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Sample records for mediolateral functional dichotomy

  1. Electrophysiological evidence of mediolateral functional dichotomy in the rat nucleus accumbens during cocaine self-administration II: phasic firing patterns.

    PubMed

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

    2010-05-01

    In the cocaine self-administering rat, individual nucleus accumbens (NAcc) neurons exhibit phasic changes in firing rate within minutes and/or seconds of lever presses (i.e. slow phasic and rapid phasic changes, respectively). To determine whether neurons that demonstrate these changes during self-administration sessions are differentially distributed in the NAcc, rats were implanted with jugular catheters and microwire arrays in different NAcc subregions (core, dorsal shell, ventromedial shell, ventrolateral shell, or rostral pole). Neural recording sessions were typically conducted on days 13-17 of cocaine self-administration (0.77 mg/kg per 0.2-mL infusion; fixed-ratio 1 schedule of reinforcement; 6-h daily sessions). Pre-press rapid phasic firing rate changes were greater in lateral accumbal (core and ventrolateral shell) than in medial accumbal (dorsal shell and rostral pole shell) subregions. Slow phasic pattern analysis revealed that reversal latencies of neurons that exhibited change + reversal patterns differed mediolaterally: medial NAcc neurons exhibited more early reversals and fewer progressive/late reversals than lateral NAcc neurons. Comparisons of firing patterns within individual neurons across time bases indicated that lateral NAcc pre-press rapid phasic increases were correlated with tonic increases. Tonic decreases were correlated with slow phasic patterns in individual medial NAcc neurons, indicative of greater pharmacological sensitivity of neurons in this region. On the other hand, the bias of the lateral NAcc towards increased pre-press rapid phasic activity, coupled with a greater prevalence of tonic increase firing, may reflect particular sensitivity of these neurons to excitatory afferent signaling and perhaps differential pharmacological influences on firing rates between regions. PMID:20525080

  2. Structural and functional dichotomy of human midcingulate cortex.

    PubMed

    Vogt, Brent A; Berger, Gail R; Derbyshire, Stuart W G

    2003-12-01

    Anterior cingulate cortex is comprised of perigenual and midcingulate regions based on cytology, imaging and connections. Its anterior (aMCC) and posterior (pMCC) parts and transition to posterior area 23 were evaluated in six human cingulate gyri with Nissl staining and immunoreactions for neuron-specific nuclear binding protein and intermediate neurofilament proteins (NFP), and their pain and emotion functions evaluated in standard coordinates. Morphological differences included a poorly differentiated layer III with few NFP-expressing neurons in aMCC and a very dense layer Va with small and large pyramids intermingled in pMCC. The density of NFP-positive, layer Vb neurons was higher in pMCC than in aMCC. The junction of pMCC with area 23 had a dysgranular area 23d with clumps of layer IV neurons and a very dense layer Va. Each case was co-registered to standard coordinates and the regional borders identified and measured. Although both regions had overall equivalent activations during noxious cutaneous thermal stimulation, the posterior two-thirds of pMCC was relatively inactive. About 60% of fear-induced activity was in aMCC, sadness and happiness activated perigenual cortex, and neither were activated with non-emotion tasks. Thus, pain activity is coupled to fear in aMCC, while other MCC processing is not related to affect. Beyond midcingulate duality, this is the first report of a very dense layer Va for areas p24' and 23 and the features of transitional area 23d. The MCC dichotomy suggests that two circuits differentially regulate the two cingulate motor areas, and involvement of aMCC in pain and fear make it selectively vulnerable to chronic pain and stress syndromes. PMID:14656310

  3. Neurocognitive Functioning in Schizophrenia and Bipolar Disorder: Clarifying Concepts of Diagnostic Dichotomy vs. Continuum

    PubMed Central

    Kuswanto, Carissa N.; Sum, Min Y.; Sim, Kang

    2013-01-01

    The Kraepelinian dichotomy posits that patients with schizophrenia (SCZ) and bipolar disorder (BD) present as two separate psychotic entities such that they differ in terms of clinical severity including neurocognitive functioning. Our study aimed to specifically compare and contrast the level of neurocognitive functioning between SCZ and BD patients and identify predictors of their poor neurocognitive functioning. We hypothesized that patients with SCZ had a similar level of neurocognitive impairment compared with BD. About 49 healthy controls (HC), 72 SCZ, and 42 BD patients who were matched for age, gender, and premorbid IQ were administered the Brief Assessment of Cognition battery (BAC). Severity of psychopathology and socio-occupational functioning were assessed for both patients groups. Both BD and SCZ groups demonstrated similar patterns of neurocognitive deficits across several domains (verbal memory, working memory, semantic fluency, processing speed) compared with HC subjects. However, no significant difference was found in neurocognitive functioning between BD and SCZ patients, suggesting that both patient groups suffer the same degree of neurocognitive impairment. Patients with lower level of psychosocial functioning [F(1,112) = 2.661, p = 0.009] and older age [F(1,112) = −2.625, p = 0.010], not diagnosis or doses of psychotropic medications, predicted poorer overall neurocognitive functioning as measured by the lower BAC composite score. Our findings of comparable neurocognitive impairments between SCZ and BD affirm our hypothesis and support less the Kraepelinian concept of dichotomy but more of a continuum of psychotic spectrum conditions. This should urge clinicians to investigate further the underlying neural basis of these neurocognitive deficits, and be attentive to the associated socio-demographic and clinical profile in order to recognize and optimize early the management of the widespread neurocognitive deficits in patients with SCZ and BD. PMID:24367337

  4. Estimates for the Green's function and parameters of exponential dichotomy of a hyperbolic operator semigroup and linear relations

    NASA Astrophysics Data System (ADS)

    Baskakov, A. G.

    2015-08-01

    By applying Lyapunov's equation, the method of similar operators, and the methods of harmonic analysis, we obtain estimates for the parameters of exponential dichotomy and for the Green's function constructed for a hyperbolic operator semigroup and a hyperbolic linear relation. Estimates are obtained using quantities which are determined by the resolvent of the infinitesimal operator of the operator semigroup and of the linear relation. Bibliography: 51 titles.

  5. Dichotomy of AML1-ETO Functions: Growth Arrest versus Block of Differentiation†

    PubMed Central

    Burel, Sebastien A.; Harakawa, Nari; Zhou, Liming; Pabst, Thomas; Tenen, Daniel G.; Zhang, Dong-Er

    2001-01-01

    The fusion gene AML1-ETO is the product of t(8;21)(q22;q22), one of the most common chromosomal translocations associated with acute myeloid leukemia. To investigate the impact of AML1-ETO on hematopoiesis, tetracycline-inducible AML1-ETO-expressing cell lines were generated using myeloid cells. AML1-ETO is tightly and strongly induced upon tetracycline withdrawal. The proliferation of AML1-ETO+ cells was markedly reduced, and most of the cells eventually underwent apoptosis. RNase protection assays revealed that the amount of Bcl-2 mRNA was decreased after AML1-ETO induction. Enforced expression of Bcl-2 was able to significantly delay, but not completely overcome, AML1-ETO-induced apoptosis. Prior to the onset of apoptosis, we also studied the ability of AML1-ETO to modulate differentiation. AML1-ETO expression altered granulocytic differentiation of U937T-A/E cells. More significantly, this change of differentiation was associated with the down-regulation of CCAAT/enhancer binding protein α (C/EBPα), a key regulator of granulocytic differentiation. These observations suggest a dichotomy in the functions of AML1-ETO: (i) reduction of granulocytic differentiation correlated with decreased expression of C/EBPα and (ii) growth arrest leading to apoptosis with decreased expression of CDK4, c-myc, and Bcl-2. We predict that the preleukemic AML1-ETO+ cells must overcome AML1-ETO-induced growth arrest and apoptosis prior to fulfilling their leukemogenic potential. PMID:11463839

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

    PubMed Central

    Kendler, KS

    2012-01-01

    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

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

    PubMed Central

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

    2013-01-01

    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

  8. The functional role of the inferior parietal lobe in the dorsal and ventral stream dichotomy.

    PubMed

    Singh-Curry, Victoria; Husain, Masud

    2009-05-01

    Current models of the visual pathways have difficulty incorporating the human inferior parietal lobe (IPL) into dorsal or ventral streams. Some recent proposals have attempted to integrate aspects of IPL function that were not hitherto dealt with well, such as differences between the left and right hemisphere and the role of the right IPL in responding to salient environmental events. However, we argue that these models also fail to capture adequately some important findings regarding the functions of the IPL. Here we critically appraise existing proposals regarding the functional architecture of the visual system, with special emphasis on the role of this region, particularly in the right hemisphere. We review evidence that shows the right IPL plays an important role in two different, but broadly complementary, aspects of attention: maintaining attentive control on current task goals as well as responding to salient new information or alerting stimuli in the environment. In our view, findings from functional imaging, electrophysiological and lesion studies are all consistent with the view that this region is part of a system that allows flexible reconfiguration of behaviour between these two alternative modes of operation. Damage to the right IPL leads to deficits in both maintaining attention and also responding to salient events, impairments that contribute to hemineglect, the classical syndrome that follows lesions of this region. PMID:19138694

  9. Evidence for two distinct stellar initial mass functions: probing for clues to the dichotomy

    SciTech Connect

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

    2014-12-01

    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, Y{sub *}, of the high and low Y{sub *} cluster populations are well-matched to those found in recent studies of early and late type galaxies, respectively.

  10. Thalamic Responses to Nociceptive-Specific Input in Humans: Functional Dichotomies and Thalamo-Cortical Connectivity.

    PubMed

    Bastuji, Hélène; Frot, Maud; Mazza, Stéphanie; Perchet, Caroline; Magnin, Michel; Garcia-Larrea, Luis

    2016-06-01

    While nociceptive cortical activation is now well characterized in humans, understanding of the nociceptive thalamus remains largely fragmentary. We used laser stimuli and intracerebral electrodes in 17 human subjects to record nociceptive-specific field responses in 4 human thalamic nuclei and a number of cortical areas. Three nuclei known to receive spinothalamic (STT) projections in primates (ventro-postero-lateral [VPL], anterior pulvinar [PuA], and central lateral [CL]) exhibited responses with similar latency, indicating their parallel activation by nociceptive afferents. Phase coherence analysis, however, revealed major differences in their functional connectivity: while VPL and PuA drove a limited set of cortical targets, CL activities were synchronized with a large network including temporal, parietal, and frontal areas. Our data suggest that STT afferents reach simultaneously a set of lateral and medial thalamic regions unconstrained by traditional nuclear borders. The broad pattern of associated cortical networks suggests that a single nociceptive volley is able to trigger the sensory, cognitive, and emotional activities that underlie the complex pain experience. The medial pulvinar, an associative nucleus devoid of STT input, exhibited delayed responses suggesting its dependence on descending cortico-thalamic projections. Its widespread cortical connectivity suggests a role in synchronizing parietal, temporal, and frontal activities, hence contributing to the access of noxious input to conscious awareness. PMID:25994963

  11. Mechanistic and structural insight into the functional dichotomy between interleukin-2 and interleukin-15

    PubMed Central

    Ring, Aaron M.; Lin, Jian-Xin; Feng, Dan; Mitra, Suman; Rickert, Mathias; Bowman, Gregory R.; Pande, Vijay S.; Li, Peng; Moraga, Ignacio; Spolski, Rosanne; Özkan, Engin; Leonard, Warren J.; Garcia, K. Christopher

    2012-01-01

    Interleukin-15 (IL-15) and IL-2 possess distinct immunological functions despite both signaling through IL-2Rβ and the common cytokine receptor γ-chain, γc, We find that in the IL-15—IL-15Rα—IL-2Rβ—γc quaternary complex structure, IL-15 heterodimerizes IL-2Rβ and γc identically to the IL-2—IL-2Rα—IL-2Rβ—γc complex, despite differing receptor-binding chemistries. IL-15Rα dramatically increases the affinity of IL-15 for IL-2Rβ, and this allostery is required for IL-15 trans-signaling versus IL-2 cis-signaling. Consistent with the identical IL-2Rβ—γc dimer geometry, IL-2 and IL-15 exhibited similar signaling properties in lymphocytes, with any differences resulting from disparate receptor affinities. Thus, IL-15 and IL-2 induce similar signals, and the cytokine-specificity of IL-2Rα versus IL-15Rα determines cellular responsiveness. These results provide important new insights for specific development of IL-15-versus IL-2-based immunotherapeutics. PMID:23104097

  12. Age Effects on Mediolateral Balance Control

    PubMed Central

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

    2014-01-01

    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

  13. A neuromechanical strategy for mediolateral foot placement in walking humans

    PubMed Central

    Rankin, Bradford L.; Buffo, Stephanie K.

    2014-01-01

    Stability is an important concern during human walking and can limit mobility in clinical populations. Mediolateral stability can be efficiently controlled through appropriate foot placement, although the underlying neuromechanical strategy is unclear. We hypothesized that humans control mediolateral foot placement through swing leg muscle activity, basing this control on the mechanical state of the contralateral stance leg. Participants walked under Unperturbed and Perturbed conditions, in which foot placement was intermittently perturbed by moving the right leg medially or laterally during the swing phase (by ∼50–100 mm). We quantified mediolateral foot placement, electromyographic activity of frontal-plane hip muscles, and stance leg mechanical state. During Unperturbed walking, greater swing-phase gluteus medius (GM) activity was associated with more lateral foot placement. Increases in GM activity were most strongly predicted by increased mediolateral displacement between the center of mass (CoM) and the contralateral stance foot. The Perturbed walking results indicated a causal relationship between stance leg mechanics and swing-phase GM activity. Perturbations that reduced the mediolateral CoM displacement from the stance foot caused reductions in swing-phase GM activity and more medial foot placement. Conversely, increases in mediolateral CoM displacement caused increased swing-phase GM activity and more lateral foot placement. Under both Unperturbed and Perturbed conditions, humans controlled their mediolateral foot placement by modulating swing-phase muscle activity in response to the mechanical state of the contralateral leg. This strategy may be disrupted in clinical populations with a reduced ability to modulate muscle activity or sense their body's mechanical state. PMID:24790168

  14. A neuromechanical strategy for mediolateral foot placement in walking humans.

    PubMed

    Rankin, Bradford L; Buffo, Stephanie K; Dean, Jesse C

    2014-07-15

    Stability is an important concern during human walking and can limit mobility in clinical populations. Mediolateral stability can be efficiently controlled through appropriate foot placement, although the underlying neuromechanical strategy is unclear. We hypothesized that humans control mediolateral foot placement through swing leg muscle activity, basing this control on the mechanical state of the contralateral stance leg. Participants walked under Unperturbed and Perturbed conditions, in which foot placement was intermittently perturbed by moving the right leg medially or laterally during the swing phase (by ∼50-100 mm). We quantified mediolateral foot placement, electromyographic activity of frontal-plane hip muscles, and stance leg mechanical state. During Unperturbed walking, greater swing-phase gluteus medius (GM) activity was associated with more lateral foot placement. Increases in GM activity were most strongly predicted by increased mediolateral displacement between the center of mass (CoM) and the contralateral stance foot. The Perturbed walking results indicated a causal relationship between stance leg mechanics and swing-phase GM activity. Perturbations that reduced the mediolateral CoM displacement from the stance foot caused reductions in swing-phase GM activity and more medial foot placement. Conversely, increases in mediolateral CoM displacement caused increased swing-phase GM activity and more lateral foot placement. Under both Unperturbed and Perturbed conditions, humans controlled their mediolateral foot placement by modulating swing-phase muscle activity in response to the mechanical state of the contralateral leg. This strategy may be disrupted in clinical populations with a reduced ability to modulate muscle activity or sense their body's mechanical state. PMID:24790168

  15. Functional dichotomy in the 16S rRNA (m1A1408) methyltransferase family and control of catalytic activity via a novel tryptophan mediated loop reorganization

    PubMed Central

    Witek, Marta A.; Conn, Graeme L.

    2016-01-01

    Methylation of the bacterial small ribosomal subunit (16S) rRNA on the N1 position of A1408 confers exceptionally high-level resistance to a broad spectrum of aminoglycoside antibiotics. Here, we present a detailed structural and functional analysis of the Catenulisporales acidiphilia 16S rRNA (m1A1408) methyltransferase (‘CacKam’). The apo CacKam structure closely resembles other m1A1408 methyltransferases within its conserved SAM-binding fold but the region linking core β strands 6 and 7 (the ‘β6/7 linker’) has a unique, extended structure that partially occludes the putative 16S rRNA binding surface, and sequesters the conserved and functionally critical W203 outside of the CacKam active site. Substitution of conserved residues in the SAM binding pocket reveals a functional dichotomy in the 16S rRNA (m1A1408) methyltransferase family, with two apparently distinct molecular mechanisms coupling cosubstrate/ substrate binding to catalytic activity. Our results additionally suggest that CacKam exploits the W203-mediated remodeling of the β6/7 linker as a novel mechanism to control 30S substrate recognition and enzymatic turnover. PMID:26609134

  16. Medio-Lateral Postural Instability in Subjects with Tinnitus

    PubMed Central

    Kapoula, Zoi; Yang, Qing; Lê, Thanh-Thuan; Vernet, Marine; Berbey, Nolwenn; Orssaud, Christophe; Londero, Alain; Bonfils, Pierre

    2011-01-01

    Background: Many patients show modulation of tinnitus by gaze, jaw or neck movements, reflecting abnormal sensorimotor integration, and interaction between various inputs. Postural control is based on multi-sensory integration (visual, vestibular, somatosensory, and oculomotor) and indeed there is now evidence that posture can also be influenced by sound. Perhaps tinnitus influences posture similarly to external sound. This study examines the quality of postural performance in quiet stance in patients with modulated tinnitus. Methods: Twenty-three patients with highly modulated tinnitus were selected in the ENT service. Twelve reported exclusively or predominately left tinnitus, eight right, and three bilateral. Eighteen control subjects were also tested. Subjects were asked to fixate a target at 40 cm for 51 s; posturography was performed with the platform (Technoconcept, 40 Hz) for both the eyes open and eyes closed conditions. Results: For both conditions, tinnitus subjects showed abnormally high lateral body sway (SDx). This was corroborated by fast Fourrier Transformation (FFTx) and wavelet analysis. For patients with left tinnitus only, medio-lateral sway increased significantly when looking away from the center. Conclusion: Similarly to external sound stimulation, tinnitus could influence lateral sway by activating attention shift, and perhaps vestibular responses. Poor integration of sensorimotor signals is another possibility. Such abnormalities would be accentuated in left tinnitus because of the importance of the right cerebral cortex in processing both auditory–tinnitus eye position and attention. PMID:21647364

  17. The End of a Chemical Dichotomy.

    ERIC Educational Resources Information Center

    MOSAIC, 1980

    1980-01-01

    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)

  18. Reconceptualizing the Native/Nonnative Speaker Dichotomy

    ERIC Educational Resources Information Center

    Faez, Farahnaz

    2011-01-01

    This study reconceptualizes the native/nonnative dichotomy and provides a powerful lens to examine linguistic identities. In a study of 25 linguistically diverse teacher candidates in Canada, the respondents' native and nonnative self-ascription and self-assessed level of proficiency was juxtaposed with the judgment of their instructors. This…

  19. Algebraic dichotomies with an application to the stability of Riemann solutions of conservation laws

    NASA Astrophysics Data System (ADS)

    Lin, Xiao-Biao

    Recently, there has been some interest on the stability of waves where the functions involved grow or decay at an algebraic rate |. In this paper we define the so-called algebraic dichotomy that may aid in treating such problems. We discuss the basic properties of the algebraic dichotomy, methods of detecting it, and calculating the power of the weight function. We present several examples: (1) The Bessel equation. (2) The n-degree Fisher type equation. (3) Hyperbolic conservation laws in similarity coordinates. (4) A system of conservation laws with a Dafermos type viscous regularization. We show that the linearized system generates an analytic semigroup in the space of algebraic decay functions. This example motivates our work on algebraic dichotomies.

  20. Mediolateral angular momentum changes in persons with amputation during perturbed walking.

    PubMed

    Sheehan, Riley C; Beltran, Eduardo J; Dingwell, Jonathan B; Wilken, Jason M

    2015-03-01

    Over 50% of individuals with lower limb amputation fall at least once each year. These individuals also exhibit reduced ability to effectively respond to challenges to frontal plane stability. The range of whole body angular momentum has been correlated with stability and fall risk. This study determined how lateral walking surface perturbations affected the regulation of whole body and individual leg angular momentum in able-bodied controls and individuals with unilateral transtibial amputation. Participants walked at fixed speed in a Computer Assisted Rehabilitation Environment with no perturbations and continuous, pseudo-random, mediolateral platform oscillations. Both the ranges and variability of angular momentum for both the whole body and both legs were significantly greater (p<0.001) during platform oscillations. There were no significant differences between groups in whole body angular momentum range or variability during unperturbed walking. The range of frontal plane angular momentum was significantly greater for those with amputation than for controls for all segments (p<0.05). For the whole body and intact leg, angular momentum ranges were greater for patients with amputation. However, for the prosthetic leg, angular momentum ranges were less for patients than controls. Patients with amputation were significantly more affected by the perturbations. Though patients with amputation were able to maintain similar patterns of whole body angular momentum during unperturbed walking, they were more highly destabilized by the walking surface perturbations. Individuals with transtibial amputation appear to predominantly use altered motion of the intact limb to maintain mediolateral stability. PMID:25797789

  1. The effects of standing balance in anteroposterior and mediolateral directions on knee strengthening in post-total knee replacement

    PubMed Central

    Lim, Sung-Joon; Cho, Sung-Hyoun; Nam, Gi-San

    2016-01-01

    [Purpose] The purpose of this study was to examine the association between muscle-strengthening exercises applied to the knee extensor muscles and the maintenance of standing balance in both, the anteroposterior and mediolateral directions in patients who had undergone total knee replacement. [Subjects and Methods] Thirty patients who underwent total knee replacement with bilateral artificial joints participated in this study. During the eight-week study period, the load on the knee extensors was gradually increased, and the standing balance ability was measured by differentiating the anteroposterior and mediolateral directions both, before and after the experimental period. [Results] In both, the anteroposterior and the mediolateral directions, there were statistically significant increases after the eight-week experiment, with a 29% increase in standing balance maintenance in the anteroposterior direction and a 22% increase in the mediolateral direction. [Conclusion] In patients who underwent bilateral total knee replacement, strengthening exercises applied to the knee extensor muscles with gradually increasing load positively affected standing balance in both anteroposterior and mediolateral directions. PMID:26957770

  2. Effects of narrow base gait on mediolateral balance control in young and older adults.

    PubMed

    Arvin, Mina; Mazaheri, Masood; Hoozemans, Marco J M; Pijnappels, Mirjam; Burger, Bart J; Verschueren, Sabine M P; van Dieën, Jaap H

    2016-05-01

    The aim of this study was to examine the effect of narrowing step width on mediolateral (ML) center of mass (COM) kinematics and margin of stability (MOS) in young and older adults. Fourteen young and 18 healthy older adults were asked to walk on a treadmill at preferred speed, stepping on projected lines at their predetermined preferred step width (PSW) and at a 50% narrowed step width (NSW). Linear trunk accelerations were recorded by an inertial sensor, attached at the level of the lumbar spine and foot placement was determined from force sensors in the treadmill. Mediolateral peak-to-peak COM displacement, COM velocity and MOS within strides were estimated. Mean ML-COM displacement and velocity, which were significantly higher in older compared to young adults, were significantly reduced in the NSW condition while the variability of ML-COM velocity was increased in the NSW condition. A significant interaction effect of step width and age was found for ML-COM velocity, showing larger decreases in older adults in the NSW condition. Walking with NSW reduced the ML-MOS significantly in both groups while it was smaller in the older group. Although reductions of ML-COM displacement and velocity may occur as direct mechanical effects of reduced step width, the larger variability of ML COM velocity in the older adults suggests active control of ML COM movements in response to the reduced base of support. Given the effects on MOS, narrowing step width might challenge ML-balance control and lead to less robust gait especially in older adults. PMID:27018156

  3. Can explicit visual feedback of postural sway efface the effects of sensory manipulations on mediolateral balance performance?

    PubMed

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

    2016-02-01

    Explicit visual feedback on postural sway is often used in balance assessment and training. However, up-weighting of visual information may mask impairments of other sensory systems. We therefore aimed to determine whether the effects of somatosensory, vestibular, and proprioceptive manipulations on mediolateral balance are reduced by explicit visual feedback on mediolateral sway of the body center of mass and by the presence of visual information. We manipulated sensory inputs of the somatosensory system by transcutaneous electric nerve stimulation on the feet soles (TENS) of the vestibular system by galvanic vestibular stimulation (GVS) and of the proprioceptive system by muscle-tendon vibration (VMS) of hip abductors. The effects of these manipulations on mediolateral sway were compared with a control condition without manipulation under three visual conditions: explicit feedback of sway of the body center of mass (FB), eyes open (EO), and eyes closed (EC). Mediolateral sway was quantified as the sum of energies in the power spectrum and as the energy at the dominant frequencies in each of the manipulation signals. Repeated-measures ANOVAs were used to test effects of each of the sensory manipulations, of visual conditions and their interaction. Overall, sensory manipulations increased body sway compared with the control conditions. Absence of normal visual information had no effect on sway, while explicit feedback reduced sway. Furthermore, interactions of visual information and sensory manipulation were found at specific dominant frequencies for GVS and VMS, with explicit feedback reducing the effects of the manipulations but not effacing these. PMID:26631143

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

    NASA Astrophysics Data System (ADS)

    Patthoff, D. A.; Kattenhorn, S. A.

    2010-12-01

    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 by numerous fractures. Overall, the trend of the dichotomy is semi-parallel to lines of latitude and has a shape that is roughly rectangular with the longer sides made of segments of the fold-like features. The parallel trend of some of the folds with the present day tiger stripes may be attributed to contraction to either side of the dilational tiger stripes. However, how the dichotomy has evolved, especially the older parts, and how the segments relate to the older fractures within the SPT remains unexplored. Our previous work has revealed an age sequence of fracture sets with similar properties to the tiger stripes. These fractures appear to have been rotated (clockwise, CW) about the south pole relative their original locations, which we attribute to long-term nonsynchronous rotation of a decoupled ice shell. The older sets include prominent fractures that are longer and wider than other fractures in each set and stand out as potentially ancient versions of the named tiger stripes. We have identified 7 potential paleo-tiger stripes that have a range of ages and orientations. The youngest of the paleo-tiger stripes are rotated ~28° CW relative to the orientation of the present day tiger stripes, the next oldest are rotated an additional ~47° CW, and the oldest another ~78° CW. If these paleo-tiger stripes were similar in form and function to the contemporary tiger stripes, localizing crustal spreading in the past, they should also have influenced the SPT dichotomy analogously to the present day tiger stripes. Accordingly, if the tiger stripes are responsible for fold belt-like features in the SPT dichotomy, the paleo-tiger stripes may have contributed to the creation of older fold belts in the dichotomy. These older fold belts should share similar ages and orientations to the fracture sets with which they are associated and may also have been modified as the ice shell rotated across a tidally-locked stress state. Our mapping shows that the youngest of the paleo-tiger stripes share a similar orientation to the fold belts of the dichotomy between longitudes of ~290° and 330° and near 90°. Additional correlations of the fold belts to older fracture sets likely exist. Other sections of the dichotomy are dominated by fractures instead of folds. The fractured terrains are centered near longitudes of 0° and 220° and spread out ~±25° longitude. The fractures are not randomly oriented but instead appear to have systematic sets, some of which correlate to the orientations of the paleo-tiger stripes. In order to establish a correlation with the paleo-tiger stripes we: 1) identify what specific structures comprise the dichotomy, 2) determine if different parts of the boundary have different ages by examining crosscutting relationships, 3) determine if sections of the dichotomy are genetically related to the fracture sets in the SPT, and 4) explore how the fracture sets interact with and influence the dichotomy.

  5. The dichotomy (generation of MAbs with functional heterogeneity) in antimalarial immune response in vaccinated/protected mice: a new concept in our understanding of the protective immune mechanisms in malaria.

    PubMed

    Singh, Prati Pal; Prakash, Bhanu

    2014-01-01

    Globally, vaccines have emerged as one of the most effective, safe, and cost-effective public health interventions, and are known to save 2-3 million lives, annually. However, despite various commendable efforts, a suitable human malaria vaccine is yet to see the light of the day. The lack of our complete understanding of the molecular mechanisms of pathogenesis and immune protection in malaria appears to be responsible for this state. Earlier, our laboratory has reported that Swiss mice vaccinated with Plasmodium yoelii nigeriensis-total parasite antigens soluble in culture medium and saponin, following a 100% lethal challenge, showed 60% protection. The monoclonal antibodies (MAbs) generated from the splenocytes of these vaccinated/protected mice, following characterization by in vitro merozoite invasion inhibition assay, ex vivo macrophage phagocytosis assay, and in vivo passive transfer of protection test, belonged to 2 distinct groups-a larger group of MAbs inhibited<58% Mz invasion and transferred 30% passive protection, whereas a smaller group of MAbs inhibited 86% Mz invasion and transferred 60% passive protection. Additionally, the MAbs of the smaller group, as compared with the larger one, mediated nearly 2.4-fold enhanced macrophage phagocytosis of infected-erythrocytes, in vitro. These results thus clearly showed a dichotomy among the generated MAbs. An exploration of the phenomenon of dichotomy in protective immunity in malaria by using various hosts and malaria parasite combinations, especially at the level of antibodies, cells, and cytokines, may add new insights to our understanding of the protective immunity, and help in the identification of biomarkers/biosignatures of immune protection and development of future human malaria vaccines. PMID:24632591

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

    PubMed Central

    2015-01-01

    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. PMID:25810755

  7. Interest of active posturography to detect age-related and early Parkinson's disease-related impairments in mediolateral postural control.

    PubMed

    Bonnet, Cédrick T; Delval, Arnaud; Defebvre, Luc

    2014-11-15

    Patients with Parkinson's disease display impairments of postural control most particularly in active, challenging conditions. The objective of the present study was to analyze early signs of disease-related and also age-related impairments in mediolateral body extension and postural control. Fifty-five participants (18 Hoehn and Yahr stage 2 patients in the off-drug condition, 18 healthy elderly control subjects, and 19 young adults) were included in the study. The participants performed a quiet stance task and two active tasks that analyzed the performance in mediolateral body motion: a limit of stability and a rhythmic weight shift task. As expected, the patients displayed significantly lower and slower body displacement (head, neck, lower back, center of pressure) than elderly control subjects when performing the two body excursion tasks. However, the behavioral variability in both tasks was similar between the groups. Under these active conditions, the patients showed significantly lower contribution of the hip postural control mechanisms compared with the elderly control subjects. Overall, the patients seemed to lower their performance in order to prevent a mediolateral postural instability. However, these patients, at an early stage of their disease, were not unstable in quiet stance. Complementarily, elderly control subjects displayed slower body performance than young adults, which therefore showed an additional age-related impairment in mediolateral postural control. Overall, the study illustrated markers of age-related and Parkinson's disease impairments in mediolateral postural control that may constrain everyday activities in elderly adults and even more in patients with Parkinson's disease. PMID:25143549

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

    SciTech Connect

    Engeland, Saskia van; Timp, Sheila; Karssemeijer, Nico

    2006-09-15

    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.

  9. Effects of Filtering the Center of Pressure Feedback Provided in Visually Guided Mediolateral Weight Shifting

    PubMed Central

    Kennedy, Michael W.; Crowell, Charles R.; Villano, Michael; Schmiedeler, James P.

    2016-01-01

    Thirty healthy adults completed a mediolateral weight-shifting balance task in which they were instructed to shift their weight to visually displayed target regions. A model-based filter and three different moving average filters employing 10, 34, and 58 samples were applied to the center of pressure visual feedback that guided the activity. The effects of filter selection on both the displayed feedback and the shift performance were examined in terms of shift time and non-minimum phase behavior. Shift time relates to feedback delay and shift speed, whereas non-minimum phase behavior relates to the force applied in shift initiation. Results indicated that increasing the number of samples in moving average filters (indicative of stronger filtering) significantly increases shift speed and shift initiation force. These effects indicate that careful selection and documentation of data filtering is warranted in future work and suggest opportunities for strategic filtering of visual feedback in clinical weight-shifting balance activities in order to improve outcomes based on such feedback. PMID:26991996

  10. Effects of Filtering the Center of Pressure Feedback Provided in Visually Guided Mediolateral Weight Shifting.

    PubMed

    Kennedy, Michael W; Crowell, Charles R; Villano, Michael; Schmiedeler, James P

    2016-01-01

    Thirty healthy adults completed a mediolateral weight-shifting balance task in which they were instructed to shift their weight to visually displayed target regions. A model-based filter and three different moving average filters employing 10, 34, and 58 samples were applied to the center of pressure visual feedback that guided the activity. The effects of filter selection on both the displayed feedback and the shift performance were examined in terms of shift time and non-minimum phase behavior. Shift time relates to feedback delay and shift speed, whereas non-minimum phase behavior relates to the force applied in shift initiation. Results indicated that increasing the number of samples in moving average filters (indicative of stronger filtering) significantly increases shift speed and shift initiation force. These effects indicate that careful selection and documentation of data filtering is warranted in future work and suggest opportunities for strategic filtering of visual feedback in clinical weight-shifting balance activities in order to improve outcomes based on such feedback. PMID:26991996

  11. The dichotomy of p53 regulation by noncoding RNAs

    PubMed Central

    Deng, Qipan; Becker, Lindsey; Ma, Xiaodong; Zhong, Xiaoming; Young, Ken; Ramos, Kenneth; Li, Yong

    2014-01-01

    The p53 tumor suppressor gene is the most frequently mutated gene in cancer. Significant progress has been made to discern the importance of p53 in coordinating cellular responses to DNA damage, oncogene activation, and other stresses. Noncoding RNAs are RNA molecules functioning without being translated into proteins. In this work, we discuss the dichotomy of p53 regulation by noncoding RNAs with four unconventional questions. First, is overexpression of microRNAs responsible for p53 inactivation in the absence of p53 mutation? Second, are there somatic mutations in the noncoding regions of the p53 gene? Third, is there a germline mutant in the noncoding regions of the p53 gene that predisposes carriers to cancer? Fourth, can p53 activation mediated by a noncoding RNA mutation cause cancer? This work highlights the prominence of noncoding RNAs in p53 dysregulation and tumorigenesis. PMID:24706938

  12. Dichotomies in Music Education--Real or Unreal?

    ERIC Educational Resources Information Center

    Espeland, Magne

    2010-01-01

    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,…

  13. Neither dichotomies nor dualisms; simply genesis.

    PubMed

    Loredo-Narciandi, José C; Sánchez-González, José C

    2012-09-01

    Our starting point is an article by Uchoa Angela Branco published in 2009 in Integrative Psychological and Behavioral Sciences (vol. 43, pp. 350-355) and titled "Why Dichotomies can be Misleading while Dualities Fit the Analysis of Complex Phenomena". She criticizes the dualist uses of the distinction between subject and object, or between subjectivist and objectivist perspectives. However we subscribe to the criticism, we argue that some kind of distinction between objectual and subjectual realities is neccesary. Our argument is grounded on the classic constructivist Psychology, especially that of James Mark Baldwin's genetic logic. We assess two theoretical perspectives -the systemic and the structuralist ones- that, in our view, are at risk of falling into objectivism because they tend to reduce subjectual activity to objectivistic or formalistic kinds of explanation. Based on a critical recovery of some ideas of the French philosopher Michel Serres, we propose that subjects and objects must be understood as interpenetrated realities in perpetual construction. PMID:22350852

  14. Dynamical Origins of the Kepler Dichotomy

    NASA Astrophysics Data System (ADS)

    Spalding, Christopher; Batygin, Konstantin

    2016-05-01

    An overabundance of single-transiting planetary systems relative to those with multiple transits within the Kepler dataset, has been interpreted as evidence for mutual inclinations between planetary orbits. The physical origins of this so-called "Kepler Dichotomy,” however, remain elusive. Here we show that the observed prevalence of single-planet systems is a direct consequence of secular evolution of initially planar multi-planet systems that orbit stars whose spin-axes are inclined with respect to the protoplanetary disks they host. Such primordial misalignments arise naturally within the disk-hosting stage by way of gravitational torques from stellar companions, and have been previously invoked as explanations for the commonness of spin-orbit misalignments in hot Jupiter systems. Accordingly, our model places the early dynamical evolution of hot super-Earths and hot Jupiters into a unified theoretical framework.

  15. Influence of temporal pressure on anticipatory postural control of medio-lateral stability during rapid leg flexion.

    PubMed

    Yiou, E; Hussein, T; Larue, J

    2012-03-01

    During leg flexion from erect posture, postural stability along the medio-lateral direction is organized in advance during "anticipatory postural adjustments" (APAs). This study aimed to investigate the influence of temporal pressure on this anticipatory postural control of medio-lateral stability. Eight young healthy participants performed series of leg flexions (1) as soon as possible in response to an acoustic signal (reaction-time condition; condition with temporal pressure) and (2) in a self-initiated condition (no temporal pressure). Results showed that APAs duration was shorter in the reaction-time condition as compared to the self-initiated condition; this shortening was compensated by an increase in the medio-lateral center-of-pressure displacement so that the dynamic stability reached at foot-off, as measured by the "extrapolated center-of-mass", remained unchanged. It is concluded that when a complex task is performed under temporal pressure, the central nervous system is able to modulate the spatio-temporal features of APAs in a way to both hasten the initiation of the voluntary movement and maintain optimal conditions of dynamic stability. In other words, it seems that the central nervous system does not "trade off optimal stability for speed of movement initiation under reaction-time condition", as it had been proposed in the literature. PMID:22153769

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

    PubMed Central

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

    2013-01-01

    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

  17. Effect of running speed and leg prostheses on mediolateral foot placement and its variability.

    PubMed

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

    2015-01-01

    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

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

    ERIC Educational Resources Information Center

    Lewkowicz, David J.

    2011-01-01

    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

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

    ERIC Educational Resources Information Center

    Lewkowicz, David J.

    2011-01-01

    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…

  20. CAN PLANETARY INSTABILITY EXPLAIN THE KEPLER DICHOTOMY?

    SciTech Connect

    Johansen, Anders; Davies, Melvyn B.; Church, Ross P.; Holmelin, Viktor

    2012-10-10

    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.

  1. Axial elongation in mouse embryos involves mediolateral cell intercalation behavior in the paraxial mesoderm

    NASA Astrophysics Data System (ADS)

    Yen, WeiWei; Burdsal, Carol; Periasamy, Ammasi; Sutherland, Ann E.

    2006-02-01

    The cell mechanical and signaling pathways involved in gastrulation have been studied extensively in invertebrates and amphibians, such as Xenopus, and more recently in non-mammalian vertebrates such as zebrafish and chick. However, because culturing mouse embryos extra-utero is very difficult, this fundamental process has been least characterized in the mouse. As the primary mammalian model for genetics, biochemistry, and the study of human disease and birth defects, it is important to investigate how gastrulation proceeds in murine embryos. We have developed a method of using 4D multiphoton excitation microscopy and extra-utero culture to visualize and characterize the morphogenetic movements in mouse embryos dissected at 8.5 days of gestation. Cells are labeled by expression of an X chromosome-linked enhanced green fluorescent protein (EGFP) transgene. This method has provided a unique approach, where, for the first time, patterns of cell behavior in the notochord and surrounding paraxial mesoderm can be visualized and traced quantitatively. Our observations of mouse embryos reveal both distinct differences as well as striking similarities in patterned cell motility relative to other vertebrate models such as Xenopus, where axial extension is driven primarily by mediolateral oriented cell behaviors in the notochord and paraxial somitic mesoderm. Unlike Xenopus, the width of the mouse notochord remains the same between 4-somite stage and 8-somite stage embryos. This implies the mouse notochord plays a lesser role in driving axial extension compared to Xenopus, although intercalation may occur where the anterior region of the node becomes notochordal plate. In contrast, the width of mouse paraxial mesoderm narrows significantly during this period and cells within the paraxial mesoderm are both elongated and aligned perpendicular to the midline. In addition, these cells are observed to intercalate, consistent with a role for paraxial mesoderm in driving convergence and extension. These cell behaviors are similar to those characterized in the axial mesoderm of frog embryos during convergence and extension[1], and suggests that tissues may play different roles in axial elongation between the frog and the mouse.

  2. Conceptual Fallacies in the Rural-Urban Dichotomy.

    ERIC Educational Resources Information Center

    Uzzell, Douglas

    1979-01-01

    Describes historical and contemporary social relations in the Oaxaca Valley, Mexico, in order to illustrate fallacies in the folk-urban dichotomy that arise when spatial distribution is treated as a cultural characteristic. (Author/GC)

  3. The Germanium Dichotomy in Martian Meteorites

    NASA Technical Reports Server (NTRS)

    Humayun, M.; Yang, S.; Righter, K.; Zanda, B.; Hewins, R. H.

    2016-01-01

    Germanium is a moderately volatile and siderophile element that follows silicon in its compatibility during partial melting of planetary mantles. Despite its obvious usefulness in planetary geochemistry germanium is not analyzed routinely, with there being only three prior studies reporting germanium abundances in Martian meteorites. The broad range (1-3 ppm) observed in Martian igneous rocks is in stark contrast to the narrow range of germanium observed in terrestrial basalts (1.5 plus or minus 0.1 ppm). The germanium data from these studies indicates that nakhlites contain 2-3 ppm germanium, while shergottites contain approximately 1 ppm germanium, a dichotomy with important implications for core formation models. There have been no reliable germanium abundances on chassignites. The ancient meteoritic breccia, NWA 7533 (and paired meteorites) contains numerous clasts, some pristine and some impact melt rocks, that are being studied individually. Because germanium is depleted in the Martian crust relative to chondritic impactors, it has proven useful as an indicator of meteoritic contamination of impact melt clasts in NWA 7533. The germanium/silicon ratio can be applied to minerals that might not partition nickel and iridium, like feldspars. We report germanium in minerals from the 3 known chassignites, 2 nakhlites and 5 shergottites by LAICP- MS using a method optimized for precise germanium analysis.

  4. Buried mass anomalies along the hemispheric dichotomy in eastern Mars: Implications for the origin and evolution of the dichotomy

    NASA Astrophysics Data System (ADS)

    Kiefer, Walter S.

    2005-11-01

    Gravity observations indicate the presence of buried, high-density material along the hemispheric dichotomy in eastern Mars. This material is unrelated to present-day topography and is probably the result of localized thinning of the crust. This thinning may be the result of an epoch of edge-driven convection that occurred shortly after the dichotomy formed. Initiation of edge-driven convection requires that lateral variations in lithospheric structure be created on a timescale that is shorter than the conductive cooling time for the lithosphere, a few tens of million years at most. This timescale cannot be achieved if the dichotomy boundary is created solely by large-scale convective flow. Formation or modification of the boundary by large impact basins such as Utopia can create the required lithospheric structure in a geologic instant. This suggests that large impacts were important in shaping the dichotomy, at least on a regional scale.

  5. Age-related challenges in reactive control of mediolateral stability during compensatory stepping: A focus on the dynamics of restabilisation.

    PubMed

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

    2016-03-21

    Age-related mediolateral instability during forward stepping reactions evoked by whole-body perturbation is believed to occur independent of the initial temporospatial parameters prior to step-contact. Recent research is beginning to explore the restabilisation phase, following step-contact, as the origin of such instability. This work sought to uncover potential mechanisms underlying age-related mediolateral instability during restabilisation by examining whole-body centre of mass (COM) kinematics and the orientation of the net ground reaction force relative to the COM. Healthy younger (n=20) and older adults (n=20) were anchored to a rigid frame, via adjustable cable. After establishing a standardised initial forward lean, cable release occurred with pseudorandom timing. Participants regained their balance using a single self-selected step. The potential for lateral instability was quantified by COM kinematics. The angle of divergence of the line of action of the net ground reaction force relative to the COM was quantified and examined at three discrete points during restabilisation, as indices of COM control. Age-related differences in magnitude and trial-to-trial variability were analysed. Older adults exhibited increased ML COM incongruity and trial-to-trial variability, which were reduced with trial repetition. Older adults required an increased time to reorient the net ground reaction force, which was correlated with the increased lateral COM displacement during restabilisation. The present results support the idea that age-related mediolateral instability occurs during restabilisation and may be linked to the reactive control of the orientation of the net ground reaction force with respect to the centre of mass. PMID:26920512

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

    NASA Technical Reports Server (NTRS)

    Guest, A.; Smrekar, S. E.

    2004-01-01

    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.

  7. Dawn: Testing Paradigms by Exploring Dichotomies

    NASA Astrophysics Data System (ADS)

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

    2010-12-01

    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.

  8. Topographic Change of the Dichotomy Boundary Suggested by Crustal Inversion

    NASA Technical Reports Server (NTRS)

    Neumann, G. A.

    2004-01-01

    Linear negative gravity anomalies in Acidalia Planitia along the eastern edge of Tempe Terra and along the northern edge of Arabia Terra have been noted in Mars Global Surveyor gravity fields. Once proposed to represent buried fluvial channels, it is now believed that these gravity troughs mainly arise from partial compensation of the hemispheric dichotomy topographic scarp. A recent inversion for crustal structure finds that mantle compensation of the scarp is offset from the present-day topographic expression of the dichotomy boundary. The offset suggests that erosion or other forms of mass wasting occurred after lithosphere thickened and no longer accomodated topographic change through viscous relaxation.

  9. Beyond Dichotomy: Toward a Theory of Divergence in Composition Studies.

    ERIC Educational Resources Information Center

    Bawarshi, Anis S.

    1997-01-01

    Examines the dichotomy posited by David Bartholmae and Peter Elbow between institutional or contextual writing and personal writing; or more generally, between social constructivism and expressivism. Attempts to propose a means of mediation between the two positions that goes beyond previous attempts, particularly that of "externalism." (TB)

  10. False Dichotomy? "Western" and "Confucian" Concepts of Scholarship and Learning

    ERIC Educational Resources Information Center

    Ryan, Janette; Louie, Kam

    2007-01-01

    Discourses of "internationalisation" of the curriculum of Western universities often describe the philosophies and paradigms of "Western" and "Eastern" scholarship in binary terms, such as "deep/surface", "adversarial/harmonious", and "independent/dependent". In practice, such dichotomies can be misleading. They do not take account of the

  11. Direct Instruction vs. Arts Integration: A False Dichotomy

    ERIC Educational Resources Information Center

    Aprill, Arnold

    2010-01-01

    In this article, the author takes on what he considers to be the false dichotomy between direct instruction and arts integration. He contends that at a time when national issues of sustainability and conservation of energy and resources become ever more urgent, it is time that those committed to quality arts education stop squandering time, money,

  12. Direct Instruction vs. Arts Integration: A False Dichotomy

    ERIC Educational Resources Information Center

    Aprill, Arnold

    2010-01-01

    In this article, the author takes on what he considers to be the false dichotomy between direct instruction and arts integration. He contends that at a time when national issues of sustainability and conservation of energy and resources become ever more urgent, it is time that those committed to quality arts education stop squandering time, money,…

  13. Education and Care: Revisiting the Dichotomy.

    ERIC Educational Resources Information Center

    Sims, Margaret

    1994-01-01

    Examines the stated goals and outcomes of early childhood and child care programs. Uses a functional perspective in which actual outcomes are analyzed as functions to compare child care with early childhood education. Discusses the ideology of each type of program and examines the positive and negative aspects of amalgamating early childhood care…

  14. Generation and vulnerability of deep cerebellar nuclei neurons in the weaver condition along the anteroposterior and mediolateral axes.

    PubMed

    Martí, Joaquín; Santa-Cruz, M C; Hervás, José P

    2016-04-01

    Production and death of deep cerebellar nuclei (DCN) neurons were investigated in the weaver condition at appropriate anatomical levels throughout the mediolateral (medial, intermediate and lateral) and rostrocaudal (rostral, middle and caudal) axes of three DCN-cell groups: the fastigial, the interposed and the dentate nuclei. Current results have denoted that the deficit of DCN neurons is always more important in the homozygous weaver than in the heterozygous weaver mice. No loss of neurons was found in the dentate nucleus. In the mediolateral axis, an intranuclear gradient of depletion was observed in the mutant mice; in a given deep nucleus, neurodegeneration was more prominent in the medial pars than in lateral ones. In the rostrocaudal axis, on the other hand, when each deep nucleus was studied and compared as a whole, neuron loss was higher in the fastigial nucleus than in the interposed nucleus, which, in turn, was more important than in the dentate nucleus. These data suggest that, in the weaver condition, an internuclear gradient of neurodegeneration exists. Moreover, neurons located in rostral parts of a given nucleus appear to be more vulnerable than those settled in middle parts and these, in turn, are more than the caudal ones. These results seem to indicate the presence of an intranuclear gradient of depletion. Current autoradiographic results have revealed that, in the rostrocaudal axis, deep neurons are settled in the weaver cerebellum following three neurogenetic gradients. The first of these is internuclear; if each deep nucleus is analyzed and compared as a whole, the fastigial nucleus has more late-generated neurons than the interposed nucleus, and this, in turn, has more than the dentate nucleus. The second gradient is also internuclear; if the proportion of late-born neurons is compared throughout the rostral levels from each deep nucleus, it is observed that proportions increase from the fastigial to the dentate nucleus. A similar picture emerges when the middle and caudal regions are taken into account. The third gradient is intranuclear; in a given deep nucleus, the rostral region always presents more late-produced neurons than the middle region and these, in turn, more than in the caudal level. PMID:26748014

  15. The Biological Implausibility of the Nature-Nurture Dichotomy & What It Means for the Study of Infancy

    PubMed Central

    Lewkowicz, David J.

