Afferent control of central pattern generators: experimental analysis of locomotion in the decerebrate cat.

Science.gov (United States)

Baev, K V; Esipenko, V B; Shimansky YuP

1991-01-01

Changes in the motor activity of the spinal locomotor generator evoked by tonic and phasic peripheral afferent signals during fictitious locomotion of both slow and fast rhythms were analysed in the cat. The tonic afferent inflow was conditioned by the position of the hindlimb. The phasic afferent signals were imitated by electrical stimulation of hindlimb nerves. The correlation between the kinematics of hindlimb locomotor movement and sensory inflow was investigated during actual locomotion. Reliable correlations between motor activity parameters during fictitious locomotion were revealed in cases of both slow and fast "locomotor" rhythms. The main difference between these cases was that correlations "duration-intensity" were positive in the first and negative in the second case. The functional role of "locomotor" pattern dependence on tonic sensory inflow consisted of providing stability for planting the hindlimb on the ground. For any investigated afferent input the phase moments in the "locomotor" cycle were found, in which an afferent signal caused no rearrangement in locomotor generator activity. These moments corresponded to the transitions between "flexion" and "extension" phases and to the bursts of integral afferent activity observed during real locomotion. The data obtained are compared with the results previously described for the scratching generator. The character of changes in "locomotor" activity in response to tonic and phasic sensory signals was similar to that of such changes in "scratching" rhythm in the case of fast "locomotion". Intensification of the "flexion" phase caused by phasic high-intensity stimulation of cutaneous afferents during low "locomotor" rhythm was changed to inhibition (such as observed during "scratching") when this rhythm was fast. It is concluded that the main regularities of peripheral afferent control for both the locomotor and scratching generators are the same. Moreover, these central pattern generators are just

A 3D stand generator for central Appalachian hardwood forests

Science.gov (United States)

Jingxin Wang; Yaoxiang Li; Gary W. Miller

2002-01-01

A 3-dimensional (3D) stand generator was developed for central Appalachian hardwood forests. It was designed for a harvesting simulator to examine the interactions of stand, harvest, and machine. The Component Object Model (COM) was used to design and implement the program. Input to the generator includes species composition, stand density, and spatial pattern. Output...

The contribution of a central pattern generator in a reflex-based neuromuscular model

Science.gov (United States)

Dzeladini, Florin; van den Kieboom, Jesse; Ijspeert, Auke

2014-01-01

Although the concept of central pattern generators (CPGs) controlling locomotion in vertebrates is widely accepted, the presence of specialized CPGs in human locomotion is still a matter of debate. An interesting numerical model developed in the 90s’ demonstrated the important role CPGs could play in human locomotion, both in terms of stability against perturbations, and in terms of speed control. Recently, a reflex-based neuro-musculo-skeletal model has been proposed, showing a level of stability to perturbations similar to the previous model, without any CPG components. Although exhibiting striking similarities with human gaits, the lack of CPG makes the control of speed/step length in the model difficult. In this paper, we hypothesize that a CPG component will offer a meaningful way of controlling the locomotion speed. After introducing the CPG component in the reflex model, and taking advantage of the resulting properties, a simple model for gait modulation is presented. The results highlight the advantages of a CPG as feedforward component in terms of gait modulation. PMID:25018712

The Contribution of a Central Pattern Generator in a Reflex-Based Neuromuscular Model

Directory of Open Access Journals (Sweden)

Florin eDzeladini

2014-06-01

Full Text Available Although the concept of central pattern generators (CPGs controlling locomotion in vertebrates is widely accepted, the presence of specialized CPGs in human locomotion is still a matter of debate. An interesting numerical model developed in the 90s' demonstrated the important role CPGs could play in human locomotion, both in terms of stability against perturbations, and in terms of speed control. Recently, a reflex-based neuro-musculo-skeletal model has been proposed, showing a level of stability to perturbations similar to the previous model, without any CPG components. Although exhibiting striking similarities with human gaits, the lack of CPG makes the control of speed/step length in the model difficult. In this paper, we hypothesize that a CPG component will offer a meaningful way of controlling the locomotion speed. After introducing the CPG component in the reflex model, and taking advantage of the resulting properties, a simple model for gait modulation is presented.The results highlight the advantages that a feedforward component can have in terms of gait modulation.

A central pattern generator producing alternative outputs: phase relations of leech heart motor neurons with respect to premotor synaptic input.

Science.gov (United States)

Norris, Brian J; Weaver, Adam L; Wenning, Angela; García, Paul S; Calabrese, Ronald L

2007-11-01

The central pattern generator (CPG) for heartbeat in leeches consists of seven identified pairs of segmental heart interneurons and one unidentified pair. Four of the identified pairs and the unidentified pair of interneurons make inhibitory synaptic connections with segmental heart motor neurons. The CPG produces a side-to-side asymmetric pattern of intersegmental coordination among ipsilateral premotor interneurons corresponding to a similarly asymmetric fictive motor pattern in heart motor neurons, and asymmetric constriction pattern of the two tubular hearts: synchronous and peristaltic. Using extracellular techniques, we recorded, in 61 isolated nerve cords, the activity of motor neurons in conjunction with the phase reference premotor heart interneuron, HN(4), and another premotor interneuron that allowed us to assess the coordination mode. These data were then coupled with a previous description of the temporal pattern of premotor interneuron activity in the two coordination modes to synthesize a global phase diagram for the known elements of the CPG and the entire motor neuron ensemble. These average data reveal the stereotypical side-to-side asymmetric patterns of intersegmental coordination among the motor neurons and show how this pattern meshes with the activity pattern of premotor interneurons. Analysis of animal-to-animal variability in this coordination indicates that the intersegmental phase progression of motor neuron activity in the midbody in the peristaltic coordination mode is the most stereotypical feature of the fictive motor pattern. Bilateral recordings from motor neurons corroborate the main features of the asymmetric motor pattern.

Apparatus for generating nonlinear pulse patterns

Science.gov (United States)

Nakamura, N.M.I.

Apparatus for generating a plurality of nonlinear pulse patterns from a single linear pulse pattern. A first counter counts the pulses of the linear pulse pattern and a second counter counts the pulses of the nonlinear pulse pattern. A comparator compares the counts of both counters, and in response to an equal count, a gate is enabled to gate a pulse of the linear pattern as a pulse of the nonlinear pattern, the latter also resetting the first counter. Presettable dividers divide the pulses of each pattern before they are counted by the respective counters. Apparatus for generating a logarithmic pulse pattern from a linear pulse pattern to any log base is described. In one embodiment, a shift register is used in place of the second counter to be clocked by each pulse of the logarithmic pattern to generate the pattern. In another embodiment, a memory stores the logarithmic pattern and is addressed by the second counter which is clocked by the pulses of the logarithmic pulse pattern.

Repetition priming of motor activity mediated by a central pattern generator: the importance of extrinsic vs. intrinsic program initiators

Science.gov (United States)

Siniscalchi, Michael J.; Jing, Jian; Weiss, Klaudiusz R.

2016-01-01

Repetition priming is characterized by increased performance as a behavior is repeated. Although this phenomenon is ubiquitous, mediating mechanisms are poorly understood. We address this issue in a model system, the feeding network of Aplysia. This network generates both ingestive and egestive motor programs. Previous data suggest a chemical coding model: ingestive and egestive inputs to the feeding central pattern generator (CPG) release different modulators, which act via different second messengers to prime motor activity in different ways. The ingestive input to the CPG (neuron CBI-2) releases the peptides feeding circuit activating peptide and cerebral peptide 2, which produce an ingestive pattern of activity. The egestive input to the CPG (the esophageal nerve) releases the peptide small cardioactive peptide. This model is based on research that focused on a single aspect of motor control (radula opening). Here we ask whether repetition priming is observed if activity is triggered with a neuron within the core CPG itself and demonstrate that it is not. Moreover, previous studies demonstrated that effects of modulatory neurotransmitters that induce repetition priming persist. This suggests that it should be possible to “prime” motor programs triggered from within the CPG by first stimulating extrinsic modulatory inputs. We demonstrate that programs triggered after ingestive input activation are ingestive and programs triggered after egestive input activation are egestive. We ask where this priming occurs and demonstrate modifications within the CPG itself. This arrangement is likely to have important consequences for “task” switching, i.e., the cessation of one type of motor activity and the initiation of another. PMID:27466134

Cellular basis for singing motor pattern generation in the field cricket (Gryllus bimaculatus DeGeer)

Science.gov (United States)

Schöneich, Stefan; Hedwig, Berthold

2012-01-01

The singing behavior of male crickets allows analyzing a central pattern generator (CPG) that was shaped by sexual selection for reliable production of species-specific communication signals. After localizing the essential ganglia for singing in Gryllus bimaculatus, we now studied the calling song CPG at the cellular level. Fictive singing was initiated by pharmacological brain stimulation. The motor pattern underlying syllables and chirps was recorded as alternating spike bursts of wing-opener and wing-closer motoneurons in a truncated wing nerve; it precisely reflected the natural calling song. During fictive singing, we intracellularly recorded and stained interneurons in thoracic and abdominal ganglia and tested their impact on the song pattern by intracellular current injections. We identified three interneurons of the metathoracic and first unfused abdominal ganglion that rhythmically de- and hyperpolarized in phase with the syllable pattern and spiked strictly before the wing-opener motoneurons. Depolarizing current injection in two of these opener interneurons caused additional rhythmic singing activity, which reliably reset the ongoing chirp rhythm. The closely intermeshing arborizations of the singing interneurons revealed the dorsal midline neuropiles of the metathoracic and three most anterior abdominal neuromeres as the anatomical location of singing pattern generation. In the same neuropiles, we also recorded several closer interneurons that rhythmically hyper- and depolarized in the syllable rhythm and spiked strictly before the wing-closer motoneurons. Some of them received pronounced inhibition at the beginning of each chirp. Hyperpolarizing current injection in the dendrite revealed postinhibitory rebound depolarization as one functional mechanism of central pattern generation in singing crickets. PMID:23170234

Some economic effects of recent migration patterns on central cities.

Science.gov (United States)

Sternlieb, G; Hughes, J W

1981-01-01

The authors examine demographic changes in central cities of the United States between 1970 and 1977 and the economic effects of these changes. Patterns of selective migration from central cities, particularly the general out-migration of the middle class and the recent return of the middle class to selected areas, are discussed. Changes in household and family patterns, racial composition, income, and poverty status are examined, and the aggregate impact of migration on resident incomes and purchasing power within central cities is analyzed. The findings show a continued concentration of poverty in central cities.

Genetic control of a central pattern generator: rhythmic oromotor movement in mice is controlled by a major locus near Atp1a2.

Directory of Open Access Journals (Sweden)

John D Boughter

Full Text Available Fluid licking in mice is a rhythmic behavior that is controlled by a central pattern generator (CPG located in a complex of brainstem nuclei. C57BL/6J (B6 and DBA/2J (D2 strains differ significantly in water-restricted licking, with a highly heritable difference in rates (h(2≥0.62 and a corresponding 20% difference in interlick interval (mean ± SEM = 116.3±1 vs 95.4±1.1 ms. We systematically quantified motor output in these strains, their F(1 hybrids, and a set of 64 BXD progeny strains. The mean primary interlick interval (MPI varied continuously among progeny strains. We detected a significant quantitative trait locus (QTL for a CPG controlling lick rate on Chr 1 (Lick1, and a suggestive locus on Chr 10 (Lick10. Linkage was verified by testing of B6.D2-1D congenic stock in which a segment of Chr 1 of the D2 strain was introgressed onto the B6 parent. The Lick1 interval on distal Chr 1 contains several strong candidate genes. One of these is a sodium/potassium pump subunit (Atp1a2 with widespread expression in astrocytes, as well as in a restricted population of neurons. Both this subunit and the entire Na(+/K(+-ATPase molecule have been implicated in rhythmogenesis for respiration and locomotion. Sequence variants in or near Apt1a2 strongly modulate expression of the cognate mRNA in multiple brain regions. This gene region has recently been sequenced exhaustively and we have cataloged over 300 non-coding and synonymous mutations segregating among BXD strains, one or more of which is likely to contribute to differences in central pattern generator tempo.

Comparison of extrinsic and intrinsic neuromodulation in two central pattern generator circuits in invertebrates.

Science.gov (United States)

Katz, P S

1998-05-01

There are many sources of modulatory input to CPGs and other types of neuronal circuits. These inputs can change the properties of cells and synapses and dramatically alter the production of motor patterns. Sometimes this enables the production of motor patterns by the circuit. At other times, the modulation allows alternate motor patterns to be produced by a single circuit. Modulatory neurones have fast as well as slow actions. In some cases, such as with GPR, the two types of effects are due to the release of co-transmitters. In other cases, such as with the DSIs, a single substance can act at different receptors to cause fast and slow postsynaptic actions. The effect of a neuromodulatory neurone is determined by the type of receptor on the target neurone. Thus a single modulatory neurone evokes a suite of actions in a circuit and thereby produces a co-ordinated output. Extrinsic and intrinsic sources of neuromodulation have different sets of constraints acting upon them. For example, extrinsic neuromodulation can easily be used for motor pattern selection; a different pattern is produced depending upon which modulatory inputs are active. However, intrinsic neuromodulation is not well suited to that task. Instead, it is useful for self-organizing properties and experience-dependent effects. One clear conclusion from this work and other work in the field is that neuromodulation by neurones intrinsic and extrinsic to CPGs is not uncommon (Katz, 1995; Katz & Frost, 1996). It is part of the normal process of motor pattern generation. As such, it needs to be considered when discussing mechanisms for neuronal circuit actions.

Bio-inspired control of joint torque and knee stiffness in a robotic lower limb exoskeleton using a central pattern generator.

Science.gov (United States)

Schrade, Stefan O; Nager, Yannik; Wu, Amy R; Gassert, Roger; Ijspeert, Auke

2017-07-01

Robotic lower limb exoskeletons are becoming increasingly popular in therapy and recreational use. However, most exoskeletons are still rather limited in their locomotion speed and the activities of daily live they can perform. Furthermore, they typically do not allow for a dynamic adaptation to the environment, as they are often controlled with predefined reference trajectories. Inspired by human leg stiffness modulation during walking, variable stiffness actuators increase flexibility without the need for more complex controllers. Actuation with adaptable stiffness is inspired by the human leg stiffness modulation during walking. However, this actuation principle also introduces the stiffness setpoint as an additional degree of freedom that needs to be coordinated with the joint trajectories. As a potential solution to this issue a bio-inspired controller based on a central pattern generator (CPG) is presented in this work. It generates coordinated joint torques and knee stiffness modulations to produce flexible and dynamic gait patterns for an exoskeleton with variable knee stiffness actuation. The CPG controller is evaluated and optimized in simulation using a model of the exoskeleton. The CPG controller produced stable and smooth gait for walking speeds from 0.4 m/s up to 1.57 m/s with a torso stabilizing force that simulated the use of crutches, which are commonly needed by exoskeleton users. Through the CPG, the knee stiffness intrinsically adapted to the frequency and phase of the gait, when the speed was changed. Additionally, it adjusted to changes in the environment in the form of uneven terrain by reacting to ground contact forces. This could allow future exoskeletons to be more adaptive to various environments, thus making ambulation more robust.

A novel approach to locomotion learning: Actor-Critic architecture using central pattern generators and dynamic motor primitives.

Science.gov (United States)

Li, Cai; Lowe, Robert; Ziemke, Tom

2014-01-01

In this article, we propose an architecture of a bio-inspired controller that addresses the problem of learning different locomotion gaits for different robot morphologies. The modeling objective is split into two: baseline motion modeling and dynamics adaptation. Baseline motion modeling aims to achieve fundamental functions of a certain type of locomotion and dynamics adaptation provides a "reshaping" function for adapting the baseline motion to desired motion. Based on this assumption, a three-layer architecture is developed using central pattern generators (CPGs, a bio-inspired locomotor center for the baseline motion) and dynamic motor primitives (DMPs, a model with universal "reshaping" functions). In this article, we use this architecture with the actor-critic algorithms for finding a good "reshaping" function. In order to demonstrate the learning power of the actor-critic based architecture, we tested it on two experiments: (1) learning to crawl on a humanoid and, (2) learning to gallop on a puppy robot. Two types of actor-critic algorithms (policy search and policy gradient) are compared in order to evaluate the advantages and disadvantages of different actor-critic based learning algorithms for different morphologies. Finally, based on the analysis of the experimental results, a generic view/architecture for locomotion learning is discussed in the conclusion.

A Novel Approach to Locomotion Learning: Actor-Critic Architecture using Central Pattern Generators and Dynamic Motor Primitives

Directory of Open Access Journals (Sweden)

Cai eLi

2014-10-01

Full Text Available In this article, we propose an architecture of a bio-inspired controller that addresses the problem of learning different locomotion gaits for different robot morphologies. The modelling objective is split into two: baseline motion modelling and dynamics adaptation. Baseline motion modelling aims to achieve fundamental functions of a certain type of locomotion and dynamics adaptation provides a ``reshaping function for adapting the baseline motion to desired motion. Based on this assumption, a three-layer architecture is developed using central pattern generators (CPGs, a bio-inspired locomotor center for the the baseline motion and dynamic motor primitives (DMPs, a model with universal ``reshaping functions. In this article, we use this architecture with the actor-critic algorithms for finding a good ``reshaping function. In order to demonstrate the learning power of the actor-critic based architecture, we tested it on two experiments: 1 learning to crawl on a humanoid and, 2 learning to gallop on a puppy robot. Two types of actor-critic algorithms (policy search and policy gradient are compared in order to evaluate the advantages and disadvantages of different actor-critic based learning algorithms for different morphologies. Finally, based on the analysis of the experimental results, a generic view/architecture for locomotion learning is discussed in the conclusion.

Generation and Analysis of Constrained Random Sampling Patterns

DEFF Research Database (Denmark)

Pierzchlewski, Jacek; Arildsen, Thomas

2016-01-01

Random sampling is a technique for signal acquisition which is gaining popularity in practical signal processing systems. Nowadays, event-driven analog-to-digital converters make random sampling feasible in practical applications. A process of random sampling is defined by a sampling pattern, which...... indicates signal sampling points in time. Practical random sampling patterns are constrained by ADC characteristics and application requirements. In this paper, we introduce statistical methods which evaluate random sampling pattern generators with emphasis on practical applications. Furthermore, we propose...... algorithm generates random sampling patterns dedicated for event-driven-ADCs better than existed sampling pattern generators. Finally, implementation issues of random sampling patterns are discussed....

Cultured embryonic non-innervated mouse muzzle is capable of generating a whisker pattern.

Science.gov (United States)

Andrés, F L; Van Der Loos, H

1983-01-01

The whisker pattern on the muzzle of the mouse is mapped in the contralateral parietal neocortex, each whisker follicle projecting to its own multineuronal unit ('barrel'). To determine the role, if any, of the peripheral innervation in the establishment of the vibrissal array, we cultured non-innervated prospective whiskerpads from 9- and 10-day-old embryos, mostly on chorioallantoic membrane. The results show that skin, alone, is capable of generating the whisker pattern, thus adducing a strong argument for the hypothesis that the central brain maps have their origin in the periphery. Copyright © 1983. Published by Elsevier Ltd.

Bidirectional plasticity of pontine pneumotaxic postinspiratory drive: implication for a pontomedullary respiratory central pattern generator.

Science.gov (United States)

Poon, Chi-Sang; Song, Gang

2014-01-01

The "pneumotaxic center" in the rostral dorsolateral pons as delineated by Lumsden nine decades ago is known to play an important role in promoting the inspiratory off-switch (IOS) for inspiratory-expiratory phase transition as a fail-safe mechanism for preventing apneusis in the absence of vagal input. Traditionally, the pontine pneumotaxic mechanism has been thought to contribute a tonic descending input that lowers the IOS threshold in medullary respiratory central pattern generator (rCPG) circuits, but otherwise does not constitute part of the rCPG. Recent evidence indicates that descending input from the Kölliker-Fuse nucleus (KFN) within the pneumotaxic center is essential for gating the postinspiratory phase of the three-phase respiratory rhythm to control the IOS in vagotomized animals. A critical question arising is whether such a descending pneumotaxic input from KFN that drives postinspiratory activity is tonic (null hypothesis) or rhythmic with postinspiratory phase modulation (alternative hypothesis). Here, we show that multifarious evidence reported in the literature collectively indicates that the descending pneumotaxic input may exhibit NMDA receptor-dependent short-term plasticity in the form of a biphasic neural differentiator that bidirectionally and phase-selectively modulates postinspiratory phase duration in response to vagal and peripheral chemoreceptor inputs independent of the responses in inspiratory and late-expiratory activities. The phase-selectivity property of the descending pneumotaxic input implicates a population of pontine early-expiratory (postinspiratory/expiratory-decrementing) neurons as the most likely neural correlate of the pneumotaxic mechanism that drives post-I activity, suggesting that the pontine pneumotaxic mechanism may be an integral part of a pontomedullary rCPG that underlies the three-phase respiratory rhythm. © 2014 Elsevier B.V. All rights reserved.

Rapid recovery and altered neurochemical dependence of locomotor central pattern generation following lumbar neonatal spinal cord injury.

Science.gov (United States)

Züchner, Mark; Kondratskaya, Elena; Sylte, Camilla B; Glover, Joel C; Boulland, Jean-Luc

2018-01-15

Spinal compression injury targeted to the neonatal upper lumbar spinal cord, the region of highest hindlimb locomotor rhythmogenicity, leads to an initial paralysis of the hindlimbs. Behavioural recovery is evident within a few days and approaches normal function within about 3 weeks. Fictive locomotion in the isolated injured spinal cord cannot be elicited by a neurochemical cocktail containing NMDA, dopamine and serotonin 1 day post-injury, but can 3 days post-injury as readily as in the uninjured spinal cord. Low frequency coordinated rhythmic activity can be elicited in the isolated uninjured spinal cord by NMDA + dopamine (without serotonin), but not in the isolated injured spinal cord. In both the injured and uninjured spinal cord, eliciting bona fide fictive locomotion requires the additional presence of serotonin. Following incomplete compression injury in the thoracic spinal cord of neonatal mice 1 day after birth (P1), we previously reported that virtually normal hindlimb locomotor function is recovered within about 3 weeks despite substantial permanent thoracic tissue loss. Here, we asked whether similar recovery occurs following lumbar injury that impacts more directly on the locomotor central pattern generator (CPG). As in thoracic injuries, lumbar injuries caused about 90% neuronal loss at the injury site and increased serotonergic innervation below the injury. Motor recovery was slower after lumbar than thoracic injury, but virtually normal function was attained by P25 in both cases. Locomotor CPG status was tested by eliciting fictive locomotion in isolated spinal cords using a widely used neurochemical cocktail (NMDA, dopamine, serotonin). No fictive locomotion could be elicited 1 day post-injury, but could within 3 days post-injury as readily as in age-matched uninjured control spinal cords. Burst patterning and coordination were largely similar in injured and control spinal cords but there were differences. Notably, in both groups there

Test Pattern Generator for Mixed Mode BIST

Energy Technology Data Exchange (ETDEWEB)

Kim, Hong Sik; Lee, Hang Kyu; Kang, Sung Ho [Yonsei University (Korea, Republic of)

1998-07-01

As the increasing integrity of VLSI, the BIST (Built-In Self Test) is used as an effective method to test chips. Generally the pseudo-random test pattern generation is used for BIST. But it requires lots of test patterns when there exist random resistant faults. Therefore deterministic testing is an interesting BIST technique due to the minimal number of test patterns and to its high fault coverage. However this is not applicable since the existing deterministic test pattern generators require too much area overhead despite their efficiency. Therefore we propose a mixed test scheme which applies to the circuit under test, a deterministic test sequence followed by a pseudo-random one. This scheme allows the maximum fault coverage detection to be achieved, furthermore the silicon area overhead of the mixed hardware generator can be reduced. The deterministic test generator is made with a finite state machine and a pseudo-random test generator is made with LFSR(linear feedback shift register). The results of ISCAS circuits show that the maximum fault coverage is guaranteed with small number of test set and little hardware overhead. (author). 15 refs., 10 figs., 4 tabs.

Modeling urbanization patterns with generative adversarial networks

OpenAIRE

Albert, Adrian; Strano, Emanuele; Kaur, Jasleen; Gonzalez, Marta

2018-01-01

In this study we propose a new method to simulate hyper-realistic urban patterns using Generative Adversarial Networks trained with a global urban land-use inventory. We generated a synthetic urban "universe" that qualitatively reproduces the complex spatial organization observed in global urban patterns, while being able to quantitatively recover certain key high-level urban spatial metrics.

Neuronal activity in the isolated mouse spinal cord during spontaneous deletions in fictive locomotion: insights into locomotor central pattern generator organization

Science.gov (United States)

Zhong, Guisheng; Shevtsova, Natalia A; Rybak, Ilya A; Harris-Warrick, Ronald M

2012-01-01

We explored the organization of the spinal central pattern generator (CPG) for locomotion by analysing the activity of spinal interneurons and motoneurons during spontaneous deletions occurring during fictive locomotion in the isolated neonatal mouse spinal cord, following earlier work on locomotor deletions in the cat. In the isolated mouse spinal cord, most spontaneous deletions were non-resetting, with rhythmic activity resuming after an integer number of cycles. Flexor and extensor deletions showed marked asymmetry: flexor deletions were accompanied by sustained ipsilateral extensor activity, whereas rhythmic flexor bursting was not perturbed during extensor deletions. Rhythmic activity on one side of the cord was not perturbed during non-resetting spontaneous deletions on the other side, and these deletions could occur with no input from the other side of the cord. These results suggest that the locomotor CPG has a two-level organization with rhythm-generating (RG) and pattern-forming (PF) networks, in which only the flexor RG network is intrinsically rhythmic. To further explore the neuronal organization of the CPG, we monitored activity of motoneurons and selected identified interneurons during spontaneous non-resetting deletions. Motoneurons lost rhythmic synaptic drive during ipsilateral deletions. Flexor-related commissural interneurons continued to fire rhythmically during non-resetting ipsilateral flexor deletions. Deletion analysis revealed two classes of rhythmic V2a interneurons. Type I V2a interneurons retained rhythmic synaptic drive and firing during ipsilateral motor deletions, while type II V2a interneurons lost rhythmic synaptic input and fell silent during deletions. This suggests that the type I neurons are components of the RG, whereas the type II neurons are components of the PF network. We propose a computational model of the spinal locomotor CPG that reproduces our experimental results. The results may provide novel insights into the

Fringe patterns generated by micro-optical sensors for pattern recognition.

Science.gov (United States)

Tamee, Kreangsak; Chaiwong, Khomyuth; Yothapakdee, Kriengsak; Yupapin, Preecha P

2015-01-01

We present a new result of pattern recognition generation scheme using a small-scale optical muscle sensing system, which consisted of an optical add-drop filter incorporating two nonlinear optical side ring resonators. When light from laser source enters into the system, the device is stimulated by an external physical parameter that introduces a change in the phase of light propagation within the sensing device, which can be formed by the interference fringe patterns. Results obtained have shown that the fringe patterns can be used to form the relationship between signal patterns and fringe pattern recognitions.

Computer generated holography with intensity-graded patterns

Directory of Open Access Journals (Sweden)

Rossella Conti

2016-10-01

Full Text Available Computer Generated Holography achieves patterned illumination at the sample plane through phase modulation of the laser beam at the objective back aperture. This is obtained by using liquid crystal-based spatial light modulators (LC-SLMs, which modulate the spatial phase of the incident laser beam. A variety of algorithms are employed to calculate the phase modulation masks addressed to the LC-SLM. These algorithms range from simple gratings-and-lenses to generate multiple diffraction-limited spots, to iterative Fourier-transform algorithms capable of generating arbitrary illumination shapes perfectly tailored on the base of the target contour. Applications for holographic light patterning include multi-trap optical tweezers, patterned voltage imaging and optical control of neuronal excitation using uncaging or optogenetics. These past implementations of computer generated holography used binary input profile to generate binary light distribution at the sample plane. Here we demonstrate that using graded input sources, enables generating intensity graded light patterns and extend the range of application of holographic light illumination. At first, we use intensity-graded holograms to compensate for LC-SLM position dependent diffraction efficiency or sample fluorescence inhomogeneity. Finally we show that intensity-graded holography can be used to equalize photo evoked currents from cells expressing different level of chanelrhodopsin2 (ChR2, one of the most commonly used optogenetics light gated channels, taking into account the non-linear dependence of channel opening on incident light.

Pattern of Bone Generation after Irradiation in Vascularized Tissue Engineered Constructs.

Science.gov (United States)

Eweida, Ahmad; Fathi, Ibrahim; Eltawila, Ahmed M; Elsherif, Ahmad M; Elkerm, Yasser; Harhaus, Leila; Kneser, Ulrich; Sakr, Mahmoud F

2018-02-01

 Regenerative medicine modalities provide promising alternatives to conventional reconstruction techniques but are still deficient after malignant tumor excision or irradiation due to defective vascularization.  We investigated the pattern of bone formation in axially vascularized tissue engineering constructs (AVTECs) after irradiation in a study that mimics the clinical scenario after head and neck cancer. Heterotopic bone generation was induced in a subcutaneously implanted AVTEC in the thigh of six male New Zealand rabbits. The tissue construct was made up of Nanobone (Artoss GmbH; Rostock, Germany) granules mixed with autogenous bone marrow and 80 μL of bone morphogenic protein-2 at a concentration of 1.5 μg/μL. An arteriovenous loop was created microsurgically between the saphenous vessels and implanted in the core of the construct to induce axial vascularization. The constructs were subjected to external beam irradiation on postoperative day 20 with a single dose of 15 Gy. The constructs were removed 20 days after irradiation and subjected to histological and immunohistochemical analysis for vascularization, bone formation, apoptosis, and cellular proliferation.  The vascularized constructs showed homogenous vascularization and bone formation both in their central and peripheral regions. Although vascularity, proliferation, and apoptosis were similar between central and peripheral regions of the constructs, significantly more bone was formed in the central regions of the constructs.  The study shows for the first time the pattern of bone formation in AVTECs after irradiation using doses comparable to those applied after head and neck cancer. Axial vascularization probably enhances the osteoinductive properties in the central regions of AVTECs after irradiation. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Generating spatiotemporal joint torque patterns from dynamical synchronization of distributed pattern generators

Directory of Open Access Journals (Sweden)

Alex Pitti

2009-10-01

Full Text Available Pattern generators found in the spinal cords are no more seen as simple rhythmic oscillators for motion control. Indeed, they achieve flexible and dynamical coordination in interaction with the body and the environment dynamics to rise motor synergies. Discovering the mechanisms underlying the control of motor synergies constitute an important research question not only for neuroscience but also for robotics: the motors coordination of high dimensional robotic systems is still a drawback and new control methods based on biological solutions may reduce their overall complexity. We propose to model the flexible combination of motor synergies in embodied systems via partial phase synchronization of distributed chaotic systems; for specific coupling strength, chaotic systems are able to phase synchronize their dynamics to the resonant frequencies of one external force. We take advantage of this property to explore and exploit the intrinsic dynamics of one specified embodied system. In two experiments with bipedal walkers, we show how motor synergies emerge when the controllers phase synchronize to the body’s dynamics, entraining it to its intrinsic behavioral patterns. This stage is characterized by directed information flow from the sensors to the motors exhibiting the optimal situation when the body dynamics drive the controllers (mutual entrainment. Based on our results, we discuss the relevance of our findings for modeling the modular control of distributed pattern generators exhibited in the spinal cords, and for exploring the motor synergies in robots.

The central government power generating capacity- reforms and the future

International Nuclear Information System (INIS)

Singh, Rajendra

1995-01-01

The alarming resource gap that the states were facing in 1970's has prompted the Central Government to augment the resources for power generation by creating two new entities in November 1975 viz the National Thermal Power Corporation (NTPC) and National Hydro Power Corporation (NHPC). Few other organisations also exist in central sector which are engaged in power generation like Nuclear Power Corporation (NPC). NTPC being the leading player in the power sector, it can neither be indifferent nor dissociate itself from the reforms sweeping the sector today. The article describes the Central Government's role in power generation, reforms and NTPC and further prospects of NTPC

Meal patterns and cooking practices in Southern France and Central England.

Science.gov (United States)

Pettinger, Clare; Holdsworth, Michelle; Gerber, Mariette

2006-12-01

To evaluate whether meal patterns and cooking practices in Central England and Mediterranean France conform to popular stereotypes, eating together as a household, preparation of meals, food purchasing patterns, cooking practices and eating out were investigated. Cross-sectional studies conducted simultaneously in April 2001 using self-administered postal questionnaires. England (Nottingham, East Midlands) and France (Montpellier, Languedoc-Roussillon). A stratified random sample of 1000 males and 1000 females aged 18-65 years was generated from the electoral roll in each country. The final sample comprised 826 subjects in England (58% males, 42% females; mean age 44 years) and 766 subjects in France (42% males, 58% females; mean age 42 years). Analyses were conducted on samples standardised for sociodemographic differences. The French cooked from raw ingredients most often (PFrench and English food cultures, as the importance of the convivial aspects of eating, as well as more traditional practices such as cooking meals from basic ingredients, structured mealtimes and less between-meal snacking, remain more prominent within the French population. This may contribute to the differences in prevalence of obesity seen between the two countries.

Programmable pseudo-random detector-pulse-pattern generator

International Nuclear Information System (INIS)

Putten, R. van der; Nationaal Inst. voor Kernfysica en Hoge-Energiefysica

1990-01-01

This report discusses the design and realization of the digital part of the programmable pseudo-random detector pulse-pattern generator. For the design and realization use has been made of F-TTL and high speed special purpose ic's, in particular FAL's (15 ns). The design possibilities offered by the software for pro-gramming of the FAL's have been utilized as much as possible. In this way counters, registers and a state machine with extended control possibilities have been designed and an advanced 8 channel pulse generator has been developed which is controlled via the VME system bus. the generator possesses an internal clock oscillator of 16 MHZ. The moment when a pulse is generated can be adjusted with a step size of 250 ps. 2000 different periods (time windows) can be stored for generating a pattern. (author). 37 refs.; 6 figs

Generation Y Online Buying Patterns

OpenAIRE

Katija Vojvodić; Matea Matić

2015-01-01

The advantages of electronic retailing can, among other things, result in uncontrolled buying by online consumers, i.e. in extreme buying behavior. The main purpose of this paper is to analyze and determine the buying patterns of Generation Y online consumers in order to explore the existence of different types of behavior based on the characteristics of online buying. The paper also aims at exploring the relationship between extracted factors and Generation Y consumers’ buying intentions. Em...

Roles for multifunctional and specialized spinal interneurons during motor pattern generation in tadpoles, zebrafish larvae, and turtles

Directory of Open Access Journals (Sweden)

Ari Berkowitz

2010-06-01

Full Text Available The hindbrain and spinal cord can produce multiple forms of locomotion, escape, and withdrawal behaviors and (in limbed vertebrates site-specific scratching. Until recently, the prevailing view was that the same classes of CNS neurons generate multiple kinds of movements, either through reconfiguration of a single, shared network or through an increase in the number of neurons recruited within each class. The mechanisms involved in selecting and generating different motor patterns have recently been explored in detail in some non-mammalian, vertebrate model systems. Work on the hatchling Xenopus tadpole, the larval zebrafish, and the adult turtle has now revealed that distinct kinds of motor patterns are actually selected and generated by combinations of multifunctional and specialized spinal interneurons. Multifunctional interneurons may form a core, multipurpose circuit that generates elements of coordinated motor output utilized in multiple behaviors, such as left-right alternation. But, in addition, specialized spinal interneurons including separate glutamatergic and glycinergic classes are selectively activated during specific patterns: escape-withdrawal, swimming and struggling in tadpoles and zebrafish, and limb withdrawal and scratching in turtles. These specialized neurons can contribute by changing the way central pattern generator (CPG activity is initiated and by altering CPG composition and operation. The combined use of multifunctional and specialized neurons is now established as a principle of organization across a range of vertebrates. Future research may reveal common patterns of multifunctionality and specialization among interneurons controlling diverse movements and whether similar mechanisms exist in higher-order brain circuits that select among a wider array of complex movements.

Procedural generation of aesthetic patterns from dynamics and iteration processes

Directory of Open Access Journals (Sweden)

Gdawiec Krzysztof

2017-12-01

Full Text Available Aesthetic patterns are widely used nowadays, e.g., in jewellery design, carpet design, as textures and patterns on wallpapers, etc. Most of the work during the design stage is carried out by a designer manually. Therefore, it is highly useful to develop methods for aesthetic pattern generation. In this paper, we present methods for generating aesthetic patterns using the dynamics of a discrete dynamical system. The presented methods are based on the use of various iteration processes from fixed point theory (Mann, S, Noor, etc. and the application of an affine combination of these iterations. Moreover, we propose new convergence tests that enrich the obtained patterns. The proposed methods generate patterns in a procedural way and can be easily implemented on the GPU. The presented examples show that using the proposed methods we are able to obtain a variety of interesting patterns. Moreover, the numerical examples show that the use of the GPU implementation with shaders allows the generation of patterns in real time and the speed-up (compared with a CPU implementation ranges from about 1000 to 2500 times.

A model-based exploration of the role of pattern generating circuits during locomotor adaptation.

Science.gov (United States)

Marjaninejad, Ali; Finley, James M

2016-08-01

In this study, we used a model-based approach to explore the potential contributions of central pattern generating circuits (CPGs) during adaptation to external perturbations during locomotion. We constructed a neuromechanical modeled of locomotion using a reduced-phase CPG controller and an inverted pendulum mechanical model. Two different forms of locomotor adaptation were examined in this study: split-belt treadmill adaptation and adaptation to a unilateral, elastic force field. For each simulation, we first examined the effects of phase resetting and varying the model's initial conditions on the resulting adaptation. After evaluating the effect of phase resetting on the adaptation of step length symmetry, we examined the extent to which the results from these simple models could explain previous experimental observations. We found that adaptation of step length symmetry during split-belt treadmill walking could be reproduced using our model, but this model failed to replicate patterns of adaptation observed in response to force field perturbations. Given that spinal animal models can adapt to both of these types of perturbations, our findings suggest that there may be distinct features of pattern generating circuits that mediate each form of adaptation.

Cytomegalovirus pneumonitis complicated by a central peribronchial pattern of organising pneumonia.

Science.gov (United States)

Cuadrado, Maria M; Ahmed, Asia; Carpenter, Ben; Brown, Jeremy S

2017-01-01

We present five cases of cytomegalovirus (CMV) pneumonitis occurring in patients after recent T cell deplete allogeneic stem cell transplantation (AlloHSCT). These cases were complicated by an organising pneumonia (during the recovery period) with a predominantly central peribronchial pattern. All patients presented with evidence of active CMV pneumonitis which was treated successfully with anti-viral therapy but was followed by persistent severe dyspnoea, cough and hypoxia. High resolution computed tomography (HRCT) imaging showed widespread central peribronchial consolidation with traction bronchiectasis. There was a marked clinical and physiological improvement after treatment with systemic corticosteroids. However, in all patients the lung function remained abnormal and in some cases imaging revealed a fibrosing lung disease. These cases represent a previously undescribed central peribronchial pattern of organising pneumonia complicating CMV pneumonitis that can result in chronic lung damage.

Airflow Pattern Generated by Three Air Diffusers

DEFF Research Database (Denmark)

Olmedo, Inés; Nielsen, Peter V.; Ruiz de Adana, Manuel

2011-01-01

The correct description of air diffusers plays a crucial role in the CFD predictions of the airflow pattern into a room. The numerical simulation of air distribution in an indoor space is challenging because of the complicated airflow pattern generated. Many authors have developed simplified geom...

Generative models versus underlying symmetries to explain biological pattern.

Science.gov (United States)

Frank, S A

2014-06-01

Mathematical models play an increasingly important role in the interpretation of biological experiments. Studies often present a model that generates the observations, connecting hypothesized process to an observed pattern. Such generative models confirm the plausibility of an explanation and make testable hypotheses for further experiments. However, studies rarely consider the broad family of alternative models that match the same observed pattern. The symmetries that define the broad class of matching models are in fact the only aspects of information truly revealed by observed pattern. Commonly observed patterns derive from simple underlying symmetries. This article illustrates the problem by showing the symmetry associated with the observed rate of increase in fitness in a constant environment. That underlying symmetry reveals how each particular generative model defines a single example within the broad class of matching models. Further progress on the relation between pattern and process requires deeper consideration of the underlying symmetries. © 2014 The Author. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Generation Y Online Buying Patterns

Directory of Open Access Journals (Sweden)

Katija Vojvodić

2015-12-01

Full Text Available The advantages of electronic retailing can, among other things, result in uncontrolled buying by online consumers, i.e. in extreme buying behavior. The main purpose of this paper is to analyze and determine the buying patterns of Generation Y online consumers in order to explore the existence of different types of behavior based on the characteristics of online buying. The paper also aims at exploring the relationship between extracted factors and Generation Y consumers’ buying intentions. Empirical research was conducted on a sample of 515 consumers in the Dubrovnik-Neretva County. Based on the factor analysis, research results indicate that Generation Y online consumers are influenced by three factors: compulsivity, impulsivity, and functionality. The analysis of variance reveals that significant differences exist between the extracted factors and Generation Y’s online buying characteristics. In addition, correlation analysis shows a statistically significant correlation between the extracted factors and Generation Y’s buying intentions.

Bending patterns of chlamydomonas flagella: III. A radial spoke head deficient mutant and a central pair deficient mutant.

Science.gov (United States)

Brokaw, C J; Luck, D J

1985-01-01

Flash photomicrography at frequencies up to 300 Hz and computer-assisted image analysis have been used to obtain parameters describing the flagellar bending patterns of mutants of Chlamydomonas reinhardtii. All strains contained the uni1 mutation, to facilitate photography. The radial spoke head deficient mutant pf17, and the central pair deficient mutant, pf15, in combination with suppressor mutations that restore motility without restoring the ultrastructural or biochemical deficiencies, both generate forward mode bending patterns with increased shear amplitude and decreased asymmetry relative to the "wild-type" uni1 flagella described previously. In the reverse beating mode, the suppressed pf17 mutants generate reverse bending patterns with large shear amplitudes. Reverse beating of the suppressed pf15 mutants is rare. There is a reciprocal relationship between increased shear amplitude and decreased beat frequency, so that the velocity of sliding between flagellar microtubules is not increased by an increase in shear amplitude. The suppressor mutations alone cause decreased frequency and sliding velocity in both forward and reverse mode beating, with little change in shear amplitude or symmetry.

On the generation of coastal lows in central Chile

International Nuclear Information System (INIS)

Rutllant, J.

1994-07-01

Previous studies of the coastal-low occurrences in central Chile have been aimed at the formulation of a conceptual model to explain observed features in connection with applied studies. The most prominent weather pattern associated with CL occurrences, (type A), coincides with the onset of a warm, middle-troposphere ridge over central Chile, and a surface high over northern Argentina. The synoptic forcing of the low is related to weak frontal disturbances that travel equatorwards. They result in a thickening of the marine layer that becomes blocked by the coastal escarpment, at the time of the onset of the ridge aloft. The blocking of the stable air above the subsidence inversion by the Andes is also hypothesized. The analysis of the subsidence inversion, the geometry of the coastal and Andes mountain ranges, and a scale analysis of the non-dimensional governing equations for the generation of the coastal lows, following the approach of Reason and Steyn (1990); leads to the conclusion that both blocking actions are strong and persistent in central Chile. An interactive mechanism between the upper and lower blocking effects is postulated to explain the cyclonic vorticity and the initial steering of the coastal lows. The scale analysis of the governing equations for the propagation stage of the low suggests that, departing for the South African case, non-linearity is important here, and that solitary Kelvin waves could be expected. Theoretical phase propagation speeds and Rossby radii are found to range between 8 and 15 m s-1 and 100-250 km, respectively. The importance of strong southerly winds ahead of the low and weak winds at its trailing edge is also stressed, as another major departure from the coastal-low behaviour elsewhere. (author). 17 refs, 4 figs, 4 tabs

Phytochemical pattern of Gentiana species of Appennino in central Italy.

Science.gov (United States)

Venditti, A; Guarcini, L; Altieri, A; Bianco, A

2013-01-01

The molecular pattern of two Gentiana species, G. dinarica and G. lutea, present in a protected area of Appennino Centrale in Italy, was examined. Results were compared with literature data, examining the differences between the two species.

Centralized electricity generation in offshore wind farms using hydraulic networks

NARCIS (Netherlands)

Jarquin Laguna, A.

2017-01-01

The work presented in this thesis explores a new way of generation, collection and transmission of wind energy inside a wind farm, in which the electrical conversion does not occur during any intermediate conversion step before the energy has reached the offshore central platform. A centralized

Meal patterns and cooking practices in Southern France and Central England

OpenAIRE

Pettinger, C.; Holdsworth, Michelle; Gerber, M.

2006-01-01

Objective: To evaluate whether meal patterns and cooking practices in Central England and Mediterranean France conform to popular stereotypes, eating together as a household, preparation of meals, food purchasing patterns, cooking practices and eating out were investigated. Design: Cross-sectional studies conducted simultaneously in April 2001 using self-administered postal questionnaires. Setting: England (Nottingham, East Midlands) and France (Montpellier, Languedoc-Roussillon). Subjects: A...

Single-unit pattern generators for quadruped locomotion

DEFF Research Database (Denmark)

Morse, Gregory; Risi, Sebastian; Snyder, Charles R

2013-01-01

Legged robots can potentially venture beyond the limits of wheeled vehicles. While creating controllers for such robots by hand is possible, evolutionary algorithms are an alternative that can reduce the burden of hand-crafting robotic controllers. Although major evolutionary approaches to legged...... on a new type of neuron called a single-unit pattern generator (SUPG). The SUPG, which is indirectly encoded by a compositional pattern producing network (CPPN) evolved by HyperNEAT, produces a flexible temporal activation pattern that can be reset and repeated at any time through an explicit trigger input...

Generation of Customizable Micro-wavy Pattern through Grayscale Direct Image Lithography.

Science.gov (United States)

He, Ran; Wang, Shunqiang; Andrews, Geoffrey; Shi, Wentao; Liu, Yaling

2016-02-23

With the increasing amount of research work in surface studies, a more effective method of producing patterned microstructures is highly desired due to the geometric limitations and complex fabricating process of current techniques. This paper presents an efficient and cost-effective method to generate customizable micro-wavy pattern using direct image lithography. This method utilizes a grayscale Gaussian distribution effect to model inaccuracies inherent in the polymerization process, which are normally regarded as trivial matters or errors. The measured surface profiles and the mathematical prediction show a good agreement, demonstrating the ability of this method to generate wavy patterns with precisely controlled features. An accurate pattern can be generated with customizable parameters (wavelength, amplitude, wave shape, pattern profile, and overall dimension). This mask-free photolithography approach provides a rapid fabrication method that is capable of generating complex and non-uniform 3D wavy patterns with the wavelength ranging from 12 μm to 2100 μm and an amplitude-to-wavelength ratio as large as 300%. Microfluidic devices with pure wavy and wavy-herringbone patterns suitable for capture of circulating tumor cells are made as a demonstrative application. A completely customized microfluidic device with wavy patterns can be created within a few hours without access to clean room or commercial photolithography equipment.

Generation of Customizable Micro-wavy Pattern through Grayscale Direct Image Lithography

Science.gov (United States)

He, Ran; Wang, Shunqiang; Andrews, Geoffrey; Shi, Wentao; Liu, Yaling

2016-02-01

With the increasing amount of research work in surface studies, a more effective method of producing patterned microstructures is highly desired due to the geometric limitations and complex fabricating process of current techniques. This paper presents an efficient and cost-effective method to generate customizable micro-wavy pattern using direct image lithography. This method utilizes a grayscale Gaussian distribution effect to model inaccuracies inherent in the polymerization process, which are normally regarded as trivial matters or errors. The measured surface profiles and the mathematical prediction show a good agreement, demonstrating the ability of this method to generate wavy patterns with precisely controlled features. An accurate pattern can be generated with customizable parameters (wavelength, amplitude, wave shape, pattern profile, and overall dimension). This mask-free photolithography approach provides a rapid fabrication method that is capable of generating complex and non-uniform 3D wavy patterns with the wavelength ranging from 12 μm to 2100 μm and an amplitude-to-wavelength ratio as large as 300%. Microfluidic devices with pure wavy and wavy-herringbone patterns suitable for capture of circulating tumor cells are made as a demonstrative application. A completely customized microfluidic device with wavy patterns can be created within a few hours without access to clean room or commercial photolithography equipment.

Dietary Patterns in Relation to General and Central Obesity among Adults in Southwest China.

Science.gov (United States)

Zhang, Qiang; Chen, Xinguang; Liu, Zhitao; Varma, Deepthi S; Wan, Rong; Wan, Qingqing; Zhao, Shiwen

2016-11-03

Dietary patterns represent a broader picture of food consumption, and are better correlated with a variety of health outcomes. However, few studies have been conducted to explore the associations between dietary patterns and obesity in Southwest China. Data from the 2010-2012 National Nutrition Survey in the province of Yunnan, Southwest China, were analyzed ( n = 1604, aged 18-80 years). Dietary data were collected using the 24 h dietary recall over three consecutive days. Height, weight, and waist circumference were measured following standard methods. Exploratory factor analysis was used to identify dietary patterns. Logistic regression was used to explore the association between dietary patterns and obesity. Three distinct dietary patterns were identified, which were labeled as traditional, modern, and tuber according to their key components. With potential confounders adjusted, adults in the highest quartile of the modern pattern were at higher risk of general and central obesity (odds ratio (OR) 1.95, 95% confidence interval (CI) 1.15-3.48; OR 2.01, 95% CI 1.37-2.93). In contrast, adults in the highest quartile of the tuber pattern were at lower risk of general and central obesity (OR 0.34, 95% CI 0.15-0.61; OR 0.64, 95% CI 0.43-0.95) but at higher risk of underweight (OR 2.57, 95% CI 1.20-6.45). No significant association was found between the traditional pattern and obesity. Moreover, dietary pattern differences occurred due to the differences in socio-demographic characteristics. In conclusion, the modern dietary pattern was positively, and the tuber pattern negatively, associated with general and central obesity among adults in Southwest China.

Automatic Generation of English-Japanese Translation Pattern Utilizing Genetic Programming Technique

Science.gov (United States)

Matsumura, Koki; Tamekuni, Yuji; Kimura, Shuhei

There are a lot of constructional differences in an English-Japanese phrase template, and that often makes the act of translation difficult. Moreover, there exist various and tremendous phrase templates and sentence to be refered to. It is not easy to prepare the corpus that covers the all. Therefore, it is very significant to generate the translation pattern of the sentence pattern automatically from a viewpoint of the translation success rate and the capacity of the pattern dictionary. Then, for the purpose of realizing the automatic generation of the translation pattern, this paper proposed the new method for the generation of the translation pattern by using the genetic programming technique (GP). The technique tries to generate the translation pattern of various sentences which are not registered in the phrase template dictionary automatically by giving the genetic operation to the parsing tree of a basic pattern. The tree consists of the pair of the English-Japanese sentence generated as the first stage population. The analysis tree data base with 50,100,150,200 pairs was prepared as the first stage population. And this system was applied and executed for an English input of 1,555 sentences. As a result, the analysis tree increases from 200 to 517, and the accuracy rate of the translation pattern has improved from 42.57% to 70.10%. And, 86.71% of the generated translations was successfully done, whose meanings are enough acceptable and understandable. It seemed that this proposal technique became a clue to raise the translation success rate, and to find the possibility of the reduction of the analysis tree data base.

Centralized power generation: what share for gas?

International Nuclear Information System (INIS)

Honore, A.; Pharabod, E.; Lecointe, O.; Poyer, L.

2007-01-01

Up to a recent past, most energy scenarios were foreseeing a fast growth of natural gas consumption thanks to an assumed strong penetration of gas-fueled power plants. The share of natural gas in the centralized power generation has been the subject of a meeting of the French gas association (AFG) which aimed at answering the following questions: today's position of gas power generation in Europe in the present day context of gas prices (level, volatility), the share of natural gas in the French power mix in the coming years, the strategies of development of gas power plants by historical operators and newcomers, the gas arbitration between its sale to end-users and its use for power generation, and the integration of the CO 2 risk. (J.S.)

Neural Sequence Generation Using Spatiotemporal Patterns of Inhibition.

Directory of Open Access Journals (Sweden)

Jonathan Cannon

2015-11-01

Full Text Available Stereotyped sequences of neural activity are thought to underlie reproducible behaviors and cognitive processes ranging from memory recall to arm movement. One of the most prominent theoretical models of neural sequence generation is the synfire chain, in which pulses of synchronized spiking activity propagate robustly along a chain of cells connected by highly redundant feedforward excitation. But recent experimental observations in the avian song production pathway during song generation have shown excitatory activity interacting strongly with the firing patterns of inhibitory neurons, suggesting a process of sequence generation more complex than feedforward excitation. Here we propose a model of sequence generation inspired by these observations in which a pulse travels along a spatially recurrent excitatory chain, passing repeatedly through zones of local feedback inhibition. In this model, synchrony and robust timing are maintained not through redundant excitatory connections, but rather through the interaction between the pulse and the spatiotemporal pattern of inhibition that it creates as it circulates the network. These results suggest that spatially and temporally structured inhibition may play a key role in sequence generation.

Neural Sequence Generation Using Spatiotemporal Patterns of Inhibition.

Science.gov (United States)

Cannon, Jonathan; Kopell, Nancy; Gardner, Timothy; Markowitz, Jeffrey

2015-11-01

Stereotyped sequences of neural activity are thought to underlie reproducible behaviors and cognitive processes ranging from memory recall to arm movement. One of the most prominent theoretical models of neural sequence generation is the synfire chain, in which pulses of synchronized spiking activity propagate robustly along a chain of cells connected by highly redundant feedforward excitation. But recent experimental observations in the avian song production pathway during song generation have shown excitatory activity interacting strongly with the firing patterns of inhibitory neurons, suggesting a process of sequence generation more complex than feedforward excitation. Here we propose a model of sequence generation inspired by these observations in which a pulse travels along a spatially recurrent excitatory chain, passing repeatedly through zones of local feedback inhibition. In this model, synchrony and robust timing are maintained not through redundant excitatory connections, but rather through the interaction between the pulse and the spatiotemporal pattern of inhibition that it creates as it circulates the network. These results suggest that spatially and temporally structured inhibition may play a key role in sequence generation.

Feedback Signal from Motoneurons Influences a Rhythmic Pattern Generator.

Science.gov (United States)

Rotstein, Horacio G; Schneider, Elisa; Szczupak, Lidia

2017-09-20

Motoneurons are not mere output units of neuronal circuits that control motor behavior but participate in pattern generation. Research on the circuit that controls the crawling motor behavior in leeches indicated that motoneurons participate as modulators of this rhythmic motor pattern. Crawling results from successive bouts of elongation and contraction of the whole leech body. In the isolated segmental ganglia, dopamine can induce a rhythmic antiphasic activity of the motoneurons that control contraction (DE-3 motoneurons) and elongation (CV motoneurons). The study was performed in isolated ganglia where manipulation of the activity of specific motoneurons was performed in the course of fictive crawling ( crawling ). In this study, the membrane potential of CV was manipulated while crawling was monitored through the rhythmic activity of DE-3. Matching behavioral observations that show that elongation dominates the rhythmic pattern, the electrophysiological activity of CV motoneurons dominates the cycle. Brief excitation of CV motoneurons during crawling episodes resets the rhythmic activity of DE-3, indicating that CV feeds back to the rhythmic pattern generator. CV hyperpolarization accelerated the rhythm to an extent that depended on the magnitude of the cycle period, suggesting that CV exerted a positive feedback on the unit(s) of the pattern generator that controls the elongation phase. A simple computational model was implemented to test the consequences of such feedback. The simulations indicate that the duty cycle of CV depended on the strength of the positive feedback between CV and the pattern generator circuit. SIGNIFICANCE STATEMENT Rhythmic movements of animals are controlled by neuronal networks that have been conceived as hierarchical structures. At the basis of this hierarchy, we find the motoneurons, few neurons at the top control global aspects of the behavior (e.g., onset, duration); and within these two ends, specific neuronal circuits control

Dietary patterns are associated with general and central obesity in elderly living in a Brazilian city

Directory of Open Access Journals (Sweden)

Priscila Lucelia Moreira

2014-10-01

Full Text Available Objective: dietary pattern evaluation is often used in order to determine wheter a diet is healthy, as well as to predict the onset of diseases. This study aimed to identify dietary patterns, and to examine their associations with general (body mass index and central (waist circumference and waist-to-hip ratio obesity in community-living elderly in a Brazilian city. Methods: this cross-sectional study included 126 elderly subjects aged 60 or older (57.1% females and mean age 74.2 ± 6.46 years. Anthropometric variables, weight, height, waist (WC and hip (HC circumferences, were measured. Body mass index (BMI and waist-to-hip ratio (WHR were calculated. Answers to a Food Frequency Questionnaire were interpreted by Principal Component Analysis in order to identify dietary patterns. Results: five dietary patterns were identified and named as prudent (fruit, vegetables and meat, sweets and fats (pastries, sugary foods, fatty foods, whole milk, typical Brazilian (fried eggs, cooked beans, beef, candy, string beans, fried cassava, Mediterranean (fruit, vegetables, olive oil and nuts and traditional meal (rice and beans. Moderate and high adherences to the Mediterranean pattern were protective factors to general and central obesity (WHR. High adherence to prudent was also protective to central obesity (WC. Conclusion: adherences to the dietary patterns prudent and Mediterranean were protective factors to general and central obesity in elderly.

Dietary patterns in India and their association with obesity and central obesity.

Science.gov (United States)

Satija, Ambika; Hu, Frank B; Bowen, Liza; Bharathi, Ankalmadugu V; Vaz, Mario; Prabhakaran, Dorairaj; Reddy, K Srinath; Ben-Shlomo, Yoav; Davey Smith, George; Kinra, Sanjay; Ebrahim, Shah

2015-11-01

Obesity is a growing problem in India, the dietary determinants of which have been studied using an 'individual food/nutrient' approach. Examining dietary patterns may provide more coherent findings, but few studies in developing countries have adopted this approach. The present study aimed to identify dietary patterns in an Indian population and assess their relationship with anthropometric risk factors. FFQ data from the cross-sectional sib-pair Indian Migration Study (IMS; n 7067) were used to identify dietary patterns using principal component analysis. Mixed-effects logistic regression was used to examine associations with obesity and central obesity. The IMS was conducted at four factory locations across India: Lucknow, Nagpur, Hyderabad and Bangalore. The participants were rural-to-urban migrant and urban non-migrant factory workers, their rural and urban resident siblings, and their co-resident spouses. Three dietary patterns were identified: 'cereals-savoury foods' (cooked grains, rice/rice-based dishes, snacks, condiments, soups, nuts), 'fruit-veg-sweets-snacks' (Western cereals, vegetables, fruit, fruit juices, cooked milk products, snacks, sugars, sweets) and 'animal-food' (red meat, poultry, fish/seafood, eggs). In adjusted analysis, positive graded associations were found between the 'animal-food' pattern and both anthropometric risk factors. Moderate intake of the 'cereals-savoury foods' pattern was associated with reduced odds of obesity and central obesity. Distinct dietary patterns were identified in a large Indian sample, which were different from those identified in previous literature. A clear 'plant food-based/animal food-based pattern' dichotomy emerged, with the latter being associated with higher odds of anthropometric risk factors. Longitudinal studies are needed to further clarify this relationship in India.

Effects of traffic generation patterns on the robustness of complex networks

Science.gov (United States)

Wu, Jiajing; Zeng, Junwen; Chen, Zhenhao; Tse, Chi K.; Chen, Bokui

2018-02-01

Cascading failures in communication networks with heterogeneous node functions are studied in this paper. In such networks, the traffic dynamics are highly dependent on the traffic generation patterns which are in turn determined by the locations of the hosts. The data-packet traffic model is applied to Barabási-Albert scale-free networks to study the cascading failures in such networks and to explore the effects of traffic generation patterns on network robustness. It is found that placing the hosts at high-degree nodes in a network can make the network more robust against both intentional attacks and random failures. It is also shown that the traffic generation pattern plays an important role in network design.

