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Sample records for sodium-water reaction phenomenon

  1. Theoretical Study of Sodium-Water Surface Reaction Mechanism

    NASA Astrophysics Data System (ADS)

    Kikuchi, Shin; Kurihara, Akikazu; Ohshima, Hiroyuki; Hashimoto, Kenro

    Computational study of the sodium-water reaction at the gas (water) - liquid (sodium) interface has been carried out using the ab initio (first-principle) method. A possible reaction channel has been identified for the stepwise OH bond dissociations of a single water molecule. The energetics including the binding energy of a water molecule on the sodium surface, the activation energies of the bond cleavages, and the reaction energies, have been evaluated, and the rate constants of the first and second OH bond-breakings have been compared. It was found that the estimated rate constant of the former was much larger than the latter. The results are the basis for constructing the chemical reaction model used in a multi-dimensional sodium-water reaction code, SERAPHIM, being developed by Japan Atomic Energy Agency (JAEA) toward the safety assessment of the steam generator (SG) in a sodium-cooled fast reactor (SFR).

  2. Dynamic effect of sodium-water reaction in fast flux test facility power addition sodium pipes

    SciTech Connect

    Huang, S.N.; Anderson, M.J.

    1990-03-01

    The Fast Flux Facility (FFTF) is a demonstration and test facility of the sodium-cooled fast breeder reactor. A power addition'' to the facility is being considered to convert some of the dumped, unused heat into electricity generation. Components and piping systems to be added are sodium-water steam generators, sodium loop extensions from existing dump heat exchangers to sodium-water steam generators, and conventional water/steam loops. The sodium loops can be subjected to the dynamic loadings of pressure pulses that are caused by postulated sodium leaks and subsequent sodium-water reaction in the steam generator. The existing FFTF secondary pipes and the new power addition sodium loops were evaluated for exposure to the dynamic effect of the sodium-water reaction. Elastic and simplified inelastic dynamic analyses were used in this feasibility study. The results indicate that both the maximum strain and strain range are within the allowable limits. Several cycles of the sodium-water reaction can be sustained by the sodium pipes that are supported by ordinary pipe supports and seismic restraints. Expensive axial pipe restraints to withstand the sodium-water reaction loads are not needed, because the pressure-pulse-induced alternating bending stresses act as secondary stresses and the pressure pulse dynamic effect is a deformation-controlled quantity and is self-limiting. 14 refs., 7 figs., 3 tabs.

  3. SWAAM-LT: The long-term, sodium/water reaction analysis method computer code

    SciTech Connect

    Shin, Y.W.; Chung, H.H.; Wiedermann, A.H.; Tanabe, H.

    1993-01-01

    The SWAAM-LT Code, developed for analysis of long-term effects of sodium/water reactions, is discussed. The theoretical formulation of the code is described, including the introduction of system matrices for ease of computer programming as a general system code. Also, some typical results of the code predictions for available large scale tests are presented. Test data for the steam generator design with the cover-gas feature and without the cover-gas feature are available and analyzed. The capabilities and limitations of the code are then discussed in light of the comparison between the code prediction and the test data.

  4. Microstructure and deformation mode of a stainless steel rupture disc exposed to sodium-water reaction

    SciTech Connect

    Sudha, C.; Parameswaran, P. Kishore, S.; Murthy, C. Meikanda; Rajan, M.; Vijayalakshmi, M.; Raghunathan, V.S.

    2008-08-15

    This paper deals with microstructural studies carried out on an austenitic stainless steel rupture disc which was exposed to sodium-water reaction. The rupture disc was part of a leak simulator put in a micro leak test section which was used to study the 'self wastage' of steam generator tubes. During micro leak testing, the rupture disc failed exhibiting a linear crack at a much lower pressure of 10 MPa rather than bursting open at the higher designed pressure of 15 MPa. The failed rupture disc revealed different microstructural features on the inner (steam exposed) and outer (sodium exposed) surfaces. Using microstructure as the signature, the temperature experienced by the rupture disc was predicted as {>=} 1273 K. Evidence for the exposure of the rupture disc to highly exothermic sodium-water reaction was obtained in the form of sodium rich debris, microcracks and deformation bands. Detailed transmission electron microscopy revealed the nature of deformation bands as deformation twins which is not a preferred failure mode for austenitic stainless steels.

  5. Response of rupture discs to sodium-water reaction pulses. Final report

    SciTech Connect

    Cagliostro, D.J.; Desmond, T.P.; Florence, A.L.

    1980-02-01

    A 1/7-scale model of a double rupture disc pressure relief device, designed for the intermediate heat transfer system of a liquid metal fast breeder reactor, was subjected to incident pressure pulses that simulated various sodium-water reaction pulses. General features of the pulses generated were an initial rise in pressure that lasted from 1 to 2 ms followed by a slow decrease in pressure that lasted for more than 50 ms. Pulses with nominal maximum pressures of 50, 100, 150, 200, 400, 600, and 800 psi were generated and transmitted along the pipe to load the rupture discs. The hydrostatic collapse pressure of the spherical cap of the rupture disc, determined by test in the same apparatus, was 250 psi. It is concluded that: (1) incident pressures must exceed half the static collapse pressure to cause rupture and so activate the relief system; and (2) incident pressures above the static collapse pressure result in reflected pressures that are less than the incident pressures.

  6. Sodium-water reaction acoustic noise for liquid phase injections. [LMFBR

    SciTech Connect

    Callis, K.R.; Greene, D.A.; Malovrh, J.W.

    1981-02-01

    Data on liquid and steam injections into sodium were recorded during a series of wastage experiments. These data are analyzed for acoustic power and spectral characteristics, expanding the data base up to 10 gm/sec injection rates from the earlier 0.5 gms/sec. No significant difference in acoustic power was measured between low temperature steam and liquid injections for the same mass flowrates. The bandwidth for steam injections is broader than for liquid injections. Reaction product deposition during water injections appears to cause a decrease in signal strength with test duration.

  7. Development of a multiphysics analysis system for sodium-water reaction phenomena in steam generators of sodium-cooled fast reactors

    NASA Astrophysics Data System (ADS)

    Uchibori, Akihiro; Kurihara, Akikazu; Ohshima, Hiroyuki

    2015-12-01

    A multiphysics analysis system for sodium-water reaction phenomena in a steam generator of sodium-cooled fast reactors was newly developed. The analysis system consists of the mechanistic numerical analysis codes, SERAPHIM, TACT, and RELAP5. The SERAPHIM code calculates the multicomponent multiphase flow and sodium-water chemical reaction caused by discharging of pressurized water vapor. Applicability of the SERAPHIM code was confirmed through the analyses of the experiment on water vapor discharging in liquid sodium. The TACT code was developed to calculate heat transfer from the reacting jet to the adjacent tube and to predict the tube failure occurrence. The numerical models integrated into the TACT code were verified through some related experiments. The RELAP5 code evaluates thermal hydraulic behavior of water inside the tube. The original heat transfer correlations were corrected for the tube rapidly heated by the reacting jet. The developed system enables evaluation of the wastage environment and the possibility of the failure propagation.

  8. Development of a multiphysics analysis system for sodium-water reaction phenomena in steam generators of sodium-cooled fast reactors

    SciTech Connect

    Uchibori, Akihiro; Kurihara, Akikazu; Ohshima, Hiroyuki

    2015-12-31

    A multiphysics analysis system for sodium-water reaction phenomena in a steam generator of sodium-cooled fast reactors was newly developed. The analysis system consists of the mechanistic numerical analysis codes, SERAPHIM, TACT, and RELAP5. The SERAPHIM code calculates the multicomponent multiphase flow and sodium-water chemical reaction caused by discharging of pressurized water vapor. Applicability of the SERAPHIM code was confirmed through the analyses of the experiment on water vapor discharging in liquid sodium. The TACT code was developed to calculate heat transfer from the reacting jet to the adjacent tube and to predict the tube failure occurrence. The numerical models integrated into the TACT code were verified through some related experiments. The RELAP5 code evaluates thermal hydraulic behavior of water inside the tube. The original heat transfer correlations were corrected for the tube rapidly heated by the reacting jet. The developed system enables evaluation of the wastage environment and the possibility of the failure propagation.

  9. Analysis of the dynamic response of a double rupture disc assembly to simulated sodium-water reaction pressure pulses

    SciTech Connect

    Leonard, J.R.

    1980-03-01

    A series of double rupture disc experiments were conducted in 1979 to evaluate the dynamic response characteristics of this pressure relief apparatus. The tests were performed in a facility with water simulating sodium and rising pressure pulses representative of the pressure increase resulting from a water/steam leak from a steam generator into sodium in the intermediate heat transport system of a breeder reactor power plant. Maximum source pressures ranged in magnitude from 50 psi to 800 psi. Dynamic response characteristics of each of the two rupture discs were similar to those observed in larger scale sodium-water experiments conducted in the Series I and Series II Large Leak Test Program at the Energy Technology Engineering Center. The SRI double rupture disc dynamic behavior was found to be consistent and amendable to modelling in the TRANSWRAP II computer code. A series of correlations which represent rupture disc buckling parameters were developed for use in the TRANSWRAP II code. The semi-empirical modeling of the rupture discs in the TRANSWRAP II code showed very good agreement with the experimental results.

  10. A new probe reaction for studying the hydrogen spillover phenomenon

    SciTech Connect

    Zhang, Aihua; Nakamura, Ikusei; Fujimoto, Kaoru

    1997-06-01

    It was found by FTIR measurement that pyridine strongly adsorbed on acid sites of ZSM-5 was hydrogenated over Pt/H-ZSM-5 (0.5 wt%) and a Pt-hybrid catalyst (a physically mixed catalyst with a weight ratio of Pt/SiO{sub 2} (2.5 wt%)/H-ZSM-5 = 1:4) to adsorbed piperidine in the presence of gaseous hydrogen at around 473 K, whereas no such phenomena were observed on either H-ZSM-5 or Pt/SiO{sub 2}. The phenomenon revealed the occurrence of hydrogen spillover from Pt sites to zeolite acid sites (Bronsted and Lewis). A quantitative description of this reaction was attained by calculating and measuring the amount of zeolite acid on the basis of pyridine chemisorption and hydrogen consumption. In connection with this finding, the dehydrogenation of adsorbed piperidine in correlation with reverse hydrogen spillover was also observed on Pt/H-ZSM-5 catalyst in the temperature range from 623 to 723 K. 29 refs., 9 figs., 1 tab.

  11. Analysis of large-leak test SWAT-3 Run-6 data by use of sodium-water-reaction analysis code SWAAM-I

    SciTech Connect

    Shin, Y.W.; Lin, H.C.

    1982-02-01

    The Sodium Water Advanced Analysis Method computer code (SWAAM-I) is used to analyze the large-leak test data SWAT-3 Run-6. The SWAT-3 is the mockup of the secondary system of the Japanese breeder-reactor demonstration plant Monju. The steam-generator design for the Monju reactor was a helical-coil-tube type with a cover-gas space, and the SWAT-3 Run-6 Test vessel simulates this design of the steam generator. The objectives of this work are: (1) to examine the adequacy of the SWAAM-I code for the helical-coil-tube steam-generator system, (2) to understand and confirm the understanding of phenomena that have major design implications, and (3) to define needs for additional development of SWAAM-I code capabilities.

  12. Lepra reaction with lucio phenomenon mimicking cutaneous vasculitis.

    PubMed

    Misra, Durga Prasanna; Parida, Jyoti Ranjan; Chowdhury, Abhra Chandra; Pani, Krushna Chandra; Kumari, Niraj; Krishnani, Narendra; Agarwal, Vikas

    2014-01-01

    Leprosy is a disease typically found in the tropics. Patients with leprosy can have varying presentation with constitutional symptoms, joint pains, skin nodules, and rarely a vasculitis-like picture with skin ulcers and neuropathy. We present a young lady who presented with the rare manifestation of skin infarcts mimicking cutaneous vasculitis, diagnosed on histopathology to have Lucio phenomenon on a background of lepromatous leprosy. With increasing migration and widespread use of biologic response modifiers, clinicians all over the world need to be aware of various presentations of leprosy as well as needing to keep an open mind while considering the differential diagnoses of vasculitis. PMID:25580317

  13. Lepra Reaction with Lucio Phenomenon Mimicking Cutaneous Vasculitis

    PubMed Central

    Misra, Durga Prasanna; Parida, Jyoti Ranjan; Chowdhury, Abhra Chandra; Pani, Krushna Chandra; Kumari, Niraj; Krishnani, Narendra

    2014-01-01

    Leprosy is a disease typically found in the tropics. Patients with leprosy can have varying presentation with constitutional symptoms, joint pains, skin nodules, and rarely a vasculitis-like picture with skin ulcers and neuropathy. We present a young lady who presented with the rare manifestation of skin infarcts mimicking cutaneous vasculitis, diagnosed on histopathology to have Lucio phenomenon on a background of lepromatous leprosy. With increasing migration and widespread use of biologic response modifiers, clinicians all over the world need to be aware of various presentations of leprosy as well as needing to keep an open mind while considering the differential diagnoses of vasculitis. PMID:25580317

  14. Reaction Current Phenomenon in Bifunctional Catalytic Metal-Semiconductor Nanostructures

    NASA Astrophysics Data System (ADS)

    Hashemian, Mohammad Amin

    Energy transfer processes accompany every elementary step of catalytic chemical processes on material surface including molecular adsorption and dissociation on atoms, interactions between intermediates, and desorption of reaction products from the catalyst surface. Therefore, detailed understanding of these processes on the molecular level is of great fundamental and practical interest in energy-related applications of nanomaterials. Two main mechanisms of energy transfer from adsorbed particles to a surface are known: (i) adiabatic via excitation of quantized lattice vibrations (phonons) and (ii) non-adiabatic via electronic excitations (electron/hole pairs). Electronic excitations play a key role in nanocatalysis, and it was recently shown that they can be efficiently detected and studied using Schottky-type catalytic nanostructures in the form of measureable electrical currents (chemicurrents) in an external electrical circuit. These nanostructures typically contain an electrically continuous nanocathode layers made of a catalytic metal deposited on a semiconductor substrate. The goal of this research is to study the direct observations of hot electron currents (chemicurrents) in catalytic Schottky structures, using a continuous mesh-like Pt nanofilm grown onto a mesoporous TiO2 substrate. Such devices showed qualitatively different and more diverse signal properties, compared to the earlier devices using smooth substrates, which could only be explained on the basis of bifunctionality. In particular, it was necessary to suggest that different stages of the reaction are occurring on both phases of the catalytic structure. Analysis of the signal behavior also led to discovery of a formerly unknown (very slow) mode of the oxyhydrogen reaction on the Pt/TiO2(por) system occurring at room temperature. This slow mode was producing surprisingly large stationary chemicurrents in the range 10--50 microA/cm2. Results of the chemicurrent measurements for the bifunctional

  15. Tournay's description of anisocoria on lateral gaze: reaction, myth, or phenomenon?

    PubMed

    Robert, Matthieu P; Plant, Gordon T

    2014-02-01

    The year 1917 witnessed the opening of a great debate in neuro-ophthalmology, with Tournay's description of a phenomenon thought to be universal: anisocoria in lateral gaze, due to mydriasis of the abducting pupil and a minor miosis of the fellow one. Through many publications, this phenomenon was soon assessed and confirmed to be physiologic, while the cause of the pupil reaction in lateral gaze was extensively discussed. Cases of abolition and reversal of the phenomenon were also reported in specific clinical situations, such as neurosyphilis, and its study became part of the neuro-ophthalmologic examination. Publications on the phenomenon declined after 1934, with only one publication appearing between 1934 and 1974 (1957). In 1974, the demise of the Tournay phenomenon was secured after 2 pupillographic studies showed it to be rare and marginal. This story is reviewed. Hypotheses are proposed in order to help unfold the controversy; anisocoria in lateral gaze should not be regarded as a myth, nor does it--or only rarely--correspond to a pupil reaction, or noumenon: it can usually be accounted for by a specific optical distortion (apparent without real anisocoria) and hence fits the Kantian definition of a phenomenon. An understanding of Tournay phenomenon is therefore of current relevance to the examination of the pupils to avoid misinterpretation of observed changes in the pupil. PMID:24491971

  16. [Persistent skin reaction and Raynaud phenomenon after a sting by Echiichthys draco (great weever fish)].

    PubMed

    Mayser, P; Dreyer, F; Repp, H

    2003-07-01

    A 54-year-old recreational angler was stung in his right forefinger by Echiichthys draco. Within a few seconds he developed severe swelling with extreme pain sensation at the sting site, accompanied by dizziness and chill. Even under morphine therapy the pain symptoms were only slightly reduced. During the subsequent weeks, an erythema with marginate medium-sized scaling developed at the sting site and the patient experienced a approximately 50% reduced bending capacity of the forefinger and permanent numbness in this region. After 4 months, Raynaud phenomenon developed limited to the right forefinger. Great weever fishes (Echiichthys spp.) are the most venomous fishes in European waters. In humans, life-threatening sting reactions occur only in exceptional cases. As a commercial antiserum is not available, the therapy is mainly empiric (General measures of first aid and emergency medicine, the wound should be thoroughly washed). Patients should be informed that reduced motion ability, swelling or Raynaud's phenomenon can persist for several months. PMID:12835865

  17. Medical Students' Reactions to Anatomic Dissection and the Phenomenon of Cadaver Naming

    ERIC Educational Resources Information Center

    Williams, Austin D.; Greenwald, Emily E.; Soricelli, Rhonda L.; DePace, Dennis M.

    2014-01-01

    The teaching of gross anatomy has, for centuries, relied on the dissection of human cadavers, and this formative experience is known to evoke strong emotional responses. The authors hypothesized that the phenomenon of cadaver naming is a coping mechanism used by medical students and that it correlates with other attitudes about dissection and body…

  18. Medical students' reactions to anatomic dissection and the phenomenon of cadaver naming.

    PubMed

    Williams, Austin D; Greenwald, Emily E; Soricelli, Rhonda L; DePace, Dennis M

    2014-01-01

    The teaching of gross anatomy has, for centuries, relied on the dissection of human cadavers, and this formative experience is known to evoke strong emotional responses. The authors hypothesized that the phenomenon of cadaver naming is a coping mechanism used by medical students and that it correlates with other attitudes about dissection and body donation. The authors developed a 33-question electronic survey to which 1,156 medical students at 12 medical schools in the United States voluntarily responded (November 2011-March 2012). They also surveyed course directors from each institution regarding their curricula and their observations of students' coping mechanisms. The majority of students (574, 67.8%) named their cadaver. Students most commonly cited the cadaver's age as the reason they chose a particular name for the cadaver. A minority of the students who did not name the cadaver reported finding the practice of naming disrespectful. Almost all students indicated that they would have liked to know more about their donor, particularly his or her medical history. Finally, students who knew the birth name of the donor used it less frequently than predicted. The authors found that the practice of naming cadavers is extremely prevalent among medical students and that inventive naming serves as a beneficial coping mechanism. The authors suggest that developing a method of providing students with more information about their cadaver while protecting the anonymity of the donor and family would be useful. PMID:23913911

  19. Raynaud's Phenomenon

    MedlinePlus

    ... toes) constrict (narrow), usually in response to cold temperatures and/or emotional stress. When this condition occurs ... be an exaggeration of normal responses to cold temperature and/or stress. When Raynaud’s phenomenon is caused ...

  20. Raynaud phenomenon

    MedlinePlus

    Taking these steps may help control Raynaud phenomenon: Keep the body warm. Avoid exposure to cold in any form. Wear mittens or gloves outdoors and when handling ice or frozen food. Avoid getting chilled, which may ...

  1. Role of water in the chlorine evolution reaction at RuO(2)-based electrodes--understanding electrocatalysis as a resonance phenomenon.

    PubMed

    Zeradjanin, Aleksandar R; Menzel, Nadine; Strasser, Peter; Schuhmann, Wolfgang

    2012-10-01

    The reaction path of the Cl(2) evolution reaction (CER) was investigated by combining electrochemical and spectroscopic methods. It is shown that oxidation and reconstruction of the catalyst surface during CER is a consequence of the interaction between RuO(2) and water. The state of the RuO(2) surface during the electrochemical reaction was analyzed in situ by using Raman spectroscopy to monitor vibrations of the crystal lattice of RuO(2) and changes in the surface concentration of the adsorbed species as a function of the electrode potential. The role of the solvent was recognized as being crucial in the formation of an oxygen-containing hydrophilic layer, which is a key prerequisite for electrocatalytic Cl(2) formation. Water (more precisely the OH adlayer) is understood not just as a medium that allows adsorption of intermediates, but also as an integral part of the intermediate formed during the electrochemical reaction. New insights into the general understanding of electrocatalysis were obtained by utilizing the vibration frequencies of the crystal lattice as a dynamic catalytic descriptor instead of thermodynamic descriptors, such as the adsorption energy of intermediates. Interpretation of the derived "volcano" curve suggests that electrocatalysis is governed by a resonance phenomenon. PMID:22893626

  2. An unusual phenomenon of surface reaction observed during Ge overgrowth on Mn5Ge3/Ge(111) heterostructures

    NASA Astrophysics Data System (ADS)

    Dau, Minh-Tuan; Le Thanh, Vinh; Michez, Lisa A.; Petit, Matthieu; Le, Thi-Giang; Abbes, Omar; Spiesser, Aurélie; Ranguis, Alain

    2012-10-01

    The Mn5Ge3 compound, thanks to its room-temperature ferromagnetism, metallic character and ability to epitaxially grow on germanium, acts as a potential candidate for spin injection into group-IV semiconductors. Understanding and controlling Ge overgrowth behaviour on Mn5Ge3/Ge heterostructures represents a crucial step to realize Ge/Mn5Ge3/Ge multilayers for numerous spintronic applications. Here, we have combined structural and morphological characterizations with magnetic analyses to study the mechanisms of Ge overgrowth on epitaxial Mn5Ge3 layers in the temperature range of 450-550 °C. It is found that deposited Ge instantly reacts with Mn to form a Mn5Ge3 surface layer, which, acting as a surfactant, continuously floats upwards from the growing surface to a distance larger than 70 nm. New Ge layers are successively formed underneath, allowing such a floating Mn5Ge3 surface layer to be stabilized by epitaxy. These observations can be considered as a typical example in which the stabilization of metastable thin films by epitaxy can overcome thermodynamic equilibrium. We have also investigated the effect of carbon adsorption on the top of the Mn5Ge3 layer prior to Ge deposition to control the Mn:Ge reaction. It is shown that adsorbed carbon effectively reduces the out-diffusion of Mn from Mn5Ge3, allowing Ge layers to stack up on top of Mn5Ge3. However, at temperatures of 450-550 °C, carbon may react with Mn to form manganese carbides and the resulting Ge overlayers are found to change their orientation from the (111) plane to the (001) plane, which has a higher surface energy. Finally, a strategy to realize Ge/Mn5Ge3/Ge multilayers will be addressed.

  3. Vacuum phenomenon.

    PubMed

    Yanagawa, Youichi; Ohsaka, Hiromichi; Jitsuiki, Kei; Yoshizawa, Toshihiko; Takeuchi, Ikuto; Omori, Kazuhiko; Oode, Yasumasa; Ishikawa, Kouhei

    2016-08-01

    This article describes the theory of the formation of the vacuum phenomenon (VP), the detection of the VP, the different medical causes, the different locations of the presentation of the VP, and the differential diagnoses. In the human body, the cavitation effect is recognized on radiological studies; it is called the VP. The mechanism responsible for the formation of the VP is as follows: if an enclosed tissue space is allowed to expand as a rebound phenomenon after an external impact, the volume within the enclosed space will increase. In the setting of expanding volume, the pressure within the space will decrease. The solubility of the gas in the enclosed space will decrease as the pressure of the space decreases. Decreased solubility allows a gas to leave a solution. Clinically, the pathologies associated with the VP have been reported to mainly include the normal joint motion, degeneration of the intervertebral discs or joints, and trauma. The frequent use of CT for trauma patients and the high spatial resolution of CT images might produce the greatest number of chances to detect the VP in trauma patients. The VP is observed at locations that experience a traumatic impact; thus, an analysis of the VP may be useful for elucidating the mechanism of an injury. When the VP is located in the abdomen, it is important to include perforation of the digestive tract in the differential diagnosis. The presence of the VP in trauma patients does not itself influence the final outcome. PMID:27147527

  4. Raynaud's phenomenon.

    PubMed

    Hughes, Michael; Herrick, Ariane L

    2016-02-01

    Raynaud's phenomenon (RP) is a major cause of pain and disability in patients with autoimmune connective tissue diseases (CTDs), particularly systemic sclerosis (SSc). The clinician must perform a comprehensive clinical assessment in patients with RP to differentiate between primary (idiopathic) and secondary RP, in particular (for rheumatologists), secondary to an autoimmune CTD, as both the prognosis and treatment may differ significantly. Key investigations are nailfold capillaroscopy and testing for autoantibodies (in particular, those associated with SSc). Patients with RP and either abnormal nailfold capillaroscopy or an SSc-specific antibody (and especially with both) have a high risk of transitioning to an autoimmune CTD. Both nailfold capillaroscopy and autoantibody specificity may help the clinician in predicting organ-based complications. The management of CTD-associated RP requires a multifaceted approach to treatment, including patient education and conservative ('non-drug') measures. Patients with CTD-associated RP often require pharmacological treatment, which in the first instance is usually a calcium channel blocker, although other agents can be used. There is an increasing tendency to use phosphodiesterase type 5 inhibitors early in the treatment of CTD-associated RP. Oral therapies are commonly associated with side effects (often due to systemic vasodilation) that may result in failure of dose escalation and/or permanent discontinuation. Intravenous prostanoid therapy and surgery (e.g., botulinum toxin injection and digital sympathectomy) can be considered in severe RP. Patients with CTD-associated RP can develop a number of ischaemic digital complications (primarily ulcers and critical ischaemia), which may be associated with significant tissue loss. Future research is required to increase the understanding of the pathogenesis and natural history of RP (to drive therapeutic advances), and to explore/develop drug therapies, including those that

  5. Amplified-response-spectrum analysis of sodium-water reaction pressure waves. [LMFBR

    SciTech Connect

    Knittle, D.E.

    1981-10-28

    This report deals with a frequency spectrum evaluation of the SWAAM I predicted double rupture disc assembly operation pressure wave generated in the LLTR Series II A-2 test. It also evaluates the same wave predicted by the TRANSWRAP II code and the pressure wave actually measured upstream of the rupture disc assembly by the test instrumentation in Test A-2. The SWAAM I and TRANSWRAP II codes currently use the same analytical model to characterize the rupture disc until the disc strikes the knife edges. Thereafter, the SWAAM I code relies on analytical techniques to characterize the phenomena, whereas the TRANSWRAP II code uses empirical parameters based on A-2 test data to represent the disc behavior. Any differences in the predicted dynamic pipe loads caused by double rupture disc assembly operation, using the forcing functions predicted by the codes can, therefore, be traced to this difference.

  6. What Is Raynaud's Phenomenon?

    MedlinePlus

    ... Phenomenon PDF Version Size: 59 KB November 2014 What Is Raynaud’s Phenomenon? Fast Facts: An Easy-to- ... use tools that vibrate, such as a jackhammer. What Are the Symptoms of Raynaud’s Phenomenon? The body ...