    2011-01-01

    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 powerful effect on our thinking about development right into modern times. Despite this, empirical findings from various branches of developmental science have made a compelling case that the nature/nurture dichotomy is biologically implausible and, thus, that a search for developmental origins must be replaced by research into developmental processes. This change in focus recognizes that development is an immensely complex, dynamic, embedded, interdependent, and probabilistic process and, therefore, renders simplistic questions such as whether a particular behavioral capacity is innate or acquired scientifically uninteresting. PMID:21709807

  16. Dichotomy of Solar Coronal Jets: Standard Jets and Blowout Jets

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    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.

  17. DICHOTOMY OF SOLAR CORONAL JETS: STANDARD JETS AND BLOWOUT JETS

    SciTech Connect

    Moore, Ronald L.; Cirtain, Jonathan W.; Sterling, Alphonse C.; Falconer, David A.

    2010-09-01

    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.

  18. On the dichotomy in the Earth-Moon system restricted three-body problem

    NASA Astrophysics Data System (ADS)

    Safiya Beevi, A.; Sharma, R. K.

    2012-10-01

    We apply the numerical technique of Poincare surface of section to investigate the dichotomy present in the Earth-Moon system, considering the framework of planar, circular, restricted three-body problem. A study on the transition of quasi-periodic orbits (oscillatory type dichotomy) present at the Jacobi constant C=2.85 shows that the dichotomy discussed here exist not at a particular value of the mass ratio and the Jacobi constant. It is observed that as C increases, the range of mass ratio at which the dichotomy pertains increases, even though the mass ratio at which the transition of orbits takes place decreases.

  19. The geophysical signal of the martian global dichotomy

    NASA Technical Reports Server (NTRS)

    Phillips, Roger J.

    1992-01-01

    A first-order tectonic question for Mars is the origin and nature of the global dichotomy (GD) separating approximately the northern and southern hemispheres of the planet. It is appropriate to focus on hypotheses for the origin of the GD as well as on geophysical models of related internal structure that are constrained by present-day observations. There are basic planetary scale observations that relate to the GD: (1) the dichotomy boundary separates two fundamentally different elevations on the planet, as the terrain to the north is lower by an average of about 3 km; (2) the boundary separates terrain of regionally distinct crater ages, heavily cratered (older) in the south and sparsely cratered (younger) in the north; (3) the amount of ancient crust apparently removed from north of the dichotomy boundary cannot be accounted for by simple surface erosion and deposition in the south, and the constraint becomes particularly severe if isostatic adjustment is presumed to have accompanied this process. This last point leads to the supposition that some type of interior process must have been responsible for the creation of the GD. An obvious way to create the observed elevation difference between the two hemispheres is with a thinner crust in the north, although a denser cust would also work. Hypotheses for producing a thinner northern crust include preferential sub-crustal erosion, a giant impact, and simply invoking the crustal thickness difference as a primordial feature of the planet. If the GD represents a fundamental change in the crustal thickness of Mars, then there should be geophysical evidence of this. The center-of-figure to center-of-mass offset of the planet may be related to the GD, but the Tharsis topography must certainly also contribute. If the Tharsis and GD effects can be separated, then a crustal thickness model can be tested, though the results will not be unique. The gravity field provides another geophysical constraint on GD models. A simple change in thickness of an isostatically compensated crust should show a characteristic gravity signal across the dichotomy boundary. There is a gravity anomaly that is clearly associated with the boundary in regions where the gravity signal is not cluttered by contributions from other features such as Tharsis and Elysium. The gravity signal has a complex spatial relationship with the boundary, and efforts are presently underway to model this anomaly.

  20. Will The Kraepelinian Dichotomy Survive DSM-V?

    PubMed Central

    Fischer, Bernard A.; Carpenter, William T.

    2009-01-01

    Kraepelin proposed dementia praecox and manic-depressive illness as the two major psychotic disorders. This paradigm is still prevalent, but observations of overlapping boundaries between bipolar disorder and schizophrenia challenge this dichotomy. However, the concept of schizophrenia has been radically altered from the original Kraepelinian proposal. We defend the two psychoses position, but suggest two flaws in the heuristic application: 1) overlapping features such as psychotic symptoms are not decisive in differential diagnosis; and 2) each disorder is a syndrome, not a disease entity. An alternative paradigm based on domains of pathology is more powerful for studies of etiology, pathophysiology, and therapeutic discovery. PMID:19295511

  1. Dichotomy of some satellites of the outer Solar system

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2011-10-01

    Recently acquired by the Cas as ini' CIR a temperature map (11 -16 microns radiation) of small satellite Mimas caused a perplexity among the Cassini scientists (an interpretation of PIA12867). They expected to have a regular temperature map characteristic of a homogeneous spherical body heated by Sun. Instead, the bizarre map with two sharply divided temperature fields was produced (Fig. 1). The temperature difference between two fields is about 15 Kelvin that is rather remarkable. The warm part has typical temperature near 92 Kelvin, the cold part -about 77 Kelvin. Obviously there are two icy substances with different conductivity of heat composing two planetary segments (hemispheres). But in this result there is nothing new for explorers insisting for many years that all celestial bodies are tectonically dichotomous [1, 2, 3]. However, this new beautiful confirmat ion of the wave planetology theorem 1 (" Celes tial bodies are dichotomous ") is not s uperfluous , as many s cientis ts , es pecially in the USA, are not acquainted with the wave p lanetology. The fundamental wave 1 long 2πR warping any body aris es in them becaus e they move in elliptica l keple rian orbits with periodically changing acceleration. Having in rotating bodies (but all bodies rotate!) a stationary character and four interfering directions (ortho- and diagonal) these waves inevitably produce uplifting (+), subsiding (-), and neutral (0) tectonic blocks (Fig. 7). The uplifts and subsidences are in an opposition (the best examples are the terrestrial Eastern (+) and Western ( -) segments-hemispheres and mart ian Northern (-) and Southern (+) ones) [3]. The small icy Mimas (396 km in diameter) is no exclusion (Fig. 1). Its dichotomy is well pronounced in two temperature fields obviously reflect ing slightly different in composition icy materials composing two segments. Presence of two kinds of surface materials is also revealed by spectrometry under combination of the UV, green and IR emissions (Fig. 4). Around Herschel Crater material is more bluish than more greenish elsewhere (artificial colors). Presence of dark streaks on walls o f some craters also indicates at another than pure ice substance. The deep Herschel Crater on the cooler segment is somewhat warmer than surrounding terrains (Fig. 1). Thus, one may suppose that the warmer segment exposes deeper layers and is uplifted (+), the cooler segment is subsided (-). Important confirmat ions of Mimas ' dichotomy are s imi lar geometric patterns observed on Iapetus (black & white) (Fig. 2) and on Titania (Fig. 3). Such pattern can be caught under specific viewing point s of dichotomous structure. Figures 5 and 6 show dichotomies of Rhea and Dione. Fig. 7 gives a geometrical s cheme of getting dichotomies by wave interference.

  2. Beyond the dichotomy: six religious views of homosexuality.

    PubMed

    Moon, Dawne

    2014-01-01

    Using published theological and scholarly evidence, this article disrupts the stereotypical "born gay"/"sinful choice" dichotomy widely assumed to characterize religious views of homosexuality in the United States. It argues that we need to keep moral questions separate from questions about the fixity or fluidity of sexual orientation. Rather than two, American Christian and Jewish views of homosexuality can been seen on a range from the "God Hates Fags" view through "Love the Sinner, Hate the Sin," "We Don't Talk About That," "They Can't Help It," "God's Good Gift," and a queer-theological view of the "Godly Calling." PMID:24871867

  3. The Prokaryote-Eukaryote Dichotomy: Meanings and Mythology

    PubMed Central

    Sapp, Jan

    2005-01-01

    Drawing on documents both published and archival, this paper explains how the prokaryote-eukaryote dichotomy of the 1960s was constructed, the purposes it served, and what it implied in terms of classification and phylogeny. In doing so, I first show how the concept was attributed to Edouard Chatton and the context in which he introduced the terms. Following, I examine the context in which the terms were reintroduced into biology in 1962 by Roger Stanier and C. B. van Niel. I study the discourse over the subsequent decade to understand how the organizational dichotomy took on the form of a natural classification as the kingdom Monera or superkingdom Procaryotae. Stanier and van Niel admitted that, in regard to constructing a natural classification of bacteria, structural characteristics were no more useful than physiological properties. They repeatedly denied that bacterial phylogenetics was possible. I thus examine the great historical irony that the “prokaryote,” in both its organizational and phylogenetic senses, was defined (negatively) on the basis of structure. Finally, we see how phylogenetic research based on 16S rRNA led by Carl Woese and his collaborators confronted the prokaryote concept while moving microbiology to the center of evolutionary biology. PMID:15944457

  4. Hydrophobic–hydrophilic dichotomy of the butterfly proboscis

    PubMed Central

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

    2013-01-01

    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

  5. Hydrophobic-hydrophilic dichotomy of the butterfly proboscis.

    PubMed

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

    2013-08-01

    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

  6. Going and stopping: dichotomies in behavioral control by the prefrontal cortex.

    PubMed

    Gourley, Shannon L; Taylor, Jane R

    2016-04-26

    The rodent dorsal medial prefrontal cortex (PFC), specifically the prelimbic cortex (PL), regulates the expression of conditioned fear and behaviors interpreted as reward seeking. Meanwhile, the ventral medial PFC, namely the infralimbic cortex (IL), is essential to extinction conditioning in both appetitive and aversive domains. Here we review evidence that supports, or refutes, this "PL-go/IL-stop" dichotomy. We focus on the extinction of conditioned fear and the extinction and reinstatement of cocaine- or heroin-reinforced responding following abstinence. We then synthesize evidence that the PL is essential for developing goal-directed response strategies, while the IL supports habit behavior. Finally, we propose that some functions of the orbital PFC parallel those of the medial PFC in the regulation of response selection. Integration of these discoveries may provide points of intervention for inhibiting untethered drug seeking in drug use disorders, extinction failures in post-traumatic stress disorder, or co-morbidities between the two. PMID:27116390

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

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  8. Knowledge of Being v. Practice of Becoming in Higher Education: Overcoming the Dichotomy in the Humanities

    ERIC Educational Resources Information Center

    Marquez, Ivan

    2006-01-01

    This essay suggests ways to overcome what I take to be a widespread problem of a dichotomy between the knowledge of being and the practice of becoming and an emphasis on the former at the expense of the latter within contemporary Humanities at the university. First, I trace the genealogy of this dichotomy and its effects on contemporary

  9. The Borealis basin and the origin of the martian crustal dichotomy.

    PubMed

    Andrews-Hanna, Jeffrey C; Zuber, Maria T; Banerdt, W Bruce

    2008-06-26

    The most prominent feature on the surface of Mars is the near-hemispheric dichotomy between the southern highlands and northern lowlands. The root of this dichotomy is a change in crustal thickness along an apparently irregular boundary, which can be traced around the planet, except where it is presumably buried beneath the Tharsis volcanic rise. The isostatic compensation of these distinct provinces and the ancient population of impact craters buried beneath the young lowlands surface suggest that the dichotomy is one of the most ancient features on the planet. However, the origin of this dichotomy has remained uncertain, with little evidence to distinguish between the suggested causes: a giant impact or mantle convection/overturn. Here we use the gravity and topography of Mars to constrain the location of the dichotomy boundary beneath Tharsis, taking advantage of the different modes of compensation for Tharsis and the dichotomy to separate their effects. We find that the dichotomy boundary along its entire path around the planet is accurately fitted by an ellipse measuring approximately 10,600 by 8,500 km, centred at 67 degrees N, 208 degrees E. We suggest that the elliptical nature of the crustal dichotomy is most simply explained by a giant impact, representing the largest such structure thus far identified in the Solar System. PMID:18580944

  10. Roughness of (ℤ+, ℤ−)-Nonuniform Exponential Dichotomy for Difference Equations in Banach Spaces

    PubMed Central

    2014-01-01

    In this paper we study the roughness of (ℤ+, ℤ−)-nonuniform exponential dichotomy for nonautonomous difference equations in the general context of infinite-dimensional spaces. An explicit form is given for each of the dichotomy constants of the perturbed equation in terms of the original ones. We emphasize that we do not assume any boundedness condition on the coefficients. PMID:24592188

  11. Overcoming the dichotomy of quantity and quality in antibody responses.

    PubMed

    Meyer-Hermann, Michael

    2014-12-01

    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

  12. The Albedo Dichotomy of Iapetus Measured at UV Wavelengths

    NASA Technical Reports Server (NTRS)

    Hendrix, Amanda R.; Hansen, Candice J.

    2007-01-01

    The dramatic hemispheric dichotomy in albedo displayed by Saturn's moon Iapetus has intrigued astronomers for centuries. Here we report on far-ultraviolet observations of Iapetus' bright and dark terrains from Cassini. We compare the reflectance spectra of Iapetus's dark terrain, Hyperion and Phoebe and find that both Phoebe and Hyperion are richer in water ice than Iapetus' dark terrain. Spectra of the lowest latitudes of the dark terrain display the diagnostic water ice absorption feature; water ice amounts increase within the dark material away from the apex (at 90 deg W longitude, the center of the dark leading hemisphere), consistent with thermal segregation of water ice. The water ice in the darkest, warmest low latitude regions is not expected to be stable and may be a sign of ongoing or recent emplacement of the dark material from an exogenic source.

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

    NASA Technical Reports Server (NTRS)

    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

    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.

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

    NASA Technical Reports Server (NTRS)

    2004-01-01

    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.

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

    PubMed Central

    Adair, Linda S

    2007-01-01

    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

  16. Dichotomy of X-Ray Jets in Solar Coronal Holes

    NASA Astrophysics Data System (ADS)

    Robe, D. M.; Moore, R. L.; Falconer, D. A.

    2012-12-01

    It has been found that there are two different types of X-ray jets observed in the Sun's polar coronal holes: standard jets and blowout jets. A proposed model of this dichotomy is that a standard jet is produced by a burst of reconnection of the ambient magnetic field with the opposite-polarity leg of the base arcade. In contrast, it appears that a blowout jet is produced when the interior of the arcade has so much pent-up free magnetic energy in the form of shear and twist in the interior field that the external reconnection unleashes the interior field to erupt open. In this project, X-ray movies of the polar coronal holes taken by Hinode were searched for X-ray jets. Co-temporal movies taken by the Solar Dynamics Observatory in 304 Å emission from He II, showing solar plasma at temperatures around 80,000 K, were examined for whether the identified blowout jets carry much more He II plasma than the identified standard jets. It was found that though some jets identified as standard from the X-ray movies could be seen in the He II 304 Å movies, the blowout jets carried much more 80,000 K plasma than did most standard jets. This finding supports the proposed model for the morphology and development of the two types of jets.

  17. 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)

    Gilmore, M. S.

    1999-01-01

    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.

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

    PubMed

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

    2014-02-01

    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 57.114.1; ACLR 75.117.8; CONT 77.714.07% height). ACLR used a similar kinematic strategy to CONT, but had a reduced peak knee extensor moment (p<0.001; ACLD 0.320.14; ACLR 0.310.16; CONT 0.420.13 BW.height). Fluency was reduced in both ACLD and ACLR (p=0.006; ACLD 0.130.34; ACLR 0.140.34; CONT 0.170.41s). 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

  19. The magnetic dichotomy of the Galilean satellites Europa and Ganymede

    NASA Astrophysics Data System (ADS)

    Breuer, D.; Spohn, T.

    One of the most surprising discoveries of the Galileo mission was the detection of a self-generated magnetic field in the vicinity of Ganymede. Up to that discovery, it was widely believed that Ganymede did not fully differentiate and had a central region composed of silicates and iron and an outer ice layer. The existence of the self-generated magnetic field together with the relatively small value of the moment-of-inertia factor, suggests that Ganymede is strongly differentiated into an iron core, a silicate mantle and an outer ice layer. Based on Galileo gravity field measurements, a similar interior structure has been proposed for Europa where an internal magnetic field is absent. It has been suggested that chemical convection due to the precipitation of iron or iron sulfide is the most likely mechanism to power a present-day dynamo on Ganymede. Chemical convection and dynamo action will start as soon as core temperatures fall below the liquidus temperature of the core alloy and operates as long as the core is cooling. Interestingly, although Ganymede is about 700 km larger in radius than Europa, the differences in size and mass of the silicate and iron part, respectively, are only small for both satellites. As a consequence, one would expect a similar thermal and magnetic field evolution in both cases. However, thermal evolution models indicate that it is even more likely for Europa to generate an internal field if the same set of parameter values for mantle rheology and radioactive heat source density is used as for Ganymede. We will discuss two scenarios that may help explain the puzzling magnetic dichotomy between both satellites: (1) a larger content of light elements in the core of Europa as compared to Ganymede and (2) tidal heating in the silicate mantle of Europa.

  20. Phenotypic dichotomy in mitochondrial complex II genetic disorders.

    PubMed

    Baysal, B E; Rubinstein, W S; Taschner, P E

    2001-09-01

    This review presents our current knowledge on the genetic and phenotypic aspects of mitochondrial complex II gene defects. The mutations of the complex II subunits cause two strikingly different group of disorders, revealing a phenotypic dichotomy. Genetic disorders of the mitochondrial respiratory chain are often characterized by hypotonia, growth retardation, cardiomyopathy, myopathy, neuropathy, organ failure, and metabolic derangement. These disorders are transmitted through maternal lineage if the defective gene is located in the mitochondrial genome or may follow a Mendelian pattern if it is in the nucleus. Mitochondrial complex II (succinate:ubiquinone oxidoreductase) is the smallest complex in the respiratory chain and is composed of four subunits encoded by nuclear genes SDHA, SDHB, SDHC, and SDHD. Complex II oxidizes succinate to fumarate in the Krebs cycle and is involved in the mitochondrial electron transport chain. SDHA and SDHB encode the flavoprotein and iron-sulfur proteins, respectively, and SDHC and SDHD encode the two hydrophobic membrane-spanning subunits. While mutations in SDHA display a phenotype resembling other mitochondrial and Krebs cycle gene defects, those in SDHB, SDHC and SDHD cause hereditary paraganglioma. Paraganglioma is characterized by slow-growing vascular tumors of the paraganglionic tissue (i.e., adrenal and extra-adrenal paragangliomas, including those in the head and neck, mediastinum, abdomen, and pheochromocytomas). Paraganglioma caused by SDHD mutations occurs exclusively after paternal transmission, suggesting that genomic imprinting influences gene expression. Association of a mitochondrial gene defect with tumorigenesis expands the phenotypic spectrum of mitochondrial diseases and adds genomic imprinting as a new transmission mode in mitochondrial genetics. The phenotypic features of complex II gene mutations suggest that whereas the catalytic subunit SDHA mutations may compromise the Krebs cycle, those in other structural subunits may affect oxygen sensing and signaling. PMID:11692162

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

    PubMed

    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

    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

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

    NASA Technical Reports Server (NTRS)

    Guest, A.; Smrekar, S. E.

    2005-01-01

    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].

  3. Relaxation of the Martian Crustal Dichotomy Boundary in the Ismenius Region

    NASA Technical Reports Server (NTRS)

    Guest, A.; Smrekar, S. E.

    2004-01-01

    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].

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

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    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].

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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.

  6. Continuous Time Random Walk and Migration-Proliferation Dichotomy of Brain Cancer

    NASA Astrophysics Data System (ADS)

    Iomin, A.

    2015-10-01

    A theory of fractional kinetics of glial cancer cells is presented. A role of the migration-proliferation dichotomy in the fractional cancer cell dynamics in the outer-invasive zone is discussed and explained in the framework of a continuous time random walk. The main suggested model is based on a construction of a 3D comb model, where the migration-proliferation dichotomy becomes naturally apparent and the outer-invasive zone of glioma cancer is considered as a fractal composite with a fractal dimension Dfr < 3.

  7. Continuous Time Random Walk and Migration-Proliferation Dichotomy of Brain Cancer

    NASA Astrophysics Data System (ADS)

    Iomin, A.

    A theory of fractional kinetics of glial cancer cells is presented. A role of the migration-proliferation dichotomy in the fractional cancer cell dynamics in the outer-invasive zone is discussed and explained in the framework of a continuous time random walk. The main suggested model is based on a construction of a 3D comb model, where the migration-proliferation dichotomy becomes naturally apparent and the outer-invasive zone of glioma cancer is considered as a fractal composite with a fractal dimension Dfr < 3.

  8. Radiowaves and Tectonic Dichotomy: Two Sides of One Coin

    NASA Astrophysics Data System (ADS)

    Kochemasov, G.

    The first theorem of the wave planetology states that "Celestial bodies are di- chotomic"[1]. This notion is best demonstrated by modulation of the high frequency orbiting in the Solar system (SS) by the low frequency orbiting the SS in Galaxy. Or- biting frequencies of all bodies in the SS -from 1/8 hours for Phobos to 1/248 years for Pluto - are high comparative to the SS orbiting in Galaxy -about 1/200 000 000 years. Modulation of a high frequency by a low frequency brings about side frequencies at both sides of a high frequency. Earlier we considered only one side of the modula- tion stressing that the lower side frequency in any celestial body can achieve only the fundamental wave and produce related to it inevitable tectonic dichotomy [2]. Now we consider the higher side frequencies and find that they are in the limits of the ra- dio frequencies. Dividing all possible orbiting frequencies of bodies in the SS by the SS orbiting frequency in Galaxy one comes to a range of side frequencies from mi- crowaves to kilometer waves. This finding is rather important as it is well known that all bodies of the SS emit often enigmatic radiowaves. Figuratively, the SS is wrapped by a cloud of crossing radiowaves of various frequencies. Some calculations below show modulation of tectonic granula sizes of some celestial bodies. A granula size is a half of a wavelength which is tied to an orbiting frequency. A scale is the Earth's orbiting period 1 year and the granula size pR/4. The tectonic granula sizes of bodies are proportional to their orbital periods (Theorem 3 [1[). The modulating frequency is 1/200 000 000 years. Jupiter (12 y : 200 000 000 y) pR= (12 : 200 000 000) 3.14°u 71400 km=13.4 m tectonic granula or 26.8 m wavelength. Varying orbital periods and bodies'radia one comes to the following wavelengths. Jupiter-26.8 m, Saturn-56.4 m, Uranus-67 m, Neptune-124 m, Pluto-10.9 m, Sun-1.46 m, Triton-11.4 m (for the cir- cumsolar frequency), 1.84 mm (circumneptunian fr.), Amalthea-4.88 cm (circumsolar fr.), 0.0028 mm (circumjovian fr.), the Moon-5.46 cm (circumsolar fr.), 0.46 cm (cir- cumterrestrial fr.) [3]. This range of frequencies (infrared-kilometer waves) is typical for the SS. Within it surely there are waves of other modulations, harmonics, reso- nances. Extra heat emissions of Amalthea, Io, Triton could be related to microwave and infrared emissions (oscillations). References. [1] Kochemasov G.G.(1999) Geophys. Res. Abstr., v.1, #3.700; [2]Kochemasov G.G. (2000) 32nd Vernadsky-Brown microsymp. on comparative planetology, Abstr.,Moscow, 88-89; [3]Kochemasov G.G. (2001) 34th Vernadsky-Brown microsymp. Topics in comparative planetology, Ab- str., Moscow,(CD-ROM).

  9. Electron dichotomy on the SrTiO3 defect surface augmented by many-body effects

    NASA Astrophysics Data System (ADS)

    Lechermann, Frank; Jeschke, Harald O.; Kim, Aaram J.; Backes, Steffen; Valentí, Roser

    2016-03-01

    In a common paradigm, the electronic structure of condensed matter is divided into weakly and strongly correlated compounds. While conventional band theory usually works well for the former class, many-body effects are essential for the latter. Materials such as the familiar SrTiO3 (STO) compound that bridge or even abandon this characterization scheme are highly interesting. Here, it is shown, by means of combining density functional theory with dynamical mean-field theory, that oxygen vacancies on the STO (001) surface give rise to a dichotomy of weakly correlated t2 g low-energy quasiparticles and localized "in-gap" states of dominant eg character with a subtle correlation signature. We furthermore touch base with recent experimental work and study the surface instability towards magnetic order.

  10. The Dichotomy of Endoplasmic Reticulum Stress Response in Liver Ischemia-Reperfusion Injury.

    PubMed

    Zhou, Haomming; Zhu, Jianjun; Yue, Shi; Lu, Ling; Busuttil, Ronald W; Kupiec-Weglinski, Jerzy W; Wang, Xuehao; Zhai, Yuan

    2016-02-01

    Endoplasmic reticulum (ER) stress plays critical roles in the pathogenesis of liver ischemia-reperfusion injury (IRI). As ER stress triggers an adaptive cellular response, the question of what determines its functional outcome in liver IRI remains to be defined. In a murine liver partial warm ischemia model, we studied how transient (30 minutes) or prolonged (90 minutes) liver ischemia regulated local ER stress response and autophagy activities and their relationship with liver IRI. Effects of chemical chaperon 4-phenylbutyrate (4-PBA) or autophagy inhibitor 3-methyladenine (3-MA) were evaluated. Our results showed that although the activating transcription factor 6 branch of ER stress response was induced in livers by both types of ischemia, liver autophagy was activated by transient, but inhibited by prolonged, ischemia. Although 3-MA had no effects on liver IRI after prolonged ischemia, it significantly increased liver IRI after transient ischemia. The 4-PBA treatment protected livers from IRI after prolonged ischemia by restoring autophagy flux, and the adjunctive 3-MA treatment abrogated its liver protective effect. The same 4-PBA treatment, however, increased liver IRI and disrupted autophagy flux after transient ischemia. Although both types of ischemia activated 5' adenosine monophosphate-activated protein kinase and inactivated protein kinase B (Akt), prolonged ischemia also resulted in downregulations of autophagy-related gene 3 and autophagy-related gene 5 in ischemic livers. These results indicate a functional dichotomy of ER stress response in liver IRI via its regulation of autophagy. Transient ischemia activates autophagy to protect livers from IRI, whereas prolonged ischemia inhibits autophagy to promote the development of liver IRI. PMID:26683513

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

    PubMed

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

    2013-07-01

    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

  12. A NOVEL METHOD TO QUANTIFY HISTOCHEMICAL CHANGES THROUGHOUT THE MEDIOLATERAL AXIS OF THE SUBSTANTIA GELATINOSA AFTER SPARED NERVE INJURY: CHARACTERIZATION WITH TRPV1 AND SUBSTANCE P

    PubMed Central

    Corder, G.; Siegel, A.; Intondi, A.B.; Zhang, X.; Zadina, J.E.; Taylor, B.K.

    2010-01-01

    Nerve injury dramatically increases or decreases protein expression in the spinal cord dorsal horn. Whether the spatial distribution of these changes is restricted to the central innervation territories of injured nerves or could spread to adjacent territories in the dorsal horn is not understood. To address this question, we developed a simple computer software-assisted method to precisely distinguish and efficiently quantify immunohistochemical staining patterns across the mediolateral axis of the dorsal horn 2 wk after transection of either the tibial and common peroneal nerves (thus sparing the sural branch, spared nerve injury, SNI), the tibial nerve, or the common peroneal and sural nerves. Using thiamine monophosphatase (TMP) histochemistry, we determined that central terminals of the tibial, common peroneal, sural, and posterior cutaneous nerves occupy the medial 35%, medial-central 20%, central-lateral 20%, and lateral 25% of the substantia gelatinosa, respectively. We then used these calculations to show that SNI reduced the expression of SP and TRPV1 immunoreactivity within the tibial and peroneal innervation territories in the L4 dorsal horn, without changing expression in the uninjured, sural sector. We conclude that SNI-induced loss of SP and TRPV1 in central terminals of dorsal horn is restricted to injured fibers. Our new method enables direct comparison of injured and uninjured terminals in the dorsal horn so as to better understand their relative contributions to mechanisms of chronic pain. PMID:20350706

  13. Geomorphology of the Martian Crustal Dichotomy Boundary: Implications for Age and Origin

    NASA Astrophysics Data System (ADS)

    Irwin, R. P.; Watters, T. R.

    2005-12-01

    The fairly abrupt decline in surface age, elevation, and crustal thickness from the southern highlands to the northern lowlands of Mars is termed the crustal dichotomy. The cause of northern crustal thinning remains among the major unresolved issues in Mars research. Most geophysical models have invoked degree-1 mantle convection, whereas others suggest plate tectonism or one or more giant impacts in the northern hemisphere. Other studies have focused on modifications to the highland/lowland dichotomy boundary, which may or may not be relevant to the issue of origin. These hypotheses include erosion, extensional faulting, lateral crustal flow, and flexure of an elastic lithosphere by loading of the lowlands. The geomorphology of the highland/lowland boundary region provides important controls for these geophysical models of early crustal development. Geologic observations suggest that the thin lowland crust and dichotomy boundary originated in the Early Noachian Epoch (>4 Ga). The slope within ancient cratered terrain along the boundary influenced post-Noachian fresh crater morphology, Late Noachian valley network planform, and the degradation of Middle to Late Noachian (~3.95-3.7 Ga) impact craters. For fresh (post-Noachian) craters emplaced on the dichotomy slope, the plane of the rim crest inclines subparallel to the exterior slope, although the interior cavity and central peak are oriented vertically, consistent with impacts on a precursor slope. Valleys converge down modern slopes, so the cratered dichotomy slope predates Late Noachian valley development. Degraded craters within the north-sloping cratered and dissected units have floors that are flat or slightly concave, so tilting did not occur after the crater floors were emplaced in Middle Noachian to Early Hesperian time. Most crater floors along the dichotomy boundary are not dissected, as one would expect from an erosional response to Late Noachian tilting, and the few craters with dissected floors have obvious outlet breaches and/or are interspersed with flat-floored craters along the steepest cratered slopes. Crater rim-lowering and infilling on the cratered slope often produced flat-floored amphitheaters that open to the north, which is a natural consequence of long-term erosion and infilling of craters that formed on slopes. Lithospheric extension has not disrupted fresh or degraded craters on north-sloping cratered terrain, which would occur if the convex slope formed at any time after the Early Noachian. The highlands and crustal dichotomy are isostatically compensated, whereas the younger Tharsis and Elysium regions are not, suggesting that the dichotomy formed during an earlier time of higher heat flow. Finally, the thin crust of the lowlands extends well beyond and therefore predates the Utopia basin, which formed in the Early Noachian as shown by its superimposed quasi-circular depressions (buried craters). These observations constrain the development of the lowland crust and therefore the crustal dichotomy to the Early Noachian, although a precise age is not yet available within this ~600 Ma epoch. Fretted terrain is confined within a superimposed Late Noachian plateau unit, which was extensively eroded during the Early Hesperian (~3.7-3.6 Ga), followed by lowland plains emplacement. Despite some erosion, the general form of the ancient dichotomy boundary is still preserved in cratered terrain, allowing geophysical models of crustal development to be tested. The transition zone and lowland terrains are >300 Ma younger and not relevant to the dichotomy origin.

  14. Communication as Social Relationship: Implications of the Cognitions-Behaviors Dichotomy for Communication Theory.

    ERIC Educational Resources Information Center

    Beach, Wayne A.; Fisher, B. Aubrey

    Communication researchers have typically specified either cognitions or behaviors as the crucial units of analysis. This cognitive/behavioral dichotomy is evident in current conceptualizations of social relationship as a summative combination of separate behaviors, or a joint product that goes beyond the constituent parts. Choosing cognitive or…

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

    ERIC Educational Resources Information Center

    Ippolito, John

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Burns, Edgar A. M.

    2012-01-01

    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…

  17. Dysfunctional Dichotomies? Deflating Bipolar Constructions of Curriculum and Pedagogy through Case Studies from Music and History

    ERIC Educational Resources Information Center

    Cain, Tim; Chapman, Arthur

    2014-01-01

    Recent public discussions of curriculum and pedagogy that have accompanied the English National Curriculum review have been structured around clichd dichotomies that generate more heat than light and that, as Robin Alexander has argued, reduce complex educational debates to oppositional and incompatible slogans. This paper begins by exploring the

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

    ERIC Educational Resources Information Center

    Tarvydas, Vilia; Addy, Amanda; Fleming, Allison

    2010-01-01

    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…

  19. Extreme(s) Makeover: Countering False Dichotomies of Literacy Education in the Australian Context

    ERIC Educational Resources Information Center

    Hamston, Julie; Scull, Janet

    2007-01-01

    This paper highlights some of the enduring dichotomies that prevail in Australia regarding the most effective way to teach literacy. These contrastive positions are often used by policymakers and the media to construct the view that teachers are failing to teach literacy well. In uncovering some of the polemical positions taken on literacy…

  20. Dysfunctional Dichotomies? Deflating Bipolar Constructions of Curriculum and Pedagogy through Case Studies from Music and History

    ERIC Educational Resources Information Center

    Cain, Tim; Chapman, Arthur

    2014-01-01

    Recent public discussions of curriculum and pedagogy that have accompanied the English National Curriculum review have been structured around clichéd dichotomies that generate more heat than light and that, as Robin Alexander has argued, reduce complex educational debates to oppositional and incompatible slogans. This paper begins by exploring the…

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

    ERIC Educational Resources Information Center

    Burns, Edgar A. M.

    2012-01-01

    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

  2. Moving beyond the Deep and Surface Dichotomy; Using Q Methodology to Explore Students' Approaches to Studying

    ERIC Educational Resources Information Center

    Godor, Brian P.

    2016-01-01

    Student learning approaches research has been built upon the notions of deep and surface learning. Despite its status as part of the educational research canon, the dichotomy of deep/surface has been critiqued as constraining the debate surrounding student learning. Additionally, issues of content validity have been expressed concerning…

  3. The Middle Way to Motivating Middle School Students by Avoiding False Dichotomies.

    ERIC Educational Resources Information Center

    Gehlbach, Hunter; Roeser, Robert W.

    2002-01-01

    Discusses motivation systems theory and the complexity of motivation. Recommends that teachers reframe traditional dual dichotomies concerning intrinsic versus extrinsic orientations in motivation, intellectual challenge versus self-esteem development, or personal growth versus shared standards by blending the best assets from both to create…

  4. Measuring Information Processing Speed in Mild Cognitive Impairment: Clinical Versus Research Dichotomy.

    PubMed

    Haworth, Judy; Phillips, Michelle; Newson, Margaret; Rogers, Peter J; Torrens-Burton, Anna; Tales, Andrea

    2016-01-22

    A substantial body of research evidence is indicative of disproportionately slowed information processing speed in a wide range of multi-trial, computer-based, neuroimaging- and electroencephalography-based reaction time (RT) tests in Alzheimer's disease and mild cognitive impairment (MCI). However, in what is arguably a dichotomy between research evidence and clinical practice, RT associated with different brain functions is rarely assessed as part of their diagnosis. Indeed, often only the time taken to perform a single, specific task, commonly the Trail making test (TMT), is measured. In clinical practice therefore, there can be a failure to assess adequately the integrity of the rapid, serial information processing and response, necessary for efficient, appropriate, and safe interaction with the environment. We examined whether a typical research-based RT task could at least match the TMT in differentiating amnestic MCI (aMCI) from cognitively healthy aging at group level. As aMCI is a heterogeneous group, typically containing only a proportion of individuals for whom aMCI represents the early stages of dementia, we examined the ability of each test to provide intra-group performance variation. The results indicate that as well as significant slowing in performance of the operations involved in TMT part B (but not part A), individuals with aMCI also experience significant slowing in RT compared to controls. The results also suggest that research-typical RT tests may be superior to the TMT in differentiating between cognitively healthy aging and aMCI at group level and in revealing the performance variability one would expect from an etiologically heterogeneous disorder such as aMCI. PMID:26836171

  5. The Crustal Dichotomy of Mars: Geological Testing and Constraints on Geophysical Models

    NASA Astrophysics Data System (ADS)

    Irwin, R. P.; Watters, T. R.

    2007-05-01

    The term `crustal dichotomy' refers to hemispheric scale differences in crustal thickness, surface age, elevation, and morphology between the southern cratered highlands and northern lowland plains of Mars. Empirical observations of the crustal dichotomy boundary provide important constraints on the timing and mechanisms of early crustal development, which remains poorly understood after 35 years of robotic exploration. Published models include endogenic (long-wavelength mantle convection, perhaps driving plate tectonics) and exogenic (one or more giant impacts) mechanisms. The dichotomy boundary consists of Early Noachian (~4.5 to 3.92 Ga) cratered slopes and a transition zone of Early Hesperian (~3.7 to 3.6 Ga) fretted and knobby terrains between the Noachian highland plateau and Hesperian lowland plains. The old cratered slope predates and influenced the morphometry of Hesperian and younger impact craters, the drainage planform of Late Noachian valley networks, and the erosional modification of Middle to Late Noachian (~3.92 to 3.7 Ga) impact craters. No extensional faults bisect Noachian fresh or degraded craters at higher elevations on the cratered slope, and crater floor deposits are flat rather than tilted, which indicate that the boundary and the lowlands formed very early in the Noachian Period. Formation of the dichotomy in the Early Noachian is consistent with the population of buried impact craters in the lowlands, SNC isotopic data, and the crustal magnetic field data. Late Noachian plateau materials, younger volcanic rocks of the Tharsis province, and Amazonian airfall materials of the Medusae Fossae Formation later buried the old cratered slope. Development of fretted and knobby terrains in the younger plateau materials appears to be structurally controlled, but we have identified no evidence for significant fault displacement. Tectonic and erosional features of these later terrains are not coeval with the crustal dichotomy and do not provide valid model constraints for Early Noachian processes. Many published models of the crustal dichotomy have one or more of the following issues: 1) long- lived processes that extend beyond the Early Noachian Epoch, 2) formation of complex fretted and knobby terrain using one-dimensional tensile stress, 3) use of Hesperian faults and landforms as model constraints, 4) limited applicability beyond the study area, and 5) insufficient testing to reject alternative endogenic hypotheses. Future modeling of the crustal dichotomy should focus on rapid endogenic mechanisms operating within the Early Noachian Epoch.

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

    NASA Astrophysics Data System (ADS)

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

    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.

  7. The great dichotomy of the Solar System: Small terrestrial embryos and massive giant planet cores

    NASA Astrophysics Data System (ADS)

    Morbidelli, A.; Lambrechts, M.; Jacobson, S.; Bitsch, B.

    2015-09-01

    The basic structure of the Solar System is set by the presence of low-mass terrestrial planets in its inner part and giant planets in its outer part. This is the result of the formation of a system of multiple embryos with approximately the mass of Mars in the inner disk and of a few multi-Earth-mass cores in the outer disk, within the lifetime of the gaseous component of the protoplanetary disk. What was the origin of this dichotomy in the mass distribution of embryos/cores? We show in this paper that the classic processes of runaway and oligarchic growth from a disk of planetesimals cannot explain this dichotomy, even if the original surface density of solids increased at the snowline. Instead, the accretion of drifting pebbles by embryos and cores can explain the dichotomy, provided that some assumptions hold true. We propose that the mass-flow of pebbles is two-times lower and the characteristic size of the pebbles is approximately ten times smaller within the snowline than beyond the snowline (respectively at heliocentric distance r rice , where rice is the snowline heliocentric distance), due to ice sublimation and the splitting of icy pebbles into a collection of chondrule-size silicate grains. In this case, objects of original sub-lunar mass would grow at drastically different rates in the two regions of the disk. Within the snowline these bodies would reach approximately the mass of Mars while beyond the snowline they would grow to ∼ 20 Earth masses. The results may change quantitatively with changes to the assumed parameters, but the establishment of a clear dichotomy in the mass distribution of protoplanets appears robust provided that there is enough turbulence in the disk to prevent the sedimentation of the silicate grains into a very thin layer.

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

    PubMed Central

    2007-01-01

    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

  9. Origin of the Martian global dichotomy by crustal thinning in the late Noachian or early Hesperian

    NASA Astrophysics Data System (ADS)

    McGill, George E.; Dimitriou, Andrew M.

    1990-08-01

    The marked dichotomy in topography, surface age, and crustal thickness between the northern lowland (NL) and southern upland of Mars has been explained as due to an initially inhomogeneous crust, a single megaimpact event, several overlapping large basin impacts, and first-order convective overtum of the Martian mantle. All of these hypotheses propose that the dichotomy was formed before the end of the primordial heavy bombardment. Geological data indicate episodes of fracturing and faulting in the late Noachian and the early Hesperian, within the NL and along the lowland/highland boundary. Igneous activity also peaked in the late Noachian and early Hesperian. These data suggest a tectonic event near the Noachian/Hesperian boundary characterized by enhanced heat loss and extensive fracturing, including formation of the faults that define much of the highland/lowland boundary. It is argued that the major result of this tectonic event was formation of the dichotomy by thinning of the crust above a large convection cell or plume.

  10. Maximum Power Point Tracking with Dichotomy and Gradient Method for Automobile Exhaust Thermoelectric Generators

    NASA Astrophysics Data System (ADS)

    Fang, W.; Quan, S. H.; Xie, C. J.; Tang, X. F.; Wang, L. L.; Huang, L.

    2016-03-01

    In this study, a direct-current/direct-current (DC/DC) converter with maximum power point tracking (MPPT) is developed to down-convert the high voltage DC output from a thermoelectric generator to the lower voltage required to charge batteries. To improve the tracking accuracy and speed of the converter, a novel MPPT control scheme characterized by an aggregated dichotomy and gradient (ADG) method is proposed. In the first stage, the dichotomy algorithm is used as a fast search method to find the approximate region of the maximum power point. The gradient method is then applied for rapid and accurate tracking of the maximum power point. To validate the proposed MPPT method, a test bench composed of an automobile exhaust thermoelectric generator was constructed for harvesting the automotive exhaust heat energy. Steady-state and transient tracking experiments under five different load conditions were carried out using a DC/DC converter with the proposed ADG and with three traditional methods. The experimental results show that the ADG method can track the maximum power within 140 ms with a 1.1% error rate when the engine operates at 3300 rpm@71 NM, which is superior to the performance of the single dichotomy method, the single gradient method and the perturbation and observation method from the viewpoint of improved tracking accuracy and speed.

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

    PubMed

    Sartenaer, Olivier

    2013-09-01

    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

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

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

    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,

  13. "A temporary oversimplification": Mayr, Simpson, Dobzhansky, and the origins of the typology/population dichotomy (part 2 of 2).

    PubMed

    Witteveen, Joeri

    2016-06-01

    The dichotomy between 'typological thinking' and 'population thinking' features in a range of debates in contemporary and historical biology. The origins of this dichotomy are often traced to Ernst Mayr, who is said to have coined it in the 1950s as a rhetorical device that could be used to shield the Modern Synthesis from attacks by the opponents of population biology. In this two-part essay, I argue that the origins of the typology/population dichotomy are considerably more complicated and more interesting than is commonly thought. In the first part, I argued that Mayr's dichotomy was based on two distinct type/population contrasts that had been articulated much earlier by George Gaylord Simpson and Theodosius Dobzhansky. Their distinctions made eminent sense in their own, isolated contexts. In this second part, I will show how Mayr conflated these type/population distinctions and blended in some of his own, unrelated concerns with 'types' of a rather different sort. Although Mayr told his early critics that he was merely making "a temporary oversimplification," he ended up burdening the history and philosophy of biology with a troubled dichotomy. PMID:26471926

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

    NASA Technical Reports Server (NTRS)

    Frey, Herbert V.

    2004-01-01

    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 and/or 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 northern hemisphere, which themselves can account for the lowland topography, suggest that large impacts played the major role in the origin Mars fundamental crustal feature.

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

    NASA Technical Reports Server (NTRS)

    Frey, H. V.

    2004-01-01

    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.

  16. Of natural bodies and antibodies: Parents' vaccine refusal and the dichotomies of natural and artificial.

    PubMed

    Reich, Jennifer A

    2016-05-01

    Despite eliminating incidences of many diseases in the United States, parents are increasingly rejecting vaccines for their children. This article examines the reasons parents offer for doing so. It argues that parents construct a dichotomy between the natural and the artificial, in which vaccines come to be seen as unnecessary, ineffective, and potentially dangerous. Using qualitative data from interviews and observations, this article shows first, how parents view their children's bodies, particularly from experiences of birth and with infants, as naturally perfect and in need of protection. Second, parents see vaccines as an artificial intervention that enters the body unnaturally, through injection. Third, parents perceive immunity occurring from illness to be natural and superior and immunity derived from vaccines as inferior and potentially dangerous. Finally, parents highlight the ways their own natural living serves to enhance their children's immunity rendering vaccines unnecessary. Taken together, this dichotomy allows parents to justify rejection of vaccines as a form of protecting children's health. These findings expose perceptions of science, technology, health, and the meanings of the body in ways that can inform public health efforts. PMID:27082021

  17. Channel slope reversal near the Martian dichotomy boundary: Testing tectonic hypotheses

    NASA Astrophysics Data System (ADS)

    Lefort, Alexandra; Burr, Devon M.; Nimmo, Francis; Jacobsen, Robert E.

    2015-07-01

    Faults along the Martian dichotomy boundary are evidence of tectonic activity, which by analogy with terrestrial tectonism may cause changes in or even reversal of fluvial longitudinal profiles. In the eastern hemisphere between 30° E and 150° E, this tectonic activity has been hypothesized to result from lower crustal flow or from lithospheric flexure, for which loading (e.g., by material deposition) of the northern lowlands is a possible cause (Watters, 2003a; Nimmo, 2005). The topographic (slope) changes resulting from these two different mechanisms are distinct and can provide a means for distinguishing between them, although other processes may complicate interpretations of reversed longitudinal profiles. Two fan-shaped networks of inverted channels are located near 150° E in the Aeolis Dorsa region just north of the dichotomy boundary. Their original flow directions, inferred from planform morphology, suggest flow to the northeast in contrast to their current longitudinal profiles sloping down to the southwest. This contrast indicates slope reversal. We investigate the lower crustal flow and flexure mechanisms for slope reversal by testing three different hypotheses: 1) lower crustal flow, 2) flexure caused by material erosion from the highlands and deposition in the lowlands, and 3) flexure caused by highland erosion and deposition in the lowlands plus deposition of the Medusae Fossae Formation in the lowlands. We test these three hypotheses by comparing the inferred magnitudes of the slope reversals with predicted slope changes from geophysical models for these processes. Taking the possibility of non-tectonic (i.e., collapse) processes into account, our results suggest that, among these three models, the slope reversal is most consistent with the predicted tectonic response to erosion and deposition of highland material in conjunction with deposition of the Medusae Fossae Formation. Contrary to previous findings, our results do not support the mechanism of lateral crustal flow, although they do not rule it out because lower crustal flow and erosion may both have been operating, but on different time scales. The result of this hypothesis-testing provides insight into the evolution of the dichotomy boundary and Martian crust in this location.

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

    ERIC Educational Resources Information Center

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

    2000-01-01

    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…

  19. Theory-Practice Dichotomy in Inquiry: Meanings and Preservice Teacher-Mentor Teacher Tension in Turkish Literacy Classrooms

    ERIC Educational Resources Information Center

    Yayli, Derya

    2008-01-01

    This study aims at exploring the meanings constructed by preservice teachers of literacy about theory-practice dichotomy and investigating the preservice teacher-mentor teacher tension during the internship period. Qualitative data were collected by preservice teachers as researchers in inquiry through field notes, reflective journals, observation…

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

    ERIC Educational Resources Information Center

    Sumida Huaman, Elizabeth; Valdiviezo, Laura Alicia

    2014-01-01

    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…

  1. How Can We Overcome the Dichotomy That Western Culture Has Created between the Concepts of Independence and Dependence?

    ERIC Educational Resources Information Center

    Gross, Zehavit

    2015-01-01

    The purpose of this article, inspired by the works of Martin Buber, is to propose an alternative to the inherent dichotomy of Western culture. It may allow Western culture to transcend its fixed nature towards new directions and to suggest challenging solutions for reshaping the questions--what is the role of man in the world, and what is the…

  2. How Can We Overcome the Dichotomy That Western Culture Has Created between the Concepts of Independence and Dependence?

