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https://www.readbyqxmd.com/read/29150760/slow-passage-through-a-hopf-bifurcation-in-excitable-nerve-cables-spatial-delays-and-spatial-memory-effects
#1
L M Bilinsky, S M Baer
It is well established that in problems featuring slow passage through a Hopf bifurcation (dynamic Hopf bifurcation) the transition to large-amplitude oscillations may not occur until the slowly changing parameter considerably exceeds the value predicted from the static Hopf bifurcation analysis (temporal delay effect), with the length of the delay depending upon the initial value of the slowly changing parameter (temporal memory effect). In this paper we introduce new delay and memory effect phenomena using both analytic (WKB method) and numerical methods...
November 17, 2017: Bulletin of Mathematical Biology
https://www.readbyqxmd.com/read/29150647/impact-of-multidecadal-climate-variability-on-united-kingdom-rickets-rates
#2
Haris Majeed, G W K Moore
Children who receive inadequate exposure to sunlight have reduced levels of vitamin D, resulting in rickets, a disease that is characterized by bone deformity, stunted growth, and long term pronounced disability. The United Kingdom rickets incidence rates declined from the early 1960's to mid-1990's, after which there was a dramatic increase. The reason for this change is not well understood. Here we show that an important low frequency mode of climate variability, the Atlantic Multidecadal Oscillation (AMO), with a period of ~60-80 years, has an impact on rickets incidence rates in the United Kingdom through changes in sea level pressure, cloud cover and sunshine duration...
November 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29150320/fractional-observer-to-estimate-periodical-forces
#3
A Coronel-Escamilla, J F Gómez-Aguilar, L Torres, R F Escobar-Jimnez, V H Olivares-Peregrino
In the present work we propose a fractional state observer with constant gain to estimate the periodical force exerted on a mechanical system by measuring only its displacement. The state observer is designed from both the Fourier series that approximates the periodical force and the equations of the damped harmonic oscillator that represents the behavior of the system. Specifically, the reconstruction of the force is carried out from the estimates of the series coefficients, which in fact are part of the dynamical system that composes the observer...
November 14, 2017: ISA Transactions
https://www.readbyqxmd.com/read/29149473/exploring-communication-during-the-journey-from-noticing-bodily-changes-to-a-diagnosis-of-endometrial-cancer
#4
Catherine Cook, Margaret Brunton, Tepora Pukepuke, Ai Ling Tan
AIMS AND OBJECTIVES: To understand women's perspectives about the trajectory from first bodily changes to diagnosis. BACKGROUND: With endometrial cancer, as with all gynaecological cancers, early diagnosis is key to successful outcomes. However, women do not always seek clinical advice early. Previously, this gap has been referred to as a 'delay', blamed on fear or refusal to acknowledge symptoms. METHODS: A qualitative research project which involved face-to-face interviews with 16 women who had presented with symptoms of endometrial cancer...
November 17, 2017: Journal of Clinical Nursing
https://www.readbyqxmd.com/read/29149215/longitudinal-survey-of-two-serotine-bat-eptesicus-serotinus-maternity-colonies-exposed-to-eblv-1-european-bat-lyssavirus-type-1-assessment-of-survival-and-serological-status-variations-using-capture-recapture-models
#5
Emmanuelle Robardet, Christophe Borel, Marie Moinet, Dorothée Jouan, Marine Wasniewski, Jacques Barrat, Franck Boué, Elodie Montchâtre-Leroy, Alexandre Servat, Olivier Gimenez, Florence Cliquet, Evelyne Picard-Meyer
This study describes two longitudinal serological surveys of European Bat Lyssavirus type 1 (EBLV-1) antibodies in serotine bat (Eptesicus serotinus) maternity colonies located in the North-East of France. This species is currently considered as the main EBLV-1 reservoir. Multievent capture-recapture models were used to determine the factors influencing bat rabies transmission as this method accounts for imperfect detection and uncertainty in disease states. Considering the period of study, analyses revealed that survival and recapture probabilities were not affected by the serological status of individuals, confirming the capacity of bats to be exposed to lyssaviruses without dying...
