WorldWideScience

Sample records for nicotine-induced rotational behaviour

  1. Dynamic behaviour of a rotating cracked beam

    Science.gov (United States)

    Yashar, Ahmed; Ghandchi-Tehrani, Maryam; Ferguson, Neil

    2016-09-01

    This paper presents a new approach to investigate and analyse the vibrational behaviour of cracked rotating cantilever beams, which can for example represent helicopter or wind turbine blades. The analytical Hamiltonian method is used in modelling the rotating beam and two numerical methods, the Rayleigh-Ritz and FEM, are used to study the natural frequencies and the mode shapes of the intact rotating beams. Subsequently, a crack is introduced into the FE model and simulations are performed to identify the modal characteristics for an open cracked rotating beam. The effect of various parameters such as non-dimensional rotating speed, hub ratio and slenderness ratio are investigated for both the intact and the cracked rotating beam, and in both directions of chordwise and flapwise motion. The veering phenomena in the natural frequencies as a function of the rotational speed and the buckling speed are considered with respect to the slenderness ratio. In addition, the mode shapes obtained for the flapwise vibration are compared using the modal assurance criterion (MAC). Finally, a new three dimensional design chart is produced, showing the effect of crack location and depth on the natural frequencies of the rotating beam. This chart will be subsequently important in identifying crack defects in rotating blades.

  2. Coupler rotation behaviour and its effect on heavy haul trains

    Science.gov (United States)

    Xu, Z. Q.; Ma, W. H.; Wu, Q.; Luo, S. H.

    2013-12-01

    When a locomotive coupler rotates at an angle, the lateral component of the coupler force has an adverse effect on the locomotive's safety, particularly in heavy haul trains. In this paper, a model of a head-mid configuration, a 20,000-t heavy haul train is developed to analyse the rotation behaviour of the locomotive's coupler system and its effect on the dynamic behaviour of such a train's middle locomotive when operating on tangent and curved tracks. The train model includes detailed coupler and draft gear with which to consider the hysteretic characteristics of the rubber draft gear model, the friction characteristics of the coupler knuckles, and the alignment-control characteristics of the coupler shoulder. The results indicate that the coupler's rotation behaviour differs between the tangent and curved tracks, significantly affecting the locomotive's running performance under the braking condition. A larger coupler rotation angle generates a larger lateral component, which increases the wheelset's lateral force and the derailment coefficient. Decreasing the maximum coupler free angle can improve the locomotive's operational performance and safety. Based on these results, the recommended maximum coupler free angle is 4°.

  3. Resveratrol prevents nicotine-induced teratogenesis in cultured mouse embryos

    NARCIS (Netherlands)

    Lin, C.; Yon, J.M.; Jung, A.Y.; Lee, J.G.; Jung, K.Y.; Kang, J.K.; Lee, B.J.; Yun, Y.W.; Nam, S.Y.

    2012-01-01

    Nicotine, a major toxic component in tobacco smoke, leads to severe embryonic damage during organogenesis in embryos. We investigated whether resveratrol would positively influence nicotine-induced teratogenesis in mouse embryos (embryonic day 8.5) cultured for 48 h using a whole embryo culture syst

  4. Adolescent nicotine induces persisting changes in development of neural connectivity.

    Science.gov (United States)

    Smith, Robert F; McDonald, Craig G; Bergstrom, Hadley C; Ehlinger, Daniel G; Brielmaier, Jennifer M

    2015-08-01

    Adolescent nicotine induces persisting changes in development of neural connectivity. A large number of brain changes occur during adolescence as the CNS matures. These changes suggest that the adolescent brain may still be susceptible to developmental alterations by substances which impact its growth. Here we review recent studies on adolescent nicotine which show that the adolescent brain is differentially sensitive to nicotine-induced alterations in dendritic elaboration, in several brain areas associated with processing reinforcement and emotion, specifically including nucleus accumbens, medial prefrontal cortex, basolateral amygdala, bed nucleus of the stria terminalis, and dentate gyrus. Both sensitivity to nicotine, and specific areas responding to nicotine, differ between adolescent and adult rats, and dendritic changes in response to adolescent nicotine persist into adulthood. Areas sensitive to, and not sensitive to, structural remodeling induced by adolescent nicotine suggest that the remodeling generally corresponds to the extended amygdala. Evidence suggests that dendritic remodeling is accompanied by persisting changes in synaptic connectivity. Modeling, electrophysiological, neurochemical, and behavioral data are consistent with the implication of our anatomical studies showing that adolescent nicotine induces persisting changes in neural connectivity. Emerging data thus suggest that early adolescence is a period when nicotine consumption, presumably mediated by nicotine-elicited changes in patterns of synaptic activity, can sculpt late brain development, with consequent effects on synaptic interconnection patterns and behavior regulation. Adolescent nicotine may induce a more addiction-prone phenotype, and the structures altered by nicotine also subserve some emotional and cognitive functions, which may also be altered. We suggest that dendritic elaboration and associated changes are mediated by activity-dependent synaptogenesis, acting in part

  5. Behaviour of Rotating Bose-Einstein Condensates Under Shrinking

    Institute of Scientific and Technical Information of China (English)

    ZHAI Hui; ZHOU Qi

    2005-01-01

    @@ When the repulsive interaction strength between atoms decreases, the size of a rotating Bose-Einstein condensate will consequently shrink. We find that the rotational frequency will increase during the shrinking of condensate,which is a quantum mechanical analogy to ballet dancing. Compared to a non-rotating condensate, the size of a rotating BEC will eventually be satiated at a finite value when the interaction strength is gradually reduced.We also calculate the vortex dynamics induced by the atomic current, and discuss the difference of vortex dynamics in this case and that observed in a recent experiment carried out by the JILA group [Phys. Rev. Lett.90 (2003) 170405].

  6. Improving rotation behaviour of robotic structures for micro-assembly.

    OpenAIRE

    Hériban, David; Thiebault, Arnaud; Gauthier, Michaël; Fortier, Guillaume

    2008-01-01

    International audience; Serial micro-assembly requires high precision robots able to produce translations and rotations to position and orient objects during assembly. In micro-scale, the translation ranges required are typically up to the millimeter and can be obtained with smart devices (piezomotor, etc...). In the other hand, the rotation ranges stay identical to the macroscale (eg. 90°) and require standard guidings like ball bearings which induce disturbances on the linear position. Thus...

  7. Residents' perceptions of their teachers: facilitative behaviour and the learning value of rotations.

    Science.gov (United States)

    Kendrick, S B; Simmons, J M; Richards, B F; Roberge, L P

    1993-01-01

    Despite changes in modern medicine the role of the clinical teacher remains central to medical residents' education and rotations continue to be their dominant educational context. Residents have strong positive feelings for clinical teachers who are perceived as interested in teaching and for those rotations that provide a balance of educational opportunities and patient care responsibilities. Research in residency education has focused on teacher behaviours used to teach medical residents clinical information or patient care skills but has neglected teacher behaviours used to facilitate effective learning relationships with residents. To explore the impact of clinical teachers' use of facilitative behaviours on residents' educational experience, we use concepts stemming from the psychologist Carl Rogers' work previously shown to be associated with positive learning outcomes--empathy, unconditional positive regard, and congruence. These constructs are measured by the use of the four scales of the Barrett-Lennard Relationship Inventory (BLRI)--level of regard, unconditionality of regard, congruence and empathy. Our study measures the correlation between residents' perceptions of clinical teachers' use of facilitative behaviours and residents' evaluation of the learning value of rotations. Thirty-three residents completed the BLRI on a different clinical teacher for each of six monthly rotations. A total of 158 surveys were returned. There were strong positive correlations between three of the BLRI variables and residents' perception of the learning value of rotations. Potential uses of these findings are discussed.

  8. Bending and rotational behaviour of semi-continuous composite beams

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Stresses and deflections were measured in various semi-continuous composite beams.The bending and rotational capacities of the composite connections were measured in terms of beam curvatures and deflections by using two full-scale semi-rigid composite frames with monotonic loadings.The effect of semi-rigid connections on the performance of composite beams with various loadings was compared with predictions and codes.The tests show that the semi-continuous composite beams are more economic and effective than the simple or continuous composite beams.The semi-rigid connections affect the bending capacities and beam deflections,so the connection behavior should be considered in the design of composite beams.Yielding analysis of the steel beam bottom flange has some influence on the deflection calculation of composite beams.

  9. Global stability behaviour for the BEK family of rotating boundary layers

    Science.gov (United States)

    Davies, Christopher; Thomas, Christian

    2016-09-01

    Numerical simulations were conducted to investigate the linear global stability behaviour of the Bödewadt, Ekman, von Kármán (BEK) family of flows, for cases where a disc rotates beneath an incompressible fluid that is also rotating. This extends the work reported in recent studies that only considered the rotating-disc boundary layer with a von Kármán configuration, where the fluid that lies above the boundary layer remains stationary. When a homogeneous flow approximation is made, neglecting the radial variation of the basic state, it can be shown that linearised disturbances are susceptible to absolute instability. We shall demonstrate that, despite this prediction of absolute instability, the disturbance development exhibits globally stable behaviour in the BEK boundary layers with a genuine radial inhomogeneity. For configurations where the disc rotation rate is greater than that of the overlying fluid, disturbances propagate radially outwards and there is only a convective form of instability. This replicates the behaviour that had previously been documented when the fluid did not rotate beyond the boundary layer. However, if the fluid rotation rate is taken to exceed that of the disc, then the propagation direction reverses and disturbances grow while convecting radially inwards. Eventually, as they approach regions of smaller radii, where stability is predicted according to the homogeneous flow approximation, the growth rates reduce until decay takes over. Given sufficient time, such disturbances can begin to diminish at every radial location, even those which are positioned outwards from the radius associated with the onset of absolute instability. This leads to the confinement of the disturbance development within a finitely bounded region of the spatial-temporal plane.

  10. Basolateral amygdala CB1 cannabinoid receptors mediate nicotine-induced place preference.

    Science.gov (United States)

    Hashemizadeh, Shiva; Sardari, Maryam; Rezayof, Ameneh

    2014-06-03

    In the present study, the effects of bilateral microinjections of cannabinoid CB1 receptor agonist and antagonist into the basolateral amygdala (intra-BLA) on nicotine-induced place preference were examined in rats. A conditioned place preference (CPP) apparatus was used for the assessment of rewarding effects of the drugs in adult male Wistar rats. Subcutaneous (s.c.) administration of nicotine (0.2mg/kg) induced a significant CPP, without any effect on the locomotor activity during the testing phase. Intra-BLA microinjection of a non-selective cannabinoid CB1/CB2 receptor agonist, WIN 55,212-2 (0.1-0.5 μg/rat) with an ineffective dose of nicotine (0.1mg/kg, s.c.) induced a significant place preference. On the other hand, intra-BLA administration of AM251 (20-60 ng/rat), a selective cannabinoid CB1 receptor antagonist inhibited the acquisition of nicotine-induced place preference. It should be considered that the microinjection of the same doses of WIN 55,212-2 or AM251 into the BLA, by itself had no effect on the CPP score. The administration of a higher dose of AM251 (60 ng/rat) during the acquisition decreased the locomotor activity of animals on the testing phase. Interestingly, the microinjection of AM251 (20 and 40 ng/rat), but not WIN55,212-2 (0.1-0.5 μg/rat), into the BLA inhibited the expression of nicotine-induced place preference without any effect on the locomotor activity. Taken together, these findings support the possible role of endogenous cannabinoid system of the BLA in the acquisition and the expression of nicotine-induced place preference. Furthermore, it seems that there is a functional interaction between the BLA cannabinoid receptors and nicotine in producing the rewarding effects.

  11. Effects of imperatorin on nicotine-induced anxiety- and memory-related responses and oxidative stress in mice.

    Science.gov (United States)

    Budzynska, Barbara; Boguszewska-Czubara, Anna; Kruk-Slomka, Marta; Skalicka-Wozniak, Krystyna; Michalak, Agnieszka; Musik, Irena; Biala, Grazyna; Glowniak, Kazimierz

    2013-10-02

    The purpose of the reported experiments was to examine the effects of imperatorin [9-[(3-methylbut-2-en-1-yl)oxy]-7H-furo[3,2-g]chromen-7-one] on anxiety and memory-related responses induced by nicotine in mice and their relation to the level of nicotine-induced oxidative stress in brain as well as in the hippocampus and the prefrontal cortex. Male Swiss mice were tested for anxiety in the elevated plus maze test (EPM), and for cognition using passive avoidance (PA) procedures. Imperatorin, purified by high-speed counter-current chromatography from methanol extract of fruits of Angelica officinalis, acutely administered at the doses of 10 and 20mg/kg impaired the anxiogenic effect of nicotine (0.1mg/kg, s.c.). Furthermore, acute injections of subthreshold dose of imperatorin (1mg/kg, i.p.) improved processes of memory acquisition when co-administered with nicotine used at non-active dose of 0.05 mg/kg, s.c. Additionally, repeated administration of imperatorin (1mg/kg, i.p., twice daily, for 6 days) improved different stages of memory processes (both acquisition and consolidation) when injected in combination with non-active dose of nicotine (0.05 mg/kg, s.c.) in the PA task. Oxidative stress was assessed by determination of antioxidant enzymes (glutathione peroxidases (GPx), superoxide dismutase (SOD), glutathione reductase (GR)) activities as well as of malondialdehyde (MDA) concentration in the whole brain, the hippocampus and the prefrontal cortex after repeated administration of imperatorin (1mg/kg, 6 days) and single nicotine injection (0.05 mg/kgs.c.) on the seventh day. The results of our research suggest strong behavioural interaction between imperatorin and nicotine at the level of anxiety- and cognitive-like processes. Furthermore, imperatorin inhibited nicotine-induced changes in examined indicators of oxidative stress, especially in the hippocampus and the cortex.

  12. Effect of periodic fluctuation of soil particle rotation resistance on interface shear behaviour

    Science.gov (United States)

    Ebrahimian, Babak; Noorzad, Asadollah

    2010-06-01

    The interface behaviour between infinite extended narrow granular layer and bounding structure is numerically investigated using finite element method. The micro-polar (Cosserat) continuum approach within the framework of elasto-plasticity is employed to remove the numerical difficulties caused by strain-softening of materials in classical continuum mechanics. Mechanical properties of cohesionless granular soil are described with Lade's model enhanced with polar terms including Cosserat rotations, curvatures and couple stresses via mean grain diameter as the internal length. The main attention of paper is laid on the influence of spatial periodic fluctuation of rotation resistance of soil particles interlocked with the surface of bounding structure on evolution and location of shear band developed inside granular body. The finite element results demonstrate that the location and evolution of shear localization in granular body is strongly affected by prescribed non-uniform micro-polar kinematic boundary conditions along the interface.

  13. Fenofibrate attenuates nicotine-induced vascular endothelial dysfunction in the rat.

    Science.gov (United States)

    Chakkarwar, Vishal Arvind

    2011-01-01

    The study has been designed to investigate the effect of fenofibrate on nicotine-induced vascular endothelial dysfunction (VED) in rats. Nicotine (2 mg/kg/day, i.p., 4 weeks) was administered to produce VED in rats. The development of VED was assessed by employing isolated aortic ring preparation and estimating serum and aortic concentration of nitrite/nitrate. Further, the integrity of vascular endothelium was assessed using the scanning electron microscopy of thoracic aorta. The expression of mRNA for p22phox and eNOS was assessed by using reverse transcriptase-polymerase chain reaction. Serum thiobarbituric acid reactive substances concentration (TBARS) and aortic superoxide anion concentration were estimated to assess oxidative stress. Moreover, the serum lipid profile was assessed by estimating serum cholesterol, triglycerides and high density lipoprotein. The administration of nicotine induces VED by increased oxidative stress, altered lipid profile and impaired the integrity of vascular endothelium as assessed in terms of decrease in expression of mRNA for endothelial nitric oxide synthase (eNOS), impairing the integrity of vascular endothelium and subsequently decreasing serum and aortic nitrite/nitrate and attenuating acetylcholine-induced endothelium dependent relaxation. Further, nicotine produced oxidative stress, assessed in terms of increase in serum TBARS and aortic superoxide anion generation and increase in expression of mRNA for p22phox. Nicotine altered the lipid profile by increasing the serum cholesterol, triglycerides and decreasing the high density lipoprotein. However, treatment with fenofibrate (32 mg/kg, p.o.) markedly prevented nicotine-induced VED by decreasing oxidative stress and improving integrity of vascular endothelium, normalising the altered lipid profile, increasing the concentration of serum and aortic nitrite/nitrate, enhancing the acetylcholine-induced endothelium dependent relaxation and decreasing serum TBARS and aortic

  14. Involvement of vasoactive intestinal polypeptide in nicotine-induced relaxation of the rat gastric fundus

    OpenAIRE

    1997-01-01

    Nicotine-induced relaxation and release of vasoactive intestinal polypeptide (VIP)- and peptide histidine isoleucine (PHI)-like immunoreactivity (LI) were measured in longitudinal muscle strips from the rat gastric fundus.Under non-cholinergic conditions (0.3 μM atropine), nicotine (3–300 μM) produced concentration-dependent relaxations of the 5-hydroxytryptamine (3 μM)-precontracted strips. Under non-adrenergic non-cholinergic (NANC) conditions (0.3 μM atropine+1 μM phentolamine+1 μM nadolol...

  15. Effect of ginseng saponina on nicotine-induced dopamine release in the rat nucleus accumbens and striatum

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Eun [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Shim, In Sop [Kyunghee University, Seoul (Korea, Republic of); Chung, June Key; Lee, Myung Chul [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2002-10-01

    We investigated the effect of ginseng total saponin (GTS) on nicotine-induced dopamine (DA) release in the striatum and nucleus accumbens of freely moving rats using in vivo microdialysis technique. Systemic pretreatment with GTS decreased striatal DA release induced by local infusion of nicotine into the striatum. However, GTS had no effect on the resting levels of extracellular DA in the striatum. GTS also blocked nicotine-induced DA release in the nucleus accumbens. The results of the present study suggest that GTS acts on the DA terminals to prevent DA release induced by nicotine. This may reflect the blocking effect of GTS on behavioral hyperactivity induced by psychostimulants.

  16. Nicotine-induced upregulation of native neuronal nicotinic receptors is caused by multiple mechanisms.

    Science.gov (United States)

    Govind, Anitha P; Walsh, Heather; Green, William N

    2012-02-08

    Nicotine causes changes in brain nicotinic acetylcholine receptors (nAChRs) during smoking that initiate addiction. Nicotine-induced upregulation is the long-lasting increase in nAChR radioligand binding sites in brain resulting from exposure. The mechanisms causing upregulation are not established. Many different mechanisms have been reported with the assumption that there is a single underlying cause. Using live rat cortical neurons, we examined for the first time how exposure and withdrawal of nicotine shape the kinetics of native α4β2-containing nAChR upregulation in real time. Upregulation kinetics demonstrates that at least two different mechanisms underlie this phenomenon. First, a transient upregulation occurs that rapidly reverses, faster than nAChR degradation, and corresponds to nAChR conformational changes as assayed by conformational-dependent, subunit-specific antibodies. Second, a long-lasting process occurs correlating with increases in nAChR numbers caused by decreased proteasomal subunit degradation. Previous radioligand binding measurements to brain tissue have measured the second process and largely missed the first. We conclude that nicotine-induced upregulation is composed of multiple processes occurring at different rates with different underlying causes.

  17. Nitric oxide synthase inhibition ameliorates nicotine-induced sperm function decline in male rats

    Institute of Scientific and Technical Information of China (English)

    IP Oyeyipo; Y Raji; AdeyomboF Bolarinwa

    2015-01-01

    Objective:To evaluate the effects of inhibiting nitric oxide synthase as a means of intervention in nicotine-induced infertility in male rats.Methods:Forty-eight male and thirty female Wistar rats (180-200 g) were randomly assigned to six groups and treated orally for 30 days with saline (control), nicotine (0.5 mg/kg, 1.0 mg/kg) with or without NG Nitro-L-Arginine Methyl Ester (L- NAME, 50 mg/kg). Treated male rats were cohabited with untreated females in ratio 1:2 for fertility studies. Sperm analysis was done by microscopy. Results:There was a significant decrease in the epididymal sperm motility and count after nicotine treatment. However, the percentage of abnormality significantly increased in nicotine treatment groups. Fertility studies revealed that nicotine reduced libido in male rats and decreased litter weight and number delivered by the untreated female during the experiments. Co-treatment with L-NAME effectively reversed the nicotine-mediated alterations in the sperm functional parameters, fertility indexes and hormone when compared to nicotine only.Conclusion: Taken together, the present data indicate the abilities of L-NAME to ameliorate nicotine-induced spermatotoxic effects in male rats via a mechanism dependent on the circulating testosterone level.

  18. Estradiol pretreatment attenuated nicotine-induced endothelial cell apoptosis via estradiol functional membrane receptor.

    Science.gov (United States)

    Wang, Li-li; Zhao, Jian-li; Lau, Wayne-Bond; Zhang, Yan-qing; Qiao, Zhong-dong; Wang, Ya-jing

    2011-06-01

    Cigarette smoking is highly associated with increased cardiovascular disease complications. The female population, however, manifests reduced cardiovascular morbidity. We define nicotine's effect upon human umbilical vein endothelial cells (HUVECs), determine whether estradiol might ameliorate endothelial dysfunction via its membrane estrogen receptor (mER), and attempt to elucidate the underlying mechanisms. Endothelial cells were pretreated with estradiol-BSA and measured resultant ion flux across the cells via the patch clamp technique to assess mER is functionality. Estradiol-BSA administration was associated with 30% decreased nicotine-induced apoptosis and also attenuated nicotine-activated phosphorylation of p38 and ERK. Pretreatment of estradiol-BSA triggered a low calcium influx, suggesting ahead low influx calcium played a critical role in the underlying protective mechanisms of estradiol. Furthermore, this estradiol-BSA protection against apoptosis remained effective in the presence of tamoxifen, an intracellular estrogen receptor (iER) inhibitor. Additionally, tamoxifen did not abolish estradiol-BSA's inhibitory effect upon p38 and ERK's activation, giving evidence to the obligatory role of p38 and ERK signaling in the estradiol-BSA's anti-apoptotic action via mER. Our study provides evidence that nicotine enhances endothelial cell apoptosis, but estrogen exerts anti-apoptotic effect through its functional membrane estrogen receptor. Clinically, the nicotine in cigarettes might contribute to endothelial dysfunction, whereas ambient estradiol may provide cellular protection against nicotine-induced injury through its functional membrane receptor via MAPK pathway downregulation.

  19. Nicotine induces negative energy balance through hypothalamic AMP-activated protein kinase.

    Science.gov (United States)

    Martínez de Morentin, Pablo B; Whittle, Andrew J; Fernø, Johan; Nogueiras, Rubén; Diéguez, Carlos; Vidal-Puig, Antonio; López, Miguel

    2012-04-01

    Smokers around the world commonly report increased body weight after smoking cessation as a major factor that interferes with their attempts to quit. Numerous controlled studies in both humans and rodents have reported that nicotine exerts a marked anorectic action. The effects of nicotine on energy homeostasis have been mostly pinpointed in the central nervous system, but the molecular mechanisms controlling its action are still not fully understood. The aim of this study was to investigate the effect of nicotine on hypothalamic AMP-activated protein kinase (AMPK) and its effect on energy balance. Here we demonstrate that nicotine-induced weight loss is associated with inactivation of hypothalamic AMPK, decreased orexigenic signaling in the hypothalamus, increased energy expenditure as a result of increased locomotor activity, increased thermogenesis in brown adipose tissue (BAT), and alterations in fuel substrate utilization. Conversely, nicotine withdrawal or genetic activation of hypothalamic AMPK in the ventromedial nucleus of the hypothalamus reversed nicotine-induced negative energy balance. Overall these data demonstrate that the effects of nicotine on energy balance involve specific modulation of the hypothalamic AMPK-BAT axis. These targets may be relevant for the development of new therapies for human obesity.

  20. Protective efficacy of folic acid and vitamin B12 against nicotine-induced toxicity in pancreatic islets of the rat

    Directory of Open Access Journals (Sweden)

    Bhattacharjee Ankita

    2015-06-01

    Full Text Available Although cigarette smoking is associated with insulin resistance and an increased risk for type 2 diabetes, few studies have examined the effect of nicotine on the adult endocrine pancreas. In this study, male Wister rats were treated with nicotine (3 mg/kg body weight/day with or without supplementation of folic acid (36 μg/kg body weight/day or vitamin B12 (0.63 μg/kg body weight/day alone or in combination. Fasting blood glucose, insulin and HBA1C level and different oxidative and anti-oxidative stress parameters were measured and pancreatic tissue sections were stained with eosin-haematoxylene. Data were analysed by nonparametric statistics. The results revealed that nicotine induced prediabetes condition with subsequent damage to pancreatic islets in rats. Nicotine also caused oxidative stress in pancreatic tissue as evidenced by increased nitric oxide and malondialdehyde level and decreased superoxide dismutase, catalase and reduced glutathione level. Compared to vitamin B12 supplementation, folic acid blunted the nicotine-induced toxicity in pancreatic islets with higher efficacy. Further, folic acid and vitamin B12 in combination were able to confer significant protection on pancreatic islets against nicotine induced toxicity. These results suggest that supplementation of folic acid and vitamin B12 in combination may be a possible strategy of detoxification against nicotine-induced toxicity in pancreatic islets of the rat.

  1. Protective efficacy of folic acid and vitamin B12 against nicotine-induced toxicity in pancreatic islets of the rat

    Science.gov (United States)

    Bhattacharjee, Ankita; Prasad, Shilpi Kumari; Pal, Swagata; Maji, Bithin; Syamal, Alak Kumar; Banerjee, Arnab

    2015-01-01

    Although cigarette smoking is associated with insulin resistance and an increased risk for type 2 diabetes, few studies have examined the effect of nicotine on the adult endocrine pancreas. In this study, male Wister rats were treated with nicotine (3 mg/kg body weight/ day) with or without supplementation of folic acid (36 μg/kg body weight/day) or vitamin B12 (0.63 μg/kg body weight/day) alone or in combination. Fasting blood glucose, insulin and HBA1C level and different oxidative and anti-oxidative stress parameters were measured and pancreatic tissue sections were stained with eosin-haematoxylene. Data were analysed by nonparametric statistics. The results revealed that nicotine induced prediabetes condition with subsequent damage to pancreatic islets in rats. Nicotine also caused oxidative stress in pancreatic tissue as evidenced by increased nitric oxide and malondialdehyde level and decreased superoxide dismutase, catalase and reduced glutathione level. Compared to vitamin B12 supplementation, folic acid blunted the nicotine-induced toxicity in pancreatic islets with higher efficacy. Further, folic acid and vitamin B12 in combination were able to confer significant protection on pancreatic islets against nicotine induced toxicity. These results suggest that supplementation of folic acid and vitamin B12 in combination may be a possible strategy of detoxification against nicotine-induced toxicity in pancreatic islets of the rat. PMID:27486368

  2. Nicotine-induced expression of low-density lipoprotein receptor in oral epithelial cells.

    Science.gov (United States)

    Ito, Satoshi; Gojoubori, Takahiro; Tsunoda, Kou; Yamaguchi, Yoko; Asano, Masatake; Goke, Eiji; Koshi, Ryosuke; Sugano, Naoyuki; Yoshinuma, Naoto; Komiyama, Kazuo; Ito, Koichi

    2013-01-01

    Nicotine use is one of the most important risk factors for the development of cardiovascular and periodontal diseases. Numerous reports have suggested the possible contribution of disturbed lipid metabolism for the development of both disease groups. Despite these observations, little is known about the relationship between tobacco smoking and the development of these diseases. Our previous microarray data revealed that nicotine induced low-density lipoprotein receptor (LDLR) expression in oral epithelial cells (OECs). The aim of the present study was to confirm nicotine-mediated LDLR induction and to elucidate the signaling mechanisms leading to the augmented expression of LDLR in OECs. LDLR and nicotinic acetylcholine receptor (nAChR) subunit expression was detected by real-time PCR. The production of LDLR was demonstrated by immunofluorescence staining. nAChR-mediated LDLR induction was examined by pre-incubation of the cells with its specific inhibitor, α-bungarotoxin (α-BTX). The functional importance of transcription factor specific protein 1 (Sp1) was examined by luciferase assay, mithramycin pre-incubation or by small interfering RNA (siRNA) transfection. The specific binding of Sp1 to R3 region of LDLR 5'-untranslated region was demonstrated with electrophoretic mobility shift assay (EMSA) and streptavidin-agarose precipitation assay followed by western blotting. The results confirmed that nicotine induced LDLR expression at the transcriptional level. Nicotine was sensed by nAChR and the signal was transduced by Sp1 which bound to the R3 region of LDLR gene. Augmented production of LDLR in the gingival epithelial cells was further demonstrated by immunofluorescence staining using the gingival tissues obtained from the smoking patients. Taken together, the results suggested that nicotine might contribute to the development of both cardiovascular and periodontal diseases by inducing the LDLR in OECs thereby disturbing lipid metabolism.

  3. Nicotine-induced expression of low-density lipoprotein receptor in oral epithelial cells.

    Directory of Open Access Journals (Sweden)

    Satoshi Ito

    Full Text Available BACKGROUND: Nicotine use is one of the most important risk factors for the development of cardiovascular and periodontal diseases. Numerous reports have suggested the possible contribution of disturbed lipid metabolism for the development of both disease groups. Despite these observations, little is known about the relationship between tobacco smoking and the development of these diseases. Our previous microarray data revealed that nicotine induced low-density lipoprotein receptor (LDLR expression in oral epithelial cells (OECs. The aim of the present study was to confirm nicotine-mediated LDLR induction and to elucidate the signaling mechanisms leading to the augmented expression of LDLR in OECs. METHODS AND RESULTS: LDLR and nicotinic acetylcholine receptor (nAChR subunit expression was detected by real-time PCR. The production of LDLR was demonstrated by immunofluorescence staining. nAChR-mediated LDLR induction was examined by pre-incubation of the cells with its specific inhibitor, α-bungarotoxin (α-BTX. The functional importance of transcription factor specific protein 1 (Sp1 was examined by luciferase assay, mithramycin pre-incubation or by small interfering RNA (siRNA transfection. The specific binding of Sp1 to R3 region of LDLR 5'-untranslated region was demonstrated with electrophoretic mobility shift assay (EMSA and streptavidin-agarose precipitation assay followed by western blotting. The results confirmed that nicotine induced LDLR expression at the transcriptional level. Nicotine was sensed by nAChR and the signal was transduced by Sp1 which bound to the R3 region of LDLR gene. Augmented production of LDLR in the gingival epithelial cells was further demonstrated by immunofluorescence staining using the gingival tissues obtained from the smoking patients. CONCLUSIONS: Taken together, the results suggested that nicotine might contribute to the development of both cardiovascular and periodontal diseases by inducing the LDLR in

  4. Estrogen normalizes perinatal nicotine-induced hypertensive responses in adult female rat offspring.

    Science.gov (United States)

    Xiao, Daliao; Huang, Xiaohui; Yang, Shumei; Zhang, Lubo

    2013-06-01

    Perinatal nicotine exposure caused a sex-dependent heightened vascular response to angiotensin II (Ang II) and increased blood pressure in adult male but not in female rat offspring. The present study tested the hypothesis that estrogen normalizes perinatal nicotine-induced hypertensive response to Ang II in female offspring. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps from day 4 of gestation to day 10 after birth. Ovariectomy and 17β-estradiol replacement were performed on 8-week-old female offspring. At 5 months of age, Ang II-induced blood pressure responses were not changed by nicotine treatment in the sham groups. In contrast, nicotine significantly enhanced Ang II-induced blood pressure responses as compared with saline control in the ovariectomy groups, which was associated with increased Ang II-induced vascular contractions. These heightened responses were abrogated by 17β-estradiol replacement. In addition, nicotine enhanced Ang II receptor type I, NADPH (nicotinamide adenine dinucleotide phosphate) oxidase type 2 protein expressions, and reactive oxygen species production of aortas as compared with saline control in the ovariectomy groups. Antioxidative agents, both apocynin and tempol, inhibited Ang II-induced vascular contraction and eliminated the differences of contractions between nicotine-treated and control ovariectomy rats. These findings support a key role of estrogen in the sex difference of perinatal nicotine-induced programming of vascular dysfunction, and suggest that estrogen may counteract heightened reactive oxygen species production, leading to protection of females from development programming of hypertensive phenotype in adulthood.

  5. Nicotine induces fibrogenic changes in human liver via nicotinic acetylcholine receptors expressed on hepatic stellate cells

    Energy Technology Data Exchange (ETDEWEB)

    Soeda, Junpei; Morgan, Maelle; McKee, Chad; Mouralidarane, Angelina; Lin, ChingI [University College London, Centre for Hepatology, Royal Free Hospital, London NW3 2PF (United Kingdom); Roskams, Tania [Department of Morphology and Molecular Pathology, University of Leuven (Belgium); Oben, Jude A., E-mail: j.oben@ucl.ac.uk [University College London, Centre for Hepatology, Royal Free Hospital, London NW3 2PF (United Kingdom); Department of Gastroenterology and Hepatology, Guy' s and St Thomas' Hospital, London SE1 7EH (United Kingdom)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Cigarette smoke may induce liver fibrosis via nicotine receptors. Black-Right-Pointing-Pointer Nicotine induces proliferation of hepatic stellate cells (HSCs). Black-Right-Pointing-Pointer Nicotine activates hepatic fibrogenic pathways. Black-Right-Pointing-Pointer Nicotine receptor antagonists attenuate HSC proliferation. Black-Right-Pointing-Pointer Nicotinic receptor antagonists may have utility as novel anti-fibrotic agents. -- Abstract: Background and aims: Cigarette smoke (CS) may cause liver fibrosis but possible involved mechanisms are unclear. Among the many chemicals in CS is nicotine - which affects cells through nicotinic acetylcholine receptors (nAChR). We studied the effects of nicotine, and involved pathways, on human primary hepatic stellate cells (hHSCs), the principal fibrogenic cells in the liver. We then determined possible disease relevance by assaying nAChR in liver samples from human non-alcoholic steatohepatitis (NASH). Methods: hHSC were isolated from healthy human livers and nAChR expression analyzed - RT-PCR and Western blotting. Nicotine induction of hHSC proliferation, upregulation of collagen1-{alpha}2 and the pro-fibrogenic cytokine transforming growth factor beta 1 (TGF-{beta}1) was determined along with involved intracellular signaling pathways. nAChR mRNA expression was finally analyzed in whole liver biopsies obtained from patients diagnosed with non-alcoholic steatohepatitis (NASH). Results: hHSCs express muscle type ({alpha}1, {beta}1, delta and epsilon) and neuronal type ({alpha}3, {alpha}6, {alpha}7, {beta}2 and {beta}4) nAChR subunits at the mRNA level. Among these subunits, {alpha}3, {alpha}7, {beta}1 and {epsilon} were predominantly expressed as confirmed by Western blotting. Nicotine induced hHSC proliferation was attenuated by mecamylamine (p < 0.05). Additionally, collagen1-{alpha}2 and TGF-{beta}1 mRNA expression were significantly upregulated by nicotine and inhibited by

  6. Protective effects of Mentha spicata against nicotine-induced toxicity in liver and erythrocytes of wistar rats.

    Science.gov (United States)

    Ben Saad, Anouar; Rjeibi, Ilhem; Alimi, Hichem; Ncib, Sana; Bouhamda, Talel; Zouari, Nacim

    2017-09-11

    The aim of this study was to investigate the protective effect of Mentha spicata supplementation against nicotine-induced oxidative damage in the liver and erythrocytes of wistar rats. Bioactive substances were determined by liquid chromatography-electrospray ionization-tandem mass spectrometry analysis. Animals were divided into four groups of six rats each: a normal control group, a nicotine-treated group (1 mg/kg), a group receiving M. spicata extract (100 mg/kg), and a group receiving both M. spicata extract (100 mg/kg) and nicotine (1 mg/kg). Many phenolic acids were identified in the M. spicata aqueous extract. After 2 months treatment, nicotine induced an increase in the level of white blood cells and a marked decrease in erythrocytes, hemoglobin and haematocrit. Aspartate transaminase, alanine transaminase, alkaline phosphatase and lactate dehydrogenase activities were also found to be higher in nicotine-treated group than those of the control one. Furthermore, nicotine-treated rats exhibited oxidative stress, as evidenced by a decrease in antioxidant enzymes activities and an increase in lipid peroxidation level in liver and erythrocytes. Interestingly, the oral administration of M. spicata extract by nicotine-treated rats alleviated such disturbances. M. spicata contained bioactive compounds that possess important antioxidant potential and protected liver and erythrocytes against nicotine-induced damage.

  7. Immunomodulatory Role of Ocimum gratissimum and Ascorbic Acid against Nicotine-Induced Murine Peritoneal Macrophages In Vitro

    Directory of Open Access Journals (Sweden)

    Santanu Kar Mahapatra

    2011-01-01

    Full Text Available The aim of this present study was to evaluate the immune functions and immune responses in nicotine-induced (10 mM macrophages and concurrently establish the immunomodulatory role of aqueous extract of Ocimum gratissimum (Ae-Og and ascorbic acid. In this study, nitrite generations and some phenotype functions by macrophages were studied. Beside that, release of Th1 cytokines (TNF-α, IL-12 and Th2 cytokines (IL-10, TGF-β was measured by ELISA, and the expression of these cytokines at mRNA level was analyzed by real-time PCR. Ae-Og, at a dose of 10 μg/mL, significantly reduced the nicotine-induced NO generation and iNOSII expression. Similar kinds of response were observed with supplementation of ascorbic acid (0.01 mM. The administration of Ae-Og and ascorbic acid increased the decreased adherence, chemotaxis, phagocytosis, and intracellular killing of bacteria in nicotine-treated macrophages. Ae-Og and ascorbic acid were found to protect the murine peritoneal macrophages through downregulation of Th1 cytokines in nicotine-treated macrophages with concurrent activation of Th2 responses. These findings strongly enhanced our understanding of the molecular mechanism leading to nicotine-induced suppression of immune functions and provide additional rationale for application of anti-inflammatory therapeutic approaches by O. gratissimum and ascorbic acid for different inflammatory disease prevention and treatment during nicotine toxicity.

  8. The effects of erdosteine, N-acetylcysteine, and vitamin E on nicotine-induced apoptosis of hippocampal neural cells.

    Science.gov (United States)

    Demiralay, Rezan; Gürsan, Nesrin; Erdem, Havva

    2008-08-01

    This study investigated the frequency of apoptosis in rat hippocampal neural cells after intraperitoneal nicotine injection, examining the roles of the inflammatory markers myeloperoxidase (MPO) and tumor necrosis factor alpha (TNF-alpha) in nicotine-induced brain damage and the protective effects of three known antioxidant agents, N-acetylcysteine (NAC), erdosteine, and vitamin E. Female Wistar rats were divided into seven groups, each composed of nine rats: 2 negative control groups, 2 positive control groups, one erdosteine-treated group (500 mg/kg), one NAC-treated group (500 mg/kg), and one vitamin E-treated group (500 mg/kg). Nicotine was intraperitoneally injected at a dosage of 0.6 mg/kg for 21 days. Following nicotine injection, the antioxidants were administered orally; treatment was continued until the rats were killed. Apoptosis level in hippocampal neural cells was determined by using TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick endlabeling) method. Staining of cytoplasmic TNF-alpha in hippocampal neural cells and hippocampus MPO activity were evaluated by immunohistochemistry. Nicotine administration had no effect on local TNF-alpha production, or hippocampal MPO activity. The treatments with erdosteine, NAC and vitamin E significantly reduced the rate of nicotine-induced hippocampal neural cell apoptosis. This findings suggest that erdosteine and NAC can be as effective as vitamin E in protecting against nicotine-induced hippocampal neural cell apoptosis.

  9. The kappa-opioid receptor is involved in the stimulating effect of nicotine on adrenocortical activity but not in nicotine induced anxiety.

    Science.gov (United States)

    Marco, Eva Maria; Llorente, Ricardo; Pérez-Alvarez, Laura; Moreno, Enrique; Guaza, Carmen; Viveros, Maria Paz

    2005-09-01

    The kappa (kappa) opioid system appears to interact with nicotine in the modulation of locomotion and addiction related processes. In this study we have investigated the possible implication of the kappa-opioid system in the effects of nicotine on anxiety and adrenocortical activity. In two different experiments, we analysed the possible interaction between nicotine (0.5 mg/kg i.p.) and either the kappa-opioid receptor antagonist nor-binaltorphimine (5 mg/kg i.p.) or the kappa-opioid receptor agonist U50,488H (1 mg/kg s.c.). Behavioural and endocrine experiments were performed in different groups of animals. Animals were exposed to the holeboard immediately followed by the plus-maze. Serum corticosterone levels were determined by radioimmunoassay. Nicotine induced an anxiogenic-like effect in the plus-maze and a significant decrease of holeboard activity. The anxiogenic-like effect in the plus-maze was not modified by any of the kappa-opioid receptor ligands. Nicotine also induced a significant increase in the corticosterone levels, and the kappa antagonist, which did not exert any effect per se, antagonised this effect. The kappa-agonist U50,488H induced a significant increase in corticosterone concentration when administered alone. We provide the first evidence for the involvement of the kappa-opioid receptor in the stimulatory effect of nicotine on adrenocortical activity.

  10. Nicotine induces mitochondrial fission through mitofusin degradation in human multipotent embryonic carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Naoya; Yamada, Shigeru [Division of Pharmacology, National Institute of Health Sciences (Japan); Asanagi, Miki [Division of Pharmacology, National Institute of Health Sciences (Japan); Faculty of Engineering, Department of Materials Science and Engineering, Yokohama National University (Japan); Sekino, Yuko [Division of Pharmacology, National Institute of Health Sciences (Japan); Kanda, Yasunari, E-mail: kanda@nihs.go.jp [Division of Pharmacology, National Institute of Health Sciences (Japan)

    2016-02-05

    Nicotine is considered to contribute to the health risks associated with cigarette smoking. Nicotine exerts its cellular functions by acting on nicotinic acetylcholine receptors (nAChRs), and adversely affects normal embryonic development. However, nicotine toxicity has not been elucidated in human embryonic stage. In the present study, we examined the cytotoxic effects of nicotine in human multipotent embryonal carcinoma cell line NT2/D1. We found that exposure to 10 μM nicotine decreased intracellular ATP levels and inhibited proliferation of NT2/D1 cells. Because nicotine suppressed energy production, which is a critical mitochondrial function, we further assessed the effects of nicotine on mitochondrial dynamics. Staining with MitoTracker revealed that 10 μM nicotine induced mitochondrial fragmentation. The levels of the mitochondrial fusion proteins, mitofusins 1 and 2, were also reduced in cells exposed to nicotine. These nicotine effects were blocked by treatment with mecamylamine, a nonselective nAChR antagonist. These data suggest that nicotine degrades mitofusin in NT2/D1 cells and thus induces mitochondrial dysfunction and cell growth inhibition in a nAChR-dependent manner. Thus, mitochondrial function in embryonic cells could be used to assess the developmental toxicity of chemicals.

  11. Layout Optimization for the Dishes Installed on a Rotating Table——The Packing Problem With Equilibrium Behavioural Constraints

    Institute of Scientific and Technical Information of China (English)

    滕弘飞; 孙守林; 葛文海; 钟万勰

    1994-01-01

    The layout optimization for the dishes installed on a rotating table is investigated. This is a packing problem with equilibrium behavioural constraints. To deal with its layout topo-models and initial layout, a mathematical model and heuristic approaches, including the method of model-changing iteration (MCI) and the method of main objects topo-models (MOT), are proposed, with a series of intuitive algorithms embedded in, such as the technique for the search under the initial guess and the strategies for remission of "combinatorial explosion" . The validity and reliability of the proposed algorithms are verified by numerical examples and engineering applications, which could be used in satellite module, multiple spindle box, rotating structure and so on.

  12. Influence of rotational speed during centrifugal casting on sliding wear behaviour of the Al-2Si alloy

    Institute of Scientific and Technical Information of China (English)

    P. G. MUKUNDA; A. SHAILESH RAO; Shrikantha S. RAO

    2009-01-01

    The microstructures and dry sliding wearbehaviour of an Al-2Si alloy cast centrifugally are studied. Results indicate that at optimum speed the cast has a microstructure consisting of uniformly distributed α-Al grains and fine eutectic silicon grains. The cast exhibited better wear resistance compared to the same cast prepared at different rpms. This paper attempts to investigate the influence of the microstructural changes in the Al-2Si alloy by varying the rotational speed of the mould and its combined action on the dry sliding wear behaviour.

  13. Fish oil blunted nicotine-induced vascular endothelial abnormalities possibly via activation of PPARγ-eNOS-NO signals.

    Science.gov (United States)

    Taneja, Gaurav; Mahadevan, Nanjaian; Balakumar, Pitchai

    2013-06-01

    Nicotine exposure is associated with an induction of vascular endothelial dysfunction (VED), a hallmark of various cardiovascular disorders. The present study investigated the effect of fish oil in nicotine-induced experimental VED. VED was assessed by employing isolated aortic ring preparation, estimating aortic and serum nitrite/nitrate, aortic superoxide anion generation, and serum TBARS, and carrying out electron microscopic and histological studies of thoracic aorta. Nicotine (2 mg/kg/day, i.p., 4 weeks) administration produced VED in rats by attenuating acetylcholine-induced endothelium-dependent relaxation in the isolated aortic ring preparation, decreasing aortic and serum nitrite/nitrate concentration, impairing endothelial integrity, and inducing vascular oxidative stress. Treatment with fish oil (2 mL/kg/day p.o., 4 weeks) markedly prevented nicotine-induced endothelial functional and structural abnormalities and oxidative stress. However, administration of GW9662, a selective inhibitor of PPARγ, to a significant degree attenuated fish oil-associated anti-oxidant action and vascular endothelial functional and structural improvements. Intriguingly, in vitro incubation of L-NAME (100 μM), an inhibitor of nitric oxide synthase (NOS), markedly attenuated fish oil-induced improvement in endothelium-dependent relaxation in the aorta of nicotine-administered rats. Nicotine administration altered the lipid profile by increasing serum total cholesterol, which was significantly prevented by fish oil treatment. The vascular protective potential of fish oil in preventing nicotine-induced VED may pertain to its additional properties (besides its lipid-lowering effect) such as activation of PPARγ and subsequent possible activation of endothelial NOS and generation of nitric oxide, and consequent reduction in oxidative stress.

  14. Protective Effect of Antenatal Antioxidant on Nicotine-Induced Heart Ischemia-Sensitive Phenotype in Rat Offspring.

    Science.gov (United States)

    Xiao, DaLiao; Wang, Lei; Huang, Xiaohui; Li, Yong; Dasgupta, Chiranjib; Zhang, Lubo

    2016-01-01

    Fetal nicotine exposure increased risk of developing cardiovascular disease later in life. The present study tested the hypothesis that perinatal nicotine-induced programming of heart ischemia-sensitive phenotype is mediated by enhanced reactive oxygen species (ROS) in offspring. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps from day 4 of gestation to day 10 after birth, in the absence or presence of a ROS inhibitor, N-acetyl-cysteine (NAC) in drinking water. Experiments were conducted in 8 month old age male offspring. Isolated hearts were perfused in a Langendorff preparation. Perinatal nicotine treatment significantly increased ischemia and reperfusion-induced left ventricular injury, and decreased post-ischemic recovery of left ventricular function and coronary flow rate. In addition, nicotine enhanced cardiac ROS production and significantly attenuated protein kinase Cε (PKCε) protein abundance in the heart. Although nicotine had no effect on total cardiac glycogen synthase kinase-3β (GSK3β) protein expression, it significantly increased the phosphorylation of GSK3β at serine 9 residue in the heart. NAC inhibited nicotine-mediated increase in ROS production, recovered PKCε gene expression and abrogated increased phosphorylation of GSK3β. Of importance, NAC blocked perinatal nicotine-induced increase in ischemia and reperfusion injury in the heart. These findings provide novel evidence that increased oxidative stress plays a causal role in perinatal nicotine-induced developmental programming of ischemic sensitive phenotype in the heart, and suggest potential therapeutic targets of anti-oxidative stress in the treatment of ischemic heart disease.

  15. Protective Effect of Antenatal Antioxidant on Nicotine-Induced Heart Ischemia-Sensitive Phenotype in Rat Offspring.

    Directory of Open Access Journals (Sweden)

    DaLiao Xiao

    Full Text Available Fetal nicotine exposure increased risk of developing cardiovascular disease later in life. The present study tested the hypothesis that perinatal nicotine-induced programming of heart ischemia-sensitive phenotype is mediated by enhanced reactive oxygen species (ROS in offspring. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps from day 4 of gestation to day 10 after birth, in the absence or presence of a ROS inhibitor, N-acetyl-cysteine (NAC in drinking water. Experiments were conducted in 8 month old age male offspring. Isolated hearts were perfused in a Langendorff preparation. Perinatal nicotine treatment significantly increased ischemia and reperfusion-induced left ventricular injury, and decreased post-ischemic recovery of left ventricular function and coronary flow rate. In addition, nicotine enhanced cardiac ROS production and significantly attenuated protein kinase Cε (PKCε protein abundance in the heart. Although nicotine had no effect on total cardiac glycogen synthase kinase-3β (GSK3β protein expression, it significantly increased the phosphorylation of GSK3β at serine 9 residue in the heart. NAC inhibited nicotine-mediated increase in ROS production, recovered PKCε gene expression and abrogated increased phosphorylation of GSK3β. Of importance, NAC blocked perinatal nicotine-induced increase in ischemia and reperfusion injury in the heart. These findings provide novel evidence that increased oxidative stress plays a causal role in perinatal nicotine-induced developmental programming of ischemic sensitive phenotype in the heart, and suggest potential therapeutic targets of anti-oxidative stress in the treatment of ischemic heart disease.

  16. INVESTIGATION OF RANDOM RESPONSE OF ROTATIONAL SHELL WHEN CONSIDERING GEOMETRIC NONLINEAR BEHAVIOUR

    Institute of Scientific and Technical Information of China (English)

    GAO Shi-qiao(高世桥); JIN Lei(金磊); H.J.Niemann; LIU Hai-peng(刘海鹏)

    2001-01-01

    An iteration method of statistic linearization (IMSL) is presented. By this method, an equivalent linear term was formed in geometric relation and then an equivalent stiffness matrix for nonlinear term in vibration equation was established. Using the method to solve the statistic linear vibration equations, the effect of geometric nonlinearity on the random response of rotational shell is obtained.

  17. Calcium/calmodulin-dependent protein kinase IV mediates acute nicotine-induced antinociception in acute thermal pain tests.

    Science.gov (United States)

    Jackson, Kia J; Damaj, Mohamad I

    2013-12-01

    Calcium-activated second messengers such as calcium/calmodulin-dependent protein kinase II have been implicated in drug-induced antinociception. The less abundant calcium-activated second messenger, calcium/calmodulin-dependent protein kinase IV (CaMKIV), mediates emotional responses to pain and tolerance to morphine analgesia but its role in nicotine-mediated antinociception is currently unknown. The goal of this study was to evaluate the role of CaMKIV in the acute effects of nicotine, primarily acute nicotine-induced antinociception. CaMKIV knockout (-/-), heterozygote (+/-), and wild-type (+/+) mice were injected with various doses of nicotine and evaluated in a battery of tests, including the tail-flick and hot-plate tests for antinociception, body temperature, and locomotor activity. Our results show a genotype-dependent reduction in tail-flick and hot-plate latency in CaMKIV (+/-) and (-/-) mice after acute nicotine treatment, whereas no difference was observed between genotypes in the body temperature and locomotor activity assessments. The results of this study support a role for CaMKIV in acute nicotine-induced spinal and supraspinal pain mechanisms, and further implicate involvement of calcium-dependent mechanisms in drug-induced antinociception.

  18. Nicotine-induced neurogenic relaxation in the mouse colon: changes with dextran sodium sulfate-induced colitis.

    Science.gov (United States)

    Murakami, Ikuo; Hamada, Yuri; Yamane, Satoshi; Fujino, Hiromichi; Horie, Shunji; Murayama, Toshihiko

    2009-01-01

    Nicotine has been shown to reduce both tone and muscular activity in the human colon by releasing nitric oxide (NO) from nerves. To our knowledge, however, the effect of nicotine on mouse colon has not been elucidated, and the response in tissue from ulcerative colitis (UC) has not been investigated. We examined nicotine-induced responses in colon from control mice and mice with dextran sodium sulfate (DSS)-induced UC. In controls, bath application of nicotine caused a transient relaxation in longitudinal preparations from the transverse and distal colons but not from the rectum. The response was observed in the presence of bethanechol, abolished by treatment with tetrodotoxin and hexamethonium, and mediated partially (>50%) by the NO pathway. In longitudinal preparations of the distal colon from DSS-treated mice, spontaneous contractions decreased markedly, and nicotine caused contraction without relaxation in half of the preparations tested. Nicotine-induced relaxation in the presence of bethanechol was significantly decreased in the DSS-treated distal colon without changing bethanechol-induced contractions. These data suggest that 1) responses to nicotine differ dependent on colon regions, 2) DSS treatment predominantly caused nicotine-sensitive neurogenic changes in distal colon, and 3) DSS treatment may reverse the direction of nicotine-evoked responses in the colon, in mice.

  19. The effects of erdosteine, N-acetylcysteine, and vitamin E on nicotine-induced apoptosis of pulmonary cells.

    Science.gov (United States)

    Demiralay, Rezan; Gürsan, Nesrin; Erdem, Havva

    2006-02-15

    This study was conducted to investigate the frequency of apoptosis in the pulmonary epithelial cells of rats after intratraperitoneal nicotine injection, in order to examine the role of inflammatory markers [myeloperoxidase (MPO) and tumor necrosis factor-alpha (TNF-alpha)] in nicotine-induced lung damage, and to determine the protective effects of three known antioxidant agents [N-acetylcysteine (NAC), erdosteine, and vitamin E] on the lung toxicity of nicotine in the lungs. Female Wistar rats were divided into seven groups, each composed of nine rats: two negative control groups, two positive control groups, one erdosteine-treated group (500 mg/kg), one NAC-treated group (500 mg/kg), and one vitamin E-treated group (500 mg/kg). Nicotine was injected intraperitoneally at a dosage of 0.6 mg/kg for 21 days. Following nicotine injection, the antioxidants were administered orally, treatment was continued until the rats were killed. Lung tissue samples were stained with hematoxylin-eosin (H&E) for histopathological assessments. The apoptosis level in the lung bronchiolar and alveolar epithelium was determined by using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) method. Cytoplasmic TNF-alpha in the bronchiolar and alveolar epithelial cells and the lung MPO activity were evaluated immunohistochemically. The protective effect of vitamin E on lung histology was stronger than that of erdosteine or NAC. Treatment with erdosteine, NAC, and vitamin E significantly reduced the rate of nicotine-induced pulmonary epithelial cell apoptosis, and there were no significant differences in apoptosis among the three antioxidants groups. Erdosteine, NAC, and vitamin E significantly reduced the increases in TNF-alpha staining and lung MPO activity. The effects of erdosteine on the increases in the local TNF-alpha level and lung MPO activity were weaker than that of NAC or vitamin E. This findings suggest that erdosteine and NAC can be as effective as

  20. Cav1.2, but not Cav1.3, L-type calcium channel subtype mediates nicotine-induced conditioned place preference in miceo.