    ERIC Educational Resources Information Center

    Gross, Zehavit

    2015-01-01

    The purpose of this article, inspired by the works of Martin Buber, is to propose an alternative to the inherent dichotomy of Western culture. It may allow Western culture to transcend its fixed nature towards new directions and to suggest challenging solutions for reshaping the questions--what is the role of man in the world, and what is the

  3. Large impact basins and the mega-impact origin for the crustal dichotomy on Mars

    NASA Technical Reports Server (NTRS)

    Frey, Herbert; Schultz, Richard A.

    1988-01-01

    The hypothesis that the crustal dichotomy on Mars is due to a single giant (mega) impact early in Martian history is tested by determining the number of 'missing' basins, the difference between the observed number of large impact basins on Mars and the number expected from a 1/D-squared distribution. If the Borealis Basin was the largest member of a 1/D-squared impact population, a large number of 'missing' basins is expected which is too large to be hidden by the younger surface units. If Chryse is the largest member of a 1/D-squared impact population, the more modest number of 'missing' basins could be confined to areas of Mars that have been resurfaced or reworked by subsequent geologic processes.

  4. Multiple populations in globular clusters and the origin of the Oosterhoff dichotomy

    NASA Astrophysics Data System (ADS)

    Jang, S.; Lee, Y.-W.

    2016-05-01

    The globular cluster community is now facing a new paradigm of multiple stellar populations. In light of this, we have recently proposed a new model to explain the origin of the difference in mean period of type ab RR Lyrae variables between the two Oosterhoff groups. In our model, the instability strip in the metal-poor group II clusters, such as M15, is populated by second-generation stars (G2) with mildly enhanced helium and CNO abundances, while the RR Lyraes in the relatively metal-rich group I clusters such as M3 are produced mostly by first-generation stars (G1) without these enhancements. When these models are extended to all metallicity regimes, the observed dichotomies in the inner and outer halo globular clusters can be naturally reproduced. We found that specific star formation histories are required for the inner and outer halos, which is consistent with the dual origin of the Milky Way halo.

  5. Chaotic motion of Europa and Ganymede and the Ganymede-Callisto dichotomy

    NASA Technical Reports Server (NTRS)

    Tittemore, William C.

    1990-01-01

    Europa and Ganymede may have undergone an episode of chaotic motion before the establishment of the current Laplace resonance involving the three inner GAlilean satellites. During this episode, the orbital eccentricities of both satellites may have increased dramatically. As a result, the mechanical stresses due to tidal deformation of the satellites' icy lithospheres may have been large enough to result in extensive fracturing, and tidal heating may have melted water ice in the mantles of both satellites, triggering the geological activity that has modified their surfaces since the heavy cratering period. The tidal effects on Ganymede during this episode provide an explanation of the dichotomy between it and Callisto, which have similar bulk properties but very different geological histories.

  6. The Crustal Dichotomy Boundary West of Tempe Terra: Speculation on Where it Lies Beneath Alba Patera Based on Mola Topography

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    MOLA gridded data based on profiles collected during the Aerobraking Hiatus and Science Phasing Operations suggest the crustal dichotomy boundary west of Tempe continues beneath Alba volcanics, at least to 105 W at about 50 N. A broad shelf-like region in the Alba units is continuous with a similar region of Tempe in which Hesperian volcanics overlie Noachian cratered terrain. Perspective views show significant changes in the sloping character of the flanks of Alba east and west of 105W, with much more continuous steep topography to the west. We suggest that Alba sits astride the ancient crustal dichotomy boundary, not adjacent to it, and that its eastern half lies on old cratered terrain. If true, this would significantly affect the estimate of Alba volcanics volumes, and might also explain some of the observed asymmetries in the structure and the distribution of faults associated with this immense feature.

  7. Origin of the great dichotomy of the Solar System: small terrestrial embryos and massive giant planet cores

    NASA Astrophysics Data System (ADS)

    Morbidelli, Alessandro; Lambrechts, Michiel; Bitsch, Bertram; Jacobson, Seth

    2015-08-01

    The basic structure of the solar system is set by the presence of low-mass terrestrial planets in its inner part and giant planets in its outer part. This is the result of the formation of a system of multiple Mars-mass embryos in the inner disk and of a few multi-Earth-mass cores in the outer part, within the lifetime of the gaseous component of the protoplanetary disk. What was the origin of this dichotomy in the mass distribution of embryos/cores? We show in this paper that the classic processes of runaway and oligarchic growth from a disk of planetesimals can not explain this dichotomy, even if the original surface density of solids increased at the snowline. Instead, the accretion of drifting pebbles by embryos/cores can explain the dichotomy, provided that some assumptions hold true. We propose that the mass flow of pebbles is two-times lower and the characteristic size of the pebbles is ten times smaller within the snowline than beyond the snowline (respectively at r < r_ice and r > r_ice, where r_ice is the snowline heliocentric distance), due to ice sublimation and the splitting of icy pebbles into a collection of chondrule-size silicate grains. In this case, objects of original sub-lunar mass would grow at drastically different rates in the two regions of the disk. Within the snowline these bodies would reach approximately the mass of Mars while beyond the snowline they would grow to 20 Earth masses. The results may change quantitatively with the assumed parameters, but the establishment of a clear dichotomy in the mass distribution of protoplanets appears robust.

  8. A validated FISH trisomy index demonstrates the hyperdiploid and nonhyperdiploid dichotomy in MGUS.

    PubMed

    Chng, Wee Joo; Van Wier, Scott A; Ahmann, Gregory J; Winkler, Jerry M; Jalal, Syed M; Bergsagel, Peter Leif; Chesi, Marta; Trendle, Mike C; Oken, Martin M; Blood, Emily; Henderson, Kim; Santana-Dvila, Rafael; Kyle, Robert A; Gertz, Morie A; Lacy, Martha Q; Dispenzieri, Angela; Greipp, Philip R; Fonseca, Rafael

    2005-09-15

    Two major genetic categories of multiple myeloma (MM) exist. Hyperdiploid MM (48 to 74 chromosomes, median 53 chromosomes) is associated with trisomies especially of chromosomes 3, 7, 9, 11, 15, and 19, whereas the nonhyperdiploid (< 48 chromosomes or more than 74 chromosomes) MM is associated with primary translocations such as t(11;14), t(4;14), and t(14;16). Whether this dichotomy exists in monoclonal gammopathy of undetermined significance (MGUS) is uncertain due to limitations of current methods in the study of ploidy. This is especially true in MGUS where the number of clonal plasma cells is small. In this study, we derived a fluorescent in situ hybridization (FISH)-based trisomy index from pooled cytogenetic data (karyotype analysis) from 2 large cohorts of patients with MM with abnormal karyotype, and then validated it in 2 independent cohorts of patients who had known ploidy status either by karyotyping or DNA content measurement using flow cytometry. Using the criteria of 2 or more trisomies from a 3-chromosome combination, hyperdiploid myeloma can be detected with high specificity. Applying this index on 28 patients with smoldering multiple myeloma (SMM) or MGUS (11 SMM, 17 MGUS) who had normal karyotype, 11 cases of hyperdiploid SMM/MGUS were detected. This percentage (40%) is remarkably similar to the percentage of hyperdiploid MM reported in the literature, suggesting that hyperdiploid MM may originate early during disease evolution. PMID:15920009

  9. Universal tectonic dichotomy of small celestial bodies expressed in their common convexo-concave shapes

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2008-09-01

    The wave planetology [1, 2, 3 & others] declares in its first theorem that all celestial bodies are dichotomous. This is a result of a warping action of the fundamental wave (wave 1 long 2πR where R is a body radius) that appears in any body due to its movement in non-round (elliptical, parabolic) keplerian orbits with periodically changing accelerations. Having a standing character and four crossing directions in rotating bodies (but all bodies rotate!) these waves inevitably press in one hemisphere and bulge out the opposite one tending to impose on a body convexo-concave shape. This shape is leveled out in larger bodies due to enhanced gravity but is clearly observed in smaller ones with diminished gravity. Still, in the larger bodies as, for an example, in Earth the tectonic dichotomy is expressed as an opposition of the subsided western Pacific hemisphere and the uplifted eastern continental hemisphere. At Mars even sharper dichotomy is in the north-south direction. Small bodies (normally less than 400-500 km across) notwithstanding their type (asteroids, comets, satellites), size and composition (stones, metals, ices) are flattened and bended by the fundamental wave. That is why all asteroids in the main asteroid belt have an oblong shape what was established rather long ago but never was properly explained. Now a number of small satellites is observed by Cassini spacecraft in the saturnian system that makes together with jovian and martian small satellites a representative group for comparisons. In the figures below are shown asteroids, satellites and a comet arranged in a row of increasing sizes. They all are flattened except the largest in the row Enceladus (505 km) and bended tending to acquire a convexo-concave shape. Asteroids: Itokawa (0.5 km long), Eros (33 km, PIA03111). Satellites: Calypso (22 km, PIA07633), Atlas (32 km, PIA08233), Prometheus (102 km, PIA08192), Hyperion (350 km, PIA06645), Enceladus (505 km, PIA08258, comet-like behaviour). Comet: Borrelli (core 8 km long). Various body types, sizes, compositions, but there is the same style of deformation because of a warping action of the fundamental wave long 2πR. There is a tendency to extend and break the convex hemisphere with production of deep cracks ("saddles") and to squeeze (contract) an antipodean one expelling internal material (a scheme of this process is in the drawing -the upper right corner). In extreme cases a body can break down with production of binaries and satellites of small bodies what is not rare in cosmos. A satellite Calypso and an asteroid Eros have near sizes but different compositions (ice and stone) and occur in different zones of the solar system. But they are deformed similarly. A bending action leaves morphological traces on body surfaces. In this respect the 102 km long satellite Prometheus is very exemplary as it shows diverging ridges with closer spaced ends at the concave hemisphere (up in the image) and wider spaced ends at the convex one. This pattern witnesses an opposition of contracted and extended hemispheres. In volatile rich bodies - comets this process is marked by squeezing material under contraction from the concave hemisphere (dust-gaseous tale) and more quite degassing of cracked convex hemisphere (Borrelli). This dichotomy shows also icy satellite Enceladus. Its southern pole region under contraction (the tiger stripes structure) expels vapor-ice mixture; its northern pole region in contrast is quite but has many craters - traces of the past degassing. In this respect the tiny icy satellite could be treated as a large comet core still spitting material into space; this material is not wasted vainly but is needed to mighty Saturn for making one of its outer rings (E-ring). The largest irregular satellite in the solar system - Hyperion has various appearances in many acquired images. It is not so oblong as smaller bodies but its convexo-concave shape is very pronounced. Its polygonal outlines also can be seen betraying a tendency to acquire a tetrahedron shape. The simplest Plato's figure - tetrahedron is dichotomous in its nature because a section across any of its four axes produces from one side a vertex and from another a face. To a vertex three faces narrow - contraction, to a face three other faces diverge - extension. So, dichotomous structures of celestial bodies are an expression of their wave geometrization by interfering fundamental waves. In figures from the right row the tetrahedron features of satellites are seen more sharply: Hyperion- PIA08904, dimension 175 x 120 x 100 km, Thebe-PIA02531, 110 km, Telesto-PIA07546, 25 km across. References: 1. Kochemasov G.G. Concerted wave supergranulation of the solar system bodies // 16th Russian-American microsymposium on planetology, Abstracts, Moscow, Vernadsky Inst. (GEOKHI), 1992, 36-37. 2. Kochemasov G.G. Tectonic dichotomy, sectoring and granulation of Earth and other celestial bodies // Proceedings of the International Symposium on New Concepts in Global Tectonics, "NCGT-98 TSUKUBA", Geological Survey of Japan, Tsukuba, Nov 20-23, 1998, p. 144-147. 3. Kochemasov G.G. Theorems of wave planetary tectonics // Geophys. Res. Abstr.1999. V.1, #3, p.700.

  10. The dichotomy between strong and ultra-weak magnetic fields among intermediate-mass stars

    NASA Astrophysics Data System (ADS)

    Lignières, François; Petit, Pascal; Aurière, Michel; Wade, Gregg A.; Böhm, Torsten

    2014-08-01

    Until recently, the detection of magnetic fields at the surface of intermediate-mass main-sequence stars has been limited to Ap/Bp stars, a class of chemically peculiar stars. This class represents no more than 5-10% of the stars in this mass range. This small fraction is not explained by the fossil field paradigm that describes the Ap/Bp type magnetism as a remnant of an early phase of the star-life. Also, the limitation of the field measurements to a small and special group of stars is obviously a problem to study the effect of the magnetic fields on the stellar evolution of a typical intermediate-mass star. Thanks to the improved sensitivity of a new generation of spectropolarimeters, a lower bound to the magnetic fields of Ap/Bp stars, a two orders of magnitude desert in the longitudinal magnetic field and a new type of sub-gauss magnetism first discovered on Vega have been identified. These advances provide new clues to understand the origin of intermediate-mass magnetism as well as its influence on stellar evolution. In particular, a scenario has been proposed whereby the magnetic dichotomy between Ap/Bp and Vega-like magnetism originate from the bifurcation between stable and unstable large scale magnetic configurations in differentially rotating stars. In this paper, we review these recent observational findings and discuss this scenario.

  11. Does black hole spin play a key role in the FSRQ/BL Lac dichotomy?

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Debbijoy; Sreekumar, Parameswaran; Mukhopadhyay, Banibrata; Tomar, Ishan

    2016-04-01

    Blazars are characterized by large intensity and spectral variations across the electromagnetic spectrum It is believed that jets emerging from them are almost aligned with the line-of-sight. The majority of identified extragalactic sources in γ-ray catalogs of EGRET and Fermi are blazars. Observationally, blazars can be divided into two classes: flat spectrum radio quasars (FSRQs) and BL Lacs. BL Lacs usually exhibit lower γ-ray luminosity and harder power law spectra at γ-ray energies than FSRQs. We attempt to explain the high energy properties of FSRQs and BL Lacs from Fermi γ-ray space telescope observations. It was argued previously that the difference in accretion rates is mainly responsible for the large mismatch in observed luminosity in γ-ray. However, when intrinsic luminosities are derived by correcting for beaming effects, this difference in γ-ray luminosity between the two classes is significantly reduced. In order to explain this difference in intrinsic luminosities, we propose that spin plays an important role in the luminosity distribution dichotomy of BL Lacs and FSRQs. As the outflow power of a blazar increases with increasing spin of a central black hole, we suggest that the spin plays a crucial role in making BL Lac sources low luminous and slow rotators compared to FSRQ sources.

  12. High-performance modeling acoustic and elastic waves using the parallel Dichotomy Algorithm

    NASA Astrophysics Data System (ADS)

    Fatyanov, Alexey G.; Terekhov, Andrew V.

    2011-03-01

    A high-performance parallel algorithm is proposed for modeling the propagation of acoustic and elastic waves in inhomogeneous media. An initial boundary-value problem is replaced by a series of boundary-value problems for a constant elliptic operator and different right-hand sides via the integral Laguerre transform. It is proposed to solve difference equations by the conjugate gradient method for acoustic equations and by the GMRES( k) method for modeling elastic waves. A preconditioning operator was the Laplace operator that is inverted using the variable separation method. The novelty of the proposed algorithm is using the Dichotomy Algorithm [26], which was designed for solving a series of tridiagonal systems of linear equations, in the context of the preconditioning operator inversion. Via considering analytical solutions, it is shown that modeling wave processes for long instants of time requires high-resolution meshes. The proposed parallel fine-mesh algorithm enabled to solve real application seismic problems in acceptable time and with high accuracy. By solving model problems, it is demonstrated that the considered parallel algorithm possesses high performance and efficiency over a wide range of the number of processors (from 2 to 8192).

  13. Dichotomy of rhinoplasty practice: from the conference floor to the operating room.

    PubMed

    Palma, Pietro; Khodaei, Iman

    2014-04-01

    Advancements in surgical techniques and improvements in clinical practice inevitably lag behind scientific progress and peer-led opinion. The rapid rise and fall in the popularity of rhinoplasty techniques makes scientific evidence-gathering and education a daunting task. Students of rhinoplasty face a long and steep learning curve, and need to acquire sound analytical tools to critically evaluate both literature contributions and operative reports shown in conferences. Such a complex learning process requires continuous self-examination, and must account for the increasingly sophisticated and intricate wishes of rhinoplasty patients whose desires do not always coincide with what surgeons have been taught and practiced. In contemporary practice, the developing rhinoplasty surgeon must be also familiar with the range of racial features, as the broad variety of nasal anatomies and beauty canons are truly staggering, and one formula does not fit all cases.The complex set of circumstances that lead to disharmony between scientific progress and clinical practice is addressed, and a utilitarian plan to remedy this awkward dichotomy is suggested. PMID:24810121

  14. Dichotomy of decorin activity on the insulin-like growth factor-I system

    PubMed Central

    Morrione, Andrea; Neill, Thomas; Iozzo, Renato V.

    2013-01-01

    The stromal-specific proteoglycan decorin has emerged in recent years as a critical regulator of tumor initiation and progression. Decorin regulates the biology of various types of cancer by modulating the activity of several tyrosine-kinase receptors coordinating growth, survival, migration, and angiogenesis. Decorin binds to surface receptors for the epidermal and hepatocyte growth factors (EGF and HGF) with high affinity and negatively regulates their activity and signaling via robust internalization and eventual degradation. The insulin-like growth factor I (IGF-I) system plays a critical role in the regulation of cell growth both in vivo and in vitro. The IGF-I receptor (IGF-IR) is also essential for cellular transformation due to its ability to enhance cell proliferation and protect cancer cells from apoptosis. Recent data have pointed out a role of decorin in regulating the IGF-I system in both non-transformed and transformed cells. Significantly, there is a surprising dichotomy in the mechanisms of decorin action on IGF-IR signaling, which considerably differs between physiological and pathological cellular models. In this review, we summarize the current knowledge on decorin regulation of the IGF-I system in normal and transformed cells, and discuss possible decorin-based therapeutic approaches to target IGF-IR-driven tumors. PMID:23351020

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

    SciTech Connect

    Li Shulin; Agnor, C.B.; Lin, D. N. C.

    2010-09-10

    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.

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

    SciTech Connect

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

    2012-04-15

    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.

  17. Mutational dichotomy in desmoplastic malignant melanoma corroborated by multigene panel analysis.

    PubMed

    Jahn, Stephan W; Kashofer, Karl; Halbwedl, Iris; Winter, Gerlinde; El-Shabrawi-Caelen, Laila; Mentzel, Thomas; Hoefler, Gerald; Liegl-Atzwanger, Bernadette

    2015-07-01

    Desmoplastic malignant melanoma is a distinct melanoma entity histologically subtyped into mixed and pure forms due to significantly reduced lymph node metastases in the pure form. Recent reports investigating common actionable driver mutations have demonstrated a lack of BRAF, NRAS, and KIT mutation in pure desmoplastic melanoma. In search for alternative driver mutations next generation amplicon sequencing for hotspot mutations in 50 genes cardinal to tumorigenesis was performed and in addition the RET G691S polymorphism was investigated. Data from 21 desmoplastic melanomas (12 pure and 9 mixed) were retrieved. Pure desmoplastic melanomas were either devoid of mutations (50%) or displayed mutations in tumor suppressor genes (TP53, CDKN2A, and SMAD4) singularly or in combination with the exception of a PIK3CA double-mutation lacking established biological relevance. Mixed desmoplastic melanomas on the contrary were frequently mutated (89%), and 67% exhibited activating mutations similar to common-type cutaneous malignant melanomas (BRAF, NRAS, FGFR2, and ERBB2). Separate analysis of morphologically heterogeneous tumor areas in four mixed desmoplastic malignant melanomas displayed no difference in mutation status and RET G691 status. GNAQ and GNA11, two oncogenes in BRAF and NRAS wild-type uveal melanomas, were not mutated in our cohort. The RET G691S polymorphism was found in 25% of pure and 38% of mixed desmoplastic melanomas. Apart from RET G691S our findings demonstrate absence of activating driver mutations in pure desmoplastic melanoma beyond previously investigated oncogenes (BRAF, NRAS, and KIT). The findings underline the therapeutic dichotomy of mixed versus pure desmoplastic melanoma with regard to activating mutations primarily of the mitogen-activated protein kinase pathway. PMID:25769001

  18. Novel Insights on Hantavirus Evolution: The Dichotomy in Evolutionary Pressures Acting on Different Hantavirus Segments

    PubMed Central

    Sankar, Sathish; Upadhyay, Mohita; Ramamurthy, Mageshbabu; Vadivel, Kumaran; Sagadevan, Kalaiselvan; Nandagopal, Balaji; Vivekanandan, Perumal; Sridharan, Gopalan

    2015-01-01

    Background Hantaviruses are important emerging zoonotic pathogens. The current understanding of hantavirus evolution is complicated by the lack of consensus on co-divergence of hantaviruses with their animal hosts. In addition, hantaviruses have long-term associations with their reservoir hosts. Analyzing the relative abundance of dinucleotides may shed new light on hantavirus evolution. We studied the relative abundance of dinucleotides and the evolutionary pressures shaping different hantavirus segments. Methods A total of 118 sequences were analyzed; this includes 51 sequences of the S segment, 43 sequences of the M segment and 23 sequences of the L segment. The relative abundance of dinucleotides, effective codon number (ENC), codon usage biases were analyzed. Standard methods were used to investigate the relative roles of mutational pressure and translational selection on the three hantavirus segments. Results All three segments of hantaviruses are CpG depleted. Mutational pressure is the predominant evolutionary force leading to CpG depletion among hantaviruses. Interestingly, the S segment of hantaviruses is GpU depleted and in contrast to CpG depletion, the depletion of GpU dinucleotides from the S segment is driven by translational selection. Our findings also suggest that mutational pressure is the primary evolutionary pressure acting on the S and the M segments of hantaviruses. While translational selection plays a key role in shaping the evolution of the L segment. Our findings highlight how different evolutionary pressures may contribute disproportionally to the evolution of the three hantavirus segments. These findings provide new insights on the current understanding of hantavirus evolution. Conclusions There is a dichotomy among evolutionary pressures shaping a) the relative abundance of different dinucleotides in hantavirus genomes b) the evolution of the three hantavirus segments. PMID:26193652

  19. Enceladus: opposition of expanded north and compacted south - an impressive example of tectonic dichotomy

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2011-10-01

    Ubiquitous tectonic dichotomy characteristic of all celestial bodies (Theorem 1 [1-3 & others]) has a very original face in the Enceladus' case. This rich in ice body continues to outgas and in this sense could be compared with comets. Spectacular outgassing continues only from the southern strongly squeezed terrains and does not show itself at the north where only numerous craters (partially impacts) reveal rather intensive outgassing in the past. The double nature of celestial bodies (expansion and compression) is due to their movements in keplerian non - circular orbits with periodically changing accelerations causing inertia-gravity waves warping bodies. These warpings in rotating bodies (but all bodies rotate!) have interfering ortho- and diagonal directions, standing character and harmonic wavelengths. The fundamental wave 1 long 2π R and the most intensive inevitably bulges out (e xpands) one hemisphere-segment and presses in (compacts) the opposite one. In the larger bodies like Earth keeping their spherical shape due to an important gravity there are the uplifted hemisphere and th e subsided one. At Earth, for an example, the continental eastern hemisphere and the opposite Pacific western one. The smaller bodies like asteroids, comet cores and many satellites do not have sufficient gravity to withstand the warping wave force and th us acquire oblong convexo-concave shape of a bean or banana [4]. A transition between "smaller" and "larger" bodies lies often somewhere in between 400 to 500 km in diameter. Thus, Enceladus is at the limit of this interval. It is spherical but shows a clear difference between two hemispheres (North against South like at Mars). The outgassing scrambled south remind the recently acquired images of the Hartley 2 comet (EPOXI mission) where dust -gas jets "spit out" of intensively compact layered in a few directions areas [5]. Temperature dichotomous Mimas also resembles Enceladus in what concerns hemispheric distribution of heat.

  20. Cyclin-dependent kinase 5 activates guanine nucleotide exchange factor GIV/Girdin to orchestrate migration–proliferation dichotomy

    PubMed Central

    Bhandari, Deepali; Lopez-Sanchez, Inmaculada; To, Andrew; Lo, I-Chung; Aznar, Nicolas; Leyme, Anthony; Gupta, Vijay; Niesman, Ingrid; Maddox, Adam L.; Garcia-Marcos, Mikel; Farquhar, Marilyn G.; Ghosh, Pradipta

    2015-01-01

    Signals propagated by receptor tyrosine kinases (RTKs) can drive cell migration and proliferation, two cellular processes that do not occur simultaneously—a phenomenon called “migration–proliferation dichotomy.” We previously showed that epidermal growth factor (EGF) signaling is skewed to favor migration over proliferation via noncanonical transactivation of Gαi proteins by the guanine exchange factor (GEF) GIV. However, what turns on GIV-GEF downstream of growth factor RTKs remained unknown. Here we reveal the molecular mechanism by which phosphorylation of GIV by cyclin-dependent kinase 5 (CDK5) triggers GIV's ability to bind and activate Gαi in response to growth factors and modulate downstream signals to establish a dichotomy between migration and proliferation. We show that CDK5 binds and phosphorylates GIV at Ser1674 near its GEF motif. When Ser1674 is phosphorylated, GIV activates Gαi and enhances promigratory Akt signals. Phosphorylated GIV also binds Gαs and enhances endosomal maturation, which shortens the transit time of EGFR through early endosomes, thereby limiting mitogenic MAPK signals. Consequently, this phosphoevent triggers cells to preferentially migrate during wound healing and transmigration of cancer cells. When Ser1674 cannot be phosphorylated, GIV cannot bind either Gαi or Gαs, Akt signaling is suppressed, mitogenic signals are enhanced due to delayed transit time of EGFR through early endosomes, and cells preferentially proliferate. These results illuminate how GIV-GEF is turned on upon receptor activation, adds GIV to the repertoire of CDK5 substrates, and defines a mechanism by which this unusual CDK orchestrates migration–proliferation dichotomy during cancer invasion, wound healing, and development. PMID:26286990

  1. Three-dimensional Relativistic MHD Simulations of Active Galactic Nuclei Jets: Magnetic Kink Instability and Fanaroff-Riley Dichotomy

    NASA Astrophysics Data System (ADS)

    Tchekhovskoy, Alexander; Bromberg, Omer

    2016-04-01

    Energy deposition by active galactic nuclei jets into the ambient medium can affect galaxy formation and evolution, the cooling of gas flows at the centres of galaxy clusters, and the growth of the supermassive black holes. However, the processes that couple jet power to the ambient medium and determine jet morphology are poorly understood. For instance, there is no agreement on the cause of the well-known Fanaroff-Riley (FR) morphological dichotomy of jets, with FRI jets being shorter and less stable than FRII jets. We carry out global 3D magnetohydrodynamic simulations of relativistic jets propagating through the ambient medium. We show that the flat density profiles of galactic cores slow down and collimate the jets, making them susceptible to the 3D magnetic kink instability. We obtain a critical power, which depends on the galaxy core mass and radius, below which jets become kink-unstable within the core, stall, and inflate cavities filled with relativistically-hot plasma. Jets above the critical power stably escape the galaxy cores and form powerful backflows. Thus, the kink instability controls the jet morphology and can lead to the FR dichotomy. The model-predicted dependence of the critical power on the galaxy optical luminosity agrees well with observations.

  2. Water in the Lunar Interior and the Apparent KREEP-Mare Dichotomy

    NASA Astrophysics Data System (ADS)

    McCubbin, F. M.; Nekvasil, H.

    2010-12-01

    Recent SIMS analysis of lunar apatite has shown that hydroxyl is structurally bound within lunar apatite from a number of different lunar lithologic types (McCubbin et al., 2010a, 2010b; Boyce et al., 2010; Greenwood et al., 2010). These studies along with previous SIMS analyses of lunar fire fountain glasses (Saal et al., 2008) confirm that there is at least some water in the lunar interior, with abundance estimates in magmatic source regions ranging from 64 ppb to 5 ppm water (McCubbin et al., 2010a). Surprisingly, apatite from rocks with KREEP-rich incompatible trace element signatures are depleted in hydroxyl in comparison to apatite from typical mare basalts. This result is counter-intuitive to the lunar magma ocean model, which predicts that incompatible constituents (e.g., water) would have been concentrated in the last dregs of liquid referred to as “urKREEP”. The mare basalts, which formed by partial melting of earlier LMO cumulates, are typically depleted in these incompatible constituents. Complicating the issue further, chlorine, another incompatible magmatic volatile element in apatite, follows the predicted trend with apatite from KREEP-rich rocks containing significant chlorine concentrations in comparison to apatite from mare basalts (McCubbin et al., 2009). The preceding results imply one of two scenarios 1) Water did not behave incompatibly during LMO crystallization and was preferentially stored within the LMO cumulate minerals 2) A secondary process such as degassing has perturbed the initial volatile contents of the urKREEP liquid or of the secondary magmas that have KREEP-rich incompatible trace element signatures. In regards to the first scenario, the mineral melt partition coefficients for water would need to have exceeded unity at the very low water concentrations of the LMO liquid. This scenario is consistent with the behavior of chlorine, as chlorine is not typically stored in nominally anhydrous phases like pyroxene or olivine, likely due to its large ionic radius. However, there is no empirical or experimental evidence to support the elevated D values for water. Regarding the second scenario, if significant degassing of the urKREEP liquid or KREEP-rich secondary magmas occurred, water would have certainly been lost preferentially to the other volatile constituents in apatite (fluorine and chlorine); however chlorine isotopes analyzed in lunar apatites are highly fractionated (Sharp et al., 2010), indicating degassing of chlorine in the absence of water. Therefore, this scenario only works if degassing on the Moon was a multi-stage and complex process where water and chlorine degassing are decoupled, which is not typically the case for terrestrial systems (Aiuppa et al., 2009, Webster and De Vivo, 2002; Webster et al., 1999). Solving this apparent KREEP-mare dichotomy regarding magmatic volatiles in the lunar interior is the next important step in figuring out the importance, relevance, and implications of water in the lunar interior. Moreover, it will lend insight into the roles of the other magmatic volatiles during the thermal and magmatic evolution of the Moon.

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

    SciTech Connect

    Balokovic, M.; Smolcic, V.; Ivezic, Z.; Zamorani, G.; Schinnerer, E.; Kelly, B. C.

    2012-11-01

    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.

  4. 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)

    Baloković, M.; Smolčić, V.; Ivezić, Ž.; Zamorani, G.; Schinnerer, E.; Kelly, B. C.

    2012-11-01

    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.

  5. Is there an association between postural balance and pulmonary function in adults with asthma?

    PubMed Central

    de Almeida, Vívian Pinto; Guimarães, Fernando Silva; Moço, Vanessa Joaquim Ribeiro; de Sá Ferreira, Arthur; de Menezes, Sara Lucia Silveira; Lopes, Agnaldo José

    2013-01-01

    OBJECTIVE: Asthma may cause systemic repercussions due to its severity and the effects of treatment. Our objective was to compare posture, balance, functional capacity, and quality of life (QOL) according to the severity of disease, as assessed by pulmonary function levels. METHOD: This cross-sectional study evaluated fifty individuals with asthma. We compared two groups of adult individuals who were divided according to the median of the forced expiratory volume in one second (FEV1) as follows: group A  =  FEV1>74% predicted; group B  =  FEV1<74% predicted. All patients underwent the following tests: spirometry, whole-body plethysmography, diffusing capacity for carbon monoxide (DLco), respiratory muscle strength, posture assessment, stabilometry, six-minute walking distance (6MWD), and QOL. RESULTS: All pulmonary function variables exhibited statistically significant differences between the two groups, except for the DLco. The maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and 6MWD were lower in group B. The maximal mediolateral velocity and the mediolateral displacement were significantly different, while the postural changes and QOL were similar between the groups. CONCLUSIONS: In adult individuals with asthma, the pulmonary function is associated with balance control in the mediolateral direction but does not influence the postural changes or QOL. PMID:24270954

  6. 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

    Zhang, Huajun

    2013-01-01

    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

  7. 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

    Zhang, Huajun

    2013-01-01

    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…

  8. The "enduring mission" of Zing-Yang Kuo to eliminate the nature-nurture dichotomy in psychology.

    PubMed

    Honeycutt, Hunter

    2011-05-01

    This paper reviews the arguments against the instinct concept and the nature-nurture dichotomy put forward by Zing-Yang Kuo (1898-1970) during the 1920s. Kuo insisted that nativism represented a kind of finished psychology, and that the labels of nature and nurture reflected and promoted one's ignorance of the development of a trait. Also discussed are his lesser known lines of research on the origins of the so-called rat-killing instinct in cats and his analysis on the determinants of animal fighting. His research illustrated the shortcomings of a nature-nurture framework and highlighted the necessity of his developmentally grounded alternative to studying behavior. Reasons for why Kuo's work has been marginalized in modern histories of psychology are also discussed. PMID:21305541

  9. Toward Understanding the Fanaroff-Riley Dichotomy in Radio Source Morphology and Power

    NASA Astrophysics Data System (ADS)

    Baum, Stefi A.; Zirbel, Esther L.; O'Dea, Christopher P.

    1995-09-01

    In Paper I we presented the results of a study of the interrelationships between host galaxy magnitude, optical line luminosity, and radio luminosity in a large sample of Fanaroff-Riley classes 1 and 2 (FR 1 and FR 2) radio galaxies. We report several important differences between the FR 1 and FR 2 radio galaxies. At the same host galaxy magnitude or radio luminosity, the FR 2's produce substantially more optical line emission (by roughly an order of magnitude or more) than do FR 1's. Similarly, FR 2 sources produce orders of magnitude more line luminosity than do radio-quiet galaxies of the same optical magnitude, while FR 1 sources and radio-quiet galaxies of the same optical magnitude produce similar line luminosities. Combining these results with previous results from the literature, we conclude that while the emission-line gas in the FR 2's is indeed photoionized by a nuclear UV continuum source from the AGN, the emission-line gas in the FR 1's may be energized predominantly by processes associated with the host galaxy itself. The apparent lack of a strong UV continuum source from the central engine in FR 1 sources can be understood in two different ways. In the first scenario, FR l's are much more efficient at covering jet bulk kinetic energy into radio luminosity than FR 2's, such that an FR 1 has a much lower bolometric AGN luminosity (hence nuclear UV continuum source) than does an FR 2 of the same radio luminosity. We discuss the pros and cons of this model and conclude that the efficiency differences needed between FR 2 and FR 1 radio galaxies are quite large and may lead to difficulties with the interpretation since it would suggest that FR 2 radio source deposit very large amounts of kinetic energy into the ISM Intracluster Medium. However, this interpretation remains viable. Alternatively, it may be that the AGNs in FR 1 sources simply produce far less radiant UV energy than do those in FR 2 sources. That is, FR 1 sources may funnel a higher fraction of the total energy output from the AGNs into jet kinetic energy versus radiant energy than do FR 2 sources. If this interpretation is correct, then this suggests that there is a fundamental difference in the central engine and/or in the immediate "accretion region" around the engine in FR 1 and FR 2 radio galaxies. We note also the absence of FR 1 sources with nuclear broad line regions and suggest that the absence of the BLR is tied to the absence of the "isotropic" nuclear UV continuum source in FR 1 sources. We put forth the possibility that the FR 1/FR 2 dichotomy (i.e., the observed differences in the properties of low- and high-power radio sources) is due to qualitative differences in the structural properties of the central engines in these two types of sources. Following early work by Rees et al. (1982), we suggest the possibility that FR 1 sources are produced when the central engine is fed at a lower accretion rate, leading to the creation of a source in which the ratio of radiant to jet bulk kinetic energy is low, while FR 2 sources are produced when the central engine is fed at a higher accretion rate, causing the central engine to deposit a higher fraction of its energy in radiant energy. We further suggest the possibility that associated differences in the spin properties of the central black hole between FR 1 (lower spin) and FR 2 (higher spin) sources may be responsible for the different collimation properties and Mach numbers of the jets produced by these two types of radio-loud galaxies. This scenario, although currently clearly speculative, is nicely consistent with our current picture of the triggering, feeding, environments, and evolution of powerful radio galaxies. This model allows for evolution of these properties with time for example, the mass accretion rate and BH spin may decline with time causing an FR 2 radio source or quasar to evolve into a FR 1 radio source.

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

    PubMed

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

    2015-02-01

    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

  11. The cool component and the dichotomy, lateral expansion, and axial rotation of solar X-ray jets

    SciTech Connect

    Moore, Ronald L.; Sterling, Alphonse C.; Falconer, David A.; Robe, Dominic

    2013-06-01

    We present results from a study of 54 polar X-ray jets that were observed in coronal X-ray movies from the X-ray Telescope on Hinode and had simultaneous coverage in movies of the cooler transition region (T ∼ 10{sup 5} K) taken in the He II 304 Å band of the Atmospheric Imaging Assembly (AIA) on Solar Dynamics Observatory. These dual observations verify the standard-jet/blowout-jet dichotomy of polar X-ray jets previously found primarily from XRT movies alone. In accord with models of blowout jets and standard jets, the AIA 304 Å movies show a cool (T ∼ 10{sup 5} K) component in nearly all blowout X-ray jets and in a small minority of standard X-ray jets, obvious lateral expansion in blowout X-ray jets but none in standard X-ray jets, and obvious axial rotation in both blowout X-ray jets and standard X-ray jets. In our sample, the number of turns of axial rotation in the cool-component standard X-ray jets is typical of that in the blowout X-ray jets, suggesting that the closed bipolar magnetic field in the jet base has substantial twist not only in all blowout X-ray jets but also in many standard X-ray jets. We point out that our results for the dichotomy, lateral expansion, and axial rotation of X-ray jets add credence to published speculation that type-II spicules are miniature analogs of X-ray jets, are generated by granule-size emerging bipoles, and thereby carry enough energy to power the corona and solar wind.

  12. Towards self-consistent modelling of the Martian dichotomy: The influence of one-ridge convection on crustal thickness distribution

    NASA Astrophysics Data System (ADS)

    Keller, T.; Tackley, P. J.

    2009-04-01

    In order to find a possible explanation for the origin of the Martian crustal dichotomy, a number of recent papers have examined the effect of layered viscosity on the evolution of a degree-1 mantle convection, e.g. [1] and [2]. It was found that a mid-mantle viscosity jump in the Martian mantle, combined with highly temperature- and depth-dependent viscosity, are effective in developing a degree-1 convection within 200-300 Million years of core formation. Such a layered viscosity profile could be justified by Martian mineralogy, where both olivine to spinel and garnet/pyroxene to majorite transitions occur below a mantle depth of 1000 km. All of these high-pressure mineral phases show higher strength than their corresponding upper mantle phases and thus a higher viscosity might be expected. However, the actual effect of a degree-1 convective planform on the crustal thickness distribution has not yet been demonstrated. Also, the general shape of the dichotomy, which is not symmetrically hemispherical, has not yet been fully investigated. In this study we therefore discuss, how the evolution of low-degree mantle convection inside the planet Mars is reflected on its surface in terms of crustal thickness distribution. This will allow us to draw some conclusions towards a possible theory of how the dichotomy was formed in early Martian history. This study involves full planet-scale modelling of the crustal patterns produced by 3D-spherical models of Martian mantle convection. All results are computed using the finite-volume multigrid code StagYY [3]. By using tracer particles to track composition, a self-consistent treatment modelling melting and chemical differentiation has been added to models of thermal convection. This allows us to obtain model maps of the crustal thickness distribution as it evolves with time on the whole planetary surface due to underlying convection patterns. To obtain rapid reduction of convective degree, a strongly depth- and temperature-dependent rheology has been applied with additional viscosity jumps at each mineralogical phase transition. The most striking feature of the results is the fact that the obtained convective planform does not satisfy the expectation of a spherically symmetrical one-plume convection (l=1). It is rather like what we would call one-ridge convection' where the upwelling is a ridge-shaped feature covering a variable angle around the CMB. A closer look at this feature reveals that it consist of two plumes at each end, interlinked by a sheet-like upwelling region of lower intensity. From this point of view, it represents a stable transition state between l=1 and l=2 convection. Most melt in our model runs is generated above the major ridge-shaped upwelling region and thus crustal thickness distribution to a first order reflects the large-scale upwelling pattern in the mantle. Additional melting occurs where small-scale convection is active underneath the rigid lid. Due to this effect, the hemisphere of downwelling is covered by crust, too, but it is remarkably thinner than above major upwellings. Although mean crustal thickness is slightly overestimated in all of our models, the relative distribution of crustal thickness seems to be quite Mars-like. We find that, although absolute values of crustal thickness are above values inverted for Mars, the relative crust distribution of our best-fit model shows intriguing similarity to that obtained from a MOLA crustal thickness model [4]. Although many questions still remain, the obtained results demonstrate that it is indeed possible to form a crustal dichotomy as a consequence of very low degree (l=1 to l=2) mantle convection very early in the planet's history and, furthermore, that some of the observed patterns show intriguing first order similarities to the general non-spherical shape of the Martian dichotomy. In all of our models, the region of thick crust came to be located over the region of mantle upwelling, whereas crustal thinning above upwellings seemed to be a rather minor effect. The region of upwelling itself proves not to be strictly hemispherical, but is rather a ridge-like structure spread over more or less one half of the planet's body. We call this type of convective planform one-ridge convection in analogy to the commonly known term one-plume convection. This one-ridge convection could well turn out to be a successful approach to future, more systematic modelling of the Martian crustal dichotomy. Furthermore, this study demonstrates how important it is to model closely linked processes like thermal convection and melting in an integrative and self-consistent way to gain more insight into terrestrial planetary evolution. References [1] Roberts, J. H. and Zhong, Sh. (2006) JGR, 111, E06013. [2] Yoshida, M. and Kageyama, A. (2006) JGR, 111, B03412. [4] Paul J. Tackley, (2008), PEPI, 171. [5] Neumann, G. A. et al. (2004) JGR, 109, E08002.

  13. Understanding the Dorsal and Ventral Systems of the Human Cerebral Cortex: Beyond Dichotomies

    ERIC Educational Resources Information Center

    Borst, Gregoire; Thompson, William L.; Kosslyn, Stephen M.

    2011-01-01

    Traditionally, characterizations of the macrolevel functional organization of the human cerebral cortex have focused on the left and right cerebral hemispheres. However, the idea of left brain versus right brain functions has been shown to be an oversimplification. We argue here that a top-bottom divide, rather than a left-right divide, is a more…

  14. The Smoking Gun: Remanent Magnetic Anomalies on Mars and the Formation of the Crustal Dichotomy via Giant Impact

    NASA Astrophysics Data System (ADS)

    Dombard, A. J.; Johnson, C. L.

    2011-12-01

    The formation of large-scale crustal magnetic anomalies in the Southern Highlands of Mars is equivocal. Though some are indeed elongated primarily in the east-west direction, initial map projections exacerbated their linear nature, leading to the hypothesis that the anomalies are equivalent to magnetic stripes due to spreading of Earth's sea floor and hence to the proposal of plate tectonics on Mars. This interpretation, however, is inconsistent with Martian geology. For instance, a plate-tectonics model predicts the anomalies should be formed in thin, oceanic crust at low elevation, but instead they are found in the thick crust of the Highlands, not in the thin crust of the Northern Lowlands. Indeed, the formation of this Crustal Dichotomy is also equivocal, with models ranging from a giant impact (or multiple smaller impacts) near either the current north or south poles, to plate tectonics-like processes, to mantle convection, either eroding the crust in the northern hemisphere or thickening the crust in the south. Recently, the idea of a giant impact in the north has been resurrected, with the proposal that the Dichotomy results from the formation of an elliptical basin by a giant impact very early in Martian history. While it may be tempting to suggest that the current, generally demagnetized state of the Northern Lowlands may be related to this impact, this linkage makes implicit assumptions about the timing of dynamo shut-off on Mars, and it neglects other demagnetization mechanisms possibly operating in the Lowlands after such an impact (e.g., later hydrothermal processing). More direct magnetic evidence for the giant impact hypothesis would come if the remanent magnetism in Southern Highlands were relatable in a unique way to the putative impact. Here, we show that the positions of many of the dominant elongated magnetic anomalies on Mars are consistent with the first ring of a multi-ring basin. The best match comes from an ellipse ~2200 km wider than the inferred boundary of the basin. This distance is the square root of 2 minus 1 of the long axis, and root-2 spacing is characteristic of the inward dipping normal faults in multi-ring basins. The constant distance of our predicted ring, as opposed to variable spacing due to the elliptical nature of the basin, is also consistent with the idea that multi-ring basins form from stress release during inward collapse of the transient crater. Because of the size of the basin, the second ring would be found in the antipodal region, where its formation is dubious and where seismic focusing from the impact has been proposed to explain the generally absent magnetic anomalies in the south polar region. The observation that the elongated magnetic anomalies on Mars mark the first ring around a basin both provides an explanation for the formation of many of the anomalies, and supports the hypothesis that the Crustal Dichotomy of Mars is the product of a giant impact that formed an elliptical basin.

  15. Towards self-consistent modelling of the Martian dichotomy: The influence of one-ridge convection on crustal thickness distribution

    NASA Astrophysics Data System (ADS)

    Keller, T.; Tackley, P. J.

    2008-09-01

    Introduction In order to find a possible explanation for the origin of the Martian crustal dichotomy, a number of recent papers have examined the effect of layered viscosity on the evolution of a degree-1 mantle convection, e.g. [1] and [2]. It was found that a mid-mantle viscosity jump in the Martian mantle, combined with highly temperature- and depth-dependent viscosity, are effective in developing a degree-1 convection within 200-300 Million years of core formation. Such a layered viscosity profile could be justified by Martian mineralogy, where both olivine to spinel and garnet/pyroxene to majorite transitions occur below a mantle depth of 1000 km. All of these high-pressure mineral phases show higher strength than their corresponding upper mantle phases and thus a higher viscosity might be expected [3]. However, the actual effect of a degree-1 convective planform on the crustal thickness distribution has not yet been demonstrated. So far, it has not been obvious whether a thinner crust, due to sublithospheric erosion and crustal thinning, or a thicker crust, due to enhanced crustal production, would form above the hemisphere of mantle upwelling. Also, the general shape of the dichotomy, which is not symmetrically hemispherical, has not yet been fully investigated. In this study we therefore discuss, how the evolution of low-degree mantle convection inside the planet Mars is reflected on its surface in terms of crustal thickness distribution. This will allow us to draw some conclusions towards a possible theory of how the dichotomy was formed in early Martian history. Method This study involves full planet-scale modelling of the crustal patterns produced by 3D-spherical models of Martian mantle convection. All results are computed using the finitevolume multigrid code StagYY [4]. By using tracer particles to track composition, a self-consistent treatment modelling melting and chemical differentiation has been added to models of thermal convection. This allows us to obtain model maps of the crustal thickness distribution as it evolves with time on the whole planetary surface due to underlying convection patterns. To obtain rapid reduction of convective degree, a strongly depth- and temperature-dependent rheology has been applied with additional viscosity jumps at each mineralogical phase transition. See Fig. 1 for a typical viscosity profile used in this study. Results and Discussion Due to very expensive computation (3.5 Million gridpoints, 50 Million tracer particles), the parameter range for this study has to be rather narrow. The results of the model runs display a number of consitent features appearing over the examined range of Rayleigh numbers (3.107 to 7.107) and initial temperatures (1500 K to 1600 K). The most striking of the results is not only the fact, that convection rapidly (<200 Myr) evolves into a pattern of very low degree but also that the obtained convective planform, does not satisfy the expectation of a spherically symmetrical one-plume convection (l=1). It is rather like what we would call oneridge convection (see Fig. 2) where the upwelling is a ridgeshaped feature covering a variable angle around the CMB. A closer look at this feature reveals that it consist of two plumes at each end, interlinked by a sheet-like upwelling region of lower intensity. From this point of view, it represents a stable transition state between l=1 and l=2 convection. Most melt in our model runs is generated above the major ridge-shaped upwelling region and thus crustal thickness distribution to a first order reflects the large-scale upwelling pattern in the mantle. Additional melting occurs where small-scale convection is active underneath the rigid lid. Due to this effect, the hemisphere of downwelling is covered by crust, too, but it is remarkably thinner than above major upwellings (Fig. 2). Although mean crustal thickness is slightly overestimated in all of our models, the relative distribution of crustal thickness seems to be quite Marslike. To analyze crustal structure of some of our model runs, we plot histograms of crustal thickness distribution (Fig. 3) and compare it as a reference to a model Martian crust obtained by inverting Mars Orbiter Laser Altimetry (MOLA) topography and gravity data collected by Mars Global Surveyor spacecraft [5]. We find that, although absolute values of crustal thickness are above values inverted for Mars, the relative crust distribution of our best fit model (upper right side in Fig. 3) still shows intriguing similarity to the MOLA model. In fact, the step between the two distinct peaks representing northern lowlands and southern highlands, is the same (26 km) for both our best fit model as well as for MOLA data. Conclusions Although many questions still remain, the obtained results demonstrate that it is indeed possible to form a crustal dichotomy as a consequence of very low degree (l=1 to l=2) mantle convection very early in the planets history and, furthermore, that some of the observed patterns also show intriguing and unexpected first order similarities to the general non-spherical shape of the Martian dichotomy. In all of our models, the region of thick crust came to be located over the region of mantle upwelling, whereas crustal thinning above upwellings seemed to be a rather minor effect. The region of upwelling itself proves not to be strictly hemispherical, but is rather a ridge-like structure spread over more or less one half of the planets body. We call this type of convective planform one-ridge convection in analogy to the commonly known term one-plume convection. This one-ridge convection could well turn out to be a succesfull approach to future, more systematic modelling of the Martian crustal dichotomy. Furthermore, this study demonstrates how important it is to model closely linked processes like thermal convection and melting in an integrative and self-consistent way to gain more insight into terrestrial planetary evolution. Therefore, more ongoing work also focuses on the effect of a combined intrusion-extrusion magmatic model, which we expect to refine future modelling.References [1] Roberts, J. H. and Zhong, Sh. (2006) JGR, 111, E06013. [2] Yoshida, M. and Kageyama, A. (2006) JGR, 111, B03412. [3] Meade, Ch. and Jeanloz, R. (1990) Nature, 348, 533- 535. [4] Tackley, P. J. (2008) PEPI, submitted. [5] Neumann, G. A. et al. (2004) JGR, 109, E08002.