  7. Regional Acceleratory Phenomenon.

    PubMed

    Verna, Carlalberta

    2016-01-01

    The regional acceleratory phenomenon (RAP) is a tissue reaction to a noxious stimulus that increases the healing capacities of the affected tissues. It is typical not only of hard tissues such as bone and cartilage, but also of soft tissues. The RAP is characterized by acceleration of the normal cellular activities, as an 'SOS' phenomenon of the body that has to respond to the new perturbation. In the alveolar bone, the RAP is characterized, at a cellular level, by increased activation of the basic multicellular units (BMUs), thereby increasing the remodeling space. At the tissue level, the RAP is characterized by the production of woven bone, with the typical unorganized pattern, that will be reorganized into lamellar bone at a later stage. In the alveolar bone, the RAP occurs typically in the healing process of the alveolar sockets after tooth extraction, in periodontal disease, after surgery and trauma and during orthodontic tooth movement. In relation to orthodontic tooth movement, the RAP can be seen as a tissue response to the mechanical cyclical perturbation that induces the formation of microdamage that has to be removed to avoid their accumulation and the following bone failure. The adaptation to the new orthodontically induced mechanical environment is ensured by an increased activation of the BMU that returns to normal levels after few months. PMID:26599115

  8. The Root Pressure Phenomenon

    ERIC Educational Resources Information Center

    Marsh, A. R.

    1972-01-01

    Describes experiments demonstrating that root pressure in plants is probably controlled by a circadian rhythm (biological clock). Root pressure phenomenon plays significant part in water transport in contradiction with prevalent belief. (PS)

  9. What Is Raynaud's Phenomenon?

    MedlinePlus

    ... diagnose which form it is using a complete history, an exam, and tests. Tests may include:  Blood tests.  Looking at fingernail tissue with a microscope. What Is the Treatment for Raynaud’s Phenomenon? Treatment ...

  10. The Lazarus phenomenon.

    PubMed

    Sahni, Vaibhav

    2016-08-01

    The Lazarus phenomenon or the unassisted return of spontaneous circulation after cardiac arrest is a grossly underreported phenomenon in medical literature which essentially implies the 'resurrection' of an individual after cardiac arrest. Although there have been a handful of such cases reported, the clinical incidence and significance may be underestimated. Because of the presumed infrequency of this condition, there are no studies specifically researching Lazarus phenomenon in scientific literature. This review intends to systematically present current and past knowledge on this rare but definitive phenomenon. Research databases namely Google Scholar, Science Direct, Medline and PubMed were utilized. Only articles which identified cases where the return of spontaneous circulation occurred after cessation of Cardiopulmonary Resuscitation (CPR), and review articles on the entity were included. The mentioned databases were searched using the terms 'Lazarus phenomenon', 'cardiopulmonary resuscitation' and 'return of spontaneous circulation'. A literature review was synthesised based on articles meeting the eligibility criteria to better understand the phenomenon of return of spontaneous circulation. PMID:27540490

  11. AIDS as a social phenomenon.

    PubMed

    Bennett, F J

    1987-01-01

    AIDS as a new lethal and at present incurable sexually transmitted disease is already having remarkable social repercussions not yet fully explicit and hence it can be termed a social phenomenon. Political, behavioural, economic and legal reactions and social responses such as stigmatization, changes in the sick role and the growth of voluntary organizations and international collaboration are described. Communication, education and information aspects of AIDS are considered using material from the press and it is clear that a massive educational approach to modify behaviour must be the basis for a control programme. PMID:3317877

  12. The Lazarus phenomenon

    PubMed Central

    2016-01-01

    The Lazarus phenomenon or the unassisted return of spontaneous circulation after cardiac arrest is a grossly underreported phenomenon in medical literature which essentially implies the ‘resurrection’ of an individual after cardiac arrest. Although there have been a handful of such cases reported, the clinical incidence and significance may be underestimated. Because of the presumed infrequency of this condition, there are no studies specifically researching Lazarus phenomenon in scientific literature. This review intends to systematically present current and past knowledge on this rare but definitive phenomenon. Research databases namely Google Scholar, Science Direct, Medline and PubMed were utilized. Only articles which identified cases where the return of spontaneous circulation occurred after cessation of Cardiopulmonary Resuscitation (CPR), and review articles on the entity were included. The mentioned databases were searched using the terms ‘Lazarus phenomenon’, ‘cardiopulmonary resuscitation’ and ‘return of spontaneous circulation’. A literature review was synthesised based on articles meeting the eligibility criteria to better understand the phenomenon of return of spontaneous circulation. PMID:27540490

  13. [Arteriography in Raynaud's phenomenon].

    PubMed

    Reggi, M; Monin, A; Courbier, R

    1986-01-01

    Bilateral angiographic examination of the upper limbs is performed under general anesthesia in 64 patients of a group of 138 Raynaud's phenomenons. Clinical severity of the Raynaud's phenomenon is evaluated according to the 3 grades of Porter's classification but including a grade 4 corresponding to digital gangrene. Aetiology of Raynaud's phenomenon is in relation with connective tissue diseases in 11 cases and with other aetiologies in 22 cases. Aetiology is not defined in 31 cases. Angiographic findings are: Arterial lesions are present in all 64 patients, including 11 cases of "Raynaud's disease" defined by clinical and capillaroscopic signs. Frequency of the forearm artery lesions (31% of patients), a majority concerning ulnar artery. Absence of palmar anastomosis in 55% of the cases. Frequency and severity of digital (mean 1.4/hand) and collateral digital (mean: 7.4/hand) artery lesions. Arterial lesions are in relation with the clinical severity of the Raynaud's phenomenon but generally not with its aetiology. Authors consider that angiographic examination may be indicated in Raynaud's phenomenons in relation with defined aetiology but generally not in the other cases. PMID:3944525

  14. The American compensation phenomenon.

    PubMed

    Bale, A

    1990-01-01

    In this article, the author defines the occupational safety and health domain, characterizes the distinct compensation phenomenon in the United States, and briefly reviews important developments in the last decade involving Karen Silkwood, intentional torts, and asbestos litigation. He examines the class conflict over the value and meaning of work-related injuries and illnesses involved in the practical activity of making claims and turning them into money through compensation inquiries. Juries, attributions of fault, and medicolegal discourse play key roles in the compensation phenomenon. This article demonstrates the extensive, probing inquiry through workers' bodies constituted by the American compensation phenomenon into the moral basis of elements of the system of production. PMID:2139638

  15. The whistler nozzle phenomenon

    NASA Technical Reports Server (NTRS)

    Hussain, A. K. M. F.; Hasan, M. A. Z.

    1982-01-01

    The whistler nozzle is a simple device which can induce jet self-excitations of controllable amplitudes and frequencies and appears highly promising for many applications involving turbulent transport, combustion and aerodynamic noise. The characteristics of this curious phenomenon are documented for different values of the controlling parameters and attempts to explain the phenomenon. It is shown that the whistler excitation results from the coupling of two independent resonance mechanisms: shear-layer tone resulting from the impingement of the pipe-exit shear layer on the collar lip, and organ-pipe resonance of the pipe-nozzle. The crucial role of the shear-layer tone in driving the organ-pipe resonance is proven by reproducing the event in pipe-ring and pipe-hole configurations in the absence of the collar. It is also shown that this phenomenon is the strongest when the self-excitation frequency matches the preferred mode of the jet.

  16. The Leidenfrost Phenomenon

    ERIC Educational Resources Information Center

    Curzon, F. L.

    1978-01-01

    Describes four demonstrations of the Leidenfrost phenomenon; floating of liquid drops on their own vapor above a hot surface, delayed quenching of red-hot brass by water, explosion of vessels containing suspended liquid droplets, and momentary incombustibility of living tissue immersed in boiling oil. (Author/GA)

  17. The exploding wire phenomenon

    NASA Astrophysics Data System (ADS)

    Aspden, H.

    1985-02-01

    Graneau's recent interpretation of the exploding wire phenomenon as an electrodynamic effect verifying Ampère's classical formulation is questioned. Instead, it is shown that the rupturing force arising from the imbalance of the self-induced electromotive force and the ohmic potential during an explosive current surge will account for the wire breaking into several segments, as is observed.

  18. [Lazarus phenomenon: spontaneous resuscitation].

    PubMed

    Casielles García, J L; González Latorre, M V; Fernández Amigo, N; Guerra Vélz, A; Cotta Galán, M; Bravo Capaz, E; de las Mulas Béjar, M

    2004-01-01

    A 94-year-old woman undergoing surgery for simple repair of a duodenal perforation experienced a sudden massive hemorrhage (1500 mL) when the duodenum was separated from adjacent structures. Hemodynamic stability was re-established when fluids were replaced. After the abdominal wall was closed, increased amplitude of the QRS wave was observed and heart rate slowed until there was no pulse. Electromechanical dissociation (EMD) was diagnosed and cardiopulmonary resuscitation was started. When EMD persisted after 40 minutes, resuscitative measures were stopped and the ventilator was disconnected, though orotracheal intubation and arterial and electrocardiographic monitoring were maintained. After 2 or 3 minutes, heart rhythm restarted spontaneously and arterial pressure waves reappeared on the monitor. The patient progressed well for 72 hours, after which she developed septic shock and multiorgan failure, dying 18 days later. The Lazarus phenomenon may be more common than the medical literature would indicate, possibly because a large gap in our understanding of the pathophysiology of the phenomenon underlies anecdotes about "miracles". As we wait for adequate international consensus on a protocol for monitoring the withdrawal of resuscitative measures, we should act prudently before definitively certifying death. The case we report occurred during a surgical intervention in which the patient had received general anesthesia. We believe that the causes that might explain the Lazarus phenomenon are quite different in that context than they would be in a nonsurgical setting, such that it would be useful to create a national database to keep a record of such intraoperative events. PMID:15495638

  19. Prebiotic homochirality as a critical phenomenon.

    PubMed

    Gleiser, Marcelo; Thorarinson, Joel

    2006-12-01

    The development of prebiotic homochirality on early-Earth or another planetary platform may be viewed as a critical phenomenon. It is shown, in the context of spatio-temporal polymerization reaction networks, that environmental effects--be they temperature surges or other external disruptions--may destroy any net chirality previously produced. In order to understand the emergence of prebiotic homochirality it is important to model the coupling of polymerization reaction networks to different planetary environments. PMID:17120129

  20. Translation as a psycholinguistic phenomenon.

    PubMed

    Zasyekin, Serhiy

    2010-06-01

    The article sketches the outlines of a theoretical framework for the analysis of translation of literary texts, viewed as psycho-semiotic phenomenon and based on evaluation of earlier attempts in this direction, and on the results of a psycholinguistic empirical study of translations. Central to this framework is the recent insight that the human cerebral hemisphere functional asymmetry somehow plays a role in structuring the fictional text by its author and in its processing by the interpreter. It is argued that the texts of modernism and post-modernism contain information blocks describing a character's perception of events in altered states of consciousness. This model helps to explain how a translator's inappropriate linguistic choice may influence the target language reader's aesthetic reaction. PMID:19894118

  1. The charge transfer transition phenomenon and microstructure of Eu{sup 3+}-doped NaCaPO{sub 4} phosphors sintered with NH{sub 4}Cl flux via solid-state reaction

    SciTech Connect

    Peng, Yu-Ming; Su, Yan-Kuin; Yang, Ru-Yuan

    2013-05-15

    Graphical abstract: This paper describes: The charge transfer transition phenomenon and microstructure of Eu{sup 3+}-doped NaCaPO{sub 4} phosphors sintered with NH{sub 4}Cl flux via solid-state reaction. The emission intensity of NaCa{sub 0.95}PO{sub 4}:0.05Eu{sup 3+} phosphors with 2 wt.% NH{sub 4}Cl flux is enhanced as the sintering temperature was increased from 800 °C to 1000 °C and reveals the maximum value at 1000 °C. Photoluminescence emission spectra of NaCa{sub 0.95}PO{sub 4}:0.05Eu{sup 3+} phosphors with 2 wt.% NH{sub 4}Cl flux sintered at various sintering temperature for 3 h via solid state reaction method (λ{sub ex} = 270 nm). Highlights: ► NH{sub 4}Cl flux is helpful for enhancing the crystallization degree and decreasing surface defects. ► A single phase of NaCaPO{sub 4}:Eu{sup 3+} phosphor was observed as the sintering temperature was increased from 800 °C to 1000 °C. ► The intensity of the excitation peaks displays a maximum value at 1000 °C. ► The NaCaPO{sub 4} host added with NH{sub 4}Cl flux and sintered at the different temperature can affect the morphology. ► The NaCaPO{sub 4} host added with NH{sub 4}Cl flux and sintered at the different temperature can affect fluorescent properties. - Abstract: NaCa{sub 0.95}PO{sub 4}:0.05Eu{sup 3+} phosphors with 2 wt.% NH{sub 4}Cl flux sintered at various sintering temperature (800, 900, 1000, 1100 °C) for 3 h under air atmosphere were synthesized successfully via solid state reaction method. It is found that the addition of NH{sub 4}Cl flux and different sintering temperatures can affect the morphology and fluorescent properties of NaCa{sub 0.95}PO{sub 4}:0.05Eu{sup 3+} phosphor. The X-ray diffractions show a single phase and the microstructure observations show uniform morphologies for NaCa{sub 0.95}PO{sub 4}:0.05Eu{sup 3+} phosphors sintered at the range from 900 °C to 1000 °C, indicating that addition of 2 wt.% NH{sub 4}Cl flux is helpful for enhancing the crystallization, thus

  2. Winter Cardiovascular Diseases Phenomenon

    PubMed Central

    Fares, Auda

    2013-01-01

    This paper review seasonal patterns across twelve cardiovascular diseases: Deep venous thrombosis, pulmonary embolism, aortic dissection and rupture, stroke, intracerebral hemorrhage, hypertension, heart failure, angina pectoris, myocardial infarction, sudden cardiac death, venricular arrythmia and atrial fibrillation, and discuss a possible cause of the occurrence of these diseases. There is a clear seasonal trend of cardiovascular diseases, with the highest incidence occurring during the colder winter months, which have been described in many countries. This phenomenon likely contributes to the numbers of deaths occurring in winter. The implications of this finding are important for testing the relative importance of the proposed mechanisms. Understanding the influence of season and other factors is essential when seeking to implement effective public health measures. PMID:23724401

  3. The neutron channeling phenomenon.

    PubMed

    Khanouchi, A; Sabir, A; Boulkheir, M; Ichaoui, R; Ghassoun, J; Jehouani, A

    1997-01-01

    Shields, used for protection against radiation, are often pierced with vacuum channels for passing cables and other instruments for measurements. The neutron transmission through these shields is an unavoidable phenomenon. In this work we study and discuss the effect of channels on neutron transmission through shields. We consider an infinite homogeneous slab, with a fixed thickness (20 lambda, with lambda the mean free path of the neutron in the slab), which contains a vacuum channel. This slab is irradiated with an infinite source of neutrons on the left side and on the other side (right side) many detectors with windows equal to 2 lambda are placed in order to evaluate the neutron transmission probabilities (Khanouchi, A., Aboubekr, A., Ghassoun, J. and Jehouani, A. (1994) Rencontre Nationale des Jeunes Chercheurs en Physique. Casa Blanca Maroc; Khanouchi, A., Sabir, A., Ghassoun, J. and Jehouani, A. (1995) Premier Congré International des Intéractions Rayonnements Matière. Eljadida Maroc). The neutron history within the slab is simulated by the Monte Carlo method (Booth, T. E. and Hendricks, J. S. (1994) Nuclear Technology 5) and using the exponential biasing technique in order to improve the Monte Carlo calculation (Levitt, L. B. (1968) Nuclear Science and Engineering 31, 500-504; Jehouani, A., Ghassoun, J. and Aboubker, A. (1994) In Proceedings of the 6th International Symposium on Radiation Physics, Rabat, Morocco). Then different geometries of the vacuum channel have been studied. For each geometry we have determined the detector response and calculated the neutron transmission probability for different detector positions. This neutron transmission probability presents a peak for the detectors placed in front of the vacuum channel. This study allowed us to clearly identify the neutron channeling phenomenon. One application of our study is to detect vacuum defects in materials. PMID:9463884

  4. The two-woman phenomenon.

    PubMed

    Weiss, S S

    1987-04-01

    A distinct type of phenomenon that has not been previously noted as such is named and described. Men who present a two-woman phenomenon retain a commitment to wife and marriage while loving another woman. Conflict arises only when one of the women has to be relinquished. It is postulated that many men with this pattern of loving have experienced a traumatic childhood and an oedipal conflict which defensively involved two maternal objects in fantasy or reality. One mother was hated, the other loved. This dynamic is one possible determinant leading to the two-woman phenomenon. PMID:3588786

  5. Aloneness and the Isakower phenomenon.

    PubMed

    Peterson, C A

    1992-01-01

    Under the sway of the oedipal imperative, the Isakower phenomenon has long been regarded as a regressive perceptual defense against castration anxiety accompanying incestuous wishes, often stimulated by primal scene exposure-fantasy. Clinical material from the psychoanalytic psychotherapy of a borderline patient with object constancy deficits is offered to support a reconceptualization of the Isakower phenomenon: Following annihilatory rage and the destruction of extant inner objects, resulting in a regression to the "drive organization of memory," the face-breast imagery within the Isakower phenomenon arrives as a hallucinatory alternative to unbearable aloneness. PMID:1607306

  6. The phenomenon of fluorescence in immunosensors.

    PubMed

    Kłos-Witkowska, Aleksandra

    2016-01-01

    The phenomenon of fluorescence in immunosensors is described in this paper. Both structure and characteristics of biosensors and immunosensors are presented. Types of immunosensors and the response of bioreceptor layers to the reaction with analytes as well as measurements of electrochemical, piezoelectric and optical parameters in immunosensors are also presented. In addition, detection techniques used in studies of optical immunosensors based on light-matter interactions (absorbance, reflectance, dispersion, emission) such as: UV/VIS spectroscopy, reflectometric interference spectroscopy (RIfs), surface plasmon resonance (SPR), optical waveguide light-mode spectroscopy (OWLS), fluorescence spectroscopy. The phenomenon of fluorescence in immunosensors and standard configurations of immunoreactions between an antigen and an antibody (direct, competitive, sandwich, displacement) is described. Fluorescence parameters taken into account in analyses and fluorescence detection techniques used in research of immunosensors are presented. Examples of immunosensor applications are given. PMID:27192088

  7. [Methylphenidate and secondary Raynaud's phenomenon].

    PubMed

    Iglesias Otero, M; Portela Romero, M; Bugarín González, R; Ventura Victoria, M A

    2013-09-01

    Raynaud's phenomenon is a clinical disease characterized by episodic attacks of vasoconstriction of the arteries and arterioles of the extremities such as fingers and toes, sometimes the ears and nose, in response to cold or emotional stimuli. A classic attack is the pallor of the distal extremity, followed by cyanosis and redness, accompanied by paresthesia, usually as heat. When it occurs without apparent cause is called primary Raynaud's phenomenon. When associated with other disease, is called secondary Raynaud's phenomenon. The secondary table is associated with increased frequency of rheumatic diseases of collagen. They can also present certain drugs that cause vasoconstriction, such as ergotamine, beta-adrenergic antagonists, contraception and sympathomimetic drugs. Regarding the latter, we present a case of Raynaud's phenomenon secondary to methylphenidate in a 14 years. PMID:24034762

  8. Koebner Phenomenon and Mycosis Fungoides

    PubMed Central

    Lebas, Eve; Libon, Florence; Nikkels, Arjen F.

    2015-01-01

    Mycosis fungoides (MF) is the most frequent type of primary cutaneous T-cell/NK-cell lymphoma. The Koebner phenomenon is defined as the appearance of cutaneous lesions on previously noninvolved skin following trauma and is observed in a series of cutaneous diseases including psoriasis, lichen planus, viral warts, molluscum contagiosum, etc. In this case report, 3 patients with longstanding MF are presented, the 1st with the appearance of a circumscribed early-stage type MF lesion rapidly following a surgical excision of an infundibular cyst, the 2nd with the appearance of a unique unilateral palmar tumoral MF lesion at the pressure site of a crutch, and the 3rd presented localized MF early stage lesions at the friction site of a belt. This report suggests that some MF patients may experience Koebner phenomenon-induced MF lesions and that MF should be added to the long list of skin diseases potentially exhibiting the Koebner phenomenon. PMID:26557075

  9. A rare phenomenon: oculonasal synkinesis.

    PubMed

    Ciloglu, N Sinem; Duran, Alpay; Buyukdogan, Hasan

    2014-10-01

    Oculonasal synkinesis is the simultaneous contraction of the orbicularis oculi and the compressor narium minor muscles. The etiology of this phenomenon is still unclear; congenital and traumatic reasons are considered to be responsible. Here we report a case of oculonasal synkinesis. PMID:25015551

  10. Translation as a Psycholinguistic Phenomenon

    ERIC Educational Resources Information Center

    Zasyekin, Serhiy

    2010-01-01

    The article sketches the outlines of a theoretical framework for the analysis of translation of literary texts, viewed as psycho-semiotic phenomenon and based on evaluation of earlier attempts in this direction, and on the results of a psycholinguistic empirical study of translations. Central to this framework is the recent insight that the human…

  11. The 'whistler-nozzle' phenomenon

    NASA Technical Reports Server (NTRS)

    Hussain, A. K. M. F.; Hasan, M. A. Z.

    1983-01-01

    The whistler nozzle is a simple device which can induce jet self-excitations of controllable amplitudes and frequencies and appears highly promising for many applications involving turbulent transport, combustion and aerodynamic noise. The characteristics of this curious phenomenon are documented for different values of the controlling parameters and attempts to explain the phenomenon. It is shown that the whistler excitation results from the coupling of two independent resonance mechanisms: shear-layer tone resulting from the impingement of the pipe-exit shear layer on the collar lip, and organ-pipe resonance of the pipe-nozzle. The crucial role of the shear-layer tone in driving the organ-pipe resonance is proven by reproducing the event in pipe-ring and pipe-hole configurations in the absence of the collar. It is also shown that this phenomenon is the strongest when the self-excitation frequency matches the preferred mode of the jet. Previously announced in STAR as N83-20706

  12. Ridge effect and alignment phenomenon

    SciTech Connect

    Lokhtin, I. P. Managadze, A. K. Snigirev, A. M.

    2013-05-15

    It is assumed that the ridge effect observed by the CMS Collaboration in proton-proton collisions at the LHC and the phenomenon observed by the Pamir Collaboration in emulsion experiments with cosmic rays and characterized by the alignment of spots on a film is a manifestation of the same as-yet-unknown mechanism of the emergence of a coplanar structure of events. A large coplanar effect at the LHC in the region of forward rapidities is predicted on the basis of this hypothesis and an analysis of experimental data.

  13. Relaxation phenomenon in composite materials

    NASA Astrophysics Data System (ADS)

    Moznine, R. El.; Blanc, F.; Lieutier, M.; Lefort, A.

    1998-08-01

    Dielectric measurement characteristics such as the dissipation factor, relative permittivity and conductivity as a function of temperature and frequency have been achieved on composite materials based on different epoxy resins filled with alumina inclusions. The analysis of the results show the presence of porosity and inhomogeneity in these materials. The study of the dissipation factor, as a function of temperature at high frequencies, has shown an unexpected absorption phenomenon in materials designed to be utilized as electrical insulators. The identification of the entities responsible for this relaxation shows that the entities result from one of the components of the material. These results can also confirm the inhomogeneity of the materials.

  14. Religion as a Natural Phenomenon

    ScienceCinema

    Dennett, Daniel [Tufts University, Boston, Massachusetts, United States

    2009-09-01

    Religion is a costly human activity that has evolved over the millennia. Why does it exist and how does it foster such powerful allegiances? To undertake a serious scientific study of religious practices and attitudes we must set aside a traditional exemption from scrutiny which religions have enjoyed. Religious adherents may not welcome this attention, but we should press ahead with it, since if we don't come to understand religion as a natural phenomenon, our attempts to deal with the problems that loom in the twenty-first century will likely be counterproductive.

  15. Religion as a Natural Phenomenon

    SciTech Connect

    Dennett, Daniel

    2006-02-15

    Religion is a costly human activity that has evolved over the millennia. Why does it exist and how does it foster such powerful allegiances? To undertake a serious scientific study of religious practices and attitudes we must set aside a traditional exemption from scrutiny which religions have enjoyed. Religious adherents may not welcome this attention, but we should press ahead with it, since if we don't come to understand religion as a natural phenomenon, our attempts to deal with the problems that loom in the twenty-first century will likely be counterproductive.

  16. Raynaud Phenomenon (Beyond the Basics)

    MedlinePlus

    ... an important way to maintain a normal body temperature. Specialized skin blood vessels constrict or narrow in response to cold temperatures. This reaction, called “vasoconstriction,” decreases blood flow to ...