    Science.gov (United States)

    Liu, Yudan; Harding, Meghan; Dore, Jules; Chen, Xihua

    2017-04-03

    Nicotine use is one of the most common forms of drug addiction. Although L-type calcium channels (LTCCs) are involved in nicotine addiction, the contribution of the two primary LTCC subtypes (Cav1.2 and 1.3) is unknown. This study aims to determine the contribution of these two LTCC subtypes to nicotine-induced conditioned place preference (CPP) responses by using transgenic mouse models that do not express Cav1.3 (Cav1.3(-/-)) or contain a mutation in the dihydropyridine (DHP) site of the Cav1.2 (Cav1.2DHP(-/-)). We found a hyperbolic dose dependent nicotine (0.1-1mg/kg; 0.5mg/kg optimum) effect on place preference in wild type (WT) mice, that could be prevented by the DHP LTCC blocker nifedipine pretreatment. Similarly, Cav1.3(-/-) mice showed nicotine-induced place preference which was antagonized by nifedipine. In contrast, nifedipine pretreatment of Cav1.2DHP(-/-) mice had no effect on nicotine-induced CPP responses, suggesting an involvement of Cav1.2 subtype in the nicotine-induced CPP response. Nifedipine alone failed to produce either conditioned place aversion or CPP in WT mice. These results collectively indicate Cav1.2, but not Cav1.3 LTCC subtype regulates, at least in part, the reinforcing effects of nicotine use.

  1. Effects of Discrete Damping on the Dynamic Behaviour of Rotating Shaft through Extended Lagrangian Formulation

    Directory of Open Access Journals (Sweden)

    Rastogi Vikas

    2016-09-01

    Full Text Available The main focus of the paper is touted as effects of discrete damping on the dynamic analysis of rotating shaft. The whole analysis is being carried out through extended Lagrangian formulation for a discrete – continuous system. The variation formulation for this system is possible, considering the continuous system as one-dimensional. The generalized formulation for one dimensional continuous rotary shaft with discrete external damper has been obtained through principle of variation. Using this extended formulation, the invariance of umbra-Lagrangian density through extended Noether’s theorem is achieved. Rayleigh beam model is used to model the shaft. Amplitude equation of rotor is obtained theoretically and validated through simulation results. The simulation results reveal the important phenomena of limiting dynamics of the rotor shaft, which is due to an imbalance of material damping and stiffness of the rotor shaft. The regenerative energy in the rotor shaft, induced due to elasticity/stiffness of the rotor shaft, is dissipated partially through the in-span discrete damper and also through the dissipative coupling between drive and the rotor shaft. In such cases, the shaft speed will not increase with increase in excitation frequency of the rotor but the slip between the drive and the shaft increases due to loading of drive.

  2. Effects of Discrete Damping on the Dynamic Behaviour of Rotating Shaft through Extended Lagrangian Formulation

    Science.gov (United States)

    Rastogi, Vikas

    2016-09-01

    The main focus of the paper is touted as effects of discrete damping on the dynamic analysis of rotating shaft. The whole analysis is being carried out through extended Lagrangian formulation for a discrete - continuous system. The variation formulation for this system is possible, considering the continuous system as one-dimensional. The generalized formulation for one dimensional continuous rotary shaft with discrete external damper has been obtained through principle of variation. Using this extended formulation, the invariance of umbra-Lagrangian density through extended Noether's theorem is achieved. Rayleigh beam model is used to model the shaft. Amplitude equation of rotor is obtained theoretically and validated through simulation results. The simulation results reveal the important phenomena of limiting dynamics of the rotor shaft, which is due to an imbalance of material damping and stiffness of the rotor shaft. The regenerative energy in the rotor shaft, induced due to elasticity/stiffness of the rotor shaft, is dissipated partially through the in-span discrete damper and also through the dissipative coupling between drive and the rotor shaft. In such cases, the shaft speed will not increase with increase in excitation frequency of the rotor but the slip between the drive and the shaft increases due to loading of drive.

  3. The effect of varenicline on the development and expression of nicotine-induced behavioral sensitization and cross-sensitization in rats.

    Science.gov (United States)

    Goutier, Wouter; Kloeze, Margreet B; McCreary, Andrew C

    2015-03-01

    The present study focused on the evaluation of behavioral sensitization and cross-sensitization induced by nicotine and varenicline in rats. Furthermore, it examined the influence of varenicline, a partial alpha4beta2 nicotinic receptor agonist, on nicotine-induced sensitization. To assess the development of behavioral sensitization, rats were chronically treated with vehicle, varenicline (0.03-3.0 mg/kg), nicotine (0.4 mg/kg) or combinations for 5 days and locomotor activity was measured. The expression of sensitization was assessed following a withdrawal period (17-26 days). The present results confirmed previous data showing the development and expression of nicotine-induced sensitization of locomotor activity in the rat. Varenicline did not induce sensitization on its own. When varenicline and nicotine were repeatedly administered sequentially, varenicline blocked the development and expression of nicotine-induced sensitization. Acute varenicline blocked the expression of nicotine-induced sensitization in a dose-dependent manner. Acute varenicline did not significantly increase locomotor activity, nor did it attenuate nicotine-induced sensitization. However, varenicline did cross-sensitize to the effects of nicotine, and vice versa. The present study showed that varenicline produced a dose-dependent bidirectional cross-sensitization with nicotine. Taken together, these findings provide pre-clinical evidence that varenicline is able to attenuate the effects of nicotine, yet simultaneously 'substitutes' for the effects of nicotine in the rat. Longitudinal studies would be needed to see if similar effects are seen in the clinical setting, and whether such effects contribute to the actions of varenicline as a smoking cessation aid.

  4. Nicotine induces self-renewal of pancreatic cancer stem cells via neurotransmitter-driven activation of sonic hedgehog signalling.

    Science.gov (United States)

    Al-Wadei, Mohammed H; Banerjee, Jheelam; Al-Wadei, Hussein A N; Schuller, Hildegard M

    2016-01-01

    A small subpopulation of pancreatic cancer cells with characteristics of stem cells drive tumour initiation, progression and metastasis. A better understanding of the regulation of cancer stem cells may lead to more effective cancer prevention and therapy. We have shown that the proliferation and migration of pancreatic cancer cell lines is activated by the nicotinic receptor-mediated release of stress neurotransmitters, responses reversed by γ-aminobutyric acid (GABA). However, the observed cancer inhibiting effects of GABA will only succeed clinically if GABA inhibits pancreatic cancer stem cells (PCSCs) in addition to the more differentiated cancer cells that comprise the majority of cancer tissues and cell lines. Using PCSCs isolated from two pancreatic cancer patients by cell sorting and by spheroid formation assay from pancreatic cancer cell line Panc-1, we tested the hypothesis that nicotine induces the self-renewal of PCSCs. Nicotinic acetylcholine receptors (nAChRs) α3, α4, α5 and α7 were expressed and chronic exposure to nicotine increased the protein expression of these receptors. Immunoassays showed that PCSCs produced the stress neurotransmitters epinephrine and norepinephrine and the inhibitory neurotransmitter GABA. Chronic nicotine significantly increased the production of stress neurotransmitters and sonic hedgehog (SHH) while inducing Gli1 protein and decreasing GABA. GABA treatment inhibited the induction of SHH and Gli1. Spheroid formation and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoliumbromide assays showed significant nicotine-induced increases in self renewal and cell proliferation, responses blocked by GABA. Our data suggest that nicotine increases the SHH-mediated malignant potential of PCSCs and that GABA prevents these effects.

  5. Aqueous extract ofOcimum gratissimum Linn and ascorbic acid ameliorate nicotine-induced cellular damage in murine peritoneal macrophage

    Institute of Scientific and Technical Information of China (English)

    Santanu Kar Mahapatra; Subhankari Prasad Chakraborty; Somenath Roy

    2010-01-01

    Objective:To test thein vitro protective role of aqueous extract ofOcimum gratissimumLinn. (O. gratissimum) and ascorbic acid against nicotine-induced murine peritoneal macrophage. Methods: Peritoneal macrophages from mice were treated with nicotine (10mM), nicotine (10 mM) with aqueous extract ofO. gratissimum (1 to25 μg/mL), and nicotine (10 mM) with ascorbic acid (0.01 mM) for12h in cell culture media, while the control group was treated with culture media. Levels of free radical generation, lipid peroxidation, protein carbonyls, oxidized glutathione levels andDNA damage were observed and compared.Results:Phytochemical analysis of aqueous extract has shown high amount of phenolics and flavonoids compound present in it. The significantly increased free radical generation, lipid peroxidation, protein carbonyls, oxidized glutathione levels andDNA damage were observed in nicotine-treated group as compared to the control group; those were significantly reduced in aqueous extract ofO. gratissimum and ascorbic acid supplemented groups. Moreover, significantly reduced antioxidant status in nicotine exposed murine peritoneal macrophage was effectively ameliorated by these two products. Among the different concentration of aqueous extract ofO. gratissimum, the maximum protective effect was observed at 10 μg/mL which does not produce any significant change in the normal cell.Conclusions:These findings suggest the potential use and beneficial role ofO. gratissimum as a modulator of nicotine-induced cellular damage in murine peritoneal macrophage.

  6. The effects of erdosteine, N-acetylcysteine and vitamin E on nicotine-induced apoptosis of cardiac cells.

    Science.gov (United States)

    Demiralay, Rezan; Gürsan, Nesrin; Erdem, Havva

    2007-01-01

    This study was conducted to investigate the frequency of apoptosis in rat cardiomyocytes after intratraperitoneal nicotine injection, in order to examine the roles of inflammatory markers [myeloperoxidase (MPO) and tumor necrosis factor alpha (TNF-alpha)] in nicotine-induced cardiac damage and to determine the protective effects of three known antioxidant agents (N-acetylcysteine (NAC), erdosteine and vitamin E) on nicotine toxicity in the heart. Female Wistar rats were divided into seven groups, each composed of nine rats: two negative control groups, two positive control groups, one erdosteine-treated group (500 mg kg(-1)), one NAC-treated group (500 mg kg(-1)) and one vitamin E-treated group (500 mg kg(-1)). Nicotine was intraperitoneally injected at a dosage of 0.6 mg kg(-1) for 21 days. Following nicotine injection, the antioxidants were administered orally; treatment was continued until the rats were killed. Heart tissue samples were stained with hematoxylin-eosin for histopathological assessments. Apoptosis level in cardiomyocytes was determined by using TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick endlabelling) method. Staining of cytoplasmic TNF-alpha in cardiomyocytes and heart MPO activity were evaluated by immunohistochemistry. The treatments with erdosteine, NAC and vitamin E significantly reduced the rate of nicotine-induced cardiomyocyte apoptosis. The effect of vitamin E on apoptosis regulation was weaker than the effects of erdosteine and NAC. Erdosteine, NAC and vitamin E significantly reduced the increases in the local production of TNF-alpha and heart MPO activity. This findings suggest that the effects of erdosteine and NAC on apoptosis regulation are stronger than that of vitamin E.

  7. Calcium-acting drugs modulate expression and development of chronic tolerance to nicotine-induced antinociception in mice.

    Science.gov (United States)

    Damaj, M I

    2005-11-01

    Initial studies in our laboratory suggested that tolerance to nicotine is thought to involve neuronal adaptation not only at the level of the drug-receptor interaction but at postreceptor events such as calcium-dependent second messengers. The present study was undertaken to investigate the hypothesis that L-type calcium channels and calcium-dependent calmodulin protein kinase II are involved in the development and expression of nicotine tolerance. To that end, the effects of modulation of L-type calcium channels (through the use of inhibitors or activators) as well as calcium-dependent calmodulin protein kinase II inactivation were studied in a mouse model of tolerance where mice were infused with nicotine in minipumps (24 mg/kg/day) for 14 days. In addition, the activity of calcium-dependent calmodulin protein kinase II in the lumbar spinal cord region obtained from nicotine-tolerant mice was measured. Our data showed that chronic administration of L-type calcium channel antagonists nimodipine (1 and 5 mg/kg) and verapamil (10 mg/kg) prevented the development of tolerance to nicotine-induced antinociception. In contrast, chronic exposure of BAYK8644 [(+/-)-1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)-phenyl]-3-pyridine carboxylic acid methyl ester], a calcium channel activator, enhanced nicotine's tolerance. Moreover, a significant increase in both dependent and independent calcium-dependent calmodulin protein kinase II activity was seen in the spinal cord in nicotine-tolerant mice. Finally, spinal administration of 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-tyrosyl]-4-phenylpiperazine (KN-62), a calcium-dependent calmodulin protein kinase II antagonist, reduced the expression of tolerance to nicotine-induced antinociception in mice. In conclusion, our data indicate that calcium-dependent mechanisms such as L-type calcium channels and calcium-dependent calmodulin protein kinase II activation are involved in the expression and development of nicotine

  8. Octopamine and Dopamine differentially modulate the nicotine-induced calcium response in Drosophila Mushroom Body Kenyon Cells.

    Science.gov (United States)

    Leyton, V; Goles, N I; Fuenzalida-Uribe, N; Campusano, J M

    2014-02-07

    In Drosophila associative olfactory learning, an odor, the conditioned stimulus (CS), is paired to an unconditioned stimulus (US). The CS and US information arrive at the Mushroom Bodies (MB), a Drosophila brain region that processes the information to generate new memories. It has been shown that olfactory information is conveyed through cholinergic inputs that activate nicotinic acetylcholine receptors (nAChRs) in the MB, while the US is coded by biogenic amine (BA) systems that innervate the MB. In this regard, the MB acts as a coincidence detector. A better understanding of the properties of the responses gated by nicotinic and BA receptors is required to get insights on the cellular and molecular mechanisms responsible for memory formation. In recent years, information has become available on the properties of the responses induced by nAChR activation in Kenyon Cells (KCs), the main neuronal MB population. However, very little information exists on the responses induced by aminergic systems in fly MB. Here we have evaluated some of the properties of the calcium responses gated by Dopamine (DA) and Octopamine (Oct) in identified KCs in culture. We report that exposure to BAs induces a fast but rather modest increase in intracellular calcium levels in cultured KCs. The responses to Oct and DA are fully blocked by a VGCC blocker, while they are differentially modulated by cAMP. Moreover, co-application of BAs and nicotine has different effects on intracellular calcium levels: while DA and nicotine effects are additive, Oct and nicotine induce a synergistic increase in calcium levels. These results suggest that a differential modulation of nicotine-induced calcium increase by DA and Oct could contribute to the events leading to learning and memory in flies.

  9. Alpha5 nicotinic acetylcholine receptor mediates nicotine-induced HIF-1α and VEGF expression in non-small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiaoli; Jia, Yanfei; Zu, Shanshan [Central Laboratory, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013 (China); Li, Ruisheng [Institute of Infectious Diseases, 302 Military Hospital, Beijing 100039 (China); Jia, Ying; Zhao, Yun; Xiao, Dongjie [Central Laboratory, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013 (China); Dang, Ningning [Department of Dermatology, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013 (China); Wang, Yunshan [Central Laboratory, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013 (China)

    2014-07-15

    By binding to nicotinic acetylcholine receptors (nAChRs), nicotine induces the proliferation and apoptosis of non-small cell lung cancer (NSCLC). Previous studies have indicated that α5-nAChR is highly associated with lung cancer risk and nicotine dependence. However, the mechanisms through which α5-nAChRs may influence lung carcinogenesis are far from clear. In the present study, we investigated the roles of α5-nAChR in the nicotine-induced expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). Immunohistochemistry was used to detect the expression of α5-nAChR and HIF-1α in 60 specimens of lung cancer and para-carcinoma tissue. The correlations between the expression levels of α5-nAChR and HIF-1α and other clinicopathological data were analyzed. In a cell line that highly expressed α5-nAChR, the loss of α5-nAChR function by siRNA was used to study whether α5-nAChR is involved in the nicotine-induced expression of HIF-1α and VEGF through the activation of the ERK1/2 and PI3K/Akt signaling pathways. Cell growth was detected using the cell counting kit-8 (CCK-8). α5-nAChR (78.3%) and HIF-1α (88.3%) were both overexpressed in NSCLC, and their expression levels were found to be correlated with each other (P < 0.05). In the A549 cell line, α5-nAChR and HIF-1α were found to be expressed under normal conditions, and their expression levels were significantly increased in response to nicotine treatment. The silencing of α5-nAChR significantly inhibited the nicotine-induced cell proliferation compared with the control group and attenuated the nicotine-induced upregulation of HIF-1α and VEGF, and these effects required the cooperation of the ERK1/2 and PI3K/Akt signaling pathways. These results show that the α5-nAChR/HIF-1α/VEGF axis is involved in nicotine-induced tumor cell proliferation, which suggests that α5-nAChR may serve as a potential anticancer target in nicotine-associated lung cancer. - Highlights

  10. Comparable fMRI activity with differential behavioural performance on mental rotation and overt verbal fluency tasks in healthy men and women.

    Science.gov (United States)

    Halari, Rozmin; Sharma, Tonmoy; Hines, Melissa; Andrew, Chris; Simmons, Andy; Kumari, Veena

    2006-02-01

    To explicate the neural correlates of sex differences in visuospatial and verbal fluency tasks, we examined behavioural performance and blood-oxygenation-level-dependent (BOLD) regional brain activity, using functional magnetic resonance imaging, during a three-dimensional (3D) mental rotation task and a compressed sequence overt verbal fluency task in a group of healthy men (n=9) and women (n=10; tested during the low-oestrogen phase of the menstrual cycle). Men outperformed women on the mental rotation task, and women outperformed men on the verbal fluency task. For the mental rotation task, men and women activated areas in the right superior parietal lobe and the bilateral middle occipital gyrus in association with the rotation condition. In addition, men activated the left middle temporal gyrus and the right angular gyrus. For verbal fluency, men activated areas in the bilateral superior frontal gyrus, right cingulate gyrus, left precentral gyrus, left medial frontal gyrus, left inferior frontal gyrus, thalamus, left parahippocampal gyrus and bilateral lingual gyrus, and women activated areas in the bilateral inferior frontal gyrus and left caudate. Despite observing task related activation in the hypothesised areas in men and women, no areas significantly differentiated the two sexes. Our results demonstrate comparable brain activation in men and women in association with mental rotation and verbal fluency function with differential performance, and provide support for sex differences in brain-behaviour relationships.

  11. Mechanisms involved in systemic nicotine-induced glutamatergic synaptic plasticity on dopamine neurons in the ventral tegmental area.

    Science.gov (United States)

    Gao, Ming; Jin, Yu; Yang, Kechun; Zhang, Die; Lukas, Ronald J; Wu, Jie

    2010-10-13

    Systemic exposure to nicotine induces glutamatergic synaptic plasticity on dopamine (DA) neurons in the ventral tegmental area (VTA), but mechanisms are largely unknown. Here, we report that single, systemic exposure in rats to nicotine (0.17 mg/kg free base) increases the ratio of DA neuronal currents mediated by AMPA relative to NMDA receptors (AMPA/NMDA ratio) assessed 24 h later, based on slice-patch recording. The AMPA/NMDA ratio increase is evident within 1 h and lasts for at least 72 h after nicotine exposure (and up to 8 d after repeated nicotine administration). This effect cannot be prevented by systemic injection of either α7-nAChR (nicotinic ACh receptor)-selective [methyllycaconitine (MLA)] or β2*-nAChR-selective [mecamylamine (MEC)] antagonists but is prevented by coinjection of MLA and MEC. In either nAChR α7 or β2 subunit knock-out mice, systemic exposure to nicotine still increases the AMPA/NMDA ratio. Preinjection in rats of a NMDA receptor antagonist MK-801((+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate), but neither DA receptor antagonists [SCH-23390 (R-(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine) plus haloperidol] nor a calcineurin inhibitor (cyclosporine), prevents the nicotine-induced increase in AMPA/NMDA ratio. After systemic exposure to nicotine, glutamatergic (but not GABAergic) transmission onto rat VTA DA neuronal inputs is enhanced. Correspondingly, DA neuronal firing measured 24 h after nicotine exposure using extracellular single-unit recording in vivo is significantly faster, and there is conversion of silent to active DA neurons. Collectively, these findings demonstrate that systemic nicotine acting via either α7- or β2*-nAChRs increases presynaptic and postsynaptic glutamatergic function, and consequently initiates glutamatergic synaptic plasticity, which may be an important, early neuronal adaptation in nicotine reward and reinforcement.

  12. Calcium homeostasis and protein kinase/phosphatase balance participate in nicotine-induced memory improvement in passive avoidance task in mice.

    Science.gov (United States)

    Michalak, Agnieszka; Biala, Grazyna

    2017-01-15

    Long-term potentiation (LTP) and long-term depression (LTD) depend on specific postsynaptic Ca(2+)/calmodulin concentration. LTP results from Ca(2+) influx through the activated NMDA receptors or voltage-gated calcium channels (VGCCs) and is linked with activation of protein kinases including mitogen-activated protein kinase (MAPK). Weaker synaptic stimulation, as a result of low Ca(2+) influx, leads to activation of Ca(2+)/calmodulin-dependent phosphatase (calcineurin - CaN) and triggers LTD. Interestingly, both memory formation and drug addiction share similar neuroplastic changes. Nicotine, which is one of the most common addictive drugs, manifests its memory effects through nicotinic acetylcholine receptors (nAChRs). Because nAChRs may also gate Ca(2+), it is suggested that calcium signaling pathways are involved in nicotine-induced memory effects. Within the scope of the study was to evaluate the importance of calcium homeostasis and protein kinase/phosphatase balance in nicotine-induced short- and long-term memory effects. To assess memory function in mice passive avoidance test was used. The presented results confirm that acute nicotine (0.1mg/kg) improves short- and long-term memory. Pretreatment with L-type VGCC blockers (amlodipine, nicardipine verapamil) increased nicotine-induced memory improvement in the context of short- and long-term memory. Pretreatment with FK-506 (a potent CaN inhibitor) enhanced short- but not long-term memory effects of nicotine, while SL-327 (a selective MAPK/ERK kinase inhibitor) attenuated both nicotine-induced short- and long-term memory improvement. Acute nicotine enhances both types of memory via L-type VGCC blockade and via ERK1/2 activation. Only short- but not long-term memory enhancement induced by nicotine is dependent on CaN inhibition.

  13. Cannabinoid receptor CB1 is involved in nicotine-induced protection against Aβ1-42 neurotoxicity in HT22 cells.

    Science.gov (United States)

    Wu, Mingchun; Jia, Ji; Lei, Chong; Ji, Ling; Chen, Xiaodan; Sang, Hanfei; Xiong, Lize

    2015-03-01

    Emerging evidences suggest that nicotine exerts a neuroprotective effect on Alzheimer's disease (AD), yet the precise mechanism is not fully elucidated. Here, HT22 cells were exposed to amyloid beta protein fragment (Aβ)1-42 to mimic the pathological process of neuron in AD. We hypothesized that cannabinoid receptor CB1 is involved in the nicotine-induced neuroprotection against Aβ1-42 injury in HT22 cells. CB1 expression in HT22 cells was investigated by immunocytochemistry and Western blot. The injury of HT22 cells was evaluated by cellular morphology, cell viability, and lactate dehydrogenase (LDH) release. The apoptosis of HT22 cells was assessed by flow cytometry and expressions of Bcl-2 and Bax. The results demonstrated that nicotine markedly upregulated CB1 expression, increased cell viability, ameliorated cellular morphology, decreased LDH release, and reduced the apoptotic rate of HT22 cells exposed to Aβ1-42 for 24 h, while the blockade of CB1 or the inhibition of protein kinase C (PKC) partially reversed the neuroprotection. Furthermore, the blockade of CB1 reversed nicotine-induced PKC activation in HT22 cells exposed to Aβ1-42. These results suggest that CB1 is involved in the nicotine-induced neuroprotection against Aβ1-42 neurotoxicity, and the neuroprotection may be dependent on the activation of PKC.

  14. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    Energy Technology Data Exchange (ETDEWEB)

    Zago, A. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Leão, R.M.; Carneiro-de-Oliveira, P.E. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil); Marin, M.T.; Cruz, F.C. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Planeta, C.S. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil)

    2011-11-18

    Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although crosssensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P) 28-37) and adult (P60-67) rats received nicotine (0.4 mg/kg, sc) or saline (0.9% NaCl, sc) and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc) or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

  15. Nicotine-induced place conditioning and locomotor activity in an adolescent animal model of attention deficit/hyperactivity disorder (ADHD).

    Science.gov (United States)

    Watterson, Elizabeth; Daniels, Carter W; Watterson, Lucas R; Mazur, Gabriel J; Brackney, Ryan J; Olive, M Foster; Sanabria, Federico

    2015-09-15

    Attention deficit/hyperactivity disorder (ADHD) is a risk factor for tobacco use and dependence. This study examines the responsiveness to nicotine of an adolescent model of ADHD, the spontaneously hypertensive rat (SHR). The conditioned place preference (CPP) procedure was used to assess nicotine-induced locomotion and conditioned reward in SHR and the Wistar Kyoto (WKY) control strain over a range of nicotine doses (0.0, 0.1, 0.3 and 0.6 mg/kg). Prior to conditioning, SHRs were more active and less biased toward one side of the CPP chamber than WKY rats. Following conditioning, SHRs developed CPP to the highest dose of nicotine (0.6 mg/kg), whereas WKYs did not develop CPP to any nicotine dose tested. During conditioning, SHRs displayed greater locomotor activity in the nicotine-paired compartment than in the saline-paired compartment across conditioning trials. SHRs that received nicotine (0.1, 0.3, 0.6 mg/kg) in the nicotine-paired compartment showed an increase in locomotor activity between conditioning trials. Nicotine did not significantly affect WKY locomotor activity. These findings suggest that the SHR strain is a suitable model for studying ADHD-related nicotine use and dependence, but highlights potential limitations of the WKY control strain and the CPP procedure for modeling ADHD-related nicotine reward.

  16. Beta 2 subunit-containing nicotinic receptors mediate acute nicotine-induced activation of calcium/calmodulin-dependent protein kinase II-dependent pathways in vivo.

    Science.gov (United States)

    Jackson, K J; Walters, C L; Damaj, M I

    2009-08-01

    Nicotine is the addictive component of tobacco, and successful smoking cessation therapies must address the various processes that contribute to nicotine addiction. Thus, understanding the nicotinic acetylcholine receptor (nAChR) subtypes and subsequent molecular cascades activated after nicotine exposure is of the utmost importance in understanding the progression of nicotine dependence. One possible candidate is the calcium/calmodulin-dependent protein kinase II (CaMKII) pathway. Substrates of this kinase include the vesicle-associated protein synapsin I and the transcription factor cAMP response element-binding protein (CREB). The goal of these studies was to examine these postreceptor mechanisms after acute nicotine treatment in vivo. We first show that administration of nicotine increases CaMKII activity in the ventral tegmental area (VTA), nucleus accumbens (NAc), and amygdala. In beta2 nAChR knockout (KO) mice, nicotine does not induce an increase in kinase activity, phosphorylated (p)Synapsin I, or pCREB. In contrast, alpha7 nAChR KO mice show nicotine-induced increases in CaMKII activity and pCREB, similar to their wild-type littermates. Moreover, we show that when animals are pretreated with the CaMKII inhibitors 4-[(2S)-2-[(5-isoquinolinylsulfonyl) methylamino]-3-oxo-3-(4-phenyl-1-piperazinyl)propyl]phenyl isoquinolinesulfonic acid ester (KN-62) and N-[2-[[[3-(4-chlorophenyl)-2 propenyl]methylamino]methyl]phenyl]-N-(2-hydroxyethyl)-4-methoxybenzenesulphonamide (KN-93), nicotine-induced increase in the kinase activity and pCREB was attenuated in the VTA and NAc, whereas pretreatment with (2-[N-(4-methoxybenzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine, phosphate) (KN-92), the inactive analog, did not alter the nicotine-induced increase in pCREB. Taken together, these data suggest that the nicotine-induced increase in CaMKII activity may correlate with the nicotine-induced increase in pSynapsin I and pCREB in the VTA and NAc via beta2

  17. A study of broadband Faraday rotation and polarization behaviour over 1.3--10 GHz in 36 discrete radio sources

    CERN Document Server

    Anderson, C S; Feain, I J

    2016-01-01

    We present a broadband polarization analysis of 36 discrete polarized radio sources over a very broad, densely-sampled frequency band. Our sample was selected on the basis of polarization behaviour apparent in narrowband archival data at 1.4 GHz: half the sample show complicated frequency-dependent polarization behaviour (i.e. Faraday complexity) at these frequencies, while half show comparatively simple behaviour (i.e. they appear Faraday simple). We re-observed the sample using the Australia Telescope Compact Array (ATCA) in full polarization, with 6 GHz of densely sampled frequency coverage spanning 1.3 to 10 GHz. We have devised a general polarization modelling technique that allows us to identify multiple polarized emission components in a source, and to characterize their properties. We detect Faraday complex behaviour in almost every source in our sample. Several sources exhibit particularly remarkable polarization behaviour. By comparing our new and archival data, we have identified temporal variabili...

  18. Inhibition of miRNA-210 reverses nicotine-induced brain hypoxic-ischemic injury in neonatal rats

    Science.gov (United States)

    Wang, Lei; Ke, Jun; Li, Yong; Ma, Qinyi; Dasgupta, Chiranjib; Huang, Xiaohui; Zhang, Lubo; Xiao, DaLiao

    2017-01-01

    Maternal tobacco use in pregnancy increases the risk of neurodevelopmental disorders and neurobehavioral deficits in postnatal life. The present study tested the hypothesis that perinatal nicotine exposure exacerbated brain vulnerability to hypoxic-ischemic (HI) injury in neonatal rats through up-regulation of miR-210 expression in the developing brain. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps. Experiments of HI brain injury were performed in 10-day-old pups. Perinatal nicotine treatment significantly decreased neonatal body and brain weights, but increased the brain to body weight ratio. Perinatal nicotine exposure caused a significant increase in HI brain infarct size in the neonates. In addition, nicotine enhanced miR-210 expression and significantly attenuated brain-derived neurotrophic factor (BDNF) and tropomyosin-related kinase isoform B (TrkB) protein abundance in the brain. Of importance, intracerebroventricular administration of a miR-210 inhibitor (miR-210-LNA) significantly decreased HI-induced brain infarct size and reversed the nicotine-increased vulnerability to brain HI injury in the neonate. Furthermore, miR-210-LNA treatment also reversed nicotine-mediated down-regulation of BDNF and TrkB protein expression in the neonatal brains. These findings provide novel evidence that the increased miR-210 plays a causal role in perinatal nicotine-induced developmental programming of ischemic sensitive phenotype in the brain. It represents a potential novel therapeutic approach for treatment of brain hypoxic-ischemic encephalopathy in the neonate-induced by fetal stress. PMID:28123348

  19. Lipopolysaccharide Enhances the Production of Nicotine-Induced Prostaglandin E2 by an Increase in Cyclooxygenase-2 Expression in Osteoblasts

    Institute of Scientific and Technical Information of China (English)

    Maiko SHOJI; Natsuko TANABE; Narihiro MITSUI; Naoto SUZUKI; Osamu TAKEICHI; Tomoko KATONO; Akira MOROZUMI; Masao MAENO

    2007-01-01

    Previous studies have indicated that lipopolysaccharide (LPS) from Gram-negative bacteria in plaque induces the release of prostaglandin E2 (PGE2),which promotes alveolar bone resorption in periodontitis,and that tobacco smoking might be an important risk factor for the development and severity of periodontitis.We determined the effect of nicotine and LPS on alkaline phosphatase (ALPase)activity,PGE2 production,and the expression of cyclooxygenase (COX-1,COX-2),PGE2 receptors Ep1-4,and macrophage colony stimulating factor(M-CSF)in human osteoblastic Saos-2 cells.The cells were cultured with 10-3 M nicotine in the presence of 0,1,or 10 μg/ml LPS,or with LPS alone.ALPase activity decreased in cells cultured with nicotine or LPS alone,and decreased further in those cultured with both nicotine and LPS,whereas PGE2 production significantly increased in the former and increased further in the latter.By itself,nicotine did not affect expression of COX-1,COX-2,any of the PGE2 receptors,or M-CSF,but when both nicotine and LPS were present,expression of COX-2,Ep3,Ep4,and M-CSF increased significantly.Simultaneous addition of 10-4 M indomethacin eliminated the effects of nicotine and LPS on ALPase activity,PGE2 production,and MCSF expression.Phosphorylation of protein kinase A was high in cells cultured with nicotine and LPS.These results suggest that LPS enhances the production of nicotine-induced PGE2 by an increase in COX-2 expression in osteoblasts,that nicotine-LPS-induced PGE2 interacts with the osteoblast Ep4 receptor primarily in autocrine or paracrine mode,and that the nicotine-LPS-induced PGE2 then decreases ALPase activity and increases M-CSF expression.

  20. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    Directory of Open Access Journals (Sweden)

    A. Zago

    2012-01-01

    Full Text Available Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although cross-sensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P 28-37 and adult (P60-67 rats received nicotine (0.4 mg/kg, sc or saline (0.9% NaCl, sc and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

  1. Protective Effect of White-fleshed Peach (Prunus persica (L.) Batsch) on Chronic Nicotine-induced Toxicity

    Science.gov (United States)

    Kim, Hyun-Jeong; Park, Kwang-Kyun; Chung, Won-Yoon; Lee, Sun Kyoung; Kim, Ki-Rim

    2017-01-01

    Background Nicotine is a major toxic component of tobacco smoke and has been recognized as a risk factor to induce oxidative tissue damage, which is a precursor to cardiovascular diseases, lung-related diseases, and cancers. Peaches (Prunus persica) have been used for the treatment of degenerative disorders, such as hypermenorrhea, dysmenorrhea, and infertility in Asian countries. In this study, we investigated the effects of white-fleshed peach on the excretion of nicotine metabolites and 1-hydroxypyrene in smokers and chronic nicotine-induced tissue damages in mice. Methods The concentrations of cotinine and 1-hydroxypyrene were measured in urine of smokers before or after intake of white-fleshed peaches. In addition, ICR mice were injected with nicotine (5 mg/kg body weight) and then orally administered with white-fleshed peach extracts (WFPE) (250 or 500 mg/kg body weight) for 36 days. The oxidative stress parameters and the activities of antioxidant enzymes were measured in liver and kidney tissues. Also, histological changes and nitrotyrosine expression were assessed. Results Intake of white-fleshed peaches increased the urinary concentration of nicotine metabolites and 1-hydroxypyrene in 91.67% and 83.33% of smokers, respectively. WFPE decreased the malondialdehyde levels and recovered the activities of antioxidant enzymes in nicotine-injected mice. In addition, WFPE inhibited nitrotyrosine expression and inflammatory responses in the liver, kidney, and lung tissues of nicotine-treated mice. Conclusions White-fleshed peaches may increase the metabolism of toxic components in tobacco smoke in smokers and protect normal tissues against nicotine toxicity in mice. Therefore, supplementation of white-fleshed peaches might be beneficial to smokers.

  2. Nicotine-induced survival signaling in lung cancer cells is dependent on their p53 status while its down-regulation by curcumin is independent

    Directory of Open Access Journals (Sweden)

    Puliyappadamba Vineshkumar T

    2010-08-01

    Full Text Available Abstract Background Lung cancer is the most lethal cancer and almost 90% of lung cancer is due to cigarette smoking. Even though nicotine, one of the major ingredients of cigarette smoke and the causative agent for addiction, is not a carcinogen by itself, several investigators have shown that nicotine can induce cell proliferation and angiogenesis. We observed that the proliferative index of nicotine is different in the lung cancer cell lines H1299 (p53-/- and A549 (p53+/+ which indicates that the mode of up-regulation of survival signals by nicotine might be different in cells with and without p53. Results While low concentrations of nicotine induced activation of NF-κB, Akt, Bcl2, MAPKs, AP1 and IAPs in H1299, it failed to induce NF-κB in A549, and compared to H1299, almost 100 times higher concentration of nicotine was required to induce all other survival signals in A549. Transfection of WT-p53 and DN-p53 in H1299 and A549 respectively, reversed the mode of activation of survival signals. Curcumin down-regulated all the survival signals induced by nicotine in both the cells, irrespective of their p53 status. The hypothesis was confirmed when lower concentrations of nicotine induced NF-κB in two more lung cancer cells, Hop-92 and NCI-H522 with mutant p53 status. Silencing of p53 in A549 using siRNA made the cells susceptible to nicotine-induced NF-κB nuclear translocation as in A549 DN-p53 cells. Conclusions The present study reveals a detrimental role of nicotine especially in lung cancer patients with impaired p53 status and identifies curcumin as a potential chemopreventive.

  3. Behavioral modulation of neuronal calcium/calmodulin-dependent protein kinase II activity: differential effects on nicotine-induced spinal and supraspinal antinociception in mice.

    Science.gov (United States)

    Damaj, M Imad

    2007-10-15

    Recent studies have implicated the involvement of Ca(2+)-dependent mechanisms, in particular calcium/calmodulin-dependent protein kinase II (CaM kinase II) in nicotine-induced antinociception using the tail-flick test. The spinal cord was suggested as a possible site of this involvement. The present study was undertaken to investigate the hypothesis that similar mechanisms exist for nicotine-induced antinociception in the hot-plate test, a response thought to be centrally mediated. In order to assess these mechanisms, i.c.v. administered CaM kinase II inhibitors were evaluated for their effects on antinociception produced by either i.c.v. or s.c. administration of nicotine in both tests. In addition, nicotine's analgesic effects were tested in mice lacking half of their CaM kinase II (CaM kinase II heterozygous) and compare it to their wild-type counterparts. Our results showed that although structurally unrelated CaM kinase II inhibitors blocked nicotine's effects in the tail-flick test in a dose-related manner, they failed to block the hot-plate responses. In addition, the antinociceptive effects of systemic nicotine in the tail-flick but not the hot-plate test were significantly reduced in CaM kinase II heterozygous mice. These observations indicate that in contrast to the tail-flick response, the mechanism of nicotine-induced antinociception in the hot-plate test is not mediated primarily via CaM kinase II-dependent mechanisms at the supraspinal level.

  4. Protein kinase Ciota promotes nicotine-induced migration and invasion of cancer cells via phosphorylation of micro- and m-calpains.

    Science.gov (United States)

    Xu, Lijun; Deng, Xingming

    2006-02-17

    Nicotine is a major component in cigarette smoke that activates the growth-promoting pathways to facilitate the development of lung cancer. However, it is not clear whether nicotine affects cell motility to facilitate tumor metastasis. Here we discovered that nicotine potently induces phosphorylation of both mu- and m-calpains via activation of protein kinase Ciota (PKCiota), which is associated with accelerated migration and invasion of human lung cancer cells. Purified PKCiota directly phosphorylates mu- and m-calpains in vitro. Overexpression of PKCiota results in increased phosphorylation of both mu- and m-calpains in vivo. Nicotine also induces activation of c-Src, which is a known PKCiota upstream kinase. Treatment of cells with the alpha(7) nicotinic acetylcholine receptor inhibitor alpha-bungarotoxin can block nicotine-induced calpain phosphorylation with suppression of calpain activity, wound healing, cell migration, and invasion, indicating that nicotine-induced calpain phosphorylation occurs, at least in part, through a signaling pathway involving the upstream alpha(7) nicotinic acetylcholine receptor. Intriguingly, depletion of PKCiota by RNA interference suppresses nicotine-induced calpain phosphorylation, calpain activity, cell migration, and invasion, indicating that PKCiota is a necessary component in nicotine-mediated cell motility signaling. Importantly, nicotine potently induces secretion of mu- and m-calpains from lung cancer cells into culture medium, which may have potential to cleave substrates in the extracellular matrix. These findings reveal a novel role for PKCiota as a nicotine-activated, physiological calpain kinase that directly phosphorylates and activates calpains, leading to enhanced migration and invasion of human lung cancer cells.

  5. Nicotine induced CpG methylation of Pax6 binding motif in StAR promoter reduces the gene expression and cortisol production

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tingting [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Chen, Man; Liu, Lian [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Cheng, Huaiyan [Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Yan, You-E [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Feng, Ying-Hong, E-mail: yhfeng@usuhs.edu [Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Wang, Hui, E-mail: wanghui19@whu.edu.cn [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China)

    2011-12-15

    Steroidogenic acute regulatory protein (StAR) mediates the rate-limiting step in the synthesis of steroid hormones, essential to fetal development. We have reported that the StAR expression in fetal adrenal is inhibited in a rat model of nicotine-induced intrauterine growth retardation (IUGR). Here using primary human fetal adrenal cortex (pHFAC) cells and a human fetal adrenal cell line NCI-H295A, we show that nicotine inhibits StAR expression and cortisol production in a dose- and time-dependent manner, and prolongs the inhibitory effect on cells proliferating over 5 passages after termination of nicotine treatment. Methylation detection within the StAR promoter region uncovers a single site CpG methylation at nt -377 that is sensitive to nicotine treatment. Nicotine-induced alterations in frequency of this point methylation correlates well with the levels of StAR expression, suggesting an important role of the single site in regulating StAR expression. Further studies using bioinformatics analysis and siRNA approach reveal that the single CpG site is part of the Pax6 binding motif (CGCCTGA) in the StAR promoter. The luciferase activity assays validate that Pax6 increases StAR gene expression by binding to the glucagon G3-like motif (CGCCTGA) and methylation of this site blocks Pax6 binding and thus suppresses StAR expression. These data identify a nicotine-sensitive CpG site at the Pax6 binding motif in the StAR promoter that may play a central role in regulating StAR expression. The results suggest an epigenetic mechanism that may explain how nicotine contributes to onset of adult diseases or disorders such as metabolic syndrome via fetal programming. -- Highlights: Black-Right-Pointing-Pointer Nicotine-induced StAR inhibition in two human adrenal cell models. Black-Right-Pointing-Pointer Nicotine-induced single CpG site methylation in StAR promoter. Black-Right-Pointing-Pointer Persistent StAR inhibition and single CpG methylation after nicotine termination

  6. Magnetic Fluid-Based Squeeze Film Behaviour in Curved Porous-Rotating Rough Annular Plates and Elastic Deformation Effect

    Directory of Open Access Journals (Sweden)

    M. E. Shimpi

    2012-01-01

    Full Text Available Efforts have been directed to study and analyze the squeeze film performance between rotating transversely rough curved porous annular plates in the presence of a magnetic fluid lubricant considering the effect of elastic deformation. A stochastic random variable with nonzero mean, variance, and skewness characterizes the random roughness of the bearing surfaces. With the aid of suitable boundary conditions, the associated stochastically averaged Reynolds' equation is solved to obtain the pressure distribution in turn, which results in the calculation of the load-carrying capacity. The graphical representations establish that the transverse roughness, in general, adversely affects the performance characteristics. However, the magnetization registers a relatively improved performance. It is found that the deformation causes reduced load-carrying capacity which gets further decreased by the porosity. This investigation tends to indicate that the adverse effect of porosity, standard deviation and deformation can be compensated to certain extent by the positive effect of the magnetic fluid lubricant in the case of negatively skewed roughness by choosing the rotational inertia and the aspect ratio, especially for suitable ratio of curvature parameters.

  7. Contribution of α4β2 nAChR in nicotine-induced intracellular calcium response and excitability of MSDB neurons.

    Science.gov (United States)

    Wang, Jiangang; Wang, Yali; Wang, Yang; Wang, Ran; Zhang, Yunpeng; Zhang, Qian; Lu, Chengbiao

    2014-12-10

    The neurons of medial septal diagonal band of broca (MSDB) project to hippocampus and play an important role in MSDB-hippocampal synaptic transmission, plasticity and network oscillation. Nicotinic acetylcholine receptor (nAChR) subunits, α4β2 and α7 nAChRs, are expressed in MSDB neurons and permeable to calcium ions, which may modulate the function of MSDB neurons. The aims of this study are to determine the roles of selective nAChR activation on the calcium responses and membrane currents in MSDB neurons. Our results showed that nicotine increased calcium responses in the majority of MSDB neurons, pre-treatment of MSDB slices with a α4β2 nAChR antagonist, DhβE but not a α7 nAChR antagonist, MLA prevented nicotine-induced calcium responses. The whole cell patch clamp recordings showed that nicotine-induced inward current and acetylcholine (ACh) induced-firing activity can be largely reduced or prevented by DhβE in MSDB neurons. Surprisingly, post-treatment of α4β2 or α7 nAChR antagonists failed to block nicotine׳s role, they increased calcium responses instead. Application of calcium chelator EGTA reduced calcium responses in all neurons tested. These results suggest that there was a subtype specific modulation of nAChRs on calcium signaling and membrane currents in MSDB neurons and nAChR antagonists were also able to induce calcium responses involving a distinct mechanism.

  8. The glucagon-like peptide 1 analogue Exendin-4 attenuates the nicotine-induced locomotor stimulation, accumbal dopamine release, conditioned place preference as well as the expression of locomotor sensitization in mice.

    Directory of Open Access Journals (Sweden)

    Emil Egecioglu

    Full Text Available The gastrointestinal peptide glucagon-like peptide 1 (GLP-1 is known to regulate consummatory behavior and is released in response to nutrient ingestion. Analogues of this peptide recently emerged as novel pharmacotherapies for treatment of type II diabetes since they reduce gastric emptying, glucagon secretion as well as enhance glucose-dependent insulin secretion. The findings that GLP-1 targets reward related areas including mesolimbic dopamine areas indicate that the physiological role of GLP-1 extends beyond food intake and glucose homeostasis control to include reward regulation. The present series of experiments was therefore designed to investigate the effects of the GLP-1 receptor agonist, Exendin-4 (Ex4, on established nicotine-induced effects on the mesolimbic dopamine system in mice. Specifically, we show that treatment with Ex4, at a dose with no effect per se, attenuate nicotine-induced locomotor stimulation, accumbal dopamine release as well as the expression of conditioned place preference in mice. In accordance, Ex4 also blocks nicotine-induced expression of locomotor sensitization in mice. Given that development of nicotine addiction largely depends on the effects of nicotine on the mesolimbic dopamine system these findings indicate that the GLP-1 receptor may be a potential target for the development of novel treatment strategies for nicotine cessations in humans.

  9. Effect of calcium on nicotine-induced current expressed by an atypical alpha-bungarotoxin-insensitive nAChR2.

    Science.gov (United States)

    Thany, Steeve H; Courjaret, Raphael; Lapied, Bruno

    2008-06-27

    Two distinct native alpha-bungarotoxin (alpha-Bgt)-insensitive nicotinic acetylcholine receptors (nAChRs), named nAChR1 and nAChR2, were identified in the cockroach Periplaneta americana dorsal unpaired median (DUM) neurons. They differed in their electrophysiological, pharmacological properties and intracellular regulation pathways. nAChR2 being an atypical nicotinic receptor closed upon agonist application and its current-voltage relationship resulted from a reduction in potassium conductance. In this study, using whole-cell patch-clamp technique, we demonstrated that calcium modulated nAChR2-mediated nicotine response. Under 0.5 microM alpha-Bgt and 20 mM d-tubocurarine, the nicotine-induced inward current amplitude was strongly reduced in the presence of intracellularly applied BAPTA or bath application of calcium-free solution. In addition, using cadmium chloride, we showed that nicotine response was modulated by extracellular calcium through plasma membrane calcium channels. Moreover, extracellular application of caffeine and thapsigargin reduced nAChR2-mediated response. Together these experiments revealed a complex calcium-dependent regulation of nAChR2.

  10. NeuroD1 mediates nicotine-induced migration and invasion via regulation of the nicotinic acetylcholine receptor subunits in a subset of neural and neuroendocrine carcinomas.

    Science.gov (United States)

    Osborne, Jihan K; Guerra, Marcy L; Gonzales, Joshua X; McMillan, Elizabeth A; Minna, John D; Cobb, Melanie H

    2014-06-01

    Cigarette smoking is a major risk factor for acquisition of small cell lung cancer (SCLC). A role has been demonstrated for the basic helix-loop-helix transcription factor NeuroD1 in the pathogenesis of neural and neuroendocrine lung cancer, including SCLC. In the present study we investigate the possible function of NeuroD1 in established tumors, as well as actions early on in pathogenesis, in response to nicotine. We demonstrate that nicotine up-regulates NeuroD1 in immortalized normal bronchial epithelial cells and a subset of undifferentiated carcinomas. Increased expression of NeuroD1 subsequently leads to regulation of expression and function of the nicotinic acetylcholine receptor subunit cluster of α3, α5, and β4. In addition, we find that coordinated expression of these subunits by NeuroD1 leads to enhanced nicotine-induced migration and invasion, likely through changes in intracellular calcium. These findings suggest that aspects of the pathogenesis of neural and neuroendocrine lung cancers may be affected by a nicotine- and NeuroD1-induced positive feedback loop.

  11. Influence of rotational speed of centrifugal casting process on appearance, microstructure, and sliding wear behaviour of Al-2Si cast alloy

    Science.gov (United States)

    Mukunda, P. G.; Shailesh, Rao A.; Rao, Shrikantha S.

    2010-02-01

    Although the manner in which the molten metal flows plays a major role in the formation of the uniform cylinder in centrifugal casting, not much information is available on this topic. The flow in the molten metal differs at various rotational speeds, which in turn affects the final casting. In this paper, the influence of the flow of molten metal of hyper eutectic Al-2Si alloys at various rotational speeds is discussed. At an optimum speed of 800 rpm, a uniform cylinder was formed. For the rotational speeds below and above these speeds, an irregular shaped casting was formed, which is mainly due to the influence of melt. Primary á-Al particles were formed in the tube periphery at low rotational speed, and their sizes and shapes were altered with changes in rotational speeds. The wear test for the inner surface of the casting showed better wear properties for the casting prepared at the optimum speed of rotation.

  12. Ameliorating effect of vitamin C and selenium against nicotine induced oxidative stress and changes of p53 expression in pregnant albino rats

    Directory of Open Access Journals (Sweden)

    Khadiga A. Hassan

    2016-12-01

    Full Text Available Objective: This study was aimed to evaluate the effects of daily intake of vitamin C or selenium against deleterious effects of nicotine toxicity on pregnant albino rats. Materials and methods: Forty albino pregnant rats were equally distributed into four groups. Group A was considered as control. Group B was administered with nicotine dosed at 1 mg/kg body weight (bwt daily for 7 weeks (wks from 1st day of gestation until the postnatal 4 wks. Group C was treated with nicotine and vitamin C dosed at 1 mg/kg bwt orally for 7 wks, group D was treated with nicotine and sodium selenite dosed at 1 ug/100 g bwt concurrently for 7 wks. The levels of catalase (CAT, superoxide dismutase (SOD, protein carbonyl (PC and thiobarbituric acid reactive substances (TBARS, were estimated in homogenates of the lung, kidney and liver. Histopathological studies using hematoxylin and eosin as well as immunohistochemical studies using p53 antibody were also done. Results: Nicotine significantly elevated the levels of TBARS and PC as compared to control rats. Groups C and D showed decrease in these levels significantly. CAT and SOD activities of group B were decreased significantly. Significant elevation of CAT and SOD activities was detected in both groups C and D. Vitamin C elevated the antioxidant enzymes activities to normal levels, however selenium administration improved these levels but still lower than those of group A. Expression of p53 was decreased in group B as compared to group A. Vitamin C completely reversed the expression of p53 as group A. However, group D did not showed any significant changes in expressions as compared to group B. Conclusion: It is concluded that vitamin C intake was useful than selenium in prevention against nicotine-induced oxidative stress including p53 expression in the lung, kidney and liver of pregnant rats. [J Adv Vet Anim Res 2016; 3(4.000: 321-331

  13. Nicotine-induced enhancement of synaptic plasticity at CA3-CA1 synapses requires GABAergic interneurons in adult anti-NGF mice.

    Science.gov (United States)

    Rosato-Siri, Marcelo; Cattaneo, Antonino; Cherubini, Enrico

    2006-10-15

    GABAergic interneurons. Together, these experiments indicate that in AD 11 mice a rearrangement of the GABAergic circuit can 'rescue' nicotine-induced potentiation of synaptic plasticity. This may be relevant for developing proper therapeutic tools useful for the treatment of AD.

  14. Reversal effect of sulpiride on rotational behaviour of rats with unilateral frontal cortex ablation: an alternative explanation for the pharmacological mechanism of its antidepressant effect.

    Science.gov (United States)

    Kaneno, S; Fukamauchi, F; Komatsu, H; Koyama, K; Ikawa, K

    2001-02-01

    The antidepressant effect of sulpiride has been generally explained as the result of its preferential blocking effect on self-inhibitory presynaptic dopamine autoreceptors at low doses. Low dose haloperidol has the same blocking effect. In rats with unilateral ablation of the frontal cortex, methamphetamine administration induced mild contralateral rotation 10 days after the operation. We examined whether low dose sulpiride and haloperidol would have the same effect on this rotational model. High dose sulpiride (100 mg/kg) or low dose haloperidol (0.05 mg/kg) prevented this methamphetamine-induced rotation. However, low dose (15 mg/kg) sulpiride clearly reversed the direction of rotation. This reversal effect of low dose sulpiride is not explained by the preferential blocking effect on dopamine autoreceptors. The results suggest that low dose sulpiride, unlike low dose haloperidol, has a prominent blocking effect on D2 receptors in the frontal cortex. This unique effect of sulpiride may be relevant to its clinical antidepressant and anxiolytic effects at low doses.

  15. Design of a medical non-linear drilling device: the influence of twist and wear on the fatigue behaviour of NiTi wires subjected to bending rotation

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, M.; Frenzel, J.; Eggeler, G. [Lehrstuhl Werkstoffwissenschaften, Ruhr-Universitaet Bochum, 44780 Bochum (Germany); Richter, J.; Groenemeyer, D. [Institut fuer Mikrotherapie, Universitaet Witten/ Herdecke (Germany)

    2004-05-01

    This paper considers fundamental and experimental aspects associated with the engineering design of a medical, non-linear drilling device which exploits shape memory pseudoelasticity of NiTi wires. For this application it is important that the NiTi wires have a good fatigue resistance. This is why the present authors have previously determined the influence of various parameters on cyclic life, crack growth and stress state of pseudoelastic wires subjected to bending rotation fatigue. The actual drilling device has to withstand twist in addition to bending rotation because the free rotation is constrained by friction between the drill head and the bone material. In addition, friction between the wire and a NiTi guiding tube results in wear and this may well promote fatigue crack nucleation. In this paper, we explain the function of the medical drill. We then report results on the effect of the additional parameters (1) twist and (2) wear on the fatigue life of thin pseudoelastic NiTi wires. We finally discuss the implications of our experimental results for the design process of the medical drilling device. (Abstract Copyright [2004], Wiley Periodicals, Inc.) [German] Dieser Artikel behandelt Voruntersuchungen fuer die Entwicklung eines medizinischen nicht-linearen Bohrsystems. Aus materialwissenschaftlicher Sicht spielt die Ermuedung der mechanischen Komponenten aus NiTi eine wichtige Rolle. Die Autoren haben in bisherigen Studien den Einfluss verschiedener Parameter auf Lebensdauer, Risswachstum und Spannungszustand in pseudoelastischen Draehten waehrend Umlaufbiegung ermittelt. Der Draht im eigentlichen Bohrsystem wird jedoch nicht ausschliesslich durch reine Umlaufbiegung, sondern zusaetzlich durch eine Verdrillung aufgrund der Reibung zwischen Bohrkopf und Knochengewebe, belastet. Ausserdem bewirkt die Reibung zwischen dem Draht und einem Fuehrungsrohr aus NiTi Verschleiss; diese Materialschaedigung stellt einen weiteren Mechanismus zur Risseinleitung dar. In

  16. Model dependence of the multi-transonic behaviour, stability properties and the corresponding acoustic geometry for accretion onto rotating black holes

    Science.gov (United States)

    Saha, Sonali; Sen, Sharmistha; Nag, Sankhasubhra; Raychowdhury, Suparna; Das, Tapas K.