  16. The Dichotomy of Tumor Exosomes (TEX) in Cancer Immunity: Is It All in the ConTEXt?

    PubMed Central

    Kunigelis, Katherine E.; Graner, Michael W.

    2015-01-01

    Exosomes are virus-sized nanoparticles (30–130 nm) formed intracellularly as intravesicular bodies/intralumenal vesicles within maturing endosomes (“multivesicular bodies”, MVBs). If MVBs fuse with the cell’s plasma membrane, the interior vesicles may be released extracellularly, and are termed “exosomes”. The protein cargo of exosomes consists of cytosolic, membrane, and extracellular proteins, along with membrane-derived lipids, and an extraordinary variety of nucleic acids. As such, exosomes reflect the status and identity of the parent cell, and are considered as tiny cellular surrogates. Because of this closely entwined relationship between exosome content and the source/status of the parental cell, conceivably exosomes could be used as vaccines against various pathologies, as they contain antigens associated with a given disease, e.g., cancer. Tumor-derived exosomes (TEX) have been shown to be potent anticancer vaccines in animal models, driving antigen-specific T and B cell responses, but much recent literature concerning TEX strongly places the vesicles as powerfully immunosuppressive. This dichotomy suggests that the context in which the immune system encounters TEX is critical in determining immune stimulation versus immunosuppression. Here, we review literature on both sides of this immune coin, and suggest that it may be time to revisit the concept of TEX as anticancer vaccines in clinical settings. PMID:26694473

  17. Dichotomy in the Epigenetic Mark Lysine Acetylation is Critical for the Proliferation of Prostate Cancer Cells

    PubMed Central

    Pathak, Ravi; Philizaire, Marc; Mujtaba, Shiraz

    2015-01-01

    The dynamics of lysine acetylation serve as a major epigenetic mark, which regulates cellular response to inflammation, DNA damage and hormonal changes. Microarray assays reveal changes in gene expression, but cannot predict regulation of a protein function by epigenetic modifications. The present study employs computational tools to inclusively analyze microarray data to understand the potential role of acetylation during development of androgen-independent PCa. The data revealed that the androgen receptor interacts with 333 proteins, out of which at least 92 proteins were acetylated. Notably, the number of cellular proteins undergoing acetylation in the androgen-dependent PCa was more as compared to the androgen-independent PCa. Specifically, the 32 lysine-acetylated proteins in the cellular models of androgen-dependent PCa were mainly involved in regulating stability as well as pre- and post-processing of mRNA. Collectively, the data demonstrate that protein lysine acetylation plays a crucial role during the transition of androgen-dependent to -independent PCa, which importantly, could also serve as a functional axis to unravel new therapeutic targets. PMID:26295410

  18. Fourteenth Annual Pezcoller Symposium: the novel dichotomy of immune interactions with tumors.

    PubMed

    Hanahan, Douglas; Lanzavecchia, Antonio; Mihich, Enrico

    2003-06-01

    The main focus of the Symposium was the fact that cell types of the innate and adaptive immune systems can have tumor-favoring as well as tumor antagonistic effects, both in a preventive and therapeutic mode. It was shown that macrophages (Mphi) and dendritic cells within a tumor exert tumor-favoring effects through the action of certain cytokines. Inflammatory reactions could favor the onset and growth of tumors. Dual immune functions were shown with CD4+ T cells and certain matrix metalloproteinase (MMP) activities favoring tumor progression and CD8+ T cells and certain heat shock proteins having antitumor action. Lack of antitumor action despite positive immune stimulation was also shown to depend on the existence of barriers to tumor infiltration by lymphocytes; remodeling of vasculature, e.g., by IFNgamma-induced cytokines like MIG and IPIO, reversed this type of impediment. Certain CXC cytokines increased tumor progression, whereas others, particularly those induced by IFNgamma, had the opposite effect; stromal-derived factor-1 and its receptor CXCR4 affected tumor propensity to metastasize in certain organs. Stromal-derived factor-1 induced MMP9, which in turn regulated the bioavailability of vascular endothelial growth factor and the cascade of its tumor-favoring effects, whereas granulocyte colony-stimulating factor decreased MMP9 and the consequences of its action. The effects of certain proinflammatory cytokines and vascular endothelial growth factor functions in angiogenesis and lymphoangiogenesis were also discussed. The favoring effects of fever-like thermal stress on the function of molecules instrumental in lymphoid cell adhesion to vessels and infiltration into sites of immune actions were described. The mechanisms involved in the development of immune memory and those conditioning Type I and CTL responses were also discussed. A number of presentations were concerned with laboratory studies aimed at developing clinical regimens with potential activity in the prevention or treatment of cancer. Prevention of Her2/neu breast cancer in transgenic mice was achieved by suitable regimens with IL12 combined with vaccines, including DNA-based vaccines administered in conjunction with electroporation. Vaccination with shared tumor antigen MUCI or cyclin B was discussed, and its clinical translation was described. The prevention of TRAMP prostate tumor in transgenic mice by anti-CTLA4 antibody plus vaccine was described, as was the translation of these regimens to the clinics. Clinical successes in melanoma patients using antimelanoma antigen antibodies in a therapeutic mode and precautions to be exerted in evaluating in vivo immune responses based on in vitro assays were emphasized. The symposium was concluded with an overall discussion focused on basic questions related to the capability of immunity to exert tumor-favoring or antitumor effects depending on conditions determined by both tumor and host functions. PMID:12782611

  19. Towards self-consistent modelling of the Martian dichotomy: Coupled models of simultaneous core and crust formation

    NASA Astrophysics Data System (ADS)

    Keller, T.; Golabek, G.; Gerya, T. V.; Connolly, J.

    2009-04-01

    One of the most striking surface features on Mars is the crustal dichotomy. The crustal dichotomy, a large difference in elevation and crustal thickness between the southern highlands and the northern lowlands, is the oldest geological feature on Mars. It was formed more than 4.1 Ga ago [Solomon et al., 2005; Nimmo and Tanaka, 2005; Frey, 2006] owing to either exogenic [e.g. Nimmo et al., 2008; Andrews-Hanna et al., 2008] or endogenic processes [e.g. Zhong and Zuber, 2001; Roberts and Zhong, 2006; Keller and Tackley, 2009]. Based on the geochemical analysis of SNC meteorites it was suggested that a primordial crust with up to 45 km thickness can be formed already during the Martian core formation [Norman, 1999]. The final accretion stage of terrestrial planets is based on stochastically distributed impacts [e.g. Chambers, 2004; Rubie et al., 2007]. Therefore we suggest that the sinking of iron diapirs, delivered by late pre-differentiated impactors, might have induced shear heating-related temperature anomalies in the mantle, which fostered the formation of early Martian crust. In this study, we examine parameter sets that will likely cause an onset of hemispherical low-degree mantle convection directly after, and coupled to, an already asymmetrical core formation. To test this hypothesis we use a numerical model, where we self-consistently couple the formation of the Martian iron core to the onset of mantle convection and crust formation. We perform 2D spherical simulations using the code I2ELVIS applying the newly developed "spherical-Cartesian" methodology [Gerya and Yuen, 2007]. It combines finite differences on a fully staggered rectangular Eulerian grid and Lagrangian marker-in-cell technique for solving momentum, continuity and temperature equations as well as Poisson equation for gravity potential in a self-gravitating planetary body. In this model, the planet is surrounded by a low viscosity, massless fluid ("sticky air") to simulate a free surface [Schmeling et al., 2008]. Previous studies showed that the convection patterns in the Martian mantle are highly dependent on its effective viscosity structure [e.g. Harder and Christensen, 1996; Keller and Tackley, 2009]. Therefore we apply a temperature, stress- and phase-dependent viscoplastic rheology inside a Mars-sized planet and include radioactive-, shear- and adiabatic heating. As initial condition we employ randomly distributed diapirs with 75 km radius inside the accreting planet, which represent the iron delivered by predifferentiated impactors. Additionally, we explore the effect of a giant impactor core on the planetary evolution. To self-consistently simulate the mineralogical phase changes expected inside a Mars-sized body, we employ the thermodynamical PerpleX database [Connolly, 2005]. First results indicate that both the presence of one large impactor core and viscosity layering due to phase-dependent rheology might induce low-degree convection already during core formation. Furthermore, the amplitude of shear heating anomalies generally well exceeds the solidus of primitive mantle material. Therefore the formation of a considerable amount of melt is to be expected. Since preliminary studies indicate that most heat is released at mid-mantle depth, some of the generated melt will segregate to the surface to form basaltic crust, whereas negatively buoyant melt from deeper sources will sink to the CMB. The depth of neutral buoyancy will be determined by the difference in compressibility of melt relative to solid silicates. Both the hemispherical asymmetry induced by a giant impactor as well as the low-degree pattern of convection caused by phase-dependent viscosity may therefore contribute to an early evolution of a dichotomous crustal thickness distribution.

  20. Towards self-consistent modelling of the Martian dichotomy: Coupled models of simultaneous core and crust formation

    NASA Astrophysics Data System (ADS)

    Golabek, Gregor; Keller, Tobias; Gerya, Taras; Zhu, Guizhi; Tackley, Paul

    2010-05-01

    One of the most striking surface features on Mars is the crustal dichotomy. It is the oldest geological feature on Mars and was formed more than 4.1 Ga ago by either exogenic or endogenic processes (e.g. Keller and Tackley, 2009). In order to find an internal origin of the crustal dichotomy, located within a maximum of 400 Ma of planetary differentiation, the thermal state of the planet resulting from core formation needs to be considered. Additionally, it was suggested that a primordial crust with up to 45 km thickness can be formed already during the Martian core formation (Norman, 1999). We suggest that the sinking of iron diapirs delivered by pre-differentiated impactors induced impact- and shear heating-related temperature anomalies in the mantle that fostered the formation of early Martian crust. Thus, the crustal thickness distribution would largely be a result of planetary core formation, late impact history and the onset of mantle convection. In this study, we examine parameter sets that will likely cause hemispherical asymmetry in both core formation and onset of mantle convection. To test this hypothesis we use numerical models to simulate the formation of the Martian iron core and the resulting mantle convection pattern, while peridotite melting is enabled to track melting caused by shear and radioactive heating.
We perform 2D simulations using the spherical-Cartesian code I2ELVIS (Gerya and Yuen, 2007) for planetary accretion and the spherical code STAGYY (Tackley, 2008) for the consequent onset of mantle convection. We apply a temperature-, stress- and melt-fraction dependent viscoplastic rheology inside a Mars-sized planet. Radioactive and shear heating as well as consumption of latent heat by silicate melting are taken into account. The depth of neutral buoyancy of silicate melt with respect to solid silicates is determined by the difference in compressibility of the liquid and solid phase. To self-consistently simulate the silicate phase changes expected inside a Mars-sized body, we use the thermodynamical database PerpleX (Connolly, 2005). As initial condition for core formation (I2ELVIS), we apply randomly distributed iron diapirs with 75 km radius inside the planet, representing the cores of stochastically distributed impactors. Additionally, we explore the effect of one giant impactor core on the planetary evolution. Results indicate that the presence of a large impactor core induces hemispherically asymmetrical core formation. The amplitude of shear heating anomalies often exceeds the solidus of primitive mantle material and thus, the formation of a considerable amount of silicate melt is observed. The resulting temperature field after core formation is then read into the mantle convection code STAYY. The hemispherical magma ocean induced by one late giant impactor favours a dichotomous crust formation during a few Ma after core formation. Afterwards, the extraction of excess heat produced by the sinking of the giant impactor through the mantle leads to a localized region of massive magmatism, comparable to Tharsis, whereas the rest of the mantle is dominated by a sluggish convection pattern with limited crust formation that prevails during the further evolution of the planet. REFERENCES
 Connolly, J.A.D. 2005. EPSL, 236. Gerya, T.V. & Yuen, D.A. 2007. PEPI, 163. Keller, T. & Tackley, P.J. 2009. Icarus, 202. Norman, M.D. 1999. Meteorit. Planet. Sci., 34. Tackley, P.J. 2008. PEPI, 171.

  1. Towards self-consistent modelling of the Martian dichotomy: Coupled models of simultaneous core and crust formation

    NASA Astrophysics Data System (ADS)

    Keller, T.; Golabek, G. J.; Gerya, T.; Connolly, J.

    2009-12-01

    One of the most striking surface features on Mars is the crustal dichotomy. It is the oldest geological features on Mars and was formed more than 4.1 Ga ago by either exogenic or endogenic processes (e.g. Keller and Tackley, 2009). In order to find an internal origin of the crustal dichotomy, located within a maximum of 400 Ma of planetary differentiation, the thermal state of the planet resulting from core formation needs to be considered. It was suggested that a primordial crust with up to 45 km thickness can be formed already during the Martian core formation (Norman, 1999). Therefore we suggest that the sinking of iron diapirs delivered by pre-differentiated impactors induced impact- and shear heating-related temperature anomalies in the mantle that fostered the formation of early Martian crust. In this study, we examine parameter sets that will likely cause an onset of hemispherical low-degree mantle convection directly after, and coupled to, an already hemispherical core formation. To test this hypothesis we use a numerical model to simulate the formation of the Martian iron core, while peridotite melting is enabled to track melting caused by shear and radioactive heating. We perform 2D simulations using the spherical-Cartesian code I2ELVIS (Gerya and Yuen, 2007). It combines finite differences on a fully staggered rectangular Eulerian grid with Lagrangian marker-in-cell technique. In our model setup, the planet is surrounded by a low viscosity, massless fluid (“sticky air”) to simulate a free surface. We apply a temperature- and stress-dependent viscoplastic rheology inside a Mars-sized planet. Radioactive and shear-heating as well as consumption of latent heat by silicate melting are taken into account. The depth of neutral buoyancy of silicate melt with respect to solid silicates is determined by the difference in compressibility of the liquid and solid phase. To self-consistently simulate the silicate phase changes expected inside a Mars-sized body, we use the thermodynamical database Perple_X (Connolly, 2005). As initial condition, we apply randomly distributed iron diapirs with 75 km radius inside the planet, representing the cores of stochastically distributed impactors. Additionally, we explore the effect of one giant impactor core on the planetary evolution. Results indicate that the presence of a large impactor core induces hemispherically asymmetrical core formation. Furthermore, the amplitude of shear heating anomalies often exceeds the solidus of primitive mantle material. The formation of a considerable amount of silicate melt is observed. Some of the generated melt segregates to the surface to form primordial crust, whereas negatively buoyant melt from deeper sources sinks to the CMB. The hemispherical asymmetry in temperature induced by a giant impactor works in favour of an onset of low-degree mantle convection after core formation. Such a hemispherical convection geometry might subsequently be sustained by phase-dependent viscosity (Keller and Tackley, 2009), and thus harbor an early evolution of a dichotomous crustal thickness distribution. REFERENCES Connolly, J.A.D. 2005. EPSL, 236. Gerya, T.V. & Yuen, D.A. 2007. PEPI, 163. Keller, T. & Tackley, P.J. 2009. Icarus, 202. Norman, M.D. 1999. Meteorit. Planet. Sci., 34.

  2. Volume-limited SDSS/First quasars and the radio dichotomy

    SciTech Connect

    Sebastian Jester; R.G. Kron

    2004-03-12

    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 {le} 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.

  3. A quasi-universal medium to break the aerobic/anaerobic bacterial culture dichotomy in clinical microbiology.

    PubMed

    Dione, N; Khelaifia, S; La Scola, B; Lagier, J C; Raoult, D

    2016-01-01

    In the mid-19th century, the dichotomy between aerobic and anaerobic bacteria was introduced. Nevertheless, the aerobic growth of strictly anaerobic bacterial species such as Ruminococcus gnavus and Fusobacterium necrophorum, in a culture medium containing antioxidants, was recently demonstrated. We tested aerobically the culture of 623 bacterial strains from 276 bacterial species including 82 strictly anaerobic, 154 facultative anaerobic, 31 aerobic and nine microaerophilic bacterial species as well as ten fungi. The basic culture medium was based on Schaedler agar supplemented with 1 g/L ascorbic acid and 0.1 g/L glutathione (R-medium). We successively optimized this media, adding 0.4 g/L uric acid, using separate autoclaving of the component, or adding haemin 0.1 g/L or α-ketoglutarate 2 g/L. In the basic medium, 237 bacterial species and ten fungal species grew but with no growth of 36 bacterial species, including 22 strict anaerobes. Adding uric acid allowed the growth of 14 further species including eight strict anaerobes, while separate autoclaving allowed the growth of all tested bacterial strains. To extend its potential use for fastidious bacteria, we added haemin for Haemophilus influenzae, Haemophilus parainfluenzae and Eikenella corrodens and α-ketoglutarate for Legionella pneumophila. This medium allowed the growth of all tested strains with the exception of Mycobacterium tuberculosis and Mycobacterium bovis. Testing primoculture and more fastidious species will constitute the main work to be done, but R-medium coupled with a rapid identification method (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) will facilitate the anaerobic culture in clinical microbiology laboratories. PMID:26577141

  4. Neuroanatomical dichotomy of sexual behaviors in rodents: a special emphasis on brain serotonin

    PubMed Central

    Angoa-Pérez, Mariana; Kuhn, Donald M.

    2016-01-01

    Much of the social behavior in which rodents engage is related to reproduction, such as maintaining a breeding territory, seeking mates, mating, and caring for young. Rodents belong to the internally fertilizing species that require sexual behavior for reproduction. The dyadic, heterosexual patterns of most mammalian species are sexually dimorphic, but they also share mutual components in both sexes: sexual attraction is reciprocal, sexual initiative is assumed, appetitive behavior is engaged in and mating involves consummatory and postconsummatory phases in females as well as in males. Serotonin, a phylogenetically ancient molecule, is the most widely distributed neurotransmitter in the brain and its signaling pathways are essential for numerous functions including sexual behavior. Since the late 1960’s, brain serotonergic neurotransmission has been considered to exert an inhibitory influence on the neural mechanisms mediating sexual behavior. This contention was based mainly on the observations that a decrease in central serotonergic activity facilitated the elicitation of sexual behavior while an increase in central serotonergic activity attenuated it. However, the discovery of over 14 types of serotonin receptors has added numerous layers of complexity to the study of serotonin and sexual behavior. Evidence shows that upon activation, certain receptor subtypes facilitate while some others suppress sexual behavior as well as sexual arousal and motivation. Furthermore, the role of these receptors has been shown to be differential in males versus females. The use of serotonergic pharmacological interventions, mouse strains with genetic polymorphisms causing alterations in the levels of brain serotonin as well as animal models with genetic manipulations of various serotonin effectors has helped delineate the fundamental role of this neurotransmitter in the regulation of sexual behavior. This review aims to examine the basics of the components of female and male sexual behavior and the participation of the serotonin system in the modulation of these behaviors with emphasis on rodents. PMID:26110223

  5. The Urban/Rural Dichotomy in the Distribution of Breast Cancer Across Pennsylvania.

    PubMed

    Boukovalas, Stefanos; Sariego, Jack

    2015-09-01

    Breast cancer rates clearly differ across the United States. This is due to a variety of factors, but at least one determinant is the population density. Breast cancer detection rates and treatment paradigms may differ in rural areas when compared with more urban ones. As the population becomes more mobile and diffuse, this may or may not be a worsening problem. The current analysis was undertaken to examine the breast cancer incidence and outcomes in a single state in an attempt to plan for resource allocation in the future. A retrospective analysis was performed using data available from the Pennsylvania Department of Health regarding breast cancer rates by county, the distribution of cases with regard to degree of rurality, death rates by county as a function of rurality, and the age distribution of all presenting cases. Data from 1999 were compared with those of 2009. The United States Census Bureau definition of rurality was used, which specifies that a county be classified as rural if the population density is less than 284 persons/square mile. Between 1999 and 2009, the population of Pennsylvania increased by approximately 3.4 per cent (421,325 people). The urban population increased by 3.9 per cent, whereas the rural population increased by only 2.2 per cent. During that same period, the number of cancer cases/100,000 population remained about the same: 391.41 in 1999; 390.7 in 2009. However, the distribution of cases shifted during that time toward more rural areas of the state: in 1999, there were 372.3 breast cancer cases/100,000 population compared with 2009 when the rate was 384.4/100,000 population. The number of cancer deaths/100,000 population actually dropped overall during the decade: 98.5 in 1999 versus 82.3 in 2009. Though this was true in both urban and rural counties, the decrease was much less pronounced in the rural areas. In urban counties, the death rate dropped from 100.5 to 81.5/100,000 population, whereas in rural counties, the drop was only from 93.3 to 84.3. The greater increase in cases diagnosed in rural areas of Pennsylvania is only partially explained by the relatively greater increase in rural population. There are undoubtedly other issues at work in rural areas: environmental factors, diffusion of resources, less access to surveillance programs. In addition, though the death rate has dropped in both rural and urban areas, this is much less pronounced in rural counties. Coupled with the increase in prevalence in those areas, this suggests that breast cancer care may be lagging in rural areas. There is a need to examine allocation of resources and surveillance programs. PMID:26350666

  6. Madonna: Like a Dichotomy.

    ERIC Educational Resources Information Center

    Burns, Gary; Kizer, Elizabeth

    Students in communication classes find it useful to study Madonna because she is a fascinating and prolific cultural figure whose merit and intentions are matters of great controversy. As the quintessential music-video star, she is also perhaps the medium's most significant auteur. In the areas of women's roles, motherhood, sexuality, race and…

  7. 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)

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

    2005-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

    2006-12-01

    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 μm 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 τ=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.

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

    USGS Publications Warehouse

    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

    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.

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

    PubMed Central

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

    2015-01-01

    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

  11. Dichotomy Between the age of the Penultimate Glaciation for Different Source Areas of the Northern Cordilleran Ice Sheet, Yukon Territory, Canada.

    NASA Astrophysics Data System (ADS)

    Ward, B. C.; Bond, J. D.; Gosse, J. C.

    2006-12-01

    Terrestrial in situ cosmogenic 10Be was measured to date large boulders that were exposed following deglaciation of the penultimate glaciation of the Cordilleran ice sheet (CIS) in western Yukon Territory, Canada. Ages of 54-51 ka indicate a Marine Oxygen Isotope Stage (MIS) 4 (early Wisconsinan) age for this glaciation, the first such confirmed evidence in the Canadian Cordillera. These results are in apparent contrast to the MIS 6 age of the penultimate Reid glaciation to the east in central Yukon, but are equivalent to exposure ages on penultimate drift in Alaska. Thus there is a dichotomy between MIS 4 and 6 glacial extents for at least two of the source areas for the northern portion of Cordilleran ice sheet, the St. Elias - Coast mountains lobes and the more easterly Selwyn Lobe, indicating different responses to climatic forcing during glaciations. The northern CIS was a precipitation-limited system and we propose variation in regional moisture, specifically how moisture penetrates the St. Elias and Coast mountains, as the possible cause of the dichotomy between glacial advances. Causes for regional variation in precipitation remain unclear but likely involve the style of precipitation delivery over the St. Elias Mountains as controlled by the extent of the Laurentide Ice Sheet and broad variations in position and intensity of the Aleutian Low. When the Aleutian Low is well developed and/or more easterly, meridional flow occurs. This results in strengthened moisture flux from the Pacific, and an increase in the size of the rain shadow. When the Aleutian Low is weaker and/or located further west, atmospheric flow is more zonal, with flow westward over the St. Elias/Coast mountains. There is a reduced moisture flux but the orographic affect is reduced as is the size and magnitude of the rain shadow. Zonal conditions were used to explain periods during the Holocene when O-isotopes indicated more effective precipitation in the present rain shadow area. A similar situation could have prevailed during MIS 4, allowing relatively extensive glacier growth on the leeward side of the St. Elias and Coast mountains. MIS 6 may have had more meridional flow, causing a well-developed rain shadow but still allowing subsequent growth of glaciers in the Selwyn Mountains. Future work will focus on long speleothem records from various localities in Yukon and using a combination of Terrestrial Cosmogenic Nuclides and U-Th dating of pedogenic calcite in soils formed on what has previously been mapped as the same penultimate surface.

  12. Stable symbionts across the HMA-LMA dichotomy: low seasonal and interannual variation in sponge-associated bacteria from taxonomically diverse hosts.

    PubMed

    Erwin, Patrick M; Coma, Rafel; López-Sendino, Paula; Serrano, Eduard; Ribes, Marta

    2015-10-01

    Marine sponges host bacterial communities with important ecological and economic roles in nature and society, yet these benefits depend largely on the stability of host-symbiont interactions and their susceptibility to changing environmental conditions. Here, we investigated the temporal stability of complex host-microbe symbioses in a temperate, seasonal environment over three years, targeting sponges across a range of symbiont density (high and low microbial abundance, HMA and LMA) and host taxonomy (six orders). Symbiont profiling by terminal restriction fragment length polymorphism analysis of 16S rRNA gene sequences revealed that bacterial communities in all sponges exhibited a high degree of host specificity, low seasonal dynamics and low interannual variability: results that represent an emerging trend in the field of sponge microbiology and contrast sharply with the seasonal dynamics of free-living bacterioplankton. Further, HMA sponges hosted more diverse, even and similar symbiont communities than LMA sponges and these differences in community structure extended to core members of the microbiome. Together, these findings show clear distinctions in symbiont structure between HMA and LMA sponges while resolving notable similarities in their stability over seasonal and inter-annual scales, thus providing insight into the ecological consequences of the HMA-LMA dichotomy and the temporal stability of complex host-microbe symbioses. PMID:26405300

  13. Molecular mechanism for opioid dichotomy: bidirectional effect of μ-opioid receptors on P2X₃ receptor currents in rat sensory neurones.

    PubMed

    Chizhmakov, Igor; Kulyk, Vyacheslav; Khasabova, Iryna; Khasabov, Sergey; Simone, Donald; Bakalkin, Georgy; Gordienko, Dmitri; Verkhratsky, Alexei; Krishtal, Oleg

    2015-06-01

    Here, we describe a molecular switch associated with opioid receptors-linked signalling cascades that provides a dual opioid control over P2X3 purinoceptor in sensory neurones. Leu-enkephalin inhibited P2X3-mediated currents with IC50 ~10 nM in ~25% of small nociceptive rat dorsal root ganglion (DRG) neurones. In contrast, in neurones pretreated with pertussis toxin leu-enkephalin produced stable and significant increase of P2X3 currents. All effects of opioid were abolished by selective μ-opioid receptor antagonist D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP), nonselective inhibitor naloxone, and by PLC inhibitor U73122. Thus, we discovered a dual link between purinoceptors and μ-opioid receptors: the latter exert both inhibitory (pertussis toxin-sensitive) and stimulatory (pertussis toxin-insensitive) actions on P2X3 receptors through phospholipase C (PLC)-dependent pathways. This dual opioid control of P2X3 receptors may provide a molecular explanation for dichotomy of opioid therapy. Pharmacological control of this newly identified facilitation/inhibition switch may open new perspectives for the adequate medical use of opioids, the most powerful pain-killing agents known today. PMID:25592684

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

    PubMed

    Singh, Varsha

    2013-01-01

    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

  15. The traditional vs "1:1:1" approach debate on massive transfusion in trauma should not be treated as a dichotomy.

    PubMed

    Ho, Anthony M-H; Holcomb, John B; Ng, Calvin S H; Zamora, Jorge E; Karmakar, Manoj K; Dion, Peter W

    2015-10-01

    Traditional transfusion guidelines suggest that fresh frozen plasma (FFP) should be given based on laboratory or clinical evidence of coagulopathy or acute loss of 1 blood volume. This approach tends to result in a significant lag time between the first units of erythrocytes and FFP in trauma requiring massive transfusion. In severe trauma, observational studies have found an association between increased survival and aggressive use of FFP and platelets such that FFP:platelet:erythrocyte ratio approaches 1:1:1 to 2 from the first units of erythrocytes given. There are considerable concerns over either approach, and no randomized controlled trials have been published comparing the 2 approaches. Nowadays, trauma clinicans are incorporating the strenghts of both approaches and are no longer treating them as a dichotomy. Specifically, "1:1:1" proponents have devised 1:1:1 activation criteria to minimize unnecessary FFP and platelet transfusion and are prepared to deactivate the protocol as soon as patient is stabilized. Similarly, 1:1:1 skeptics are more mindful of the need to be proactive about trauma coagulopathy and the inherent delays in FFP administration in trauma patients. PMID:26184524

  16. 2.5-dimensional model of disk-outflow symbiotic systems: description of FSRQ/BL Lac dichotomy based on Fermi observations

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Banibrata; Bhattacharya, Debbijoy; Parameswaran, Sreekumar

    2012-07-01

    Several observational evidences and deeper theoretical insights reveal that accretion and outflow/jet are strongly correlated. We model an advective disk-outflow coupled dynamics, incorporating explicitly the vertical flux. Inter-connecting dynamics of outflow and accretion essentially upholds the conservation laws. We investigate the properties of the disk-outflow surface and its strong dependence on the rotation parameter of the black hole. The energetics of the disk-outflow strongly depend on the mass, accretion rate and spin of the black holes. The model clearly shows that the outflow power extracted from the disk increases strongly with the spin of the black hole, inferring that the power of the observed astrophysical jets has a proportional correspondence with the spin of the central object. Now blazars are characterized by large intensity and spectral variations across the electromagnetic waveband. Observationally, blazars can be divided into two classes: flat spectrum radio quasars (FSRQs) and BL Lacs. BL Lacs usually exhibit lower luminosity and harder power law spectra at {?}-ray energies than those of FSRQs. We attempt to explain the high energy properties of FSRQs and BL Lacs from Fermi {?}-ray space telescope observations, based on our model. We propose that spin plays an important role in the luminosity distribution dichotomy of BL Lacs and FSRQs.

  17. Relationships of Balance, Gait Performance, and Functional Outcome in Chronic Stroke Patients: A Comparison of Left and Right Lesions

    PubMed Central

    Lopes, Priscila Garcia; Lopes, José Augusto Fernandes; Brito, Christina Moran; Alfieri, Fábio Marcon; Rizzo Battistella, Linamara

    2015-01-01

    Introduction. This study compared the balance by center of pressure (COP) and its relationship with gait parameters and functional independence in left (LH) and right (RH) chronic stroke patients. Methods. In this cross-sectional study, twenty-one hemiparetic stroke patients were assessed for Functional Independence Measure (FIM), balance with a force platform, and gait in the Motion Analysis Laboratory. Results. The amplitudes of the COP in the anteroposterior and mediolateral directions were similar in both groups. The anteroposterior direction was greater than the mediolateral direction. Only the temporal parameters showed any statistically significant differences. The LH showed a significant correlation between stride length, step length, and gait velocity with COP velocity sway for the healthy and paretic lower limbs. In both groups, the area of COP was significantly correlated with stride length. Motor FIM was significantly correlated with the COP in the LH group. Conclusion. There was no difference in the performance of balance, gait, and functional independence between groups. The correlation of the COP sway area with stride length in both groups can serve as a guideline in the rehabilitation of these patients where training the static balance may reflect the improvement of the stride length. PMID:26583129

  18. 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

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

    2014-01-01

    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

  19. Hot versus cold: The dichotomy in spherical accretion of cooling flows onto supermassive black holes in elliptical galaxies, galaxy groups, and clusters

    SciTech Connect

    Guo, Fulai; Mathews, William G.

    2014-01-10

    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 {sub ☉}, 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 {sub 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.

  20. 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

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

    2015-01-01

    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 fluorescence in situ hybridization with only one case exhibiting FUS rearrangement. Of the nine EWSR1 positive cases, six 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

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

    SciTech Connect

    Lopez, Eric D.; Fortney, Jonathan J.

    2013-10-10

    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.

  2. Functional integration across a gradient of corticostriatal channels controls UP state transitions in the dorsal striatum

    PubMed Central

    Kasanetz, Fernando; Riquelme, Luis A.; Della-Maggiore, Valeria; O'Donnell, Patricio; Murer, M. Gustavo

    2008-01-01

    Coordinated near-threshold depolarized states in cortical and striatal neurons may contribute to form functionally segregated channels of information processing. Recent anatomical studies have identified pathways that could support spiraling interactions across corticostriatal channels, but a functional outcome of such spiraling remains to be identified. Here, we examined whether plateau depolarizations (UP states) in striatal neurons relate better to active epochs in local field potentials recorded from closely related cortical areas than to those recorded in less-related cortical areas. Our results show that, in anesthetized rats, the coordination between cortical areas and striatal regions obeys a mediolateral gradient and keeps track of slow wave trajectory across the neocortex. Moreover, activity in one cortical area induced phase advances in UP state onset and phase delays in UP state termination in nonmatching striatal regions, reflecting the existence of functional connections that could encode large-scale interactions between corticostriatal channels as subthreshold influences on striatal projection neurons. PMID:18523020

  3. 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)

    Siegel, Carl Ludwig; Siegel, Edward Carl-Ludwig

    2011-03-01

    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)

  4. 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)

    McAllister, William K.

    2003-01-01

    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.

  5. Comparative morphology of porpoise (Cetacea: Phocoenidae) pterygoid sinuses: phylogenetic and functional implications.

    PubMed

    Racicot, Rachel A; Berta, Annalisa

    2013-01-01

    High-resolution X-ray computed tomographic scans were used to examine pterygoid sinus morphology within extant porpoise species and one delphinid (Tursiops truncatus), in order to consider: 1) intraspecific and interspecific variation among the studied species; 2) the most parsimonious sequence of character acquisition; and 3) the potential functional roles of the preorbital lobes of the sinuses in sound reflection. Scans revealed that the pterygoid/palatine regions are mediolaterally broader in the earliest diverging phocoenid (Neophocaena phocaenoides) and Tursiops truncatus than the dorsoventrally elongated sinuses observed in other species. Rostrocaudal lengths of the sphenoidal regions of the sinuses in all individuals studied are proportionally similar, indicating conservatism in this region across species. The neonate Phocoena phocoena has shorter preorbital lobes than adults, but they are still proportionally longer than Neophocaena phocaenoides and Phocoena spinipinnis. The preorbital lobes broaden mediolaterally to varying degrees across species; in particular, Phocoenoides dalli has the largest dorsal and lateral expansion of this region. Assuming the highest pulse frequency produced by porpoises is 150 kHz, all regions of the preorbital lobes are thick enough to reflect the wavelengths produced. In addition, the neonate preorbital lobes are not as elongated as they are in adults, and the dorsal third of this region may not reflect sound to the same extent. This study reinforces the importance of using nondestructive methods to quantify variation in endocranial anatomy and the value of CT data for recovering phylogenetically useful information, as well as functional roles sinuses play in concert with the soft tissue head anatomy for biosonar. PMID:22965565

  6. Evidence of stratabound liquefaction in the formation of fractured topographic margins, cone chains and pit catenas along the Martian Dichotomy Boundary and in Isidis Planitia, Mars.

    NASA Astrophysics Data System (ADS)

    Gallagher, C.; Balme, M. R.

    2012-04-01

    On the low-lying plains along much of the Martian Dichotomy Boundary (MDB) and in the Isidis impact basin, cones and curving chains of cones, referred to as thumbprint terrain (TPT), are common. In the same settings, pit chains (catenas) occur in orthogonal to curving and conchoidal fracture sets between mesa-like crustal blocks, generally at or near topographic margins. Many of the fractures consist of linked pits rather than simple propagated cracks. These assemblages are often associated with the more disaggregated populations of blocks comprising chaos terrain. We show that the local planimetric arrangement of the cone chains, fractures and pit catenas is strikingly similar in both shape and scale, including lateral separation, length, longitudinal slope and radius of curvature. The summits of cones tend to be closely accordant along individual cone chains. Neighbouring cone chains tend to be mutually accordant on low gradient basin surfaces but generally stepped en echelon closer to the fractured basin margins. Similarly, the crustal blocks (including very isolated block sets) are often mutually stepped, and fractures between these en echelon blocks tend to be very close to horizontal. Hence, many cone chains, fractures and pit catenas in fractures share the property of being arranged along strike. They diverge morphologically by the cone chains being positive forms separated by narrow gulfs but the pit catenas being negative forms separated by planar blocks. All of these characteristics point to the possibility that the arcuate cone chains and the arcuate pit catenas have a common origin. In particular, we hypothesise that the cone chains characteristic of TPT along the MDB and in Isidis are filled, indurated and then exhumed pit catenas revealed by the stripping-away of intervening blocks [cf. 1]. Many other surfaces on Mars are pervaded by pits and pit catenas, with evidence of former water flow through the catenas suggesting that ground-ice thaw played a role in at least one mode of catena formation [2]. As well as presenting the morphological evidence for a genetic association between TPT and pit catenas, we present corroborative evidence that fluvial channel networks on Mars have in places increased in complexity through the linking of pits arranged in linear to arcuate arrays, culminating in a pseudo-branching channel network. Such systems do not occur at topographic margins and did not disintegrate into stepped crustal blocks. However, the scale of these channels and the volumes of liquid intermittently impounded in craters along these channel systems indicate that pit chains are associated with significant excess groundwater production leading to channelized flow, including catastrophic discharges when crater-impounded lakes along-flow were breached. Are the MDB and Isidis cone chains exhumed pit catenas and are the pits the surface expression of more deep-seated conduits? Do pit catenas indicate excess pore-water production, sufficient to link individual pits and dissect crustal blocks? Together, do these assemblages reflect the degradation of the MDB and Isidis margins and the subsequent stripping of adjacent low-lying plains? The crucial observations presented in this research (cone chains lying between crustal blocks, together with the morphometric similarities) are consistent with the interpretation of the cones and catenas having a common origin. Consequently, we hypothesise that the translated, back-rotated, tilted and capsized disposition of en echelon blocks is very reminiscent of the morphology produced during lateral spreading [3] associated with stratabound liquefaction below a low-gradient, rigid, insensitive surface. Significantly, such liquefaction events cause extensive, arcuate ground fractures along with the discharge of sediment-laden groundwater from the liquefiable substratum to the surface through pipes and conical boils confined within inter-block fractures. These conduits and their injectite are frequently indurated by secondary mineralisation, often making them more competent and less erodible than the confining material. Most often, lateral spreads occur at coastlines, with basin-ward normal faulting and extension of the original surface. Generally, seismic shaking of susceptible materials is responsible for lateral spreading but pore-water pressure changes, e.g. due to rapid marine recession and drawdown, may also play a role. Given the basin-and-margin setting of the martian cone, pit and block assemblages described in this research, we speculate that all three broad morphological types reflect the degradation of extensive marine margins and the deflation of the interiors of marine basins during long-term marine recession. [1] Williams et al. (2007) in Willis et al. (eds), Utah Geological Association Publication 36. [2] Weitz et al. (2006) Icarus 184, 436-451. [3] Wang et al. (2005) Icarus 175, 551-555.

  7. 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)

    Clay, L.; Siegel, E.

    2010-03-01

    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.

  8. 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)

    Clay, London; Siegel, Edward Carl-Ludwig

    2011-03-01

    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.

  9. Overcoming the false dichotomy of curative vs palliative care for late-stage HIV/AIDS: "let me live the way I want to live, until I can't".

    PubMed

    Selwyn, Peter A; Forstein, Marshall

    2003-08-13

    Recent advances in human immunodeficiency virus (HIV) therapy have significantly reduced HIV-related mortality in the developed world, but mortality rates have plateaued, and AIDS remains a leading cause of serious illness and death for young adults. The chronic nature of the HIV disease course and the increasing burden of cumulative HIV-related morbidity and treatment-related toxic effects pose new challenges to the care of patients over time. Uncertainties about prognosis and the promise and limitations of rapidly evolving therapies have made decision making about advance care planning and end-of-life issues more complex and elusive than when the disease course was more uniform, rapid, and predictable. The emerging biomedical paradigm of highly active antiretroviral therapy (HAART) as the cornerstone of treatment has helped to transform HIV into a manageable chronic disease, yet at the same time has resulted in a more narrow focus and a de facto separation between disease-specific "curative" and symptom-specific "palliative" care for patients with HIV/AIDS. As patients survive longer in the latter stages of progressive HIV disease, they may in fact have increasing need for comprehensive symptom management as well as wide-ranging need for psychosocial, family, and care planning support. In the HAART era, the false dichotomy of curative vs palliative care for patients with HIV/AIDS must be supplanted by a more integrated model to provide comprehensive care for patients with advanced HIV disease and their families. PMID:12915434

  10. Mitral annulus morphologic and functional analysis using real time tridimensional echocardiography in patients submitted to unsupported mitral valve repair

    PubMed Central

    Guedes, Marco Antnio Vieira; Pomerantzeff, Pablo Maria Alberto; Brando, Carlos Manuel de Almeida; Vieira, Marcelo Luiz Campos; Tarasoutchi, Flvio; Spinola, Pablo da Cunha; Jatene, Fbio Biscegli

    2015-01-01

    Introduction Mitral valve repair is the treatment of choice to correct mitral insufficiency, although the literature related to mitral valve annulus behavior after mitral repair without use of prosthetic rings is scarce. Objective To analyze mitral annulus morphology and function using real time tridimensional echocardiography in individuals submitted to mitral valve repair with Double Teflon technique. Methods Fourteen patients with mitral valve insufficiency secondary to mixomatous degeneration that were submitted to mitral valve repair with the Double Teflon technique were included. Thirteen patients were in FC III/IV. Patients were evaluated in preoperative period, immediate postoperative period, 6 months and 1 year after mitral repair. Statistical analysis was made by repeated measures ANOVA test and was considered statistically significant P<0.05. Results There were no deaths, reoperation due to valve dysfunction, thromboembolism or endocarditis during the study. Posterior mitral annulus demonstrated a significant reduction in immediate postoperative period (P<0.001), remaining stable during the study, and presents a mean of reduction of 25.8% comparing with preoperative period. There was a significant reduction in anteroposterior and mediolateral diameters in the immediate postoperative period (P<0.001), although there was a significant increase in mediolateral diameter between immediate postoperative period and 1 year. There was no difference in mitral internal area variation over the cardiac cycle during the study. Conclusion Segmentar annuloplasty reduced the posterior component of mitral annulus, which remained stable in a 1-year-period. The variation in mitral annulus area during cardiac cycle remained stable during the study. PMID:26313723

  11. Melt - Fluid Dichotomy vs. a Regime Involving Liquids Supercritical With Respect to the Endpoint of the Solidus and Geochemical Consequences for Subduction Zones (or: the end of the ''Melting the Slab'' - Myth)

    NASA Astrophysics Data System (ADS)

    Schmidt, M. W.; Kessel, R.

    2005-12-01

    At crustal pressures, phase relations in natural rock-H2O systems involve low density aqueous fluids (supercritical with respect to the endpoint of the H2O melt-gas phase) and/or high density hydrous melts. The wide miscibility gap between these two liquid phases leads to a dichotomy of mobile phases with quite distinct element solubilites and geochemical signatures. As pressure increases, the fluid-melt miscibility gap closes at ever lower temperatures, until the crest of the miscibility gap intersects the ''wet'' solidus at it's endpoint, leaving a single liquid, that has chemical and physical properties continuously evolving with temperature, and which is supercritical with respect to the endpoint of the solidus. These facts are well known and the principal necessary phase diagrams have been completed at latest with Ricci (1951). The question is then, at what conditions would the endpoint of the solidus be relevant for natural rock compositions. We have determined this endpoint by two different methods. In a potassium-enriched MORB, a greywacke, and a metapelite (Schmidt et al, 2004, EPSL) a discontinuous melting reaction where phengite disappears in favor of a quenchable hydrous melt exists to 5 GPa. Continuous dissolution of phengite in all three compositions is observed at 6 GPa, a quenchable K-bearing phase was then not formed. Secondly, in a K-free MORB, we measured the composition of the liquid phase from a diamond trap including H2O-contents (Kessel et al, 2005, EPSL), again observing classical melting at 5 GPa but a continuously evolving liquid composition at 6 GPa. The subsolidus assemblage consisted always of cpx+gar+coes±ky(+phengite in K2O bearing bulks), the main differences being omphacitic instead of jadeitic cpx and grossular enriched garnets in MORBs, and of course phase abundances. At 3-5 GPa, melting reactions and initial granitic melt compositions are similar in clastic metasediments and K-bearing MORB, a quartz poor greywacke would have the highest melt productivity. Locating the endpoint of the solidus between 5 and 6 GPa, 900-1000 °C indicates, that (i) at higher pressures, the dichotomy of fluid vs. melt ceases to exist in the oceanic crust, and (ii) that relatively small amounts of CaO, MgO and FeO (in the metapelite) shifts the solidus' endpoint to quite high pressures, i.e. from 1.0 and 1.5 GPa in the SiO2- and albite-H2O systems, respectively. The consequences of the solidus' endpoint were investigated by measuring trace element partitioning between cpx-gar-liquid, the latter either an aqueous fluid, hydrous melt, or supercritical liquid. Hydrous melts and supercritical liquids (the latter down to at least 200 °C below the hypothetical extension of the solidus) are almost undistinguishable in their trace element pattern, in particular, both have bulk Dsolid/liquidTh > Dsolid/liquidu, the mobility of Th and Be is even increased in the supercritical liquid (Kessel et al, 2005, Nature). Thus, recycling rates of these elements are not indicative of melting, and in the fast and steep circum-pacific subduction zones, they most likely testify for production of a mobile phase from the subducting crust in the supercritical liquid regime (beyond the endpoint of the solidus).

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

    SciTech Connect

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

    2009-11-01

    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.