Coastal ocean transport patterns in the central Southern California Bight

Science.gov (United States)

Noble, M.A.; Rosenberger, K.J.; Hamilton, P.; Xu, J. P.

2009-01-01

In the past decade, several large programs that monitor currents and transport patterns for periods from a few months to a few years were conducted by a consortium of university, federal, state, and municipal agencies in the central Southern California Bight, a heavily urbanized section of the coastal ocean off the west coast of the United States encompassing Santa Monica Bay, San Pedro Bay, and the Palos Verdes shelf. These programs were designed in part to determine how alongshelf and cross-shelf currents move sediments, pollutants, and suspended material through the region. Analysis of the data sets showed that the current patterns in this portion of the Bight have distinct changes in frequency and amplitude with location, in part because the topography of the shelf and upper slope varies rapidly over small spatial scales. However, because the mean, subtidal, and tidal-current patterns in any particular location were reasonably stable with time, one could determine a regional pattern for these current fields in the central Southern California Bight even though measurements at the various locations were obtained at different times. In particular, because the mean near-surface flows over the San Pedro and Palos Verdes shelves are divergent, near-surface waters from the upper slope tend to carry suspended material onto the shelf in the northwestern portion of San Pedro Bay. Water and suspended material are also carried off the shelf by the mean and subtidal flow fields in places where the orientation of the shelf break changes abruptly. The barotropic tidal currents in the central Southern California Bight flow primarily alongshore, but they have pronounced amplitude variations over relatively small changes in alongshelf location that are not totally predicted by numerical tidal models. Nonlinear internal tides and internal bores at tidal frequencies are oriented more across the shelf. They do not have a uniform transport direction, since they move fine sediment

The New England travel market: generational travel patterns, 1979 to 1996

Science.gov (United States)

Rod Warnick

2002-01-01

Generations of travelers who select New England as a primary destination are examined over time from the years of 1979 through 1996 and the analysis serves to update an earlier review of generational travel patterns of the region (Warnick, 1994). Changes in travel patterns are noted by overall adjusted annual change rates by demographic and geographic regions of...

Dual CARS and SHG image acquisition scheme that combines single central fiber and multimode fiber bundle to collect and differentiate backward and forward generated photons

Science.gov (United States)

Weng, Sheng; Chen, Xu; Xu, Xiaoyun; Wong, Kelvin K.; Wong, Stephen T. C.

2016-01-01

In coherent anti-Stokes Raman scattering (CARS) and second harmonic generation (SHG) imaging, backward and forward generated photons exhibit different image patterns and thus capture salient intrinsic information of tissues from different perspectives. However, they are often mixed in collection using traditional image acquisition methods and thus are hard to interpret. We developed a multimodal scheme using a single central fiber and multimode fiber bundle to simultaneously collect and differentiate images formed by these two types of photons and evaluated the scheme in an endomicroscopy prototype. The ratio of these photons collected was calculated for the characterization of tissue regions with strong or weak epi-photon generation while different image patterns of these photons at different tissue depths were revealed. This scheme provides a new approach to extract and integrate information captured by backward and forward generated photons in dual CARS/SHG imaging synergistically for biomedical applications. PMID:27375938

Pattern-set generation algorithm for the one-dimensional multiple stock sizes cutting stock problem

Science.gov (United States)

Cui, Yaodong; Cui, Yi-Ping; Zhao, Zhigang

2015-09-01

A pattern-set generation algorithm (PSG) for the one-dimensional multiple stock sizes cutting stock problem (1DMSSCSP) is presented. The solution process contains two stages. In the first stage, the PSG solves the residual problems repeatedly to generate the patterns in the pattern set, where each residual problem is solved by the column-generation approach, and each pattern is generated by solving a single large object placement problem. In the second stage, the integer linear programming model of the 1DMSSCSP is solved using a commercial solver, where only the patterns in the pattern set are considered. The computational results of benchmark instances indicate that the PSG outperforms existing heuristic algorithms and rivals the exact algorithm in solution quality.

Enhancing SAT-Based Test Pattern Generation

Institute of Scientific and Technical Information of China (English)

LIU Xin; XIONG You-lun

2005-01-01

This paper presents modeling tools based on Boolean satisfiability (SAT) to solve problems of test generation for combinational circuits. It exploits an added layer to maintain circuit-related information and value justification relations to a generic SAT algorithm. It dovetails binary decision graphs (BDD) and SAT techniques to improve the efficiency of automatic test pattern generation (ATPG). More specifically, it first exploits inexpensive reconvergent fanout analysis of circuit to gather information on the local signal correlation by using BDD learning, then uses the above learned information to restrict and focus the overall search space of SAT-based ATPG. Its learning technique is effective and lightweight. The experimental results demonstrate the effectiveness of the approach.

Dynamic array generation and pattern formation for optical tweezers

DEFF Research Database (Denmark)

Mogensen, P.C.; Glückstad, J.

2000-01-01

The generalised phase contrast approach is used for the generation of optical arrays of arbitrary beam shape, suitable for applications in optical tweezers for the manipulation of biological specimens. This approach offers numerous advantages over current techniques involving the use of computer......-generated holograms or diffractive optical elements. We demonstrate a low-loss system for generating intensity patterns suitable for the trapping and manipulation of small particles or specimens....

Pattern of Head and neck malignancies in Central Sudan-(study of ...

African Journals Online (AJOL)

Objective: The objective of this work is to study the patterns of head and neck malignancies (HNM) in central Sudan and to compare it with international published series. Methods: This is a retrospective study conducted at the Institute of Nuclear Medicine, Molecular Biology and Oncology (INMO)-University of Gezira; ...

Quantum properties of transverse pattern formation in second-harmonic generation

DEFF Research Database (Denmark)

Bache, Morten; Scotto, P.; Zambrini, R.

2002-01-01

these equations through extensive numerical simulations and analytically in the linearized limit. Our study, made below and above the threshold of pattern formation, is guided by a microscopic scheme of photon interaction underlying pattern formation in second-harmonic generation. Close to the threshold...

Sizing and Optimization for Hybrid Central in South Algeria Based on Three Different Generators

Directory of Open Access Journals (Sweden)

Chouaib Ammari

2017-11-01

Full Text Available In this paper, we will size an optimum hybrid central content three different generators, two on renewable energy (solar photovoltaic and wind power and two nonrenewable (diesel generator and storage system because the new central generator has started to consider the green power technology in order for best future to the world, this central will use all the green power resource available and distributes energy to a small isolated village in southwest of Algeria named “Timiaouine”. The consumption of this village estimated with detailed in two season; season low consumption (winter and high consumption (summer, the hybrid central will be optimized by program Hybrid Optimization Model for Electric Renewable (HOMER PRO, this program will simulate in two configuration, the first with storage system, the second without storage system and in the end the program HOMER PRO will choose the best configuration which is the mixture of both economic and ecologic configurations, this central warrants the energetic continuity of village. Article History: Received May 18th 2017; Received in revised form July 17th 2017; Accepted Sept 3rd 2017; Available online How to Cite This Article: Ammari, C., Hamouda,M., and Makhloufi,S. (2017 Sizing and Optimization for Hybrid Central in South Algeria Based on Three Different Generators. International Journal of Renewable Energy Development, 6(3, 263-272. http://doi.org/10.14710/ijred.6.3.263-272

THE SIGNIFICANCE OF PATTERN ERG IN CENTRAL VEIN OCCLUSION

Directory of Open Access Journals (Sweden)

Saša Novak

2004-12-01

Full Text Available Pattern electroretinogram (PERG findings were analysed in 30 patients with central retinal vein occlusion. Latency and amplitude values of PERG waves were compared with the results obtained in 30 healthy individuals after sample randomisation. In 15 cases with „hemorrhagic type” occlusion of the central retinal vein significantly reduced N1-P1 wave amplitude was noted (0,369 mV, related to „exudative“ disease type (0,557 mV, as well as to the control group of examines (0,782 mV. PERG was described as the sensitive method and important indicator in damage assessment, ie. ischemia in the ganglional cell layer in central retinal vein occlusion. Ischemia increases anoxia, which influences not only the axons but also the enzymatic and transport processes within the cell bodies, dendrites, axons and axonal terminals. Slowing down of the fast phase of axoplasmatic transport in the axons in ischemic damage blocked transmission impulses which could be evident through different degrees of PERG wave amplitude reduction. With this method the patients can be selected in whom due to severe retinal ischemia there is the risk of neovascular glaucomma and maculopathy, which is the absolute indication for panlaser-photocoagulation.

Generational Politics: Narratives of Power in Central Asia's Visual Culture

OpenAIRE

Khudonazar, Anaita

2011-01-01

This dissertation focuses on the visual representation of generational politics as it changed during Imperial, Soviet and Post Soviet periods. It argues that the most important shift in visual representation of power relations between generations in Central Asia took place in the late 1920s when a group of cultural producers, which this dissertation introduces as Transsoveticus, entered the Soviet art and film industries. This dissertation demonstrates ways in which these artists and filmmak...

The New England travel market: changes in generational travel patterns

Science.gov (United States)

Rodney B. Warnick

1995-01-01

The purpose of this study was to examine and explore the New England domestic travel market trends, from 1979 through 1991 within the context of generations. The existing travel markets, who travel to New England, are changing by age cohorts and specifically within different generations. The New England changes in generational travel patterns do not reflect national...

Patterning techniques for next generation IC's

Science.gov (United States)

Balasinski, A.

2007-12-01

Reduction of linear critical dimensions (CDs) beyond 45 nm would require significant increase of the complexity of pattern definition process. In this work, we discuss the key successor methodology to the current optical lithography, the Double Patterning Technique (DPT). We compare the complexity of CAD solutions, fab equipment, and wafer processing with its competitors, such as the nanoimprint (NIL) and the extreme UV (EUV) techniques. We also look ahead to the market availability for the product families enabled using the novel patterning solutions. DPT is often recognized as the most viable next generation lithography as it utilizes the existing equipment and processes and is considered a stop-gap solution before the advanced NIL or EUV equipment is developed. Using design for manufacturability (DfM) rules, DPT can drive the k1 factor down to 0.13. However, it faces a variety of challenges, from new mask overlay strategies, to layout pattern split, novel OPC, increased CD tolerances, new etch techniques, as well as long processing time, all of which compromise its return on investment (RoI). In contrast, it can be claimed e.g., that the RoI is the highest for the NIL but this technology bears significant risk. For all novel patterning techniques, the key questions remain: when and how should they be introduced, what is their long-term potential, when should they be replaced, and by what successor technology. We summarize the unpublished results of several panel discussions on DPT at the recent SPIE/BACUS conferences.

Implementing gait pattern control and transition for legged locomotion

International Nuclear Information System (INIS)

Yang, Zhijun; Karamanoglu, Mehmet; Rocha, Marlon V; França, Felipe M G; Lima, Priscila M V

2014-01-01

In this work, a generalised central pattern generator (CPG) model is formulated to generate a full range of gait patterns for a hexapod insect. To this end, a recurrent neuronal network module, as the building block for rhythmic patterns, is proposed to extend the concept of oscillatory building blocks (OBB) for constructing a CPG model. The model is able to make transitions between different gait patterns by simply adjusting one model parameter. Simulation results are further presented to show the effectiveness and performance of the CPG network

On-Shore Central Hydraulic Power Generation for Wind and Tidal Energy

Science.gov (United States)

Jones, Jack A.; Bruce, Allan; Lim, Steven; Murray, Luke; Armstrong, Richard; Kimbrall, Richard; Cook-Chenault, Kimberly; DeGennaro, Sean

2012-01-01

Tidal energy, offshore wind energy, and onshore wind energy can be converted to electricity at a central ground location by means of converting their respective energies into high-pressure hydraulic flows that are transmitted to a system of generators by high-pressure pipelines. The high-pressure flows are then efficiently converted to electricity by a central power plant, and the low-pressure outlet flow is returned. The Department of Energy (DOE) is presently supporting a project led by Sunlight Photonics to demonstrate a 15 kW tidal hydraulic power generation system in the laboratory and possibly later submerged in the ocean. All gears and submerged electronics are completely eliminated. A second portion of this DOE project involves sizing and costing a 15 MW tidal energy system for a commercial tidal energy plant. For this task, Atlantis Resources Corporation s 18-m diameter demonstrated tidal blades are rated to operate in a nominal 2.6 m/sec tidal flow to produce approximately one MW per set of tidal blades. Fifteen units would be submerged in a deep tidal area, such as in Maine s Western Passage. All would be connected to a high-pressure (20 MPa, 2900 psi) line that is 35 cm ID. The high-pressure HEPG fluid flow is transported 500-m to on-shore hydraulic generators. HEPG is an environmentally-friendly, biodegradable, watermiscible fluid. Hydraulic adaptations to ORPC s cross-flow turbines are also discussed. For 15 MW of wind energy that is onshore or offshore, a gearless, high efficiency, radial piston pump can replace each set of top-mounted gear-generators. The fluid is then pumped to a central, easily serviceable generator location. Total hydraulic/electrical efficiency is 0.81 at full rated wind or tidal velocities and increases to 0.86 at 1/3 rated velocities.

Diversity patterns and composition of native and exotic floras in central Chile

Science.gov (United States)

Figueroa, Javier A.; Teillier, Sebastián; Castro, Sergio A.

2011-03-01

Floristic changes in the Mediterranean region of central Chile brought about by human impact appear to be shared with other climatic regions, although there is a notable absence of empirical studies and available quantitative evidence for the central Chile region. This study examines the cover, richness and composition of native and exotic plant species in a representative area of central Chile. Through floristic characterization of 33 sites sampled using 40 × 40 m plots distributed along transect on which the two farthest sites were separated by 50 km, the floristic richness and cover patterns, as well as the general land use characteristics were evaluated (native matorral, espinal, abandoned farming field, forest plantations, periurban sites, road sites, river bank, and burnt site). We recorded 327 species of plants; 213 species were native and 114 were exotic. The average number of species was heterogeneous in all sites, showing a greater relative native frequency in those sites with a lower level of anthropic intervention. Except for the matorral, the cover of exotic species was greater than that of native species. No relation was found between richness and cover in relation to the different types of land use. The relationship between cover of native and exotic was negative, although for richness did not show relationship. Results show that the exotic species are limited by resources, although they have not completely displaced the native species. The native and exotic floras respond to different spatial distribution patterns, so their presence makes it possible to establish two facts rarely quantified in central Chile: first, that the exotic flora replaces (but does not necessarily displace) the native flora, and second, that at the same time, because of its greater geographic ubiquity and the abundance levels that it achieves, it contributes to the taxonomic and physiognomic homogenization of central Chile.

Electric vehicle charge patterns and the electricity generation mix and competitiveness of next generation vehicles

International Nuclear Information System (INIS)

Masuta, Taisuke; Murata, Akinobu; Endo, Eiichi

2014-01-01

Highlights: • The energy system of whole of Japan is analyzed in this study. • An advanced model based on MARKAL is used for the energy system analysis. • The impact of charge patterns of EVs on electricity generation mix is evaluated. • Technology competitiveness of the next generation vehicles is also evaluated. - Abstract: The nuclear accident of 2011 brought about a reconsideration of the future electricity generation mix of power systems in Japan. A debate on whether to phase out nuclear power plants and replace them with renewable energy sources is taking place. Demand-side management becomes increasingly important in future Japanese power systems with a large-scale integration of renewable energy sources. This paper considers the charge control of electric vehicles (EVs) through demand-side management. There have been many studies of the control or operation methods of EVs known as vehicle-to-grid (V2G), and it is important to evaluate both their short-term and long-term operation. In this study, we employ energy system to evaluate the impact of the charge patterns of EVs on both the electricity generation mix and the technology competitiveness of the next generation vehicles. An advanced energy system model based on Market Allocation (MARKAL) is used to consider power system control in detail

A third generation of performance contracting in danish central government?

DEFF Research Database (Denmark)

Kristiansen, Mads Bøge

2017-01-01

This paper compares the content of performance contracts in Danish central government over time in order to identify whether – and if so, how – it develops. The analysis is conducted as a two-step, mixed methods study. First, a quantitative study was carried out based on a study of all performance...... contracts in Danish central government in 2002, 2006, 2009, 2012 and 2014. For each year, all performance contracts have been coded according to the number and type of targets included in them. A range of qualitative interviews was then carried out, and Ministry of Finance recommendations were consulted...... of outcomes has increased, activity-oriented targets have decreased, and targets for internal management decreased in the mid-2000s before again increasing more recently. On this basis, performance contracting in Danish central government is argued to have entered a third generation....

Reproduction Patterns of Scleractinian Corals in the Central Red Sea

KAUST Repository

Bouwmeester, Jessica

2013-12-01

Early work on the reproductive seasonality of corals in the Red Sea suggested that corals exhibit temporal reproductive isolation, unlike on the Great Barrier Reef where many species spawn in synchrony. More recent work has however shown high synchrony in the maturity of gametes in Acropora species, suggesting multi-specific spawning is likely to occur in the Red Sea. In this thesis I investigate the patterns of coral reproduction in the central Red Sea. The spawning season in the central Red Sea lasts four months, from April to July and spawning occurs on nights around the full moon. During this period Acropora species show a peak of spawning in April, with some species spawning again in May. The level of synchrony, quantified with a spawning synchrony index, is comparable to other locations where multi-specific spawning has been reported. Observations over two consecutive years show that the synchrony of spawning was lower in spring 2012 than in spring 2011, and thus that spawning patterns are variable from one year to the other. Coral settlement patterns on artificial substrata confirmed a main spawning season in the spring but also supported reproductive data suggesting that some Porites spawn in October-November. Settlement was studied over 2.5 years on a reef, which had suffered recently from high mortality after a local bleaching event. Settlement appeared low but post-bleaching studies from other locations indicated similar abundances and showed that recruits generally did not increase until 5 years after the bleaching event. Abundance of juvenile corals however started to increase significantly three years after the bleaching. Successful recruitment, although low suggests that the coral assemblage on the affected reef will most likely recover as long as it is not affected by another disturbance.

Motor Patterns in Walking.

Science.gov (United States)

Lacquaniti, F.; Grasso, R.; Zago, M.

1999-08-01

Despite the fact that locomotion may differ widely in mammals, common principles of kinematic control are at work. These reflect common mechanical and neural constraints. The former are related to the need to maintain balance and to limit energy expenditure. The latter are related to the organization of the central pattern-generating networks.

A low cost high resolution pattern generator for electron-beam lithography

International Nuclear Information System (INIS)

Pennelli, G.; D'Angelo, F.; Piotto, M.; Barillaro, G.; Pellegrini, B.

2003-01-01

A simple, very low cost pattern generator for electron-beam lithography is presented. When it is applied to a scanning electron microscope, the system allows a high precision positioning of the beam for lithography of very small structures. Patterns are generated by a suitable software implemented on a personal computer, by using very simple functions, allowing an easy development of new writing strategies for a great adaptability to different user necessities. Hardware solutions, as optocouplers and battery supply, have been implemented for reduction of noise and disturbs on the voltages controlling the positioning of the beam

Generation of mask patterns for diffractive optical elements using MathematicaTM

International Nuclear Information System (INIS)

OShea, D.C.

1996-01-01

The generation of binary and grayscale masks used in the fabrication of diffractive optical elements is usually performed using a proprietary piece of software or a computer-aided drafting package. Once the pattern is computed or designed, it must be output to a plotting or imaging system that will produce a reticle plate. This article describes a number of short Mathematica modules that can be used to generate binary and grayscale patterns in a PostScript-compatible format. Approaches to ensure that the patterns are directly related to the function of the element and the design wavelength are discussed. A procedure to preserve the scale of the graphic output when it is transferred to another application is given. Examples of surfaces for a 100 mm effective focal length lens and an Alvarez surface are given. copyright 1996 American Institute of Physics

Automating the generation of lexical patterns for processing free text in clinical documents.

Science.gov (United States)

Meng, Frank; Morioka, Craig

2015-09-01

Many tasks in natural language processing utilize lexical pattern-matching techniques, including information extraction (IE), negation identification, and syntactic parsing. However, it is generally difficult to derive patterns that achieve acceptable levels of recall while also remaining highly precise. We present a multiple sequence alignment (MSA)-based technique that automatically generates patterns, thereby leveraging language usage to determine the context of words that influence a given target. MSAs capture the commonalities among word sequences and are able to reveal areas of linguistic stability and variation. In this way, MSAs provide a systemic approach to generating lexical patterns that are generalizable, which will both increase recall levels and maintain high levels of precision. The MSA-generated patterns exhibited consistent F1-, F.5-, and F2- scores compared to two baseline techniques for IE across four different tasks. Both baseline techniques performed well for some tasks and less well for others, but MSA was found to consistently perform at a high level for all four tasks. The performance of MSA on the four extraction tasks indicates the method's versatility. The results show that the MSA-based patterns are able to handle the extraction of individual data elements as well as relations between two concepts without the need for large amounts of manual intervention. We presented an MSA-based framework for generating lexical patterns that showed consistently high levels of both performance and recall over four different extraction tasks when compared to baseline methods. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fluid power network for centralized electricity generation in offshore wind farms

NARCIS (Netherlands)

Jarquin-Laguna, A.

2014-01-01

An innovative and completely different wind-energy conversion system is studied where a centralized electricity generation within a wind farm is proposed by means of a hydraulic network. This paper presents the dynamic interaction of two turbines when they are coupled to the same hydraulic network.

The activation pattern of macrophages in giant cell (temporal) arteritis and primary angiitis of the central nervous system.

Science.gov (United States)

Mihm, Bernhard; Bergmann, Markus; Brück, Wolfgang; Probst-Cousin, Stefan

2014-06-01

To determine if the pattern of macrophage activation reflects differences in the pathogenesis and clinical presentation of giant cell arteritis and primary angiitis of the central nervous system, specimens of 10 patients with giant cell arteritis and five with primary angiitis of the central nervous system were immunohistochemically studied and the expression of the macrophage activation markers 27E10, MRP14, MRP8 and 25F9 was determined in the vasculitic infiltrates. Thus, a partly different expression pattern of macrophage activation markers in giant cell arteritis and primary angiitis of the central nervous system was observed. The group comparison revealed that giant cell arteritis cases had significantly higher numbers of acute activated MRP14-positive macrophages, whereas primary angiitis of the central nervous system is characterized by a tendency toward more MRP8-positive intermediate/late activated macrophages. Furthermore, in giant cell arteritis comparably fewer CD8-positive lymphocytes were observed. These observations suggest, that despite their histopathological similarities, giant cell arteritis and primary angiitis of the central nervous system appear to represent either distinct entities within the spectrum of granulomatous vasculitides or different stages of similar disease processes. Their discrete clinical presentation is reflected by different activation patterns of macrophages, which may characterize giant cell arteritis as a more acute process and primary angiitis of the central nervous system as a more advanced inflammatory process. © 2013 Japanese Society of Neuropathology.

Climate change and farmers’ cropping patterns in Cemoro watershed area, Central Java, Indonesia

Science.gov (United States)

Sugihardjo; Sutrisno, J.; Setyono, P.; Suntoro

2018-03-01

Cropping pattern applied by farmers is usually based on the availability of water. Farmers cultivate rice when water is available. If it is unavailable, farmers will choose to plant crops that need less water. Climate change greatly affects to farmers in determining the cropping pattern as it alters the rainfall pattern and distribution in the region. This condition requires farmers to adjust the cropping pattern so that they can do the farming successfully. This study aims to examine the application of cropping patterns applied by the farmers in the Cemoro Watershed, Central Java, Indonesia. Descriptive analysis approach is employed in this research. The results showed that farmers’ cropping pattern is not based on the availability of water. However, it adopts a habit that has been practiced since long time ago or just adopt others farmer's habit. The cropping pattern applied by irrigated paddy farmers in Cemoro watershed area consists of two types: rice-rice-rice and rice-rice-secondary crops. Among those two types, most farmers apply the rice-rice-rice pattern. Meanwhile, there are three cropping patterns applied in the rain-land, namely rice-rice-rice, rice-rice-secondary crop, and rice-rice-fallow. The majority of farmers apply the second pattern (rice-rice-secondary crops). It was also found that farmers’ cropping pattern was not in accordance with the recommendation of the local government.

Electric generator overhaul of the Ing. Carlos Ramirez Ulloa hydroelectric. Central project conclusions; Rehabilitacion de los generadores de la central hidroelectrica Ing. Carlos Ramirez Ulloa. Conclusiones del proyecto

Energy Technology Data Exchange (ETDEWEB)

Campuzano Martinez, Ignacio Roberto; Gonzalez Vazquez, Alejandro Esteban; Robles Pimentel, Edgar Guillermo; Esparza Saucedo, Marcos; Garcia Martinez, Javier; Sanchez Flores, Ernesto; Martinez Romero, Jose Luis [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1999-12-31

The Hydroelectric Ing. Carlos Ramirez Ulloa Power Central has three 200 MW electric generators. The Central initiated its commercial operation in 1985. The electric generators had design problems that were properly corrected in an overhaul program that was initiated in 1996, with Unit 2 electric generator and completed in 1998 with Unit 1 electric generator. This paper presents the relevant aspects of the experience accumulated in the project. [Espanol] La central hidroelectrica Ing. Carlos Ramirez Ulloa cuenta con tres generadores de 200 MW cada uno. La central inicio su operacion comercial en 1985. Los generadores tenian problemas de diseno que fueron debidamente corregidos en un programa de rehabilitacion que inicio en 1996, con el generador de la unidad 2, y culmino en 1998 con el generador de la unidad 1. En este articulo se presentan los aspectos relevantes de la experiencia acumulada en el proyecto.

Electric generator overhaul of the Ing. Carlos Ramirez Ulloa hydroelectric. Central project conclusions; Rehabilitacion de los generadores de la central hidroelectrica Ing. Carlos Ramirez Ulloa. Conclusiones del proyecto

Energy Technology Data Exchange (ETDEWEB)

Campuzano Martinez, Ignacio Roberto; Gonzalez Vazquez, Alejandro Esteban; Robles Pimentel, Edgar Guillermo; Esparza Saucedo, Marcos; Garcia Martinez, Javier; Sanchez Flores, Ernesto; Martinez Romero, Jose Luis [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1998-12-31

The Hydroelectric Ing. Carlos Ramirez Ulloa Power Central has three 200 MW electric generators. The Central initiated its commercial operation in 1985. The electric generators had design problems that were properly corrected in an overhaul program that was initiated in 1996, with Unit 2 electric generator and completed in 1998 with Unit 1 electric generator. This paper presents the relevant aspects of the experience accumulated in the project. [Espanol] La central hidroelectrica Ing. Carlos Ramirez Ulloa cuenta con tres generadores de 200 MW cada uno. La central inicio su operacion comercial en 1985. Los generadores tenian problemas de diseno que fueron debidamente corregidos en un programa de rehabilitacion que inicio en 1996, con el generador de la unidad 2, y culmino en 1998 con el generador de la unidad 1. En este articulo se presentan los aspectos relevantes de la experiencia acumulada en el proyecto.

Automatic Test Pattern Generator for Fuzzing Based on Finite State Machine

Directory of Open Access Journals (Sweden)

Ming-Hung Wang

2017-01-01

Full Text Available With the rapid development of the Internet, several emerging technologies are adopted to construct fancy, interactive, and user-friendly websites. Among these technologies, HTML5 is a popular one and is widely used in establishing modern sites. However, the security issues in the new web technologies are also raised and are worthy of investigation. For vulnerability investigation, many previous studies used fuzzing and focused on generation-based approaches to produce test cases for fuzzing; however, these methods require a significant amount of knowledge and mental efforts to develop test patterns for generating test cases. To decrease the entry barrier of conducting fuzzing, in this study, we propose a test pattern generation algorithm based on the concept of finite state machines. We apply graph analysis techniques to extract paths from finite state machines and use these paths to construct test patterns automatically. According to the proposal, fuzzing can be completed through inputting a regular expression corresponding to the test target. To evaluate the performance of our proposal, we conduct an experiment in identifying vulnerabilities of the input attributes in HTML5. According to the results, our approach is not only efficient but also effective for identifying weak validators in HTML5.

NDT developments in the CEGB [Central Electricity Generating Board] for turbine and generator rotor shafts

International Nuclear Information System (INIS)

Denby, D.

1990-01-01

In common with many utilities world-wide, the Central Electricity Generating Board (CEGB) has suffered problems of cracking in turbine and generator rotors, in a wide range of Units. The type of cracking that has stimulated most NDT development work is transverse cracking initiating at the outside of shafts, though axial cracking at turbine disc keyways has also required considerable effort. This paper describes current and recent developments of NDT techniques and equipment designed to provide early warning and assessment of service-induced cracks which could propagate to failure. The following developments are included: in-situ inspection of LP turbine rotor shafts by means of low-angle ultrasonic beams fired along the length of the shaft; techniques for detecting and measuring cracking in shrunk-on turbine disc keyways; a remote, in-situ technique for cracking initiating in the pole teeth of large generator rotors, aimed at detecting cracks while they are small enough for the rotor to be repaired; an in-situ technique for rapidly inspecting these same generator rotors for the presence of larger cracks, by an ultrasonic beam fired along the length of the shaft; ultrasonic in-situ inspection of generator rotor teeth directly under the shrunk-on end (retaining) rings

Major Dietary Patterns in Relation to General and Central Obesity among Chinese Adults

Directory of Open Access Journals (Sweden)

Canqing Yu

2015-07-01

Full Text Available Limited evidence exists for the association between diet pattern and obesity phenotypes among Chinese adults. In the present study, we analyzed the cross-sectional data from 474,192 adults aged 30–79 years from the China Kadoorie Biobank baseline survey. Food consumption was collected by an interviewer-administered questionnaire. Three dietary patterns were extracted by factor analysis combined with cluster analysis. After being adjusted for potential confounders, individuals following a traditional southern dietary pattern had the lowest body mass index (BMI and waist circumference (WC; the Western/new affluence dietary pattern had the highest BMI; and the traditional northern dietary pattern had the highest WC. Compared to the traditional southern dietary pattern in multivariable adjusted logistic models, individuals following a Western/new affluence dietary pattern had a significantly increased risk of general obesity (prevalence ratio (PR: 1.06, 95% confidence interval (CI: 1.03–1.08 and central obesity (PR: 1.07, 95% CI: 1.06–1.08. The corresponding risks for the traditional northern dietary pattern were 1.05 (1.02–1.09 and 1.17 (1.25–1.18, respectively. In addition, the associations were modified by lifestyle behaviors, and the combined effects with alcohol drinking, tobacco smoking, and physical activity were analyzed. Further prospective studies are needed to elucidate the diet-obesity relationships.

Major Dietary Patterns in Relation to General and Central Obesity among Chinese Adults

Science.gov (United States)

Yu, Canqing; Shi, Zumin; Lv, Jun; Du, Huaidong; Qi, Lu; Guo, Yu; Bian, Zheng; Chang, Liang; Tang, Xuefeng; Jiang, Qilian; Mu, Huaiyi; Pan, Dongxia; Chen, Junshi; Chen, Zhengming; Li, Liming

2015-01-01

Limited evidence exists for the association between diet pattern and obesity phenotypes among Chinese adults. In the present study, we analyzed the cross-sectional data from 474,192 adults aged 30–79 years from the China Kadoorie Biobank baseline survey. Food consumption was collected by an interviewer-administered questionnaire. Three dietary patterns were extracted by factor analysis combined with cluster analysis. After being adjusted for potential confounders, individuals following a traditional southern dietary pattern had the lowest body mass index (BMI) and waist circumference (WC); the Western/new affluence dietary pattern had the highest BMI; and the traditional northern dietary pattern had the highest WC. Compared to the traditional southern dietary pattern in multivariable adjusted logistic models, individuals following a Western/new affluence dietary pattern had a significantly increased risk of general obesity (prevalence ratio (PR): 1.06, 95% confidence interval (CI): 1.03–1.08) and central obesity (PR: 1.07, 95% CI: 1.06–1.08). The corresponding risks for the traditional northern dietary pattern were 1.05 (1.02–1.09) and 1.17 (1.25–1.18), respectively. In addition, the associations were modified by lifestyle behaviors, and the combined effects with alcohol drinking, tobacco smoking, and physical activity were analyzed. Further prospective studies are needed to elucidate the diet-obesity relationships. PMID:26184308

Direct generation of abruptly focusing vortex beams using a 3/2 radial phase-only pattern.

Science.gov (United States)

Davis, Jeffrey A; Cottrell, Don M; Zinn, Jonathan M

2013-03-20

Abruptly focusing Airy beams have previously been generated using a radial cubic phase pattern that represents the Fourier transform of the Airy beam. The Fourier transform of this pattern is formed using a system length of 2f, where f is the focal length of the Fourier transform lens. In this work, we directly generate these abruptly focusing Airy beams using a 3/2 radial phase pattern encoded onto a liquid crystal display. The resulting optical system is much shorter. In addition, we can easily produce vortex patterns at the focal point of these beams. Experimental results match theoretical predictions.

Comparison of large central and small decentralized power generation in India

Energy Technology Data Exchange (ETDEWEB)

None

1997-05-01

This reports evaluates two options for providing reliable power to rural areas in India. The benefits and costs are compared for biomass based distributed generation (DG) systems versus a 1200-MW central grid coal-fired power plant. The biomass based DG systems are examined both as alternatives to grid extension and as supplements to central grid power. The benefits are divided into three categories: those associated with providing reliable power from any source, those associated specifically with biomass based DG technology, and benefits of a central grid coal plant. The report compares the estimated delivered costs of electricity from the DG systems to those of the central plant. The analysis includes estimates for a central grid coal plant and four potential DG system technologies: Stirling engines, direct-fired combustion turbines, fuel cells, and biomass integrated gasification combined cycles. The report also discusses issues affecting India`s rural electricity demand, including economic development, power reliability, and environmental concerns. The results of the costs of electricity comparison between the biomass DG systems and the coal-fired central grid station demonstrated that the DG technologies may be able to produce very competitively priced electricity by the start of the next century. The use of DG technology may provide a practical means of addressing many rural electricity issues that India will face in the future. Biomass DG technologies in particular offer unique advantages for the environment and for economic development that will make them especially attractive. 58 refs., 31 figs.

Comparison of large central and small decentralized power generation in India

International Nuclear Information System (INIS)

1997-05-01

This reports evaluates two options for providing reliable power to rural areas in India. The benefits and costs are compared for biomass based distributed generation (DG) systems versus a 1200-MW central grid coal-fired power plant. The biomass based DG systems are examined both as alternatives to grid extension and as supplements to central grid power. The benefits are divided into three categories: those associated with providing reliable power from any source, those associated specifically with biomass based DG technology, and benefits of a central grid coal plant. The report compares the estimated delivered costs of electricity from the DG systems to those of the central plant. The analysis includes estimates for a central grid coal plant and four potential DG system technologies: Stirling engines, direct-fired combustion turbines, fuel cells, and biomass integrated gasification combined cycles. The report also discusses issues affecting India's rural electricity demand, including economic development, power reliability, and environmental concerns. The results of the costs of electricity comparison between the biomass DG systems and the coal-fired central grid station demonstrated that the DG technologies may be able to produce very competitively priced electricity by the start of the next century. The use of DG technology may provide a practical means of addressing many rural electricity issues that India will face in the future. Biomass DG technologies in particular offer unique advantages for the environment and for economic development that will make them especially attractive. 58 refs., 31 figs

F.P.G.: Fastbus Pattern Generator and Bus Configuration detector

International Nuclear Information System (INIS)

Cerrito, L.; Chorowicz, V.; Lebbolo, H.; Tesseidre, A.

1986-03-01

This module has been developed for the DELPHI-OUTER DETECTOR read out system environment. It is a Fastbus slave designed as a tool for syncronizing and monitoring a complex Fastbus system. F.P.G. is a programmable pattern generator with front panel TTL output: six on lemo cable and 24 on flat cable. Its frequency can range between 67 KHz and 20 MHz. It can be programmed to generate a signal on occurency of a particular configuration of the crate bus

Mitochondrial DNA pattern of the fine shrimp Metapenaeus elegans (De Man, 1907) in the lagoon of Segara Anakan, Central Java, using Hind III

Science.gov (United States)

Nugraha, Fitra Arya Dwi; Holil, Kholifah; Kurniawan, Nia

2017-05-01

Ecological damages to the Lagoon of Segara Anakan, Central Java, as well as large-scale and continuous exploitation are threatening the sustainability of fine shrimp, Metapenaeus elegans, and resources. Information in regards to genetic resources is crucial to establish long-term conservation programs and to preserve germplasm quality. This study aims to evaluate the number and size of the fragment which is digested with restriction enzyme Hind III. Seven individuals of Metapenaeus elegans from the Lagoon of Segara Anakan were examined using Hind III. Amplification of mitochondrial DNA resulted in 950 bp, and the digestion using Hind III generated four fragments consisting of 114 bp, 200 bp, 250 bp, and 386 bp, which formed a monomorphic pattern. The restriction pattern showed the probability of homozygosity of alleles that restricted using Hind III. Homozygosity indicates no variation of DNA sequence.

Diffractive elements for generating microscale laser beam patterns: a Y2K problem

Science.gov (United States)

Teiwes, Stephan; Krueger, Sven; Wernicke, Guenther K.; Ferstl, Margit

2000-03-01

Lasers are widely used in industrial fabrication for engraving, cutting and many other purposes. However, material processing at very small scales is still a matter of concern. Advances in diffractive optics could provide for laser systems that could be used for engraving or cutting of micro-scale patterns at high speeds. In our paper we focus on the design of diffractive elements which can be used for this special application. It is a common desire in material processing to apply 'discrete' as well as 'continuous' beam patterns. Especially, the latter case is difficult to handle as typical micro-scale patterns are characterized by bad band-limitation properties, and as speckles can easily occur in beam patterns. It is shown in this paper that a standard iterative design method usually fails to obtain diffractive elements that generate diffraction patterns with acceptable quality. Insights gained from an analysis of the design problems are used to optimize the iterative design method. We demonstrate applicability and success of our approach by the design of diffractive phase elements that generate a discrete and a continuous 'Y2K' pattern.

Study on the generation technology of Li brocade pattern mutant genes based on the AI and Java technology

Science.gov (United States)

Zhou, Yuping; Zhang, Qi

2018-04-01

In the information environment, digital and information processing to Li brocade patterns reveals an important means of Li ethnic style and inheriting the national culture. Adobe Illustrator CS3 and Java language were used in the paper to make "variation" processing to Li brocade patterns, and generate "Li brocade pattern mutant genes". The generation of pattern mutant genes includes color mutation, shape mutation, adding and missing transform, and twisted transform, etc. Research shows that Li brocade pattern mutant genes can be generated by using the Adobe Illustrator CS3 and the image processing tools of Java language edit, etc.

Caregiving Practice Patterns of Asian, Hispanic, and Non-Hispanic White American Family Caregivers of Older Adults Across Generations.

Science.gov (United States)

Miyawaki, Christina E

2016-03-01

This study is a cross-sectional investigation of caregiving practice patterns among Asian, Hispanic and non-Hispanic White American family caregivers of older adults across three immigrant generations. The 2009 California Health Interview Survey (CHIS) dataset was used, and 591 Asian, 989 Hispanic and 6537 non-Hispanic White American caregivers of older adults were selected. First, descriptive analyses of caregivers' characteristics, caregiving situations and practice patterns were examined by racial/ethnic groups and immigrant generations. Practice patterns measured were respite care use, hours and length of caregiving. Three hypotheses on caregiving patterns based on assimilation theory were tested and analyzed using logistic regression and generalized linear models by racial/ethnic groups and generations. Caregiving patterns of non-Hispanic White caregivers supported all three hypotheses regarding respite care use, caregiving hours and caregiving duration, showing less caregiving involvement in later generations. However, Asian and Hispanic counterparts showed mixed results. Third generation Asian and Hispanic caregivers used respite care the least and spent the most caregiving hours per week and had the longest caregiving duration compared to earlier generations. These caregiving patterns revealed underlying cultural values related to filial responsibility, even among later generations of caregivers of color. Findings suggest the importance of considering the cultural values of each racial/ethnic group regardless of generation when working with racially and ethnically diverse populations of family caregivers of older adults.

Production patterns of packaging waste categories generated at typical Mediterranean residential building worksites

Energy Technology Data Exchange (ETDEWEB)

González Pericot, N., E-mail: natalia.gpericot@upm.es [Escuela Técnica Superior de Edificación, Universidad Politécnica de Madrid, Calle Juan de Herrera n°6, 28040 Madrid (Spain); Villoria Sáez, P., E-mail: paola.villoria@upm.es [Escuela Técnica Superior de Edificación, Universidad Politécnica de Madrid, Calle Juan de Herrera n°6, 28040 Madrid (Spain); Del Río Merino, M., E-mail: mercedes.delrio@upm.es [Escuela Técnica Superior de Edificación, Universidad Politécnica de Madrid, Calle Juan de Herrera n°6, 28040 Madrid (Spain); Liébana Carrasco, O., E-mail: oscar.liebana@uem.es [Escuela de Arquitectura, Universidad Europea de Madrid, Calle Tajo s/n, 28670 Villaviciosa de Odón (Spain)

2014-11-15

Highlights: • On-site segregation level: 1.80%; training and motivation strategies were not effective. • 70% Cardboard waste: from switches and sockets during the building services stage. • 40% Plastic waste: generated during structures and partition works due to palletizing. • >50% Wood packaging waste, basically pallets, generated during the envelope works. - Abstract: The construction sector is responsible for around 28% of the total waste volume generated in Europe, which exceeds the amount of household waste. This has led to an increase of different research studies focusing on construction waste quantification. However, within the research studies made, packaging waste has been analyzed to a limited extent. This article focuses on the packaging waste stream generated in the construction sector. To this purpose current on-site waste packaging management has been assessed by monitoring ten Mediterranean residential building works. The findings of the experimental data collection revealed that the incentive measures implemented by the construction company to improve on-site waste sorting failed to achieve the intended purpose, showing low segregation ratios. Subsequently, through an analytical study the generation patterns for packaging waste are established, leading to the identification of the prevailing kinds of packaging and the products responsible for their generation. Results indicate that plastic waste generation maintains a constant trend throughout the whole construction process, while cardboard becomes predominant towards the end of the construction works with switches and sockets from the electricity stage. Understanding the production patterns of packaging waste will be beneficial for adapting waste management strategies to the identified patterns for the specific nature of packaging waste within the context of construction worksites.

Production patterns of packaging waste categories generated at typical Mediterranean residential building worksites

International Nuclear Information System (INIS)

González Pericot, N.; Villoria Sáez, P.; Del Río Merino, M.; Liébana Carrasco, O.

2014-01-01

Highlights: • On-site segregation level: 1.80%; training and motivation strategies were not effective. • 70% Cardboard waste: from switches and sockets during the building services stage. • 40% Plastic waste: generated during structures and partition works due to palletizing. • >50% Wood packaging waste, basically pallets, generated during the envelope works. - Abstract: The construction sector is responsible for around 28% of the total waste volume generated in Europe, which exceeds the amount of household waste. This has led to an increase of different research studies focusing on construction waste quantification. However, within the research studies made, packaging waste has been analyzed to a limited extent. This article focuses on the packaging waste stream generated in the construction sector. To this purpose current on-site waste packaging management has been assessed by monitoring ten Mediterranean residential building works. The findings of the experimental data collection revealed that the incentive measures implemented by the construction company to improve on-site waste sorting failed to achieve the intended purpose, showing low segregation ratios. Subsequently, through an analytical study the generation patterns for packaging waste are established, leading to the identification of the prevailing kinds of packaging and the products responsible for their generation. Results indicate that plastic waste generation maintains a constant trend throughout the whole construction process, while cardboard becomes predominant towards the end of the construction works with switches and sockets from the electricity stage. Understanding the production patterns of packaging waste will be beneficial for adapting waste management strategies to the identified patterns for the specific nature of packaging waste within the context of construction worksites

Towards pattern generation and chaotic series prediction with photonic reservoir computers

Science.gov (United States)

Antonik, Piotr; Hermans, Michiel; Duport, François; Haelterman, Marc; Massar, Serge

2016-03-01

Reservoir Computing is a bio-inspired computing paradigm for processing time dependent signals that is particularly well suited for analog implementations. Our team has demonstrated several photonic reservoir computers with performance comparable to digital algorithms on a series of benchmark tasks such as channel equalisation and speech recognition. Recently, we showed that our opto-electronic reservoir computer could be trained online with a simple gradient descent algorithm programmed on an FPGA chip. This setup makes it in principle possible to feed the output signal back into the reservoir, and thus highly enrich the dynamics of the system. This will allow to tackle complex prediction tasks in hardware, such as pattern generation and chaotic and financial series prediction, which have so far only been studied in digital implementations. Here we report simulation results of our opto-electronic setup with an FPGA chip and output feedback applied to pattern generation and Mackey-Glass chaotic series prediction. The simulations take into account the major aspects of our experimental setup. We find that pattern generation can be easily implemented on the current setup with very good results. The Mackey-Glass series prediction task is more complex and requires a large reservoir and more elaborate training algorithm. With these adjustments promising result are obtained, and we now know what improvements are needed to match previously reported numerical results. These simulation results will serve as basis of comparison for experiments we will carry out in the coming months.

Correlation between vegetation pattern and microtopography in periglacial areas of the Central Alps

Directory of Open Access Journals (Sweden)

Gerdol, Renato

1990-06-01

Full Text Available The distributional patterns of plant species were analyzed within periglacial microforms belonging to the collective groups of patterned grounds and sorted stripes In the Ortles-Cevedale group (Lombardy, Italy. The edges of primitive polygons are practically free of vegetation, whilst the central areas are colonized by pioneer plants of detritic slopes. This is clearly correlated with a low degree of sediment sorting. The morphological evolution of the forms proceeds at a faster rate at the edge of polygons than in the central areas. Vegetation, on the other hand, colonizes the coarse debris at the polygons’ edges slowly but colonizes the fine material in the central areas actively. The centre of the most evolved polygons is covered by a carpet of Salix herbacea. Age determinations of Salix shoots are not useful for dating purposes, but provide Information about the local microclimate.

[es] Se han analizado los modelos de distribución de especies vegetales en microformas periglaciares pertenecientes al tipo de suelos estructurales en el Ortles-Cevedale (Lombardía, Italia. Los límites de los polígonos de piedras están prácticamente libres de vegetación, mientras las áreas centrales están colonizadas por plantas pioneras de laderas pedregosas. La evolución morfológica actúa a mayor velocidad en el borde de los polígonos que en las áreas centrales. Por otro lado, la vegetación coloniza lentamente los bordes de los polígonos, y más activamente las zonas centrales. El centro de la mayoría de los polígonos está cubierto por un manto de Salix herbacea. La determinación de la edad de los vástagos de Salix no ha sido un método útil a efectos cronológicos, pero proporciona información sobre el microclima local.
[fr] On étude les modèles de distribution d'espèces végétaux dans microformes périglaciaires appartenants au type de sols structurales dans l'Ortles-Cevedale (Lombardie

Motor unit firing rate patterns during voluntary muscle force generation: a simulation study

Science.gov (United States)

Hu, Xiaogang; Rymer, William Z.; Suresh, Nina L.

2014-04-01

Objective. Muscle force is generated by a combination of motor unit (MU) recruitment and changes in the discharge rate of active MUs. There have been two basic MU recruitment and firing rate paradigms reported in the literature, which describe the control of the MUs during force generation. The first (termed the reverse ‘onion skin’ profile), exhibits lower firing rates for lower threshold units, with higher firing rates occurring in higher threshold units. The second (termed the ‘onion skin’ profile), exhibits an inverse arrangement, with lower threshold units reaching higher firing rates. Approach. Using a simulation of the MU activity in a hand muscle, this study examined the force generation capacity and the variability of the muscle force magnitude at different excitation levels of the MU pool under these two different MU control paradigms. We sought to determine which rate/recruitment scheme was more efficient for force generation, and which scheme gave rise to the lowest force variability. Main results. We found that the force output of both firing patterns leads to graded force output at low excitation levels, and that the force generation capacity of the two different paradigms diverged around 50% excitation. In the reverse ‘onion skin’ pattern, at 100% excitation, the force output reached up to 88% of maximum force, whereas for the ‘onion skin’ pattern, the force output only reached up to 54% of maximum force at 100% excitation. The force variability was lower at the low to moderate force levels under the ‘onion skin’ paradigm than with the reverse ‘onion skin’ firing patterns, but this effect was reversed at high force levels. Significance. This study captures the influence of MU recruitment and firing rate organization on muscle force properties, and our results suggest that the different firing organizations can be beneficial at different levels of voluntary muscle force generation and perhaps for different tasks.

Eigenvector centrality mapping for analyzing connectivity patterns in fMRI data of the human brain.

Directory of Open Access Journals (Sweden)

Gabriele Lohmann

Full Text Available Functional magnetic resonance data acquired in a task-absent condition ("resting state" require new data analysis techniques that do not depend on an activation model. In this work, we introduce an alternative assumption- and parameter-free method based on a particular form of node centrality called eigenvector centrality. Eigenvector centrality attributes a value to each voxel in the brain such that a voxel receives a large value if it is strongly correlated with many other nodes that are themselves central within the network. Google's PageRank algorithm is a variant of eigenvector centrality. Thus far, other centrality measures - in particular "betweenness centrality" - have been applied to fMRI data using a pre-selected set of nodes consisting of several hundred elements. Eigenvector centrality is computationally much more efficient than betweenness centrality and does not require thresholding of similarity values so that it can be applied to thousands of voxels in a region of interest covering the entire cerebrum which would have been infeasible using betweenness centrality. Eigenvector centrality can be used on a variety of different similarity metrics. Here, we present applications based on linear correlations and on spectral coherences between fMRI times series. This latter approach allows us to draw conclusions of connectivity patterns in different spectral bands. We apply this method to fMRI data in task-absent conditions where subjects were in states of hunger or satiety. We show that eigenvector centrality is modulated by the state that the subjects were in. Our analyses demonstrate that eigenvector centrality is a computationally efficient tool for capturing intrinsic neural architecture on a voxel-wise level.

Continuities and changes in infant attachment patterns across two generations.

Science.gov (United States)

Raby, K Lee; Steele, Ryan D; Carlson, Elizabeth A; Sroufe, L Alan

2015-01-01

This study examined the intergenerational continuities and changes in infant attachment patterns within a higher-risk longitudinal sample of 55 female participants born into poverty. Infant attachment was assessed using the Strange Situation when participants were 12 and 18 months as well as several decades later with participants' children. Paralleling earlier findings from this sample on the stability of attachment patterns from infancy to young adulthood, results provided evidence for intergenerational continuities in attachment disorganization but not security. Children of adults with histories of infant attachment disorganization were at an increased risk of forming disorganized attachments. Although changes in infant attachment patterns across the two generations were not correlated with individuals' caregiving experiences or interpersonal stresses and supports during childhood and adolescence, higher quality social support during adulthood was associated with intergenerational changes from insecure to secure infant-caregiver attachment relationships.

Timber harvesting patterns for major states in the central, northern, and mid-Atlantic hardwood regions

Science.gov (United States)

William G. Luppold; Matthew S. Bumgardner

2018-01-01

Timber harvesting is a major disturbance agent influencing the composition and structure of eastern hardwood forests. To better understand timber harvesting practices, we examined roundwood harvesting patterns in 13 eastern states in the Central, Mid-Atlantic, and Northern regions that contained high proportional volumes of hardwood in their forest inventories. Nearly...

Pattern of Colon Cancer Lymph Node Metastases in Patients Undergoing Central Mesocolic Lymph Node Excision

DEFF Research Database (Denmark)

Bertelsen, Claus A; Kirkegaard-Klitbo, Anders; Nielsen, Mingyuan

2016-01-01

BACKGROUND: Extended mesocolic lymph node dissection in colon cancer surgery seems to improve oncological outcome. A possible reason might be related to metastases in the central mesocolic lymph nodes. OBJECTIVE: The purpose of this study was to describe the pattern of mesocolic lymph node...... metastases, particularly in central lymph nodes, and the risk of skip, aberrant, and gastrocolic ligament metastases as the argument for performing extended lymph node dissection. DATA SOURCES: EMBASE and PubMed were searched using the terms colon or colorectal with sentinel node, lymph node mapping, or skip...... node; lymph node resection colon; and complete or total and mesocolic excision. STUDY SELECTION: Studies describing the risk of metastases in central, skip, aberrant, and gastrocolic ligament lymph node metastases from colon adenocarcinomas in 10 or more patients were included. No languages were...

Simulation of an offshore wind farm using fluid power for centralized electricity generation

Directory of Open Access Journals (Sweden)

A. Jarquin Laguna

2017-07-01

Full Text Available A centralized approach for electricity generation within a wind farm is explored through the use of fluid power technology. This concept considers a new way of generation, collection and transmission of wind energy inside a wind farm, in which electrical conversion does not occur during any intermediate conversion step before the energy has reached the offshore central platform. A numerical model was developed to capture the relevant physics from the dynamic interaction between different turbines coupled to a common hydraulic network and controller. This paper presents a few examples of the time domain simulation results for a hypothetical hydraulic wind farm subject to turbulent wind conditions. The performance and operational parameters of individual turbines are compared with those of a reference wind farm based on conventional wind turbine generator technology using the same wind farm layout and environmental conditions. For the presented case studies, results indicate that the individual wind turbines are able to operate within operational limits. Despite the stochastic turbulent wind conditions and wake effects, the hydraulic wind farm is able to produce electricity with reasonable performance in both below and above rated conditions. With the current pressure control concept, a continuous operation of the hydraulic wind farm is shown including the full stop of one or more turbines.

Walking Pattern Generation of Dual-Arm Mobile Robot Using Preview Controller

OpenAIRE

P. Wu; W. Wu

2012-01-01

Based on the stability request of robot’s moving on the ground, the motion planning of dual-arm mobile robot when moving on the ground is studied and the preview control system is applied in the robot walking pattern generation. Direct question of robot kinematics in the extended task space is analyzed according to Degrees of Freedom configuration of the dual-arm mobile robot. It is proved that the preview control system could be used in the generation of robot Center of Mass forward trajecto...

Patterns of forest use and endemism in resident bird communities of north-central Michoacan, Mexico

Science.gov (United States)

Santiago Garcia; Deborah M. Finch; Gilberto Chavez. Leon

1998-01-01

We compared breeding avian communities among 11 habitat types in north-central Michoacan, Mexico, to determine patterns of forest use by endemic and nonendemic resident species. Point counts of birds and vegetation measurements were conducted at 124 sampling localities from May through July, in 1994 and 1995. Six native forest types sampled were pine, pine-oak, oak-...

The repair of an electric generator at the Patla hydro central; Reparacion de un generador de la central hidroelectrica de Patla

Energy Technology Data Exchange (ETDEWEB)

Vazquez Hernandez, Roman [Luz y Fuerza del Centro, Mexico, D. F. (Mexico)

1997-12-31

This document describes the repair of the Generator Number 1 of the system of the Unit No. 1 of the Patla Hydro Power Central in Mexico. The tests that were conducted to determine the fault and the location of the same are shown. Mention is made of the fault repair options and the stages in one of the options are described, since it is the one that better covers the expectations for the satisfactory repair of the generator. Finally the commissioning test is described and it is concluded that an increment of 92% (14 MW) in the generation capacity of the unit was achieved, being this the first time a repair of this type is made of generating units [Espanol] Este documento describe la reparacion del generador numero 1 del sistema de la unidad numero 1 de la central hidroelectrica de Patla en Mexico. Se muestran las pruebas que se hicieron para determinar la falla y localizacion de la misma. Se mencionan las alternativas de reparacion de la falla y se describen las etapas de una de las alternativas, ya que es la que cubre mejor las expectativas para la reparacion satisfactoria del generador. Por ultimo se describe la prueba de puesta en servicio y se concluye en que se logro un aumento de la capacidad de generacion de la unidad en un 92% (14 MW), siendo la primera vez que se hace una reparacion de este tipo de unidades generadoras

Generating potentially nilpotent full sign patterns

NARCIS (Netherlands)

Kim, I.J.; Olesky, D.D.; Shader, B.L.; Driessche, van den P.; Holst, van der H.; Vander Meulen, K.N.

2009-01-01

A sign pattern is a matrix with entries in {+,-, 0}. A full sign pattern has no zero entries. The refined inertia of a matrix pattern is defined and techniques are developed for constructing potentially nilpotent full sign patterns. Such patterns are spectrally arbitrary. These techniques can also

BUILDOUT AND UPGRADE OF CENTRAL EMERGENCY GENERATOR SYSTEM, GENERATOR 3 AND 4 ELECTRICAL INSTALLATION

Energy Technology Data Exchange (ETDEWEB)

Gary D. Seifert; G. Shawn West; Kurt S. Myers; Jim Moncur

2006-07-01

SECTION 01000—SUMMARY OF WORK PART 1—GENERAL 1.1 SUMMARY The work to be performed under this project consists of providing the labor, equipment, and materials to perform "Buildout and Upgrade of Central Emergency Generator System, Generator 3 and 4 Electrical Installation" for the National Aeronautics and Space Administration at the Dryden Flight Research Center (NASA/DFRC), Edwards, California 93523. All modifications to existing substations and electrical distribution systems are the responsibility of the contractor. It is the contractor’s responsibility to supply a complete and functionally operational system. The work shall be performed in accordance with these specifications and the related drawings. The work of this project is defined by the plans and specifications contained and referenced herein. This work specifically includes but is not limited to the following: Scope of Work - Installation 1. Install all electrical wiring and controls for new generators 3 and 4 to match existing electrical installation for generators 1 and 2 and in accordance with drawings. Contractor shall provide as-built details for electrical installation. 2. Install battery charger systems for new generators 3 and 4 to match existing battery charging equipment and installation for generators 1 and 2. This may require exchange of some battery charger parts already on-hand. Supply power to new battery chargers from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. 3. Install electrical wiring for fuel/lube systems for new generators 3 and 4 to match existing installation for generators 1 and 2. Supply power to lube oil heaters and fuel system (day tanks) from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. Add any conduits necessary to

Elevated dopamine alters consummatory pattern generation and increases behavioral variability during learning

Directory of Open Access Journals (Sweden)

Mark A. Rossi

2015-05-01

Full Text Available The role of dopamine in controlling behavior remains poorly understood. In this study we examined licking behavior in an established hyperdopaminergic mouse model—dopamine transporter knockout (DAT KO mice. DAT KO mice showed higher rates of licking, which is due to increased perseveration of licking in a bout. By contrast, they showed increased individual lick durations, and reduced inter-lick-intervals. During extinction, both KO and control mice transiently increased variability in lick pattern generation while reducing licking rate, yet they showed very different behavioral patterns. Control mice gradually increased lick duration as well as variability. By contrast, DAT KO mice exhibited more immediate (within 10 licks adjustments—an immediate increase in lick duration variability, as well as more rapid extinction. These results suggest that the level of dopamine can modulate the persistence and pattern generation of a highly stereotyped consummatory behavior like licking, as well as new learning in response to changes in environmental feedback. Increased dopamine in DAT KO mice not only increased perseveration of bouts and individual lick duration, but also increased the behavioral variability in response to the extinction contingency and the rate of extinction.

Modeling urbanization patterns at a global scale with generative adversarial networks

Science.gov (United States)

Albert, A. T.; Strano, E.; Gonzalez, M.