    2016-02-01

    Stationary, multi-transonic, integral solutions of hydrodynamic axisymmetric accretion onto a rotating black hole have been compared for different geometrical configurations of the associated accretion disc structures described using the polytropic as well as the isothermal equations of state. Such analysis is performed for accretion under the influence of generalised post Newtonian pseudo Kerr black hole potential. The variations of the stationary shock characteristics with black hole spin have been studied in details for all the disc models and are compared for the flow characterised by the two aforementioned equations of state. Using a novel linear perturbation technique it has been demonstrated that the aforementioned stationary solutions are stable, at least upto an astrophysically relevant time scale. It has been demonstrated that the emergence of the horizon related gravity like phenomena (the analogue gravity effects) is a natural consequence of such stability analysis, and the corresponding acoustic geometry embedded within the transonic accretion can be constructed for the propagation of the linear acoustic perturbation of the mass accretion rate. The analytical expression for the associated sonic surface gravity κ has been obtained self consistently. The variations of κ with the black hole spin parameter for all different geometric configurations of matter and for various thermodynamic equations of state have been demonstrated.

  17. Rotating flow

    CERN Document Server

    Childs, Peter R N

    2010-01-01

    Rotating flow is critically important across a wide range of scientific, engineering and product applications, providing design and modeling capability for diverse products such as jet engines, pumps and vacuum cleaners, as well as geophysical flows. Developed over the course of 20 years' research into rotating fluids and associated heat transfer at the University of Sussex Thermo-Fluid Mechanics Research Centre (TFMRC), Rotating Flow is an indispensable reference and resource for all those working within the gas turbine and rotating machinery industries. Traditional fluid and flow dynamics

  18. Rotating Wavepackets

    Science.gov (United States)

    Lekner, John

    2008-01-01

    Any free-particle wavepacket solution of Schrodinger's equation can be converted by differentiations to wavepackets rotating about the original direction of motion. The angular momentum component along the motion associated with this rotation is an integral multiple of [h-bar]. It is an "intrinsic" angular momentum: independent of origin and…

  19. Rotational superradiance in fluid laboratories

    CERN Document Server

    Cardoso, Vitor; Richartz, Mauricio; Weinfurtner, Silke

    2016-01-01

    Rotational superradiance has been predicted theoretically decades ago, and is the chief responsible for a number of important effects and phenomenology in black hole physics. However, rotational superradiance has never been observed experimentally. Here, with the aim of probing superradiance in the lab, we investigate the behaviour of sound and surface waves in fluids resting in a circular basin at the center of which a rotating cylinder is placed. We show that with a suitable choice for the material of the cylinder, surface and sound waves are amplified. By confining the superradiant modes near the rotating cylinder, an instability sets in. Our findings are experimentally testable in existing fluid laboratories and hence offer experimental exploration and comparison of dynamical instabilities arising from rapidly rotating boundary layers in astrophysical as well as in fluid dynamical systems.

  20. Rotational elasticity

    Science.gov (United States)

    Vassiliev, Dmitri

    2017-04-01

    We consider an infinite three-dimensional elastic continuum whose material points experience no displacements, only rotations. This framework is a special case of the Cosserat theory of elasticity. Rotations of material points are described mathematically by attaching to each geometric point an orthonormal basis that gives a field of orthonormal bases called the coframe. As the dynamical variables (unknowns) of our theory, we choose the coframe and a density. We write down the general dynamic variational functional for our rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when dealing with rotations because rotations in dimension three are inherently nonlinear (rotations about different axes do not commute) and because there is no reason to exclude from our study large rotations such as full turns. The main result of the talk is an explicit construction of a class of time-dependent solutions that we call plane wave solutions; these are travelling waves of rotations. The existence of such explicit closed-form solutions is a non-trivial fact given that our system of Euler-Lagrange equations is highly nonlinear. We also consider a special case of our rotational theory of elasticity which in the stationary setting (harmonic time dependence and arbitrary dependence on spatial coordinates) turns out to be equivalent to a pair of massless Dirac equations. The talk is based on the paper [1]. [1] C.G.Boehmer, R.J.Downes and D.Vassiliev, Rotational elasticity, Quarterly Journal of Mechanics and Applied Mathematics, 2011, vol. 64, p. 415-439. The paper is a heavily revised version of preprint https://arxiv.org/abs/1008.3833

  1. Rotation curve of the Milky Way

    Directory of Open Access Journals (Sweden)

    Lee Y.S.

    2012-02-01

    Full Text Available We use SEGUE and Hipparcos data to restrict the behaviour of the rotation curve of the Milky Way in the solar neighbourhood. Then we construct a density model of the Milky Way which best reproduces the available observations of the rotation curve and is consistent with the density constraints in the solar neighbourhood.

  2. Pattern formation in rotating fluids

    Science.gov (United States)

    Bühler, Karl

    2009-06-01

    Flows in nature and technology are often associated with specific structures and pattern. This paper deals with the development and behaviour of such flow pattern. Flow structures are important for the mass, momentum and energy transport. The behaviour of different flow pattern is used by engineers to obtain an efficient mass and energy consumption. Mechanical power is transmitted via the momentum of rotating machine parts. Therefore the physical and mathematical knowledge of these basic concepts is important. Theoretical and experimental investigations of principle experiments are described in the following. We start with the classical problem of the flow between two concentric cylinders where the inner cylinder rotates. Periodic instabilities occur which are called Taylor vortices. The analogy between the cylindrical gap flow, the heat transfer in a horizontal fluid layer exposed to the gravity field and the boundary layer flow along concave boundaries concerning their stability behaviour is addressed. The vortex breakdown phenomenon in a cylinder with rotating cover is also described. A generalization to spherical sectors leads then to investigations with different boundary conditions. The spherical gap flow exhibits interesting phenomena concerning the nonlinear character of the Navier-Stokes equations. Multiple solutions in the nonlinear regime give rise to different routes during the laminar-turbulent transition. The interaction of two rotating spheres results in flow structures with separation and stagnation lines. Experimental results are confirmed by numerical simulations.

  3. Hydrodynamic Instabilities in Rotating Fluids

    Institute of Scientific and Technical Information of China (English)

    KarlBuehler

    2000-01-01

    Rotating flow systems are often used to study stability phenomena and structure developments.The closed spherical gap prblem is generalized into an open flow system by superimposing a mass flux in meridional direction.The basic solutions at low Reynolds numbers are described by analytical methods.The nonlinear supercritical solutions are simulated numerically and realized in experiments.Novel steady and time-dependent modes of flows are obtained.The extensive results concern the stability behaviour.non-uniqueness of supercritical solutions,symmetry behaviour and transitions between steady and time-dependent solutions.The experimental investigations concern the visualization of the various instabilities and the quatitative description of the flow structures including the laminar-turbulent transition.A Comparison between theoretical and experimental results shows good agreement within the limit of rotational symmetric solutions from the theory.

  4. Boundary layer control of rotating convection systems.

    Science.gov (United States)

    King, Eric M; Stellmach, Stephan; Noir, Jerome; Hansen, Ulrich; Aurnou, Jonathan M

    2009-01-15

    Turbulent rotating convection controls many observed features of stars and planets, such as magnetic fields, atmospheric jets and emitted heat flux patterns. It has long been argued that the influence of rotation on turbulent convection dynamics is governed by the ratio of the relevant global-scale forces: the Coriolis force and the buoyancy force. Here, however, we present results from laboratory and numerical experiments which exhibit transitions between rotationally dominated and non-rotating behaviour that are not determined by this global force balance. Instead, the transition is controlled by the relative thicknesses of the thermal (non-rotating) and Ekman (rotating) boundary layers. We formulate a predictive description of the transition between the two regimes on the basis of the competition between these two boundary layers. This transition scaling theory unifies the disparate results of an extensive array of previous experiments, and is broadly applicable to natural convection systems.

  5. Pyrilamine inhibits nicotine-induced catecholamine secretion.

    Science.gov (United States)

    Kim, Dong-Chan; Yun, So Jeong; Park, Yong-Soo; Jun, Dong-Jae; Kim, Dongjin; Jiten Singh, N; Kim, Sanguk; Kim, Kyong-Tai

    2014-07-01

    Function of nicotine, which induces activation of all parts of the body including our brain, has been receiving much attention for a long period of time and also been actively studied by researchers for its pharmacological actions in the central nervous system. The modulation of nicotine concentration and the inhibition of nicotine binding on target receptors in the brain are the key factors for smoking addiction therapy. In previous studies showed that influx of nicotine at the blood-brain barrier was through the pyrilamine-sensitive organic cation transporters. But the direct interacting mechanism of pyrilamine on the nicotine binding target receptors has not yet been clarified. The aim of the present study is to investigate the direct binding mechanisms of a pyrilamine on the nicotinic acetylcholine receptors (nAChRs). We found that pyrilamine shares the same ligand binding pocket of nicotine (NCT) on nAChRs but interacts with more amino acid residues than NCT does. The extended part of pyrilamine interacts with additional residues in the ligand binding pocket of nAChRs which are located nearby the entrance of the binding pocket. The catecholamine (CA) secretion induced by nAChR agonist (NCT') was significantly inhibited by the pyrilamine pretreatment. Real time carbon-fiber amperometry confirmed the inhibition of the NCT'-induced exocytosis by pyrilamine in a single cell level. We also found that pyrilamine inhibited the NCT'-induced [Ca(2+)]i. In contrast, pyrilamine did not affect the increase in calcium induced by high K(+). Overall, these data suggest that pyrilamine directly docks into the ligand binding site of nAChRs and specifically inhibits the nAChR-mediated effects thereby causing inhibition of CA secretion. Therefore, pyrilamine may play an important role to explore new treatments to aid smoking cessation.

  6. Suicidal behaviour

    NARCIS (Netherlands)

    Neeleman, J

    2001-01-01

    -Prevention of suicidal behaviour remains difficult, despite increasing knowledge of its determinants. Health service efforts hardly affect suicide rates. -Recent shifts in the epidemiology of suicidal behaviour are rising rates among the young and increasing use of violent methods. these can be lin

  7. Chaotic scattering off a rotating target

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, N.; Benet, L.; Lipp, C.; Trautmann, D.; Jung, C.; Seligman, T.H. [Inst. fuer Theor. Phys., Basel Univ. (Switzerland)

    1995-05-07

    We study the classical scattering of a point particle from one and two rotating hard discs in a plane, as an idealization of the scattering off a rotating target. The system displays regular or chaotic behaviour depending on the value of the only constant of motion: the Jacobi integral. We present results on the transition between regular and chaotic behaviour in terms of the periodic orbits of the system. For certain ranges of the Jacobi integral the dynamics is fully hyperbolic. The number of symbols needed to characterize the invariant set is different in each of those intervals and may become arbitrarily high. (author)

  8. Acoustic Rotation Modes in Complex Plasmas

    Institute of Scientific and Technical Information of China (English)

    白冬雪; 王正汹; 王晓钢

    2004-01-01

    Acoustic rotation modes in complex plasmas are investigated in a cylindrical system with an axial symmetry.The linear mode solution is derived. The mode in an infinite area is reduced to a classical dust acoustic wave in the region away from the centre. When the dusty plasma is confined in a finite region, the breathing and rotating-void behaviour are observed. Vivid structures of different mode number solutions are illustrated.

  9. Behavioural Modernity

    OpenAIRE

    McLean, Laura

    2015-01-01

    Behavioural Modernity explores the changing politics of representation and ethics of care in curatorial practice, necessitated by an increasing blurring of boundaries between the human, the technological, and the planetary.

  10. Sickness Behaviour:

    African Journals Online (AJOL)

    adaptive function for hyperthermia and ... on immunity. However ... infectious disorders probably lies in the ... nervous system, and thus behaviour, .... Fever: Basic ... system. In Ader R, Felten DL,. Cohen N, editors. Psychoneuro- immunology.

  11. Behavioural lateralisation in reindeer

    Directory of Open Access Journals (Sweden)

    Yngve Espmark

    2002-06-01

    Full Text Available Reindeer (Rangifer tarandus kept in corrals or otherwise forced to clump typically start milling in response to stressing events. This behaviour is generally considered to have an antipredator effect. An inquiry on herd behaviour, to which 35 Norwegian reindeer husbandry districts responded, showed that 32 experienced that corralled rein¬deer consistently circled leftwards, whereas the remaining three reported consistently rightward circling. Regular monitoring of a reindeer herd in central Norway over a two-year period (1993-94, and experimental studies on a fraction of the same herd, revealed the following traits. Free-ranging reindeer showed no right- or left-turning preference during grazing or browsing, but when the reindeer were driven into corrals or forced to clump in the open they invariably rotated leftwards. The circling of corralled reindeer was triggered at an average group size of 20 to 25 animals, apparently independently of the age and sex of the animals. When they dug craters in the snow to reach food, the reindeer used their left foreleg significantly more often than their right. In 23 out of 35 reindeer, the right hemisphere of the brain was heavier than the left. However, in the sample as a whole, the weights of the left and right hemispheres did not differ significantly. Lateralised behaviour in reindeer is thought to be determined by natural and stress induced asymmetries in brain structure and hormonal activity. In addition, learning is probably important for passing on the behaviour between herd members and generations. Differences in lateralised behaviour between nearby herds are thought to be related primarily to different exposure to stress and learning, whereas genetical and environmental fac¬tors (e.g. diet, age structure and sex ratio are probably more important for explaining differences between distant pop¬ulations.

  12. Spin down of the core rotation in red giants

    NARCIS (Netherlands)

    Mosser, B.; Goupil, M.J.; Belkacem, K.; Marques, J.P.; Beck, P.G.; Bloemen, S.; De Ridder, J.; Barban, C.; Deheuvels, S.; Elsworth, Y.; Hekker, S.; Kallinger, T.; Ouazzani, R.M.; Pinsonneault, M.; Samadi, R.; Stello, D.; García, R.A.; Klaus, T.C.; Li, J.; Mathur, S.; Morris, R.L.

    2012-01-01

    Context. The space mission Kepler provides us with long and uninterrupted photometric time series of red giants. We are now able to probe the rotational behaviour in their deep interiors using the observations of mixed modes. Aims. We aim to measure the rotational splittings in red giants and to

  13. Rotator cuff exercises

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000357.htm Rotator cuff exercises To use the sharing features on this ... gov/pubmed/25560729 . Read More Frozen shoulder Rotator cuff problems Rotator cuff repair Shoulder arthroscopy Shoulder CT scan Shoulder ...

  14. On the role of nonsynchronous rotating damping in rotordynamics

    OpenAIRE

    Giancarlo Genta; Eugenio Brusa

    2000-01-01

    Nonsynchronous rotating damping, i.e. energy dissipations occurring in elements rotating at a speed different from the spin speed of a rotor, can have substantial effects on the dynamic behaviour and above all on the stability of rotating systems.The free whirling and unbalance response for systems with nonsynchronous damping are studied using Jeffcott rotor model. The system parameters affecting stability are identified and the threshold of instability is computed. A general model for a mult...

  15. Rotating Cavitation Supression Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a rotating cavitation (RC) suppressor for liquid rocket engine turbopump inducers. Cavitation instabilities, such as rotating...

  16. Consumer behaviours

    DEFF Research Database (Denmark)

    Grønhøj, Alice

    2016-01-01

    Energy-saving programmes are increasingly targeted at children to encourage household energy conservation. A study involving the assignment of energy-saving interventions to Girl Scouts shows that a child-focused intervention can improve energy-saving behaviours among children and their parents....

  17. Mesophase behaviour of polyhedral particles

    KAUST Repository

    Agarwal, Umang

    2011-02-13

    Translational and orientational excluded-volume fields encoded in particles with anisotropic shapes can lead to purely entropy-driven assembly of morphologies with specific order and symmetry. To elucidate this complex correlation, we carried out detailed Monte Carlo simulations of six convex space-filling polyhedrons, namely, truncated octahedrons, rhombic dodecahedrons, hexagonal prisms, cubes, gyrobifastigiums and triangular prisms. Simulations predict the formation of various new liquid-crystalline and plastic-crystalline phases at intermediate volume fractions. By correlating these findings with particle anisotropy and rotational symmetry, simple guidelines for predicting phase behaviour of polyhedral particles are proposed: high rotational symmetry is in general conducive to mesophase formation, with low anisotropy favouring plastic-solid behaviour and intermediate anisotropy (or high uniaxial anisotropy) favouring liquid-crystalline behaviour. It is also found that dynamical disorder is crucial in defining mesophase behaviour, and that the apparent kinetic barrier for the liquid-mesophase transition is much lower for liquid crystals (orientational order) than for plastic solids (translational order). © 2011 Macmillan Publishers Limited. All rights reserved.

  18. Static Behaviour of Bucket Foundations

    DEFF Research Database (Denmark)

    Larsen, Kim André

    . The monopod concept is investigated in this thesis, regarding the static behaviour from loads relevant to offshore wind turbines. The main issue in this concept is the rotational stiffness of the foundation and the combined capacity dominated by moments. The vertical bearing capacity of bucket foundations...... theory is proposed. The proposed expression applies to plane strain as well as axis-symmetric stress conditions for foundations with smooth or rough bases. A thorough experimental investigation of the static behaviour of bucket foundations subjected to combined loading is carried out. Laboratory tests...... method is concluded to be a superior method in estimating the post peak behaviour as well as the combined capacity of bucket foundations in relation to the offshore wind turbine problem....

  19. Modelling Behaviour

    DEFF Research Database (Denmark)

    2015-01-01

    This book reflects and expands on the current trend in the building industry to understand, simulate and ultimately design buildings by taking into consideration the interlinked elements and forces that act on them. This approach overcomes the traditional, exclusive focus on building tasks, while....... The chapter authors were invited speakers at the 5th Symposium "Modelling Behaviour", which took place at the CITA in Copenhagen in September 2015....

  20. On the rotational dynamics of Prometheus and Pandora

    CERN Document Server

    Melnikov, A V; 10.1007/s10569-008-9131-z

    2013-01-01

    Possible rotation states of two satellites of Saturn, Prometheus (S16) and Pandora (S17), are studied by means of numerical experiments. The attitude stability of all possible modes of synchronous rotation and the motion close to these modes is analyzed by means of computation of the Lyapunov spectra of the motion. The stability analysis confirms that the rotation of Prometheus and Pandora might be chaotic, though the possibility of regular behaviour is not excluded. For the both satellites, the attitude instability zones form series of concentric belts enclosing the main synchronous resonance center in the phase space sections. A hypothesis is put forward that these belts might form "barriers" for capturing the satellites in synchronous rotation. The satellites in chaotic rotation can mimic ordinary regular synchronous behaviour: they preserve preferred orientation for long periods of time, the largest axis of satellite's figure being directed approximately towards Saturn.

  1. Rotator cuff repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100229.htm Rotator cuff repair - series—Normal anatomy To use the sharing ... to slide 4 out of 4 Overview The rotator cuff is a group of muscles and tendons that ...

  2. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    1999-01-01

    In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...

  3. Rotations with Rodrigues' Vector

    Science.gov (United States)

    Pina, E.

    2011-01-01

    The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears…

  4. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    2001-01-01

    In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...

  5. Modelling Behaviour

    DEFF Research Database (Denmark)

    2015-01-01

    This book reflects and expands on the current trend in the building industry to understand, simulate and ultimately design buildings by taking into consideration the interlinked elements and forces that act on them. This approach overcomes the traditional, exclusive focus on building tasks, while....... The chapter authors were invited speakers at the 5th Symposium "Modelling Behaviour", which took place at the CITA in Copenhagen in September 2015....... posing new challenges in all areas of the industry from material and structural to the urban scale. Contributions from invited experts, papers and case studies provide the reader with a comprehensive overview of the field, as well as perspectives from related disciplines, such as computer science...

  6. RoboPol: optical polarization-plane rotations and flaring activity in blazars

    CERN Document Server

    Blinov, D; Papadakis, I E; Hovatta, T; Pearson, T J; Liodakis, I; Panopoulou, G V; Angelakis, E; Baloković, M; Das, H; Khodade, P; Kiehlmann, S; King, O G; Kus, A; Kylafis, N; Mahabal, A; Marecki, A; Modi, D; Myserlis, I; Paleologou, E; Papamastorakis, I; Pazderska, B; Pazderski, E; Rajarshi, C; Ramaprakash, A; Readhead, A C S; Reig, P; Tassis, K; Zensus, J A

    2016-01-01

    We present measurements of rotations of the optical polarization of blazars during the second year of operation of RoboPol, a monitoring programme of an unbiased sample of gamma-ray bright blazars specially designed for effective detection of such events, and we analyse the large set of rotation events discovered in two years of observation. We investigate patterns of variability in the polarization parameters and total flux density during the rotation events and compare them to the behaviour in a non-rotating state. We have searched for possible correlations between average parameters of the polarization-plane rotations and average parameters of polarization, with the following results: (1) there is no statistical association of the rotations with contemporaneous optical flares; (2) the average fractional polarization during the rotations tends to be lower than that in a non-rotating state; (3) the average fractional polarization during rotations is correlated with the rotation rate of the polarization plane...

  7. An improved turbulence model for rotating shear flows*

    Science.gov (United States)

    Nagano, Yasutaka; Hattori, Hirofumi

    2002-01-01

    In the present study, we construct a turbulence model based on a low-Reynolds-number non-linear k e model for turbulent flows in a rotating channel. Two-equation models, in particular the non-linear k e model, are very effective for solving various flow problems encountered in technological applications. In channel flows with rotation, however, the explicit effects of rotation only appear in the Reynolds stress components. The exact equations for k and e do not have any explicit terms concerned with the rotation effects. Moreover, the Coriolis force vanishes in the momentum equation for a fully developed channel flow with spanwise rotation. Consequently, in order to predict rotating channel flows, after proper revision the Reynolds stress equation model or the non-linear eddy viscosity model should be used. In this study, we improve the non-linear k e model so as to predict rotating channel flows. In the modelling, the wall-limiting behaviour of turbulence is also considered. First, we evaluated the non-linear k e model using the direct numerical simulation (DNS) database for a fully developed rotating turbulent channel flow. Next, we assessed the non-linear k e model at various rotation numbers. Finally, on the basis of these assessments, we reconstruct the non-linear k e model to calculate rotating shear flows, and the proposed model is tested on various rotation number channel flows. The agreement with DNS and experiment data is quite satisfactory.

  8. Algebraic disturbances and their consequences in rotating channel flow transition

    CERN Document Server

    Jose, Sharath; Pier, Benoît; Govindarajan, Rama

    2016-01-01

    It is now established that subcritical mechanisms play a crucial role in the transition to turbulence of non-rotating plane shear flows. The role of these mechanisms in rotating channel flow is examined here in the linear and nonlinear stages. Distinct patterns of behaviour are found: the transient growth leading to nonlinearity at low rotation rates $Ro$, a highly chaotic intermediate $Ro$ regime, a localised weak chaos at higher $Ro$, and complete stabilization of transient disturbances at very high $Ro$. At very low $Ro$, the transient growth amplitudes are close to those for non-rotating flow, but Coriolis forces already assert themselves by producing distinct asymmetry about the channel centreline. Nonlinear processes are then triggered, in a streak-breakdown mode of transition. The high $Ro$ regimes do not show these signatures, here the leading eigenmode emerges as dominant in the early stages. Elongated structures plastered close to one wall are seen at higher rotation rates. Rotation is shown to redu...

  9. Predictors of human rotation.

    Science.gov (United States)

    Stochl, Jan; Croudace, Tim

    2013-01-01

    Why some humans prefer to rotate clockwise rather than anticlockwise is not well understood. This study aims to identify the predictors of the preferred rotation direction in humans. The variables hypothesised to influence rotation preference include handedness, footedness, sex, brain hemisphere lateralisation, and the Coriolis effect (which results from geospatial location on the Earth). An online questionnaire allowed us to analyse data from 1526 respondents in 97 countries. Factor analysis showed that the direction of rotation should be studied separately for local and global movements. Handedness, footedness, and the item hypothesised to measure brain hemisphere lateralisation are predictors of rotation direction for both global and local movements. Sex is a predictor of the direction of global rotation movements but not local ones, and both sexes tend to rotate clockwise. Geospatial location does not predict the preferred direction of rotation. Our study confirms previous findings concerning the influence of handedness, footedness, and sex on human rotation; our study also provides new insight into the underlying structure of human rotation movements and excludes the Coriolis effect as a predictor of rotation.

  10. The spatial rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan; Hahn, Ute; Larsen, Jytte Overgaard

    2013-01-01

    to identify the specific tissue region under study. In order to use the spatial rotator in practice, however, it is necessary to be able to identify intersection points between cell boundaries and test rays in a series of parallel focal planes, also at the peripheral parts of the cell boundaries. In cases......This paper presents a new local volume estimator, the spatial rotator, which is based on measurements on a virtual 3D probe, using computer assisted microscopy. The basic design of the probe builds upon the rotator principle which requires only a few manual intersection markings, thus making...... the spatial rotator fast to use. Since a 3D probe is involved, it is expected that the spatial rotator will be more efficient than the the nucleator and the planar rotator, which are based on measurements in a single plane. An extensive simulation study shows that the spatial rotator may be more efficient...

  11. Static Behaviour of Bucket Foundations

    DEFF Research Database (Denmark)

    Larsen, Kim André

    . The monopod concept is investigated in this thesis, regarding the static behaviour from loads relevant to offshore wind turbines. The main issue in this concept is the rotational stiffness of the foundation and the combined capacity dominated by moments. The vertical bearing capacity of bucket foundations...... theory is proposed. The proposed expression applies to plane strain as well as axis-symmetric stress conditions for foundations with smooth or rough bases. A thorough experimental investigation of the static behaviour of bucket foundations subjected to combined loading is carried out. Laboratory tests...... as well as large-scale tests on bucket foundations subjected to low vertical load are performed during this work. Numerical simulations of the tests performed are carried out using the Mohr Coulomb material model and the commercial finite element code ABAQUS. Based on the present work, the finite element...

  12. Vibration of imperfect rotating disk

    Directory of Open Access Journals (Sweden)

    Půst L.

    2011-12-01

    Full Text Available This study is concerned with the theoretical and numerical calculations of the flexural vibrations of a bladed disk. The main focus of this study is to elaborate the basic background for diagnostic and identification methods for ascertaining the main properties of the real structure or an experimental model of turbine disks. The reduction of undesirable vibrations of blades is proposed by using damping heads, which on the experimental model of turbine disk are applied only on a limited number of blades. This partial setting of damping heads introduces imperfection in mass, stiffness and damping distribution on the periphery and leads to more complicated dynamic properties than those of a perfect disk. Calculation of FEM model and analytic—numerical solution of disk behaviour in the limited (two modes frequency range shows the splitting of resonance with an increasing speed of disk rotation. The spectrum of resonance is twice denser than that of a perfect disk.

  13. Galaxy cluster's rotation

    CERN Document Server

    Manolopoulou, Maria

    2016-01-01

    We study the possible rotation of cluster galaxies, developing, testing and applying a novel algorithm which identifies rotation, if such does exits, as well as its rotational centre, its axis orientation, rotational velocity amplitude and, finally, the clockwise or counterclockwise direction of rotation on the plane of the sky. To validate our algorithms we construct realistic Monte-Carlo mock rotating clusters and confirm that our method provides robust indications of rotation. We then apply our methodology on a sample of Abell clusters with z<~0.1 with member galaxies selected from the SDSS DR10 spectroscopic database. We find that ~35% of our clusters are rotating when using a set of strict criteria, while loosening the criteria we find this fraction increasing to ~48%. We correlate our rotation indicators with the cluster dynamical state, provided either by their Bautz-Morgan type or by their X-ray isophotal shape and find for those clusters showing rotation that the significance and strength of their...

  14. Classical behaviour of the Dirac bispinor

    CERN Document Server

    Bell, S B M; Díaz, B M; Bell, Sarah B. M.; Cullerne, John P.; Diaz, Bernard M.

    2000-01-01

    It is usually supposed that the Dirac and radiation equations predict that the phase of a fermion will rotate through half the angle through which the fermion is rotated, which means, via the measured dynamical and geometrical phase factors, that the fermion must have a half-integral spin. We demonstrate that this is not the case and that the identical relativistic quantum mechanics can also be derived with the phase of the fermion rotating through the same angle as does the fermion itself. Under spatial rotation and Lorentz transformation the bispinor transforms as a four-vector like the potential and Dirac current. Previous attempts to provide this form of transformational behaviour have foundered because a satisfactory current could not be derived.(14)

  15. Effects of rotation amplitude on arm movement when rotating a spherical object.

    Science.gov (United States)

    Lardy, Julien; Beurier, Georges; Wang, Xuguang

    2012-01-01

    Arm movements when rotating a spherical object were experimentally investigated. Twelve volunteers participated in the experiment and were asked to rotate a sphere for a large range of amplitude. Results showed that subjects anticipated their posture at the beginning of object manipulation even for low rotation amplitudes. The way of anticipation strongly depended on rotation direction. The end-state comfort hypothesis, effects of joint limits and principle of minimum work were examined for explaining motion control. The anticipation would ensure a better end-state comfort while avoiding joint limits in case of higher amplitude of object rotation. Meanwhile, it should not deteriorate the comfort at the beginning of manipulation too much. High postural variability for low rotation amplitude tasks suggested that there might exist a range of postures of similar level of comfort. These findings will be useful in developing human behaviour-based motion simulations for digital human. Arm movement was investigated when rotating a spherical object with a large range of amplitude. The end-state comfort hypothesis, effects of joint limits and principle of minimum work were examined for explaining motion control. Results will be helpful for a better design of rotary controls and for developing motion simulation algorithms.

  16. Pattern formation in rotating Bénard convection

    Science.gov (United States)

    Fantz, M.; Friedrich, R.; Bestehorn, M.; Haken, H.

    1992-12-01

    Using an extension of the Swift-Hohenberg equation we study pattern formation in the Bénard experiment close to the onset of convection in the case of rotating cylindrical fluid containers. For small Taylor numbers we emphasize the existence of slowly rotating patterns and describe behaviour exhibiting defect motion. Finally, we study pattern formation close to the Küppers-Lortz instability. The instability is nucleated at defects and proceeds through front propagation into the bulk patterns.

  17. Faraday resonance in dynamical bar instability of differentially rotating stars

    CERN Document Server

    Saijo, Motoyuki

    2008-01-01

    We investigate the nonlinear behaviour of the dynamically unstable rotating star for the bar mode by three-dimensional hydrodynamics in Newtonian gravity. We find that an oscillation along the rotation axis is induced throughout the growth of the unstable bar mode, and that its characteristic frequency is twice as that of the bar mode, which oscillates mainly along the equatorial plane. A possibility to observe Faraday resonance in gravitational waves is demonstrated and discussed.

  18. A rotating charged black hole solution in () gravity

    Indian Academy of Sciences (India)

    Alexis Larrañaga

    2012-05-01

    In the context of () theories of gravity, we address the problem of finding a rotating charged black hole solution in the case of constant curvature. A new metric is obtained by solving the field equations and we show that its behaviour is typical of a rotating charged source. In addition, we analyse the thermodynamics of the new black hole. The results ensure that the thermodynamical properties in () gravities are qualitatively similar to those of standard General Relativity.

  19. Relativistic Rotating Vector Model

    CERN Document Server

    Lyutikov, Maxim

    2016-01-01

    The direction of polarization produced by a moving source rotates with the respect to the rest frame. We show that this effect, induced by pulsar rotation, leads to an important correction to polarization swings within the framework of rotating vector model (RVM); this effect has been missed by previous works. We construct relativistic RVM taking into account finite heights of the emission region that lead to aberration, time-of-travel effects and relativistic rotation of polarization. Polarizations swings at different frequencies can be used, within the assumption of the radius-to-frequency mapping, to infer emission radii and geometry of pulsars.

  20. High-accuracy determination for optical indicatrix rotation in ferroelectric DTGS

    OpenAIRE

    O.S.Kushnir; O.A.Bevz; O.G.Vlokh

    2000-01-01

    Optical indicatrix rotation in deuterated ferroelectric triglycine sulphate is studied with the high-accuracy null-polarimetric technique. The behaviour of the effect in ferroelectric phase is referred to quadratic spontaneous electrooptics.

  1. Deconstructing Mental Rotation

    DEFF Research Database (Denmark)

    Larsen, Axel

    2014-01-01

    A random walk model of the classical mental rotation task is explored in two experiments. By assuming that a mental rotation is repeated until sufficient evidence for a match/mismatch is obtained, the model accounts for the approximately linearly increasing reaction times (RTs) on positive trials...... alignment take place during fixations at very high speed....

  2. Short-rotation plantations

    Science.gov (United States)

    Philip E. Pope; Jeffery O. Dawson

    1989-01-01

    Short-rotation plantations offer several advantages over longer, more traditional rotations. They enhance the natural productivity of better sites and of tree species with rapid juvenile growth. Returns on investment are realized in a shorter period and the risk of loss is reduced compared with long term investments. Production of wood and fiber can be maximized by...

  3. Faraday rotation measure synthesis

    NARCIS (Netherlands)

    Brentjens, MA; de Bruyn, AG

    2005-01-01

    We extend the rotation measure work of Burn ( 1966, MNRAS, 133, 67) to the cases of limited sampling of lambda(2) space and non-constant emission spectra. We introduce the rotation measure transfer function (RMTF), which is an excellent predictor of n pi ambiguity problems with the lambda(2) coverag

  4. SMAP Faraday Rotation

    Science.gov (United States)

    Le Vine, David

    2016-01-01

    Faraday rotation is a change in the polarization as signal propagates through the ionosphere. At L-band it is necessary to correct for this change and measurements are made on the spacecraft of the rotation angle. These figures show that there is good agreement between the SMAP measurements (blue) and predictions based on models (red).

  5. A Rotating Quantum Vacuum

    CERN Document Server

    De Lorenci, V A

    1996-01-01

    We investigate which mapping we have to use to compare measurements made in a rotating frame to those made in an inertial frame. Using a "Lorentz-like" coordinate transformation we obtain that creation-anihilation operators of a massless scalar field in the rotating frame are not the same as those of an inertial observer. This leads to a new vacuum state (a rotating vacuum) which is a superposition of positive and negative frequency Minkowski particles. After this, introducing an apparatus device coupled linearly with the field we obtain that there is a strong correlation between number of rotating particles (in a given state) obtained via canonical quantization and via response function of the rotating detector. Finally, we analyse polarization effects in circular accelerators in the proper frame of the electron making a connection with the inertial frame point of view.

  6. Uniformly rotating neutron stars

    CERN Document Server

    Boshkayev, Kuantay

    2016-01-01

    In this chapter we review the recent results on the equilibrium configurations of static and uniformly rotating neutron stars within the Hartle formalism. We start from the Einstein-Maxwell-Thomas-Fermi equations formulated and extended by Belvedere et al. (2012, 2014). We demonstrate how to conduct numerical integration of these equations for different central densities ${\\it \\rho}_c$ and angular velocities $\\Omega$ and compute the static $M^{stat}$ and rotating $M^{rot}$ masses, polar $R_p$ and equatorial $R_{\\rm eq}$ radii, eccentricity $\\epsilon$, moment of inertia $I$, angular momentum $J$, as well as the quadrupole moment $Q$ of the rotating configurations. In order to fulfill the stability criteria of rotating neutron stars we take into considerations the Keplerian mass-shedding limit and the axisymmetric secular instability. Furthermore, we construct the novel mass-radius relations, calculate the maximum mass and minimum rotation periods (maximum frequencies) of neutron stars. Eventually, we compare a...

  7. On galaxy spiral arms' nature as revealed by rotation frequencies

    NARCIS (Netherlands)

    Roca-Fabrega, Santi; Valenzuela, Octavio; Figueras, Francesca; Romero-Gomez, Merce; Velazquez, Hector; Antoja Castelltort, Teresa; Pichardo, Barbara

    2013-01-01

    High-resolution N-body simulations using different codes and initial condition techniques reveal two different behaviours for the rotation frequency of transient spiral arms like structures. Whereas unbarred discs present spiral arms nearly corotating with disc particles, strong barred models (bulge

  8. Optical vibration and deviation measurement of rotating machine parts

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV).

  9. Identifying prototypical components in behaviour using clustering algorithms.

    Directory of Open Access Journals (Sweden)

    Elke Braun

    Full Text Available Quantitative analysis of animal behaviour is a requirement to understand the task solving strategies of animals and the underlying control mechanisms. The identification of repeatedly occurring behavioural components is thereby a key element of a structured quantitative description. However, the complexity of most behaviours makes the identification of such behavioural components a challenging problem. We propose an automatic and objective approach for determining and evaluating prototypical behavioural components. Behavioural prototypes are identified using clustering algorithms and finally evaluated with respect to their ability to represent the whole behavioural data set. The prototypes allow for a meaningful segmentation of behavioural sequences. We applied our clustering approach to identify prototypical movements of the head of blowflies during cruising flight. The results confirm the previously established saccadic gaze strategy by the set of prototypes being divided into either predominantly translational or rotational movements, respectively. The prototypes reveal additional details about the saccadic and intersaccadic flight sections that could not be unravelled so far. Successful application of the proposed approach to behavioural data shows its ability to automatically identify prototypical behavioural components within a large and noisy database and to evaluate these with respect to their quality and stability. Hence, this approach might be applied to a broad range of behavioural and neural data obtained from different animals and in different contexts.

  10. Chaotic rotation of Hyperion?

    Science.gov (United States)

    Binzel, R. P.; Green, J. R.; Opal, C. B.

    1986-01-01

    Thomas et al. (1984) analyzed 14 Voyager 2 images of Saturn's satellite Hyperion and interpreted them to be consistent with a coherent (nonchaotic) rotation period of 13.1 days. This interpretation was criticized by Peale and Wisdom (1984), who argued that the low sampling frequency of Voyager data does not allow chaotic or nonchaotic rotation to be distinguished. New observations obtained with a higher sampling frequency are reported here which conclusively show that the 13.1 day period found by Thomas et al. was not due to coherent rotation.

  11. A rotating quantum vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Lorenci, V.A. de; Svaiter, N.F. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    1996-11-01

    It was investigated which mapping has to be used to compare measurements made in a rotating frame to those made in an inertial frame. Using a non-Galilean coordinate transformation, the creation-annihilation operators of a massive scalar field in the rotating frame are not the same as those of an inertial observer. This leads to a new vacuum state(a rotating vacuum) which is a superposition of positive and negative frequency Minkowski particles. Polarization effects in circular accelerators in the proper frame of the electron making a connection with the inertial frame point of view were analysed. 65 refs.

  12. Rotator Cuff Injuries

    Science.gov (United States)

    ... cuff are common. They include tendinitis, bursitis, and injuries such as tears. Rotator cuff tendons can become ... cuff depends on age, health, how severe the injury is, and how long you've had the ...

  13. Fractal Aggregation Under Rotation

    Institute of Scientific and Technical Information of China (English)

    WU Feng-Min; WU Li-Li; LU Hang-Jun; LI Qiao-Wen; YE Gao-Xiang

    2004-01-01

    By means of the Monte Carlo simulation, a fractal growth model is introduced to describe diffusion-limited aggregation (DLA) under rotation. Patterns which are different from the classical DLA model are observed and the fractal dimension of such clusters is calculated. It is found that the pattern of the clusters and their fractal dimension depend strongly on the rotation velocity of the diffusing particle. Our results indicate the transition from fractal to non-fractal behavior of growing cluster with increasing rotation velocity, i.e. for small enough angular velocity ω the fractal dimension decreases with increasing ω, but then, with increasing rotation velocity, the fractal dimension increases and the cluster becomes compact and tends to non-fractal.

  14. Fractal Aggregation Under Rotation

    Institute of Scientific and Technical Information of China (English)

    WUFeng-Min; WULi-Li; LUHang-Jun; LIQiao-Wen; YEGao-Xiang

    2004-01-01

    By means of the Monte Carlo simulation, a fractal growth model is introduced to describe diffusion-limited aggregation (DLA) under rotation. Patterns which are different from the classical DLA model are observed and the fractal dimension of such clusters is calculated. It is found that the pattern of the clusters and their fractal dimension depend strongly on the rotation velocity of the diffusing particle. Our results indicate the transition from fractal to non-fractal behavior of growing cluster with increasing rotation velocity, i.e. for small enough angular velocity ω; thefractal dimension decreases with increasing ω;, but then, with increasing rotation velocity, the fractal dimension increases and the cluster becomes compact and tends to non-fractal.

  15. Solar rotation gravitational moments

    Directory of Open Access Journals (Sweden)

    A. Ajabshirizadeh

    2005-09-01

    Full Text Available   Gravitational multipole moments of the Sun are still poorly known. Theoretically, the difficulty is mainly due to the differential rotation for which the velocity rate varies both on the surface and with the depth. From an observational point of view, the multipole moments cannot be directly measured. However, recent progresses have been made proving the existence of a strong radial differential rotation in a thin layer near the solar surface (the leptocline. Applying the theory of rotating stars, we will first compute values of J2 and J4 taking into account the radial gradient of rotation, then we will compare these values with the existing ones, giving a more complete review. We will explain some astrophysical outcomes, mainly on the relativistic Post Newtonian parameters. Finally we will conclude by indicating how space experiments (balloon SDS flights, Golf NG, Beppi-Colombo, Gaia... will be essential to unambiguously determine these parameters.

  16. ANALYSIS OF DEPOSIT MAINTENANCE IN ROTATING DRUMS

    Directory of Open Access Journals (Sweden)

    Krystian Malek

    2015-10-01

    Full Text Available Rotating drums are used to grinding, drying, mixing, screening, granulating and other processes in environmental engineering. Depending on the nature of the process they can be equipped with additional devices to support the processes. In this work, the effect of drum surface roughness on the behaviour of the feed during drumming. For this purpose, three types of bottom coverings with grain size of 40, 80 and 120 were used. In the experiment the methodology of sequential image analysis using PIV software was applied. The results of theoretical calculations and experimental works have shown significant discrepancies (of approx. 46% of speed characteristics for the minimum speed of the drum and smaller (amounting to approx. 5% for the critical speed. In case of change in the particle size of the drum coverings, there were no significant differences in the behaviour of the feed.

  17. Electromagnetic rotational actuation.

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Alexander Lee

    2010-08-01

    There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.

  18. Rotational spectrum of phenylglycinol

    Science.gov (United States)

    Simão, Alcides; Peña, Isabel; Cabezas, Carlos; Alonso, José L.

    2014-11-01

    Solid samples of phenylglycinol were vaporized by laser ablation and investigated through rotational spectroscopy in a supersonic expansion using two different techniques: chirped pulse Fourier transform microwave spectroscopy and narrow band molecular beam Fourier transform microwave spectroscopy. One conformer, bearing an O-H···N and an N-H···π intramolecular hydrogen bonds, could be successfully identified by comparison of the experimental rotational and 14N nuclear quadruple coupling constants with those predicted theoretically.

  19. Earth rotation and geodynamics

    OpenAIRE

    Bogusz Janusz; Brzezinski Aleksander; Kosek Wieslaw; Nastula Jolanta

    2015-01-01

    This paper presents the summary of research activities carried out in Poland in 2011-2014 in the field of Earth rotation and geodynamics by several Polish research institutions. It contains a summary of works on Earth rotation, including evaluation and prediction of its parameters and analysis of the related excitation data as well as research on associated geodynamic phenomena such as geocentre motion, global sea level change and hydrological processes. The second part of the paper deals wit...

  20. Scaling regimes in spherical shell rotating convection

    CERN Document Server

    Gastine, T; Aubert, J

    2016-01-01

    Rayleigh-B\\'enard convection in rotating spherical shells can be considered as a simplified analogue of many astrophysical and geophysical fluid flows. Here, we use three-dimensional direct numerical simulations to study this physical process. We construct a dataset of more than 200 numerical models that cover a broad parameter range with Ekman numbers spanning $3\\times 10^{-7} \\leq E \\leq 10^{-1}$, Rayleigh numbers within the range $10^3 < Ra < 2\\times 10^{10}$ and a Prandtl number unity. We investigate the scaling behaviours of both local (length scales, boundary layers) and global (Nusselt and Reynolds numbers) properties across various physical regimes from onset of rotating convection to weakly-rotating convection. Close to critical, the convective flow is dominated by a triple force balance between viscosity, Coriolis force and buoyancy. For larger supercriticalities, a subset of our numerical data approaches the asymptotic diffusivity-free scaling of rotating convection $Nu\\sim Ra^{3/2}E^{2}$ in ...

  1. Organizational Behaviour in Construction

    DEFF Research Database (Denmark)

    Kreiner, Kristian

    2013-01-01

    Review of: Organizational Behaviour in Construction / Anthony Walker (Wiley-Blackwell,2011 336 pp)......Review of: Organizational Behaviour in Construction / Anthony Walker (Wiley-Blackwell,2011 336 pp)...

  2. Recycling as moral behaviour

    DEFF Research Database (Denmark)

    Thøgersen, John

    of Reasoned Action (TRA) with regard to understanding recycling behaviour. Further, examples of misleading policy conclusions are discussed suggested that within the framework of cognitive psychology, Schwartz's model of altruistic behaviour offers a more satisfying starting point for understanding recycling......It is argued in this paper that in the affluent, industrial societies, environmental behaviours like recycling are typically classified within ""the domain of morality"" in people's minds. Intentions regarding these types of behaviours are not ba a thorough - conscious or unconscious - calculation...

  3. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    Science.gov (United States)

    Hilal, Sadek K.; Sampson, William B.; Leonard, Edward F.

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  4. Organizational Behaviour Study Material

    OpenAIRE

    P. Sreeramana Aithal

    2016-01-01

    An overview of Organizational Behaviour – History of Organisational Behaviour and its  emergence as a disciple-emerging perspective Organizational Behaviour.  Individual process in organisation – Learning, perception and attribution- Individual differences - Basic concepts of motivation - Advanced concepts of motivation. Group process in Organisation – Group dynamics, leadership theories - Power, politics and conflict - inter- personal communication. Enhancing individu...

  5. Rapidly rotating red giants

    CERN Document Server

    Gehan, Charlotte; Michel, Eric

    2016-01-01

    Stellar oscillations give seismic information on the internal properties of stars. Red giants are targets of interest since they present mixed modes, which behave as pressure modes in the convective envelope and as gravity modes in the radiative core. Mixed modes thus directly probe red giant cores, and allow in particular the study of their mean core rotation. The high-quality data obtained by CoRoT and Kepler satellites represent an unprecedented perspective to obtain thousands of measurements of red giant core rotation, in order to improve our understanding of stellar physics in deep stellar interiors. We developed an automated method to obtain such core rotation measurements and validated it for stars on the red giant branch. In this work, we particularly focus on the specific application of this method to red giants having a rapid core rotation. They show complex spectra where it is tricky to disentangle rotational splittings from mixed-mode period spacings. We demonstrate that the method based on the id...

  6. Vibrations of rotating machinery

    CERN Document Server

    Matsushita, Osami; Kanki, Hiroshi; Kobayashi, Masao; Keogh, Patrick

    2017-01-01

    This book opens with an explanation of the vibrations of a single degree-of-freedom (dof) system for all beginners. Subsequently, vibration analysis of multi-dof systems is explained by modal analysis. Mode synthesis modeling is then introduced for system reduction, which aids understanding in a simplified manner of how complicated rotors behave. Rotor balancing techniques are offered for rigid and flexible rotors through several examples. Consideration of gyroscopic influences on the rotordynamics is then provided and vibration evaluation of a rotor-bearing system is emphasized in terms of forward and backward whirl rotor motions through eigenvalue (natural frequency and damping ratio) analysis. In addition to these rotordynamics concerning rotating shaft vibration measured in a stationary reference frame, blade vibrations are analyzed with Coriolis forces expressed in a rotating reference frame. Other phenomena that may be assessed in stationary and rotating reference frames include stability characteristic...

  7. Chiral Rotational Spectroscopy

    CERN Document Server

    Cameron, Robert P; Barnett, Stephen M

    2015-01-01

    We introduce chiral rotational spectroscopy: a new technique that enables the determination of the individual optical activity polarisability components $G_{XX}'$, $G_{YY}'$, $G_{ZZ}'$, $A_{X,YZ}$, $A_{Y,ZX}$ and $A_{Z,XY}$ of chiral molecules, in a manner that reveals the enantiomeric constitution of a sample whilst yielding an incisive signal even for a racemate. Chiral rotational spectroscopy could find particular use in the analysis of molecules that are chiral by virtue of their isotopic constitution and molecules with multiple chiral centres. The principles that underpin chiral rotational spectroscopy can also be exploited in the search for molecular chirality in space, which, if found, may add weight to hypotheses that biological homochirality and indeed life itself are of cosmic origin.

  8. Chiral rotational spectroscopy

    Science.gov (United States)

    Cameron, Robert P.; Götte, Jörg B.; Barnett, Stephen M.

    2016-09-01

    We introduce chiral rotational spectroscopy, a technique that enables the determination of the orientated optical activity pseudotensor components BX X, BY Y, and BZ Z of chiral molecules, in a manner that reveals the enantiomeric constitution of a sample and provides an incisive signal even for a racemate. Chiral rotational spectroscopy could find particular use in the analysis of molecules that are chiral solely by virtue of their isotopic constitution and molecules with multiple chiral centers. A basic design for a chiral rotational spectrometer together with a model of its functionality is given. Our proposed technique offers the more familiar polarizability components αX X, αY Y, and αZ Z as by-products, which could see it find use even for achiral molecules.

  9. Rotating ice blocks

    Science.gov (United States)

    Dorbolo, Stephane; Adami, Nicolas; Grasp Team

    2014-11-01

    The motion of ice discs released at the surface of a thermalized bath was investigated. As observed in some rare events in the Nature, the discs start spinning spontaneously. The motor of this motion is the cooling of the water close to the ice disc. As the density of water is maximum at 4°C, a downwards flow is generated from the surface of the ice block to the bottom. This flow generates the rotation of the disc. The speed of rotation depends on the mass of the ice disc and on the temperature of the bath. A model has been constructed to study the influence of the temperature of the bath. Finally, ice discs were put on a metallic plate. Again, a spontaneous rotation was observed. FNRS is thanked for financial support.

  10. The optical rotator

    DEFF Research Database (Denmark)

    Tandrup, T; Gundersen, Hans Jørgen Gottlieb; Jensen, Eva B. Vedel

    1997-01-01

    The optical rotator is an unbiased, local stereological principle for estimation of cell volume and cell surface area in thick, transparent slabs, The underlying principle was first described in 1993 by Kieu Jensen (T. Microsc. 170, 45-51) who also derived an estimator of length, In this study we...... further discuss the methods derived from this principle and present two new local volume estimators. The optical rotator benefits from information obtained in all three dimensions in thick sections but avoids over-/ underprojection problems at the extremes of the cell. Using computer-assisted microscopes...... the extra measurements demand minimal extra effort and make this estimator even more efficient when it comes to estimation of individual cell size than many of the previous local estimators, We demonstrate the principle of the optical rotator in an example (the cells in the dorsal root ganglion of the rat...

  11. Rotation of cometary meteoroids

    CERN Document Server

    Capek, David

    2014-01-01

    The aim of this study is to estimate the rotational characteristics of meteoroids after their release from a comet during normal activity. The results can serve as initial conditions for further analyses of subsequent evolution of rotation in the interplanetary space. A sophisticated numerical model was applied to meteoroids ejected from 2P/Encke comet. The meteoroid shapes were approximated by polyhedrons with several thousands of surface elements, which have been determined by 3D laser scanning method of 36 terrestrial rock samples. These samples came from three distinct sets with different origin and shape characteristics. Two types of gas-meteoroid interactions (diffuse and specular reflection of gas molecules from the surface of meteoroid) and three gas ejection models (leading to very different ejection velocities) were assumed. The rotational characteristics of ejected meteoroid population were obtained by numerical integration of equations of motion with random initial conditions and random shape sele...

  12. Rotation periods and seismic ages of KOIs - comparison with stars without detected planets from Kepler observations

    Science.gov (United States)

    Ceillier, T.; van Saders, J.; García, R. A.; Metcalfe, T. S.; Creevey, O.; Mathis, S.; Mathur, S.; Pinsonneault, M. H.; Salabert, D.; Tayar, J.

    2016-02-01

    One of the most difficult properties to derive for stars is their age. For cool main-sequence stars, gyrochronology relations can be used to infer stellar ages from measured rotation periods and Hertzsprung Russell diagram positions. These relations have few calibrators with known ages for old, long rotation period stars. There is a significant sample of old Kepler objects of interest, or KOIs, which have both measurable surface rotation periods and precise asteroseismic measurements from which ages can be accurately derived. In this work, we determine the age and the rotation period of solar-like pulsating KOIs to both compare the rotation properties of stars with and without known planets and enlarge the gyrochronology calibration sample for old stars. We use Kepler photometric light curves to derive the stellar surface rotation periods while ages are obtained with asteroseismology using the Asteroseismic Modelling Portal in which individual mode frequencies are combined with high-resolution spectroscopic parameters. We thus determine surface rotation periods and ages for 11 planet-hosting stars, all over 2 Gyr old. We find that the planet-hosting stars exhibit a rotational behaviour that is consistent with the latest age-rotation models and similar to the rotational behaviour of stars without detected planets. We conclude that these old KOIs can be used to test and calibrate gyrochronology along with stars not known to host planets.

  13. Waves in geomaterials exhibiting negative stiffness behaviour

    Science.gov (United States)

    Esin, Maxim; Dyskin, Arcady; Pasternak, Elena

    2016-04-01

    Negative stiffness denotes the type of material behaviour when the force applied to the body decreases the body's deformation increases. Some geomaterials, for instance, rocks, demonstrate behaviour of this type at certain loads: during the compression tests the loading curves exhibit descending branch (post-peak softening). One of the possible mechanisms of the negative stiffness appearance in geomaterials is rotation of non-spherical grains. It is important to emphasize that in this case the descending branch may be reversible given that the testing machine is stiff enough (in general case it means an importance of boundary conditions). Existence of geomaterials with a negative modulus associated with rotations may have significant importance. In particular, important is understanding of the wave propagation in such materials. We study the stability of geomaterials with negative stiffness inclusions and wave propagation in it using two approaches: Cosserat continuum and discrete mass-spring models. In both cases we consider the rotational degrees of freedom in addition to the conventional translational ones. We show that despite non positiveness of the energy the materials with negative stiffness elements can be stable if certain conditions are met. In the case of Cosserat continuum the Cosserat shear modulus (the modulus relating the non-symmetrical part of shear stress and internal rotations) is allowed to assume negative values as long as its value does not exceed the value of the standard (positive) shear modulus. In the case of discrete mass-spring systems (with translational and rotational springs) the concentration of negative stiffness springs and the absolute values of negative spring stiffness are limited. The critical concentration when the system loses stability and the amplitude of the oscillations tends to infinity is equal to 1/2 and 3/5 for two- and three-dimensional cases respectively.

