controls in their response to added endotoxin or latex particles suggesting that they are capable of a normal response in the absence of the inhibitory factor. Paired specimens of portal and systemic serum were collected from patients with no evidence of liver disease undergoing vascular surgery. When added to normal human monocytes the portal serum caused a significant reduction in bacterial killing (p less than 0.02) and chemotaxis (p less than 0.05) compared to results obtained in the paired systemic serum. Mixing experiments suggests the presence of an active inhibitor in the portal serum. The results suggest that monocyte function is reduced in cirrhosis apparently due to a serum inhibitor which may have originated from the portal vein. The abnormalities may account in part for the increased susceptibility of these patients to infection. PMID:7119129

Holdstock, G; Leslie, B; Hill, S; Tanner, A; Wright, R

1982-01-01

436

Defining functional dyspepsia.  

PubMed

Dyspepsia and functional dyspepsia represent a highly significant public health issue. A good definition of dyspepsia is key for helping us to better approach symptoms, decision making, and therapy indications.During the last few years many attempts were made at establishing a definition of dyspepsia. Results were little successful on most occasions, and clear discrepancies arose on whether symptoms should be associated with digestion, which types of symptoms were to be included, which anatomic location should symptoms have, etc.The Rome III Committee defined dyspepsia as "a symptom or set of symptoms that most physicians consider to originate from the gastroduodenal area", including the following: postprandial heaviness, early satiety, and epigastric pain or burning. Two new entities were defined: a) food-induced dyspeptic symptoms (postprandial distress syndrome); and b) epigastric pain (epigastric pain syndrome). These and other definitions have shown both strengths and weaknesses. At times they have been much too complex, at times much too simple; furthermore, they have commonly erred on the side of being inaccurate and impractical. On the other hand, some (the most recent ones) are difficult to translate into the Spanish language. In a meeting of gastroenterologists with a special interest in digestive functional disorders, the various aspects of dyspepsia definition were discussed and put to the vote, and the following conclusions were arrived at: dyspepsia is defined as a set of symptoms, either related or unrelated to food ingestion, localized on the upper half of the abdomen. They include: a) epigastric discomfort (as a category of severity) or pain; b) postprandial heaviness; and c) early satiety. Associated complaints include: nausea, belching, bloating, and epigastric burn (heartburn). All these must be scored according to severity and frequency. Furthermore, psychological factors may be involved in the origin of functional dyspepsia. On the other hand, it has proven very difficult to establish a clear correlation between symptoms and pathophysiological mechanisms. PMID:22217348

Mearin, Fermín; Calleja, José Luis

2011-12-01

437

Dual-functional semithiobambusurils.  

PubMed

Semithiobambusurils, which represent a new family of macrocyclic host molecules, have been prepared by a convenient, scalable synthesis. These new cavitands are double functional: they strongly bind a broad variety of anions in their interiors and metal ions at their sulfur-edged portals. The solid-state structure of semithiobambus[4]uril with HgCl2 demonstrates the ability of these compounds to form linear chains of coordination polymers with thiophillic metal ions. The crystal structure of semithiobambus[6]uril with tetraphenylphosphonium bromide exhibits the unique anion-binding properties of the host cavity and the characteristics of the binding site. PMID:25417852

Singh, Mandeep; Solel, Ephrath; Keinan, Ehud; Reany, Ofer

2015-01-01

438

The LISA Response Function  

E-print Network

The orbital motion of the Laser Interferometer Space Antenna (LISA) introduces modulations into the observed gravitational wave signal. These modulations can be used to determine the location and orientation of a gravitational wave source. The complete LISA response to an arbitary gravitational wave is derived using a coordinate free approach in the transverse-traceless gauge. The general response function reduces to that found by Cutler (PRD 57, 7089 1998) for low frequency, monochromatic plane waves. Estimates of the noise in the detector are found to be complicated by the time variation of the interferometer arm lengths.