2017-12-01

Current demographic projections show that, in the next 30 years, global population growth will mostly take place in developing countries. Coupled with a decrease in density, such population growth could potentially double the land occupied by settlements by 2050. The lack of reliable and globally consistent socio-demographic data, coupled with the limited predictive performance underlying traditional urban spatial explicit models, call for developing better predictive methods, calibrated using a globally-consistent dataset. Thus, richer models of the spatial interplay between the urban built-up land, population distribution and energy use are central to the discussion around the expansion and development of cities, and their impact on the environment in the context of a changing climate. In this talk we discuss methods for, and present an analysis of, urban form, defined as the spatial distribution of macroeconomic quantities that characterize a city, using modern machine learning methods and best-available remote-sensing data for the world's largest 25,000 cities. We first show that these cities may be described by a small set of patterns in radial building density, nighttime luminosity, and population density, which highlight, to first order, differences in development and land use across the world. We observe significant, spatially-dependent variance around these typical patterns, which would be difficult to model using traditional statistical methods. We take a first step in addressing this challenge by developing CityGAN, a conditional generative adversarial network model for simulating realistic urban forms. To guide learning and measure the quality of the simulated synthetic cities, we develop a specialized loss function for GAN optimization that incorporates standard spatial statistics used by urban analysis experts. Our framework is a stark departure from both the standard physics-based approaches in the literature (that view urban forms as fractals with a

Human spinal locomotor control is based on flexibly organized burst generators.

Science.gov (United States)

Danner, Simon M; Hofstoetter, Ursula S; Freundl, Brigitta; Binder, Heinrich; Mayr, Winfried; Rattay, Frank; Minassian, Karen

2015-03-01

samples of rhythmic patterns. The basic activation patterns can be interpreted as central drives implemented by spinal burst generators that impose specific spatiotemporally organized activation on the lumbosacral motor neuron pools. Our data thus imply that the human lumbar spinal cord circuits can form burst-generating elements that flexibly combine to obtain a wide range of locomotor outputs from a constant, repetitive input. It may be possible to use this flexibility to incorporate specific adaptations to gait and stance to improve locomotor control, even after severe central nervous system damage. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

High efficiency particulate air filter technology from 1980 to 1985 in the Central Electricity Generating Board

International Nuclear Information System (INIS)

Skledon, R.; Taylor, S.; Fern, C.; Stead, M.

1986-01-01

This paper examines at the Central Electricity Generating Board's methods of High Efficiency Particulate Air (1,700 m 3 /hr) filter testing from conception to the present day. The choice of the test and the early results are looked at followed by the development using new test equipment for checking ladderframe systems. The need for the drawing up of the Central Electricity Generating Board 743401 Standard for filter manufacture and its effect on full implementation is looked into. The advantages and disadvantages of our test procedures are reflected upon and the future developments in test methods and filters for use by the C.E.G.B. in their power stations are discussed. (author)

Optimisation of a Kalina cycle for a central receiver solar thermal power plant with direct steam generation

DEFF Research Database (Denmark)

Modi, Anish; Haglind, Fredrik

2014-01-01

Central receiver solar thermal power plants are regarded as one of the promising ways to generate electricity in near future. They offer the possibility of using high temperatures and pressures to achieve high efficiencies with standard power cycles. A direct steam generation approach can be used...

Enhanced seasonal predictability of the summer mean temperature in Central Europe favored by new dominant weather patterns

Science.gov (United States)

Hoffmann, P.

2018-04-01

In this study two complementary approaches have been combined to estimate the reliability of the data-driven seasonal predictability of the meteorological summer mean temperature (T_{JJA}) over Europe. The developed model is based on linear regressions and uses early season predictors to estimate the target value T_{JJA}. We found for the Potsdam (Germany) climate station that the monthly standard deviations (σ) from January to April and the temperature mean ( m) in April are good predictors to describe T_{JJA} after 1990. However, before 1990 the model failed. The core region where this model works is the north-eastern part of Central Europe. We also analyzed long-term trends of monthly Hess/Brezowsky weather types as possible causes of the dynamical changes. In spring, a significant increase of the occurrences for two opposite weather patterns was found: Zonal Ridge across Central Europe (BM) and Trough over Central Europe (TRM). Both currently make up about 30% of the total alternating weather systems over Europe. Other weather types are predominantly decreasing or their trends are not significant. Thus, the predictability may be attributed to these two weather types where the difference between the two Z500 composite patterns is large. This also applies to the north-eastern part of Central Europe. Finally, the detected enhanced seasonal predictability over Europe is alarming, because severe side effects may occur. One of these are more frequent climate extremes in summer half-year.

Determination of activity by gamma spectrometry of radionuclides present in drums of residues generated in nuclear centrals

International Nuclear Information System (INIS)

Aguiar, J.C.; Fernandez, J.

2006-01-01

The generation of radioactive residuals in nuclear centrals as CNA I (Atucha I Nuclear Central) and CNE (Embalse Nuclear Central) makes that the measurement of those radionuclides has been a previous stage to the waste management. A method used in those nuclear centrals it is the gamma spectrometry with HPGe detectors, previous to the immobilization of the residual in a cemented matrix, with this the contact with the external agents and its possible dispersion to the atmosphere in the short term is avoided. The ARN (Nuclear Regulatory Authority) of Argentina it carries out periodically intercomparisons and evaluations of the measurement and procedures systems used in the nuclear power stations for the correct measurement and determination of activity of radioactive residuals by gamma spectrometry. In this work an independent method of measurement is exposed to the nuclear power stations. To determine the activity of the residuals by gamma spectrometry deposited in drums, it is required of the precise knowledge of the efficiency curve for such geometry and matrix. Due to the RNA doesn't have a pattern of these characteristics, a mathematical model has been used to obtain this efficiency curve. For it, it is necessary to determine previously: 1) the geometric efficiency or solid angle sustained by the source-detector system (drum-detector) applying a mathematical model described in this work. 2) To estimate the auto-attenuation factor that present the photons in the cemented matrix, these calculations are carried out with a simple equation and its are verified with the Micro Shield 6.10 program. The container commonly used by these nuclear power stations its are drums for 220 liters constructed with SAE 1010 steel and with a thickness of 0.127 cm, with an approximate weight 7.73 Kg., internal diameter of 57.1 cm, and height: 87 cm. The results obtained until the moment register a discrepancy from 5 to 10% with relationship to the measurements carried out by the

Development of pattern recognition algorithms for the central drift chamber of the Belle II detector

Energy Technology Data Exchange (ETDEWEB)

Trusov, Viktor

2016-11-04

In this thesis, the development of one of the pattern recognition algorithms for the Belle II experiment based on conformal and Legendre transformations is presented. In order to optimize the performance of the algorithm (CPU time and efficiency) specialized processing steps have been introduced. To show achieved results, Monte-Carlo based efficiency measurements of the tracking algorithms in the Central Drift Chamber (CDC) has been done.

Interactions of glyphosate use with farm characteristics and cropping patterns in Central Europe.

Science.gov (United States)

Wiese, Armin; Schulte, Michael; Theuvsen, Ludwig; Steinmann, Horst-Henning

2018-05-01

Although glyphosate is the most widely used herbicide in the European Union, little is known about the patterns of its usage in arable farming. Therefore, a nationwide survey of 2026 German farmers was analysed to obtain further knowledge about glyphosate applications in conventional European arable farming. Given its broad range of agri-environmental and farm-type conditions, Germany can be regarded as a suitable study region to represent Central European farming. The growing season 2013/2014 was set as a reference. Farmers who participated in the survey employ diverse patterns of glyphosate use. While 23% stated that they did not use glyphosate in the season in question, others applied glyphosate to their total arable area. However, most applications occurred on specific parts of the farm. Application patterns of oilseed rape, winter wheat, maize and sugar beet were studied in detail, and U-shaped distributions of glyphosate use intensity were observed. The effects of farm type and management practices on glyphosate use patterns were mixed in the various crops. Motivation for glyphosate use differs widely within the farming community. Agricultural researchers, extension services and policy makers are recommended to mitigate vulnerabilities associated with glyphosate use, such as routine spraying and practices that increase selection pressure for the evolution of glyphosate-resistant weeds. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Distributed plasticity of locomotor pattern generators in spinal cord injured patients.

Science.gov (United States)

Grasso, Renato; Ivanenko, Yuri P; Zago, Myrka; Molinari, Marco; Scivoletto, Giorgio; Castellano, Vincenzo; Macellari, Velio; Lacquaniti, Francesco

2004-05-01

Recent progress with spinal cord injured (SCI) patients indicates that with training they can recover some locomotor ability. Here we addressed the question of whether locomotor responses developed with training depend on re-activation of the normal motor patterns or whether they depend on learning new motor patterns. To this end we recorded detailed kinematic and EMG data in SCI patients trained to step on a treadmill with body-weight support (BWST), and in healthy subjects. We found that all patients could be trained to step with BWST in the laboratory conditions, but they used new coordinative strategies. Patients with more severe lesions used their arms and body to assist the leg movements via the biomechanical coupling of limb and body segments. In all patients, the phase-relationship of the angular motion of the different lower limb segments was very different from the control, as was the pattern of activity of most recorded muscles. Surprisingly, however, the new motor strategies were quite effective in generating foot motion that closely matched the normal in the laboratory conditions. With training, foot motion recovered the shape, the step-by-step reproducibility, and the two-thirds power relationship between curvature and velocity that characterize normal gait. We mapped the recorded patterns of muscle activity onto the approximate rostrocaudal location of motor neuron pools in the human spinal cord. The reconstructed spatiotemporal maps of motor neuron activity in SCI patients were quite different from those of healthy subjects. At the end of training, the locomotor network reorganized at both supralesional and sublesional levels, from the cervical to the sacral cord segments. We conclude that locomotor responses in SCI patients may not be subserved by changes localized to limited regions of the spinal cord, but may depend on a plastic redistribution of activity across most of the rostrocaudal extent of the spinal cord. Distributed plasticity underlies

Assessment of CLIGEN precipitation and storm pattern generation under four precipitation depth categories in China

Science.gov (United States)

CLIGEN (CLImate GENerator) is a widely used stochastic weather generator to simulate continuous daily precipitation and storm pattern information for hydrological and soil erosion models. Although CLIGEN has been tested in several regions in the world, thoroughly assessment before applying it to Chi...

Intake-to-delivered-energy ratios for central station and distributed electricity generation in California

International Nuclear Information System (INIS)

Heath, Garvin A.; Nazaroff, William W.

2007-01-01

In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a shift toward distributed electricity generation. Atmospheric Environment 40, 7164-7177]. The present paper builds on that study, exploring pollutant- and technology-specific aspects of population inhalation exposure from electricity generation. We compare California's existing CS-based system to one that is more reliant on DG units sited in urban areas. We use Gaussian plume modeling and a GIS-based exposure analysis to assess 25 existing CSs and 11 DG sources hypothetically located in the downtowns of California's most populous cities. We consider population intake of three pollutants - PM 2.5 , NO x and formaldehyde - directly emitted by five DG technologies - natural gas (NG)-fired turbines, NG internal combustion engines (ICE), NG microturbines, diesel ICEs, and fuel cells with on-site NG reformers. We also consider intake of these pollutants from existing CS facilities, most of which use large NG turbines, as well as from hypothetical facilities located at these same sites but meeting California's best-available control technology standards. After systematically exploring the sensitivity of iF to pollutant decay rate, the iFs for each of the three pollutants for all DG and CS cases are estimated. To efficiently compare the pollutant- and technology-specific exposure potential on an appropriate common basis, a new metric is introduced and evaluated: the intake-to-delivered-energy ratio (IDER). The IDER expresses the mass of pollutant inhaled by an exposed population owing to emissions from an electricity generation unit per quantity of electric

Intake-to-delivered-energy ratios for central station and distributed electricity generation in California

Science.gov (United States)

Heath, Garvin A.; Nazaroff, William W.

In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a shift toward distributed electricity generation. Atmospheric Environment 40, 7164-7177]. The present paper builds on that study, exploring pollutant- and technology-specific aspects of population inhalation exposure from electricity generation. We compare California's existing CS-based system to one that is more reliant on DG units sited in urban areas. We use Gaussian plume modeling and a GIS-based exposure analysis to assess 25 existing CSs and 11 DG sources hypothetically located in the downtowns of California's most populous cities. We consider population intake of three pollutants—PM 2.5, NO x and formaldehyde—directly emitted by five DG technologies—natural gas (NG)-fired turbines, NG internal combustion engines (ICE), NG microturbines, diesel ICEs, and fuel cells with on-site NG reformers. We also consider intake of these pollutants from existing CS facilities, most of which use large NG turbines, as well as from hypothetical facilities located at these same sites but meeting California's best-available control technology standards. After systematically exploring the sensitivity of iF to pollutant decay rate, the iFs for each of the three pollutants for all DG and CS cases are estimated. To efficiently compare the pollutant- and technology-specific exposure potential on an appropriate common basis, a new metric is introduced and evaluated: the intake-to-delivered-energy ratio (IDER). The IDER expresses the mass of pollutant inhaled by an exposed population owing to emissions from an electricity generation unit per quantity of electric

Valuable Subversions: Gendered Generativity and Sorcerous Production in Central Mozambique

Directory of Open Access Journals (Sweden)

Bjørn Enge Bertelsen

2016-11-01

Full Text Available How is one to analyze the existence of a subterranean dwarfish couple (zwidoma occupying the space underneath cooking places and whose central purpose is to reinforce a market woman's sales - but simultaneously feeding off her very body? Using urban and rural ethnographic material from central Mozambique, where such assemblages comprising the zwidoma and a woman are integral to economic life and social orders, this article contextualizes such constellations - effectively interferences within various domains of value - by undertaking an analysis of gendered modalities of generativity. Further, by meditating on various understandings of cosmology and, ultimately, the dynamics constituting the realms of the real, it presents an alternative to influential analyses of capitalism, such as the notion of "occult economies." An argument is made not only for value's dynamic and changeable nature but also for the necessity to appreciate instances of its subversion with destructive effects. The article underlines, therefore, how such subversions of value, in various forms, is in line with Tsing's (2015 general argument that critical explorations of capitalism and regimes of valuation and production are best undertaken in peri-capitalist zones- such as urban and rural Mozambique.

Overhaul of the generator of the hydroelectric central station Ingeniero Carlos Ramirez Ulloa; Rehabilitacion del generador de la unidad 2 de la central hidroelectrica ingeniero Carlos Ramirez Ulloa

Energy Technology Data Exchange (ETDEWEB)

Robles Pimentel, Edgar [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Garcia Hernandez, Javier [Comision Federal de Electricidad, Mexico, D. F. (Mexico)

1997-12-31

In November 1995, the failure of the Unit 2 generator at the hydroelectric central station Ingeniero Carlos Ramirez Ulloa, El Caracol, occurred. The accident forced to carry out its overhaul. Here are presented the technical problems faced during the overhaul of the generator and analyzed the implemented solutions. [Espanol] En noviembre de 1995 ocurrio la falla del generador de la unidad 2 de la central hidroelectrica Ing. Carlos Ramirez Ulloa, El Caracol. El accidente obligo a llevar a cabo su rehabilitacion. Se presentan los problemas tecnicos enfrentados durante la rehabilitacion del generador y se discuten las soluciones implementadas.

Overhaul of the generator of the hydroelectric central station Ingeniero Carlos Ramirez Ulloa; Rehabilitacion del generador de la unidad 2 de la central hidroelectrica ingeniero Carlos Ramirez Ulloa

Energy Technology Data Exchange (ETDEWEB)

Robles Pimentel, Edgar [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Garcia Hernandez, Javier [Comision Federal de Electricidad, Mexico, D. F. (Mexico)

1998-12-31

In November 1995, the failure of the Unit 2 generator at the hydroelectric central station Ingeniero Carlos Ramirez Ulloa, El Caracol, occurred. The accident forced to carry out its overhaul. Here are presented the technical problems faced during the overhaul of the generator and analyzed the implemented solutions. [Espanol] En noviembre de 1995 ocurrio la falla del generador de la unidad 2 de la central hidroelectrica Ing. Carlos Ramirez Ulloa, El Caracol. El accidente obligo a llevar a cabo su rehabilitacion. Se presentan los problemas tecnicos enfrentados durante la rehabilitacion del generador y se discuten las soluciones implementadas.

Relating land use patterns to stream nutrient levels in red soil agricultural catchments in subtropical central China.

Science.gov (United States)

Wang, Yi; Li, Yong; Liu, Xinliang; Liu, Feng; Li, Yuyuan; Song, Lifang; Li, Hang; Ma, Qiumei; Wu, Jinshui

2014-09-01

Land use has obvious influence on surface water quality; thus, it is important to understand the effects of land use patterns on surface water quality. This study explored the relationships between land use patterns and stream nutrient levels, including ammonium-N (NH4 (+)-N), nitrate-N (NO3 (-)-N), total N (TN), dissolved P (DP), and total P (TP) concentrations, in one forest and 12 agricultural catchments in subtropical central China. The results indicated that the TN concentrations ranged between 0.90 and 6.50 mg L(-1) and the TP concentrations ranged between 0.08 and 0.53 mg L(-1), showing that moderate nutrient pollution occurred in the catchments. The proportional areal coverages of forests, paddy fields, tea fields, residential areas, and water had distinct effects on stream nutrient levels. Except for the forest, all studied land use types had a potential to increase stream nutrient levels in the catchments. The land use pattern indices at the landscape level were significantly correlated to N nutrients but rarely correlated to P nutrients in stream water, whereas the influence of the land use pattern indices at the class level on stream water quality differentiated among the land use types and nutrient species. Multiple regression analysis suggested that land use pattern indices at the class level, including patch density (PD), largest patch index (LPI), mean shape index (SHMN), and mean Euclidian nearest neighbor distance (ENNMN), played an intrinsic role in influencing stream nutrient quality, and these four indices explained 35.08 % of the variability of stream nutrient levels in the catchments (pstream nutrient pollution in subtropical central China.

Simulation of an offshore wind farm using fluid power for centralized electricity generation

International Nuclear Information System (INIS)

Jarquin-Laguna, A

2016-01-01

A centralized approach for electricity generation within a wind farm is explored through the use of fluid power technology. This concept considers a new way of generation, collection and transmission of wind energy inside a wind farm, in which electrical conversion does not occur during any intermediate conversion step before the energy has reached the offshore central platform. A numerical model was developed to capture the relevant physics from the dynamic interaction between different turbines coupled to a common hydraulic network and controller. This paper presents two examples of the time-domain simulation results for an hypothetical hydraulic wind farm subject to turbulent wind conditions. The performance and operational parameters of individual turbines are compared with those of a reference wind farm with conventional technology turbines, using the same wind farm layout and environmental conditions. For the presented case study, results indicate that the individual wind turbines are able to operate within operational limits with the current pressure control concept. Despite the stochastic turbulent wind input and wake effects, the hydraulic wind farm is able to produce electricity with reasonable performance in both below and above rated conditions. (paper)

Generation patterns of four groups of cholinergic neurons in rat cervical spinal cord: a combined tritiated thymidine autoradiographic and choline acetyltransferase immunocytochemical study

International Nuclear Information System (INIS)

Phelps, P.E.; Barber, R.P.; Vaughn, J.E.

1988-01-01

This report examines the generation of cholinergic neurons in the spinal cord in order to determine whether the transmitter phenotype of neurons is associated with specific patterns of neurogenesis. Previous immunocytochemical studies identified four groups of choline acetyltransferase (ChAT)-positive neurons in the cervical enlargement of the rat spinal cord. These cell groups vary in both somatic size and location along the previously described ventrodorsal neurogenic gradient of the spinal cord. Thus, large (and small) motoneurons are located in the ventral horn, medium-sized partition cells are found in the intermediate gray matter, small central canal cluster cells are situated within lamina X, and small dorsal horn neurons are scattered predominantly through laminae III-V. The relationships among the birthdays of these four subsets of cholinergic neurons have been examined by combining 3H-thymidine autoradiography and ChAT immunocytochemistry. Embryonic day 11 was the earliest time that neurons were generated within the cervical enlargement. Large and small ChAT-positive motoneurons were produced on E11 and 12, with 70% of both groups being born on E11. ChAT-positive partition cells were produced between E11 and 13, with their peak generation occurring on E12. Approximately 70% of the cholinergic central canal cluster and dorsal horn cells were born on E13, and the remainder of each of these groups was generated on E14. Other investigators have shown that all neurons within the rat cervical spinal cord are produced in a ventrodorsal sequence between E11 and E16. In contrast, ChAT-positive neurons are born only from E11 to E14 and are among the earliest cells generated in the ventral, intermediate, and dorsal subdivisions of the spinal cord

Spatial pattern of a subalpine forest-alpine pasture ecotone (Las Cutas, Ordesa, Central Pyrenees)

OpenAIRE

Camarero, J. J.; Gutierrez, E.

1999-01-01

We describe the spatial pattern of a subalpine forest-alpine pasture ecotone in the Central Pyrenees, that includes altitudinal timberline and treeline, and it is dominated by Pinus uncinata Ram. A rectangular (30 x 140 m) plot was located crossing the ecotone with its longest side parallel to the slope. We measured for each P. uncinata individual inside the plot: location (coordinates x, y), and structure (e. g. height) and growth form variables (number and type —living or dead, vertical or ...

Pattern self-repetition of fingerprints, lip prints, and palatal rugae among three generations of family: A forensic approach to identify family hierarchy.

Science.gov (United States)

Mala, Sankeerti; Rathod, Vanita; Pundir, Siddharth; Dixit, Sudhanshu

2017-01-01

The unique pattern and structural diversity of fingerprints, lip prints, palatal rugae, and their occurrence in different patterns among individuals make it questionable whether they are completely unique even in a family hierarchy? Do they have any repetition of the patterns among the generations? Or is this a mere chaos theory? The present study aims to assess the pattern self-repetition of fingerprints, lip prints, and palatal rugae among three generations of ten different families. The present study was conducted at Rungta College of Dental Science and Research, Bhilai, India. Participants birth by origin of Chhattisgarh were only included in the study. Thirty participants from three consecutive generations of ten different families were briefed about the purpose of the study, and their fingerprints, lip prints, and palatal rugae impression were recorded and analyzed for the pattern of self-repetition. Multiple comparisons among the generations and one-way analysis of variance test were performed using SPSS 20 trial version. Among the pattern of primary palatal rugae, 10% showed repetition in all the three generations. Thirty percent showed repetition of the pattern of thumb fingerprints in all the three generation. The pattern of lip prints in the middle 1/3 rd of lower lip, 20% showed repetition in alternative generations. The evaluations of fingerprints, lip prints, and palatal rugae showed fractal dimensions, occurring variations in dimensions according to the complexity of each structure. Even though a minute self-repetition in the patterns of lip, thumb, and palate among the three consequent generations in a family was observed considering the sample size, these results need to be confirmed in a larger sample, either to establish the role of chaos theory in forensic science or identifying a particular pattern of the individual in his family hierarchy.

Evaluation of second-generation central receiver technologies

International Nuclear Information System (INIS)

Kolb, G.L.; Chavez, J.M.; Klimas, P.; Meinecke, W.; Becker, M.; Kiera, M.

1993-01-01

This paper summarizes the results of a study performed by the US and Germany to assess the technical and economic potential of central receiver power plants and to identify the necessary research and development (R ampersand D) activities required to reach demonstration and commercialization. Second generation power plant designs, employing molten-salt and volumetric-air receivers, were assessed at the size of 30 and 100 MWe. The study developed a common guideline and used data from previous system tests and studies. The levelized-energy costs for the second generation plants were estimated and found to be competitive with costs from fossil-fueled power plants. Potential for further cost reductions exists if technical improvements can be introduced successfully in the long term. Additionally, the study presents results of plant reliability and uncertainty analyses. Mid- and long-term technical potentials are described, as well as recommendations for the R ampersand D activities needed to reach the goal of large-scale commercialization. The results of this study have already helped direct research in the US and Europe. For example, the favorable potential for these technologies has led to the Solar Two molten-salt project in the US and the TSA volumetric receiver test in Spain. In addition, early analysis conducted within this study indicated that an advanced thermal storage medium was necessary to achieve favorable economics for the air plant. This led to the design of the thermal storage system currently being tested in Spain. In summary, each of the investigated receiver technologies has mid- and long-term potential for improving plant performance and reducing capital and energy costs (resulting in less than 10 cts/kWh given excellent insolation conditions) in an environmentally safe way and largely independent of fossil-fuel prices

Protein recognition by a pattern-generating fluorescent molecular probe

Science.gov (United States)

Pode, Zohar; Peri-Naor, Ronny; Georgeson, Joseph M.; Ilani, Tal; Kiss, Vladimir; Unger, Tamar; Markus, Barak; Barr, Haim M.; Motiei, Leila; Margulies, David

2017-12-01

Fluorescent molecular probes have become valuable tools in protein research; however, the current methods for using these probes are less suitable for analysing specific populations of proteins in their native environment. In this study, we address this gap by developing a unimolecular fluorescent probe that combines the properties of small-molecule-based probes and cross-reactive sensor arrays (the so-called chemical 'noses/tongues'). On the one hand, the probe can detect different proteins by generating unique identification (ID) patterns, akin to cross-reactive arrays. On the other hand, its unimolecular scaffold and selective binding enable this ID-generating probe to identify combinations of specific protein families within complex mixtures and to discriminate among isoforms in living cells, where macroscopic arrays cannot access. The ability to recycle the molecular device and use it to track several binding interactions simultaneously further demonstrates how this approach could expand the fluorescent toolbox currently used to detect and image proteins.

Fractal systems of central places based on intermittency of space-filling

International Nuclear Information System (INIS)

Chen Yanguang

2011-01-01

Highlights: → The idea of intermittency is introduced into central place model. → The revised central place model suggests incomplete space filling. → New central place fractals are presented for urban analysis. → The average nearest distance is proposed to estimate the fractal dimension. → The concept of distance-based space is replaced by that of dimension-based space. - Abstract: The central place models are fundamentally important in theoretical geography and city planning theory. The texture and structure of central place networks have been demonstrated to be self-similar in both theoretical and empirical studies. However, the underlying rationale of central place fractals in the real world has not yet been revealed so far. This paper is devoted to illustrating the mechanisms by which the fractal patterns can be generated from central place systems. The structural dimension of the traditional central place models is d = 2 indicating no intermittency in the spatial distribution of human settlements. This dimension value is inconsistent with empirical observations. Substituting the complete space filling with the incomplete space filling, we can obtain central place models with fractional dimension D < d = 2 indicative of spatial intermittency. Thus the conventional central place models are converted into fractal central place models. If we further integrate the chance factors into the improved central place fractals, the theory will be able to explain the real patterns of urban places very well. As empirical analyses, the US cities and towns are employed to verify the fractal-based models of central places.

Sequentially firing neurons confer flexible timing in neural pattern generators

International Nuclear Information System (INIS)

Urban, Alexander; Ermentrout, Bard

2011-01-01

Neuronal networks exhibit a variety of complex spatiotemporal patterns that include sequential activity, synchrony, and wavelike dynamics. Inhibition is the primary means through which such patterns are implemented. This behavior is dependent on both the intrinsic dynamics of the individual neurons as well as the connectivity patterns. Many neural circuits consist of networks of smaller subcircuits (motifs) that are coupled together to form the larger system. In this paper, we consider a particularly simple motif, comprising purely inhibitory interactions, which generates sequential periodic dynamics. We first describe the dynamics of the single motif both for general balanced coupling (all cells receive the same number and strength of inputs) and then for a specific class of balanced networks: circulant systems. We couple these motifs together to form larger networks. We use the theory of weak coupling to derive phase models which, themselves, have a certain structure and symmetry. We show that this structure endows the coupled system with the ability to produce arbitrary timing relationships between symmetrically coupled motifs and that the phase relationships are robust over a wide range of frequencies. The theory is applicable to many other systems in biology and physics.

Patterns of gene variation in central and marginal populations of Drosophila robusta.

Science.gov (United States)

Prakash, S

1973-10-01

The central and marginal populations of D. robusta differ greatly in the level of inversion polymorphism; the marginal populations are monomorphic or nearly so and the central populations are highly polymorphic. This paper presents the frequencies of alleles at forty gene loci in various populations of D. robusta, studied by electrophoresis of proteins and enzymes. Population samples were obtained from eight widely separated populations of D. robusta which included the central, the extreme marginal and the intervening populations between the center and the margins. We find that the proportion of polymorphic loci and average heterozygosity per individual is slightly higher in the marginal populations than the central populations. In D. robusta on an average, 39% of the loci are polymorphic and the average proportion of loci heterozygous per individual is 11%. A breakdown of loci in three categories, viz, hydrolytic enzymes and some other enzymes, larval proteins and glycolytic and Kreb's cycle enzymes, shows that in all populations the level of polymorphism is highest in the hydrolytic enzymes, intermediate in larval proteins and least in the glycolytic and Kreb's cycle enzymes. On the average, the proportion of loci heterozygous per individual for three groups of loci is: hydrolytic enzymes and others (.164), larval proteins (.115) and glycolytic and Kreb's cycle enzymes (.037). We also observe that in all populations the level of polymorphism on the X chromosome is far less than the expected 38%; in salivary gland cells the euchromatic length of the X chromosome is 38% of the entire genome. Lower levels of polymorphism for the X chromosome loci are explained due to low probability of balanced polymorphisms for the X-linked loci since the conditions for establishment of balanced polymorphism for X-linked loci are more restrictive than for the autosomal loci.-The polymorphic loci can be grouped according to pattern of allele frequencies in different populations as

Generational Patterns in Mexican Americans' Academic Performance in an Unwelcoming Political Context

Science.gov (United States)

Moosmann, Danyel A. V.; Roosa, Mark W.; Knight, George P.

2014-01-01

Research has shown that immigrant students often do better academically than their U.S.-born peers from the same ethnic group but it is unclear whether this pattern holds for Mexican Americans. We examined the academic performance of four generations of Mexican American students from fifth to 10th grade looking for generation differences and explanations for them. Using data from 749 families, we tested a model with fifth grade variables that differed by generation as potential mediators linking student generation to 10th grade academic performance. Results showed that immigrants were academically behind at fifth grade but caught up by seventh. Only economic hardship mediated the long term relationship between student generation and 10th grade academic performance; maternal educational expectations and child language hassles, English usage, discrimination, and mainstream values helped explained the early academic deficit of immigrant children. The results identified potential targets for interventions to improve Mexican American students' academic performance. PMID:24578588

Can a change in cropping patterns produce water savings and social gains: A case study from the Fergana Valley, Central Asia

Directory of Open Access Journals (Sweden)

Karimov Akmal Kh.

2018-06-01

Full Text Available The study examines possible water savings by replacing alfalfa with winter wheat in the Fergana Valley, located upstream of the Syrdarya River in Central Asia. Agricultural reforms since the 1990s have promoted this change in cropping patterns in the Central Asian states to enhance food security and social benefits. The water use of alfalfa, winter wheat/fallow, and winter wheat/green gram (double cropping systems is compared for high-deficit, low-deficit, and full irrigation scenarios using hydrological modeling with the HYDRUS-1D software package. Modeling results indicate that replacing alfalfa with winter wheat in the Fergana Valley released significant water resources, mainly by reducing productive crop transpiration when abandoning alfalfa in favor of alternative cropping systems. However, the winter wheat/fallow cropping system caused high evaporation losses from fallow land after harvesting of winter wheat. Double cropping (i.e., the cultivation of green gram as a short duration summer crop after winter wheat harvesting reduced evaporation losses, enhanced crop output and hence food security, while generating water savings that make more water available for other productive uses. Beyond water savings, this paper also discusses the economic and social gains that double cropping produces for the public within a broader developmental context.

Multiple Chaotic Central Pattern Generators with Learning for Legged Locomotion and Malfunction Compensation

DEFF Research Database (Denmark)

Ren, Guanjiao; Chen, Weihai; Dasgupta, Sakyasingha

2015-01-01

on a simulated annealing algorithm. In a normal situation, the CPGs synchronize and their dynamics are identical. With leg malfunction or disability, the CPGs lose synchronization leading to independent dynamics. In this case, the learning mechanism is applied to automatically adjust the remaining legs...... in a physical simulation of a quadruped as well as a hexapod robot and finally in a real six-legged walking machine called AMOSII. The experimental results presented here reveal that using multiple CPGs with learning is an effective approach for adaptive locomotion generation where, for instance, different body...... chaotic CPG controller has difficulties dealing with leg malfunction. Specifically, in the scenarios presented here, its movement permanently deviates from the desired trajectory. To address this problem, we extend the single chaotic CPG to multiple CPGs with learning. The learning mechanism is based...

Statistical spatial properties of speckle patterns generated by multiple laser beams

International Nuclear Information System (INIS)

Le Cain, A.; Sajer, J. M.; Riazuelo, G.

2011-01-01

This paper investigates hot spot characteristics generated by the superposition of multiple laser beams. First, properties of speckle statistics are studied in the context of only one laser beam by computing the autocorrelation function. The case of multiple laser beams is then considered. In certain conditions, it is shown that speckles have an ellipsoidal shape. Analytical expressions of hot spot radii generated by multiple laser beams are derived and compared to numerical estimates made from the autocorrelation function. They are also compared to numerical simulations performed within the paraxial approximation. Excellent agreement is found for the speckle width as well as for the speckle length. Application to the speckle patterns generated in the Laser MegaJoule configuration in the zone where all the beams overlap is presented. Influence of polarization on the size of the speckles as well as on their abundance is studied.

Inductive class representation and its central role in pattern recognition

Energy Technology Data Exchange (ETDEWEB)

Goldfarb, L. [Univ. of New Brunswick, Fredericton, New Brunswick (Canada)

1996-12-31

The definition of inductive learning (IL) based on the new concept of inductive class representation (ICR) is given. The ICR, in addition to the ability to recognize a noise-corrupted object from the class, must also provide the means to generate every element in the resulting approximation of the class, i.e., the emphasis is on the generative capability of the ICR. Thus, the IL problem absorbs the main difficulties associated with a satisfactory formulation of the pattern recognition problem. This formulation of the IL problem appeared gradually as a result of the development of a fundamentally new formal model of IL--evolving transformation system (ETS) model. The model with striking clarity suggests that IL is the basic process which produces all the necessary {open_quotes}structures{close_quotes} for the recognition process, which is built directly on top of it. Based on the training set, the IL process, constructs optimal discriminatory (symbolic) weighted {open_quotes}features{close_quotes} which induce the corresponding optimal (symbolic) distance measure. The distance measure is a generalization of the weighted Levenshtein, or edit, distance defined on strings over a finite alphabet. The ETS model has emerged as a result of an attempt to unify two basic, but inadequate, approaches to pattern recognition: the classical vector space based and the syntactic approaches. ETS also elucidates with remarkable clarity the nature of the interrelationships between the corresponding symbolic and numeric mechanisms, in which the symbolic mechanisms play a more fundamental part. The model, in fact, suggests the first formal definition of the symbolic mathematical structure and also suggests a fundamentally different, more satisfactory, way of introducing the concept of fuzziness. The importance of the ICR concept to semiotics and semantics should become apparent as soon as one fully realizes that it represents the class and specifies the semantics of the class.

CENTRAL ENGINE MEMORY OF GAMMA-RAY BURSTS AND SOFT GAMMA-RAY REPEATERS

International Nuclear Information System (INIS)

Zhang, Bin-Bin; Castro-Tirado, Alberto J.; Zhang, Bing

2016-01-01

Gamma-ray bursts (GRBs) are bursts of γ-rays generated from relativistic jets launched from catastrophic events such as massive star core collapse or binary compact star coalescence. Previous studies suggested that GRB emission is erratic, with no noticeable memory in the central engine. Here we report a discovery that similar light curve patterns exist within individual bursts for at least some GRBs. Applying the Dynamic Time Warping method, we show that similarity of light curve patterns between pulses of a single burst or between the light curves of a GRB and its X-ray flare can be identified. This suggests that the central engine of at least some GRBs carries “memory” of its activities. We also show that the same technique can identify memory-like emission episodes in the flaring emission in soft gamma-ray repeaters (SGRs), which are believed to be Galactic, highly magnetized neutron stars named magnetars. Such a phenomenon challenges the standard black hole central engine models for GRBs, and suggest a common physical mechanism behind GRBs and SGRs, which points toward a magnetar central engine of GRBs

Generation, language, body mass index, and activity patterns in Hispanic children.

Science.gov (United States)

Taverno, Sharon E; Rollins, Brandi Y; Francis, Lori A

2010-02-01

The acculturation hypothesis proposes an overall disadvantage in health outcomes for Hispanic immigrants with more time spent living in the U.S., but little is known about how generational status and language may influence Hispanic children's relative weight and activity patterns. To investigate associations among generation and language with relative weight (BMI z-scores), physical activity, screen time, and participation in extracurricular activities (i.e., sports, clubs) in a U.S.-based, nationally representative sample of Hispanic children. Participants included 2012 Hispanic children aged 6-11 years from the cross-sectional 2003 National Survey of Children's Health. Children were grouped according to generational status (first, second, or third), and the primary language spoken in the home (English versus non-English). Primary analyses included adjusted logistic and multinomial logistic regression to examine the relationships among variables; all analyses were conducted between 2008 and 2009. Compared to third-generation, English speakers, first- and second-generation, non-English speakers were more than two times more likely to be obese. Moreover, first-generation, non-English speakers were half as likely to engage in regular physical activity and sports. Both first- and second-generation, non-English speakers were less likely to participate in clubs compared to second- and third-generation, English speakers. Overall, non-English-speaking groups reported less screen time compared to third-generation, English speakers. The hypothesis that Hispanics lose their health protection with more time spent in the U.S. was not supported in this sample of Hispanic children. Copyright 2010 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Central European projects could alter oil movement patterns

International Nuclear Information System (INIS)

Deffarges, E.H.; Howard, D.J.; Treat, J.E.

1991-01-01

This paper reports that several oil transportation projects are set to transform the flows of oil in Central Europe, with potentially important implications for crude oil and product prices in the region. These projects are spurred by the desires of the newly opened economies of Central Europe to diversify their sources of oil supplies away from the U.S.S.R. and by expectations of economic growth in this region. Today, Central European countries (Poland, Czechoslovakia, Hungary, Yugoslavia, Romania, and Bulgaria) rely heavily on Soviet crude supplies. Of the 1.7 million b/d of crude oil consumed by these six countries, about 55% is imported from the U.S.S.R. This is down significantly from the more than 75% import dependence in the mid-1980s. This dependency on U.S.S.R. crude - for countries that either have a history of indigenous production (Romania) or access to Middle East or North African supplies (Yugoslavia) - testifies to more than 40 years of centrally planned economics in which Moscow provided the energy and raw materials and Central European countries delivered finished goods. Since the end of World War II, the pipeline flow of crude oil and products from Western to Central Europe has been almost nonexistent. In fact, the Western European crude and product pipeline network itself is a rather poorly integrated system, with only limited interconnections between northern and southern networks and no real competition across the major flow routes

Recovery of rhythmic activity in a central pattern generator: analysis of the role of neuromodulator and activity-dependent mechanisms.

Science.gov (United States)

Zhang, Yili; Golowasch, Jorge

2011-11-01

The pyloric network of decapods crustaceans can undergo dramatic rhythmic activity changes. Under normal conditions the network generates low frequency rhythmic activity that depends obligatorily on the presence of neuromodulatory input from the central nervous system. When this input is removed (decentralization) the rhythmic activity ceases. In the continued absence of this input, periodic activity resumes after a few hours in the form of episodic bursting across the entire network that later turns into stable rhythmic activity that is nearly indistinguishable from control (recovery). It has been proposed that an activity-dependent modification of ionic conductance levels in the pyloric pacemaker neuron drives the process of recovery of activity. Previous modeling attempts have captured some aspects of the temporal changes observed experimentally, but key features could not be reproduced. Here we examined a model in which slow activity-dependent regulation of ionic conductances and slower neuromodulator-dependent regulation of intracellular Ca(2+) concentration reproduce all the temporal features of this recovery. Key aspects of these two regulatory mechanisms are their independence and their different kinetics. We also examined the role of variability (noise) in the activity-dependent regulation pathway and observe that it can help to reduce unrealistic constraints that were otherwise required on the neuromodulator-dependent pathway. We conclude that small variations in intracellular Ca(2+) concentration, a Ca(2+) uptake regulation mechanism that is directly targeted by neuromodulator-activated signaling pathways, and variability in the Ca(2+) concentration sensing signaling pathway can account for the observed changes in neuronal activity. Our conclusions are all amenable to experimental analysis.

Flat Supercontinuum Generation within the Telecommunication Wave Bands in a Photonic Crystal Fiber with Central Holes

International Nuclear Information System (INIS)

Han Ying; Hou Lan-Tian; Zhou Gui-Yao; Xia Chang-Ming; Wang Wei; Wang Chao; Hou Zhi-Yun; Yuan Jin-Hui

2012-01-01

Flat supercontinuum in the telecommunication wave bands of E+S+C is generated by coupling a train of femtosecond pulses generated by a mode-locked Ti:sapphire laser into the fundamental mode of a photonic crystal fiber with central holes fabricated in our lab. The pulse experiences the anomalous dispersion regime, and the soliton dynamic effect plays an important role in supercontinuum generation. The output spectrum in the wavelength range of 1360–1565 nm does not include significant ripples due to higher pump peak power, and the normalized intensity shows less fluctuation. (fundamental areas of phenomenology(including applications))

Endogenous rhythm and pattern-generating circuit interactions in cockroach motor centres

Directory of Open Access Journals (Sweden)

Izhak David

2016-09-01

Full Text Available Cockroaches are rapid and stable runners whose gaits emerge from the intricate, and not fully resolved, interplay between endogenous oscillatory pattern-generating networks and sensory feedback that shapes their rhythmic output. Here we studied the endogenous motor output of a brainless, deafferented preparation. We monitored the pilocarpine-induced rhythmic activity of levator and depressor motor neurons in the mesothoracic and metathoracic segments in order to reveal the oscillatory networks’ architecture and interactions. Data analyses included phase relations, latencies between and overlaps of rhythmic bursts, spike frequencies, and the dependence of these parameters on cycle frequency. We found that, overall, ipsilateral connections are stronger than contralateral ones. Our findings revealed asymmetries in connectivity among the different ganglia, in which meta-to-mesothoracic ascending coupling is stronger than meso-to-metathoracic descending coupling. Within-ganglion coupling between the metathoracic hemiganglia is stronger than that in the mesothoracic ganglion. We also report differences in the role and mode of operation of homologue network units (manifested by levator and depressor nerve activity. Many observed characteristics are similar to those exhibited by intact animals, suggesting a dominant role for feedforward control in cockroach locomotion. Based on these data we posit a connectivity scheme among components of the locomotion pattern generating system.

Commercialization of new energy technologies. Appendix A. Case study 1: central station electric power generation technologies

International Nuclear Information System (INIS)

1976-06-01

The results of a survey on Technologies for Central Power Generation are presented. The central power generation technologies selected for consideration were: fusion; breeder reactors; solar electric (thermal); geothermal; and magnetohydrodynamics. The responses of industry executives who make key investment decisions concerning new energy technologies and who to identify the problems faced in the development and commercialization of new energy systems are presented. Evaluation of these responses led to the following recommendations: increase industry input into the R, D and D planning process; establish and advocate priorities for new technologies based on detailed analysis of a technology's value in terms of overall national goals; create a mechanism for a joint ERDA/industry appraisal of priorities and programs; increase level of federal funding or subsidy of new technology demonstrations; and focus the activities of the national laboratories on basic research and very early product development; and emphasize industry involvement in systems development

Evolving cellular automata for diversity generation and pattern recognition: deterministic versus random strategy

International Nuclear Information System (INIS)

De Menezes, Marcio Argollo; Brigatti, Edgardo; Schwämmle, Veit

2013-01-01

Microbiological systems evolve to fulfil their tasks with maximal efficiency. The immune system is a remarkable example, where the distinction between self and non-self is made by means of molecular interaction between self-proteins and antigens, triggering affinity-dependent systemic actions. Specificity of this binding and the infinitude of potential antigenic patterns call for novel mechanisms to generate antibody diversity. Inspired by this problem, we develop a genetic algorithm where agents evolve their strings in the presence of random antigenic strings and reproduce with affinity-dependent rates. We ask what is the best strategy to generate diversity if agents can rearrange their strings a finite number of times. We find that endowing each agent with an inheritable cellular automaton rule for performing rearrangements makes the system more efficient in pattern-matching than if transformations are totally random. In the former implementation, the population evolves to a stationary state where agents with different automata rules coexist. (paper)

Variable resolution pattern generation for the Associative Memory of the ATLAS FTK project

CERN Document Server

Annovi, A; The ATLAS collaboration; Faulkner, G; Giannetti, P; Jiang, Z; Luongo, C; Pandini, C; Shochet, M; Tompkins, L; Volpi, G

2013-01-01

The Associative Memory (AM) chip is special device that allows to find coincidence patterns, or just patterns, between the incoming data in up to 8 parallel streams. The latest AM chip has been designed to receive silicon clusters generated in 8 layers of the ATLAS silicon detector sensor, to perform parallel track pattern matching at high rate and it will be the core of the FTK project. Data going through each of the busses are compared with a bank of patterns and AM chip looks for matches in each line, like commercial content addressable memory (CAM). The high density of hits expected in the ATLAS inner detector from 2015 put a challenge in the capability of the AM chip in rejecting random coincidences, requiring either an extremely high number of high precision patterns, with increasing costs and complexity of the system, or more flexible solutions. For this reason in the most recent prototype of the AM chip ternary cells have been added in the logic, allowing “don’t care” (DC) bits in the match. Hav...

Color pattern analysis of nymphalid butterfly wings: revision of the nymphalid groundplan.

Science.gov (United States)

Otaki, Joji M

2012-09-01

To better understand the developmental mechanisms of color pattern variation in butterfly wings, it is important to construct an accurate representation of pattern elements, known as the "nymphalid groundplan". However, some aspects of the current groundplan remain elusive. Here, I examined wing-wide elemental patterns of various nymphalid butterflies and confirmed that wing-wide color patterns are composed of the border, central, and basal symmetry systems. The central and basal symmetry systems can express circular patterns resembling eyespots, indicating that these systems have developmental mechanisms similar to those of the border symmetry system. The wing root band commonly occurs as a distinct symmetry system independent from the basal symmetry system. In addition, the marginal and submarginal bands are likely generated as a single system, referred to as the "marginal band system". Background spaces between two symmetry systems are sometimes light in coloration and can produce white bands, contributing significantly to color pattern diversity. When an element is enlarged with a pale central area, a visually similar (yet developmentally distinct) white band is produced. Based on the symmetric relationships of elements, I propose that both the central and border symmetry systems are comprised of "core elements" (the discal spot and the border ocelli, respectively) and a pair of "paracore elements" (the distal and proximal bands and the parafocal elements, respectively). Both core and paracore elements can be doubled, or outlined. Developmentally, this system configuration is consistent with the induction model, but not with the concentration gradient model for positional information.

Deposition, characterization, patterning and mechanistic study of inorganic resists for next-generation nanolithography

Science.gov (United States)

Luo, Feixiang

The semiconductor industry has witnessed a continuous decrease in the size of logic, memory and other computer chip components since its birth over half a century ago. The shrinking (scaling) of components has to a large extent been enabled by the development of micro- and now nano-lithographic techniques. This thesis focuses on one central component of lithography, the resist, which is essentially a thin film that when appropriately exposed enables a pattern to be printed onto a surface. Smaller features require an ever more precisely focused photon, electron or ion beam with which to expose the resist. The likely next generation source of radiation that will enable sub-20nm features to be written will employ extreme ultraviolet radiation (EUV), 92eV (13.5nm). The work discussed here involves a novel class of inorganic resists (including a solution processed Hf-based resist called HafSOx), as the organic resists that have dominated the microlithography industry for the past few decades have approached fundamental scaling limits. In order to maintain the high throughput required by high volume semiconductor manufacturing, metal oxide resists have been proposed and developed to meet the resolution and sensitivity in EUV lithography. One can think of our resists as the nano-lithographic analog to the silver halide film that dominated the photographic print industry for a century. In this thesis, we mainly describe our work on HafSOx, a "first generation" metal oxide EUV resist system. HafSOx thin films can be deposited by spin-coating a mixed solution of HfOCl2, H2O 2, and H2SO4. Various materials characterization techniques have been employed to achieve a comprehensive understanding of film composition and structure at both surface and bulk level, as well as a mechanistic understanding of the film radiation chemistry. Taking advantage of the high energy x-rays used in the XPS experiment, we developed an experiment to dynamically monitor the photochemistry within the

Ranging and grouping patterns of a western lowland gorilla group at Bai Hokou, Central African Republic.

Science.gov (United States)

Remis, M J

1997-01-01

The ranging and grouping patterns of a gorilla group were studied during 27 months from 1990-1992 at the Bai Hokou study site, Central African Republic. The study group ranged far daily (average = 2.3 km/day) and had a large home range (22.9 km2), relative to mountain gorillas, and ranging patterns differed between years. During 1990-1992, the bimale study group foraged less cohesively and had more flexible grouping patterns than mountain gorillas. The study group sometimes split into two distinct foraging subgroups, each led by a silverback, and these subgroups occasionally slept apart (mean = 950 m apart). Lowland gorillas rely on many of the same fruit resources as sympatric chimpanzees, and under certain demographic situations gorillas, like sympatric chimpanzees, may adapt their foraging group size to reduce intragroup feeding competition. However, the fiber content of the lowland gorilla diet likely relaxes constraints on foraging party size and facilitates group cohesion relative to chimpanzees.

The generation and distribution of central bank seigniorage in the Czech Republic, Hungary and Poland

Directory of Open Access Journals (Sweden)

Eduard Hochreiter

2002-12-01

Full Text Available We measure the amount of central bank seigniorage generated in three economies in transition and inquire to what extent seigniorage ultimately accrues to the government. We relate our findings to the institutional environment of the three countries. We find that, in parallel to the process of disinflation, seigniorage has declined substantially in the 1990s in all three countries under consideration pointing to more monetary discipline and a strengthening of central bank independence. Only in Hungary seigniorage benefited the government to a significant amount. We interpret this as being the consequence of past policies, rather than an obstacle to further disinflation.

Spatial patterns in gravel habitats and communities in the central and eastern English Channel

Science.gov (United States)

Coggan, Roger; Barrio Froján, Christopher R. S.; Diesing, Markus; Aldridge, John

2012-10-01

The distribution of sediment type and benthic communities in the central and eastern English Channel is shown to be polarised around a distinctive local hydrodynamic feature. The seabed in the region includes an extensive area of gravel substrate which is both an important habitat for benthic marine fauna and a valuable source of material for the marine aggregate industry. Effective management of the area is predicated on an understanding of whether it represents a single homogeneous unit, or several different units that may need to be managed in different ways. The aim of this study was to provide information that would inform such management decisions. Spatial patterns in gravel habitats and communities were studied by investigating the physical environment through modelled and empirical data, and the distribution of infauna and epifauna along an east-west trending transect. A common spatial pattern was observed in both physical and biological parameters, but rather than indicating a simple longitudinal gradient, there was a distinct polarisation around a central feature, a bedload parting (BLP) zone situated between the Isle of Wight and Cotentin peninsula. Sediments and communities at the eastern and western ends of the transect were more similar to each other than to those in the middle. The strong hydrodynamic regime in the BLP area controls sediment distribution, transporting finer material, mainly sand, away from the mid transect area. The pattern in sand content of the substrate mirrors the magnitude of the potential bedload transport, which is complex in this region due to the interplay between the M2 and M4 tidal constituents and produced a series of erosional and depositional zones. The structure of benthic communities reflected the local substrate and hydrodynamic conditions, with sponges observed among the stable substrates and stronger currents that characterised the mid transect area, while infauna became more diverse towards the ends of the

Distributed generation and centralized power system in Thailand

DEFF Research Database (Denmark)

Sukkumnoed, Decharut

2004-01-01

The paper examines and discusses conflicts between the development of distributed power and centralized power system.......The paper examines and discusses conflicts between the development of distributed power and centralized power system....

Neural computational modeling reveals a major role of corticospinal gating of central oscillations in the generation of essential tremor

Directory of Open Access Journals (Sweden)

Hong-en Qu

2017-01-01

Full Text Available Essential tremor, also referred to as familial tremor, is an autosomal dominant genetic disease and the most common movement disorder. It typically involves a postural and motor tremor of the hands, head or other part of the body. Essential tremor is driven by a central oscillation signal in the brain. However, the corticospinal mechanisms involved in the generation of essential tremor are unclear. Therefore, in this study, we used a neural computational model that includes both monosynaptic and multisynaptic corticospinal pathways interacting with a propriospinal neuronal network. A virtual arm model is driven by the central oscillation signal to simulate tremor activity behavior. Cortical descending commands are classified as alpha or gamma through monosynaptic or multisynaptic corticospinal pathways, which converge respectively on alpha or gamma motoneurons in the spinal cord. Several scenarios are evaluated based on the central oscillation signal passing down to the spinal motoneurons via each descending pathway. The simulated behaviors are compared with clinical essential tremor characteristics to identify the corticospinal pathways responsible for transmitting the central oscillation signal. A propriospinal neuron with strong cortical inhibition performs a gating function in the generation of essential tremor. Our results indicate that the propriospinal neuronal network is essential for relaying the central oscillation signal and the production of essential tremor.

Neural computational modeling reveals a major role of corticospinal gating of central oscillations in the generation of essential tremor.

Science.gov (United States)

Qu, Hong-En; Niu, Chuanxin M; Li, Si; Hao, Man-Zhao; Hu, Zi-Xiang; Xie, Qing; Lan, Ning

2017-12-01

Essential tremor, also referred to as familial tremor, is an autosomal dominant genetic disease and the most common movement disorder. It typically involves a postural and motor tremor of the hands, head or other part of the body. Essential tremor is driven by a central oscillation signal in the brain. However, the corticospinal mechanisms involved in the generation of essential tremor are unclear. Therefore, in this study, we used a neural computational model that includes both monosynaptic and multisynaptic corticospinal pathways interacting with a propriospinal neuronal network. A virtual arm model is driven by the central oscillation signal to simulate tremor activity behavior. Cortical descending commands are classified as alpha or gamma through monosynaptic or multisynaptic corticospinal pathways, which converge respectively on alpha or gamma motoneurons in the spinal cord. Several scenarios are evaluated based on the central oscillation signal passing down to the spinal motoneurons via each descending pathway. The simulated behaviors are compared with clinical essential tremor characteristics to identify the corticospinal pathways responsible for transmitting the central oscillation signal. A propriospinal neuron with strong cortical inhibition performs a gating function in the generation of essential tremor. Our results indicate that the propriospinal neuronal network is essential for relaying the central oscillation signal and the production of essential tremor.

TermGenie - a web-application for pattern-based ontology class generation.

Science.gov (United States)

Dietze, Heiko; Berardini, Tanya Z; Foulger, Rebecca E; Hill, David P; Lomax, Jane; Osumi-Sutherland, David; Roncaglia, Paola; Mungall, Christopher J

2014-01-01

Biological ontologies are continually growing and improving from requests for new classes (terms) by biocurators. These ontology requests can frequently create bottlenecks in the biocuration process, as ontology developers struggle to keep up, while manually processing these requests and create classes. TermGenie allows biocurators to generate new classes based on formally specified design patterns or templates. The system is web-based and can be accessed by any authorized curator through a web browser. Automated rules and reasoning engines are used to ensure validity, uniqueness and relationship to pre-existing classes. In the last 4 years the Gene Ontology TermGenie generated 4715 new classes, about 51.4% of all new classes created. The immediate generation of permanent identifiers proved not to be an issue with only 70 (1.4%) obsoleted classes. TermGenie is a web-based class-generation system that complements traditional ontology development tools. All classes added through pre-defined templates are guaranteed to have OWL equivalence axioms that are used for automatic classification and in some cases inter-ontology linkage. At the same time, the system is simple and intuitive and can be used by most biocurators without extensive training.

Reflection Patterns Generated by Condensed-Phase Oblique Detonation Interaction with a Rigid Wall

Science.gov (United States)

Short, Mark; Chiquete, Carlos; Bdzil, John; Meyer, Chad

2017-11-01

We examine numerically the wave reflection patterns generated by a detonation in a condensed phase explosive inclined obliquely but traveling parallel to a rigid wall as a function of incident angle. The problem is motivated by the characterization of detonation-material confiner interactions. We compare the reflection patterns for two detonation models, one where the reaction zone is spatially distributed, and the other where the reaction is instantaneous (a Chapman-Jouguet detonation). For the Chapman-Jouguet model, we compare the results of the computations with an asymptotic study recently conducted by Bdzil and Short for small detonation incident angles. We show that the ability of a spatially distributed reaction energy release to turn flow streamlines has a significant impact on the nature of the observed reflection patterns. The computational approach uses a shock-fit methodology.

A Novel Biped Pattern Generator Based on Extended ZMP and Extended Cart-Table Model

Directory of Open Access Journals (Sweden)

Guangbin Sun

2015-07-01

Full Text Available This paper focuses on planning patterns for biped walking on complex terrains. Two problems are solved: ZMP (zero moment point cannot be used on uneven terrain, and the conventional cart-table model does not allow vertical CM (centre of mass motion. For the ZMP definition problem, we propose the extended ZMP (EZMP concept as an extension of ZMP to uneven terrains. It can be used to judge dynamic balance on universal terrains. We achieve a deeper insight into the connection and difference between ZMP and EZMP by adding different constraints. For the model problem, we extend the cart-table model by using a dynamic constraint instead of constant height constraint, which results in a mathematically symmetric set of three equations. In this way, the vertical motion is enabled and the resultant equations are still linear. Based on the extended ZMP concept and extended cart-table model, a biped pattern generator using triple preview controllers is constructed and implemented simultaneously to three dimensions. Using the proposed pattern generator, the Atlas robot is simulated. The simulation results show the robot can walk stably on rather complex terrains by accurately tracking extended ZMP.

New insights into sucking, swallowing and breathing central generators: A complexity analysis of rhythmic motor behaviors.

Science.gov (United States)

Samson, Nathalie; Praud, Jean-Paul; Quenet, Brigitte; Similowski, Thomas; Straus, Christian

2017-01-18

Sucking, swallowing and breathing are dynamic motor behaviors. Breathing displays features of chaos-like dynamics, in particular nonlinearity and complexity, which take their source in the automatic command of breathing. In contrast, buccal/gill ventilation in amphibians is one of the rare motor behaviors that do not display nonlinear complexity. This study aimed at assessing whether sucking and swallowing would also follow nonlinear complex dynamics in the newborn lamb. Breathing movements were recorded before, during and after bottle-feeding. Sucking pressure and the integrated EMG of the thyroartenoid muscle, as an index of swallowing, were recorded during bottle-feeding. Nonlinear complexity of the whole signals was assessed through the calculation of the noise limit value (NL). Breathing and swallowing always exhibited chaos-like dynamics. The NL of breathing did not change significantly before, during or after bottle-feeding. On the other hand, sucking inconsistently and significantly less frequently than breathing exhibited a chaos-like dynamics. Therefore, the central pattern generator (CPG) that drives sucking may be functionally different from the breathing CPG. Furthermore, the analogy between buccal/gill ventilation and sucking suggests that the latter may take its phylogenetic origin in the gill ventilation CPG of the common ancestor of extant amphibians and mammals. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Discriminative Chemical Patterns: Automatic and Interactive Design.

Science.gov (United States)

Bietz, Stefan; Schomburg, Karen T; Hilbig, Matthias; Rarey, Matthias

2015-08-24

The classification of molecules with respect to their inhibiting, activating, or toxicological potential constitutes a central aspect in the field of cheminformatics. Often, a discriminative feature is needed to distinguish two different molecule sets. Besides physicochemical properties, substructures and chemical patterns belong to the descriptors most frequently applied for this purpose. As a commonly used example of this descriptor class, SMARTS strings represent a powerful concept for the representation and processing of abstract chemical patterns. While their usage facilitates a convenient way to apply previously derived classification rules on new molecule sets, the manual generation of useful SMARTS patterns remains a complex and time-consuming process. Here, we introduce SMARTSminer, a new algorithm for the automatic derivation of discriminative SMARTS patterns from preclassified molecule sets. Based on a specially adapted subgraph mining algorithm, SMARTSminer identifies structural features that are frequent in only one of the given molecule classes. In comparison to elemental substructures, it also supports the consideration of general and specific SMARTS features. Furthermore, SMARTSminer is integrated into an interactive pattern editor named SMARTSeditor. This allows for an intuitive visualization on the basis of the SMARTSviewer concept as well as interactive adaption and further improvement of the generated patterns. Additionally, a new molecular matching feature provides an immediate feedback on a pattern's matching behavior across the molecule sets. We demonstrate the utility of the SMARTSminer functionality and its integration into the SMARTSeditor software in several different classification scenarios.