  14. Effect of rotation on a rotating hot-wire sensor

    Science.gov (United States)

    Hah, C.; Lakshminarayana, B.

    1978-01-01

    An investigation was conducted to discern the effects of centrifugal and Coriolis forces on a rotating hot-wire. The probe was calibrated in a wind tunnel as well as in a rotating mode. The effect of rotation was found to be negligibly small. A small change in cold resistance (1.5%) was observed in the rotating wire. The rotation seems to have a negligible effect on the fluid mechanics, heat transfer and material characteristics of the wire. This is a significant conclusion in view of the potential application of the hot-wire probe in a rotating passage (such as turbomachinery).

  15. Statistics of the elastic behaviour of granular materials

    NARCIS (Netherlands)

    Kruyt, N.P.; Rothenburg, L.

    2001-01-01

    The elastic behaviour of isotropic assemblies of granular materials consisting of two-dimensional, bonded and non-rotating particles is studied from the micromechanical viewpoint. Discrete element simulations have been performed of assemblies of 50,000 particles with various coordination numbers (av

  16. The Spatiale Rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan

    2009-01-01

    The inherent demand for unbiasedness for some stereological estimators imposes a demand of not only positional uniform randomness but also isotropic randomness, i.e. directional uniform randomness. In order to comply with isotropy, one must perform a random rotation of the object of interest befo...

  17. Rotator Cuff Injuries.

    Science.gov (United States)

    Connors, G. Patrick

    Many baseball players suffer from shoulder injuries related to the rotator cuff muscles. These injuries may be classified as muscular strain, tendonitis or tenosynovitis, and impingement syndrome. Treatment varies from simple rest to surgery, so it is important to be seen by a physician as soon as possible. In order to prevent these injuries, the…

  18. Rotator Cuff Injuries.

    Science.gov (United States)

    Connors, G. Patrick

    Many baseball players suffer from shoulder injuries related to the rotator cuff muscles. These injuries may be classified as muscular strain, tendonitis or tenosynovitis, and impingement syndrome. Treatment varies from simple rest to surgery, so it is important to be seen by a physician as soon as possible. In order to prevent these injuries, the…

  19. Compact rotating cup anemometer

    Science.gov (United States)

    Wellman, J. B.

    1968-01-01

    Compact, collapsible rotating cup anemometer is used in remote locations where portability and durability are factors in the choice of equipment. This lightweight instrument has a low wind-velocity threshold, is capable of withstanding large mechanical shocks while in its stowed configuration, and has fast response to wind fluctuations.

  20. The rotating quantum vacuum

    CERN Document Server

    Davies, Paul Charles William; Manogue, C A; Davies, Paul C W; Dray, Tevian; Manogue, Corinne A

    1996-01-01

    We derive conditions for rotating particle detectors to respond in a variety of bounded spacetimes and compare the results with the folklore that particle detectors do not respond in the vacuum state appropriate to their motion. Applications involving possible violations of the second law of thermodynamics are briefly addressed.

  1. Rotationally Actuated Prosthetic Hand

    Science.gov (United States)

    Norton, William E.; Belcher, Jewell G., Jr.; Carden, James R.; Vest, Thomas W.

    1991-01-01

    Prosthetic hand attached to end of remaining part of forearm and to upper arm just above elbow. Pincerlike fingers pushed apart to degree depending on rotation of forearm. Simpler in design, simpler to operate, weighs less, and takes up less space.

  2. PD-pulse characteristics in rotating machine insulation

    DEFF Research Database (Denmark)

    Holbøll, Joachim; Henriksen, Mogens; Jensen, A;

    1994-01-01

    In this paper results are presented from investigations on partial discharges (PD) in insulation systems, resembling the stator insulation in high voltage rotating machines. A model, simulating a stator winding in a slot, has been developed, consisting of simple rotating machine insulation test...... bars with epoxy/mica insulation, mounted between steel sheets forming a dot, in order to investigate the fundamental behaviour of PD in insulation defects in epoxy/mica insulation and the characteristics of the resulting electrical pulses. Stator slot couplers (SSC) were used to detect pulses coming...

  3. A lumped model for rotational modes in periodic solid composites

    KAUST Repository

    Peng, Pai

    2013-10-01

    We present a lumped model to study the rotational modes in a type of two-dimensional periodic solid composites comprised of a square array of rubber-coated steel cylinders embedded in an epoxy matrix. The model captures the physical essence of rotational modes in such systems for various combinations of material parameters, and, therefore it is able to describe the transition behaviour when the system is gradually adjusted from an elastic metamaterial to an elastic phononic crystal. From the model, we can define a transition zone which separates the typical elastic metamaterials and the phononic crystals.

  4. Magnetic rotation – past, present and future

    Indian Academy of Sciences (India)

    A K Jain; Deepika Choudhury

    2010-07-01

    Magnetic-dipole rotational (MR) bands were discovered about 15 years ago without any theoretical prediction in contrast to the super-deformed (SD) bands which were predicted long ago. First identification of a quasirotational structure as MR band occurred around 1992 although Kr isotopes probably have the first set of data having the signatures of MR bands as shown by us. Our first compilation of MR bands listed 120 MR bands in 56 nuclides which have now grown to more than 180 bands in 80 nuclides. We have observed new MR bands in the = 130 mass region in 137Pr,139Nd and 135Ba nuclei. This led to the observation of the smallest MR bands in 137Pr, multiple minima in the deformation in 135Ba, coexistence of band structure based on these minima and band crossing of MR bands in = 130 region. Some of these results have been reviewed in this paper along with theoretical calculations. There are still a number of questions related to MR bands which have not been fully resolved. The role of neutrons/protons in magnetic rotation still needs to be delineated. Do the MR bands follow the ( + 1) behaviour? Are these structures as regular as normal rotational bands? How important is the existence of deformation for MR bands? We address some of these questions in this paper.

  5. Behavioural present value

    OpenAIRE

    Krzysztof Piasecki

    2013-01-01

    Impact of chosen behavioural factors on imprecision of present value is discussed here. The formal model of behavioural present value is offered as a result of this discussion. Behavioural present value is described here by fuzzy set. These considerations were illustrated by means of extensive numerical case study. Finally there are shown that in proposed model the return rate is given, as a fuzzy probabilistic set.

  6. Rethinking retailer buying behaviour

    DEFF Research Database (Denmark)

    Esbjerg, Lars

    2001-01-01

    Research of retailer buying behaviour has previously focused on the buying decision. In this paper a new approach to studying retailer buying behaviour is suggested, one which focuses on the sensemaking processes leading up to a decision being made. A research project taking a sensemaking...... perspective is outlined and the implications and expected contribution of studying retailer buying behaviour from a sensemaking perspective are discussed....

  7. Incentives and Prosocial Behaviour

    OpenAIRE

    Bénabou, Roland; Tirole, Jean

    2004-01-01

    We build a theory of prosocial behaviour that combines heterogeneity in individual altruism and greed with concerns for social reputation or self-respect. The presence of rewards or punishments creates doubt as to the true motive for which good deeds are performed, and this ‘overjustification effect’ can result in a net crowding out of prosocial behaviour by extrinsic incentives. The model also allows us to identify settings that are conducive to multiple social norms of behaviour, and those ...

  8. RoboPol: optical polarization-plane rotations and flaring activity in blazars

    Science.gov (United States)

    Blinov, D.; Pavlidou, V.; Papadakis, I. E.; Hovatta, T.; Pearson, T. J.; Liodakis, I.; Panopoulou, G. V.; Angelakis, E.; Baloković, M.; Das, H.; Khodade, P.; Kiehlmann, S.; King, O. G.; Kus, A.; Kylafis, N.; Mahabal, A.; Marecki, A.; Modi, D.; Myserlis, I.; Paleologou, E.; Papamastorakis, I.; Pazderska, B.; Pazderski, E.; Rajarshi, C.; Ramaprakash, A.; Readhead, A. C. S.; Reig, P.; Tassis, K.; Zensus, J. A.

    2016-04-01

    We present measurements of rotations of the optical polarization of blazars during the second year of operation of RoboPol, a monitoring programme of an unbiased sample of gamma-ray bright blazars specially designed for effective detection of such events, and we analyse the large set of rotation events discovered in two years of observation. We investigate patterns of variability in the polarization parameters and total flux density during the rotation events and compare them to the behaviour in a non-rotating state. We have searched for possible correlations between average parameters of the polarization-plane rotations and average parameters of polarization, with the following results: (1) there is no statistical association of the rotations with contemporaneous optical flares; (2) the average fractional polarization during the rotations tends to be lower than that in a non-rotating state; (3) the average fractional polarization during rotations is correlated with the rotation rate of the polarization plane in the jet rest frame; (4) it is likely that distributions of amplitudes and durations of the rotations have physical upper bounds, so arbitrarily long rotations are not realized in nature.

  9. Changing doctor prescribing behaviour

    DEFF Research Database (Denmark)

    Gill, P.S.; Mäkelä, M.; Vermeulen, K.M.

    1999-01-01

    The aim of this overview was to identify interventions that change doctor prescribing behaviour and to derive conclusions for practice and further research. Relevant studies (indicating prescribing as a behaviour change) were located from a database of studies maintained by the Cochrane Collabora......The aim of this overview was to identify interventions that change doctor prescribing behaviour and to derive conclusions for practice and further research. Relevant studies (indicating prescribing as a behaviour change) were located from a database of studies maintained by the Cochrane...

  10. Protective Effect of Vitamin E on Nicotine Induced Reproductive ...

    African Journals Online (AJOL)

    1Igbinedion University, Department of Physiology, School of Basic Medical Sciences, Okada, Edo State, Nigeria ... nicotine on reproductive functions in male rats. .... The experiment was conducted in accordance ..... Male infertility, clinical ...

  11. Wave-driven Rotation in Supersonically Rotating Mirrors

    Energy Technology Data Exchange (ETDEWEB)

    A. Fetterman and N.J. Fisch

    2010-02-15

    Supersonic rotation in mirrors may be produced by radio frequency waves. The waves produce coupled diffusion in ion kinetic and potential energy. A population inversion along the diffusion path then produces rotation. Waves may be designed to exploit a natural kinetic energy source or may provide the rotation energy on their own. Centrifugal traps for fusion and isotope separation may benefit from this wave-driven rotation.

  12. Rotator Cuff Injuries - Multiple Languages

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Rotator Cuff Injuries URL of this page: https://medlineplus.gov/ ... V W XYZ List of All Topics All Rotator Cuff Injuries - Multiple Languages To use the sharing features ...

  13. Speed Rotating Components

    Directory of Open Access Journals (Sweden)

    S. Wittig

    1998-01-01

    Full Text Available Cooling of high speed rotating components is a typical situation found in turbomachinery as well as in automobile engines. Accurate knowledge of discharge coefficients and heat transfer of related components is essential for the high performance of the whole engine. This can be achieved by minimized cooling air flows and avoidance of hot spots. In high speed rotating clutches for example aerodynamic investigations improving heat transfer have not been considered in the past. Advanced concepts of modern plate design try to reduce thermal loads by convective cooling methods. Therefore, secondary cooling air flows have to be enhanced by an appropriate design of the rotor stator system with orifices. CFD modelling is used to improve the basic understanding of the flow field in typical geometries used in these systems.

  14. The Spatiale Rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan

    2009-01-01

    is obeyed by randomizing the orientation of the virtual probe itself within the thick section. Overall, the benefit is that positional information is kept for any block and section of the specimen. As the Spatial Rotator is a 3D probe, data must be gathered from sections thicker than 25 micro meters to form......The inherent demand for unbiasedness for some stereological estimators imposes a demand of not only positional uniform randomness but also isotropic randomness, i.e. directional uniform randomness. In order to comply with isotropy, one must perform a random rotation of the object of interest before...... it is embedded and sectioned. This has the unfortunate side effect that all information about positioning within the object is lost for blocks and sections. For complex tissue, like the mammalian brain, this information is of utmost importance to ensure measurements are performed in the correct region...

  15. Earth rotation and geodynamics

    Science.gov (United States)

    Bogusz, Janusz; Brzezinski, Aleksander; Kosek, Wieslaw; Nastula, Jolanta

    2015-12-01

    This paper presents the summary of research activities carried out in Poland in 2011-2014 in the field of Earth rotation and geodynamics by several Polish research institutions. It contains a summary of works on Earth rotation, including evaluation and prediction of its parameters and analysis of the related excitation data as well as research on associated geodynamic phenomena such as geocentre motion, global sea level change and hydrological processes. The second part of the paper deals with monitoring of geodynamic phenomena. It contains analysis of geodynamic networks of local, and regional scale using space (GNSS and SLR) techniques, Earth tides monitoring with gravimeters and water-tube hydrostatic clinometer, and the determination of secular variation of the Earth' magnetic field.

  16. Rotational spectrum of tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk; Cabezas, Carlos, E-mail: ccabezas@qf.uva.es; Mata, Santiago, E-mail: santiago.mata@uva.es; Alonso, Josè L., E-mail: jlalonso@qf.uva.es [Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Laboratorios de Espectroscopia y Bioespectroscopia, Unidad Asociada CSIC, Parque Científico Uva, Universidad de Valladolid, 47011 Valladolid (Spain)

    2014-05-28

    The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

  17. Rotational Spectrum of Tryptophan

    Science.gov (United States)

    Sanz, M. Eugenia; Cabezas, Carlos; Mata, Santiago; Alonso, José L.

    2014-06-01

    The rotational spectrum of the natural amino acid tryptophan has been observed using a recently constructed LA-MB-FTMW spectrometer, specifically designed to optimize the detection of heavier molecules at a lower frequency range. Independent analyses of the rotational spectra of individual conformers have conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The experimental values of the 14N nuclear quadrupole coupling constants have been found capital in the discrimination of the conformers. Both observed conformers are stabilized by a O-H\\cdotsN hydrogen bond in the side chain and a N-H\\cdotsπ interaction forming a chain that reinforces the strength of hydrogen bonds through cooperative effects.

  18. A Translational Polarization Rotator

    CERN Document Server

    Chuss, David T; Pisano, Giampaolo; Ackiss, Sheridan; U-Yen, Kongpop; Ng, Ming wah

    2012-01-01

    We explore a free-space polarization modulator in which a variable phase introduction between right- and left-handed circular polarization components is used to rotate the linear polarization of the outgoing beam relative to that of the incoming beam. In this device, the polarization states are separated by a circular polarizer that consists of a quarter-wave plate in combination with a wire grid. A movable mirror is positioned behind and parallel to the circular polarizer. As the polarizer-mirror distance is separated, an incident linear polarization will be rotated through an angle that is proportional to the introduced phase delay. We demonstrate a prototype device that modulates Stokes Q and U over a 20% bandwidth.

  19. The Thomas rotation

    CERN Document Server

    Costella, J P; Rawlinson, A A; Costella, John P.; Kellar, Bruce H. J. Mc; Rawlinson, Andrew A.

    2001-01-01

    We review why the Thomas rotation is a crucial facet of special relativity, that is just as fundamental, and just as "unintuitive" and "paradoxical", as such traditional effects as length contraction, time dilation, and the ambiguity of simultaneity. We show how this phenomenon can be quite naturally introduced and investigated in the context of a typical introductory course on special relativity, in a way that is appropriate for, and completely accessible to, undergraduate students. We also demonstrate, in a more advanced section aimed at the graduate student studying the Dirac equation and relativistic quantum field theory, that careful consideration of the Thomas rotation will become vital as modern experiments in particle physics continue to move from unpolarized to polarized cross-sections.

  20. Rotator cuff tendon connections with the rotator cable.

    Science.gov (United States)

    Rahu, Madis; Kolts, Ivo; Põldoja, Elle; Kask, Kristo

    2017-07-01

    The literature currently contains no descriptions of the rotator cuff tendons, which also describes in relation to the presence and characteristics of the rotator cable (anatomically known as the ligamentum semicirculare humeri). The aim of the current study was to elucidate the detailed anatomy of the rotator cuff tendons in association with the rotator cable. Anatomic dissection was performed on 21 fresh-frozen shoulder specimens with an average age of 68 years. The rotator cuff tendons were dissected from each other and from the glenohumeral joint capsule, and the superior glenohumeral, coracohumeral, coracoglenoidal and semicircular (rotator cable) ligaments were dissected. Dissection was performed layer by layer and from the bursal side to the joint. All ligaments and tendons were dissected in fine detail. The rotator cable was found in all specimens. It was tightly connected to the supraspinatus (SSP) tendon, which was partly covered by the infraspinatus (ISP) tendon. The posterior insertion area of the rotator cable was located in the region between the middle and inferior facets of the greater tubercle of the humerus insertion areas for the teres minor (TM), and ISP tendons were also present and fibres from the SSP extended through the rotator cable to those areas. The connection between the rotator cable and rotator cuff tendons is tight and confirms the suspension bridge theory for rotator cuff tears in most areas between the SSP tendons and rotator cable. In its posterior insertion area, the rotator cable is a connecting structure between the TM, ISP and SSP tendons. These findings might explain why some patients with relatively large rotator cuff tears can maintain seamless shoulder function.

  1. Neural rotational speed control for wave energy converters

    Science.gov (United States)

    Amundarain, M.; Alberdi, M.; Garrido, A. J.; Garrido, I.

    2011-02-01

    Among the benefits arising from an increasing use of renewable energy are: enhanced security of energy supply, stimulation of economic growth, job creation and protection of the environment. In this context, this study analyses the performance of an oscillating water column device for wave energy conversion in function of the stalling behaviour in Wells turbines, one of the most widely used turbines in wave energy plants. For this purpose, a model of neural rotational speed control system is presented, simulated and implemented. This scheme is employed to appropriately adapt the speed of the doubly-fed induction generator coupled to the turbine according to the pressure drop entry, so as to avoid the undesired stalling behaviour. It is demonstrated that the proposed neural rotational speed control design adequately matches the desired relationship between the slip of the doubly-fed induction generator and the pressure drop input, improving the power generated by the turbine generator module.

  2. Properties of Rotating Neutron Star

    Directory of Open Access Journals (Sweden)

    Shailesh K. Singh

    2015-08-01

    Full Text Available Using the nuclear equation of states for a large variety of relativistic and non-relativistic force parameters, we calculate the static and rotating masses and radii of neutron stars. From these equation of states, we evaluate the properties of rotating neutron stars, such as rotational frequencies, moment of inertia, quadrupole deformation parameter, rotational ellipticity and gravitational wave strain amplitude. The estimated gravitational wave strain amplitude of the star is found to be~sim 10-23.

  3. Broadband Rotational Spectroscopy

    Science.gov (United States)

    Pate, Brooks

    2014-06-01

    The past decade has seen several major technology advances in electronics operating at microwave frequencies making it possible to develop a new generation of spectrometers for molecular rotational spectroscopy. High-speed digital electronics, both arbitrary waveform generators and digitizers, continue on a Moore's Law-like development cycle that started around 1993 with device bandwidth doubling about every 36 months. These enabling technologies were the key to designing chirped-pulse Fourier transform microwave (CP-FTMW) spectrometers which offer significant sensitivity enhancements for broadband spectrum acquisition in molecular rotational spectroscopy. A special feature of the chirped-pulse spectrometer design is that it is easily implemented at low frequency (below 8 GHz) where Balle-Flygare type spectrometers with Fabry-Perot cavity designs become technologically challenging due to the mirror size requirements. The capabilities of CP-FTMW spectrometers for studies of molecular structure will be illustrated by the collaborative research effort we have been a part of to determine the structures of water clusters - a project which has identified clusters up to the pentadecamer. A second technology trend that impacts molecular rotational spectroscopy is the development of high power, solid state sources in the mm-wave/THz regions. Results from the field of mm-wave chirped-pulse Fourier transform spectroscopy will be described with an emphasis on new problems in chemical dynamics and analytical chemistry that these methods can tackle. The third (and potentially most important) technological trend is the reduction of microwave components to chip level using monolithic microwave integrated circuits (MMIC) - a technology driven by an enormous mass market in communications. Some recent advances in rotational spectrometer designs that incorporate low-cost components will be highlighted. The challenge to the high-resolution spectroscopy community - as posed by Frank De

  4. Rotating housing turbine

    Energy Technology Data Exchange (ETDEWEB)

    Allouche, Erez; Jaganathan, Arun P.

    2016-10-11

    The invention is a new turbine structure having a housing that rotates. The housing has a sidewall, and turbine blades are attached to a sidewall portion. The turbine may be completely open in the center, allowing space for solids and debris to be directed out of the turbine without jamming the spinning blades/sidewall. The turbine may be placed in a generator for generation of electrical current.

  5. Chaotic Rotation of Nereid

    Science.gov (United States)

    Dobrovolskis, Anthony R.; Cuzzi, Jeffrey N. (Technical Monitor)

    1995-01-01

    The shape and spin of Neptune's outermost satellite Nereid are still unknown. Ground-based photometry indicates large brightness variations, but different observers report very different lightcurve amplitudes and periods. On the contrary, Voyager 2 images spanning 12 days show no evidence of variations greater than 0.1 mag. The latter suggest either that Nereid is nearly spherical, or that it is rotating slowly. We propose that tides have already despun Nereid's rotation to a period of a few weeks, during the time before the capture of Triton when Nereid was closer to Neptune. Since Nereid reached its present orbit, tides have further despun Nereid to a period on the order of a month. For Nereid's orbital eccentricity of 0.75, tidal evolution ceases when the spin period is still approximately 1/8 of the orbital period. Furthermore, the synchronous resonance becomes quite weak for such high eccentricities, along with other low-order spin orbit commensurabilities. In contrast, high-order resonances become very strong particularly the 6:1, 6.5:1, 7:1, 7.5:1, and 8:1 spin states. If Nereid departs by more than approximately 1% from a sphere, however, these resonances overlap, generating chaos. Our simulations show that Nereid is likely to be in chaotic rotation for any spin period longer than about 2 weeks.

  6. Snakes and spin rotators

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.Y.

    1990-06-18

    The generalized snake configuration offers advantages of either shorter total snake length and smaller orbit displacement in the compact configuration or the multi-functions in the split configuration. We found that the compact configuration can save about 10% of the total length of a snake. On other hand, the spilt snake configuration can be used both as a snake and as a spin rotator for the helicity state. Using the orbit compensation dipoles, the spilt snake configuration can be located at any distance on both sides of the interaction point of a collider provided that there is no net dipole rotation between two halves of the snake. The generalized configuration is then applied to the partial snake excitation. Simple formula have been obtained to understand the behavior of the partial snake. Similar principle can also be applied to the spin rotators. We also estimate the possible snake imperfections are due to various construction errors of the dipole magnets. Accuracy of field error of better than 10{sup {minus}4} will be significant. 2 refs., 5 figs.

  7. Bioreactor rotating wall vessel

    Science.gov (United States)

    2001-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.

  8. Rotating regular black holes

    Energy Technology Data Exchange (ETDEWEB)

    Bambi, Cosimo, E-mail: bambi@fudan.edu.cn; Modesto, Leonardo, E-mail: lmodesto@fudan.edu.cn

    2013-04-25

    The formation of spacetime singularities is a quite common phenomenon in General Relativity and it is regulated by specific theorems. It is widely believed that spacetime singularities do not exist in Nature, but that they represent a limitation of the classical theory. While we do not yet have any solid theory of quantum gravity, toy models of black hole solutions without singularities have been proposed. So far, there are only non-rotating regular black holes in the literature. These metrics can be hardly tested by astrophysical observations, as the black hole spin plays a fundamental role in any astrophysical process. In this Letter, we apply the Newman–Janis algorithm to the Hayward and to the Bardeen black hole metrics. In both cases, we obtain a family of rotating solutions. Every solution corresponds to a different matter configuration. Each family has one solution with special properties, which can be written in Kerr-like form in Boyer–Lindquist coordinates. These special solutions are of Petrov type D, they are singularity free, but they violate the weak energy condition for a non-vanishing spin and their curvature invariants have different values at r=0 depending on the way one approaches the origin. We propose a natural prescription to have rotating solutions with a minimal violation of the weak energy condition and without the questionable property of the curvature invariants at the origin.

  9. Bioreactor rotating wall vessel

    Science.gov (United States)

    2001-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.

  10. Stabilization of behaviours

    NARCIS (Netherlands)

    Geest, van der Robert

    1996-01-01

    In this paper we characterize the set of all restrictions on the behaviour of a plant that shape the characteristic polynomial of the closed-loop system. These control laws include both classical feedback laws and singular feedback laws. One of the results is the behavioural version of the Youla-Jab

  11. Rethinking retailer buying behaviour

    DEFF Research Database (Denmark)

    Esbjerg, Lars

    2001-01-01

    Research of retailer buying behaviour has previously focused on the buying decision. In this paper a new approach to studying retailer buying behaviour is suggested, one which focuses on the sensemaking processes leading up to a decision being made. A research project taking a sensemaking...

  12. Coordinate-Free Rotation Operator.

    Science.gov (United States)

    Leubner, C.

    1979-01-01

    Suggests the use of a coordinate-free rotation operator for the teaching of rotations in Euclidean three space because of its twofold didactic advantage. Illustrates the potentialities of the coordinate-free rotation operator approach by a number of examples. (Author/GA)

  13. On the Product of Rotations

    Science.gov (United States)

    Trenkler, G.; Trenkler, D.

    2008-01-01

    Using the elementary tools of matrix theory, we show that the product of two rotations in the three-dimensional Euclidean space is a rotation again. For this purpose, three types of rotation matrices are identified which are of simple structure. One of them is the identity matrix, and each of the other two types can be uniquely characterized by…

  14. Differentially Rotating White Dwarfs I: Regimes of Internal Rotation

    Science.gov (United States)

    Ghosh, Pranab; Wheeler, J. Craig

    2017-01-01

    Most viable models of Type Ia supernovae (SNe Ia) require the thermonuclear explosion of a carbon/oxygen white dwarf that has evolved in a binary system. Rotation could be an important aspect of any model for SNe Ia, whether single or double degenerate, with the white dwarf mass at, below, or above the Chandrasekhar limit. Differential rotation is specifically invoked in attempts to account for the apparent excess mass in the super-Chandrasekhar events. Some earlier work has suggested that only uniform rotation is consistent with the expected mechanisms of angular momentum transport in white dwarfs, while others have found pronounced differential rotation. We show that if the baroclinic instability is active in degenerate matter and the effects of magnetic fields are neglected, both nearly uniform rotation and strongly differential rotation are possible. We classify rotation regimes in terms of the Richardson number, Ri. At small values of Ri ≤slant 0.1, we find both the low-viscosity Zahn regime with a nonmonotonic angular velocity profile and a new differential rotation regime for which the viscosity is high and scales linearly with the shear, σ. Employment of Kelvin–Helmholtz viscosity alone yields differential rotation. Large values of Ri ≫ 1 produce a regime of nearly uniform rotation for which the baroclinic viscosity is of intermediate value and scales as {σ }3. We discuss the gap in understanding of the behavior at intermediate values of Ri and how observations may constrain the rotation regimes attained by nature.

  15. Evolution of Patterns in Rotating Bénard Convection

    Science.gov (United States)

    Fantz, M.; Friedrich, R.; Bestehorn, M.; Haken, H.

    We present an extension of the Swift-Hohenberg equation to the case of a high Prandtl number Bénard experiment in rotating fluid containers. For the case of circular containers we find complex spatio-temporal behaviour at Taylor numbers smaller than the critical one for the onset of the Küppers-Lortz instability. Furthermore, above the critical Taylor number the experimentally well-known time dependent and spatially disordered patterns in form of local patches of rolls are reproduced.

  16. Behavioural aspects of terrorism.

    Science.gov (United States)

    Leistedt, Samuel J

    2013-05-10

    Behavioural and social sciences are useful in collecting and analysing intelligence data, understanding terrorism, and developing strategies to combat terrorism. This article aims to examine the psychopathological concepts of terrorism and discusses the developing roles for behavioural scientists. A systematic review was conducted of studies investigating behavioural aspects of terrorism. These studies were identified by a systematic search of databases, textbooks, and a supplementary manual search of references. Several fundamental concepts were identified that continue to influence the motives and the majority of the behaviours of those who support or engage in this kind of specific violence. Regardless of the psychological aspects and new roles for psychiatrists, the behavioural sciences will continue to be called upon to assist in developing better methods to gather and analyse intelligence, to understand terrorism, and perhaps to stem the radicalisation process. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Rotation of cometary meteoroids

    Science.gov (United States)

    Čapek, D.

    2014-08-01

    Aims: The rotation of meteoroids caused by gas drag during the ejection from a cometary nucleus has not been studied yet. The aim of this study is to estimate the rotational characteristics of meteoroids after their release from a comet during normal activity. Methods: The basic dependence of spin rate on ejection velocity and meteoroid size is determined analytically. A sophisticated numerical model is then applied to meteoroids ejected from the 2P/Encke comet. The meteoroid shapes are approximated by polyhedrons, which have been determined by a 3D laser scanning method of 36 terrestrial rock samples. These samples come from three distinct sets with different origins and characteristics, such as surface roughness or angularity. Two types of gas-meteoroid interactions and three gas ejection models are assumed. The rotational characteristics of ejected meteoroid population are obtained by numerical integration of equations of motion with random initial conditions and random shape selection. Results: It is proved that the results do not depend on a specific set of shape models and that they are applicable to the (unknown) shapes of real meteoroids. A simple relationship between the median of meteoroid spin frequencies bar{f} (Hz), ejection velocities vej (m s-1), and sizes D (m) is determined. For diffuse reflection of gas molecules from meteoroid's surface it reads as bar{f≃ 2× 10-3 v_ej D-0.88}, and for specular reflection of gas molecules from meteoroid's surface it is bar{f≃ 5× 10-3 v_ej D-0.88}. The distribution of spin frequencies is roughly normal on log scale, and it is relatively wide: a 2σ-interval can be described as (0.1, 10)× bar{f}. Most of the meteoroids are non-principal axis rotators. The median angle between angular momentum vector and spin vector is 12°. About 60% of meteoroids rotate in long-axis mode. The distribution of angular momentum vectors is not random. They are concentrated in the perpendicular direction with respect to the gas

  18. Magnetic field effect on spoke behaviour

    Science.gov (United States)

    Hnilica, Jaroslav; Slapanska, Marta; Klein, Peter; Vasina, Petr

    2016-09-01

    The investigations of the non-reactive high power impulse magnetron sputtering (HiPIMS) discharge using high-speed camera imaging, optical emission spectroscopy and electrical probes showed that plasma is not homogeneously distributed over the target surface, but it is concentrated in regions of higher local plasma density called spokes rotating above the erosion racetrack. Magnetic field effect on spoke behaviour was studied by high-speed camera imaging in HiPIMS discharge using 3 inch titanium target. An employed camera enabled us to record two successive images in the same pulse with time delay of 3 μs between them, which allowed us to determine the number of spokes, spoke rotation velocity and spoke rotation frequency. The experimental conditions covered pressure range from 0.15 to 5 Pa, discharge current up to 350 A and magnetic fields of 37, 72 and 91 mT. Increase of the magnetic field influenced the number of spokes observed at the same pressure and at the same discharge current. Moreover, the investigation revealed different characteristic spoke shapes depending on the magnetic field strength - both diffusive and triangular shapes were observed for the same target material. The spoke rotation velocity was independent on the magnetic field strength. This research has been financially supported by the Czech Science Foundation in frame of the project 15-00863S.

  19. CISM Course on Rotating Fluids

    CERN Document Server

    1992-01-01

    The volume presents a comprehensive overview of rotation effects on fluid behavior, emphasizing non-linear processes. The subject is introduced by giving a range of examples of rotating fluids encountered in geophysics and engineering. This is then followed by a discussion of the relevant scales and parameters of rotating flow, and an introduction to geostrophic balance and vorticity concepts. There are few books on rotating fluids and this volume is, therefore, a welcome addition. It is the first volume which contains a unified view of turbulence in rotating fluids, instability and vortex dynamics. Some aspects of wave motions covered here are not found elsewhere.

  20. Counter-Rotating Accretion Discs

    OpenAIRE

    Dyda, Sergei; Lovelace, Richard V. E.; Ustyugova, Galina V.; Romanova, Marina M.; Koldoba, Alexander V.

    2014-01-01

    Counter-rotating discs can arise from the accretion of a counter-rotating gas cloud onto the surface of an existing co-rotating disc or from the counter-rotating gas moving radially inward to the outer edge of an existing disc. At the interface, the two components mix to produce gas or plasma with zero net angular momentum which tends to free-fall towards the disc center. We discuss high-resolution axisymmetric hydrodynamic simulations of a viscous counter-rotating disc for cases where the tw...

  1. Gravitational Jaynes–Cummings model beyond the rotating wave approximation

    Indian Academy of Sciences (India)

    M Mohammadi

    2012-05-01

    In this paper, the quantum properties of a two-level atom and the cavity-field in the Jaynes–Cummings model with the gravity beyond the rotating wave approximation are investigated. For this purpose, by solving the Schrödinger equation in the interaction picture, the evolving state of the system is found by which the influence of the counter-rotating terms on the dynamical behaviour of atomic population inversion and the probability distribution of the cavity-field as quantum properties is explored. The results in the atom–field system beyond the rotating wave approximation with the gravity show that the quantum properties are not completely suppressed under certain conditions.

  2. Translational and rotational dynamic analysis of a superconducting levitation system

    Science.gov (United States)

    Cansiz, A.; Hull, J. R.; Gundogdu, Ö.

    2005-07-01

    The rotational dynamics of a disc-shaped permanent magnet rotor levitated over a high temperature superconductor was studied experimentally and theoretically. The interaction between the rotor magnet and the superconductor was modelled by assuming the magnet to be a magnetic dipole and the superconductor a diamagnet. In the magnetomechanical analysis of the superconductor part, the frozen image concept was combined with the diamagnetic image, and the damping in the system was neglected. The interaction potential of the system is the combination of magnetic and gravitational potentials. From the dynamical analysis the equations of motion of the permanent magnet were stated as a function of lateral, vertical, tilt, precision and rotating angles. The vibration behaviour and correlation of the vibration of one direction with that of another were determined with a numerical calculation based on the Runge-Kutta method. The various vibrational frequencies identified were vertical, radial, tilt, precession and rotation. The tests performed for experimental verifications were translational and rotational. The permanent magnet was 'spun up' under vacuum conditions to analyse the dynamics of the free 'spin down' behaviour of the permanent magnet.

  3. Rotating electrical machines

    CERN Document Server

    Le Doeuff, René

    2013-01-01

    In this book a general matrix-based approach to modeling electrical machines is promulgated. The model uses instantaneous quantities for key variables and enables the user to easily take into account associations between rotating machines and static converters (such as in variable speed drives).   General equations of electromechanical energy conversion are established early in the treatment of the topic and then applied to synchronous, induction and DC machines. The primary characteristics of these machines are established for steady state behavior as well as for variable speed scenarios. I

  4. Optical fiber rotation sensing

    CERN Document Server

    Burns, William K; Kelley, Paul

    1993-01-01

    Optical Fiber Rotation Sensing is the first book devoted to Interferometric Fiber Optic Gyros (IFOG). This book provides a complete overview of IFOGs, beginning with a historical review of IFOG development and including a fundamental exposition of basic principles, a discussion of devices and components, and concluding with industry reports on state-of-the-art activity. With several chapters contributed by principal developers of this solid-state device, the result is an authoritative work which will serve as the resource for researchers, students, and users of IFOGs.* * State-of-t

  5. Graphs as rotations

    CERN Document Server

    Zeps, Dainis

    2009-01-01

    Using a notation of corner between edges when graph has a fixed rotation, i.e. cyclical order of edges around vertices, we define combinatorial objects - combinatorial maps as pairs of permutations, one for vertices and one for faces. Further, we define multiplication of these objects, that coincides with the multiplication of permutations. We consider closed under multiplication classes of combinatorial maps that consist of closed classes of combinatorial maps with fixed edges where each such class is defined by a knot. One class among them is special, containing selfconjugate maps.

  6. Changing Information Retrieval Behaviours

    DEFF Research Database (Denmark)

    Constantiou, Ioanna D.; Lehrer, Christiane; Hess, Thomas

    2014-01-01

    The introduction of smartphones and the accompanying profusion of mobile data services have had a profound effect on individuals' lives. One of the most influential service categories is location-based services (LBS). Based on insights from behavioural decision-making, a conceptual framework is d...... on the continuance of LBS use and indicate changes in individuals' information retrieval behaviours in everyday life. In particular, the distinct value dimension of LBS in specific contexts of use changes individuals' behaviours towards accessing location-related information....

  7. Experimental Studies of Flow Patterns of Different Fluids in a Partially Filled Rotating Cylinder

    Directory of Open Access Journals (Sweden)

    P.R. Mukunda

    2009-01-01

    Full Text Available An attempt has been made to investigate the various parameters affecting the fluid behaviour, partially filled in a rotating cylinder. When the cylinder is rotating at ‘high’ speed, a liquid forms a hollow cylinder. Different patterns are observed in the fluids for the rotatioal speeds below a critical speed. This study should give us some insight into molten metal behaviour during centrifugal casting. An extensive experimental investigation is required to obtain an appropriate functional relationship by knowing and understanding some dimensionless parameters. Here the effect of dimensionless parameters ε (which is 2 g/ω2d, where g, ω and d denotes gravitational acceleration, container rotation rate and inner diameter of liquid cylinder and G (number of times the gravity was studied as variation of rotation speed, viscosity and aspect ratio of the mould.

  8. Orthotropic rotation-free thin shell elements

    CERN Document Server

    Munglani, Gautam; Wittel, Falk K; Herrmann, Hans J

    2015-01-01

    A method to simulate orthotropic behaviour in thin shell finite elements is proposed. The approach is based on the transformation of shape function derivatives, resulting in a new orthogonal basis aligned to a specified preferred direction for all elements. This transformation is carried out solely in the undeformed state leaving minimal additional impact on the computational effort expended to simulate orthotropic materials compared to isotropic, resulting in a straightforward and highly efficient implementation. This method is implemented for rotation-free triangular shells using the finite element framework built on the Kirchhoff--Love theory employing subdivision surfaces. The accuracy of this approach is demonstrated using the deformation of a pinched hemispherical shell (with a 18{\\deg} hole) standard benchmark. To showcase the efficiency of this implementation, the wrinkling of orthotropic sheets under shear displacement is analyzed. It is found that orthotropic subdivision shells are able to capture t...

  9. Soft initial-rotation and HΦ robust constant rotational speed control for rotational MEMS gyro

    Institute of Scientific and Technical Information of China (English)

    Ma Gaoyin; Chen Wenyuan; Cui Feng; Zhang Weiping; Wang Liqi

    2009-01-01

    A novel soft initial-rotation control system and an Hoo robust constant rotational speed controller (RCRSC) for a rotational MEMS (micro-electro-mechanical system) gyro are presented. The soft initial-rotation control system can prevent the possible tumbling down of the suspended rotor and ensure a smooth and fast initial-rotation process. After the initial-rotation process, in order to maintain the rotational speed accurately constant, the RCRSC is acquired through the mixed sensitivity design approach. Simulation results show that the actuation voltage disturbances from the internal carrier waves in the gyro is reduced by more than 15.3 dB, and the speed fluctuations due to typical external vibrations ranging from 10 Hz to 200 Hz can also be restricted to 10-3 rad/s order.

  10. Rotating Wheel Wake

    Science.gov (United States)

    Lombard, Jean-Eloi; Xu, Hui; Moxey, Dave; Sherwin, Spencer

    2016-11-01

    For open wheel race-cars, such as Formula One, or IndyCar, the wheels are responsible for 40 % of the total drag. For road cars, drag associated to the wheels and under-carriage can represent 20 - 60 % of total drag at highway cruise speeds. Experimental observations have reported two, three or more pairs of counter rotating vortices, the relative strength of which still remains an open question. The near wake of an unsteady rotating wheel. The numerical investigation by means of direct numerical simulation at ReD =400-1000 is presented here to further the understanding of bifurcations the flow undergoes as the Reynolds number is increased. Direct numerical simulation is performed using Nektar++, the results of which are compared to those of Pirozzoli et al. (2012). Both proper orthogonal decomposition and dynamic mode decomposition, as well as spectral analysis are leveraged to gain unprecedented insight into the bifurcations and subsequent topological differences of the wake as the Reynolds number is increased.

  11. Rotating regular black holes

    CERN Document Server

    Bambi, Cosimo

    2013-01-01

    The formation of spacetime singularities is a quite common phenomenon in General Relativity and it is regulated by specific theorems. It is widely believed that spacetime singularities do not exist in Nature, but that they represent a limitation of the classical theory. While we do not yet have any solid theory of quantum gravity, toy models of black hole solutions without singularities have been proposed. So far, there are only non-rotating regular black holes in the literature. These metrics can be hardly tested by astrophysical observations, as the black hole spin plays a fundamental role in any astrophysical process. In this letter, we apply the Newman-Janis algorithm to the Hayward and to the Bardeen black hole metrics. In both cases, we obtain a family of rotating solutions. Every solution corresponds to a different matter configuration. Each family has one solution with special properties, which can be written in Kerr-like form in Boyer-Lindquist coordinates. These special solutions are of Petrov type ...

  12. Rotating black hole hair

    CERN Document Server

    Gregory, Ruth; Wills, Danielle

    2013-01-01

    A Kerr black hole sporting cosmic string hair is studied in the context of the abelian Higgs model vortex. It is shown that a such a system displays much richer phenomenology than its static Schwarzschild or Reissner--Nordstrom cousins, for example, the rotation generates a near horizon `electric' field. In the case of an extremal rotating black hole, two phases of the Higgs hair are possible: Large black holes exhibit standard hair, with the vortex piercing the event horizon. Small black holes on the other hand, exhibit a flux-expelled solution, with the gauge and scalar field remaining identically in their false vacuum state on the event horizon. This solution however is extremely sensitive to confirm numerically, and we conjecture that it is unstable due to a supperradiant mechanism similar to the Kerr-adS instability. Finally, we compute the gravitational back reaction of the vortex, which turns out to be far more nuanced than a simple conical deficit. While the string produces a conical effect, it is con...

  13. Optical rotation sensors

    Science.gov (United States)

    Rotge, J. R.; Simmons, B. J.; Kroncke, G. T.; Stech, D. J.

    1986-05-01

    Research efforts were concentrated on passive ring laser rotation sensor technology. Initial efforts were performed on supportive projects, e.g., laser stabilization, followed by a 0.62 sq m passive resonant ring laser gyro (PRRLG), leading to the development of a 60 sq m system mounted on the pneumatically supported isolation test platform (Iso-Pad) at FJSRL. Numerous sub-system tasks and a feasibility 0.62 sq m PRRLG were completed, supporting projections of very high resolution performance by a large 60 sq m PRRLG. The expected performance of the large PRRLG, on the order of 10 to the minus 10th power ERU (earth rate units), would provide an accurate error model applicable to Air Force operational ring laser gyros, a new source of geophysical data, e.g., earth wobble and variations in earth rotation, a proven design concept applicable to Air Force sensor needs as reference to MX instruments tests, and relativity experiments. This report documents the many accomplishments leading to, and the status of the large PRRLG at the date of the PRRLG stop order, November 1985.

  14. Rotation of Giant Stars

    CERN Document Server

    Kissin, Yevgeni

    2015-01-01

    The internal rotation of post-main sequence stars is investigated, in response to the convective pumping of angular momentum toward the stellar core, combined with a tight magnetic coupling between core and envelope. The spin evolution is calculated using model stars of initial mass 1, 1.5 and $5\\,M_\\odot$, taking into account mass loss on the giant branches and the partitioning of angular momentum between the outer and inner envelope. We also include the deposition of orbital angular momentum from a sub-stellar companion, as influenced by tidal drag as well as the excitation of orbital eccentricity by a fluctuating gravitational quadrupole moment. A range of angular velocity profiles $\\Omega(r)$ is considered in the deep convective envelope, ranging from solid rotation to constant specific angular momentum. We focus on the backreaction of the Coriolis force on the inward pumping of angular momentum, and the threshold for dynamo action in the inner envelope. Quantitative agreement with measurements of core ro...

  15. Rotational Spectrum of Saccharine

    Science.gov (United States)

    Alonso, Elena R.; Mata, Santiago; Alonso, José L.

    2017-06-01

    A significant step forward in the structure-activity relationships of sweeteners was the assignment of the AH-B moiety in sweeteners by Shallenberger and Acree. They proposed that all sweeteners contain an AH-B moiety, known as glucophore, in which A and B are electronegative atoms separated by a distance between 2.5 to 4 Å. H is a hydrogen atom attached to one of the electronegative atom by a covalent bond. For saccharine, one of the oldest artificial sweeteners widely used in food and drinks, two possible B moieties exist ,the carbonyl oxygen atom and the sulfoxide oxygen atom although there is a consensus of opinion among scientists over the assignment of AH-B moieties to HN-SO. In the present work, the solid of saccharine (m.p. 220°C) has been vaporized by laser ablation (LA) and its rotational spectrum has been analyzed by broadband CP-FTMW and narrowband MB-FTMW Fourier transform microwave techniques. The detailed structural information extracted from the rotational constants and ^{14}N nuclear quadrupole coupling constants provided enough information to ascribe the glucophore's AH and B sites of saccharine. R. S. Shallenberger, T. E. Acree. Nature 216, 480-482 Nov 1967. R. S. Shallenberger. Taste Chemistry; Blackie Academic & Professional, London, (1993).

  16. Pure Nano-Rotation Scanner

    Directory of Open Access Journals (Sweden)

    Moo-Yeon Lee

    2012-01-01

    Full Text Available We developed and tested a novel rotation scanner for nano resolution and accurate rotary motion about the rotation center. The scanner consists of circular hinges and leaf springs so that the parasitic error at the center of the scanner in the X and Y directions is minimized, and rotation performance is optimized. Each sector of the scanner's system was devised to have nano resolution by minimizing the parasitic errors of the rotation center that arise due to displacements other than rotation. The analytic optimal design results of the proposed scanner were verified using finite element analyses. The piezoelectric actuators were used to attain nano-resolution performances, and a capacitive sensor was used to measure displacement. A feedback controller was used to minimize the rotation errors in the rotation scanner system under practical conditions. Finally, the performance evaluation test results showed that the resonance frequency was 542 Hz, the resolution was 0.09 μrad, and the rotation displacement was 497.2 μrad. Our test results revealed that the rotation scanner exhibited accurate rotation about the center of the scanner and had good nano precision.

  17. Psychology: Inducing green behaviour

    Science.gov (United States)

    Thøgersen, John

    2013-02-01

    Economic arguments, such as saving money, are often used to promote pro-environmental actions -- for example, reducing energy use. However, research shows that people's environmental motives are sometimes better drivers of behavioural change.

  18. Energy efficiency and behaviour

    DEFF Research Database (Denmark)

    Carstensen, Trine Agervig; Kunnasvirta, Annika; Kiviluoto, Katariina

    The purpose of Work Package 5 Deliverable 5.1., “Case study reports on energy efficiency and behaviour” is to present examples of behavioral interventions to promote energy efficiency in cities. The case studies were collected in January – June 2014, and they represent behavioural interventions...... factors. The main addressees of D5.1. are city officials, NGO representatives, private sector actors and any other relevant actors who plan and realize behavioural energy efficiency interventions in European cities. The WP5 team will also further apply results from D5.1. with a more general model on how...... to conduct behavioural interventions, to be presented in Deliverable 5.5., the final report. This report will also provide valuable information for the WP6 general model for an Energy-Smart City. Altogether 38 behavioural interventions are analysed in this report. Each collected and analysed case study...

  19. Relaxing Behavioural Inheritance

    Directory of Open Access Journals (Sweden)

    Nuno Amálio

    2013-05-01

    Full Text Available Object-oriented (OO inheritance allows the definition of families of classes in a hierarchical way. In behavioural inheritance, a strong version, it should be possible to substitute an object of a subclass for an object of its superclass without any observable effect on the system. Behavioural inheritance is related to formal refinement, but, as observed in the literature, the refinement constraints are too restrictive, ruling out many useful OO subclassings. This paper studies behavioural inheritance in the context of ZOO, an object-oriented style for Z. To overcome refinement's restrictions, this paper proposes relaxations to the behavioural inheritance refinement rules. The work is presented for Z, but the results are applicable to any OO language that supports design-by-contract.

  20. Gender and Behaviour

    African Journals Online (AJOL)

    ... to articles, that reflect psychological and behavioural aspects of gender in general. ... Is entrepreneurial orientation a predictor of entrepreneurial activity? ... Personality traits and sexual satisfaction as determinants of marital satisfaction ...

  1. Energy Conservation Behaviour Toolkit

    NARCIS (Netherlands)

    Kalz, Marco; Börner, Dirk; Ternier, Stefaan; Specht, Marcus

    2013-01-01

    Kalz, M., Börner, D., Ternier, S., & Specht, M. (2013, 31 January). Energy Conservation Behaviour Toolkit. Presentation given at the symposium "Groene ICT en Duurzame ontwikkeling: Meters maken in het Hoger Onderwijs", Driebergen, The Netherlands.

  2. Recycling as moral behaviour

    DEFF Research Database (Denmark)

    Thøgersen, John

    of Reasoned Action (TRA) with regard to understanding recycling behaviour. Further, examples of misleading policy conclusions are discussed suggested that within the framework of cognitive psychology, Schwartz's model of altruistic behaviour offers a more satisfying starting point for understanding recycling......It is argued in this paper that in the affluent, industrial societies, environmental behaviours like recycling are typically classified within ""the domain of morality"" in people's minds. Intentions regarding these types of behaviours are not ba a thorough - conscious or unconscious - calculation...... of the balance of costs and benefits. Rather, they are a function of the person's moral beliefs, i.e., beliefs in what is the right or wrong thing to do. The paper gives a brief review of the literature with the intention of uncovering problems and shortcomings in the framework of the SEU-model and the Theory...

  3. Energy efficiency and behaviour

    DEFF Research Database (Denmark)

    Carstensen, Trine Agervig; Kunnasvirta, Annika; Kiviluoto, Katariina

    factors. The main addressees of D5.1. are city officials, NGO representatives, private sector actors and any other relevant actors who plan and realize behavioural energy efficiency interventions in European cities. The WP5 team will also further apply results from D5.1. with a more general model on how...... to conduct behavioural interventions, to be presented in Deliverable 5.5., the final report. This report will also provide valuable information for the WP6 general model for an Energy-Smart City. Altogether 38 behavioural interventions are analysed in this report. Each collected and analysed case study......The purpose of Work Package 5 Deliverable 5.1., “Case study reports on energy efficiency and behaviour” is to present examples of behavioral interventions to promote energy efficiency in cities. The case studies were collected in January – June 2014, and they represent behavioural interventions...

  4. Bifurcations of rotating waves in rotating spherical shell convection.

    Science.gov (United States)

    Feudel, F; Tuckerman, L S; Gellert, M; Seehafer, N

    2015-11-01

    The dynamics and bifurcations of convective waves in rotating and buoyancy-driven spherical Rayleigh-Bénard convection are investigated numerically. The solution branches that arise as rotating waves (RWs) are traced by means of path-following methods, by varying the Rayleigh number as a control parameter for different rotation rates. The dependence of the azimuthal drift frequency of the RWs on the Ekman and Rayleigh numbers is determined and discussed. The influence of the rotation rate on the generation and stability of secondary branches is demonstrated. Multistability is typical in the parameter range considered.

  5. Visualizing rotations and composition of rotations with the Rodrigues vector

    Science.gov (United States)

    Valdenebro, Angel G.

    2016-11-01

    The purpose of this paper is to show that the mathematical treatment of three-dimensional rotations can be simplified, and its geometrical understanding improved, using the Rodrigues vector representation. We present a novel geometrical interpretation of the Rodrigues vector. Based on this interpretation and simple geometrical considerations, we derive the Euler-Rodrigues formula, Cayley’s rotation formula and the composition law for finite rotations. The level of this discussion should be suitable for undergraduate physics or engineering courses where rotations are discussed.

  6. Wave behaviour and noncomplementary particle behaviour in the same experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rangwala, Sadiq (Tata Institute of Fundamental Research, Bombay 400 005 (India)); Roy, S.M. (Tata Institute of Fundamental Research, Bombay 400 005 (India))

    1994-07-11

    Grangier, Roger and Aspect have recently performed beautiful experiments, which show that the same single photon source shows wave behaviour or particle behaviour depending on the experimental arrangement. We propose experiments in which quantum mechanics predicts wave behaviour and noncomplementary particle behaviour in the same experiment. ((orig.))

  7. Wave behaviour and noncomplementary particle behaviour in the same experiment

    Science.gov (United States)

    Rangwala, Sadiq; Roy, S. M.

    1994-07-01

    Grangier, Roger and Aspect have recently performed beautiful experiments, which show that the same single photon source shows wave behaviour or particle behaviour depending on the experimental arrangement. We propose experiments in which quantum mechanics predicts wave behaviour and noncomplementary particle behaviour in the same experiment.

  8. Velocity dependant splash behaviour

    Science.gov (United States)

    Hamlett, C. A. E.; Shirtcliffe, N. J.; McHale, G.; Ahn, S.; Doerr, S. H.; Bryant, R.; Newton, M. I.

    2012-04-01

    Extreme soil water repellency can occur in nature via condensation of volatile organic compounds released during wildfires and can lead to increased erosion rate. Such extreme water repellent soil can be classified as superhydrophobic and shares similar chemical and topographical features to specifically designed superhydrophobic surfaces. Previous studies using high speed videography to investigate single droplet impact behaviour on artificial superhydrophobic have revealed three distinct modes of splash behaviour (rebound, pinned and fragmentation) which are dependent on the impact velocity of the droplet. In our studies, using high-speed videography, we show that such splash behaviour can be replicated on fixed 'model' water repellent soils (hydrophobic glass beads/particles). We show that the type of splash behaviour is dependent on both the size and chemical nature of the fixed particles. The particle shape also influences the splash behaviour as shown by drop impact experiments on fixed sand samples. We have also studied soil samples, as collected from the field, which shows that the type of droplet splash behaviour can lead to enhanced soil particle transport.

  9. Triaxial rotation in atomic nuclei

    Institute of Scientific and Technical Information of China (English)

    CHEN Yong-Shou; GAO Zao-Chun

    2009-01-01

    The Projected Shell Model has been developed to include the spontaneously broken axial symmetry so that the rapidly rotating triaxial nuclei can be described microscopically. The theory provides an useful tool to gain an insight into how a triaxial nucleus rotates, a fundamental question in nuclear structure. We shall address some current interests that are strongly associated with the triaxial rotation. A feasible method to explore the problem has been suggested.

  10. Rotations, quaternions, and double groups

    CERN Document Server

    Altmann, Simon L

    2005-01-01

    This self-contained text presents a consistent description of the geometric and quaternionic treatment of rotation operators, employing methods that lead to a rigorous formulation and offering complete solutions to many illustrative problems.Geared toward upper-level undergraduates and graduate students, the book begins with chapters covering the fundamentals of symmetries, matrices, and groups, and it presents a primer on rotations and rotation matrices. Subsequent chapters explore rotations and angular momentum, tensor bases, the bilinear transformation, projective representations, and the g

  11. Electronic Control Of Slow Rotations

    Science.gov (United States)

    Howard, David E.; Smith, Dennis A.