Neil J. Cornish; Louis J. Rubbo

2003-01-13

439

Functional Mediastinal Pheochromocytoma  

PubMed Central

A 36-year-old man visited Yeungnam University Hospital with a sudden onset of palpitation, headache, and was found to be hypertensive. Chest radiography showed a 6 cm sized mass lesion on the posterior mediastinum. A biochemical study showed elevated levels of catecholamines. An I-123 metaiodobenzylguanidine scan revealed a hot uptake lesion on the posterior mediastinum. The patient was prepared for surgery with ? and ? blocking agents. Two months later, we removed the tumor successfully. A histological study proved that the resected tumor was mediastinal pheochromocytoma. Functional mediastinal pheochromocytomas are rare. Therefore, we reported the case with a literature review. PMID:23423879

Lee, Seok Soo; Lee, Jung Cheul; Kim, Myeong Su; Choi, Joon Hyuk

2013-01-01

440

Graphs and Functions  

NSDL National Science Digital Library

Students will learn about NASA's Radiation Belt Storm Probes (RBSP), Earth's van Allen Radiation Belts, and space weather through reading a NASA press release and viewing a NASA eClips video segment. Then students will use simple linear functions to examine the scale of the radiation belts and the strength of Earth's magnetic field. This activity is part of the Space Math multimedia modules that integrate NASA press releases, NASA archival video, and mathematics problems targeted at specific math standards commonly encountered in middle school textbooks. The modules cover specific math topics at multiple levels of difficulty with real-world data and use the 5E instructional sequence.

441

New Functions in GCN  

NASA Astrophysics Data System (ADS)

The Gamma-ray Coordinates Network (GCN) is continually being modified and enhanced to serve the world community for real-time transient astronomy. We will discuss the new features, functionality, and notice types that have been added to the system in the last two years. This includes a new filtering scheme which goes from 6 filtering parameters to 14 parameters. This will allow the follow-up user community more flexibility in selecting which notices they receive. This is important given the ever increasing array of notice types available. The VOEvent email format and socket format will also be described.

Barthelmy, Scott Douglas

2010-02-01

442

The Broadening Functions Technique  

NASA Astrophysics Data System (ADS)

Essential assumptions and features of the Broadening Function (BF) technique are presented. A distinction between BF determination and the BF concept and utilization is made. The BF's can be determined in various ways. The approach based on linear deconvolution involving stellar templates, as used during the DDO program (1999 - 2008) is described, but the LSD technique would also give excellent results. The BF concept to prove and/or verify photometric light-curve solutions has so far been very limited to only a few W UMa-type binaries, with AW UMa giving particularly unexpected results.

Rucinski, Slavek M.

2012-04-01

443

Implicit Density Functional Theory  

E-print Network

A fermion ground state energy functional is set up in terms of particle density, relative pair density, and kinetic energy tensor density. It satisfies a minimum principle if constrained by a complete set of compatibility conditions. A partial set, which thereby results in a lower bound energy under minimization, is obtained from the solution of model systems, as well as a small number of exact sum rules. Prototypical application is made to several one-dimensional spinless non-interacting models. The effectiveness of "atomic" constraints on model "molecules" is observed, as well as the structure of systems with only finitely many bound states.

Liu, B; Liu, Bin; Percus, Jerome K.

2006-01-01

444

Executive functions in dyslexia.  

PubMed

This study focused on executive functions in dyslexia. A group of 43 heavily-affected young dyslexics, divided into two groups based on the results of a receptive language test, and 20 non-dyslexic controls, were tested with a Dichotic Listening Test, the Stroop Color Word Test and the Wisconsin Card Sorting Test. The dyslexic subjects demonstrated significant impairment on all tasks, but with different patterns of impairment according to the subgrouping. The subgroups were equally impaired on the Dichotic Listening Test, but differed on the Stroop and the Wisconsin Tests. The data support a hypothesis suggesting executive problems in dyslexia, depending on receptive language skills. PMID:10980667

Helland, T; Asbjørnsen, A

2000-03-01

445

Bivariate lognormal density function  

E-print Network

. H. Matis and. Dr. C. K. Chui. TABLE OF CONTENTS CHAPTER Page I INTRODUCTION 1. 1 Current Status of' the Theory 1. 2 Aims of' the investigation 1. 3 Possible Applications 1 3 3 II THE PARA|%TER ESTIMATION 2. 1 Problem Description 2. 2... The Estimates RELATED PROBLHMS 3. 1 Missing Data Problem 5 1. 4 1. 6 16 3, 1. 1 Method. of Mm~ imum Likelihood 3. 1, 2 Smith-Hocking Procedure 17 19 IV 3. 2 The Hs. zard. Function MONTE CARLO STUDY 4. 1 The Simulation Problem 4. 2 The Simulation...