  13. Antipsychotic medication and cognitive function in schizophrenia.

    PubMed

    Hori, Hiroaki; Noguchi, Hiroko; Hashimoto, Ryota; Nakabayashi, Tetsuo; Omori, Mayu; Takahashi, Sho; Tsukue, Ryotaro; Anami, Kimitaka; Hirabayashi, Naotsugu; Harada, Seiichi; Saitoh, Osamu; Iwase, Masao; Kajimoto, Osami; Takeda, Masatoshi; Okabe, Shigeo; Kunugi, Hiroshi

    2006-09-01

    Antipsychotic polypharmacy and excessive dosing still prevail worldwide in the treatment of schizophrenia, while their possible association with cognitive function has not well been examined. We examined whether the "non-standard" use of antipsychotics (defined as antipsychotic polypharmacy or dosage >1,000 mg/day of chlorpromazine equivalents) is associated with cognitive function. Furthermore, we compared cognitive function between patients taking only atypical antipsychotics and those taking only conventionals. Neurocognitive functions were assessed in 67 patients with chronic schizophrenia and 92 controls using the Wechsler Memory Scale-Revised (WMS-R), the Wechsler Adult Intelligence Scale-Revised (WAIS-R), the Wisconsin Card Sorting Test (WCST), and the Advanced Trail Making Test (ATMT). Patients showed markedly poorer performance than controls on all these tests. Patients on non-standard antipsychotic medication demonstrated poorer performance than those on standard medication on visual memory, delayed recall, performance IQ, and executive function. Patients taking atypical antipsychotics showed better performance than those taking conventionals on visual memory, delayed recall, and executive function. Clinical characteristics such as duration of medication, number of hospitalizations, and concomitant antiparkinsonian drugs were different between the treatment groups (both dichotomies of standard/non-standard and conventional/atypical). These results provide evidence for an association between antipsychotic medication and cognitive function. This association between antipsychotic medication and cognitive function may be due to differential illness severity (e.g., non-standard treatment for severely ill patients who have severe cognitive impairment). Alternatively, poorer cognitive function may be due in part to polypharmacy or excessive dosing. Further investigations are required to draw any conclusions. PMID:16793238

  14. The functional neuroanatomy of the human orbitofrontal cortex: evidence from neuroimaging and neuropsychology.

    PubMed

    Kringelbach, Morten L; Rolls, Edmund T

    2004-04-01

    The human orbitofrontal cortex is an important brain region for the processing of rewards and punishments, which is a prerequisite for the complex and flexible emotional and social behaviour which contributes to the evolutionary success of humans. Yet much remains to be discovered about the functions of this key brain region, and new evidence from functional neuroimaging and clinical neuropsychology is affording new insights into the different functions of the human orbitofrontal cortex. We review the neuroanatomical and neuropsychological literature on the human orbitofrontal cortex, and propose two distinct trends of neural activity based on a meta-analysis of neuroimaging studies. One is a mediolateral distinction, whereby medial orbitofrontal cortex activity is related to monitoring the reward value of many different reinforcers, whereas lateral orbitofrontal cortex activity is related to the evaluation of punishers which may lead to a change in ongoing behaviour. The second is a posterior-anterior distinction with more complex or abstract reinforcers (such as monetary gain and loss) represented more anteriorly in the orbitofrontal cortex than simpler reinforcers such as taste or pain. Finally, we propose new neuroimaging methods for obtaining further evidence on the localisation of function in the human orbitofrontal cortex. PMID:15157726

  15. Dynamic morphological changes in the skulls of mice mimicking human Apert syndrome resulting from gain-of-function mutation of FGFR2 (P253R).

    PubMed

    Du, Xiaolan; Weng, Tujun; Sun, Qidi; Su, Nan; Chen, Zhi; Qi, Huabing; Jin, Ming; Yin, Liangjun; He, Qifen; Chen, Lin

    2010-08-01

    Apert syndrome is caused mainly by gain-of-function mutations of fibroblast growth factor receptor 2. We have generated a mouse model (Fgfr2(+/P253R)) mimicking human Apert syndrome resulting from fibroblast growth factor receptor 2 Pro253Arg mutation using the knock-in approach. This mouse model in general has the characteristic skull morphology similar to that in humans with Apert syndrome. To characterize the detailed changes of form in the overall skull and its major anatomic structures, euclidean distance matrix analysis was used to quantitatively compare the form and growth difference between the skulls of mutants and their wild-type controls. There were substantial morphological differences between the skulls of mutants and their controls at 4 and 8 weeks of age (P < 0.01). The mutants showed shortened skull dimensions along the rostrocaudal axis, especially in their face. The width of the frontal bone and the distance between the two orbits were broadened mediolaterally. The neurocrania were significantly increased along the dorsoventral axis and slightly increased along the mediolateral axis, and also had anteriorly displayed opisthion along the rostrocaudal axis. Compared with wild-type, the mutant mandible had an anteriorly displaced coronoid process and mandibular condyle along the rostrocaudal axis. We further found that there was catch-up growth in the nasal bone, maxilla, zygomatic bone and some regions of the mandible of the mutant skulls during the 4-8-week interval. The above-mentioned findings further validate the Fgfr2(+/P253R) mouse strain as a good model for human Apert syndrome. The changes in form characterized in this study will help to elucidate the mechanisms through which the Pro253Arg mutation in fibroblast growth factor receptor 2 affects craniofacial development and causes Apert syndrome. PMID:20557404

  16. Dynamic morphological changes in the skulls of mice mimicking human Apert syndrome resulting from gain-of-function mutation of FGFR2 (P253R)

    PubMed Central

    Du, Xiaolan; Weng, Tujun; Sun, Qidi; Su, Nan; Chen, Zhi; Qi, Huabing; Jin, Ming; Yin, Liangjun; He, Qifen; Chen, Lin

    2010-01-01

    Apert syndrome is caused mainly by gain-of-function mutations of fibroblast growth factor receptor 2. We have generated a mouse model (Fgfr2+/P253R) mimicking human Apert syndrome resulting from fibroblast growth factor receptor 2 Pro253Arg mutation using the knock-in approach. This mouse model in general has the characteristic skull morphology similar to that in humans with Apert syndrome. To characterize the detailed changes of form in the overall skull and its major anatomic structures, euclidean distance matrix analysis was used to quantitatively compare the form and growth difference between the skulls of mutants and their wild-type controls. There were substantial morphological differences between the skulls of mutants and their controls at 4 and 8 weeks of age (P<0.01). The mutants showed shortened skull dimensions along the rostrocaudal axis, especially in their face. The width of the frontal bone and the distance between the two orbits were broadened mediolaterally. The neurocrania were significantly increased along the dorsoventral axis and slightly increased along the mediolateral axis, and also had anteriorly displayed opisthion along the rostrocaudal axis. Compared with wild-type, the mutant mandible had an anteriorly displaced coronoid process and mandibular condyle along the rostrocaudal axis. We further found that there was catch-up growth in the nasal bone, maxilla, zygomatic bone and some regions of the mandible of the mutant skulls during the 4–8-week interval. The above-mentioned findings further validate the Fgfr2+/P253R mouse strain as a good model for human Apert syndrome. The changes in form characterized in this study will help to elucidate the mechanisms through which the Pro253Arg mutation in fibroblast growth factor receptor 2 affects craniofacial development and causes Apert syndrome. PMID:20557404

  17. Directed functional connectivity matures with motor learning in a cortical pattern generator.

    PubMed

    Day, Nancy F; Terleski, Kyle L; Nykamp, Duane Q; Nick, Teresa A

    2013-02-01

    Sequential motor skills may be encoded by feedforward networks that consist of groups of neurons that fire in sequence (Abeles 1991; Long et al. 2010). However, there has been no evidence of an anatomic map of activation sequence in motor control circuits, which would be potentially detectable as directed functional connectivity of coactive neuron groups. The proposed pattern generator for birdsong, the HVC (Long and Fee 2008; Vu et al. 1994), contains axons that are preferentially oriented in the rostrocaudal axis (Nottebohm et al. 1982; Stauffer et al. 2012). We used four-tetrode recordings to assess the activity of ensembles of single neurons along the rostrocaudal HVC axis in anesthetized zebra finches. We found an axial, polarized neural network in which sequential activity is directionally organized along the rostrocaudal axis in adult males, who produce a stereotyped song. Principal neurons fired in rostrocaudal order and with interneurons that were rostral to them, suggesting that groups of excitatory neurons fire at the leading edge of travelling waves of inhibition. Consistent with the synchronization of neurons by caudally travelling waves of inhibition, the activity of interneurons was more coherent in the orthogonal mediolateral axis than in the rostrocaudal axis. If directed functional connectivity within the HVC is important for stereotyped, learned song, then it may be lacking in juveniles, which sing a highly variable song. Indeed, we found little evidence for network directionality in juveniles. These data indicate that a functionally directed network within the HVC matures during sensorimotor learning and may underlie vocal patterning. PMID:23175804

  18. Returners and explorers dichotomy in human mobility

    NASA Astrophysics Data System (ADS)

    Pappalardo, Luca; Simini, Filippo; Rinzivillo, Salvatore; Pedreschi, Dino; Giannotti, Fosca; Barabási, Albert-László

    2015-09-01

    The availability of massive digital traces of human whereabouts has offered a series of novel insights on the quantitative patterns characterizing human mobility. In particular, numerous recent studies have lead to an unexpected consensus: the considerable variability in the characteristic travelled distance of individuals coexists with a high degree of predictability of their future locations. Here we shed light on this surprising coexistence by systematically investigating the impact of recurrent mobility on the characteristic distance travelled by individuals. Using both mobile phone and GPS data, we discover the existence of two distinct classes of individuals: returners and explorers. As existing models of human mobility cannot explain the existence of these two classes, we develop more realistic models able to capture the empirical findings. Finally, we show that returners and explorers play a distinct quantifiable role in spreading phenomena and that a correlation exists between their mobility patterns and social interactions.

  19. Dichotomies in Teaching, Application, and Ethics

    ERIC Educational Resources Information Center

    Heames, Joyce T.; Service, Robert W.

    2003-01-01

    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…

  20. Tutoring and Teaching: Continuum, Dichotomy, or Dialectic?

    ERIC Educational Resources Information Center

    Raines, Helon H.

    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…

  1. [On the social production of sexual dichotomy].

    PubMed

    Schildberger, B

    2011-02-01

    Notwithstanding scientific evidence about the development of sexuality and possible sexual variations, the social dogma of the duality of the sexes hardly tolerates deviations from the defined norms of female and male. The diagnosis of intersexuality is mostly considered as a treatable disease with the chance of eventual sexual adaptation; transsexuality in any form is placed at the social periphery as an individual symptomatology. This review discusses the presence, actuality and sense of coherence of heteronormativity and outlines the consequences of an attributed sexuality. PMID:21344344

  2. Returners and explorers dichotomy in human mobility

    PubMed Central

    Pappalardo, Luca; Simini, Filippo; Rinzivillo, Salvatore; Pedreschi, Dino; Giannotti, Fosca; Barabási, Albert-László

    2015-01-01

    The availability of massive digital traces of human whereabouts has offered a series of novel insights on the quantitative patterns characterizing human mobility. In particular, numerous recent studies have lead to an unexpected consensus: the considerable variability in the characteristic travelled distance of individuals coexists with a high degree of predictability of their future locations. Here we shed light on this surprising coexistence by systematically investigating the impact of recurrent mobility on the characteristic distance travelled by individuals. Using both mobile phone and GPS data, we discover the existence of two distinct classes of individuals: returners and explorers. As existing models of human mobility cannot explain the existence of these two classes, we develop more realistic models able to capture the empirical findings. Finally, we show that returners and explorers play a distinct quantifiable role in spreading phenomena and that a correlation exists between their mobility patterns and social interactions. PMID:26349016

  3. Chimaeric sounds reveal dichotomies in auditory perception

    NASA Astrophysics Data System (ADS)

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

    2002-03-01

    By Fourier's theorem, 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 Hilbert, is to factor a signal into the product of a slowly varying envelope and a rapidly varying fine time structure. Neurons in the auditory brainstem 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 cortex.

  4. ODL and Traditional Universities: Dichotomy or Convergence?

    ERIC Educational Resources Information Center

    Curran, Chris

    1997-01-01

    Examines the evolution of open distance learning (ODL) in the United Kingdom, particularly in relation to traditional universities and to recent developments in telematics. Argues that a major test of the new technologies in distance education will be their capacity to support real academic communities, allowing the university to maintain the best…

  5. Effects of virtual reality programs on balance in functional ankle instability

    PubMed Central

    Kim, Ki-Jong; Heo, Myoung

    2015-01-01

    [Purpose] The aim of present study was to identify the impact that recent virtual reality training programs used in a variety of fields have had on the ankle’s static and dynamic senses of balance among subjects with functional ankle instability. [Subjects and Methods] This study randomly divided research subjects into two groups, a strengthening exercise group (Group I) and a balance exercise group (Group II), with each group consisting of 10 people. A virtual reality program was performed three times a week for four weeks. Exercises from the Nintendo Wii Fit Plus program were applied to each group for twenty minutes along with ten minutes of warming up and wrap-up exercises. [Results] Group II showed a significant decrease of post-intervention static and dynamic balance overall in the anterior-posterior, and mediolateral directions, compared with the pre-intervention test results. In comparison of post-intervention static and dynamic balance between Group I and Group II, a significant decrease was observed overall. [Conclusion] Virtual reality programs improved the static balance and dynamic balance of subjects with functional ankle instability. Virtual reality programs can be used more safely and efficiently if they are implemented under appropriate monitoring by a physiotherapist. PMID:26644652

  6. Evaluation of functional deficits and falls risk in the elderly--methods for preventing falls.

    PubMed

    Narayanan, Michael R; Scalzi, Maria Elena; Redmond, Stephen J; Lord, Steven R; Celler, Branko G; Lovell, Nigel H

    2009-01-01

    Falls in the elderly have a profound impact on their quality of life through injury, increased fear of falling, reduced confidence to perform daily tasks and loss of independence. Falls come at a substantial economic cost. Tools to quantify falls risk and evaluate functional deficits allow interventions to be targeted to those at increased risk of falling and tailored to correct deficits with the aim of reducing falls rate and reducing ones risk of falling. We describe a system to evaluate falls risk and functional deficits in the elderly. The system is based on the evaluation of performance in a simple set of controlled movements known as the directed routine (DR). We present preliminary results of the DR in a cohort of 68 subjects using features extracted from the DR. Linear least-squares models were trained to estimate falls risk, knee-extension strength, proprioception, mediolateral body sway, anteroposterior body sway and contrast sensitivity. The model estimates provided good to fair correlations with (r=0.76 p<0.001), (r=0.65 p<0.001), (r=0.35 p<0.01), (r=0.53 p<0.001), (r=0.48 p<0.001) and (r=0.37 p<0.01) respectively. PMID:19964895

  7. Effects of virtual reality programs on balance in functional ankle instability.

    PubMed

    Kim, Ki-Jong; Heo, Myoung

    2015-10-01

    [Purpose] The aim of present study was to identify the impact that recent virtual reality training programs used in a variety of fields have had on the ankle's static and dynamic senses of balance among subjects with functional ankle instability. [Subjects and Methods] This study randomly divided research subjects into two groups, a strengthening exercise group (Group I) and a balance exercise group (Group II), with each group consisting of 10 people. A virtual reality program was performed three times a week for four weeks. Exercises from the Nintendo Wii Fit Plus program were applied to each group for twenty minutes along with ten minutes of warming up and wrap-up exercises. [Results] Group II showed a significant decrease of post-intervention static and dynamic balance overall in the anterior-posterior, and mediolateral directions, compared with the pre-intervention test results. In comparison of post-intervention static and dynamic balance between Group I and Group II, a significant decrease was observed overall. [Conclusion] Virtual reality programs improved the static balance and dynamic balance of subjects with functional ankle instability. Virtual reality programs can be used more safely and efficiently if they are implemented under appropriate monitoring by a physiotherapist. PMID:26644652

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

    PubMed Central

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

    2014-01-01

    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

  9. Vascular smooth muscle phenotypic diversity and function

    PubMed Central

    2010-01-01

    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

  10. Wave-function functionals

    SciTech Connect

    Pan Xiaoyin; Slamet, Marlina; Sahni, Viraht

    2010-04-15

    We extend our prior work on the construction of variational wave functions {psi} that are functionals of functions {chi}:{psi}={psi}[{chi}] rather than simply being functions. In this manner, the space of variations is expanded over those of traditional variational wave functions. In this article we perform the constrained search over the functions {chi} chosen such that the functional {psi}[{chi}] satisfies simultaneously the constraints of normalization and the exact expectation value of an arbitrary single- or two-particle Hermitian operator, while also leading to a rigorous upper bound to the energy. As such the wave function functional is accurate not only in the region of space in which the principal contributions to the energy arise but also in the other region of the space represented by the Hermitian operator. To demonstrate the efficacy of these ideas, we apply such a constrained search to the ground state of the negative ion of atomic hydrogen H{sup -}, the helium atom He, and its positive ions Li{sup +} and Be{sup 2+}. The operators W whose expectations are obtained exactly are the sum of the 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}), W=-(1/2){Sigma}{sub i{nabla}i}{sup 2}, and the two-particle operators W={Sigma}{sub n}u{sup n},n=-2,-1,1,2, where u=|r{sub i}-r{sub j}|. Comparisons with the method of Lagrangian multipliers and of other constructions of wave-function functionals are made. Finally, we present further insights into the construction of wave-function functionals by studying a previously proposed construction of functionals {psi}[{chi}] that lead to the exact expectation of arbitrary Hermitian operators. We discover that analogous to the solutions of the Schroedinger equation, there exist {psi}[{chi}] that are unphysical in that they lead to singular values for the expectations. We also explain the origin of the singularity.

  11. Morphology and behaviour: functional links in development and evolution

    PubMed Central

    Bertossa, Rinaldo C.

    2011-01-01

    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

  12. Morphological and functional changes in the vertebral column with increasing aquatic adaptation in crocodylomorphs.

    PubMed

    Molnar, Julia L; Pierce, Stephanie E; Bhullar, Bhart-Anjan S; Turner, Alan H; Hutchinson, John R

    2015-11-01

    The lineage leading to modern Crocodylia has undergone dramatic evolutionary changes in morphology, ecology and locomotion over the past 200+ Myr. These functional innovations may be explained in part by morphological changes in the axial skeleton, which is an integral part of the vertebrate locomotor system. Our objective was to estimate changes in osteological range of motion (RoM) and intervertebral joint stiffness of thoracic and lumbar vertebrae with increasing aquatic adaptation in crocodylomorphs. Using three-dimensional virtual models and morphometrics, we compared the modern crocodile Crocodylus to five extinct crocodylomorphs: Terrestrisuchus, Protosuchus, Pelagosaurus, Steneosaurus and Metriorhynchus, which span the spectrum from terrestrial to fully aquatic. In Crocodylus, we also experimentally measured changes in trunk flexibility with sequential removal of osteoderms and soft tissues. Our results for the more aquatic species matched our predictions fairly well, but those for the more terrestrial early crocodylomorphs did not. A likely explanation for this lack of correspondence is the influence of other axial structures, particularly the rigid series of dorsal osteoderms in early crocodylomorphs. The most important structures for determining RoM and stiffness of the trunk in Crocodylus were different in dorsoventral versus mediolateral bending, suggesting that changes in osteoderm and rib morphology over crocodylomorph evolution would have affected movements in some directions more than others. PMID:26716001

  13. Double-leg stance and dynamic balance in individuals with functional ankle instability.

    PubMed

    Groters, S; Groen, B E; van Cingel, R; Duysens, J

    2013-09-01

    To investigate whether double-leg stance could reveal balance deficits in subjects with functional ankle instability (FAI) and whether such an assessment of static balance would be correlated with measures of dynamic instability, 16 individuals with FAI and 16 healthy controls participated in this study. Static postural control was tested using double-leg stance (either with the eyes open (EO) or closed (EC)) on a dual-plate force platform. Dynamic balance was evaluated using the Multiple Hop Test (MHT) and a weight-shifting task. FAI subjects were significantly less stable in the anteroposterior direction during double-leg stance (as assessed by velocity of centre of pressure, VCP), both for the EO and EC condition. In the mediolateral direction the VCP values were also higher in FAI, but significance was only found for the EC condition (p=.02). FAI subjects made significantly more balance errors compared to healthy controls (p<.001) on both the affected and less affected leg during MHT. There were no significant differences between FAI and healthy subjects during the weight-shifting task. No relationship was found between double-leg stance and MHT measures (all correlations (rs) less than .30). This study suggests that static postural control during double-leg stance is impaired in FAI subjects. Although dynamic balance during MHT is also affected, no significant relationship was found between static and dynamic measurements, which indicate that they are most probably related to different aspects of postural control. PMID:23810093

  14. Morphological and functional changes in the vertebral column with increasing aquatic adaptation in crocodylomorphs

    PubMed Central

    Molnar, Julia L.; Pierce, Stephanie E.; Bhullar, Bhart-Anjan S.; Turner, Alan H.; Hutchinson, John R.

    2015-01-01

    The lineage leading to modern Crocodylia has undergone dramatic evolutionary changes in morphology, ecology and locomotion over the past 200+ Myr. These functional innovations may be explained in part by morphological changes in the axial skeleton, which is an integral part of the vertebrate locomotor system. Our objective was to estimate changes in osteological range of motion (RoM) and intervertebral joint stiffness of thoracic and lumbar vertebrae with increasing aquatic adaptation in crocodylomorphs. Using three-dimensional virtual models and morphometrics, we compared the modern crocodile Crocodylus to five extinct crocodylomorphs: Terrestrisuchus, Protosuchus, Pelagosaurus, Steneosaurus and Metriorhynchus, which span the spectrum from terrestrial to fully aquatic. In Crocodylus, we also experimentally measured changes in trunk flexibility with sequential removal of osteoderms and soft tissues. Our results for the more aquatic species matched our predictions fairly well, but those for the more terrestrial early crocodylomorphs did not. A likely explanation for this lack of correspondence is the influence of other axial structures, particularly the rigid series of dorsal osteoderms in early crocodylomorphs. The most important structures for determining RoM and stiffness of the trunk in Crocodylus were different in dorsoventral versus mediolateral bending, suggesting that changes in osteoderm and rib morphology over crocodylomorph evolution would have affected movements in some directions more than others. PMID:26716001

  15. Computerized tomography (CT) is just as accurate as ventriculography for functional stereotactic thalamotomy.

    PubMed

    Tasker, R R; Dostrovsky, J O; Dolan, E J

    1991-01-01

    Eighty-three consecutive functional stereotactic procedures (56 thalamotomies, 1 medial thalamotomy, and 26 chronic brain stimulatory electrode introductions) were done using CT to identify the three-dimensional coordinates of anterior and posterior commissures. The three-dimensional locations of the tactile relay in ventrobasal complex for manual digits were then determined as the first step in physiological corroboration of target site using single-cell recordings and microstimulation. The measured location of this structure was then compared with that predicted by the Schaltenbrand and Bailey atlas. There was no discrepancy in the mediolateral plane in 62.7%, in the dorsoventral plane in 63.9%, and in the anteroposterior plane in 44.6% of the cases. Over 2 mm deviation occurred in 10.8, 12.0, and 19.2% of the cases in these three planes, respectively. This precision of localization is better than that reported with ventriculography. Many of the larger discrepancies occurred in patients who had suffered from stroke, multiple sclerosis, severe head injury, or after craniotomy. PMID:1842974

  16. Diagnosis and management of functional symptoms in inflammatory bowel disease in remission

    PubMed Central

    Teruel, Carlos; Garrido, Elena; Mesonero, Francisco

    2016-01-01

    Inflammatory bowel disease (IBD) patients in remission may suffer from gastrointestinal symptoms that resemble irritable bowel syndrome (IBS). Knowledge on this issue has increased considerably in the last decade, and it is our intention to review and summarize it in the present work. We describe a problematic that comprises physiopathological uncertainties, diagnostic difficulties, as IBS-like symptoms are very similar to those produced by an inflammatory flare, and the necessity of appropriate management of these patients, who, although in remission, have impaired quality of life. Ultimately, from almost a philosophical point of view, the presence of IBS-like symptoms in IBD patients in remission supposes a challenge to the traditional functional-organic dichotomy, suggesting the need for a change of paradigm. PMID:26855814

  17. Diagnosis and management of functional symptoms in inflammatory bowel disease in remission.

    PubMed

    Teruel, Carlos; Garrido, Elena; Mesonero, Francisco

    2016-02-01

    Inflammatory bowel disease (IBD) patients in remission may suffer from gastrointestinal symptoms that resemble irritable bowel syndrome (IBS). Knowledge on this issue has increased considerably in the last decade, and it is our intention to review and summarize it in the present work. We describe a problematic that comprises physiopathological uncertainties, diagnostic difficulties, as IBS-like symptoms are very similar to those produced by an inflammatory flare, and the necessity of appropriate management of these patients, who, although in remission, have impaired quality of life. Ultimately, from almost a philosophical point of view, the presence of IBS-like symptoms in IBD patients in remission supposes a challenge to the traditional functional-organic dichotomy, suggesting the need for a change of paradigm. PMID:26855814

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

    PubMed

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

    2014-08-01

    [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

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

    PubMed Central

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

    2014-01-01

    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

  20. Using Low Levels of Stochastic Vestibular Stimulation to Improve Balance Function

    PubMed Central

    Goel, Rahul; Kofman, Igor; Jeevarajan, Jerome; De Dios, Yiri; Cohen, Helen S.; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.

    2015-01-01

    Low-level stochastic vestibular stimulation (SVS) has been associated with improved postural responses in the medio-lateral (ML) direction, but its effect in improving balance function in both the ML and anterior-posterior (AP) directions has not been studied. In this series of studies, the efficacy of applying low amplitude SVS in 0–30 Hz range between the mastoids in the ML direction on improving cross-planar balance function was investigated. Forty-five (45) subjects stood on a compliant surface with their eyes closed and were instructed to maintain a stable upright stance. Measures of stability of the head, trunk, and whole body were quantified in ML, AP and combined APML directions. Results show that binaural bipolar SVS given in the ML direction significantly improved balance performance with the peak of optimal stimulus amplitude predominantly in the range of 100–500 μA for all the three directions, exhibiting stochastic resonance (SR) phenomenon. Objective perceptual and body motion thresholds as estimates of internal noise while subjects sat on a chair with their eyes closed and were given 1 Hz bipolar binaural sinusoidal electrical stimuli were also measured. In general, there was no significant difference between estimates of perceptual and body motion thresholds. The average optimal SVS amplitude that improved balance performance (peak SVS amplitude normalized to perceptual threshold) was estimated to be 46% in ML, 53% in AP, and 50% in APML directions. A miniature patch-type SVS device may be useful to improve balance function in people with disabilities due to aging, Parkinson’s disease or in astronauts returning from long-duration space flight. PMID:26295807

  1. Approximating Functions with Exponential Functions

    ERIC Educational Resources Information Center

    Gordon, Sheldon P.

    2005-01-01

    The possibility of approximating a function with a linear combination of exponential functions of the form e[superscript x], e[superscript 2x], ... is considered as a parallel development to the notion of Taylor polynomials which approximate a function with a linear combination of power function terms. The sinusoidal functions sin "x" and cos "x"…

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

    NASA Technical Reports Server (NTRS)

    Simon, M.; Mileant, A.

    1986-01-01

    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.

  3. Functional aspects of metatarsal head shape in humans, apes, and Old World monkeys.

    PubMed

    Fernández, Peter J; Almécija, Sergio; Patel, Biren A; Orr, Caley M; Tocheri, Matthew W; Jungers, William L

    2015-09-01

    Modern human metatarsal heads are typically described as "dorsally domed," mediolaterally wide, and dorsally flat. Despite the apparent functional importance of these features in forefoot stability during bipedalism, the distinctiveness of this morphology has not been quantitatively evaluated within a broad comparative framework. In order to use these features to reconstruct fossil hominin locomotor behaviors with any confidence, their connection to human bipedalism should be validated through a comparative analysis of other primates with different locomotor behaviors and foot postures, including species with biomechanical demands potentially similar to those of bipedalism (e.g., terrestrial digitigrady). This study explores shape variation in the distal metatarsus among humans and other extant catarrhines using three-dimensional geometric morphometrics (3 DGM). Shape differences among species in metatarsal head morphology are well captured by the first two principal components of Procrustes shape coordinates, and these two components summarize most of the variance related to "dorsal doming" and "dorsal expansion." Multivariate statistical tests reveal significant differences among clades in overall shape, and humans are reliably distinguishable from other species by aspects of shape related to a greater degree of dorsal doming. Within quadrupeds, terrestrial species also trend toward more domed metatarsal heads, but not to the extent seen in humans. Certain aspects of distal metatarsus shape are likely related to habitual dorsiflexion of the metatarsophalangeal joints, but the total morphological pattern seen in humans is distinct. These comparative results indicate that this geometric morphometric approach is useful to characterize the complexity of metatarsal head morphology and will help clarify its relationship with function in fossil primates, including early hominins. PMID:26276534

  4. A new approach to measure functional stability of the knee based on changes in knee axis orientation.

    PubMed

    Grip, H; Häger, C

    2013-03-15

    There is a lack of measures that quantify functional knee stability, which is of particular relevance in knee rehabilitation. Therefore, the aim of this study was to investigate the usefulness of knee finite helical axis (FHA) variables in 33 healthy subjects during two different functional tasks; One leg side hop (SH) and Two Leg Squat (TLS), and to investigate correlations of these variables with laxity. Laxity was assessed with a KT-1000 arthrometer and the Beighton Hypermobility Score. Movements were registered with an optical motion capture system. Knee rotation and translation were defined by a six degree of freedom segment model. FHA was calculated for finite steps of 20° knee flexion, based on error simulations. We computed the FHA inclination, the translation along FHA and an FHA Direction Index quantifying directional changes. All variables were repeatable (average ICCs ~0.97 during TLS and ~0.83 during SH). The lower functional knee stability in SH was reflected by a significantly higher FHA Direction Index and a larger medio-lateral FHA inclination compared to those in TLS. The superior-inferior inclination was smaller during Landing in SH compared to Take-Off and TLS. Translation along FHA was generally small as expected in healthy subjects. Beighton Hypermobility Score and KT-1000 values had weak but significant correlations with FHA Direction Index and FHA translation, which show that laxity influences the functional knee stability. We conclude that FHA measures were sensitive enough to discriminate between SH and TLS. The next step is to investigate the usability of these measures in subjects with knee injury. PMID:23374277

  5. Orbit Functions

    NASA Astrophysics Data System (ADS)

    Klimyk, Anatoliy; Patera, Jiri

    2006-01-01

    In the paper, properties of orbit functions are reviewed and further developed. Orbit functions on the Euclidean space En are symmetrized exponential functions. The symmetrization is fulfilled by a Weyl group corresponding to a Coxeter-Dynkin diagram. Properties of such functions will be described. An orbit function is the contribution to an irreducible character of a compact semisimple Lie group G of rank n from one of its Weyl group orbits. It is shown that values of orbit functions are repeated on copies of the fundamental domain F of the affine Weyl group (determined by the initial Weyl group) in the entire Euclidean space En. Orbit functions are solutions of the corresponding Laplace equation in En, satisfying the Neumann condition on the boundary of F. Orbit functions determine a symmetrized Fourier transform and a transform on a finite set of points.

  6. Highly specific role of hypocretin (orexin) neurons: differential activation as a function of diurnal phase, operant reinforcement versus operant avoidance and light level.

    PubMed

    McGregor, Ronald; Wu, Ming-Fung; Barber, Grace; Ramanathan, Lalini; Siegel, Jerome M

    2011-10-26

    Hypocretin (Hcrt) cell loss is responsible for narcolepsy, but Hcrt's role in normal behavior is unclear. We found that Hcrt knock-out mice were unable to work for food or water reward during the light phase. However, they were unimpaired relative to wild-type (WT) mice when working for reward during the dark phase or when working to avoid shock in the light or dark phase. In WT mice, expression of Fos in Hcrt neurons occurs only in the light phase when working for positive reinforcement. Expression was seen throughout the mediolateral extent of the Hcrt field. Fos was not expressed when expected or unexpected unearned rewards were presented, when working to avoid negative reinforcement, or when given or expecting shock, even though these conditions elicit maximal electroencephalogram (EEG) arousal. Fos was not expressed in the light phase when light was removed. This may explain the lack of light-induced arousal in narcoleptics and its presence in normal individuals. This is the first demonstration of such specificity of arousal system function and has implications for understanding the motivational and circadian consequences of arousal system dysfunction. The current results also indicate that comparable and complementary specificities must exist in other arousal systems. PMID:22031892

  7. Highly specific role of hypocretin (orexin) neurons: differential activation as a function of diurnal phase, operant reinforcement vs. operant avoidance and light level

    PubMed Central

    McGregor, Ronald; Wu, Ming-Fung; Barber, Grace; Ramanathan, Lalini; Siegel, Jerome M.

    2011-01-01

    Hypocretin (Hcrt) cell loss is responsible for narcolepsy, but Hcrt's role in normal behavior is unclear. We found that Hcrt KO mice were unable to work for food or water reward during the light phase. However, they were unimpaired relative to wild type (WT) mice when working for reward during the dark phase or when working to avoid shock in the light or dark phases. In WT, expression of Fos in Hcrt neurons occurs only in the light phase when working for positive reinforcement. Expression was seen throughout the medio-lateral extent of the Hcrt field. Fos was not expressed when expected or unexpected, unearned rewards were presented, when working to avoid negative reinforcement, or when given or expecting shock, even though these conditions elicit maximal electroencephalographic (EEG) arousal. Fos was not expressed in the light phase when light was removed. This may explain the lack of light induced arousal in narcoleptics and its presence in normal individuals. This is the first demonstration of such specificity of arousal system function and has implications for understanding the motivational and circadian consequences of arousal system dysfunction. The current results also indicate that comparable and complementary specificities must exist in other “arousal” systems. PMID:22031892

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

    PubMed

    Mikolajczyk, Edyta; Jankowicz-Szymanska, Agnieszka

    2015-03-01

    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

  9. The buccinator during mastication: a functional and anatomical evaluation in minipigs

    PubMed Central

    Dutra, Eliane H.; Caria, Paulo H. F.; Rafferty, Katherine L.; Herring, Susan W.

    2010-01-01

    Objective The buccinator muscle forms the lateral wall of the oral cavity. It is presumed to aid mastication by maintaining bolus position. Such a function would involve thickening the cheek, possibly compressing the alveolar bone and contributing to malocclusions. However, neither buccinator deformation nor its effect on pressure has been demonstrated. Our objective was to evaluate buccinator EMG during feeding, its changes in length and thickness, and the pressure exerted on its alveolar attachment, using miniature pigs as an animal model. Methods EMG of the buccinator and other oral muscles was recorded with fine-wire electrodes. Anteroposterior length and mediolateral thickness of the buccinator were evaluated with implanted sonomicrometry crystals, and pressure was measured by flat transducers placed beneath the mandibular origin of the buccinator. Recordings were made during feeding and muscle stimulation. Tissues were collected postmortem for histology. Results During mastication, buccinator EMG showed regular peaks that preceded those of the jaw closers. Pattern differences clearly distinguished working and balancing sides. The buccinator shortened and thickened when it contracted. Positive pressures were observed at the mandibular attachment of the buccinator, increasing when the muscle was active. Histological evaluation showed a complex interweaving of fibers closely associated with salivary tissue. Conclusions Buccinator contraction does thicken the cheek, and during mastication this activity takes place just as the closing stroke begins. In addition to controlling the bolus, there may be an effect on salivation. Despite the fact that the muscle pulls on its attachment, the local mechanical environment at the alveolar bone is one of positive pressure. PMID:20621287

  10. Lower-limb amputee ankle and hip kinetic response to an imposed error in mediolateral foot placement.

    PubMed

    Segal, Ava D; Shofer, Jane B; Klute, Glenn K

    2015-11-26

    Maintaining balance while walking is challenging for lower limb amputees. The effect of prosthetic foot stiffness on recovery kinetics from an error in foot placement may inform prescription practice and lead to new interventions designed to improve balance. Ten unilateral transtibial amputees were fit with two prosthetic feet with different stiffness properties in random order. After a 3-week acclimation period, they returned to the lab for testing before switching feet. Twelve non-amputees also participated in a single data collection. While walking on an instrumented treadmill, we imposed a repeatable, unexpected medial or lateral disturbance in foot placement by releasing a burst of air at the ankle just before heel strike. Three-dimensional motion capture, ground reaction force and center of pressure (COP) data were collected for two steps prior, the disturbed step and three steps after the disturbance. During undisturbed walking, coronal ankle impulse was lower by 42% for amputees wearing a stiff compared to a compliant foot (p=0.017); however, across steps, both prosthetic recovery patterns were similar compared to the sound limb and non-amputees. Peak coronal hip moment was 15-20% lower for both foot types during undisturbed walking (p<0.001), with less change in response to the medial disturbance (p<0.001) compared to the sound limb and non-amputees. Amputee prosthetic COP excursion was unaffected by the disturbance (2.4% change) compared to the sound limb (59% change; p<0.001) and non-amputees (55% change; p<0.001). These findings imply that a prosthetic foot-ankle system able to contribute to ankle kinetics may improve walking balance among amputees. PMID:26475221

  11. 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...

  12. Synaptic function.

    PubMed Central

    Richmond, Janet

    2005-01-01

    C. elegans has emerged as a powerful genetic model organism in which to study synaptic function. Most synaptic proteins in the C. elegans genome are highly conserved and mutants can be readily generated by forward and reverse genetics. Most C. elegans synaptic protein mutants are viable affording an opportunity to study the functional consequences in vivo. Recent advances in electrophysiological approaches permit functional analysis of mutant synapses in situ. This has contributed to an already powerful arsenal of techniques available to study synaptic function in C. elegans. This review highlights C. elegans mutants affecting specific stages of the synaptic vesicle cycle, with emphasis on studies conducted at the neuromuscular junction. PMID:18050398

  13. Functional metadata

    NASA Astrophysics Data System (ADS)

    Rogge, Boris; Van de Walle, Rik; Lemahieu, Ignace L.

    2001-07-01

    The current state of the art in content description (MPEG-7) does not provide a rich set of tools to create functional metadata (metadata that contains not only the description of the content but also a set of methods that can be used to interpret, change or analyze the content). This paper presents a framework of which the primary goal is the integration of functional metadata into the existing standards. Whenever it is not only important what is in the multimedia content, but also what is happening with the information in the content, functional metadata can be used to describe this. Some examples are: news tickers, sport results, online auctions. In order to extend content description schemes with extra functionality, MPEG-7 based descriptors are defined to allow the content creator to add his own properties and methods to the multimedia data, thus making the multimedia data self describing and manipulatable. These descriptors incorporate concepts from object technology such as objects, interfaces and events. Descriptors allow the content creator to add properties to these objects and interfaces, methods can be defined using a descriptor and activated using events. The generic use of these properties and methods are the core of the functional metadata framework. A complete set of MPEG-7 based descriptors and descriptor schemes is presented, enabling the content creator to add functional metadata to the multimedia data. An implementation of the proposed framework has been created proving the principles of functional metadata. This paper presents a method for adding extra functionality to metadata and hence to multimedia data. It is shown that doing so preserves existing content description methods and that the functional metadata extends the possibilities of the use of content description.

  14. Glycosphingolipid Functions

    PubMed Central

    Lingwood, Clifford A.

    2011-01-01

    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

  15. 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)

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

    2011-03-01

    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!!!].

  16. Transfer functions

    NASA Technical Reports Server (NTRS)

    Taback, I.

    1979-01-01

    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.

  17. 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)

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

    2013-03-01

    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(G...P) first use of the ``square-of-opposition'' in physics since Plato and Aristote!!!

  18. Elementary Functions

    Energy Science and Technology Software Center (ESTSC)

    1986-05-01

    The ALTERNATIVE LIBRARY is a library of elementary functions prepared for use with the standard FORTRAN compiler under 4.2 BSD UNIX as an alternative to the standard system library. The library offers improved accuracy as well as additional capabilities. It includes routines ASIN, ACOS, COSH, EXP, LOG, LOG10, POW, SIN, COS, SINH, TAN, and TANH. These alternative routines have slightly modified domains and slightly different responses to invalid arguments. Four routines, not part of themore » standard library, are provided: ADX(X,N), a double-precision function that returns the double-precision argument X scaled by 2 raised to the Nth power; INTXP(X), an integer function that returns as a signed integer the exponent of the double-precision argument X; SETXP(X,N), a double-precision function that returns the double-precision argument X with its exponent replaced by N; and DCOTAN(X), a double-precision function that returns the cotangent of the double-precision argument X, where X is given in radians.« less

  19. Functional diarrhea.

    PubMed

    Tack, Jan

    2012-09-01

    Chronic diarrhea is a frequent and challenging problem in clinical medicine. In a considerable subgroup of these, no underlying cause is identified and this is referred to as functional diarrhea. A consensus definition for functional diarrhea is based on loose stool consistency and chronicity and absence of coexisting irritable bowel syndrome. Underlying pathophysiology includes rapid intestinal transit, which may be worsened by stress or be triggered by a preceding infectious gastroenteritis. Diagnostic work-up aims at exclusion of underlying organic disease. Treatment starts with dietary adjustments, aiming at decreasing nutrients that enhance transit and stool and at identifying precipitating food items. PMID:22917168

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

    PubMed Central

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

    2013-01-01

    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

  1. Turning semicircular canal function on its head: dinosaurs and a novel vestibular analysis.

    PubMed

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

    2013-01-01

    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

  2. The evolutionary continuum of limb function from early theropods to birds

    NASA Astrophysics Data System (ADS)

    Hutchinson, John R.; Allen, Vivian

    2009-04-01

    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.

  3. The evolutionary continuum of limb function from early theropods to birds.

    PubMed

    Hutchinson, John R; Allen, Vivian

    2009-04-01

    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 paleontology, 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 paleontological evidence and quantitative assessment of limb function cautiously applied with validated techniques and sensitivity analysis of unknown variables. PMID:19107456

  4. Integration of molecular functions at the ecosystemic level: breakthroughs and future goals of environmental genomics and post-genomics

    PubMed Central

    Vandenkoornhuyse, Philippe; Dufresne, Alexis; Quaiser, Achim; Gouesbet, Gwenola; Binet, Françoise; Francez, André-Jean; Mahé, Stéphane; Bormans, Myriam; Lagadeuc, Yvan; Couée, Ivan

    2010-01-01

    Environmental genomics and genome-wide expression approaches deal with large-scale sequence-based information obtained from environmental samples, at organismal, population or community levels. To date, environmental genomics, transcriptomics and proteomics are arguably the most powerful approaches to discover completely novel ecological functions and to link organismal capabilities, organism–environment interactions, functional diversity, ecosystem processes, evolution and Earth history. Thus, environmental genomics is not merely a toolbox of new technologies but also a source of novel ecological concepts and hypotheses. By removing previous dichotomies between ecophysiology, population ecology, community ecology and ecosystem functioning, environmental genomics enables the integration of sequence-based information into higher ecological and evolutionary levels. However, environmental genomics, along with transcriptomics and proteomics, must involve pluridisciplinary research, such as new developments in bioinformatics, in order to integrate high-throughput molecular biology techniques into ecology. In this review, the validity of environmental genomics and post-genomics for studying ecosystem functioning is discussed in terms of major advances and expectations, as well as in terms of potential hurdles and limitations. Novel avenues for improving the use of these approaches to test theory-driven ecological hypotheses are also explored. PMID:20426792

  5. Integration of molecular functions at the ecosystemic level: breakthroughs and future goals of environmental genomics and post-genomics.

    PubMed

    Vandenkoornhuyse, Philippe; Dufresne, Alexis; Quaiser, Achim; Gouesbet, Gwenola; Binet, Françoise; Francez, André-Jean; Mahé, Stéphane; Bormans, Myriam; Lagadeuc, Yvan; Couée, Ivan

    2010-06-01

    Environmental genomics and genome-wide expression approaches deal with large-scale sequence-based information obtained from environmental samples, at organismal, population or community levels. To date, environmental genomics, transcriptomics and proteomics are arguably the most powerful approaches to discover completely novel ecological functions and to link organismal capabilities, organism-environment interactions, functional diversity, ecosystem processes, evolution and Earth history. Thus, environmental genomics is not merely a toolbox of new technologies but also a source of novel ecological concepts and hypotheses. By removing previous dichotomies between ecophysiology, population ecology, community ecology and ecosystem functioning, environmental genomics enables the integration of sequence-based information into higher ecological and evolutionary levels. However, environmental genomics, along with transcriptomics and proteomics, must involve pluridisciplinary research, such as new developments in bioinformatics, in order to integrate high-throughput molecular biology techniques into ecology. In this review, the validity of environmental genomics and post-genomics for studying ecosystem functioning is discussed in terms of major advances and expectations, as well as in terms of potential hurdles and limitations. Novel avenues for improving the use of these approaches to test theory-driven ecological hypotheses are also explored. PMID:20426792

  6. Defining Planktonic Protist Functional Groups on Mechanisms for Energy and Nutrient Acquisition: Incorporation of Diverse Mixotrophic Strategies.

    PubMed

    Mitra, Aditee; Flynn, Kevin J; Tillmann, Urban; Raven, John A; Caron, David; Stoecker, Diane K; Not, Fabrice; Hansen, Per J; Hallegraeff, Gustaaf; Sanders, Robert; Wilken, Susanne; McManus, George; Johnson, Mathew; Pitta, Paraskevi; Våge, Selina; Berge, Terje; Calbet, Albert; Thingstad, Frede; Jeong, Hae Jin; Burkholder, JoAnn; Glibert, Patricia M; Granéli, Edna; Lundgren, Veronica

    2016-04-01

    Arranging organisms into functional groups aids ecological research by grouping organisms (irrespective of phylogenetic origin) that interact with environmental factors in similar ways. Planktonic protists traditionally have been split between photoautotrophic "phytoplankton" and phagotrophic "microzooplankton". However, there is a growing recognition of the importance of mixotrophy in euphotic aquatic systems, where many protists often combine photoautotrophic and phagotrophic modes of nutrition. Such organisms do not align with the traditional dichotomy of phytoplankton and microzooplankton. To reflect this understanding, we propose a new functional grouping of planktonic protists in an eco-physiological context: (i) phagoheterotrophs lacking phototrophic capacity, (ii) photoautotrophs lacking phagotrophic capacity, (iii) constitutive mixotrophs (CMs) as phagotrophs with an inherent capacity for phototrophy, and (iv) non-constitutive mixotrophs (NCMs) that acquire their phototrophic capacity by ingesting specific (SNCM) or general non-specific (GNCM) prey. For the first time, we incorporate these functional groups within a foodweb structure and show, using model outputs, that there is scope for significant changes in trophic dynamics depending on the protist functional type description. Accordingly, to better reflect the role of mixotrophy, we recommend that as important tools for explanatory and predictive research, aquatic food-web and biogeochemical models need to redefine the protist groups within their frameworks. PMID:26927496

  7. Executive function.

    PubMed

    Talpos, John; Shoaib, Mohammed

    2015-01-01

    Components of human executive function, like rule generation and selection in response to stimuli (attention set-shifting) or overcoming a habit (reversal learning), can be reliably modelled in rodents. The rodent paradigms are based upon tasks that assess cognitive flexibility in clinical populations and have been effective in distinguishing the neurobiological substrates and the underlying neurotransmitter systems relevant to executive function. A review of the literature on the attentional set-shifting task highlights a prominent role for the medial region of the prefrontal cortex in the ability to adapt to a new rule (extradimensional shift) while the orbitofrontal cortex has been associated with the reversal learning component of the task. In other paradigms specifically developed to examine reversal learning in rodents, the orbitofrontal cortex also plays a prominent role. Modulation of dopamine, serotonin, and glutamatergic receptors can disrupt executive function, a feature commonly exploited to develop concepts underlying psychiatric disorders. While these paradigms do have excellent translational construct validity, they have been less effective as predictive preclinical models for cognitive enhancers, especially for cognition in health subjects. Accordingly, a more diverse battery of tasks may be necessary to model normal human executive function in the rodent for drug development. PMID:25977083

  8. 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...

  9. Toll-like receptor 4 deficiency: Smaller infarcts, but nogain in function

    PubMed Central

    Kim, Se-Chan; Ghanem, Alexander; Stapel, Heidi; Tiemann, Klaus; Knuefermann, Pascal; Hoeft, Andreas; Meyer, Rainer; Grohé, Christian; Knowlton, Anne A; Baumgarten, Georg

    2007-01-01

    Backgound It has been reported that Toll-like receptor 4 (TLR4) deficiency reduces infarct size after myocardial ischemia/reperfusion (MI/R). However, measurement of MI/R injury was limited and did not include cardiac function. In a chronic closed-chest model we assessed whether cardiac function is preserved in TLR4-deficient mice (C3H/HeJ) following MI/R, and whether myocardial and systemic cytokine expression differed compared to wild type (WT). Results Infarct size (IS) in C3H/HeJ assessed by TTC staining after 60 min ischemia and 24h reperfusion was significantly smaller than in WT. Despite a smaller infarct size, echocardiography showed no functional difference between C3H/HeJ and WT. Left-ventricular developed pressure measured with a left-ventricular catheter was lower in C3H/HeJ (63.0 ± 4.2 mmHg vs. 77.9 ± 1.7 mmHg in WT, p < 0.05). Serum cytokine levels and myocardial IL-6 were higher in WT than in C3H/HeJ (p < 0.05). C3H/HeJ MI/R showed increased myocardial IL-1β and IL-6 expression compared to their respective shams (p < 0.05), indicating TLR4-independent cytokine activation due to MI/R. Conclusion These results demonstrate that, although a mutant TLR4 signaling cascade reduces myocardial IS and serum cytokine levels, it does not preserve myocardial function. The change in inflammatory response, secondary to a non-functional TLR-4 receptor, may contribute to the observed dichotomy between infarct size and function in the TLR-4 mutant mouse. PMID:17592640

  10. Localising News: Translation and the "Global-National" Dichotomy

    ERIC Educational Resources Information Center

    Orengo, Alberto

    2005-01-01

    Due to the peculiar nature of news texts, the adoption of a theory of "localisation" rather than conventional translation theories accounts more easily for both the commercial nature and the global scale of news distribution. News texts are global products which are distributed through a localisation process involving not only reception by locales…

  11. The Multilingual/Bilingual Dichotomy: An Exploration of Individual Differences

    ERIC Educational Resources Information Center

    Thompson, Amy S.