    1992-01-01

    Digital/analog circuit controls both angular position and speed of rotation of motor shaft with high precision. Locks angular position of motor to phase of rotation-command clock signal at binary submultiple of master clock signal. Circuit or modified version used to control precisely position and velocity of robotic manipulator, to control translation mechanism of crystal-growing furnace, to position hands of mechanical clock, or to control angular position and rate of rotation in any of large variety of rotating mechanisms.

  12. The Rapidly Rotating Sun

    Science.gov (United States)

    Hanasoge, Shravan M.; Duvall, Thomas L., Jr.; Sreenivasan, Katepalli R.

    2012-01-01

    Convection in the solar interior is thought to comprise structures at a continuum of scales, from large to small. This conclusion emerges from phenomenological studies and numerical simulations though neither covers the proper range of dynamical parameters of solar convection. In the present work, imaging techniques of time-distance helioseismology applied to observational data reveal no long-range order in the convective motion. We conservatively bound the associated velocity magnitudes, as a function of depth and the spherical-harmonic degree l to be 20-100 times weaker than prevailing estimates within the wavenumber band l ux of a solar luminosity outwards? The Sun is seemingly a much faster rotator than previously thought, with advection dominated by Coriolis forces at scales l < 60.

  13. PLT rotating pumped limiter

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, S.A.; Budny, R.V.; Corso, V.; Boychuck, J.; Grisham, L.; Heifetz, D.; Hosea, J.; Luyber, S.; Loprest, P.; Manos, D.

    1984-07-01

    A limiter with a specially contoured front face and the ability to rotate during tokamak discharges has been installed in a PLT pump duct. These features have been selected to handle the unique particle removal and heat load requirements of ICRF heating and lower-hybrid current-drive experiments. The limiter has been conditioned and commissioned in an ion-beam test stand by irradiation with 1 MW power, 200 ms duration beams of 40 keV hydrogen ions. Operation in PLT during ohmic discharges has proven the ability of the limiter to reduce localized heating caused by energetic electron bombardment and to remove about 2% of the ions lost to the PLT walls and limiters.

  14. Rotational Baroclinic Adjustment

    DEFF Research Database (Denmark)

    Holtegård Nielsen, Steen Morten

    In stratified waters like those around Denmark there is a close correlation between the biology of the water masses and their structure and currents; this is known as dynamic biologicaloceanography. The currents are particularly strong near the fronts, which can be seen in several places throughout...... the reciprocal of the socalled Coriolis parameter, and the length scale, which is known as the Rossby radius. Also, because of their limited width currents influenced by rotation are quite persistent. The flow which results from the introduction of a surface level discontinuity across a wide channel is discussed...... of the numerical model a mechanism for the generation of along-frontal instabilities and eddies is suggested. Also, the effect of an irregular bathymetry is studied.Together with observations of wind and water levels some of the oceanographical observations from the old lightvessels are used to study...

  15. Sporcularda rotator cuff problemleri

    OpenAIRE

    Guven, Osman; Guven, Zeynep; Gundes, Hakan; Yalcin, Selim

    2004-01-01

    Rotator cuff tendinitinin etyolojisinde genellikle birden çok faktörün kombinasyonu görülür. Yüzme, raket sporları ve fırlatma sporlarının özellikle gelişmiş ülkelerde giderek yaygınlaşması bu konuya olan ilginin artmasına sebep olmuştur. Eski konseptlerde aktif bir sporcuda tedavinin başarısı genellikle eski atletik seviyesine dönmesi ile ölçülürdü. Son zamanlarda atletik tekniklerin analizi, atroskopik evaluasyon gibi yeni bir Iükse sahip olmamız ve Iiteratürün yeniden gözden geçirilmesi il...

  16. Information behaviour: models and concepts

    Directory of Open Access Journals (Sweden)

    Polona Vilar

    2005-01-01

    Full Text Available The article presents an overview of the research area of information behaviour. Information behaviour is defined as the behaviour of individuals in relation to information sources and channels, which results as a consequence of their information need, and encompasses passive and active searching of information, and its use. Theoretical foundations are presented, as well as some fundamental conceptual models of information behaviour and related concepts: information searching behaviour, which occurrs in active, purposeful searching for information, regardless of the information source used; and information seeking behaviour, which represents a micro-level of information searching behaviour, and is expressed by those individuals who interact with information retrieval systems.

  17. Modeling rigid magnetically rotated microswimmers: rotation axes, bistability, and controllability.

    Science.gov (United States)

    Meshkati, Farshad; Fu, Henry Chien

    2014-12-01

    Magnetically actuated microswimmers have recently attracted attention due to many possible biomedical applications. In this study we investigate the dynamics of rigid magnetically rotated microswimmers with permanent magnetic dipoles. Our approach uses a boundary element method to calculate a mobility matrix, accurate for arbitrary geometries, which is then used to identify the steady periodically rotating orbits in a co-rotating body-fixed frame. We evaluate the stability of each of these orbits. We map the magnetoviscous behavior as a function of dimensionless Mason number and as a function of the angle that the magnetic field makes with its rotation axis. We describe the wobbling motion of these swimmers by investigating how the rotation axis changes as a function of experimental parameters. We show that for a given magnetic field strength and rotation frequency, swimmers can have more than one stable periodic orbit with different rotation axes. Finally, we demonstrate that one can improve the controllability of these types of microswimmers by adjusting the relative angle between the magnetic field and its axis of rotation.

  18. Regimes of Internal Rotation in Differentially Rotating White Dwarfs

    Science.gov (United States)

    Wheeler, J. Craig; Ghosh, Pranab

    2017-01-01

    Most viable models of Type Ia supernovae (SN Ia) require the thermonuclear explosion of a carbon/oxygen white dwarf that has evolved in a binary system. Rotation could be an important aspect of any model for SN Ia, whether single or double degenerate, with the white dwarf mass at, below, or above the Chandrasekhar limit. Differential rotation is specifically invoked in attempts to account for the apparent excess mass in the super--Chandrasekhar events. Some earlier work has suggested that only uniform rotation is consistent with the expected mechanisms of angular momentum transport in white dwarfs, while others have found pronounced differential rotation. We show that if the baroclinic instability is active in degenerate matter and the effects of magnetic fields are neglected, both nearly-uniform and strongly-differential rotation are possible. We classify rotation regimes in terms of the Richardson number, Ri. At small values of Ri > 1 produce a regime of nearly-uniform rotation for which the baroclinic viscosity is of intermediate value and scales as σ3. We discuss the gap in understanding of the behavior at intermediate values of Ri and how observations may constrain the rotation regimes attained by nature.

  19. Unidirectional Rotation of Molecules Measured by the Rotational Doppler Effect

    Directory of Open Access Journals (Sweden)

    Prior Yehiam

    2013-03-01

    Full Text Available A pair of linearly polarized pump pulses induce field-free unidirectional molecular rotation, which is detected by a delayed circularly polarized probe. The polarization and spectrum of the probe are modified by the interaction with the molecules, in accordance with the Rotational Doppler Effect.

  20. Predicting superdeformed rotational band-head spin in A ∼ 190 mass region using variable moment of inertia model

    Indian Academy of Sciences (India)

    V S Uma; Alpana Goel; Archana Yadav; A K Jain

    2016-01-01

    The band-head spin (0) of superdeformed (SD) rotational bands in ∼ 190 mass region is predicted using the variable moment of inertia (VMI) model for 66 SD rotational bands. The superdeformed rotational bands exhibited considerably good rotational property and rigid behaviour. The transition energies were dependent on the prescribed band-head spins. The ratio of transition energies over spin /2 (RTEOS) vs. angular momentum ( ) have confirmed the rigid behaviour, provided the band-head spin value is assigned correctly. There is a good agreement between the calculated and the observed transition energies. This method gives a very comprehensive interpretation for spin assignment of SD rotational bands which could help in designing future experiments for SD bands.

  1. Communication and abnormal behaviour.

    Science.gov (United States)

    Crown, S

    1979-01-01

    In this paper the similarities between normal and abnormal behaviour are emphasized and selected aspects of communication, normal and aberrant, between persons are explored. Communication in a social system may be verbal or non-verbal: one person's actions cause a response in another person. This response may be cognitive, behavioural or physiological. Communication may be approached through the individual, the social situation or social interaction. Psychoanalysis approaches the individual in terms of the coded communications of psychoneurotic symptoms or psychotic behaviour; the humanist-existential approach is concerned more with emotional expression. Both approaches emphasize the development of individual identity. The interaction between persons and their social background is stressed. Relevant are sociological concepts such as illness behaviour, stigma, labelling, institutionalization and compliance. Two approaches to social interactions are considered: the gamesplaying metaphor, e.g. back pain as a psychosocial manipulation--the 'pain game'; and the 'spiral of reciprocal perspectives' which emphasizes the interactional complexities of social perceptions. Communicatory aspects of psychological treatments are noted: learning a particular metaphor such as 'resolution' of the problem (psychotherapy), learning more 'rewarding' behaviour (learning theory) or learning authenticity or self-actualization (humanist-existential).

  2. Quasilocal rotating conformal Killing horizons

    CERN Document Server

    Chatterjee, Ayan

    2015-01-01

    The formulation of quasi-local conformal Killling horizons(CKH) is extended to include rotation. This necessitates that the horizon be foliated by 2-spheres which may be distorted. Matter degrees of freedom which fall through the horizon is taken to be a real scalar field. We show that these rotating CKHs also admit a first law in differential form.

  3. Rotation of the planet mercury.

    Science.gov (United States)

    Jefferys, W H

    1966-04-08

    The equations of motion for the rotation of Mercury are solved for the general case by an asymptotic expansion. The findings of Liu and O'Keefe, obtained by numerical integration of a special case, that it is possible for Mercury's rotation to be locked into a 2:3 resonance with its revolution, are confirmed in detail. The general solution has further applications.

  4. KEPLER RAPIDLY ROTATING GIANT STARS

    Energy Technology Data Exchange (ETDEWEB)

    Costa, A. D.; Martins, B. L. Canto; Bravo, J. P.; Paz-Chinchón, F.; Chagas, M. L. das; Leão, I. C.; Oliveira, G. Pereira de; Silva, R. Rodrigues da; Roque, S.; Oliveira, L. L. A. de; Silva, D. Freire da; De Medeiros, J. R., E-mail: renan@dfte.ufrn.br [Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal RN (Brazil)

    2015-07-10

    Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of substellar companions by their hosting stars. In the present Letter, we report 17 giant stars observed in the scope of the Kepler space mission exhibiting rapid rotation behavior. For the first time, the abnormal rotational behavior for this puzzling family of stars is revealed by direct measurements of rotation, namely from photometric rotation period, exhibiting a very short rotation period with values ranging from 13 to 55 days. This finding points to remarkable surface rotation rates, up to 18 times the rotation of the Sun. These giants are combined with six others recently listed in the literature for mid-infrared (IR) diagnostics based on Wide-field Infrared Survey Explorer information, from which a trend for an IR excess is revealed for at least one-half of the stars, but at a level far lower than the dust excess emission shown by planet-bearing main-sequence stars.

  5. Kepler rapidly rotating giant stars

    CERN Document Server

    Costa, A D; Bravo, J P; Paz-Chinchón, F; Chagas, M L das; Leão, I C; de Oliveira, G Pereira; da Silva, R Rodrigues; Roque, S; de Oliveira, L L A; da Silva, D Freire; De Medeiros, J R

    2015-01-01

    Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of sub-stellar companions by their hosting stars. In the present letter we report 17 giant stars observed in the scope of the Kepler space mission exhibiting rapid rotation behavior. For the first time the abnormal rotational behavior for this puzzling family of stars is revealed by direct measurements of rotation, namely from photometric rotation period, exhibiting very short rotation period with values ranging from 13 to 55 days. This finding points for remarkable surface rotation rates, up to 18 times the Sun rotation. These giants are combined with 6 other recently listed in the literature for mid-IR diagnostic based on WISE information, from which a trend for an infrared excess is revealed for at least a half of the stars, but at a level far lower than the dust excess emission shown by planet-bearing main-sequence stars.

  6. Occupants' window opening behaviour

    DEFF Research Database (Denmark)

    Fabi, Valentina; Andersen, Rune Korsholm; Corgnati, Stefano

    2012-01-01

    Energy consumption in buildings is influenced by several factors related to the building properties and the building controls, some of them highly connected to the behaviour of their occupants.In this paper, a definition of items referring to occupant behaviour related to the building control...... systems is proposed, based on studies presented in literature and a general process leading to the effects on energy consumptions is identified.Existing studies on the topic of window opening behaviour are highlighted and a theoretical framework to deal with occupants' interactions with building controls......, aimed at improving or maintaining the preferred indoor environmental conditions, is elaborated. This approach is used to look into the drivers for the actions taken by the occupants (windows opening and closing) and to investigate the existing models in literature of these actions for both residential...

  7. Changing physician prescribing behaviour.

    Science.gov (United States)

    Gray, J

    2006-01-01

    Didactic approaches to educating physicians and/or other health professionals do not produce changes in learner behaviour. Similarly, printed materials and practice guidelines have not been shown to change prescribing behaviour. Evidence-based educational approaches that do have an impact on provider behaviour include: teaching aimed at identified learning needs; interactive educational activities; sequenced and multifaceted interventions; enabling tools such as patient education programs, flow charts, and reminders; educational outreach or academic detailing; and audit and feedback to prescribers. Dr. Jean Gray reflects over the past 25 years on how there has been a transformation in the types of activities employed to improve prescribing practices in Nova Scotia. The evolution of Continuing Medical Education (CME) has resulted in the creation of the Drug Evaluation Alliance of Nova Scotia (DEANS) program, which is one exemplar of an evidence-based educational approach to improving physician prescribing in that province. Key words: Evidence-based, education, prescribing.

  8. The radiative zone of the Sun and the tachocline: stability of baroclinic patterns of differential rotation

    CERN Document Server

    Caleo, Andrea

    2016-01-01

    Barotropic rotation and radiative equilibrium are mutually incompatible in stars. The issue is often addressed by allowing for a meridional circulation, but this is not devoid of theoretical complications. Models of rotation in the Sun which maintain strict radiative equilibrium, making use of the observation that the Sun is not in a state of barotropic rotation, have recently been suggested. To investigate the dynamical behaviour of these solutions, we study the local stability of stratified, weakly magnetized, differentially rotating fluids to non-axisymmetric perturbations. Finite heat conductivity, kinematic viscosity, and resistivity are present. The evolution of local embedded perturbations is governed by a set of coupled, ordinary differential equations with time-dependent coefficients. Two baroclinic models of rotation for the upper radiative zone and tachocline are studied: (i) an interpolation based on helioseismology data, (ii) a theoretical solution directly compatible with radiative equilibrium. ...

  9. Slowly rotating homogeneous masses revisited

    CERN Document Server

    Reina, Borja

    2015-01-01

    Hartle's model for slowly rotating stars has been extensively used to compute equilibrium configurations of slowly rotating stars to second order in perturbation theory in General Relativity, given a barotropic equation of state (EOS). A recent study based on the modern theory of perturbed matchings show that the model must be amended to accommodate EOS's in which the energy density does not vanish at the surface of the non rotating star. In particular, the expression for the change in mass given in the original model, i.e. a contribution to the mass that arises when the perturbations are chosen so that the pressure of the rotating and non rotating configurations agree, must be modified with an additional term. In this paper, the amended change in mass is calculated for the case of constant density stars.

  10. Bidirectional optical rotation of cells

    Directory of Open Access Journals (Sweden)

    Jiyi Wu

    2017-08-01

    Full Text Available Precise and controlled rotation manipulation of cells is extremely important in biological applications and biomedical studies. Particularly, bidirectional rotation manipulation of a single or multiple cells is a challenge for cell tomography and analysis. In this paper, we report an optical method that is capable of bidirectional rotation manipulation of a single or multiple cells. By launching a laser beam at 980 nm into dual-beam tapered fibers, a single or multiple cells in solutions can be trapped and rotated bidirectionally under the action of optical forces. Moreover, the rotational behavior can be controlled by altering the relative distance between the two fibers and the input optical power. Experimental results were interpreted by numerical simulations.

  11. Bidirectional optical rotation of cells

    Science.gov (United States)

    Wu, Jiyi; Zhang, Weina; Li, Juan

    2017-08-01

    Precise and controlled rotation manipulation of cells is extremely important in biological applications and biomedical studies. Particularly, bidirectional rotation manipulation of a single or multiple cells is a challenge for cell tomography and analysis. In this paper, we report an optical method that is capable of bidirectional rotation manipulation of a single or multiple cells. By launching a laser beam at 980 nm into dual-beam tapered fibers, a single or multiple cells in solutions can be trapped and rotated bidirectionally under the action of optical forces. Moreover, the rotational behavior can be controlled by altering the relative distance between the two fibers and the input optical power. Experimental results were interpreted by numerical simulations.

  12. Optomechanics for absolute rotation detection

    Science.gov (United States)

    Davuluri, Sankar

    2016-07-01

    In this article, we present an application of optomechanical cavity for the absolute rotation detection. The optomechanical cavity is arranged in a Michelson interferometer in such a way that the classical centrifugal force due to rotation changes the length of the optomechanical cavity. The change in the cavity length induces a shift in the frequency of the cavity mode. The phase shift corresponding to the frequency shift in the cavity mode is measured at the interferometer output to estimate the angular velocity of absolute rotation. We derived an analytic expression to estimate the minimum detectable rotation rate in our scheme for a given optomechanical cavity. Temperature dependence of the rotation detection sensitivity is studied.

  13. Advances in Rotational Seismic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, Robert [Applied Technology Associates, Albuquerque, NM (United States); Laughlin, Darren [Applied Technology Associates, Albuquerque, NM (United States); Brune, Robert [Applied Technology Associates, Albuquerque, NM (United States)

    2016-10-19

    Rotational motion is increasingly understood to be a significant part of seismic wave motion. Rotations can be important in earthquake strong motion and in Induced Seismicity Monitoring. Rotational seismic data can also enable shear selectivity and improve wavefield sampling for vertical geophones in 3D surveys, among other applications. However, sensor technology has been a limiting factor to date. The US Department of Energy (DOE) and Applied Technology Associates (ATA) are funding a multi-year project that is now entering Phase 2 to develop and deploy a new generation of rotational sensors for validation of rotational seismic applications. Initial focus is on induced seismicity monitoring, particularly for Enhanced Geothermal Systems (EGS) with fracturing. The sensors employ Magnetohydrodynamic (MHD) principles with broadband response, improved noise floors, robustness, and repeatability. This paper presents a summary of Phase 1 results and Phase 2 status.

  14. Information behaviour and practice

    CERN Document Server

    Rafferty, Pauline; Baker, David

    2015-01-01

    This special issue explores information behaviour and practice in general, and specifically focuses on the implications for library and information services. Information seeking behaviour and information practice remain areas of importance in information science and librarianship, perhaps even more so in the digital age. This special issue is an opportunity to share ideas and scholarship and to explore models and methods. The papers chosen for inclusion cover a range of topics and approach them from a number of different epistemological and methodological positions demonstrating the liveliness

  15. Rotational evolution of slow-rotators sequence stars

    CERN Document Server

    Lanzafame, Alessandro C

    2015-01-01

    The observed mass-age-rotation relationship in open clusters shows the progressive development of a slow-rotators sequence at masses lower than 1.2 $M_{\\odot}$. After 0.6 Gyr, almost all stars have settled on this sequence. The observed clustering on this sequence suggests that it corresponds to some equilibrium or asymptotic condition that still lacks a complete theoretical interpretation, crucial to our understanding of the stellar angular momentum evolution. We couple a rotational evolution model that takes into account internal differential rotation with classical and new proposals for the wind braking law, and fit models to the data using a Monte Carlo Markov Chain method tailored to the case at hand. We explore the extent to which these models are able to reproduce the mass and time dependence of the stellar rotational evolution on the slow-rotators sequence. The description of the early evolution (0.1-0.6 Gyr) of the slow-rotators sequence requires taking into account the transfer of angular momentum f...

  16. Magnetostrophic Rotating Magnetoconvection

    Science.gov (United States)

    King, Eric; Aurnou, Jonathan

    2016-11-01

    Planetary magnetic fields are generated by turbulent convection within their vast interior liquid metal cores. Although direct observation is not possible, this liquid metal circulation is thought to be dominated by the controlling influences of Coriolis and Lorentz forces. Theory famously predicts that local-scale convection naturally settles into the so-called magnetostrophic state, where the Coriolis and Lorentz forces partially cancel, and convection is optimally efficient. To date, no laboratory experiments have reached the magnetostrophic regime in turbulent liquid metal convection. Furthermore, computational dynamo simulations have as yet failed to produce a globally magnetostrophic dynamo, which has led some to question the existence of the magnetostrophic state. Here, we present results from the first turbulent magnetostrophic rotating magnetoconvection experiments using the liquid metal gallium. We find that turbulent convection in the magnetostrophic regime is, in fact, maximally efficient. The experimental results clarify these previously disparate results, suggesting that the fluid dynamics saturate in magnetostrophic balance within turbulent liquid metal, planetary cores. The authors thank the NSF Geophysics Program for financial support.

  17. Behaviour Centred Design: towards an applied science of behaviour change

    Science.gov (United States)

    Aunger, Robert; Curtis, Valerie

    2016-01-01

    ABSTRACT Behaviour change has become a hot topic. We describe a new approach, Behaviour Centred Design (BCD), which encompasses a theory of change, a suite of behavioural determinants and a programme design process. The theory of change is generic, assuming that successful interventions must create a cascade of effects via environments, through brains, to behaviour and hence to the desired impact, such as improved health. Changes in behaviour are viewed as the consequence of a reinforcement learning process involving the targeting of evolved motives and changes to behaviour settings, and are produced by three types of behavioural control mechanism (automatic, motivated and executive). The implications are that interventions must create surprise, revalue behaviour and disrupt performance in target behaviour settings. We then describe a sequence of five steps required to design an intervention to change specific behaviours: Assess, Build, Create, Deliver and Evaluate. The BCD approach has been shown to change hygiene, nutrition and exercise-related behaviours and has the advantages of being applicable to product, service or institutional design, as well as being able to incorporate future developments in behaviour science. We therefore argue that BCD can become the foundation for an applied science of behaviour change. PMID:27535821

  18. Perceptual strategies of pigeons to detect a rotational centre--a hint for star compass learning?

    Directory of Open Access Journals (Sweden)

    Bianca Alert

    Full Text Available Birds can rely on a variety of cues for orientation during migration and homing. Celestial rotation provides the key information for the development of a functioning star and/or sun compass. This celestial compass seems to be the primary reference for calibrating the other orientation systems including the magnetic compass. Thus, detection of the celestial rotational axis is crucial for bird orientation. Here, we use operant conditioning to demonstrate that homing pigeons can principally learn to detect a rotational centre in a rotating dot pattern and we examine their behavioural response strategies in a series of experiments. Initially, most pigeons applied a strategy based on local stimulus information such as movement characteristics of single dots. One pigeon seemed to immediately ignore eccentric stationary dots. After special training, all pigeons could shift their attention to more global cues, which implies that pigeons can learn the concept of a rotational axis. In our experiments, the ability to precisely locate the rotational centre was strongly dependent on the rotational velocity of the dot pattern and it crashed at velocities that were still much faster than natural celestial rotation. We therefore suggest that the axis of the very slow, natural, celestial rotation could be perceived by birds through the movement itself, but that a time-delayed pattern comparison should also be considered as a very likely alternative strategy.

  19. Perceptual strategies of pigeons to detect a rotational centre--a hint for star compass learning?

    Science.gov (United States)

    Alert, Bianca; Michalik, Andreas; Helduser, Sascha; Mouritsen, Henrik; Güntürkün, Onur

    2015-01-01

    Birds can rely on a variety of cues for orientation during migration and homing. Celestial rotation provides the key information for the development of a functioning star and/or sun compass. This celestial compass seems to be the primary reference for calibrating the other orientation systems including the magnetic compass. Thus, detection of the celestial rotational axis is crucial for bird orientation. Here, we use operant conditioning to demonstrate that homing pigeons can principally learn to detect a rotational centre in a rotating dot pattern and we examine their behavioural response strategies in a series of experiments. Initially, most pigeons applied a strategy based on local stimulus information such as movement characteristics of single dots. One pigeon seemed to immediately ignore eccentric stationary dots. After special training, all pigeons could shift their attention to more global cues, which implies that pigeons can learn the concept of a rotational axis. In our experiments, the ability to precisely locate the rotational centre was strongly dependent on the rotational velocity of the dot pattern and it crashed at velocities that were still much faster than natural celestial rotation. We therefore suggest that the axis of the very slow, natural, celestial rotation could be perceived by birds through the movement itself, but that a time-delayed pattern comparison should also be considered as a very likely alternative strategy.

  20. Pyrolysis of cassava rhizome in a counter-rotating twin screw reactor unit.

    Science.gov (United States)

    Sirijanusorn, Somsak; Sriprateep, Keartisak; Pattiya, Adisak

    2013-07-01

    A counter-rotating twin screw reactor unit was investigated for its behaviour in the pyrolysis of cassava rhizome biomass. Several parameters such as pyrolysis temperature in the range of 500-700°C, biomass particle size of twin screw reactor was relatively low, whereas the solids content was relatively high, compared to some other reactor configurations.

  1. Behavioural Finance: Theory and Survey

    Directory of Open Access Journals (Sweden)

    Daiva Jurevičienė

    2013-04-01

    Full Text Available The paper analyses the importance of behavioural finance theories in household decision-making process. Behavioural finance theories investigate emotional characteristics to explain subjective factors and irrational anomalies in financial markets. In this regard, behavioural theories and behavioural anomalies in the decision-making process are examined; the application opportunities in the financial market are described. The aim of investigation is to determine the basic features and slopes of behavioural finance in concordance with financial decisions of a household. The survey method was applied to ascertain financial behaviour of literate households.

  2. Behavioural Real Estate

    NARCIS (Netherlands)

    D. Salzman (Diego); R.C.J. Zwinkels (Remco)

    2013-01-01

    textabstractThe behavioural approach to decision making under uncertainty combines insights from psychology and sociology into economic decision making. It steps away from the normative homo economicus and introduces a positive approach to human decision making under uncertainty. We provide an overv

  3. Gender and Behaviour: Submissions

    African Journals Online (AJOL)

    Gender and Behaviour Ife Centre for Psychological Studies and Service. ... On page 1, type article title, author name(s), affiliation(s) address phone and fax ... the manuscript includes only original materials test has not been published and that ...

  4. Resilient behaviour of soils

    OpenAIRE

    Correia, A. Gomes; Gilett, S.

    1996-01-01

    This study examine the resilient behaviour of sands, silts and clay for different moisture conditions and various stress paths. The analysis of data from repeated load triaxial tests carried out on these recompacted soils has enable to test different models and validate their hability to predict resilient response of soils.

  5. Measuring innovative work behaviour

    NARCIS (Netherlands)

    de Jong, J.; den Hartog, D.

    2010-01-01

    Both scientists and practitioners emphasize the importance of innovative work behaviour (IWB) of individual employees for organizational success, but the measurement of IWB is still at an evolutionary stage. This article is concerned with developed a measure of IWB with four potential dimensions: th

  6. Managing Behaviour in Classrooms

    Institute of Scientific and Technical Information of China (English)

    邹柯

    2008-01-01

    Managing the class is a fussy but indispensable job for the class teacher. The relationship between teachers and students is a subtle one, which is different with each group. So it is a duty to manage their behaviour, meanwhile the teachers'skills of management appears more important.

  7. Sexual risk taking behaviour

    DEFF Research Database (Denmark)

    Buttmann, Nina; Nielsen, Ann; Munk, Christian

    2011-01-01

    Sexual habits and risky sexual behaviour strongly affect public health. Available data indicate that sexually transmitted infections are increasing in many EU countries. Changes in the epidemiology of sexually transmitted diseases across Europe are among other factors suggested to be driven by ch...

  8. Measuring innovative work behaviour

    NARCIS (Netherlands)

    de Jong, J.; den Hartog, D.

    2010-01-01

    Both scientists and practitioners emphasize the importance of innovative work behaviour (IWB) of individual employees for organizational success, but the measurement of IWB is still at an evolutionary stage. This article is concerned with developed a measure of IWB with four potential dimensions:

  9. Observing behaviour categorically

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Cheng, Allan

    1995-01-01

    In an attempt to understand the relationships and differences between the extensive amount of research within the field of bisimulation equivalences, Joyal, Nielsen, and Winskel recently proposed an abstract category-theoretic definition of bisimulation. They identify spans of morphisms satisfyin......, in fact, captures not only bisimulations but many other behavioural equivalences. We also briefly present presheaf models as an abstract model of computation....

  10. Observing behaviour categorically

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Cheng, Allan

    1995-01-01

    In an attempt to understand the relationships and differences between the extensive amount of research within the field of bisimulation equivalences, Joyal, Nielsen, and Winskel recently proposed an abstract category-theoretic definition of bisimulation. They identify spans of morphisms satisfyin......, in fact, captures not only bisimulations but many other behavioural equivalences. We also briefly present presheaf models as an abstract model of computation....

  11. One-Dimensional Modelling of Marine Current Turbine Runaway Behaviour

    Directory of Open Access Journals (Sweden)

    Staffan Lundin

    2016-04-01

    Full Text Available If a turbine loses its electrical load, it will rotate freely and increase speed, eventually achieving that rotational speed which produces zero net torque. This is known as a runaway situation. Unlike many other types of turbine, a marine current turbine will typically overshoot the final runaway speed before slowing down and settling at the runaway speed. Since the hydrodynamic forces acting on the turbine are dependent on rotational speed and acceleration, turbine behaviour during runaway becomes important for load analyses during turbine design. In this article, we consider analytical and numerical models of marine current turbine runaway behaviour in one dimension. The analytical model is found not to capture the overshoot phenomenon, while still providing useful estimates of acceleration at the onset of runaway. The numerical model incorporates turbine wake build-up and predicts a rotational speed overshoot. The predictions of the models are compared against measurements of runaway of a marine current turbine. The models are also used to recreate previously-published results for a tidal turbine and applied to a wind turbine. It is found that both models provide reasonable estimates of maximum accelerations. The numerical model is found to capture the speed overshoot well.

  12. On regular rotating black holes

    Science.gov (United States)

    Torres, R.; Fayos, F.

    2017-01-01

    Different proposals for regular rotating black hole spacetimes have appeared recently in the literature. However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking. In this note we analyze rotating Kerr-like black hole spacetimes and find the necessary and sufficient conditions for the regularity of all their second order scalar invariants polynomial in the Riemann tensor. We also show that the regularity is linked to a violation of the weak energy conditions around the core of the rotating black hole.

  13. On regular rotating black holes

    CERN Document Server

    Torres, Ramon

    2016-01-01

    Different proposals for regular rotating black hole spacetimes have appeared recently in the literature. However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking. In this note we analyze rotating Kerr-like black hole spacetimes and find the necessary and sufficient conditions for the regularity of all their second order scalar invariants polynomial in the Riemann tensor. We also show that the regularity is linked to a violation of the weak energy conditions around the core of the rotating black hole.

  14. Cooling system for rotating machine

    Science.gov (United States)

    Gerstler, William Dwight; El-Refaie, Ayman Mohamed Fawzi; Lokhandwalla, Murtuza; Alexander, James Pellegrino; Quirion, Owen Scott; Palafox, Pepe; Shen, Xiaochun; Salasoo, Lembit

    2011-08-09

    An electrical machine comprising a rotor is presented. The electrical machine includes the rotor disposed on a rotatable shaft and defining a plurality of radial protrusions extending from the shaft up to a periphery of the rotor. The radial protrusions having cavities define a fluid path. A stationary shaft is disposed concentrically within the rotatable shaft wherein an annular space is formed between the stationary and rotatable shaft. A plurality of magnetic segments is disposed on the radial protrusions and the fluid path from within the stationary shaft into the annular space and extending through the cavities within the radial protrusions.

  15. Motor processes in mental rotation

    OpenAIRE

    Wexler, Mark; Kosslyn, Stephen; Berthoz, Alain

    1997-01-01

    Much indirect evidence supports the hypothesis that transformations of mental images are at least in part guided by motor processes, even in the case of images of abstract objects rather than of body parts. For example, rotation may be guided by processes that also prime one to see results of a specific motor action. We directly test the hypothesis by means of a dual-task paradigm in which subjects perform the Cooper-Shepard mental rotation task while executing an unseen motor rotation in a g...

  16. Rotational spectra and molecular structure

    CERN Document Server

    Wollrab, James E

    1967-01-01

    Physical Chemistry, A Series of Monographs: Rotational Spectra and Molecular Structure covers the energy levels and rotational transitions. This book is divided into nine chapters that evaluate the rigid asymmetric top molecules and the nuclear spin statistics for asymmetric tops. Some of the topics covered in the book are the asymmetric rotor functions; rotational transition intensities; classes of molecules; nuclear spin statistics for linear molecules and symmetric tops; and classical appearance of centrifugal and coriolis forces. Other chapters deal with the energy levels and effects of ce

  17. Rotated and Scaled Alamouti Coding

    CERN Document Server

    Willems, Frans M J

    2008-01-01

    Repetition-based retransmission is used in Alamouti-modulation [1998] for $2\\times 2$ MIMO systems. We propose to use instead of ordinary repetition so-called "scaled repetition" together with rotation. It is shown that the rotated and scaled Alamouti code has a hard-decision performance which is only slightly worse than that of the Golden code [2005], the best known $2\\times 2$ space-time code. Decoding the Golden code requires an exhaustive search over all codewords, while our rotated and scaled Alamouti code can be decoded with an acceptable complexity however.

  18. Study on wall recycling behaviour in CPD spherical tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyay, R. [Interdisciplinary Graduate School of Engineering Science, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan)], E-mail: raju@triam.kyushu-u.ac.jp; Zushi, H. [Research Institute of Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Hirooka, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan); Sakamoto, M. [Research Institute of Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Yoshinaga, T. [National Institute for Fusion Science, Toki 509-5292 (Japan); Okamoto, K. [Interdisciplinary Graduate School of Engineering Science, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Kawasaki, S.; Hanada, K.; Sato, K.N.; Nakamura, K.; Idei, H. [Research Institute of Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Ryoukai, T. [Interdisciplinary Graduate School of Engineering Science, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Nakashima, H.; Higashijima, A. [Research Institute of Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan)

    2008-12-15

    Experiments to study wall recycling behaviour have been performed in the small spherical tokamak compact plasma-wall interaction experimental device (CPD) from the viewpoint of global as well as local plasma wall interaction condition. Electron cyclotron resonance (ECR) plasma of typically {approx}50 to 400 ms duration is produced using {approx}40 to 80 kW RF power. In order to study the global wall recycling behaviour, pressure measurements are carried out just before and after the ECR plasma in the absence of any external pumping. The recycling behaviour is found to change from release to pumping beyond a certain level of pressure value which is again found to be a function of shot history. The real-time local wall behaviour is studied in similar RF plasma using a rotating tungsten limiter, actively coated with lithium. Measurement of H{sub {alpha}} light intensity in front of the rotating surface has indicated a clear reduction ({approx}10%) in the steady-state hydrogen recycling with continuous Li gettering of several minutes.

  19. Differentially Rotating White Dwarfs I: Regimes of Internal Rotation

    CERN Document Server

    Ghosh, Pranab

    2016-01-01

    Most viable models of Type Ia supernovae (SN~Ia) require the thermonuclear explosion of a carbon/oxygen white dwarf that has evolved in a binary system. Rotation could be an important aspect of any model for SN~Ia, whether single or double degenerate, with the white dwarf mass at, below, or above the Chandrasekhar limit. {\\sl Differential rotation} is specifically invoked in attempts to account for the apparent excess mass in the super--Chandrasekhar events. Some earlier work has suggested that only uniform rotation is consistent with the expected mechanisms of angular momentum transport in white dwarfs, while others have found pronounced differential rotation. We show that if the baroclinic instability is active in degenerate matter and the effects of magnetic fields are neglected, both nearly-uniform and strongly-differential rotation are possible. We classify rotation regimes in terms of the Richardson number, Ri. At small values of Ri $\\leq$ 0.1, we find both the low-viscosity Zahn regime with a non-monot...

  20. A numerical strategy for modelling rotating stall in core compressors

    Science.gov (United States)

    Vahdati, M.

    2007-03-01

    conditions downstream. Such an approach is representative of modelling an engine.Using a 3D viscous time-accurate flow representation, the front bladerows of a core compressor were modelled in a whole-annulus fashion whereas the rest of bladerows are modelled in a single-passage fashion. The rotating stall behaviour at two different compressor operating points was studied by considering two different variable-vane scheduling conditions for which experimental data were available. Using a model with nine whole-assembly models, the unsteady-flow calculations were conducted on 32-CPUs of a parallel cluster, typical run times being around 3-4 weeks for a grid with about 60 million points. The simulations were conducted over several engine rotations. As observed on the actual development engine, there was no rotating stall for the first scheduling condition while mal-scheduling of the stator vanes created a 12-band rotating stall which excited the 1st flap mode.

  1. FOSTERING ADOLESCENTS' INTERPERSONAL BEHAVIOUR: AN ...

    African Journals Online (AJOL)

    Engr E. Egbochukwu

    Training, Interpersonal Behaviour, Emotions and Gender. Introduction ... stress and lessen the risk of later emotional and behavioural problems. ... relationships, which create knowledge and develop intelligence, which in turn, gives meaning ...

  2. Neuroendocrine control of maternal behaviour

    OpenAIRE

    Caughey, Sarah Dawn

    2011-01-01

    Maternal behaviour during the peri-partum period, albeit in differing forms, can be observed in all mammals, thus it must serve an important evolutionary purpose in enabling the successful raising of offspring. Maternal behaviour is comprised of a large suite of behaviours; in rodents these are generally defined as lactation, pup retrieval, maternal aggression and pup grooming. The maternal behaviour circuitry involves many brain regions including the hypothalamus and the limbi...

  3. Rotational ratchets with dipolar interactions.

    Science.gov (United States)

    Jäger, Sebastian; Klapp, Sabine H L

    2012-12-01

    We report results from a computer simulation study on the rotational ratchet effect in systems of magnetic particles interacting via dipolar interactions. The ratchet effect consists of directed rotations of the particles in an oscillating magnetic field, which lacks a net rotating component. Our investigations are based on Brownian dynamics simulations of such many-particle systems. We investigate the influence of both the random and deterministic contributions to the equations of motion on the ratchet effect. As a main result, we show that dipolar interactions can have an enhancing as well as a dampening effect on the ratchet behavior depending on the dipolar coupling strength of the system under consideration. The enhancement is shown to be caused by an increase in the effective field on a particle generated by neighboring magnetic particles, while the dampening is due to restricted rotational motion in the effective field. Moreover, we find a nontrivial influence of the short-range, repulsive interaction between the particles.

  4. The rotation of brown dwarfs

    CERN Document Server

    Scholz, Aleks

    2016-01-01

    One of the characteristic features of low-mass stars is their propensity to shed large amounts of angular momentum throughout their evolution. This distinguishs them from brown dwarfs which remain fast rotators over timescales of gigayears. Brown dwarfs with rotation periods longer than a couple of days have only been found in star forming regions and young clusters. This is a useful constraint on the mass dependency of mechanisms for angular momentum regular in stars. Rotational braking by disks and winds become highly inefficient in the substellar regime. In this short review I discuss the observational evidence for the fast rotation in brown dwarfs, the implications, and the link to the spin-mass relation in planets.

  5. Structural dynamics in rotating systems

    Science.gov (United States)

    Kiraly, Louis J.

    1993-01-01

    Major issues and recent advances in the structural dynamics of rotating systems are summarized. The objectives and benefits of such systems are briefly discussed. Directions for future research are suggested.

  6. Spontaneous Rotational Inversion in Phycomyces

    KAUST Repository

    Goriely, Alain

    2011-03-01

    The filamentary fungus Phycomyces blakesleeanus undergoes a series of remarkable transitions during aerial growth. During what is known as the stagea IV growth phase, the fungus extends while rotating in a counterclockwise manner when viewed from above (stagea IVa) and then, while continuing to grow, spontaneously reverses to a clockwise rotation (stagea IVb). This phase lasts for 24-48Ah and is sometimes followed by yet another reversal (stageAIVc) before the overall growth ends. Here, we propose a continuum mechanical model of this entire process using nonlinear, anisotropic, elasticity and show how helical anisotropy associated with the cell wall structure can induce spontaneous rotation and, under appropriate circumstances, the observed reversal of rotational handedness. © 2011 American Physical Society.

  7. Identical high- K three-quasiparticle rotational bands

    Science.gov (United States)

    Kaur, Harjeet; Singh, Pardeep

    2016-12-01

    A comprehensive study of high- K three-quasiparticle rotational bands in odd- A nuclei indicates the similarity in γ -ray energies and dynamic moment of inertia Im^{(2)} . The extent of the identicality between the rotational bands is evaluated by using the energy factor method. For nuclei pairs exhibiting identical bands, the average relative change in the dynamic moment of inertia Im^{(2)} is also determined. The identical behaviour shown by these bands is attributed to the interplay of nuclear structure parameters: deformation and the pairing correlations. Also, experimental trend of the I(hbar) vs. hbar ω (MeV) plot for these nuclei pairs is shown to be in agreement with Tilted-Axis Cranking (TAC) model calculations.

  8. The evolution of behaviour therapy and cognitive behaviour therapy.

    Science.gov (United States)

    Rachman, S

    2015-01-01

    The historical background of the development of behaviour therapy is described. It was based on the prevailing behaviourist psychology and constituted a fundamentally different approach to the causes and treatment of psychological disorders. It had a cold reception and the idea of treating the behaviour of neurotic and other patients was regarded as absurd. The opposition of the medical profession and psychoanalysts is explained. Parallel but different forms of behaviour therapy developed in the US and UK. The infusion of cognitive concepts and procedures generated a merger of behaviour therapy and cognitive therapy, cognitive behaviour therapy (CBT). The strengths and limitations of the early and current approaches are evaluated.

  9. Rotating thin-shell wormhole

    Science.gov (United States)

    Ovgun, A.

    2016-11-01

    We construct a rotating thin-shell wormhole using a Myers-Perry black hole in five dimensions, using the Darmois-Israel junction conditions. The stability of the wormhole is analyzed under perturbations. We find that exotic matter is required at the throat of the wormhole to keep it stable. Our analysis shows that stability of the rotating thin-shell wormhole is possible if suitable parameter values are chosen.

  10. Rotationally symmetric viscous gas flows

    Science.gov (United States)

    Weigant, W.; Plotnikov, P. I.

    2017-03-01

    The Dirichlet boundary value problem for the Navier-Stokes equations of a barotropic viscous compressible fluid is considered. The flow region and the data of the problem are assumed to be invariant under rotations about a fixed axis. The existence of rotationally symmetric weak solutions for all adiabatic exponents from the interval (γ*,∞) with a critical exponent γ* < 4/3 is proved.

  11. Rotating Shadowband Spectroradiometer (RSS) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Kiedron, P; Schlemmer, J; Klassen, M

    2005-01-01

    The rotating shawdowband spectroradiometer (RSS) implements the same automated shadowbanding technique used by the multifilter rotating shadowband radiometer (MFRSR), and so it too provides spectrally-resolved, direct-normal, diffuse-horizontal, and total-horizontal irradiances, and can be calibrated in situ via Langley regression. The irradiance spectra are measured simultaneously at all spectral elements (pixels) in 360-nm to 1050-nm range.

  12. Rotating Thin-Shell Wormhole

    CERN Document Server

    Ovgun, A

    2016-01-01

    In this article, we construct rotating thin shell wormhole using a Myers-Perry black hole in five dimensions. The stability of the wormhole is analyzed under perturbations follows from the Darmois-Israel junction conditions. We find that it required exotic matter at the throat to keep throat of wormhole stable. Our analysis shows that the stability of the rotating thin-shell wormhole is available with choosing suitable values of parameters.

  13. The stability of lifestyle behaviour

    NARCIS (Netherlands)

    Mulder, M; Ranchor, AV; Sanderman, R; Bouma, J; van den Heuvel, WJA

    1998-01-01

    Background The stability of Lifestyle behaviour has been studied over a 4-year period in a sample of 1400 men in The Netherlands. The influence of both socioeconomic status and age was studied in relation to lifestyle behaviour change. Methods Lifestyle behaviour was analysed by means of index score

  14. Lopsidedness in WHISP galaxies: I. Rotation curves and kinematic lopsidedness

    CERN Document Server

    van Eymeren, J; Jog, C J; Stein, Y; Dettmar, R -J

    2011-01-01

    The frequently observed lopsidedness of the distribution of stars and gas in disc galaxies is still considered as a major problem in galaxy dynamics. It is even discussed as an imprint of the formation history of discs and the evolution of baryons in dark matter haloes. Here, we analyse a selected sample of 70 galaxies from the Westerbork HI Survey of Spiral and Irregular Galaxies. The HI data allow us to follow the morphology and the kinematics out to very large radii. In the present paper, we present the rotation curves and study the kinematic asymmetry. We extract the rotation curves of receding and approaching sides separately and show that the kinematic behaviour of disc galaxies can be classified by five different types: symmetric velocity fields where the rotation curves of receding and approaching sides are almost identical; global distortions where the rotation velocities of receding and approaching side have an offset which is constant with radius; local distortions which lead to large deviations in...

  15. The behavioural ecology of irrational behaviours.

    Science.gov (United States)

    Huneman, Philippe; Martens, Johannes

    2017-08-17

    Natural selection is often envisaged as the ultimate cause of the apparent rationality exhibited by organisms in their specific habitat. Given the equivalence between selection and rationality as maximizing processes, one would indeed expect organisms to implement rational decision-makers. Yet, many violations of the clauses of rationality have been witnessed in various species such as starlings, hummingbirds, amoebas and honeybees. This paper attempts to interpret such discrepancies between economic rationality (defined by the main axioms of rational choice theory) and biological rationality (defined by natural selection). After having distinguished two kinds of rationality we introduce irrationality as a negation of economic rationality by biologically rational decision-makers. Focusing mainly on those instances of irrationalities that can be understood as exhibiting inconsistency in making choices, i.e. as non-conformity of a given behaviour to axioms such as transitivity or independence of irrelevant alternatives, we propose two possible families of Darwinian explanations that may account for these apparent irrationalities. First, we consider cases where natural selection may have been an indirect cause of irrationality. Second, we consider putative cases where violations of rationality axioms may have been directly favored by natural selection. Though the latter cases (prima facie) seem to clearly contradict our intuitive representation of natural selection as a process that maximizes fitness, we argue that they are actually unproblematic; for often, they can be redescribed as cases where no rationality axiom is violated, or as situations where no adaptive solution exists in the first place.

  16. Jupiter and Saturn Rotation Periods

    CERN Document Server

    Helled, Ravit; Anderson, John D

    2009-01-01

    Anderson & Schubert (2007, Science,317,1384) proposed that Saturn's rotation period can be ascertained by minimizing the dynamic heights of the 100 mbar isosurface with respect to the geoid; they derived a rotation period of 10h 32m 35s. We investigate the same approach for Jupiter to see if the Jovian rotation period is predicted by minimizing the dynamical heights of its isobaric (1 bar pressure level) surface using zonal wind data. A rotation period of 9h 54m 29s is found. Further, we investigate the minimization method by fitting Pioneer and Voyager occultation radii for both Jupiter and Saturn. Rotation periods of 9h 55m 30s and 10h 32m 35s are found to minimize the dynamical heights for Jupiter and Saturn, respectively. Though there is no dynamical principle requiring the minimization of the dynamical heights of an isobaric surface, the successful application of the method to Jupiter lends support to its relevance for Saturn. We derive Jupiter and Saturn rotation periods using equilibrium theory in ...

  17. Counter-Rotating Accretion Discs

    CERN Document Server

    Dyda, Sergei; Ustyugova, Galina V; Romanova, Marina M; Koldoba, Alexander V

    2014-01-01

    Counter-rotating discs can arise from the accretion of a counter-rotating gas cloud onto the surface of an existing co-rotating disc or from the counter-rotating gas moving radially inward to the outer edge of an existing disc. At the interface, the two components mix to produce gas or plasma with zero net angular momentum which tends to free-fall towards the disc center. We discuss high-resolution axisymmetric hydrodynamic simulations of a viscous counter-rotating disc for cases where the two components are vertically separated and radially separated. The viscosity is described by an isotropic $\\alpha-$viscosity including all terms in the viscous stress tensor. For the vertically separated components a shear layer forms between them. The middle of this layer free-falls to the disk center. The accretion rates are increased by factors $\\sim 10^2-10^4$ over that of a conventional disc rotating in one direction with the same viscosity. The vertical width of the shear layer and the accretion rate are strongly dep...

  18. The rotation of Galaxy Clusters

    CERN Document Server

    Tovmassian, Hrant M

    2015-01-01

    The method for detection of the galaxy cluster rotation based on the study of distribution of member galaxies with velocities lower and higher of the cluster mean velocity over the cluster image is proposed. The search for rotation is made for flat clusters with $a/b>1.8$ and BMI type clusters which are expected to be rotating. For comparison there were studied also round clusters and clusters of NBMI type, the second by brightness galaxy in which does not differ significantly from the cluster cD galaxy. Seventeen out of studied 65 clusters are found to be rotating. It was found that the detection rate is sufficiently high for flat clusters, over 60\\%, and clusters of BMI type with dominant cD galaxy, ~ 35%. The obtained results show that clusters were formed from the huge primordial gas clouds and preserved the rotation of the primordial clouds, unless they did not have merging with other clusters and groups of galaxies, in the result of which the rotation has been prevented.

  19. Cognitive Behavioural Therapy & Training

    DEFF Research Database (Denmark)

    Spaten, Ole Michael; Hansen, Tia G. B.; Gulbrandsen, Knut Arild

    coaching module in the graduate curriculum for students of psychology is a rewarding introduction to cognitive behavioural approaches, since it allows combination of traditional lectures with “action-reflection-learning” workshops, during which students train cognitive behavioural techniques in their own......Coaching is an expanding area of professional work, and recent years have brought forward the notion of cognitive coaching (Costa, 2006; Oestrich, 2005) which adapts theory and techniques from cognitive therapy to serve self-enhancement in non-clinical populations. We suggest that a cognitive...... repertoire. The skills needed for cognitive coaching reflect all therapeutic techniques but at a less advanced psychotherapeutic level, and still prepare for future clinical work and development. In the poster, we summarise a cognitive coaching course syllabus as well as results from data collected...

  20. Cognitive Behavioural Therapy & Training

    DEFF Research Database (Denmark)

    Spaten, Ole Michael; Hansen, Tia G. B.; Gulbrandsen, Knut Arild

    Coaching is an expanding area of professional work, and recent years have brought forward the notion of cognitive coaching (Costa, 2006; Oestrich, 2005) which adapts theory and techniques from cognitive therapy to serve self-enhancement in non-clinical populations. We suggest that a cognitive...... coaching module in the graduate curriculum for students of psychology is a rewarding introduction to cognitive behavioural approaches, since it allows combination of traditional lectures with “action-reflection-learning” workshops, during which students train cognitive behavioural techniques in their own...... repertoire. The skills needed for cognitive coaching reflect all therapeutic techniques but at a less advanced psychotherapeutic level, and still prepare for future clinical work and development. In the poster, we summarise a cognitive coaching course syllabus as well as results from data collected...

  1. Psychological Factors Influencing Consumer Behaviour

    OpenAIRE

    Vainikka, Bianca

    2015-01-01

    This paper’s aim is to provide an in-depth elucidation of the many aspects that influence consumer behaviour. The study of consumer behaviour emphasizes the “why” and “how” questions involved in decision making and buying behaviour. This exciting field visits a dynamic blend of themes of consumer marketing strategies, psychology and behavioural discipline. Consumer behaviour in this day and age is highly applicable to modern society as it is an integral part of our everyday lives. This paper ...

  2. Rotation, differential rotation, and gyrochronology of active Kepler stars

    CERN Document Server

    Reinhold, Timo

    2015-01-01

    The high-precision photometry from the CoRoT and Kepler satellites has led to measurements of surface rotation periods for tens of thousands of stars. Our main goal is to derive ages of thousands of field stars using consistent rotation period measurements in different gyrochronology relations. Multiple rotation periods are interpreted as surface differential rotation (DR). We re-analyze the sample of 24,124 Kepler stars from Reinhold et al. (2013) using different approaches based on the Lomb-Scargle periodogram. Each quarter (Q1-Q14) is treated individually using a prewhitening approach. Additionally, the full time series, and different segments thereof are analyzed. For more than 18,500 stars our results are consistent with the rotation periods from McQuillan et al. (2014). Thereof, more than 12,300 stars show multiple significant peaks, which we interpret as DR. Gyrochronology ages between 100 Myr and 10 Gyr were derived for more than 17,000 stars using different gyrochronology relations. We find a bimodal...

  3. Predicting People's Environmental Behaviour: Theory of Planned Behaviour and Model of Responsible Environmental Behaviour

    Science.gov (United States)

    Chao, Yu-Long

    2012-01-01

    Using different measures of self-reported and other-reported environmental behaviour (EB), two important theoretical models explaining EB--Hines, Hungerford and Tomera's model of responsible environmental behaviour (REB) and Ajzen's theory of planned behaviour (TPB)--were compared regarding the fit between model and data, predictive ability,…

  4. Predicting People's Environmental Behaviour: Theory of Planned Behaviour and Model of Responsible Environmental Behaviour

    Science.gov (United States)

    Chao, Yu-Long

    2012-01-01

    Using different measures of self-reported and other-reported environmental behaviour (EB), two important theoretical models explaining EB--Hines, Hungerford and Tomera's model of responsible environmental behaviour (REB) and Ajzen's theory of planned behaviour (TPB)--were compared regarding the fit between model and data, predictive ability,…

  5. Rehabilitation after Rotator Cuff Repair.

    Science.gov (United States)

    Nikolaidou, Ourania; Migkou, Stefania; Karampalis, Christos

    2017-01-01

    Rotator cuff tears are a very common condition that is often incapacitating. Whether non-surgical or surgical, successful management of rotator cuff disease is dependent on appropriate rehabilitation. If conservative management is insufficient, surgical repair is often indicated. Postsurgical outcomes for patients having had rotator cuff repair can be quite good. A successful outcome is much dependent on surgical technique as it is on rehabilitation. Numerous rehabilitation protocols for the management of rotator cuff disease are based primarily on clinical experience and expert opinion. This article describes the different rehabilitation protocols that aim to protect the repair in the immediate postoperative period, minimize postoperative stiffness and muscle atrophy. A review of currently available literature on rehabilitation after arthroscopic rotator cuff tear repair was performed to illustrate the available evidence behind various postoperative treatment modalities. There were no statistically significant differences between a conservative and an accelerated rehabilitation protocol . Early passive range of motion (ROM) following arthroscopic cuff repair is thought to decrease postoperative stiffness and improve functionality. However, early aggressive rehabilitation may compromise repair integrity. The currently available literature did not identify any significant differences in functional outcomes and relative risks of re-tears between delayed and early motion in patients undergoing arthroscopic rotator cuff repairs. A gentle rehabilitation protocol with limits in range of motion and exercise times after arthroscopic rotator cuff repair would be better for tendon healing without taking any substantial risks. A close communication between the surgeon, the patient and the physical therapy team is important and should continue throughout the whole recovery process.