Schreyer, Glenn William

1972-01-01

446

Skulls : structure and function  

NSDL National Science Digital Library

Skulls have been designed for both form and function. Through the use of text and labeled photographs, this website explains how specific skull adaptations meet the needs of organisms. For instance, visitors will discover that some beaks of macaws are attached to their skull only through ligaments to limit the amount of force put on the skull when the birds crack open nuts. The site also presents a series of skull facts, questions, and answers provided by scientists. A unique feature allows visitors to rotate images of skulls 360 degrees, so they can view the different adaptations in form from all angles. Copyright 2005 Eisenhower National Clearinghouse

California Academy of Sciences

2005-01-01

447

Cholesterol oxidase: physiological functions  

PubMed Central

An important aspect of catalysis by cholesterol oxidase (3?-hydroxysteroid oxidase) is the nature of its association with the lipid bilayer that contains the sterol substrate. Efficient catalytic turnover is affected by the association of the protein with the membrane as well as the solubility of the substrate in the lipid bilayer. In this review, the binding of cholesterol oxidase to the lipid bilayer, its turnover of substrates presented in different physical environments, and how these conditions affect substrate specificity are discussed. The physiological functions of the enzyme in bacterial metabolism, pathogenesis, and macrolide biosynthesis are reviewed in this context. PMID:19843168

Kreit, Joseph; Sampson, Nicole S.

2009-01-01

448

Functional Burden of Strabismus  

PubMed Central

IMPORTANCE Binocular summation (BiS) is defined as the superiority of visual function for binocular over monocular viewing. Binocular summation decreases with age and large interocular differences in visual acuity. To our knowledge, BiS has not heretofore been well studied as a functional measure of binocularity in strabismus. OBJECTIVE To evaluate the effect of strabismus on BiS using a battery of psychophysical tasks that are clinically relevant and easy to use and to determine whether strabismus is associated with binocular inhibition in extreme cases. DESIGN Case-control study. SETTING University-based eye institute. PARTICIPANTS Strabismic patients recruited during 2010 to 2012 from a preoperative clinic and control participants with no history of eye disease other than refractive error. INTERVENTION A battery of psychophysical and electrophysiological tests including Early Treatment Diabetic Retinopathy Study visual acuity, Sloan low-contrast acuity (LCA) (2.5% and 1.25%), Pelli-Robson contrast sensitivity, and sweep visual evoked potential contrast sensitivity. MAIN OUTCOME AND MEASURE Binocular summation was calculated as the ratio between binocular and better-eye individual scores. RESULTS Sixty strabismic and 80 control participants were prospectively examined (age range, 8–60 years). Mean BiS was significantly lower in the strabismic patients than controls for LCA (2.5% and 1.25%, P = .005 and <.001, respectively). For 1.25% LCA, strabismic patients had a mean BiS score less than 1, indicating binocular inhibition (ie, the binocular score was less than that of the better eye’s monocular score). There was no significant difference in BiS for contrast thresholds on Early Treatment Diabetic Retinopathy Study visual acuity, Pelli-Robson contrast sensitivity, or sweep visual evoked potential contrast sensitivity. Regression analysis revealed a significant worsening of BiS with strabismus for 2.5% (P = .009) and 1.25% (P = .002) LCA, after accounting for age. CONCLUSIONS AND RELEVANCE Strabismic patients demonstrate subnormal BiS and even binocular inhibition for LCA, suggesting that strabismus impairs visual function more than previously appreciated. This may explain why strabismic patients who are not diplopic close 1 eye in visually demanding situations. This finding clarifies the visual deficits impacting quality of life in strabismic patients and may represent a novel measure by which to evaluate and monitor function in strabismus. PMID:24052160

Pineles, Stacy L.; Velez, Federico G.; Isenberg, Sherwin J.; Fenoglio, Zachary; Birch, Eileen; Nusinowitz, Steven; Demer, Joseph L.