Morphogenesis of polycrystalline dendritic patterns from evaporation of a reactive nanofluid sessile drop

Science.gov (United States)

Wu, Hua; Briscoe, Wuge H.

2018-04-01

We report polycrystalline residual patterns with dendritic micromorphologies upon fast evaporation of a mixed-solvent sessile drop containing reactive ZnO nanoparticles. The molecular and particulate species generated in situ upon evaporative drying collude with and modify the Marangoni solvent flows and Bénard-Marangoni instabilities, as they undergo self-assembly and self-organization under conditions far from equilibrium, leading to the ultimate hierarchical central cellular patterns surrounded by a peripheral coffee ring upon drying.

Concept and analytical basis for revistas - A fast, flexible computer/graphic system for generating periodic satellite coverage patterns

Science.gov (United States)

King, J. C.

1976-01-01

The generation of satellite coverage patterns is facilitated by three basic strategies: use of a simplified physical model, permitting rapid closed-form calculation; separation of earth rotation and nodal precession from initial geometric analyses; and use of symmetries to construct traces of indefinite length by repetitive transposition of basic one-quadrant elements. The complete coverage patterns generated consist of a basic nadir trace plus a number of associated off-nadir traces, one for each sensor swath edge to be delineated. Each trace is generated by transposing one or two of the basic quadrant elements into a circle on a nonrotating earth model sphere, after which the circle is expanded into the actual 'helical' pattern by adding rotational displacements to the longitude coordinates. The procedure adapts to the important periodic coverage cases by direct insertion of the characteristic integers N and R (days and orbital revolutions, respectively, per coverage period).

Classification of rhythmic locomotor patterns in electromyographic signals using fuzzy sets

Directory of Open Access Journals (Sweden)

Thrasher Timothy A

2011-12-01

Full Text Available Abstract Background Locomotor control is accomplished by a complex integration of neural mechanisms including a central pattern generator, spinal reflexes and supraspinal control centres. Patterns of muscle activation during walking exhibit an underlying structure in which groups of muscles seem to activate in united bursts. Presented here is a statistical approach for analyzing Surface Electromyography (SEMG data with the goal of classifying rhythmic "burst" patterns that are consistent with a central pattern generator model of locomotor control. Methods A fuzzy model of rhythmic locomotor patterns was optimized and evaluated using SEMG data from a convenience sample of four able-bodied individuals. As well, two subjects with pathological gait participated: one with Parkinson's Disease, and one with incomplete spinal cord injury. Subjects walked overground and on a treadmill while SEMG was recorded from major muscles of the lower extremities. The model was fit to half of the recorded data using non-linear optimization and validated against the other half of the data. The coefficient of determination, R2, was used to interpret the model's goodness of fit. Results Using four fuzzy burst patterns, the model was able to explain approximately 70-83% of the variance in muscle activation during treadmill gait and 74% during overground gait. When five burst functions were used, one function was found to be redundant. The model explained 81-83% of the variance in the Parkinsonian gait, and only 46-59% of the variance in spinal cord injured gait. Conclusions The analytical approach proposed in this article is a novel way to interpret multichannel SEMG signals by reducing the data into basic rhythmic patterns. This can help us better understand the role of rhythmic patterns in locomotor control.

Effects of rainfall patterns and land cover on the subsurface flow generation of sloping Ferralsols in southern China.

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Jian Duan

Full Text Available Rainfall patterns and land cover are two important factors that affect the runoff generation process. To determine the surface and subsurface flows associated with different rainfall patterns on sloping Ferralsols under different land cover types, observational data related to surface and subsurface flows from 5 m × 15 m plots were collected from 2010 to 2012. The experiment was conducted to assess three land cover types (grass, litter cover and bare land in the Jiangxi Provincial Soil and Water Conservation Ecological Park. During the study period, 114 natural rainfall events produced subsurface flow and were divided into four groups using k-means clustering according to rainfall duration, rainfall depth and maximum 30-min rainfall intensity. The results showed that the total runoff and surface flow values were highest for bare land under all four rainfall patterns and lowest for the covered plots. However, covered plots generated higher subsurface flow values than bare land. Moreover, the surface and subsurface flows associated with the three land cover types differed significantly under different rainfall patterns. Rainfall patterns with low intensities and long durations created more subsurface flow in the grass and litter cover types, whereas rainfall patterns with high intensities and short durations resulted in greater surface flow over bare land. Rainfall pattern I had the highest surface and subsurface flow values for the grass cover and litter cover types. The highest surface flow value and lowest subsurface flow value for bare land occurred under rainfall pattern IV. Rainfall pattern II generated the highest subsurface flow value for bare land. Therefore, grass or litter cover are able to convert more surface flow into subsurface flow under different rainfall patterns. The rainfall patterns studied had greater effects on subsurface flow than on total runoff and surface flow for covered surfaces, as well as a greater effect on surface

Ontorat: automatic generation of new ontology terms, annotations, and axioms based on ontology design patterns.

Science.gov (United States)

Xiang, Zuoshuang; Zheng, Jie; Lin, Yu; He, Yongqun

2015-01-01

It is time-consuming to build an ontology with many terms and axioms. Thus it is desired to automate the process of ontology development. Ontology Design Patterns (ODPs) provide a reusable solution to solve a recurrent modeling problem in the context of ontology engineering. Because ontology terms often follow specific ODPs, the Ontology for Biomedical Investigations (OBI) developers proposed a Quick Term Templates (QTTs) process targeted at generating new ontology classes following the same pattern, using term templates in a spreadsheet format. Inspired by the ODPs and QTTs, the Ontorat web application is developed to automatically generate new ontology terms, annotations of terms, and logical axioms based on a specific ODP(s). The inputs of an Ontorat execution include axiom expression settings, an input data file, ID generation settings, and a target ontology (optional). The axiom expression settings can be saved as a predesigned Ontorat setting format text file for reuse. The input data file is generated based on a template file created by a specific ODP (text or Excel format). Ontorat is an efficient tool for ontology expansion. Different use cases are described. For example, Ontorat was applied to automatically generate over 1,000 Japan RIKEN cell line cell terms with both logical axioms and rich annotation axioms in the Cell Line Ontology (CLO). Approximately 800 licensed animal vaccines were represented and annotated in the Vaccine Ontology (VO) by Ontorat. The OBI team used Ontorat to add assay and device terms required by ENCODE project. Ontorat was also used to add missing annotations to all existing Biobank specific terms in the Biobank Ontology. A collection of ODPs and templates with examples are provided on the Ontorat website and can be reused to facilitate ontology development. With ever increasing ontology development and applications, Ontorat provides a timely platform for generating and annotating a large number of ontology terms by following

Holocene re-colonisation, central-marginal distribution and habitat specialisation shape population genetic patterns within an Atlantic European grass species.

Science.gov (United States)

Harter, D E V; Jentsch, A; Durka, W

2015-05-01

Corynephorus canescens (L.) P.Beauv. is an outbreeding, short-lived and wind-dispersed grass species, highly specialised on scattered and disturbance-dependent habitats of open sandy sites. Its distribution ranges from the Iberian Peninsula over Atlantic regions of Western and Central Europe, but excludes the two other classical European glacial refuge regions on the Apennine and Balkan Peninsulas. To investigate genetic patterns of this uncommon combination of ecological and biogeographic species characteristics, we analysed AFLP variation among 49 populations throughout the European distribution range, expecting (i) patterns of SW European glacial refugia and post-glacial expansion to the NE; (ii) decreasing genetic diversity from central to marginal populations; and (iii) interacting effects of high gene flow and disturbance-driven genetic drift. Decreasing genetic diversity from SW to NE and distinct gene pool clustering imply refugia on the Iberian Peninsula and in western France, from where range expansion originated towards the NE. High genetic diversity within and moderate genetic differentiation among populations, and a significant pattern of isolation-by-distance indicate a gene flow drift equilibrium within C. canescens, probably due to its restriction to scattered and dynamic habitats and limited dispersal distances. These features, as well as the re-colonisation history, were found to affect genetic diversity gradients from central to marginal populations. Our study emphasises the need for including the specific ecology into analyses of species (re-)colonisation histories and range centre-margin analyses. To account for discontinuous distributions, new indices of marginality were tested for their suitability in studies of centre-periphery gradients. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

A Global Online Handwriting Recognition Approach Based on Frequent Patterns

Directory of Open Access Journals (Sweden)

C. Gmati

2018-06-01

Full Text Available In this article, the handwriting signals are represented based on geometric and spatio-temporal characteristics to increase the feature vectors relevance of each object. The main goal was to extract features in the form of a numeric vector based on the extraction of frequent patterns. We used two types of frequent motifs (closed frequent patterns and maximal frequent patterns that can represent handwritten characters pertinently. These common features patterns are generated from a raw data transformation method to achieve high relevance. A database of words consisting of two different letters was created. The proposed application gives promising results and highlights the advantages that frequent pattern extraction algorithms can achieve, as well as the central role played by the “minimum threshold” parameter in the overall description of the characters.

Antibiotic-Impregnated Central Venous Catheters Do Not Change Antibiotic Resistance Patterns.

Science.gov (United States)

Turnbull, Isaiah R; Buckman, Sara A; Horn, Christopher B; Bochicchio, Grant V; Mazuski, John E

2018-01-01

Antibiotic-impregnated central venous catheters (CVCs) decrease the incidence of infection in high-risk patients. However, use of these catheters carries the hypothetical risk of inducing antibiotic resistance. We hypothesized that routine use of minocycline and rifampin-impregnated catheters (MR-CVC) in a single intensive care unit (ICU) would change the resistance profile for Staphylococcus aureus. We reviewed antibiotic susceptibilities of S. aureus isolates obtained from blood cultures in a large urban teaching hospital from 2002-2015. Resistance patterns were compared before and after implementation of MR-CVC use in the surgical ICU (SICU) in August 2006. We also compared resistance patterns of S. aureus obtained in other ICUs and in non-ICU patients, in whom MR-CVCs were not used. Data for rifampin, oxacillin, and clindamycin were available for 9,703 cultures; tetracycline resistance data were available for 4,627 cultures. After implementation of MR-CVC use in the SICU, rifampin resistance remained unchanged, with rates the same as in other ICU and non-ICU populations (3%). After six years of use of MR-CVCs in the SICU, the rate of tetracycline resistance was unchanged in all facilities (1%-3%). The use of MR-CVCs was not associated with any change in S. aureus oxacillin-resistance rates in the SICU (66% vs. 60%). However, there was a significant decrease in S. aureus clindamycin resistance (59% vs. 34%; p resistance of S. aureus isolates to rifampin or tetracyclines.

Generation of crystal-structure transverse patterns via a self-frequency-doubling laser.

Science.gov (United States)

Yu, Haohai; Zhang, Huaijin; Wang, Yicheng; Wang, Zhengping; Wang, Jiyang; Petrov, V

2013-01-01

Two-dimensional (2D) visible crystal-structure patterns analogous to the quantum harmonic oscillator (QHO) have been experimentally observed in the near- and far-fields of a self-frequency-doubling (SFD) microchip laser. Different with the fundamental modes, the localization of the SFD light is changed with the propagation. Calculation based on Hermite-Gaussian (HG) functions and second harmonic generation theory reproduces well the patterns both in the near- and far-field which correspond to the intensity distribution in coordinate and momentum spaces, respectively. Considering the analogy of wave functions of the transverse HG mode and 2D harmonic oscillator, we propose that the simple monolithic SFD lasers can be used for developing of new materials and devices and testing 2D quantum mechanical theories.

Socio-Economic Factors Affecting Home Internet Usage Patterns in Central Queensland

Directory of Open Access Journals (Sweden)

Wal J. Taylor

2003-01-01

Full Text Available Governments and other policy makers are concerned with the gap in home Internet usage between people from metropolitan and rural areas. A survey conducted in Central Queensland, Australia examined differences in home Internet usage patterns between young and old, male and female, people in urban and rural areas, married and unmarried, well-educated and less educated, rich and poor, and employed and unemployed and found significant differences. These results highlight areas for further research and provide a basis for government agencies and industries to consider these associations in future policy formulation for regional development using ICT. The research suggested that further research should be conducted to monitor consuming behaviors of the youngest age group in Internet use for entertainment and information search in order to detect possible Internet overuse or addiction. In addition, further research should be conducted to find out what people search for on the Internet, and if for employment opportunities, financial incentives are suggested for the unemployed people.

Spatio-Temporal Patterns of the 2010–2015 Extreme Hydrological Drought across the Central Andes, Argentina

Directory of Open Access Journals (Sweden)

Juan Antonio Rivera

2017-08-01

Full Text Available During the period 2010–2015, the semi-arid Central Andes in Argentina (CAA experienced one of the most severe and long-lasting hydrological droughts on record. Since the snowmelt is the most important source of water, the reduced snowfall over the mountains propagated the drought signal through the streamflows in the adjacent foothills east of the Andes ranges. Motivated by the widespread impacts on the socio-economic activities in the region, this study aims to characterize the recent hydrological drought in terms of streamflow deficits. Based on streamflow data from 20 basins, we used the standardized streamflow index (SSI to characterize hydrological droughts during the period 1971–2016. We found that the regional extent of the 2010–2015 hydrological drought was limited to the basins located north of 38° S, with mean duration of 67 months and maximum drought severity exhibiting a heterogeneous pattern in terms of spatial distribution and time of occurrence. The drought event reached extreme conditions in 14 of the 15 basins in the CAA, being record-breaking drought in six of the basins. This condition was likely driven by a cooling in the tropical Pacific Ocean resembling La Niña conditions, which generated a decrease in snowfall over the Andes due to suppressed frontal activity.

Drosophila type II neuroblast lineages keep Prospero levels low to generate large clones that contribute to the adult brain central complex

Directory of Open Access Journals (Sweden)

Drummond Michael L

2010-10-01

Full Text Available Abstract Tissue homeostasis depends on the ability of stem cells to properly regulate self-renewal versus differentiation. Drosophila neural stem cells (neuroblasts are a model system to study self-renewal and differentiation. Recent work has identified two types of larval neuroblasts that have different self-renewal/differentiation properties. Type I neuroblasts bud off a series of small basal daughter cells (ganglion mother cells that each generate two neurons. Type II neuroblasts bud off small basal daughter cells called intermediate progenitors (INPs, with each INP generating 6 to 12 neurons. Type I neuroblasts and INPs have nuclear Asense and cytoplasmic Prospero, whereas type II neuroblasts lack both these transcription factors. Here we test whether Prospero distinguishes type I/II neuroblast identity or proliferation profile, using several newly characterized Gal4 lines. We misexpress prospero using the 19H09-Gal4 line (expressed in type II neuroblasts but no adjacent type I neuroblasts or 9D11-Gal4 line (expressed in INPs but not type II neuroblasts. We find that differential prospero expression does not distinguish type I and type II neuroblast identities, but Prospero regulates proliferation in both type I and type II neuroblast lineages. In addition, we use 9D11 lineage tracing to show that type II lineages generate both small-field and large-field neurons within the adult central complex, a brain region required for locomotion, flight, and visual pattern memory.

Effect of gum hardness on chewing pattern.

Science.gov (United States)

Plesh, O; Bishop, B; McCall, W

1986-06-01

Chewing rhythms are set by a putative central pattern generator whose output is influenced by sensory feedback. In this study we assessed how an altered feedback imposed by changing the hardness of a gum bolus modifies the timing of chewing, the maximal gape, and the activity in the masseter muscle on the chewing side. Ten adult subjects with no orofacial dysfunction chewed a standard piece of soft or hard gum for at least 3 min in random order. Vertical jaw movements were recorded with a kinesiograph and activity of the masseter muscle was recorded and integrated from surface EMG electrodes. The subjects sat in a dental chair and viewed a video lecture to distract their attention from chewing; they were instructed to chew on the right molars. Cycle-by-cycle analysis showed that 9 of the 10 subjects chewed the hard gum more slowly than the soft with no significant change in gape. The increases in cycle duration were due to changes in the duration of the opening and occlusal phases. The duration of closing was not significantly changed even though the duration and level of masseter activity were both significantly increased. We conclude that gum hardness by altering proprioceptive feedback modifies the output of the masticatory central pattern generator in such a way that the temporal aspects of chewing and the output of the masseteric motor pool are affected.

Age-specific mortality patterns in Central Mozambique during and after the end of the Civil War

Directory of Open Access Journals (Sweden)

Pearson R John C

2011-05-01

Full Text Available Abstract Background In recent years, vigorous debate has developed concerning how conflicts contribute to the spread of infectious diseases, and in particular, the role of post-conflict situations in the epidemiology of HIV/AIDS. This study details the age-specific mortality patterns among the population in the central provincial capital of Beira, Mozambique, during and after the Mozambican civil war which ended in 1992. Methods Data was collected from the death register at Beira's Central Hospital between 1985 and 2003 and descriptively analyzed. Results The data show two distinct periods: before and after the peace agreements in 1992. Before 1992 (during the civil war, the main impact of mortality was on children below 5 years of age, including still births, accounting for 58% of all deaths. After the war ended in 1992, the pattern shifted dramatically and rapidly to the 15-49 year old age group which accounted for 49% of all deaths by 2003. Conclusions As under-5 mortality rates were decreasing at the end of the conflict, rates for 24-49 year old adults began to dramatically increase due to AIDS. This study demonstrates that strategies can be implemented during conflicts to decrease mortality rates in one vulnerable population but post-conflict dynamics can bring together other factors which contribute to the rapid spread of other infectious diseases in other vulnerable populations.

Age-specific mortality patterns in Central Mozambique during and after the end of the Civil War.

Science.gov (United States)

Noden, Bruce H; Pearson, R John C; Gomes, Aurelio

2011-05-26

In recent years, vigorous debate has developed concerning how conflicts contribute to the spread of infectious diseases, and in particular, the role of post-conflict situations in the epidemiology of HIV/AIDS. This study details the age-specific mortality patterns among the population in the central provincial capital of Beira, Mozambique, during and after the Mozambican civil war which ended in 1992. Data was collected from the death register at Beira's Central Hospital between 1985 and 2003 and descriptively analyzed. The data show two distinct periods: before and after the peace agreements in 1992. Before 1992 (during the civil war), the main impact of mortality was on children below 5 years of age, including still births, accounting for 58% of all deaths. After the war ended in 1992, the pattern shifted dramatically and rapidly to the 15-49 year old age group which accounted for 49% of all deaths by 2003. As under-5 mortality rates were decreasing at the end of the conflict, rates for 24-49 year old adults began to dramatically increase due to AIDS. This study demonstrates that strategies can be implemented during conflicts to decrease mortality rates in one vulnerable population but post-conflict dynamics can bring together other factors which contribute to the rapid spread of other infectious diseases in other vulnerable populations.

Elevational pattern of bird species richness and its causes along a central Himalaya gradient, China.

Science.gov (United States)

Pan, Xinyuan; Ding, Zhifeng; Hu, Yiming; Liang, Jianchao; Wu, Yongjie; Si, Xingfeng; Guo, Mingfang; Hu, Huijian; Jin, Kun

2016-01-01

This study examines the relative importance of six variables: area, the mid-domain effect, temperature, precipitation, productivity, and habitat heterogeneity on elevational patterns of species richness for breeding birds along a central Himalaya gradient in the Gyirong Valley, the longest of five canyons in the Mount Qomolangma National Nature Reserve. We conducted field surveys in each of twelve elevational bands of 300 m between 1,800 and 5,400 m asl four times throughout the entire wet season. A total of 169 breeding bird species were recorded and most of the species (74%) were small-ranged. The species richness patterns of overall, large-ranged and small-ranged birds were all hump-shaped, but with peaks at different elevations. Large-ranged species and small-ranged species contributed equally to the overall richness pattern. Based on the bivariate and multiple regression analyses, area and precipitation were not crucial factors in determining the species richness along this gradient. The mid-domain effect played an important role in shaping the richness pattern of large-ranged species. Temperature was negatively correlated with overall and large-ranged species but positively correlated with small-ranged species. Productivity was a strong explanatory factor among all the bird groups, and habitat heterogeneity played an important role in shaping the elevational richness patterns of overall and small-ranged species. Our results highlight the need to conserve primary forest and intact habitat in this area. Furthermore, we need to increase conservation efforts in this montane biodiversity hotspot in light of increasing anthropogenic activities and land use pressure.

Effects of dietary pattern and education on glycemic control in patients with type 2 diabetes mellitus at Dr. Sardjito Central General Hospital, Yogyakarta.

Science.gov (United States)

Sinorita, Hemi; Saádah; Jazakillah, Setyowati

2008-04-01

to recognize the effect of education and diet on glycemic control in patients with type 2 diabetes mellitus at Dr. Sardjito Central General Hospital, Jogjakarta. a cross-sectional study was conducted in 88 patients with type 2 DM who had routine visit to the outpatient clinic in Endocrinology Division of Dr. Sardjito Central General Hospital, Jogjakarta. As inclusion criteria, patients who had routine visit in 3 month continuously with fasting plasma glucose (GDN) 126 mg/dl as poor glycemic control group. Data were recorded which included age, sex, period of DM, daily diet pattern, and education received. we found that glycemic control was not affected by sex (p=0.52) and age (p=0.38), but it was affected by period of DM (p=0.02). Glycemic control in the present study was affected by dietary pattern (p=0.01), but not by education (p=1.00). the present study has found significant correlation between regulation of dietary pattern and glycemic control (p=0.01).

Impact of cercal air currents on singing motor pattern generation in the cricket (Gryllus bimaculatus DeGeer)

Science.gov (United States)

2015-01-01

The cercal system of crickets detects low-frequency air currents produced by approaching predators and self-generated air currents during singing, which may provide sensory feedback to the singing motor network. We analyzed the effect of cercal stimulation on singing motor pattern generation to reveal the response of a singing interneuron to predator-like signals and to elucidate the possible role of self-generated air currents during singing. In fictive singing males, we recorded an interneuron of the singing network while applying air currents to the cerci; additionally, we analyzed the effect of abolishing the cercal system in freely singing males. In fictively singing crickets, the effect of short air stimuli is either to terminate prematurely or to lengthen the interchirp interval, depending on their phase in the chirp cycle. Within our stimulation paradigm, air stimuli of different velocities and durations always elicited an inhibitory postsynaptic potential in the singing interneuron. Current injection in the singing interneuron elicited singing motor activity, even during the air current-evoked inhibitory input from the cercal pathway. The disruptive effects of air stimuli on the fictive singing pattern and the inhibitory response of the singing interneuron point toward the cercal system being involved in initiating avoidance responses in singing crickets, according to the established role of cerci in a predator escape pathway. After abolishing the activity of the cercal system, the timing of natural singing activity was not significantly altered. Our study provides no evidence that self-generated cercal sensory activity has a feedback function for singing motor pattern generation. PMID:26334014

Pattern and predictors of neurological morbidities among childhood cerebral malaria survivors in central Sudan.

Science.gov (United States)

Mergani, Adil; Khamis, Ammar H; Fatih Hashim, E L; Gumma, Mohamed; Awadelseed, Bella; Elwali, Nasr Eldin M A; Haboor, Ali Babikir

2015-09-01

Cerebral malaria is considered a leading cause of neuro-disability in sub-Saharan Africa among children and about 25% of survivors have long-term neurological and cognitive deficits or epilepsy. Their development was reported to be associated with protracted seizures, deep and prolonged coma. The study was aimed to determine the discharge pattern and to identify potential and informative predictors of neurological sequelae at discharge, complicating childhood cerebral malaria in central Sudan. A cross-sectional prospective study was carried out during malaria transmission seasons from 2000 to 2004 in Wad Medani, Sinnar and Singa hospitals, central Sudan. Children suspected of having cerebral malaria were examined and diagnosed by a Pediatrician for clinical, laboratory findings and any neurological complications. Univariate and multiple regression model analysis were performed to evaluate the association of clinical and laboratory findings with occurrence of neurological complications using the SPSS. Out of 940 examined children, only 409 were diagnosed with cerebral malaria with a mean age of 6.1 ± 3.3 yr. The mortality rate associated with the study was 14.2% (58) and 18.2% (64) of survivors (351) had neurological sequelae. Abnormal posture, either decerebration or decortication, focal convulsion and coma duration of >48 h were significant predictors for surviving from cerebral malaria with a neurological sequelae in children from central Sudan by Univariate analysis. Multiple logistic regression model fitting these variables, revealed 39.6% sensitivity for prediction of childhood cerebral malaria survivors with neurological sequelae (R² = 0.396; p=0.001). Neurological sequelae are common due to childhood cerebral malaria in central Sudan. Their prediction at admission, clinical presentation and laboratory findings may guide clinical intervention and proper management that may decrease morbidity and improve CM consequences.

Automatic generation of aesthetic patterns on fractal tilings by means of dynamical systems

International Nuclear Information System (INIS)

Chung, K.W.; Ma, H.M.

2005-01-01

A fractal tiling or f-tiling is a tiling which possesses self-similarity and the boundary of which is a fractal. In this paper, we investigate the classification of fractal tilings with kite-shaped and dart-shaped prototiles from which three new f-tilings are found. Invariant mappings are constructed for the creation of aesthetic patterns on such tilings. A modified convergence time scheme is described, which reflects the rate of convergence of various orbits and at the same time, enhances the artistic appeal of a generated image. A scheme based on the frequency of visit at a pixel is used to generate chaotic attractors

Distribution patterns and enrichment of lead, zinc and copper in surface sediments of the central Portuguese shelf and upper slope

NARCIS (Netherlands)

Jesus, C.C.; de Stigter, H.; Miranda, P.; Oliveira, A.; Rocha, F.

2013-01-01

Geographic patterns of Cu, Pb and Zn enrichment on the Lisbon-Setúbal-Sines continental shelf and upper slope (central Portuguese margin) were studied in this paper to gain insight into current pathways of trace metal dispersal. Our study is based on the analysis of elemental concentrations and

Patterns of Abundance and Host Specificity of Bat Ectoparasites in the Central Balkans.

Science.gov (United States)

Burazerovic, J; Orlova, M; Obradovic, M; Cirovic, D; Tomanovic, S

2018-01-10

Bats are hosts to a number of ectoparasites-acarines (ticks, chiggers, other mites), bat flies, and fleas. Bat ectoparasites might have significant ecological and public health importance as they may be potential vectors of zoonotic agents. It is important to identify their distribution, diversity, and host-parasite associations. Bat ectoparasites in the central Balkans have been largely understudied. The present research was conducted in 45 localities at the territory of Bosnia and Herzegovina, former Yugoslav Republic of Macedonia, Montenegro, and Serbia. In total, 1,143 individuals of 18 species of bats have been examined for the presence and abundance of ectoparasite species during 3 yr of research. In total, 21 ectoparasite species have been identified: three species of ticks, seven species of mites (including one species of chigger), eight species of bat flies, and three species of fleas. In total, 80 host-parasite associations have been identified. The largest number of ectoparasites parasitized primarily only one host species. The highest total number of hosts was identified for ectoparasite species Ixodes vespertilionis Koch, Nycteribia schmidlii Schiner, and Spinturnix myoti Kolenati. The spinturnicid mite Spinturnix psi Kolenati was the most abundant ectoparasite species and together with Penicilidia dufouri Westwood the most widely distributed species of bat ectoparasite, being present at 21 localities in the central Balkans. The presented data include the first systematic records of patterns of prevalence, mean intensity, mean abundance, and host specificity for bat ectoparasites in the central Balkans. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Patterns of seabird and marine mammal carcass deposition along the central California coast, 1980-1986

Science.gov (United States)

Bodkin, James L.; Jameson, Ronald J.

1991-01-01

At monthly intervals from February 1980 through December 1986, a 14.5-km section of central California coastline was systematically surveyed for beach-cast carcasses of marine birds and mammals. Five hundred and fifty-four bird carcasses and 194 marine mammal carcasses were found. Common murres, western grebes, and Brandt's cormorants composed 45% of the bird total. California sea lions, sea otters, and harbor seals composed 90% of the mammal total. Several factors appeared to affect patterns of carcass deposition. The El Niño – Southern Oscillation (ENSO) of 1982–1983 was the dominant influence in terms of interannual variation in carcass deposition. During this ENSO, 56% of the seabirds and 48% of the marine mammals washed ashore. Patterns of intra-annual variation were species specific and were related to animal migration patterns, reproduction, and seasonal changes in weather. Nearshore currents and winds influenced the general area of carcass deposition, while beach substrate type and local patterns of sand deposition influenced the location of carcass deposition on a smaller spatial scale. Weekly surveys along a 1.1-km section of coastline indicated that 62% of bird carcasses and 41% of mammal carcasses remained on the beach less than 9 days. Cause of death was determined for only 8% of the carcasses. Oiling was the most common indication of cause of death in birds (6%). Neonates composed 8% of all mammal carcasses.

Generating power stations and optimization energetic of processes; Centrales generadoras y optimacion energetica de procesos

Energy Technology Data Exchange (ETDEWEB)

Gutierrez Ramirez, Ranulfo; Fernandez Montiel, Manuel Francisco [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

1999-07-01

Some recent experiences of the Management of Thermal Processes of the Instituto de Investigaciones Electricas (IIE) related to the works on generating power stations of electricity, plants of cogeneration and energy saving are presented. [Spanish] Se presentan algunas experiencias recientes de la Gerencia de Procesos Termicos del Instituto de Investigaciones Electricas (IIE) relacionadas con los trabajos sobre centrales generadoras de electricidad, plantas de cogeneracion y ahorro de energia.

Fast Lagrangian relaxation for constrained generation scheduling in a centralized electricity market

International Nuclear Information System (INIS)

Ongsakul, Weerakorn; Petcharaks, Nit

2008-01-01

This paper proposes a fast Lagrangian relaxation (FLR) for constrained generation scheduling (CGS) problem in a centralized electricity market. FLR minimizes the consumer payment rather than the total supply cost subject to the power balance, spinning reserve, transmission line, and generator operating constraints. FLR algorithm is improved by new initialization of Lagrangian multipliers and adaptive adjustment of Lagrangian multipliers. The adaptive subgradient method using high quality initial feasible multipliers requires much less number of iterations to converge, leading to a faster computational time. If congestion exists, the alleviating congestion index is proposed for congestion management. Finally, the unit decommitment is performed to prevent excessive spinning reserve. The FLR for CGS is tested on the 4 unit and the IEEE 24 bus reliability test systems. The proposed uniform electricity price results in a lower consumer payment than system marginal price based on uniformly fixed cost amortized allocation, non-uniform price, and electricity price incorporating side payment, leading to a lower electricity price. In addition, observations on objective functions, pricing scheme comparison and interpretation of Lagrangian multipliers are provided. (author)

Contrasting pattern of hydrological changes during the past two millennia from central and northern India: Regional climate difference or anthropogenic impact?

Science.gov (United States)

Mishra, Praveen K.; Prasad, Sushma; Marwan, Norbert; Anoop, A.; Krishnan, R.; Gaye, Birgit; Basavaiah, N.; Stebich, Martina; Menzel, Philip; Riedel, Nils

2018-02-01

High resolution reconstructions of the India Summer Monsoon (ISM) are essential to identify regionally different patterns of climate change and refine predictive models. We find opposing trends of hydrological proxies between northern (Sahiya cave stalagmite) and central India (Lonar Lake) between 100 and 1300 CE with the strongest anti-correlation between 810 and 1300 CE. The apparently contradictory data raise the question if these are related to widely different regional precipitation patterns or reflect human influence in/around the Lonar Lake. By comparing multiproxy data with historical records, we demonstrate that only the organic proxies in the Lonar Lake show evidence of anthropogenic impact. However, evaporite data (mineralogy and δ18O) are indicative of precipitation/evaporation (P/E) into the Lonar Lake. Back-trajectories of air-mass circulation over northern and central India show that the relative contribution of the Bay of Bengal (BoB) branch of the ISM is crucial for determining the δ18O of carbonate proxies only in north India, whereas central India is affected significantly by the Arabian Sea (AS) branch of the ISM. We conclude that the δ18O of evaporative carbonates in the Lonar Lake reflects P/E and, in the interval under consideration, is not influenced by source water changes. The opposing trend between central and northern India can be explained by (i) persistent multidecadal droughts over central India between 810 and 1300 CE that provided an effective mechanism for strengthening sub-tropical westerly winds resulting in enhancement of wintertime (non-monsoonal) rainfall over northern parts of the Indian subcontinent, and/or (ii) increased moisture influx to northern India from the depleted BoB source waters.

A Model of Electrically Stimulated Auditory Nerve Fiber Responses with Peripheral and Central Sites of Spike Generation

DEFF Research Database (Denmark)

Joshi, Suyash Narendra; Dau, Torsten; Epp, Bastian

2017-01-01

. A single ANF is modeled as a network of two exponential integrateand-fire point-neuron models, referred to as peripheral and central axons of the ANF. The peripheral axon is excited by the cathodic charge, inhibited by the anodic charge, and exhibits longer spike latencies than the central axon......A computational model of cat auditory nerve fiber (ANF) responses to electrical stimulation is presented. The model assumes that (1) there exist at least two sites of spike generation along the ANF and (2) both an anodic (positive) and a cathodic (negative) charge in isolation can evoke a spike......; the central axon is excited by the anodic charge, inhibited by the cathodic charge, and exhibits shorter spike latencies than the peripheral axon. The model also includes subthreshold and suprathreshold adaptive feedback loops which continuously modify the membrane potential and can account for effects...

Gondwana subduction-modified mantle domain prevents magmatic seafloor generation in the Central Indian Ridge

Science.gov (United States)

Morishita, T.; Nakamura, K.; Senda, R.; Suzuki, K.; Kumagai, H.; Sato, H.; Sato, T.; Shibuya, T.; Minoguchi, K.; Okino, K.

2013-12-01

The creation of oceanic crust at mid-ocean ridges is essential to understanding the genesis of oceanic plate and the evolution of the Earth. Detailed bathymetric measurements coupled with dense sample recovery at mid-ocean ridge revealed a wide range of variations in the ridge and seafloor morphologies, which cannot be simply explained by a spreading rate, but also by ridge geometry, mantle compositions and thermal structure (Dick et al., 2003 Nature; Cannat et al. 2006 Geology). It is now widely accepted that very limited magmatic activity with tectonic stretching generates oceanic core complex and/or smooth seafloor surface in the slow to ultraslow-spreading ridges, where serpentinized peridotite and gabbros are expected to be exposed associated with detachment faults (Cann et al., 1997 Nature; Cannat et al., 2006), although magmatism might be an essential role for the formation of oceanic core complexes (Buck et al., 2005 Nature; Tucholke et al 2008 JGR). A rising question is why magmatic activity is sometimes prevented during the oceanic plate formation. Ancient melting domain, that are too refractory to melt even in adiabatically upwelling to the shallow upper mantle, might cause the amagmatic spreading ridges (Harvey et al., 2006 EPSL, Liu et al.,2008 Nature). Its origin and effect on seafloor generations are, however, not well understood yet. We report an oceanic hill as an example of an ancient subduction-modified mantle domain, probably formed at continental margin of the Gondwanaland~Pangea supercontinent, existing beneath the Central Indian Ridge. This domain is the most likely to have prevented magmatic seafloor generation, resulting in creation of very deep oceanic valley and serpentine diaper (now the studied oceanic hill) at the present Central Indian ridge.

Simulation and spatiotemporal pattern of air temperature and precipitation in Eastern Central Asia using RegCM.

Science.gov (United States)

Meng, Xianyong; Long, Aihua; Wu, Yiping; Yin, Gang; Wang, Hao; Ji, Xiaonan

2018-02-26

Central Asia is a region that has a large land mass, yet meteorological stations in this area are relatively scarce. To address this data issues, in this study, we selected two reanalysis datasets (the ERA40 and NCEP/NCAR) and downscaled them to 40 × 40 km using RegCM. Then three gridded datasets (the CRU, APHRO, and WM) that were extrapolated from the observations of Central Asian meteorological stations to evaluate the performance of RegCM and analyze the spatiotemporal distribution of precipitation and air temperature. We found that since the 1960s, the air temperature in Xinjiang shows an increasing trend and the distribution of precipitation in the Tianshan area is quite complex. The precipitation is increasing in the south of the Tianshan Mountains (Southern Xinjiang, SX) and decreasing in the mountainous areas. The CRU and WM data indicate that precipitation in the north of the Tianshan Mountains (Northern Xinjiang, NX) is increasing, while the APHRO data show an opposite trend. The downscaled results from RegCM are generally consistent with the extrapolated gridded datasets in terms of the spatiotemporal patterns. We believe that our results can provide useful information in developing a regional climate model in Central Asia where meteorological stations are scarce.

Peri-Urban Matters. Changing Olive Growing Patterns in Central Italy

Directory of Open Access Journals (Sweden)

Anna Laura Palazzo

2017-04-01

Full Text Available For centuries, olive growing has played a major role in the central regions of Italy, with hectares of olive groves surrounding hill towns and hamlets as part of a strong deep-rooted farming tradition. With reference to Lazio and Abruzzo, this article makes use of historical documentation, geographical surveys and in-depth interviews with professionals and experts, in order to provide evidence of how olive growing, once of the mixed type, now with specialized cultivations, has somehow challenged the structural features of traditional landscapes. In some cases, this ancient farming tradition has been awarded the ‘Protected Designation of Origin Brand’ according to strict technical production policies. Besides intensive crops, today also practiced on flat ground, for some years now, olive trees have been cultivated by ‘hobby farmers’. This is frequent in fringe areas, threatened by urban sprawl, within small plots belonging to detached family homes conferring a sense of rural ‘revival’. Whether all these diverse settlement patterns are socially and economically sustainable is debatable. Definitely, such persistence in land use, which now and again can be read even as a material survival of certain tree specimens, allows for olive farming as an enduring cultural practice in the face of increasing urbanization.

Coherent Rabi oscillations in a molecular system and sub-diffraction-limited pattern generation

International Nuclear Information System (INIS)

Liao, Zeyang; Al-Amri, M; Zubairy, M Suhail

2015-01-01

The resolution of a photolithography and optical imaging system is restricted by the diffraction limit. Coherent Rabi oscillations have been shown to be able to overcome the diffraction limit in a simple two-level atomic system (Z Liao, M Al-amri, and M S Zubairy 2010 Phys. Rev. Lett. 105 183601). In this paper, we numerically calculate the wave packet dynamics of a molecular system interacting with an ultrashort laser pulse and show that coherent Rabi oscillations in a molecular system are also possible. Moreover, a sub-diffraction-limited pattern can be generated in this system by introducing spatially modulated Rabi oscillations. We also discuss several techniques to improve the visibility of the sub-diffraction-limited pattern. Our result may have important applications in super-resolution optical lithography and optical imaging. (paper)

Connecting the dots: Illusory pattern perception predicts belief in conspiracies and the supernatural.

Science.gov (United States)

van Prooijen, Jan-Willem; Douglas, Karen M; De Inocencio, Clara

2018-04-01

A common assumption is that belief in conspiracy theories and supernatural phenomena are grounded in illusory pattern perception. In the present research we systematically tested this assumption. Study 1 revealed that such irrational beliefs are related to perceiving patterns in randomly generated coin toss outcomes. In Study 2, pattern search instructions exerted an indirect effect on irrational beliefs through pattern perception. Study 3 revealed that perceiving patterns in chaotic but not in structured paintings predicted irrational beliefs. In Study 4, we found that agreement with texts supporting paranormal phenomena or conspiracy theories predicted pattern perception. In Study 5, we manipulated belief in a specific conspiracy theory. This manipulation influenced the extent to which people perceive patterns in world events, which in turn predicted unrelated irrational beliefs. We conclude that illusory pattern perception is a central cognitive mechanism accounting for conspiracy theories and supernatural beliefs.

Connecting the dots: Illusory pattern perception predicts belief in conspiracies and the supernatural

Science.gov (United States)

Douglas, Karen M.; De Inocencio, Clara

2017-01-01

Abstract A common assumption is that belief in conspiracy theories and supernatural phenomena are grounded in illusory pattern perception. In the present research we systematically tested this assumption. Study 1 revealed that such irrational beliefs are related to perceiving patterns in randomly generated coin toss outcomes. In Study 2, pattern search instructions exerted an indirect effect on irrational beliefs through pattern perception. Study 3 revealed that perceiving patterns in chaotic but not in structured paintings predicted irrational beliefs. In Study 4, we found that agreement with texts supporting paranormal phenomena or conspiracy theories predicted pattern perception. In Study 5, we manipulated belief in a specific conspiracy theory. This manipulation influenced the extent to which people perceive patterns in world events, which in turn predicted unrelated irrational beliefs. We conclude that illusory pattern perception is a central cognitive mechanism accounting for conspiracy theories and supernatural beliefs. PMID:29695889

Determination of activity by gamma spectrometry of radionuclides present in drums of residues generated in nuclear centrals; Determinacion de actividad por espectrometria gamma de radionucleidos presentes en tambores de residuos generados en centrales nucleares

Energy Technology Data Exchange (ETDEWEB)

Aguiar, J.C.; Fernandez, J. [Autoridad Regulatoria Nuclear, Av. Del Libertador 8250, Ciudad Autonoma de Buenos Aires (Argentina)]. e-mail: jaguiar@cae.arn.gov.ar

2006-07-01

The generation of radioactive residuals in nuclear centrals as CNA I (Atucha I Nuclear Central) and CNE (Embalse Nuclear Central) makes that the measurement of those radionuclides has been a previous stage to the waste management. A method used in those nuclear centrals it is the gamma spectrometry with HPGe detectors, previous to the immobilization of the residual in a cemented matrix, with this the contact with the external agents and its possible dispersion to the atmosphere in the short term is avoided. The ARN (Nuclear Regulatory Authority) of Argentina it carries out periodically intercomparisons and evaluations of the measurement and procedures systems used in the nuclear power stations for the correct measurement and determination of activity of radioactive residuals by gamma spectrometry. In this work an independent method of measurement is exposed to the nuclear power stations. To determine the activity of the residuals by gamma spectrometry deposited in drums, it is required of the precise knowledge of the efficiency curve for such geometry and matrix. Due to the RNA doesn't have a pattern of these characteristics, a mathematical model has been used to obtain this efficiency curve. For it, it is necessary to determine previously: 1) the geometric efficiency or solid angle sustained by the source-detector system (drum-detector) applying a mathematical model described in this work. 2) To estimate the auto-attenuation factor that present the photons in the cemented matrix, these calculations are carried out with a simple equation and its are verified with the Micro Shield 6.10 program. The container commonly used by these nuclear power stations its are drums for 220 liters constructed with SAE 1010 steel and with a thickness of 0.127 cm, with an approximate weight 7.73 Kg., internal diameter of 57.1 cm, and height: 87 cm. The results obtained until the moment register a discrepancy from 5 to 10% with relationship to the measurements carried out by the

SARAPAN—A Simulated-Annealing-Based Tool to Generate Random Patterned-Channel-Age in CANDU Fuel Management Analyses

Directory of Open Access Journals (Sweden)

Doddy Kastanya

2017-02-01

Full Text Available In any reactor physics analysis, the instantaneous power distribution in the core can be calculated when the actual bundle-wise burnup distribution is known. Considering the fact that CANDU (Canada Deuterium Uranium utilizes on-power refueling to compensate for the reduction of reactivity due to fuel burnup, in the CANDU fuel management analysis, snapshots of power and burnup distributions can be obtained by simulating and tracking the reactor operation over an extended period using various tools such as the *SIMULATE module of the Reactor Fueling Simulation Program (RFSP code. However, for some studies, such as an evaluation of a conceptual design of a next-generation CANDU reactor, the preferred approach to obtain a snapshot of the power distribution in the core is based on the patterned-channel-age model implemented in the *INSTANTAN module of the RFSP code. The objective of this approach is to obtain a representative snapshot of core conditions quickly. At present, such patterns could be generated by using a program called RANDIS, which is implemented within the *INSTANTAN module. In this work, we present an alternative approach to derive the patterned-channel-age model where a simulated-annealing-based algorithm is used to find such patterns, which produce reasonable power distributions.

SARAPAN-A simulated-annealing-based tool to generate random patterned-channel-age in CANDU fuel management analyses

Energy Technology Data Exchange (ETDEWEB)

Kastanya, Doddy [Safety and Licensing Department, Candesco Division of Kinectrics Inc., Toronto (Canada)

2017-02-15

In any reactor physics analysis, the instantaneous power distribution in the core can be calculated when the actual bundle-wise burnup distribution is known. Considering the fact that CANDU (Canada Deuterium Uranium) utilizes on-power refueling to compensate for the reduction of reactivity due to fuel burnup, in the CANDU fuel management analysis, snapshots of power and burnup distributions can be obtained by simulating and tracking the reactor operation over an extended period using various tools such as the *SIMULATE module of the Reactor Fueling Simulation Program (RFSP) code. However, for some studies, such as an evaluation of a conceptual design of a next-generation CANDU reactor, the preferred approach to obtain a snapshot of the power distribution in the core is based on the patterned-channel-age model implemented in the *INSTANTAN module of the RFSP code. The objective of this approach is to obtain a representative snapshot of core conditions quickly. At present, such patterns could be generated by using a program called RANDIS, which is implemented within the *INSTANTAN module. In this work, we present an alternative approach to derive the patterned-channel-age model where a simulated-annealing-based algorithm is used to find such patterns, which produce reasonable power distributions.

Wave of chaos in a diffusive system: Generating realistic patterns of patchiness in plankton-fish dynamics

International Nuclear Information System (INIS)

Upadhyay, Ranjit Kumar; Kumari, Nitu; Rai, Vikas

2009-01-01

We show that wave of chaos (WOC) can generate two-dimensional time-independent spatial patterns which can be a potential candidate for understanding planktonic patchiness observed in marine environments. These spatio-temporal patterns were obtained in computer simulations of a minimal model of phytoplankton-zooplankton dynamics driven by forces of diffusion. We also attempt to figure out the average lifetimes of these non-linear non-equilibrium patterns. These spatial patterns serve as a realistic model for patchiness found in aquatic systems (e.g., marine and oceanic). Additionally, spatio-temporal chaos produced by bi-directional WOCs is robust to changes in key parameters of the system; e.g., intra-specific competition among individuals of phytoplankton and the rate of fish predation. The ideas contained in the present paper may find applications in diverse fields of human endeavor.

Pattern of Maxillofacial fracture in Western and Central Nepal: An experience in 3 tertiary level health institutions

Directory of Open Access Journals (Sweden)

S Subedi

2015-06-01

Full Text Available BACKGROUND: There are only few studies regarding the pattern and causes of maxillofacial fractures till date in Nepal and no such study in western and central Nepalese population has been conducted. The purpose of this study, therefore, was to describe the causes and the pattern of maxillofacial fractures in western and central part of Nepal over the period of 5 years. MATERIAL AND METHODS A retrospective analysis of maxillofacial fractures was conducted on 328 patients who were treated in the department of maxillofacial surgery. Data was extracted and analyzed based on age, sex, cause of injury and anatomic location. RESULT Young males of 3rd decade of life most commonly sustained the maxillofacial trauma. The commonest site involved was the zygomatic complex (42% when only mid face fractures was considered and parasymphysis (32% when only mandible was considered.The most common cause of injuries was road traffic accidents (289 patients; 88.1% followed by interpersonal violence (25 patients; 7.6 % and falls accounting for 4.2% of the all injuries. CONCLUSION The findings of this study suggest the need for expansion of the motorway network, ensuring compliance of strict traffic rules and regulations, replacing old vehicles without safety measures and implement school education in alcohol abuse.DOI: http://dx.doi.org/10.3126/jcmsn.v10i3.12771 Journal of College of Medical Sciences-Nepal, 2014, Vol-10, No-3, 8-13

Engineering systems for the generation of patterned co-cultures for controlling cell-cell interactions.

Science.gov (United States)

Kaji, Hirokazu; Camci-Unal, Gulden; Langer, Robert; Khademhosseini, Ali

2011-03-01

Inside the body, cells lie in direct contact or in close proximity to other cell types in a tightly controlled architecture that often regulates the resulting tissue function. Therefore, tissue engineering constructs that aim to reproduce the architecture and the geometry of tissues will benefit from methods of controlling cell-cell interactions with microscale resolution. We discuss the use of microfabrication technologies for generating patterned co-cultures. In addition, we categorize patterned co-culture systems by cell type and discuss the implications of regulating cell-cell interactions in the resulting biological function of the tissues. Patterned co-cultures are a useful tool for fabricating tissue engineered constructs and for studying cell-cell interactions in vitro, because they can be used to control the degree of homotypic and heterotypic cell-cell contact. In addition, this approach can be manipulated to elucidate important factors involved in cell-matrix interactions. Patterned co-culture strategies hold significant potential to develop biomimetic structures for tissue engineering. It is expected that they would create opportunities to develop artificial tissues in the future. This article is part of a Special Issue entitled Nanotechnologies - Emerging Applications in Biomedicine. 2010 Elsevier B.V. All rights reserved.

Resolution Improvement and Pattern Generator Development for the Maskless Micro-Ion-Beam Reduction Lithography System

International Nuclear Information System (INIS)

Jiang, Ximan

2006-01-01

have been studied. The dependence of the throughput with the exposure field size and the speed of the mechanical stage has been investigated. In order to perform maskless lithography, different micro-fabricated pattern generators have been developed for the MMRL system. Ion beamlet switching has been successfully demonstrated on the MMRL system. A positive bias voltage around 10 volts is sufficient to switch off the ion current on the micro-fabricated pattern generators. Some unexpected problems, such as the high-energy secondary electron radiations, have been discovered during the experimental investigation. Thermal and structural analysis indicates that the aperture displacement error induced by thermal expansion can satisfy the 3(delta) CD requirement for lithography nodes down to 25 nm. The cross-talking effect near the surface and inside the apertures of the pattern generator has been simulated in a 3-D ray-tracing code. New pattern generator design has been proposed to reduce the cross-talking effect. In order to eliminate the surface charging effect caused by the secondary electrons, a new beam-switching scheme in which the switching electrodes are immersed in the plasma has been demonstrated on a mechanically fabricated pattern generator

Turbulence anisotropy and coherent structures in electromagnetically generated vortex patterns

International Nuclear Information System (INIS)

Kenjereš, S

2011-01-01

Numerical investigations addressing influence of the localised electromagnetic forcing on turbulent thermal convection of a weakly electrically conductive fluid in a wall-bounded rectangular enclosure are performed over a wide range of working parameters (10 4 ≤Ra≤5×10 5 , Pr = 7). An asymmetrical electromagnetic forcing (EMF) is applied originating from combined effects of the imposed magnetic fields (originating from an array of 5×7 permanent magnets with |b 0 | max = 1 T each, located beneath the lower thermally active wall) and electric fields (originating from two electrodes supplied with dc current of different intensities, 0≤I≤10 A). Subgrid turbulent stress is modelled by electromagnetically extended Smagorinsky model and subgrid turbulent heat flux is represented by a simple gradient diffusion hypothesis. Simulations revealed two interesting findings: the electromagnetic forcing generated significant overall heat transfer increase (more than 500% for lower values of Ra) compared to its neutral case, and, the turbulence anisotropy was reduced in the central part of the enclosure.

Research on trading patterns of large users' direct power purchase considering consumption of clean energy

Science.gov (United States)

Guojun, He; Lin, Guo; Zhicheng, Yu; Xiaojun, Zhu; Lei, Wang; Zhiqiang, Zhao

2017-03-01

In order to reduce the stochastic volatility of supply and demand, and maintain the electric power system's stability after large scale stochastic renewable energy sources connected to grid, the development and consumption should be promoted by marketing means. Bilateral contract transaction model of large users' direct power purchase conforms to the actual situation of our country. Trading pattern of large users' direct power purchase is analyzed in this paper, characteristics of each power generation are summed up, and centralized matching mode is mainly introduced. Through the establishment of power generation enterprises' priority evaluation index system and the analysis of power generation enterprises' priority based on fuzzy clustering, the sorting method of power generation enterprises' priority in trading patterns of large users' direct power purchase is put forward. Suggestions for trading mechanism of large users' direct power purchase are offered by this method, which is good for expand the promotion of large users' direct power purchase further.

Convergence of pattern generator outputs on a common mechanism of diaphragm motor unit recruitment.

Science.gov (United States)

Mantilla, Carlos B; Seven, Yasin B; Sieck, Gary C

2014-01-01

Motor units are the final element of neuromotor control. In manner analogous to the organization of neuromotor control in other skeletal muscles, diaphragm motor units comprise phrenic motoneurons located in the cervical spinal cord that innervate the diaphragm muscle, the main inspiratory muscle in mammals. Diaphragm motor units play a primary role in sustaining ventilation but are also active in other nonventilatory behaviors, including coughing, sneezing, vomiting, defecation, and parturition. Diaphragm muscle fibers comprise all fiber types. Thus, diaphragm motor units display substantial differences in contractile and fatigue properties, but importantly, properties of the motoneuron and muscle fibers within a motor unit are matched. As in other skeletal muscles, diaphragm motor units are recruited in order such that motor units that display greater fatigue resistance are recruited earlier and more often than more fatigable motor units. The properties of the motor unit population are critical determinants of the function of a skeletal muscle across the range of possible motor tasks. Accordingly, fatigue-resistant motor units are sufficient to generate the forces necessary for ventilatory behaviors, whereas more fatigable units are only activated during expulsive behaviors important for airway clearance. Neuromotor control of diaphragm motor units may reflect selective inputs from distinct pattern generators distributed according to the motor unit properties necessary to accomplish these different motor tasks. In contrast, widely distributed inputs to phrenic motoneurons from various pattern generators (e.g., for breathing, coughing, or vocalization) would dictate recruitment order based on intrinsic electrophysiological properties. © 2014 Elsevier B.V. All rights reserved.

Mechanisms of Left-Right Coordination in Mammalian Locomotor Pattern Generation Circuits: A Mathematical Modeling View

Science.gov (United States)

Talpalar, Adolfo E.; Rybak, Ilya A.

2015-01-01

The locomotor gait in limbed animals is defined by the left-right leg coordination and locomotor speed. Coordination between left and right neural activities in the spinal cord controlling left and right legs is provided by commissural interneurons (CINs). Several CIN types have been genetically identified, including the excitatory V3 and excitatory and inhibitory V0 types. Recent studies demonstrated that genetic elimination of all V0 CINs caused switching from a normal left-right alternating activity to a left-right synchronized “hopping” pattern. Furthermore, ablation of only the inhibitory V0 CINs (V0D subtype) resulted in a lack of left-right alternation at low locomotor frequencies and retaining this alternation at high frequencies, whereas selective ablation of the excitatory V0 neurons (V0V subtype) maintained the left–right alternation at low frequencies and switched to a hopping pattern at high frequencies. To analyze these findings, we developed a simplified mathematical model of neural circuits consisting of four pacemaker neurons representing left and right, flexor and extensor rhythm-generating centers interacting via commissural pathways representing V3, V0D, and V0V CINs. The locomotor frequency was controlled by a parameter defining the excitation of neurons and commissural pathways mimicking the effects of N-methyl-D-aspartate on locomotor frequency in isolated rodent spinal cord preparations. The model demonstrated a typical left-right alternating pattern under control conditions, switching to a hopping activity at any frequency after removing both V0 connections, a synchronized pattern at low frequencies with alternation at high frequencies after removing only V0D connections, and an alternating pattern at low frequencies with hopping at high frequencies after removing only V0V connections. We used bifurcation theory and fast-slow decomposition methods to analyze network behavior in the above regimes and transitions between them. The model

System-dependent regulations of colour-pattern development: a mutagenesis study of the pale grass blue butterfly

Science.gov (United States)

Iwata, Masaki; Hiyama, Atsuki; Otaki, Joji M.

2013-01-01

Developmental studies on wing colour patterns have been performed in nymphalid butterflies, but efficient genetic manipulations, including mutagenesis, have not been well established. Here, we have performed mutagenesis experiments in a lycaenid butterfly, the pale grass blue Zizeeria maha, to produce colour-pattern mutants. We fed the P-generation larvae an artificial diet containing the mutagen ethyl methane sulfonate (EMS), and the F1- and F2-generation adults showed various aberrant colour patterns: dorsoventral transformation, anterioposterior background colouration gap, weak contrast, disarrangement of spots, reduction of the size of spots, loss of spots, fusion of spots, and ectopic spots. Among them, the disarrangement, reduction, and loss of spots were likely produced by the coordinated changes of many spots of a single wing around the discal spot in a system-dependent manner, demonstrating the existence of the central symmetry system. The present study revealed multiple genetic regulations for system-dependent and wing-wide colour-pattern determination in lycaenid butterflies. PMID:23917124

Associations Between β-Amyloid Kinetics and the β-Amyloid Diurnal Pattern in the Central Nervous System.

Science.gov (United States)

Lucey, Brendan P; Mawuenyega, Kwasi G; Patterson, Bruce W; Elbert, Donald L; Ovod, Vitaliy; Kasten, Tom; Morris, John C; Bateman, Randall J

2017-02-01

Recent studies found that the concentration of amyloid-β (Aβ) fluctuates with the sleep-wake cycle. Although the amplitude of this day/night pattern attenuates with age and amyloid deposition, to our knowledge, the association of Aβ kinetics (ie, production, turnover, and clearance) with this oscillation has not been studied. To determine the association between Aβ kinetics, age, amyloid levels, and the Aβ day/night pattern in humans. We measured Aβ concentrations and kinetics in 77 adults aged 60 to 87 years with and without amyloid deposition by a novel precise mass spectrometry method at the Washington University School of Medicine in St Louis, Missouri. We compared findings of 2 orthogonal methods, enzyme-linked immunosorbent assay and mass spectrometry, to validate the day/night patterns and determine more precise estimates of the cosinor parameters. In vivo labeling of central nervous system proteins with stable isotopically labeled leucine was performed, and kinetics of Aβ40 and Aβ42 were measured. Serial cerebrospinal fluid collection via indwelling lumbar catheter over 36 to 48 hours before, during, and after in vivo labeling, with a 9-hour primed constant infusion of 13C6-leucine. The amplitude, linear increase, and other cosinor measures of each participant's serial cerebrospinal fluid Aβ concentrations and Aβ turnover rates. Of the 77 participants studied, 46 (59.7%) were men, and the mean (range) age was 72.6 (60.4-87.7) years. Day/night patterns in Aβ concentrations were more sharply defined by the precise mass spectrometry method than by enzyme-linked immunosorbent assay (mean difference of SD of residuals: Aβ40, -7.42 pM; P effects of age and amyloid on Aβ42 amplitude at least partially affect each other. Production and turnover rates suggest that day/night Aβ patterns are modulated by both production and clearance mechanisms active in sleep-wake cycles and that amyloid deposition may impair normal circadian patterns. These findings

Model Predictive Control-based gait pattern generation for wearable exoskeletons.