  6. Rotation terrestre et Variations du champ de gravité : Etude et apport des missions CHAMP et GRACE

    OpenAIRE

    Bourda, G.

    2004-01-01

    Michel Kasser (Président du jury; IGN, France) Véronique Dehant (Rapporteur; Observatoire royal de Belgique) Markus Rothacher (Rappporteur; IERS, Allemagne) Harald Shuh (Examinateur; Université de Vienne, Autriche); The masses distributions inside the Earth govern the Earth rotation rate, as well as the behaviour of the rotation axis in the Earth and in space. These distributions of masses can be measured by space owing to artificial satellites, the orbitography of which provides the Earth gr...

  7. Counter-Rotation in Disk Galaxies

    CERN Document Server

    Corsini, E M

    2014-01-01

    Counter-rotating galaxies host two components rotating in opposite directions with respect to each other. The kinematic and morphological properties of lenticulars and spirals hosting counter-rotating components are reviewed. Statistics of the counter-rotating galaxies and analysis of their stellar populations provide constraints on the formation scenarios which include both environmental and internal processes.

  8. Transitions in turbulent rotating convection

    Science.gov (United States)

    Rajaei, Hadi; Alards, Kim; Kunnen, Rudie; Toschi, Federico; Clercx, Herman; Fluid Dynamics Lab Team

    2015-11-01

    This study aims to explore the flow transition from one state to the other in rotating Rayleigh-Bènard convection using Lagrangian acceleration statistics. 3D particle tracking velocimetry (3D-PTV) is employed in a water-filled cylindrical tank of equal height and diameter. The measurements are performed at the center and close to the top plate at a Rayleigh number Ra = 1.28e9 and Prandtl number Pr = 6.7 for different rotation rates. In parallel, direct numerical simulation (DNS) has been performed to provide detailed information on the boundary layers. We report the acceleration pdfs for different rotation rates and show how the transition from weakly to strongly rotating Rayleigh-Bènard affects the acceleration pdfs in the bulk and boundary layers. We observe that the shapes of the acceleration PDFs as well as the isotropy in the cell center are largely unaffected while crossing the transition point. However, acceleration pdfs at the top show a clear change at the transition point. Using acceleration pdfs and DNS data, we show that the transition between turbulent states is actually a boundary layer transition between Prandtl-Blasius type (typical of non-rotating convection) and Ekman type.

  9. Rapidly rotating neutron star progenitors

    Science.gov (United States)

    Postnov, K. A.; Kuranov, A. G.; Kolesnikov, D. A.; Popov, S. B.; Porayko, N. K.

    2016-12-01

    Rotating proto-neutron stars can be important sources of gravitational waves to be searched for by present-day and future interferometric detectors. It was demonstrated by Imshennik that in extreme cases the rapid rotation of a collapsing stellar core may lead to fission and formation of a binary proto-neutron star which subsequently merges due to gravitational wave emission. In this paper, we show that such dynamically unstable collapsing stellar cores may be the product of a former merger process of two stellar cores in a common envelope. We applied population synthesis calculations to assess the expected fraction of such rapidly rotating stellar cores which may lead to fission and formation of a pair of proto-neutron stars. We have used the BSE (Binary Star Evolution) population synthesis code supplemented with a new treatment of stellar core rotation during the evolution via effective core-envelope coupling, characterized by the coupling time, τc. The validity of this approach is checked by direct MESA calculations of the evolution of a rotating 15 M⊙ star. From comparison of the calculated spin distribution of young neutron stars with the observed one, reported by Popov and Turolla, we infer the value τc ≃ 5 × 105 yr. We show that merging of stellar cores in common envelopes can lead to collapses with dynamically unstable proto-neutron stars, with their formation rate being ˜0.1-1 per cent of the total core collapses, depending on the common envelope efficiency.

  10. Rapidly rotating neutron star progenitors

    Science.gov (United States)

    Postnov, K. A.; Kuranov, A. G.; Kolesnikov, D. A.; Popov, S. B.; Porayko, N. K.

    2016-08-01

    Rotating proto-neutron stars can be important sources of gravitational waves to be searched for by present-day and future interferometric detectors. It was demonstrated by Imshennik that in extreme cases the rapid rotation of a collapsing stellar core may lead to fission and formation of a binary proto-neutron star which subsequently merges due to gravitational wave emission. In the present paper, we show that such dynamically unstable collapsing stellar cores may be the product of a former merger process of two stellar cores in a common envelope. We applied population synthesis calculations to assess the expected fraction of such rapidly rotating stellar cores which may lead to fission and formation of a pair of proto-neutron stars. We have used the BSE population synthesis code supplemented with a new treatment of stellar core rotation during the evolution via effective core-envelope coupling, characterized by the coupling time, τc. The validity of this approach is checked by direct MESA calculations of the evolution of a rotating 15 M⊙ star. From comparison of the calculated spin distribution of young neutron stars with the observed one, reported by Popov and Turolla, we infer the value τc ≃ 5 × 105 years. We show that merging of stellar cores in common envelopes can lead to collapses with dynamically unstable proto-neutron stars, with their formation rate being ˜0.1 - 1% of the total core collapses, depending on the common envelope efficiency.

  11. Rotational spectroscopy of interstellar PAHs

    CERN Document Server

    Ali-Haïmoud, Yacine

    2013-01-01

    Polycyclic aromatic hydrocarbons (PAHs) have long been part of the standard model of the interstellar medium, and are believed to play important roles in its physics and chemistry. Yet, up to now it has not been possible to identify any specific molecule among them. In this paper, a new observational avenue is suggested to detect individual PAHs, using their rotational line emission at radio frequencies. Previous PAH searches based on rotational spectroscopy have only targeted the bowl-shaped corannulene molecule, with the underlying assumption that other polar PAHs are triaxial and as a consequence their rotational emission is diluted over a very large number of lines and unusable for detection purposes. In this paper the rotational spectrum of quasi-symmetric PAHs is computed analytically, as a function of the level of triaxiality. It is shown that the asymmetry of planar, nitrogen-substituted symmetric PAHs is small enough that their rotational spectrum, when observed with a resolution of about a MHz, has ...

  12. Bifurcation analysis of the behavior of partially wetting liquids on a rotating cylinder

    CERN Document Server

    Lin, Te-Sheng; Tseluiko, Dmitri; Thiele, Uwe

    2015-01-01

    We discuss the behavior of partially wetting liquids on a rotating cylinder using the model of Thiele [J. Fluid Mech. 671, 121-136 (2011)] that takes into account the effects of gravity, viscosity, rotation, surface tension and wettability. Such a system can be considered as a prototype for many other systems where the interplay of spatial heterogeneity and a lateral driving force in the proximity of a first- or second-order phase transition results in intricate behaviour. So does a partially wetting drop on a rotating cylinder undergo a depinning transition as the rotation speed is increased, whereas for ideally wetting liquids the behavior changes monotonically. We analyze in detail the transition in the bifurcation behavior for partially wetting liquids as the wettability of the liquid decreases, and, in particular, how the global bifurcation related to the depinning of drops is created when increasing the contact angle. We employ various numerical continuation techniques that allow us to track stable/unst...

  13. The rotational anisotropies in the ferromagnetism/antiferromagnetism 1/antiferromagnetism 2 exchange bias structures

    Institute of Scientific and Technical Information of China (English)

    Hu Jing-Guo; Stamps R L

    2006-01-01

    The rotational anisotropies in the exchange bias structures of ferromagnetism/antiferromagnetism 1/antiferromagnetism 2 are studied in this paper. Based on the model, in which the antiferromagnetism is treated with an Ising mean field theory and the rotational anisotropy is assumed to be related to the field created by the moment induced on the antiferromagnetic layer next to the ferromagnetic layer, we can explain why in experiments for ferromagnetism (FM)/antiferromagntism 1 (AFM1)/antiferromagnetism 2 (AFM2) systems the thickness-dependent rotational anisotropy value is non-monotonic, i.e. it reaches a minimum for this system at a specific thickness of the first antiferromagnetic layer and exhibits oscillatory behaviour. In addition, we find that the temperature-dependent rotational anisotropy value is in good agreement with the experimental result.

  14. Spectral imbalance in the inertial range dynamics of decaying rotating turbulence

    CERN Document Server

    Valente, Pedro C

    2016-01-01

    Direct numerical simulations of homogeneous decaying turbulence with mild background rotation show the existence of a systematic and significant imbalance between the non-linear energy cascade to small scales and its dissipation. By starting the decay from a statistically stationary and fully developed rotating turbulence state, where the dissipation and the energy flux are approximately equal, the data shows a growing imbalance between the two until a maximum is reached when the dissipation is about twice the energy flux. This dichotomy of behaviours during decay is reminiscent of the non-equilibrium and the equilibrium regions previously reported for non-rotating turbulence [P.C. Valente, J.C. Vassilicos, Phys. Rev. Lett. {\\bf 108} 214503 (2012)]. Note, however, that for decaying rotating turbulence the classical scaling of the dissipation rate $\\epsilon \\propto u'^3/L$ (where $u'$ and $L$ are the root mean square fluctuating velocity and the integral length scale, respectively) does not appear to hold duri...

  15. Ecological implications of behavioural syndromes.

    Science.gov (United States)

    Sih, Andrew; Cote, Julien; Evans, Mara; Fogarty, Sean; Pruitt, Jonathan

    2012-03-01

    Interspecific trait variation has long served as a conceptual foundation for our understanding of ecological patterns and dynamics. In particular, ecologists recognise the important role that animal behaviour plays in shaping ecological processes. An emerging area of interest in animal behaviour, the study of behavioural syndromes (animal personalities) considers how limited behavioural plasticity, as well as behavioural correlations affects an individual's fitness in diverse ecological contexts. In this article we explore how insights from the concept and study of behavioural syndromes provide fresh understanding of major issues in population ecology. We identify several general mechanisms for how population ecology phenomena can be influenced by a species or population's average behavioural type, by within-species variation in behavioural type, or by behavioural correlations across time or across ecological contexts. We note, in particular, the importance of behavioural type-dependent dispersal in spatial ecology. We then review recent literature and provide new syntheses for how these general mechanisms produce novel insights on five major issues in population ecology: (1) limits to species' distribution and abundance; (2) species interactions; (3) population dynamics; (4) relative responses to human-induced rapid environmental change; and (5) ecological invasions.

  16. The structure of rotational discontinuities

    Energy Technology Data Exchange (ETDEWEB)

    Neugebauer, M. (California Institute of Technology, Pasadena (USA))

    1989-11-01

    This study examines the structures of a set of rotational discontinuities detected in the solar wind by the ISEE-3 spacecraft. It is found that the complexity of the structure increases as the angle {theta} between the propagation vector k and the magnetic field decreases. For rotational discontinuities that propagate at a large angle to the field with an ion (left-hand) sense of rotation, the magnetic hodograms tend to be flattened, in agreement with prior numerical simulations. When {theta} is large, angular overshoots are often observed at one or both ends of the discontinuity. When the propagation is nearly parallel to the field (i.e., when {theta} is small), many different types of structure are seen, ranging from straight lines, the S-shaped curves, to complex, disorganized shapes.

  17. Electromagnetism of rotating conductors revisited

    Energy Technology Data Exchange (ETDEWEB)

    Redzic, Dragan V. [Faculty of Physics, University of Belgrade, Belgrade (Yugoslavia)]. E-mail: redzic@ff.bg.ac.yu

    2002-03-01

    The charge distribution and electromagnetic fields in a rotating, charged conductor under stationary conditions are investigated, assuming that the electrons are at rest relative to the conductor. The basic equations are found, referred to the inertial rest frame of the rotational axis, in the relativistic case, and applied to the case of a cylindrical conductor. The results obtained are compared with those of Groen and Voeyenli (Groen Oe and Voeyenli K 1982 Eur. J. Phys. 3 210-4) who considered the same problem but without taking into account the relative permittivity of the rotating conductor. It is found that the E- and B-fields do not depend on {epsilon}{sub r} and coincide with those calculated by Groen and Voeyenli; the space and surface charge densities, however, depend on {epsilon}{sub r}. (author)

  18. Rotational Mixing and Lithium Depletion

    CERN Document Server

    Pinsonneault, M H

    2010-01-01

    I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses at a rate which decays with time. New developments related to the possible suppression of mixing at late ages, close binary mergers and their lithium signature, and an alternate origin for dispersion in young cool stars tied to radius anomalies observed in active young stars are discussed. I highlight uncertainties in models of Population II lithium depletion and dispersion related to the treatment of angular momentum loss. Finally, the origins of rotation are tied to conditions in the pre-main sequence, and there is thus some evidence that enviroment and planet formation could impact stellar rotational properties. This may be related to recent observational evidence for cluster to cluster variations in lithium depletion and a connection between the presence of planets and s...

  19. Wormhole shadows in rotating dust

    Science.gov (United States)

    Ohgami, Takayuki; Sakai, Nobuyuki

    2016-09-01

    As an extension of our previous work, which investigated the shadows of the Ellis wormhole surrounded by nonrotating dust, in this paper we study wormhole shadows in a rotating dust flow. First, we derive steady-state solutions of slowly rotating dust surrounding the wormhole by solving relativistic Euler equations. Solving null geodesic equations and radiation transfer equations, we investigate the images of the wormhole surrounded by dust for the above steady-state solutions. Because the Ellis wormhole spacetime possesses unstable circular orbits of photons, a bright ring appears in the image, just as in Schwarzschild spacetime. The bright ring looks distorted due to rotation. Aside from the bright ring, there appear weakly luminous complex patterns by the emission from the other side of the throat. These structure could be detected by high-resolution very-long-baseline-interferometry observations in the near future.

  20. Rotating Rayleigh-Taylor turbulence

    Science.gov (United States)

    Boffetta, G.; Mazzino, A.; Musacchio, S.

    2016-09-01

    The turbulent Rayleigh-Taylor system in a rotating reference frame is investigated by direct numerical simulations within the Oberbeck-Boussinesq approximation. On the basis of theoretical arguments, supported by our simulations, we show that the Rossby number decreases in time, and therefore the Coriolis force becomes more important as the system evolves and produces many effects on Rayleigh-Taylor turbulence. We find that rotation reduces the intensity of turbulent velocity fluctuations and therefore the growth rate of the temperature mixing layer. Moreover, in the presence of rotation the conversion of potential energy into turbulent kinetic energy is found to be less effective, and the efficiency of the heat transfer is reduced. Finally, during the evolution of the mixing layer we observe the development of a cyclone-anticyclone asymmetry.

  1. Rotating Ellis Wormholes in Four Dimensions

    CERN Document Server

    Kleihaus, Burkhard

    2014-01-01

    We present rotating wormhole solutions in General Relativity, which are supported by a phantom scalar field. These solutions evolve from the static Ellis wormhole, when the throat is set into rotation. As the rotational velocity increases, the throat deforms until at a maximal value of the rotational velocity, an extremal Kerr solution is encountered. The rotating wormholes attain a finite mass and quadrupole moment. They exhibit ergospheres and possess bound orbits.

  2. Suicide and suicidal behaviour

    Science.gov (United States)

    Turecki, Gustavo; Brent, David A.

    2017-01-01

    Summary Suicide is a complex public health problem of global dimension. Suicidal behaviour (SB) shows marked differences between genders, age groups, geographic regions and socio-political realities, and variably associates with different risk factors, underscoring likely etiological heterogeneity. Although there is no effective algorithm to predict suicide in clinical practice, improved recognition and understanding of clinical, psychological, sociological, and biological factors may facilitate the detection of high-risk individuals and assist in treatment selection. Psychotherapeutic, pharmacological, or neuromodulatory treatments of mental disorders can often prevent SB; additionally, regular follow-up of suicide attempters by mental health services is key to prevent future SB. PMID:26385066

  3. Corporate Social Behaviour

    DEFF Research Database (Denmark)

    Neergaard, Peter; Rahbek Pedersen, Esben

    2003-01-01

    , human rights and environmental protection. Without a common point of reference in national regulation, managers in multinational enterprises now have to develop their own codes of corporate social behaviour. This has created a growing market for private standards within the field of environmental...... management systems, social accountability, corporate citizenship, occupational health and safety and so forth. However, both the idea of government regulation and the literature acclaiming corporate self-regulation should be met with some scepticism. This paper offers a short assessment of the potentials...

  4. The need for a behavioural analysis of behavioural addictions.

    Science.gov (United States)

    James, Richard J E; Tunney, Richard J

    2017-03-01

    This review discusses research on behavioural addictions (i.e. associative learning, conditioning), with reference to contemporary models of substance addiction and ongoing controversies in the behavioural addictions literature. The role of behaviour has been well explored in substance addictions and gambling but this focus is often absent in other candidate behavioural addictions. In contrast, the standard approach to behavioural addictions has been to look at individual differences, psychopathologies and biases, often translating from pathological gambling indicators. An associative model presently captures the core elements of behavioural addiction included in the DSM (gambling) and identified for further consideration (internet gaming). Importantly, gambling has a schedule of reinforcement that shows similarities and differences from other addictions. While this is more likely than not applicable to internet gaming, it is less clear whether it is so for a number of candidate behavioural addictions. Adopting an associative perspective, this paper translates from gambling to video gaming, in light of the existing debates on this matter and the nature of the distinction between these behaviours. Finally, a framework for applying an associative model to behavioural addictions is outlined, and it's application toward treatment. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. The physical behaviour of gabbroic crystal mush

    Science.gov (United States)

    Humphreys, M.; Namur, O.; Holness, M. B.

    2012-12-01

    Crystal mushes form at the boundary layers of all magma bodies, from lava flows to volcanic conduits to batholiths. The physical behaviour of a crystal mush is important in controlling a number of physical processes, from the origin of crystal-poor rhyolites, and the migration and ascent of granitic magmas, to compaction and differentiation processes in large mafic bodies. As well as strain-rate, the grain-scale microstructure of the mush is an important factor in controlling its physical behaviour, with porosity (amount of residual liquid) being particularly important. One might therefore expect to see a range of different behaviours during the crystallisation of a magma body, depending on the porosity and strain rate at any given point in the crystallisation history. We describe evidence for three different mechanical regimes affecting a gabbroic crystal mush at different scales and residual liquid contents. We focus on the Marginal Border Series of the Skaergaard Intrusion, east Greenland, which crystallised on the steeply dipping sidewalls of the intrusion. It has the advantage that, unlike in most mushes that developed on the chamber floor, thermal gradients and the effects of gravity act in orthogonal directions, allowing shear-related features to be identified and distinguished from thermal effects. The largest-scale effects are evident at the contact between the Marginal Border Series (MBS) and the Layered Series, which crystallised on the floor of the intrusion. The contact is characterised by slumping and faulting of semi-consolidated crystal mush, resulting in slippage and rotation of large packets of relatively coherent igneous 'sediment' down-slope. This process may be analogous to the formation of slumps or rotational landslides in sedimentary systems. At a smaller scale, gravitational instability of the sidewalls caused localised sagging of the crystal mush and resulted in small ductile cracks or tears that filled with interstitial liquid. Finally

  6. Rotated balance in humans due to repetitive rotational movement.

    Science.gov (United States)

    Zakynthinaki, M S; Milla, J Madera; De Durana, A López Diaz; Martínez, C A Cordente; Romo, G Rodríguez; Quintana, M Sillero; Molinuevo, J Sampedro

    2010-03-01

    We show how asymmetries in the movement patterns during the process of regaining balance after perturbation from quiet stance can be modeled by a set of coupled vector fields for the derivative with respect to time of the angles between the resultant ground reaction forces and the vertical in the anteroposterior and mediolateral directions. In our model, which is an adaption of the model of Stirling and Zakynthinaki (2004), the critical curve, defining the set of maximum angles one can lean to and still correct to regain balance, can be rotated and skewed so as to model the effects of a repetitive training of a rotational movement pattern. For the purposes of our study a rotation and a skew matrix is applied to the critical curve of the model. We present here a linear stability analysis of the modified model, as well as a fit of the model to experimental data of two characteristic "asymmetric" elite athletes and to a "symmetric" elite athlete for comparison. The new adapted model has many uses not just in sport but also in rehabilitation, as many work place injuries are caused by excessive repetition of unaligned and rotational movement patterns.

  7. Rotational mixing in close binaries

    CERN Document Server

    de Mink, S E; Langer, N; Yoon, S -Ch; Brott, I; Glebbeek, E; Verkoulen, M; Pols, O R

    2008-01-01

    Rotational mixing is a very important but uncertain process in the evolution of massive stars. We propose to use close binaries to test its efficiency. Based on rotating single stellar models we predict nitrogen surface enhancements for tidally locked binaries. Furthermore we demonstrate the possibility of a new evolutionary scenario for very massive (M > 40 solar mass) close (P < 3 days) binaries: Case M, in which mixing is so efficient that the stars evolve quasi-chemically homogeneously, stay compact and avoid any Roche-lobe overflow, leading to very close (double) WR binaries.

  8. The rotational spectrum of tyrosine.

    Science.gov (United States)

    Pérez, Cristóbal; Mata, Santiago; Cabezas, Carlos; López, Juan C; Alonso, José L

    2015-04-23

    In this work neutral tyrosine has been generated in the gas phase by laser ablation of solid samples, and its most abundant conformers characterized through their rotational spectra. Their identification has been made by comparison between the experimental and ab initio values of the rotational and quadrupole coupling constants. Both conformers are stabilized by an O-H•••N hydrogen bond established within the amino acid skeleton chain and an additional weak N-H•••π hydrogen bond. The observed conformers differ in the orientation of the phenolic -OH group.

  9. Butterflies with rotation and charge

    Science.gov (United States)

    Reynolds, Alan P.; Ross, Simon F.

    2016-11-01

    We explore the butterfly effect for black holes with rotation or charge. We perturb rotating BTZ and charged black holes in 2 + 1 dimensions by adding a small perturbation on one asymptotic region, described by a shock wave in the spacetime, and explore the effect of this shock wave on the length of geodesics through the wormhole and hence on correlation functions. We find the effect of the perturbation grows exponentially at a rate controlled by the temperature; dependence on the angular momentum or charge does not appear explicitly. We comment on issues affecting the extension to higher-dimensional charged black holes.

  10. Butterflies with rotation and charge

    CERN Document Server

    Reynolds, Alan P

    2016-01-01

    We explore the butterfly effect for black holes with rotation or charge. We perturb rotating BTZ and charged black holes in 2+1 dimensions by adding a small perturbation on one asymptotic region, described by a shock wave in the spacetime, and explore the effect of this shock wave on the length of geodesics through the wormhole and hence on correlation functions. We find the effect of the perturbation grows exponentially at a rate controlled by the temperature; dependence on the angular momentum or charge does not appear explicitly. We comment on issues affecting the extension to higher-dimensional charged black holes.

  11. Relativity on Rotated Graph Paper

    CERN Document Server

    Salgado, Roberto B

    2011-01-01

    We present visual calculations in special relativity using spacetime diagrams drawn on graph paper that has been rotated by 45 degrees. The rotated lines represent lightlike directions in Minkowski spacetime, and the boxes in the grid (called "light-clock diamonds") represent units of measurement modeled on the ticks of an inertial observer's lightclock. We show that many quantitative results can be read off a spacetime diagram by counting boxes, using a minimal amount of algebra. We use the Doppler Effect, in the spirit of the Bondi k-calculus, to motivate the method.

  12. Rotationally actuated prosthetic helping hand

    Science.gov (United States)

    Norton, William E. (Inventor); Belcher, Jewell G., Jr. (Inventor); Carden, James R. (Inventor); West, Thomas W. (Inventor)

    1991-01-01

    A prosthetic device has been developed for below-the-elbow amputees. The device consists of a cuff, a stem, a housing, two hook-like fingers, an elastic band for holding the fingers together, and a brace. The fingers are pivotally mounted on a housing that is secured to the amputee's upper arm with the brace. The stem, which also contains a cam, is rotationally mounted within the housing and is secured to the cuff, which fits over the amputee's stump. By rotating the cammed stem between the fingers with the lower arm, the amputee can open and close the fingers.

  13. Rotation sensing with trapped ions

    CERN Document Server

    Campbell, W C

    2016-01-01

    We present a protocol for using trapped ions to measure rotations via matter-wave Sagnac interferometry. The trap allows the interferometer to enclose a large area in a compact apparatus through repeated round-trips in a Sagnac geometry. We show how a uniform magnetic field can be used to close the interferometer over a large dynamic range in rotation speed and measurement bandwidth without losing contrast. Since this technique does not require the ions to be confined in the Lamb-Dicke regime, thermal states with many phonons should be sufficient for operation.

  14. Energy Transfer in Rotating Turbulence

    Science.gov (United States)

    Cambon, Claude; Mansour, Nagi N.; Godeferd, Fabien S.; Rai, Man Mohan (Technical Monitor)

    1995-01-01

    The influence or rotation on the spectral energy transfer of homogeneous turbulence is investigated in this paper. Given the fact that linear dynamics, e.g. the inertial waves regime tackled in an RDT (Rapid Distortion Theory) fashion, cannot Affect st homogeneous isotropic turbulent flow, the study of nonlinear dynamics is of prime importance in the case of rotating flows. Previous theoretical (including both weakly nonlinear and EDQNM theories), experimental and DNS (Direct Numerical Simulation) results are gathered here and compared in order to give a self-consistent picture of the nonlinear effects of rotation on tile turbulence. The inhibition of the energy cascade, which is linked to a reduction of the dissipation rate, is shown to be related to a damping due to rotation of the energy transfer. A model for this effect is quantified by a model equation for the derivative-skewness factor, which only involves a micro-Rossby number Ro(sup omega) = omega'/(2(OMEGA))-ratio of rms vorticity and background vorticity as the relevant rotation parameter, in accordance with DNS and EDQNM results fit addition, anisotropy is shown also to develop through nonlinear interactions modified by rotation, in an intermediate range of Rossby numbers (Ro(omega) = (omega)' and Ro(omega)w greater than 1), which is characterized by a marco-Rossby number Ro(sup L) less than 1 and Ro(omega) greater than 1 which is characterized by a macro-Rossby number based on an integral lengthscale L and the micro-Rossby number previously defined. This anisotropy is mainly an angular drain of spectral energy which tends to concentrate energy in tile wave-plane normal to the rotation axis, which is exactly both the slow and the two-dimensional manifold. In Addition, a polarization of the energy distribution in this slow 2D manifold enhances horizontal (normal to the rotation axis) velocity components, and underlies the anisotropic structure of the integral lengthscales. Finally is demonstrated the

  15. The bead on a rotating hoop revisited: an unexpected resonance

    Science.gov (United States)

    Raviola, Lisandro A.; Véliz, Maximiliano E.; Salomone, Horacio D.; Olivieri, Néstor A.; Rodríguez, Eduardo E.

    2017-01-01

    The bead on a rotating hoop is a typical problem in mechanics, frequently posed to junior science and engineering students in basic physics courses. Although this system has a rich dynamics, it is usually not analysed beyond the point particle approximation in undergraduate textbooks, nor empirically investigated. Advanced textbooks show the existence of bifurcations owing to the system's nonlinear nature, and some papers demonstrate, from a theoretical standpoint, its points of contact with phase transition phenomena. However, scarce experimental research has been conducted to better understand its behaviour. We show in this paper that a minor modification to the problem leads to appealing consequences that can be studied both theoretically and empirically with the basic conceptual tools and experimental skills available to junior students. In particular, we go beyond the point particle approximation by treating the bead as a rigid spherical body, and explore the effect of a slightly non-vertical hoop's rotation axis that gives rise to a resonant behaviour not considered in previous works. This study can be accomplished by means of digital video and open source software. The experience can motivate an engaging laboratory project by integrating standard curriculum topics, data analysis and experimental exploration.

  16. Predicting exercise behaviour : extending the theory of planned behaviour with implementation intentions, dispositional variables, and past behaviour

    OpenAIRE

    Rognerud, Audhild Meckelborg; Wisting, Line Norøm

    2006-01-01

    The present study investigated exercise behaviour over a six-week period in a theory of planned behaviour context, extended with implementation intentions, dispositional variables, and past behaviour. Two waves of questionnaires were used to measure behavioural intention, perceived behavioural control, past behaviour, and three dispositional variables, that is optimism, self-efficacy and action-orientation, as well as actual performance of exercise behaviour. Implementation intentions were ma...

  17. Inclusive Education: Teachers' Intentions and Behaviour Analysed from the Viewpoint of the Theory of Planned Behaviour

    Science.gov (United States)

    Yan, Zi; Sin, Kuen-fung

    2014-01-01

    The theory of planned behaviour (TPB) claims that behaviour can be predicted by behavioural intention and perceived behavioural control, while behavioural intention is a function of attitude towards the behaviour, subjective norm, and perceived behavioural control. This study aims at providing explanation and prediction of teachers' inclusive…

  18. Inclusive Education: Teachers' Intentions and Behaviour Analysed from the Viewpoint of the Theory of Planned Behaviour

    Science.gov (United States)

    Yan, Zi; Sin, Kuen-fung

    2014-01-01

    The theory of planned behaviour (TPB) claims that behaviour can be predicted by behavioural intention and perceived behavioural control, while behavioural intention is a function of attitude towards the behaviour, subjective norm, and perceived behavioural control. This study aims at providing explanation and prediction of teachers' inclusive…

  19. Effect of soccer shoe upper on ball behaviour in curve kicks

    Science.gov (United States)

    Ishii, Hideyuki; Sakurai, Yoshihisa; Maruyama, Takeo

    2014-08-01

    New soccer shoes have been developed by considering various concepts related to kicking, such as curving a soccer ball. However, the effects of shoes on ball behaviour remain unclear. In this study, by using a finite element simulation, we investigated the factors that affect ball behaviour immediately after impact in a curve kick. Five experienced male university soccer players performed one curve kick. We developed a finite element model of the foot and ball and evaluated the validity of the model by comparing the finite element results for the ball behaviour immediately after impact with the experimental results. The launch angle, ball velocity, and ball rotation in the finite element analysis were all in general agreement with the experimental results. Using the validated finite element model, we simulated the ball behaviour. The simulation results indicated that the larger the foot velocity immediately before impact, the larger the ball velocity and ball rotation. Furthermore, the Young's modulus of the shoe upper and the coefficient of friction between the shoe upper and the ball had little effect on the launch angle, ball velocity, and ball rotation. The results of this study suggest that the shoe upper does not significantly influence ball behaviour.

  20. Responding to unprofessional behaviours.

    Science.gov (United States)

    Worthington, Roger; Hays, Richard

    2012-04-01

    Medical educators sometimes have to respond to inappropriate behaviours from doctors in training that have the potential to endanger their future careers and affect the safety and well-being of their patients. The authors led workshops at international meetings using case-based discussion and plenary wrap-ups to reinforce and share the learning outcomes. This paper summarises key points of difference and common themes about how to manage challenging professional behaviours presented by doctors in training that may be of value to tutors and clinical educators. Although the problems encountered had elements in common, experiences varied between countries, schools and programmes as regards processes, procedures and thresholds for launching an investigation. Whereas variations are not unexpected it is important to consider the context and background against which decisions are made. Appropriate responses must take account of professional, legal and ethical guidelines, where they exist. Major inconsistencies in hearings and investigations may not be in anyone's best interests: fairness is core to most notions of justice, whether from the perspective of a doctor in training, clinical educator or member of the public. Therefore, schools and programmes need to take this into account when reviewing processes and procedures. Although the career of a doctor in training is important, it is not the only consideration. If systems fail the public has a right to be concerned, and striving to ensure that medical students graduate to become safe, professional doctors is something of concern to all clinical educators. © Blackwell Publishing Ltd 2012.

  1. Driver behaviour at roadworks.

    Science.gov (United States)

    Walker, Guy; Calvert, Malcolm

    2015-11-01

    There is an incompatibility between how transport engineers think drivers behave in roadworks and how they actually behave. As a result of this incompatibility we are losing approximately a lane's worth of capacity in addition to those closed by the roadworks themselves. The problem would have little significance were it not for the fact a lane of motorway costs approx. £30 m per mile to construct and £43 k a year to maintain, and that many more roadworks are planned as infrastructure constructed 40 or 50 years previously reaches a critical stage in its lifecycle. Given current traffic volumes, and the sensitivity of road networks to congestion, the effects of roadworks need to be accurately assessed. To do this requires a new ergonomic approach. A large-scale observational study of real traffic conditions was used to identify the issues and impacts, which were then mapped to the ergonomic knowledge-base on driver behaviour, and combined to developed practical guidelines to help in modelling future roadworks scenarios with greater behavioural accuracy. Also stemming from the work are novel directions for the future ergonomic design of roadworks themselves.

  2. REM sleep Behaviour Disorder.

    Science.gov (United States)

    Ferini-Strambi, Luigi; Rinaldi, Fabrizio; Giora, Enrico; Marelli, Sara; Galbiati, Andrea

    2016-01-01

    Rapid Eye Movement (REM) sleep Behaviour Disorder (RBD) is a REM sleep parasomnia characterized by loss of the muscle atonia that typically occurs during REM sleep, therefore allowing patients to act out their dreams. RBD manifests itself clinically as a violent behaviour occurring during the night, and is detected at the polysomnography by phasic and/or tonic muscle activity on the electromyography channel. In absence of neurological signs or central nervous system lesions, RBD is defined as idiopathic. Nevertheless, in a large number of cases the development of neurodegenerative diseases in RBD patients has been described, with the duration of the follow-up representing a fundamental aspect. A growing number of clinical, neurophysiologic and neuropsychological studies aimed to detect early markers of neurodegenerative dysfunction in RBD patients. Anyway, the evidence of impaired cortical activity, subtle neurocognitive dysfunction, olfactory and autonomic impairment and neuroimaging brain changes in RBD patients is challenging the concept of an idiopathic form of RBD, supporting the idea of RBD as an early manifestation of a more complex neurodegenerative process.

  3. Consumer behaviour regarding energy products

    National Research Council Canada - National Science Library

    Evelina Gradinaru; Lorant Bucs; Gabriel Bratucu

    2016-01-01

    ... challenge if one considers achieving them sustainably. That being said, the present paper gives emphasis to some theoretical and practical information regarding the consumer behaviour regarding energy products...

  4. Sexual behaviour in young people.

    Science.gov (United States)

    Gerressu, Makeda; Stephenson, Judith M

    2008-02-01

    The purpose of this review was to synthesize major research findings in relation to young people and sexual behaviour from the period 2006-2007. We found several key reviews that advance knowledge in the field of young people and sexual behaviour, including observational studies, both qualitative and quantitative, and intervention studies designed to reduce sexual transmission of HIV in both developed and developing countries. Other reviews focused on same-sex behaviours, victimization within relationships, HIV infection/sexually transmitted infection in travellers, prevention of HIV/sexually transmitted infection and the determinants of sexual behaviour in young people. Powerful and consistent forces sustain gender differences in sexual behaviour. The design of interventions to reduce sexual risk behaviour should take account of these forces that help explain young people's sexual behaviour. Knowledge about the kind of interventions that reduce risk behaviour and should be implemented has improved, although the impact on health outcomes such as pregnancy and HIV/sexually transmitted infection is often uncertain. Effective school sex education needs to be part of much broader strategies to improve sexual health, and there is an urgent need for better evaluation of interventions, especially community interventions. Further longitudinal studies are needed to provide insight into the development of relationships and sexual behaviour as well as the course of acculturation.

  5. The Gaia-ESO Survey: dynamical models of flattened, rotating globular clusters

    Science.gov (United States)

    Jeffreson, S. M. R.; Sanders, J. L.; Evans, N. W.; Williams, A. A.; Gilmore, G. F.; Bayo, A.; Bragaglia, A.; Casey, A. R.; Flaccomio, E.; Franciosini, E.; Hourihane, A.; Jackson, R. J.; Jeffries, R. D.; Jofré, P.; Koposov, S.; Lardo, C.; Lewis, J.; Magrini, L.; Morbidelli, L.; Pancino, E.; Randich, S.; Sacco, G. G.; Worley, C. C.; Zaggia, S.

    2017-08-01

    We present a family of self-consistent axisymmetric rotating globular cluster models which are fitted to spectroscopic data for NGC 362, NGC 1851, NGC 2808, NGC 4372, NGC 5927 and NGC 6752 to provide constraints on their physical and kinematic properties, including their rotation signals. They are constructed by flattening Modified Plummer profiles, which have the same asymptotic behaviour as classical Plummer models, but can provide better fits to young clusters due to a slower turnover in the density profile. The models are in dynamical equilibrium as they depend solely on the action variables. We employ a fully Bayesian scheme to investigate the uncertainty in our model parameters (including mass-to-light ratios and inclination angles) and evaluate the Bayesian evidence ratio for rotating to non-rotating models. We find convincing levels of rotation only in NGC 2808. In the other clusters, there is just a hint of rotation (in particular, NGC 4372 and NGC 5927), as the data quality does not allow us to draw strong conclusions. Where rotation is present, we find that it is confined to the central regions, within radii of R ≤ 2rh. As part of this work, we have developed a novel q-Gaussian basis expansion of the line-of-sight velocity distributions, from which general models can be constructed via interpolation on the basis coefficients.

  6. Numerical investigation of the onset of centrifugal buoyancy in a rotating cavity

    Science.gov (United States)

    Pitz, Diogo B.; Marxen, Olaf; Chew, John

    2016-11-01

    Buoyancy-induced flows in a differentially heated rotating annulus present a multitude of dynamics when control parameters such as rotation rate, temperature difference and Prandtl number are varied. Whilst most of the work in this area has been motivated by applications involving geophysics, the problem of buoyancy-induced convection in rotating systems is also relevant in industrial applications such as the flow between rotating disks of turbomachinery internal air systems, in which buoyancy plays a major role and poses a challenge to accurately predict temperature distributions and heat transfer rates. In such applications the rotational speeds involved are very large, so that the centrifugal accelerations induced are much higher than gravity. In this work we perform direct numerical simulations and linear stability analysis of flow induced by centrifugal buoyancy in a sealed rotating annulus of finite gap with flat end-walls, using a canonical setup representative of an internal air system rotating cavity. The analysis focuses on the behaviour of small-amplitude disturbances added to the base flow, and how those affect the onset of Rossby waves and, ultimately, the transition to a fully turbulent state where convection columns no longer have a well-defined structure. Diogo B. Pitz acknowledges the financial support from the Capes foundation through the Science without Borders program.

  7. Regimes of Axisymmetric Flow and Scaling Laws in a Rotating Annulus with Local Convective Forcing

    Directory of Open Access Journals (Sweden)

    Susie Wright

    2017-07-01

    Full Text Available We present a numerical study of axisymmetric flow in a rotating annulus in which local thermal forcing, via a heated annular ring on the outside of the base and a cooled circular disk in the centre of the top surface, drives convection. This new configuration is a variant of the classical thermally-driven annulus, where uniform heating and cooling are applied through the outer and inner sidewalls respectively. The annulus provides an analogue to a planetary circulation and the new configuration, with its more relaxed vertical thermal boundary conditions, is expected to better emulate vigorous convection in the tropics and polar regions as well as baroclinic instability in the mid-latitude baroclinic zone. Using the Met Office/Oxford Rotating Annulus Laboratory (MORALS code, we have investigated a series of equilibrated, two dimensional axisymmetric flows across a large region of parameter space. These are characterized in terms of their velocity and temperature fields. When rotation is applied several distinct flow regimes may be identified for different rotation rates and strengths of differential heating. These regimes are defined as a function of the ratio of the horizontal Ekman layer thickness to the non-rotating thermal boundary layer thickness and are found to be similar to those identified in previous annulus experiments. Convection without rotation is also considered and the scaling of the heat transport with Rayleigh number is calculated. This is then compared with existing work on the classical annulus as well as horizontal and Rayleigh-Bénard convection. As with previous studies on both rotating and non-rotating convection the system’s behaviour is found to be aspect ratio dependent. This dependence is seen in the scaling of the non-rotating Nusselt number and in transitions between regimes in the rotating case although further investigation is required to fully explain these observations.

  8. Rapidly rotating neutron star progenitors

    CERN Document Server

    Postnov, K A; Kolesnikov, D A; Popov, S B; Porayko, N K

    2016-01-01

    Rotating proto-neutron stars can be important sources of gravitational waves to be searched for by present-day and future interferometric detectors. It was demonstrated by Imshennik that in extreme cases the rapid rotation of a collapsing stellar core may lead to fission and formation of a binary proto-neutron star which subsequently merges due to gravitational wave emission. In the present paper, we show that such dynamically unstable collapsing stellar cores may be the product of a former merger process of two stellar cores in a common envelope. We applied population synthesis calculations to assess the expected fraction of such rapidly rotating stellar cores which may lead to fission and formation of a pair of proto-neutron stars. We have used the BSE population synthesis code supplemented with a new treatment of stellar core rotation during the evolution via effective core-envelope coupling, characterized by the coupling time, $\\tau_c$. The validity of this approach is checked by direct MESA calculations ...

  9. Complications of intertrochanteric rotational osteotomy

    Energy Technology Data Exchange (ETDEWEB)

    Braunstein, E.M.; Weissman, B.N.; Sosman, J.L.; Drew, M.

    1983-11-01

    Intertrochanteric anterior rotational osteotomy is a recently developed surgical procedure to treat osteonecrosis of the femoral head. We reviewed the radiographic findings in four cases to acquaint radiologists with the usual appearance of the procedure and to assess surgical complications. In all cases, immediate postoperative radiographs showed rotation of the necrotic portion of the femoral head anteriorly so that it was no longer weight-bearing. Clinical and radiologic follow-up ranged from 12 to 30 months. In this time, three patients developed complications, including nonunion of the osteotomy, further osteonecrosis with collapse of the femoral head, and worsening pain in the absence of progressive radiologic change. Radiology provides an important means of assessing rotational osteotomy, particularly in demonstrating sufficient rotation of the femoral head to assure nonweight-bearing by diseased bone. Also, surgical complications such as nonunion and hardware loosening may be identified. Nevertheless, the patient may deteriorate clinically even in the absence of radiologic demonstration of disease pregression, and the absence of radiographic change does not assure a successful surgical outcome.

  10. ENGINEERING BULLETIN: ROTATING BIOLOGICAL CONTACTORS

    Science.gov (United States)

    Rotating biological contactors employ aerobic fixed-film treatment to degrade either organic and/or nitrogenous (ammonia-nitrogen) constituents present in aqueous waste streams. ixed-film systems provide a surface to which the biomass can adhere. Treatment is achieved as the wast...

  11. Holder for rotating glass body

    Science.gov (United States)

    Kolleck, Floyd W.

    1978-04-04

    A device is provided for holding and centering a rotating glass body such as a rod or tube. The device includes a tubular tip holder which may be held in a lathe chuck. The device can utilize a variety of centering tips each adapted for a particular configuration, such as a glass O-ring joint or semi-ball joint.

  12. Ultrasonography of the Rotator Cuff

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yong Cheol [Samsung Medica Center, Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)

    2006-09-15

    The ultrasonography (US) is an important modality in evaluating shoulder disease. It is accurate in diagnosing the various shoulder diseases including tendinosis, calcific tendinitis, and subacromial bursitis as well as rotator cuff tears. This article presents a pictorial review of US anatomy of the shoulder, the technical aspects of shoulder US, major types of shoulder pathology, and interventional procedure under US guidance

  13. Rotatable fixture for spray coating

    Science.gov (United States)

    Katvala, V.; Porter, E.; Smith, M.

    1979-01-01

    Fixture that rotates about two axes ensures uniform coating and minimizes handling of coated workpiece. Each side of tile is coated in sequence by moving turntables until surface is perpendicular to spray. Process is repeated until desired thickness has built up.

  14. Rotational splittings for slow to moderate rotators: Latitudinal dependency or higher order effects in \\Omega?

    CERN Document Server

    Ouazzani, R-M

    2012-01-01

    Information about the rotation rate is contained in the low frequency part of power spectra, where signatures of nonuniform surface rotation are expected, as well as in the frequency splittings induced by the internal rotation rate. We wish to figure out whether the differences between the seismic rotation period as determined by a mean rotational splitting, and the rotation period measured from the low frequency peak in the Fourier spectrum (observed for some of CoRoT's targets) can provide constraints on the rotation profile. For uniform moderate rotators,perturbative corrections to second and third order in terms of the rotation angular velocity \\Omega, may mimic differential rotation. We apply our perturbation method to evaluate mode frequencies accurate up to \\Omega^3 for uniform rotation. Effects of latitudinal dependence are calculated in the linear approximation. In \\beta Cephei pulsators models, third order effects become comparable to that of a horizontal shear similar to the solar one at rotation r...

  15. Counter Rotating Fans—An Aircraft Propulsion for the Future?

    Institute of Scientific and Technical Information of China (English)

    Peter Schimming

    2003-01-01

    In the mid seventies a new propulsor for aircraft was designed and investigated-the so-called PROPFAN.With regard to the total pressure increase, it ranges between a conventional propeller and a turbofan with very high bypass ratio.This new propulsion system promised a reduction in fuel consumption of 15 to 25% compared to engines at that time. A lot of propfans (Hamilton Standard, USA) with different numbers of blades and blade shapes have been designed and tested in wind tunnels in order to find an optimum in efficiency, Fig. 1. Parallel to this development GE, USA, made a design of a counter rotating unducted propfan, the so-called UDF, Fig.2. A prototype engine was manufactured and investigated on an in-flight test bed mounted at the MD82 and the B727. Since that time there has not been any further development of propfans (except AN 70 with NK 90—engine, Ukraine, which is more or less a propeller design) due to relatively low fuel prices and technical obstacles. Only technical programs in different countries are still going on in order to prepare a data base for designing counter rotating fans in terms of aeroacoustics, aerodynamics and aeroelasticities.In DLR, Germany, a lot of experimental and numerical work has been undertaken to understand the physical behaviour of the unsteady flow in a counter rotating fan.

  16. Behavioural and Cognitive-Behavioural Treatments of Parasomnias.

    Science.gov (United States)

    Galbiati, Andrea; Rinaldi, Fabrizio; Giora, Enrico; Ferini-Strambi, Luigi; Marelli, Sara

    2015-01-01

    Parasomnias are unpleasant or undesirable behaviours or experiences that occur predominantly during or within close proximity to sleep. Pharmacological treatments of parasomnias are available, but their efficacy is established only for few disorders. Furthermore, most of these disorders tend spontaneously to remit with development. Nonpharmacological treatments therefore represent valid therapeutic choices. This paper reviews behavioural and cognitive-behavioural managements employed for parasomnias. Referring to the ICSD-3 nosology we consider, respectively, NREM parasomnias, REM parasomnias, and other parasomnias. Although the efficacy of some of these treatments is proved, in other cases their clinical evidence cannot be provided because of the small size of the samples. Due to the rarity of some parasomnias, further multicentric researches are needed in order to offer a more complete account of behavioural and cognitive-behavioural treatments efficacy.

  17. Behavioural and Cognitive-Behavioural Treatments of Parasomnias

    Directory of Open Access Journals (Sweden)

    Andrea Galbiati

    2015-01-01

    Full Text Available Parasomnias are unpleasant or undesirable behaviours or experiences that occur predominantly during or within close proximity to sleep. Pharmacological treatments of parasomnias are available, but their efficacy is established only for few disorders. Furthermore, most of these disorders tend spontaneously to remit with development. Nonpharmacological treatments therefore represent valid therapeutic choices. This paper reviews behavioural and cognitive-behavioural managements employed for parasomnias. Referring to the ICSD-3 nosology we consider, respectively, NREM parasomnias, REM parasomnias, and other parasomnias. Although the efficacy of some of these treatments is proved, in other cases their clinical evidence cannot be provided because of the small size of the samples. Due to the rarity of some parasomnias, further multicentric researches are needed in order to offer a more complete account of behavioural and cognitive-behavioural treatments efficacy.

  18. Spin rotators and split Siberian Snakes

    Energy Technology Data Exchange (ETDEWEB)

    Roser, Thomas

    1994-03-01

    The study of spin effects in the collision of polarized high energy beams requires flexible and compact spin rotators to manipulate the beam polarization direction. Design criteria and specific examples are presented for high energy, orbit transparent spin rotators ranging from small angle rotators to be used for the excitation of spin resonances to large angle rotators to be used as Siberian Snakes. It is shown that all the requirements for spin rotators can be met with a simple 6-magnet spin rotator design, for which a complete continuous solution is presented.

  19. Spin rotators and split Siberian Snakes

    Energy Technology Data Exchange (ETDEWEB)

    Roser, T. (Brookhaven National Lab., Upton, NY (United States))

    1994-03-22

    The study of spin effects in the collision of polarized high energy beams requires flexible and compact spin rotators to manipulate the beam polarization direction. Design criteria and specific examples are presented for high energy, orbit transparent spin rotators ranging from small angle rotators to be used for the excitation of spin resonances to large angle rotators to be used as Siberian Snakes. It is shown that all the requirements for spin rotators can be met with a simple 6-magnet spin rotator design, for which a complete continuous solution is presented. (orig.)

  20. Structure of molecules and internal rotation

    CERN Document Server

    Mizushima, San-Ichiro

    1954-01-01

    Structure of Molecules and Internal Rotation reviews early studies on dihalogenoethanes. This book is organized into two parts encompassing 8 chapters that evaluate the Raman effect in ethane derivatives, the energy difference between rotational isomers, and the infrared absorption of ethane derivatives. Some of the topics covered in the book are the potential barrier to internal rotation; nature of the hindering potential; entropy difference between the rotational isomers; internal rotation in butane, pentane, and hexane; and internal rotation in long chain n-paraffins. Other chapters deal wi

  1. On the use of the Fourier Transform to determine the projected rotational velocity of line-profile variable B stars

    CERN Document Server

    Aerts, C; Groot, P J; Degroote, P

    2014-01-01

    The Fourier Transform method is a popular tool to derive the rotational velocities of stars from their spectral line profiles. However, its domain of validity does not include line-profile variables with time-dependent profiles. We investigate the performance of the method for such cases, by interpreting the line-profile variations of spotted B stars, and of pulsating B tars, as if their spectral lines were caused by uniform surface rotation along with macroturbulence. We perform time-series analysis and harmonic least-squares fitting of various line diagnostics and of the outcome of several implementations of the Fourier Transform method. We find that the projected rotational velocities derived from the Fourier Transform vary appreciably during the pulsation cycle whenever the pulsational and rotational velocity fields are of similar magnitude. The macroturbulent velocities derived while ignoring the pulsations can vary with tens of km/s during the pulsation cycle. The temporal behaviour of the deduced rotat...

  2. Internet user behaviour

    Directory of Open Access Journals (Sweden)

    Radbâță, A.

    2011-01-01

    Full Text Available Internet is a useful tool for everybody in a technologically advanced world. As Internet appears and develops, it creates a totally new network environment. The development of commerce on the Internet based on virtual communities has become one of the most successful business models in the world. After analyzing the concept of internet, the e-commerce market and its marketing mix and the benefits and limitations of the Internet, we have presented a few studies on Internet user behaviour. Furthermore, the paper looks at a representative sample of Romanian internet users. The results reveal that the Romanians are using the Internet especially for information gathering, e-mail, entertainment and social networking.

  3. Epigenetics, Behaviour, and Health

    Directory of Open Access Journals (Sweden)

    Szyf Moshe

    2008-03-01

    Full Text Available The long-term effects of behaviour and environmental exposures, particularly during childhood, on health outcomes are well documented. Particularly thought provoking is the notion that exposures to different social environments have a long-lasting impact on human physical health. However, the mechanisms mediating the effects of the environment are still unclear. In the last decade, the main focus of attention was the genome, and interindividual genetic polymorphisms were sought after as the principal basis for susceptibility to disease. However, it is becoming clear that recent dramatic increases in the incidence of certain human pathologies, such as asthma and type 2 diabetes, cannot be explained just on the basis of a genetic drift. It is therefore extremely important to unravel the molecular links between the "environmental" exposure, which is believed to be behind this emerging incidence in certain human pathologies, and the disease's molecular mechanisms. Although it is clear that most human pathologies involve long-term changes in gene function, these might be caused by mechanisms other than changes in the deoxyribonucleic acid (DNA sequence. The genome is programmed by the epigenome, which is composed of chromatin and a covalent modification of DNA by methylation. It is postulated here that "epigenetic" mechanisms mediate the effects of behavioural and environmental exposures early in life, as well as lifelong environmental exposures and the susceptibility to disease later in life. In contrast to genetic sequence differences, epigenetic aberrations are potentially reversible, raising the hope for interventions that will be able to reverse deleterious epigenetic programming.

  4. Reduction of Sample Rotation in Electrostatic Levitation

    Science.gov (United States)

    Hyers, R. W; Johnson, W. L.; Savage, L.; Rogers, J. R.

    2000-01-01

    In many containerless processing systems, control of sample rotation is an important issue. Sample rotation is even more important for microgravity containerless processing systems, where the centrifugal acceleration can approach 1 g for even a small rotation rate. Prior work on rotation control by Rhim focused on driving the sample rotation at a controlled rate for droplet dynamics experiments and measurement of electrical conductivity. His technique allows controlled, fast rotation, but for many microgravity experiments the goal is zero rotation. To minimize sample rotation, two approaches are apparent: first, to identify and balance or eliminate the driving forces for undesired sample rotation, or second, implement a feedback-based rotation control loop in parallel with the position control loop. In this work, we have taken the first approach. To minimize sample rotation, the simplest approach is to identify and balance or eliminate the driving forces for undesired sample rotation. Our experiments show that the dominant driving force for rotation of machined Zr spheres in the MSFC ESL is photon pressure from the heating laser. Experimental results showing the correlation between heating power and torque are compared to theoretical predictions, and a strategy for minimizing the torque due to photon pressure is presented.

  5. Applying statistics in behavioural research

    NARCIS (Netherlands)

    Ellis, J.L.

    2016-01-01

    Applying Statistics in Behavioural Research is written for undergraduate students in the behavioural sciences, such as Psychology, Pedagogy, Sociology and Ethology. The topics range from basic techniques, like correlation and t-tests, to moderately advanced analyses, like multiple regression and MAN

  6. Candidate genes for behavioural ecology

    NARCIS (Netherlands)

    Fitzpatrick, M.J.; Ben-Sahar, Y.; Smid, H.M.; Vet, L.E.M.; Robinson, G.E.; Sokolowski, M.B.