  17. Cell phenomenology: The first phenomenon.

    PubMed

    Pattee, H H

    2015-12-01

    As a broad academic discipline phenomenology may be summarized as the study from a first person point of view of what appears to subjective human conscious experience. As a historical philosophical movement phenomenology was often motivated by the belief that subjective human experience is the proper foundation of all philosophy. I explore phenomena from a broader evolutionary and physical point of view. I consider a phenomenon as the subjective consequence of a physical interaction with an individual organism. In physical terms, a phenomenon requires some form of detection or measurement. What is detected is determined by the organism, and is potentially functional for the organism as a self or subject. The concept of function has meaning only for living organisms. The classical human mind-body problem is an ill-defined complicated case of the more general epistemic subject-object problem, which at the origin of life I reduce to the primitive symbol-matter problem. I argue that the first memory-based self-replicating unit, like a cell, is the most primitive case of a necessary symbol-matter distinction. The first phenomena, which include all forms or sensing, detection, and measurement, require a subject-object distinction, called the epistemic cut. It is only because of such a subject-object distinction that populations of individual subjects can selectively adapt to their environment by heritable variations. This basic evolutionary process requires distinguishing the individual's subjective phenomena from the objective events of inexorable physical laws. PMID:26140998

  18. Water condensation: a multiscale phenomenon.

    PubMed

    Jensen, Kasper Risgaard; Fojan, Peter; Jensen, Rasmus Lund; Gurevich, Leonid

    2014-02-01

    The condensation of water is a phenomenon occurring in multiple situations in everyday life, e.g., when fog is formed or when dew forms on the grass or on windows. This means that this phenomenon plays an important role within the different fields of science including meteorology, building physics, and chemistry. In this review we address condensation models and simulations with the main focus on heterogeneous condensation of water. The condensation process is, at first, described from a thermodynamic viewpoint where the nucleation step is described by the classical nucleation theory. Further, we address the shortcomings of the thermodynamic theory in describing the nucleation and emphasize the importance of nanoscale effects. This leads to the description of condensation from a molecular viewpoint. Also presented is how the nucleation can be simulated by use of molecular models, and how the condensation process is simulated on the macroscale using computational fluid dynamics. Finally, examples of hybrid models combining molecular and macroscale models for the simulation of condensation on a surface are presented. PMID:24749461

  19. The phenomenon of microbial uncultivability.

    PubMed

    Epstein, S S

    2013-10-01

    Most of the microbial diversity on our planet cannot be cultivated, and remains inaccessible. To bring the missing species into culture, microbiologists have introduced over the past decade a number of innovations aiming to meet the demands of new microbes and better mimic their natural conditions. This resulted in a significant increase in microbial recovery yet the real reasons why so many microbes do not grow on artificial media remain largely unknown. The recently proposed scout model of microbial life cycle may provide a partial explanation for the phenomenon. It postulates that transition from dormancy to activity is a stochastic process originating in noise-driven bistability. The model helps explain several otherwise perplexing observations, and informs the future cultivation efforts. PMID:24011825

  20. The phenomenon of Soviet science.

    PubMed

    Kojevnikov, Alexei

    2008-01-01

    The grand "Soviet experiment" constituted an attempt to greatly accelerate and even shortcut the gradual course of historical development on the assumption of presumed knowledge of the general laws of history. This paper discusses the parts of that experiment that directly concerned scientific research and, in fact, anticipated or helped define important global changes in the functioning of science as a profession and an institution during the twentieth century. The phenomenon of Soviet, or socialist, science is analyzed here from the comparative international perspective, with attention to similarities and reciprocal influences, rather than to the contrasts and dichotomies that have traditionally interested cold war-type historiography. The problem is considered at several levels: philosophical (Soviet thought on the relationship between science and society and the social construction of scientific knowledge); institutional (the state recognition of research as a separate profession, the rise of big science and scientific research institutes); demographic (science becoming a mass profession, with ethnic and gender diversity among scientists); and political (Soviet-inspired influences on the practice of science in Europe and the United States through the social relations of science movement of the 1930s and the Sputnik shock of the 1950s). PMID:18831319

  1. Risk as a social phenomenon.

    PubMed

    Jamison, Wesley V

    2003-01-01

    What do nuclear power, smoking, and eating beef have in common? The answer is multifaceted. They all share aspects of mass production and consumption, and therefore consumer confidence comes into play in evaluating each of the products' merits. They all produce some level of anxiety--be it in response to adverse media coverage, or the successes of adversarial interest groups in publicizing those products' weaknesses--among consumers who wonder what if any level of the product should be consumed. Finally, nuclear power, smoking, and eating beef all share risk; that is, the perceived and real detriments of producing and consuming those products. Whether or not the associated risks--from increased cancer to increased heart disease--are real is beside the point. When talking about risk, scientific education must deal with the perception of risk as much as its reality. Risk is a socially defined phenomenon, and as such, the successful scientists/communicator must understand the social evaluations of it. While many scientists take a rational view of risk evaluation and consumers often make rational decisions about technological and scientific risk based upon the costs and benefits of that technology, this approach is problematic for three reasons. First, the nature of modern risks has changed in that risk is complex, incomprehensible and uncontrollable to the average person. Second, the rational approach assumes that all costs and benefits of a technology, both real and potential, both current and future, can be known and therefore rationally evaluated. This is not the case. Third, evidence from Europe indicates that trust in information sources about risk has fallen, and thus classic scientific education campaigns that rely upon increasing public knowledge and acceptance of technological and scientific risk are problematic. Because of these factors we argue that effective scientific response must begin to understand the social components of risk if campaigns to shape

  2. Collapse phenomenon during Chartis collateral ventilation assessment.

    PubMed

    Gesierich, Wolfgang; Samitas, Konstantinos; Reichenberger, Frank; Behr, Juergen

    2016-06-01

    Chartis is increasingly used for bronchoscopic assessment of collateral ventilation before endobronchial valve (EBV) treatment for severe emphysema. Its prognostic value is, however, limited by the airway collapse phenomenon. The frequency and clinical significance of the collapse phenomenon remain largely unknown.We performed a retrospective analysis of 92 patients undergoing Chartis evaluation under spontaneous breathing (n=55) or jet ventilation (n=37) from May 2010 to November 2013. Collateral ventilation status (positive/negative/collapse phenomenon/unclear) was reassessed and correlated with high-resolution computed tomography (HRCT) fissure analysis and clinical response.In the absence of the collapse phenomenon, the predictive value of Chartis measurements and HRCT fissural analysis was comparable. The collapse phenomenon was observed in 31.5% of all assessments, and was more frequent in lower lobes (44.9% versus 16.9% in upper lobes) and under jet ventilation (41.4% versus 22.1% under spontaneous breathing). 69.8% of lobes with the collapse phenomenon had complete fissures. Most patients with the collapse phenomenon in the target lobe and complete fissures treated with EBVs were responders (n=11/15). All valve-treated collapse phenomenon patients with fissure defects were nonresponders (n=3).In the absence of the collapse phenomenon Chartis measurement is reliable to predict response to valve treatment. In patients with the collapse phenomenon, treatment decisions should be based on HRCT detection of fissure integrity. Chartis assessment should be performed under spontaneous breathing. PMID:27076587

  3. Monostotic fibrous dysplasia with Raynaud's phenomenon

    PubMed Central

    Kumar, K. V. S. Hari; Aravinda, K.; Narayanan, K.

    2015-01-01

    Fibrous dysplasia (FD) is a benign bone disorder characterized by alteration in bone morphology. Monostotic FD is the commonest variant and affects the craniofacial bones. Raynaud's phenomenon is recurrent vasospasm of the fingers and toes due to cold exposure. The disease is usually idiopathic or secondary to connective tissue disorders. Raynaud's phenomenon is not described previously with FD. We recently encountered two interesting patients of craniofacial monostotic FD with Raynaud's phenomenon and report the same in this report. PMID:26283854

  4. Electron string phenomenon: physics and use

    NASA Astrophysics Data System (ADS)

    Donets, Evgeny D.

    2004-01-01

    Electron string phenomenon arises as a result of phase transition of a state of multiply reflected electron beam to this new discovered state of one component electron plasma and can be easily observed in the reflex mode of EBIS operation. The transition goes via a strong instability, which causes considerable electron energy spread, which in its turn suppresses the instability. Electron string state is a stationary state of hot pure electron plasma, which is heated by injected electron beam and cooled because of electron loses. Electron string is quiet in broad regions of experimental parameters, so that it is used for confinement and ionization of positive ions by electron impact to highly charge states similar to electron beams in EBIS. Application of electron strings instead of electron beams for ion production allows to save about 99% of electric power of electron beam and simultaneously to improve reliability of an ion source considerably. The JINR EBIS `Krion-2' in the string mode of operation is used for production of N7+, Ar16+ and Fe24+ ion beams and their acceleration to relativistic energies on the facility of the JINR super conducting one turn injection synchrotron `Nuklotron'. The tubular electron string possibly can exist and it is under study now theoretically and experiments are prepared now. Estimations show that a Tubular Electron String Ion Source (TESIS) could have up to three orders of magnitude higher ion output then a Linear one (LESIS). In frames of nuclear astrophysics electron strings can be used for research of fusion nuclear reactions at low energies in conditions when both beam and target nuclei do not carry orbital electrons. The project NARITA — Nuclear Astrophysics Researches in an Ion Trap Apparatus is proposed. Polarization effects also can be studied.

  5. Evaluating method for the double image phenomenon of LED lighting

    NASA Astrophysics Data System (ADS)

    Wu, Wen-Hong; Kuo, Chao-Hui; Hung, Min-Wei; Huang, Kuo-Cheng

    In recent years, the overriding advantages long life, high efficiency, small size and short reaction time have made LED become a viable alternative to conventional light sources. LED lighting sources are usually composed of several individual LED cells which must be mounted on a panel as a lighting module. Being composed of several individual LED cells, the LED sources will cause the double image phenomenon. The double image phenomenon is more obvious when the LED sources are more closer, such as LED table lamp, and limits the applications of LED sources. By using a proper secondary optical lens, the double image phenomenon can be reduced. In this research, an evaluating method based on image processing is developed for the double image phenomenon of a LED sources. By analyzing the gray-scale of the grabbed image which is obtained by putting a rob under a LED source, an index of double image can be established and be a criterion to judge different LED sources. Furthermore, a series of LED lighting simulations are shown in this paper and several type of secondary optical lens are compared and discussed in this paper as well.

  6. Visual light flash phenomenon. [Apollo 17 mission

    NASA Technical Reports Server (NTRS)

    Pinsky, L. S.; Osborne, W. Z.; Bailey, J. V.

    1973-01-01

    Light flash phenomenon observed by crewmen on Apollo 14, 15, 16, and 17 are analyzed. The passage of cosmic rays through the crewman's head and eyes was recorded by the Apollo light flash moving emulsion detector. Events of all the light flash observations are tabulated. It is suggested that the most probable explanation of the phenomenon is that it is caused by cosmic rays penetrating the eyes and retinas of the observers.

  7. Orgasm Induced Seizures: A Rare Phenomenon

    PubMed Central

    Chaukimath, SP; Patil, PS

    2015-01-01

    A variety of stimuli can cause reflex seizures, Some triggers include light, music and cognitive phenomenon. There are case reports however where the phenomenon of sexual activity has been a trigger for epileptic seizures. Most of these cases reported are in women so far, and were found to be localized to right cerebral hemisphere. We report a case of a 36-year-old male with orgasm-induced seizures, with other atypical features compared to majority of previous reports. PMID:27057393

  8. Orgasm Induced Seizures: A Rare Phenomenon.

    PubMed

    Chaukimath, S P; Patil, P S

    2015-01-01

    A variety of stimuli can cause reflex seizures, Some triggers include light, music and cognitive phenomenon. There are case reports however where the phenomenon of sexual activity has been a trigger for epileptic seizures. Most of these cases reported are in women so far, and were found to be localized to right cerebral hemisphere. We report a case of a 36-year-old male with orgasm-induced seizures, with other atypical features compared to majority of previous reports. PMID:27057393

  9. Validation of the Impostor Phenomenon among Managers.

    PubMed

    Rohrmann, Sonja; Bechtoldt, Myriam N; Leonhardt, Mona

    2016-01-01

    Following up on earlier investigations, the present research aims at validating the construct impostor phenomenon by taking other personality correlates into account and to examine whether the impostor phenomenon is a construct in its own right. In addition, gender effects as well as associations with dispositional working styles and strain are examined. In an online study we surveyed a sample of N = 242 individuals occupying leadership positions in different sectors. Confirmatory factor analyses provide empirical evidence for the discriminant validity of the impostor phenomenon. In accord with earlier studies we show that the impostor phenomenon is accompanied by higher levels of anxiety, dysphoric moods, emotional instability, a generally negative self-evaluation, and perfectionism. The study does not reveal any gender differences concerning the impostor phenomenon. With respect to working styles, persons with an impostor self-concept tend to show perfectionist as well as procrastinating behaviors. Moreover, they report being more stressed and strained by their work. In sum, the findings show that the impostor phenomenon constitutes a dysfunctional personality style. Practical implications are discussed. PMID:27313554

  10. PP composites with Hybrid Nanofillers: NTC phenomenon

    SciTech Connect

    Sarlin, Juha; Immonen, Kirsi

    2010-06-02

    Electric conductive plastic composites have a wide potential for commercial applications, some examples are EMI shielding housings and components in automotive industry and in consumer electronics, equipments in health care sector and fuel cell components. A phenomenon in conductive composites, especially in composites with carbon based fillers, is change of thermal induced change in conductivity as a result of morphological transitions. Usually the observed changes are practically irreversible. The phenomenon may cause increasing resistivity, usually called as 'positive temperature coefficient' (PTC) or decreasing resistivity, called 'negative temperature coefficient' (NTC), where the new morphology created by heat treatment is more favorable for electric conductivity compared to the original state. The existence of NTC is a sing of the lost potential in material design and processing. Therefore detailed information about the phenomenon gives us tools to develop high performance conductive materials. It this paper we discuss about NTC phenomenon observed in PP composites with CNT or in-situ synthesized CNT-PANi hybrid nanofiller with an amphiphilic dispersing agent. The goal of the paper is not to present a comprehensive model of this phenomenon; we present some experimental results which may be related to polymer-filler interactions. These details are a part of this complicated phenomenon.

  11. Validation of the Impostor Phenomenon among Managers

    PubMed Central

    Rohrmann, Sonja; Bechtoldt, Myriam N.; Leonhardt, Mona

    2016-01-01

    Following up on earlier investigations, the present research aims at validating the construct impostor phenomenon by taking other personality correlates into account and to examine whether the impostor phenomenon is a construct in its own right. In addition, gender effects as well as associations with dispositional working styles and strain are examined. In an online study we surveyed a sample of N = 242 individuals occupying leadership positions in different sectors. Confirmatory factor analyses provide empirical evidence for the discriminant validity of the impostor phenomenon. In accord with earlier studies we show that the impostor phenomenon is accompanied by higher levels of anxiety, dysphoric moods, emotional instability, a generally negative self-evaluation, and perfectionism. The study does not reveal any gender differences concerning the impostor phenomenon. With respect to working styles, persons with an impostor self-concept tend to show perfectionist as well as procrastinating behaviors. Moreover, they report being more stressed and strained by their work. In sum, the findings show that the impostor phenomenon constitutes a dysfunctional personality style. Practical implications are discussed. PMID:27313554

  12. Floating phenomenon and mode of color appearance

    NASA Astrophysics Data System (ADS)

    Aoki, Hironobu; Shinoda, Hiroyuki; Ikeda, Mitsuo

    2002-06-01

    We found an interesting phenomenon concerning the motion perception and the mode of color appearance. We suppose you are holding a stiff sheet of picture and move it laterally to and fro in front of the eye. Though the picture and all items in it move physically altogether with your hand, your perception is not always so. But when the picture that is a figure appears light-source color mode and a background of object color, a figure appears to slip on a background. We call this a 'floating phenomenon.' We predicted the occurrence of floating phenomenon depends on whether the color is perceived to belong to an object or not. To examine the relation between the floating phenomenon and the mode of color appearance, we measured the luminance threshold of floating phenomenon and the transition luminance between two color modes by constant stimulus method to use a mondrian. Our results show the floating never occurred when the target appeared as object color mode. The floating phenomenon may be caused by the separation of the light-source color from an object or week-belonging.

  13. The 'sparing phenomenon' of purpuric rash over tattooed skin.

    PubMed

    Pinal-Fernandez, Iago; Solans-Laqué, Roser

    2014-01-01

    Cutaneous complications associated with decorative tattooing are well known. However, the inhibition of a purpuric reaction by a tattoo is a fact that, as far as the authors know, has not been described before, fitting the definition of a 'sparing phenomenon', the absence of manifesting a particular skin disease in an area previously affected by another condition. From the clinical observation of purpuric lesions apparently inhibited by a tattoo in a 26-year-old patient, we performed an exact binomial test on the observed and expected proportion of purpuric lesions inside (0%, 95% confidence interval, CI, 0-2.6%) and outside (100%, 95% CI 97.4-100%) the tattooed skin, demonstrating a nonrandom distribution respecting the tattooed area (p < 0.001) and identifying the composition of the ink used in the tattoo (color pigment, glycerine, Hamamelis virginiana extract, water and alcohol). Moreover, we reviewed the cases of sparing phenomenon described in the literature. In conclusion this is the first report of a sparing phenomenon of purpuric lesions over tattooed skin. PMID:24356492

  14. Stability of the discretization of the electron avalanche phenomenon

    SciTech Connect

    Villa, Andrea; Barbieri, Luca; Gondola, Marco; Leon-Garzon, Andres R.; Malgesini, Roberto

    2015-09-01

    The numerical simulation of the discharge inception is an active field of applied physics with many industrial applications. In this work we focus on the drift-reaction equation that describes the electron avalanche. This phenomenon is one of the basic building blocks of the streamer model. The main difficulty of the electron avalanche equation lies in the fact that the reaction term is positive when a high electric field is applied. It leads to exponentially growing solutions and this has a major impact on the behavior of numerical schemes. We analyze the stability of a reference finite volume scheme applied to this latter problem. The stability of the method may impose a strict mesh spacing, therefore a proper stabilized scheme, which is stable whatever spacing is used, has been developed. The convergence of the scheme is treated as well as some numerical experiments.

  15. First time description of dismantling phenomenon

    PubMed Central

    Barrer, Laurence; Gimenez, Guy

    2015-01-01

    Dismantling is a complex psychic phenomenon, which is not easy to define, and little interest has been shown in the subject. The authors of this paper want to demonstrate that dismantling is the main defense mechanism in autism, bringing about de-consensus of senses. The effects perceived in a child with autistic disorder are passivity and lack of thought. The authors’ purpose here is to define the dismantled state and reveal its underlying process. This paper will therefore describe for the first time in literature, the dismantling phenomenon and will submit a metapsychological approach of this defense mechanism. PMID:25999871

  16. Fujita phenomenon in inhomogeneous fast diffusion system

    NASA Astrophysics Data System (ADS)

    Yang, Jinge; Zheng, Sining; Qu, Chengyuan

    2013-04-01

    This paper deals with the Fujita phenomenon for the Cauchy problem of an inhomogeneous fast diffusion system. Both the critical exponent and the second exponent are obtained. We observe that the inhomogeneous terms in the system substantially contribute to the critical exponent, in that the blow-up exponent region is obviously enlarged, with keeping the second critical exponent unchanged for small inhomogeneous sources.

  17. Fear of Success as a Situational Phenomenon.

    ERIC Educational Resources Information Center

    Lentz, Maxine E.

    1982-01-01

    Female undergraduates performed tasks that examined the effect of particular situations on Fear of Success (FOS). No differences in FOS were found among three experimental groups, although performance behavior differed significantly. Results suggest the need for better measures of both the situationality of FOS and the phenomenon of FOS itself.…

  18. Facilitated Communication: The Clinical and Social Phenomenon.

    ERIC Educational Resources Information Center

    Shane, Howard C., Ed.

    This text explains the phenomenon of facilitated communication (FC) from an empirical, data-based, and/or clinical perspective. It is not a how-to-facilitate text, but one that explores the clinical and sociological reality of FC. A common theme running through each of the papers in the book is the question of FC's legitimacy. The papers reveal…

  19. Systemic lupus erythematosus and Raynaud's phenomenon*

    PubMed Central

    Heimovski, Flavia Emilie; Simioni, Juliana A.; Skare, Thelma Larocca

    2015-01-01

    BACKGROUND Patients with systemic lupus erythematosus seem to belong to different serological and clinical subgroups of the disease. Genetic background can cause the appearance of these subgroups. OBJECTIVE To determine whether Brazilian patients who have systemic lupus erythematosus and Raynaud's phenomenon differ from those who do not. METHODS Retrospective analysis of 373 medical records of systemic lupus erythematosus patients studied for demographic, clinical and serological data. A comparative analysis was performed of individuals with and without RP. RESULTS There was a positive association between Raynaud's phenomenon and age at diagnosis (p=0.02), presence of anti-Sm (p=0.01) antibodies and anti-RNP (p<0.0001). Furthermore, a negative association was found between Raynaud's phenomenon and hemolysis (p=0.01), serositis (p=0.01), glomerulonephritis (p=0.0004) and IgM aCL (p=0.004) antibodies. CONCLUSION Raynaud's phenomenon patients appear to belong to a systemic lupus erythematosus subset with a spectrum of clinical manifestations located in a more benign pole of the disease. PMID:26734864

  20. Return to the "Getting Better Phenomenon"

    ERIC Educational Resources Information Center

    Carley, Glenn

    2007-01-01

    A school social work intervention called the "Getting Better Phenomenon" is redesigned as a curriculum resource for eighth- and ninth-grade teachers. The activities in the curriculum represent a synergy of provincial learning expectations; academic assessment and evaluation structures; teacher-guided delivery of student-generated "course" content;…

  1. LED's and the "Fluttering Heart" Phenomenon.

    ERIC Educational Resources Information Center

    Jewett, John W., Jr.

    1993-01-01

    Describes the nineteenth-century parlor trick entitled the Fluttering Heart phenomenon which uses a red heart on a bright blue background. Discusses theories concerning the apparent fluttering. Suggests doing the trick with a red light-emitting diode in a darkened room. (MVL)

  2. Left renal vein compression syndrome ("nutcracker phenomenon").

    PubMed

    Stassen, C M; Weil, E H; Janevski, B K

    1989-06-01

    Four cases are presented with clinical diagnosis of scrotal varicocele on the left side, and one case with ureter varices and left-sided haematuria as a result of compression of the left renal vein between the aorta and superior mesenteric artery (SMA), also known as "nutcracker phenomenon". The clinical signs and the radiological diagnostic methods of the condition are discussed. PMID:2544950

  3. Adolescent Attributes Contributing to the Imposter Phenomenon

    ERIC Educational Resources Information Center

    Caselman, Tonia D.; Self, Patricia A.; Self, Angela L.

    2006-01-01

    Personality traits, self-perceptions, beliefs, and feelings that accompany the Imposter Phenomenon (IP) have been identified in adults but little research with adolescents has been reported. The present research describes data from a sample of 11th and 12th graders in order to examine predictors of IP among adolescents. The participants completed…

  4. Bullying: Description and Analysis of the Phenomenon

    ERIC Educational Resources Information Center

    Benitez, Juan Luis; Justicia, Fernando

    2006-01-01

    This article purports to present this Special Issue about Bullying and, at the same time, to introduce the phenomenon of bullying in order to facilitate readers an updated vision about the problem that will be worked from different perspectives by researchers from national and international scope. With this purpose, we present some controversial…

  5. SODIUM-WATER HEAT EXCHANGER

    DOEpatents

    Simmons, W.R.; Koch, L.J.

    1962-04-17

    A heat exchanger comprising a tank for hot liquid and a plurality of concentric, double tubes for cool liquid extending vertically through the tank is described. These tubes are bonded throughout most of their length but have an unbonded portion at both ends. The inner tubes extend between headers located above and below the tanmk and the outer tubes are welded into tube sheets forming the top and bottom of the tank at locations in the unbonded portions of the tubes. (AEC)

  6. Numerical study of flow turning phenomenon

    NASA Astrophysics Data System (ADS)

    Baum, J. D.; Levine, J. N.

    1986-01-01

    A research project is currently being conducted that is to provide an understanding of the physical mechanisms by which energy is exchanged between the mean and acoustic flowfields in resonant combustion chambers, giving particular attention to solid rocket motors. The present paper is concerned with progress which has been made toward the understanding of the 'flow turning' phenomenon. This term is used to describe the loss of acoustic energy by the acoustic field in the combustor resulting from the inflow of combustion products through the lateral boundary of a combustion chamber containing longitudinal acoustic waves. Attention is given to the modeling of flow turning, acoustic refraction, the numerical solution, numerical results, acoustic wave propagation with no mean flow, and a flow turning study. The discussed research verifies the existence of the flow turning loss phenomenon.

  7. Phase transition phenomenon: A compound measure analysis

    NASA Astrophysics Data System (ADS)

    Kang, Bo Soo; Park, Chanhi; Ryu, Doojin; Song, Wonho

    2015-06-01

    This study investigates the well-documented phenomenon of phase transition in financial markets using combined information from both return and volume changes within short time intervals. We suggest a new measure for the phase transition behaviour of markets, calculated as a return distribution conditional on local variance in volume imbalance, and show that this measure successfully captures phase transition behaviour under various conditions. We analyse the intraday trade and quote dataset from the KOSPI 200 index futures, which includes detailed information on the original order size and the type of each initiating investor. We find that among these two competing factors, the submitted order size yields more explanatory power on the phenomenon of market phase transition than the investor type.

  8. The cutoff phenomenon in finite Markov chains.

    PubMed Central

    Diaconis, P

    1996-01-01

    Natural mixing processes modeled by Markov chains often show a sharp cutoff in their convergence to long-time behavior. This paper presents problems where the cutoff can be proved (card shuffling, the Ehrenfests' urn). It shows that chains with polynomial growth (drunkard's walk) do not show cutoffs. The best general understanding of such cutoffs (high multiplicity of second eigenvalues due to symmetry) is explored. Examples are given where the symmetry is broken but the cutoff phenomenon persists. PMID:11607633

  9. The feedback phenomenon applied to underwater acoustics

    NASA Astrophysics Data System (ADS)

    Roux, Philippe; Jordan, Jason E.; Kuperman, W. A.

    2002-11-01

    People are familiar with the feedback phenomenon that results in the loud sound heard when a musician plays an electric instrument directly into a speaker. Feedback occurs when a source and a receiver are connected both acoustically through the propagation medium and electrically through an amplifier in such way that the received signal is simultaneously and continuously added to the emitted signal. A resonance is then obtained when the emitter and the receiver are in phase. The resonant frequency appears to be highly sensitive to fluctuations of the propagation medium. The feedback phenomenon has been experimentally demonstrated as a means to monitor the temperature fluctuation of a shallow water environment [''Acoustic monitoring of the sea medium variability: experimental testing of new methods,'' by A. V. Furduev, Acoust. Phys. 47, No. 3, 361-368 (2001)]. The goal of our work is to reproduce the feedback experiment using an alternative method that decomposes the feedback phenomenon into an iterative process. Successful reproduction of the feedback is accomplished using a step-by-step algorithm which details the evolution of the system from the initial signal to its steady-state form. These experimental and numerical results illustrate the potential of the feedback process for use in narrow-band acoustical tomography.

  10. A scaling phenomenon in the difference of Shannon information uncertainty of fragments in heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Wang; Song, Yi-Dan; Qiao, Chun-Yuan; Wang, Shan-Shan; Wei, Hui-Ling; Ma, Yu-Gang; Cao, Xi-Guang

    2016-08-01

    Shannon information-entropy uncertainty is used to analyze fragments in the measured 140A MeV {}{40,48}Ca + 9Be and {}{58,64}Ni + 9Be reactions. A scaling phenomenon is found in the information-uncertainty difference of fragments between the reactions. The scaling phenomenon is explained in the manner of canonical ensemble theory, and is reproduced in simulated reactions using the antisymmetric molecular dynamics (AMD) and AMD + GEMINI models. The probes based on information uncertainty, requiring no equilibrium state of reaction, can be used in the non-equilibrium system, and bridge the results of the static thermodynamics models and the evolving dynamical transport models.

  11. Phenomenon of onset in magnetoplasmadynamic thrusters

    SciTech Connect

    Subramaniam, V.V.

    1986-01-01

    The performance of magnetoplasmadynamic (MPD) thrusters has been severely limited by onset. This destructive onset phenomenon refers to the abrupt increase in voltage oscillations accompanied by severe electrode erosion which occurs at a critical value of the current for a given mass flow rate. This research is aimed at explaining and quantifying onset. The steady, one-dimensional, self-field flow in the MPD thruster is first analyzed for frozen flow, equilibrium flow, and nonequilibrium flow. This quasi one-dimensional theory explains the behavior of efficiency and predicts a new mechanisms for the onset phenomenon. This model predicts that smoothly accelerating supersonic flow can exist only below a critical current level because of increasing back-EMF. This limit is interpreted as onset and correlates with the experimentally observed J/sup 2//m onset parameter. In order to quantify electrode erosion rates, the electrode-adjacent boundary layer is analyzed using the results of the quasi one-dimensional theory. The free-stream boundary conditions for the steady boundary-layer flow analysis are obtained from the results of the quasi one-dimensional theory.