Science.gov (United States)

Wang, Letian; van Asseldonk, Edwin H F; van der Kooij, Herman

2011-01-01

This paper introduces a new method for controlling wearable exoskeletons that do not need predefined joint trajectories. Instead, it only needs basic gait descriptors such as step length, swing duration, and walking speed. End point Model Predictive Control (MPC) is used to generate the online joint trajectories based on these gait parameters. Real-time ability and control performance of the method during the swing phase of gait cycle is studied in this paper. Experiments are performed by helping a human subject swing his leg with different patterns in the LOPES gait trainer. Results show that the method is able to assist subjects to make steps with different step length and step duration without predefined joint trajectories and is fast enough for real-time implementation. Future study of the method will focus on controlling the exoskeletons in the entire gait cycle. © 2011 IEEE

Levels And Patterns Of Violence During The Transition Into The Middle Horizon On The Central Coast Of Peru

OpenAIRE

Vega, María del Carmen

2016-01-01

This article examines the patterns and prevalence of trauma in 256 Late Lima individuals. is assemblage of human remains comes from the sites of Huaca 20 and Copacabana and was compared to 45 Middle Lima individuals from thesite of Cerro Culebra, as well as 30 individuals from the Middle Horizon 2 and 4 (Miramar). Other investigators have proposed that social and political changes during the transition into the Middle Horizon on the Central Coast of Perumight have caused an increase in episod...

Postglacial recolonization in a cold climate specialist in western Europe: patterns of genetic diversity in the adder (Vipera berus) support the central-marginal hypothesis.

Science.gov (United States)

Ursenbacher, Sylvain; Guillon, Michaël; Cubizolle, Hervé; Dupoué, Andréaz; Blouin-Demers, Gabriel; Lourdais, Olivier

2015-07-01

Understanding the impact of postglacial recolonization on genetic diversity is essential in explaining current patterns of genetic variation. The central-marginal hypothesis (CMH) predicts a reduction in genetic diversity from the core of the distribution to peripheral populations, as well as reduced connectivity between peripheral populations. While the CMH has received considerable empirical support, its broad applicability is still debated and alternative hypotheses predict different spatial patterns of genetic diversity. Using microsatellite markers, we analysed the genetic diversity of the adder (Vipera berus) in western Europe to reconstruct postglacial recolonization. Approximate Bayesian Computation (ABC) analyses suggested a postglacial recolonization from two routes: a western route from the Atlantic Coast up to Belgium and a central route from the Massif Central to the Alps. This cold-adapted species likely used two isolated glacial refugia in southern France, in permafrost-free areas during the last glacial maximum. Adder populations further from putative glacial refugia had lower genetic diversity and reduced connectivity; therefore, our results support the predictions of the CMH. Our study also illustrates the utility of highly variable nuclear markers, such as microsatellites, and ABC to test competing recolonization hypotheses. © 2015 John Wiley & Sons Ltd.

Geometric origin of central charges

International Nuclear Information System (INIS)

Lukierski, J.; Rytel, L.

1981-05-01

The complete set of N(N-1) central charge generators for D=4 N-extended super Poincare algebra is obtained by suitable contraction of OSp (2N; 4) superalgebra. The superspace realizations of the spinorial generators with central charges are derived. The conjugate set of N(N-1) additional bosonic superspace coordinates is introduced in an unique and geometric way. (author)

Generation of heat on fuel rod in cosine pattern by using induction heating

International Nuclear Information System (INIS)

Keettikkal, Felix; Sajeesh, Divya; Rao, Poornima; Hande, Shashank; Dakave, Ganesh; Kute, Tushar; Mahajan, Akshay; Kulkarni, R.D.

2017-01-01

Fuel rods are used in a nuclear reactor for fission process. When these rods are cooled by water during the heat transfer, the temperature stress causes undesirable defects in the fuel rod. Studying these defects occurring in the fuel rod in the nuclear cluster during nuclear reaction is a difficult task because fission reaction makes it difficult to analyse the changes in the rod. Hence there is a need to use a replica of the rod with similar thermal stress to study and analyse the rod for the defects. Normally the heat generated on the fuel rod follows a cosine pattern which is an inherent characteristic inside a nuclear reactor. In view of this, in this paper induction heating method is used on a rod to create an exact replica of the cosine pattern of heat by varying the pitch of the coil. First, a MATLAB simulation is done using simulink. Then a prototype of the model has been developed comprising of carbon steel pipe, with length and outside diameter of 1 meter and 48.2 mm, respectively. Instead of using water as coolant, rod is simulated in air. Therefore, the heat generated is lost by normal convection and radiation. Non-nuclear testing can be a valuable tool in the development or in some kind of experiment using nuclear reactor. Induction heating becomes an alternative to classical heating technologies because of its advantages such as efficiency, quickness, safety, clean heating and accurate power control. (author)

Feedback of Erosional-Depositional Processes Generating Anabranching Patterns in a Mega-River the Case of the PARANÁ River, Argentina

Science.gov (United States)

Latrubesse, E. M.; Pereira, M.; Ramonell, C. G.; Szupiany, R. N.

2011-12-01

A new category of "very large" rivers was recently proposed and defined as mega-rivers, which are those rivers with a Qmean of more than ~17,000m3/s. This category includes the nine largest rivers on Earth and the Parana River is one of the selected members of that peculiar group. The planform adjustment of mega-rivers is a variety of anabranching patterns characterized by the existence of alluvial islands. The processes and mechanisms involved in the generation of the different anabranching styles, however, are not well understood. The Paraná channel pattern has been classified as a low to moderate anabranching, low sinuosity with tendency to braided and having a meandering thalweg. We analyzed a reach of the middle Paraná in Argentina applying a combined multitemporal, hydraulic, sedimentologic and geomorphologic approach. Multitemporal geomorphologic maps, sedimentary descriptions of bars, islands and banks, volumetric calculations using multitemporal bathymetric charts, measurements with ADCP and bathymetric surveys with echosound, sediment transport estimations and the hydrological analysis of available data from gauge stations were some of the tools used in our research. The evolution of the reach was studied from 1908 to present. The reach is subdivided in two sub-reaches (named Chapeton and Curtiembre) which are comprised between nodal points. Chapeton has been in a more mature quasi-equilibrium state through the XX Century but the main channel in Curtiembre evolved from a single pattern to anabranching pattern since 1950s. We conclude that the generation of the anabranching pattern in the studied reach depends of a combination of factors such as the architecture of the floodplain and islands, the main role played by the morphodynamics and shifting of the thalweg, the availability and path of sandy sediments bedforms architecture and the temporal variability of the effective discharge among other secondary factors. A feedback system coupling erosional

Habitat use and foraging patterns of molting male Long-tailed Ducks in lagoons of the central Beaufort Sea, Alaska

Science.gov (United States)

Flint, Paul L.; Reed, John; Deborah Lacroix,; Richard Lanctot,

2016-01-01

From mid-July through September, 10 000 to 30 000 Long-tailed Ducks (Clangula hyemalis) use the lagoon systems of the central Beaufort Sea for remigial molt. Little is known about their foraging behavior and patterns of habitat use during this flightless period. We used radio transmitters to track male Long-tailed Ducks through the molt period from 2000 to 2002 in three lagoons: one adjacent to industrial oil field development and activity and two in areas without industrial activity. We found that an index to time spent foraging generally increased through the molt period. Foraging, habitat use, and home range size showed similar patterns, but those patterns were highly variable among lagoons and across years. Even with continuous daylight during the study period, birds tended to use offshore areas during the day for feeding and roosted in protected nearshore waters at night. We suspect that variability in behaviors associated with foraging, habitat use, and home range size are likely influenced by availability of invertebrate prey. Proximity to oil field activity did not appear to affect foraging behaviors of molting Long-tailed Ducks.

Automatic test pattern generation for stuck-at and delay faults in combinational circuits

International Nuclear Information System (INIS)

Kim, Dae Sik

1998-02-01

The present studies are developed to propose the automatic test pattern generation (ATG) algorithms for combinational circuits. These ATG algorithms are realized in two ATG programs: One is the ATG program for stuck-at fault and the other one for delay faults. In order to accelerate the ATG process, these two ATG programs have a common feature (the search method based on the concept of the degree of freedom), whereas only ATG program for the delay fault utilizes the 19-valued logic, a type of composite valued logic. This difference between two ATG programs results from the difference of the target fault. Accelerating the ATG process is indispensable for improving the ATG algorithms. This acceleration is mainly achieved by reducing the number of the unnecessary backtrackings, making the earlier detection of the conflicts, and shortening the computation time between the implication. Because of this purpose, the developed ATG programs include the new search method based on the concept of the degree of freedom (DF). The DF concept, computed directly and easily from the system descriptions such as types of gates and their interconnections, is the criterion to decide which, among several alternate lines' logic values required along each path, promises to be the most effective in order to accelerate and improve the ATG process. This DF concept is utilized to develop and improve both of ATG programs for stuck-at and delay faults in combinational circuits. In addition to improving the ATG process, reducing number of test pattern is indispensable for testing the delay faults because the size of the delay faults grows rapidly as increasing the size of the circuit. In order to improve the compactness of the test set, 19-valued logic are derived. Unlike other TG logic systems, 19-valued logic is utilized to generate the robustly hazard-free test pattern. This is achieved by using the basic 5-valued logic, proposed in this work, where the transition with no hazard is

Central Asia in a Changing World: From a Peripheral Region to an Area of Policy Generation and Application. Actors, Policy and Security

Directory of Open Access Journals (Sweden)

Nora Sainz Gsell

2005-10-01

Full Text Available This work deals with Central Asia, beginning with an analysis of the characteristics of international insertion of the area as a whole and of the former Soviet republics that comprise it. In a general way, it aims to analyse the evolution of Central Asia from a peripheral region to an area that generates behaviours and receives the application of policies on the part ofinternational actors. In the first part of the study, it mentions a series of particularities of the republics that have determined the relationships in the region(the Central Asian order and those between the region and the outside world; it indicates geo-historical and economic-strategic aspects. In the second part, it examines the foreign policy of the republics in the post-Cold War era from the singularities of domestic policy. And, in the third part, it analyses, according to the aforementioned peculiarities, the policies that the area and each State has generated in international actors, both regional ones and global ones, and which have transformed the region from a peripheral one to a geopolitically emerging one.

larvalign: Aligning Gene Expression Patterns from the Larval Brain of Drosophila melanogaster.

Science.gov (United States)

Muenzing, Sascha E A; Strauch, Martin; Truman, James W; Bühler, Katja; Thum, Andreas S; Merhof, Dorit

2018-01-01

The larval brain of the fruit fly Drosophila melanogaster is a small, tractable model system for neuroscience. Genes for fluorescent marker proteins can be expressed in defined, spatially restricted neuron populations. Here, we introduce the methods for 1) generating a standard template of the larval central nervous system (CNS), 2) spatial mapping of expression patterns from different larvae into a reference space defined by the standard template. We provide a manually annotated gold standard that serves for evaluation of the registration framework involved in template generation and mapping. A method for registration quality assessment enables the automatic detection of registration errors, and a semi-automatic registration method allows one to correct registrations, which is a prerequisite for a high-quality, curated database of expression patterns. All computational methods are available within the larvalign software package: https://github.com/larvalign/larvalign/releases/tag/v1.0.

Simulating price patterns for tradable green certificates to promote electricity generation from wind

International Nuclear Information System (INIS)

Ford, A.

2007-01-01

This article uses computer simulation to anticipate the price dynamics in a market for Tradable Green Certificates (TGCs). These markets have been used in Europe to promote generation of electricity from renewable resources like wind. Similar markets have been proposed in the United States of America (USA) where the certificates are called Renewable Energy Credits (RECs). The certificates are issued to the generating companies for each megawatt-hour of renewable electricity generation. The companies may sell the certificates in a market, and the revenues from certificate sales provide an extra incentive to invest in new generating capacity. Proponents argue that this market-based incentive can be designed to support government mandates for a growing fraction of electricity generation from renewable sources. In the USA, these mandates are set by the states and are known as Renewable Portfolio Standards (RPS). We simulate the price dynamics of a market designed to support an aggressive mandate for wind generation in the northwestern USA. The simulations show that the certificate price climbs rapidly to the cap in the early years after the market opens. Investors then react to these high prices with construction of new wind capacity. After a few years, wind generation meets, and then exceeds the requirement. We show that this pattern appears again and again when the simulations are repeated with wide variations in the estimates of behavioral parameters. We use the model to study the impact of different trading strategies by the wind companies and by the distribution companies. We also study the simulated market response if the USA adopts the carbon allowance market envisioned in The Climate Stewardship Act. The article concludes with recommendations for policy makers involved in TGC market design. [Author

Simulating price patterns for tradable green certificates to promote electricity generation from wind

International Nuclear Information System (INIS)

Ford, Andrew; Vogstad, Klaus; Flynn, Hilary

2007-01-01

This article uses computer simulation to anticipate the price dynamics in a market for Tradable Green Certificates (TGCs). These markets have been used in Europe to promote generation of electricity from renewable resources like wind. Similar markets have been proposed in the United States of America (USA) where the certificates are called Renewable Energy Credits (RECs). The certificates are issued to the generating companies for each megawatt-hour of renewable electricity generation. The companies may sell the certificates in a market, and the revenues from certificate sales provide an extra incentive to invest in new generating capacity. Proponents argue that this market-based incentive can be designed to support government mandates for a growing fraction of electricity generation from renewable sources. In the USA, these mandates are set by the states and are known as Renewable Portfolio Standards (RPS). We simulate the price dynamics of a market designed to support an aggressive mandate for wind generation in the northwestern USA. The simulations show that the certificate price climbs rapidly to the cap in the early years after the market opens. Investors then react to these high prices with construction of new wind capacity. After a few years, wind generation meets, and then exceeds the requirement. We show that this pattern appears again and again when the simulations are repeated with wide variations in the estimates of behavioral parameters. We use the model to study the impact of different trading strategies by the wind companies and by the distribution companies. We also study the simulated market response if the USA adopts the carbon allowance market envisioned in The Climate Stewardship Act. The article concludes with recommendations for policy makers involved in TGC market design

Movement patterns of the spiny lobster Palinurus elephas (Fabricius, 1787 from a central western Mediterranean protected area

Directory of Open Access Journals (Sweden)

Maria Cristina Follesa

2009-09-01

Full Text Available Movement patterns of the spiny lobster Palinurus elephas were determined from 389 individuals (total tagged 5666 tag-recaptured inside a no-take area of the central western Mediterranean and its surrounding zone. High site association and limited movements in tagged lobsters was observed; 60.4% of lobsters moved less than 2 km from the centre of the area (site of release. No clear relationship between lobster movement pattern and sex or size was observed; however, it seemed that the largest males and females tended to be more resident, thus contributing to the rebuilding of the biomass of local lobsters. Most lobsters undertook migrations in the southwest direction. The increased availability of shelters and food towards the southwest could have contributed to the lobsters’ movement. The results of our research indicate that the small size of the protected area and the scale of the movement exhibited by tagged lobsters allows a proportion of the lobster population to move out of the protected area and become susceptible to capture in the adjacent fishery.

Bursts generate a non-reducible spike-pattern code

Directory of Open Access Journals (Sweden)

Hugo G Eyherabide

2009-05-01

Full Text Available On the single-neuron level, precisely timed spikes can either constitute firing-rate codes or spike-pattern codes that utilize the relative timing between consecutive spikes. There has been little experimental support for the hypothesis that such temporal patterns contribute substantially to information transmission. Using grasshopper auditory receptors as a model system, we show that correlations between spikes can be used to represent behaviorally relevant stimuli. The correlations reflect the inner structure of the spike train: a succession of burst-like patterns. We demonstrate that bursts with different spike counts encode different stimulus features, such that about 20% of the transmitted information corresponds to discriminating between different features, and the remaining 80% is used to allocate these features in time. In this spike-pattern code, the "what" and the "when" of the stimuli are encoded in the duration of each burst and the time of burst onset, respectively. Given the ubiquity of burst firing, we expect similar findings also for other neural systems.

Determining the impact of wind on system costs via the temporal patterns of load and wind generation

International Nuclear Information System (INIS)

Davis, Clay D.; Gotham, Douglas J.; Preckel, Paul V.; Liu, Andrew L.

2013-01-01

Ambitious targets have been set for expanding electricity generation from renewable sources, including wind. Expanding wind power impacts needs for other electricity generating resources. As states plan for increasing levels of wind generation in their portfolio of generation resources it is important to consider how this intermittent resource impacts the need for other generation resources. A case study for Indiana estimates the value of wind capacity and demonstrates how to optimize its level and the levels of other generation resources. Changes are driven by temporal patterns of wind power output and load. System wide impacts are calculated for energy, capacity, and costs under multiple wind expansion scenarios which highlight the geographic characteristics of a systems portfolio of wind generation. The impacts of carbon prices, as proposed in the Bingaman Bill, are considered. Finally, calculations showing the effect increasing levels of wind generation will have on end use Indiana retail rates are included. - Highlights: • We estimate the value of wind capacity. • We determine wind generation's impact on the optimal mix of non-wind generation. • Optimal levels of wind and non-wind generation are determined. • We consider the impact of a carbon price on the optimal mix of resources. • The impact of additional wind capacity on Indiana residential rates is calculated

Seismicity Pattern and Fault Structure in the Central Himalaya Seismic Gap Using Precise Earthquake Hypocenters and their Source Parameters

Science.gov (United States)

Mendoza, M.; Ghosh, A.; Rai, S. S.

2017-12-01

The devastation brought on by the Mw 7.8 Gorkha earthquake in Nepal on 25 April 2015, reconditioned people to the high earthquake risk along the Himalayan arc. It is therefore imperative to learn from the Gorkha earthquake, and gain a better understanding of the state of stress in this fault regime, in order to identify areas that could produce the next devastating earthquake. Here, we focus on what is known as the "central Himalaya seismic gap". It is located in Uttarakhand, India, west of Nepal, where a large (> Mw 7.0) earthquake has not occurred for over the past 200 years [Rajendran, C.P., & Rajendran, K., 2005]. This 500 - 800 km long along-strike seismic gap has been poorly studied, mainly due to the lack of modern and dense instrumentation. It is especially concerning since it surrounds densely populated cities, such as New Delhi. In this study, we analyze a rich seismic dataset from a dense network consisting of 50 broadband stations, that operated between 2005 and 2012. We use the STA/LTA filter technique to detect earthquake phases, and the latest tools contributed to the Antelope software environment, to develop a large and robust earthquake catalog containing thousands of precise hypocentral locations, magnitudes, and focal mechanisms. By refining those locations in HypoDD [Waldhauser & Ellsworth, 2000] to form a tighter cluster of events using relative relocation, we can potentially illustrate fault structures in this region with high resolution. Additionally, using ZMAP [Weimer, S., 2001], we perform a variety of statistical analyses to understand the variability and nature of seismicity occurring in the region. Generating a large and consistent earthquake catalog not only brings to light the physical processes controlling the earthquake cycle in an Himalayan seismogenic zone, it also illustrates how stresses are building up along the décollment and the faults that stem from it. With this new catalog, we aim to reveal fault structure, study

Intraseasonal patterns in coastal plankton biomass off central Chile derived from satellite observations and a biochemical model

Science.gov (United States)

Gomez, Fabian A.; Spitz, Yvette H.; Batchelder, Harold P.; Correa-Ramirez, Marco A.

2017-10-01

Subseasonal (5-130 days) environmental variability can strongly affect plankton dynamics, but is often overlooked in marine ecology studies. We documented the main subseasonal patterns of plankton biomass in the coastal upwelling system off central Chile, the southern part of the Humboldt System. Subseasonal variability was extracted from temporal patterns in satellite data of wind stress, sea surface temperature, and chlorophyll from the period 2003-2011, and from a realistically forced eddy-resolving physical-biochemical model from 2003 to 2008. Although most of the wind variability occurs at submonthly frequencies (< 30 days), we found that the dominant subseasonal pattern of phytoplankton biomass is within the intraseasonal band (30-90 days). The strongest intraseasonal coupling between wind and plankton is in spring-summer, when increased solar radiation enhances the phytoplankton response to upwelling. Biochemical model outputs show intraseasonal shifts in plankton community structure, mainly associated with the large fluctuations in diatom biomass. Diatom biomass peaks near surface during strong upwelling, whereas small phytoplankton biomass peaks at subsurface depths during relaxation or downwelling periods. Strong intraseasonally forced changes in biomass and species composition could strongly impact trophodynamics connections in the ecosystem, including the recruitment of commercially important fish species such as common sardine and anchovy. The wind-driven variability of chlorophyll concentration was connected to mid- and high-latitude atmospheric anomalies, which resemble disturbances with frequencies similar to the tropical Madden-Julian Oscillation.

Broadscale postseismic deformation and lower crustal relaxation in the central Bayankala Block (central Tibetan Plateau) observed using InSAR data

Science.gov (United States)

Zhao, Dezheng; Qu, Chunyan; Shan, Xinjian; Zuo, Ronghu; Liu, Yunhua; Gong, Wenyu; Zhang, Guohong

2018-04-01

We have generated a more than 500 km long postseismic deformation rate map and cumulative displacement time series in the central Bayankala Block of the Tibetan Plateau using ENVISAT/ASAR data from 2003 to 2010 by the π-RATE stacking algorithm. This rate map spans a period of ∼7.2 years and reveals that postseismic motion of 2001 Kokoxili earthquake exhibits a striking signal, dominating crustal deformation of the central Bayankala Block with a cross-fault magnitude ∼9-11 mm/yr in line of sight (LOS) (∼93.1°E). The southern and northern parts of the postseismic deformation field exhibit different patterns and variable magnitudes, reflecting asymmetry of the displacement distribution. Postseismic motion affects eastward extrusion of the central Bayankala Block, which reaches ∼15 km north of the Ganzi-Yushu fault. To further investigate viscoelastic relaxation of the lower crust in this area after approximately two years, E-M, E-M-M and E-S models are constructed. The result shows that the best fit viscosity for the lower crust is about 1 × 1019 Pa·s. Comparison between cumulative displacements resolved by these three models shows that viscoelastic relaxation of the lower crust makes the most significant contribution to postseismic stress relaxation after 2001 event.

Second Harmonic Generation Imaging Analysis of Collagen Arrangement in Human Cornea.

Science.gov (United States)

Park, Choul Yong; Lee, Jimmy K; Chuck, Roy S

2015-08-01

To describe the horizontal arrangement of human corneal collagen bundles by using second harmonic generation (SHG) imaging. Human corneas were imaged with an inverted two photon excitation fluorescence microscope. The excitation laser (Ti:Sapphire) was tuned to 850 nm. Backscatter signals of SHG were collected through a 425/30-nm bandpass emission filter. Multiple, consecutive, and overlapping image stacks (z-stacks) were acquired to generate three dimensional data sets. ImageJ software was used to analyze the arrangement pattern (irregularity) of collagen bundles at each image plane. Collagen bundles in the corneal lamellae demonstrated a complex layout merging and splitting within a single lamellar plane. The patterns were significantly different in the superficial and limbal cornea when compared with deep and central regions. Collagen bundles were smaller in the superficial layer and larger in deep lamellae. By using SHG imaging, the horizontal arrangement of corneal collagen bundles was elucidated at different depths and focal regions of the human cornea.

The Lycaenid Central Symmetry System: Color Pattern Analysis of the Pale Grass Blue Butterfly Zizeeria maha.

Science.gov (United States)

Iwata, Masaki; Taira, Wataru; Hiyama, Atsuki; Otaki, Joji M

2015-06-01

The nymphalid groundplan has been proposed to explain diverse butterfly wing color patterns. In this model, each symmetry system is composed of a core element and a pair of paracore elements. The development of this elemental configuration has been explained by the induction model for positional information. However, the diversity of color patterns in other butterfly families in relation to the nymphalid groundplan has not been thoroughly examined. Here, we examined aberrant color pattern phenotypes of a lycaenid butterfly, Zizeeria maha, from mutagenesis and plasticity studies as well as from field surveys. In several mutants, the third and fourth spot arrays were coordinately positioned much closer to the discal spot in comparison to the normal phenotype. In temperature-shock types, the third and fourth array spots were elongated inwardly or outwardly from their normal positions. In field-caught spontaneous mutants, small black spots were located adjacent to normal black spots. Analysis of these aberrant phenotypes indicated that the spots belonging to the third and fourth arrays are synchronously changeable in position and shape around the discal spot. Thus, these arrays constitute paracore elements of the central symmetry system of the lycaenid butterflies, and the discal spot comprises the core element. These aberrant phenotypes can be explained by the black-inducing signals that propagate from the prospective discal spot, as predicted by the induction model. These results suggest the existence of long-range developmental signals that cover a large area of a wing not only in nymphalid butterflies, but also in lycaenid butterflies.

Dietary patterns of obese and normal-weight women of reproductive age in urban slum areas in Central Jakarta.

Science.gov (United States)

Yulia; Khusun, Helda; Fahmida, Umi

2016-07-01

Developing countries including Indonesia imperatively require an understanding of factors leading to the emerging problem of obesity, especially within low socio-economic groups, whose dietary pattern may contribute to obesity. In this cross-sectional study, we compared the dietary patterns and food consumption of 103 obese and 104 normal-weight women of reproductive age (19-49 years) in urban slum areas in Central Jakarta. A single 24-h food recall was used to assess energy and macronutrient intakes (carbohydrate, protein and fat) and calculate energy density. A principal component analysis was used to define the dietary patterns from the FFQ. Obese women had significantly higher intakes of energy (8436·6 (sd 2358·1) v. 7504·4 (sd 1887·8) kJ (2016·4 (sd 563·6) v. 1793·6 (sd 451·2) kcal)), carbohydrate (263·9 (sd 77·0) v. 237·6 (sd 63·0) g) and fat (83·11 (sd 31·3) v. 70·2 (sd 26·1) g) compared with normal-weight women; however, their protein intake (59·4 (sd 19·1) v. 55·9 (sd 18·5) g) and energy density (8·911 (sd 2·30) v. 8·58 (sd 1·88) kJ/g (2·13 (sd 0·55) v. 2·05 (sd 0·45) kcal/g)) did not differ significantly. Two dietary patterns were revealed and subjectively named 'more healthy' and 'less healthy'. The 'less healthy' pattern was characterised by the consumption of fried foods (snacks, soyabean and roots and tubers) and meat and poultry products, whereas the more healthy pattern was characterised by the consumption of seafood, vegetables, eggs, milk and milk products and non-fried snacks. Subjects with a high score for the more healthy pattern had a lower obesity risk compared with those with a low score. Thus, obesity is associated with high energy intake and unhealthy dietary patterns characterised by consumption of oils and fats through fried foods and snacks.

Viewpoint: Central adjudication of myocardial infarction in outcome-driven clinical trials--common patterns in TRITON, RECORD, and PLATO?

Science.gov (United States)

Serebruany, Victor L; Atar, Dan

2012-09-01

Central adjudication in randomised controlled outcome-driven trials represents a traditional approach to maintain data integrity by applying uniformed rules for assessment of clinical events. It was the purpose of this investigation to determine the patterns of myocardial infarction (MI) adjudication in the TRITON, RECORD, and PLATO trials. We were matching centrally-adjudicated MI's (CAMI's) from the official trial publication with the site-reported MI (SRMI's) count from the Food and Drug Administration's secondary analyses for the investigational compounds prasugrel (TRITON), rosiglitazone (RECORD), and ticagrelor (PLATO). CAMI numbers showed a remarkable discrepancy to SRMI's by more than a doubling of the difference: from 72 to 145 events in TRITON favoring prasugrel (from a hazard ratio [HR]=0.76, p=0.08; to a HR=0.76, p<0.001), and from 44 to 89 events in favour of ticagrelor in PLATO (from a HR=0.94, p=0.095; to a HR=0.84, p<0.001). In contrast, in the RECORD trial, the CAMI count was less than the SRMI count (from 24 to 8 events, from a HR=1.42, p=0.93; to a HR=1.14, p=0.96), in this case diminishing cardiovascular hazards in favour of rosiglitazone. In conclusion, central adjudication in the TRITON, the RECORD, and the PLATO trial turned out to have a critical impact on study outcomes. Trial publications should in the future include site-reported major efficacy and safety endpoints to preserve data integrity. The regulatory authorities should consider independent audits when there is a major disagreement between centrally adjudicated and site reported events influencing the results of a major clinical trial.

Precise colocalization of interacting structural and pigmentary elements generates extensive color pattern variation in Phelsuma lizards

Science.gov (United States)

2013-01-01

Background Color traits in animals play crucial roles in thermoregulation, photoprotection, camouflage, and visual communication, and are amenable to objective quantification and modeling. However, the extensive variation in non-melanic pigments and structural colors in squamate reptiles has been largely disregarded. Here, we used an integrated approach to investigate the morphological basis and physical mechanisms generating variation in color traits in tropical day geckos of the genus Phelsuma. Results Combining histology, optics, mass spectrometry, and UV and Raman spectroscopy, we found that the extensive variation in color patterns within and among Phelsuma species is generated by complex interactions between, on the one hand, chromatophores containing yellow/red pteridine pigments and, on the other hand, iridophores producing structural color by constructive interference of light with guanine nanocrystals. More specifically, we show that 1) the hue of the vivid dorsolateral skin is modulated both by variation in geometry of structural, highly ordered narrowband reflectors, and by the presence of yellow pigments, and 2) that the reflectivity of the white belly and of dorsolateral pigmentary red marks, is increased by underlying structural disorganized broadband reflectors. Most importantly, these interactions require precise colocalization of yellow and red chromatophores with different types of iridophores, characterized by ordered and disordered nanocrystals, respectively. We validated these results through numerical simulations combining pigmentary components with a multilayer interferential optical model. Finally, we show that melanophores form dark lateral patterns but do not significantly contribute to variation in blue/green or red coloration, and that changes in the pH or redox state of pigments provide yet another source of color variation in squamates. Conclusions Precisely colocalized interacting pigmentary and structural elements generate extensive

Angular pattern of minijet transverse energy flow in hadron and nuclear collisions

International Nuclear Information System (INIS)

Leonidov, A.V.; Ostrovsky, D.M.

2002-01-01

The azimuthal asymmetry of a minijet system produced at the early stage of nucleon-nucleon and nuclear collisions in a central rapidity window is studied. We show that, in pp collisions, the minijet-transverse-energy production in a central rapidity window is essentially unbalanced in azimuth because of asymmetric contributions in which only one minijet hits the acceptance window. We further study the angular pattern of the transverse-energy flow generated by semihard degrees of freedom at the early stage of high-energy nuclear collisions and its dependence on the number of semihard collisions in the models either including or neglecting soft contributions to the inelastic cross section at RHIC and LHC energies, as well as on the choice of infrared cutoff

Angular pattern of minijet transverse energy flow in hadron and nuclear collisions

International Nuclear Information System (INIS)

Leonidov, A.V.; Ostrovsky, D.M.

2000-01-01

The azimuthal asymmetry of a minijet system produced at the early stage of nucleon-nucleon and nuclear collisions in a central rapidity window is studied. We show that in pp collisions the minijet transverse energy production in a central rapidity window is essentially unbalanced in the azimuth due to asymmetric contributions in which only one minijet hits the acceptance window. We further study the angular pattern of the transverse energy flow generated by the semihard degrees of freedom at the early stage of high energy nuclear collisions and its dependence on the number of semihard collisions in the models both including and neglecting soft contributions to the inelastic cross section at RHIC and LHC energies as well as on the choice of the infrared cutoff. (orig.)

Dynamic contrast enhancement in widefield microscopy using projector-generated illumination patterns

International Nuclear Information System (INIS)

Samson, Edward Carlo; Blanca, Carlo Mar

2007-01-01

We present a simple and cost-effective optical protocol to realize contrast-enhancement imaging (such as dark-field, optical-staining and oblique illumination microscopy) of transparent samples on a conventional widefield microscope using commercial multimedia projectors. The projector functions as both light source and mask generator implemented by creating slideshows of the filters projected along the illumination planes of the microscope. The projected optical masks spatially modulate the distribution of the incident light to selectively enhance structures within the sample according to spatial frequency thereby increasing the image contrast of translucent biological specimens. Any amplitude filter can be customized and dynamically controlled so that switching from one imaging modality to another involves a simple slide transition and can be executed at a keystroke with no physical filters and no moving optical parts. The method yields an image contrast of 89-96% comparable with standard enhancement techniques. The polarization properties of the projector are then utilized to discriminate birefringent and non-birefringent sites on the sample using single-shot, simultaneous polarization and optical-staining microscopy. In addition to dynamic pattern generation and polarization, the projector also provides high illumination power and spectral excitation selectivity through its red-green-blue (RGB) channels. We exploit this last property to explore the feasibility of using video projectors to selectively excite stained samples and perform fluorescence imaging in tandem with reflectance and polarization reflectance microscopy

Centralized electricity generation in Africa

International Nuclear Information System (INIS)

Jaujay, J.

2000-01-01

In Africa, over 90 per cent of the suburban and rural populations do not have access to electricity, even if it represents the engine and consequence of change on the continent. A global approach represents the best way to meet the extensive needs of the continent. The author briefly reviewed the recent projects implemented in Africa to meet the increasing demand. Diesel generators were used to satisfy demand in small electrical sectors (less than 1000 MW), hydroelectricity or combustion turbines were used for medium electrical sectors (1000 to 5000 MW). A discussion of the technologies followed, touching on diesel electric stations and combustion turbines. Both methods meet environmental standards as they apply to emission control and noise control. The choice between the two technologies must be based on required unit power, site isolation, access to gas, and the cost of available combustibles. Hydroelectric power has great potential in the sub-Sahara region, and the challenges faced by each project are similar: difficulty in finding the required financing, meeting the environmental constraints, and the distribution of the energy. A modular nuclear reactor project for the generation of electricity is being developed by ESKOM Enterprises, in association with the British Nuclear Fuel Limited and PECCO and progress will be closely monitored. Decision makers must ensure that appropriate decisions are made in a reasonable time frame to allow sufficient time to develop a project to implementation. Demand requirements must be examined closely, technology adequately selected in order to come up with a financing plan. 4 tabs

Pattern of Maxillofacial Surgical Conditions in North Central Nigeria ...

African Journals Online (AJOL)

2018-02-07

com on Wednesday, February 7, 2018, IP: 197.89.67.237] ... Table 2: Profile of orofacial surgical conditions seen and treated over 5 years during outreach programmes in ..... The North Central zone of the country, with a population of 20.2 ...

On the influence of surface patterning on tissue self-assembly and mechanics.

Science.gov (United States)

Coppola, Valerio; Ventre, Maurizio; Natale, Carlo F; Rescigno, Francesca; Netti, Paolo A

2018-04-28

Extracellular matrix assembly and composition influence the biological and mechanical functions of tissues. Developing strategies to control the spatial arrangement of cells and matrix is of central importance for tissue engineering-related approaches relying on self-assembling and scaffoldless processes. Literature reports demonstrated that signals patterned on material surfaces are able to control cell positioning and matrix orientation. However, the mechanisms underlying the interactions between material signals and the structure of the de novo synthesized matrix are far from being thoroughly understood. In this work, we investigated the ordering effect provided by nanoscale topographic patterns on the assembly of tissue sheets grown in vitro. We stimulated MC3T3-E1 preosteoblasts to produce and assemble a collagen-rich matrix on substrates displaying patterns with long- or short-range order. Then, we investigated microstructural features and mechanical properties of the tissue in uniaxial tension. Our results demonstrate that patterned material surfaces are able to control the initial organization of cells in close contact to the surface; then cell-generated contractile forces profoundly remodel tissue structure towards mechanically stable spatial patterns. Such a remodelling effect acts both locally, as it affects cell and nuclear shape and globally, by affecting the gross mechanical response of the tissue. Such an aspect of dynamic interplay between cells and the surrounding matrix must be taken into account when designing material platform for the in vitro generation of tissue with specific microstructural assemblies. Copyright © 2018 John Wiley & Sons, Ltd.

Directional layouts in central lowland Maya settlement

DEFF Research Database (Denmark)

Bevan, Andrew; Jobbová, Eva; Helmke, Christophe

2013-01-01

This paper suggests the existence of non-random, directional patterns in the location of housemounds across the Late Classic Maya settlement landscape at Baking Pot, Belize, and then explores the wider implications of this patterning in the central Maya lowlands. It introduces an anisotropic method...

Simulations of Ar gas-puff Z-pinch radiation sources with double shells and central jets on the Z generator

Science.gov (United States)

Tangri, V.; Harvey-Thompson, A. J.; Giuliani, J. L.; Thornhill, J. W.; Velikovich, A. L.; Apruzese, J. P.; Ouart, N. D.; Dasgupta, A.; Jones, B.; Jennings, C. A.

2016-10-01

Radiation-magnetohydrodynamic simulations using the non-local thermodynamic equilibrium Mach2-Tabular Collisional-Radiative Equilibrium code in (r, z) geometry are performed for two pairs of recent Ar gas-puff Z-pinch experiments on the refurbished Z generator with an 8 cm diameter nozzle. One pair of shots had an outer-to-inner shell mass ratio of 1:1.6 and a second pair had a ratio of 1:1. In each pair, one of the shots had a central jet. The experimental trends in the Ar K-shell yield and power are reproduced in the calculations. However, the K-shell yield and power are significantly lower than the other three shots for the case of a double-shell puff of 1:1 mass ratio and no central jet configuration. Further simulations of a hypothetical experiment with the same relative density profile of this configuration, but higher total mass, show that the coupled energy from the generator and the K-shell yield can be increased to levels achieved in the other three configurations, but not the K-shell power. Based on various measures of effective plasma radius, the compression in the 1:1 mass ratio and no central jet case is found to be less because the plasma inside the magnetic piston is hotter and of lower density. Because of the reduced density, and the reduced radiation cooling (which is proportional to the square of the density), the core plasma is hotter. Consequently, for the 1:1 outer-to-inner shell mass ratio, the load mass controls the yield and the center jet controls the power.

Decreasing overweight and central fat patterning with Westernization among the Inuit in Greenland and Inuit migrants

DEFF Research Database (Denmark)

Bjerregaard, P; Jørgensen, M E; Andersen, S

2002-01-01

OBJECTIVE: To analyse overweight, obesity and central fat patterning among the Inuit of Greenland and Inuit migrants in Denmark and their relation to Westernization. DESIGN: Cross-sectional, population-based epidemiological study. SUBJECTS: A total of 2046 adult Greenlanders (Inuit), 61% of those...... invited to participate, living in three areas of Greenland and in Denmark. MEASUREMENTS: Height, weight, waist and hip circumferences were measured and body mass index (BMI in kg/m(2)) and waist-hip ratio calculated. Sociocultural information was obtained by questionnaire and interview. Westernization...... was estimated by language and place of residence. RESULTS: The prevalence of obesity (>or=30 kg/m(2)) was 16 and 22% among men and women in Greenland (P=0.004), and 12 and 11%, respectively, in Denmark (NS). Westernization was accompanied by a decrease in the proportion of obese people, in particular among...

Diet-related buccal dental microwear patterns in Central African Pygmy foragers and Bantu-speaking farmer and pastoralist populations.

Directory of Open Access Journals (Sweden)

Alejandro Romero

Full Text Available Pygmy hunter-gatherers from Central Africa have shared a network of socioeconomic interactions with non-Pygmy Bantu speakers since agropastoral lifestyle spread across sub-Saharan Africa. Ethnographic studies have reported that their diets differ in consumption of both animal proteins and starch grains. Hunted meat and gathered plant foods, especially underground storage organs (USOs, are dietary staples for pygmies. However, scarce information exists about forager-farmer interaction and the agricultural products used by pygmies. Since the effects of dietary preferences on teeth in modern and past pygmies remain unknown, we explored dietary history through quantitative analysis of buccal microwear on cheek teeth in well-documented Baka pygmies. We then determined if microwear patterns differ among other Pygmy groups (Aka, Mbuti, and Babongo and between Bantu-speaking farmer and pastoralist populations from past centuries. The buccal dental microwear patterns of Pygmy hunter-gatherers and non-Pygmy Bantu pastoralists show lower scratch densities, indicative of diets more intensively based on nonabrasive foodstuffs, compared with Bantu farmers, who consume larger amounts of grit from stoneground foods. The Baka pygmies showed microwear patterns similar to those of ancient Aka and Mbuti, suggesting that the mechanical properties of their preferred diets have not significantly changed through time. In contrast, Babongo pygmies showed scratch densities and lengths similar to those of the farmers, consistent with sociocultural contacts and genetic factors. Our findings support that buccal microwear patterns predict dietary habits independent of ecological conditions and reflect the abrasive properties of preferred or fallback foods such as USOs, which may have contributed to the dietary specializations of ancient human populations.

Lack of differential pattern in central adiposity and metabolic syndrome in Barrett's esophagus and gastroesophageal reflux disease.

LENUS (Irish Health Repository)

Healy, L A

2012-02-01

Obesity is an established risk factor for esophageal adenocarcinoma, although the mechanism is unclear. A pathway from reflux to inflammation through metaplasia is the dominant hypothesis, and an added role relating to visceral adiposity and the metabolic syndrome has been mooted in Barrett\\'s esophagus (BE) patients. Whether BE differs from gastroesophageal reflux disease (GERD) in obesity and metabolic syndrome profiles is unclear, and this was the focus of this study. Patients with proven BE or GERD were randomly selected from the unit data registry and invited to attend for metabolic syndrome screening, anthropometry studies including segmental body composition analysis, and laboratory tests including fasting lipids, insulin, and C-reactive protein. Metabolic syndrome was defined using the National Cholesterol Education Program (NCEP) and the International Diabetes Federation (IDF) criteria. One hundred and eighteen BE patients and 113 age- and sex-matched GERD controls were studied. The incidence of obesity (body mass index >30 kg\\/m(2)) was 36% and 38%, respectively, with the pattern of fat deposition predominantly central and an estimated trunk fat mass of 13 and 14 kg, respectively. Using the NCEP criteria, metabolic syndrome was significantly more common in the BE cohort (30% vs 20%, P < 0.05), but there was no significant difference using IDF criteria (42% vs 37%, P= 0.340). Central obesity and the metabolic syndrome are common in both Barrett\\'s and GERD cohorts, but not significantly different, suggesting that central obesity and the metabolic syndrome does not per se impact on the development of BE in a reflux population. In BE, the importance of obesity and the metabolic syndrome in disease progression merits further study.

Post-release survival and movements patterns of roosterfish (Nematistius pectoralis off the Central American coastline

Directory of Open Access Journals (Sweden)

Chugey A Sepulveda

2015-03-01

Full Text Available Acoustic telemetry was used to assess immediate post-release survival and track the short-term movement patterns of roosterfish Nematistius pectoralis between 2008 and 2010. Seven roosterfish (85 to 146 cm fork length, FL were continuously tracked along the Central American coastline for periods of up to 28 h following capture on recreational fishing tackle. All seven roosterfish were initially captured and spent the duration of the track period proximal to the coastline in waters <100 m of depth. From depth records and horizontal movements, it was determined that all seven roosterfish survived the acute effects of capture. The greatest depth achieved by any of the tracked individuals was 62 m and collectively roosterfish spent over 90% of the track records between the surface and 12 m. For all tracks, fish size showed no effect on maximum or average dive depth and the average day (7 ± 2 m and night (6 ± 2 m depths were similar among individuals. Mean water temperature for all tracks was 28 ± 1°C, with the lowest temperature experienced at depth being 23°C. Total horizontal movements from the roosterfish in this study ranged from 14.7 to 42.2 km and averaged 1.5 ± 0.4 km h-1. Data on movements in relation to bathymetry, prey presence and habitat structure are discussed. Collectively, these data provide insight into the immediate post-release disposition and short-term movements of this poorly studied species along the coast of Central America.

What caused the cool summer over northern Central Asia, East Asia and central North America during 2009?

International Nuclear Information System (INIS)

Ha, Kyung-Ja; Chu, Jung-Eun; Lee, June-Yi; Wang, Bin; Hameed, Saji N; Watanabe, Masahiro

2012-01-01

Cool and wet weather conditions hit northern Central Asia, East Asia and central North America during the 2009 summer in concert with a strong jet stream and a prominent meandering upper-level circulation in the Northern Hemisphere mid-latitudes despite the fact that the year 2009 is the fifth warmest year globally in the modern record. It is found that the conspicuous atmospheric variability in the entire Northern Hemisphere mid-latitudes during the summer of 2009 was caused by a combination of teleconnections associated with significant tropical thermal forcings, strong polar forcing, and interaction between high-frequency weather events and climate anomalies. The strong negative circumglobal teleconnection pattern associated with the deficient Indian summer monsoon rainfall and developing El Niño condition was the major contributor to the cool and wet summer in June. On the other hand, the July weather conditions were attributable to the high-latitude impact of the unprecedented negative Arctic Oscillation, together with the Rossby wave response to the subtropical heating generated by convective activities over the Western North Pacific summer monsoon region. It is also noted that enhanced storm track activity and frequent cold surges from high-latitudes may have played a role in the cool and wet summer over the regions of interest. (letter)

Research management at the Central Electricity Generating Board

International Nuclear Information System (INIS)

Broom, T.

1986-01-01

CEGB is responsible for power generation and transmission in England and Wales, and has a yearly production of some 230 TWh. There are three main fields of research: conventional generation and transmission, nuclear generation and environmental consequences of electricity generation. All laboratories carry out research in each field, though there are definite concentrations of specialities. The organisation of the research management changed emphasis in 1981 from an 'areal' (managing of individual institutes) to a topical approach (responsibilities for research fields). Good research requires good personnel, but also care on the part of the manager for the personal interests of the staff. There must be good cooperation between the researchers themselves, between researchers and managers, and between CEGB staff and researchers elsewhere. It is considered of prime importance that the researchers be true experts in their fields and that they maintain their scientific integrity. Other information is obtained by exchanging reports with comparable organisations, e.g. the KEMA in The Netherlands. Such an exchange requires mutual trust and research managers must therefore behave as true ambassadors. (Auth.)

Pattern of ground deformation in Kathmandu valley during 2015 Gorkha Earthquake, central Nepal

Science.gov (United States)

Ghimire, S.; Dwivedi, S. K.; Acharya, K. K.

2016-12-01

The 25th April 2015 Gorkha Earthquake (Mw=7.8) epicentered at Barpak along with thousands of aftershocks released seismic moment nearly equivalent to an 8.0 Magnitude earthquake rupturing a 150km long fault segment. Although Kathmandu valley was supposed to be severely devastated by such major earthquake, post earthquake scenario is completely different. The observed destruction is far less than anticipated as well as the spatial pattern is different than expected. This work focuses on the behavior of Kathmandu valley sediments during the strong shaking by the 2015 Gorkha Earthquake. For this purpose spatial pattern of destruction is analyzed at heavily destructed sites. To understand characteristics of subsurface soil 2D-MASW survey was carried out using a 24-channel seismograph system. An accellerogram recorded by Nepal Seismological Center was analyzed to characterize the strong ground motion. The Kathmandu valley comprises fluvio-lacustrine deposit with gravel, sand, silt and clay along with few exposures of basement rocks within the sediments. The observations show systematic repetition of destruction at an average interval of 2.5km mostly in sand, silt and clay dominated formations. Results of 2D-MASW show the sites of destruction are characterized by static deformation of soil (liquefaction and southerly dipping cracks). Spectral analysis of the accelerogram indicates maximum power associated with frequency of 1.0Hz. The result of this study explains the observed spatial pattern of destruction in Kathmandu valley. This is correlated with the seismic energy associated with the frequency of 1Hz, which generates an average wavelength of 2.5km with an average S-wave velocity of 2.5km/s. The cumulative effect of dominant frequency and associated wavelength resulted in static deformation of surface soil layers at an average interval of 2.5km. This phenomenon clearly describes the reason for different scenario than that was anticipated in Kathmandu valley.

Atypical Mg-poor Milky Way Field Stars with Globular Cluster Second-generation-like Chemical Patterns

Energy Technology Data Exchange (ETDEWEB)

Fernández-Trincado, J. G.; Geisler, D.; Tang, B.; Villanova, S.; Mennickent, R. E. [Departamento de Astronomía, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Zamora, O.; García-Hernández, D. A.; Dell’Agli, F.; Prieto, Carlos Allende [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Souto, Diogo; Cunha, Katia [Observatório Nacional, Rua Gal. José Cristino 77, Rio de Janeiro, RJ—20921-400 (Brazil); Schiavon, R. P. [Astrophysics Research Institute, Liverpool John Moores University, 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Hasselquist, Sten [New Mexico State University, Las Cruces, NM 88003 (United States); Shetrone, M. [University of Texas at Austin, McDonald Observatory, Fort Davis, TX 79734 (United States); Vieira, K. [Centro de Investigaciones de Astronomía, AP 264, Mérida 5101-A (Venezuela, Bolivarian Republic of); Zasowski, G. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Sobeck, J.; Hayes, C. R.; Majewski, S. R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22903 (United States); Placco, V. M., E-mail: jfernandezt@astro-udec.cl, E-mail: jfernandezt87@gmail.com [Department of Physics and JINA Center for the Evolution of the Elements, University of Notre Dame, Notre Dame, IN 46556 (United States); and others

2017-09-01

We report the peculiar chemical abundance patterns of 11 atypical Milky Way (MW) field red giant stars observed by the Apache Point Observatory Galactic Evolution Experiment (APOGEE). These atypical giants exhibit strong Al and N enhancements accompanied by C and Mg depletions, strikingly similar to those observed in the so-called second-generation (SG) stars of globular clusters (GCs). Remarkably, we find low Mg abundances ([Mg/Fe] < 0.0) together with strong Al and N overabundances in the majority (5/7) of the metal-rich ([Fe/H] ≳ −1.0) sample stars, which is at odds with actual observations of SG stars in Galactic GCs of similar metallicities. This chemical pattern is unique and unprecedented among MW stars, posing urgent questions about its origin. These atypical stars could be former SG stars of dissolved GCs formed with intrinsically lower abundances of Mg and enriched Al (subsequently self-polluted by massive AGB stars) or the result of exotic binary systems. We speculate that the stars Mg-deficiency as well as the orbital properties suggest that they could have an extragalactic origin. This discovery should guide future dedicated spectroscopic searches of atypical stellar chemical patterns in our Galaxy, a fundamental step forward to understanding the Galactic formation and evolution.

Development of the control assembly pattern and dynamic analysis of the Generation IV large gas-cooled fast reactor (GFR)

Energy Technology Data Exchange (ETDEWEB)

Girardin, G.

2009-07-15

During the past ten years, different independent factors, such as the rapidly increasing worldwide demand in energy, societal concerns about greenhouse gas emissions, and the high and volatile prices for fossil fuels, have contributed to the renewed interest in nuclear technology. In this context, the Generation IV International Forum (GIF) launched the initiative to collaborate on the research and development efforts needed for the next generation of nuclear reactors. A particular goal set for Generation IV systems is closure of the nuclear fuel cycle; they are expected to offer a better utilization of natural resources, as also a minimization of long-lived radioactive wastes. Among the systems selected by the GIF, the Gas-cooled Fast Reactor (GFR) is a highly innovative system with advanced fuel geometry and materials. The principal aim of the present research is to develop and qualify the control assembly (CA) pattern and corresponding CA implementation scheme for the 2400 MWth reference GFR design. The work has been carried out in three successive phases: (1) validation of the neutronics tools, (2) the CA pattern development and related static analysis, and (3) dynamic core behaviour studies for hypothetical CA driven transients. The deterministic code system ERANOS and its associated nuclear data libraries for fast reactors were developed and validated for sodium-cooled reactors. In order to validate ERANOS for GFR applications, a systematic reanalysis of the GFR-relevant integral data generated at PSI during the GCFR-PROTEUS experimental program of the 1970’s was undertaken. The reference PROTEUS test lattice has been analyzed with ERANOS-2.0 and its associated, adjusted nuclear data library ERALIB1. Benchmark calculations were performed with the Monte Carlo code MCNPX, allowing one to both check the deterministic results and to analyze the sensitivity to different modern data libraries. For the main reaction rate ratios, the new analysis of the GCFR

Development of the control assembly pattern and dynamic analysis of the Generation IV large gas-cooled fast reactor (GFR)

International Nuclear Information System (INIS)

Girardin, G.

2009-07-01

During the past ten years, different independent factors, such as the rapidly increasing worldwide demand in energy, societal concerns about greenhouse gas emissions, and the high and volatile prices for fossil fuels, have contributed to the renewed interest in nuclear technology. In this context, the Generation IV International Forum (GIF) launched the initiative to collaborate on the research and development efforts needed for the next generation of nuclear reactors. A particular goal set for Generation IV systems is closure of the nuclear fuel cycle; they are expected to offer a better utilization of natural resources, as also a minimization of long-lived radioactive wastes. Among the systems selected by the GIF, the Gas-cooled Fast Reactor (GFR) is a highly innovative system with advanced fuel geometry and materials. The principal aim of the present research is to develop and qualify the control assembly (CA) pattern and corresponding CA implementation scheme for the 2400 MWth reference GFR design. The work has been carried out in three successive phases: (1) validation of the neutronics tools, (2) the CA pattern development and related static analysis, and (3) dynamic core behaviour studies for hypothetical CA driven transients. The deterministic code system ERANOS and its associated nuclear data libraries for fast reactors were developed and validated for sodium-cooled reactors. In order to validate ERANOS for GFR applications, a systematic reanalysis of the GFR-relevant integral data generated at PSI during the GCFR-PROTEUS experimental program of the 1970’s was undertaken. The reference PROTEUS test lattice has been analyzed with ERANOS-2.0 and its associated, adjusted nuclear data library ERALIB1. Benchmark calculations were performed with the Monte Carlo code MCNPX, allowing one to both check the deterministic results and to analyze the sensitivity to different modern data libraries. For the main reaction rate ratios, the new analysis of the GCFR

Soil Communities of Central Park, New York City: A Biodiversity Melting Pot

Science.gov (United States)

Ramirez, K. S.; Leff, J. W.; Wall, D. H.; Fierer, N.

2013-12-01

The majority of earth's biodiversity lives in and makes up the soil, but the majority of soil biodiversity has yet to be characterized or even quantified. This may be especially true of urban soil systems. The last decade of advances in molecular, technical and bioinformatic techniques have contributed greatly to our understanding of belowground biodiversity, from global distribution to species counts. Yet, much of this work has been done in ';natural' systems and it is not known if established patterns of distribution, especially in relation to soil factors hold up in urban soils. Urban soils are intensively managed and disturbed, often by effects unique to urban settings. It remains unclear how urban pressures influence soil biodiversity, or if there is a defined or typical ';urban soil community'. Here we describe a study to examine the total soil biodiversity - Bacteria, Archaea and Eukarya- of Central Park, New York City and test for patterns of distribution and relationships to soil characteristics. We then compare the biodiversity of Central Park to 57 global soils, spanning a number of biomes from Alaska to Antarctica. In this way we can identify similarities and differences in soil communities of Central Park to soils from ';natural' systems. To generate a broad-scale survey of total soil biodiversity, 596 soil samples were collected from across Central Park (3.41 km2). Soils varied greatly in vegetation cover and soil characteristics (pH, moisture, soil C and soil N). Using high-throughput Illumina sequencing technology we characterized the complete soil community from 16S rRNA (Bacteria and Archaea) and 18S rRNA gene sequences (Eukarya). Samples were rarified to 40,000 sequences per sample. To compare Central Park to the 57 global soils the complete soil community of the global soils was also characterized using Illumina sequencing technology. All samples were rarified to 40,000 sequences per sample. The total measured biodiversity in Central Park was

The internal flow pattern analysis of a tidal power turbine operating on bidirectional generation-pumping

International Nuclear Information System (INIS)

Luo, Y Y; Xiao, Y X; Wang, Z W

2013-01-01

Using tidal energy can reduce environment pollution, save conventional energy and improve energy structure, hence it presents great advantage and is developing potential. Influenced by flood tide and low tide, a fully functional tidal power station needs to experience six operating modes, including bidirectional generation, pumping and sluice; the internal unsteady flow pattern and dynamic characters are very complicated. Based on a bidirectional tidal generator unit, three-dimensional unsteady flows in the flow path were calculated for four typical operating conditions with the pressure pulsation characteristics analyzed. According to the numerical results, the internal flow characteristics in the flow path were discussed. The influence of gravity to the hydraulic performance and flow characteristics were analysed. The results provide a theoretical analysis method of the hydraulic optimization design of the same type unit as well as a direction for stable operation and optimal scheduling of existing tidal power unit

Modelling Behaviour Patterns of Pedestrians for Mobile Robot Trajectory Generation

Directory of Open Access Journals (Sweden)

Yusuke Tamura

2013-08-01

Full Text Available Robots are expected to be operated in environments where they coexist with humans, such as shopping malls and offices. Both the safety and efficiency of a robot are necessary in such environments. To achieve this, pedestrian behaviour should be accurately predicted. However, the behaviour is uncertain and cannot be easily predicted. This paper proposes a probabilistic method of determining pedestrian trajectory based on an estimation of pedestrian behaviour patterns. The proposed method focuses on the specific behaviour of pedestrians around the robot. The proposed model classifies the behaviours of pedestrians into definite patterns. The behaviour patterns, distribution of the positions of the pedestrians, and the direction of each behaviour pattern are determined by learning through observation. The behaviour pattern of a pedestrian can be estimated correctly by a likelihood calculation. A robot decides to move with an emphasis on either safety or efficiency depending on the result of the pattern estimation. If the pedestrian trajectory follows a known behaviour pattern, the robot would move with an emphasis on efficiency because the pedestrian trajectory can be predicted. Otherwise, the robot would move with an emphasis on safety because the behaviour of the pedestrian cannot be predicted. Experimental results show that robots can move efficiently and safely when passing by a pedestrian by applying the proposed method.

Student-generated questions during chemistry lectures: Patterns, self-appraisals, and relations with motivational beliefs and achievement

Science.gov (United States)

Bergey, Bradley W.

Self-generated questions are a central mechanism for learning, yet students' questions are often infrequent during classroom instruction. As a result, little is known about the nature of student questioning during typical instructional contexts such as listening to a lecture, including the extent and nature of student-generated questions, how students evaluate their questions, and the relations among questions, motivations, and achievement. This study examined the questions undergraduate students (N = 103) generated during 8 lectures in an introductory chemistry course. Students recorded and appraised their question in daily question logs and reported lecture-specific self-efficacy beliefs. Self-efficacy, personal interest, goal orientations, and other motivational self-beliefs were measured before and after the unit. Primary analyses included testing path models, multiple regressions, and latent class analyses. Overall, results indicated that several characteristics of student questioning during lectures were significantly related to various motivations and achievement. Higher end-of-class self-efficacy was associated with fewer procedural questions and more questions that reflected smaller knowledge deficits. Lower exam scores were associated with questions reflecting broader knowledge deficits and students' appraisals that their questions had less value for others than for themselves. Individual goal orientations collectively and positively predicted question appraisals. The questions students generated and their relations with motivational variables and achievement are discussed in light of the learning task and academic context.

Spatial pattern enhances ecosystem functioning in an African savanna.

Directory of Open Access Journals (Sweden)

Robert M Pringle

2010-05-01

Full Text Available The finding that regular spatial patterns can emerge in nature from local interactions between organisms has prompted a search for the ecological importance of these patterns. Theoretical models have predicted that patterning may have positive emergent effects on fundamental ecosystem functions, such as productivity. We provide empirical support for this prediction. In dryland ecosystems, termite mounds are often hotspots of plant growth (primary productivity. Using detailed observations and manipulative experiments in an African savanna, we show that these mounds are also local hotspots of animal abundance (secondary and tertiary productivity: insect abundance and biomass decreased with distance from the nearest termite mound, as did the abundance, biomass, and reproductive output of insect-eating predators. Null-model analyses indicated that at the landscape scale, the evenly spaced distribution of termite mounds produced dramatically greater abundance, biomass, and reproductive output of consumers across trophic levels than would be obtained in landscapes with randomly distributed mounds. These emergent properties of spatial pattern arose because the average distance from an arbitrarily chosen point to the nearest feature in a landscape is minimized in landscapes where the features are hyper-dispersed (i.e., uniformly spaced. This suggests that the linkage between patterning and ecosystem functioning will be common to systems spanning the range of human management intensities. The centrality of spatial pattern to system-wide biomass accumulation underscores the need to conserve pattern-generating organisms and mechanisms, and to incorporate landscape patterning in efforts to restore degraded habitats and maximize the delivery of ecosystem services.

Spatial pattern enhances ecosystem functioning in an African savanna.