    2005-01-01

    In spite of millions of years of evolutionary divergence, the conservation of gene function is common across distant lineages. As such, genes that are known to influence behaviour in one organism are likely to influence similar behaviours in other organisms. Recent studies of the evolution of behavi

  7. Reconsidering the sedentary behaviour paradigm.

    Directory of Open Access Journals (Sweden)

    Carol Maher

    Full Text Available AIMS: Recent literature has posed sedentary behaviour as an independent entity to physical inactivity. This study investigated whether associations between sedentary behaviour and cardio-metabolic biomarkers remain when analyses are adjusted for total physical activity. METHODS: Cross-sectional analyses were undertaken on 4,618 adults from the 2003/04 and 2005/06 U.S. National Health and Nutrition Examination Survey. Minutes of sedentary behaviour and moderate-to-vigorous physical activity (MVPA, and total physical activity (total daily accelerometer counts minus counts accrued during sedentary minutes were determined from accelerometry. Associations between sedentary behaviour and cardio-metabolic biomarkers were examined using linear regression. RESULTS: Results showed that sedentary behaviour was detrimentally associated with 8/11 cardio-metabolic biomarkers when adjusted for MVPA. However, when adjusted for total physical activity, the associations effectively disappeared, except for C-reactive protein, which showed a very small, favourable association (β = -0.06 and triglycerides, which showed a very small, detrimental association (β = 0.04. Standardised betas suggested that total physical activity was consistently, favourably associated with cardio-metabolic biomarkers (9/11 biomarkers, standardized β = 0.08-0.30 while sedentary behaviour was detrimentally associated with just 1 biomarker (standardized β = 0.12. CONCLUSION: There is virtually no association between sedentary behaviour and cardio-metabolic biomarkers once analyses are adjusted for total physical activity. This suggests that sedentary behaviour may not have health effects independent of physical activity.

  8. Infant Predictors of Behavioural Inhibition

    Science.gov (United States)

    Moehler, Eva; Kagan, Jerome; Oelkers-Ax, Rieke; Brunner, Romuald; Poustka, Luise; Haffner, Johann; Resch, Franz

    2008-01-01

    Behavioural inhibition in the second year of life is a hypothesized predictor for shyness, social anxiety and depression in later childhood, adolescence and even adulthood. To search for the earliest indicators of this fundamental temperamental trait, this study examined whether behavioural characteristics in early infancy can predict behavioural…

  9. Three-dimensional coating and rimming flow: a ring of fluid on a rotating horizontal cylinder

    KAUST Repository

    Leslie, G. A.

    2013-01-29

    The steady three-dimensional flow of a thin, slowly varying ring of Newtonian fluid on either the outside or the inside of a uniformly rotating large horizontal cylinder is investigated. Specifically, we study \\'full-ring\\' solutions, corresponding to a ring of continuous, finite and non-zero thickness that extends all of the way around the cylinder. In particular, it is found that there is a critical solution corresponding to either a critical load above which no full-ring solution exists (if the rotation speed is prescribed) or a critical rotation speed below which no full-ring solution exists (if the load is prescribed). We describe the behaviour of the critical solution and, in particular, show that the critical flux, the critical load, the critical semi-width and the critical ring profile are all increasing functions of the rotation speed. In the limit of small rotation speed, the critical flux is small and the critical ring is narrow and thin, leading to a small critical load. In the limit of large rotation speed, the critical flux is large and the critical ring is wide on the upper half of the cylinder and thick on the lower half of the cylinder, leading to a large critical load. We also describe the behaviour of the non-critical full-ring solution and, in particular, show that the semi-width and the ring profile are increasing functions of the load but, in general, non-monotonic functions of the rotation speed. In the limit of large rotation speed, the ring approaches a limiting non-uniform shape, whereas in the limit of small load, the ring is narrow and thin with a uniform parabolic profile. Finally, we show that, while for most values of the rotation speed and the load the azimuthal velocity is in the same direction as the rotation of the cylinder, there is a region of parameter space close to the critical solution for sufficiently small rotation speed in which backflow occurs in a small region on the upward-moving side of the cylinder. © 2013

  10. FLUID FLOW IN ROTATING HELICAL SQUARE DUCTS

    Institute of Scientific and Technical Information of China (English)

    Chen Hua-jun; Zhang Ben-zhao; Zhang Jin-suo

    2003-01-01

    A numerical study is made for a fully developed laminar flow in rotating helical pipes.Due to the rotation, the Coriolis force can also contribute to the secondary flow.The interaction between rotation, torsion, and curvature complicates the flow characteristics.The effects of rotation and torsion on the flow transitions are studied in details.The results show that there are obvious differences between the flow in rotating ducts and in helical ducts without rotation.Certain hitherto unknown flow patterns are found.The effects of rotation and torsion on the friction factor are also examined.Present results show the characteristics of the fluid flow in rotating helical square ducts.

  11. Area spectrum of slowly rotating black holes

    OpenAIRE

    2010-01-01

    We investigate the area spectrum for rotating black holes which are Kerr and BTZ black holes. For slowly rotating black holes, we use the Maggiore's idea combined with Kunstatter's method to derive their area spectra, which are equally spaced.

  12. SEG Advances in Rotational Seismic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, Robert; Laughlin, Darren; Brune, Bob

    2016-10-17

    Significant advancements in the development of sensors to enable rotational seismic measurements have been achieved. Prototypes are available now to support experiments that help validate the utility of rotational seismic measurements.

  13. Electric Deflection of Rotating Molecules

    CERN Document Server

    Gershnabel, E

    2010-01-01

    We provide a theory of the deflection of polar and non-polar rotating molecules by inhomogeneous static electric field. Rainbow-like features in the angular distribution of the scattered molecules are analyzed in detail. Furthermore, we demonstrate that one may efficiently control the deflection process with the help of short and strong femtosecond laser pulses. In particular the deflection process may by turned-off by a proper excitation, and the angular dispersion of the deflected molecules can be substantially reduced. We study the problem both classically and quantum mechanically, taking into account the effects of strong deflecting field on the molecular rotations. In both treatments we arrive at the same conclusions. The suggested control scheme paves the way for many applications involving molecular focusing, guiding, and trapping by inhomogeneous fields.

  14. Faraday rotation system. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, L.E.; Wang, W.

    1994-07-01

    The Faraday Rotation System (FRS) is one of the advanced laser-based diagnostics developed at DIAL to provide support for the demonstration of prototype-scale coal-fired combustion magnetohydrodynamic (MHD) electrical power generation. Intended for application in the MHD channel, the system directly measures electron density through a measurement of the induced rotation in the polarization of a far infrared laser beam after passing through the MHD flow along the magnetic field lines. A measurement of the induced polarization ellipticity provides a measure of the electron collision frequency which together with the electron density gives the electron conductivity, a crucial parameter for MHD channel performance. The theory of the measurements, a description of the system, its capabilities, laboratory demonstration measurements on seeded flames with comparison to emission absorption measurements, and the current status of the system are presented in this final report.

  15. The chaotic rotation of Hyperion

    Science.gov (United States)

    Wisdom, J.; Peale, S. J.; Mignard, F.

    1984-01-01

    Under the assumption that the satellite is rotating about a principal axis that is normal to its orbit plane, a plot of spin rate-versus-orientation for Hyperion at the pericenter of its orbit has revealed a large, chaotic zone surrounding Hyperion's synchronous spin-orbit state. The chaotic zone is so large that it surrounds the 1/2 and 2 states, and libration in the 3/2 state is not possible. Rotation in the chaotic zone is also attitude-unstable. As tidal dissipation drives Hyperion's spin toward a nearly synchronous value, Hyperion necessarily enters the large chaotic zone, becoming attitude-unstable and tumbling. It is therefore predicted that Hyperion will be found to be tumbling chaotically.

  16. Characterization of the rotating display.

    Science.gov (United States)

    Keyes, J W; Fahey, F H; Harkness, B A; Eggli, D F; Balseiro, J; Ziessman, H A

    1988-09-01

    The rotating display is a useful method for reviewing single photon emission computed tomography (SPECT) data. This study evaluated the requirements for a subjectively pleasing and useful implementation of this technique. Twelve SPECT data sets were modified and viewed by several observers who recorded the minimum framing rates for apparent smooth rotation, 3D effect, effects of image size, and other parameters. The results showed that a minimum of 16 frames was needed for a useful display. Smaller image sizes and more frames were preferred. The recommended minimal framing rate for a 64-frame study is 16-17 frames per second and for a 32-frame study, 12-13 frames per second. Other enhancements also were useful.

  17. Alignment of suprathermally rotating grains

    Science.gov (United States)

    Lazarian, A.

    1995-12-01

    It is shown that mechanical alignment can be efficient for suprathermally rotating grains, provided that they drift with supersonic velocities. Such a drift should be widely spread due to both Alfvenic waves and ambipolar diffusion. Moreover, if suprathermal rotation is caused by grain interaction with a radiative flux, it is shown that mechanical alignment may be present even in the absence of supersonic drift. This means that the range of applicability of mechanical alignment is wider than generally accepted and that it can rival the paramagnetic one. We also study the latter mechanism and re-examine the interplay between poisoning of active sites and desorption of molecules blocking the access to the active sites of H_2 formation, in order to explain the observed poor alignment of small grains and good alignment of large grains. To obtain a more comprehensive picture of alignment, we briefly discuss the alignment by radiation fluxes and by grain magnetic moments.

  18. Whirling skirts and rotating cones

    CERN Document Server

    Guven, Jemal; Müller, Martin Michael

    2013-01-01

    Steady, dihedrally symmetric patterns with sharp peaks may be observed on a spinning skirt, lagging behind the material flow of the fabric. These qualitative features are captured with a minimal model of traveling waves on an inextensible, flexible, generalized-conical sheet rotating about a fixed axis. Conservation laws are used to reduce the dynamics to a quadrature describing a particle in a three-parameter family of potentials. One parameter is associated with the stress in the sheet, the second is the Noether current associated with rotational invariance, and the third is a Rossby number which indicates the relative strength of Coriolis forces. Solutions are quantized by enforcing a topology appropriate to a skirt and a particular choice of dihedral symmetry. A perturbative analysis of nearly axisymmetric cones shows that Coriolis effects are essential in establishing skirt-like solutions. Fully non-linear solutions with three-fold symmetry are presented, which bear a suggestive resemblance to the observ...

  19. Behaviour of dairy cows subjected to an aversive veterinary procedure.

    Directory of Open Access Journals (Sweden)

    Maria José Hötzel

    2009-03-01

    Full Text Available On small dairy farms that lack appropriate handling facilities, cows can be restrained and subjected to veterinary inspection or treatment in their milking environment, which in turn might influence the behaviour of the animals, disrupting routine management. A group of seven dairy cows kept on an intensive rotational pasture system and machine milked twice a day by two familiar handlers were exposed to a thorough clinical examination for three consecutive days. Behavioural data before and after the procedure were analyzed by ANOVA. The behaviour of all the cows during the procedure indicated strong aversiveness. Treatment did not influence the flight distance (metres kept from the veterinarian or from a person unknown by the cows, assessed before and after the procedure (veterinarian: before = 1.2 ± 0.1; after 0.8 ± 0.2; unknown: 1.0 ± 0.2 after 1.2 ± 0.2; p=0.3, nor did it affect the number of agonistic interactions within the group observed before (7.1 ± 2 and after (11.5 ± 3 the procedure (p=0.3, or reactivity score (p=0.2. These results do not support the conclusion that the repeated application of unavoidable aversive veterinary procedures in the milking environment will influence the behaviour of cows during milking or their reactivity to humans.

  20. On the Galactic Spiral Arms Nature as revealed by rotation frequencies

    CERN Document Server

    Roca-Fàbrega, Santi; Figueras, Francesca; Romero-Gómez, Mercè; Velázquez, Hector; Antoja, Teresa; Pichardo, Bárbara

    2013-01-01

    High resolution N-body simulations using different codes and initial condition techniques reveal two different behaviours for the rotation frequency of transient spiral arms like structures. Whereas unbarred disks present spiral arms nearly corotatingwith disk particles, strong barred models (bulged or bulge-less) quickly develop a bar-spiral structure dominant in density, with a pattern speed almost constant in radius. As the bar strength decreases the arm departs from bar rigid rotation and behaves similar to the unbarred case. In strong barred models we detect in the frequency space other subdominant and slower modes at large radii, in agreement with previous studies, however we also detect them in the configuration space. We propose that the distinctive behaviour of the dominant spiral modes can be exploited in order to constraint the nature of Galactic spiral arms by the astrometric survey GAIA and by 2-D spectroscopic surveys like CALIFA and MANGA in external galaxies.

  1. Post-Failure behaviour of pyroclastic debris flow

    Science.gov (United States)

    Scotto di Santolo, Anna; Pellegrino, Anna Maria; Evangelista, Aldo; Coussot, Philippe

    2010-05-01

    The Campania Region is covered by pyroclastic soils accumulated in the last tens of thousands of years as a result of volcanic activity of Campi Flegrei (Phlegrean Fields) and Somma-Vesuvio. These materials cover the slope of the hilly area of Naples and mountain sides of Appennino. Even if they present significant physical and mechanical differences from site to site, they are posing the same geotechnical problems: they are usually unsaturated and collapse due to the increase of water content after prolonged rains creating simple or complex type of landslides (translational or rotational sliding or falls that lead to debris flows). While the mechanical properties of natural soils are the object of a number of research works, the evolution of the material after failure is much less often studied. Typically the post failure behaviour of this material may be "solid-like" or "fluid-like", according to causes that are not well-known. The object of this presentation is the study of the rheological behaviour of the "fluid like" material mixtures with fluid mechanics tools. Three natural pyroclastic deposits were sampled and the soils were remixed with distilled water at different solid volume fractions. The behaviour of these mixtures was investigated like a fluid with a vane rotor rheometer and an inclined plane. The main results are that the rheological behaviour is strongly related to the solid volume concentration, but the transition between solid-like to fluid-like behaviour occurs in a small range of solid concentration slightly different for each material tested. In the fluid-like behaviour the material mixtures behave like a yield stress fluid and a classical Herschel-Bulkley model well represents the experimental data. Nevertheless a hysteresis effect, associated with instability of the material behaviour, is observed for the largest solid concentrations. In that case the material starts to flow abruptly beyond a critical stress and rapidly reaches a relatively

  2. What Is Rotating in Exploratory Factor Analysis?

    Directory of Open Access Journals (Sweden)

    Jason W. Osborne

    2015-01-01

    Full Text Available Exploratory factor analysis (EFA is one of the most commonly-reported quantitative methodology in the social sciences, yet much of the detail regarding what happens during an EFA remains unclear. The goal of this brief technical note is to explore what - rotation- is, what exactly is rotating, and why we use rotation when performing EFAs. Some commentary about the relative utility and desirability of different rotation methods concludes the narrative.

  3. Contra rotative propeller performance estimation

    OpenAIRE

    Coca Casanueva, Vladimir

    2008-01-01

    Due to the continuous increase in the fuel price, the propeller engine solution (the most efficient in fuel saving terms) becomes very attractive to airlines and thus, to aircraft manufacturers. However, airlines aren’t ready to fly an aircraft at lower cruise Mach number than the traditional Mach 0,84, which jeopardizes the fuel efficiency of propellers. At this stage is where the contra-rotative concept appears, which let us to increase the cruise speed while reducing fuel consumption...

  4. Faraday rotation in CMB maps

    Science.gov (United States)

    Ruiz-Granados, Beatriz; Battaner, Eduardo; Florido, Estrella

    2016-10-01

    WMAP CMB polarization maps have been used to detect a low signal of Faraday Rotation (FR). If this detection is not interpreted as simple noise, it could be produced: at the last scattering surface (LSS) (z=1100), being primordial, at Reionization (z=10), in the Milky Way. The second interpretation is favoured here. In this case magnetic fields at Reionization with peak values of the order of 10-8 G should produce this observational FR.

  5. Instabilities in Coaxial Rotating Jets

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The aim of this study is the characterization of the cylindrical mixing layer resulting layer resulting from the interaction of two coaxial swirling jets.The experimental part of this study was performed in a cylindrical water tunnel,permitting an independent rotation of two coaxial jets.The rotations are generated by means of 2×36 blades localized in two swirling chambers.As expected,the evolution of the main instabiltiy modes presents certain differences compared to the plane-mixing-layer case ,Experimental results obtained by tomography showed the existence of vortex rings and streamwise vortex paris in the near field region.This method also permitted the observation of the evolution and interaction of different modes.PIV velocity measurements realized in the meridian plans and the plans perpendicular to the jet axis show that rotation distrots the typical top-hat axial velocity profile.The transition of the the axial velocity profile from jet-like into wake-like is also observed.

  6. The Stellar Activity - Rotation Relationship

    CERN Document Server

    Wright, Nicholas J; Mamajek, Eric E; Henry, Gregory W

    2012-01-01

    Using a new catalog of 824 solar and late-type stars with X-ray luminosities and rotation periods we have studied the relationship between rotation and stellar activity. From an unbiased subset of this sample the power law slope of the unsaturated regime, $L_X/L_{bol}\\propto Ro^\\beta$, is fit as $\\beta=-2.70\\pm0.13$. This is inconsistent with the canonical $\\beta=-2$ slope to a confidence of 5$\\sigma$ and argues for an interface-type dynamo. Super-saturation is observed for the fastest rotators in our sample and its parametric dependencies are explored. Significant correlations are found with both the corotation radius and the excess polar updraft, the latter theory being supported by other observations. We also present a new X-ray population synthesis model of the mature stellar component of our Galaxy and use it to reproduce deep observations of a high Galactic latitude field. The model, XStar, can be used to test models of stellar spin-down and dynamo decay, as well as for estimating stellar X-ray contamin...

  7. Simultaneity on the Rotating Disk

    Science.gov (United States)

    Koks, Don

    2017-04-01

    The disk that rotates in an inertial frame in special relativity has long been analysed by assuming a Lorentz contraction of its peripheral elements in that frame, which has produced widely varying views in the literature. We show that this assumption is unnecessary for a disk that corresponds to the simplest form of rotation in special relativity. After constructing such a disk and showing that observers at rest on it do not constitute a true rotating frame, we choose a "master" observer and calculate a set of disk coordinates and spacetime metric pertinent to that observer. We use this formalism to resolve the "circular twin paradox", then calculate the speed of light sent around the periphery as measured by the master observer, to show that this speed is a function of sent-direction and disk angle traversed. This result is consistent with the Sagnac Effect, but constitutes a finer analysis of that effect, which is normally expressed using an average speed for a full trip of the periphery. We also use the formalism to give a resolution of "Selleri's paradox".

  8. Measuring Thermoforming Behaviour

    Science.gov (United States)

    Michaeli, W.; Hopmann, C.; Ederleh, L.; Begemann, M.

    2011-05-01

    Thermoforming is the process of choice for manufacturing thin-gauge or large-area parts for packaging or technical applications. The process allows low-weight parts to be produced rapidly and economically from thermoplastic semi-finished products. A technical and consequently economical problem is the choice of the right material in combination with the thermoformability of the product. The prediction of thermoformability includes the aspired product features and geometry and defined wall thickness distributions, depending on the specific stretchability of the semifinished product. In practice, thermoformability is estimated by empirical tests with the particular semi-finished product using e.g. staged pyramidal moulds or model cars. With this method, it still cannot be ensured that the product can be thermoformed with the intended properties. A promising alternative is the forming simulation using finite element analysis (FEA). For the simulation, it is necessary to describe the material behaviour using defined material models and the appropriate parameters. Therefore, the stress-/strain-behaviour of the semi-finished product under defined conditions is required. There are several, entirely different measurement techniques used in industry and at research facilities. This paper compares a choice of different measurement techniques to provide an objective basis for future work and research. The semi-finished products are examined with the Membrane-Inflation-Rheometer (MIR), an equibiaxial strain rheometer. A flat sample is heated to the desired temperature in silicone oil. During the measurement, a servohydraulic linear drive advances a piston, thus displacing the hot silicone oil and inflating the specimen to form a sphere. Further measurements are carried out with the Karo IV Laboratory Stretching Machine at Brückner Maschinenbau GmbH & Co. KG, Siegsdorf, Germany. The samples are heated using hot air. During the biaxial stretching, the resulting forces at the

  9. Rotating Polygons on a Fluid Surface

    DEFF Research Database (Denmark)

    Bohr, Tomas; Jansson, Thomas; Haspang, Martin

    The free surface of a rotating fluid will, due to the centrifugal force, be pressed radially outward. If the fluid rotates as a rigid body in a cylindrical container the surface will assume a parabolic shape. If, however, the flow is driven by rotating the bottom plate, the axial symmetry can break...

  10. Magnetism and rotation in relativistic field theory

    Science.gov (United States)

    Mameda, Kazuya; Yamamoto, Arata

    2016-09-01

    We investigate the analogy between magnetism and rotation in relativistic theory. In nonrelativistic theory, the exact correspondence between magnetism and rotation is established in the presence of an external trapping potential. Based on this, we analyze relativistic rotation under external trapping potentials. A Landau-like quantization is obtained by considering an energy-dependent potential.

  11. What Is Rotating in Exploratory Factor Analysis?

    Science.gov (United States)

    Osborne, Jason W.

    2015-01-01

    Exploratory factor analysis (EFA) is one of the most commonly-reported quantitative methodology in the social sciences, yet much of the detail regarding what happens during an EFA remains unclear. The goal of this brief technical note is to explore what "rotation" is, what exactly is rotating, and why we use rotation when performing…

  12. Visualizing Compound Rotations with Virtual Reality

    Science.gov (United States)

    Flanders, Megan; Kavanagh, Richard C.

    2013-01-01

    Mental rotations are among the most difficult of all spatial tasks to perform, and even those with high levels of spatial ability can struggle to visualize the result of compound rotations. This pilot study investigates the use of the virtual reality-based Rotation Tool, created using the Virtual Reality Modeling Language (VRML) together with…

  13. Motor Processes in Children's Mental Rotation

    Science.gov (United States)

    Frick, Andrea; Daum, Moritz M.; Walser, Simone; Mast, Fred W.

    2009-01-01

    Previous studies with adult human participants revealed that motor activities can influence mental rotation of body parts and abstract shapes. In this study, we investigated the influence of a rotational hand movement on mental rotation performance from a developmental perspective. Children at the age of 5, 8, and 11 years and adults performed a…

  14. Trade Space Analysis: Rotational Analyst Research Project

    Science.gov (United States)

    2015-09-01

    TRAC-M-TR-15-028 September 2015 Trade Space Analysis: Rotational Analyst Research Project TRADOC Analysis...PAGE INTENTIONALLY LEFT BLANK TRAC-M-TR-15-028 September 2015 Trade Space Analysis: Rotational Analyst Research Project...NUMBERS Trade Space Analysis : Rotational Analyst Research Project TRAC Project Code 060128 6. AUTHOR(S) Kirstin D Smead 7. PERFORMING

  15. Manual Training of Mental Rotation in Children

    Science.gov (United States)

    Wiedenbauer, Gunnar; Jansen-Osmann, Petra

    2008-01-01

    When deciding whether two stimuli rotated in space are identical or mirror reversed, subjects employ mental rotation to solve the task. In children mental rotation can be trained by extensive repetition of the task, but the improvement seems to rely on the retrieval of previously learned stimuli. We assumed that due to the close relation between…

  16. Visualizing Compound Rotations with Virtual Reality

    Science.gov (United States)

    Flanders, Megan; Kavanagh, Richard C.

    2013-01-01

    Mental rotations are among the most difficult of all spatial tasks to perform, and even those with high levels of spatial ability can struggle to visualize the result of compound rotations. This pilot study investigates the use of the virtual reality-based Rotation Tool, created using the Virtual Reality Modeling Language (VRML) together with…

  17. Sexual behaviour, contraceptive practice and reproductive health ...

    African Journals Online (AJOL)

    Sexual behaviour, contraceptive practice and reproductive health outcomes among ... sexual behaviour, outcomes and care-seeking among university students in ... to collect information on their reproductive health knowledge and behaviour.

  18. Developmental constraints on behavioural flexibility.

    Science.gov (United States)

    Holekamp, Kay E; Swanson, Eli M; Van Meter, Page E

    2013-05-19

    We suggest that variation in mammalian behavioural flexibility not accounted for by current socioecological models may be explained in part by developmental constraints. From our own work, we provide examples of constraints affecting variation in behavioural flexibility, not only among individuals, but also among species and higher taxonomic units. We first implicate organizational maternal effects of androgens in shaping individual differences in aggressive behaviour emitted by female spotted hyaenas throughout the lifespan. We then compare carnivores and primates with respect to their locomotor and craniofacial adaptations. We inquire whether antagonistic selection pressures on the skull might impose differential functional constraints on evolvability of skulls and brains in these two orders, thus ultimately affecting behavioural flexibility in each group. We suggest that, even when carnivores and primates would theoretically benefit from the same adaptations with respect to behavioural flexibility, carnivores may nevertheless exhibit less behavioural flexibility than primates because of constraints imposed by past adaptations in the morphology of the limbs and skull. Phylogenetic analysis consistent with this idea suggests greater evolutionary lability in relative brain size within families of primates than carnivores. Thus, consideration of developmental constraints may help elucidate variation in mammalian behavioural flexibility.

  19. Hormonal mechanisms of cooperative behaviour

    Science.gov (United States)

    Soares, Marta C.; Bshary, Redouan; Fusani, Leonida; Goymann, Wolfgang; Hau, Michaela; Hirschenhauser, Katharina; Oliveira, Rui F.

    2010-01-01

    Research on the diversity, evolution and stability of cooperative behaviour has generated a considerable body of work. As concepts simplify the real world, theoretical solutions are typically also simple. Real behaviour, in contrast, is often much more diverse. Such diversity, which is increasingly acknowledged to help in stabilizing cooperative outcomes, warrants detailed research about the proximate mechanisms underlying decision-making. Our aim here is to focus on the potential role of neuroendocrine mechanisms on the regulation of the expression of cooperative behaviour in vertebrates. We first provide a brief introduction into the neuroendocrine basis of social behaviour. We then evaluate how hormones may influence known cognitive modules that are involved in decision-making processes that may lead to cooperative behaviour. Based on this evaluation, we will discuss specific examples of how hormones may contribute to the variability of cooperative behaviour at three different levels: (i) within an individual; (ii) between individuals and (iii) between species. We hope that these ideas spur increased research on the behavioural endocrinology of cooperation. PMID:20679116

  20. Behavioural management of migraine

    Directory of Open Access Journals (Sweden)

    Helen Brown

    2012-01-01

    Full Text Available It is important to recognise that migraine is a ′biological′ and not a ′psychological′ entity. However, psychological factors can be involved in migraine in 4 different ways:- 1 Migraines can be triggered by psychological stressors; 2 Severe migraine can itself be a cause of significant psychological stress which can, in turn, exacerbate the problem; 3 Even if psychological stress is not significantly involved in the genesis of the headache, pain management techniques can help people cope with their pain more effectively; 4 Longitudinal data demonstrate a complex bidirectional association between mood disorders and migraine. Treatment of a co-existing mood disorder, for example with cognitive behavioural techniques, may therefore reduce the impact of migraine. It would thus appear logical to view medical and psychological approaches as potentially synergistic rather than mutually exclusive. Functional imaging indicates that cognition, emotions, and pain experiences change the way the brain processes pain inputs. This may provide a physiological rationale for psychological interventions in pain management. As most studies of psychological management of migraine have been relatively small and the approach often varies between clinicians, the magnitude of benefit, optimum method of delivery, and the length of intervention are uncertain.

  1. Sexual behaviour of Slovenian primary school pupils - youth sexual behaviour

    National Research Council Canada - National Science Library

    Brcar, Polonca

    2008-01-01

    ...) showed a statistically significant gender difference. In order to evaluate the linear effect of the independent variables on the dependent variable we used Multiple Regression and Correlation according to Ajzen's model of planned behaviour...

  2. Sensing behaviour in healthcare design

    DEFF Research Database (Denmark)

    Thorpe, Julia Rosemary; Hysse Forchhammer, Birgitte; Maier, Anja

    2017-01-01

    We are entering an era of distributed healthcare that should fit and respond to individual needs, behaviour and lifestyles. Designing such systems is a challenging task that requires continuous information about human behaviour on a large scale, for which pervasive sensing (e.g. using smartphones...... specifically on activity and location data that can easily be obtained from smartphones or wearables. We further demonstrate how these are applied in healthcare design using an example from dementia care. Comparing a current and proposed scenario exemplifies how integrating sensor-derived information about...... user behaviour can support the healthcare design goals of personalisation, adaptability and scalability, while emphasising patient quality of life....

  3. The influence of the tangential velocity of inner rotating wall on axial velocity profile of flow through vertical annular pipe with rotating inner surface

    Directory of Open Access Journals (Sweden)

    Sharf Abdusalam M.

    2014-03-01

    Full Text Available In the oil and gas industries, understanding the behaviour of a flow through an annulus gap in a vertical position, whose outer wall is stationary whilst the inner wall rotates, is a significantly important issue in drilling wells. The main emphasis is placed on experimental (using an available rig and computational (employing CFD software investigations into the effects of the rotation speed of the inner pipe on the axial velocity profiles. The measured axial velocity profiles, in the cases of low axial flow, show that the axial velocity is influenced by the rotation speed of the inner pipe in the region of almost 33% of the annulus near the inner pipe, and influenced inversely in the rest of the annulus. The position of the maximum axial velocity is shifted from the centre to be nearer the inner pipe, by increasing the rotation speed. However, in the case of higher flow, as the rotation speed increases, the axial velocity is reduced and the position of the maximum axial velocity is skewed towards the centre of the annulus. There is a reduction of the swirl velocity corresponding to the rise of the volumetric flow rate.

  4. Visual perception of axes of head rotation

    Directory of Open Access Journals (Sweden)

    David Mattijs Arnoldussen

    2013-02-01

    Full Text Available Registration of ego-motion is important to accurately navigate through space. Movements of the head and eye relative to space are registered through the vestibular system and optical flow, respectively. Here, we address three questions concerning the visual registration of self-rotation. 1. Eye-in-head movements provide a link between the motion signals received by sensors in the moving eye and sensors in the moving head. How are these signals combined into an ego-rotation percept? We combined optic flow of simulated forward and rotational motion of the eye with different levels of eye-in-head rotation for a stationary head. We dissociated simulated gaze rotation and head rotation by different levels of eye-in-head pursuit.We found that perceived rotation matches simulated head- not gaze-rotation. This rejects a model for perceived self-rotation that relies on the rotation of the gaze line. Rather, eye-in-head signals serve to transform the optic flow’s rotation information, that specifies rotation of the scene relative to the eye, into a rotation relative to the head. This suggests that transformed visual self-rotation signals may combine with vestibular signals.2. Do transformed visual self-rotation signals reflect the arrangement of the semicircular canals (SCC? Previously, we found sub-regions within MST and V6+ that respond to the speed of the simulated head rotation. Here, we re-analyzed those BOLD signals for the presence of a spatial dissociation related to the axes of visually simulated head rotation, such as have been found in sub-cortical regions of various animals. Contrary, we found a rather uniform BOLD response to simulated rotation along the three SCC axes.3. We investigated if subject’s sensitivity to the direction of the head rotation axis shows SCC axes specifcity. We found that sensitivity to head rotation is rather uniformly distributed, suggesting that in human cortex, visuo-vestibular integration is not arranged into

  5. Rotation and massive close binary evolution

    CERN Document Server

    Langer, N; Yoon, S -C; Hunter, I; Brott, I; Lennon, D J; de Mink, S E; Verheijdt, M

    2008-01-01

    We review the role of rotation in massive close binary systems. Rotation has been advocated as an essential ingredient in massive single star models. However, rotation clearly is most important in massive binaries where one star accretes matter from a close companion, as the resulting spin-up drives the accretor towards critical rotation. Here, we explore our understanding of this process, and its observable consequences. When accounting for these consequences, the question remains whether rotational effects in massive single stars are still needed to explain the observations.

  6. Rotation of microscopic propellers in laser tweezers

    Energy Technology Data Exchange (ETDEWEB)

    Galajda, Peter; Ormos, Pal [Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, PO Box 521, H-6701 (Hungary)

    2002-04-01

    Particles of helical shape trapped in laser tweezers are rotated by light, independently of its polarization state. Light scattering by such propeller-like particles generates the momentum to drive the rotation. The efficiency of the rotation depends on the geometry of the particles. We used photopolymerization of light curing resins to create micrometre-size rotors with different shapes. The rotation of such particles was studied: the effect of shape and size on the rotation, as well as on the stability of the position in the laser tweezers.

  7. Rotating samples in FT-RAMAN spectrometers

    Science.gov (United States)

    De Paepe, A. T. G.; Dyke, J. M.; Hendra, P. J.; Langkilde, F. W.

    1997-11-01

    It is customary to rotate samples in Raman spectroscopy to avoid absorption or sample heating. In FT-Raman experiments the rotation is always shown (typically 30-60 rpm) because higher speeds are thought to generate noise in the spectra. In this article we show that more rapid rotation is possible. A tablet containing maleic acid and one made up of sub-millimetre silica particles with metoprolol succinate as active ingredient were rotated at different speeds, up to 6760 rpm. The FT-Raman spectra were recorded and studied. We conclude that it is perfectly acceptable to rotate samples up to 1500 rpm.

  8. Rotating optical microcavities with broken chiral symmetry

    CERN Document Server

    Sarma, Raktim; Wiersig, Jan; Cao, Hui

    2014-01-01

    We demonstrate in open microcavities with broken chiral symmetry, quasi-degenerate pairs of co-propagating modes in a non-rotating cavity evolve to counter-propagating modes with rotation. The emission patterns change dramatically by rotation, due to distinct output directions of CW and CCW waves. By tuning the degree of spatial chirality, we maximize the sensitivity of microcavity emission to rotation. The rotation-induced change of emission is orders of magnitude larger than the Sagnac effect, pointing to a promising direction for ultrasmall optical gyroscopes.

  9. Examining cotton in rotation with rice and cotton in rotation with other crops using natural experiment

    Science.gov (United States)

    Sun, Ling; Zhu, Zesheng

    2017-08-01

    This paper is to show the ability of remote sensing image analysis combined with statistical analysis to characterize the environmental risk assessment of cotton in rotation with rice and cotton in rotation with other crops in two ways: (1) description of rotation period of cotton in rotation with rice and cotton in rotation with other crops by the observational study or natural experiment; (2) analysis of rotation period calculation of cotton in rotation with rice and cotton in rotation with other crops. Natural experimental results show that this new method is very promising for determining crop rotation period for estimating regional averages of environmental risk. When it is applied to determining crop rotation period, two requested remote sensing images of regional crop are required at least.

  10. Locomotion gaits of a rotating cylinder pair

    Science.gov (United States)

    van Rees, Wim M.; Novati, Guido; Koumoutsakos, Petros; Mahadevan, L.

    2015-11-01

    Using 2D numerical simulations of the Navier-Stokes equations, we demonstrate that a simple pair of rotating cylinders can display a range of locomotion patterns of biological and engineering interest. Steadily counter-rotating the cylinders causes the pair to move akin to a vortex dipole for low rotation rates, but as the rotational velocity is increased the direction of motion reverses. Unsteady rotations lead to different locomotion gaits that resemble jellyfish (for in-phase rotations) and undulating swimmers (for out-of-phase rotations). The small number of parameters for this simple system allows us to systematically map the phase space of these gaits, and allows us to understand the underlying physical mechanisms using a minimal model with implications for biological locomotion and engineered analogs.

  11. Stellar rotation effects in polarimetric microlensing

    CERN Document Server

    Sajadian, Sedighe

    2016-01-01

    It is well known that the polarization signal in microlensing events of hot stars is larger than that of main-sequence stars. Most hot stars rapidly rotate around their stellar axes. The stellar rotation makes ellipticity and gravity-darkening effects which break the spherical symmetry of the source shape and the circular symmetry of the source surface brightness respectively. Hence, it causes a net polarization signal for the source star. This polarization signal should be considered in polarimetry microlensing of fast rotating stars. For moderate rotating stars, lensing can magnify or even characterize small polarization signals due to the stellar rotation through polarimetry observations. The gravity-darkening effect due to a rotating source star makes asymmetric perturbations in polarimetry and photometry microlensing curves whose maximum happens when the lens trajectory crosses the projected position of the rotation pole on the sky plane. The stellar ellipticity makes a time shift (i) in the position of ...

  12. Dimensionality constraints of light induced rotation

    CERN Document Server

    Oroszi, László; Galajda, Péter; Kelemen, Lóránd; Mathesz, Anna; Vicsek, Tamás; Vizsnyiczai, Gaszton; Ormos, Pál

    2015-01-01

    We have studied the conditions of rotation induced by collimated light carrying no angular momentum. Objects of different shapes and optical properties were examined in the nontrivial case where the rotation axis is perpendicular to the direction of light propagation. This geometry offers important advantages for application as it fundamentally broadens the possible practical arrangements to be realised. We found that collimated light cannot drive permanent rotation of 2D or prism-like 3D objects (i.e. fixed cross-sectional profile along the rotation axis) in the case of fully reflective or fully transparent materials. Based on both geometrical optics simulations and theoretical analysis, we derived a general condition for rotation induced by collimated light carrying no angular momentum valid for any arrangement: Permanent rotation is not possible if the scattering interaction is two-dimensional and lossless. In contrast, light induced rotation can be sustained if partial absorption is present or the object ...

  13. Omni rotational driving and steering wheel

    DEFF Research Database (Denmark)

    2008-01-01

    Abstract of WO 2008138346  (A1) There is disclosed a driving and steering wheel (112) module (102) with an omni rotational part (106), the module comprising a flange part (104) fixable on a robot, and the omni rotational part (106) comprises an upper omni rotational part (105) and a driving...... and steering wheel part (108), where the omni rotational part (106) is provided for infinite rotation relative to the flange part (104) by both a drive motor (110) and a steering motor (114) being positionable on the flange part (104), and the driving and steering wheel part (108) is suspended from the upper...... omni rotational part (105) with a suspension (116) such that wheel part (108) can move relatively to the upper omni rotational part (105) in a suspension direction (118), and a reduction gear (120) for gearing the drive torque is provided in the wheel part (108) in order e.g. to assure traction...

  14. Understanding individual routing behaviour.

    Science.gov (United States)

    Lima, Antonio; Stanojevic, Rade; Papagiannaki, Dina; Rodriguez, Pablo; González, Marta C

    2016-03-01

    Knowing how individuals move between places is fundamental to advance our understanding of human mobility (González et al. 2008 Nature 453, 779-782. (doi:10.1038/nature06958)), improve our urban infrastructure (Prato 2009 J. Choice Model. 2, 65-100. (doi:10.1016/S1755-5345(13)70005-8)) and drive the development of transportation systems. Current route-choice models that are used in transportation planning are based on the widely accepted assumption that people follow the minimum cost path (Wardrop 1952 Proc. Inst. Civ. Eng. 1, 325-362. (doi:10.1680/ipeds.1952.11362)), despite little empirical support. Fine-grained location traces collected by smart devices give us today an unprecedented opportunity to learn how citizens organize their travel plans into a set of routes, and how similar behaviour patterns emerge among distinct individual choices. Here we study 92 419 anonymized GPS trajectories describing the movement of personal cars over an 18-month period. We group user trips by origin-destination and we find that most drivers use a small number of routes for their routine journeys, and tend to have a preferred route for frequent trips. In contrast to the cost minimization assumption, we also find that a significant fraction of drivers' routes are not optimal. We present a spatial probability distribution that bounds the route selection space within an ellipse, having the origin and the destination as focal points, characterized by high eccentricity independent of the scale. While individual routing choices are not captured by path optimization, their spatial bounds are similar, even for trips performed by distinct individuals and at various scales. These basic discoveries can inform realistic route-choice models that are not based on optimization, having an impact on several applications, such as infrastructure planning, routing recommendation systems and new mobility solutions. © 2016 The Author(s).

  15. Parametric and mechanical characterization of linear low density polyethylene (LLDPE) using rotational moulding technology

    Indian Academy of Sciences (India)

    P L Ramkumar; D M Kulkarni; V V Chaudhari

    2014-06-01

    In this research work, extensive literature review of the rotational moulding process using linear low density polythene (LLDPE) has been carried out to summarize the present status of the characterization in order to maintain quality and reliability of the products.The present characterization of rotomoulded products using LLDPE is based on the mechanical properties which are being altered by changing process parameters. However, it is observed that in the majority of applications of the products made of LLDPE using rotational moulding technology are prone to cracking failure due to manufacturing defects at room temperature. Therefore, study of fracture characterization of the material is equally important in relation to quality and reliability. In this article, the present characterization of the rotational moulded products using different polymers is summarized in the form of review and the importance of evaluation of the fracture behaviour of rotomoulded products is emphasized.

  16. Trends in information behaviour research

    DEFF Research Database (Denmark)

    Greifeneder, Elke Susanne

    2014-01-01

    Introduction. This paper traces current trends in information behaviour research, both in terms of methods and topics. Results are put into relation to the previous trend analysis by Julien et al. (2011) and Vakkari (2008). Method. Trends derive from a publication analysis taken from information...... behaviour related publication venues between 2012 and 2014. Analysis. Publication titles, authors, years, publication venue, methods and topics were collected and quantitatively analysed. Results. Qualitative methods still dominate information behaviour research. Content analysis and participatory designs...... are gaining terrain. Information seeking is still the major topic of interest. Important newer topics are studies focusing on users’ context and on special needs. Conclusion. Information behaviour research has evolved a great deal over the last years and has taken on new methods and new topics. A discussion...

  17. Norms for environmentally responsible behaviour

    DEFF Research Database (Denmark)

    Thøgersen, John

    assessment of the taxonomy is carried out based of a survey of a random sample of Danish residents 18 years or older. A range of norm constructs were measured with regard to four environmentally relevant behaviours: buying organic milk, buying energy saving light bulbs, source-separating compostable kitchen...... waste, and using public transportation for work and shopping. The frequency of performing the four behaviours was measured as well. The revised taxonomy possesses content, predictive, and nomological validity and satisfactory test-retest reliability. The taxonomy's construct and discriminant validity...... is also supported, with the reservation that the different behavioural references are more than just different methods of measuring the same latent construct(s). People evidently hold different norms for different environmentally responsible behaviours....

  18. Trends in information behaviour research

    DEFF Research Database (Denmark)

    Greifeneder, Elke Susanne

    2014-01-01

    behaviour related publication venues between 2012 and 2014. Analysis. Publication titles, authors, years, publication venue, methods and topics were collected and quantitatively analysed. Results. Qualitative methods still dominate information behaviour research. Content analysis and participatory designs......Introduction. This paper traces current trends in information behaviour research, both in terms of methods and topics. Results are put into relation to the previous trend analysis by Julien et al. (2011) and Vakkari (2008). Method. Trends derive from a publication analysis taken from information...... are gaining terrain. Information seeking is still the major topic of interest. Important newer topics are studies focusing on users’ context and on special needs. Conclusion. Information behaviour research has evolved a great deal over the last years and has taken on new methods and new topics. A discussion...

  19. Customer satisfaction and complaint behaviour

    African Journals Online (AJOL)

    kirstam

    must in the eyes of the customer. This could be ... Coping refers to the psychological and behavioural efforts undertaken ... Tshwane region of Gauteng. ... been used successfully to measure consumers' expectations for and satisfaction/.

  20. Media violence and youth behaviour

    African Journals Online (AJOL)

    QuickSilver

    2003-05-07

    May 7, 2003 ... forms and includes rock music and music videos, advertising, video and computer games as well computers and the internet.(1). In addition, print ... Media exposure is known to influence knowledge, behaviour and value ...

  1. Measuring risky adolescent cycling behaviour.

    Science.gov (United States)

    Feenstra, Hans; Ruiter, Robert A C; Schepers, Jan; Peters, Gjalt-Jorn; Kok, Gerjo

    2011-09-01

    Adolescents are at a greater risk of being involved in traffic accidents than most other age groups, even before they start driving cars. This article aims to determine the factor structure of a self-report questionnaire measuring adolescent risky cycling behaviour, the ACBQ (Adolescent Cycling Behaviour Questionnaire). The questionnaire's structure was based on the widely used Driver Behaviour Questionnaire (DBQ). A sample of secondary school students (N = 1749; age range: 13-18 years) filled out the questionnaire. Factor analysis revealed a three-factor structure underlying the questionnaire, which was confirmed on two equally large portions of the entire sample. These three underlying factors were identified as errors, common violations and exceptional violations. The ACBQ is a useful instrument for measuring adolescents' risky cycling behaviour.

  2. Where is behavioural ecology going?

    Science.gov (United States)

    Owens, Ian P F

    2006-07-01

    Since the 1990s, behavioural ecologists have largely abandoned some traditional areas of interest, such as optimal foraging, but many long-standing challenges remain. Moreover, the core strengths of behavioural ecology, including the use of simple adaptive models to investigate complex biological phenomena, have now been applied to new puzzles outside behaviour. But this strategy comes at a cost. Replication across studies is rare and there have been few tests of the underlying genetic assumptions of adaptive models. Here, I attempt to identify the key outstanding questions in behavioural ecology and suggest that researchers must make greater use of model organisms and evolutionary genetics in order to make substantial progress on these topics.

  3. Differential rotation of geomagnetic field

    Institute of Scientific and Technical Information of China (English)

    WEI Zigang; XU Wenyao

    2003-01-01

    The latitudinal dependence of the westward drift in the main geomagnetic field is examined by using the correlation analysis of moving random pattern. The study reveals the characteristics in the differential rotation of the main field. The results show that the global geomagnetic field drifts westward with an average speed of 0.18°/a during 1900-2000. The westward drift rate is not symmetrical with respect to the equator. The maximum westward drift rate, 0.31°/a, occurs at the latitude --= -15°, forming a Rapid Westward Drift Belt (RDB) around this latitude. Going northward and southward from this belt, the drift rate decreases and reaches the minimum (0.12°/a) at --= 50° and the minimum (0.14°/a) at --= -56°, forming a Northern Hemisphere Slow Westward Drift Belt (N-SDB) and a Southern Hemisphere Slow Westward Drift Belt (S-SDB). Three phases can be detected in the evolution of the westward drift. In the first phase (1900-1940), the RDB dominates the global drift pattern. The westward drifts in this belt are much faster than those in other areas. In the second phase (1940-1960), the drift rates in the RDB are less than those in the first phase, while the drifts in the N-SDB and S-SDB are relatively large. In this phase, the differential rotation becomes less obvious. In the third phase (1960-2000), the westward drift in the RDB increases again and the differential rotation gradually becomes apparent.

  4. Collective behaviour across animal species

    Science.gov (United States)

    Delellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M.; Porfiri, Maurizio

    2014-01-01

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  5. Collective behaviour across animal species.

    Science.gov (United States)

    DeLellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M; Porfiri, Maurizio

    2014-01-16

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  6. Cosmology and galactic rotation curves

    CERN Document Server

    Mannheim, P D

    1995-01-01

    We explore the possibility that the entire departure of galactic rotational velocities from their luminous Newtonian expectation be cosmological in origin, and show that within the framework of conformal gravity (but not Einstein gravity apparently) every static observer sees the overall Hubble flow as a local universal linear potential which is able to account for available data without any need for dark matter. We find that the Universe is necessarily an open one with 3-space scalar curvature given by k = -3.5\\times 10^{-60}cm^{-2}.

  7. Generalization of stochastic visuomotor rotations.

    Directory of Open Access Journals (Sweden)

    Hugo L Fernandes

    Full Text Available Generalization studies examine the influence of perturbations imposed on one movement onto other movements. The strength of generalization is traditionally interpreted as a reflection of the similarity of the underlying neural representations. Uncertainty fundamentally affects both sensory integration and learning and is at the heart of many theories of neural representation. However, little is known about how uncertainty, resulting from variability in the environment, affects generalization curves. Here we extend standard movement generalization experiments to ask how uncertainty affects the generalization of visuomotor rotations. We find that although uncertainty affects how fast subjects learn, the perturbation generalizes independently of uncertainty.

  8. Design of rotating electrical machines

    CERN Document Server

    Pyrhonen , Juha; Hrabovcova , Valeria

    2013-01-01

    In one complete volume, this essential reference presents an in-depth overview of the theoretical principles and techniques of electrical machine design. This timely new edition offers up-to-date theory and guidelines for the design of electrical machines, taking into account recent advances in permanent magnet machines as well as synchronous reluctance machines. New coverage includes: Brand new material on the ecological impact of the motors, covering the eco-design principles of rotating electrical machinesAn expanded section on the design of permanent magnet synchronous machines, now repo

  9. DISCRETE ROTATIONS AND CELLULAR AUTOMATA

    OpenAIRE

    Nouvel, Bertrand

    2006-01-01

    In a discrete space, such as the set of integer-coordinate points, the modelization of isotropy may lead to noticeable theoretical difficulties. At this time, we do not know any gerometric theory on $\\ZZ^n$ that would be suitable to describe the isotropy the same way it is perceived by Euclidean geometry. With respect to this problematic, our aim is to describe some algorithms that would give to the discrete rotations some properties that would be similar to the properties of the Euclidean ro...

  10. Analysis of superdeformed rotational bands

    Science.gov (United States)

    Lalazissis, G. A.; Hara, K.

    1998-07-01

    Available experimental data for the ΔI=2 transition energies in superdeformed bands are analyzed by using an extended one-point formula. The existence of deviations from the smooth behavior is confirmed in many bands. However, we stress that one cannot necessarily speak about regular staggering patterns as they are mostly irregular. We present a simulation of the experimental data in terms of a simple model, which suggests that the irregularities may stem from the presence of irregular kinks in the rotational spectrum. However, at present, where such kinks may come from is an open question.

  11. Rotational Electromagnetic Energy Harvesting System

    Science.gov (United States)

    Dinulovic, Dragan; Brooks, Michael; Haug, Martin; Petrovic, Tomislav

    This paper presents development of the rotational electromagnetic energy harvesting transducer. The transducer is driven mechanically by pushing a button; therefore, the mechanical energy will be converted into electrical energy. The energy harvesting (EH) transducer consists of multilayer planar coils embedded in a PCB, multipolar NdFeB hard magnets, and a mechanical system for movement conversion. The EH transducer generate an energy of about 4 mJ at a load of 10 Ω. The maximum open circuit output voltage is as high as 2 V and the maximum short circuit output current is 800 mA.

  12. Steering behaviour can be modulated by different optic flows during walking.

    Science.gov (United States)

    Sarre, Guillaume; Berard, Jessica; Fung, Joyce; Lamontagne, Anouk

    2008-05-01

    Optic flow is a typical pattern of visual motion that can be used to control locomotion. While the ability to discriminate translational or rotational optic flows have been extensively studied, how these flows control steering during locomotion is not known. The goal of this study was to compare the steering behaviour of subjects subjected to rotational, translational, or combined (rotational added to translational) optic flows with a focus of expansion (FOE) located to the right, left, or straight ahead. Ten healthy young subjects were instructed to walk straight in a virtual room viewed through a helmet mounted display while the location of the FOE was randomly offset. Horizontal trajectory of the body's centre of mass (CoM), as well as rotations of the head, trunk and foot were recorded in coordinates of both the physical and virtual worlds. Results show that subjects experienced a mediolateral shift in CoM opposite to the FOE location, with larger corrections being observed at more eccentric FOE locations. Head and body segment reorientations were only observed for optic flows containing a rotational component. CoM trajectory corrections in the physical world were also of small magnitude, leading to deviation errors in the virtual world. Altogether, these results suggest a profound influence of vision, especially due to the pattern of visual motion, on steering behaviours during locomotion.

  13. Assessment of the rotator cable in various rotator cuff conditions using indirect MR arthrography.

    Science.gov (United States)

    Choo, Hye Jung; Lee, Sun Joo; Kim, Dong Wook; Park, Young-Mi; Kim, Jung-Han

    2014-11-01

    The rotator cable is an important structure providing stress shield to the rotator cuff, similar to the mechanism of suspension bridge. To evaluate the visibility and appearance of the rotator cable in various conditions of the rotator cuff, using indirect magnetic resonance (MR) arthrography. Indirect MR arthrography images from 27 patients (age range, 20-63 years) with normal rotator cuffs, and 47 (age range, 20-73 years) with tendinosis, 32 (age range, 49-71 years) with partial-thickness tears, and 55 (age range, 44-75 years) with full-thickness tears in the supraspinatus and infraspinatus tendons (SST-ISTs) were included in this study. In these various rotator cuff conditions, the visibility and appearance (thickness and width) of the rotator cable and the relationships between the rotator cable appearance, rotator cuff tear size, rotator cuff thickness, and patient's age were assessed. On the sagittal MR images, all rotator cables were visible in the normal rotator cuffs and tendinosis/partial-thickness tears of SST-ISTs. In the order of normal cuff, tendinosis, partial-thickness tear, and full-thickness tear of SST-ISTs, the rotator cable tended to become thicker (1.07, 1.27, 1.32, and 1.59 mm, respectively) and narrower (12.1, 10.68, 10.90, and 8.55 mm, respectively). The thickness of the rotator cable was significantly positively correlated with the rotator cuff thickness in the normal rotator cuffs (coefficient, 0.49; P = 0.010) and tendinosis of SST-ISTs (coefficient, 0.53; P < 0.001), but was not correlated with patients' age. On sagittal plane of indirect MR arthrography, most rotator cables were visible. The appearance of the rotator cable changed according to the rotator cuff condition. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  14. Rotational tumbling of Escherichia coli aggregates under shear

    CERN Document Server

    Portela, R; Almeida, P L; Sobral, R G; Franco, J M; Leal, C R

    2016-01-01

    Growing living cultures of Escherichia coli bacteria were investigated using real-time in situ rheology and rheo-imaging measurements. In the early stages of growth (lag phase), and when subjected to a constant stationary shear, the viscosity slowly increases with the cell's population. As the bacteria reach the exponential phase of growth, the viscosity increases rapidly, with sudden and temporary abrupt decreases and recoveries. At a certain stage, corresponding grossly to the late phase of growth, when the population stabilises, the viscosity also keeps its maximum constant value, with drops and recoveries, for a long period of time. This complex rheological behaviour, which was observed to be shear strain dependent, is a consequence of two coupled effects: the cell density continuous increase and its changing interacting properties. Particular attention was given to the late phase of growth of E. coli populations under shear. Rheo-imaging measurements revealed, near the static plate, a rotational motion o...

  15. The rolling suitcase instability: a coupling between translation and rotation

    Science.gov (United States)

    Facchini, G.; Sekimoto, K.; du Pont, S. Courrech

    2017-06-01

    A two-wheel suitcase or trolley can exhibit undamped rocking oscillations from one wheel to the other when pulled fast enough. We study this instability both experimentally-with a toy model of a suitcase rolling on a treadmill-and theoretically. The suitcase oscillates only if a finite perturbation is applied. This is because intrinsic dissipation occurs when the supporting wheel switches. When unstable, the suitcase either increasingly rocks until overturning or reaches a stable limit cycle. The friction force at the rolling wheels constrains wheels to roll without slipping. This constraint imposes a coupling between the translational motion and the three-dimensional rotational motion of the suitcase that drives the rocking instability. The same behaviours are observed in the experiments and in the simulations. The asymptotic scaling laws we observe in the simulations are explained by means of a simplified model where the coupling force is explicit.