November 2017: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/29148713/wireless-acoustic-surface-actuators-for-miniaturized-endoscopes
#6
Tian Qiu, Fabian Adams, Stefano Palagi, Kai Melde, Andrew G Mark, Ulrich Wetterauer, Arkadiusz Miernik, Peer Fischer
Endoscopy enables minimally invasive procedures in many medical fields, such as urology. However, current endoscopes are normally cable-driven, which limits their dexterity and makes them hard to miniaturize. Indeed current urological endoscopes have an outer diameter of about 3 mm and still only possess one bending degree of freedom. In this paper, we report a novel wireless actuation mechanism that increases the dexterity and that permits the miniaturization of a urological endoscope. The novel actuator consists of thin active surfaces that can be readily attached to any device and are wirelessly powered by ultrasound...
November 17, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29147781/a-dft-study-of-a-set-of-natural-dyes-for-organic-electronics
#7
Igo T Lima, Leonardo Sousa, Renato da S Freitas, Luiz Antonio Ribeiro Junior, Rafael Timóteo de Sousa Júnior, Demétrio A da Silva Filho
We systematically investigate, at density functional theory level, the electronic properties of a set of ten carotenoid molecules with different conjugation length. Ground state geometries were fully optimized using both B3LYP and its long-range corrected version, i.e., the CAM-B3LYP functional. The time-dependent DFT approach (TD-DFT) was also performed for the calculation of the excited states of the optimized geometries and the results were compared to the experimental ones, when available. Our findings indicate a dependence of the transition vertical energies, oscillator strengths, and transition dipole moments on the extension of conjugation, as expected...
November 17, 2017: Journal of Molecular Modeling
https://www.readbyqxmd.com/read/29147146/relationships-between-short-and-fast-brain-timescales
#8
Eva Déli, Arturo Tozzi, James F Peters
Brain electric activity exhibits two important features: oscillations with different timescales, characterized by diverse functional and psychological outcomes, and a temporal power law distribution. In order to further investigate the relationships between low- and high- frequency spikes in the brain, we used a variant of the Borsuk-Ulam theorem which states that, when we assess the nervous activity as embedded in a sphere equipped with a fractal dimension, we achieve two antipodal points with similar features (the slow and fast, scale-free oscillations)...
December 2017: Cognitive Neurodynamics
https://www.readbyqxmd.com/read/29147145/long-range-temporal-correlations-of-broadband-eeg-oscillations-for-depressed-subjects-following-different-hemispheric-cerebral-infarction
#9
Dongzhe Hou, Chunfang Wang, Yuanyuan Chen, Weijie Wang, Jingang Du
Abnormal long-range temporal correlation (LRTC) in EEG oscillation has been observed in several brain pathologies and mental disorders. This study examined the relationship between the LRTC of broadband EEG oscillation and depression following cerebral infarction with different hemispheric lesions to provide a novel insight into such depressive disorders. Resting EEGs of 16 channels in 18 depressed (9 left and 9 right lesions) and 21 non-depressed (11 left and 10 right lesions) subjects following cerebral infarction and 19 healthy control subjects were analysed by means of detrended fluctuation analysis, a quantitative measurement of LRTC...
December 2017: Cognitive Neurodynamics
https://www.readbyqxmd.com/read/29146986/cascading-predator-effects-in-a-fijian-coral-reef-ecosystem
#10
Douglas B Rasher, Andrew S Hoey, Mark E Hay
Coral reefs are among Earth's best-studied ecosystems, yet the degree to which large predators influence the ecology of coral reefs remains an open and contentious question. Recent studies indicate the consumptive effects of large reef predators are too diffuse to elicit trophic cascades. Here, we provide evidence that such predators can produce non-consumptive (fear) effects that flow through herbivores to shape the distribution of seaweed on a coral reef. This trophic cascade emerged because reef topography, tidal oscillations, and shark hunting behaviour interact to create predictable "hot spots" of fear on the reef where herbivores withhold feeding and seaweeds gain a spatial refuge...