  12. The ring phenomenon of diluted blood droplets.

    PubMed

    Ramsthaler, Frank; Schlote, J; Wagner, C; Fiscina, J; Kettner, M

    2016-05-01

    Bloodstain pattern analysis is occasionally required in practical forensic casework. Misinterpretations may occur in cases in which diluted bloodstains are formed either within the course of the crime or during cleaning attempts after the original crime. The resulting pale or diluted aspect of the bloodstains may also be produced by passive serum separation. To differentiate between diluted and non-diluted stains and the artifacts of pure serum separation, dripping experiments were performed using droplets of multiple sizes and dilutions dripped onto common indoor and fabric surfaces. In addition, pools of blood of different volumes were applied to solid surfaces with different inclinations to determine the conditions and properties of serum separation. This study yielded morphological characteristics that enable differentiation between stains of diluted and non-diluted blood: a prominent ring phenomenon indicates dilution with water. To elucidate the underlying physical mechanism of particle distribution within a blood stain, photomicrographs were taken during the drying process. The so-called contact line pinning effect was identified as the formation mechanism of this ring phenomenon. Serum separation was highly dependent on the applied blood volume, the ambient temperature, the time elapsed since the initial deposition, and the degree of floor inclination. PMID:26718842

  13. The United States pork niche market phenomenon.

    PubMed

    Honeyman, M S; Pirog, R S; Huber, G H; Lammers, P J; Hermann, J R

    2006-08-01

    After the broad industrialization of the US pork industry, there has been a development of niche markets for export and domestic pork; that is, there is a pork niche market phenomenon. The US pork niche market phenomenon is characterized, and 2 of the major markets are explained in detail. With the Midwest's tradition of a diversified family-based agriculture and record low hog prices of the late 1990s, the conditions were conducive for this phenomenon to develop. Pork niche markets utilize various sales methods including Internet sales, local abattoir sales, direct marketing, farmer networks, and targeting to organized groups. In 2003, there were approximately 35 to 40 active pork niche marketing efforts in Iowa. The Berkshire breed is an example of a swine breed that has had a recent resurgence because of niche markets. Berkshire pork is known for tenderness and excellent quality. Berkshire registrations have increased 4-fold in the last 10 yr. One of the larger niche marketers of "natural pork" is Niman Ranch Pork, which has more than 400 farmer-producers and processes about 2,500 pigs weekly. Many US consumers of pork are interested in issues concerning the environment, food safety, pig welfare, and pig farm ownership and structure. These consumers may be willing to pay more for pork from farmers who are also concerned about these issues. Small- and medium-sized swine farmers are active in pork niche markets. Niche markets claim product differentiation by superior or unique product quality and social attributes. Quality attributes include certain swine breeds, and meat quality, freshness, taste or flavor, and tenderness. Social or credence attributes often are claimed and include freedom from antibiotics and growth promotants; local family farm production; natural, organic, outdoor, or bedded rearing; humane rearing; known origin; environmentally friendly production; and the absence of animal by-products in the feed. Niche pork markets and alternative swine

  14. [Electroencephalographic characteristics of the deja vu phenomenon].

    PubMed

    Vlasov, P N; Cherviakov, A V; Gnezdinsiĭ, V V

    2013-01-01

    Déjà vu (DV, from French "already seen") is an aberration of psychic activity associated with transitory erroneous perception of novel circumstances, objects, or people as already known. An aim of the study was to investigate EEG characteristics of DV in patients with epilepsy. We studied 166 people (63.2% women, mean age 25.17±9.19 years). The DV phenomenon was studied in patients (27 people) and in a control group (139 healthy people). Patients were interviewed for DV characteristics and underwent a long (12-16 h) ambulatory EEG-monitoring study. In EEG, DV episodes in patients began with polyspike activity in the right temporal lobe and, in some cases, ended with the slow-wave theta-delta activity in the right hemisphere. PMID:23739447

  15. The Hitselberger sign as a perception phenomenon.

    PubMed

    Benz, B; Baumgarten, D

    1987-01-01

    In the Hitselberger test the patient has to estimate the magnitude of the tactile part of a compound audio-tactile stimulus. From this point of view it is doubtful, that the sign is a simple peripheral phenomenon based on the impairment of the facial nerve by tumor pressure. To investigate the process of audiotactile perception we developed a device which delivers a calibrated compound audio-tactile stimulus. In the tested 70 patients with different sensorineural lesions there was no significant difference between the percentage values of positive Hitselberger signs in the various diagnostic groups. Evaluation of the different factors influencing the Hitselberger test results in a new concept of audiotactile perception. PMID:3604652

  16. [The Linburg-Comstock phenomenon: a review].

    PubMed

    Kirchberger, Michael C; Hahn, P; Unglaub, F; Leclère, F M; Spies, C K

    2015-02-01

    Simultaneous flexion of thumb and fingers is described as the Linburg-Comstock phenomenon. Congenital and acquired coupling of the flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) tendons is the reason for this clinical entity. Additionally, coupling of the FPL and the flexor digitorum superficialis II or III has been described. The coupling can be between the muscles, the tendon sheaths or the tendons themselves. Asymptomatic and symptomatic coupling should be differentiated. In general symptomatic congenital or acquired coupling demands surgical intervention. We report about a 35-year-old patient with a congenital asymptomatic coupling of FPL and FDP-II who suffered a distorsion of the thumb. Afterwards she complained of pain and strength loss. An accessory tendon of 3 mm in diameter and 3.5 cm length between FPL and FDP-II was identified during surgery. The patient recovered completely after resection of this coupling. PMID:25706178

  17. [Burnout: rising interest phenomenon in stressful workplace].

    PubMed

    Della Valle, E; De Pascale, G; Cuccaro, A; Di Mare, M; Padovano, L; Carbone, U; Farinaro, E

    2006-01-01

    Many stressful situations, particularly strong and long time lasting, can induce the burnout syndrome. The definition "burnout" refers to emotional and exhausting conditions related to working environment. Since 70'ties, many studies, have focused on this topic, have assessed that this condition is much more frequent in some particular professional categories: teachers, physicians, nurses, social workers, policemen, judges (the so-called helping professions). The main syndrome characteristics are: physical and emotional fatigue, depersonalization, frustration for unsuccessful professional realization and reduced personal accomplishment in competence and productivity with decreasing critical sense towards working field. The Maslach Burnout Inventory (MBI) has been the most popular instrument for measuring burnout in medical research. The coherence of many studies results on helping professions in different countries, leads to the conclusion that basically burnout is a psycho-social phenomenon of international relevance. These studies have also identified personal, relational and environmental risk factors susceptible to prevention. PMID:16649514

  18. Liver Regeneration Is an Angiogenesis- Associated Phenomenon

    PubMed Central

    Drixler, Tom A.; Vogten, Mathys J.; Ritchie, Ewan D.; van Vroonhoven, Theo J. M. V.; Gebbink, Martijn F. B. G.; Voest, Emile E.; Borel Rinkes, Inne H. M.

    2002-01-01

    Objective To investigate whether liver regeneration is an angiogenesis-associated phenomenon. Summary Background Data Angiogenesis is predominantly known for its pivotal role in tumor growth. However, angiogenesis could also play a role in physiologic processes involving tissue repair, such as liver regeneration. Methods Mice subjected to 70% partial hepatectomy were treated with human angiostatin (100 mg/kg body weight). Regeneration-induced hepatic angiogenesis was determined by assessing intrahepatic microvascular density using CD31 staining of frozen liver sections. Liver regeneration was evaluated by assessing wet liver weights and BrdU incorporation in DNA at regular intervals after partial hepatectomy. Possible direct effects of angiostatin on hepatocytes were studied by assessment of liver enzymes (ASAT, ALAT, bilirubin, lactate dehydrogenase), MTT assay (cytotoxicity), aminophenol production (metabolic function), and TUNEL (apoptosis). Results In a regenerating liver, microvascular density increased by 38%. Angiostatin significantly inhibited this response by 60%. In addition, angiostatin inhibited liver regeneration by 50.4% and 24.9% on postoperative days 7 and 14, respectively. In control mice liver weights regained normalcy in 8 days, whereas those in angiostatin-treated mice normalized after 21 days. In angiostatin-treated mice, the maximal BrdU incorporation was decreased and delayed. Direct adverse effects of angiostatin on cultured and in vivo hepatocytes were not observed. Angiostatin neither induced necrosis on hematoxylin and eosin staining nor affected serum levels of liver enzymes. Conclusions Liver regeneration is accompanied by intrahepatic angiogenesis. Antiangiogenic treatment using angiostatin inhibits both phenomena. The authors conclude that liver regeneration is, at least in part, an angiogenesis-dependent phenomenon. PMID:12454508

  19. Gemicitabine-induced radiation recall phenomenon in 2 distinctive sites on the same patient.

    PubMed

    Zhang, Lulu; Patel, Raina; Mehdi, Syed

    2014-05-01

    Radiation recall phenomenon is an acute inflammatory reaction that develops in previously irradiated areas after administration of inciting agents systemically. The most common agents are anticancer drugs. Gemcitabine, a fluorine-substituted deoxycytidine analog, is widely used as a chemotherapy medication. Its antitumor effect results from the blockade of DNA synthesis and DNA repair. It has been used in advanced pancreatic, non-small-cell lung, bladder, and ovarian cancers; soft-tissue sarcoma; and non-Hodgkin lymphoma. It has occasionally been reported to cause radiation recall phenomenon. The time between radiation and recall may range from weeks to almost a year. PMID:24971429

  20. ACIDIC DEPOSITION PHENOMENON AND ITS EFFECTS: CRITICAL ASSESSMENT DOCUMENT

    EPA Science Inventory

    The Acidic Deposition Phenomenon and Its Effects: Critical Assessment Document (CAD) is a summary, integration, and interpretation of the current scientific understanding of acidic deposition. It is firmly based upon The Acidic Deposition Phenomenon and Its Effects: Critical Asse...

  1. Priming Intelligent Behavior: An Elusive Phenomenon

    PubMed Central

    Shanks, David R.; Newell, Ben R.; Lee, Eun Hee; Balakrishnan, Divya; Ekelund, Lisa; Cenac, Zarus; Kavvadia, Fragkiski; Moore, Christopher

    2013-01-01

    Can behavior be unconsciously primed via the activation of attitudes, stereotypes, or other concepts? A number of studies have suggested that such priming effects can occur, and a prominent illustration is the claim that individuals' accuracy in answering general knowledge questions can be influenced by activating intelligence-related concepts such as professor or soccer hooligan. In 9 experiments with 475 participants we employed the procedures used in these studies, as well as a number of variants of those procedures, in an attempt to obtain this intelligence priming effect. None of the experiments obtained the effect, although financial incentives did boost performance. A Bayesian analysis reveals considerable evidential support for the null hypothesis. The results conform to the pattern typically obtained in word priming experiments in which priming is very narrow in its generalization and unconscious (subliminal) influences, if they occur at all, are extremely short-lived. We encourage others to explore the circumstances in which this phenomenon might be obtained. PMID:23637732

  2. Anesthesia cutoff phenomenon: Interfacial hydrogen bonding

    SciTech Connect

    Chiou, J.S.; Ma, S.M.; Kamaya, H.; Ueda, I. )

    1990-05-04

    Anesthesia cutoff refers to the phenomenon of loss of anesthetic potency in a homologous series of alkanes and their derivatives when their sizes become too large. In this study, hydrogen bonding of 1-alkanol series (ethanol to eicosanol) to dipalmitoyl-L-alpha-phosphatidylcholine (DPPC) was studied by Fourier transform infrared spectroscopy (FTIR) in DPPC-D2O-in-CCl4 reversed micelles. The alkanols formed hydrogen bonds with the phosphate moiety of DPPC and released the DPPC-bound deuterated water, evidenced by increases in the bound O-H stretching signal of the alkanol-DPPC complex and also in the free O-D stretching band of unbound D2O. These effects increased according to the elongation of the carbon chain of 1-alkanols from ethanol (C2) to 1-decanol (C10), but suddenly almost disappeared at 1-tetradecanol (C14). Anesthetic potencies of these alkanols, estimated by the activity of brine shrimps, were linearly related to hydrogen bond-breaking activities below C10 and agreed with the FTIR data in the cutoff at C10.

  3. The Huygens entrainment phenomenon and thermoacoustic engines

    PubMed

    Spoor; Swift

    2000-08-01

    The earliest known reference to the mode-locking, or entrainment, of two maintained oscillators is Christiaan Huygens' description of two pendulum clocks "falling into synchrony" when hung on the same wall. We describe an analogous phenomenon in acoustics-the mode-locking of two thermoacoustic engines which have their cases rigidly welded together, but which are otherwise uncoupled. This "mass-coupling" might compete with acoustic coupling when the latter is used to enforce antiphase mode-locking in such engines, for vibration cancellation. A simple theory relating the phase difference between the engines in the locked state to the corresponding ratio of their pressure amplitudes is in excellent agreement with theory and numerical simulations. The theory's prediction relating the phase difference to the engines' natural frequency difference is qualitatively confirmed by experiment, despite larger experimental uncertainties. The mass coupling is relatively weak compared to the aforementioned acoustic coupling, and in general occurs in antiphase, so we conclude that mass coupling will not interfere with vibration cancellation by acoustic coupling in most circumstances. PMID:10955624

  4. Interhemispheric sensorimotor integration; an upper limb phenomenon?

    PubMed

    Ruddy, Kathy L; Jaspers, Ellen; Keller, Martin; Wenderoth, Nicole

    2016-10-01

    Somatosensory information from the limbs reaches the contralateral Primary Sensory Cortex (S1) with a delay of 23ms for finger, and 40ms for leg (somatosensory N20/N40). Upon arrival of this input in the cortex, motor evoked potentials (MEPs) elicited by Transcranial Magnetic Stimulation (TMS) are momentarily inhibited. This phenomenon is called 'short latency afferent inhibition (SAI)' and can be used as a tool for investigating sensorimotor interactions in the brain. We used SAI to investigate the process of sensorimotor integration in the hemisphere ipsilateral to the stimulated limb. We hypothesized that ipsilateral SAI would occur with a delay following the onset of contralateral SAI, to allow for transcallosal conduction of the signal. We electrically stimulated the limb either contralateral or ipsilateral to the hemisphere receiving TMS, using a range of different interstimulus intervals (ISI). We tested the First Dorsal Interosseous (FDI) muscle in the hand, and Tibialis Anterior (TA) in the lower leg, in three separate experiments. Ipsilateral SAI was elicited in the upper limb (FDI) at all ISIs that were greater than N20+18ms (all p<.05) but never at any earlier timepoint. No ipsilateral SAI was detected in the lower limb (TA) at any of the tested ISIs. The delayed onset timing of ipsilateral SAI suggests that transcallosal communication mediates this inhibitory process for the upper limb. The complete absence of ipsilateral SAI in the lower limb warrants consideration of the potential limb-specific differences in demands for bilateral sensorimotor integration. PMID:27425210

  5. Radiation recall reaction causing cardiotoxicity.

    PubMed

    Masri, Sofia Carolina; Misselt, Andrew James; Dudek, Arkadiusz; Konety, Suma H

    2014-01-01

    Radiation recall phenomenon is a tissue reaction that develops within a previously irradiated area, precipitated by the subsequent administration of certain chemotherapeutic agents. It commonly affects the skin, but can also involve internal organs with functional consequences. To our best knowledge, this phenomenon has never been reported as a complication on the heart and should be consider as a potential cause of cardiotoxicity. PMID:24755097

  6. Binary 193nm photomasks aging phenomenon study

    NASA Astrophysics Data System (ADS)

    Dufaye, Félix; Sartelli, Luca; Pogliani, Carlo; Gough, Stuart; Sundermann, Frank; Miyashita, Hiroyuki; Hidenori, Yoshioka; Charras, Nathalie; Brochard, Christophe; Thivolle, Nicolas

    2011-05-01

    193nm binary photomasks are still used in the semiconductor industry for the lithography of some critical layers for the nodes 90nm and 65nm, with high volumes and over long period. These 193nm binary masks seem to be well-known but recent studies have shown surprising degrading effects, like Electric Field induced chromium Migration (EFM) [1] or chromium migration [2] [3] . Phase shift Masks (PSM) or Opaque MoSi On Glass (OMOG) might not be concerned by these effects [4] [6] under certain conditions. In this paper, we will focus our study on two layers gate and metal lines. We will detail the effects of mask aging, with SEM top view pictures revealing a degraded chromium edge profile and TEM chemical analyses demonstrating the growth of a chromium oxide on the sidewall. SEMCD measurements after volume production indicated a modified CD with respect to initial CD data after manufacture. A regression analysis of these CD measurements shows a radial effect, a die effect and an isolated-dense effect. Mask cleaning effectiveness has also been investigated, with sulphate or ozone cleans, to recover the mask quality in terms of CD. In complement, wafer intrafield CD measurements have been performed on the most sensitive structure to monitor the evolution of the aging effect on mask CD uniformity. Mask CD drift have been correlated with exposure dose drift and isolated-dense bias CD drift on wafers. In the end, we will try to propose a physical explanation of this aging phenomenon and a solution to prevent from it occurring.

  7. Animal Rights as a Mainstream Phenomenon

    PubMed Central

    Rollin, Bernard E.

    2011-01-01

    Simple Summary The twentieth century has witnessed a bewildering array of ethical revolutions, from civil rights to environmentalism to feminism. Often ignored is the rise of massive societal concern across the world regarding animal treatment. Regulation of animal research exists in virtually all western countries, and reform of “factory farming” is regnant in Europe and rapidly emerging in the United States. Opponents of concern for animals often dismiss the phenomenon as rooted in emotion and extremist lack of appreciation of how unrestricted animal use has improved human life. Such a view totally ignores the rational ethical basis for elevating legal protection for animals, as explained in this essay. Abstract Businesses and professions must stay in accord with social ethics, or risk losing their autonomy. A major social ethical issue that has emerged in the past four decades is the treatment of animals in various areas of human use. Society's moral concern has outgrown the traditional ethic of animal cruelty that began in biblical times and is encoded in the laws of all civilized societies. There are five major reasons for this new social concern, most importantly, the replacement of husbandry-based agriculture with industrial agriculture. This loss of husbandry to industry has threatened the traditional fair contract between humans and animals, and resulted in significant amounts of animal suffering arising on four different fronts. Because such suffering is not occasioned by cruelty, a new ethic for animals was required to express social concerns. Since ethics proceed from preexisting ethics rather than ex nihilo, society has looked to its ethic for humans, appropriately modified, to find moral categories applicable to animals. This concept of legally encoded rights for animals has emerged as a plausible vehicle for reform. PMID:26486217

  8. Lucio's Phenomenon: Report of Two Cases and Review of the Literature.

    PubMed

    Roverano, S; Paira, S; Somma, F

    2000-08-01

    Hansen's disease is a chronic granulomatous disease of infectious origin. It has a worldwide distribution and a variety of clinical manifestations often involving the skin, nasal mucosa, and peripheral nerves. Lepromatous leprosy characterizes the condition of a large group of patients with little or no resistence to the infection. Several forms of lepromatous leprosy are recognized, including macular, nodular, and diffuse. Lucio's phenomenon is a rare but distinctive skin eruption seen in patients with diffuse lepromatous leprosy. The diffuse lesions of Lucio's phenomenon have a predilection for the extremities, can include nodules, and heal with atrophic stellate scars; histologically, a necrotizing vasculitis accompanied by a nonspecific inflammatory reaction may be seen. We describe two patients with Lucio's phenomenon who presented with nontender, painless, skin lesions with nodules in part perceptible only by palpation. Both patients were treated with multidrug therapy, and immunosuppressive doses of steroids as the suggested optimal treatment for this reactional state. However, Lucio's phenomenon is frequently fatal as a result of bacterial infection or sepsis, and both patients reported here died. We call attention to this particular and unusual skin manifestation of lepromatous leprosy, which can mimic rheumatic disease and other causes of vasculitis. This is especially likely to be unrecognized in nonendemic countries but cases will occasionally be seen in this age of extensive international travel. PMID:19078473

  9. Time-Dependent Rate Phenomenon in Viruses

    PubMed Central

    Aiewsakun, Pakorn

    2016-01-01

    ABSTRACT Among the most fundamental questions in viral evolutionary biology are how fast viruses evolve and how evolutionary rates differ among viruses and fluctuate through time. Traditionally, viruses are loosely classed into two groups: slow-evolving DNA viruses and fast-evolving RNA viruses. As viral evolutionary rate estimates become more available, it appears that the rates are negatively correlated with the measurement timescales and that the boundary between the rates of DNA and RNA viruses might not be as clear as previously thought. In this study, we collected 396 viral evolutionary rate estimates across almost all viral genome types and replication strategies, and we examined their rate dynamics. We showed that the time-dependent rate phenomenon exists across multiple levels of viral taxonomy, from the Baltimore classification viral groups to genera. We also showed that, by taking the rate decay dynamics into account, a clear division between the rates of DNA and RNA viruses as well as reverse-transcribing viruses could be recovered. Surprisingly, despite large differences in their biology, our analyses suggested that the rate decay speed is independent of viral types and thus might be useful for better estimation of the evolutionary time scale of any virus. To illustrate this, we used our model to reestimate the evolutionary timescales of extant lentiviruses, which were previously suggested to be very young by standard phylogenetic analyses. Our analyses suggested that these viruses are millions of years old, in agreement with paleovirological evidence, and therefore, for the first time, reconciled molecular analyses of ancient and extant viruses. IMPORTANCE This work provides direct evidence that viral evolutionary rate estimates decay with their measurement timescales and that the rate decay speeds do not differ significantly among viruses despite the vast differences in their molecular features. After adjustment for the rate decay dynamics, the

  10. Powerful Radio Burst Indicates New Astronomical Phenomenon

    NASA Astrophysics Data System (ADS)

    2007-09-01

    Astronomers studying archival data from an Australian radio telescope have discovered a powerful, short-lived burst of radio waves that they say indicates an entirely new type of astronomical phenomenon. Region of Strong Radio Burst Visible-light (negative greyscale) and radio (contours) image of Small Magellanic Cloud and area where burst originated. CREDIT: Lorimer et al., NRAO/AUI/NSF Click on image for high-resolution file ( 114 KB) "This burst appears to have originated from the distant Universe and may have been produced by an exotic event such as the collision of two neutron stars or the death throes of an evaporating black hole," said Duncan Lorimer, Assistant Professor of Physics at West Virginia University (WVU) and the National Radio Astronomy Observatory (NRAO). The research team led by Lorimer consists of Matthew Bailes of Swinburne University in Australia, Maura McLaughlin of WVU and NRAO, David Narkevic of WVU, and Fronefield Crawford of Franklin and Marshall College in Lancaster, Pennsylvania. The astronomers announced their findings in the September 27 issue of the online journal Science Express. The startling discovery came as WVU undergraduate student David Narkevic re-analyzed data from observations of the Small Magellanic Cloud made by the 210-foot Parkes radio telescope in Australia. The data came from a survey of the Magellanic Clouds that included 480 hours of observations. "This survey had sought to discover new pulsars, and the data already had been searched for the type of pulsating signals they produce," Lorimer said. "We re-examined the data, looking for bursts that, unlike the usual ones from pulsars, are not periodic," he added. The survey had covered the Magellanic Clouds, a pair of small galaxies in orbit around our own Milky Way Galaxy. Some 200,000 light-years from Earth, the Magellanic Clouds are prominent features in the Southern sky. Ironically, the new discovery is not part of these galaxies, but rather is much more distant

  11. Powerful Radio Burst Indicates New Astronomical Phenomenon

    NASA Astrophysics Data System (ADS)

    2007-09-01

    Astronomers studying archival data from an Australian radio telescope have discovered a powerful, short-lived burst of radio waves that they say indicates an entirely new type of astronomical phenomenon. Region of Strong Radio Burst Visible-light (negative greyscale) and radio (contours) image of Small Magellanic Cloud and area where burst originated. CREDIT: Lorimer et al., NRAO/AUI/NSF Click on image for high-resolution file ( 114 KB) "This burst appears to have originated from the distant Universe and may have been produced by an exotic event such as the collision of two neutron stars or the death throes of an evaporating black hole," said Duncan Lorimer, Assistant Professor of Physics at West Virginia University (WVU) and the National Radio Astronomy Observatory (NRAO). The research team led by Lorimer consists of Matthew Bailes of Swinburne University in Australia, Maura McLaughlin of WVU and NRAO, David Narkevic of WVU, and Fronefield Crawford of Franklin and Marshall College in Lancaster, Pennsylvania. The astronomers announced their findings in the September 27 issue of the online journal Science Express. The startling discovery came as WVU undergraduate student David Narkevic re-analyzed data from observations of the Small Magellanic Cloud made by the 210-foot Parkes radio telescope in Australia. The data came from a survey of the Magellanic Clouds that included 480 hours of observations. "This survey had sought to discover new pulsars, and the data already had been searched for the type of pulsating signals they produce," Lorimer said. "We re-examined the data, looking for bursts that, unlike the usual ones from pulsars, are not periodic," he added. The survey had covered the Magellanic Clouds, a pair of small galaxies in orbit around our own Milky Way Galaxy. Some 200,000 light-years from Earth, the Magellanic Clouds are prominent features in the Southern sky. Ironically, the new discovery is not part of these galaxies, but rather is much more distant

  12. Autoresuscitation: A Case and Discussion of the Lazarus Phenomenon

    PubMed Central

    Hannig, Kjartan Eskjaer; Hauritz, Rasmus Wulff; Grove, Erik Lerkevang

    2015-01-01

    Lazarus phenomenon or autoresuscitation is a very rare condition defined as delayed unassisted return of spontaneous circulation after cessation of cardiopulmonary resuscitation. Based on a case with a 67-year-old male who came back to life after discontinuation of cardiopulmonary resuscitation, we discuss the background and possible countermeasures related to the Lazarus phenomenon. PMID:26167181

  13. Fluorescence: An Interdisciplinary Phenomenon for Different Education Levels

    ERIC Educational Resources Information Center

    García, J. A.; Moreno, J. M.; Perales, F. J.; Romero, J.; Sánchez, P.; Gómez-Robledo, L.

    2012-01-01

    This paper shows the scientific foundations of a natural phenomenon of undoubted interest and applicability in our day, fluorescence, and its possibilities for teaching at three educational levels: primary, secondary and university. It begins by describing the nature of the phenomenon and continues by explaining how we work with students of the…

  14. The Grey Nomad Phenomenon: Changing the Script of Aging

    ERIC Educational Resources Information Center

    Onyx, Jenny; Leonard, Rosemary

    2007-01-01

    This article explores a relatively new and little understood phenomenon, that of the Australian Grey Nomads. Every year increasing numbers of older Australians take to the road. This article explores the phenomenon both empirically and theoretically. A grounded approach is used by which the experience is explored from an ethnographic account…

  15. Laurent phenomenon algebras and the discrete BKP equation

    NASA Astrophysics Data System (ADS)

    Okubo, Naoto

    2016-09-01

    We construct the Laurent phenomenon algebras the cluster variables of which satisfy the discrete BKP equation, the discrete Sawada–Kotera equation and other difference equations obtained by its reduction. These Laurent phenomenon algebras are constructed from seeds with a generalization of mutation-period property. We show that a reduction of a seed corresponds to a reduction of a difference equation.

  16. Raynaud's phenomenon and positive antinuclear antibodies in a malignancy.

    PubMed Central

    Tolosa-Vilella, C; Ordi-Ros, J; Vilardell-Tarres, M; Selva-O'Callaghan, A; Jordana-Comajuncosa, R

    1990-01-01

    Both Raynaud's phenomenon and the presence of antinuclear antibodies are uncommon features of malignant disease and the association of both with a malignancy extremely rare. The case is reported of a 78 year old woman who presented with Raynaud's phenomenon and positive antinuclear antibodies related to adenocarcinoma of unknown primary site. PMID:2256742

  17. [Study on whorl swarming growth phenomenon of Proteus mirabilis].