    2009-01-01

    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…

  12. Space Densities Of AGN And The FR Dichotomy

    NASA Astrophysics Data System (ADS)

    Gendre, Melanie; Wall, J. V.; Best, P. N.

    2011-05-01

    Extended double-lobe radio sources can be morphologically classified into two groups: Fanaroff-Riley (FR) type I sources have the highest surface brightness along the jets near the core and FR type II sources show the highest surface brightness at the lobe extremities, as well as more collimated jets. This work focuses on a comparison of the space densities of FRI and FRII sources at different epochs, with a particular focus on FRI sources. The Combined NVSS-FIRST Galaxy catalogue (CoNFIG), a sample of radio sources at 1.4 GHz, includes VLA observations, FRI/FRII morphology classifications, optical identifications and redshift estimates. The final catalogue consists of 858 sources over 4 samples (CoNFIG-1, 2, 3 and 4 with flux density limits of S_1.4GHz = 1.3, 0.8, 0.2 and 0.05 Jy respectively). It is 95.7% complete in radio morphology classification and 74.3% of the sources have redshift data. Combining CoNFIG with complementary samples, the distribution and cosmic evolution of FRI and FRII sources are investigated. It is found that FRI sources undergo mild evolution and that, at the same radio luminosity, FRI and FRII sources show similar space density enhancements in various redshift ranges, implying a common mechanism powering the luminosity-dependent evolution. This improved understanding of radio galaxy evolution will also give better insight into the the physics of AGN and their role in galaxy formation.

  13. "Murrayesque" Expressivism: A Deweyan Reconsideration of Contemporary Composition's Dangerous Dichotomies.

    ERIC Educational Resources Information Center

    Jones, Don

    Like the narrator of Robert Frost's poem "Mending Wall," instructors need to ask what is being walled in and walled out of their composition programs when categories such as process vs. product, expressive, epistemic, current traditionalism, and social constructionism are constructed. When divisive categories prevent theorists from receiving…

  14. Dichotomy of protective cellular immune responses to human visceral leishmaniasis

    PubMed Central

    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

    2005-01-01

    Healing/protective responses in human visceral leishmaniasis (VL) are associated with stimulation/production of Th1 cytokines, such as interferon IFN-γ, 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–Guérin (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-γ 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-γ levels (mean 1008 ± 395; median 1247 pg/ml). Five volunteers had significant L. donovani antigen-induced IFN-γ 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-γ levels (mean 110 ± 124 pg/ml; median 80) and were non-reactive in LST (induration = 00 mm). The remaining eight volunteers had low IFN-γ 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-γ (mean 66·0 ± 62 pg/ml; P > 0.05). Eleven volunteers (11/44; 25%) had significantly high levels of IFN-γ and LST induration, while five volunteers had low levels of IFN-γ (<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-γ production and the LST response are not in a causal relationship. Following vaccination and probably cure of VL infection, the IFN-γ 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

  15. Content vs. Learning: An Old Dichotomy in Science Courses

    ERIC Educational Resources Information Center

    Bergtrom, Gerald

    2011-01-01

    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…

  16. The Rural Education Dichotomy: Disadvantaged Systems and School Strengths.

    ERIC Educational Resources Information Center

    Dunn, Randy J.

    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…

  17. Paradigms, Perspectives and Dichotomies amongst Teacher Educators in Hong Kong

    ERIC Educational Resources Information Center

    Katyal, Kokila Roy; Fai, Pang Ming

    2010-01-01

    This paper argues that the concepts, beliefs and understandings of local and non-local teacher educators in a Hong Kong university are grounded in their own cultural cognition and antecedents. It presents the viewpoint that contemporary notions of good practice were compromised when applied to a context that is strongly influenced by the tenets of…

  18. Unmasking Moral Dichotomies: Can Feminist Pedagogy Overcome Student Resistance?

    ERIC Educational Resources Information Center

    Markowitz, Linda

    2005-01-01

    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…

  19. John Dewey's pragmatist alternative to the belief-acceptance dichotomy.

    PubMed

    Brown, Matthew J

    2015-10-01

    Defenders of value-free science appeal to cognitive attitudes as part of a wedge strategy, to mark a distinction between science proper and the uses of science for decision-making, policy, etc. Distinctions between attitudes like belief and acceptance have played an important role in defending the value-free ideal. In this paper, I will explore John Dewey's pragmatist philosophy of science as an alternative to the philosophical framework the wedge strategy rests on. Dewey does draw significant and useful distinctions between different sorts of cognitive attitudes taken by inquirers, but none can be used to support the wedge strategy. PMID:26386531

  20. Drowning in Dichotomy: Interpreting "The Drowning of Stephan Jones."

    ERIC Educational Resources Information Center

    Finnessy, Patrick K.

    1998-01-01

    Presents a negative critique of Bette Greene's novel "The Drowning of Stephan Jones." Suggests that while Greene tries to break stereotypes of homosexuals, she reinforces other societal stereotypes, thus "drowning the novel's strengths." (RS)

  1. Isotope Analysis Reveals Foraging Area Dichotomy for Atlantic Leatherback Turtles

    PubMed Central

    Angulo, Elena; Das, Krishna; Girondot, Marc

    2008-01-01

    Background The leatherback turtle (Dermochelys coriacea) has undergone a dramatic decline over the last 25 years, and this is believed to be primarily the result of mortality associated with fisheries bycatch followed by egg and nesting female harvest. Atlantic leatherback turtles undertake long migrations across ocean basins from subtropical and tropical nesting beaches to productive frontal areas. Migration between two nesting seasons can last 2 or 3 years, a time period termed the remigration interval (RI). Recent satellite transmitter data revealed that Atlantic leatherbacks follow two major dispersion patterns after nesting season, through the North Gulf Stream area or more eastward across the North Equatorial Current. However, information on the whole RI is lacking, precluding the accurate identification of feeding areas where conservation measures may need to be applied. Methodology/Principal Findings Using stable isotopes as dietary tracers we determined the characteristics of feeding grounds of leatherback females nesting in French Guiana. During migration, 3-year RI females differed from 2-year RI females in their isotope values, implying differences in their choice of feeding habitats (offshore vs. more coastal) and foraging latitude (North Atlantic vs. West African coasts, respectively). Egg-yolk and blood isotope values are correlated in nesting females, indicating that egg analysis is a useful tool for assessing isotope values in these turtles, including adults when not available. Conclusions/Significance Our results complement previous data on turtle movements during the first year following the nesting season, integrating the diet consumed during the year before nesting. We suggest that the French Guiana leatherback population segregates into two distinct isotopic groupings, and highlight the urgent need to determine the feeding habitats of the turtle in the Atlantic in order to protect this species from incidental take by commercial fisheries. Our results also emphasize the use of eggs, a less-invasive sampling material than blood, to assess isotopic data and feeding habits for adult female leatherbacks. PMID:18365003

  2. The Policy-Practice Dichotomy: Can We Straddle the Divide?

    ERIC Educational Resources Information Center

    Blignaut, Sylvan

    2007-01-01

    In this article I review the literature on a topical issue in education generally and curriculum implementation in particular, namely why it is so difficult to translate policy into practice. How do we come to understand policy and its link(s) to what actually happens inside classrooms? I locate the inquiry within the broader literature on…

  3. The aging-disease false dichotomy: understanding senescence as pathology

    PubMed Central

    Gems, David

    2015-01-01

    From a biological perspective aging (senescence) appears to be a form of complex disease syndrome, though this is not the traditional view. This essay aims to foster a realistic understanding of aging by scrutinizing ideas old and new. The conceptual division between aging-related diseases and an underlying, non-pathological aging process underpins various erroneous traditional ideas about aging. Among biogerontologists, another likely error involves the aspiration to treat the entire aging process, which recent advances suggest is somewhat utopian. It also risks neglecting a more modest but realizable goal: to develop preventative treatments that partially protect against aging. PMID:26136770

  4. Avian energetics: The passerine/non-passerine dichotomy.

    PubMed

    McNab, Brian K

    2016-01-01

    Whether passerines collectively have a higher mean mass-independent basal rate of metabolism than the mean of other birds has been controversial. The conclusion that no difference exists was based on phylogenetic analyses. Higher basal rates, however, have been repeatedly seen in passerines and demonstrated by ANCOVA analyses. Several studies indicated that the mean mass-independent basal rate of passerines is >30% higher than the collective mean of other birds. Yet, at least three non-passerine orders of 25 have mean mass-independent basal rates equal to that of passerines. They are Anseriformes, Charadriiformes, and Procellariiformes, all characterized by an active lifestyle, including migratory and pelagic habits. In contrast, sedentary ducks endemic to islands have low basal rates. The high basal rates in temperate passerines correlate with migratory habits and life in cool to cold environments, the absence of these factors being partly responsible for the lower basal rates in most tropical passerines. The principal difference in energetics among non-passerines, between passerines and most non-passerines, and among passerines reflects the frequency of habits associated with high or low mass-independent energy expenditures, the habits correlating with body composition. The mean mass-independent basal rate in tropical passerines is slightly lower than in temperate passerines which implies that the collective mean in passerines would be somewhat lower if tropical passerines were included in proportion to their diversity. However, their inclusion will not eliminate the difference presently seen between passerines and other birds because the difference between tropical and temperate passerines is less than that between passerines and other birds. PMID:26456419

  5. A dichotomy in primary marine organic aerosol cloud interaction

    NASA Astrophysics Data System (ADS)

    Facchini, C.; Ovadnevaite, J.; Ceburnis, D.; Martucci, G.; Bialek, J.; Monahan, C.; Rinaldi, M.; Berresheim, H.; Worsnop, D. R.; O'Dowd, C.

    2012-12-01

    A significant contribution of insoluble organic matter to marine aerosol has been proved to be of biogenic origin. High time resolution measurements of marine organic matter have demonstrated a dynamic system with regular organic matter plume events occurring during summer as well as frequent open ocean particle formation events. High-time resolution measurements of primary marine organic sea-spray physico-chemical properties reveal an apparent dichotomous behavior in terms of water uptake: specifically sea-spray aerosol enriched in organic matter possesses a low hygroscopic Growth Factor (GF~1.25) while simultaneously having a cloud condensation nucleus/condensation nuclei (CCN/CN) activation efficiency of between 83% at 0.25% supersaturation and 100% at 0.75%5. Simultaneous measurements of Cloud Droplet Number Concentration (CDNC) during primary organic aerosol plumes reveal CDNC concentrations of 350 cm-3 in newly formed marine stratocumulus cloud for boundary layer organic mass concentrations of 3-4 μg m-3. It is suggested that marine hydrogels are responsible for this dichotomous behavior which has profound impacts to aerosol-cloud-climate system along with a better understood process analysis of aerosol formation by sea-spray. A hydrophobic character of organic matter dominated aerosol in sub-saturated conditions should have significant implications for direct radiative effect while effectively forming cloud condensation nuclei should have significant contribution to indirect effect.

  6. Graph Hypersurfaces and a Dichotomy in the Grothendieck Ring

    NASA Astrophysics Data System (ADS)

    Aluffi, Paolo; Marcolli, Matilde

    2011-03-01

    The subring of the Grothendieck ring of varieties generated by the graph hypersurfaces of quantum field theory maps to the monoid ring of stable birational equivalence classes of varieties. We show that the image of this map is the copy of {mathbb{Z}} generated by the class of a point. This clarifies the extent to which the graph hypersurfaces `generate the Grothendieck ring of varieties': while it is known that graph hypersurfaces generate the Grothendieck ring over a localization of {mathbb{Z}[mathbb{L}]} in which {mathbb{L}} becomes invertible, the span of the graph hypersurfaces in the Grothendieck ring itself is nearly killed by setting the Lefschetz motive {mathbb{L}} to zero. In particular, this shows that the graph hypersurfaces do not generate the Grothendieck ring prior to localization. The same result yields some information on the mixed Hodge structures of graph hypersurfaces, in the form of a constraint on the terms in their Deligne-Hodge polynomials. These observations are certainly not surprising for the expert reader, but are somewhat hidden in the literature. The treatment in this note is straightforward and self-contained.

  7. Avoiding Moral Dichotomies: Teaching Controversial Topics to Resistant Students.

    ERIC Educational Resources Information Center

    Markowitz, Linda; Hedley, Mark

    2001-01-01

    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.…

  8. The dichotomy of pathogens and allergens in vaccination approaches

    PubMed Central

    Baird, Fiona J.; Lopata, Andreas L.

    2014-01-01

    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

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

    ERIC Educational Resources Information Center

    Wozniak, Anna

    2006-01-01

    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

  10. Toward Integration Through Education: Dichotomies of Purposes and Processes.

    ERIC Educational Resources Information Center

    Gibson, John S.

    Beginning with the thesis that integrated education is indispensable to achieving an integrated society, the author examines first whether these assumptions behind school desegregation are valid or not, and why: that students will perform better academically, and that more democratic human relations will ensue. He presents evidence to show that…

  11. The Multilingual/Bilingual Dichotomy: An Exploration of Individual Differences

    ERIC Educational Resources Information Center

    Thompson, Amy S.

    2009-01-01

    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

  12. Transcending the Mind-Body Dichotomy: Schizophrenia Reexamined.

    ERIC Educational Resources Information Center

    Bemak, Fred; Epp, Lawrence R.

    2002-01-01

    Discusses how the genetic aspects of schizophrenia must be described within the interactive context of psychosocial stress. Suggests that the mental health profession must consider the environmental and social components of this condition, including the clients' relationships, families, and communities. States that psychotherapeutic interventions…

  13. [The development of gender identity beyond rigid dichotomy].

    PubMed

    Quindeau, Ilka

    2014-01-01

    The conflicts individuals with ambiguous sexual characteristics suffer from are not the result of genetic features but of the rigid and dichotomous gender order, which is currently undergoing a renaissance. This also applies to individuals with an uncertain gender identity. In the best interests of the child a concept of gender seems necessary, that goes beyond a binary separation and allows gender-specific intermediary stages in the personal development of identity. Such a gender concept can be developed following psychoanalytic theories. The present discourse contains a scale of connecting factors for a differentiated and less normative conceptualization of gender development. Starting from Freud's concept of constitutional bisexuality, Robert Stoller's theory, which has been firmly rooted in the mainstream of psychoanalysis for more than 40 years, will be critically reviewed. By involving Reimut Reiche's and Jean Laplanche's arguments, a continuative psychological gender theory will be drafted, which does not normatively and reductively claim the demarcation of gender, but rather opens up a space for gender diversity. PMID:25296507

  14. The Demise of the Nature-Nurture Dichotomy.

    ERIC Educational Resources Information Center

    Lerner, Richard M.

    1993-01-01

    Maintains that "Individual Development and Evolution: The Genesis of Novel Behavior" (Gilbert Gottlieb) is one of the most creative, integrative, and important works in the field of developmental comparative science. Gottlieb's work has provided scientific basis for the concept that developmental systems, and not genetic reductionism, is the only…

  15. Tolerance to Alliance: Deconstructing Dichotomies to Advocate for All Students

    ERIC Educational Resources Information Center

    Berg, Margaret

    2013-01-01

    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…

  16. Tolerance to Alliance: Deconstructing Dichotomies to Advocate for All Students

    ERIC Educational Resources Information Center

    Berg, Margaret

    2013-01-01

    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

  17. Educating Moral Emotions or Moral Selves: A False Dichotomy?

    ERIC Educational Resources Information Center

    Kristjansson, Kristjan

    2010-01-01

    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…

  18. Dialectics Instead of Dichotomy: Perspectives on the Twin Ambitions Movement

    ERIC Educational Resources Information Center

    Eriksson, Lisbeth

    2013-01-01

    This article discusses the mobilizing work of a disability organization, at the local chapter level. I have spent about a year following the work of a chapter, mainly through contacts, conversations and interviews with the persons who are active on its board. The analysis of the chapter's work takes as its starting point two traditions that…

  19. Comprehensive functional annotation of 18 missense mutations found in suspected hemochromatosis type 4 patients.

    PubMed

    Callebaut, Isabelle; Joubrel, Rozenn; Pissard, Serge; Kannengiesser, Caroline; Gérolami, Victoria; Ged, Cécile; Cadet, Estelle; Cartault, François; Ka, Chandran; Gourlaouen, Isabelle; Gourhant, Lénaick; Oudin, Claire; Goossens, Michel; Grandchamp, Bernard; De Verneuil, Hubert; Rochette, Jacques; Férec, Claude; Le Gac, Gérald

    2014-09-01

    Hemochromatosis type 4 is a rare form of primary iron overload transmitted as an autosomal dominant trait caused by mutations in the gene encoding the iron transport protein ferroportin 1 (SLC40A1). SLC40A1 mutations fall into two functional categories (loss- versus gain-of-function) underlying two distinct clinical entities (hemochromatosis type 4A versus type 4B). However, the vast majority of SLC40A1 mutations are rare missense variations, with only a few showing strong evidence of causality. The present study reports the results of an integrated approach collecting genetic and phenotypic data from 44 suspected hemochromatosis type 4 patients, with comprehensive structural and functional annotations. Causality was demonstrated for 10 missense variants, showing a clear dichotomy between the two hemochromatosis type 4 subtypes. Two subgroups of loss-of-function mutations were distinguished: one impairing cell-surface expression and one altering only iron egress. Additionally, a new gain-of-function mutation was identified, and the degradation of ferroportin on hepcidin binding was shown to probably depend on the integrity of a large extracellular loop outside of the hepcidin-binding domain. Eight further missense variations, on the other hand, were shown to have no discernible effects at either protein or RNA level; these were found in apparently isolated patients and were associated with a less severe phenotype. The present findings illustrate the importance of combining in silico and biochemical approaches to fully distinguish pathogenic SLC40A1 mutations from benign variants. This has profound implications for patient management. PMID:24714983

  20. 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

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

    2014-01-01

    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

  1. Executive Functions

    PubMed Central

    Diamond, Adele

    2014-01-01

    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

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

    NASA Technical Reports Server (NTRS)

    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

    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.

  3. Function of pectoral fins in rainbow trout: behavioral repertoire and hydrodynamic forces.

    PubMed

    Drucker, Eliot G; Lauder, George V

    2003-03-01

    Salmonid fishes (trout, salmon and relatives) have served as a model system for study of the mechanics of aquatic animal locomotion, yet little is known about the function of non-axial propulsors in this major taxonomic group. In this study we examine the behavioral and hydromechanical repertoire of the paired pectoral fins of rainbow trout Oncorhynchus mykiss, performing both steady rectilinear swimming and unsteady maneuvering locomotion. A combination of kinematic analysis and quantitative flow visualization (using digital particle image velocimetry) enables identification of the propulsive roles played by pectoral fin motions. During constant-speed swimming (0.5 and 1.0 body length s(-1)), the pectoral fins remain adducted against the body. These fins are actively recruited, however, for a variety of maneuvering behaviors, including station holding in still water (hovering), low-speed (i.e. non-fast-start) turning, and rapid deceleration of the body during braking. Despite having a shallow pectoral-fin base orientation (the plesiomorphic teleost condition), trout are capable of rotating the fin base over 30 degrees during maneuvering, which affords the fin an impressive degree of kinematic versatility. When hovering, the pectoral fins are depressed beneath the body and twisted along their long axes to allow anteroposterior sculling. During turning and braking, the fins undergo spanwise rotation in the opposite direction and exhibit mediolateral and dorsoventral excursions. Water velocity fields and calculated momentum flows in the wake of the pectoral fins reveal that positive thrust is not generated during maneuvering, except during the retraction half-stroke of hovering. Relatively large laterally directed fluid force (mean 2.7 mN) is developed during turning, whose reaction powers yawing rotation of the body (4-41 degrees s(-1)). During deceleration, the wake-force line of action falls below the center of mass of the body, and this result supports a long-standing mechanical model of braking by fishes with ventrally positioned paired fins. Despite its traditional categorization as a propulsor of limited functional importance, the salmoniform pectoral fin exhibits a diverse locomotor repertoire comparable to that of higher teleostean fishes. PMID:12547936

  4. Blockade of Immunosuppressive Cytokines Restores NK Cell Antiviral Function in Chronic Hepatitis B Virus Infection

    PubMed Central

    Peppa, Dimitra; Micco, Lorenzo; Javaid, Alia; Kennedy, Patrick T. F.; Schurich, Anna; Dunn, Claire; Pallant, Celeste; Ellis, Gidon; Khanna, Pooja; Dusheiko, Geoffrey; Gilson, Richard J.; Maini, Mala K.

    2010-01-01

    NK cells are enriched in the liver, constituting around a third of intrahepatic lymphocytes. We have previously demonstrated that they upregulate the death ligand TRAIL in patients with chronic hepatitis B virus infection (CHB), allowing them to kill hepatocytes bearing TRAIL receptors. In this study we investigated whether, in addition to their pathogenic role, NK cells have antiviral potential in CHB. We characterised NK cell subsets and effector function in 64 patients with CHB compared to 31 healthy controls. We found that, in contrast to their upregulated TRAIL expression and maintenance of cytolytic function, NK cells had a markedly impaired capacity to produce IFN-γ in CHB. This functional dichotomy of NK cells could be recapitulated in vitro by exposure to the immunosuppressive cytokine IL-10, which was induced in patients with active CHB. IL-10 selectively suppressed NK cell IFN-γ production without altering cytotoxicity or death ligand expression. Potent antiviral therapy reduced TRAIL-expressing CD56bright NK cells, consistent with the reduction in liver inflammation it induced; however, it was not able to normalise IL-10 levels or the capacity of NK cells to produce the antiviral cytokine IFN-γ. Blockade of IL-10 +/− TGF-β restored the capacity of NK cells from both the periphery and liver of patients with CHB to produce IFN-γ, thereby enhancing their non-cytolytic antiviral capacity. In conclusion, NK cells may be driven to a state of partial functional tolerance by the immunosuppressive cytokine environment in CHB. Their defective capacity to produce the antiviral cytokine IFN-γ persists in patients on antiviral therapy but can be corrected in vitro by IL-10+/− TGF-β blockade. PMID:21187913

  5. Blockade of immunosuppressive cytokines restores NK cell antiviral function in chronic hepatitis B virus infection.

    PubMed

    Peppa, Dimitra; Micco, Lorenzo; Javaid, Alia; Kennedy, Patrick T F; Schurich, Anna; Dunn, Claire; Pallant, Celeste; Ellis, Gidon; Khanna, Pooja; Dusheiko, Geoffrey; Gilson, Richard J; Maini, Mala K

    2010-01-01

    NK cells are enriched in the liver, constituting around a third of intrahepatic lymphocytes. We have previously demonstrated that they upregulate the death ligand TRAIL in patients with chronic hepatitis B virus infection (CHB), allowing them to kill hepatocytes bearing TRAIL receptors. In this study we investigated whether, in addition to their pathogenic role, NK cells have antiviral potential in CHB. We characterised NK cell subsets and effector function in 64 patients with CHB compared to 31 healthy controls. We found that, in contrast to their upregulated TRAIL expression and maintenance of cytolytic function, NK cells had a markedly impaired capacity to produce IFN-γ in CHB. This functional dichotomy of NK cells could be recapitulated in vitro by exposure to the immunosuppressive cytokine IL-10, which was induced in patients with active CHB. IL-10 selectively suppressed NK cell IFN-γ production without altering cytotoxicity or death ligand expression. Potent antiviral therapy reduced TRAIL-expressing CD56(bright) NK cells, consistent with the reduction in liver inflammation it induced; however, it was not able to normalise IL-10 levels or the capacity of NK cells to produce the antiviral cytokine IFN-γ. Blockade of IL-10 +/- TGF-β restored the capacity of NK cells from both the periphery and liver of patients with CHB to produce IFN-γ, thereby enhancing their non-cytolytic antiviral capacity. In conclusion, NK cells may be driven to a state of partial functional tolerance by the immunosuppressive cytokine environment in CHB. Their defective capacity to produce the antiviral cytokine IFN-γ persists in patients on antiviral therapy but can be corrected in vitro by IL-10+/- TGF-β blockade. PMID:21187913

  6. Functional amyloid

    PubMed Central

    2010-01-01

    Evidence is growing at an increasing-pace that amyloid fibers are not just the result of aberrant protein folding associated with neurodegenerative diseases, but are widespread in nature for beneficial reasons. Amyloid is an attractive building material because its robust design and simple repetitive structure make for very durable and metabolically cheap material. But this requires that the production of amyloid be put under firm control. This appears to involve the use of four to five chaperones that are expressed under the control of the same promoter as the amyloid proteins. Significant progress has been made in deciphering this process in E. coli's csg operon, also found in Salmonella. Recently, we have discovered a new and unrelated operon (fap) responsible for amyloid production in Pseudomonas, which also confers biofilm-forming properties to E. coli. Intriguingly, this operon shares a number of features with csg, namely two homologous proteins (one of which, FapC, has been shown to be directly involved in amyloid build-up) and a small number of auxiliary proteins. However, FapC seems to be less economically structured than its E. coli counterpart, with a smaller number of repeats and very large and variable linker regions. Furthermore, the putative chaperones are not homologous to their csg counterparts and have intriguing homologies to proteins with other functions. These findings suggest that controlled amyloid production has arisen on many independent occasions due to the usefulness of the product and offers the potential for intriguing insights into how nature disarms and reconstructs a potentially very dangerous weapon. PMID:20935497

  7. Distribution functions for magnetic fields on the quiet Sun

    NASA Astrophysics Data System (ADS)

    Stenflo, J. O.

    2010-07-01

    The statistical properties of the highly structured magnetic field of the quiet Sun are best described in terms of distribution functions, in particular the probability density functions (PDF) for the flux densities and the angular distribution for the orientations of the field vector. They are needed to test the validity of various MHD simulations, but past determinations have led to contradictory results. A main reason for these difficulties lies in the circumstance that the magnetic structuring continues on scales that are much smaller than the telescope resolution, and that this structuring strongly affects the quantities averaged over each pixel due to the non-linear relation between polarization and magnetic field. Here we use a Hinode SOT/SP data set for the disk center of the quiet Sun to explore the complex behavior of the polarized 6301-6302 Å line system and identify the observables that allow the most robust determinations of inclination angles and flux densities. These observables are then used to derive the empirical distribution functions. Our Stokes V line ratio analysis leads us to an unexpected discovery: a magnetic dichotomy with two distinct populations, representing strong (kG) and weak fields. This can be understood in terms of the convective collapse mechanism, which makes the Sun's magnetic flux end up in two states: collapsed and uncollapsed. With the linear-to-circular polarization ratio as a robust observable for the inclination angles, we find that the angular distribution is extremely peaked around the vertical direction for the largest flux densities, but gradually broadens as we go to smaller flux densities, to become asymptotically isotropic at zero flux density. The PDF for the vertical flux density, after accounting for the smearing effect of measurement noise, is found to have an extremely narrow core peak centered at zero flux density, which can be analytically represented by a stretched exponential. The PDF wings are extended and decline quadratically. The PDFs for the horizontal and total flux densities have a similar behavior. In particular we demonstrate that earlier claims that the PDF for the total flux density increases from small values at zero flux density to have a maximum significantly shifted from zero is an artefact of measurement noise.

  8. Density-matrix functionals from Green's functions

    NASA Astrophysics Data System (ADS)

    Blöchl, Peter E.; Pruschke, Thomas; Potthoff, Michael

    2013-11-01

    The exact reduced density-matrix functional is derived from the Luttinger-Ward functional of the single-particle Green's function. Thereby, a formal link is provided between diagrammatic many-body approaches using Green's functions on the one hand and theories based on many-body wave functions on the other. This link can be used to explicitly construct approximations for the density-matrix functional that are equivalent to standard diagrammatic resummation techniques and to nonperturbative dynamical mean field theory in particular. Contrary to functionals of the Green's function, the exact density-matrix functional is convex and thus provides a true minimum principle which facilitates the calculation of the grand potential and derived equilibrium properties. The benefits of the proposed Green's-function-based density-matrix functional theory for geometrical structure optimization of strongly correlated materials are discussed.

  9. Functional Training Revisited.

    ERIC Educational Resources Information Center

    Siff, Mel C.

    2002-01-01

    Asserts that though functional training is vital in all sporting preparation, it is only one aspect of the overall process. The paper defines functional training; discusses facets of functionality, functionality and balancing drills, and functional training and periodization; and concludes that functionality is best defined in terms of the outcome…

  10. [Psychological function in aging].

    PubMed

    Wada, Kenji; Yamamoto, Mikie; Nakashima, Kenji

    2013-10-01

    Physical function was declined in aging as well as sensory function in human. Motor slowness and unbalance gait occur as well as decline of ability visual acuity and hearing let elderly people live in limited daily activity. Psychological functions are also thought to be decline in aging. In International Classification of Functioning, Disability and Health(ICF), psychological functions are classified into attention, memory, psychomotor, emotion, perception, thought, higher-level cognitive functions, language, calculation, sequencing complex movements, experience of self and time functions and unspecified functions. It is difficult to assess an individual psychological function itself, because some functions may affect each other and results of evaluations of a psychological function may not represent the meaning of the function. There were numerous reports on physical function in aging in a cross sectional or a longitudinal study design. In this article, we review changes of psychological function in aging. PMID:24261197

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

    ERIC Educational Resources Information Center

    Leisman, Gerald; Schwartz, Joddy

    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…

  12. Calculator Function Approximation.

    ERIC Educational Resources Information Center

    Schelin, Charles W.

    1983-01-01

    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)

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

    PubMed Central

    Jamon, Marc

    2013-01-01

    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

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

    PubMed

    Jamon, Marc

    2014-01-01

    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

  15. Density functional Green`s Function Theory

    SciTech Connect

    Sham, L.J.

    1996-12-31

    Density Functional Theory is designed to treat the interacting electron system in the presence of an external potential which makes the density of the electrons inhomogeneous. The Green`s function method provides a way to construct the exact energy functionals, especially the exchange-correlation potential and systematic approximations for numerical evaluation. I shall discuss the philosophy of this approach versus others and give a cursory review of the applications to insulators and semiconductors, to interfaces, and to strongly-correlated metals.

  16. Wave-function functionals for the density

    SciTech Connect

    Slamet, Marlina; Pan Xiaoyin; Sahni, Viraht

    2011-11-15

    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.

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

    PubMed Central

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

    2012-01-01

    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

  18. Investigating function and connectivity of morphometric findings — Exemplified on cerebellar atrophy in spinocerebellar ataxia 17 (SCA17)

    PubMed Central

    Reetz, Kathrin; Dogan, Imis; Rolfs, Arndt; Binkofski, Ferdinand; Schulz, Jörg B.; Laird, Angela R.; Fox, Peter T.; Eickhoff, Simon B.

    2016-01-01

    Spinocerebellar ataxia type 17 (SCA17) is a rare autosomal dominant neurodegenerative disorder characterized by progressive cerebellar ataxia but also a broad spectrum of other neuropsychiatric signs. As anatomical and structural studies have shown severe cerebellar atrophy in SCA17 and a differentiation of the human cerebellum into an anterior sensorimotor and posterior cognitive/emotional partition has been implicated, we aimed at investigating functional connectivity patterns of two cerebellar clusters of atrophy revealed by a morphometric analysis in SCA17 patients. In particular, voxel-based morphometry (VBM) revealed a large cluster of atrophy in SCA17 in the bilateral anterior cerebellum (lobule V) and another one in the left posterior cerebellum (lobules IX, VIIb, VIIIA, VIIIB). These two cerebellar clusters were used as seeds for functional connectivity analyses using task-based meta-analytic connectivity modeling (MACM) and task-free resting state connectivity analysis. Results demonstrated first consistent functional connectivity throughout the cerebellum itself; the anterior cerebellar seed showed stronger connectivity to lobules V, VI and to some extent I–IV, and the posterior cerebellar seed to the posterior lobules VI–IX. Importantly, the cerebellar anterior seed also showed consistently stronger functional connectivity than the posterior one with pre- and motor areas as well as the primary somatosensory cortex. In turn, task-based task-independent functional connectivity analyses revealed that the cerebellar posterior seed was linked with fronto-temporo-parietal areas as well as partly the insula and the thalamus, i.e., brain regions implicated in cognitive and affective processes. Functional characterization of experiments activating either cerebellar seed further corroborated this notion, revealing mainly motor-related functions for the anterior cluster and predominantly cognitive functions were associated for the posterior one. The differential functional connectivity of the cerebellar anterior and posterior cluster highlights the manifold connections and dichotomy of the human cerebellum, providing additional valuable information about probably disrupted cerebellar–cerebral connections and reflecting the brunt of motor but also the broad spectrum of neuropsychiatric deficits in SCA17. PMID:22659444

  19. E-Orbit Functions

    NASA Astrophysics Data System (ADS)

    Klimyk, Anatoliy U.; Patera, Jiri

    2008-01-01

    We review and further develop the theory of E-orbit functions. They are functions on the Euclidean space En obtained from the multivariate exponential function by symmetrization by means of an even part We of a Weyl group W, corresponding to a Coxeter-Dynkin diagram. Properties of such functions are described. They are closely related to symmetric and antisymmetric orbit functions which are received from exponential functions by symmetrization and antisymmetrization procedure by means of a Weyl group W. The E-orbit functions, determined by integral parameters, are invariant with respect to even part Weaff of the affine Weyl group corresponding to W. The E-orbit functions determine a symmetrized Fourier transform, where these functions serve as a kernel of the transform. They also determine a transform on a finite set of points of the fundamental ! domain Fe of the group Weaff (the discrete E-orbit function transform).

  20. Optimal Stimulus Amplitude for Vestibular Stochastic Stimulation to Improve Sensorimotor Function

    NASA Technical Reports Server (NTRS)

    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

    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.

  1. CD8 sup + T lymphocytes of patients with AIDS maintain normal broad cytolytic function despite the loss of human immunodeficiency virus-specific cytotoxicity

    SciTech Connect

    Pantaleo, G.; De Maria, A.; Koenig, S.; Butini, L.; Moss, B.; Lane, H.C.; Fauci, A.S. ); Baseler, M. )

    1990-06-01

    In this study, the authors have investigated the potential mechanisms responsible for the loss of human immunodeficiency virus type 1 (HIV-1)-specific cytolytic activity in the advanced stages of HIV-1 infection. They have demonstrated that HIV-1-specific cytotoxic T lymphocytes are predominantly contained within the CD8{sup +}DR{sup +} subset. Furthermore, they have shown by a redirected killing assay that there is a dichotomy between HIV-1-specific cytolytic activity and broad cytolytic potential since the cytolytic machinery of CD8{sup +}DR{sup +} cells is still functioning even in patients with AIDS who have lost their HIV-1-specific cytolytic activity. In addition, by comparative analysis of these two types of cytolytic activity over time they have demonstrated a progressive loss of HIV-1-specific cytolytic activity in the advanced stages of the disease, whereas the cytolytic potential remained unchanged regardless of the clinical stage. On the basis of these results, they propose that the loss of HIV-1-specific cytolytic activity in HIV-1-infected individuals may result at least in part from a progressive decrease in the pool of HIV-1-specific cytotoxic T lymphocytes belonging to the CD8{sup +}DR{sup +} subset whose ability to expand has been impaired.

  2. Sampling functions for geophysics

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

    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.

  3. Functional foods: psychological and behavioural functions.

    PubMed

    Dye, Louise; Blundell, John

    2002-11-01

    It is easier to demonstrate the consistent effects of foods on satiety than on cognitive performance. This is understandable since the satiety system incorporates physiological signalling systems that mediate the effects of foods on function. Specific manipulations of proteins, carbohydrates and fats have the potential to act as functional foods for appetite control. Because of the importance of the optimal functioning of cognitions for survival, these functions are quite strongly protected against short-term dietary and physiological perturbances. Therefore, food manipulations may be better detected through the degree of effort exerted to maintain performance rather than via changes in the actual performance itself. This procedure has not been widely used hitherto. The concept of biomarkers may have to be interpreted differently from research on physiological systems or clinical endpoints. For satiety, adjustments in the profile of hunger could serve as a biomarker or surrogate endpoint. For cognitions, correlated physiological variables may be more difficult to measure than the functional endpoint itself. Changes related to unitary functions (such as tracking) could serve as biomarkers for more complex, integrated skills (such as car driving). Since food manipulations may affect multiple functions, the challenge is to design foods with good satiety control that do not impair mental performance; or alternatively to engineer foods that optimise cognitive performance without compromising satiety. This rapidly developing field has great potential for close collaboration between academia and industry in the production of commercially successful products that show clear improvements in human functioning with the capacity to protect against disease or impairment. PMID:12495461

  4. From functional architecture to functional connectomics

    PubMed Central

    Reid, R.Clay

    2013-01-01

    Hubel and Wiesel‘s 1962 paper, “Receptive fields, binocular interaction and functional architecture in the cat“s visual cortex” reported several important discoveries: orientation columns, the distinct structures of simple and complex receptive fields, and binocular integration. But perhaps the paper‘s greatest influence came from the concept of functional architecture (the complex relationship between in vivo physiology and the spatial arrangement of neurons) and several models of functionally specific connectivity. They thus identified two distinct concepts, topographic specificity and functional specificity, which together with cell-type specificity constitute the major determinants of cortical connectivity. Orientation columns are iconic examples of topographic specificity, whereby axons within a column connect with cells of a single orientation preference. Hubel and Wiesel also saw the need for functional specificity at a finer scale, in their model of thalamic inputs to simple cells, verified in the 1990s. The difficult but potentially more important question of intracortical functional specificity is only now becoming tractable with new experimental techniques. PMID:22841307

  5. Functionalized boron nitride nanotubes

    DOEpatents

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

    2014-04-22

    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.

  6. Photon structure function - theory

    SciTech Connect

    Bardeen, W.A.

    1984-12-01

    The theoretical status of the photon structure function is reviewed. Particular attention is paid to the hadronic mixing problem and the ability of perturbative QCD to make definitive predictions for the photon structure function. 11 references.

  7. Extraocular muscle function testing

    MedlinePlus

    Extraocular muscle function testing examines the function of the eye muscles. A health care provider observes the movement of ... evaluate weakness or other problem in the extraocular muscles. These problems may result in double vision or ...

  8. Liver Function Tests

    MedlinePlus

    ... food, store energy, and remove poisons. Liver function tests are blood tests that check to see how well your liver ... hepatitis and cirrhosis. You may have liver function tests as part of a regular checkup. Or you ...

  9. [Functional gastrointestinal disorders].

    PubMed

    Halama, Marcel

    2015-08-01

    Functional gastrointestinal complaints are very common in daily clinic practice. Functional gastrointestinal disorders are characterized in disturbances of motility patterns and/or of visceral hypersensitivity. The main functional gastrointestinal disorders are functional dyspepsia and irritable bowel syndrome. There is no causative therapy, but we have many medication and also non-medication therapeutic options which all can be tried on an indivual basis. PMID:26242420

  10. Pain and Hand Function.

    PubMed

    Howland, Nicholas; Lopez, Mariela; Zhang, Andrew Y

    2016-02-01

    Pain is a unique somatosensory perception that can dramatically affect our ability to function. It is also a necessary perception, without which we would do irreparable damage to ourselves. In this article, the authors assess the impact of pain on function of the hand. Pain can be categorized into acute pain, chronic pain, and neuropathic pain. Hand function and objective measurements of hand function are analyzed as well as the impact of different types of pain on each of these areas. PMID:26611383

  11. Functional Task Test (FTT)

    NASA Technical Reports Server (NTRS)

    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

    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.

  12. [Children visual functions development].

    PubMed

    Speeg-Schatz, Claude

    2007-11-30

    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

  13. 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...

  14. Phylogenetic molecular function annotation

    NASA Astrophysics Data System (ADS)

    Engelhardt, Barbara E.; Jordan, Michael I.; Repo, Susanna T.; Brenner, Steven E.

    2009-07-01

    It is now easier to discover thousands of protein sequences in a new microbial genome than it is to biochemically characterize the specific activity of a single protein of unknown function. The molecular functions of protein sequences have typically been predicted using homology-based computational methods, which rely on the principle that homologous proteins share a similar function. However, some protein families include groups of proteins with different molecular functions. A phylogenetic approach for predicting molecular function (sometimes called "phylogenomics") is an effective means to predict protein molecular function. These methods incorporate functional evidence from all members of a family that have functional characterizations using the evolutionary history of the protein family to make robust predictions for the uncharacterized proteins. However, they are often difficult to apply on a genome-wide scale because of the time-consuming step of reconstructing the phylogenies of each protein to be annotated. Our automated approach for function annotation using phylogeny, the SIFTER (Statistical Inference of Function Through Evolutionary Relationships) methodology, uses a statistical graphical model to compute the probabilities of molecular functions for unannotated proteins. Our benchmark tests showed that SIFTER provides accurate functional predictions on various protein families, outperforming other available methods.

  15. An Exceptional Exponential Function

    ERIC Educational Resources Information Center

    Curgus, Branko

    2006-01-01

    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…

  16. Phylogenetic molecular function annotation

    PubMed Central

    Engelhardt, Barbara E; Jordan, Michael I; Repo, Susanna T; Brenner, Steven E

    2010-01-01

    It is now easier to discover thousands of protein sequences in a new microbial genome than it is to biochemically characterize the specific activity of a single protein of unknown function. The molecular functions of protein sequences have typically been predicted using homology-based computational methods, which rely on the principle that homologous proteins share a similar function. However, some protein families include groups of proteins with different molecular functions. A phylogenetic approach for predicting molecular function (sometimes called phylogenomics) is an effective means to predict protein molecular function. These methods incorporate functional evidence from all members of a family that have functional characterizations using the evolutionary history of the protein family to make robust predictions for the uncharacterized proteins. However, they are often difficult to apply on a genome-wide scale because of the time-consuming step of reconstructing the phylogenies of each protein to be annotated. Our automated approach for function annotation using phylogeny, the SIFTER (Statistical Inference of Function Through Evolutionary Relationships) methodology, uses a statistical graphical model to compute the probabilities of molecular functions for unannotated proteins. Our benchmark tests showed that SIFTER provides accurate functional predictions on various protein families, outperforming other available methods. PMID:20664722

  17. Two Functions of Language

    ERIC Educational Resources Information Center

    Feldman, Carol Fleisher

    1977-01-01

    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.…

  18. Cross-functional systems

    NASA Technical Reports Server (NTRS)

    Lee, Mark

    1991-01-01

    Many companies, including Xerox and Texas Instruments, are using cross functional systems to deal with the increasingly complex and competitive business environment. However, few firms within the aerospace industry appear to be aware of the significant benefits that cross functional systems can provide. Those benefits are examined and a flexible methodology is discussed that companies can use to identify and develop cross functional systems that will help improve organizational performance. In addition, some of the managerial issues are addressed that cross functional systems may raise and specific examples are used to explore networking's contributions to cross functional systems.

  19. Holographic tunneling wave function

    NASA Astrophysics Data System (ADS)

    Conti, Gabriele; Hertog, Thomas; van der Woerd, Ellen

    2015-12-01

    The Hartle-Hawking wave function in cosmology can be viewed as a decaying wave function with anti-de Sitter (AdS) boundary conditions. We show that the growing wave function in AdS familiar from Euclidean AdS/CFT is equivalent, semiclassically and up to surface terms, to the tunneling wave function in cosmology. The cosmological measure in the tunneling state is given by the partition function of certain relevant deformations of CFTs on a locally AdS boundary. We compute the partition function of finite constant mass deformations of the O( N ) vector model on the round three sphere and show this qualitatively reproduces the behaviour of the tunneling wave function in Einstein gravity coupled to a positive cosmological constant and a massive scalar. We find the amplitudes of inhomogeneities are not damped in the holographic tunneling state.

  20. On genetic map functions

    SciTech Connect

    Zhao, Hongyu; Speed, T.P.

    1996-04-01

    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.

  1. Functional Explanation and the Function of Explanation

    ERIC Educational Resources Information Center

    Lombrozo, Tania; Carey, Susan

    2006-01-01

    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…

  2. Functional explanation and the function of explanation.

    PubMed

    Lombrozo, Tania; Carey, Susan

    2006-03-01

    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 the theoretical commitments that underlie teleological explanations. With the analysis of [Wright, L. (1976). Teleological Explanations. Berkeley, CA: University of California Press] from philosophy as a point of departure, we examine in Experiment 1 whether teleological explanations are interpreted causally, and confirm that TEs are only accepted when the function invoked in the explanation played a causal role in bringing about what is being explained. However, we also find that playing a causal role is not sufficient for all participants to accept TEs. Experiment 2 shows that this is not because participants fail to appreciate the causal structure of the scenarios used as stimuli. In Experiments 3-5 we show that the additional requirement for TE acceptance is that the process by which the function played a causal role must be general in the sense of conforming to a predictable pattern. These findings motivate a proposal, Explanation for Export, which suggests that a psychological function of explanation is to highlight information likely to subserve future prediction and intervention. We relate our proposal to normative accounts of explanation from philosophy of science, as well as to claims from psychology and artificial intelligence. PMID:15939416

  3. Bayesian Error Estimation Functionals

    NASA Astrophysics Data System (ADS)

    Jacobsen, Karsten W.

    The challenge of approximating the exchange-correlation functional in Density Functional Theory (DFT) has led to the development of numerous different approximations of varying accuracy on different calculated properties. There is therefore a need for reliable estimation of prediction errors within the different approximation schemes to DFT. The Bayesian Error Estimation Functionals (BEEF) have been developed with this in mind. The functionals are constructed by fitting to experimental and high-quality computational databases for molecules and solids including chemisorption and van der Waals systems. This leads to reasonably accurate general-purpose functionals with particual focus on surface science. The fitting procedure involves considerations on how to combine different types of data, and applies Tikhonov regularization and bootstrap cross validation. The methodology has been applied to construct GGA and metaGGA functionals with and without inclusion of long-ranged van der Waals contributions. The error estimation is made possible by the generation of not only a single functional but through the construction of a probability distribution of functionals represented by a functional ensemble. The use of the functional ensemble is illustrated on compound heat of formation and by investigations of the reliability of calculated catalytic ammonia synthesis rates.

  4. Antisymmetric Orbit Functions

    NASA Astrophysics Data System (ADS)

    Klimyk, Anatoliy; Patera, Jiri

    2007-02-01

    In the paper, properties of antisymmetric orbit functions are reviewed and further developed. Antisymmetric orbit functions on the Euclidean space En are antisymmetrized exponential functions. Antisymmetrization is fulfilled by a Weyl group, corresponding to a Coxeter-Dynkin diagram. Properties of such functions are described. These functions are closely related to irreducible characters of a compact semisimple Lie group G of rank n. Up to a sign, values of antisymmetric orbit functions are repeated on copies of the fundamental domain F of the affine Weyl group (determined by the initial Weyl group) in the entire Euclidean space En. Antisymmetric orbit functions are solutions of the corresponding Laplace equation in En, vanishing on the boundary of the fundamental domain F. Antisymmetric orbit functions determine a so-called antisymmetrized Fourier transform which is clo! sely related to expansions of central functions in characters of irreducible representations of the group G. They also determine a transform on a finite set of points of F (the discrete antisymmetric orbit function transform). Symmetric and antisymmetric multivariate exponential, sine and cosine discrete transforms are given.

  5. Function photonic crystals

    NASA Astrophysics Data System (ADS)

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

    2011-07-01

    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 εA and εB. 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.

  6. Relativistic plasma dispersion functions

    NASA Astrophysics Data System (ADS)

    Robinson, P. A.

    1986-05-01

    The known properties of plasma dispersion functions (PDF's) for waves in weakly relativistic, magnetized, thermal plasmas are reviewed and a large number of new results are presented. The PDF's required for the description of waves with small wave number perpendicular to the magnetic field (Dnestrovskii and Shkarofsky functions) are considered in detail; these functions also arise in certain quantum electrodynamical calculations involving strongly magnetized plasmas. Series, asymptotic series, recursion relations, integral forms, derivatives, differential equations, and approximations for these functions are discussed as are their analytic properties and connections with standard transcendental functions. In addition a more general class of PDF's relevant to waves of arbitrary perpendicular wave number is introduced and a range of properties of these functions are derived.

  7. Balance Function Disorders

    NASA Technical Reports Server (NTRS)

    1991-01-01

    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.

  8. Distributed processing; distributed functions?

    PubMed Central

    Fox, Peter T.; Friston, Karl J.