November 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29146445/interplay-between-daily-rhythmic-serum-mediated-bacterial-killing-activity-and-immune-defence-factors-in-rainbow-trout-oncorhynchus-mykiss
#11
Carlo C Lazado, Manuel Gesto, Lone Madsen, Alfred Jokumsen
Circadian rhythm is emerging as an important regulator of immune functions. However, there is a paucity of information on the influence of this biological phenomenon in the antimicrobial factors in teleost fish. This study investigated the dynamics and interplay of serum-mediated bacterial killing activity and immune defence factors throughout the light:dark (LD) cycle in rainbow trout (Oncorhynchus mykiss). The juvenile fish came from two different emergence time fractions (i.e., late and early) that were believed to exhibit behavioural and physiological differences...
November 13, 2017: Fish & Shellfish Immunology
https://www.readbyqxmd.com/read/29146376/wronger-than-wrong-graded-mapping-of-the-errors-of-an-avatar-in-the-performance-monitoring-system-of-the-onlooker
#12
G Spinelli, G Tieri, E F Pavone, S M Aglioti
EEG studies show that observing errors in one's own or others' actions triggers specific electro-cortical signatures in the onlooker's brain, but whether the brain error-monitoring system operates according to graded or discrete rules is still largely unknown. To explore this issue, we combined immersive virtual reality with EEG recording in participants who observed an avatar reaching-to-grasp a glass from a first-person perspective. The avatar could perform correct or erroneous actions. Erroneous grasps were defined as small or large depending on the magnitude of the trajectory deviation from the to-be-grasped glass...
November 13, 2017: NeuroImage
https://www.readbyqxmd.com/read/29146077/finite-analytic-method-for-modeling-variably-saturated-flows
#13
Zaiyong Zhang, Wenke Wang, Chengcheng Gong, Tian-Chyi Jim Yeh, Zhoufeng Wang, Yu-Li Wang, Li Chen
This paper develops a finite analytic method (FAM) for solving the two-dimensional Richards' equation. The FAM incorporates the analytic solution in local elements to formulate the algebraic representation of the partial differential equation of unsaturated flow so as to effectively control both numerical oscillation and dispersion. The FAM model is then verified using four examples, in which the numerical solutions are compared with analytical solutions, solutions from VSAFT2, and observational data from a field experiment...
November 13, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29145595/synchrony-weather-and-cycles-in-southern-pine-beetle-coleoptera-curculionidae
#14
John D Reeve
Spatial synchrony and cycles are common features of forest insect pests, but are often studied as separate phenomenon. Using time series of timber damage caused by Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae) (southern pine beetle) in 10 states within the southern United States, this study examines synchrony in D. frontalis abundance, the synchronizing effects of temperature extremes, and the evidence for shared cycles among state populations. Cross-correlation and cluster analyses are used to quantify synchrony across a range of geographic distances and to identify groups of states with synchronous dynamics...
November 14, 2017: Environmental Entomology
https://www.readbyqxmd.com/read/29145567/influence-of-airflow-rate-and-stimulus-concentration-on-olfactory-event-related-potentials-oerp-in-humans
#15
Pengfei Han, Valentin A Schriever, Per Peters, Heidi Olze, Florian C Uecker, Thomas Hummel
Although the association between odor concentration and olfactory event-related potential (OERP) has been studied, less is known about the influence of airflow on OERP. The aim of this study was to investigate the influence of airflow rate and stimulus concentration on OERP in humans. EEG data were collected from young healthy volunteers (n=17) in separate sessions where 2-phenylethanol (PEA) was delivered in the following conditions: 8L/min 50%v/v, 8L/min 30%v/v, 4L/min 100%v/v and 4L/min 60%v/v. Odor concentrations are referred to the %v/v achieved with air dilution and was not measured in the nose...