    PubMed

    He, Xianyuan; Liao, Sixiang; Liu, Junkang; Li, Kun; Liu, Yanxia; Yu, Lurong

    2015-02-01

    The present paper is aimed to explore the origins of Proteus mirabilis (PM) whorl swarming growth phenomenon. The whorl swarming growth phenomenon of PM was observed by changed bacterial culture inoculation time, humidity, vaccination practices, cultured flat placement, magnetic field, pH and other factors. Bacterial ring spiral direction of rotation is counterclockwise and the volatile growth process of PM was whorl swarming growth phenomenon. Spiro fluctuation phenomenon was of high frequency in the sealing tanks by cultured anytime inoculation, wherever inoculation technique applied or not, the presence or absence of the magnetic field, and wherever the dish position was. The experimental results showed that the whorl swarming growth phenomenon of PM requires specific pH environment, in which the facts may be relative to its genetic characteristics and the Earths rotation. PMID:25997280

  18. Kinesia paradoxa: a challenging Parkinson's phenomenon for simulation.

    PubMed

    Banou, Eirini

    2015-01-01

    The present work aims to study extensively the literature on the phenomenon of "kinesia paradoxa" presented in Parkinson's disease patients, who generally cannot move but under certain circumstances exhibit a sudden, brief period of mobility (walking or even running). The objective of this study was to identify the mechanisms causing this phenomenon and relate them with respectively computational simulations aiming to draw attention to gaps and weaknesses and possible directions for future research. The study of this phenomenon with the use of modeling techniques may be a decisive factor for its interpretation. PMID:25416986

  19. Acrocyanosis from phenazopyridine-induced sulfhemoglobinemia mistaken for Raynaud phenomenon.

    PubMed

    Kermani, Tanaz A; Pislaru, Sorin V; Osborn, Thomas G

    2009-04-01

    Rheumatologists are often asked to evaluate patients with Raynaud phenomenon. Occasionally, an alternate explanation is revealed such as acrocyanosis. Methemoglobinemia and sulfhemoglobinemia are rare causes of cyanosis that can be medication-induced. Both are known complications of therapy with phenazopyridine. We report an unusual case of a 45-year-old woman in whom sulfhemoglobinemia from chronic therapy with phenazopyridine was misdiagnosed as due to Raynaud phenomenon and limited scleroderma. This case illustrates the importance of taking into account medication-related adverse events when evaluating patients with Raynaud-like phenomenon. PMID:19300288

  20. Rumpel-Leede phenomenon presenting as a hypertensive urgency.

    PubMed

    Varela, Daniel; Tran, Dat; Ngamdu, Kyari Sumayin; Trullender, Brett; Mukherjee, Debabrata; Abbas, Aamer

    2016-04-01

    Rumpel-Leede (R-L) phenomenon is the rare event in which the small dermal capillaries of an extremity rupture in response to application of a compressive device to that extremity, such as when inflating a cuff during noninvasive blood pressure monitoring or when applying a tourniquet to draw blood. This capillary rupture results in formation of a petechial rash distal to the compressive device. R-L phenomenon is believed to occur most often in patients with underlying vascular disease, such as diabetes mellitus or thrombocytopenia. R-L phenomenon is most often benign, though it may rarely be associated with pain and discomfort. There is no treatment for this condition apart from treatment of the underlying vascular disease or thrombocytopenia. We report a 57-year-old woman who presented with hypertensive urgency and experienced R-L phenomenon during blood pressure cuff inflation. PMID:27034570

  1. Spontaneous Involution of Congenital Melanocytic Nevus With Halo Phenomenon

    PubMed Central

    Lee, Noo Ri; Chung, Hee-Chul; Hong, Hannah; Lee, Jin Wook

    2015-01-01

    Abstract: Congenital melanocytic nevus (CMN) is a neural crest-derived hamartoma, which appear at or soon after birth. CMN has a dynamic course and may show variable changes over time, including spontaneous involution. Spontaneous involution of CMN is a rare phenomenon and is often reported in association with halo phenomenon or vitiligo. The mechanism of halo phenomenon is yet to be investigated but is suggested to be a destruction of melanocytes by immune responses of cytotoxic T cells or IgM autoantibodies. Here, the authors report an interesting case of spontaneously regressed medium-sized CMN with halo phenomenon and without vitiligo, which provides evidence that cytotoxic T cells account for the halo formation and pigmentary regression of CMN. PMID:26588343

  2. Rumpel-Leede phenomenon presenting as a hypertensive urgency

    PubMed Central

    Tran, Dat; Ngamdu, Kyari Sumayin; Trullender, Brett; Mukherjee, Debabrata; Abbas, Aamer

    2016-01-01

    Rumpel-Leede (R-L) phenomenon is the rare event in which the small dermal capillaries of an extremity rupture in response to application of a compressive device to that extremity, such as when inflating a cuff during noninvasive blood pressure monitoring or when applying a tourniquet to draw blood. This capillary rupture results in formation of a petechial rash distal to the compressive device. R-L phenomenon is believed to occur most often in patients with underlying vascular disease, such as diabetes mellitus or thrombocytopenia. R-L phenomenon is most often benign, though it may rarely be associated with pain and discomfort. There is no treatment for this condition apart from treatment of the underlying vascular disease or thrombocytopenia. We report a 57-year-old woman who presented with hypertensive urgency and experienced R-L phenomenon during blood pressure cuff inflation. PMID:27034570

  3. Glow phenomenon surrounding the vertical stabilizer and OMS pods

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This 35mm frame, photographed as the Space Shuttle Columbia was orbiting Earth during a 'night' pass, documents the glow phenomenon surrounding the vertical stabilizer and the Orbital Maneuvering System (OMS) pods of the spacecraft.

  4. Coronary Slow Flow Phenomenon Clinical Findings and Predictors

    PubMed Central

    Sanati, Hamidreza; Kiani, Reza; Shakerian, Farshad; Firouzi, Ata; Zahedmehr, Ali; Peighambari, Mohammadmehdi; Shokrian, Leila; Ashrafi, Peiman

    2016-01-01

    Background: In some patients with chest pain, selective coronary angiography reveals slow contrast agent passage through the epicardial coronary arteries in the absence of stenosis. This phenomenon has been designated the slow coronary flow (SCF) phenomenon. Objectives: In this study, we aimed to describe the demographic and clinical findings and presence of common atherosclerosis risk factors in patients with the SCF phenomenon. Patients and Methods: Between October 2014 and March 2015, demographic data, clinical histories, atherosclerosis risk factors, and laboratory and angiographic findings were recorded for all consecutive patients scheduled for coronary angiography and diagnosed with the SCF phenomenon, as well as a control group (patients with normal epicardial coronary arteries; NECA). SCF was diagnosed based on the thrombolysis in myocardial infarction frame count (TFC). A TFC > 27 indicated a diagnosis of SCF phenomenon. Results: Among the 3600 patients scheduled for selective coronary angiography, 75 (2%) met the SCF criteria. SCF and NECA patients did not exhibit statistically significant differences in traditional risk factors except for hypertension, which was more prevalent in SCF than NECA patients (52% versus 31%, P = 0.008). A multivariable analysis indicated a low body mass index, presence of hypertension, low high-density lipoprotein cholesterol (HDL-c) level, and high hemoglobin level as independent predictors of the SCF phenomenon; of these, hypertension was the strongest predictor (odds ratio = 6.3, 95% confidence interval: 2.2 - 17.9, P = 0.001). Conclusions: The SCF phenomenon is relatively frequent, particularly among patients with acute coronary syndrome who are scheduled for coronary angiography. Hypertension, a low HDL-c level, and high hemoglobin level can be considered independent predictors of this phenomenon. PMID:26889458

  5. Experimental results on the enhanced backscatter phenomenon and its dynamics

    NASA Astrophysics Data System (ADS)

    Wu, Chensheng; Nelson, William; Ko, Jonathan; Davis, Christopher C.

    2014-10-01

    Enhanced backscatter effects have long been predicted theoretically and experimentally demonstrated. The reciprocity of a turbulent channel generates a group of paired rays with identical trajectory and phase information that leads to a region in phase space with double intensity and scintillation index. Though simulation work based on phase screen models has demonstrated the existence of the phenomenon, few experimental results have been published describing its characteristics, and possible applications of the enhanced backscatter phenomenon are still unclear. With the development of commercially available high powered lasers and advanced cameras with high frame rates, we have successfully captured the enhanced backscatter effects from different reflection surfaces. In addition to static observations, we have also tilted and pre-distorted the transmitted beam at various frequencies to track the dynamic properties of the enhanced backscatter phenomenon to verify its possible application in guidance and beam and image correction through atmospheric turbulence. In this paper, experimental results will be described, and discussions on the principle and applications of the phenomenon will be included. Enhanced backscatter effects are best observed in certain levels of turbulence (Cn 2≍10-13 m-2/3), and show significant potential for providing self-guidance in beam correction that doesn't introduce additional costs (unlike providing a beacon laser). Possible applications of this phenomenon include tracking fast moving object with lasers, long distance (>1km) alignment, and focusing a high-power corrected laser beam over long distances.

  6. The Science of Low Energy Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Storms, Edmund

    2007-03-01

    The large literature describing the anomalous behavior attributed to cold fusion or low energy nuclear reactions has been critically described in a recently published book. Over 950 publications are evaluated allowing the phenomenon to be understood. A new class of nuclear reactions has been discovered that are able to generate practical energy without significant radiation or radioactivity. Edmund K Storms, The Science of Low Energy Nuclear Reactions, in press (2006). Also see: http://www.lenr-canr.org/StudentsGuide.htm .

  7. High prevalence of isolated sleep paralysis: kanashibari phenomenon in Japan.

    PubMed

    Fukuda, K; Miyasita, A; Inugami, M; Ishihara, K

    1987-06-01

    In Japan, a set of experiences called kanashibari is considered identical with isolated sleep paralysis. We investigated this phenomenon by means of a questionnaire administered to 635 college students (390 men and 245 women). Of all subjects, about 40% had experienced at least one episode of kanashibari [subjects of K(+)]. Therefore, isolated sleep paralysis is apparently a more common phenomenon than is usually appreciated. About half of the subjects of K(+) reported that they had been under "physical or psychological stress" or in a "disturbed sleep and wakefulness cycle" immediately before the episode. Many subjects of K(+) experienced the first episode in adolescence. In the distribution of age of first attack, the peak occurred at an earlier age in women subjects than in men subjects. These findings suggest that two factors influence the occurrence of the phenomenon. One is exogenous physical or psychological load and the other is endogenous biological development. PMID:3629091

  8. The role of ocean phenomenon in music compositions

    NASA Astrophysics Data System (ADS)

    Liu, Chi-Min

    2016-04-01

    This is a preliminarily interdisciplinary study for exploring the elements of ocean phenomenon appearing in some compositions of classical music. The so-called ocean phenomenon contain wave conditions, climate change, coastal landform, and other natural events around or over the sea. In some music compositions, it is apparent that natural phenomenon over the sea influence the composers' moods and the music pieces they composed. In this poster, some music compositions in the 19th and the early 20th centuries will be introduced to demonstrate the relation between ocean and music works. These works include Meeresstille by Schubert, Étude Op.25 No.12 by Chopin, Fingal's Cave Overture by Mendelssohn, Der Fliegende Holländer by Wagner and La Mer by Debussy. In addition, present idea may give a novel way for music teachers to elucidate the knowledge of ocean science in classes.

  9. Statistical Agent Based Modelization of the Phenomenon of Drug Abuse

    NASA Astrophysics Data System (ADS)

    di Clemente, Riccardo; Pietronero, Luciano

    2012-07-01

    We introduce a statistical agent based model to describe the phenomenon of drug abuse and its dynamical evolution at the individual and global level. The agents are heterogeneous with respect to their intrinsic inclination to drugs, to their budget attitude and social environment. The various levels of drug use were inspired by the professional description of the phenomenon and this permits a direct comparison with all available data. We show that certain elements have a great importance to start the use of drugs, for example the rare events in the personal experiences which permit to overcame the barrier of drug use occasionally. The analysis of how the system reacts to perturbations is very important to understand its key elements and it provides strategies for effective policy making. The present model represents the first step of a realistic description of this phenomenon and can be easily generalized in various directions.

  10. Tears of wine: new insights on an old phenomenon

    NASA Astrophysics Data System (ADS)

    Venerus, David C.; Nieto Simavilla, David

    2015-11-01

    Anyone who has enjoyed a glass of wine has undoubtedly noticed the regular pattern of liquid beads that fall along the inside of the glass, or ‘tears of wine.’ The phenomenon is the result of a flow against gravity along the liquid film on the glass, which is induced by an interfacial tension gradient. It is generally accepted that the interfacial tension gradient is due to a composition gradient resulting from the evaporation of ethanol. We re-examine the tears of wine phenomenon and investigate the importance of thermal effects, which previously have been ignored. Using a novel experiment and simple model we find that evaporative cooling contributes significantly to the flow responsible for wine tears, and that this phenomenon occurs primarily because of the thermodynamic behavior of ethanol-water mixtures. Also, the regular pattern of tear formation is identified as a well-known hydrodynamic instability.

  11. Ringing phenomenon based whispering-gallery-mode sensing

    PubMed Central

    Ye, Ming-Yong; Shen, Mei-Xia; Lin, Xiu-Min

    2016-01-01

    Highly sensitive sensing is one of the most important applications of whispering-gallery-mode (WGM) microresonators, which is usually accomplished through a tunable continuous-wave laser sweeping over a whispering-gallery mode with the help of a fiber taper in a relative slow speed. It is known that if a tunable continuous-wave laser sweeps over a high quality whispering-gallery mode in a fast speed, a ringing phenomenon will be observed. The ringing phenomenon in WGM microresonators is mainly used to measure the Q factors and mode-coupling strengths. Here we experimentally demonstrate that the WGM sensing can be achieved based on the ringing phenomenon. This kind of sensing is accomplished in a much shorter time and is immune to the noise caused by the laser wavelength drift. PMID:26796871

  12. Self-Propelled Hovercraft Based on Cold Leidenfrost Phenomenon.

    PubMed

    Shi, Meng; Ji, Xing; Feng, Shangsheng; Yang, Qingzhen; Lu, Tian Jian; Xu, Feng

    2016-01-01

    The Leidenfrost phenomenon of liquid droplets levitating and dancing when placed upon a hot plate due to propulsion of evaporative vapor has been extended to many self-propelled circumstances. However, such self-propelled Leidenfrost devices commonly need a high temperature for evaporation and a structured solid substrate for directional movements. Here we observed a "cold Leidenfrost phenomenon" when placing a dry ice device on the surface of room temperature water, based on which we developed a controllable self-propelled dry ice hovercraft. Due to the sublimated vapor, the hovercraft could float on water and move in a programmable manner through designed structures. As demonstrations, we showed that the hovercraft could be used as a cargo ship or a petroleum contamination collector without consuming external power. This phenomenon enables a novel way to utilize programmable self-propelled devices on top of room temperature water, holding great potential for applications in energy, chemical engineering and biology. PMID:27338595

  13. Tears of wine: new insights on an old phenomenon.

    PubMed

    Venerus, David C; Nieto Simavilla, David

    2015-01-01

    Anyone who has enjoyed a glass of wine has undoubtedly noticed the regular pattern of liquid beads that fall along the inside of the glass, or 'tears of wine.' The phenomenon is the result of a flow against gravity along the liquid film on the glass, which is induced by an interfacial tension gradient. It is generally accepted that the interfacial tension gradient is due to a composition gradient resulting from the evaporation of ethanol. We re-examine the tears of wine phenomenon and investigate the importance of thermal effects, which previously have been ignored. Using a novel experiment and simple model we find that evaporative cooling contributes significantly to the flow responsible for wine tears, and that this phenomenon occurs primarily because of the thermodynamic behavior of ethanol-water mixtures. Also, the regular pattern of tear formation is identified as a well-known hydrodynamic instability. PMID:26548566

  14. Tears of wine: new insights on an old phenomenon

    PubMed Central

    Venerus, David C.; Nieto Simavilla, David

    2015-01-01

    Anyone who has enjoyed a glass of wine has undoubtedly noticed the regular pattern of liquid beads that fall along the inside of the glass, or ‘tears of wine.’ The phenomenon is the result of a flow against gravity along the liquid film on the glass, which is induced by an interfacial tension gradient. It is generally accepted that the interfacial tension gradient is due to a composition gradient resulting from the evaporation of ethanol. We re-examine the tears of wine phenomenon and investigate the importance of thermal effects, which previously have been ignored. Using a novel experiment and simple model we find that evaporative cooling contributes significantly to the flow responsible for wine tears, and that this phenomenon occurs primarily because of the thermodynamic behavior of ethanol-water mixtures. Also, the regular pattern of tear formation is identified as a well-known hydrodynamic instability. PMID:26548566

  15. An Isoratio Method and an Isoratio Scaling Phenomenon in Heavy-Ion Collisions

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Wang; Qiao, Chun-Yuan

    2016-07-01

    An isoratio method is proposed to study the chemical potential of neutrons (protons) from the yield ratio of isotopes (isotones) differing in neutron-excess (I = N ‑ Z). The measured fragments in the 140 A MeV 40,48Ca and 58,64Ni + 9Be reactions, as well as those in the simulated 58,64Ni + 9Be reactions by using the antisymmetric molecular dynamics (AMD) model plus the secondary decay model gemini, have been adopted to perform the isoratio analysis. The results of the isoratio method verify that they are similar to that of the well known isoscaling method. The isoratio scaling phenomenon suggested by the isoratio method has also been found in the measured data and the fragments simulated by the AMD + gemini models. Supported by the Program for Science and Technology Innovation Talents in Universities of Henan Province under Grant No. 13HASTIT046

  16. Large-scale sodium-basalt concrete reaction test LSC-1

    SciTech Connect

    McCormick, M.W.; Muhlestein, L.D.; Colburn, R.P.; Winkel, B.V.

    1981-06-01

    The energy and hydrogen released from sodium-concrete reactions must be considered the analysis of beyond-design basis accidents for breeder reactors. Consequently, a large-scale sodium-basalt concrete reaction test was completed in the Large Sodium Fire Facility (LSFF) at the Hanford Engineering Development Laboratory (HEDL). 454 kg of sodium at 593{sup 0}C was spilled onto 0.84 m{sup 2} of basalt concrete 0.61 m deep containing two layers of reinforcing steel bar. From the data obtained, it was possible to complete a mass and energy balance for this test. The hydrogen generation and generation rate as functions of time for the duration of the test were determined. The major contribution to the chemical energy was energy associated with the formation of hydrogen (sodium-water reactions).

  17. What types of investors generate the two-phase phenomenon?

    NASA Astrophysics Data System (ADS)

    Ryu, Doojin

    2013-12-01

    We examine the two-phase phenomenon described by Plerou, Gopikrishnan, and Stanley (2003) [1] in the KOSPI 200 options market, one of the most liquid options markets in the world. By analysing a unique intraday dataset that contains information about investor type for each trade and quote, we find that the two-phase phenomenon is generated primarily by domestic individual investors, who are generally considered to be uninformed and noisy traders. In contrast, our empirical results indicate that trades by foreign institutions, who are generally considered informed and sophisticated investors, do not exhibit two-phase behaviour.

  18. [Disorders in sodium-water balance].

    PubMed

    Petitclerc, Thierry

    2013-02-01

    Water balance control is aimed at normalizing cellular hydration, and sodium balance control at normalizing extracellular volume. Water balance control is based on the regulation of body fluid tonicity, while the control of sodium balance is based on the regulation of effective arterial volume. Disorders of water balance act on cellular hydration: primary disorders induce a proportional change in tonicity; secondary disorders are induced by a change in tonicity or effective arterial volume. Disorders of sodium balance act on extracellular volume: primary disorders of sodium balance induce a change in effective arterial volume; secondary disorders are induced by a change in effective arterial volume. Physical examination of the patient allows assessing the extracellular volume and the severity of the sodium balance disorder. Natremia - that generally reflects tonicity - allows to assess cellular hydration and to determine the type of water balance disorder. In the case of natremia disturbance, the assessment of both the tonicity and the extracellular volume allows the determination of the type of water and/or sodium balance disorder that is necessary for prescribing the adequate therapy. PMID:23177272

  19. Succession Planning and the Imposter Phenomenon in Higher Education

    ERIC Educational Resources Information Center

    Parkman, Anna; Beard, Roxanne

    2008-01-01

    This article illustrates the impact of the imposter phenomenon on succession planning in higher education, describes imposter behavior in detail and offers a number of strategies to address these behaviors. The authors examine how to reduce the likelihood that an imposter is placed into the succession pipeline and how to reduce imposter behaviors…

  20. A Modular Approach for Teaching Partial Discharge Phenomenon through Experiment

    ERIC Educational Resources Information Center

    Chatterjee, B.; Dey, D.; Chakravorti, S.

    2011-01-01

    Partial discharge (PD) monitoring is an effective predictive maintenance tool for electrical power equipment. As a result, an understanding of the theory related to PD and the associated measurement techniques is now necessary knowledge for power engineers in their professional life. This paper presents a modular course on PD phenomenon in which…

  1. Peak Shift Phenomenon: A Teaching Activity for Basic Learning Theory

    ERIC Educational Resources Information Center

    Keith, Kenneth D.

    2002-01-01

    Stimulus discrimination is a standard subject in undergraduate courses presenting basic principles of learning, and a particularly interesting aspect of discrimination is the peak shift phenomenon. Peak shift occurs in generalization tests following intradimensional discrimination training as a displacement of peak responding away from the S+ (a…

  2. Kasabach-Merritt phenomenon and prenatal counseling: a case series.

    PubMed

    Beissel, Anne; Riou, Stéphanie; Fischer Fumeaux, Céline Julie; Cassart, Marie; Blanc, Sébastien; Claris, Olivier; Guibaud, Laurent

    2016-07-01

    Kasabach-Merritt phenomenon can be encountered in the perinatal period. No consensus exists regarding prenatal management. We report one prenatal case leading to therapeutic abortion and one neonatal case, successfully treated by a multimodal therapy. Prenatal counseling should include the possibility of neonatal multimodal treatment that can lead to favorable outcomes. PMID:27386131

  3. A Study of the Impostor Phenomenon among Male Nurse Educators

    ERIC Educational Resources Information Center

    Pierce, Stephanie S.

    2011-01-01

    The Clance Impostor Phenomenon Scale and the Rosenberg Self-Esteem Scale continue to be used to measure impostor characteristics and levels of self-esteem in aggregate populations in corporate and academic environments. Previous studies have focused on females or female dominate populations. A correlational study of nursing educators that are male…

  4. The Gibbs Phenomenon for Series of Orthogonal Polynomials

    ERIC Educational Resources Information Center

    Fay, T. H.; Kloppers, P. Hendrik

    2006-01-01

    This note considers the four classes of orthogonal polynomials--Chebyshev, Hermite, Laguerre, Legendre--and investigates the Gibbs phenomenon at a jump discontinuity for the corresponding orthogonal polynomial series expansions. The perhaps unexpected thing is that the Gibbs constant that arises for each class of polynomials appears to be the same…

  5. Meteor phenomenon erroneous related in mass-media

    NASA Astrophysics Data System (ADS)

    Grigore, V.; Ogescu, D. M.

    2005-02-01

    In this article are shortly presented some aspects of erroneous narration of some astronomical events, especially those related to meteors, which have appeared in the Romanian press and publications during the last few years. We have identified those errors and we suggest some simple measures that can be taken in the near future, in order to counteract this phenomenon.

  6. The Success-Breeds-Success Phenomenon and Bibliometric Processes.

    ERIC Educational Resources Information Center

    Tague, Jean

    1981-01-01

    Describes success-breeds-success phenomenon by single and multiple-urn models, and shows that these models lead to a negative binomial distribution for the total number of successes and to a Zipf-Mandelbrot law for the number of sources contributing a specified number of successes. Ten references are cited. (FM)

  7. The Gopniks as a Phenomenon in the Youth Community

    ERIC Educational Resources Information Center

    Gavriliuk, V. V.

    2011-01-01

    The socialization mechanisms of young people in Russia are greatly affected by the prevalence of youth subcultures, both socially positive ones and marginal subcultures that include antisocial ones. In this paper, the author focuses on a phenomenon in the youth community that is quite prevalent in the provinces of Russia, the "gopniki" [street…

  8. Exploring Fourier Series and Gibbs Phenomenon Using Mathematica

    ERIC Educational Resources Information Center

    Ghosh, Jonaki B.

    2011-01-01

    This article describes a laboratory module on Fourier series and Gibbs phenomenon which was undertaken by 32 Year 12 students. It shows how the use of CAS played the role of an "amplifier" by making higher level mathematical concepts accessible to students of year 12. Using Mathematica students were able to visualise Fourier series of functions…

  9. The Air Gap Phenomenon in Children's Landscape Drawings.

    ERIC Educational Resources Information Center

    Hargreaves, David J.; And Others

    1981-01-01

    These studies confirm the view that the "air gap" phenomenon, which refers to the area that remains when ground and sky lines are constructed at the bottom and top of a drawing, is commonly found in the free drawings of middle and later childhood, but that it is readily abandoned when task demands are modified accordingly. (Author/DB)

  10. Evaluation of Communication about Groups: The Hydra Phenomenon.

    ERIC Educational Resources Information Center

    Desmond, Roger Jon; Bezzini, John

    A study investigated how the attribution of a problem solution to an individual or group affects the consumer's perception of the solution's quality. Based on the tendency to support group decision-making (Hydra phenomenon) it was predicted that decisions attributed to groups would be perceived as higher in quality than those made by individuals,…

  11. Collaboration in Education: The Phenomenon and Process of Working Together

    ERIC Educational Resources Information Center

    Goulet, Linda; Krentz, Caroline; Christiansen, Helen

    2003-01-01

    In this article we propose a model for collaboration in education. We begin by examining the roots of collaboration in consultation, collegiality, and cooperation. We then delineate the features of collaboration as phenomenon and process, offering the view that through talk, action, and reflection among individuals a community of learners emerges.…

  12. Phenomenon of mucous retention in the incisive canal.

    PubMed

    Keith, D A

    1979-11-01

    Mucous glands are rarely found in the anterior palate but may be observed in the incisive canal. A case history is presented of a lesion that resembled a nasopalatine cyst both clinically and radiographically but which was in fact an intra-bony extravasation phenomenon. PMID:290778

  13. The Making of a Cowboy: A High School Group Phenomenon.

    ERIC Educational Resources Information Center

    Serrano, Rodolfo G.

    A study focusing on the development and maintenance of peer groups was undertaken at South High School in the San Joaquin Valley (California). The central purpose of the study was to determine if a school culture existed at this school. Ethnographic and field observation methods were employed to examine the phenomenon of the "cowboys," a group of…

  14. Understanding the alternate bearing phenomenon: Resource budget model

    NASA Astrophysics Data System (ADS)

    Prasad, Awadhesh; Sakai, Kenshi

    2015-12-01

    We consider here the resource budget model of plant energy resources, which characterizes the ecological alternate bearing phenomenon in fruit crops, in which high and low yields occur in alternate years. The resource budget model is a tent-type map, which we study in detail. An infinite number of chaotic bands are observed in this map, which are separated by periodic unstable fixed points. These m bands chaotic attractors become m / 2 bands when the period-m unstable fixed points simultaneously collide with the chaotic bands. The distance between two sets of coexisting chaotic bands that are separated by a period-1 unstable fixed point is discussed. We explore the effects of varying a range of parameters of the model. The presented results explain the characteristic behavior of the alternate bearing estimated from the real field data. Effects of noise are also explored. The significance of these results to ecological perspectives of the alternate bearing phenomenon is highlighted.

  15. Self-Propelled Hovercraft Based on Cold Leidenfrost Phenomenon

    NASA Astrophysics Data System (ADS)

    Shi, Meng; Ji, Xing; Feng, Shangsheng; Yang, Qingzhen; Lu, Tian Jian; Xu, Feng

    2016-06-01

    The Leidenfrost phenomenon of liquid droplets levitating and dancing when placed upon a hot plate due to propulsion of evaporative vapor has been extended to many self-propelled circumstances. However, such self-propelled Leidenfrost devices commonly need a high temperature for evaporation and a structured solid substrate for directional movements. Here we observed a “cold Leidenfrost phenomenon” when placing a dry ice device on the surface of room temperature water, based on which we developed a controllable self-propelled dry ice hovercraft. Due to the sublimated vapor, the hovercraft could float on water and move in a programmable manner through designed structures. As demonstrations, we showed that the hovercraft could be used as a cargo ship or a petroleum contamination collector without consuming external power. This phenomenon enables a novel way to utilize programmable self-propelled devices on top of room temperature water, holding great potential for applications in energy, chemical engineering and biology.