2014-01-01

449

Functional Dyspepsia Today  

PubMed Central

ABSTRACT Functional dyspepsia (FD) is a disorder presenting with symptoms such as postprandial fullness, early satiety or epigastric pain. Although there is a 10 to 30% reported prevalence worldwide, there is currently no clear explanation of the pathophysiology behind this condition. Motility disorders, visceral hypersensitivity, acid disorders, Helicobacter pylori infection or psychosocial factors have all been reported to play a part in the pathophysiology of FD. The diagnosis of FD is one of exclusion, based on the Rome III criteria. The main therapeutic modalities include lifestyle changes, eradicating Helicobacter pylori infection and treatment with either proton pump inhibitors, prokinetics or antidepressants. PMID:24023602

VOIOSU, Theodor Alexandru; GIURCAN, Roxana; VOIOSU, Andrei Mihai; VOIOSU, Mihail Radu

2013-01-01

450

Polyoxomolybdates functionalized with phosphonocarboxylates.  

PubMed

The novel, functionalized heteropolymolybdate [(O(2)CCH(2)PO(3))(2)Mo(5)O(15)](6-) (1) has been synthesized and characterized by IR and (31)P NMR spectroscopy and elemental analysis. Single-crystal X-ray analysis was carried out on Rb(4)KNa[(O(2)CCH(2)PO(3))(2)Mo(5)O(15)].H(2)O, which crystallizes in the monoclinic system, space group P2(1)/n, with a = 10.146(2) A, b = 13.704(3) A, c = 20.577(4) A, beta = 94.88(3) degrees, and Z = 4. The title polyanion consists of a ring of five MoO(6) octahedra with four edge junctions and one corner junction. This nonplanar arrangement is stabilized by two phosphonocarboxylate groups that are bound via their phosphonate functionalities on opposite sides of the ring. As a result the two dangling arms with their terminal carboxylate groups protrude away from the molybdenum-oxo framework in diametrically opposed directions. The solid-state structure of 1 is preserved in solution on the basis of NMR. We also report on the synthesis and characterization of the isostructural derivative [(O(2)CC(2)H(4)PO(3))(2)Mo(5)O(15)](6-) (2). PMID:12588152

Kortz, Ulrich; Marquer, Catherine; Thouvenot, René; Nierlich, Martine

2003-02-24

451

The function of spermine.  

PubMed

Polyamines play important roles in cell physiology including effects on the structure of cellular macromolecules, gene expression, protein function, nucleic acid and protein synthesis, regulation of ion channels, and providing protection from oxidative damage. Vertebrates contain two polyamines, spermidine and spermine, as well as their precursor, the diamine putrescine. Although spermidine has an essential and unique role as the precursor of hypusine a post-translational modification of the elongation factor eIF5A, which is necessary for this protein to function in protein synthesis, no unique role for spermine has been identified unequivocally. The existence of a discrete spermine synthase enzyme that converts spermidine to spermine suggest that spermine must be needed and this is confirmed by studies with Gy mice and human patients with Snyder-Robinson syndrome in which spermine synthase is absent or greatly reduced. In both cases, this leads to a severe phenotype with multiple effects among which are intellectual disability, other neurological changes, hypotonia, and reduced growth of muscle and bone. This review describes these alterations and focuses on the roles of spermine which may contribute to these phenotypes including reducing damage due to reactive oxygen species, protection from stress, permitting correct current flow through inwardly rectifying K(+) channels, controlling activity of brain glutamate receptors involved in learning and memory, and affecting growth responses. Additional possibilities include acting as storage reservoir for maintaining appropriate levels of free spermidine and a possible non-catalytic role for spermine synthase protein. PMID:24395705