    2016-01-01

    After more than twenty years busily mapping the human brain, what have we learned from neuroimaging? This review (coda) considers this question from the point of view of structure–function relationships and the two cornerstones of functional neuroimaging; functional segregation and integration. Despite remarkable advances and insights into the brain’s functional architecture, the earliest and simplest challenge in human brain mapping remains unresolved: We do not have a principled way to map brain function onto its structure in a way that speaks directly to cognitive neuroscience. Having said this, there are distinct clues about how this might be done: First, there is a growing appreciation of the role of functional integration in the distributed nature of neuronal processing. Second, there is an emerging interest in data-driven cognitive ontologies, i.e., that are internally consistent with functional anatomy. We will focus this review on the growing momentum in the fields of functional connectivity and distributed brain responses and consider this in the light of meta-analyses that use very large data sets to disclose large-scale structure–function mappings in the human brain. PMID:22245638

  9. Perceptual Audio Hashing Functions

    NASA Astrophysics Data System (ADS)

    Özer, Hamza; Sankur, Bülent; Memon, Nasir; Anarım, Emin

    2005-12-01

    Perceptual hash functions provide a tool for fast and reliable identification of content. We present new audio hash functions based on summarization of the time-frequency spectral characteristics of an audio document. The proposed hash functions are based on the periodicity series of the fundamental frequency and on singular-value description of the cepstral frequencies. They are found, on one hand, to perform very satisfactorily in identification and verification tests, and on the other hand, to be very resilient to a large variety of attacks. Moreover, we address the issue of security of hashes and propose a keying technique, and thereby a key-dependent hash function.

  10. CONMIN- CONSTRAINED FUNCTION MINIMIZATION

    NASA Technical Reports Server (NTRS)

    Vanderplaats, G. N.

    1994-01-01

    In many mathematical problems, it is necessary to determine the minimum and maximum of a function of several variables, limited by various linear and nonlinear inequality constraints. It is seldom possible, in practical applications, to solve these problems directly. In most cases, an iterative method must be used to numerically obtain a solution. The CONMIN program was developed to numerically perform the minimization of a multi-variable function subject to a set of inequality constraints. The function need not be a simple analytical equation; it may be any function which can be numerically evaluated. The basic analytic technique used by CONMIN is to minimize the function until one or more of the constraints become active. The minimization process then continues by following the constraint boundaries in a direction such that the value of the function continues to decrease. When a point is reached where no further decrease in the function can be obtained, the process is terminated. Function maximization may be achieved by minimizing the negative of the function. This program is written in FORTRAN IV for batch execution and has been implemented on a CDC 6000 series computer with a central memory requirement of approximately 43K (octal) of 60 bit words. The CONMIN program was originally developed in 1973 and last updated in 1978.

  11. Information barrier functional requirements

    SciTech Connect

    MacArthur, D.; Whiteson, R.

    1998-12-31

    for the purpose of this paper, the authors have used the term functional requirement to indicate a required task rather than the recommended method for accomplishing this task. The creation of effective information barrier technology will proceed as a series of steps: (1) IB conceptual Description; (2) IB Functional Requirements (this document--ongoing); (3) IB hardware and software specification; (4) IB hardware and software construction; and (5) IB implementation. This functional requirements document is not intended to supplant or supersede the conceptual description; rather, these functional requirements are intended to be used along with the earlier description to help generate hardware and software requirements.

  12. Renormalization group functional equations

    SciTech Connect

    Curtright, Thomas L.; Zachos, Cosmas K.

    2011-03-15

    Functional conjugation methods are used to analyze the global structure of various renormalization group trajectories and to gain insight into the interplay between continuous and discrete rescaling. With minimal assumptions, the methods produce continuous flows from step-scaling {sigma} functions and lead to exact functional relations for the local flow {beta} functions, whose solutions may have novel, exotic features, including multiple branches. As a result, fixed points of {sigma} are sometimes not true fixed points under continuous changes in scale and zeroes of {beta} do not necessarily signal fixed points of the flow but instead may only indicate turning points of the trajectories.

  13. Pulmonary Function Tests

    PubMed Central

    Ranu, Harpreet; Wilde, Michael; Madden, Brendan

    2011-01-01

    Pulmonary function tests are valuable investigations in the management of patients with suspected or previously diagnosed respiratory disease. They aid diagnosis, help monitor response to treatment and can guide decisions regarding further treatment and intervention. The interpretation of pulmonary functions tests requires knowledge of respiratory physiology. In this review we describe investigations routinely used and discuss their clinical implications. PMID:22347750

  14. 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...

  15. Logical-function generator

    NASA Technical Reports Server (NTRS)

    Sivertson, W. E., Jr.

    1973-01-01

    Apparatus and technique for generating logical functions and circuits have been developed. They provide aid in designing and constructing hardware to generate logic circuits, by defining circuit connections required to generate these functions. With this method, it is possible quickly and automatically to design logic, while eliminating involved and time-consuming mathematical manipulations.

  16. Functional Magnetic Resonance Imaging

    ERIC Educational Resources Information Center

    Voos, Avery; Pelphrey, Kevin

    2013-01-01

    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

  17. Functional anorectal disorders.

    PubMed

    Bharucha, Adil E; Wald, Arnold; Enck, Paul; Rao, Satish

    2006-04-01

    This report defines criteria for diagnosing functional anorectal disorders (ie, fecal incontinence, anorectal pain, and disorders of defecation). Functional fecal incontinence is defined as the uncontrolled passage of fecal material recurring for > or =3 months in an individual with a developmental age of > or =4 years that is associated with: (1) abnormal functioning of normally innervated and structurally intact muscles, and/or (2) no or minor abnormalities of sphincter structure and/or innervation insufficient to explain fecal incontinence, and/or (3) normal or disordered bowel habits (ie, fecal retention or diarrhea), and/or (4) psychological causes. However, conditions wherein structural and/or neurogenic abnormalities explain the symptom, or are part of a generalized process (eg, diabetic neuropathy) are not included within functional fecal incontinence. Functional fecal incontinence is a common, but underrecognized symptom, which is equally prevalent in men and women, and can often cause considerable distress. The clinical features are useful for guiding diagnostic testing and therapy. Functional anorectal pain syndromes include proctalgia fugax (fleeting pain) and chronic proctalgia; chronic proctalgia may be subdivided into levator ani syndrome and unspecified anorectal pain, which are defined by arbitrary clinical criteria. Functional defecation disorders are characterized by 2 or more symptoms of constipation, with > or =2 of the following features during defecation: impaired evacuation, inappropriate contraction of the pelvic floor muscles, and inadequate propulsive forces. Functional disorders of defecation may be amenable to pelvic floor retraining by biofeedback therapy (such as dyssynergic defecation). PMID:16678564

  18. Functional performance of pyrovalves

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.

    1996-01-01

    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.

  19. Functional Generalized Additive Models

    PubMed Central

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

    2014-01-01

    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 Mller 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

  20. Degenerate Euler zeta function

    NASA Astrophysics Data System (ADS)

    Kim, T.

    2015-10-01

    Recently, T. Kim considered an Euler zeta function which interpolates Euler polynomials at negative integers (see [3]). In this paper, we study the degenerate Euler zeta function which is holomorphic on the complex s-plane and is associated with degenerate Euler polynomials at negative integers.

  1. FLAVONOIDS IN CELL FUNCTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chapters of the new book, Flavonoids in Cell Function, were introduced, and main points pertaining to the diverse biological activities of flavonoids were highlighted. The functions of flavonoids in microbe/plant interactions were discussed, followed by reviews of the use of genetic engineering...

  2. The Planck Radiation Functions.

    ERIC Educational Resources Information Center

    Larsen, Russell D.

    1985-01-01

    Blackbody radiation is used as an example to illustrate that oversimplification in teaching quantum ideas can result in later misunderstanding. Although textbooks give Planck's distribution function in terms of wavelength, there are actually 12 different radiation functions. Some of the more interesting ones are given and discussed. (JN)

  3. Functional Magnetic Resonance Imaging

    ERIC Educational Resources Information Center

    Voos, Avery; Pelphrey, Kevin

    2013-01-01

    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…

  4. FUNCTIONAL FOODS: AN OVERVIEW

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional Foods: Any food, modified food or food ingredient that provides structural, functional or health benefits, thus promoting optimal health, longevity and quality of life, "Food products that provide specific health benefits beyond the traditional nutrients they contain". It is expected th...

  5. Modeling Protein Domain Function

    ERIC Educational Resources Information Center

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

    2007-01-01

    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

  6. Modeling Protein Domain Function

    ERIC Educational Resources Information Center

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

    2007-01-01

    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…

  7. Time Functions as Utilities

    NASA Astrophysics Data System (ADS)

    Minguzzi, E.

    2010-09-01

    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.

  8. Plant functional genomics

    NASA Astrophysics Data System (ADS)

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

    2002-04-01

    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.

  9. Hantush Well Function revisited

    NASA Astrophysics Data System (ADS)

    Veling, E. J. M.; Maas, C.

    2010-11-01

    SummaryIn this paper, we comment on some recent numerical and analytical work to evaluate the Hantush Well Function. We correct an expression found in a Comment by Nadarajah [Nadarajah, S., 2007. A comment on numerical evaluation of Theis and Hantush-Jacob well functions. Journal of Hydrology 338, 152-153] to a paper by Prodanoff et al. [Prodanoff, J.A., Mansur, W.J., Mascarenhas, F.C.B., 2006. Numerical evaluation of Theis and Hantush-Jacob well functions. Journal of Hydrology 318, 173-183]. We subsequently derived another analytic representation based on a generalized hypergeometric function in two variables and from the hydrological literature we cite an analytic representation by Hunt [Hunt, B., 1977. Calculation of the leaky aquifer function. Journal of Hydrology 33, 179-183]. We have implemented both representations and compared the results. Using a convergence accelerator Hunt's representation of Hantush Well Function is efficient and accurate. While checking our implementations we found that Bear's table of the Hantush Well Function [Bear, J., 1979. Hydraulics of Groundwater. McGraw-Hill, New York, Tables 8-6] contains a number of typographical errors that are not present in the original table published by Hantush [Hantush, M.S., 1956. Analysis of data from pumping tests in leaky aquifers. Transactions, American Geophysical Union 37, 702-714]. Finally, we offer a very fast approximation with a maximum relative error of 0.0033 for the parameter range in the table given by Bear.

  10. Functional Performance of Pyrovalves

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.

    1996-01-01

    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.

  11. Penalized Functional Regression

    PubMed Central

    Goldsmith, Jeff; Bobb, Jennifer; Crainiceanu, Ciprian M.; Caffo, Brian; Reich, Daniel

    2011-01-01

    We develop fast fitting methods for generalized functional linear models. The functional predictor is projected onto a large number of smooth eigenvectors and the coefficient function is estimated using penalized spline regression; confidence intervals based on the mixed model framework are obtained. Our method can be applied to many functional data designs including functions measured with and without error, sparsely or densely sampled. The methods also extend to the case of multiple functional predictors or functional predictors with a natural multilevel structure. The approach can be implemented using standard mixed effects software and is computationally fast. The methodology is motivated by a study of white-matter demyelination via diffusion tensor imaging (DTI). The aim of this study is to analyze differences between various cerebral white-matter tract property measurements of multiple sclerosis (MS) patients and controls. While the statistical developments proposed here were motivated by the DTI study, the methodology is designed and presented in generality and is applicable to many other areas of scientific research. An online appendix provides R implementations of all simulations. PMID:22368438

  12. Biomechanics of Cardiac Function.

    PubMed

    Voorhees, Andrew P; Han, Hai-Chao

    2015-10-01

    The heart pumps blood to maintain circulation and ensure the delivery of oxygenated blood to all the organs of the body. Mechanics play a critical role in governing and regulating heart function under both normal and pathological conditions. Biological processes and mechanical stress are coupled together in regulating myocyte function and extracellular matrix structure thus controlling heart function. Here, we offer a brief introduction to the biomechanics of left ventricular function and then summarize recent progress in the study of the effects of mechanical stress on ventricular wall remodeling and cardiac function as well as the effects of wall mechanical properties on cardiac function in normal and dysfunctional hearts. Various mechanical models to determine wall stress and cardiac function in normal and diseased hearts with both systolic and diastolic dysfunction are discussed. The results of these studies have enhanced our understanding of the biomechanical mechanism in the development and remodeling of normal and dysfunctional hearts. Biomechanics provide a tool to understand the mechanism of left ventricular remodeling in diastolic and systolic dysfunction and guidance in designing and developing new treatments. PMID:26426462

  13. The Enzyme Function Initiative

    PubMed Central

    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

    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 EFIs 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

  14. A universal functional object

    NASA Technical Reports Server (NTRS)

    Roth, J. P.

    1972-01-01

    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.

  15. Thyroid function and obesity.

    PubMed

    Longhi, Silvia; Radetti, Giorgio

    2013-01-01

    Nowadays, childhood obesity is one of the biggest health emergencies in the developed countries. Obesity leads to multiple metabolic alterations which increase the risk of developing diabetes and cardiovascular diseases. Thyroid function has been often described as altered in obese children, however, it is not clear whether the altered thyroid function is the cause or the consequence of fat excess. On the other hand, thyroid structure seems also to be affected. Nevertheless, both functional and structural alterations seem to improve after weight loss and therefore no treatment is needed. PMID:23149391

  16. Functionalized expanded porphyrins

    DOEpatents

    Sessler, Jonathan L; Pantos, Patricia J

    2013-11-12

    Disclosed are functionalized expanded porphyrins that can be used as spectrometric sensors for high-valent actinide cations. The disclosed functionalized expanded porphyrins have the advantage over unfunctionalized systems in that they can be immobilized via covalent attachment to a solid support comprising an inorganic or organic polymer or other common substrates. Substrates comprising the disclosed functionalized expanded porphyrins are also disclosed. Further, disclosed are methods of making the disclosed compounds (immobilized and free), methods of using them as sensors to detect high valent actinides, devices that comprise the disclosed compounds, and kits.

  17. Functional Group Analysis.

    ERIC Educational Resources Information Center

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

    1984-01-01

    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,

  18. Kidney function tests

    MedlinePlus

    Oh MS. Evaluation of renal function, water, electrolytes and acid-base balance. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 22nd ed. Philadelphia, PA: Elsevier Saunders; 2011:chap ...

  19. Pulmonary function tests

    MedlinePlus

    ... measured to estimate the lung volume. To measure diffusion capacity , you breathe a harmless gas, called a ... on your report after pulmonary function tests include: Diffusion capacity to carbon monoxide (DLCO) Expiratory reserve volume ( ...

  20. Hepatic (Liver) Function Panel

    MedlinePlus

    ... by the liver and attached to other chemicals). Albumin and total protein. Protein is needed to build ... so protein levels decrease. Liver function tests measure albumin specifically (the major blood protein produced by the ...

  1. Thyroid function tests

    MedlinePlus

    ... common thyroid function tests are: Total, or free T4 (the main thyroid hormone in your blood) TSH ( ... pituitary gland that stimulates the thyroid to produce T4) T3 (also included sometimes) Other thyroid tests include: ...

  2. Bioprinting: Functional droplet networks

    NASA Astrophysics Data System (ADS)

    Durmus, Naside Gozde; Tasoglu, Savas; Demirci, Utkan

    2013-06-01

    Tissue-mimicking printed networks of droplets separated by lipid bilayers that can be functionalized with membrane proteins are able to spontaneously fold and transmit electrical currents along predefined paths.

  3. Functional Group Interconversions

    ERIC Educational Resources Information Center

    Yeadon, A.

    1974-01-01

    Describes some functional group interconversions that can be carried out on a small scale. The reactions are examples of transformations found in A-level, ONC and HNC courses for British chemistry students. (Author/GS)

  4. Congenital platelet function defects

    MedlinePlus

    Platelet storage pool disorder; Glanzmann's thrombasthenia; Bernard-Soulier syndrome; Platelet function defects - congenital ... disorder may also cause severe bleeding. Platelet storage pool disorder (also called platelet secretion disorder) occurs when ...

  5. Testosterone and Sexual Function.

    PubMed

    Gannon, John R; Walsh, Thomas J

    2016-05-01

    Testosterone and sexual function are related. Current evidence suggests that testosterone replacement therapy (TRT) may improve sexual dysfunction. Sexual dysfunction in men who are hypogonadal, mixed, or eugonadal have all been examined through numerous studies. The most recent large analysis showed an overall improvement in sexual function outcomes in men treated with TRT. This improvement is difficult to measure and seems to differ based on the baseline hormonal status of the patient at the beginning of treatment. PMID:27132579

  6. Polarized Antenna Splitting Functions

    SciTech Connect

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

    2009-10-17

    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.

  7. Functional Molecular Ecological Networks

    PubMed Central

    Zhou, Jizhong; Deng, Ye; Luo, Feng; He, Zhili; Tu, Qichao; Zhi, Xiaoyang

    2010-01-01

    Biodiversity and its responses to environmental changes are central issues in ecology and for society. Almost all microbial biodiversity research focuses on “species” richness and abundance but not on their interactions. Although a network approach is powerful in describing ecological interactions among species, defining the network structure in a microbial community is a great challenge. Also, although the stimulating effects of elevated CO2 (eCO2) on plant growth and primary productivity are well established, its influences on belowground microbial communities, especially microbial interactions, are poorly understood. Here, a random matrix theory (RMT)-based conceptual framework for identifying functional molecular ecological networks was developed with the high-throughput functional gene array hybridization data of soil microbial communities in a long-term grassland FACE (free air, CO2 enrichment) experiment. Our results indicate that RMT is powerful in identifying functional molecular ecological networks in microbial communities. Both functional molecular ecological networks under eCO2 and ambient CO2 (aCO2) possessed the general characteristics of complex systems such as scale free, small world, modular, and hierarchical. However, the topological structures of the functional molecular ecological networks are distinctly different between eCO2 and aCO2, at the levels of the entire communities, individual functional gene categories/groups, and functional genes/sequences, suggesting that eCO2 dramatically altered the network interactions among different microbial functional genes/populations. Such a shift in network structure is also significantly correlated with soil geochemical variables. In short, elucidating network interactions in microbial communities and their responses to environmental changes is fundamentally important for research in microbial ecology, systems microbiology, and global change. PMID:20941329

  8. Structure function monitor

    DOEpatents

    McGraw, John T.; Zimmer, Peter C.; Ackermann, Mark R.

    2012-01-24

    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.

  9. Center for Functional Nanomaterials

    ScienceCinema

    BNL

    2009-09-01

    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.

  10. Center for Functional Nanomaterials

    SciTech Connect

    BNL

    2008-08-12

    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.

  11. A Function Machine

    ERIC Educational Resources Information Center

    Hewitt, Dave

    2008-01-01

    In this article, the author describes a lesson he observed involving a function machine. This function machine was a box with a slot at the top of one side and a large cut-out hole at the bottom of the opposite side. A card with a number written on it (the input) was pushed into the slot and the teacher put their hand through the hole of the other…

  12. Adaptive transfer functions

    SciTech Connect

    Goulding, J.R. )

    1991-01-01

    This paper details the approach and methodology used to build adaptive transfer functions in a feed-forward Back-Propagation neural network, and provides insight into the structure dependent properties of using non-scaled analog inputs. The results of using adaptive transfer functions are shown to outperform conventional architectures in the implementation of a mechanical power transmission gearbox design expert system knowledge base. 4 refs., 4 figs., 1 tab.

  13. Functional Task Test: Data Review

    NASA Technical Reports Server (NTRS)

    Cromwell, Ronita

    2014-01-01

    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?

  14. Platelet Function Tests.

    PubMed

    Lordkipanidzé, Marie

    2016-04-01

    Traditionally developed for diagnosis of bleeding disorders, platelet function assays have become increasingly used in basic research on platelet physiology, in phenotype-genotype associations in bleeding disorders, in drug development as surrogate endpoints of efficacy of new antiplatelet therapy, and to an extent, in the monitoring of antiplatelet therapy in clinical practice to predict thrombotic and bleeding risk. A multiplicity of platelet function assays is available to measure the level of platelet activity in various settings. These include assays that are restricted to a specialized laboratory as well as point-of-care instruments meant to investigate platelet function at patient bedside. Unlike tests that determine a defined quantity or measurement of a clinical biomarker (e.g., cholesterol or blood pressure), platelet function testing assesses the dynamics of living cells, which immediately presents a series of unique problems to any laboratory or clinic. This article presents currently used platelet function assays and discusses important variables to take into account when performing these assays, including preanalytical issues and difficulties in interpreting platelet function test results. PMID:26926583

  15. Functional peptides by design

    NASA Astrophysics Data System (ADS)

    Kretsinger, Juliana K.

    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.

  16. Human fetal thyroid function.

    PubMed

    Polak, Michel

    2014-01-01

    The early steps of thyroid development that lead to its function in the human fetus and subsequently the further maturation that allows the human fetus to secrete thyroxine (T4) in a significant amount are reviewed here. We underline the importance of the transfer of T4 from the pregnant woman to her fetus, which contributes at all stages of the pregnancy to fetal thyroid function and development. In the first trimester of pregnancy, the temporal and structural correlation of thyroid hormone synthesis with folliculogenesis supported the concept that structural and functional maturations are closely related. Human thyroid terminal differentiation follows a precisely timed gene expression program. The crucial role of the sodium/iodine symporter for the onset of thyroid function in the human fetus is shown. Fetal T4 is detected by the eleventh week of gestation and progressively increases throughout. The pattern of thyroid hormones and thyroid-stimulating hormone levels in the course of pregnancy is given from fetal blood sampling data, and the mechanisms governing this maturation in the human fetus are discussed. Finally an example of primary human fetal thyroid dysfunction, such as in Down syndrome, is given. The understanding of the physiology of the human fetal thyroid function is the basis for fetal medicine in the field of thyroidology. PMID:25231441

  17. Space race functional responses.

    PubMed

    Sjödin, Henrik; Brännström, Åke; Englund, Göran

    2015-02-22

    We derive functional responses under the assumption that predators and prey are engaged in a space race in which prey avoid patches with many predators and predators avoid patches with few or no prey. The resulting functional response models have a simple structure and include functions describing how the emigration of prey and predators depend on interspecific densities. As such, they provide a link between dispersal behaviours and community dynamics. The derived functional response is general but is here modelled in accordance with empirically documented emigration responses. We find that the prey emigration response to predators has stabilizing effects similar to that of the DeAngelis-Beddington functional response, and that the predator emigration response to prey has destabilizing effects similar to that of the Holling type II response. A stability criterion describing the net effect of the two emigration responses on a Lotka-Volterra predator-prey system is presented. The winner of the space race (i.e. whether predators or prey are favoured) is determined by the relationship between the slopes of the species' emigration responses. It is predicted that predators win the space race in poor habitats, where predator and prey densities are low, and that prey are more successful in richer habitats. PMID:25589602

  18. Space race functional responses

    PubMed Central

    Sjödin, Henrik; Brännström, Åke; Englund, Göran

    2015-01-01

    We derive functional responses under the assumption that predators and prey are engaged in a space race in which prey avoid patches with many predators and predators avoid patches with few or no prey. The resulting functional response models have a simple structure and include functions describing how the emigration of prey and predators depend on interspecific densities. As such, they provide a link between dispersal behaviours and community dynamics. The derived functional response is general but is here modelled in accordance with empirically documented emigration responses. We find that the prey emigration response to predators has stabilizing effects similar to that of the DeAngelis–Beddington functional response, and that the predator emigration response to prey has destabilizing effects similar to that of the Holling type II response. A stability criterion describing the net effect of the two emigration responses on a Lotka–Volterra predator–prey system is presented. The winner of the space race (i.e. whether predators or prey are favoured) is determined by the relationship between the slopes of the species' emigration responses. It is predicted that predators win the space race in poor habitats, where predator and prey densities are low, and that prey are more successful in richer habitats. PMID:25589602

  19. The Tensor Distribution Function

    PubMed Central

    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

    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

  20. SCARF SOCIAL FUNCTIONING INDEX

    PubMed Central

    Padmavathi, R.; Thara, R.; Srinivasan, Latha; Kumar, Shuba

    1995-01-01

    Several instruments measuring social functioning have been developed in the last four decades, as a result of the increasing interest in community care of the chronic mentally ill. SCARF Social Functioning Index (SSFI) was developed to meet the pressing need for an instrument which was easy to administer and which could be used by all mental health professionals. The SSFI comprises four main sections: self concern, occupational role, role in the family and other social roles. Each section has several subsections covering different areas of social functioning. Validity and reliability have been established for a group of normals, patients suffering from schizophrenia and from Hansen's disease. Internal consistencies of these factors were high Factor analysis derived four main factors, which included nearly all items of the SSFI. This paper reports on the development and standardization of the instrument. PMID:21743742

  1. Velopharyngeal function and dysfunction.

    PubMed

    Jones, D L

    1991-01-01

    The concepts regarding velopharyngeal function, the production of disordered nasalization, and the management of velopharyngeal dysfunction can be summarized as follows: 1. Although the function of the velopharyngeal mechanism is critical to the control of oral-nasal balance, the configuration and function of the speech articulatory system as a whole will determine the degree of nasalized speech that is produced. 2. Velopharyngeal dysfunction can be related to one or a combination of structural and motor limitations within the velopharyngeal mechanism. 3. There are two perceptual manifestations of velopharyngeal dysfunction. One is acoustic (nasality); the other is aerodynamic (nasal emission). For any given speaker, it is possible to hear both, and it is possible to hear one and not the other. 4. Velopharyngeal dysfunction can be treated in a variety of ways. The method of treatment should be determined by the structural characteristics of the velopharyngeal mechanism and the speech-motor abilities of the patient. PMID:1844858

  2. Diaphragmatic function during immersion.

    PubMed

    Minh, V D; Dolan, G F; Linaweaver, P G; Friedman, P J; Konopka, R G; Brach, B B

    1977-08-01

    Diaphragmatic function during immersion to midneck level was studied in upright mongrel dogs, using constant electrophrenic stimulation. Effectiveness of diaphragmatic contraction was analyzed in terms of inspired volume (VT) (with airways open), and change in intrathoracic pressure (Pmus) (with the respiratory system occluded). Hydrostatic compression of the immersed body decreased functional residual capacity (FRC) to 55% base-line value (FRCO), resulting in a 2.8-fold increase in Pmus. In spite of this Pmus increase, VT often decreased during immersion, averaging only 83% VTO (base-line value in air). Hence, immersion was associated with a marked stiffening of the respiratory system. The Pmus increase during immersion persisted after restoration of FRC to FRCO, and was related to diaphragmatic length being greater in water than in air under condition of iso-lung volume. In all, there were three factors affecting diaphragmatic function during immersion: FRC reduction, change in thoracic configuration, and stiffening of the respiratory system. PMID:893286

  3. Tendon functional extracellular matrix.

    PubMed

    Screen, Hazel R C; Berk, David E; Kadler, Karl E; Ramirez, Francesco; Young, Marian F

    2015-06-01

    This article is one of a series, summarizing views expressed at the Orthopaedic Research Society New Frontiers in Tendon Research Conference. This particular article reviews the three workshops held under the "Functional Extracellular Matrix" stream. The workshops focused on the roles of the tendon extracellular matrix, such as performing the mechanical functions of tendon, creating the local cell environment, and providing cellular cues. Tendon is a complex network of matrix and cells, and its biological functions are influenced by widely varying extrinsic and intrinsic factors such as age, nutrition, exercise levels, and biomechanics. Consequently, tendon adapts dynamically during development, aging, and injury. The workshop discussions identified research directions associated with understanding cell-matrix interactions to be of prime importance for developing novel strategies to target tendon healing or repair. PMID:25640030

  4. Protein Functionalized Nanodiamond Arrays

    PubMed Central

    2010-01-01

    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

  5. Algal functional annotation tool

    SciTech Connect

    Lopez, D.; Casero, D.; Cokus, S. J.; Merchant, S. S.; Pellegrini, M.

    2012-07-01

    The Algal Functional Annotation Tool is a web-based comprehensive analysis suite integrating annotation data from several pathway, ontology, and protein family databases. The current version provides annotation for the model alga Chlamydomonas reinhardtii, and in the future will include additional genomes. The site allows users to interpret large gene lists by identifying associated functional terms, and their enrichment. Additionally, expression data for several experimental conditions were compiled and analyzed to provide an expression-based enrichment search. A tool to search for functionally-related genes based on gene expression across these conditions is also provided. Other features include dynamic visualization of genes on KEGG pathway maps and batch gene identifier conversion.

  6. Tensor distribution function

    NASA Astrophysics Data System (ADS)

    Leow, Alex D.; Zhu, Siwei

    2008-03-01

    Diffusion weighted MR 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-sensitizing gradients along a minimum of 6 directions, second-order tensors (represetnted by 3-by-3 positive definiite matrices) can be computed to model dominant diffusion processes. However, it has been shown that conventional DTI is not sufficient to resolve more complicated white matter configurations, e.g. crossing fiber tracts. More recently, High Angular Resolution Diffusion Imaging (HARDI) seeks to address this issue by employing more than 6 gradient directions. To account for fiber crossing when analyzing HARDI data, several methodologies have been introduced. For example, q-ball imaging was proposed to approximate Orientation Diffusion Function (ODF). Similarly, the PAS method seeks to reslove the angular structure of displacement probability functions using the maximum entropy principle. Alternatively, deconvolution methods extract multiple fiber tracts by computing fiber orientations using a pre-specified single fiber response function. In this study, we introduce Tensor Distribution Function (TDF), a probability function defined on the space of symmetric and positive definite matrices. Using calculus of variations, we solve for 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, ODF can easily be computed by analytical integration of the resulting displacement probability function. Moreover, principle fiber directions can also be directly derived from the TDF.

  7. Adaptive multiconfigurational wave functions

    SciTech Connect

    Evangelista, Francesco A.

    2014-03-28

    A method is suggested to build simple multiconfigurational wave functions specified uniquely by an energy cutoff Λ. These are constructed from a model space containing determinants with energy relative to that of the most stable determinant no greater than Λ. The resulting Λ-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 (Λ+SD-CI), which is based on a small Λ-CI reference and adds a selection of all the singly and doubly excited determinants generated from it. We report two heuristic algorithms to build Λ-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 Λ-CI and Λ+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 Λ-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 Λ-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.

  8. Functional neuroimaging of migraine.

    PubMed

    Denuelle, M; Fabre, N

    2013-05-01

    This review summarizes the history of migraine imaging and key findings of studies on functional neuroimaging in migraine and describes how these data have changed our view of the disorder. Functional neuroimaging during migraine attacks and also interictally has initiated the description of "the migraine brain". These studies have led to the demonstration of cortical spreading depression in migraine with aura, the crucial role for the brainstem during migraine attacks, and cortical hypersensitivity in migraineurs modulated by the trigeminal pathway, explaining sensory sensitization such as photophobia and osmophobia. PMID:23602115

  9. Algal functional annotation tool

    Energy Science and Technology Software Center (ESTSC)

    2012-07-12

    Abstract BACKGROUND: Progress in genome sequencing is proceeding at an exponential pace, and several new algal genomes are becoming available every year. One of the challenges facing the community is the association of protein sequences encoded in the genomes with biological function. While most genome assembly projects generate annotations for predicted protein sequences, they are usually limited and integrate functional terms from a limited number of databases. Another challenge is the use of annotations tomore » interpret large lists of 'interesting' genes generated by genome-scale datasets. Previously, these gene lists had to be analyzed across several independent biological databases, often on a gene-by-gene basis. In contrast, several annotation databases, such as DAVID, integrate data from multiple functional databases and reveal underlying biological themes of large gene lists. While several such databases have been constructed for animals, none is currently available for the study of algae. Due to renewed interest in algae as potential sources of biofuels and the emergence of multiple algal genome sequences, a significant need has arisen for such a database to process the growing compendiums of algal genomic data. DESCRIPTION: The Algal Functional Annotation Tool is a web-based comprehensive analysis suite integrating annotation data from several pathway, ontology, and protein family databases. The current version provides annotation for the model alga Chlamydomonas reinhardtii, and in the future will include additional genomes. The site allows users to interpret large gene lists by identifying associated functional terms, and their enrichment. Additionally, expression data for several experimental conditions were compiled and analyzed to provide an expression-based enrichment search. A tool to search for functionally-related genes based on gene expression across these conditions is also provided. Other features include dynamic visualization of genes on KEGG pathway maps and batch gene identifier conversion. CONCLUSIONS: The Algal Functional Annotation Tool aims to provide an integrated data-mining environment for algal genomics by combining data from multiple annotation databases into a centralized tool. This site is designed to expedite the process of functional annotation and the interpretation of gene lists, such as those derived from high-throughput RNA-seq experiments. The tool is publicly available at http://pathways.mcdb.ucla.edu.« less

  10. Functionalization of Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    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.

  11. Functionalization of carbon nanotubes

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    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.

  12. Algal functional annotation tool

    SciTech Connect

    2012-07-12

    Abstract BACKGROUND: Progress in genome sequencing is proceeding at an exponential pace, and several new algal genomes are becoming available every year. One of the challenges facing the community is the association of protein sequences encoded in the genomes with biological function. While most genome assembly projects generate annotations for predicted protein sequences, they are usually limited and integrate functional terms from a limited number of databases. Another challenge is the use of annotations to interpret large lists of 'interesting' genes generated by genome-scale datasets. Previously, these gene lists had to be analyzed across several independent biological databases, often on a gene-by-gene basis. In contrast, several annotation databases, such as DAVID, integrate data from multiple functional databases and reveal underlying biological themes of large gene lists. While several such databases have been constructed for animals, none is currently available for the study of algae. Due to renewed interest in algae as potential sources of biofuels and the emergence of multiple algal genome sequences, a significant need has arisen for such a database to process the growing compendiums of algal genomic data. DESCRIPTION: The Algal Functional Annotation Tool is a web-based comprehensive analysis suite integrating annotation data from several pathway, ontology, and protein family databases. The current version provides annotation for the model alga Chlamydomonas reinhardtii, and in the future will include additional genomes. The site allows users to interpret large gene lists by identifying associated functional terms, and their enrichment. Additionally, expression data for several experimental conditions were compiled and analyzed to provide an expression-based enrichment search. A tool to search for functionally-related genes based on gene expression across these conditions is also provided. Other features include dynamic visualization of genes on KEGG pathway maps and batch gene identifier conversion. CONCLUSIONS: The Algal Functional Annotation Tool aims to provide an integrated data-mining environment for algal genomics by combining data from multiple annotation databases into a centralized tool. This site is designed to expedite the process of functional annotation and the interpretation of gene lists, such as those derived from high-throughput RNA-seq experiments. The tool is publicly available at http://pathways.mcdb.ucla.edu.

  13. Design of Functional Metalloproteins

    PubMed Central

    Lu, Yi; Yeung, Natasha; Sieracki, Nathan; Marshall, Nicholas M.

    2009-01-01

    Metalloproteins catalyze some of the most difficult and yet important functions in Nature, such as photosynthesis and water oxidation. An ultimate test of our knowledge of how metalloproteins work is by designing novel metalloproteins. Such design can not only reveal hidden structural features that may be missing from studies of native metalloproteins and their variants, but also result in new metalloenzymes for biotechnological and pharmaceutical applications. While it is much more challenging to design metalloproteins than non-metalloproteins, much progress has been made in this area, particularly toward functional design, thanks to recent progress in areas such as computational and structural biology. PMID:19675646

  14. Peroxisome Biogenesis and Function

    PubMed Central

    Kaur, Navneet; Reumann, Sigrun; Hu, Jianping

    2009-01-01

    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

  15. Clocks and cardiovascular function

    PubMed Central

    McLoughlin, Sarah C.; Haines, Philip; FitzGerald, Garret A.

    2016-01-01

    Circadian clocks in central and peripheral tissues enable the temporal synchronization and organization of molecular and physiological processes of rhythmic animals, allowing optimum functioning of cells and organisms at the most appropriate time of day. Disruption of circadian rhythms, from external or internal forces, leads to widespread biological disruption and is postulated to underlie many human conditions, such as the incidence and timing of cardiovascular disease. Here, we describe in vivo and in vitro methodology relevant to studying the role of circadian rhythms in cardiovascular function and dysfunction PMID:25707279

  16. GADRAS Detector Response Function.

    SciTech Connect

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

    2014-11-01

    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.

  17. Functional Hybrid Materials

    NASA Astrophysics Data System (ADS)

    Gómez-Romero, Pedro; Sanchez, Clément

    2004-04-01

    Functional Hybrid Materials consist of both organic and inorganic components, assembled for the purpose of generating desirable properties and functionalities. The aim is twofold: to bring out or enhance advantageous chemical, electrochemical, magnetic or electronic characteristics and at the same time to reduce or wholly suppress undesirable properties or effects. Another target is the creation of entirely new material behavior. The vast number of hybrid material components available has opened up a wide and diversified field of fascinating research. In this book, a team of highly renowned experts gives an in-depth overview, illustrating the superiority of well-designed hybrid materials and their potential applications.

  18. Transfer function matrix

    NASA Technical Reports Server (NTRS)

    Seraji, H.

    1987-01-01

    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.

  19. Functional Communication Training

    ERIC Educational Resources Information Center

    Durand, V. Mark; Moskowitz, Lauren

    2015-01-01

    Thirty years ago, the first experimental demonstration was published showing that educators could improve significant challenging behavior in children with disabilities by replacing these behaviors with forms of communication that served the same purpose, a procedure called functional communication training (FCT). Since the publication of that…

  20. Multisensory Executive Functioning

    ERIC Educational Resources Information Center

    Hunt, Amelia R.; Kingstone, Alan

    2004-01-01

    To better understand the prefrontal circuitry that putatively supports executive functions, such as those involved in switching tasks, we asked whether a current task set is open equally to receiving information from any sensory modality or if it is to some degree modality-specific. Subjects were presented with a sequence of digits to be…

  1. Stimulating the Collegiate Function.

    ERIC Educational Resources Information Center

    Brawer, Florence B.

    This paper examines recent efforts by community college educators to enhance the liberal arts in a curriculum which is increasingly dominated by career, compensatory, and community education programs. The paper first notes the decline of the transfer function at today's community colleges and argues that the liberal arts, if they are to survive,…

  2. Iridescence: a functional perspective

    PubMed Central

    Doucet, Stéphanie M.; Meadows, Melissa G.

    2009-01-01

    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

  3. Functional Extended Redundancy Analysis

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  4. Choreographing Patterns and Functions

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  5. Objectification and Semiotic Function

    ERIC Educational Resources Information Center

    Santi, George

    2011-01-01

    The objective of this paper is to study students' difficulties when they have to ascribe the same meaning to different representations of the same mathematical object. We address two theoretical tools that are at the core of Radford's cultural semiotic and Godino's onto-semiotic approaches: objectification and the semiotic function. The analysis…

  6. Linear Classification Functions.

    ERIC Educational Resources Information Center

    Huberty, Carl J.; Smith, Jerry D.

    Linear classification functions (LCFs) arise in a predictive discriminant analysis for the purpose of classifying experimental units into criterion groups. The relative contribution of the response variables to classification accuracy may be based on LCF-variable correlations for each group. It is proved that, if the raw response measures are…

  7. Conjugate flow action functionals

    SciTech Connect

    Venturi, Daniele

    2013-11-15

    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 Gteaux 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.

  8. Empirical microeconomics action functionals

    NASA Astrophysics Data System (ADS)

    Baaquie, Belal E.; Du, Xin; Tanputraman, Winson

    2015-06-01

    A statistical generalization of microeconomics has been made in Baaquie (2013), where the market price of every traded commodity, at each instant of time, is considered to be an independent random variable. The dynamics of commodity market prices is modeled by an action functional-and the focus of this paper is to empirically determine the action functionals for different commodities. The correlation functions of the model are defined using a Feynman path integral. The model is calibrated using the unequal time correlation of the market commodity prices as well as their cubic and quartic moments using a perturbation expansion. The consistency of the perturbation expansion is verified by a numerical evaluation of the path integral. Nine commodities drawn from the energy, metal and grain sectors are studied and their market behavior is described by the model to an accuracy of over 90% using only six parameters. The paper empirically establishes the existence of the action functional for commodity prices that was postulated to exist in Baaquie (2013).

  9. Multisensory Executive Functioning

    ERIC Educational Resources Information Center

    Hunt, Amelia R.; Kingstone, Alan

    2004-01-01

    To better understand the prefrontal circuitry that putatively supports executive functions, such as those involved in switching tasks, we asked whether a current task set is open equally to receiving information from any sensory modality or if it is to some degree modality-specific. Subjects were presented with a sequence of digits to be

  10. Chromosome structure and function

    SciTech Connect

    Risley, M.S.

    1986-01-01

    This book presents topics in chromosome structure and function. Topics covered include: the structure of interphase chromatin; chromatin structure, gene expression and differentiation; organization of mitotic chromosomes; organization of meiotic chromosomes and synaptonimal complexes; the lampbrush chromsome of animal oocytes; dosage compensation in mammals: x chromosome inactivation; and polytene chromosomes.

  11. Functional Extended Redundancy Analysis

    ERIC Educational Resources Information Center

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

    2012-01-01

    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

  12. Process for functionalizing alkanes

    DOEpatents

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

    1988-05-24

    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

  13. Split Brain Functioning.

    ERIC Educational Resources Information Center

    Cassel, Russell N.

    1978-01-01

    Summarizing recent research, this article defines the functions performed by the left and right sides of the human brain. Attention is given to the right side, or the nondominant side, of the brain and its potential in terms of perception of the environment, music, art, geometry, and the aesthetics. (JC)

  14. Gluing Nekrasov Partition Functions

    NASA Astrophysics Data System (ADS)

    Qiu, Jian; Tizzano, Luigi; Winding, Jacob; Zabzine, Maxim

    2015-07-01

    In this paper we summarise the localisation calculation of 5D super Yang-Mills on simply connected toric Sasaki-Einstein (SE) manifolds. We show how various aspects of the computation, including the equivariant index, the asymptotic behaviour and the factorisation property are governed by the combinatorial data of the toric geometry. We prove that the perturbative partition function on a simply connected SE manifold corresponding to an n-gon toric diagram factorises to n copies of perturbative part (zero instanton sector) of the Nekrasov partition function. This leads us to conjecture a prescription for the computation of the complete partition function, by gluing n copies of the full Nekrasov partition functions. This work is a generalisation of some earlier computation carried out on Y p, q manifolds, whose moment map cone has a quadrangle base and our result is valid for manifolds whose moment map cones have pentagon base, hexagon base, etc. The algorithm we used for dealing with general cones may also be of independent interest.

  15. COPPER AND BRAIN FUNCTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing evidence shows that brain development and function are impaired when the brain is deprived of copper either through dietary copper deficiency or through genetic defects in copper transport. A number of copper-dependent enzymes whose activities are lowered by copper deprivation form the ba...

  16. Platelet Function Tests

    MedlinePlus

    ... services. Advertising & Sponsorship: Policy | Opportunities PLEASE NOTE: Your web browser does not have JavaScript enabled. Unless you enable Javascript , your ability to navigate and access the features of this website will be ... Platelet Function Tests Share this page: Was this page helpful? Also ...

  17. Conjugate flow action functionals

    SciTech Connect

    Venturi, Daniele

    2013-11-15

    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.

  18. Objectification and Semiotic Function

    ERIC Educational Resources Information Center

    Santi, George

    2011-01-01

    The objective of this paper is to study students' difficulties when they have to ascribe the same meaning to different representations of the same mathematical object. We address two theoretical tools that are at the core of Radford's cultural semiotic and Godino's onto-semiotic approaches: objectification and the semiotic function. The analysis

  19. Functional Group Analysis.

    ERIC Educational Resources Information Center

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

    1984-01-01

    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,…

  20. Muscle function loss

    MedlinePlus

    ... nerve injury, or brain damage ( stroke or other brain injury) The loss of muscle function after these types of events can be severe. Often it will not completely return, even with treatment. Paralysis can be temporary or permanent. It can affect ...

  1. Engineering Living Functional Materials

    PubMed Central

    2016-01-01

    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

  2. Partition density functional theory

    NASA Astrophysics Data System (ADS)

    Nafziger, Jonathan

    Partition density functional theory (PDFT) is a method for dividing a molecular electronic structure calculation into fragment calculations. The molecular density and energy corresponding to Kohn Sham density-functional theory (KS-DFT) may be exactly recovered from these fragments. Each fragment acts as an isolated system except for the influence of a global one-body 'partition' potential which deforms the fragment densities. In this work, the developments of PDFT are put into the context of other fragment-based density functional methods. We developed three numerical implementations of PDFT: One within the NWChem computational chemistry package using basis sets, and the other two developed from scratch using real-space grids. It is shown that all three of these programs can exactly reproduce a KS-DFT calculation via fragment calculations. The first of our in-house codes handles non-interacting electrons in arbitrary one-dimensional potentials with any number of fragments. This code is used to explore how the exact partition potential changes for different partitionings of the same system and also to study features which determine which systems yield non-integer PDFT occupations and which systems are locked into integer PDFT occupations. The second in-house code, CADMium, performs real-space calculations of diatomic molecules. Features of the exact partition potential are studied for a variety of cases and an analytical formula determining singularities in the partition potential is derived. We introduce an approximation for the non-additive kinetic energy and show how this quantity can be computed exactly. Finally a PDFT functional is developed to address the issues of static correlation and delocalization errors in approximations within DFT. The functional is applied to the dissociation of H2 + and H2.

  3. Pulmonary function in space

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

    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.

  4. Engineering living functional materials.

    PubMed

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

    2015-01-16

    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

  5. Functional Performance Evaluation

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  6. Marrying Form and Function: A Place for Grammar and Total Target Language in the Secondary Modern Foreign Languages Classroom. Occasional Paper.

    ERIC Educational Resources Information Center

    Hogg, Ivy

    This paper examines the possible role of grammar throughout Key Stages 3 and 4 in the modern language curriculum where communication is the central tenet. It also discusses how total or virtually total use of target language (German) in the classroom can help deal with the dichotomy of grammar versus communication and bring about an integrated…

  7. Pseudoproteases: mechanisms and function.

    PubMed

    Reynolds, Simone L; Fischer, Katja

    2015-05-15

    Catalytically inactive enzymes (also known as pseudoproteases, protease homologues or paralogues, non-peptidase homologues, non-enzymes and pseudoenzymes) have traditionally been hypothesized to act as regulators of their active homologues. However, those that have been characterized demonstrate that inactive enzymes have an extensive and expanding role in biological processes, including regulation, inhibition and immune modulation. With the emergence of each new genome, more inactive enzymes are being identified, and their abundance and potential as therapeutic targets has been realized. In the light of the growing interest in this emerging field the present review focuses on the classification, structure, function and mechanism of inactive enzymes. Examples of how inactivity is defined, how this is reflected in the structure, functions of inactive enzymes in biological processes and their mode of action are discussed. PMID:25940733

  8. Functionalization of Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    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.

  9. Nuclear Parton Distribution Functions

    SciTech Connect

    I. Schienbein, J.Y. Yu, C. Keppel, J.G. Morfin, F. Olness, J.F. Owens

    2009-06-01

    We study nuclear effects of charged current deep inelastic neutrino-iron scattering in the framework of a {chi}{sup 2} analysis of parton distribution functions (PDFs). We extract a set of iron PDFs which are used to compute x{sub Bj}-dependent and Q{sup 2}-dependent nuclear correction factors for iron structure functions which are required in global analyses of free nucleon PDFs. We compare our results with nuclear correction factors from neutrino-nucleus scattering models and correction factors for charged-lepton--iron scattering. We find that, except for very high x{sub Bj}, our correction factors differ in both shape and magnitude from the correction factors of the models and charged-lepton scattering.

  10. Functional studies using NMR

    SciTech Connect

    McCready, V.R.; Leach, M.; Ell, P.J.

    1987-01-01

    This volume is based on a series of lectures delivered at a one-day teaching symposium on functional and metabolic aspects of NMR measurements held at the Middlesex Hospital Medical School on 1st September 1985 as a part of the European Nuclear Medicine Society Congress. Currently the major emphasis in medical NMR in vivo is on its potential to image and display abnormalities in conventional radiological images, providing increased contrast between normal and abnormal tissue, improved definition of vasculature, and possibly an increased potential for differential diagnosis. Although these areas are undeniably of major importance, it is probable that NMR will continue to complement conventional measurement methods. The major potential benefits to be derived from in vivo NMR measurements are likely to arise from its use as an instrument for functional and metabolic studies in both clinical research and in the everyday management of patients. It is to this area that this volume is directed.

  11. Sleep and emotional functions.

    PubMed

    Perogamvros, Lampros; Schwartz, Sophie

    2015-01-01

    In this chapter, we review studies investigating the role of sleep in emotional functions. In particular, evidence has recently accumulated to show that brain regions involved in the processing of emotional and reward-related information are activated during sleep. We suggest that such activation of emotional and reward systems during sleep underlies the reprocessing and consolidation of memories with a high affective and motivational relevance for the organism. We also propose that these mechanisms occurring during sleep promote adapted cognitive and emotional responses in the waking state, including overnight performance improvement, creativity, and sexual functions. Activation across emotional-limbic circuits during sleep also appears to promote emotional maturation and the emergence of consciousness in the developing brain. PMID:24385222

  12. Roughness and function

    NASA Astrophysics Data System (ADS)

    Thomas, T. R.