  16. Results of an attempt to reproduce the STAP phenomenon.

    PubMed

    Aizawa, Shinichi

    2016-01-01

    In 2014, Obokata and colleagues reported their observation of a novel cell reprogramming phenomenon they named 'stimulus-triggered acquisition of pluripotency' (STAP). The most conclusive evidence for the pluripotency of so-called STAP cells was the purported ability of such cells to contribute to chimera formation. Here, I report the results of an attempt by Haruko Obokata to replicate the phenomenon under the supervision of the Scientific Validity Examination Team of RIKEN. In this follow-up study, putative STAP cells prepared by Haruko Obokata were injected into 1051 embryos, of which 591 were recovered. However, the injected cells made no significant contribution in any tissue in any of the embryos that developed. PMID:27610221

  17. Self-Propelled Hovercraft Based on Cold Leidenfrost Phenomenon

    PubMed Central

    Shi, Meng; Ji, Xing; Feng, Shangsheng; Yang, Qingzhen; Lu, Tian Jian; Xu, Feng

    2016-01-01

    The Leidenfrost phenomenon of liquid droplets levitating and dancing when placed upon a hot plate due to propulsion of evaporative vapor has been extended to many self-propelled circumstances. However, such self-propelled Leidenfrost devices commonly need a high temperature for evaporation and a structured solid substrate for directional movements. Here we observed a “cold Leidenfrost phenomenon” when placing a dry ice device on the surface of room temperature water, based on which we developed a controllable self-propelled dry ice hovercraft. Due to the sublimated vapor, the hovercraft could float on water and move in a programmable manner through designed structures. As demonstrations, we showed that the hovercraft could be used as a cargo ship or a petroleum contamination collector without consuming external power. This phenomenon enables a novel way to utilize programmable self-propelled devices on top of room temperature water, holding great potential for applications in energy, chemical engineering and biology. PMID:27338595

  18. Control of dynamic stall phenomenon for vertical axis wind turbine

    NASA Astrophysics Data System (ADS)

    Frunzulicǎ, Florin; Dumitrescu, Horia; Dumitrache, Alexandru; Suatean, Bogdan

    2013-10-01

    In the last years the wind turbine with vertical axis (VAWT) began to be more attractive due benefits in exploitation, the power range covering usually the domain 2 kW-20 kW. But, VAWTs suffer from many complicated aerodynamically problems, of which dynamic stall is an inherent phenomenon when they are operating at low values of tip speed ratio (TSR < 4), and this has a significant impact on vibration, noise, and power output of the VAWTs. For this reason, in the present work we perform a computational investigation of a two-dimensional dynamic stall phenomenon around a NACA0012 airfoil in oscillating motion at relative low Reynolds number (˜105). The unsteady flow is investigated numerically using RANS approach with two turbulence models (k-ω SST and transition SST). The same analysis was performed to evaluate three flow control methods: two passive and one active.

  19. Applying the big five personality factors to the impostor phenomenon.

    PubMed

    Bernard, Naijean S; Dollinger, Stephen J; Ramaniah, Nerella V

    2002-04-01

    The purpose of this study was to relate the impostor phenomenon (IP) to the Five-factor model of personality. A sample of 190 college students (79 men, 111 women) completed the Clance Impostor Phenomenon Scale (Clance, 1985), the Perceived Fradulence Scale (Kolligian & Sternberg, 1991), and the NEO-Personality Inventory-Revised (Costa & McCrae, 1992). Results of correlational and regression analyses support the predicted relations of imposter measures with high Neuroticism and low Conscientiousness. Facet-level correlations showed that depression and anxiety were particularly important characteristics of those with imposter feelings as well as low self-discipline and perceived competence. Implications for treatment and future research on the IP are discussed. PMID:12067196

  20. Control of resonance phenomenon in flexible structures via active support

    NASA Astrophysics Data System (ADS)

    Tavakolpour Saleh, A. R.; Mailah, M.

    2012-07-01

    This paper introduces the concept of active support to cope with the resonance phenomenon in the flexible structures. A valid computational platform for the flexible structure was first presented via a finite difference (FD) approach. Then, the active support mechanism was applied to the simulation algorithm through which the performance of the proposed methodology in suppressing the resonance phenomenon was evaluated. The flexible structure was thus excited with the external disturbance and the system response with and without the effect of the active support was investigated through a simulation study. The simulation outcomes clearly demonstrated effective resonance suppression in the flexible structure. Finally, an experimental rig was developed to investigate the validity of the proposed technique. The experimental results revealed an acceptable agreement with the simulation outcomes through which the validity of the proposed control method was affirmed.

  1. Results of an attempt to reproduce the STAP phenomenon

    PubMed Central

    Aizawa, Shinichi

    2016-01-01

    In 2014, Obokata and colleagues reported their observation of a novel cell reprogramming phenomenon they named ‘stimulus-triggered acquisition of pluripotency’ (STAP). The most conclusive evidence for the pluripotency of so-called STAP cells was the purported ability of such cells to contribute to chimera formation. Here, I report the results of an attempt by Haruko Obokata to replicate the phenomenon under the supervision of the Scientific Validity Examination Team of RIKEN. In this follow-up study, putative STAP cells prepared by Haruko Obokata were injected into 1051 embryos, of which 591 were recovered. However, the injected cells made no significant contribution in any tissue in any of the embryos that developed. PMID:27610221

  2. Understanding the alternate bearing phenomenon: Resource budget model.

    PubMed

    Prasad, Awadhesh; Sakai, Kenshi

    2015-12-01

    We consider here the resource budget model of plant energy resources, which characterizes the ecological alternate bearing phenomenon in fruit crops, in which high and low yields occur in alternate years. The resource budget model is a tent-type map, which we study in detail. An infinite number of chaotic bands are observed in this map, which are separated by periodic unstable fixed points. These m bands chaotic attractors become m/2 bands when the period-m unstable fixed points simultaneously collide with the chaotic bands. The distance between two sets of coexisting chaotic bands that are separated by a period-1 unstable fixed point is discussed. We explore the effects of varying a range of parameters of the model. The presented results explain the characteristic behavior of the alternate bearing estimated from the real field data. Effects of noise are also explored. The significance of these results to ecological perspectives of the alternate bearing phenomenon is highlighted. PMID:26723141

  3. Rumpel-Leede Phenomenon in a Hypertensive Lady on Amlodipine

    PubMed Central

    Viswanathan, Stalin

    2014-01-01

    We are describing a 60-year-old hypertensive lady who developed Rumpel-Leede phenomenon following the use of a tourniquet to obtain a blood sample. History revealed that she was on amlodipine therapy and that spontaneous sun-exposure related purpura was often seen since amlodipine was prescribed. Examinations and investigations provided normal results. She refused consent for a skin biopsy. Symptoms resolved after its substitution with enalapril and dihydrochlorothiazide, without any further recurrence. PMID:24959504

  4. The melting phenomenon in random-walk model of DNA

    SciTech Connect

    Hayrapetyan, G. N.; Mamasakhlisov, E. Sh.; Papoyan, Vl. V.; Poghosyan, S. S.

    2012-10-15

    The melting phenomenon in a double-stranded homopolypeptide is considered. The relative distance between the corresponding monomers of two polymer chains is modeled by the two-dimensional random walk on the square lattice. Returns of the random walk to the origin describe the formation of hydrogen bonds between complementary units. To take into account the two competing interactions of monomers inside the chains, we obtain a completely denatured state at finite temperature T{sub c}.

  5. Correlates of the impostor phenomenon among undergraduate entrepreneurs.

    PubMed

    Sightler, K W; Wilson, M G

    2001-06-01

    The impostor phenomenon describes the self-attribution of success to luck and interpersonal skills rather than to intelligence and ability, despite external validation to the contrary. Evidence suggests the presence of impostor characteristics among a group of 63 undergraduate entrepreneurs. More intense impostor feelings were associated with an external locus of control and a stronger perceived effect of work on family life. Implications for entrepreneurial performance are discussed and questions for research are presented. PMID:11508002

  6. The E-Book Phenomenon: A Disruptive Technology

    ERIC Educational Resources Information Center

    Wilson, T. D.

    2014-01-01

    Introduction: The e-book and its associated technology have emerged as a disruptive technology over the past ten years. The aim of this paper is to discuss some of the consequences of this development, based on the work of the e-books in Sweden research projects. Argument: To explain the impact of the e-book phenomenon we use Winston's theory…

  7. Threshold energy for sub-barrier fusion hindrance phenomenon

    NASA Astrophysics Data System (ADS)

    Sargsyan, V. V.; Adamian, G. G.; Antonenko, N. V.; Scheid, W.; Zhang, H. Q.

    2013-02-01

    The relationship between the threshold energy for a deep sub-barrier fusion hindrance phenomenon and the energy at which the regime of interaction changes (the turning-off of the nuclear forces and friction) in the sub-barrier capture process is studied within the quantum diffusion approach. The quasielastic barrier distribution is shown to be a useful tool to clarify whether the slope of capture cross section changes at sub-barrier energies.

  8. Life as a planetary phenomenon: the colonization of Mars

    NASA Technical Reports Server (NTRS)

    Margulis, L.; Guerrero, R.

    1995-01-01

    Life is a planet-wide phenomenon in which its components incessantly move and interact. Life imperatively recycles its parts at the surface of the Earth in a chemical transformation and physical transport that depends utterly on the energy from a recent star, the Sun. Humanity, entirely dependent on other beings, plays a recent and relatively small part in the great phenomenon of life that transports and transforms the surface of the Earth. Our species accelerates but does not dominate the metabolism of the Earth system. Ironically, during the Apollo days of the sixties, fears were rampant that Martian or other extraterrestrial "germs" might "contaminate" our planet. After Viking, such fears are seen as the manifestation of cultural paranoia. The Viking missions complemented ground-based astronomical observation and yielded definitive evidence for the lack of life on the red planet. The Gaia hypothesis states that the surface temperature, composition of the reactive gases, oxidation state, alkalinity-acidity on today's Earth are kept homeorrhetically at values set by the sum of the activities of the current biota. Life, in other words, not only produces and maintains its immediate environment, but appears on Earth only as a planetary phenomenon. Since the natural tendency of all life is to grow exponentially to fill proximal volume, the question now "can life ecopoietically expand to Mars?" is entirely equivalent to the query of "can Gaia reproduce?".

  9. Life as a planetary phenomenon: the colonization of Mars.

    PubMed

    Margulis, L; Guerrero, R

    1995-01-01

    Life is a planet-wide phenomenon in which its components incessantly move and interact. Life imperatively recycles its parts at the surface of the Earth in a chemical transformation and physical transport that depends utterly on the energy from a recent star, the Sun. Humanity, entirely dependent on other beings, plays a recent and relatively small part in the great phenomenon of life that transports and transforms the surface of the Earth. Our species accelerates but does not dominate the metabolism of the Earth system. Ironically, during the Apollo days of the sixties, fears were rampant that Martian or other extraterrestrial "germs" might "contaminate" our planet. After Viking, such fears are seen as the manifestation of cultural paranoia. The Viking missions complemented ground-based astronomical observation and yielded definitive evidence for the lack of life on the red planet. The Gaia hypothesis states that the surface temperature, composition of the reactive gases, oxidation state, alkalinity-acidity on today's Earth are kept homeorrhetically at values set by the sum of the activities of the current biota. Life, in other words, not only produces and maintains its immediate environment, but appears on Earth only as a planetary phenomenon. Since the natural tendency of all life is to grow exponentially to fill proximal volume, the question now "can life ecopoietically expand to Mars?" is entirely equivalent to the query of "can Gaia reproduce?" PMID:11539563

  10. Perspectives of biotechnologies based on dormancy phenomenon for space researches

    NASA Astrophysics Data System (ADS)

    Alekseev, V.; Sychev, V.; Layus, D.; Levinsky, M.; Novikova, N.; Zakhodnova, T.

    Long term space missions will require a renewable source of food and an efficient method to recycle oxygen Plants especially aquatic micro algae provide an obvious solution to these problems However long duration plant growth and reproduction in space that is necessary for transportation of a control ecological life support system CELSS from Earth to other planets are problematic The introduction of heterotrophs in space CELSS is a more formidable problem as the absence of gravity creates additional difficulties for their life Dormancy phenomenon protected a great many animals and plants in harsh environmental conditions within a special resting phases of life cycle lasting from months up to hundred years This phenomenon can be quite perspective as a tool to overcome difficulties with CELSS transportation in space missions Cryptobiotic stages of microbes fungi unicellular algae and protists can survive in open space conditions that is important for interplanetary quarantine and biological security inside spacecraft Searching for life outside the Earth at such planet like Mars with extremely variable environment should be oriented on dormancy as crucial phases of a life cycle in such organisms Five major research programs aimed on study dormancy phenomenon for exobiology purposes and creation of new biotechnologies are discussed List of species candidate components of CELSS with dormancy in their life cycle used in space experiments at the Russian segment of International Space Station now includes 26 species from bacteria to fish The

  11. The genetic equidistance phenomenon at the proteomic level.

    PubMed

    Luo, Denghui; Huang, Shi

    2016-07-01

    The field of molecular evolution started with the alignment of a few protein sequences in the early 1960s. Among the first results found, the genetic equidistance result has turned out to be the most unexpected. It directly inspired the ad hoc universal molecular clock hypothesis that in turn inspired the neutral theory. Unfortunately, however, what is only a maximum distance phenomenon was mistakenly transformed into a mutation rate phenomenon and became known as such. Previous work studied a small set of selected proteins. We have performed proteome wide studies of 7 different sets of proteomes involving a total of 15 species. All 7 sets showed that within each set of 3 species the least complex species is approximately equidistant in average proteome wide identity to the two more complex ones. Thus, the genetic equidistance result is a universal phenomenon of maximum distance. There is a reality of constant albeit stepwise or discontinuous increase in complexity during evolution, the rate of which is what the original molecular clock hypothesis is really about. These results provide additional lines of evidence for the recently proposed maximum genetic diversity (MGD) hypothesis. PMID:26973320

  12. Exploration of the e-patient phenomenon in nursing informatics.

    PubMed

    Gee, Perry M; Greenwood, Deborah A; Kim, Katherine K; Perez, Susan L; Staggers, Nancy; DeVon, Holli A

    2012-01-01

    The availability of health information on the Internet has equalized opportunities for knowledge between patients and their health care providers, creating a new phenomenon called the e-patient. E-patients use technology to actively participate in their health care and assume higher levels of responsibility for their own health and wellness. This phenomenon has implications for nursing informatics research related to e-patients and potential collaboration with practitioners in developing a collective wisdom. Nursing informatics can use the data, information, knowledge, and wisdom (DIKW) framework to understand how e-patients and clinicians may achieve this collective wisdom. Nurse informaticists can use constructivism and Gadamerian hermeneutics to bridge each stage of this framework to illustrate the fundamentals of patient and clinician interactions and commonality of language to achieve a collective wisdom. Examining the e-patient phenomenon will help nurse informaticists evaluate, design, develop, and determine the effectiveness of information systems used by e-patients. The Internet can facilitate a partnership between the patient and clinician and cultivate a collective wisdom, enhanced by collaboration between nurse informatics and e-patients. PMID:22221955

  13. Identifying Mechanisms Behind the Tullio Phenomenon: a Computational Study Based on First Principles.

    PubMed

    Grieser, Bernhard J; Kleiser, Leonhard; Obrist, Dominik

    2016-04-01

    Patients with superior canal dehiscence (SCD) suffer from events of dizziness and vertigo in response to sound, also known as Tullio phenomenon (TP). The present work seeks to explain the fluid-dynamical mechanisms behind TP. In accordance with the so-called third window theory, we developed a computational model for the vestibular signal pathway between stapes and SCD. It is based on first principles and accounts for fluid-structure interactions arising between endolymph, perilymph, and membranous labyrinth. The simulation results reveal a wave propagation phenomenon in the membranous canal, leading to two flow phenomena within the endolymph which are in close interaction. First, the periodic deformation of the membranous labyrinth causes oscillating endolymph flow which forces the cupula to oscillate in phase with the sound stimulus. Second, these primary oscillations of the endolymph induce a steady flow component by a phenomenon known as steady streaming. We find that this steady flow of the endolymph is typically in ampullofugal direction. This flow leads to a quasi-steady deflection of the cupula which increases until the driving forces of the steady streaming are balanced by the elastic reaction forces of the cupula, such that the cupula attains a constant deflection amplitude which lasts as long as the sound stimulus. Both response types have been observed in the literature. In a sensitivity study, we obtain an analytical fit which very well matches our simulation results in a relevant parameter range. Finally, we correlate the corresponding eye response (vestibulo-ocular reflex) with the fluid dynamics by a simplified model of lumped system constants. The results reveal a "sweet spot" for TP within the audible sound spectrum. We find that the underlying mechanisms which lead to TP originate primarily from Reynolds stresses in the fluid, which are weaker at lower sound frequencies. PMID:26883248

  14. Allergic reactions, "spillover' reactions, and T-cell subsets.

    PubMed

    Bruynzeel, D P; Nieboer, C; Boorsma, D M; Scheper, R J; van Ketel, W G

    1983-01-01

    A strong positive, allergic patch-test reaction was elicited in 15 patients with an established allergy for a particular allergen. Patches with a marginally irritating concentration of sodium lauryl sulfate (SLS) were applied at fixed distances. The SLS patch situated adjacent to the allergic reaction was significantly enhanced in 12 of 15 patients (P less than 0.01) compared to more distant SLS reactions ("spillover'). Only quantitative differences were observed in the histologic pictures of the different types of reaction. The infiltrate consisted of lymphocytes and histiocytes, mainly located perivascular in the upper dermis. T-cell subsets were assessed with monoclonal antibodies using an immunoperoxidase technique. The distribution of the different T cells was the same for both reaction types. T cells located outside the perivascular infiltrates (e.g., in the epidermal vesicles) were OKT-8-positive (cytotoxic/suppressor T lymphocytes). Immunofluorescence examination did not show different patterns for the allergic or "enhanced toxic' reactions with regard to the presence of immunoglobulins and complement. The "spillover' phenomenon may cause false-positive patch-test reactions. PMID:6223603

  15. On phenomenon of light radiation from miniature balls immersed in water

    NASA Astrophysics Data System (ADS)

    Torchigin, V. P.; Torchigin, A. V.

    2010-01-01

    A phenomenon of light radiation from miniature silicon balls produced at arc discharge and immersed in water is described. Video film showing shining balls in a vessel with water is presented. An explanation of this phenomenon is considered. Similarities and differences of this phenomenon with a phenomenon of ball lightning are analyzed.

  16. Splendore-Hoeppli phenomenon in a cat with osteomyelitis caused by Streptococcus species.

    PubMed

    França, Silvia de Araujo; Braga, Juliana Fortes Vilarinho; Moreira, Matheus Vilardo Loes; Silva, Vitor Cesar Martins; Souza, Erick Ferry; Pereira, Luiz Carlos; Rezende, Cleuza Maria de Faria; Ecco, Roselene

    2014-02-01

    A 9-month-old male neutered mixed-breed cat had a history of chronic lameness of the right hind limb, which was non-responsive to antibiotic treatment. Hematologic analysis revealed marked neutrophilia and mild monocytosis. Radiography revealed extensive loss of cortical bone, and replacement with irregular and disorganized bone. There was loss of the normal cortico-medullary distinction, and the medullary cavity had an irregular radiodensity suggestive of osteomyelitis. Surgical curettage and antibiotics did not improve the clinical condition, and amputation was performed. Grossly, the skin over the right tibia was ulcerated with a viscous and granular exudate. At histopathology, there was marked diffuse pyogranulomatous dermatitis, myositis, periostitis and osteomyelitis associated with Splendore-Hoeppli phenomenon. In addition, there was marrow osteoproliferation and multifocal cortical loss, reabsorption, fibroplasia and endosteal bone formation. Gram staining revealed myriad slightly elongated Gram-positive bacteria, arranged in pairs or single chains, confirmed by polymerase chain reaction as Streptococcus species. PMID:23906707

  17. [The comfort of a pleasant discomfort. Humour as a biological phenomenon I].

    PubMed

    Raab, Thomas

    2008-12-15

    No understanding of the nature of humour can be complete without a description of the emotional reactions and mechanisms accompanying humour. The enjoyment of a good laugh is essential to an explanation of humour and the reason why we seek humorous experiences. Humour is, however, not only coupled with positive emotions, but also triggered by potentially harmful experiences. In this regard, humour can best be described as the experience of something potentially harmful in a safe (social) context. Humour, seen as a biological phenomenon, therefore has its evolutionary roots in the mechanisms underlying the ability to learn to avoid danger. In humans this often takes place in a complex social context, and the final steps in the evolution of humour therefore must be sought in the complex primate society. In this, the first of two articles on humour in a biological context, we examine the role of emotions in experiencing humour. PMID:19128547

  18. Analysis of Ares Crew Launch Vehicle Transonic Alternating Flow Phenomenon

    NASA Technical Reports Server (NTRS)

    Sekula, Martin K.; Piatak, David J.; Rausch, Russ D.

    2012-01-01

    A transonic wind tunnel test of the Ares I-X Rigid Buffet Model (RBM) identified a Mach number regime where unusually large buffet loads are present. A subsequent investigation identified the cause of these loads to be an alternating flow phenomenon at the Crew Module-Service Module junction. The conical design of the Ares I-X Crew Module and the cylindrical design of the Service Module exposes the vehicle to unsteady pressure loads due to the sudden transition between a subsonic separated and a supersonic attached flow about the cone-cylinder junction as the local flow randomly fluctuates back and forth between the two flow states. These fluctuations produce a square-wave like pattern in the pressure time histories resulting in large amplitude, impulsive buffet loads. Subsequent testing of the Ares I RBM found much lower buffet loads since the evolved Ares I design includes an ogive fairing that covers the Crew Module-Service Module junction, thereby making the vehicle less susceptible to the onset of alternating flow. An analysis of the alternating flow separation and attachment phenomenon indicates that the phenomenon is most severe at low angles of attack and exacerbated by the presence of vehicle protuberances. A launch vehicle may experience either a single or, at most, a few impulsive loads since it is constantly accelerating during ascent rather than dwelling at constant flow conditions in a wind tunnel. A comparison of a windtunnel- test-data-derived impulsive load to flight-test-data-derived load indicates a significant over-prediction in the magnitude and duration of the buffet load. I. Introduction One

  19. Modeling the Pineapple Express phenomenon via Multivariate Extreme Value Theory

    NASA Astrophysics Data System (ADS)

    Weller, G.; Cooley, D. S.

    2011-12-01

    The pineapple express (PE) phenomenon is responsible for producing extreme winter precipitation events in the coastal and mountainous regions of the western United States. Because the PE phenomenon is also associated with warm temperatures, the heavy precipitation and associated snowmelt can cause destructive flooding. In order to study impacts, it is important that regional climate models from NARCCAP are able to reproduce extreme precipitation events produced by PE. We define a daily precipitation quantity which captures the spatial extent and intensity of precipitation events produced by the PE phenomenon. We then use statistical extreme value theory to model the tail dependence of this quantity as seen in an observational data set and each of the six NARCCAP regional models driven by NCEP reanalysis. We find that most NCEP-driven NARCCAP models do exhibit tail dependence between daily model output and observations. Furthermore, we find that not all extreme precipitation events are pineapple express events, as identified by Dettinger et al. (2011). The synoptic-scale atmospheric processes that drive extreme precipitation events produced by PE have only recently begun to be examined. Much of the current work has focused on pattern recognition, rather than quantitative analysis. We use daily mean sea-level pressure (MSLP) fields from NCEP to develop a "pineapple express index" for extreme precipitation, which exhibits tail dependence with our observed precipitation quantity for pineapple express events. We build a statistical model that connects daily precipitation output from the WRFG model, daily MSLP fields from NCEP, and daily observed precipitation in the western US. Finally, we use this model to simulate future observed precipitation based on WRFG output driven by the CCSM model, and our pineapple express index derived from future CCSM output. Our aim is to use this model to develop a better understanding of the frequency and intensity of extreme

  20. Hysteresis phenomenon in the galloping oscillation of a square cylinder

    NASA Astrophysics Data System (ADS)

    Luo, S. C.; Chew, Y. T.; Ng, Y. T.

    2003-08-01

    It is well known that a square cylinder with one side normal to a uniform stream will gallop when a critical flow velocity is exceeded. It is also quite well known that there is a hysteresis phenomenon in the variation of the cylinder's galloping amplitude with the flow velocity. However, little is known about the cause of this hysteresis phenomenon, and the objective of this paper is to study it more closely. In the present study, flow over a stationary square cylinder at different angle of attack (/α) and at Reynolds number (Re) of 250 and 1000 was investigated numerically by using a 2-D hybrid vortex computation scheme. The study reveals that the well known point of inflection which exists in the side force (Cy) versus /α plots at high Reynolds number only occurs at Re=1000, /α=4° in the present numerical simulation. Nonlinear analysis further reveals that this point of inflection is the cause of the hysteresis phenomenon. By further analysing the computed flow field, it is noted that at Re=1000, /α=4°, intermittent flow reattachment takes place at alternate vortex shedding cycle on one side of the cylinder. This results in larger side force fluctuation, and it is conjectured that such large side force fluctuation affects the increasing trend of the side force with angle of attack, resulting in the point of inflection reported earlier. The above-mentioned alternate cycle flow reattachment was much less prominent at /α=2° and 6° (Re=1000), and was not observed at Re=250. Finally, dye flow visualization was carried out in a recirculating water tunnel and the results at Re=1000 confirms the existence of the intermittent flow reattachment. However, in the experiment, flow reattachment does not take place in a very regular alternate cycle manner as in the computation. Instead, it occurs intermittently, possibly due to three-dimensional effects in real flow.

  1. Drug Reactions

    MedlinePlus

    Most of the time, medicines make our lives better. They reduce aches and pains, fight infections, and control problems such as high blood pressure or diabetes. But medicines can also cause unwanted reactions. One problem is ...

  2. Wigner's Changing View of the Elementary Quantum Phenomenon

    NASA Astrophysics Data System (ADS)

    Wheeler, John Archibald

    2002-04-01

    In 1961, Eugene Wigner argued that "the being with a consciousness must have a different role in quantum mechanics than the inanimate measuring device." By 1981, he had changed to a totally different position, one compatible with the position of Niels Bohr, that all it requires for the elementary quantum phenomenon is an elementary process brought to a close by an irreversible act of amplification (i.e. the click of a counter or the blackening of a grain of photographic emulsion.) It is instructive to review the reasons Wigner gives for this important change in his views.

  3. Multiple-resonance phenomenon in neutrinoless double-electron capture

    SciTech Connect

    Eliseev, S.; Goncharov, M.; Blaum, K.; Block, M.; Herfurth, F.; Minaya Ramirez, E.; Droese, C.; Schweikhard, L.; Novikov, Yu. N.; Shabaev, V. M.; Tupitsyn, I. I.; Zubova, N. A.; Zuber, K.

    2011-07-15

    A superposition of multiple resonance states in neutrinoless double-electron capture in {sup 156}Dy has been discovered. Penning-trap mass spectrometry has been used for atomic-mass-difference measurements and careful calculations of electron wave functions and double-hole binding energies have been performed to determine the resonance-enhancement factors. Transitions to four nuclear excited states in the daughter nuclide {sup 156}Gd have been identified as resonantly enhanced, including one with a full resonant enhancement, within the uncertainty of 100 eV. This phenomenon is unique in that it can be used to probe the mechanisms of neutrinoless processes.