Science.gov (United States)

Pringle, Robert M; Doak, Daniel F; Brody, Alison K; Jocqué, Rudy; Palmer, Todd M

2010-05-25

The finding that regular spatial patterns can emerge in nature from local interactions between organisms has prompted a search for the ecological importance of these patterns. Theoretical models have predicted that patterning may have positive emergent effects on fundamental ecosystem functions, such as productivity. We provide empirical support for this prediction. In dryland ecosystems, termite mounds are often hotspots of plant growth (primary productivity). Using detailed observations and manipulative experiments in an African savanna, we show that these mounds are also local hotspots of animal abundance (secondary and tertiary productivity): insect abundance and biomass decreased with distance from the nearest termite mound, as did the abundance, biomass, and reproductive output of insect-eating predators. Null-model analyses indicated that at the landscape scale, the evenly spaced distribution of termite mounds produced dramatically greater abundance, biomass, and reproductive output of consumers across trophic levels than would be obtained in landscapes with randomly distributed mounds. These emergent properties of spatial pattern arose because the average distance from an arbitrarily chosen point to the nearest feature in a landscape is minimized in landscapes where the features are hyper-dispersed (i.e., uniformly spaced). This suggests that the linkage between patterning and ecosystem functioning will be common to systems spanning the range of human management intensities. The centrality of spatial pattern to system-wide biomass accumulation underscores the need to conserve pattern-generating organisms and mechanisms, and to incorporate landscape patterning in efforts to restore degraded habitats and maximize the delivery of ecosystem services.

Relative role of contemporary environment versus history in shaping diversity patterns of China's woody plants

DEFF Research Database (Denmark)

Wang, Zhiheng; Fang, Jingyun; Tang, Zhiyao

2012-01-01

What determines large-scale patterns of species diversity is a central and controversial topic in biogeography and ecology. In this study, we compared the effects of contemporary environment and historical contingencies on species richness patterns of woody plants in China, using fine-resolution ......-plant species richness across China, while historical contingencies generate regional deviations from this trend. Our findings imply that both species diversity and regional evolutionary and ecological histories should be taken into account for future nature conservation......., and the Tibetan Plateau, perhaps reflecting their special geological features and history. Nevertheless, partial regression indicated that historical effects were less important relative to contemporary environment. In conclusion, contemporary environment (notably climate) determines the general trend in woody...

Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

Science.gov (United States)

Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

2010-08-01

High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that the pattern is complex, representing two constructional generations of dunes. The oldest and best-organized generation forms the primary crestlines and is transverse to circumpolar easterly winds. Gross bed form-normal analysis of the younger pattern of crestlines indicates that it emerged with both circumpolar easterly winds and NE winds and is reworking the older pattern. Mapping of secondary flow fields over the dunes indicates that the most recent transporting winds were from the NE. The younger pattern appears to represent an influx of sediment to the dune field associated with the development of the Olympia Cavi reentrant, with NE katabatic winds channeling through the reentrant. A model of the pattern reformation based upon the reconstructed primary winds and resulting secondary flow fields shows that the development of the secondary pattern is controlled by the boundary condition of the older dune topography.

Three invariant Hi-C interaction patterns: Applications to genome assembly.

Science.gov (United States)

Oddes, Sivan; Zelig, Aviv; Kaplan, Noam

2018-06-01

Assembly of reference-quality genomes from next-generation sequencing data is a key challenge in genomics. Recently, we and others have shown that Hi-C data can be used to address several outstanding challenges in the field of genome assembly. This principle has since been developed in academia and industry, and has been used in the assembly of several major genomes. In this paper, we explore the central principles underlying Hi-C-based assembly approaches, by quantitatively defining and characterizing three invariant Hi-C interaction patterns on which these approaches can build: Intrachromosomal interaction enrichment, distance-dependent interaction decay and local interaction smoothness. Specifically, we evaluate to what degree each invariant pattern holds on a single locus level in different species, cell types and Hi-C map resolutions. We find that these patterns are generally consistent across species and cell types but are affected by sequencing depth, and that matrix balancing improves consistency of loci with all three invariant patterns. Finally, we overview current Hi-C-based assembly approaches in light of these invariant patterns and demonstrate how local interaction smoothness can be used to easily detect scaffolding errors in extremely sparse Hi-C maps. We suggest that simultaneously considering all three invariant patterns may lead to better Hi-C-based genome assembly methods. Copyright © 2018 Elsevier Inc. All rights reserved.

The Aeolian Asynchronous Generator

Directory of Open Access Journals (Sweden)

Ionel Dragomirescu

2008-10-01

Full Text Available The production of the electric energy with lower costs could be realized with the help of the aeolian electric central. In these centrals we can use the squirrel cage asynchronous generators, because these machines are the most safety in function and easy exploited. This work show the function analyzing of the asynchronous generator having on involving torque depending on the square wind speed, the air-density and on the construction of the wing spiral.

What Is Web 2.0: Design Patterns and Business Models for the Next Generation of Software

OpenAIRE

O'Reilly, Tim

2007-01-01

This paper was the first initiative to try to define Web2.0 and understand its implications for the next generation of software, looking at both design patterns and business modes. Web 2.0 is the network as platform, spanning all connected devices; Web 2.0 applications are those that make the most of the intrinsic advantages of that platform: delivering software as a continually-updated service that gets better the more people use it, consuming and remixing data from multiple sources, includi...

Patterns of mast fruiting of common beech, sessile and common oak, Norway spruce and Scots pine in Central and Northern Europe

DEFF Research Database (Denmark)

Nussbaumer, Anita; Waldner, Peter; Etzold, Sophia

2016-01-01

Occurrence of mast years, i.e. the synchronous production of vast amounts of fruits or seeds, has an important impact on forest ecosystems, their functioning and their services. We investigated the mast patterns of the forest tree species common beech, common and sessile oak, Norway spruce...... and Scots pine in Central and Northern Europe over the last two to three decades. We analysed data from the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) and additional Danish, German, Flemish and Swiss datasets.Within-plot synchrony...

Precipitation regimes over central Greenland inferred from 5 years of ICECAPS observations

Science.gov (United States)

Pettersen, Claire; Bennartz, Ralf; Merrelli, Aronne J.; Shupe, Matthew D.; Turner, David D.; Walden, Von P.

2018-04-01

A novel method for classifying Arctic precipitation using ground based remote sensors is presented. Using differences in the spectral variation of microwave absorption and scattering properties of cloud liquid water and ice, this method can distinguish between different types of snowfall events depending on the presence or absence of condensed liquid water in the clouds that generate the precipitation. The classification reveals two distinct, primary regimes of precipitation over the Greenland Ice Sheet (GIS): one originating from fully glaciated ice clouds and the other from mixed-phase clouds. Five years of co-located, multi-instrument data from the Integrated Characterization of Energy, Clouds, Atmospheric state, and Precipitation at Summit (ICECAPS) are used to examine cloud and meteorological properties and patterns associated with each precipitation regime. The occurrence and accumulation of the precipitation regimes are identified and quantified. Cloud and precipitation observations from additional ICECAPS instruments illustrate distinct characteristics for each regime. Additionally, reanalysis products and back-trajectory analysis show different synoptic-scale forcings associated with each regime. Precipitation over the central GIS exhibits unique microphysical characteristics due to the high surface elevations as well as connections to specific large-scale flow patterns. Snowfall originating from the ice clouds is coupled to deep, frontal cloud systems advecting up and over the southeast Greenland coast to the central GIS. These events appear to be associated with individual storm systems generated by low pressure over Baffin Bay and Greenland lee cyclogenesis. Snowfall originating from mixed-phase clouds is shallower and has characteristics typical of supercooled cloud liquid water layers, and slowly propagates from the south and southwest of Greenland along a quiescent flow above the GIS.

Spatial patterns in Central Asian climate and equilibrium line altitudes

International Nuclear Information System (INIS)

Rupper, Summer; Koppes, Michele

2010-01-01

A suite of general circulation model (GCM) simulations and a glacier equilibrium line altitude (ELA) model are compared to reconstructed glacier advances from geomorphic data and used to test the sensitivity of Central Asian glaciers to simulated climate changes at the Last Glacial Maximum (LGM). Results highlight temperature changes as being the most important influence on glacier ELA changes during the LGM. With the exception of the southern Himalaya, for much of Central Asia there is consistency between GCMs for simulated LGM temperature changes, with a mean cooling of 4 0 C. Further research will necessarily need to focus on detailed analysis of the inter-model differences in temperature in the southern Himalaya, and acquiring additional paleoclimate proxies in the region in order to further constrain the GCMs.

Metameric pattern of intervertebral disc/vertebral body is generated independently of Mesp2/Ripply-mediated rostro-caudal patterning of somites in the mouse embryo.

Science.gov (United States)

Takahashi, Yu; Yasuhiko, Yukuto; Takahashi, Jun; Takada, Shinji; Johnson, Randy L; Saga, Yumiko; Kanno, Jun

2013-08-15

The vertebrae are derived from the sclerotome of somites. Formation of the vertebral body involves a process called resegmentation, by which the caudal half of a sclerotome is combined with the rostral half of the next sclerotome. To elucidate the relationship between resegmentation and rostro-caudal patterning of somite, we used the Uncx4.1-LacZ transgene to characterize the resegmentation process. Our observations suggested that in the thoracic and lumbar vertebrae, the Uncx4.1-expressing caudal sclerotome gave rise to the intervertebral disc (IVD) and rostral portion of the vertebral body (VB). In the cervical vertebrae, the Uncx4.1-expressing caudal sclerotome appeared to contribute to the IVD and both caudal and rostral ends of the VB. This finding suggests that the rostro-caudal gene expression boundary does not necessarily coincide with the resegmentation boundary. This conclusion was supported by analyses of Mesp2 KO and Ripply1/2 double KO embryos lacking rostral and caudal properties, respectively. Resegmentation was not observed in Mesp2 KO embryos, but both the IVD and whole VB were formed from the caudalized sclerotome. Expression analysis of IVD marker genes including Pax1 in the wild-type, Mesp2 KO, and Ripply1/2 DKO embryos also supported the idea that a metameric pattern of IVD/VB is generated independently of Mesp2/Ripply-mediated rostro-caudal patterning of somite. However, in the lumbar region, IVD differentiation appeared to be stimulated by the caudal property and suppressed by the rostral property. Therefore, we propose that rostro-caudal patterning of somites is not a prerequisite for metameric patterning of the IVD and VB, but instead required to stimulate IVD differentiation in the caudal half of the sclerotome. Copyright © 2013 Elsevier Inc. All rights reserved.

Least-cost network evaluation of centralized and decentralized contributions to global electrification

International Nuclear Information System (INIS)

Levin, Todd; Thomas, Valerie M.

2012-01-01

The choice between centralized and decentralized electricity generation is examined for 150 countries as a function of population distribution, electricity consumption, transmission cost, and the cost difference between decentralized and centralized electricity generation. A network algorithm is developed to find the shortest centralized transmission network that spans a given fraction of the population in a country. The least-cost combination of centralized and decentralized electricity that serves the country is determined. Case studies of Botswana, Uganda, and Bangladesh illustrate situations that are more and less suited for decentralized electrification. Specific maps for centralized and decentralized generation are presented to show how the least-cost option varies with the relative costs of centralized and decentralized generation and transmission cost. Centralized and decentralized fractions are calculated for 150 countries. For most of the world's population, centralized electricity is the least-cost option. For a number of countries, particularly in Africa, substantial populations and regions may be most cost-effectively served by decentralized electricity. - Highlights: ► Centralized and decentralized electrification are compared for 150 countries. ► A cost-optimized network algorithm finds the least-cost electrification system. ► Least-cost infrastructures combine centralized and decentralized portions. ► For most people, centralized electricity is cheapest option. ► In much of Africa, decentralized electricity may be cheaper than centralized.

Comparative assessment of agricultural technology generating practices in universities and research institutes in north central zone of Nigeria

Directory of Open Access Journals (Sweden)

Gbolagade Benjamin Adesiji

2017-06-01

Full Text Available To understand the technology generating practices among universities and research institutes in north central zone of Nigeria, this study examined sources of funds for technology generating activities, compared agro-technology generating practices and identified constraining factors hindering technology generating practices. One hundred and fifty-two academic staff were randomly selected from universities and one hundred and thirty-six respondents were drawn from research institutes. Validated questionnaires with reliability coefficient of r = 0.92 were used to elicit data. Data were analyzed using descriptive statistics, Likert-scale, T-test and Factor analysis. Majority (93.4% of universities’ respondents used their personal funds to generate new technology compared to their counterparts in research institutes. The most widely employed mechanism for generating agricultural technologies was joint radio programmes (mean = 3.38 while the least was biotechnology (mean = 2.57. Major areas of differences in technology generation between the two institutions were the physical distance (t = 13.54; P < 0.05, farmers participation in field research trials (t = 8.50; P < 0.05, farmers co-finance of adaptive research trials (t = 3.77; P < 0.05 and adequate research facilities and incentives to workers (t = 2.05; P < 0.05. Factors constraining technology generation for universities were poor access to knowledge and information on new innovation (r = 0.815 while for research institutes it was limited physical resources (ICT, Telephone (r = 0.801. It was recommended therefore that respondents should look into options of writing alternate fund proposals and submitting to a wider range of funding bodies. Governance of innovation could be strengthened through the formation of a formal technological linkage advisory council.

Fluid power network for centralized electricity generation in offshore wind farms

International Nuclear Information System (INIS)

Jarquin-Laguna, A

2014-01-01

An innovative and completely different wind-energy conversion system is studied where a centralized electricity generation within a wind farm is proposed by means of a hydraulic network. This paper presents the dynamic interaction of two turbines when they are coupled to the same hydraulic network. Due to the stochastic nature of the wind and wake interaction effects between turbines, the operating parameters (i.e. pitch angle, rotor speed) of each turbine are different. Time domain simulations, including the main turbine dynamics and laminar transient flow in pipelines, are used to evaluate the efficiency and rotor speed stability of the hydraulic system. It is shown that a passive control of the rotor speed, as proposed in previous work for a single hydraulic turbine, has strong limitations in terms of performance for more than one turbine coupled to the same hydraulic network. It is concluded that in order to connect several turbines, a passive control strategy of the rotor speed is not sufficient and a hydraulic network with constant pressure is suggested. However, a constant pressure network requires the addition of active control at the hydraulic motors and spear valves, increasing the complexity of the initial concept. Further work needs to be done to incorporate an active control strategy and evaluate the feasibility of the constant pressure hydraulic network

Fusion Kalman filtration with k-step delay sharing pattern

Directory of Open Access Journals (Sweden)

Duda Zdzisław

2015-09-01

Full Text Available A fusion hierarchical state filtration with k−step delay sharing pattern for a multisensor system is considered. A global state estimate depends on local state estimates determined by local nodes using local information. Local available information consists of local measurements and k−step delay global information - global estimate sent from a central node. Local estimates are transmitted to the central node to be fused. The synthesis of local and global filters is presented. It is shown that a fusion filtration with k−step delay sharing pattern is equivalent to the optimal centralized classical Kalman filtration when local measurements are transmitted to the center node and used to determine a global state estimate. It is proved that the k−step delay sharing pattern can reduce covariances of local state errors.

Four integration patterns

DEFF Research Database (Denmark)

Bygstad, Bendik; Nielsen, Peter Axel; Munkvold, Bjørn Erik

2010-01-01

This paper aims to contribute to a theory of integration within the field of IS project management. Integration is a key IS project management issue when new systems are developed and implemented into an increasingly integrated information infrastructure in corporate and governmental organizations....... Expanding the perspective of traditional project management research, we draw extensively on central insights from IS research. Building on socio-technical IS research and Software Engineering research we suggest four generic patterns of integration: Big Bang, Stakeholder Integration, Technical Integration...... and Socio-Technical Integration. We analyze and describe the advantages and disadvantages of each pattern. The four patterns are ideal types. To explore the forces and challenges in these patterns three longitudinal case studies were conducted. In particular we investigate the management challenges for each...

Erosividade e padrões hidrológicos de precipitação no Agreste Central pernambucano Erosivity and rainfall hydrological patterns in the Pernambuco Central 'Agreste'

Directory of Open Access Journals (Sweden)

Thais E. M. dos Santos

2012-08-01

Full Text Available A principal forma de erosão nas condições brasileiras é a causada pela energia cinética do impacto das gotas de chuva sobre a superfície do solo, desencadeando o processo de erosão hídrica. Desenvolveu-se o presente trabalho com o objetivo de avaliar o índice de erosividade (EI30 e caracterizar o padrão hidrológico das chuvas do Agreste Central pernambucano, considerando-se uma série de 29 anos de dados, ficando patente que o primeiro semestre do ano é caracterizado pela ocorrência de chuvas de elevado potencial erosivo. O valor do fator "R" da equação universal de perda de solo para a região estudada é de 2.779,79 MJ mm ha-1 h-1. O padrão de chuva de maior ocorrência é o avançado, seguido do intermediário e atrasado, com 46,57; 36,38 e 17,19% dos totais de chuvas erosivas analisados, respectivamente. Não foram encontradas correlações significativas entre erosividade, coeficiente de chuva e precipitação.The main form of erosion in Brazilian conditions is caused by the kinetic energy of the impact of raindrops on the soil surface, triggering the erosion process. The present study was conducted with the aim to evaluate the erosivity index (EI30, as well as to characterize the hydrological pattern of rainfall in the Pernambuco Central 'Agreste', considering a series of 29 years of data. It was found that the first half of the year is characterized by rain with high erosive potential. The value of the factor "R" in the Universal equation of soil loss for the studied region is 2,779.79 MJ mm ha-1 h-1. The rain pattern of higher occurrence is the advanced, followed by intermediate and delayed, with 46.57; 36.38 and 17.19% of total erosive rainfall analyzed, respectively. There were no significant correlations between erosivity, rainfall coefficient and precipitation.

Spatiotemporal patterns of the fossil-fuel CO2 signal in central Europe: results from a high-resolution atmospheric transport model

Science.gov (United States)

Liu, Yu; Gruber, Nicolas; Brunner, Dominik

2017-11-01

The emission of CO2 from the burning of fossil fuel is a prime determinant of variations in atmospheric CO2. Here, we simulate this fossil-fuel signal together with the natural and background components with a regional high-resolution atmospheric transport model for central and southern Europe considering separately the emissions from different sectors and countries on the basis of emission inventories and hourly emission time functions. The simulated variations in atmospheric CO2 agree very well with observation-based estimates, although the observed variance is slightly underestimated, particularly for the fossil-fuel component. Despite relatively rapid atmospheric mixing, the simulated fossil-fuel signal reveals distinct annual mean structures deep into the troposphere, reflecting the spatially dense aggregation of most emissions. The fossil-fuel signal accounts for more than half of the total (fossil fuel + biospheric + background) temporal variations in atmospheric CO2 in most areas of northern and western central Europe, with the largest variations occurring on diurnal timescales owing to the combination of diurnal variations in emissions and atmospheric mixing and transport out of the surface layer. The covariance of the fossil-fuel emissions and atmospheric transport on diurnal timescales leads to a diurnal fossil-fuel rectifier effect of up to 9 ppm compared to a case with time-constant emissions. The spatial pattern of CO2 from the different sectors largely reflects the distribution and relative magnitude of the corresponding emissions, with power plant emissions leaving the most distinguished mark. An exception is southern and western Europe, where the emissions from the transportation sector dominate the fossil-fuel signal. Most of the fossil-fuel CO2 remains within the country responsible for the emission, although in smaller countries up to 80 % of the fossil-fuel signal can come from abroad. A fossil-fuel emission reduction of 30 % is clearly

The Staffing of Central Electricity Generating Board Nuclear Power Stations; Organigramme des centrales nucleaires du central electricity generating board; Politika v oblasti kadrov na atomnykh ehlektrostantsiyakh CEGB; El personal de las plantas nucleoelectricas de la central electricity generating board.

Energy Technology Data Exchange (ETDEWEB)

Bartlett, J. S.; Shepherd, G. T. [Central Electricity Generating Board, Western Division, Bristol (United Kingdom)

1963-10-15

An account is given of the staffing requirements and organization at a CEBG nuclear power station. The training of staff and licensing requirements for reactoroperating staff are discussed. Experience gained to data of the outcome of pre-operating training and detailed planning in the operational sphere is given. (author) [French] Le memoire donne un apercu de l'organigramme d'une centrale nucleaire du CEGB et des conditions auxquelles doit satisfaire le personnel (formation, qualifications requises pour la fonction d'operateur). Il rend compte egalement de l'experience acquise a ce jour quant a l'interet qu'il y a a former le personnel au prealable et a etablir des plans d'operation detailles. (author) [Spanish] La memoria informa sobre la organizacion de las centrales nucleoelectricas de la CEGB y sobre la plantilla de personal que estas requieren. Discute la formacion del personal y los requisitos para obtener la licencia de operador de reactores. Describe la experiencia adquirida hasta el presente en materia de formacion previa del personal y de organizacion detallada de las operaciones. (author) [Russian] Daetsya otchet o trebovaniyakh, pred{sup y}avlyaemykh k personalu, i organizatsiya nabora personala na atomnykh ehlektrostantsiyakh Tsentral'nogo upravleniya proizvodstva ehlektroehnergii (CEGB). Obsuzhdayutsya voprosy podgotovki personala i normativnykh trebovanij, pred{sup y}avlyaemykh k ehkspluatatsionnomu personalu. Izlagaetsya opyt, nakoplennyj k nastoyashchemu vremeni v rezul'tate osushchestvleniya predehkspluatatsionnoj podgotovki i podrobnogo planirovaniya v usloviyakh ehkspluatatsii. (author)

Controlling centrality in complex networks

Science.gov (United States)

Nicosia, V.; Criado, R.; Romance, M.; Russo, G.; Latora, V.

2012-01-01

Spectral centrality measures allow to identify influential individuals in social groups, to rank Web pages by popularity, and even to determine the impact of scientific researches. The centrality score of a node within a network crucially depends on the entire pattern of connections, so that the usual approach is to compute node centralities once the network structure is assigned. We face here with the inverse problem, that is, we study how to modify the centrality scores of the nodes by acting on the structure of a given network. We show that there exist particular subsets of nodes, called controlling sets, which can assign any prescribed set of centrality values to all the nodes of a graph, by cooperatively tuning the weights of their out-going links. We found that many large networks from the real world have surprisingly small controlling sets, containing even less than 5 – 10% of the nodes. PMID:22355732

Investigation of patterned and non-patterned poly(2,6-dimethyl 1,4-phenylene) oxide based anion exchange membranes for enhanced desalination and power generation in a microbial desalination cell.

Science.gov (United States)

Moruno, Francisco Lopez; Rubio, Juan E; Santoro, Carlo; Atanassov, Plamen; Cerrato, José M; Arges, Christopher G

2018-01-01

Quaternary ammonium poly(2,6-dimethyl 1,4-phenylene oxide) (QAPPO) anion exchange membranes (AEMs) with topographically patterned surfaces were assessed in a microbial desalination cell (MDC) system. The MDC results with these QAPPO AEMs were benchmarked against a commercially available AEM. The MDC with the non-patterned QAPPO AEM (Q1) displayed the best desalination rate (a reduction of salinity by 53 ± 2.7%) and power generation (189 ± 5 mW m - 2 ) when compared against the commercially available AEM and the patterned AEMs. The enhanced performance with the Q1 AEM was attributed to its higher ionic conductivity and smaller thickness leading to a reduced area specific resistance. It is important to note that Real Pacific Ocean seawater and activated sludge were used into the desalination chamber and anode chamber respectively for the MDC - which mimicked realistic conditions. Although the non-patterned QAPPO AEM displayed better performance over the patterned QAPPO AEMs, it was observed that the anodic overpotential was smaller when the MDCs featured QAPPO AEMs with larger lateral feature sizes. The results from this study have important implications for the continuous improvements necessary for developing cheaper and better performing membranes in order to optimize the MDC.

Rice agriculture impacts catchment hydrographic patterns and nitrogen export characteristics in subtropical central China: a paired-catchment study.

Science.gov (United States)

Wang, Yi; Liu, Xinliang; Wang, Hua; Li, Yong; Li, Yuyuan; Liu, Feng; Xiao, Runlin; Shen, Jianlin; Wu, Jinshui

2017-06-01

Increased nitrogen (N) concentrations in water bodies have highlighted issues regarding nutrient pollution in agricultural catchments. In this study, the ammonium-N (NH 4 + -N), nitrate-N (NO 3 - -N), and total N (TN) concentrations were observed in the stream water and groundwater of two contrasting catchments (named Tuojia and Jianshan) in subtropical central China from 2010 to 2014, to determine the rice agriculture impacts on the hydrographic patterns, and N export characteristics of the catchments. The results suggested that greater amounts of stream flow (523.0 vs. 434.7 mm year -1 ) and base flow (237.6 vs. 142.8 mm year -1 ) were produced in Tuojia than in Jianshan, and a greater base flow contribution to stream flow and higher frequencies of high-base flow days were observed during the fallow season than during the rice-growing season, indicating that intensive rice agriculture strongly influences the catchment hydrographic pattern. Rice agriculture resulted in moderate N pollution in the stream water and groundwater, particularly in Tuojia. Primarily, rice agriculture increased the NH 4 + -N concentration in the stream water; however, it increased the NO 3 - -N concentrations in the groundwater, suggesting that the different N species in the paddy fields migrated out of the catchments through distinct hydrological pathways. The average TN loading via stream flow and base flow was greater in Tuojia than in Jianshan (1.72 and 0.58 vs. 0.72 and 0.15 kg N ha -1  month -1 , respectively). Greater TN loading via stream flow was observed during the fallow season in Tuojia and during the rice-growing season in Jianshan, and these different results were most likely a result of the higher base flow contribution to TN loading (33.5 vs. 21.3%) and greater base flow enrichment ratio (1.062 vs. 0.876) in Tuojia than in Jianshan. Therefore, the impact of rice agriculture on catchment eco-hydrological processes should be considered when performing water quality

Identify the consumption patterns of the second generation Chinese middle class. Does culture influence their consumption habits?

OpenAIRE

Liu, Kim Man

2012-01-01

Background: The 1978 political social reform in China has led to the emergence of the rapid and fast growing urban ‘middle class’ population. With the rise of the large population of middle class consumers, global market developers and opportunists are targeting this group of people to maximize their profits in developing countries. This research aimed to identify the consumption patterns of the second generation Chinese middle class and to investigate if their unique Chinese culture influenc...

Comparison of Patterns of Use of Unrecorded and Recorded Spirits: Survey of Adult Drinkers in Rural Central China

Directory of Open Access Journals (Sweden)

Shiqing Wei

2017-09-01

Full Text Available About 70% of the beverage alcohol consumed in China annually is spirits. Recorded spirits make up most spirit consumption, but about 25% of total alcohol consumption (1.7 L pure alcohol per capita annually is unrecorded spirits (bai jiu, either homemade or made in unregulated distilleries. In some parts of China, the consumption of unrecorded spirits is higher than average. This paper compares the patterns of use of unrecorded distilled spirits and recorded distilled spirits among rural residents in Central China. Interviews were conducted with 3298 individuals in 21 towns/villages in 10 counties in the Hubei, Anhui, and Hebei provinces in the People’s Republic of China. Unrecorded bai jiu drinkers chose it because of its taste and its low price. It was consumed mostly by older men, mostly at home with family, more regularly and at higher alcohol by volume (ABV compared to recorded alcohol. Recorded bai jiu drinkers were more likely to drink away from their homes, consumed more bai jiu at memorable drinking occasions, and reported feeling sick after drinking more often than unrecorded bai jiu drinkers. This comparison of patterns of use of unrecorded bai jiu and recorded bai jiu does not suggest that unrecorded bai jiu is more problematic for drinkers.

Comparison of Patterns of Use of Unrecorded and Recorded Spirits: Survey of Adult Drinkers in Rural Central China.

Science.gov (United States)

Wei, Shiqing; Yin, Ping; Newman, Ian M; Qian, Ling; Shell, Duane F; Yuen, Lok-Wa

2017-09-22

About 70% of the beverage alcohol consumed in China annually is spirits. Recorded spirits make up most spirit consumption, but about 25% of total alcohol consumption (1.7 L pure alcohol per capita annually) is unrecorded spirits (bai jiu), either homemade or made in unregulated distilleries. In some parts of China, the consumption of unrecorded spirits is higher than average. This paper compares the patterns of use of unrecorded distilled spirits and recorded distilled spirits among rural residents in Central China. Interviews were conducted with 3298 individuals in 21 towns/villages in 10 counties in the Hubei, Anhui, and Hebei provinces in the People's Republic of China. Unrecorded bai jiu drinkers chose it because of its taste and its low price. It was consumed mostly by older men, mostly at home with family, more regularly and at higher alcohol by volume (ABV) compared to recorded alcohol. Recorded bai jiu drinkers were more likely to drink away from their homes, consumed more bai jiu at memorable drinking occasions, and reported feeling sick after drinking more often than unrecorded bai jiu drinkers. This comparison of patterns of use of unrecorded bai jiu and recorded bai jiu does not suggest that unrecorded bai jiu is more problematic for drinkers.

Second-Generation central venous catheter in the prevention of bloodstream infection: a systematic review.

Science.gov (United States)

Stocco, Janislei Gislei Dorociaki; Hoers, Hellen; Pott, Franciele Soares; Crozeta, Karla; Barbosa, Dulce Aparecida; Meier, Marineli Joaquim

2016-08-08

to evaluate the effectiveness and safety in the use of second-generation central venous catheters impregnated in clorhexidine and silver sulfadiazine when compared with other catheters, being them impregnated or not, in order to prevent the bloodstream infection prevention. systematic review with meta-analysis. Databases searched: MEDLINE, EMBASE, CINAHL, LILACS/SciELO, Cochrane CENTRAL; search in Congress Proceedings and records from Clinical Trials. 1.235 studies were identified, 97 were pre-selected and 4 were included. In catheter-related bloodstream infection, there was no statistical significance between second-generation impregnated catheter compared with the non-impregnated ones, absolute relative risk 1,5% confidence interval 95% (3%-1%), relative risk 0,68 (confidence interval 95%, 0,40-1,15) and number needed to treat 66. In the sensitivity analysis, there was less bloodstream infection in impregnated catheters (relative risk 0,50, confidence interval 95%, 0,26-0,96). Lower colonization, absolute relative risk 9,6% (confidence interval 95%, 10% to 4%), relative risk 0,51 (confidence interval 95% from 0,38-0,85) and number needed to treat 5. the use of second-generation catheters was effective in reducing the catheter colonization and infection when a sensitivity analysis is performed. Future clinical trials are suggested to evaluate sepsis rates, mortality and adverse effects. evaluar la efectividad y seguridad del uso de catéteres venosos centrales de segunda generación, impregnados en clorhexidina y sulfadiazina de plata, comparados con otros catéteres impregnados o no impregnados, para prevención de infección de la corriente sanguínea. revisión sistemática con metaanálisis. La búsqueda fue realizada en las bases: MEDLINE, EMBASE, CINAHL, LILACS/SciELO, Cochrane CENTRAL; fueron consultados anales de congresos y registros de ensayos clínicos. fueron identificados 1.235 estudios, 97 preseleccionados y cuatro incluidos. En la infección de la

Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data.

Science.gov (United States)

Nuel, Gregory; Regad, Leslie; Martin, Juliette; Camproux, Anne-Claude

2010-01-26

In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.). Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models. The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence. Our algorithms prove to be effective and able to handle real data sets with multiple sequences, as well as biological patterns of

Evaluating Cancer of the Central Nervous System Through Next-Generation Sequencing of Cerebrospinal Fluid

Science.gov (United States)

Pentsova, Elena I.; Shah, Ronak H.; Tang, Jiabin; Boire, Adrienne; You, Daoqi; Briggs, Samuel; Omuro, Antonio; Lin, Xuling; Fleisher, Martin; Grommes, Christian; Panageas, Katherine S.; Meng, Fanli; Selcuklu, S. Duygu; Ogilvie, Shahiba; Distefano, Natalie; Shagabayeva, Larisa; Rosenblum, Marc; DeAngelis, Lisa M.; Viale, Agnes; Berger, Michael F.

2016-01-01

Purpose Cancer spread to the central nervous system (CNS) often is diagnosed late and is unresponsive to therapy. Mechanisms of tumor dissemination and evolution within the CNS are largely unknown because of limited access to tumor tissue. Materials and Methods We sequenced 341 cancer-associated genes in cell-free DNA from cerebrospinal fluid (CSF) obtained through routine lumbar puncture in 53 patients with suspected or known CNS involvement by cancer. Results We detected high-confidence somatic alterations in 63% (20 of 32) of patients with CNS metastases of solid tumors, 50% (six of 12) of patients with primary brain tumors, and 0% (zero of nine) of patients without CNS involvement by cancer. Several patients with tumor progression in the CNS during therapy with inhibitors of oncogenic kinases harbored mutations in the kinase target or kinase bypass pathways. In patients with glioma, the most common malignant primary brain tumor in adults, examination of cell-free DNA uncovered patterns of tumor evolution, including temozolomide-associated mutations. Conclusion The study shows that CSF harbors clinically relevant genomic alterations in patients with CNS cancers and should be considered for liquid biopsies to monitor tumor evolution in the CNS. PMID:27161972

Integration of Descending Command Systems for the Generation of Context-Specific Locomotor Behaviors

Directory of Open Access Journals (Sweden)

Linda H. Kim

2017-10-01

Full Text Available Over the past decade there has been a renaissance in our understanding of spinal cord circuits; new technologies are beginning to provide key insights into descending circuits which project onto spinal cord central pattern generators. By integrating work from both the locomotor and animal behavioral fields, we can now examine context-specific control of locomotion, with an emphasis on descending modulation arising from various regions of the brainstem. Here we examine approach and avoidance behaviors and the circuits that lead to the production and arrest of locomotion.

Motoneurons have different membrane resistance during fictive scratching and weight support

DEFF Research Database (Denmark)

Perreault, Marie-Claude

2002-01-01

locomotion; central pattern generator; spinal cord; synaptic integration; membrane conductance; glycine; postsynaptic inhibition; chloride......locomotion; central pattern generator; spinal cord; synaptic integration; membrane conductance; glycine; postsynaptic inhibition; chloride...

Ecological networks and nature policy in central Russia : peat bogs in central and northern Meshera

NARCIS (Netherlands)

Butovsky, R.O.; Reijnen, R.; Otchagov, D.M.; Aleshenko, G.M.; Melik-Bagdasarov, E.

2001-01-01

In central and northern Meshera, Russia, the habitat of many characteristic peat bog species now show a very fragmented pattern. Peat mining and other human influences are the most important causes. As a result the potentials for viable populations ofcharacteristic peat bog species have decreased

Paleoclimate determines diversification patterns in the fossorial snake family Uropeltidae Cuvier, 1829.

Science.gov (United States)

Cyriac, Vivek Philip; Kodandaramaiah, Ullasa

2017-11-01

Understanding how and why diversification rates vary across evolutionary time is central to understanding how biodiversity is generated and maintained. Recent mathematical models that allow estimation of diversification rates across time from reconstructed phylogenies have enabled us to make inferences on how biodiversity copes with environmental change. Here, we explore patterns of temporal diversification in Uropeltidae, a diverse fossorial snake family. We generate a time-calibrated phylogenetic hypothesis for Uropeltidae and show a significant correlation between diversification rate and paleotemperature during the Cenozoic. We show that the temporal diversification pattern of this group is punctuated by one rate shift event with a decrease in diversification and turnover rate between ca. 11Ma to present, but there is no strong support for mass extinction events. The analysis indicates higher turnover during periods of drastic climatic fluctuations and reduced diversification rates associated with contraction and fragmentation of forest habitats during the late Miocene. Our study highlights the influence of environmental fluctuations on diversification rates in fossorial taxa such as uropeltids, and raises conservation concerns related to present rate of climate change. Copyright © 2017 Elsevier Inc. All rights reserved.

Generation of predictive price and trading volume patterns in a model of dynamically evolving free market supply and demand

Directory of Open Access Journals (Sweden)

J. K. Wang

2001-01-01

Full Text Available I present a model of stock market price fluctuations incorporating effects of share supply as a history-dependent function of previous purchases and share demand as a function of price deviation from moving averages. Price charts generated show intervals of oscillations switching amplitude and frequency suddenly in time, forming price and trading volume patterns well-known in market technical analysis. Ultimate price trends agree with traditional predictions for specific patterns. The consideration of dynamically evolving supply and demand in this model resolves the apparent contradiction with the Efficient Market Hypothesis: perceptions of imprecise equity values by a world of investors evolve over non-negligible periods of time, with dependence on price history.

On data processing required to derive mobility patterns from passively-generated mobile phone data

Science.gov (United States)

Wang, Feilong; Chen, Cynthia

2018-01-01

Passively-generated mobile phone data is emerging as a potential data source for transportation research and applications. Despite the large amount of studies based on the mobile phone data, only a few have reported the properties of such data, and documented how they have processed the data. In this paper, we describe two types of common mobile phone data: Call Details Record (CDR) data and sightings data, and propose a data processing framework and the associated algorithms to address two key issues associated with the sightings data: locational uncertainty and oscillation. We show the effectiveness of our proposed methods in addressing these two issues compared to the state of art algorithms in the field. We also demonstrate that without proper processing applied to the data, the statistical regularity of human mobility patterns—a key, significant trait identified for human mobility—is over-estimated. We hope this study will stimulate more studies in examining the properties of such data and developing methods to address them. Though not as glamorous as those directly deriving insights on mobility patterns (such as statistical regularity), understanding properties of such data and developing methods to address them is a fundamental research topic on which important insights are derived on mobility patterns. PMID:29398790

Impact of Thermal Plumes Generated by Occupant Simulators with Different Complexity of Body Geometry on Airflow Pattern in Rooms

DEFF Research Database (Denmark)

Zukowska, Daria; Melikov, Arsen Krikor; Popiolek, Zbigniew

2008-01-01

The impact of thermal plumes generated by human body simulators with different geometry on the airflow pattern in a full scale room with displacement ventilation (supply air temperature 21.6°C, total flow rate 80 L/s) was studied when two seated occupants were simulated first by two thermal...... manikins resembling accurately human body shape and then by two heated cylinders. The manikins and the cylinders had the same surface area of 1.63 m2 and the same heat generation of 73 W. CO2 supplied from the top of the heat sources was used for simulating bio-effluents. CO2 concentration was measured...

Automated Learning of Subcellular Variation among Punctate Protein Patterns and a Generative Model of Their Relation to Microtubules.

Directory of Open Access Journals (Sweden)

Gregory R Johnson

2015-12-01

Full Text Available Characterizing the spatial distribution of proteins directly from microscopy images is a difficult problem with numerous applications in cell biology (e.g. identifying motor-related proteins and clinical research (e.g. identification of cancer biomarkers. Here we describe the design of a system that provides automated analysis of punctate protein patterns in microscope images, including quantification of their relationships to microtubules. We constructed the system using confocal immunofluorescence microscopy images from the Human Protein Atlas project for 11 punctate proteins in three cultured cell lines. These proteins have previously been characterized as being primarily located in punctate structures, but their images had all been annotated by visual examination as being simply "vesicular". We were able to show that these patterns could be distinguished from each other with high accuracy, and we were able to assign to one of these subclasses hundreds of proteins whose subcellular localization had not previously been well defined. In addition to providing these novel annotations, we built a generative approach to modeling of punctate distributions that captures the essential characteristics of the distinct patterns. Such models are expected to be valuable for representing and summarizing each pattern and for constructing systems biology simulations of cell behaviors.

Transcriptome-wide patterns of divergence during allopatric evolution.

Science.gov (United States)

Pereira, Ricardo J; Barreto, Felipe S; Pierce, N Tessa; Carneiro, Miguel; Burton, Ronald S

2016-04-01

Recent studies have revealed repeated patterns of genomic divergence associated with species formation. Such patterns suggest that natural selection tends to target a set of available genes, but is also indicative that closely related taxa share evolutionary constraints that limit genetic variability. Studying patterns of genomic divergence among populations within the same species may shed light on the underlying evolutionary processes. Here, we examine transcriptome-wide divergence and polymorphism in the marine copepod Tigriopus californicus, a species where allopatric evolution has led to replicate sets of populations with varying degrees of divergence and hybrid incompatibility. Our analyses suggest that relatively small effective population sizes have resulted in an exponential decline of shared polymorphisms during population divergence and also facilitated the fixation of slightly deleterious mutations within allopatric populations. Five interpopulation comparisons at three different stages of divergence show that nonsynonymous mutations tend to accumulate in a specific set of proteins. These include proteins with central roles in cellular metabolism, such as those encoded in mtDNA, but also include an additional set of proteins that repeatedly show signatures of positive selection during allopatric divergence. Although our results are consistent with a contribution of nonadaptive processes, such as genetic drift and gene expression levels, generating repeatable patterns of genomic divergence in closely related taxa, they also indicate that adaptive evolution targeting a specific set of genes contributes to this pattern. Our results yield insights into the predictability of evolution at the gene level. © 2016 John Wiley & Sons Ltd.

Spatial Patterns of Species Diversity and Phylogenetic Structure of Plant Communities in the Tianshan Mountains, Arid Central Asia

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Hong-Xiang Zhang

2017-12-01

Full Text Available The Tianshan Mountains, located in arid Central Asia, have a humid climate and are biodiversity hotspots. Here, we aimed to clarify whether the pattern of species diversity and the phylogenetic structure of plant communities is affected by environmental variables and glacial refugia. In this study, plant community assemblies of 17 research sites with a total of 35 sample plots were investigated at the grassland/woodland boundaries on the Tianshan Mountains. Community phylogeny of these plant communities was constructed based on two plant DNA barcode regions. The indices of phylogenetic diversity and phylogenetic community structure were calculated for these sample plots. We first estimated the correlation coefficients between species richness (SR and environmental variables as well as the presence of glacial refugia. We then mapped the significant values of indices of community phylogeny (PD, RPD, NRI, and NTI to investigate the correlation between community phylogeny and environmental structure or macrozones in the study area. The results showed that a significantly higher value of SR was obtained for the refugial groups than for the colonizing groups (P < 0.05; presence of refugia and environmental variables were highly correlated to the pattern of variation in SR. Indices of community phylogeny were not significantly different between refugial and colonizing regions. Comparison with the humid western part showed that plant communities in the arid eastern part of the Tianshan Mountains tended to display more significant phylogenetic overdispersion. The variation tendency of the PhyloSor index showed that the increase in macro-geographical and environmental distance did not influence obvious phylogenetic dissimilarities between different sample plots. In conclusion, glacial refugia and environmental factors profoundly influenced the pattern of SR, but community phylogenetic structure was not affected by glacial refugia among different plant

Spatiotemporal Patterns of the Use of Urban Green Spaces and External Factors Contributing to Their Use in Central Beijing

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Fangzheng Li

2017-02-01

Full Text Available Urban green spaces encourage outdoor activity and social communication that contribute to the health of local residents. Examining the relationship between the use of urban green spaces and factors influencing their utilization can provide essential references for green space site selection in urban planning. In contrast to previous studies that focused on internal factors, this study highlights the external factors (traffic convenience, population density and commercial facilities contributing to the use of urban green spaces. We conducted a spatiotemporal analysis of the distribution of visitors in 208 selected green spaces in central Beijing. We examined the relationship between the spatial pattern of visitor distribution within urban green spaces and external factors, using the Gini coefficient, kernel density estimation, and geographical detectors. The results of the study were as follows. The spatial distribution of visitors within central Beijing’s green spaces was concentrated, forming different agglomerations. The three examined external factors are all associated with the use of green spaces. Among them, commercial facilities are the important external factor associated with the use of green spaces. For the selection of sites for urban green spaces, we recommend consideration of external factors in order to balance urban green space utilization.

Segmentation of turbo generator and reactor coolant pump vibratory patterns: a syntactic pattern recognition approach

International Nuclear Information System (INIS)

Tira, Z.

1993-02-01

This study was undertaken in the context of turbogenerator and reactor coolant pump vibration surveillance. Vibration meters are used to monitor equipment condition. An anomaly will modify the signal mean. At the present time, the expert system DIVA, developed to automate diagnosis, requests the operator to identify the nature of the pattern change thus indicated. In order to minimize operator intervention, we have to automate on the one hand classification and on the other hand, detection and segmentation of the patterns. The purpose of this study is to develop a new automatic system for the segmentation and classification of signals. The segmentation is based on syntactic pattern recognition. For the classification, a decision tree is used. The signals to process are the rms values of the vibrations measured on rotating machines. These signals are randomly sampled. All processing is automatic and no a priori statistical knowledge on the signals is required. The segmentation performances are assessed by tests on vibratory signals. (author). 31 figs

Assessing the conservation potential of damaged peat bog networks in Central and Northern Meshera (Central Russia)

NARCIS (Netherlands)

Butovsky, R.O.; Reijnen, M.J.S.M.; Aleshenko, G.M.; Melik-Bagdasarov, E.M.; Otchagov, D.M.

2004-01-01

Peat bogs are one of the most characteristic ecosystems of Central Russian landscape. Because of peat mining and transformation of peat bogs into agricultural land after drainage, suitable habitats for several characteristic species now show a very fragmented pattern. The potentials for viable

Distinguishing Computer-Generated Graphics from Natural Images Based on Sensor Pattern Noise and Deep Learning

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Ye Yao

2018-04-01

Full Text Available Computer-generated graphics (CGs are images generated by computer software. The rapid development of computer graphics technologies has made it easier to generate photorealistic computer graphics, and these graphics are quite difficult to distinguish from natural images (NIs with the naked eye. In this paper, we propose a method based on sensor pattern noise (SPN and deep learning to distinguish CGs from NIs. Before being fed into our convolutional neural network (CNN-based model, these images—CGs and NIs—are clipped into image patches. Furthermore, three high-pass filters (HPFs are used to remove low-frequency signals, which represent the image content. These filters are also used to reveal the residual signal as well as SPN introduced by the digital camera device. Different from the traditional methods of distinguishing CGs from NIs, the proposed method utilizes a five-layer CNN to classify the input image patches. Based on the classification results of the image patches, we deploy a majority vote scheme to obtain the classification results for the full-size images. The experiments have demonstrated that (1 the proposed method with three HPFs can achieve better results than that with only one HPF or no HPF and that (2 the proposed method with three HPFs achieves 100% accuracy, although the NIs undergo a JPEG compression with a quality factor of 75.

Steady-state exhumation pattern in the central Andes SE Peru

NARCIS (Netherlands)

Ruiz, G.M.H.; Carlotto, V.; van Heiningen, P.S.; Andriessen, P.A.M.

2009-01-01

The Western Cordillera of SE Peru is part of the Central Andes and is situated to the west of the Eastern Andes from which it is separated by the northern termination of the Altiplano - the Inter-Andean Valley. It is a volcanic-volcano-detrital chain that developed in the Palaeogene, and is

The importance of hydraulic architecture to the distribution patterns of trees in a central Amazonian forest.

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Cosme, Luiza H M; Schietti, Juliana; Costa, Flávia R C; Oliveira, Rafael S

2017-07-01

Species distributions and assemblage composition may be the result of trait selection through environmental filters. Here, we ask whether filtering of species at the local scale could be attributed to their hydraulic architectural traits, revealing the basis of hydrological microhabitat partitioning in a Central Amazonian forest. We analyzed the hydraulic characteristics at tissue (anatomical traits, wood specific gravity (WSG)), organ (leaf area, specific leaf area (SLA), leaf area : sapwood area ratio) and whole-plant (height) levels for 28 pairs of congeneric species from 14 genera restricted to either valleys or plateaus of a terra-firme forest in Central Amazonia. On plateaus, species had higher WSG, but lower mean vessel area, mean vessel hydraulic diameter, sapwood area and SLA than in valleys; traits commonly associated with hydraulic safety. Mean vessel hydraulic diameter and mean vessel area increased with height for both habitats, but leaf area and leaf area : sapwood area ratio investments with tree height declined in valley vs plateau species. [Correction added after online publication 29 March 2017: the preceding sentence has been reworded.] Two strategies for either efficiency or safety were detected, based on vessel size or allocation to sapwood. In conclusion, contrasting hydrological conditions act as environmental filters, generating differences in species composition at the local scale. This has important implications for the prediction of species distributions under future climate change scenarios. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Association and Centrality in Criminal Networks

DEFF Research Database (Denmark)

Petersen, Rasmus Rosenqvist

Network-based techniques are widely used in criminal investigations because patterns of association are actionable and understandable. Existing network models with nodes as first class entities and their related measures (e.g., social networks and centrality measures) are unable to capture...

Physiological modules for generating discrete and rhythmic movements: component analysis of EMG signals.

Science.gov (United States)

Bengoetxea, Ana; Leurs, Françoise; Hoellinger, Thomas; Cebolla, Ana Maria; Dan, Bernard; Cheron, Guy; McIntyre, Joseph

2014-01-01

A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the central nervous system (CNS) builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the generation of muscle activations when performing different types of movement: discrete, point-to-point movements in eight different directions and continuous figure-eight movements in both the normal, upright orientation and rotated 90°. To test for the effects of biomechanical constraints, movements were performed in the frontal-parallel or sagittal planes, corresponding to two different nominal flexion/abduction postures of the shoulder. In all cases we measured limb kinematics and surface electromyographic activity (EMG) signals for seven different muscles acting around the shoulder. We first performed principal component analysis (PCA) of the EMG signals on a movement-by-movement basis. We found a surprisingly consistent pattern of muscle groupings across movement types and movement planes, although we could detect systematic differences between the PCs derived from movements performed in each shoulder posture and between the principal components associated with the different orientations of the figure. Unexpectedly we found no systematic differences between the figure eights and the point-to-point movements. The first three principal components could be associated with a general co-contraction of all seven muscles plus two patterns of reciprocal activation. From these results, we surmise that both "discrete-rhythmic movements" such as the figure eight, and discrete point-to-point movement may be constructed from three different fundamental modules, one regulating the impedance of the limb over the time span of the movement and two others operating to generate movement, one aligned with the

Complementarity As Generative Principle: A Thought Pattern for Aesthetic Appreciations and Cognitive Appraisals in General

Science.gov (United States)

Bao, Yan; von Stosch, Alexandra; Park, Mona; Pöppel, Ernst

2017-01-01

In experimental aesthetics the relationship between the arts and cognitive neuroscience has gained particular interest in recent years. But has cognitive neuroscience indeed something to offer when studying the arts? Here we present a theoretical frame within which the concept of complementarity as a generative or creative principle is proposed; neurocognitive processes are characterized by the duality of complementary activities like bottom-up and top-down control, or logistical functions like temporal control and content functions like perceptions in the neural machinery. On that basis a thought pattern is suggested for aesthetic appreciations and cognitive appraisals in general. This thought pattern is deeply rooted in the history of philosophy and art theory since antiquity; and complementarity also characterizes neural operations as basis for cognitive processes. We then discuss some challenges one is confronted with in experimental aesthetics; in our opinion, one serious problem is the lack of a taxonomy of functions in psychology and neuroscience which is generally accepted. This deficit makes it next to impossible to develop acceptable models which are similar to what has to be modeled. Another problem is the severe language bias in this field of research as knowledge gained in many languages over the ages remains inaccessible to most scientists. Thus, an inspection of research results or theoretical concepts is necessarily too narrow. In spite of these limitations we provide a selective summary of some results and viewpoints with a focus on visual art and its appreciation. It is described how questions of art and aesthetic appreciations using behavioral methods and in particular brain-imaging techniques are analyzed and evaluated focusing on such issues like the representation of artwork or affective experiences. Finally, we emphasize complementarity as a generative principle on a practical level when artists and scientists work directly together which can

Complementarity As Generative Principle: A Thought Pattern for Aesthetic Appreciations and Cognitive Appraisals in General

Directory of Open Access Journals (Sweden)

Yan Bao

2017-05-01

Full Text Available In experimental aesthetics the relationship between the arts and cognitive neuroscience has gained particular interest in recent years. But has cognitive neuroscience indeed something to offer when studying the arts? Here we present a theoretical frame within which the concept of complementarity as a generative or creative principle is proposed; neurocognitive processes are characterized by the duality of complementary activities like bottom-up and top-down control, or logistical functions like temporal control and content functions like perceptions in the neural machinery. On that basis a thought pattern is suggested for aesthetic appreciations and cognitive appraisals in general. This thought pattern is deeply rooted in the history of philosophy and art theory since antiquity; and complementarity also characterizes neural operations as basis for cognitive processes. We then discuss some challenges one is confronted with in experimental aesthetics; in our opinion, one serious problem is the lack of a taxonomy of functions in psychology and neuroscience which is generally accepted. This deficit makes it next to impossible to develop acceptable models which are similar to what has to be modeled. Another problem is the severe language bias in this field of research as knowledge gained in many languages over the ages remains inaccessible to most scientists. Thus, an inspection of research results or theoretical concepts is necessarily too narrow. In spite of these limitations we provide a selective summary of some results and viewpoints with a focus on visual art and its appreciation. It is described how questions of art and aesthetic appreciations using behavioral methods and in particular brain-imaging techniques are analyzed and evaluated focusing on such issues like the representation of artwork or affective experiences. Finally, we emphasize complementarity as a generative principle on a practical level when artists and scientists work

Spatial temporal patterns for action-oriented perception in roving robots

CERN Document Server

Patanè, Luca

2014-01-01

This book presents the result of a joint effort from different European Institutions within the framework of the EU funded project called SPARK II, devoted to device an insect brain computational model, useful to be embedded into autonomous robotic agents.  Part I reports the biological background on Drosophila melanogaster with particular attention to the main centers which are used as building blocks for the implementation of the insect brain computational model.  Part II  reports the mathematical approach to model the Central Pattern Generator used for the gait generation in a six-legged robot. Also the Reaction-diffusion principles in non-linear lattices are exploited to develop a compact internal representation of a dynamically changing environment for behavioral planning. In Part III  a software/hardware framework, developed to integrate the insect brain computational model in a simulated/real robotic platform, is illustrated. The different robots used for the experiments are also described.  Moreo...

Patterns of Care in Proton Radiation Therapy for Pediatric Central Nervous System Malignancies

International Nuclear Information System (INIS)

Odei, Bismarck; Frandsen, Jonathan E.; Boothe, Dustin; Ermoian, Ralph P.; Poppe, Matthew M.

2017-01-01

Purpose: Proton beam therapy (PBT) potentially allows for improved sparing of normal tissues, hopefully leading to decreased late side effects in children. Using a national registry, we sought to perform a patterns-of-care analysis for children receiving PBT for primary malignancies of the central nervous system (CNS). Methods and Materials: Using the National Cancer Data Base, we identified pediatric patients with primary CNS malignancies that were diagnosed between 2004 and 2012. We used a standard t test for comparison of means and χ"2 testing to identify differences in demographic and clinical characteristics. Univariate and multivariate logistical regression was applied to identify predictors of PBT use. Results: We identified 4637 pediatric patients receiving radiation therapy from 2004 to 2012, including a subset of 267 patients treated with PBT. We found that PBT use increased with time from 200 miles from a radiation treatment facility (P<.05). Conclusions: We noted the proportion of children receiving PBT to be significantly increasing over time from <1% to 15% from 2004 to 2012. We also observed important disparities in receipt of PBT based on socioeconomic status. Children from higher-income households and with private insurance were more likely to use this expensive technology. As we continue to demonstrate the potential benefits of PBT in children, efforts are needed to expand the accessibility of PBT for children of all socioeconomic backgrounds and regions of the country.

Flip, flop and fly: modulated motor control and highly variable movement patterns of autotomized gecko tails.

Science.gov (United States)

Higham, Timothy E; Russell, Anthony P

2010-02-23

Many animals lose and regenerate appendages, and tail autotomy in lizards is an extremely well-studied example of this. Whereas the energetic, ecological and functional ramifications of tail loss for many lizards have been extensively documented, little is known about the behaviour and neuromuscular control of the autotomized tail. We used electromyography and high-speed video to quantify the motor control and movement patterns of autotomized tails of leopard geckos (Eublepharis macularius). In addition to rhythmic swinging, we show that they exhibit extremely complex movement patterns for up to 30 min following autotomy, including acrobatic flips up to 3 cm in height. Unlike the output of most central pattern generators (CPGs), muscular control of the tail is variable and can be arrhythmic. We suggest that the gecko tail is well suited for studies involving CPGs, given that this spinal preparation is naturally occurring, requires no surgery and exhibits complex modulation.

Children with central and peripheral neurologic disorders have distinguishable patterns of dysphagia on videofluoroscopic swallow study.

Science.gov (United States)

van den Engel-Hoek, Lenie; Erasmus, Corrie E; van Hulst, Karen C M; Arvedson, Joan C; de Groot, Imelda J M; de Swart, Bert J M

2014-05-01

To determine whether findings on videofluoroscopic swallow studies reveal different patterns of dysphagia between children with central and peripheral neurologic disorders, a retrospective study of 118 videofluoroscopic swallow studies was completed. There were 3 groups: cerebral palsy with only spastic features (n = 53), cerebral palsy with dyskinetic features (n = 34), and neuromuscular disorders (myotonic dystrophy I, n = 5; spinal muscular atrophy I-II, n = 8; Duchenne muscular dystrophy, n = 8; other neuromuscular disorder, n = 10). Interpretation of the videofluoroscopic swallow studies was not blinded. The video fluoroscopic swallow study findings were compared dichotomously between the groups. Children with cerebral palsy demonstrated dysphagia in 1 or all phases of swallowing. In neuromuscular disorder, muscle weakness results in pharyngeal residue after swallow. The underlying swallowing problem in neuromuscular disorder is muscle weakness whereas that in cerebral palsy is more complex, having to do with abnormal control of swallowing. This study serves as a first exploration on specific characteristics of swallowing in different neurologic conditions and will help clinicians anticipate what they might expect.

Recent developments for the pattern recognition in the central drift chamber of the Belle II detector

Energy Technology Data Exchange (ETDEWEB)

Trusov, Viktor; Feindt, Michael; Heck, Martin; Hauth, Thomas; Goldenzweig, Pablo [Karlsruhe Institute of Technology (Germany); Collaboration: Belle II-Collaboration

2016-07-01

The Belle II experiment is designed to perform more precise measurements (e.g. C P-violation measurements, New Physics phenomena, rare decays etc) than its predecessor, the Belle experiment. To achieve this goal, the luminosity of the experiment will be increased by a factor of 40 and as result multiple times more data will be collected. Due to this fact, faster reconstruction algorithms for the data processing need to be developed and at the same time accurate physical results should be retained. One important part in the data processing chain is the track reconstruction section. We present the development of one of the pattern recognition algorithms for the Belle II experiment based on conformal and Legendre transformations. In order to optimize the performance of the algorithm (CPU time and efficiency) we have introduced specialized processing steps. To show improvements in the results we introduce efficiency measurements of the tracking algorithms in the Central Drift Chamber (CDC) which were done using Monte-Carlo simulation of e{sup +} e{sup -} collisions followed by a full simulation of the Belle II detector.

Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data

Directory of Open Access Journals (Sweden)

Regad Leslie

2010-01-01

Full Text Available Abstract Background In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.. Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models. Results The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence. Conclusions Our algorithms prove to be effective and able to handle real data sets with

Generative electronic background music system

Energy Technology Data Exchange (ETDEWEB)

Mazurowski, Lukasz [Faculty of Computer Science, West Pomeranian University of Technology in Szczecin, Zolnierska Street 49, Szczecin, PL (Poland)

2015-03-10

In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions.

Generative electronic background music system

International Nuclear Information System (INIS)

Mazurowski, Lukasz

2015-01-01

In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions

Comparative mapping of GABA-immunoreactive neurons in the central nervous systems of nudibranch molluscs.