  16. Philanthropic behaviour and motives

    Directory of Open Access Journals (Sweden)

    Vladimír Hyánek

    2013-01-01

    Full Text Available Even though philanthropy tends to be considered a sociological theme rather than an economic one, it poses a number of questions that challenge economists as well. We chose to address the following: How can economists contribute to the theories related to philanthropy? We examine some terms that are used in public economics theory and use them to explore the issues of philanthropy like Samaritan’s Dilemma, the Prisoner’s Dilemma, and the Free-Rider Problem, which we consider to be interesting and inspiring (Stone, 2008. We have to find and identify the social values of donors and volunteers rather than their economic values, because economists are not fully able to explain empathy, altruism, and helpful behaviour using traditional economic principles (Rutherford, 2008. The theoretical frame is supported by relevant empirical data. Before starting a large-scale survey, we decided to conduct smaller pre-research probes into people’s attitudes towards altruism, philanthropy, and giving. Even though our sample was not fully representative, the responses that we collected generated interesting findings about people’s views and attitudes. The first wave of data was collected between February and April 2009; the second wave between February and April 2010.Because of this pilot research mission and because of the budget restriction too, the non-representative sample of 823 respondents has been used; students of our Public Economics study programme were used as interviewers. They have also obtained a proper training of the professional sociologist. Students utilized the face to face interviewing method; non-standardized questions were immediately recorded into the reply form. Questions were divided into three groups with typical characteristics. The first one focuses on personal (individual motives for financial donating (only financial gifts for non-profit organizations. Second part examines the attitudes of individual towards the non

  17. Understanding Pesticide Behaviour At The Catchment Scale

    Science.gov (United States)

    Kannan, N.; White, S. M.; Worrall, F.; Pendlington, D.; Groves, S.

    Pesticides in stream flow at the outlet of a 142ha catchment in Eastern England (Col- worth, Bedfordshire), have been monitored since October 1999. About 50% of the total catchment is directly controlled within one farm and a rotation of wheat, oil seed rape, grass, linseed, beans and peas is grown. The data from this catchment are being used to investigate the performance of the USDA SWAT contaminant transport pack- age at the catchment scale. Three years of stream flow and climate data are available with a useful set of pesticide application and detection data. Following calibration and validation of the hydrology of the catchment, pesticide modelling was carried out for tebuconazole, terbutryn, and terbuthylazine. This paper reports on the results of a sen- sitivity analysis of the model, and the final calibrated pesticide component. Analysis of the results obtained show that the timing and decay of predicted pesticide concen- trations are correct. It is therefore recommended that SWAT can be used as a tool to understand pesticide behaviour at the catchment scale.

  18. Ring wormholes via duality rotations

    Directory of Open Access Journals (Sweden)

    Gary W. Gibbons

    2016-09-01

    Full Text Available We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported by phantom scalar field. Further duality rotations remove the scalar field to yield less well known vacuum metrics of the oblate Zipoy–Voorhees–Weyl class, which describe ring wormholes. The ring encircles the wormhole throat and can have any radius, whereas its tension is always negative and should be less than −c4/4G. If the tension reaches the maximal value, the geometry becomes exactly flat, but the topology remains non-trivial and corresponds to two copies of Minkowski space glued together along the disk encircled by the ring. The geodesics are straight lines, and those which traverse the ring get to the other universe. The ring therefore literally produces a hole in space. Such wormholes could perhaps be created by negative energies concentrated in toroidal volumes, for example by vacuum fluctuations.

  19. Differentiating the differential rotation effect.

    Science.gov (United States)

    Boyarskaya, Evgenia; Hecht, Heiko

    2012-07-01

    As an observer views a picture from different viewing angles, objects in the picture appear to maintain their orientation relative to the observer. For instance, the eyes of a portrait appear to follow the observer as he or she views the image from different angles. We have explored this rotation effect, often called the Mona Lisa effect. We report three experiments that used portrait photographs to test variations of the Mona Lisa effect. The first experiment introduced picture displacements relative to the observer in directions beyond the horizontal plane. The Mona Lisa effect remained robust for vertical and/or diagonal observer displacements. The experiment also included conditions in which the portrait had averted gaze directions. An interaction between picture position relative to the observer and gaze direction was found. The second experiment followed up on very pronounced individual differences, suggesting that the Mona Lisa effect is even stronger than it should be for half of all observers (over-rotators). These individual differences do not correlate with any of the standard personality dimensions (Big Five) or with spatial intelligence. In the third experiment, we extended the experiment to virtual 3D heads using the same gaze directions and picture displacements as for the 2D portrait faces. Besides the picture displacements relative to the observer, we also added observer displacements relative to the picture. 3D pictures showed the Mona Lisa effect, but to a smaller extent than did 2D pictures. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Metalloproteases and rotator cuff disease.

    Science.gov (United States)

    Del Buono, Angelo; Oliva, Francesco; Longo, Umile Giuseppe; Rodeo, Scott A; Orchard, John; Denaro, Vincenzo; Maffulli, Nicola

    2012-02-01

    The molecular changes occurring in rotator cuff tears are still unknown, but much attention has been paid to better understand the role of matrix metalloproteinases (MMP) in the development of tendinopathy. These are potent enzymes that, once activated, can completely degrade all components of the connective tissue, modify the extracellular matrix (ECM), and mediatethe development of painful tendinopathy and tendon rupture. To control the local activity of activated proteinases, the same cells produce tissue inhibitors of metalloproteinases (TIMP) that bind to the enzymes and prevent degradation. The balance between the activities of MMPs and TIMPs regulates tendon remodeling, whereas an imbalance produces a collagen dis-regulation and disturbances intendons. ADAMs (a disintegrin and metalloproteinase) are cell membrane-linked enzymes with proteolytic and cell signaling functions. ADAMTSs (ADAM with thrombospondin motifs) are secreted into the circulation, and constitute a heterogenous family of proteases with both anabolic and catabolic functions. Biologic modulation of endogenous MMP activity to basal levels may reduce pathologic tissue degradation and favorably influence healing after rotator cuff repair. Further studies are needed to better define the mechanism of action, and whether these new strategies are safe and effective in larger models. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  1. A nonsingular rotating black hole

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Sushant G. [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India); University of KwaZulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, Durban (South Africa)

    2015-11-15

    The spacetime singularities in classical general relativity are inevitable, as predicated by the celebrated singularity theorems. However, it is a general belief that singularities do not exist in Nature and that they are the limitations of the general relativity. In the absence of a welldefined quantum gravity, models of regular black holes have been studied. We employ a probability distribution inspired mass function m(r) to replace the Kerr black hole mass M to represent a nonsingular rotating black hole that is identified asymptotically (r >> k, k > 0 constant) exactly as the Kerr-Newman black hole, and as the Kerr black hole when k = 0. The radiating counterpart renders a nonsingular generalization of Carmeli's spacetime as well as Vaidya's spacetime, in the appropriate limits. The exponential correction factor changing the geometry of the classical black hole to remove the curvature singularity can also be motivated by quantum arguments. The regular rotating spacetime can also be understood as a black hole of general relativity coupled to nonlinear electrodynamics. (orig.)

  2. Rotating black hole and quintessence

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Sushant G. [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India); University of KwaZulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, Private Bag 54001, Durban (South Africa)

    2016-04-15

    We discuss spherically symmetric exact solutions of the Einstein equations for quintessential matter surrounding a black hole, which has an additional parameter (ω) due to the quintessential matter, apart from the mass (M). In turn, we employ the Newman-Janis complex transformation to this spherical quintessence black hole solution and present a rotating counterpart that is identified, for α = -e{sup 2} ≠ 0 and ω = 1/3, exactly as the Kerr-Newman black hole, and as the Kerr black hole when α = 0. Interestingly, for a given value of parameter ω, there exists a critical rotation parameter (a = a{sub E}), which corresponds to an extremal black hole with degenerate horizons, while for a < a{sub E}, it describes a nonextremal black hole with Cauchy and event horizons, and no black hole for a > a{sub E}. We find that the extremal value a{sub E} is also influenced by the parameter ω and so is the ergoregion. (orig.)

  3. Reciprocally-Rotating Velocity Obstacles

    KAUST Repository

    Giese, Andrew

    2014-05-01

    © 2014 IEEE. Modern multi-agent systems frequently use highlevel planners to extract basic paths for agents, and then rely on local collision avoidance to ensure that the agents reach their destinations without colliding with one another or dynamic obstacles. One state-of-the-art local collision avoidance technique is Optimal Reciprocal Collision Avoidance (ORCA). Despite being fast and efficient for circular-shaped agents, ORCA may deadlock when polygonal shapes are used. To address this shortcoming, we introduce Reciprocally-Rotating Velocity Obstacles (RRVO). RRVO generalizes ORCA by introducing a notion of rotation for polygonally-shaped agents. This generalization permits more realistic motion than ORCA and does not suffer from as much deadlock. In this paper, we present the theory of RRVO and show empirically that it does not suffer from the deadlock issue ORCA has, permits agents to reach goals faster, and has a comparable collision rate at the cost of performance overhead quadratic in the (typically small) user-defined parameter δ.

  4. Short rotation Wood Crops Program

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L.L.; Ehrenshaft, A.R.

    1990-08-01

    This report synthesizes the technical progress of research projects in the Short Rotation Woody Crops Program for the year ending September 30, 1989. The primary goal of this research program, sponsored by the US Department of Energy's Biofuels and Municipal Waste Technology Division, is the development of a viable technology for producing renewable feedstocks for conversion to biofuels. One of the more significant accomplishments was the documentation that short-rotation woody crops total delivered costs could be $40/Mg or less under optimistic but attainable conditions. By taking advantage of federal subsidies such as those offered under the Conservation Reserve Program, wood energy feedstock costs could be lower. Genetic improvement studies are broadening species performance within geographic regions and under less-than-optimum site conditions. Advances in physiological research are identifying key characteristics of species productivity and response to nutrient applications. Recent developments utilizing biotechnology have achieved success in cell and tissue culture, somaclonal variation, and gene-insertion studies. Productivity gains have been realized with advanced cultural studies of spacing, coppice, and mixed-species trials. 8 figs., 20 tabs.

  5. Ring wormholes via duality rotations

    CERN Document Server

    Gibbons, Gary W

    2016-01-01

    We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported by phantom scalar field. Further duality rotations remove the scalar field to yield less well known vacuum metrics of the oblate Zipoy-Voorhees-Weyl class, which describe ring wormholes. The ring encircles the wormhole throat and can have any radius, whereas its tension is always negative and should be less than $-c^4/4G$. If the tension reaches the maximal value, the geometry becomes exactly flat, but the topology remains non-trivial and corresponds to two copies of Minkowski space glued together along the disk encircled by the ring. The geodesics are straight lines, and those which traverse the ring get to the other universe. The ring therefore literally produces a whole in space. Such wormholes could perhaps be created by negative energies concentrated in toroidal volumes...

  6. Trirotron: triode rotating beam radio frequency amplifier

    Science.gov (United States)

    Lebacqz, Jean V.

    1980-01-01

    High efficiency amplification of radio frequencies to very high power levels including: establishing a cylindrical cloud of electrons; establishing an electrical field surrounding and coaxial with the electron cloud to bias the electrons to remain in the cloud; establishing a rotating electrical field that surrounds and is coaxial with the steady field, the circular path of the rotating field being one wavelength long, whereby the peak of one phase of the rotating field is used to accelerate electrons in a beam through the bias field in synchronism with the peak of the rotating field so that there is a beam of electrons continuously extracted from the cloud and rotating with the peak; establishing a steady electrical field that surrounds and is coaxial with the rotating field for high-energy radial acceleration of the rotating beam of electrons; and resonating the rotating beam of electrons within a space surrounding the second field, the space being selected to have a phase velocity equal to that of the rotating field to thereby produce a high-power output at the frequency of the rotating field.

  7. Particle rotational trapping on a floating electrode by rotating induced-charge electroosmosis.

    Science.gov (United States)

    Ren, Yukun; Liu, Weiyu; Liu, Jiangwei; Tao, Ye; Guo, Yongbo; Jiang, Hongyuan

    2016-09-01

    We describe a novel rotating trait of induced-charge electroosmotic slip above a planar metal surface, a phenomenon termed "Rotating induced-charge electro-osmosis" (ROT-ICEO), in the context of a new microfluidic technology for tunable particle rotation or rotational trap. ROT-ICEO has a dynamic flow stagnation line (FSL) that rotates synchronously with a background circularly polarized electric field. We reveal that the rotating FSL of ROT-ICEO gives rise to a net hydrodynamic torque that is responsible for rotating fluids or particles in the direction of the applied rotating electric field either synchronously or asynchronously, the magnitude of which is adjusted by a balance between rotation of FSL and amplitude of angular-direction flow component oscillating at twice the field frequency. Supported by experimental observation, our physical demonstration with ROT-ICEO proves invaluable for the design of flexible electrokinetic framework in modern microfluidic system.

  8. Moderators of the intention-behaviour and perceived behavioural control-behaviour relationships for leisure-time physical activity

    OpenAIRE

    Godin Gaston; Amireault Steve; Vohl Marie-Claude; Pérusse Louis

    2008-01-01

    Abstract Background Intention is a key determinant of action. However, there is a gap between intention and behavioural performance that remains to be explained. Therefore, the aim of this study was to identify moderators of the intention-behaviour and perceived behavioural control (PBC)- behaviour relationships for leisure-time physical activity. Method This was tested in reference to Ajzen's Theory of Planned Behaviour. A sample of 300 volunteers, 192 women and 108 men, aged 18 to 55, parti...

  9. Viscoelastic behaviour of human blood and polyacrylamide model fluids for heart valve testing

    Science.gov (United States)

    Lerche, Dietmar; Vlastos, Georgios; Koch, Brigitte; Pohl, Manfred; Affeld, Klaus

    1993-06-01

    New heart valves and other cardiovascular assist systems have to be tested for hydrodynamic performance. In place of human blood simple model fluids like glycerol solutions are employed often due to ethical and practical reasons. But blood exhibits complex non-Newtonian and viscoelastic behaviour. Rheological blood properties are reviewed based on literature and own experimental results. Furthermore we studied polymer solutions with respect to blood-like flow behaviour. Rheology was assessed by means of the low shear rotational viscometer (LS 40, Mettler-Toledo, Switzerland) under stationary and dynamic shear conditions (variation of frequency and angular displacement).

  10. Psychological aspects of road user behaviour

    NARCIS (Netherlands)

    Rothengatter, J.A.

    1997-01-01

    The behaviour of road users is an important factor in accident causation. Traffic psychology, defined as ''the study of the behaviour of road users and the psychological processes underlying that behaviour'', attempts to identify the determinants of road user behaviour with the aim of developing eff

  11. Agent-based simulation of animal behaviour

    NARCIS (Netherlands)

    C.M. Jonker (Catholijn); J. Treur

    1998-01-01

    textabstract In this paper it is shown how animal behaviour can be simulated in an agent-based manner. Different models are shown for different types of behaviour, varying from purely reactive behaviour to pro-active, social and adaptive behaviour. The compositional development method for

  12. Psychological aspects of road user behaviour

    NARCIS (Netherlands)

    Rothengatter, J.A.

    The behaviour of road users is an important factor in accident causation. Traffic psychology, defined as ''the study of the behaviour of road users and the psychological processes underlying that behaviour'', attempts to identify the determinants of road user behaviour with the aim of developing

  13. Full Rotational Control of Levitated Silicon Nanorods

    CERN Document Server

    Kuhn, Stefan; Stickler, Benjamin A; Patolsky, Fernando; Hornberger, Klaus; Arndt, Markus; Millen, James

    2016-01-01

    We study a nanofabricated silicon rod levitated in an optical trap. By manipulating the polarization of the light we gain full control over the ro-translational dynamics of the rod. We are able to trap both its centre-of-mass and align it along the linear polarization of the laser field. The rod can be set into rotation at a tuned frequency by exploiting the radiation pressure exerted by elliptically polarized light. The rotational motion of the rod dynamically modifies the optical potential, which allows tuning of the rotational frequency over hundreds of Kilohertz. This ability to trap and control the motion and alignment of nanoparticles opens up the field of rotational optomechanics, rotational ground state cooling and the study of rotational thermodynamics in the underdamped regime.

  14. The effect of rotations on Michelson interferometers

    Science.gov (United States)

    Maraner, Paolo

    2014-11-01

    In the contest of the special theory of relativity, it is shown that uniform rotations induce a phase shift in Michelson interferometers. The effect is second order in the ratio of the interferometer's speed to the speed of light, further suppressed by the ratio of the interferometer's arms length to the radius of rotation and depends on the interferometer's position in the co-rotating frame. The magnitude of the phase shift is just beyond the sensitivity of turntable rotated optical resonators used in present tests of Lorentz invariance. It grows significantly large in Earth's rotated kilometer-scale Fabry-Perot enhanced interferometric gravitational-wave detectors where it appears as a constant bias. The effect can provide the means of sensing center and radius of rotations.

  15. Inertial measurement unit using rotatable MEMS sensors

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Stewart M.; Allen, James J.

    2006-06-27

    A MEM inertial sensor (e.g. accelerometer, gyroscope) having integral rotational means for providing static and dynamic bias compensation is disclosed. A bias compensated MEM inertial sensor is described comprising a MEM inertial sense element disposed on a rotatable MEM stage. A MEM actuator for drives the rotation of the stage between at least two predetermined rotational positions. Measuring and comparing the output of the MEM inertial sensor in the at least two rotational positions allows, for both static and dynamic bias compensation in inertial calculations based on the sensor's output. An inertial measurement unit (IMU) comprising a plurality of independently rotatable MEM inertial sensors and methods for making bias compensated inertial measurements are disclosed.

  16. Inertial measurement unit using rotatable MEMS sensors

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Stewart M. (Albuquerque, NM); Allen, James J. (Albuquerque, NM)

    2007-05-01

    A MEM inertial sensor (e.g. accelerometer, gyroscope) having integral rotational means for providing static and dynamic bias compensation is disclosed. A bias compensated MEM inertial sensor is described comprising a MEM inertial sense element disposed on a rotatable MEM stage. A MEM actuator drives the rotation of the stage between at least two predetermined rotational positions. Measuring and comparing the output of the MEM inertial sensor in the at least two rotational positions allows for both static and dynamic bias compensation in inertial calculations based on the sensor's output. An inertial measurement unit (IMU) comprising a plurality of independently rotatable MEM inertial sensors and methods for making bias compensated inertial measurements are disclosed.

  17. Contained Modes In Mirrors With Sheared Rotation

    Energy Technology Data Exchange (ETDEWEB)

    Abraham J. Fetterman and Nathaniel J. Fisch

    2010-10-08

    In mirrors with E × B rotation, a fixed azimuthal perturbation in the lab frame can appear as a wave in the rotating frame. If the rotation frequency varies with radius, the plasma-frame wave frequency will also vary radially due to the Doppler shift. A wave that propagates in the high rotation plasma region might therefore be evanescent at the plasma edge. This can lead to radially localized Alfven eigenmodes with high azimuthal mode numbers. Contained Alfven modes are found both for peaked and non-peaked rotation profiles. These modes might be useful for alpha channeling or ion heating, as the high azimuthal wave number allows the plasma wave frequency in the rotating frame to exceed the ion cyclotron frequency. __________________________________________________

  18. Inertial measurement unit using rotatable MEMS sensors

    Science.gov (United States)

    Kohler, Stewart M.; Allen, James J.

    2007-05-01

    A MEM inertial sensor (e.g. accelerometer, gyroscope) having integral rotational means for providing static and dynamic bias compensation is disclosed. A bias compensated MEM inertial sensor is described comprising a MEM inertial sense element disposed on a rotatable MEM stage. A MEM actuator drives the rotation of the stage between at least two predetermined rotational positions. Measuring and comparing the output of the MEM inertial sensor in the at least two rotational positions allows for both static and dynamic bias compensation in inertial calculations based on the sensor's output. An inertial measurement unit (IMU) comprising a plurality of independently rotatable MEM inertial sensors and methods for making bias compensated inertial measurements are disclosed.

  19. Confirmation of bistable stellar differential rotation profiles

    CERN Document Server

    Käpylä, P J; Brandenburg, A

    2014-01-01

    (abridged) Context: Solar-like differential rotation is characterized by a rapidly rotating equator and slower poles. However, theoretical models and numerical simulations can also result in a slower equator and faster poles when the overall rotation is slow. Aims: We study the critical rotational influence under which differential rotation flips from solar-like (fast equator, slow poles) to an anti-solar one (slow equator, fast poles). We also estimate the non-diffusive ($\\Lambda$-effect) and diffusive (turbulent viscosity) contributions to the Reynolds stress. Methods: We perform three-dimensional numerical simulations of mildly turbulent convection in spherical wedge geometry. We regulate the convective velocities by varying the amount of heat transported by thermal conduction, turbulent diffusion, and resolved convection. Results: Increasing the efficiency of resolved convection leads to a reduction of the rotational influence on the flow and a sharp transition from solar-like to anti-solar differential r...

  20. Are rotating planes of satellite galaxies ubiquitous?

    CERN Document Server

    Phillips, John I; Bullock, James S; Boylan-Kolchin, Michael

    2015-01-01

    We compare the dynamics of satellite galaxies in the Sloan Digital Sky Survey to simple models in order to test the hypothesis that a large fraction of satellites co-rotate in coherent planes. We confirm the previously-reported excess of co-rotating satellite pairs located near diametric opposition with respect to the host, but show that this signal is unlikely to be due to rotating discs (or planes) of satellites. In particular, no overabundance of co-rotating satellites pairs is observed within $\\sim 20^{\\circ}-50^{\\circ}$ of direct opposition, as would be expected for planar distributions inclined relative to the line-of-sight. Instead, the excess co-rotation for satellite pairs within $\\sim 10^{\\circ}$ of opposition is consistent with random noise associated with undersampling of an underlying isotropic velocity distribution. We conclude that at most $10\\%$ of the hosts in our sample harbor co-rotating satellite planes (as traced by the luminous satellite population).

  1. Physics, Formation and Evolution of Rotating Stars

    CERN Document Server

    Maeder, André

    2009-01-01

    Rotation is ubiquitous at each step of stellar evolution, from star formation to the final stages, and it affects the course of evolution, the timescales and nucleosynthesis. Stellar rotation is also an essential prerequisite for the occurrence of Gamma-Ray Bursts. In this book the author thoroughly examines the basic mechanical and thermal effects of rotation, their influence on mass loss by stellar winds, the effects of differential rotation and its associated instabilities, the relation with magnetic fields and the evolution of the internal and surface rotation. Further, he discusses the numerous observational signatures of rotational effects obtained from spectroscopy and interferometric observations, as well as from chemical abundance determinations, helioseismology and asteroseismology, etc. On an introductory level, this book presents in a didactical way the basic concepts of stellar structure and evolution in "track 1" chapters. The other more specialized chapters form an advanced course on the gradua...

  2. Best behaviour? Ontologies and the formal description of animal behaviour

    KAUST Repository

    Gkoutos, Georgios V.

    2015-07-28

    The development of ontologies for describing animal behaviour has proved to be one of the most difficult of all scientific knowledge domains. Ranging from neurological processes to human emotions, the range and scope needed for such ontologies is highly challenging, but if data integration and computational tools such as automated reasoning are to be fully applied in this important area the underlying principles of these ontologies need to be better established and development needs detailed coordination. Whilst the state of scientific knowledge is always paramount in ontology and formal description framework design, this is a particular problem with neurobehavioural ontologies where our understanding of the relationship between behaviour and its underlying biophysical basis is currently in its infancy. In this commentary, we discuss some of the fundamental problems in designing and using behaviour ontologies, and present some of the best developed tools in this domain. © 2015 Springer Science+Business Media New York

  3. Linking behavioural syndromes and cognition: a behavioural ecology perspective.

    Science.gov (United States)

    Sih, Andrew; Del Giudice, Marco

    2012-10-01

    With the exception of a few model species, individual differences in cognition remain relatively unstudied in non-human animals. One intriguing possibility is that variation in cognition is functionally related to variation in personality. Here, we review some examples and present hypotheses on relationships between personality (or behavioural syndromes) and individual differences in cognitive style. Our hypotheses are based largely on a connection between fast-slow behavioural types (BTs; e.g. boldness, aggressiveness, exploration tendency) and cognitive speed-accuracy trade-offs. We also discuss connections between BTs, cognition and ecologically important aspects of decision-making, including sampling, impulsivity, risk sensitivity and choosiness. Finally, we introduce the notion of cognition syndromes, and apply ideas from theories on adaptive behavioural syndromes to generate predictions on cognition syndromes.

  4. Best behaviour? Ontologies and the formal description of animal behaviour.

    Science.gov (United States)

    Gkoutos, Georgios V; Hoehndorf, Robert; Tsaprouni, Loukia; Schofield, Paul N

    2015-10-01

    The development of ontologies for describing animal behaviour has proved to be one of the most difficult of all scientific knowledge domains. Ranging from neurological processes to human emotions, the range and scope needed for such ontologies is highly challenging, but if data integration and computational tools such as automated reasoning are to be fully applied in this important area the underlying principles of these ontologies need to be better established and development needs detailed coordination. Whilst the state of scientific knowledge is always paramount in ontology and formal description framework design, this is a particular problem with neurobehavioural ontologies where our understanding of the relationship between behaviour and its underlying biophysical basis is currently in its infancy. In this commentary, we discuss some of the fundamental problems in designing and using behaviour ontologies, and present some of the best developed tools in this domain.

  5. The missing link between values and behaviour

    DEFF Research Database (Denmark)

    Brunsø, Karen

    For a long time human values have been perceived as abstrat cognitions representing desired goals or end-states which motivate humnan behaviour. A number of studies have tried to explore the link between values and behaviour, but often different constructs are included as intermediate links betwe...... and lifestyle and behaviour. Based on this appraoch we collected data covering values, lifestyle and behaviour, and estimated the cogntiive hierarchy from values to lifestyle to behaviour by structural equation models....

  6. Agent-based simulation of animal behaviour

    OpenAIRE

    Jonker, C.M.; Treur, J.

    1998-01-01

    In this paper it is shown how animal behaviour can be simulated in an agent-based manner. Different models are shown for different types of behaviour, varying from purely reactive behaviour to pro-active, social and adaptive behaviour. The compositional development method for multi-agent systems DESIRE and its software environment supports the conceptual and detailed design, and execution of these models. Experiments reported in the literature on animal behaviour have been simulated for a num...

  7. Rotating Drive for Electrical-Arc Machining

    Science.gov (United States)

    Fransen, C. D.

    1986-01-01

    Rotating drive improves quality of holes made by electrical-arc machining. Mechanism (Uni-tek, rotary head, or equivalent) attached to electrical-arc system. Drive rotates electrode as though it were mechanical drill, while an arc disintegrates metal in workpiece, thereby creating hole. Rotating electrode method often used in electric-discharge machining. NASA innovation is application of technique to electrical-arc machining.

  8. Dynamics of Rotating, Magnetized Neutron Stars

    OpenAIRE

    Liebling, Steven L.

    2010-01-01

    Using a fully general relativistic implementation of ideal magnetohydrodynamics with no assumed symmetries in three spatial dimensions, the dynamics of magnetized, rigidly rotating neutron stars are studied. Beginning with fully consistent initial data constructed with Magstar, part of the Lorene project, we study the dynamics and stability of rotating, magnetized polytropic stars as models of neutron stars. Evolutions suggest that some of these rotating, magnetized stars may be minimally uns...

  9. Detecting Rotational Superradiance in Fluid Laboratories

    OpenAIRE

    Cardoso, Vitor; Coutant, Antonin; Richartz, Mauricio; Weinfurtner, Silke

    2016-01-01

    Rotational superradiance was predicted theoretically decades ago, and is chiefly responsible for a number of important effects and phenomenology in black-hole physics. However, rotational superradiance has never been observed experimentally. Here, with the aim of probing superradiance in the lab, we investigate the behavior of sound and surface waves in fluids resting in a circular basin at the center of which a rotating cylinder is placed. We show that with a suitable choice for the material...

  10. Behaviour of Lagrangian triangular mixed fluid finite elements

    Indian Academy of Sciences (India)

    S Gopalakrishnan; G Devi

    2000-02-01

    The behaviour of mixed fluid finite elements, formulated based on the Lagrangian frame of reference, is investigated to understand the effects of locking due to incompressibility and irrotational constraints. For this purpose, both linear and quadratic mixed triangular fluid elements are formulated. It is found that there exists a close relationship between the penalty finite element approach that uses reduced/selective numerical integration to alleviate locking, and the mixed finite element approach. That is, performing reduced/selective integration in the penalty approach amounts to reducing the order of pressure interpolation in the mixed finite element approach for obtaining similar results. A number of numerical experiments are performed to determine the optimum degree of interpolation of both the mean pressure and the rotational pressure in order that the twin constraints are satisfied exactly. For this purpose, the benchmark solution of the rigid rectangular tank is used. It is found that, irrespective of the degree of mean and the rotational pressure interpolation, the linear triangle mesh, with or without central bubble function (incompatible mode), locks when both the constraints are enforced simultaneously. However, for quadratic triangle, linear interpolation of the mean pressure and constant rotational pressure ensures exact satisfaction of the constraints and the mesh does not lock. Based on the results obtained from the numerical experiments, a number of important conclusions are arrived at.

  11. Special properties of five-dimensional BPS rotating black holes

    Energy Technology Data Exchange (ETDEWEB)

    Herdeiro, C.A.R. E-mail: car26@damtp.cam.ac.uk

    2000-08-28

    Supersymmetric, rotating, asymptotically flat black holes with a regular horizon are rare configurations in string theory. One example is known in five spacetime dimensions, within the toroidal compactification of type IIB string theory. The existence of such special solution is allowed by the existence of a Chern-Simons coupling in the supergravity theory and by the possibility of imposing a self duality condition on the 'rotation 2-form'. We further exemplify the use of such duality condition by finding a new Brinkmann wave solution in D=6 simple gravity, possessing Killing spinors. We then explore three peculiar features of the aforementioned black holes: (1) Oxidising to D=10 the five-dimensional configuration may be interpreted as a system of D1-D5 branes with a Brinkmann wave propagating along their worldvolume. Unlike its five-dimensional Kaluza-Klein compactification, the universal covering space of this manifold has no causality violations. In other words, causal anomalies can be solved in higher dimensions. From the dual SCFT viewpoint, the causality bound for the compactified spacetime arises as the unitarity bound; (2) The vanishing of the scattering cross section for uncharged scalars and sufficiently high angular momentum of the background is shown still to hold at the level of charged interactions. The same is verified when a non-minimal coupling to the geometry is used. Therefore, the 'repulson' behaviour previously found is universal for non accelerated observers; (3) The solutions are shown to have a non-standard gyromagnetic ratio of g=3. In contrast, the superpartners of a static, BPS, five-dimensional black hole have g=1. At the semi-classical level, we find that a Dirac fermion propagating in the rotating hole background has g=2{+-}1, depending on the spinor direction of the fermion being parallel to Killing or 'anti-Killing' spinors.

  12. Measuring stellar rotation periods with Kepler

    CERN Document Server

    Nielsen, M B; Schunker, H; Karoff, C

    2015-01-01

    We measure rotation periods for 12151 stars in the Kepler field, based on the photometric variability caused by stellar activity. Our analysis returns stable rotation periods over at least six out of eight quarters of Kepler data. This large sample of stars enables us to study the rotation periods as a function of spectral type. We find good agreement with previous studies and vsini measurements for F, G and K stars. Combining rotation periods, B-V color, and gyrochronology relations, we find that the cool stars in our sample are predominantly younger than ~1Gyr.

  13. Optimizing of Culture Conditionin Horizontal Rotating Bioreactor

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionBioreactor is the most important equipment in tissue engineering. It can mimic the micro-environment of cell growth in vitro. At present, horizontal rotating bioreactor is the most advanced equipment for cell culture in the world. 2 Rotating bioreactors2.1 Working principleThere are two kinds of horizontal rotating bioreactor: HARV(high aspect ratio vessel) and RCCS (rotary cell culture system). It is drived by step motor with horizontal rotation, the culture medium and cell is filled between ...

  14. Rotational spectroscopy with an optical centrifuge

    CERN Document Server

    Korobenko, Aleksey; Hepburn, John W; Milner, Valery

    2013-01-01

    We demonstrate a new spectroscopic method for studying electronic transitions in molecules with extremely broad range of angular momentum. We employ an optical centrifuge to create narrow rotational wave packets in the ground electronic state of $^{16}$O$_2$. Using the technique of resonance-enhanced multi-photon ionization, we record the spectrum of multiple ro-vibrational transitions between $X^3\\Sigma_{g}^{-}$ and $C^3\\Pi_{g}$ electronic manifolds of oxygen. Direct control of rotational excitation, extending to rotational quantum numbers as high as $N\\gtrsim 120$, enables us to interpret the complex structure of rotational spectra of $C^3\\Pi_{g}$ beyond thermally accessible levels.

  15. Instability of counter-rotating stellar disks

    Science.gov (United States)

    Hohlfeld, R. G.; Lovelace, R. V. E.

    2015-09-01

    We use an N-body simulation, constructed using GADGET-2, to investigate an accretion flow onto an astrophysical disk that is in the opposite sense to the disk's rotation. In order to separate dynamics intrinsic to the counter-rotating flow from the impact of the flow onto the disk, we consider an initial condition in which the counter-rotating flow is in an annular region immediately exterior the main portion of the astrophysical disk. Such counter-rotating flows are seen in systems such as NGC 4826 (known as the "Evil Eye Galaxy"). Interaction between the rotating and counter-rotating components is due to two-stream instability in the boundary region. A multi-armed spiral density wave is excited in the astrophysical disk and a density distribution with high azimuthal mode number is excited in the counter-rotating flow. Density fluctuations in the counter-rotating flow aggregate into larger clumps and some of the material in the counter-rotating flow is scattered to large radii. Accretion flow processes such as this are increasingly seen to be of importance in the evolution of multi-component galactic disks.

  16. Rotation of vertically oriented objects during earthquakes

    Science.gov (United States)

    Hinzen, Klaus-G.

    2012-10-01

    Vertically oriented objects, such as tombstones, monuments, columns, and stone lanterns, are often observed to shift and rotate during earthquake ground motion. Such observations are usually limited to the mesoseismal zone. Whether near-field rotational ground motion components are necessary in addition to pure translational movements to explain the observed rotations is an open question. We summarize rotation data from seven earthquakes between 1925 and 2009 and perform analog and numeric rotation testing with vertically oriented objects. The free-rocking motion of a marble block on a sliding table is disturbed by a pulse in the direction orthogonal to the rocking motion. When the impulse is sufficiently strong and occurs at the `right' moment, it induces significant rotation of the block. Numeric experiments of a free-rocking block show that the initiation of vertical block rotation by a cycloidal acceleration pulse applied orthogonal to the rocking axis depends on the amplitude of the pulse and its phase relation to the rocking cycle. Rotation occurs when the pulse acceleration exceeds the threshold necessary to provoke rocking of a resting block, and the rocking block approaches its equilibrium position. Experiments with blocks subjected to full 3D strong motion signals measured during the 2009 L'Aquila earthquake confirm the observations from the tests with analytic ground motions. Significant differences in the rotational behavior of a monolithic block and two stacked blocks exist.

  17. Rotational structure in molecular infrared spectra

    CERN Document Server

    di Lauro, Carlo

    2013-01-01

    Recent advances in infrared molecular spectroscopy have resulted in sophisticated theoretical and laboratory methods that are difficult to grasp without a solid understanding of the basic principles and underlying theory of vibration-rotation absorption spectroscopy. Rotational Structure in Molecular Infrared Spectra fills the gap between these recent, complex topics and the most elementary methods in the field of rotational structure in the infrared spectra of gaseous molecules. There is an increasing need for people with the skills and knowledge to interpret vibration-rotation spectra in ma

  18. The effect of rotations on Michelson interferometers

    Energy Technology Data Exchange (ETDEWEB)

    Maraner, Paolo, E-mail: pmaraner@unibz.it

    2014-11-15

    In the contest of the special theory of relativity, it is shown that uniform rotations induce a phase shift in Michelson interferometers. The effect is second order in the ratio of the interferometer’s speed to the speed of light, further suppressed by the ratio of the interferometer’s arms length to the radius of rotation and depends on the interferometer’s position in the co-rotating frame. The magnitude of the phase shift is just beyond the sensitivity of turntable rotated optical resonators used in present tests of Lorentz invariance. It grows significantly large in Earth’s rotated kilometer-scale Fabry–Perot enhanced interferometric gravitational-wave detectors where it appears as a constant bias. The effect can provide the means of sensing center and radius of rotations. - Highlights: • Rotations induce a phase shift in Michelson interferometers. • Earth’s rotation induces a constant bias in Michelson interferometers. • Michelson interferometers can be used to sense center and radius of rotations.

  19. Ultrasound determination of rotator cuff tear repairability

    Science.gov (United States)

    Tse, Andrew K; Lam, Patrick H; Walton, Judie R; Hackett, Lisa

    2015-01-01

    Background Rotator cuff repair aims to reattach the torn tendon to the greater tuberosity footprint with suture anchors. The present study aimed to assess the diagnostic accuracy of ultrasound in predicting rotator cuff tear repairability and to assess which sonographic and pre-operative features are strongest in predicting repairability. Methods The study was a retrospective analysis of measurements made prospectively in a cohort of 373 patients who had ultrasounds of their shoulder and underwent rotator cuff repair. Measurements of rotator cuff tear size and muscle atrophy were made pre-operatively by ultrasound to enable prediction of rotator cuff repairability. Tears were classified following ultrasound as repairable or irreparable, and were correlated with intra-operative repairability. Results Ultrasound assessment of rotator cuff tear repairability has a sensitivity of 86% (p rotator cuff repairability were tear size (p rotator cuff tear. Conclusions Ultrasound assessment is accurate in predicting rotator cuff tear repairability. Tear size or anteroposterior tear length and age were the best predictors of repairability. PMID:27582996

  20. [Rotational stability of angiography catheters].

    Science.gov (United States)

    Schröder, J; Weber, M

    1992-10-01

    Rotatory stability is a parameter that reflects the ability of a catheter to transmit a rotation applied at the outer end to the catheter tip for the purpose of selective probing. A method for measuring the rotatory stability is described, and the results of rotatory stability measurements of 70 different commercially available catheters are reported. There is an almost linear correlation between the rotatory stability and the difference between the respective fourth power of the external and internal diameter or, approximately, to the fourth power of the external diameter for catheters without wire reinforcement. With the same cross-sectional dimensions, the rotatory stability of teflon, polyethylene, and nylon catheters has an approximate ratio of 1:2:4. Wire reinforcement increases rotatory stability by an average factor of about 3. For catheters of calibers 5 F and 6 F, a correlation between the rotatory stability and the weight of the reinforcing wire mesh is apparent.

  1. Modulation field induces universe rotation

    CERN Document Server

    Chen, Chien Yu

    2008-01-01

    Noncommutative field theory is a theory concerning a background field on the string world sheet. Whole of the universe is survived on background field situation. In this paper, we consider a module field on spacetime expansion without modifying commutative relation, and omit the deformed effects by $\\star$ production. Lorentz symmetry is conserved on module and unmodule coordinate, the violation point is under the translation between each others by module expansion. However, considering a background field on spacetime geodesic we could understand that even magnetic force could not be generated by putting a module $Poincar\\check{e}$ boost due to CPT conservation. Which phenomenon, each particle field will be rotated and expanded. Assembling the commutative and anti-commutative null vector by putting an operated coefficients on three orthogonal states. Spacetime is homogeneous but anisotropic, since the energy fluid is not uniformed by a distribution of modulation field. Therefore, concentrating on which signif...

  2. Relativity on rotated graph paper

    Science.gov (United States)

    Salgado, Roberto B.

    2016-05-01

    We demonstrate a method for constructing spacetime diagrams for special relativity on graph paper that has been rotated by 45°. The diagonal grid lines represent light-flash worldlines in Minkowski spacetime, and the boxes in the grid (called "clock diamonds") represent units of measurement corresponding to the ticks of an inertial observer's light clock. We show that many quantitative results can be read off a spacetime diagram simply by counting boxes, with very little algebra. In particular, we show that the squared interval between two events is equal to the signed area of the parallelogram on the grid (called the "causal diamond") with opposite vertices corresponding to those events. We use the Doppler effect—without explicit use of the Doppler formula—to motivate the method.

  3. Wave energy plants: Control strategies for avoiding the stalling behaviour in the Wells turbine

    Energy Technology Data Exchange (ETDEWEB)

    Amundarain, Modesto; Alberdi, Mikel; Garrido, Aitor J.; Garrido, Izaskun; Maseda, Javier [Dept. of Automatic Control and Systems Engineering, EUITI Bilbao, University of the Basque Country, Plaza de la Casilla 3, 48012 Bilbao (Spain)

    2010-12-15

    This study analyzes the problem of the stalling behaviour in Wells turbines, one of the most widely used turbines in wave energy plants. For this purpose two different control strategies are presented and compared. In the first one, a rotational speed control system is employed to appropriately adapt the speed of the double-fed induction generator coupling to the turbine, according to the pressure drop entry. In the second control strategy, an airflow control regulates the power generated by the turbine generator module by means of the modulation valve avoiding the stalling behaviour. It is demonstrated that the proposed rotational speed control design adequately matches the desired relationship between the slip of the double-fed induction generator and the pressure drop input, whilst the valve control using a traditional PID controller successfully governs the flow that modulates the pressure drop across the turbine. (author)

  4. Moderators of the intention-behaviour and perceived behavioural control-behaviour relationships for leisure-time physical activity

    Directory of Open Access Journals (Sweden)

    Godin Gaston

    2008-02-01

    Full Text Available Abstract Background Intention is a key determinant of action. However, there is a gap between intention and behavioural performance that remains to be explained. Therefore, the aim of this study was to identify moderators of the intention-behaviour and perceived behavioural control (PBC- behaviour relationships for leisure-time physical activity. Method This was tested in reference to Ajzen's Theory of Planned Behaviour. A sample of 300 volunteers, 192 women and 108 men, aged 18 to 55, participated in the study. At baseline, the participants completed a self-administrated psychosocial questionnaire assessing Ajzen's theory variables (i.e., intention and perceived behavioural control. The behavioural measure was obtained by mail three months later. Results Multiple hierarchical regression analyses indicated that age and annual income moderated the intention-behaviour and PBC-behaviour relationships. However, in the final model predicting behaviour (R2 = .46, only the interaction term of PBC by annual income (β = .24, p = 0.0003 significantly contributed to the prediction of behaviour along with intention (β = .49, p = 0.0009 and past behaviour (β = .44, p Conclusion Physical activity promotion programs would benefit not only from focusing on increasing the intention of low intenders, but also from targeting factors that moderate the perceived behavioural control-behaviour relationships.

  5. Moderators of the intention-behaviour and perceived behavioural control-behaviour relationships for leisure-time physical activity

    Science.gov (United States)

    Amireault, Steve; Godin, Gaston; Vohl, Marie-Claude; Pérusse, Louis

    2008-01-01

    Background Intention is a key determinant of action. However, there is a gap between intention and behavioural performance that remains to be explained. Therefore, the aim of this study was to identify moderators of the intention-behaviour and perceived behavioural control (PBC)- behaviour relationships for leisure-time physical activity. Method This was tested in reference to Ajzen's Theory of Planned Behaviour. A sample of 300 volunteers, 192 women and 108 men, aged 18 to 55, participated in the study. At baseline, the participants completed a self-administrated psychosocial questionnaire assessing Ajzen's theory variables (i.e., intention and perceived behavioural control). The behavioural measure was obtained by mail three months later. Results Multiple hierarchical regression analyses indicated that age and annual income moderated the intention-behaviour and PBC-behaviour relationships. However, in the final model predicting behaviour (R2 = .46), only the interaction term of PBC by annual income (β = .24, p = 0.0003) significantly contributed to the prediction of behaviour along with intention (β = .49, p = 0.0009) and past behaviour (β = .44, p < 0.0001). Conclusion Physical activity promotion programs would benefit not only from focusing on increasing the intention of low intenders, but also from targeting factors that moderate the perceived behavioural control-behaviour relationships. PMID:18241339

  6. Consumer behaviour and the environment

    DEFF Research Database (Denmark)

    Thøgersen, John

    2005-01-01

    -style are not easily achieved, however. In a report issued by United Na-tions Secretary-General Kofi Annan in preparation for the Johannesburg Summit it was concluded that "Progress towards the goals established at Rio has been slower than anticipated and in some respects conditions are worse than they were ten years...... for the environmental cause, but for facilitating environmentally responsible behaviour in many specific ways. Research dealing with the diverse roles of information in the environmental field shows a need to distinguish between different forms and objectives of information, but also, it needs to be stressed......, that information alone is usually not sufficient to change behaviour (Stern, 1999). My aim here is to present a broad-brush overview of some of the most important roles that information has been found to play as a tool for pro-moting environmentally responsible consumer behaviour. Because this publication...

  7. Norms for environmentally responsible behaviour

    DEFF Research Database (Denmark)

    Thøgersen, John

    The currently used concept of personal or moral norms is ambiguous with regard to its motivational content. Therefore, a revision of the norm taxonomy is suggested, implying a distinction between three types of personal norms, called introjected, identified, and integrated norms. A preliminary...... assessment of the taxonomy is carried out based of a survey of a random sample of Danish residents 18 years or older. A range of norm constructs were measured with regard to four environmentally relevant behaviours: buying organic milk, buying energy saving light bulbs, source-separating compostable kitchen...... is also supported, with the reservation that the different behavioural references are more than just different methods of measuring the same latent construct(s). People evidently hold different norms for different environmentally responsible behaviours....

  8. Retailer buying behaviour: A review

    DEFF Research Database (Denmark)

    Hansen, Tommy Holm; Skytte, Hans

    1998-01-01

    With centralised buying organisations, growth in market coverage and turn over retailers have become gatekeepers to the consumer markets. Therefore, knowledge about retailers' and trade buyers' buying behaviour has become important to producers. W review the literature on retailer buying behaviour...... and find that research findings appear scattered and unrelated. Most of the previous research has been concerning with generating lists of criteria used by retailers when deciding whether or not t accept a new product. Other areas that have caught the interest of researcher are: the role of buying...... committees, the relationship with manufacturers, European buying alliances, the use of information, retail buyer task, sales man influences, acce of trade deals, country or origin effects and new information technology. Keywords Retailer buying behaviour, review, buying criteria, retailing, assortment...

  9. Control of molecular rotation in the limit of extreme rotational excitation

    CERN Document Server

    Milner, V

    2015-01-01

    Laser control of molecular rotation is an area of active research. A number of recent studies has aimed at expanding the reach of rotational control to extreme, previously inaccessible rotational states, as well as controlling the directionality of molecular rotation. Dense ensembles of molecules undergoing ultrafast uni-directional rotation, known as molecular superrotors, are anticipated to exhibit unique properties, from spatially anisotropic diffusion and vortex formation to the creation of powerful acoustic waves and tuneable THz radiation. Here we describe our recent progress in controlling molecular rotation in the regime of high rotational excitation. We review two experimental techniques of producing uni-directional rotational wave packets with a "chiral train" of femtosecond pulses and an "optical centrifuge". Three complementary detection methods, enabling the direct observation, characterization and control of the superrotor states, are outlined: the one based on coherent Raman scattering, and two...

  10. Differentially-rotating neutron star models with a parametrized rotation profile

    CERN Document Server

    Galeazzi, Filippo; Eriguchi, Yoshiharu

    2011-01-01

    We analyze the impact of the choice rotation law on equilibrium sequences of relativistic differentially-rotating neutron stars in axisymmetry. The maximum allowed mass for each model is strongly affected by the distribution of angular velocity along the radial direction and by the consequent degree of differential rotation. In order to study the wide parameter space implied by the choice of rotation law, we introduce a functional form that generalizes the so called "j-const. law" adopted in all previous work. Using this new rotation law we reproduce the angular velocity profile of differentially-rotating remnants from the coalescence of binary neutron stars in various 3-dimensional dynamical simulations. We compute equilibrium sequences of differentially rotating stars with a polytropic equation of state starting from the spherically symmetric static case. By analyzing the sequences at constant ratio, T/|W|, of rotational kinetic energy to gravitational binding energy, we find that the parameters that best d...

  11. On the symmetrization of rotational spectra for freely rotating linear molecules

    Science.gov (United States)

    Borysow, Aleksandra; Moraldi, Massimo

    It is demonstrated that the symmetrization of a quantum mechanical rotational spectrum of freely rotating linear molecules by means of the Egelstaff transformation produces a symmetric spectrum whose first two even moments coincide with the corresponding classical moments.

  12. Dynamical Behaviour of a Modulated Torsion Pendulum in Test of Weak Equivalence Principle

    Institute of Scientific and Technical Information of China (English)

    YUE Ying; FAN Shu-Hua; LIU Lin-Xia; LUO Jun

    2005-01-01

    @@ The dynamic behaviour of a modulated torsion pendulum used to test the weak equivalence principle (WEP) is studied in detail. Theoretical analysis shows that the pendulum will be driven by a force with double-frequency of the rotating turntable no matter whether the WEP is valid or not. This double-frequency effect should be considered for improving the sensitivity of the modulated pendulum in test of the WEP.

  13. Generic behaviours in impact fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Sator, N.; Mechkov, S.; Sausset, F. [Paris-6 Univ. Pierre et Marie Curie, Lab. de Physique Theorique de la Matiere Condensee, UMR CNRS 7600, 75 - Paris (France); Mechkov, S. [Ecole Normale Superieure, Lab. de Physique Statistique, 75 - Paris (France)

    2008-02-15

    From atomic nuclei to supernovae, including plates and rocks, every cohesive system can be broken into fragments, provided that the deposited energy is sufficiently large compared to its cohesive energy. We present a simple numerical model for investigating the general properties of fragmentation. By use of molecular dynamics simulations, we study the impact fragmentation of a solid disk of interacting particles with a wall. Regardless of the particular form of the interaction potential, the fragment size distribution exhibits a power law behaviour with an exponent that increases logarithmically with the energy deposited in the system, in agreement with experiments. We expect this behaviour to be generic in fragmentation phenomena. (authors)

  14. Customer behaviour and student satisfaction

    Directory of Open Access Journals (Sweden)

    Enache, I. C.

    2011-01-01

    Full Text Available Having to overcome new challenges, the higher education institutions need to understand their customer behaviour. The students’ satisfaction is becoming an important objective for universities and society as the role of the tertiary level institution is being questioned. The aim of this paper is to provide a concrete marketing approach to the student satisfaction problem. The literature review section aims to present resources that deliver relevant and updated information about the marketing perspectives on student satisfaction. A short survey is developed in order to provide insights on student behaviour and student satisfaction.

  15. Hygienic food handling behaviours. An application of the Theory of Planned Behaviour.

    Science.gov (United States)

    Mullan, Barbara A; Wong, Cara L

    2009-06-01

    It is estimated that 5.4 million Australians get sick annually from eating contaminated food and that up to 20% of this illness results from food handling behaviour. A study was undertaken to investigate the efficacy of the Theory of Planned Behaviour (TPB) including past behaviour in predicting safe food handling intention and behaviour. One hundred and nine participants completed questionnaires regarding their attitudes, perceived behavioural control (PBC), subjective norm, intentions and past behaviour. Behaviour was measured 4 weeks later. The TPB predicted a high proportion of variance in both intentions and behaviour, and past behaviour/habit was found to be the strongest predictor of behaviour. The results of the present study suggest interventions aimed at increasing safe food handling intentions should focus on the impact of normative influences and perceptions of control over their food handling environment; whereas interventions to change actual behaviour should attempt to increase hygienic food handling as a habitual behaviour.

  16. Glycosaminoglycans of human rotator cuff tendons: changes with age and in chronic rotator cuff tendinitis.

    OpenAIRE

    Riley, G P; Harrall, R. L.; Constant, C R; Chard, M D; Cawston, T E; Hazleman, B L

    1994-01-01

    OBJECTIVES--To analyse the glycosaminoglycans of the adult human rotator cuff tendon matrix, to characterise changes in the glycosaminoglycan composition with age and in chronic rotator cuff tendinitis. METHODS--Rotator cuff (supraspinatus) tendons (n = 84) and common biceps tendons (n = 26) were obtained from cadavers with no history of tendon pathology (age range 11-95 years). Biopsies of rotator cuff tendons (supraspinatus and subscapularis tendons, n = 53) were obtained during open should...

  17. Theories of behaviour and behaviour change across the social and behavioural sciences: a scoping review.

    Science.gov (United States)

    Davis, Rachel; Campbell, Rona; Hildon, Zoe; Hobbs, Lorna; Michie, Susan

    2015-01-01

    Interventions to change health-related behaviours typically have modest effects and may be more effective if grounded in appropriate theory. Most theories applied to public health interventions tend to emphasise individual capabilities and motivation, with limited reference to context and social factors. Intervention effectiveness may be increased by drawing on a wider range of theories incorporating social, cultural and economic factors that influence behaviour. The primary aim of this paper is to identify theories of behaviour and behaviour change of potential relevance to public health interventions across four scientific disciplines: psychology, sociology, anthropology and economics. We report in detail the methodology of our scoping review used to identify these theories including which involved a systematic search of electronic databases, consultation with a multidisciplinary advisory group, web searching, searching of reference lists and hand searching of key behavioural science journals. Of secondary interest we developed a list of agreed criteria for judging the quality of the theories. We identified 82 theories and 9 criteria for assessing theory quality. The potential relevance of this wide-ranging number of theories to public health interventions and the ease and usefulness of evaluating the theories in terms of the quality criteria are however yet to be determined.

  18. Rotation in a reversed field pinch with active feedback stabilization of resistive wall modes

    Science.gov (United States)

    Cecconello, M.; Menmuir, S.; Brunsell, P. R.; Kuldkepp, M.

    2006-09-01

    Active feedback stabilization of multiple resistive wall modes (RWMs) has been successfully proven in the EXTRAP T2R reversed field pinch. One of the features of plasma discharges operated with active feedback stabilization, in addition to the prolongation of the plasma discharge, is the sustainment of the plasma rotation. Sustained rotation is observed both for the internally resonant tearing modes (TMs) and the intrinsic impurity oxygen ions. Good quantitative agreement between the toroidal rotation velocities of both is found: the toroidal rotation is characterized by an acceleration phase followed, after one wall time, by a deceleration phase that is slower than in standard discharges. The TMs and the impurity ions rotate in the same poloidal direction with also similar velocities. Poloidal and toroidal velocities have comparable amplitudes and a simple model of their radial profile reproduces the main features of the helical angular phase velocity. RWMs feedback does not qualitatively change the TMs behaviour and typical phenomena such as the dynamo and the 'slinky' are still observed. The improved sustainment of the plasma and TMs rotation occurs also when feedback only acts on internally non-resonant RWMs. This may be due to an indirect positive effect, through non-linear coupling between TMs and RWMs, of feedback on the TMs or to a reduced plasma-wall interaction affecting the plasma flow rotation. Electromagnetic torque calculations show that with active feedback stabilization the TMs amplitude remains well below the locking threshold condition for a thick shell. Finally, it is suggested that active feedback stabilization of RWMs and current profile control techniques can be employed simultaneously thus improving both the plasma duration and its confinement properties.

  19. Omni rotational driving and steering wheel

    DEFF Research Database (Denmark)

    2008-01-01

    omni rotational part (105) with a suspension (116) such that wheel part (108) can move relatively to the upper omni rotational part (105) in a suspension direction (118), and a reduction gear (120) for gearing the drive torque is provided in the wheel part (108) in order e.g. to assure traction...

  20. Polygons on a rotating fluid surface

    DEFF Research Database (Denmark)

    Jansson, Thomas R.N.; Haspang, Martin P.; Jensen, Kåre H.;

    2006-01-01

    rotating rigidly with a speed different from that of the plate. With water, we have observed polygons with up to 6 corners. It has been known for many years that such flows are prone to symmetry breaking, but apparently the polygonal surface shapes have never been observed. The creation of rotating...