  4. Editorial Commentary: The Pivot-Shift Phenomenon Is Multifactorial.

    PubMed

    Fu, Freddie H; Herbst, Elmar

    2016-06-01

    The biomechanical study on the role of the anterior cruciate ligament and anterolateral structures in controlling internal tibial rotation has some major limitations: creation of a large injury to the anterolateral structures, examination only at 30° of flexion, only one outcome variable (internal rotation), and no application of different combined forces. This "worst-case scenario" does not represent the typical injury pattern, and therefore the results might overestimate the influence of these structures on rotatory laxity. Essentially, the pivot-shift phenomenon is multifactorial and injuries or insufficiency of the anterolateral structures are only one explanation. PMID:27263764

  5. Bacterial resistance to antimicrobial peptides: an evolving phenomenon.

    PubMed

    Fleitas, Osmel; Agbale, Caleb M; Franco, Octavio L

    2016-01-01

    Bacterial resistance to conventional antibiotics is currently a real problem all over the world, making novel antimicrobial compounds a real research priority. Some of the most promising compounds found to date are antimicrobial peptides (AMPs). The benefits of these drugs include their broad spectrum of activity that affects several microbial processes, making the emergence of resistance less likely. However, bacterial resistance to AMPs is an evolving phenomenon that compromises the therapeutic potential of these compounds. Therefore, it is mandatory to understand bacterial mechanisms of resistance to AMPs in depth, in order to develop more powerful AMPs that overcome the bacterial resistance response. PMID:27100488

  6. [Psoriasis migrans : Erythema migrans as Koebner phenomenon in psoriasis].

    PubMed

    Ständer, S; Ständer, M; Thomas, P; Prinz, J C; Wolf, R

    2016-07-01

    Psoriasis is a chronic inflammatory disorder of the epidermis, which can be induced by systemic factors, such as streptococci infections or drugs. In addition, psoriasis can be caused by a local cutaneus trauma, known as Koebner phenomenon. Here, we describe a woman with psoriasis in remission, who developed a new psoriatic lesion due to a cutaneous infection with Borrelia burgdorferi. After causal therapy with doxycycline, the erythema migrans and psoriasis lesions disappeared. PMID:27106503

  7. On the folding phenomenon of comet tail rays

    NASA Astrophysics Data System (ADS)

    Ershkovich, A. I.

    1982-01-01

    It is shown that the folding phenomenon of the comet tail rays is compatible with the Ferraro isorotation law if the comet tail magnetic field has no azimuthal component, that is, Bphi (the polar angle) equals zero. Considering electric drift due to convectional electric fields, a formula is obtained for the angular rate of a ray closure which reduces to that of Ness and Donn (1966) if the velocity profile across the tail is linear. The magnetic field B of approximately 20-40 gammas in the coma and less than about 10 gammas in the distant tail is estimated under typical solar wind conditions at 1 AU.

  8. Reaction profiles in porous electrodes. Final report

    SciTech Connect

    Katan, T.; Carlen, P.J.

    1985-05-01

    An experimental program was conducted to ascertain causes of alkaline zinc electrode shape change and to determine the development of reaction profiles within the pores of porous zinc electrodes. Various analog electrochemical cells were operated to isolate and evaluate the individual processes occurring during charge and discharge. It was found that both edge effects and osmosis can be responsible for the shape change phenomenon.

  9. Fatigue in psoriasis: a phenomenon to be explored.

    PubMed

    Skoie, I M; Ternowitz, T; Jonsson, G; Norheim, K; Omdal, R

    2015-01-01

    Fatigue is a prevalent and substantial phenomenon in many patients with chronic inflammatory diseases, often rated by patients as the most troublesome symptom and aspect of their disease. It frequently interferes with physical and social functions and may lead to social withdrawal, long-standing sick leave and disability. Although psychological and somatic factors such as depression, sleep disorders, pain and anaemia influence fatigue, the underlying pathophysiological mechanisms by which fatigue is generated and regulated are largely unknown. Increasing evidence points towards a genetic and molecular basis for fatigue as part of the innate immune system and cellular stress responses. Few studies have focused on fatigue in dermatological diseases. Most of these studies describe fatigue as a phenomenon related to psoriatic arthritis and describe the beneficial effects of biological agents on fatigue observed in clinical studies. It is therefore possible that this problem has been underestimated and deserves more attention in the dermatological community. In this review, we provide a definition and explanation for chronic fatigue, describe some commonly used instruments for measuring fatigue, and present hypothetical biological mechanisms with an emphasis on activation of the innate immune system and oxidative stress. An overview of relevant clinical studies covering the theme 'psoriasis and fatigue' is given. PMID:25557165

  10. Night vision goggle luminance disparity and the Pulfrich phenomenon

    NASA Astrophysics Data System (ADS)

    Pinkus, Alan; Task, Harry L.

    2004-09-01

    When night vision goggle (NVG) image intensifier tubes (I2Ts) are replaced during maintenance, the output luminances of the two channels must not exceed a ratio of 1.5 (brighter channel luminance divided by the dimmer channel luminance) in order to meet the current allowed binocular luminance disparity specification. Two studies were performed to investigate the validity of this requirement. The first study estimated thresholds of binocular luminance disparity detection for observers looking through NVGs. For eight observers, the 25% corrected-for-chance probability of detecting an ocular luminance difference, yielded an average ratio of 1.43 indicating that the current 1.5 specification is perhaps too loose. The second study investigated the Pulfrich phenomenon, a pseudo-stereo effect that can be induced by presenting luminance imbalances to the eyes. This study created NVG luminance imbalances using neutral density (ND) filters and then investigated whether or not the various imbalance levels were sufficient to cause the Pulfrich phenomenon to be perceived. Results indicated an imbalance ratio of 1.10 was insufficient to cause the effect to be seen, but a ratio of 1.26 was sufficient (p <= 0.0003) for the effect to be seen, at least part of the time. Based on these results, it is apparent the allowed binocular luminance disparity ratio should probably be tightened to at least 1.3 with a goal of 1.2.

  11. A lactogenic-immune-deficiency-syndrome in cows: unexplained phenomenon.

    PubMed

    Brenner, J; Neria, A; Askenazy, G; Paz, R; Meirom, R; Ungar-Waron, H; Trainin, Z

    1992-05-01

    The majority of adult cows in a certain dairy herd, were found to have very low levels of immunoglobulins (Igs) in their colostrum. This phenomenon was defined by us as Lactogenic-Immune-Deficiency-Syndrome (LIDS). The mean IgG levels were 44.5 and 57.2 mg ml-1 respectively (on two different occasions) as compared to that of a control group which was 103.4 mg ml-1. The levels of Igs in the colostra of heifers from the same herd were found to be higher than those of adult cows. The degree of LIDS was found to be closely related to the age of cows in the herd. The low levels of Igs in the colostra were not directly linked to their concentrations in the sera of the affected cows. The relatively low amount of IgA in the affected colostra suggests that the local production in the lymph tissue associated with the mammary glands is impaired as well. In order to investigate the etiology of the phenomenon, tests were carried out to reveal whether bovine leucosis virus (BLV) infection or immune complexes were involved in the pathogenesis of LIDS. The results were negative. The etiology of LIDS remains for the time being unknown. PMID:1632067

  12. Surface plasmon resonance phenomenon of the insulating state polyaniline

    SciTech Connect

    Umiati, Ngurah Ayu Ketut; Triyana, Kuwat; Kamsul

    2015-04-16

    Surface Plasmon Resonance (SPR) phenomenon of the insulating polyaniline (PANI) is has been observed. Surface Plasmon (SP) is the traveled electromagnetic wave that passes through the interface of dielectric metal and excited by attenuated total reflection (ATR) method in Kretschmannn configuration (Au-PANI prism). The resonance condition is observed through the angle of SPR in such condition that SP wave is coupled by the evanescent constant of laser beam. In this research, the laser beam was generated by He–Ne and its wavelength (λ) was 632,8 nm. SPR curve is obtained through observation of incidence angles of the laser beam in prism. SPR phenomenon at the boundary between Au – PANI layer has showed by reflection dip when the laser beam passes through the prism. In this early study, the observation was carried out through simulation Winspall 3.02 software and preliminary compared with some experimental data reported in other referred literatures. The results shows that the optimum layer of Au and polyaniline are 50 and 1,5 nm thick respectively. Our own near future experimental work would be further performed and reported elsewhere.

  13. Investigation of the unstable flow phenomenon in a pump turbine

    NASA Astrophysics Data System (ADS)

    Yin, JunLian; Wang, DeZhong; Walters, D. Keith; Wei, XianZhu

    2014-06-01

    Instability of pump turbine with S-shaped curve is characterized by large fluctuations of rotational speed during the transient processes. For investigating this phenomenon, a numerical model based on the dynamic sliding mesh method (DSSM) is presented and used to numerically solve the 3D transient flow which is characterized by the variable rotation speed of runner. The method is validated by comparison with measured data for a load rejection process in a prototype pump turbine. The results show that the calculated rotation speed agrees well with the experimental data. Based on the validated model, simulations were performed for the runaway process using an artificially assumed operating condition under which the unstable rotation speed is expected to appear. The results confirm that the instability of runner rotational speed can be effectively captured with the proposed method. Presented results include the time history profiles of unit flow rate and unit rotating speed. The internal flow characteristics in a typical unstable period are discussed in detail and the mechanism of the unstable hydraulic phenomenon is explained. Overall, the results suggest that the method presented here can be a viable alternative to predict the dynamic characteristics of pump turbines during transient processes.

  14. Biology of the twinning phenomenon: embryogenesis and teratogenesis.

    PubMed

    Lutz, H

    1976-01-01

    The twinning phenomenon has always interested the great public, the artists, and naturally the scientists. Isidore Geoffroy St. Hilaire has established a classification still now valid. This classification considers the different types of double monsters which are found in nature in all classes of vertebrates, including man. To explain the twinning phenomenon, the experimental realizations have progressed by successive bounds after the preliminary attempts of different authors. Now, when it is question of experimental duplication, anybody thinks of Speman for the amphibians, of Lutz for the birds, of Seidel for the rabbit, and of Tarkowsky for the mouse. Now, it is possible to conceive a twinning resulting from the separation of the first blastomeres (amphibian, rabbit, mouse) and a twinning originating from the fissuration of the blastoderm (bird, mammal). All these experiments confirm the unicist-theory. If a total or partial regulation of the excedents may be experimentally realized, no argument can however support this theory in the realization of the double monstrosity. PMID:801414

  15. [The knowledge of animal respiration as a combustion phenomenon].

    PubMed

    de Micheli, Alfredo

    2014-01-01

    The different stages leading to knowledge of the phenomenon of animal breathing are going from some writings in Corpus Hippocraticum to Aristoteles' and Galen's works, who considered the heart as the source of the animal heat. Later, Miguel Servet suggested that the inspired air can achieve other functions besides cooling the blood. After that, different explications of the animal heat were raised. About 1770, due to progress of knowledge in the chemistry field, first Mayow and later Black began to consider the animal respiration as a combustion. The important treatise Méthode de nomenclature chimique, published by Guyton de Morveau et al. in 1787 and soon after the Traité élémentaire de chimie de Lavoisier (1789) provided a solid support to Lavoisier's thought. This way on arrived to consider analogous the respiration and combustion phenomena. Studies on the animal respiration phenomenon continued in xix century and in the following century it was possible to apply thermodynamic principles to biology: "generalized thermodynamics". PMID:25097147

  16. String tightening as a self-organizing phenomenon.

    PubMed

    Banerjee, Bonny

    2007-09-01

    The phenomenon of self-organization has been of special interest to the neural network community throughout the last couple of decades. In this paper, we study a variant of the self-organizing map (SOM) that models the phenomenon of self-organization of the particles forming a string when the string is tightened from one or both of its ends. The proposed variant, called the string tightening self-organizing neural network (STON), can be used to solve certain practical problems, such as computation of shortest homotopic paths, smoothing paths to avoid sharp turns, computation of convex hull, etc. These problems are of considerable interest in computational geometry, robotics path-planning, artificial intelligence (AI) (diagrammatic reasoning), very large scale integration (VLSI) routing, and geographical information systems. Given a set of obstacles and a string with two fixed terminal points in a 2-D space, the STON model continuously tightens the given string until the unique shortest configuration in terms of the Euclidean metric is reached. The STON minimizes the total length of a string on convergence by dynamically creating and selecting feature vectors in a competitive manner. Proof of correctness of this anytime algorithm and experimental results obtained by its deployment have been presented in the paper. PMID:18220194

  17. The McGurk phenomenon in Italian listeners

    PubMed Central

    Bovo, R; Ciorba, A; Prosser, S; Martini, A

    2009-01-01

    Summary In the classic example of the McGurk effect, when subjects see a speaker say /ga/ and hear a simultaneous /ba/, they typically perceive /da/, a syllable that was not presented either acoustically, or visually. This phenomenon, although non-natural and recreated in laboratory investigations, has been studied in order to better understand how, where and when the central nervous system processes and integrates visual and auditory signals. Till now, it has been demonstrated for English, Spanish and German languages, while in Japanese and Chinese it seems weaker. Aim of this study was to evaluate the entity of the McGurk effect for the Italian language. Results obtained demonstrate a robust McGurk effect for the Italian language, which has never been described before. The phenomenon is highly significant when an auditory bilabial Consonant-Vowel is dubbed with a visual apico-dental or velar Consonant-Vowel. Results are discussed on the basis of the recent hypothesis regarding the bimodal perception. PMID:20161878

  18. Investigation of the Entrainment Phenomenon Using a Scaling Approach

    NASA Astrophysics Data System (ADS)

    Kishore, Aravind; Ghia, Urmila

    2014-11-01

    Air entrainment is a commonly observed phenomenon; we see it when filling a glass with water from a faucet, in the frothing of the ocean surface, in white water rapids, etc. The focus of our work is the numerical simulation of the entrainment phenomenon associated with laminar plunging jets. With increasing jet velocity, the interfacial cusp formed between the jet and the liquid pool becomes sharper. At a critical jet velocity, entrainment inception occurs, i.e., the interfacial cusp breaks, the interface ruptures, and air is pulled into the liquid pool. We conduct two-fluid simulations using the Volume-Of-Fluid (VOF) methodology. The large range of length scales in the flow presents a major computational challenge. We postulate an approach based on scaling of the underlying physics and this helps alleviate the constraints that the physics poses on the numerical method. The approach is validated using a simple flow configuration - a cylinder rotating at an interface between two fluids. Our simulations capture the sharpening of the interfacial cusp, and the sudden rupture of the interface. The predicted critical entrainment velocities are within 1% of experimental data, thereby providing confidence in the approach. This work was supported by the UC Simulation Center at the University of Cincinnati.

  19. a Study of Ricochet Phenomenon for Inclined Impact of Projectile

    NASA Astrophysics Data System (ADS)

    Jo, Jong-Hyun; Lee, Young-Shin

    In this study, the numerical simulation using AUTODYN-3D program was investigated for trajectory prediction for inclined impacts of projectiles. The penetration and perforation of polycarbonate(PC) plate by 7.62 mm projectile was investigated numerically. The characteristic structure of the projectile's trajectory in the PC plates was studied. Two combined failure criteria were used in the target plate, and the target plate was modeled with the properties of polycarbonate for simulating the ricochet phenomenon. The numerical analyses were used to study the effect of the angle of inclination on the trajectory and kinetic energy of the projectile. The dynamic deformation behaviors tests of PC were compared with numerical simulation results which can be used for predictive purpose. Ricochet phenomenon for angles of inclination of 0° ≤ θ ≤ 20° in the analysis. The projectile perforated the plate for θ > 30°, thus defined a failure envelope for numerical configuration. The numerical analyses was used to study the effect under the projectile impact velocity on the depth of penetration(DOP).

  20. Comparative study of analysis methods in biospeckle phenomenon

    NASA Astrophysics Data System (ADS)

    da Silva, Emerson Rodrigo; Muramatsu, Mikiya

    2008-04-01

    In this work we present a review of main statistical properties of speckle patterns and accomplish a comparative study of the more used methods for analysis and extraction of information from optical grainy. The first and second order space-time statistics are dicussed in an overview perspective. The biospeckle phenomenon has detailed attention, specially in its application on monitoring of activity in tissues. The main techniques used to obtain information from speckle patterns are presented, with special prominence to autocorrelation function, co-occurrence matrices, Fujii's method, Briers' contrast and spatial and temporal contrast analisys (LASCA and LASTCA). An incipient method for analysis, based on the study of sucessive correlations contrast, is introduced. Numerical simulations, using diferent probability density functions for velocities of scatterers, were made with two objectives: to test the analysis methods and to give subsidies for interpretation of in vivo results. Vegetable and animal tissues are investigated, achieving the monitoring of senescence process and vascularization maps on leaves, the accompaniment of fungi contamined fruits, the mapping of activity in flowers and the analisys of healing in rats subjected to abdominal surgery. Experiments using the biospeckle phenomenon in microscopy are carried out. At last, it is evaluated the potentiality of biospeckle as diagnosis tool in chronic vein ulcer cared with low intensity laser therapy and the better analysis methods for each kind of tissue are pointed.

  1. Discrete numerical investigation of the ratcheting phenomenon in granular materials

    NASA Astrophysics Data System (ADS)

    Calvetti, Francesco; di Prisco, Claudio

    2010-10-01

    Several relevant geotechnical works, such as railway and road embankments, offshore foundations and vibrating machine foundations, are affected by the progressive accumulation of irreversible settlements. These latter represent the macroscopic evidence of the progressive rearrangement of particles under cycling loading, which is commonly referred to, in the literature, as ratcheting. This phenomenon is well known, but it is quite difficult to describe it by means of an appropriate constitutive model. As a consequence, the evaluation of durability of the aforementioned structures remains an open problem. In this article, the phenomenon will be approached by employing a Distinct Element model capable of describing the evolution of the microstructure induced by cyclic mechanical perturbations. Several analyses are performed in order to stress the influence of both the stress level and loading history on the mechanical response of a numerical model of a sand specimen. The numerical analyses are intended to provide an experimental background for conceiving a simplified macro approach based on generalised plasticity theory. In particular by means of probe test the plastic potential and the hardening parameters will be defined as a function of the current stress state and loading history.

  2. O the Phenomenon of Onset in Magnetoplasmadynamic Thrusters

    NASA Astrophysics Data System (ADS)

    Subramaniam, Vishwanath Vekateswaran

    The performance of Magnetoplasmadynamic (MPD) thrusters has been severely limited by 'onset'. The destructive onset phenomenon refers to the abrupt increase in voltage oscillations accompanied by severe electrode erosion which occurs at a critical value of the cur- rent for a given mass flow rate. This research is aimed at explaining and quantifying onset. The steady, one-dimensional, self-field flow in the MPD thruster is first analyzed for frozen flow, equilibrium flow, and non-equilibrium flow. This quasi one-dimensional theory explains the behaviour of efficiency and predicts a new mechanism for the onset phenomenon. This model predicts that smoothly accelerating supersonic flow can exist only below a critical current level because of increasing back -EMF. This limit is interpreted as onset and correlates with the experimentally observed J('2)/m onset parameter. In order to quantify electrode erosion rates, the electrode- adjacent boundary layer is analyzed using the results of the quasi one-dimensional theory. The free stream boundary conditions for the steady boundary layer flow analysis are obtained from the results of the quasi one-dimensional theory. Since the electrode wall is rela - tively cold compared to the flow, and since relatively fewer collisions are required for the heavier particles to equilibrate, an approximate two temperature boundary layer theory is developed. The two tem- perature compressible non-equilibrium ionization equations are then solved using momentum integral and energy integral methods. Wall shear stress, wall heat flux, temperature, density, and ioniza - tion fraction profiles are then calculated. These results of the two temperature theory may then be used to estimate rates of erosion by evaporation and due to sputtering. The major accomplishments of this thesis include the develop- ment of a new theory that for the first time, predicts onset due to an excessive back-EMF at high currents, the establishment of the importance of

  3. NASA Glenn Research Center Experience with "LENR Phenomenon"

    NASA Technical Reports Server (NTRS)

    Wrbanek, Susan Y.; Fralick, Gustave C.; Wrbanek, John D.; Niedra, Janis M.

    2012-01-01

    Since 1989 NASA Glenn Research Center (GRC) has performed some small-scale limited experiments that show evidence of effects claimed by some to be evidence of Low Energy Nuclear Reactions (LENR). The research at GRC has involved observations and work on measurement techniques for observing the temperature effects in reactions of isotopes of hydrogen with palladium hydrides. The various experiments performed involved loading Pd with gaseous H2 and D2, and exposing Pd thin films to multi-bubble sonoluminescence in regular and deuterated water. An overview of these experiments and their results will be presented.

  4. NASA Glenn Research Center Experience with LENR Phenomenon

    NASA Technical Reports Server (NTRS)

    Wrbanek, Susan Y.; Fralick, Gustave C.; Wrbanek, John D.; Niedra, Janis M.

    2012-01-01

    Since 1989 NASA Glenn Research Center (GRC) has performed some small-scale limited experiments that show evidence of effects claimed by some to be evidence of Low Energy Nuclear Reactions (LENR). The research at GRC has involved observations and work on measurement techniques for observing the temperature effects in reactions of isotopes of hydrogen with palladium hydrides. The various experiments performed involved loading Pd with gaseous H2 and D2, and exposing Pd thin films to multi-bubble sonoluminescence in regular and deuterated water. An overview of these experiments and their results will be presented.

  5. Evolution as a Self-Organized Critical Phenomenon

    NASA Astrophysics Data System (ADS)

    Sneppen, Kim; Bak, Per; Flyvbjerg, Henrik; Jensen, Mogens H.

    1995-05-01

    We present a simple mathematical model of biological macroevolution. The model describes an ecology of adapting, interacting species. The environment of any given species is affected by other evolving species; hence, it is not constant in time. The ecology as a whole evolves to a "self-organized critical" state where periods of stasis alternate with avalanches of causally connected evolutionary changes. This characteristic behavior of natural history, known as "punctuated equilibrium," thus finds a theoretical explanation as a self-organized critical phenomenon. The evolutionary behavior of single species is intermittent. Also, large bursts of apparently simultaneous evolutionary activity require no external cause. Extinctions of all sizes, including mass extinctions, may be a simple consequence of ecosystem dynamics. Our results are compared with data from the fossil record

  6. Genetic aspects of athletic performance: the African runners phenomenon

    PubMed Central

    Vancini, Rodrigo Luiz; Pesquero, João Bosco; Fachina, Rafael Júlio; Andrade, Marília dos Santos; Borin, João Paulo; Montagner, Paulo César; de Lira, Claudio Andre Barbosa

    2014-01-01

    The current dominance of African runners in long-distance running is an intriguing phenomenon that highlights the close relationship between genetics and physical performance. Many factors in the interesting interaction between genotype and phenotype (eg, high cardiorespiratory fitness, higher hemoglobin concentration, good metabolic efficiency, muscle fiber composition, enzyme profile, diet, altitude training, and psychological aspects) have been proposed in the attempt to explain the extraordinary success of these runners. Increasing evidence shows that genetics may be a determining factor in physical and athletic performance. But, could this also be true for African long-distance runners? Based on this question, this brief review proposed the role of genetic factors (mitochondrial deoxyribonucleic acid, the Y chromosome, and the angiotensin-converting enzyme and the alpha-actinin-3 genes) in the amazing athletic performance observed in African runners, especially the Kenyans and Ethiopians, despite their environmental constraints. PMID:24891818

  7. Genetic aspects of athletic performance: the African runners phenomenon.

    PubMed

    Vancini, Rodrigo Luiz; Pesquero, João Bosco; Fachina, Rafael Júlio; Andrade, Marília Dos Santos; Borin, João Paulo; Montagner, Paulo César; de Lira, Claudio Andre Barbosa

    2014-01-01

    The current dominance of African runners in long-distance running is an intriguing phenomenon that highlights the close relationship between genetics and physical performance. Many factors in the interesting interaction between genotype and phenotype (eg, high cardiorespiratory fitness, higher hemoglobin concentration, good metabolic efficiency, muscle fiber composition, enzyme profile, diet, altitude training, and psychological aspects) have been proposed in the attempt to explain the extraordinary success of these runners. Increasing evidence shows that genetics may be a determining factor in physical and athletic performance. But, could this also be true for African long-distance runners? Based on this question, this brief review proposed the role of genetic factors (mitochondrial deoxyribonucleic acid, the Y chromosome, and the angiotensin-converting enzyme and the alpha-actinin-3 genes) in the amazing athletic performance observed in African runners, especially the Kenyans and Ethiopians, despite their environmental constraints. PMID:24891818

  8. Preliminary Numerical and Experimental Analysis of the Spallation Phenomenon

    NASA Technical Reports Server (NTRS)

    Martin, Alexandre; Bailey, Sean C. C.; Panerai, Francesco; Davuluri, Raghava S. C.; Vazsonyi, Alexander R.; Zhang, Huaibao; Lippay, Zachary S.; Mansour, Nagi N.; Inman, Jennifer A.; Bathel, Brett F.; Splinter, Scott C.; Danehy, Paul M.

    2015-01-01

    The spallation phenomenon was studied through numerical analysis using a coupled Lagrangian particle tracking code and a hypersonic aerothermodynamics computational fluid dynamics solver. The results show that carbon emission from spalled particles results in a significant modification of the gas composition of the post shock layer. Preliminary results from a test-campaign at the NASA Langley HYMETS facility are presented. Using an automated image processing of high-speed images, two-dimensional velocity vectors of the spalled particles were calculated. In a 30 second test at 100 W/cm2 of cold-wall heat-flux, more than 1300 particles were detected, with an average velocity of 102 m/s, and most frequent observed velocity of 60 m/s.

  9. [Healing of harmony: music therapy as a historical cultural phenomenon].

    PubMed

    Gantenbein, U L

    1999-05-20

    The interaction of music and psyche constitutes a phenomenon, which is known to man since antiquity, and, for this reason, was ever since used for healing purposes. The pythagoreans developed a system of musical theory that declared consonance to be a musical interval with the frequencies in a ratio of integer numbers. The cosmical music of the spheres, the played instrumental music and the inner music of man, these all they conceived as a unity. Varied in a manyfold way, this great theme was handed down over the centuries to the present day, being a source of inspiration to music and the sciences. Modern musical therapy is, in the last analysis, based on these intuitive findings. PMID:10412284

  10. Raynaud's phenomenon, cytokines and acupuncture: a case report.

    PubMed

    Omole, Folashade S; Lin, James S; Chu, Tehching; Sow, Charles M; Flood, Anthony; Powell, Michael David

    2012-06-01

    A 30-year-old African-American woman diagnosed in 2006 with primary Raynaud's phenomenon (RP) was seen in the clinic in 2010 and the diagnosis confirmed excluding underlying disorders. Acupuncture was administered bilaterally at the LI4 Hegu acupuncture points for 5 min twice weekly for 2 months, which resulted in improvement in pain severity, joint stiffness and the colour of her fingers and toes. The literature reveals that acupuncture is effective in improving pain severity and joint stiffness in RP. The patient's serum proinflammatory cytokines were compared with those from an ongoing study in our institution and the results indicated that acupuncture therapy might be anti-inflammatory. Acupuncture is relatively safe and should be considered as an alternative treatment or non-pharmacological therapy for pain associated with RP. PMID:22516031

  11. Evolution as a self-organized critical phenomenon

    SciTech Connect

    Sneppen, K.; Bak, P. |; Flyvbjerg, H. |; Jensen, M.H.