Science.gov (United States)

Gunaratne, Charuni A; Sakurai, Akira; Katz, Paul S

2014-03-01

The relative simplicity of certain invertebrate nervous systems, such as those of gastropod molluscs, allows behaviors to be dissected at the level of small neural circuits composed of individually identifiable neurons. Elucidating the neurotransmitter phenotype of neurons in neural circuits is important for understanding how those neural circuits function. In this study, we examined the distribution of γ-aminobutyric-acid;-immunoreactive (GABA-ir) neurons in four species of sea slugs (Mollusca, Gastropoda, Opisthobranchia, Nudibranchia): Tritonia diomedea, Melibe leonina, Dendronotus iris, and Hermissenda crassicornis. We found consistent patterns of GABA immunoreactivity in the pedal and cerebral-pleural ganglia across species. In particular, there were bilateral clusters in the lateral and medial regions of the dorsal surface of the cerebral ganglia as well as a cluster on the ventral surface of the pedal ganglia. There were also individual GABA-ir neurons that were recognizable across species. The invariant presence of these individual neurons and clusters suggests that they are homologous, although there were interspecies differences in the numbers of neurons in the clusters. The GABAergic system was largely restricted to the central nervous system, with the majority of axons confined to ganglionic connectives and commissures, suggesting a central, integrative role for GABA. GABA was a candidate inhibitory neurotransmitter for neurons in central pattern generator (CPG) circuits underlying swimming behaviors in these species, however none of the known swim CPG neurons were GABA-ir. Although the functions of these GABA-ir neurons are not known, it is clear that their presence has been strongly conserved across nudibranchs. Copyright © 2013 Wiley Periodicals, Inc.

Demonstration of electronic pattern switching and 10x pattern demagnification in a maskless micro-ion beam reduction lithography system

International Nuclear Information System (INIS)

Ngo, V.V.; Akker, B.; Leung, K.N.; Noh, I.; Scott, K.L.; Wilde, S.

2002-01-01

A proof-of-principle ion projection lithography (IPL) system called Maskless Micro-ion beam Reduction Lithography (MMRL) has been developed and tested at the Lawrence Berkeley National Laboratory (LBNL) for future integrated circuits (ICs) manufacturing and thin film media patterning [1]. This MMRL system is aimed at completely eliminating the first stage of the conventional IPL system [2] that contains the complicated beam optics design in front of the stencil mask and the mask itself. It consists of a multicusp RF plasma generator, a multi-beamlet pattern generator, and an all-electrostatic ion optical column. Results from ion beam exposures on PMMA and Shipley UVII-HS resists using 75 keV H+ are presented in this paper. Proof-of-principle electronic pattern switching together with 10x reduction ion optics (using a pattern generator made of nine 50-(micro)m switchable apertures) has been performed and is reported in this paper. In addition, the fabrication of a micro-fabricated pattern generator [3] on an SOI membrane is also presented

Are Dietary Patterns of Mothers during Pregnancy Related to Childrens Weight Status? Evidence from the Lifeways Cross-Generational Cohort Study

Directory of Open Access Journals (Sweden)

Celine M Murrin

2015-07-01

Full Text Available Children's diet patterns are likely to be influenced by their mothers' diet pattern. The primary objective of this study was to examine whether children's adiposity could be influenced by diet patterns of mothers during pregnancy. A secondary objective was to study the relative influence of fathers' and children's dietary patterns on childhood adiposity. The design was a prospective cross-generational cohort study initiated with 1,124 mothers recruited during pregnancy. Self-reported questionnaires included a food frequency instrument (FFQ to assess parental intakes during the perinatal period. Child body mass index (BMI was measured at 5 years and an age-appropriate FFQ was administered. Dietary patterns for each group were identified by principal components analysis. Pearson's correlation and logistic regression were used to test for associations. Dietary patterns were described for n = 1,042 mothers during pregnancy and n = 331 fathers during the perinatal period. Dietary patterns and BMI data were available for n = 443 children at age 5 years. The diet patterns identified for mothers correlated with the corresponding diet patterns for fathers. The children's “pasta & vegetable” pattern was positively correlated with “healthy patterns” in mothers (r = 0.195, p < 0.01 and fathers (r = 0.250, p < 0.01. The children's “junk” food pattern was correlated with the “processed” pattern in mothers (r = 0.245, p < 0.01 and fathers (r = 0.257, p < 0.01. In multivariate logistic regression analysis the upper tertiles of children's “cereal and juice” [Tertile 2 (T2: OR 0.44, 95% CI (0.22-0.90; T3: 0.41, (0.19-0.85] and the middle tertile of the “pasta and veg” patterns [T3: 0.37, (0.18-0.75] were negatively associated with overweight and obesity. The mothers' processed pattern during pregnancy was positively associated with offspring overweight and obesity [T2: 2.64, (1.28-5.45; T3: 2.03, (0.87-4.73]. No significant associations

Spatial-temporal evolution of self-organized loop-patterns on a water surface and a diffuse discharge in the gap

Science.gov (United States)

Li, Xuechen; Geng, Jinling; Jia, Pengying; Zhang, Panpan; Zhang, Qi; Li, Yaru

2017-11-01

Excited by an alternating current voltage, a patterned discharge and a diffuse discharge are generated in a needle to liquid configuration. Using an intensified charge-coupled device (ICCD), temporal evolution of the discharge between the two electrodes is investigated for the diffuse mode and the patterned mode, respectively. For the diffuse mode, the positive discharge is in a glow regime, and the negative discharge is in a Townsend discharge regime. For the patterned mode, the discharge always belongs to the Townsend discharge regime. Moreover, in the patterned mode, various patterns including the single loop, single loop with the surrounding corona, triple loops, and concentric loops with a central spot are observed on the water surface with the increasing positive peak-value of the applied voltage (Upp). Temporally resolved images of the loop-patterns are captured on the water surface. From the electrical measurements and the ICCD imaging, it is found that the loop pattern emerges after the discharge bridges the two electrodes. Then, it begins to evolve and finally degenerates with the decrease in the discharge current. The pattern does not disappear until the discharge quenches. Formation of the loop-patterns is attributed to the role of negative ions.

Genetic structure of Quechua-speakers of the Central Andes and geographic patterns of gene frequencies in South Amerindian populations.

Science.gov (United States)

Luiselli, D; Simoni, L; Tarazona-Santos, E; Pastor, S; Pettener, D

2000-09-01

A sample of 141 Quechua-speaking individuals of the population of Tayacaja, in the Peruvian Central Andes, was typed for the following 16 genetic systems: ABO, Rh, MNSs, P, Duffy, AcP1, EsD, GLOI, PGM1, AK, 6-PGD, Hp, Gc, Pi, C3, and Bf. The genetic structure of the population was analyzed in relation to the allele frequencies available for other South Amerindian populations, using a combination of multivariate and multivariable techniques. Spatial autocorrelation analysis was performed independently for 13 alleles to identify patterns of gene flow in South America as a whole and in more specific geographic regions. We found a longitudinal cline for the AcP1*a and EsD*1 alleles which we interpreted as the result of an ancient longitudinal expansion of a putative ancestral population of modern Amerindians. Monmonnier's algorithm, used to identify areas of sharp genetic discontinuity, suggested a clear east-west differentiation of native South American populations, which was confirmed by analysis of the distribution of genetic distances. We suggest that this pattern of genetic structures is the consequence of the independent peopling of western and eastern South America or to low levels of gene flow between these regions, related to different environmental and demographic histories. Copyright 2000 Wiley-Liss, Inc.

Migration patterns and movements of sandhill cranes wintering in central and southwestern Louisiana

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King, Sammy L.; Pierce, Aaron R.; Hersey, Kent R.; Winstead, Nicholas; Hartup, Barry K.

2010-01-01

In this study we trapped wintering sandhill cranes (Grus canadensis) in Louisiana and fitted them with satellite transmitters to determine their migration routes. Four of the 6 sandhill cranes with validated locations and a terminus point used the Central Flyway for spring migration; 2 of these 4 (the only 2 for which we have data) also used the Central Flyway for fall migration. Two of the 6 birds used the Mississippi Flyway for spring migration. The results of this study suggest that reintroduced whooping cranes (G. americana) that intermix and migrate with sandhill cranes that winter in Louisiana may enter the Central Flyway. In addition, the Mississippi Flyway is a viable option to use as a migration route for whooping cranes if they are reintroduced in Louisiana.

Dietary Pattern Is Associated with Obesity in Older People in China: Data from China Health and Nutrition Survey (CHNS

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Xiaoyue Xu

2015-09-01

Full Text Available Background: No studies have been conducted to explore the associations between dietary patterns and obesity among older Chinese people, by considering gender and urbanization level differences. Methods: We analyzed data from the 2009 China Health and Nutrition Survey (2745 individuals, aged ≥ 60 years. Dietary data were obtained using 24 hour-recall over three consecutive days. Height, Body Weight, and Waist Circumference were measured. Exploratory factor analysis was used to identify dietary patterns. Multinomial and Poisson regression models were used to examine the association between dietary patterns and Body Mass Index (BMI status/central obesity. Results: The prevalence of general and central obesity was 9.5% and 53.4%. Traditional dietary pattern (high intake of rice, pork and vegetables was inversely associated with general/central obesity; modern dietary pattern (high intake of fruit, fast food, and processed meat was positively associated with general/central obesity. The highest quartile of traditional dietary pattern had a lower risk of general/central obesity compared with the lowest quartile, while an inverse picture was found for the modern dietary pattern. These associations were consistent by gender and urbanization levels. Conclusions: Dietary patterns are associated with general/central obesity in older Chinese. This study reinforces the importance of a healthy diet in promoting healthy ageing in China.

Dietary Pattern Is Associated with Obesity in Older People in China: Data from China Health and Nutrition Survey (CHNS).

Science.gov (United States)

Xu, Xiaoyue; Hall, John; Byles, Julie; Shi, Zumin

2015-09-23

No studies have been conducted to explore the associations between dietary patterns and obesity among older Chinese people, by considering gender and urbanization level differences. We analyzed data from the 2009 China Health and Nutrition Survey (2745 individuals, aged ≥ 60 years). Dietary data were obtained using 24 hour-recall over three consecutive days. Height, Body Weight, and Waist Circumference were measured. Exploratory factor analysis was used to identify dietary patterns. Multinomial and Poisson regression models were used to examine the association between dietary patterns and Body Mass Index (BMI) status/central obesity. The prevalence of general and central obesity was 9.5% and 53.4%. Traditional dietary pattern (high intake of rice, pork and vegetables) was inversely associated with general/central obesity; modern dietary pattern (high intake of fruit, fast food, and processed meat) was positively associated with general/central obesity. The highest quartile of traditional dietary pattern had a lower risk of general/central obesity compared with the lowest quartile, while an inverse picture was found for the modern dietary pattern. These associations were consistent by gender and urbanization levels. Dietary patterns are associated with general/central obesity in older Chinese. This study reinforces the importance of a healthy diet in promoting healthy ageing in China.

Patterns of regional development in Serbia: A multivariate statistical analysis

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Čoček Ladislav

2010-01-01

Full Text Available The primary objective of this paper is to examine patterns of regional development in Serbia and to identify underlying geographical factors of these patterns. Principal component analysis is used to reveal the basic dimensions of regional differentiation. Its results are described in the context of findings from thematically similar research on Central European countries. An area's position in the national settlement system hierarchy has been identified as the strongest determinant of regional differentiation in Serbia. Other strong patterns seem to be connected with macro-geographical position. Success in economic development is most apparent in regions near the metropolitan area of Belgrade, and the general development level, along with a predisposition for agriculture, exhibits a strong north-south polarization. Specific attention is directed at demographic development, which is characterized by a west-east gradient. Central patterns of regional differentiation are similar to those uncovered in previous Central European research. Regional policy in Serbia should, therefore, try to learn from experience within this region to cope with processes and problems that are often quite similar. .

A two-step patterning process increases the robustness of periodic patterning in the fly eye.

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Gavish, Avishai; Barkai, Naama

2016-06-01

Complex periodic patterns can self-organize through dynamic interactions between diffusible activators and inhibitors. In the biological context, self-organized patterning is challenged by spatial heterogeneities ('noise') inherent to biological systems. How spatial variability impacts the periodic patterning mechanism and how it can be buffered to ensure precise patterning is not well understood. We examine the effect of spatial heterogeneity on the periodic patterning of the fruit fly eye, an organ composed of ∼800 miniature eye units (ommatidia) whose periodic arrangement along a hexagonal lattice self-organizes during early stages of fly development. The patterning follows a two-step process, with an initial formation of evenly spaced clusters of ∼10 cells followed by a subsequent refinement of each cluster into a single selected cell. Using a probabilistic approach, we calculate the rate of patterning errors resulting from spatial heterogeneities in cell size, position and biosynthetic capacity. Notably, error rates were largely independent of the desired cluster size but followed the distributions of signaling speeds. Pre-formation of large clusters therefore greatly increases the reproducibility of the overall periodic arrangement, suggesting that the two-stage patterning process functions to guard the pattern against errors caused by spatial heterogeneities. Our results emphasize the constraints imposed on self-organized patterning mechanisms by the need to buffer stochastic effects. Author summary Complex periodic patterns are common in nature and are observed in physical, chemical and biological systems. Understanding how these patterns are generated in a precise manner is a key challenge. Biological patterns are especially intriguing, as they are generated in a noisy environment; cell position and cell size, for example, are subject to stochastic variations, as are the strengths of the chemical signals mediating cell-to-cell communication. The need

Rewrite Systems, Pattern Matching, and Code Generation

Science.gov (United States)

1988-06-09

fmd a local set L’ which includes L and define the transformation on L’ instead of on L. 11 The straightforward way to define tree transformations...Proposition 2.19 Both B-ftt and T-ftt include: REL relabelings FTA (t ,t) such that t e RECOG HOM homomorphisms LHOM linear homomorphisms The capabilities...fsa for the set of the structures of the original pattern set. The LB-fsa IS used to fmd the structural subpatterns matching a: each node of the

Laboratory Instrumentation Design Research for Scalable Next Generation Epitaxy: Non-Equilibrium Wide Application Epitaxial Patterning by Intelligent Control (NEW-EPIC). Volume 1. 3D Composition/Doping Control via Micromiror Patterned Deep UV Photodesorption: Revolutionary in situ Characterization/Control

Science.gov (United States)

2009-02-19

34 (to be submitted to APL) " Positron Annihilation Spectroscopy of Annealed and As-grown Be-doped GaN" (to be submitted to APL - delayed by the...WIDE APPLICATION EPITAXIAL PATTERNING BY INTELLIGENT CONTROL (NEW-EPIC) 6. AUTHOR(S) DRS DOOLITTILE, FRAZIER, BURNHAM, PRITCHETT, BILLINGSLEY...NEXT GENERATION EPITAXY: NON-EQUILIBRIUM WIDE APPLICATION EPITAXIAL PATTERNING BY INTELLIGENT CONTROL (NEW-EPIC) VOLUME I 3D COMPOSITION/DOPING

Centralized mouse repositories.

Science.gov (United States)

Donahue, Leah Rae; Hrabe de Angelis, Martin; Hagn, Michael; Franklin, Craig; Lloyd, K C Kent; Magnuson, Terry; McKerlie, Colin; Nakagata, Naomi; Obata, Yuichi; Read, Stuart; Wurst, Wolfgang; Hörlein, Andreas; Davisson, Muriel T

2012-10-01

Because the mouse is used so widely for biomedical research and the number of mouse models being generated is increasing rapidly, centralized repositories are essential if the valuable mouse strains and models that have been developed are to be securely preserved and fully exploited. Ensuring the ongoing availability of these mouse strains preserves the investment made in creating and characterizing them and creates a global resource of enormous value. The establishment of centralized mouse repositories around the world for distributing and archiving these resources has provided critical access to and preservation of these strains. This article describes the common and specialized activities provided by major mouse repositories around the world.

Performance analysis of a Kalina cycle for a central receiver solar thermal power plant with direct steam generation

International Nuclear Information System (INIS)

Modi, Anish; Haglind, Fredrik

2014-01-01

Solar thermal power plants have attracted increasing interest in the past few years – with respect to both the design of the various plant components, and extending the operation hours by employing different types of storage systems. One approach to improve the overall plant efficiency is to use direct steam generation with water/steam as both the heat transfer fluid in the solar receivers and the cycle working fluid. This enables operating the plant with higher turbine inlet temperatures. Available literature suggests that it is feasible to use ammonia-water mixtures at high temperatures without corroding the equipment by using suitable additives with the mixture. The purpose of the study reported here was to investigate if there is any benefit of using a Kalina cycle for a direct steam generation, central receiver solar thermal power plant with high live steam temperature (450 °C) and pressure (over 100 bar). Thermodynamic performance of the Kalina cycle in terms of the plant exergy efficiency was evaluated and compared with a simple Rankine cycle. The rates of exergy destruction for the different components in the two cycles were also calculated and compared. The results suggest that the simple Rankine cycle exhibits better performance than the Kalina cycle when the heat input is only from the solar receiver. However, when using a two-tank molten-salt storage system as the primary source of heat input, the Kalina cycle showed an advantage over the simple Rankine cycle because of about 33 % reduction in the storage requirement. The solar receiver showed the highest rate of exergy destruction for both the cycles. The rates of exergy destruction in other components of the cycles were found to be highly dependent on the amount of recuperation, and the ammonia mass fraction and pressure at the turbine inlet. - Highlights: •Kalina cycle for a central receiver solar thermal power plant with direct steam generation. •Rankine cycle shows better plant exergy

Dengue virus in sub-tropical northern and central Viet Nam: population immunity and climate shape patterns of viral invasion and maintenance.

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Maia A Rabaa

Full Text Available Dengue virus transmission occurs in both epidemic and endemic cycles across tropical and sub-tropical regions of the world. Incidence is particularly high in much of Southeast Asia, where hyperendemic transmission plagues both urban and rural populations. However, endemicity has not been established in some areas with climates that may not support year-round viral transmission. An understanding of how dengue viruses (DENV enter these environments and whether the viruses persist in inapparent local transmission cycles is central to understanding how dengue emerges in areas at the margins of endemic transmission. Dengue is highly endemic in tropical southern Vietnam, while increasingly large seasonal epidemics have occurred in northern Viet Nam over the last decade. We have investigated the spread of DENV-1 throughout Vietnam to determine the routes by which the virus enters northern and central regions of the country. Phylogeographic analysis of 1,765 envelope (E gene sequences from Southeast Asia revealed frequent movement of DENV between neighboring human populations and strong local clustering of viral lineages. Long-distance migration of DENV between human population centers also occurred regularly and on short time-scales, indicating human-mediated viral invasion into northern Vietnam. Human populations in southern Vietnam were found to be the primary source of DENV circulating throughout the country, while central and northern Vietnam acted as sink populations, likely due to reduced connectedness to other populations in the case of the central regions and to the influence of temperature variability on DENV replication and vector survival and competence in the north. Finally, phylogeographic analyses suggested that viral movement follows a gravity model and indicates that population immunity and physical and economic connections between populations may play important roles in shaping patterns of DENV transmission.

Contrasting evolution patterns between glacier-fed and non-glacier-fed lakes in the central Tibetan Plateau and driving force analysis

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Song, C.; Sheng, Y.

2015-12-01

High-altitude lakes in the Tibetan Plateau (TP) showed strong spatio-temporal variability during past decades. The lake dynamics can be associated with several key factors including lake type, supply of glacial meltwater, local climate variations. It is important to differentiate these factors when analyzing the driving force of lakes dynamics. With a focus on lakes over the Tanggula Mountains of the central TP, this study investigates the temporal evolution patterns of lake area and water level of different types: glacier-fed closed lake, non-glacier-fed closed lake and upstream lake (draining into closed lakes). We collected all available Landsat archive data and quantified the inter-annual variability of lake extents. Results show accelerated expansions of both glacier-fed and non-glacier-fed lakes during 1970s-2013, and different temporal patterns of the two types of lakes: the non-glacier-fed lakes displayed a batch-wise growth pattern, with obvious growth in 2002, 2005 and 2011 and slight changes in other years, while glacier-fed lakes showed steady expanding tendency. The contrasting patterns are confirmed by the distinction of lake level change between the two groups derived from satellite altimetry during 2003-2009. The upstream lakes remained largely stable due to natural drainage regulation. The intermittent expansions for non-glacier-fed lakes were found to be related to excessive precipitation events and positive "precipitation-evaporation". In contrast, glacier-fed lake changes showed weak correlations with precipitation variations, which imply a joint contribution from glacial meltwater to water budgets. A simple estimation reveals that the increased water storage for all of examined lakes contributed from precipitation/evaporation (0.31±0.09 Gt/yr) slightly overweighed the glacial meltwater supply (0.26±0.08 Gt/yr).

Patterns of death in the first and second generation immigrants from selected Middle Eastern countries in California.

Science.gov (United States)

Nasseri, Kiumarss; Moulton, Lawrence H

2011-04-01

Migrant studies in the United States (US) have rarely covered the Middle Eastern population (ME), and have never distinguished the first and second generations born in the US. This study aims to describe the mortality patterns of ME immigrants by origin, acculturation, and generation. Death certificates issued from 1997 through 2004 were used to calculate, for Middle Eastern immigrants, the proportional odds ratios (POR) for major causes of death, with comparison to non-Hispanic Whites born in the US to US-born parents. First generation immigrants had higher odds for colorectal cancers, diabetes, and diseases of the heart, while their odds for chronic obstructive pulmonary disease (COPD) and suicide were lower. Men had higher odds for all cancers combined, cancers of the lymphatics, and pancreas. Women had lower odds for lung cancer, and dementia, and higher odds for breast cancer. The second generation men had higher odds for all cancers combined, and diseases of the heart, whereas women had lower odds for lung cancer and cerebrovascular accidents. Higher odds for colorectal cancers and lower odds for COPD were noted in both sexes. Some of the observed differences may be based on ethnic characteristics, including genetic makeup, early exposures, and culturally determined values. Time since immigration is associated with convergence of most odds to that of the native population.

A Resilience Pattern in Village level: The Case Babalan Village, Pati, Central Java Indonesia

Science.gov (United States)

Nurwahyudi, Ragil; Maryono

2018-02-01

Based on the Indonesia Disaster Prone Index 2013, Pati Regency is a high risk area of disaster and is ranked 11th level Central Java province while nationally ranked 156. Babalan Village located on the edge of Juwana River has disaster history from 2006-2014 shows flood disaster Giving the greatest probability and impact followed by rat pest, tornado, drought, fire. The public recognizes the signs of a continuous flooding of heavy rains accompanied by clouds all over the edge, the continuous rise of the Juwana River surface to overflow, ants, isoptera, and animals out of its nest, "Yuyu Bule", earthworms out, clear water for "Rowo floods ", Brownish water for the flash floods. Most residents have boats and can make rafts from makeshift materials (jerry cans, bamboo, banana stems). Make "Ranggon" at home for those who do not evacuate for a place to stay during the flood. Citizens elevate the kitchen (to evacuate people and goods / household furniture). Breeding Tyto Alba owl for rats pest control post-flood and controllers in the fields. Develop vegetable crops in the yard with viticulture pattern (upstairs) if flood can be moved and can eat vegetables during flood. Have food reserves for stock before outside help comes. Citizens initiate "Water Bath honesty" to meet the water needs during the dry season.

A Resilience Pattern in Village level: The Case Babalan Village, Pati, Central Java Indonesia

Directory of Open Access Journals (Sweden)

Nurwahyudi Ragil

2018-01-01

Full Text Available Based on the Indonesia Disaster Prone Index 2013, Pati Regency is a high risk area of disaster and is ranked 11th level Central Java province while nationally ranked 156. Babalan Village located on the edge of Juwana River has disaster history from 2006-2014 shows flood disaster Giving the greatest probability and impact followed by rat pest, tornado, drought, fire. The public recognizes the signs of a continuous flooding of heavy rains accompanied by clouds all over the edge, the continuous rise of the Juwana River surface to overflow, ants, isoptera, and animals out of its nest, “Yuyu Bule”, earthworms out, clear water for “Rowo floods ”, Brownish water for the flash floods. Most residents have boats and can make rafts from makeshift materials (jerry cans, bamboo, banana stems. Make “Ranggon” at home for those who do not evacuate for a place to stay during the flood. Citizens elevate the kitchen (to evacuate people and goods / household furniture. Breeding Tyto Alba owl for rats pest control post-flood and controllers in the fields. Develop vegetable crops in the yard with viticulture pattern (upstairs if flood can be moved and can eat vegetables during flood. Have food reserves for stock before outside help comes. Citizens initiate “Water Bath honesty” to meet the water needs during the dry season.

Assessment of electricity generation and energy cost of wind energy conversion systems in north-central Nigeria

International Nuclear Information System (INIS)

Adaramola, M.S.; Paul, S.S.; Oyedepo, S.O.

2011-01-01

Highlights: → The wind energy potential and economic analysis in selected six locations in north central part of Nigeria are investigated. → Economical evaluation of the wind energy in the selected sites was made by using the levelised cost method. → Locations that are suitable electricity generation and small scale applications are identified. - Abstract: In this study, the wind energy potential and economic analysis in selected six locations in north central part of Nigeria were investigated using wind speed data that span between 19 and 37 years measured at 10 m height. The performance of small to medium size commercial wind turbine models were examined and economic evaluation of the wind energy in the selected sites was made by using the levelised cost method. The results showed that the cost of energy production per kWh for the selected sites vary between cents 4.02 and cents 166.79. It was shown that Minna is most viable site while Bida is found to be least among the sites considered. Using three selected wind turbine models (in Minna) as case study, an increase in the escalation rate of operating and maintenance cost from 0% to 10%, lead to an increase in the unit energy cost by about 7%. It was further shown that by increasing the escalation rate of inflation from 0% to 5%, the cost of energy decreases by about 29% while the discount rate (return on investment) decreases from 11.54% to 6.23%.

Spatiotemporal Patterns of Ice Mass Variations and the Local Climatic Factors in the Riparian Zone of Central Valley, California

Science.gov (United States)

Inamdar, P.; Ambinakudige, S.

2016-12-01

Californian icefields are natural basins of fresh water. They provide irrigation water to the farms in the central valley. We analyzed the ice mass loss rates, air temperature and land surface temperature (LST) in Sacramento and San Joaquin basins in California. The digital elevation models from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) were used to calculate ice mass loss rate between the years 2002 and 2015. Additionally, Landsat TIR data were used to extract the land surface temperature. Data from local weather stations were analyzed to understand the spatiotemporal trends in air temperature. The results showed an overall mass recession of -0.8 ± 0.7 m w.e.a-1. We also noticed an about 60% loss in areal extent of the glaciers in the study basins between 2000 and 2015. Local climatic factors, along with the global climate patterns might have influenced the negative trends in the ice mass loss. Overall, there was an increase in the air temperature by 0.07± 0.02 °C in the central valley between 2000 and 2015. Furthermore, LST increased by 0.34 ± 0.4 °C and 0.55± 0.1 °C in the Sacramento and San Joaquin basins. Our preliminary results show the decrease in area and mass of ice mass in the basins, and changing agricultural practices in the valley.

The Southern Central Andes vertical axis tectonic rotations: relations with the deformation pattern Rotaciones tectónicas según ejes verticales en los Andes Centrales del Sur: relaciones con el patrón de deformación

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Claudia Prezzi

2012-05-01

Full Text Available Along the Central Andes a pattern of vertical axis tectonic rotations has been paleomagnetically identified. Such rotations are counterclockwise north of Arica Deflection (~19°S and clockwise to the south. Different hypothesis and models have been proposed to explain the Central Andean Rotation Pattern (CARP. However, the CARP is a subject of ongoing debate. Recently, the quantity, quality, and geographic distribution of paleomagnetic data have expanded greatly. Such expansion has been accompanied by an increase in the knowledge of the deformation periods in the Andes, allowing a more detailed analysis of the temporal and spatial distribution of the detected rotations. We compiled and analyzed the available Cenozoic paleomagnetic data for the region extending between 19° and 27.5°S. The results suggest the possible existence of different rotational domains with distinct characteristics. We propose that in the Southern Central Andes, a close correlation would exist between the style and the temporal and spatial pattern of deformation and the amount of recorded vertical axis rotations. However, in order to further investigate such relationship, new paleomagnetic studies are necessary, particularly in the Eastern Cordillera domain, in Paleogene rocks cropping out in the Altiplano-Puna and in Neogene rocks of the forearc.En los Andes Centrales se ha identificado un patrón de rotaciones tectónicas según ejes verticales a través de estudios paleomagnéticos. Dichas rotaciones son en sentido antihorario al norte del codo de Arica (~19°S y en sentido horario hacia el sur. Distintos autores han propuesto diferentes hipótesis y modelos para tratar de explicar el Patrón de Rotaciones de los Andes Centrales (PRAC. Sin embargo, el PRAC sigue siendo objeto de debate. Recientemente, la cantidad, calidad y la distribución geográfica de los datos paleomagnéticos ha aumentado de manera notable. Dicho incremento ha sido acompañado por un importante

Computer program for automatic generation of BWR control rod patterns

International Nuclear Information System (INIS)

Taner, M.S.; Levine, S.H.; Hsia, M.Y.

1990-01-01

A computer program named OCTOPUS has been developed to automatically determine a control rod pattern that approximates some desired target power distribution as closely as possible without violating any thermal safety or reactor criticality constraints. The program OCTOPUS performs a semi-optimization task based on the method of approximation programming (MAP) to develop control rod patterns. The SIMULATE-E code is used to determine the nucleonic characteristics of the reactor core state

Seasonal and diel patterns of total gaseous mercury concentration in the atmosphere of the Central Valley of Costa Rica

International Nuclear Information System (INIS)

Castillo, Aylin; Valdes, Juan; Sibaja, Jose; Vega, Ilena; Alfaro, Rosa; Morales, Jose; Esquivel, Germain; Barrantes, Elisa; Black, Paleah; Lean, David

2011-01-01

Research highlights: → Elevated seasonal and daily patterns of total gaseous mercury (TGM) were observed in the Central Valley of Costa Rica 27 km south-east of the Poas volcano. → With the onset of the wet season TGM in late April, values increased from typical values near 10 to 905 ng m -3 . → During the day, TGM values increased until midday along with temperature and radiation but relative humidity showed a reciprocal pattern. → We conclude that elemental mercury from the volcano may react with atmospheric oxidants especially during the dry season and the mercury would be deposited to the ground. → With the onset of heavy rains, mercury in the soil is reduced and re-volatilized resulting in the high levels in atmospheric air at the end of April. - Abstract: Monitoring of Hg in the atmosphere near volcanoes is limited with no previous data for Costa Rica. Seasonal and daily patterns of total gaseous mercury (TGM) were observed at the main sampling location at the Universidad Nacional, Heredia, Costa Rica. The area (lat. 10.000230 long. -84.109499) is located in the Central Valley of Costa Rica and is 27 km SE of the Poas volcano (lat. 10.199486 long. -84.231388). Measurements were made from May 2008 to May 2009 at this location with some additional values obtained at other sites near the Poas volcano including San Luis and Grecia as well as near, Turrialba and Irazu volcanoes. Total gaseous Hg was determined in samples collected at a height of 2 m using the Tekran 2537A (Tekran Inc.) gas-phase Hg vapor analyzer. Meteorological data (temperature, relative humidity, wind speed, wind direction, radiation and precipitation) were obtained from the airport weather station located at Alajuela. Monthly precipitation is typically 85 mm during the dry season (December to April) with winds from the west. The wet season begins in late April and continues to December with monthly rainfall of 328 mm and winds from the NE. The annual mean temperature is 20 deg. C

Seasonal and diel patterns of total gaseous mercury concentration in the atmosphere of the Central Valley of Costa Rica

Energy Technology Data Exchange (ETDEWEB)

Castillo, Aylin; Valdes, Juan; Sibaja, Jose; Vega, Ilena; Alfaro, Rosa; Morales, Jose; Esquivel, Germain; Barrantes, Elisa [Laboratory for Atmospheric Chemistry, LAQAT-UNA, Universidad Nacional, P.O. Box 86-3000, Heredia (Costa Rica); Black, Paleah [Department of Biology, University of Ottawa, P.O. Box 450 Station A, Ottawa, Ontario, K1N 6N5 (Canada); Lean, David, E-mail: drslean@gmail.com [P.O. Box 309, Apsley, Ontario, K0L 1A0 (Canada)

2011-02-15

Research highlights: {yields} Elevated seasonal and daily patterns of total gaseous mercury (TGM) were observed in the Central Valley of Costa Rica 27 km south-east of the Poas volcano. {yields} With the onset of the wet season TGM in late April, values increased from typical values near 10 to 905 ng m{sup -3}. {yields} During the day, TGM values increased until midday along with temperature and radiation but relative humidity showed a reciprocal pattern. {yields} We conclude that elemental mercury from the volcano may react with atmospheric oxidants especially during the dry season and the mercury would be deposited to the ground. {yields} With the onset of heavy rains, mercury in the soil is reduced and re-volatilized resulting in the high levels in atmospheric air at the end of April. - Abstract: Monitoring of Hg in the atmosphere near volcanoes is limited with no previous data for Costa Rica. Seasonal and daily patterns of total gaseous mercury (TGM) were observed at the main sampling location at the Universidad Nacional, Heredia, Costa Rica. The area (lat. 10.000230 long. -84.109499) is located in the Central Valley of Costa Rica and is 27 km SE of the Poas volcano (lat. 10.199486 long. -84.231388). Measurements were made from May 2008 to May 2009 at this location with some additional values obtained at other sites near the Poas volcano including San Luis and Grecia as well as near, Turrialba and Irazu volcanoes. Total gaseous Hg was determined in samples collected at a height of 2 m using the Tekran 2537A (Tekran Inc.) gas-phase Hg vapor analyzer. Meteorological data (temperature, relative humidity, wind speed, wind direction, radiation and precipitation) were obtained from the airport weather station located at Alajuela. Monthly precipitation is typically 85 mm during the dry season (December to April) with winds from the west. The wet season begins in late April and continues to December with monthly rainfall of 328 mm and winds from the NE. The annual mean

Developmental heterogeneity in DNA packaging patterns influences T-cell activation and transmigration.

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Soumya Gupta

Full Text Available Cellular differentiation programs are accompanied by large-scale changes in nuclear organization and gene expression. In this context, accompanying transitions in chromatin assembly that facilitates changes in gene expression and cell behavior in a developmental system are poorly understood. Here, we address this gap and map structural changes in chromatin organization during murine T-cell development, to describe an unusual heterogeneity in chromatin organization and associated functional correlates in T-cell lineage. Confocal imaging of DNA assembly in cells isolated from bone marrow, thymus and spleen reveal the emergence of heterogeneous patterns in DNA organization in mature T-cells following their exit from the thymus. The central DNA pattern dominated in immature precursor cells in the thymus whereas both central and peripheral DNA patterns were observed in naïve and memory cells in circulation. Naïve T-cells with central DNA patterns exhibited higher mechanical pliability in response to compressive loads in vitro and transmigration assays in vivo, and demonstrated accelerated expression of activation-induced marker CD69. T-cell activation was characterized by marked redistribution of DNA assembly to a central DNA pattern and increased nuclear size. Notably, heterogeneity in DNA patterns recovered in cells induced into quiescence in culture, suggesting an internal regulatory mechanism for chromatin reorganization. Taken together, our results uncover an important component of plasticity in nuclear organization, reflected in chromatin assembly, during T-cell development, differentiation and transmigration.

MR findings of central nerocytoma

International Nuclear Information System (INIS)

Lee, Chang Hoon; Kim, Dong Ik; Lee, Byung Hee; Kim, Myung Soon

1997-01-01

Central neurocytoma is a reae neuronal differentiated intraventricular tomor of young adults. The purpose of this study was to evaluate the characteristic MR appearance of central neurocytoma. We retrospectively reviewed MR images of 12 patients with central neurocytoma, confirmed by ultrastructural and immunohistochemical study. We analyzed patient age, and on all sequences, tumor location, extension into the third ventricle, involvement of brain parenchyma, cyst, hemorrhage, vascular signal void and signal intensity ; and egree of Gd-enhancement was examined on MR images, pattern of calcification on CT, and neovascularity, tumor staining on angiography. Age distribution was wide ranging from 26 to 64 years ; the most frequent age group was the fourth decade (five patients). All tumors except one (in the third ventricle) were located in the lateral ventricle and most were seen in the region of the foramen of Monro (10 cases). Tumors showed extension into the third ventricle and involvement of parenchyma in three cases. The internal architecture of the tumor was heterogenous and consisted of cysts (83%), hemorrhage (25%) and vascular signal void (25%). The solid portion of the tumor showed variable signal intensity on T1-weighted images and iso or high signal intensity on T2- and proton density-weighted images. On MR imaging, mild to moderate heterogenous Gd-enhancement was seen in ten cases (83%), and on CT, a spotted, amorphous, nodular pattern of calcifications was seen in seven cases (63%). On angiography, neovasevlarity and tumor staining was seen in three cases (100%). The typical location of the lateral and third ventricles and MR imaging characteristics including variable signal intensity and heterogenous internal architecture are helpful in the diagnosis of central neurocytoma in young adults

Generational changes in materialism and work centrality, 1976-2007: associations with temporal changes in societal insecurity and materialistic role modeling.

Science.gov (United States)

Twenge, Jean M; Kasser, Tim

2013-07-01

We examined whether culture-level indices of threat, instability, and materialistic modeling were linked to the materialistic values of American 12th graders between 1976 and 2007 (N = 355,296). Youth materialism (such as the importance of money and of owning expensive material items) increased over the generations, peaking in the late 1980s to early 1990s with Generation X and then staying at historically high levels for Millennials (GenMe). Societal instability and disconnection (e.g., unemployment, divorce) and social modeling (e.g., advertising spending) had both contemporaneous and lagged associations with higher levels of materialism, with advertising most influential during adolescence and instability during childhood. Societal-level living standards during childhood predicted materialism 10 years later. When materialistic values increased, work centrality steadily declined, suggesting a growing discrepancy between the desire for material rewards and the willingness to do the work usually required to earn them.

The PWR loading pattern optimization in X-IMAGE

International Nuclear Information System (INIS)

Stevens, J.G.; Smith, K.S.; Rempe, K.R.; Downar, T.J.

1993-01-01

The design of reactor core loading patterns is difficult due to the staggering number of patterns. The integer nature and nonlinear neutronic response of core design preclude simple prescriptions for generation of the feasible patterns, much less optimization among feasible candidates. Fortunately, recent developments in optimization, graphical user interfaces (GUIs), and the speed and low cost of engineering workstations combine to make loading pattern automation possible. The optimization module SIMAN has been added to X-IMAGE to automatically generate high-quality core loadings

Preliminary report on theNeurology workload ina central hospital in ...

African Journals Online (AJOL)

Introduction: Identification of the local pattern of neurological diseases is expected to help setting the priorities for good planning of management and public education. Objectives: To identify the pattern of neurological disorders in a second biggest central hospital in Sudan. Methodology: Review of the diagnosis of 170 ...

Natural quasy-periodic binary structure with focusing property in near field diffraction pattern.

Science.gov (United States)

Mihailescu, Mona

2010-06-07

A naturally-inspired phase-only diffractive optical element with a circular symmetry given by a quasi-periodic structure of the phyllotaxis type is presented in this paper. It is generated starting with the characteristic parametric equations which are optimal for the golden angle interval. For some ideal geometrical parameters, the diffracted intensity distribution in near-field has a central closed ring with almost zero intensity inside. Its radius and intensity values depend on the geometry or non-binary phase distribution superposed onto the phyllotaxis geometry. Along propagation axis, the transverse diffraction patterns from the binary-phase diffractive structure exhibit a self-focusing behavior and a rotational motion.

The role of mediation institutions in Sweden and Denmark after centralized bargaining

DEFF Research Database (Denmark)

Ibsen, Christian Lyhne

2016-01-01

not explain the internal stability of bargaining coordination once established. This analysis stresses the role of mediation institutions of both countries for solving collective action problems in pattern bargaining by pegging other settlements to the manufacturing labour cost norm. Mediation capabilities......This article compares coordinated collective bargaining in Sweden and Denmark after centralized bargaining. Existing theories — power resource and cross-class alliance theory — seem capable of explaining the transition from centralized bargaining to pattern bargaining system. However, they do...

Statistical properties of bidimensional patterns generated from delayed and extended maps

International Nuclear Information System (INIS)

Giacomelli, G.; Lepri, S.; Politi, A.

1995-01-01

The space-time chaotic patterns associated with a class of dynamical systems ranging from delayed to extended maps are investigated. All the systems are constructed in such a way that the corresponding two-dimensional (2D) representation is characterized by the same updating rule in the bulk. The main difference among them is the direction of the ''time'' axis in the plane. Despite the different causality relations among the various models, the resulting patterns are shown to be statistically equivalent. In particular, the Kolmogorov-Sinai entropy density assumes always the same value. Therefore, it can be considered as an absolute indicator, measuring the amount of disorder of a 2D pattern. The Kaplan-Yorke dimension density is instead rule dependent: this indicator alone cannot be used to quantify the degrees of freedom of a given pattern; one must further specify the direction of propagation in the plane

Regional Educational Performance Patterns in Europe

Directory of Open Access Journals (Sweden)

Péter Radó

2011-01-01

Full Text Available The paper aims to contribute to the assessment of the contextual relevance of various educational policies through an analysis of three aspects of the performance profiles of European countries: participation, the quality of learning outcomes and the equity of learning outcomes. Comparative analysis of international student achievement assessment surveys and statistical data reveals three European performance patterns: the compensative education systems of North and Northwest Europe, the selective education systems of Central Europe and the attritional education systems of Southeast Europe. On the basis of the identified performance patterns, the paper provides a brief outline of major trends within the Central and Southeast European regions, shares reflections on the alignment of policies that fit the distinct context of the two regions and offers a conceptual framework for further comparative research.

Two-phase flow pattern measurements with a wire mesh sensor in a direct steam generating solar thermal collector

Science.gov (United States)

Berger, Michael; Mokhtar, Marwan; Zahler, Christian; Willert, Daniel; Neuhäuser, Anton; Schleicher, Eckhard

2017-06-01

At Industrial Solar's test facility in Freiburg (Germany), two phase flow patterns have been measured by using a wire mesh sensor from Helmholtz Zentrum Dresden-Rossendorf (HZDR). Main purpose of the measurements was to compare observed two-phase flow patterns with expected flow patterns from models. The two-phase flow pattern is important for the design of direct steam generating solar collectors. Vibrations should be avoided in the peripheral piping, and local dry-outs or large circumferential temperature gradients should be prevented in the absorber tubes. Therefore, the choice of design for operation conditions like mass flow and steam quality are an important step in the engineering process of such a project. Results of a measurement with the wire mesh sensor are the flow pattern and the plug or slug frequency at the given operating conditions. Under the assumption of the collector power, which can be assumed from previous measurements at the same collector and adaption with sun position and incidence angle modifier, also the slip can be evaluated for a wire mesh sensor measurement. Measurements have been performed at different mass flows and pressure levels. Transient behavior has been tested for flashing, change of mass flow, and sudden changes of irradiation (cloud simulation). This paper describes the measurements and the method of evaluation. Results are shown as extruded profiles in top view and in side view. Measurement and model are compared. The tests have been performed at low steam quality, because of the limits of the test facility. Conclusions and implications for possible future measurements at larger collectors are also presented in this paper.

Distributed power generation using microturbines

CSIR Research Space (South Africa)

Szewczuk, S

2008-11-01

Full Text Available At present, the bulk of the world is electricity is generated in central power stations. This approach, one of `economy of size generates electricity in large power stations and delivers it to load centres via an extensive network of transmission...

Recurrence quantification analysis of extremes of maximum and minimum temperature patterns for different climate scenarios in the Mesochora catchment in Central-Western Greece

Science.gov (United States)

Panagoulia, Dionysia; Vlahogianni, Eleni I.

2018-06-01

A methodological framework based on nonlinear recurrence analysis is proposed to examine the historical data evolution of extremes of maximum and minimum daily mean areal temperature patterns over time under different climate scenarios. The methodology is based on both historical data and atmospheric General Circulation Model (GCM) produced climate scenarios for the periods 1961-2000 and 2061-2100 which correspond to 1 × CO2 and 2 × CO2 scenarios. Historical data were derived from the actual daily observations coupled with atmospheric circulation patterns (CPs). The dynamics of the temperature was reconstructed in the phase-space from the time series of temperatures. The statistically comparing different temperature patterns were based on some discriminating statistics obtained by the Recurrence Quantification Analysis (RQA). Moreover, the bootstrap method of Schinkel et al. (2009) was adopted to calculate the confidence bounds of RQA parameters based on a structural preserving resampling. The overall methodology was implemented to the mountainous Mesochora catchment in Central-Western Greece. The results reveal substantial similarities between the historical maximum and minimum daily mean areal temperature statistical patterns and their confidence bounds, as well as the maximum and minimum temperature patterns in evolution under the 2 × CO2 scenario. A significant variability and non-stationary behaviour characterizes all climate series analyzed. Fundamental differences are produced from the historical and maximum 1 × CO2 scenarios, the maximum 1 × CO2 and minimum 1 × CO2 scenarios, as well as the confidence bounds for the two CO2 scenarios. The 2 × CO2 scenario reflects the strongest shifts in intensity, duration and frequency in temperature patterns. Such transitions can help the scientists and policy makers to understand the effects of extreme temperature changes on water resources, economic development, and health of ecosystems and hence to proceed to

Coupled chaotic oscillators and their relation to a central pattern ...

Indian Academy of Sciences (India)

Abstract. Animal locomotion employs different periodic patterns known as animal gaits. In 1993, Collins and Stewart recognized that gaits possessed certain symmetries and characterized the gaits of quadrupeds and bipeds using permutation symmetry groups, which impose constraints on the locomotion center called the ...

Weather patterns and hydro-climatological precursors of extreme floods in Switzerland since 1868

International Nuclear Information System (INIS)

Stucki, Peter; Rickli, Ralph; Broennimann, Stefan; Martius, Olivia; Wanner, Heinz; Bern Univ.; Grebner, Dietmar; Luterbacher, Juerg

2012-01-01

The generation of 24 extreme floods in large catchments of the central Alps is analyzed from instrumental and documentary data, newly digitized observations of precipitation (DigiHom) and 20 th Century Reanalysis (20CR) data. Extreme floods are determined by the 95 th percentile of differences between an annual flood and a defined contemporary flood. For a selection of six events between 1868 and 1910, we describe preconditioning elements such as precipitation, temperature, and snow cover anomalies. Specific weather patterns are assessed through a subjective analysis of three-dimensional atmospheric circulation. A focus is placed on synoptic-scale features including mid-tropospheric ascent, low-level moisture transport, propagation of cyclones, and temperature anomalies. We propose a hydro-meteorological classification of all 24 investigated events according to flood-generating weather conditions. Key elements of the upper-level synoptic-scale flow are summarized by five types: (i) pivoting cut-off lows, (ii) elongated cut-off lows, (iii) elongated troughs, (iv) waves (with a kink), and (v) approximately zonal flow over the Alpine region. We found that the most extreme floods (as above, but ≥ 98 th percentile) in Switzerland since 1868 were caused by the interaction of severe hydro-climatologic conditions with a flood-inducing weather situation. The 20CR data provide plausible synoptic-scale meteorological patterns leading to heavy precipitation. The proposed catalogue of weather patterns and hydro-climatologic precursors can give direction when anticipating the possibility of severe floods in the Alpine region. (orig.)

Origin of dolomites in a downslope biostrome, Jefferson Formation (Frasnian), central Idaho: evidence from REE patterns, stable isotopes, and petrography

Energy Technology Data Exchange (ETDEWEB)

Dorobek, S.L.

1987-08-01

A completely dolomitized coral-stromatoporoid biostrome occurs at the top of the Dark Dolomite member of the Jefferson Formation (Frasnian) at Grandview Canyon, Lost River Range, central Idaho. The biostrome overlies a thick sequence of dolostones that were deposited in slope to deep ramp settings. The biostrome, therefore, formed in an open marine setting after shallowing of deep water environments. Zoned dolospar cement fills dissolution vugs and tectonic fractures. Stable isotopes for zoned dolospar are -13.1 to -6.5 per thousand delta/sup 18/O (average - 11.5) and -1.5 to -0.1 per thousand delta/sup 13/C (average -0.4). REE patterns for zoned dolospar have positive Ce anomalies, but total REE abundance is similar to REE abundance for replacive dolomites. Stratigraphic occurrence in an open marine setting, stable isotopes, and REE patterns suggest replacive dolomite phases formed during shallow burial diagenesis with significant involvement of nonevaporated sea water. More negative Ce anomalies near the top of the biostrome suggest a diagenetic overprint by oxidizing meteoric waters. Zoned dolospar probably formed from warmer, reducing burial fluids. Carbon for zoned dolospar probably was recycled from preexisting dolomite. These data may be useful for interpreting the origin of other anomalous platform dolostones.

Neuromolecular Imaging Shows Temporal Synchrony Patterns between Serotonin and Movement within Neuronal Motor Circuits in the Brain

Directory of Open Access Journals (Sweden)

Patricia A. Broderick

2013-06-01

Full Text Available The present discourse links the electrical and chemical properties of the brain with neurotransmitters and movement behaviors to further elucidate strategies to diagnose and treat brain disease. Neuromolecular imaging (NMI, based on electrochemical principles, is used to detect serotonin in nerve terminals (dorsal and ventral striata and somatodendrites (ventral tegmentum of reward/motor mesocorticolimbic and nigrostriatal brain circuits. Neuronal release of serotonin is detected at the same time and in the same animal, freely moving and unrestrained, while open-field behaviors are monitored via infrared photobeams. The purpose is to emphasize the unique ability of NMI and the BRODERICK PROBE® biosensors to empirically image a pattern of temporal synchrony, previously reported, for example, in Aplysia using central pattern generators (CPGs, serotonin and cerebral peptide-2. Temporal synchrony is reviewed within the context of the literature on central pattern generators, neurotransmitters and movement disorders. Specifically, temporal synchrony data are derived from studies on psychostimulant behavior with and without cocaine while at the same time and continuously, serotonin release in motor neurons within basal ganglia, is detected. The results show that temporal synchrony between the neurotransmitter, serotonin and natural movement occurs when the brain is NOT injured via, e.g., trauma, addictive drugs or psychiatric illness. In striking contrast, in the case of serotonin and cocaine-induced psychostimulant behavior, a different form of synchrony and also asynchrony can occur. Thus, the known dysfunctional movement behavior produced by cocaine may well be related to the loss of temporal synchrony, the loss of the ability to match serotonin in brain with motor activity. The empirical study of temporal synchrony patterns in humans and animals may be more relevant to the dynamics of motor circuits and movement behaviors than are studies of

Neuromolecular Imaging Shows Temporal Synchrony Patterns between Serotonin and Movement within Neuronal Motor Circuits in the Brain.

Science.gov (United States)

Broderick, Patricia A

2013-06-21

The present discourse links the electrical and chemical properties of the brain with neurotransmitters and movement behaviors to further elucidate strategies to diagnose and treat brain disease. Neuromolecular imaging (NMI), based on electrochemical principles, is used to detect serotonin in nerve terminals (dorsal and ventral striata) and somatodendrites (ventral tegmentum) of reward/motor mesocorticolimbic and nigrostriatal brain circuits. Neuronal release of serotonin is detected at the same time and in the same animal, freely moving and unrestrained, while open-field behaviors are monitored via infrared photobeams. The purpose is to emphasize the unique ability of NMI and the BRODERICK PROBE® biosensors to empirically image a pattern of temporal synchrony, previously reported, for example, in Aplysia using central pattern generators (CPGs), serotonin and cerebral peptide-2. Temporal synchrony is reviewed within the context of the literature on central pattern generators, neurotransmitters and movement disorders. Specifically, temporal synchrony data are derived from studies on psychostimulant behavior with and without cocaine while at the same time and continuously, serotonin release in motor neurons within basal ganglia, is detected. The results show that temporal synchrony between the neurotransmitter, serotonin and natural movement occurs when the brain is NOT injured via, e.g., trauma, addictive drugs or psychiatric illness. In striking contrast, in the case of serotonin and cocaine-induced psychostimulant behavior, a different form of synchrony and also asynchrony can occur. Thus, the known dysfunctional movement behavior produced by cocaine may well be related to the loss of temporal synchrony, the loss of the ability to match serotonin in brain with motor activity. The empirical study of temporal synchrony patterns in humans and animals may be more relevant to the dynamics of motor circuits and movement behaviors than are studies of static parameters

Patterns of muscle activity underlying object-specific grasp by the macaque monkey.

Science.gov (United States)

Brochier, T; Spinks, R L; Umilta, M A; Lemon, R N

2004-09-01

During object grasp, a coordinated activation of distal muscles is required to shape the hand in relation to the physical properties of the object. Despite the fundamental importance of the grasping action, little is known of the muscular activation patterns that allow objects of different sizes and shapes to be grasped. In a study of two adult macaque monkeys, we investigated whether we could distinguish between EMG activation patterns associated with grasp of 12 differently shaped objects, chosen to evoke a wide range of grasping postures. Each object was mounted on a horizontal shuttle held by a weak spring (load force 1-2 N). Objects were located in separate sectors of a "carousel," and inter-trial rotation of the carousel allowed sequential presentation of the objects in pseudorandom order. EMG activity from 10 to 12 digit, hand, and arm muscles was recorded using chronically implanted electrodes. We show that the grasp of different objects was characterized by complex but distinctive patterns of EMG activation. Cluster analysis shows that these object-related EMG patterns were specific and consistent enough to identify the object unequivocally from the EMG recordings alone. EMG-based object identification required a minimum of six EMGs from simultaneously recorded muscles. EMG patterns were consistent across recording sessions in a given monkey but showed some differences between animals. These results identify the specific patterns of activity required to achieve distinct hand postures for grasping, and they open the way to our understanding of how these patterns are generated by the central motor network.

Power generation and the environment

International Nuclear Information System (INIS)

Robert, L.E.J.; Liss, P.S.; Saunders, P.A.H.

1990-01-01

This book reviews environmental aspects of large-scale power generation. It includes historic background of present-generation patterns and a discussion of fossil fuel, nuclear energy, and renewable technologies

Scalable patterning using laser-induced shock waves

Science.gov (United States)

Ilhom, Saidjafarzoda; Kholikov, Khomidkhodza; Li, Peizhen; Ottman, Claire; Sanford, Dylan; Thomas, Zachary; San, Omer; Karaca, Haluk E.; Er, Ali O.

2018-04-01

An advanced direct imprinting method with low cost, quick, and minimal environmental impact to create a thermally controllable surface pattern using the laser pulses is reported. Patterned microindents were generated on Ni50Ti50 shape memory alloys and aluminum using an Nd: YAG laser operating at 1064 nm combined with a suitable transparent overlay, a sacrificial layer of graphite, and copper grid. Laser pulses at different energy densities, which generate pressure pulses up to a few GPa on the surface, were focused through the confinement medium, ablating the copper grid to create plasma and transferring the grid pattern onto the surface. Scanning electron microscope and optical microscope images show that various patterns were obtained on the surface with high fidelity. One-dimensional profile analysis indicates that the depth of the patterned sample initially increases with the laser energy and later levels off. Our simulations of laser irradiation process also confirm that high temperature and high pressure could be generated when the laser energy density of 2 J/cm2 is used.

On central ideals of finitely generated binary (-1,1)-algebras

International Nuclear Information System (INIS)

Pchelintsev, S V

2002-01-01

In 1975 the author proved that the centre of a free finitely generated (-1,1)-algebra contains a non-zero ideal of the whole algebra. Filippov proved that in a free alternative algebra of rank ≥4 there exists a trivial ideal contained in the associative centre. Il'tyakov established that the associative nucleus of a free alternative algebra of rank 3 coincides with the ideal of identities of the Cayley-Dickson algebra. In the present paper the above-mentioned theorem of the author is extended to free finitely generated binary (-1,1)-algebras. Theorem. The centre of a free finitely generated binary (-1,1)-algebra of rank ≥3 over a field of characteristic distinct from 2 and 3 contains a non-zero ideal of the whole algebra. As a by-product, we shall prove that the T-ideal generated by the function (z,x,(x,x,y)) in a free binary (-1,1)-algebra of finite rank is soluble. We deduce from this that the basis rank of the variety of binary (-1,1)-algebras is infinite

The central nervous system

International Nuclear Information System (INIS)

Holmes, R.A.

1984-01-01

The first section presents a comprehensive evaluation of radionuclide imaging of the central nervous system and provides a comparison of the detection accuracies of radionuclide imaging (RNI) and XCT in certain lesions, realizing that the XCT results may vary when radiocontrast or newer generation XCT scanners are used. Although conventional radionuclide imaging of the central nervous system has experienced no significant changes over the last 7 years except for mild refinements, a new section has been added on positron emission tomography (PET). Most positron radiopharmaceuticals passively cross the intact blood-brain barrier, and their localization has catalyzed renewed interest in our ability to metabolically study and obtain images of the central nervous system. The section on radionuclide cisternography has been rewritten to reflect present day practice and the wider application of XCT in describing conditions affecting the ventricular system

Pattern graph rewrite systems

Directory of Open Access Journals (Sweden)

Aleks Kissinger

2014-03-01

Full Text Available String diagrams are a powerful tool for reasoning about physical processes, logic circuits, tensor networks, and many other compositional structures. Dixon, Duncan and Kissinger introduced string graphs, which are a combinatoric representations of string diagrams, amenable to automated reasoning about diagrammatic theories via graph rewrite systems. In this extended abstract, we show how the power of such rewrite systems can be greatly extended by introducing pattern graphs, which provide a means of expressing infinite families of rewrite rules where certain marked subgraphs, called !-boxes ("bang boxes", on both sides of a rule can be copied any number of times or removed. After reviewing the string graph formalism, we show how string graphs can be extended to pattern graphs and how pattern graphs and pattern rewrite rules can be instantiated to concrete string graphs and rewrite rules. We then provide examples demonstrating the expressive power of pattern graphs and how they can be applied to study interacting algebraic structures that are central to categorical quantum mechanics.

Central obesity and the Mediterranean diet: A systematic review of intervention trials.

Science.gov (United States)

Bendall, C L; Mayr, H L; Opie, R S; Bes-Rastrollo, M; Itsiopoulos, C; Thomas, C J

2017-10-17

Central obesity is associated with chronic low-grade inflammation, and is a risk factor for cardiometabolic syndrome. The Mediterranean diet pattern has a convincing evidence-base for improving cardiometabolic health. This review investigated the impact of Mediterranean diet interventions on central obesity, specifically. A systematic literature search was conducted in the MEDLINE, CINAHL, EMBASE and Cochrane library databases. Search terms included: 'Mediterranean Diet', 'Mediterranean dietary pattern', 'central obesity' and 'visceral fat'. The search was limited to English language and humans ≥18 years. Eighteen articles met the eligibility criteria and reported at least one outcome measure of central obesity with Mediterranean diet intervention. Central obesity measures included waist circumference (16 studies), waist-hip ratio (5 studies) and visceral fat (2 studies). Thirteen (72%) of the studies, totaling 7186 subjects (5168 subjects assigned to a Mediterranean Diet), reported a significant reduction in central obesity with a Mediterranean-type diet. However, seven out of these 13 interventions employed energy restriction, and only three showed a statistically significant favorable effect of the Mediterranean diet relative to a control group. This systematic review highlights the potential for a Mediterranean diet intervention to reduce central obesity and in turn reduce obesity-related chronic disease risk and associated public health burden.