    2014-01-01

    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.

  13. Functional magnetic microspheres

    NASA Technical Reports Server (NTRS)

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

    1981-01-01

    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.

  14. Nuclear functions of prefoldin

    PubMed Central

    Millán-Zambrano, Gonzalo; Chávez, Sebastián

    2014-01-01

    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

  15. Process for functionalizing alkanes

    DOEpatents

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

    1984-06-12

    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.

  16. [Endothelial function test].

    PubMed

    Tomiyama, Hirofumi

    2015-11-01

    Endothelial dysfunction is thought to have pivotal roles for the development of hypertension, initiation/progression of hypertensive organ damages, and prognosis. In clinical setting, flow-mediated vasodilatation (FMD) of brachial artery is used as a marker of endothelial function. However, well-trained sonographer is needed to conduct FMD measurement, and therefore, FMD has not been fully standardized (i.e., the reference value of FMD has not been established). Even so, FMD predicts future cardiovascular events. Lifestyle modifications (i.e., smoking cessation, exercise, or weight loss) and antihypertensive medication provide beneficial effects on endothelial function. Thus, FMD have a potential as a useful surrogate marker for the management of hypertension. PMID:26619655

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

    SciTech Connect

    Yuan, Rong

    2007-02-06

    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.

  18. Dynamics of cholinergic function

    SciTech Connect

    Hanin, I.

    1986-01-01

    This book presents information on the following topics; cholinergic pathways - anatomy of the central nervous system; aging, DSAT and other clinical conditions; cholinergic pre- and post-synaptic receptors; acetylcholine release; cholinesterases, anticholinesterases and reactivators; acetylcholine synthesis, metabolism and precursors; second messenger messenger mechanisms; interaction of acetylcholine with other neurotransmitter systems; cholinergic mechanisms in physiological function, including cardiovascular events; and neurotoxic agents and false transmitters.

  19. Hermes phasing GNC functions

    NASA Astrophysics Data System (ADS)

    Legenne, J.; Broca, R.; Alby, F.

    1992-08-01

    A review is presented of the French Guidance, Navigation and Control Simulator (GNC) developed to analyze and validate the global phasing strategy of the Hermes spaceplane. The phasing strategy, the events management, and the requirements for simulation are described, and a functional description of the simulator is given. The simulator will be able to assess the performance of the strategy in terms of fuel consumption and duration (mean values, standard deviations).

  20. Executive Functioning in Schizophrenia

    PubMed Central

    Orellana, Gricel; Slachevsky, Andrea

    2013-01-01

    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

  1. Functionalization of Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Webber, Stephen E.

    2003-01-01

    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.

  2. [Functional hypothalamic amenorrhea].

    PubMed

    Stárka, Luboslav; Dušková, Michaela

    2015-10-01

    Functional hypothalamic amenorrhea (FHA) besides pregnancy and syndrome of polycystic ovary is one of the most common causes of secondary amenorrhea. FHA results from the aberrations in pulsatile gonadotropin-releasing hormone (GnRH) secretion, which in turn causes impairment of the gonadotropins (follicle-stimulating hormone and luteinizing hormone). FHA is a form of the defence of organism in situations where life functions are more important than reproductive function. FHA is reversible; it can be normalized after ceasing the stress situation. There are three types of FHA: weight loss related, stress-related, and exercise-related amenorrhea. The final consequences are complex hormonal changes manifested by profound hypoestrogenism. Additionally, these patients present mild hypercortisolemia, low serum insulin levels, low insulin-like growth factor 1 (IGF-1) and low total triiodothyronine. Women health in this disorder is disturbed in several aspects including the skeletal system, cardiovascular system, and mental problems. Patients manifest a decrease in bone mass density, which is related to an increase in fracture risk. Therefore, osteopenia and osteoporosis are the main long-term complications of FHA. Cardiovascular complications include endothelial dysfunction and abnormal changes in the lipid profile. FHA patients present significantly higher depression and anxiety and also sexual problems compared to healthy subjects. PMID:26486482

  3. Functions of multivector variables.

    PubMed

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

    2015-01-01

    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 Cl(R(3)) provides a particularly versatile algebraic framework. PMID:25774689

  4. Mitochondria and Endothelial Function

    PubMed Central

    Kluge, Matthew A.; Fetterman, Jessica L.; Vita, Joseph A.

    2013-01-01

    In contrast to their role in other cell types with higher energy demands, mitochondria in endothelial cells primarily function in signaling cellular responses to environmental cues. This article provides an overview of key aspects of mitochondrial biology in endothelial cells, including subcellular location, biogenesis, dynamics, autophagy, ROS production and signaling, calcium homeostasis, regulated cell death, and heme biosynthesis. In each section, we introduce key concepts and then review studies showing the importance of that mechanism to endothelial control of vasomotor tone, angiogenesis, and inflammatory activation. We particularly highlight the small number of clinical and translational studies that have investigated each mechanism in human subjects. Finally, we review interventions that target different aspects of mitochondrial function and their effects on endothelial function. The ultimate goal of such research is the identification of new approaches for therapy. The reviewed studies make it clear that mitochondria are important in endothelial physiology and pathophysiology. A great deal of work will be needed, however, before mitochondria-directed therapies are available for the prevention and treatment of cardiovascular disease. PMID:23580773

  5. [Function preserving gastrectomy].

    PubMed

    Xu, Danhua; Xu, Jia; Zhu, Chunchao; Li, Maoran; Zhao, Enhao; Yu, Fengrong; Zhao, Gang; Cao, Hui

    2016-02-25

    Under the premise of radical resection in the treatment, it is of great significance to preserve partial gastric function so that the early gastric cancer (EGC) patients' postoperative quality of life (QOL) can be improved. In the patients with EGC in the upper third of the stomach, the emphasis is on the prevention of reflux esophagitis caused by bile and gastric juice reflux. Pylorus-preserving gastrectomy (PPG) is applicable to the patients with EGC in the middle third of the stomach. In the patients with EGC in the lower third of the stomach, distal gastrectomy (DG) is performed in general. Various anastomosis ways are applied to reduce the negative impact of pylorus resection after DG. Furthermore, it should also be considered that reasonable vagal nerves preservation and lymph node dissection are both important for function preserving gastrectomy of EGC. Rational use of laparoscopy-assisted gastrectomy has advantages of lower invasiveness, faster recovery, etc. And the amplification effect of laparoscope can contribute to preserving nerves and gastric function. PMID:26831890

  6. Functional ingredients from microalgae.

    PubMed

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

    2014-08-01

    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

  7. Functional Hemodynamic Monitoring

    PubMed Central

    Pinsky, Michael R.

    2014-01-01

    Functional hemodynamic monitoring is the assessment of the dynamic interactions of hemodynamic variables in response to a defined perturbation. Dynamic tissue O2 saturation (StO2) responses to complete stop flow conditions (vascular occlusion test), which can be created by measuring hand StO2 and occluding flow with a blood pressure cuff, assesses cardiovascular sufficiency and microcirculatory blood flow distribution. 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 non-invasive and across multiple patient groups and clinical conditions. Accordingly, fluid responsiveness can be predicted in a quantities fashion by measuring as arterial pulse pressure variation, left ventricular stroke volume variation or their surrogates during positive pressure breathing or the change in cardiac output response to a passive leg raising maneuver. However, volume responsiveness, though important, reflects only part of the overall spectrum of functional physiological variables that can be measured to define physiologic state and monitor response to therapy. PMID:25435480

  8. Functionalized Amorphous Aluminosilicates

    NASA Astrophysics Data System (ADS)

    Mesgar, Milad

    Alkali treated aluminosilicate (geopolymer) was functionalized by surfactant to increase the hydrophobicity for making Pickering emulsion for the first part of this work. In the first part of this study, alkali treated metakaolin was functionalized with cetyltrimethylammonium bromide ((C16H33)N(CH 3)3Br, CTAB). The electrostatic interaction between this quaternary ammonium and the surface of the aluminosilicate which has negative charge has taken place. The particles then were used to prepare Pickering emulsion. The resulting stable dispersions, obtained very fast at very simple conditions with low ratio of aluminosilicate to liquid phase. In the second part, the interaction between geopolymer and glycerol was studied to see the covalent grafting of the geopolymer for making geopolymer composite. The composite material would be the basis material to be used as support catalyst, thin coating reagent and flame retardant material and so on, Variety of techniques, Thermogravimetric (TGA), Particle-induced X-ray emission (PIXE), FTIR, Solid state NMR, Powder X-ray diffraction (PXRD), BET surface area, Elemental analysis (CHN), TEM, SEM and Optical microscopy were used to characterize the functionalized geopolymer.

  9. Lymphocyte Functions in Microgravity

    NASA Technical Reports Server (NTRS)

    Pellis, Neal R.; Risin, Diane; Sundaresan, A.; Cooper, D.; Dawson, David L. (Technical Monitor)

    1999-01-01

    To understand the mechanism of immunity impairment in space it is important to analyze the direct effects of space-related conditions on different lymphocytes functions. Since 1992, we are investigating the effect of modeled and true microgravity (MG) on numerous lymphocyte functions. We had shown that modeled (MMG) and true microgravity inhibit lymphocyte locomotion through type I collagen. Modeled microgravity also suppresses polyclonal and antigen-specific lymphocyte activation. Polyclonal activation of lymphocytes prior to exposure to MMG abrogates the MG-induced inhibition of lymphocyte locomotion. The relationship between activation deficits and the loss of locomotion in MG was investigated using PKC activation by phorbol ester (PMA) and calcium ionophore (ionomycin). Direct activation of PKC by PMA substantially restored the MMG-inhibited lymphocyte locomotion and PHA-induced lymphocyte activation lonomycin by itself did not restore either locomotion or activation of the lymphocytes, indicating that these changes are not related to the impairment in the calcium flux in MMG. Treatment of lymphocytes with PMA before exposure to MMG prevented the loss of locomotion. It was observed that DNA synthesis is not necessary for restoration of locomotion since mitomicin C treated and untreated cells recovered their locomotion to the same level after PKC activation. Our recent data indicate that microgravity may selectively effect the expression of novel Ca2+ independent isoforms of PKC, in particularly PKC sigma and delta. This provides a new insight in understanding of the mechanisms of MG-sensitive cellular functions.

  10. [Chewing and cognitive function].

    PubMed

    Hirano, Yoshiyuki; Onozuka, Minoru

    2014-01-01

    Chewing does not only crush food to aid swallowing and digestion; it also helps to relieve stress and regulate cognitive functions, including alertness and executive function. It is well known that chewing gum is used for sleepiness prevention during work, learning, and driving. In addition, it has been shown in the elderly that a decrease in the number of residual teeth is related to dementia onset. These findings suggest a link between chewing and maintaining memory and attention. Recently, many studies regarding the effects of chewing on memory and attention were conducted using functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). When a working memory task was used, the middle frontal gyrus in the dorsolateral prefrontal cortex showed greater activation in addition to producing higher alertness after chewing. Furthermore, using an attentional network test, reaction time shortened, and the anterior cingulate cortex and left frontal gyrus were both activated for the executive network. From these results, it is suggested that chewing elevates alertness, consequently leading to improvements in cognitive performance. In this review, we introduce findings concerning the effects of chewing on cognitive performance, and discuss the neuronal mechanisms underlying these effects. PMID:24371128

  11. A Generalized Wall Function

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  12. Functions of Multivector Variables

    PubMed Central

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

    2015-01-01

    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 Cℓ(ℜ3) provides a particularly versatile algebraic framework. PMID:25774689

  13. Carbasugars: Synthesis and Functions

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yoshiyuki

    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.

  14. Lutein and Brain Function

    PubMed Central

    Erdman, John W.; Smith, Joshua W.; Kuchan, Matthew J.; Mohn, Emily S.; Johnson, Elizabeth J.; Rubakhin, Stanislav S.; Wang, Lin; Sweedler, Jonathan V.; Neuringer, Martha

    2015-01-01

    Lutein is one of the most prevalent carotenoids in nature and in the human diet. Together with zeaxanthin, it is highly concentrated as macular pigment in the foveal retina of primates, attenuating blue light exposure, providing protection from photo-oxidation and enhancing visual performance. Recently, interest in lutein has expanded beyond the retina to its possible contributions to brain development and function. Only primates accumulate lutein within the brain, but little is known about its distribution or physiological role. Our team has begun to utilize the rhesus macaque (Macaca mulatta) model to study the uptake and bio-localization of lutein in the brain. Our overall goal has been to assess the association of lutein localization with brain function. In this review, we will first cover the evolution of the non-human primate model for lutein and brain studies, discuss prior association studies of lutein with retina and brain function, and review approaches that can be used to localize brain lutein. We also describe our approach to the biosynthesis of 13C-lutein, which will allow investigation of lutein flux, localization, metabolism and pharmacokinetics. Lastly, we describe potential future research opportunities. PMID:26566524

  15. Vitamin D & endothelial function.

    PubMed

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

    2014-10-01

    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

  16. Development of Functional Foods

    PubMed Central

    MITSUOKA, Tomotari

    2014-01-01

    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

  17. Structure and composition of the Trinil femora: functional and taxonomic implications.

    PubMed

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

    2015-03-01

    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

  18. Generating functionals for Green's functions in gauge field theories

    SciTech Connect

    Bordag, M.; Kaschlun, L.; Matveev, V.A.; Robaschik, D.

    1987-09-01

    The structure of the generating functional of the one-particle-irreducible Green's functions in gauge field theories is investigated. Both axial as well as covariant gauge conditions are considered. For both cases, the general structure of the functionals is obtained, and a functional expansion with respect to nonlocal operators is given. The appearance of gauge-dependent operators in the case of the covariant gauge follows in a natural manner from the structure of the corresponding functional.

  19. Functional genomics of cancer.

    PubMed

    Liu, Edison T

    2008-06-01

    Cancer genomics has focused on the discovery of genetic mutations and chromosomal structural rearrangements that either increase susceptibility to cancer or support the cancer phenotype. Though each individual mutation may induce specific cancer phenotypes, it is the interaction of the functional changes in transcription and proteins that give the characteristics of cancer. Whereas molecular biology focuses on the impact of individual genes on the cancer state, functional genomics assesses the comprehensive genetic alterations in a cancer cell and seeks to integrate the dynamic changes in these networks so that cancer phenotypes can be explained. Most commonly, the transcriptome is the target of analysis because of the maturity, completeness, and speed of the technologies, but progressively the proteome is being studied in the same comprehensive manner. The focus of this review, however, will be on the functional consequences of cancer genomic alterations with special reference to the transcriptome and in the perturbed gene expression found in cancer states. The developments in the past two years (which is our time horizon) have been heavily driven by the applications of the new ultra high-throughput sequencing approaches assisted by computational discovery strategies. The precision and comprehensiveness of the analyses are astonishing. The collective results, when taken together, suggest that despite the large range of mutational and epigenetic events, there is a convergence onto a finite number of pathways that drive cancer behavior. Moreover, the interconnectivity of regulatory control mechanisms suggest that the earlier concepts distinguishing driver from passenger abnormalities may undervalue the contribution of the numerous aberrations that have small but additive effects on cancer virulence. PMID:18691651

  20. Functional fractionation of platelets.

    PubMed

    Haver, V M; Gear, A R

    1981-02-01

    Studies of platelet populations suggest that they are heterogeneous in size, age, and metabolic parameters. In an attempt to correlate these parameters with efficiency of aggregation, a new technique, functional fractionation, was developed. Platelet populations are separated by their differential reactivity to aggregating agents. For example, low doses of ADP (0.1 to 0.7 microM) are added to stirred PRP, after which gentle centrifugation is used to remove aggregates from single unreacted platelets. The loose aggregates can be readily dispersed for comparison of the physical or biochemical properties of the reacted versus unreacted platelets. It was found that reactive platelets were larger (6.5 micrometer3) than unreacted platelets (5.51 micrometer3). No significant difference in density existed between the two populations, and no release of [14C]serotonin from prelabeled platelets occurred during functional fractionation. Scanning and transmission electron microscopy confirmed the size difference and revealed that in both populations platelets were structurally intact with a normal discoid shape and no significant difference in organelle content. Human platelets most reactive to ADP were also enriched in glycogen (3.6-fold), ATP (1.6-fold), and ADP (twofold), compared with less reactive cells. These "reactive" cells took up more 51[Cr] and contained 1.9 times more surface sialic acid. In an in vivo aging experiment, rats were injected with 75[Se]methionine. Shortly after labeling (1 day), the most reactive platelets possessed the highest amount of 75[Se]. These results reveal that functionally active platelets, which are also larger, are more active metabolically than less reactive platelets, possess a higher negative surface charge, and may be a younger population. PMID:7452090

  1. NEUROFEEDBACK USING FUNCTIONAL SPECTROSCOPY

    PubMed Central

    Hinds, Oliver; Wighton, Paul; Tisdall, M. Dylan; Hess, Aaron; Breiter, Hans; van der Kouwe, André

    2014-01-01

    Neurofeedback based on real-time measurement of the blood oxygenation level-dependent (BOLD) signal has potential for treatment of neurological disorders and behavioral enhancement. Commonly employed methods are based on functional magnetic resonance imaging (fMRI) sequences that sacrifice speed and accuracy for whole-brain coverage, which is unnecessary in most applications. We present multi-voxel functional spectroscopy (MVFS): a system for computing the BOLD signal from multiple volumes of interest (VOI) in real-time that improves speed and accuracy of neurofeedback. MVFS consists of a functional spectroscopy (FS) pulse sequence, a BOLD reconstruction component, a neural activation estimator, and a stimulus system. The FS pulse sequence is a single-voxel, magnetic resonance spectroscopy sequence without water suppression that has been extended to allow acquisition of a different VOI at each repetition and real-time subject head motion compensation. The BOLD reconstruction component determines the T2* decay rate, which is directly related to BOLD signal strength. The neural activation estimator discounts nuisance signals and scales the activation relative to the amount of ROI noise. Finally, the neurofeedback system presents neural activation-dependent stimuli to experimental subjects with an overall delay of less than 1s. Here we present the MVFS system, validation of certain components, examples of its usage in a practical application, and a direct comparison of FS and echo-planar imaging BOLD measurements. We conclude that in the context of realtime BOLD imaging, MVFS can provide superior accuracy and temporal resolution compared with standard fMRI methods. PMID:24999293

  2. NEUROFEEDBACK USING FUNCTIONAL SPECTROSCOPY.

    PubMed

    Hinds, Oliver; Wighton, Paul; Tisdall, M Dylan; Hess, Aaron; Breiter, Hans; van der Kouwe, André

    2014-06-01

    Neurofeedback based on real-time measurement of the blood oxygenation level-dependent (BOLD) signal has potential for treatment of neurological disorders and behavioral enhancement. Commonly employed methods are based on functional magnetic resonance imaging (fMRI) sequences that sacrifice speed and accuracy for whole-brain coverage, which is unnecessary in most applications. We present multi-voxel functional spectroscopy (MVFS): a system for computing the BOLD signal from multiple volumes of interest (VOI) in real-time that improves speed and accuracy of neurofeedback. MVFS consists of a functional spectroscopy (FS) pulse sequence, a BOLD reconstruction component, a neural activation estimator, and a stimulus system. The FS pulse sequence is a single-voxel, magnetic resonance spectroscopy sequence without water suppression that has been extended to allow acquisition of a different VOI at each repetition and real-time subject head motion compensation. The BOLD reconstruction component determines the T2* decay rate, which is directly related to BOLD signal strength. The neural activation estimator discounts nuisance signals and scales the activation relative to the amount of ROI noise. Finally, the neurofeedback system presents neural activation-dependent stimuli to experimental subjects with an overall delay of less than 1s. Here we present the MVFS system, validation of certain components, examples of its usage in a practical application, and a direct comparison of FS and echo-planar imaging BOLD measurements. We conclude that in the context of realtime BOLD imaging, MVFS can provide superior accuracy and temporal resolution compared with standard fMRI methods. PMID:24999293

  3. Functional DNA Nanomaterials

    NASA Astrophysics Data System (ADS)

    Zhao, Zhao

    The discovery of DNA helical structure opened the door of modern molecular biology. Ned Seeman utilized DNA as building block to construct different nanoscale materials, and introduced a new field, know as DNA nanotechnology. After several decades of development, different DNA structures had been created, with different dimension, different morphology and even with complex curvatures. In addition, after construction of enough amounts DNA structure candidates, DNA structure template, with excellent spatial addressability, had been used to direct the assembly of different nanomaterials, including nanoparticles and proteins, to produce different functional nanomaterials. However there are still many challenges to fabricate functional DNA nanostructures. The first difficulty is that the present finite sized template dimension is still very small, usually smaller than 100nm, which will limit the application for large amount of nanomaterials assembly or large sized nanomaterials assembly. Here we tried to solve this problem through developing a new method, superorigami, to construct finite sized DNA structure with much larger dimension, which can be as large as 500nm. The second problem will be explored the ability of DNA structure to assemble inorganic nanomaterials for novel photonic or electronic properties. Here we tried to utilize DNA Origami method to assemble AuNPs with controlled 3D spacial position for possible chiral photonic complex. We also tried to assemble SWNT with discrete length for possible field effect transistor device. In addition, we tried to mimic in vivo compartment with DNA structure to study internalized enzyme behavior. From our results, constructed DNA cage origami can protect encapsulated enzyme from degradation, and internalized enzyme activity can be boosted for up to 10 folds. In summary, DNA structure can serve as an ideal template for construction of functional nanomaterials with lots of possibilities to be explored.

  4. Defining functional dyspepsia.

    PubMed

    Mearin, Fermín; Calleja, José Luis

    2011-12-01

    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

  5. Dendritic function in vivo.

    PubMed

    Grienberger, Christine; Chen, Xiaowei; Konnerth, Arthur

    2015-01-01

    Dendrites are the predominant entry site for excitatory synaptic potentials in most types of central neurons. There is increasing evidence that dendrites are not just passive transmitting devices but play active roles in synaptic integration through linear and non-linear mechanisms. Frequently, excitatory synapses are formed on dendritic spines. In addition to relaying incoming electrical signals, spines can play important roles in modifying these signals through complex biochemical processes and, thereby, determine learning and memory formation. Here, we review recent advances in our understanding of the function of spines and dendrites in central mammalian neurons in vivo by focusing particularly on insights obtained from Ca(2+) imaging studies. PMID:25432423

  6. Dual-functional semithiobambusurils.

    PubMed

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

    2015-01-01

    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

  7. The Broadening Functions Technique

    NASA Astrophysics Data System (ADS)

    Rucinski, Slavek M.

    2012-04-01

    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.

  8. Stress and adrenal function.

    PubMed

    Harvey, S; Phillips, J G; Rees, A; Hall, T R

    1984-12-01

    The natural environment is composed of various potentially hostile stressors. It is a basic requirement of life that the cells of an organism must be maintained within closely defined physiological limits. The maintenance of a constant interior mileu results from physiological and behavioural homeostatic adaptations. The physiological regulation of homeostatis is achieved by complex endocrine interactions, principally by the hormones secreted from the adrenal glands. In this brief review the responses of the avian adrenal glands to stressful stimuli, the mechanism of adrenal activation, and the function of the adrenal responses will be considered. PMID:6097634

  9. Functional abdominal bloating.

    PubMed

    Sullivan, S N

    1994-07-01

    Ten to 25% of healthy persons have bloating at some time or other. It is very common in those with the irritable bowel syndrome, constipation, or anorexia nervosa. Although the cause of functional bloating remains unknown, old explanations such as a low diaphragm, exaggerated lumbar lordosis, and psychiatric problems have been disproved. New suggestions on its etiology include recent weight gain, weak abdominal muscles, and retained fluid in loops of small intestine. No treatment is of proven benefit, but treatment by weight loss, exercise, and prokinetics should be studied. PMID:7930428

  10. Bayes multiple decision functions

    PubMed Central

    Wu, Wensong; Peña, Edsel A.

    2014-01-01

    This paper deals with the problem of simultaneously making many (M) binary decisions based on one realization of a random data matrix X. M is typically large and X will usually have M rows associated with each of the M decisions to make, but for each row the data may be low dimensional. Such problems arise in many practical areas such as the biological and medical sciences, where the available dataset is from microarrays or other high-throughput technology and with the goal being to decide which among of many genes are relevant with respect to some phenotype of interest; in the engineering and reliability sciences; in astronomy; in education; and in business. A Bayesian decision-theoretic approach to this problem is implemented with the overall loss function being a cost-weighted linear combination of Type I and Type II loss functions. The class of loss functions considered allows for use of the false discovery rate (FDR), false nondiscovery rate (FNR), and missed discovery rate (MDR) in assessing the quality of decision. Through this Bayesian paradigm, the Bayes multiple decision function (BMDF) is derived and an efficient algorithm to obtain the optimal Bayes action is described. In contrast to many works in the literature where the rows of the matrix X are assumed to be stochastically independent, we allow a dependent data structure with the associations obtained through a class of frailty-induced Archimedean copulas. In particular, non-Gaussian dependent data structure, which is typical with failure-time data, can be entertained. The numerical implementation of the determination of the Bayes optimal action is facilitated through sequential Monte Carlo techniques. The theory developed could also be extended to the problem of multiple hypotheses testing, multiple classification and prediction, and high-dimensional variable selection. The proposed procedure is illustrated for the simple versus simple hypotheses setting and for the composite hypotheses setting through simulation studies. The procedure is also applied to a subset of a microarray data set from a colon cancer study. PMID:25414762

  11. Functional Foods for Women's Health.

    ERIC Educational Resources Information Center

    Lindeman, Alice K.

    2002-01-01

    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…

  12. A Primer on Functional Analysis

    ERIC Educational Resources Information Center

    Yoman, Jerome

    2008-01-01

    This article presents principles and basic steps for practitioners to complete a functional analysis of client behavior. The emphasis is on application of functional analysis to adult mental health clients. The article includes a detailed flow chart containing all major functional diagnoses and behavioral interventions, with functional assessment…

  13. A Primer on Functional Analysis

    ERIC Educational Resources Information Center

    Yoman, Jerome

    2008-01-01

    This article presents principles and basic steps for practitioners to complete a functional analysis of client behavior. The emphasis is on application of functional analysis to adult mental health clients. The article includes a detailed flow chart containing all major functional diagnoses and behavioral interventions, with functional assessment

  14. Functional Foods for Women's Health.

    ERIC Educational Resources Information Center

    Lindeman, Alice K.

    2002-01-01

    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

  15. Pfaffian and Determinantal Tau Functions

    NASA Astrophysics Data System (ADS)

    van de Leur, Johan W.; Orlov, Alexander Yu.

    2015-11-01

    Adler, Shiota and van Moerbeke observed that a tau function of the Pfaff lattice is a square root of a tau function of the Toda lattice hierarchy of Ueno and Takasaki. In this paper, we give a representation theoretical explanation for this phenomenon. We consider 2-BKP and two-component 2-KP tau functions. We shall show that a square of a BKP tau function is equal to a certain two-component KP tau function and a square of a 2-BKP tau function is equal to a certain two-component 2-KP tau function.

  16. MITOCHONDRIAL FUNCTION IN SEPSIS.

    PubMed

    Arulkumaran, Nishkantha; Deutschman, Clifford S; Pinsky, Michael R; Zuckerbraun, Brian; Schumacker, Paul T; Gomez, Hernando; Gomez, Alonso; Murray, Patrick; Kellum, John A

    2016-03-01

    Mitochondria are an essential part of the cellular infrastructure, being the primary site for high-energy adenosine triphosphate production through oxidative phosphorylation. Clearly, in severe systemic inflammatory states, like sepsis, cellular metabolism is usually altered, and end organ dysfunction is not only common, but also predictive of long-term morbidity and mortality. Clearly, interest is mitochondrial function both as a target for intracellular injury and response to extrinsic stress have been a major focus of basic science and clinical research into the pathophysiology of acute illness. However, mitochondria have multiple metabolic and signaling functions that may be central in both the expression of sepsis and its ultimate outcome. In this review, the authors address five primary questions centered on the role of mitochondria in sepsis. This review should be used both as a summary source in placing mitochondrial physiology within the context of acute illness and as a focal point for addressing new research into diagnostic and treatment opportunities these insights provide. PMID:26871665

  17. Adaptive Hotelling discriminant functions

    NASA Astrophysics Data System (ADS)

    Brème, Arthur; Kupinski, Matthew A.; Clarkson, Eric; Barrett, Harrison H.

    2007-03-01

    Any observer performing a detection task on an image produces a single number that represents the observer's confidence that a signal (e.g., a tumor) is present. A linear observer produces this test statistic using a linear template or a linear discriminant. The optimal linear discriminant is well-known to be the Hotelling observer and uses both first- and second-order statistics of the image data. There are many situations where it is advantageous to consider discriminant functions that adapt themselves to some characteristics of the data. In these situations, the linear template is itself a function of the data and, thus, the observer is nonlinear. In this paper, we present an example adaptive Hotelling discriminant and compare the performance of this observer to that of the Hotelling observer and the Bayesian ideal observer. The task is to detect a signal that is imbedded in one of a finite number of possible random backgrounds. Each random background is Gaussian but has different covariance properties. The observer uses the image data to determine which background type is present and then uses the template appropriate for that background. We show that the performance of this particular observer falls between that of Hotelling and ideal observers.

  18. Mast Cell Function

    PubMed Central

    da Silva, Elaine Zayas Marcelino; Jamur, Maria Célia

    2014-01-01

    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

  19. Functional anorectal disorders.

    PubMed

    Whitehead, W E

    1996-10-01

    The functional anorectal disorders-functional fecal incontinence, pelvic floor dyssynergia-type constipation, levator ani syndrome, and proctalgia fugax-are common but poorly understood gastrointestinal complaints. Fecal incontinence may occur in constipated patients when a fecal impaction of the rectum reflexly inhibits the internal anal sphincter and allows leakage of soft stool, or it may occur in diarrhea. Constipation-related incontinence can be treated with habit training (use of a routine time to defecate backed up by laxatives) or biofeedback to teach relaxation of the pelvic floor, but diarrhea-related fecal incontinence usually requires antidiarrheal medications. Pelvic floor dyssynergia occurs when the pelvic floor muscles paradoxically contract instead of relaxing when the patient strains to defecate. Biofeedback to teach relaxation of these muscles is effective in two thirds of patients. Levator ani syndrome involves chronic, and proctalgia fugax involves fleeting rectal pain. The cause of these painful conditions is unknown, and no treatment of proven efficacy is available. PMID:8902936

  20. Verbal Functions in Psychopathy.

    PubMed

    de Almeida Brites, José; Ladera, Valentina; Perea, Victoria; García, Ricardo

    2015-12-01

    The aim of this study was to compare the verbal functions and language skills of male psychopathic individuals (in prison and outside) with non-psychopaths. The purpose was therefore to analyze phonological processing, reading and writing skills, the meaning of words and images, and the understanding of sentences. Ninety individuals with an average age of 38.19 (SD = 7.67) voluntarily participated in this study. The data were collected in different settings: prisons, a private charitable organization, and private clinics and health centers. All participants completed the Psychopathy Checklist Revised and the Psycholinguistic Assessment of Language Processing in Aphasia, to assess psychopathy traits and language skills, respectively. Participants were allocated into four different groups: incarcerated psychopathic offenders (n = 13), non-incarcerated psychopathic non-offenders living in the community (n = 13), incarcerated non-psychopathic offenders (n = 25), and non-psychopathic non-offenders living in the community (n = 39). The results showed that the verbal functions and language skills between psychopaths and non-psychopaths are very similar, showing a common profile. The data presented indicate the need for more specific work opportunities for both groups within the correctional setting, with the use of appropriate language and individualized programs as necessary. PMID:25090993

  1. Optogenetic Functional MRI.

    PubMed

    Lin, Peter; Fang, Zhongnan; Liu, Jia; Lee, Jin Hyung

    2016-01-01

    The investigation of the functional connectivity of precise neural circuits across the entire intact brain can be achieved through optogenetic functional magnetic resonance imaging (ofMRI), which is a novel technique that combines the relatively high spatial resolution of high-field fMRI with the precision of optogenetic stimulation. Fiber optics that enable delivery of specific wavelengths of light deep into the brain in vivo are implanted into regions of interest in order to specifically stimulate targeted cell types that have been genetically induced to express light-sensitive trans-membrane conductance channels, called opsins. fMRI is used to provide a non-invasive method of determining the brain's global dynamic response to optogenetic stimulation of specific neural circuits through measurement of the blood-oxygen-level-dependent (BOLD) signal, which provides an indirect measurement of neuronal activity. This protocol describes the construction of fiber optic implants, the implantation surgeries, the imaging with photostimulation and the data analysis required to successfully perform ofMRI. In summary, the precise stimulation and whole-brain monitoring ability of ofMRI are crucial factors in making ofMRI a powerful tool for the study of the connectomics of the brain in both healthy and diseased states. PMID:27167840

  2. Varicocele and testicular function

    PubMed Central

    Pastuszak, Alexander W; Wang, Run

    2015-01-01

    Testicular varicocele, a dilation of the veins of the pampiniform plexus thought to increase testicular temperature via venous congestion, is commonly associated with male infertility. Significant study has clarified the negative impact of varicocele on semen parameters and more recent work has shed light on its detrimental effects on the molecular and ultrastructural features of sperm and the testicular microenvironment, as well as more clearly defined the positive impacts of treatment on couples’ fertility. The relationship between varicocele and testicular endocrine function, while known for some time based on histologic evaluation, has become more apparent in the clinical setting with a growing link between varicocele and hypogonadism. Finally, in the pediatric setting, while future study will clarify the impact of varicocele on fertility and testicular function, recent work supports a parallel effect of varicocele in adolescents and adults, suggesting a re-evaluation of current treatment approaches in light of the progressive nature of the condition and potential increased risk of future disease. PMID:25926610

  3. Poverty impedes cognitive function.

    PubMed

    Mani, Anandi; Mullainathan, Sendhil; Shafir, Eldar; Zhao, Jiaying

    2013-08-30

    The poor often behave in less capable ways, which can further perpetuate poverty. We hypothesize that poverty directly impedes cognitive function and present two studies that test this hypothesis. First, we experimentally induced thoughts about finances and found that this reduces cognitive performance among poor but not in well-off participants. Second, we examined the cognitive function of farmers over the planting cycle. We found that the same farmer shows diminished cognitive performance before harvest, when poor, as compared with after harvest, when rich. This cannot be explained by differences in time available, nutrition, or work effort. Nor can it be explained with stress: Although farmers do show more stress before harvest, that does not account for diminished cognitive performance. Instead, it appears that poverty itself reduces cognitive capacity. We suggest that this is because poverty-related concerns consume mental resources, leaving less for other tasks. These data provide a previously unexamined perspective and help explain a spectrum of behaviors among the poor. We discuss some implications for poverty policy. PMID:23990553

  4. Process for functionalizing alkanes

    DOEpatents

    Bergman, Robert G.; Janowicz, Andrew H.; Periana-Pillai, Roy A.

    1985-01-01

    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.

  5. Process for functionalizing alkanes

    DOEpatents

    Bergman, Robert G.; Janowicz, Andrew H.; Periana, Roy A.

    1988-01-01

    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.

  6. Fukui function and response function for nonlocal and fractional systems

    NASA Astrophysics Data System (ADS)

    Peng, Degao; Yang, Weitao

    2013-05-01

    We present extensions to our previous work on Fukui functions and linear-response functions [W. Yang, A. J. Cohen, F. D. Proft, and P. Geerlings, J. Chem. Phys. 136, 144110 (2012), 10.1063/1.3701562]. Viewed as energy derivatives with respect to the number of electrons and the external potential, all second-order derivatives (the linear-response function, the Fukui function, and the chemical hardness) are extended to fractional systems, and all third-order derivatives (the second-order response function, the Fukui response function, the dual descriptor, and the hyperhardness) for integer systems are also obtained. These analytical derivatives are verified by finite difference numerical derivatives. In the context of the exact linearity condition and the constancy condition, these analytical derivatives enrich greatly the information of the exact conditions on the energy functional through establishing real-space dependency. The introduction of an external nonlocal potential defines the nonlocal Fukui function and the nonlocal linear-response function. The nonlocal linear-response function so defined also provides the precise meaning for the time-dependent linear-response density-functional theory calculations with generalized Kohn-Sham functionals. These extensions will be useful to conceptual density-functional theory and density functional development.

  7. Commentary: freedom and function.

    PubMed

    Buchanan, Alec

    2008-01-01

    While the question of whether our actions are determined or are the result of free will is a deep one in philosophy, it does not need to be answered for forensic psychiatrists to give evidence in court. As Stephen Morse has pointed out, the absence of free will is not named as an excusing condition. The insanity defense, for instance, requires proof of functional impairment, to which psychiatrists can usefully testify. Of the approaches available to determinism, my own preference is that of Herbert Hart: until we know that determinism is true, we will continue to prefer a system that requires persons to have made proper choices to act as they did before we hold them responsible. This seems to resemble Dr. Felthous' preferred option, that mentally responsible choices are choices made in the presence of a relatively natural ability to have decided otherwise. PMID:18354119

  8. Functionalization of ?-synuclein fibrils

    PubMed Central

    ?asait?, Vida; Bukauskas, Virginijus; etkus, Ar?nas; Staniulis, Juozas; Mekys, Rolandas

    2015-01-01

    Summary 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

  9. Density functional theory.

    PubMed

    Orio, Maylis; Pantazis, Dimitrios A; Neese, Frank

    2009-01-01

    Density functional theory (DFT) finds increasing use in applications related to biological systems. Advancements in methodology and implementations have reached a point where predicted properties of reasonable to high quality can be obtained. Thus, DFT studies can complement experimental investigations, or even venture with some confidence into experimentally unexplored territory. In the present contribution, we provide an overview of the properties that can be calculated with DFT, such as geometries, energies, reaction mechanisms, and spectroscopic properties. A wide range of spectroscopic parameters is nowadays accessible with DFT, including quantities related to infrared and optical spectra, X-ray absorption and Mössbauer, as well as all of the magnetic properties connected with electron paramagnetic resonance spectroscopy except relaxation times. We highlight each of these fields of application with selected examples from the recent literature and comment on the capabilities and limitations of current methods. PMID:19238578

  10. Exercise and functional foods

    PubMed Central

    Aoi, Wataru; Naito, Yuji; Yoshikawa, Toshikazu

    2006-01-01

    Appropriate nutrition is an essential prerequisite for effective improvement of athletic performance, conditioning, recovery from fatigue after exercise, and avoidance of injury. Nutritional supplements containing carbohydrates, proteins, vitamins, and minerals have been widely used in various sporting fields to provide a boost to the recommended daily allowance. In addition, several natural food components have been found to show physiological effects, and some of them are considered to be useful for promoting exercise performance or for prevention of injury. However, these foods should only be used when there is clear scientific evidence and with understanding of the physiological changes caused by exercise. This article describes various "functional foods" that have been reported to be effective for improving exercise performance or health promotion, along with the relevant physiological changes that occur during exercise. PMID:16749944

  11. Brain Dynamics Promotes Function

    NASA Astrophysics Data System (ADS)

    Lourenço, Carlos

    Dynamical structure in the brain promotes biological function. Natural scientists look for correlations between measured electrical signals and behavior or mental states. Computational scientists have new opportunities to receive ’algorithmic’ inspiration from brain processes and propose computational paradigms. Thus a tradition which dates back to the 1940s with neural nets research is renewed. Real processes in the brain are ’complex’ and withstand trivial descriptions. However, dynamical complexity need not be at odds with a computational description of the phenomena and with the inspiration for algorithms that actually compute something in an engineering sense. We engage this complexity from a computational viewpoint, not excluding dynamical regimes that a number of authors are willing to label as chaos. The key question is: what may we be missing computation-wise if we overlook brain dynamics? At this point in brain research, we are happy if we can at least provide a partial answer.

  12. Evolution of catalytic function

    NASA Technical Reports Server (NTRS)

    Joyce, G. F.

    1993-01-01

    An RNA-based evolution system was constructed in the laboratory and used to develop RNA enzymes with novel catalytic function. By controlling the nature of the catalytic task that the molecules must perform in order to survive, it is possible to direct the evolving population toward the expression of some desired catalytic behavior. More recently, this system has been coupled to an in vitro translation procedure, raising the possibility of evolving protein enzymes in the laboratory to produce novel proteins with desired catalytic properties. The aim of this line of research is to reduce darwinian evolution, the fundamental process of biology, to a laboratory procedure that can be made to operate in the service of organic synthesis.

  13. Functional Supramolecular Polymers*

    PubMed Central

    Aida, T.; Meijer, E.W.; Stupp, S.I.

    2012-01-01

    Supramolecular polymers can be random and entangled coils with the mechanical properties of plastics and elastomers, but with great capacity for processability, recycling, and self-healing due to their reversible monomer-to-polymer transitions. At the other extreme, supramolecular polymers can be formed by self-assembly among designed subunits to yield shape-persistent and highly ordered filaments. The use of strong and directional interactions among molecular subunits can achieve not only rich dynamic behavior but also high degrees of internal order that are not known in ordinary polymers. They can resemble, for example, the ordered and dynamic one-dimensional supramolecular assemblies of the cell cytoskeleton, and possess useful biological and electronic functions. PMID:22344437

  14. [Functional neurosurgery for spasticity].

    PubMed

    Ayuzawa, Satoshi; Ihara, Satoshi; Aoki, Tsukasa

    2014-09-01

    The basic concept of neurosurgical procedures to treat spasticity is to decrease the hyperactivity of the stretch reflex. Selective peripheral neurotomy is a method to partially resect the peripheral motor nerve. The alpha motor and Ia afferent nerves are resected, but the latter is essential owing to its lasting effect in reducing spasticity. Focal spasticity in adult patients can be effectively treated using peripheral neurotomy. Functional posterior rhizotomy, mostly used to treat paraplegic spasticity in children with cerebral palsy, involves the sectioning of posterior rootlets associated with abnormal motor responses to electrical stimulation. Intrathecal baclofen therapy is useful in treating diffuse spasticity. Baclofen inhibits the activity of alpha motor neurons both pre and post synaptically at the level of the spinal cord. A decrease in Hmax/Mmax in the H-reflex electrophysiologically represents the effectiveness of these procedures. Good clinical results can be achieved by appropriate indication depending on the clinical features of spasticity in each patient. PMID:25200577

  15. The periinsular functional hemispherotomy.

    PubMed

    Rangel-Castilla, Leonardo; Hwang, Steven W; Al-Shamy, George; Jea, Andrew; Curry, Daniel J

    2012-03-01

    The surgical treatment of refractory epilepsy has evolved as new innovations have been created. Disconnective procedures such as hemispherectomy have evolved. Presently, hemispherotomy has replaced hemispherectomy to reduce complication rates while maintaining good seizure control. Several disconnective techniques have been described including the Rasmussen, vertical, and lateral approaches. The lateral approach, or periinsular hemispherectomy, was derived from modifications on the functional hemispherectomy and involves removal of the temporal lobe mesial structures, exposure of the atrium via the circular sulcus, internal capsule transection under the central sulcus, intraventricular callosotomy, and frontobasal disconnection. The purpose of this article is to describe and illustrate in detail the anatomy and operative technique for periinsular hemispherotomy, as well as to discuss the nuances and issues involved with this procedure. PMID:22380861

  16. Multi-functional windows

    NASA Astrophysics Data System (ADS)

    Nag, Nagendra; Goldman, Lee M.; Balasubramanian, Sreeram; Sastri, Suri

    2013-06-01

    The requirements for modern aircraft are driving the need for conformal windows for future sensor systems. However, limitations on optical systems and the physical properties of optically transparent materials currently limit the geometry of existing windows and window assemblies to faceted assemblies of flat windows held in weight bearing frames. Novel material systems will have to be developed which combine different materials (e.g. ductile metals with transparent ceramics) into structures that combine transparency with structural integrity. Surmet's demonstrated ability to produce novel transparent ceramic/metal structures will allow us to produce such structures in the types of conformal shapes required for future aircraft applications. Furthermore, the ability to incorporate transparencies into such structures also holds out the promise of creating multi-functional windows which provide a broad range of capabilities that might include RF antennas and de-icing in addition to transparency. Recent results in this area will be presented.

  17. Functional replacements for gluten.

    PubMed

    Zannini, Emanuele; Jones, Julie Miller; Renzetti, Stefano; Arendt, Elke K

    2012-01-01

    Celiac disease (CD) is an immune-mediated disease triggered in genetically susceptible individuals by ingested gluten from wheat, rye, barley, and other closely related cereal grains. Currently, the only therapy able to normalize the clinical and histological manifestation of the disease is a strict and life-long gluten-free (GF) diet. The replacement of gluten presents a significant technological challenge, as it is an essential structure-building protein, which is necessary for formulating high-quality baked goods. The objective of this paper is to review some basics about CD, its current prevalence, and the recent advances in the preparation of high-quality GF breads using GF flours, starches, hydrocolloids, gums, and novel functional ingredients and technologies. PMID:22385166

  18. Spices as functional foods.

    PubMed

    Viuda-Martos, M; Ruiz-Navajas, Y; Fernández-López, J; Pérez-Alvarez, J A

    2011-01-01

    Spices and aromatic herbs have been used since antiquity as preservatives, colorants, and flavor enhancers. Spices, which have long been the basis of traditional medicine in many countries, have also been the subject of study, particularly by the chemical, pharmaceutical, and food industries, because of their potential use for improving health. Both in vitro and in vivo studies have demonstrated how these substances act as antioxidants, digestive stimulants, and hypolipidemics and show antibacterial, anti-inflammatory, antiviral, and anticancerigenic activities. These beneficial physiological effects may also have possible preventative applications in a variety of pathologies. The aim of this review is to present an overview of the potential of spices and aromatic herbs as functional foods. PMID:21229415

  19. Corrosion Damage Functions

    SciTech Connect

    Jones, Russell H.

    2002-11-30

    Corrosion damage can lead to reduced operational lifetimes. Often this damage is not as obvious as general corrosion but takes the form of pits, intergranular corrosion, crevice corrosion and hydrogen absorption. These types of corrosion damage lead to stress corrosion cracking, hydrogen induced cracking and corrosion fatigue. A critical step in defining a corrosion damage function is determining the relationship between the corrosion damage, the resulting crack propagation mechanism and component lifetimes. The sequence of events is often some localized corrosion event such as pitting, transition of the pit to a planar crack, propagation of this short crack, transition of the short crack to long crack conditions and continued propagation through Stage I, II, and III of the long crack SCC regimes. A description of critical corrosion damage processes and examples of the transition to long crack SCC conditions will be discussed.

  20. MAGNETARS VERSUS HIGH MAGNETIC FIELD PULSARS: A THEORETICAL INTERPRETATION OF THE APPARENT DICHOTOMY

    SciTech Connect

    Pons, Jose A.; Perna, Rosalba

    2011-11-10

    Highly magnetized neutron stars (NSs) are characterized by a bewildering range of astrophysical manifestations. Here, building on our simulations of the evolution of magnetic stresses in the NS crust and its ensuing fractures, we explore in detail, for the middle-aged and old NSs, the dependence of starquake frequency and energetics on the relative strength of the poloidal (B{sub p}) and toroidal (B{sub tor}) components. We find that, for B{sub p} {approx}> 10{sup 14} G, since a strong crustal toroidal field B{sub tor} {approx} B{sub p} is quickly formed on a Hall timescale, the initial toroidal field needs to be B{sub tor} >> B{sub p} to have a clear influence on the outbursting behavior. For initial fields B{sub p} {approx}< 10{sup 14} G, it is very unlikely that a middle-aged (t {approx} 10{sup 5} years) NS shows any bursting activity. This study allows us to solve the apparent puzzle of how NSs with similar dipolar magnetic fields can behave in a remarkably different way: an outbursting 'magnetar' with a high X-ray luminosity, or a quiet, low-luminosity, 'high-B' radio pulsar. As an example, we consider the specific cases of the magnetar 1E 2259+586 and the radio pulsar PSR J1814-1744, which at present have a similar dipolar field {approx}6 Multiplication-Sign 10{sup 13} G. We determine for each object an initial magnetic field configuration that reproduces the observed timing parameters at their current age. The same two configurations also account for the differences in quiescent X-ray luminosity and for the 'magnetar/outbursting' behavior of 1E 2259+586 but not of PSR J1814-1744. We further use the theoretically predicted surface temperature distribution to compute the light curve for these objects. In the case of 1E 2259+586, for which data are available, our predicted temperature distribution gives rise to a pulse profile whose double-peaked nature and modulation level are consistent with the observations.