Pegg, Anthony E

2014-01-01

452

Process for functionalizing alkanes  

DOEpatents

Process for functionalizing saturated hydrocarbons comprising: (a) reacting said saturated hydrocarbons of the formula: R.sub.1 H wherein H represents a hydrogen atom; and R.sub.1 represents a saturated hydrocarbon radical, with a metal complex of the formula: CpRh[P(R.sub.2).sub.3 ]H.sub.2 wherein Cp represents a cyclopentadienyl or alkylcyclopentadienyl radical; Rh represents a rhodium atom; P represents a phosphorus atom; R.sub.2 represents a hydrocarbon radical; H represents a hydrogen atom, in the presence of ultraviolet radiation to form a hydridoalkyl complex of the formula: CpRh[P(R.sub.2).sub.3 ](R.sub.1)H (b) reacting said hydridoalkyl complex with an organic halogenating agent such as a tetrahalomethane or a haloform of the formulas: CX'X''X'''X'''' or CHX'X''X''' wherein X', X'', X'", X"" represent halogens selected from bromine, iodine or chlorine atom, at a temperature in the range of about -60.degree. to -17.degree. C. to form the corresponding haloalkyl complex of step (a) having the formula: CpRhPMe.sub.3 RX; and, (c) reacting said haloalkyl complex formed in (b) with halogen (X.sub.2) at a temperature in the range of about -60.degree. to 25.degree. C. (i.e., ambient) to form a functional haloalkyl compound.

Bergman, Robert G. (Kensington, CA); Janowicz, Andrew H. (Wilmington, DE); Periana, Roy A. (Berkeley, CA)

1988-01-01

453

Process for functionalizing alkanes  

DOEpatents

Process for functionalizing saturated hydrocarbons selectively in the terminal position comprising: (a) reacting said saturated hydrocarbons of the formula: RH where: H represents a hydrogen atom, and R represents a saturated hydrocarbon radical, with a metal complex of the formula: CpRhPMe.sub.3 H.sub.2 where: Cp represents a pentamethylated cyclopentadienyl radical, Rh represents a rhodium atom, P represents a phosphorous atom, Me represents a methyl group, H represents a hydrogen atom, in the presence of ultraviolet radiation at a temperature maintained at about -60.degree. to -17.degree. C. to form a hydridoalkyl complex of the formula: CpRhPMe.sub.3 RH (b) reacting said hydridoalkyl complex with a haloform of the formula: CHX.sub.3 where: X represents a bromine, iodine or chlorine atom, at a temperature in the range of about -60.degree. to -17.degree. C. to form the corresponding haloalkyl complex of step (a) having the formula: CpRhPMe.sub.3 RX; and, (c) reacting said haloalkyl complex formed in (b) with halogen (X.sub.2) at a temperature in the range of about -60.degree. to 25.degree. C. (i.e. ambient) to form a functional haloalkyl compound.

Bergman, Robert G. (Kensington, CA); Janowicz, Andrew H. (Wilmington, DE); Periana-Pillai, Roy A. (Berkeley, CA)

1985-01-01

454

Mast Cell Function  

PubMed Central

Since first described by Paul Ehrlich in 1878, mast cells have been mostly viewed as effectors of allergy. It has been only in the past two decades that mast cells have gained recognition for their involvement in other physiological and pathological processes. Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment. Mast cell maturation, phenotype and function are a direct consequence of the local microenvironment and have a marked influence on their ability to specifically recognize and respond to various stimuli through the release of an array of biologically active mediators. These features enable mast cells to act as both first responders in harmful situations as well as to respond to changes in their environment by communicating with a variety of other cells implicated in physiological and immunological responses. Therefore, the critical role of mast cells in both innate and adaptive immunity, including immune tolerance, has gained increased prominence. Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases. This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role. PMID:25062998

da Silva, Elaine Zayas Marcelino; Jamur, Maria Célia

2014-01-01

455

Pleural function and lymphatics.  

PubMed

The pleural space plays an important role in respiratory function as the negative intrapleural pressure regimen ensures lung expansion and in the mean time maintains the tight mechanical coupling between the lung and the chest wall. The efficiency of the lung-chest wall coupling depends upon pleural liquid volume, which in turn reflects the balance between the filtration of fluid into and its egress out of the cavity. While filtration occurs through a single mechanism passively driving fluid from the interstitium of the parietal pleura into the cavity, several mechanisms may co-operate to remove pleural fluid. Among these, the pleural lymphatic system emerges as the most important one in quantitative terms and the only one able to cope with variable pleural fluid volume and drainage requirements. In this review, we present a detailed account of the actual knowledge on: (a) the complex morphology of the pleural lymphatic system, (b) the mechanism supporting pleural lymph formation and propulsion, (c) the dependence of pleural lymphatic function upon local tissue mechanics and (d) the effect of lymphatic inefficiency in the development of clinically severe pleural and, more in general, respiratory pathologies. PMID:23009260