Patterns of Care in Proton Radiation Therapy for Pediatric Central Nervous System Malignancies

Energy Technology Data Exchange (ETDEWEB)

Odei, Bismarck [University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California (United States); Frandsen, Jonathan E.; Boothe, Dustin [Department of Radiation Oncology, University of Utah Huntsman Cancer Hospital, Salt Lake City, Utah (United States); Ermoian, Ralph P. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, Washington (United States); Poppe, Matthew M., E-mail: Matthew.poppe@hci.utah.edu [Department of Radiation Oncology, University of Utah Huntsman Cancer Hospital, Salt Lake City, Utah (United States)

2017-01-01

Purpose: Proton beam therapy (PBT) potentially allows for improved sparing of normal tissues, hopefully leading to decreased late side effects in children. Using a national registry, we sought to perform a patterns-of-care analysis for children receiving PBT for primary malignancies of the central nervous system (CNS). Methods and Materials: Using the National Cancer Data Base, we identified pediatric patients with primary CNS malignancies that were diagnosed between 2004 and 2012. We used a standard t test for comparison of means and χ{sup 2} testing to identify differences in demographic and clinical characteristics. Univariate and multivariate logistical regression was applied to identify predictors of PBT use. Results: We identified 4637 pediatric patients receiving radiation therapy from 2004 to 2012, including a subset of 267 patients treated with PBT. We found that PBT use increased with time from <1% in 2004 to 15% in 2012. In multivariate logistical regression, we found the following to be predictors of receipt of PBT: private insurance, the highest income bracket, younger age, living in a metropolitan area, and residing >200 miles from a radiation treatment facility (P<.05). Conclusions: We noted the proportion of children receiving PBT to be significantly increasing over time from <1% to 15% from 2004 to 2012. We also observed important disparities in receipt of PBT based on socioeconomic status. Children from higher-income households and with private insurance were more likely to use this expensive technology. As we continue to demonstrate the potential benefits of PBT in children, efforts are needed to expand the accessibility of PBT for children of all socioeconomic backgrounds and regions of the country.

Analysis of chlorophyll fluorescence reveals stage specific patterns of chloroplast-containing cells during Arabidopsis embryogenesis

Directory of Open Access Journals (Sweden)

RICARDO I TEJOS

2010-01-01

Full Text Available The basic body plan of a plant is established early in embryogenesis when cells differentiate, giving rise to the apical and basal regions of the embryo. Using chlorophyll fluorescence as a marker for chloroplasts, we have detected specific patterns of chloroplast-containing cells at specific stages of embryogenesis. Non-randomly distributed chloroplast-containing cells are seen as early as the globular stage of embryogenesis in Arabidopsis. In the heart stage of embryogenesis, chloroplast containing cells are detected in epidermal cells as well as a central region of the heart stage embryo, forming a triangular septum of chloroplast-containing cells that divides the embryo into three equal sectors. Torpedo stage embryos have chloroplast-containing epidermal cells and a central band of chloroplast-containing cells in the cortex layer, just below the shoot apical meristem. In the walking-stick stage of embryogenesis, chloroplasts are present in the epidermal, cortex and endodermal cells. The chloroplasts appear reduced or absent from the provascular and columella cells of walking-stick stage embryos. These results suggest that there is a tight regulation of plastid differentiation during embryogenesis that generates specific patterns of chloroplast-containing cells in specific cell layers at specific stages of embryogenesis.

Centrally Banked Cryptocurrencies

OpenAIRE

Danezis, George; Meiklejohn, Sarah

2015-01-01

Current cryptocurrencies, starting with Bitcoin, build a decentralized blockchain-based transaction ledger, maintained through proofs-of-work that also generate a monetary supply. Such decentralization has benefits, such as independence from national political control, but also significant limitations in terms of scalability and computational cost. We introduce RSCoin, a cryptocurrency framework in which central banks maintain complete control over the monetary supply, but rely on a distribut...

Centrally Banked Cryptocurrencies

OpenAIRE

Danezis, G.; Meiklejohn, S.

2016-01-01

Current cryptocurrencies, starting with Bitcoin, build a decentralized blockchain-based transaction ledger, maintained through proofs-of-work that also serve to generate a monetary supply. Such decentralization has benefits, such as independence from national political control, but also significant limitations in terms of computational costs and scalability. We introduce RSCoin, a cryptocurrency framework in which central banks maintain complete control over the monetary supply, but rely on...

Liquid metal steam generator

International Nuclear Information System (INIS)

Wolowodiuk, W.

1975-01-01

A liquid metal heated steam generator is described which in the event of a tube failure quickly exhausts out of the steam generator the products of the reaction between the water and the liquid metal. The steam is generated in a plurality of bayonet tubes which are heated by liquid metal flowing over them between an inner cylinder and an outer cylinder. The inner cylinder extends above the level of liquid metal but below the main tube sheet. A central pipe extends down into the inner cylinder with a centrifugal separator between it and the inner cylinder at its lower end and an involute deflector plate above the separator so that the products of a reaction between the liquid metal and the water will be deflected downwardly by the deflector plate and through the separator so that the liquid metal will flow outwardly and away from the central pipe through which the steam and gaseous reaction products are exhausted. (U.S.)

The event generator SIMON

International Nuclear Information System (INIS)

Durand, D.; Lopez, O.; Nguyen, A.D.

1997-01-01

The utilization and development of SIMON generator work was conducted at LPC.This generator was conceived for simple and versatile simulations of different processes occurring in the nuclear collisions at Fermi Energies. At present it is utilized in a large number of French foreign laboratories. Particularly, certain analyses of INDRA data have been done by use of this generator: estimation of collective energy in the Xe + Sn and Gd + U central collisions; shape and space-time correlation analysis in fragment-fragment and particle-fragment output of the same system; calorimetric study of the Xe + Sn and Ar + Ni system; study of the vaporization for the Ar + Ni system. Recently a number of items were improved or modified, among which: the initial configuration was allowed to be non-spherical what permits the analysis of the semi-central collisions; a so-called pre-fragmentation emission may be included to estimate different time constants implied in the fragmentation process

Power generator in BWR type reactors

International Nuclear Information System (INIS)

Yoshida, Kenji.

1984-01-01

Purpose: To enable to perform stable and dynamic conditioning operation for nuclear fuels in BWR type reactors. Constitution: The conditioning operation for the nuclear fuels is performed by varying the reactor core thermal power in a predetermined pattern by changing the predetermined power changing pattern of generator power, the rising rate of the reactor core thermal power and the upper limit for the rising power of the reactor core thermal power are calculated and the power pattern for the generator is corrected by a power conditioning device such that the upper limit for the thermal power rising rate and the upper limit for the thermal power rising rate are at the predetermined levels. Thus, when the relation between the reactor core thermal power and the generator electrical power is fluctuated, the fluctuation is detected based on the variation in the thermal power rising rate and the limit value for the thermal power rising rate, and the correction is made to the generator power changing pattern so that these values take the predetermined values to thereby perform the stable conditioning operation for the nuclear fuels. (Moriyama, K.)

PatterNet: a system to learn compact physical design pattern representations for pattern-based analytics

Science.gov (United States)

Lutich, Andrey

2017-07-01

This research considers the problem of generating compact vector representations of physical design patterns for analytics purposes in semiconductor patterning domain. PatterNet uses a deep artificial neural network to learn mapping of physical design patterns to a compact Euclidean hyperspace. Distances among mapped patterns in this space correspond to dissimilarities among patterns defined at the time of the network training. Once the mapping network has been trained, PatterNet embeddings can be used as feature vectors with standard machine learning algorithms, and pattern search, comparison, and clustering become trivial problems. PatterNet is inspired by the concepts developed within the framework of generative adversarial networks as well as the FaceNet. Our method facilitates a deep neural network (DNN) to learn directly the compact representation by supplying it with pairs of design patterns and dissimilarity among these patterns defined by a user. In the simplest case, the dissimilarity is represented by an area of the XOR of two patterns. Important to realize that our PatterNet approach is very different to the methods developed for deep learning on image data. In contrast to "conventional" pictures, the patterns in the CAD world are the lists of polygon vertex coordinates. The method solely relies on the promise of deep learning to discover internal structure of the incoming data and learn its hierarchical representations. Artificial intelligence arising from the combination of PatterNet and clustering analysis very precisely follows intuition of patterning/optical proximity correction experts paving the way toward human-like and human-friendly engineering tools.

Solar Energy within the Central Valley, CA: Current Practices and Potential

Science.gov (United States)

Hoffacker, M. K.; Hernandez, R. R.; Allen, M. F.

2015-12-01

Utility-scale solar energy (USSE, ≥ 1 megawatt [MW]) systems are rapidly being deployed in the Central Valley of California, generating clean electricity and new job opportunities. Utility-scale solar energy systems require substantial quantities of land or space, often prompting an evaluation of environmental impacts and trade-offs when selecting their placement. Utilizing salt-contaminated agricultural land (as the sodium absorption and electrical conductivity values are unsuitably high), unsuitable for food production, and lands within the built environment (developed), can serve as a co-benefit opportunity when reclamation of these lands for USSE development is prioritized. In this study, we quantify the theoretical and generation-based solar energy potential for the Central Valley according to land-cover type, crop type, and for salt-contaminated lands. Further, we utilize the Carnegie Energy and Environmental Compatibility (CEEC) model to identify and prioritize solar energy, integrating environmental resource opportunities and constraints most relevant to the Central Valley. We use the CEEC model to generate a value-based environmental compatibility output for the Central Valley. The Central Valley extends across nearly 60,000 km2 of California with the potential of generating 21,800 - 30,300 TWh y-1 and 41,600 TWh y-1 of solar energy for photovoltaic (PV) and concentrating solar power (CSP), respectively. Pasture, hay, and cultivated crops comprise over half of the Central Valley, much of which is considered prime agriculture or of statewide or local importance for farming (28,200 km2). Together, approximately one-third of this region is salt-contaminated (16%) or developed (11%). This confers a generation-based potential of 5713 - 7891 TWh y-1 and 2770 TWh y-1 for PV and CSP, respectively. As energy, food, and land are inextricably linked, our study shows how land favorable for renewable energy systems can be used more effectively in places where land is

Legislation on renewable energy sources in Central America

International Nuclear Information System (INIS)

Rebollo, Jose

2000-01-01

This paper presents the development of renewable energy in Central America and the cooperation given by the European Comission in the promotion of renewable energy sources. Also discuss the current situation in energy demand in Central America and possible solutions linked to legislation that promotes the inversion of the private sector. The legal framework in each country of Central America is presented and its impact in the increasing of generation of energy through tax reductions, trading and prices

Are there co-occurrence patterns that structure snake communities in Central Brazil?

Science.gov (United States)

França, F G R; Araújo, A F B

2007-02-01

The main factors that structure Neotropical animal communities have been the subject of discussion in ecology communities. We used a set of null models to investigate the existence of structure in snake communities from the Cerrado in Central Brazil in relation to the co-occurrence of species and guilds concerning specific resources. We used fragments (conservation units) inside the Distrito Federal and neighbor municipalities. In spite of recent human colonization in the region from the end of the 1950s, intense habitat modification and fragmentation has taken place. Sixty three snake species are present in the Distrito Federal. Co-occurrence analysis of species and guilds associated to snake diets and habitats suggested a lack of organization. The homogeneity of habitats in Central Brazil and the minor importance of ecological effects can lead to random arrangement.

Source region of volcanism and seismicity pattern beneath Central American volcanoes

Czech Academy of Sciences Publication Activity Database

Špičák, Aleš; Hanuš, Václav; Vaněk, Jiří

2005-01-01

Roč. 236, 1/2 (2005), s. 149-172 ISSN 0077-7749 R&D Projects: GA ČR GA205/03/1203; GA AV ČR IAA3012303 Institutional research plan: CEZ:AV0Z30120515 Keywords : Central America * subduction * convergent plate margins Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.721, year: 2005

Crossover patterning by the beam-film model: analysis and implications.

Directory of Open Access Journals (Sweden)

Liangran Zhang

2014-01-01

Full Text Available Crossing-over is a central feature of meiosis. Meiotic crossover (CO sites are spatially patterned along chromosomes. CO-designation at one position disfavors subsequent CO-designation(s nearby, as described by the classical phenomenon of CO interference. If multiple designations occur, COs tend to be evenly spaced. We have previously proposed a mechanical model by which CO patterning could occur. The central feature of a mechanical mechanism is that communication along the chromosomes, as required for CO interference, can occur by redistribution of mechanical stress. Here we further explore the nature of the beam-film model, its ability to quantitatively explain CO patterns in detail in several organisms, and its implications for three important patterning-related phenomena: CO homeostasis, the fact that the level of zero-CO bivalents can be low (the "obligatory CO", and the occurrence of non-interfering COs. Relationships to other models are discussed.

Review and future perspective of central receiver design and performance

Science.gov (United States)

Zhu, Guangdong; Libby, Cara

2017-06-01

Concentrating solar power (CSP) technology provides a commercial solar option to the utility-scale electricity market. CSP is unique in its ability to include low-cost thermal storage; thus, it can generate electricity when the sun is not available and dispatch electricity to meet varying load requirements. Within the suite of CSP technologies, the central receiver design represents the state-of-the-art technology, promising low cost, high performance, and dispatchable energy production. Current total capacity of central receiver plants worldwide is about 1.0 gigawatt (electric) with operating plants in Spain and the United States, as well as projects under construction in Asia, the Middle East, and North Africa. Central receiver technology has been under development since the 1950s, and a variety of central receiver designs have been explored. A distinguishing feature is the heat transfer medium. Central receiver designs exist that use dense fluids, gases, and solid particles in this role. Water/steam and molten salt receivers have been adopted in current commercial plants and are often coupled with a steam-Rankine power cycle with an operating temperature of less than 600°C. Many new central receiver concepts, such as the volumetric air, supercritical carbon dioxide (sCO2), solid particle, and liquid-metal receiver designs, are under active research and development (R&D). New designs target operating temperatures generally higher than 700°C-800°C—and even above 1000°C—so that higher-performance power cycles such as the sCO2-Brayton cycle or air-Brayton/steam-Rankine combined cycle can be used to promote greater overall system efficiency. Central receiver thermal storage provides dispatchability unavailable from variable-output renewables such as solar photovoltaic and wind power. Case study analysis of the California grid shows that there is a limit on the amount of non-dispatchable renewable generation that the grid can accommodate, beyond which

Review and Future Perspective of Central Receiver Design and Performance

Energy Technology Data Exchange (ETDEWEB)

Zhu, Guangdong; Libby, Cara

2017-06-27

Concentrating solar power (CSP) technology provides a commercial solar option to the utility-scale electricity market. CSP is unique in its ability to include low-cost thermal storage; thus, it can generate electricity when the sun is not available and dispatch electricity to meet varying load requirements. Within the suite of CSP technologies, the central receiver design represents the state-of-the-art technology, promising low cost, high performance, and dispatchable energy production. Current total capacity of central receiver plants worldwide is about 1.0 gigawatt (electric) with operating plants in Spain and the United States, as well as projects under construction in Asia, the Middle East, and North Africa. Central receiver technology has been under development since the 1950s, and a variety of central receiver designs have been explored. A distinguishing feature is the heat transfer medium. Central receiver designs exist that use dense fluids, gases, and solid particles in this role. Water/steam and molten salt receivers have been adopted in current commercial plants and are often coupled with a steam-Rankine power cycle with an operating temperature of less than 600 degrees C. Many new central receiver concepts, such as the volumetric air, supercritical carbon dioxide (sCO2), solid particle, and liquid-metal receiver designs, are under active research and development (R&D). New designs target operating temperatures generally higher than 700 degrees C-800 degrees C -- and even above 1000 degrees C -- so that higher-performance power cycles such as the sCO2-Brayton cycle or air-Brayton/steam-Rankine combined cycle can be used to promote greater overall system efficiency. Central receiver thermal storage provides dispatchability unavailable from variable-output renewables such as solar photovoltaic and wind power. Case study analysis of the California grid shows that there is a limit on the amount of non-dispatchable renewable generation that the grid can

Comparative historical biogeography of three groups of Nearctic freshwater fishes across central Mexico.

Science.gov (United States)

Pérez-Rodríguez, R; Domínguez-Domínguez, O; Doadrio, I; Cuevas-García, E; Pérez-Ponce de León, G

2015-03-01

Biogeographic patterns of the three main Nearctic groups of continental fishes inhabiting river drainages in central Mexico (livebearing goodeids, southern Mexican notropins and species of Algansea, the last two representing independent lineages of cyprinids) were obtained and compared by following two approaches: an estimate of divergence times and using a well-defined biogeographic method. Three concordant biogeographic events were identified among the three groups, showing some evidence of a partially congruent evolutionary history. The analysed groups show at least three independent colonization events into central Mexico: two western routes, followed by the Goodeinae and members of Algansea, and an early Plateau route followed by southern notropins. The most recent common ancestor (MRCA) of each of the three freshwater fish groups diversified in central Mexico in the Late Miocene. The lack of a strong congruence in their biogeographic patterns, and the differences in species richness among the three clades might be evidence for distinct patterns of diversification. © 2015 The Fisheries Society of the British Isles.

Diagnostic Hypothesis Generation and Human Judgment

Science.gov (United States)

Thomas, Rick P.; Dougherty, Michael R.; Sprenger, Amber M.; Harbison, J. Isaiah

2008-01-01

Diagnostic hypothesis-generation processes are ubiquitous in human reasoning. For example, clinicians generate disease hypotheses to explain symptoms and help guide treatment, auditors generate hypotheses for identifying sources of accounting errors, and laypeople generate hypotheses to explain patterns of information (i.e., data) in the…

Bringing up the rear: new premotor interneurons add regional complexity to a segmentally distributed motor pattern

Science.gov (United States)

Norris, Brian J.; Doloc-Mihu, Anca; Calabrese, Ronald L.

2011-01-01

Central pattern generators (CPGs) pace and pattern many rhythmic activities. We have uncovered a new module in the heartbeat CPG of leeches that creates a regional difference in this segmentally distributed motor pattern. The core CPG consists of seven identified pairs and one unidentified pair of heart interneurons of which 5 pairs are premotor and inhibit 16 pairs of heart motor neurons. The heartbeat CPG produces a side-to-side asymmetric pattern of activity of the premotor heart interneurons corresponding to an asymmetric fictive motor pattern and an asymmetric constriction pattern of the hearts with regular switches between the two sides. The premotor pattern progresses from rear to front on one side and nearly synchronously on the other; the motor pattern shows corresponding intersegmental coordination, but only from segment 15 forward. In the rearmost segments the fictive motor pattern and the constriction pattern progress from front to rear on both sides and converge in phase. Modeling studies suggested that the known inhibitory inputs to the rearmost heart motor neurons were insufficient to account for this activity. We therefore reexamined the constriction pattern of intact leeches. We also identified electrophysiologically two additional pairs of heart interneurons in the rear. These new heart interneurons make inhibitory connections with the rear heart motor neurons, are coordinated with the core heartbeat CPG, and are dye-coupled to their contralateral homologs. Their strong inhibitory connections with the rearmost heart motor neurons and the small side-to-side phase difference of their bursting contribute to the different motor and beating pattern observed in the animal's rear. PMID:21775711

Distributed generation hits market

International Nuclear Information System (INIS)

Anon.

1997-01-01

The pace at which vendors are developing and marketing gas turbines and reciprocating engines for small-scale applications may signal the widespread growth of distributed generation. Loosely defined to refer to applications in which power generation equipment is located close to end users who have near-term power capacity needs, distributed generation encompasses a broad range of technologies and load requirements. Disagreement is inevitable, but many industry observers associate distributed generation with applications anywhere from 25 kW to 25 MW. Ten years ago, distributed generation users only represented about 2% of the world market. Today, that figure has increased to about 4 or 5%, and probably could settle in the 20% range within a 3-to-5-year period, according to Michael Jones, San Diego, Calif.-based Solar Turbines Inc. power generation marketing manager. The US Energy Information Administration predicts about 175 GW of generation capacity will be added domestically by 2010. If 20% comes from smaller plants, distributed generation could account for about 35 GW. Even with more competition, it's highly unlikely distributed generation will totally replace current market structures and central stations. Distributed generation may be best suited for making market inroads when and where central systems need upgrading, and should prove its worth when the system can't handle peak demands. Typical applications include small reciprocating engine generators at remote customer sites or larger gas turbines to boost the grid. Additional market opportunities include standby capacity, peak shaving, power quality, cogeneration and capacity rental for immediate demand requirements. Integration of distributed generation systems--using gas-fueled engines, gas-fired combustion engines and fuel cells--can upgrade power quality for customers and reduce operating costs for electric utilities

REGULAR PATTERN MINING (WITH JITTER ON WEIGHTED-DIRECTED DYNAMIC GRAPHS

Directory of Open Access Journals (Sweden)

A. GUPTA

2017-02-01

Full Text Available Real world graphs are mostly dynamic in nature, exhibiting time-varying behaviour in structure of the graph, weight on the edges and direction of the edges. Mining regular patterns in the occurrence of edge parameters gives an insight into the consumer trends over time in ecommerce co-purchasing networks. But such patterns need not necessarily be precise as in the case when some product goes out of stock or a group of customers becomes unavailable for a short period of time. Ignoring them may lead to loss of useful information and thus taking jitter into account becomes vital. To the best of our knowledge, no work has been yet reported to extract regular patterns considering a jitter of length greater than unity. In this article, we propose a novel method to find quasi regular patterns on weight and direction sequences of such graphs. The method involves analysing the dynamic network considering the inconsistencies in the occurrence of edges. It utilizes the relation between the occurrence sequence and the corresponding weight and direction sequences to speed up this process. Further, these patterns are used to determine the most central nodes (such as the most profit yielding products. To accomplish this we introduce the concept of dynamic closeness centrality and dynamic betweenness centrality. Experiments on Enron e-mail dataset and a synthetic dynamic network show that the presented approach is efficient, so it can be used to find patterns in large scale networks consisting of many timestamps.

Environmental context explains Lévy and Brownian movement patterns of marine predators.

Science.gov (United States)

Humphries, Nicolas E; Queiroz, Nuno; Dyer, Jennifer R M; Pade, Nicolas G; Musyl, Michael K; Schaefer, Kurt M; Fuller, Daniel W; Brunnschweiler, Juerg M; Doyle, Thomas K; Houghton, Jonathan D R; Hays, Graeme C; Jones, Catherine S; Noble, Leslie R; Wearmouth, Victoria J; Southall, Emily J; Sims, David W

2010-06-24

An optimal search theory, the so-called Lévy-flight foraging hypothesis, predicts that predators should adopt search strategies known as Lévy flights where prey is sparse and distributed unpredictably, but that Brownian movement is sufficiently efficient for locating abundant prey. Empirical studies have generated controversy because the accuracy of statistical methods that have been used to identify Lévy behaviour has recently been questioned. Consequently, whether foragers exhibit Lévy flights in the wild remains unclear. Crucially, moreover, it has not been tested whether observed movement patterns across natural landscapes having different expected resource distributions conform to the theory's central predictions. Here we use maximum-likelihood methods to test for Lévy patterns in relation to environmental gradients in the largest animal movement data set assembled for this purpose. Strong support was found for Lévy search patterns across 14 species of open-ocean predatory fish (sharks, tuna, billfish and ocean sunfish), with some individuals switching between Lévy and Brownian movement as they traversed different habitat types. We tested the spatial occurrence of these two principal patterns and found Lévy behaviour to be associated with less productive waters (sparser prey) and Brownian movements to be associated with productive shelf or convergence-front habitats (abundant prey). These results are consistent with the Lévy-flight foraging hypothesis, supporting the contention that organism search strategies naturally evolved in such a way that they exploit optimal Lévy patterns.

Accelerated fluctuation analysis by graphic cards and complex pattern formation in financial markets

International Nuclear Information System (INIS)

Preis, Tobias; Virnau, Peter; Paul, Wolfgang; Schneider, Johannes J

2009-01-01

The compute unified device architecture is an almost conventional programming approach for managing computations on a graphics processing unit (GPU) as a data-parallel computing device. With a maximum number of 240 cores in combination with a high memory bandwidth, a recent GPU offers resources for computational physics. We apply this technology to methods of fluctuation analysis, which includes determination of the scaling behavior of a stochastic process and the equilibrium autocorrelation function. Additionally, the recently introduced pattern formation conformity (Preis T et al 2008 Europhys. Lett. 82 68005), which quantifies pattern-based complex short-time correlations of a time series, is calculated on a GPU and analyzed in detail. Results are obtained up to 84 times faster than on a current central processing unit core. When we apply this method to high-frequency time series of the German BUND future, we find significant pattern-based correlations on short time scales. Furthermore, an anti-persistent behavior can be found on short time scales. Additionally, we compare the recent GPU generation, which provides a theoretical peak performance of up to roughly 10 12 floating point operations per second with the previous one.

Differences in meal patterns and timing with regard to central obesity in the ANIBES ('Anthropometric data, macronutrients and micronutrients intake, practice of physical activity, socioeconomic data and lifestyles in Spain') Study.

Science.gov (United States)

Aparicio, Aránzazu; Rodríguez-Rodríguez, Elena E; Aranceta-Bartrina, Javier; Gil, Ángel; González-Gross, Marcela; Serra-Majem, Lluis; Varela-Moreiras, Gregorio; Ortega, Rosa Maria

2017-09-01

To study the association of meal patterns and timing with central obesity to identify the best dietary strategies to deal with the increasing obesity prevalence. A cross-sectional study performed on data from a representative sample of the Spanish population. Height and waist circumference were measured using standardized procedures and waist-to-height ratio (WHtR) was calculated. The sample was divided into those without central obesity (WHtRmacronutrients and micronutrients intake, practice of physical activity, socioeconomic data and lifestyles in Spain') Study. Adults aged 18-64 years (n 1655; 798 men and 857 women). A higher percentage of people ate more than four meals daily in the group without central obesity and those with central obesity more frequently skipped the mid-afternoon snack than those without. Breakfasts containing >25 % of total energy intake and lunches containing >35 % of total energy intake were associated with increased likelihood of central obesity (OR=1·874, 95 % CI 1·019, 3·448; P15 % of total energy were associated with decreased likelihood of central obesity (OR=0·477, 95 % CI 0·313, 0·727; P<0·001 and OR=0·650, 95 % CI 0·453, 0·932; P<0·05, respectively). The variety of cereals, wholegrain cereals and dairy was higher in the population without central obesity. Our results suggest that 'what and when we eat' should be considered dietary strategies to reduce central obesity.

ANALYSIS OF EROSION AND SEDIMENTATION PATTERNS USING SOFTWARE OF MIKE 21 HDFM-MT IN THE KAPUAS MURUNG RIVER MOUTH CENTRAL KALIMANTAN PROVINCE

Directory of Open Access Journals (Sweden)

Franto Novico

2017-07-01

Full Text Available The public transportation system along the Kapuas River, Central Kalimantan are highly depend on water transportation. Natural condition gives high distribution to the smoothness of the vessel traffic along the Kapuas Murung River. The local government has planned to build specific port for stock pile at the Batanjung which would face with natural phenomena of sedimentation and erosion at a river mouth. Erosion and sedimentation could be predicted not only by field observing but it is also needed hypotheses using software analysis. Hydrodynamics and transport sediment models by Mike 21 HDFM-MT software will be applied to describe the position of sedimentations and erosions at a river mouth. Model is assumed by two different river conditions, wet and dry seasons. Based on two types of conditions the model would also describe the river flow and sediment transport at spring and neap periods. Tidal fluctuations and a river current as field observation data would be verified with the result of model simulations. Based on field observation and simulation results could be known the verification of tidal has an 89.74% correlation while the river current correlation has 43.6%. Moreover, based on the simulation the sediment patterns in flood period have a larger area than ebb period. Furthermore, the erosion patterns dominantly occur during wet and dry season within ebb period. Water depths and sediment patterns should be considered by the vessels that will use the navigation channel at a river mouth.

Evaluation Of Hydraulic Potentiality For The Generation Of Hydroelectric To Small Scale In The Basin Of The CHICAMOCHA River - Small Hydroelectric Centrals

International Nuclear Information System (INIS)

Pacheco P, Claudia M.; Parga C, Gloria M.

1995-01-01

In development of the agreement of technical and scientific cooperation established between the INEA and the Catholic University of Colombia, the program of Evaluation of Hydraulic Potentiality for Small Central was developed, whose purpose is to take the service to smaller population and villages of all the towns of the country. To begin the program the area corresponding to the basin of Chicamocha river was selected, since this region that corresponds to 72 towns of Boyaca and Santander, has good information, thanks to the diagnosis carried out by the Inderena with the purpose of formulating a Plan of Classification and Handling of the Basin. The work consisted on the identification of all the micro basins, the analysis of the demand of energy of the settled population, to evaluate the generating capacity of the flows of water and, according to the results, to propose alternatives for the design of small hydroelectric centrals (PCH) in accordance with the needs

Diversity of Salmonella isolates from central Florida surface waters.

Science.gov (United States)

McEgan, Rachel; Chandler, Jeffrey C; Goodridge, Lawrence D; Danyluk, Michelle D

2014-11-01

Identification of Salmonella serotypes is important for understanding the environmental diversity of the genus Salmonella. This study evaluates the diversity of Salmonella isolates recovered from 165 of 202 Central Florida surface water samples and investigates whether the serotype of the environmental Salmonella isolates can be predicted by a previously published multiplex PCR assay (S. Kim, J. G. Frye, J. Hu, P. J. Fedorka-Cray, R. Gautom, and D. S. Boyle, J. Clin. Microbiol. 44:3608-3615, 2006, http://dx.doi.org/10.1128/JCM.00701-06). Multiplex PCR was performed on 562 Salmonella isolates (as many as 36 isolates per water sample) to predict serotypes. Kauffmann-White serogrouping was used to confirm multiplex PCR pattern groupings before isolates were serotyped, analyzed by pulsed-field gel electrophoresis, and assayed for antimicrobial susceptibility. In 41.2% of the Salmonella-positive water samples, all Salmonella isolates had identical multiplex PCR patterns; in the remaining 58.8%, two or more multiplex PCR patterns were identified. Within each sample, isolates with matching multiplex PCR patterns had matching serogroups. The multiplex patterns of 495 isolates (88.1%) did not match any previously reported pattern. The remaining 68 isolates matched reported patterns but did not match the serotypes for those patterns. The use of the multiplex PCR allowed the number of isolates requiring further analysis to be reduced to 223. Thirty-three Salmonella enterica serotypes were identified; the most frequent included serotypes Muenchen, Rubislaw, Anatum, Gaminara, and IV_50:z4,z23:-. A majority (141/223) of Salmonella isolates clustered into one genotypic group. Salmonella isolates in Central Florida surface waters are serotypically, genotypically, and phenotypically (in terms of antimicrobial susceptibility) diverse. While isolates could be grouped as different or potentially the same using multiplex PCR, the multiplex PCR pattern did not predict the Salmonella

Categorizing Pedagogical Patterns by Teaching Activities and Pedagogical Value

DEFF Research Database (Denmark)

Eriksen, Ole

2006-01-01

The main contribution of this paper is a proposal for a universal pedagogical pattern categorization based on teaching values and activities. This categorization would be more sustainable than the arbitrary categorization implied by pedagogical pattern language themes. Pedagogical patterns from two...... central patterns languages are analyzed and categorized, and the result is a catalogue theoretically founded and practical in its application. The teaching values are derived from learning theories, implying the theoretical foundation of the catalogue. In order to increase the usability of the value...

Intracranial calcification in central diabetes insipidus

International Nuclear Information System (INIS)

Al-Kandari, Salwa R.; Pandey, Tarun; Badawi, Mona H.

2008-01-01

Intracranial calcification is a known but extremely rare complication of diabetes insipidus. To date, only 16 patients have been reported and all had the peripheral (nephrogenic) type of diabetes insipidus. We report a child with intracranial calcification complicating central diabetes insipidus. We also report a child with nephrogenic diabetes insipidus, and compare the patterns of intracranial calcification. (orig.)

Intracranial calcification in central diabetes insipidus

Energy Technology Data Exchange (ETDEWEB)

Al-Kandari, Salwa R. [Al Razi Hospital, Department of Clinical Radiology, Kuwait (Kuwait); Pandey, Tarun [Al Razi Hospital, Department of Clinical Radiology, Kuwait (Kuwait); University of Arkansas for Medical Sciences, Radiology Department, Little Rock, AR (United States); Badawi, Mona H. [Al-Adan Hospital, Department of Paediatrics, Kuwait (Kuwait)

2008-01-15

Intracranial calcification is a known but extremely rare complication of diabetes insipidus. To date, only 16 patients have been reported and all had the peripheral (nephrogenic) type of diabetes insipidus. We report a child with intracranial calcification complicating central diabetes insipidus. We also report a child with nephrogenic diabetes insipidus, and compare the patterns of intracranial calcification. (orig.)

The fractional patterns of polybrominated diphenyl ethers in the soil of the central Tibetan Plateau, China: The influence of soil components

International Nuclear Information System (INIS)

Yuan Guoli; Xie Wei; Che Xiaochao; Han Peng; Liu Chen; Wang Genhou

2012-01-01

Sixteen soil samples were collected from the central Tibetan Plateau (CTP). The soil concentrations of polybrominated diphenyl ethers (PBDEs) in CTP were analyzed. The detected 42 congeners were divided into light, intermediate and heavy fractions. In addition to the various minerals, other soil properties were also characterized, including the content of soil organic carbon (SOC) and the particle size distribution. The clay content is positively related to the intermediate fraction of the PBDEs and negatively related to the light and heavy fractions. Similar correlations were observed for SOC and the fine-particle fraction (size 2 ) associated with a linear regression indicated that the clays were more highly correlated with the fractional pattern of the PBDEs than with the other properties, such as SOC and the fine-particle fraction. The values of r 2 between clays and three fractions of PBDEs are 0.70, 0.69 and 0.58. Highlights: ► All data about soil and PBDEs were based on field data rather than experiments. ► The intermediate fraction of PBDEs increased with increases in the clay content. ► The clays were more strongly correlated with PBDEs fractional patterns than SOC. - Certain minerals, such as clays, have a greater impact on the adsorption of POPs than SOC in certain areas.

Separation of spatial-temporal patterns ('climatic modes') by combined analysis of really measured and generated numerically vector time series

Science.gov (United States)

Feigin, A. M.; Mukhin, D.; Volodin, E. M.; Gavrilov, A.; Loskutov, E. M.

2013-12-01

The new method of decomposition of the Earth's climate system into well separated spatial-temporal patterns ('climatic modes') is discussed. The method is based on: (i) generalization of the MSSA (Multichannel Singular Spectral Analysis) [1] for expanding vector (space-distributed) time series in basis of spatial-temporal empirical orthogonal functions (STEOF), which makes allowance delayed correlations of the processes recorded in spatially separated points; (ii) expanding both real SST data, and longer by several times SST data generated numerically, in STEOF basis; (iii) use of the numerically produced STEOF basis for exclusion of 'too slow' (and thus not represented correctly) processes from real data. The application of the method allows by means of vector time series generated numerically by the INM RAS Coupled Climate Model [2] to separate from real SST anomalies data [3] two climatic modes possessing by noticeably different time scales: 3-5 and 9-11 years. Relations of separated modes to ENSO and PDO are investigated. Possible applications of spatial-temporal climatic patterns concept to prognosis of climate system evolution is discussed. 1. Ghil, M., R. M. Allen, M. D. Dettinger, K. Ide, D. Kondrashov, et al. (2002) "Advanced spectral methods for climatic time series", Rev. Geophys. 40(1), 3.1-3.41. 2. http://83.149.207.89/GCM_DATA_PLOTTING/GCM_INM_DATA_XY_en.htm 3. http://iridl.ldeo.columbia.edu/SOURCES/.KAPLAN/.EXTENDED/.v2/.ssta/

Airflow Pattern Genereated by Three Air Diffusers

DEFF Research Database (Denmark)

Olmedo, Inés; Nielsen, Peter V.; de Adana, Manuel Ruiz

The correct description of air diffusers plays a crucial role in the CFD predictions of the airflow pattern into a room. The numerical simulation of air distribution in an indoor space is challenging because of the complicated airflow pattern generated. An experimental study has been carried out...... in a full scale test room, 4.10 m (length), 3.20 m (width), and 2.70 m (height), in order to take velocity measurements of the airflow pattern generated by three different air diffusers: displacement, mixing and a low impulse diffuser. Smoke visualization has been developed to determine the direction...

The central responsiveness of the acute cerveau isolé rat.

Science.gov (United States)

User, P; Gottesmann, C

1982-01-01

The electrophysiological patterns of the frontal cortex and dorsal hippocampus were studied in the acute cerveau isolé rat. Central and peripheral stimulations were performed in order to modulate these patterns. The results showed that the permanent alternation of high amplitude spindle bursts and low voltage activity in the anterior neocortex of the acute cerveau isolé was influenced neither by olfactory nor by posterior hypothalamic stimulation. In contrast, these two kinds of stimulation easily modulated the continuous low frequency theta rhythm, recorded in the dorsal hippocampus, in terms of amplitude and in overall frequency. This modulation of the theta rhythm in the acute cerveau isolé rat mimics the changes observed when the normal rat comes from the intermediate stage of sleep (as characterized in the the acute intercollicular transected rat by high amplitude spindle bursts at frontal cortex level and low frequency theta activity in the dorsal hippocampus) to rapid sleep. These results further suggest that, during the intermediate stage (as in the cerveau isolé preparation), the hippocampus montonous theta activity appears through a brainstem disinhibitory process releasing the forebrain limbic pacemaker(s). During the following rapid sleep phase, the theta rhythm would be modulated by pontine activity influences acting on the theta generators.

Regulation of DNA Methylation Patterns by CK2-Mediated Phosphorylation of Dnmt3a

Directory of Open Access Journals (Sweden)

Rachel Deplus

2014-08-01

Full Text Available DNA methylation is a central epigenetic modification that is established by de novo DNA methyltransferases. The mechanisms underlying the generation of genomic methylation patterns are still poorly understood. Using mass spectrometry and a phosphospecific Dnmt3a antibody, we demonstrate that CK2 phosphorylates endogenous Dnmt3a at two key residues located near its PWWP domain, thereby downregulating the ability of Dnmt3a to methylate DNA. Genome-wide DNA methylation analysis shows that CK2 primarily modulates CpG methylation of several repeats, most notably of Alu SINEs. This modulation can be directly attributed to CK2-mediated phosphorylation of Dnmt3a. We also find that CK2-mediated phosphorylation is required for localization of Dnmt3a to heterochromatin. By revealing phosphorylation as a mode of regulation of de novo DNA methyltransferase function and by uncovering a mechanism for the regulation of methylation at repetitive elements, our results shed light on the origin of DNA methylation patterns.

US central station nuclear electric generating units: significant milestones

International Nuclear Information System (INIS)

1979-09-01

Listings of US nuclear power plants include significant dates, reactor type, owners, and net generating capacity. Listings are made by state, region, and utility. Tabulations of status, schedules, and orders are also presented

Hybrid centralized-distributed power conditioning system for thermoelectric generator with high energy efficiency

DEFF Research Database (Denmark)

Wu, Hongfei; Sun, Kai; Chen, Min

2013-01-01

the proposed system, which benefits for implementing high MPPT efficiency and high conversion efficiency simultaneously. A hybrid MPPT control strategy is proposed for this HCD power conditioning system. The characteristics, circuit implementation and operation principles of the proposed system are presented......-distributed (HCD) power conditioning system for TEG and its control strategy are proposed in this paper. The HCD power conditioning system is composed by a centralized power conversion stage and multiple distributed power conversion stages. Most of the power is processed by the centralized power conversion stage...

PatternCoder: A Programming Support Tool for Learning Binary Class Associations and Design Patterns

Science.gov (United States)

Paterson, J. H.; Cheng, K. F.; Haddow, J.

2009-01-01

PatternCoder is a software tool to aid student understanding of class associations. It has a wizard-based interface which allows students to select an appropriate binary class association or design pattern for a given problem. Java code is then generated which allows students to explore the way in which the class associations are implemented in a…

Centrality metrics and localization in core-periphery networks

International Nuclear Information System (INIS)

Barucca, Paolo; Lillo, Fabrizio; Tantari, Daniele

2016-01-01

Two concepts of centrality have been defined in complex networks. The first considers the centrality of a node and many different metrics for it have been defined (e.g. eigenvector centrality, PageRank, non-backtracking centrality, etc). The second is related to large scale organization of the network, the core-periphery structure, composed by a dense core plus an outlying and loosely-connected periphery. In this paper we investigate the relation between these two concepts. We consider networks generated via the stochastic block model, or its degree corrected version, with a core-periphery structure and we investigate the centrality properties of the core nodes and the ability of several centrality metrics to identify them. We find that the three measures with the best performance are marginals obtained with belief propagation, PageRank, and degree centrality, while non-backtracking and eigenvector centrality (or MINRES [10], showed to be equivalent to the latter in the large network limit) perform worse in the investigated networks. (paper: interdisciplinary statistical mechanics )

Changing seasonality patterns in Central Europe from Miocene Climate Optimum to Miocene Climate Transition deduced from the Crassostrea isotope archive

Science.gov (United States)

Harzhauser, Mathias; Piller, Werner E.; Müllegger, Stefan; Grunert, Patrick; Micheels, Arne

2011-03-01

The Western Tethyan estuarine oyster Crassostrea gryphoides is an excellent climate archive due to its large size and rapid growth. It is geologically long lived and allows a stable isotope-based insight into climatic trends during the Miocene. Herein we utilised the climate archive of 5 oyster shells from the Miocene Climate Optimum (MCO) and the subsequent Miocene Climate Transition (MCT) to evaluate changes of seasonality patterns. MCO shells exhibit highly regular seasonal rhythms of warm-wet and dry-cool seasons. Optimal conditions resulted in extraordinary growth rates of the oysters. δ 13C profiles are in phase with δ 18O although phytoplankton blooms may cause a slight offset. Estuarine waters during the MCO in Central Europe display a seasonal temperature range of c. 9-10 °C. Absolute water temperatures have ranged from 17 to 19 °C during cool seasons and up to 28 °C in warm seasons. Already during the early phase of the MCO, the growth rates are distinctly declining, although gigantic and extremely old shells have been formed at that time. Still, a very regular and well expressed seasonality is dominating the isotope profiles, but episodically occurring extreme climate events influence the environments. The seasonal temperature range is still c. 9 °C but the cool season temperature seems to be slightly lower (16 °C) and the warm season water temperature does not exceed c. 25 °C. In the later MCT at c. 12.5-12.0 Ma the seasonality pattern is breaking down and is replaced by successions of dry years with irregular precipitation events. No correlation between δ 18O and δ 13C is documented maybe due to a suboptimal nutrition level which would explain the low growth rates and small sizes. The amplitude of seasonal temperature range is decreasing to 5-8 °C. No clear cooling trend can be postulated for that time as the winter season water temperatures range from 15 to 20 °C. This may point to unstable precipitation rhythms on a multi-annual to

Expression pattern of the thrombopoietin receptor (Mpl) in the murine central nervous system.

Science.gov (United States)

Ivanova, Anna; Wuerfel, Jens; Zhang, Juan; Hoffmann, Olaf; Ballmaier, Matthias; Dame, Christof

2010-07-28

Thrombopoietin (Thpo) and its receptor (Mpl), which regulate megakaryopoiesis, are expressed in the central nervous system (CNS), where Thpo is thought to exert pro-apoptotic effects on newly generated neurons. Mpl expression has been analysed in brain tissue on transcript level and in cultured primary rat neurons and astrocytes on protein level. Herein, we analysed Mpl expression in the developing and adult murine CNS by immunohistochemistry and investigated the brain of mice with homozygous Mpl deficiency (Mpl-/-) by MRI. Mpl was not detectable at developmental stages E12 to E15 in any resident cells of the CNS. From E18 onwards, robust Mpl expression was found in various brain areas, including cerebral cortex, olfactory bulb, thalamus, hypothalamus, medulla, pons, and the grey matter of spinal cord. However, major developmental changes became obvious: In the subventricular zone of the cerebral cortex Mpl expression occurred only during late gestation, while in the hippocampus Mpl expression was detectable for first time at stage P4. In the white matter of the cerebellum Mpl expression was restricted to the perinatal period. In the adult cerebellum, Mpl expression switched to Purkinje cell. The majority of other Mpl-positive cells were NeuN-positive neurons. None of the cells could be double-labelled with astrocyte marker GFAP. Mpl-/- mice showed no gross abnormalities of the brain. Our data locate Mpl expression to neurons at different subdivisions of the spinal cord, rhombencephalon, midbrain and prosencephalon. Besides neuronal cells Mpl protein is also expressed in Purkinje cells of the adult cerebellum.

Temporal diversification of Central American cichlids

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Hulsey C Darrin

2010-09-01

Full Text Available Abstract Background Cichlid fishes are classic examples of adaptive radiation because of their putative tendency to explosively diversify after invading novel environments. To examine whether ecological opportunity increased diversification (speciation minus extinction early in a species-rich cichlid radiation, we determined if Heroine cichlids experienced a burst of diversification following their invasion of Central America. Results We first reconstructed the Heroine phylogeny and determined the basal node to use as the root of Central American Heroine diversification. We then examined the influence of incomplete taxon sampling on this group's diversification patterns. First, we added missing species randomly to the phylogeny and assessed deviations from a constant rate of lineage accumulation. Using a range of species numbers, we failed to recover significant deviations from a pure-birth process and found little support for an early burst of diversification. Then, we examined patterns of lineage accumulation as nodes were increasingly truncated. We assumed that as we removed more recently diverged lineages that sampling would become more complete thereby increasing the power to detect deviations from a pure-birth model. However, truncation of nodes provided even less support for an early burst of diversification. Conclusions Contrary to expectations, our analyses suggest Heroine cichlids did not undergo a burst of diversification when they invaded from South America. Throughout their history in Central America, Heroine cichlids appear to have diversified at a constant rate.

The role of central bank transparency for guiding private sector forecasts

OpenAIRE

Ehrmann, Michael; Eijffinger, Sylvester C W; Fratzscher, Marcel

2009-01-01

There is a broad consensus in the literature that costs of information processing and acquisition may generate costly disagreements in expectations among economic agents, and that central banks may play a central role in reducing such dispersion in expectations. This paper analyses empirically whether enhanced central bank transparency lowers dispersion among professional forecasters of key economic variables, using a large set of proxies for central bank transparency in 12 advanced economies...

Simulation of the diffraction pattern of one dimensional quasicrystal ...

African Journals Online (AJOL)

In addition, it has been found that each golden mean produces a unique diffraction pattern and that the lower the golden mean the better the diffraction pattern resembles that of a periodic chain. Also the intensity of the central peak was found to decrease as the golden mean increases. However the value of golden mean ...

Report of the Central Tracking Group

International Nuclear Information System (INIS)

Cassel, D.G.; Hanson, G.G.

1986-10-01

Issues involved in building a realistic central tracking system for a general-purpose 4π detector for the SSC are addressed. Such a central tracking system must be capable of running at the full design luminosity of 10 33 cm -2 s -1 . Momentum measurement was required in a general-purpose 4π detector. Limitations on charged particle tracking detectors at the SSC imposed by rates and radiation damage are reviewed. Cell occupancy is the dominant constraint, which led us to the conclusion that only small cells, either wires or straw tubes, are suitable for a central tracking system at the SSC. Mechanical problems involved in building a central tracking system of either wires or straw tubes were studied, and our conclusion was that it is possible to build such a large central tracking system. Of course, a great deal of research and development is required. We also considered central tracking systems made of scintillating fibers or silicon microstrips, but our conclusion was that neither is a realistic candidate given the current state of technology. We began to work on computer simulation of a realistic central tracking system. Events from interesting physics processes at the SSC will be complex and will be further complicated by hits from out-of-time bunch crossings and multiple interactions within the same bunch crossing. Detailed computer simulations are needed to demonstrate that the pattern recognition and tracking problems can be solved

Consumer-generated versus marketer-generated websites in consumer decision making

NARCIS (Netherlands)

Bronner, F.; de Hoog, R.

2010-01-01

Internet users are encouraged to rate and review all kinds of services and products. These kinds of reviews are described as eWOM (electronic wordof- mouth). Our central question is ‘Are consumers using these reviews, and what is the role of eWOM as compared with commercial-marketer-generated

Cancer Control in Central and Eastern Europe

OpenAIRE

La Vecchia, Carlo; Conte, Pierfranco

2016-01-01

In Central and Western Europe, cancer mortality is declining at slower rates as compared with rates in the rest of the world. More than a generation has now passed since the end of nonmarket economies in Central and Eastern Europe. It is time for this area of the continent to close the gap in cancer incidence and mortality rates between it and Western Europe and other high-income areas of the world.

Generation and Detection of Alignments in Gabor Patterns

Directory of Open Access Journals (Sweden)

Samy Blusseau

2016-11-01

Full Text Available This paper presents a method to be used in psychophysical experiments to compare directly visual perception to an a contrario algorithm, on a straight patterns detection task. The method is composed of two parts. The first part consists in building a stimulus, namely an array of oriented elements, in which an alignment is present with variable salience. The second part focuses on a detection algorithm, based on the a contrario theory, which is designed to predict which alignment will be considered as the most salient in a given stimulus.

Analog automatic test pattern generation for quasi-static structural test.

NARCIS (Netherlands)

Zjajo, A.; Pineda de Gyvez, J.

2009-01-01

A new approach for structural, fault-oriented analog test generation methodology to test for the presence of manufacturing-related defects is proposed. The output of the test generator consists of optimized test stimuli, fault coverage and sampling instants that are sufficient to detect the failure

Dietary protein is associated with musculoskeletal health independently of dietary pattern: the Framingham Third Generation Study.

Science.gov (United States)

Mangano, Kelsey M; Sahni, Shivani; Kiel, Douglas P; Tucker, Katherine L; Dufour, Alyssa B; Hannan, Marian T

2017-03-01

Background: Above-average dietary protein, as a single nutrient, improves musculoskeletal health. Evaluating the link between dietary protein and musculoskeletal health from a whole-diet perspective is important, as dietary guidelines focus on dietary patterns. Objective: We examined the prospective association of novel dietary protein food clusters (derived from established dietary pattern techniques) with appendicular lean mass (ALM), quadriceps strength (QS), and bone mineral density (BMD) in 2986 men and women, aged 19-72 y, from the Framingham Third Generation Study. Design: Total protein intake was estimated by food-frequency questionnaire in 2002-2005. A cluster analysis was used to classify participants into mutually exclusive groups, which were determined by using the percentage of contribution of food intake to overall protein intake. General linear modeling was used to 1 ) estimate the association between protein intake (grams per day) and BMD, ALM, appendicular lean mass normalized for height (ALM/ht 2 ), and QS (2008-2011) and to 2 ) calculate adjusted least-squares mean outcomes across quartiles of protein (grams per day) and protein food clusters. Results: The mean ± SD age of subjects was 40 ± 9 y; 82% of participants met the Recommended Daily Allowance (0.8 g · kg body weight -1 · d -1 ). The following 6 dietary protein food clusters were identified: fast food and full-fat dairy, fish, red meat, chicken, low-fat milk, and legumes. BMD was not different across quartiles of protein intake ( P -trend range = 0.32-0.82); but significant positive trends were observed for ALM, ALM/ht 2 ( P dietary protein is associated with ALM and QS but not with BMD. In this study, dietary protein food patterns do not provide further insight into beneficial protein effects on muscle outcomes. © 2017 American Society for Nutrition.

Quantitative evaluation of inhaled radioactive aerosol deposition patterns in the lungs in obstructive airways disease

Energy Technology Data Exchange (ETDEWEB)

Teshima, Takeo; Isawa, Toyoharu; Hirano, Tomio; Ebina, Akio; Shiraishi, Koichiro; Konno, Kiyoshi

1985-12-01

Uneven distribution of inhaled aerosol in the lungs is the characteristics of obstructive airways disease such as chronic bronchitis and pulmonary emphysema, and has been classified typically into peripheral and central deposition patterns, respectively by visual inspection, whereas in the normal the distribution is homogeneous throughout the lungs. The purpose of the present study was to analyse the distribution of inhaled radioactivity in the lungs by way of matrixes by a computer. The seemingly homogeneous distribution pattern in normal subjects has been found to indicate a gradual change in count profile between the neighboring matrixes. The peripheral pattern indicates the patchy presence of small number of matrixes with excessive radioactivity throughout the lungs, and the central pattern, the presence of matrixes of excessive radioactivity along the major central airways forming a comma-like configuration superimposed on the peripheral pattern. Our computer analysis has a potentiality to characterize obstructive airways disease for a better understanding of their pathophysiology, which is not feasible by a simple visual inspection of images on a polaroid picture.

Assessing dissolved methane patterns in central New York groundwater

Directory of Open Access Journals (Sweden)

Lauren E. McPhillips

2014-07-01

New hydrological insights for this region: There was no significant difference between methane concentrations in valleys versus upslope locations, in water wells less than or greater than 1 km from a conventional gas well, and across different geohydrologic units. Methane concentrations were significantly higher in groundwater dominated by sodium chloride or sodium bicarbonate compared with groundwater dominated by calcium bicarbonate, indicating bedrock interactions and lengthy residence times as controls. A multivariate regression model of dissolved methane using only three variables (sodium, hardness, and barium explained 77% of methane variability, further emphasizing the dominance of geochemistry and hydrogeology as controls on baseline methane patterns.

Mining continuous activity patterns from animal trajectory data

Science.gov (United States)

Wang, Y.; Luo, Ze; Baoping, Yan; Takekawa, John Y.; Prosser, Diann J.; Newman, Scott H.

2014-01-01

The increasing availability of animal tracking data brings us opportunities and challenges to intuitively understand the mechanisms of animal activities. In this paper, we aim to discover animal movement patterns from animal trajectory data. In particular, we propose a notion of continuous activity pattern as the concise representation of underlying similar spatio-temporal movements, and develop an extension and refinement framework to discover the patterns. We first preprocess the trajectories into significant semantic locations with time property. Then, we apply a projection-based approach to generate candidate patterns and refine them to generate true patterns. A sequence graph structure and a simple and effective processing strategy is further developed to reduce the computational overhead. The proposed approaches are extensively validated on both real GPS datasets and large synthetic datasets.

An image-processing methodology for extracting bloodstain pattern features.

Science.gov (United States)

Arthur, Ravishka M; Humburg, Philomena J; Hoogenboom, Jerry; Baiker, Martin; Taylor, Michael C; de Bruin, Karla G

2017-08-01

There is a growing trend in forensic science to develop methods to make forensic pattern comparison tasks more objective. This has generally involved the application of suitable image-processing methods to provide numerical data for identification or comparison. This paper outlines a unique image-processing methodology that can be utilised by analysts to generate reliable pattern data that will assist them in forming objective conclusions about a pattern. A range of features were defined and extracted from a laboratory-generated impact spatter pattern. These features were based in part on bloodstain properties commonly used in the analysis of spatter bloodstain patterns. The values of these features were consistent with properties reported qualitatively for such patterns. The image-processing method developed shows considerable promise as a way to establish measurable discriminating pattern criteria that are lacking in current bloodstain pattern taxonomies. Copyright © 2017 Elsevier B.V. All rights reserved.

Gene Mutation Profiles in Primary Diffuse Large B Cell Lymphoma of Central Nervous System: Next Generation Sequencing Analyses

Science.gov (United States)

Todorovic Balint, Milena; Jelicic, Jelena; Mihaljevic, Biljana; Kostic, Jelena; Stanic, Bojana; Balint, Bela; Pejanovic, Nadja; Lucic, Bojana; Tosic, Natasa; Marjanovic, Irena; Stojiljkovic, Maja; Karan-Djurasevic, Teodora; Perisic, Ognjen; Rakocevic, Goran; Popovic, Milos; Raicevic, Sava; Bila, Jelena; Antic, Darko; Andjelic, Bosko; Pavlovic, Sonja

2016-01-01

The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach. PMID:27164089

Comparative phylogeography of Oryzomys couesi and Ototylomys phyllotis; historic and geographic implications for the Central America conformation

Directory of Open Access Journals (Sweden)

Tania Anaid Gutiérrez-García

2013-12-01

Full Text Available Central America is an ideal region for comparative phylogeographic studies because of its intricate geologic and biogeographic history, diversity of habitats and dynamic climatic and tectonic history. The aim of this work was to assess the phylogeography of two rodents codistributed throughout Central America, in order to identify if they show concordant genetic and phylogeographic patterns. The synopsis includes four parts: (1 an overview of the field of comparative phylogeography; (2 a detailed review that describes how genetic and geologic studies can be combined to elucidate general patterns of the biogeographic and evolutionary history of Central America; and a phylogeographic analysis of two species at both the (3 intraspecific and (4 comparative phylogeographic levels. The last incorporates specific ecological features and evaluates their influence on the species’ genetic patterns. Results showed a concordant genetic structure influenced by geographic distance for both rodents, but dissimilar dispersal patterns due to ecological features and life history. 

Autofluorescencia de fondo en pacientes con coriorretinopatía serosa central Fundus autofluorescence in patients with central serous chorioretinopathy

Directory of Open Access Journals (Sweden)

Eva R Santana Alas

2010-01-01

Chorioretinopathy (CSC, and determine the relationship with functional and anatomic disturbances of the macular region. METHODS: Cross-sectional descriptive study performed in 21 eyes (21 patients, suffering from central serous chorioretinopathy in different statings. The pattern of autofluorecense in the neurosensoral detachment was detected with the Heidelberg´s Retinal Angiograph (HRA2 on 30° position. The optical coherence tomography (3D-OCT-Topcon (Nidek measured the central macular thickness and exposed the anatomic changes. Flourescein angiografy with HRA2 was performed on 12 patients. RESULTS: Hypoautofluorescense was detected in 51,90 % and hyperautofluorescense in 42,86 % of cases respectively; both disorders were present in 4,76 % of the patients. There was no significant difference between hyperautofluorecense and hypoautofluorescense as to the best corrected visual acuity (mean of 0,43 and 0,49, respectively; p= 0.184, and the central macular thickness (mean of 371.3 µm and 388.1 µm, respectively; p= 0.867. However, the difference was significant between time of evolution and the pattern of autoflorescence (p= 0.023. In those eyes affected by hyperautofluorescense, the optical coherence tomography allowed observing irregularities on the external layers and on the retinal pigmentary epithelium. The 83,3 % of cases who needed AGF presented with hyperautofluorescense that matched with hypoautofluorescence in the leakage site. CONCLUSIONS: In the central serous chorioretinopathy, different autofluorescense patterns may be found that reflect changes in the external retina and the retinal pigmentary epithelium. The autofluorescense may help to identify the focal diffusion site.

Cash income, intrahousehold cooperative conflict, and child health in central Mozambique.

Science.gov (United States)

Pfeiffer, James

2003-01-01

This study presents qualitative data on individual cash income generation and intrahousehold bargaining in a sample of 100 households in central Mozambique. It is now recognized that intrahousehold resource allocation patterns can be critical determinants of children's health in the developing world. Recently developed "bargaining-power" models suggest that individual incomes are often not pooled in households and that decisions are the result of a bargaining process that involves cooperation and conflict between men and women. Women's income, many believe, is more often spent on child welfare. Development projects should target benefits to women for greater impact on child health. Some argue that households consist of separate, gendered spheres of economic responsibility that intersect through a "conjugal contract" that defines the terms of cooperation. The findings here support the "separate-spheres" depiction of the household and reveal women's subordinated position in the external cash economy, which undermines their intrahousehold bargaining power.

Lithofacies analysis of the Simpson Group in south-central Kansas

International Nuclear Information System (INIS)

Doveton, J.H.; Charpentier, R.R.; Metzger, E.P.

1990-01-01

This book discusses detailed stratigraphy and lithofacies of the oil-productive Middle Ordovician Simpson Group in south-central Kansas. The report presents results of studies of the Simpson Group in Barber, Comanche, Kiowa, and Pratt counties. The high density of exploration holes and their associated logs allowed a detailed stratigraphic subdivision to be made of shale, sandstone, and sandy carbonate units. The lateral changes in these units are depicted in a series of maps and cross sections and show distinctive lithofacies patterns that reflect a history of northward-moving marine transgression. Working with digital data from gamma-ray logs, the geologists used computer methods to generate a series of cross sections of the Simpson Group, based on the statistical moments of the log traces. Automated mapping displayed the shapes and disposition of shale and non-shale units as continuous features in three dimensions. The ground truth information from drill cuttings further refined interpretations of stratigraphy, lithofacies, and depositional history implied by these computer models

Quantifying traces of tool use: a novel morphometric analysis of damage patterns on percussive tools.