November 14, 2017: Chemical Senses
https://www.readbyqxmd.com/read/29145259/impulse-oscillometry-system-as-an-alternative-diagnostic-method-for-chronic-obstructive-pulmonary-disease
#16
Xia Wei, Zhihong Shi, Yajuan Cui, Jiuyun Mi, Zhengquan Ma, Jingting Ren, Jie Li, Shudi Xu, Youmin Guo
We aimed to compare impulse oscillation system (IOS) and traditional pulmonary function tests (PFTs) for the assessment of the severity of chronic obstructive pulmonary disease (COPD), and to assess the use of IOS parameters to identify patients who were forced expiratory volume in 1 second (FEV1)%pred < 50%.Patients with COPD (n = 215) were enrolled at the Ninth Hospital of Xi'an Affiliated Hospital of Xi'an Jiaotong University between October 2014 and September 2016. All patients were assessed by traditional PFT and IOS...
November 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/29144286/effects-and-mechanistic-aspects-of-absorbing-organic-compounds-by-coking-coal
#17
Kejia Ning, Junfeng Wang, Hongxiang Xu, Xianfeng Sun, Gen Huang, Guowei Liu, Lingmei Zhou
Coal is a porous medium and natural absorbent. It can be used for its original purpose after adsorbing organic compounds, its value does not reduce and the pollutants are recycled, and then through systemic circulation of coking wastewater zero emissions can be achieved. Thus, a novel method of industrial organic wastewater treatment using adsorption on coal is introduced. Coking coal was used as an adsorbent in batch adsorption experiments. The quinoline, indole, pyridine and phenol removal efficiencies of coal adsorption were investigated...
November 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/29143300/effect-of-restraining-the-base-of-support-on-the-other-biomechanical-features-in-patients-with-cerebellar-ataxia
#18
C Conte, Mariano Serrao, L Cuius, A Ranavolo, S Conforto, F Pierelli, L Padua
This study aimed to analyze the biomechanical consequences of reducing the base of support in patients with ataxia. Specifically, we evaluated the spatio-temporal parameters, upper- and lower-body kinematics, muscle co-activation, and energy recovery and expenditure. The gaits of 13 patients were recorded using a motion analysis system in unperturbed and perturbed walking conditions. In the latter condition, patients had to walk using the same step width and speed of healthy controls. The perturbed walking condition featured reduced gait speed, step length, hip and knee range of motion, and energy recovery and increased double support duration, gait variability, trunk oscillation, and ankle joint muscle co-activation...
November 15, 2017: Cerebellum
https://www.readbyqxmd.com/read/29143225/diurnal-regulation-of-the-floral-scent-emission-by-light-and-circadian-rhythm-in-the-phalaenopsis-orchids
#19
Yu-Chen Chuang, Ming-Chi Lee, Ya-Lan Chang, Wen-Huei Chen, Hong-Hwa Chen
BACKGROUND: Phalaenopsis bellina and its closely related species, P. violacea, emit linalool, geraniol and their derivatives as the predominant monoterpenes at the full-bloom stages. Geranyl diphosphate synthase (PbGDPS) is the key enzyme that converts precursors for monoterpene biosynthesis. Besides the monoterpenes being synthesized in concert with floral development stages, we noticed that the scent emission of P. bellina and P. violacea was detected mainly in the daytime. RESULTS: The monoterpenes of P...
November 15, 2017: Botanical Studies (Taipei, Taiwan)
https://www.readbyqxmd.com/read/29143065/-complex-joint-reconstruction-and-joint-transplantation-with-the-flocsat-concept-planning-and-surgical-implementation
#20
REVIEW
C Krettek, J-D Clausen, C Neunaber
Cartilage defects in adult patients are so far incurable. Fresh osteochondral allograft (OCA) transplantation is based on the insertion of mature, living, mechanically sound hyaline cartilage into an osteochondral defect where it undergoes osseointegration. Intact hyaline cartilage of OCA does not cause immune reactions in the recipient. Many reports show that small OCA have good osseointegration and show good long-term results. These observations have been incorporated into the development of the fresh large (> 10 cm(2)) osteochondral shell allograft transplantation (FLOCSAT) concept, which is based on the following principles: 1) the thickness of the osseous layer should be kept as thin as possible (target < 6-8 mm) so that the transplant remains stable and fixable...
November 2017: Der Unfallchirurg
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