Negrini, D; Moriondo, A

2013-02-01

456

Indirect photobiomodulation in functional networks  

NASA Astrophysics Data System (ADS)

Photobiomodulation (PBM) is a non-damaged modulation of laser irradiation or monochromatic light (LI) on a biosystem function. It depends on whether the function is in its function-specific homeostasis (FSH), a negative feedback response for the function to be performed perfectly. Many redundant pathways (RPs) maintain the same cellular function. The full activation of any of RPs can maintain a normal function in its FSH, but partial activation of all the RPs can only maintain a dysfunctional function far from its FSH. A PBM may self-adaptively modulate the activation of a partially activated RP of a normal function until it is fully activated and the normal function is then upgraded. This PBM is called indirect PBM (iPBM). The iPBM on cells such as tumor cells, myoblast cells and fibroblasts and other biosystems and their applications would be reviewed in this paper.

Liu, Timon Cheng-Yi; Zhu, Wei-Wei; Yang, Xiang-Bo

2012-12-01

457

Structural & FunctionalStructural & Functional GenomicsGenomics  

E-print Network

NCBINCBI Structural & FunctionalStructural & Functional GenomicsGenomics:: The Information Information National Library of Medicine National Institutes of Health Bethesda, Maryland Current Topics in Genome Analysis, 4 November 1997 #12;NCBINCBI Growth of Biomedical Information (1)Growth of Biomedical

Boguski, Mark S.

458

Functional Integration on Constrained Function Spaces I: Foundations  

E-print Network

Analogy with Bayesian inference is used to formulate constraints within a scheme for functional integration proposed by Cartier and DeWitt-Morette. According to the analogy, functional counterparts of conditional and conjugate probability distributions are introduced for integrators. The analysis leads to some new functional integration tools and methods that can be applied to the study of constrained dynamical systems.

J. LaChapelle

2014-11-18

459

Computer Experiments for Function Approximations  

SciTech Connect

This research project falls in the domain of response surface methodology, which seeks cost-effective ways to accurately fit an approximate function to experimental data. Modeling and computer simulation are essential tools in modern science and engineering. A computer simulation can be viewed as a function that receives input from a given parameter space and produces an output. Running the simulation repeatedly amounts to an equivalent number of function evaluations, and for complex models, such function evaluations can be very time-consuming. It is then of paramount importance to intelligently choose a relatively small set of sample points in the parameter space at which to evaluate the given function, and then use this information to construct a surrogate function that is close to the original function and takes little time to evaluate. This study was divided into two parts. The first part consisted of comparing four sampling methods and two function approximation methods in terms of efficiency and accuracy for simple test functions. The sampling methods used were Monte Carlo, Quasi-Random LP{sub {tau}}, Maximin Latin Hypercubes, and Orthogonal-Array-Based Latin Hypercubes. The function approximation methods utilized were Multivariate Adaptive Regression Splines (MARS) and Support Vector Machines (SVM). The second part of the study concerned adaptive sampling methods with a focus on creating useful sets of sample points specifically for monotonic functions, functions with a single minimum and functions with a bounded first derivative.

Chang, A; Izmailov, I; Rizzo, S; Wynter, S; Alexandrov, O; Tong, C

2007-10-15

460

Functionalization of ?-synuclein fibrils.  

PubMed

The propensity of peptides and proteins to form self-assembled structures has very promising applications in the development of novel nanomaterials. Under certain conditions, amyloid protein ?-synuclein forms well-ordered structures - fibrils, which have proven to be valuable building blocks for bionanotechnological approaches. Herein we demonstrate the functionalization of fibrils formed by a mutant ?-synuclein that contains an additional cysteine residue. The fibrils have been biotinylated via thiol groups and subsequently joined with neutravidin-conjugated gold nanoparticles. Atomic force microscopy and transmission electron microscopy confirmed the expected structure - nanoladders. The ability of fibrils (and of the additional components) to assemble into such complex structures offers new opportunities for fabricating novel hybrid materials or devices. PMID:25671157

Povilonien?, Simona; ?asait?, Vida; Bukauskas, Virginijus; Šetkus, Ar?nas; Staniulis, Juozas; Meškys, Rolandas

2015-01-01