    1995-05-23

    We present a simple mathematical model of biological macroevolution. The model describes an ecology of adapting, interacting species. The environment of any given species is affected by other evolving species; hence, it is not constant in time. The ecology as a whole evolves to a {open_quotes}self-organized critical{close_quotes} state where periods of stasis alternate with avalanches of casually connected evolutionary changes. This characteristic behavior of natural history, known as {open_quotes}punctuated equilibrium,{close_quotes} thus finds a theoretical explanation as a self-organized critical phenomenon. The evolutionary behavior of single species is intermittent. Also, large bursts of apparently simultaneous evolutionary activity require no external cause. Extinctions of all sizes, including mass extinctions, may be a simple consequence of ecosystem dynamics. Our results are compared with data from the fossil record. 35 refs., 7 figs.

  12. Focusing phenomenon and stability of spiral-flow jet

    NASA Astrophysics Data System (ADS)

    Horii, Kiyoshi; Matsumae, Yuji; Cheng, Xiao M.; Takei, Masahiro; Yasukawa, Eiji

    1991-02-01

    A new nozzle assembly has been developed for an improved focusing of spiral air jet streams. To obtain a focused and highly stable spiral-flow jet, a nozzle is designed with an annular slit connected to a conical cylinder. Pressurized fluid is forced through the sides of the device into the buffer area and then through the annular slit into the pipe entrance. The fluid, passing through the conical cylinder, develops a spiral structure with a steeper axial velocity distribution, caused by Coanda effect and the instability of flow. The jet stream velocity as well as its focusing phenomenon was experimentally determined using a laser sheet method. The results clearly indicate the focusing characteristic and the high stability of spiral flow jet.

  13. [Female genital modification: survey of new phenomenon for nurses today].

    PubMed

    Mitello, Lucia; Proietti, Andrea

    2006-01-01

    The immigration that there was in Italy in the last years has provoked a big cultural and social change for the country. Nurses that belong to social sector cannot escape from that change, and they have got to admit those new reality and develop new assistential and analysis methodologies. The immigrants that arrive in Italy came from more than 150 counties in the world, poor countries of the third world. The object of this research is to find out how nursing profession confronts itself with a new multiculture situation, the way to conciliate the ethical principles of the profession with the different cultures and learning that medical operators of an Italian hospital got about the immigrants: MGF (feminine genital modifications). The research wants to understand this phenomenon that is very diffuse, so the meeting with the differences is a reason to develop and not a imposition of a value on the other value. PMID:17132468

  14. The Superheat Phenomenon in the Combustion of Magnesium Particles

    NASA Technical Reports Server (NTRS)

    Shafirovich, E. IA.; Goldshleger, U. I.

    1992-01-01

    Magnesium is known to be a likely fuel for engines that could work in the CO2 atmospheres of Mars and Venus. The present paper reports temperature measurements of magnesium samples during combustion in CO2. The burning sample temperature increases with the decrease in the initial size. The temperature of the 1-mm samples is 300-400 K higher than the boiling point of magnesium. The stability of the superheated drop is explained by the presence of a porous shell on the surface. An attempt has been made to describe vaporization on the superheated drop by the Knudsen-Langmuir equation. During combustion at high-pressure fragment ejection of the flame is observed in high-speed motion pictures. This phenomenon is shown to be connected with the drop superheat. The repeated fracture of the outer shell formed in the flame ensures the complete burnout of metal particles at high pressure.

  15. The Takete-Maluma phenomenon in autism spectrum disorders.

    PubMed

    Occelli, Valeria; Esposito, Gianluca; Venuti, Paola; Arduino, Giuseppe Maurizio; Zampini, Massimiliano

    2013-01-01

    It has been reported that people tend to preferentially associate phonemes like /m/, /l/, /n/ to curvilinear shapes and phonemes like /t/, /z/, /r/, /k/ to rectilinear shapes. Here we evaluated the performance of children/adolescents with autism spectrum disorders (ASD) and neurotypical controls in this audiovisual congruency phenomenon. Pairs of visual patterns (curvilinear vs rectilinear) were presented to a group of ASD participants (low- or high-functioning) and a group of age-matched neurotypical controls. Participants were asked to associate each item to non-meaningful phoneme clusters. ASD participants showed a lower proportion of expected association responses than the controls. Within the ASD group the performance varied as a function of the severity of the symptomatology. These data suggest that children/adolescents with ASD show, although at different degrees as a function of the severity of the ASD, lower phonetic-iconic congruency response patterns than neurotypical controls, pointing to poorer multisensory integration capabilities. PMID:23700961

  16. Resonance phenomenon of the ATP motor as an ultrasensitive biosensor.

    PubMed

    Wang, Peirong; Zhang, Xiaoguang; Zhang, Xu; Wang, Xia; Li, Xueren; Yue, Jiachang

    2012-09-28

    We designed a rotary biosensor as a damping effector, with the rotation of the F(0)F(1)-ATPase driven by Adenosine Triphosphate (ATP) synthesis being indicated by the fluorescence intensity and a damping effect force being induced by the binding of an RNA molecule to its probe on the rotary biosensor. We found that the damping effect could contribute to the resonance phenomenon and energy transfer process of our rotary biosensor in the liquid phase. This result indicates that the ability of the rotary motor to operate in the vibration harmonic mode depends on the environmental conditions and mechanism in that a few molecules of the rotary biosensor could induce all of the sensor molecules to fluoresce together. These findings contribute to the theory study of the ATPase motor and future development of biosensors for ultrasensitive detection. PMID:22960174

  17. A theory of the high-mode phenomenon for stellarators

    SciTech Connect

    Shaing, K.C.

    1995-09-01

    It is shown that besides the ion orbit loss mechanism, which occurs in a region a {minus} {var_epsilon}{sub t}{rho}{sub p} < r < a, the collisionless drift-orbit transport flux can also drive the poloidal {rvec E} {times} {rvec B} velocity in a region r < a {minus} {var_epsilon}{sub t}{rho}{sub p} in stellarators. Here, r is the minor radius, a is the plasma radius, {var_epsilon}{sub t} is the toroidal amplitude of the magnetic field spectrum, {rvec E} is the electric field, {rvec B} is the magnetic field, and {rho}{sub p} is the poloidal ion gyroradius. The transport-fluxdriven {rvec E} {times} {rvec B} velocity can be triggered most efficiently by an increase of the ion temperature gradient. The theory is applied to the high-mode (H-mode) phenomenon observed in stellarators.

  18. Quantum phase slip phenomenon in ultra-narrow superconducting nanorings

    PubMed Central

    Arutyunov, Konstantin Yu.; Hongisto, Terhi T.; Lehtinen, Janne S.; Leino, Leena I.; Vasiliev, Alexander L.

    2012-01-01

    The smaller the system, typically - the higher is the impact of fluctuations. In narrow superconducting wires sufficiently close to the critical temperature Tc thermal fluctuations are responsible for the experimentally observable finite resistance. Quite recently it became possible to fabricate sub-10 nm superconducting structures, where the finite resistivity was reported within the whole range of experimentally obtainable temperatures. The observation has been associated with quantum fluctuations capable to quench zero resistivity in superconducting nanowires even at temperatures T→0. Here we demonstrate that in tiny superconducting nanorings the same phenomenon is responsible for suppression of another basic attribute of superconductivity - persistent currents - dramatically affecting their magnitude, the period and the shape of the current-phase relation. The effect is of fundamental importance demonstrating the impact of quantum fluctuations on the ground state of a macroscopically coherent system, and should be taken into consideration in various nanoelectronic applications. PMID:22389762

  19. Air Conditioning Stall Phenomenon Testing, Model Development, and Simulation

    SciTech Connect

    Irminger, Philip; Rizy, D Tom; Li, Huijuan; Smith, Travis; Rice, C Keith; Li, Fangxing; Adhikari, Sarina

    2012-01-01

    Electric distribution systems are experiencing power quality issues of extended reduced voltage due to fault-induced delayed voltage recovery (FIDVR). FIDVR occurs in part because modern air conditioner (A/C) and heat pump compressor motors are much more susceptible to stalling during a voltage sag or dip such as a sub-transmission fault. They are more susceptible than older A/C compressor motors due to the low inertia of these newer and more energy efficient motors. There is a concern that these local reduced voltage events on the distribution system will become more frequent and prevalent and will combine over larger areas and challenge transmission system voltage and ultimately power grid reliability. The Distributed Energy Communications and Controls (DECC) Laboratory at Oak Ridge National Laboratory (ORNL) has been employed to (1) test, (2) characterize and (3) model the A/C stall phenomenon.

  20. Trapping - A control phenomenon of spinning drag-free satellites.

    NASA Technical Reports Server (NTRS)

    Powell, J. D.

    1971-01-01

    A drag-free satellite contains a proof mass in an internal cavity and is controlled in translation so that it never touches the proof mass. The satellite shields the proof mass from external forces thus allowing the proof mass to follow a drag-free orbit. Spinning the satellite is desirable because it attenuates the effect of proof mass disturbing forces and simplifies the attitude control. The design of a translation controller for a spinning drag-free satellite typically includes a deadspace to eliminate chatter. This design feature and the inability to locate precisely the mass center give rise to a phenomenon called trapping that potentially could waste significant amounts of propellant. A theory is developed and experimentally verified that explains the role of these factors and provides insight into the effect of other control parameters.

  1. Homicide in five southern states: a firearms phenomenon.

    PubMed

    Ruben, E R; Leeper, J D

    1981-03-01

    Homicide is a leading contributor to loss of life in the productive years. Of the 20,000 homicides yearly in the United States, the majority are committed with firearms. Because homicide rates and gun ownership are highest in the southern states, a descriptive study of 20,980 homicides occurring in five southern states between 1967-1975 was done with particular emphasis on the role of firearms. Total rates in this study were 60% to 85% higher than concurrent national rates. Homicide with firearms accounted for 76.2%, and was the only method of homicide to show a significant increase in rate or a distinctive age distribution. Homicide in the US is a firearms phenomenon. Appropriate and effective regulation of access to firearms is an obvious first step in the prevention of this public health problem. PMID:7221624

  2. Venusian "hot spots": physical phenomenon and its quantification.

    PubMed

    Goncharov, V P; Gryanik, V M; Pavlov, V I

    2002-12-01

    An overall picture of the Venusian hot spots phenomenon is considered in the framework of the simplest conceptual models that admit the solutions in the form of steadily rotating "hot" vortices. Model assumptions take into account only those features of the middle atmosphere in the polar region of Venus that are supported by observational data and are essential for understanding the physical mechanism initiating similar vortices. The problem is analyzed in the framework of both the pointlike and petal-like models of cyclostrophic vortices. Interpretation of these models as an upper and lower bound of a complete theory allows one to find the region of existence of the regimes responsible for the Venusian hot spots and also to establish and assess numerically conditions under which such vortices can be formed. The emphasis is on a comparison of the theoretically established results with the observational data. PMID:12513399

  3. Modeling of Electromagnetic Phenomenon in Fractional Dimensional Space

    NASA Astrophysics Data System (ADS)

    Zubair, Muhammad; Ang, L. K.

    Fractional dimensional space has emerged as an extremely useful concept in many areas of physics, including electromagnetic (EM) theory. The development made in the area of fractional calculus has made it possible to study the most important physical phenomenon in a generalized D-dimensional fractional space. It is worthwhile to mention that many natural objects, such as clouds, snowflakes, rough surfaces, cracks, turbulence in fluids, are aptly described by dimensions of fractional order. Therefore, EM wave propagation in such fractal media is best characterized by considering an effective space of non-integer (fractional) dimensions. Here we present the recent developments in the study of differential Maxwell equations in a D-dimensional fractional space, where D is a non-integer value. Same examples will be used in order to show the transition to the traditional non-fractional conditions or settings.

  4. Contrast-Induced Nephropathy: An "All or None" Phenomenon?

    PubMed

    Katsiki, Niki; Athyros, Vasilios G; Karagiannis, Asterios; Mikhailidis, Dimitri P

    2015-07-01

    Contrast-induced nephropathy (CIN) represents an important adverse effect of contrast media (CM) administration. Contrast-induced nephropathy is associated with prolonged hospitalization as well as increased cardiovascular morbidity, renal morbidity, and all-cause mortality. Several risk factors may predict CIN incidence, and various scores and ratios have been proposed to identify high-risk patients. Novel biomarkers may provide an earlier diagnosis of CIN. A multifactorial approach is required for CIN prevention including hydration, administration of low- or iso-osmolar CM, minimizing CM volume, and statin administration. Renal function may deteriorate after CM administration, even in the absence of CIN. Therefore, this deterioration may not be an "all or none" phenomenon; it may well occur in many patients receiving CM, with/without CIN, and may prove to be an underestimated risk factor. Patients should be followed up for longer periods as outpatients after CM exposure to assess kidney function and predict subsequent increased morbidity and mortality. PMID:25225196

  5. [Molecular bases of cellular senescence: Hayflick phenomenon 50 years later].

    PubMed

    Sosińska, Patrycja; Mikuła-Pietrasik, Justyna; Książek, Krzysztof

    2016-01-01

    Normal human somatic cells have strictly limited proliferative capacity and reach a state of senescence when it becomes exhausted. It is believed that senescence is a response to extensive and irreparable DNA injury, localized in telomeric and/or non-telomeric regions of the genome. Main cause of this damage is oxidative stress, increasing due to deteriorated function of mitochondria. Senescent cells accumulate in tissues during aging, which is causatively linked with the development of various pathologies in elderly individuals, including cancer. This paper, prepared exactly 50 years after Leonard Hayflick's discovery of the relationship between cellular senescence and organismal aging is aimed at presenting the current knowledge about molecular determinants of senescence, with particular emphasis paid to the role of oxidative stress, effectors of senescence at the level of cell cycle, markers of this phenomenon, and the effect of senescent cells on the development of certain age-related diseases. PMID:27117098

  6. Acute transient deafness representing a negative epileptic phenomenon.

    PubMed

    Shahar, Eli; Ravid, Sarit; Genizi, Jacob; Schif, Aharon

    2010-07-01

    We report herein 2 children who presented with acute deafness heralding an epileptic event manifesting thereafter by loss of consciousness and tonic generalized posturing, possibly reflecting a negative epileptic phenomenon. The first previously healthy male had 2 paroxysmal episodes 7 months apart, starting with acute deafness lasting for a few minutes followed by loss of consciousness and generalized tonic posturing for 10 minutes. Electroencephalography (EEG) during the second episodes demonstrated generalized epileptiform discharges. The second with previously controlled partial complex seizures presented with episodes of complete deafness lasting for a few minutes followed by loss of consciousness and focal tonic posturing lasting 10 minutes. Such acute deafness represented an aura of a focal seizure substantiated by right focal temporal epileptic discharges within the region of the primary auditory cortex. Therefore, EEG should be performed in any case of acute transient deafness, even in the absence of accompanying overt clinical seizures. PMID:20042694

  7. A mass phenomenon: the social evolution of obesity.

    PubMed

    Strulik, Holger

    2014-01-01

    This paper proposes a theory for the social evolution of obesity. It considers a society in which individuals experience utility from consumption of food and non-food, the state of their health, and the evaluation of their appearance by others. The theory explains under which conditions poor persons are more prone to be overweight although eating is expensive and it shows how obesity occurs as a social phenomenon such that body mass continues to rise long after the initial cause (e.g. a lower price of food) is gone. The paper investigates the determinants of a steady state at which the median person is overweight and how an originally lean society arrives at such a steady state. Extensions of the theory towards dietary choice and the possibility to exercise in order to lose weight demonstrate robustness of the basic mechanism and provide further interesting results. PMID:24316457

  8. Same-sex marriage: a new social phenomenon.

    PubMed

    Chamie, Joseph; Mirkin, Barry

    2011-01-01

    Same-sex marriage (SSM) is a new social phenomenon. In modern times SSM did not exist until the 21st century when an increasing number of countries began permitting same-sex couples to marry legally. This study presents statistical and related evidence concerning SSM worldwide, with special attention to the United States, where SSM has evolved into a major political and legal issue. In addition to examining data on levels and trends, differentials between men and women are investigated. The study also considers common arguments for and against SSM and likely changes in laws and policies that may occur. Although same-sex marriage now exists in a small number of countries and US states, its consequences and implications are being felt far beyond the borders of those countries and areas. In coming years same-sex marriage will remain a controversial and salient part of the legal, political, and cultural landscape, locally, nationally, and internationally. PMID:22167814

  9. Credit use: psychological perspectives on a multifaceted phenomenon.

    PubMed

    Kamleitner, Bernadette; Hoelzl, Erik; Kirchler, Erich

    2012-01-01

    Consumer borrowing is a highly topical and multifaceted phenomenon as well as a popular subject for study. We focus on consumer credit use and review the existing literature. To categorize what is known we identify four main psychological perspectives on the phenomenon: credit use as (1) a reflection of the situation, (2) a reflection of the person, (3) a cognitive process, and (4) a social process. On top of these perspectives we view credit use as a process that entails three distinct phases: (1) processes before credit acquisition, (2) processes at credit acquisition, and (3) processes after credit acquisition. We review the international literature along a two-tier structure that aligns the psychological perspectives with a process view of credit. This structure allows us to identify systematic concentrations as well as gaps in the existing research. We consolidate what is known within each perspective and identify what seems to be most urgently missing. Some of the most important gaps relate to research studying credit acquisition from the perspective of credit use as a reflection of the person or as a social process. In particular, research on credit use as a reflection of the person appears to focus exclusively on the first stage of the credit process. We conclude with a discussion that reaches across perspectives and identifies overarching gaps, trends, and open questions. We highlight a series of implicit linkages between perspectives and the geographical regions in which studies related to the perspectives were conducted. Beyond diagnosing a geographical imbalance of research, we argue for future research that systematically addresses interrelations between perspectives. We conclude with a set of global implications and research recommendations. PMID:22181814

  10. Automatic arteriovenous crossing phenomenon detection on retinal fundus images

    NASA Astrophysics Data System (ADS)

    Hatanaka, Yuji; Muramatsu, Chisako; Hara, Takeshi; Fujita, Hiroshi

    2011-03-01

    Arteriolosclerosis is one cause of acquired blindness. Retinal fundus image examination is useful for early detection of arteriolosclerosis. In order to diagnose the presence of arteriolosclerosis, the physicians find the silver-wire arteries, the copper-wire arteries and arteriovenous crossing phenomenon on retinal fundus images. The focus of this study was to develop the automated detection method of the arteriovenous crossing phenomenon on the retinal images. The blood vessel regions were detected by using a double ring filter, and the crossing sections of artery and vein were detected by using a ring filter. The center of that ring was an interest point, and that point was determined as a crossing section when there were over four blood vessel segments on that ring. And two blood vessels gone through on the ring were classified into artery and vein by using the pixel values on red and blue component image. Finally, V2-to-V1 ratio was measured for recognition of abnormalities. V1 was the venous diameter far from the blood vessel crossing section, and V2 was the venous diameter near from the blood vessel crossing section. The crossing section with V2-to-V1 ratio over 0.8 was experimentally determined as abnormality. Twenty four images, including 27 abnormalities and 54 normal crossing sections, were used for preliminary evaluation of the proposed method. The proposed method was detected 73% of crossing sections when the 2.8 sections per image were mis-detected. And, 59% of abnormalities were detected by measurement of V1-to-V2 ratio when the 1.7 sections per image were mis-detected.

  11. Suicide tourism: a pilot study on the Swiss phenomenon.

    PubMed

    Gauthier, Saskia; Mausbach, Julian; Reisch, Thomas; Bartsch, Christine

    2015-08-01

    While assisted suicide (AS) is strictly restricted in many countries, it is not clearly regulated by law in Switzerland. This imbalance leads to an influx of people-'suicide tourists'-coming to Switzerland, mainly to the Canton of Zurich, for the sole purpose of committing suicide. Political debate regarding 'suicide tourism' is taking place in many countries. Swiss medicolegal experts are confronted with these cases almost daily, which prompted our scientific investigation of the phenomenon. The present study has three aims: (1) to determine selected details about AS in the study group (age, gender and country of residence of the suicide tourists, the organisation involved, the ingested substance leading to death and any diseases that were the main reason for AS); (2) to find out the countries from which suicide tourists come and to review existing laws in the top three in order to test the hypothesis that suicide tourism leads to the amendment of existing regulations in foreign countries; and (3) to compare our results with those of earlier studies in Zurich. We did a retrospective data analysis of the Zurich Institute of Legal Medicine database on AS of non-Swiss residents in the last 5 years (2008-2012), and internet research for current legislation and political debate in the three foreign countries most concerned. We analysed 611 cases from 31 countries all over the world. Non-terminal conditions such as neurological and rheumatic diseases are increasing among suicide tourists. The unique phenomenon of suicide tourism in Switzerland may indeed result in the amendment or supplementary guidelines to existing regulations in foreign countries. PMID:25142806

  12. Vacuum Phenomenon of the Sacroiliac Joint: Correlation with Sacropelvic Morphology

    PubMed Central

    Higashino, Kosaku; Morimoto, Masatoshi; Sakai, Toshinori; Yamashita, Kazuta; Abe, Mitusnobu; Nagamachi, Akihiro; Sairyo, Koichi

    2016-01-01

    Study Design A radiologic study of sacropelvic morphology and vacuum phenomenon of sacroiliac joint in subjects unrelated to low back pain. Purpose The aim of this study is to describe the relationship between sacropelvic morphology and vacuum phenomenon of the sacroiliac joint. Overview of Literature Lumbopelvic alignment and sacropelvic morphology are associated with the pathomechanisms of various spinal disorders. The vacuum phenomena of the sacroiliac joint (SJVP) are often observed in clinical practice, but the relationships between these phenomena and sacropelvic morphology have not been investigated. This study examined the prevalence of SJVP in computed tomography (CT) images and the relationship between sacropelvic morphology and SJVP. Methods We analyzed multiplanar CT images of 93 subjects (59 men, 34 women). Pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and lumbar lordosis (LL) were measured using the three-dimensional reconstruction method. The prevalence of SJVP in multiplanar CT images were reviewed. Roland-Morris Disability Questionnaire (RDQ) scores and the modified Japanese Orthopedic Association (JOA) score, which focuses on subjective symptoms and restriction of activities of daily living, were also obtained from all the subjects. Results Thirty-six of the 93 subjects had SJVP (39%), with marked female predominance (91% women, 8.5% men). Men with SJVP had significantly lower PI than men without SJVP (35.1° vs. 46.3°, p<0.05). There was no correlation between SJVP and the modified JOA or RDQ scores. Conclusions These data suggest that differences in sacropelvic morphology can influence the biomechanical environment and contribute to SJVP in men. Presence of SJVP did not affect JOA or RDQ scores. PMID:27559459

  13. Dynamic topography of visual evoked potentials and extrageniculate projection in case of Riddoch phenomenon.

    PubMed

    Tsutsui, J; Ichihashi, K; Kimura, H

    1984-01-01

    A 34-year-old woman showing the Riddoch phenomenon was studied by the technique of dynamic topography of visual evoked potential (VEP). This case had cortical blindness which developed during the process of massive intestinal hemorrhage, shock and surgery. The visual acuity was limited to hand movement, and perception of white and colored light was present, but there was no form recognition. Tracking eye movement for a flashlight was possible and optokinetic nystagmus (OKN) also appeared. CT-scan showed a diffuse low density area in the white matter of the occipital lobe. The VEPs by flash and a checkerboard of 60'-100' were detectable. Dynamic topography of the VEP showed that a strong negative deflection from the brainstem appeared at around 30 msec and this deflection expanded to the parietal region at about 90 msec. Subsequently, a positive deflection extending from the frontal region to the occipital region continued at 100 msec to 150 msec. Such a process of reaction is not observed in the normal subject. These findings suggest that the visual reaction was conducted abnormally through the extrageniculate system; from the brainstem to the parietal area and then to the occipital area. PMID:6748358

  14. Drug Reactions

    MedlinePlus

    ... using any of these products. Some types of food may also cause adverse drug reactions. For example, grapefruit and grapefruit juice, as well as alcohol and caffeine, may affect how drugs work. Every time your doctor ... interactions with any foods or beverages. What about medicines I've used ...

  15. Regioselective Mitsunobu Reaction of Partially Protected Uridine.

    PubMed

    Szlenkier, Maurycy; Kamel, Karol; Boryski, Jerzy

    2016-08-01

    Mitsunobu reaction of partially acylated uridine proceeds with high regioselectivity for intramolecular SN2 anhydro linkage closuring. Under the reaction conditions, an isomeric mixture of diacyl uridine derivatives with either free 2'- or 3'-hydroxyl group was transformed into a single cyclonucleosidic product, 2,2'-anhydro-3',5'-di-O-acyluridine. This paper presents a possible mechanism of the reactions, the explanation of observed phenomenon based on semiempirical and density functional theory (DFT) calculations and possible utility of this synthetic pathway. PMID:27351239

  16. Aquatic Organic Matter Fluorescence - from phenomenon to application

    NASA Astrophysics Data System (ADS)

    Reynolds, Darren

    2014-05-01

    The use of fluorescence to quantify and characterise aquatic organic matter in river, ocean, ground water and drinking and waste waters has come along way since its discovery as a phenomenon in the early 20th century. For example, there are over 100 papers published each year in international peer reviewed journals, an order of magnitude increase since a decade ago (see Figure taken from ISI database from 1989 to 2007 for publications in the fields of river water and waste water). Since then it has been extensively used as a research tool since the 1990's by scientists and is currently used for a wide variety of applications within a number of sectors. Universities, organisations and companies that research into aquatic organic matter have either recently readily use appropriate fluorescence based techniques and instrumentation. In industry and government, the technology is being taken up by environmental regulators and water and wastewater companies. This keynote presentation will give an overview of aquatic organic matter fluorescence from its conception as a phenomenon through to its current use in a variety of emerging applications within the sectors concerned with understanding, managing and monitoring the aquatic environment. About the Speaker Darren Reynolds pioneered the use of fluorescence spectroscopy for the analysis of wastewaters in the 1990's. He currently leads a research group within the Centre for Research in Biosciences and sits on the Scientific Advisory Board for the Institute of Bio-Sensing Technology at the University of the West of England, Bristol. He is a multidisciplinary scientist concerned with the development of technology platforms for applications in the fields of environment/agri-food and health. His current research interests include the development of optical technologies and techniques for environmental and biological sensing and bio-prospecting applications. He is currently involved in the development and use of synthetic biology

  17. Accordion phenomenon of the hepatic artery: mimicker of vasospasm or intimal injury

    PubMed Central

    Koyama, Yoshinori; Tsushima, Yoshito

    2016-01-01

    The accordion phenomenon occurs because of mechanical distortion of a straightened vessel during coronary and vascular interventions. To date, however, this phenomenon has not been reported in vessels of the upper abdomen. We therefore describe the accordion phenomenon of the hepatic artery during transarterial chemoembolization seen while treating a liver tumor. As the accordion phenomenon is now known to involve hepatic arteries, it should be differentiated from vascular complications such as vasospasm or intimal injury. PMID:27570635

  18. Phenomenon of life: between equilibrium and non-linearity.

    PubMed

    Galimov, E M

    2004-12-01

    A model of ordering applicable to biological evolution is presented. It is shown that a steady state (more precisely approaching to a steady state) system of irreversible processes, under conditions of disproportionation of entropy, produces a lower-entropy product, that is, ordering. The ordering is defined as restricting of degrees of freedom: freedom of motion, interactions etc. The model differs from previous ones in that it relates the ordering to processes running not far from equilibrium, described in the linear field of non-equilibrium thermodynamics. It is shown that a system, which includes adenosine triphosphate (ATP) to adenosine diphosphate (ADP) conversion meets the demands of the physical model: it provides energy maintaining steady state conditions, and hydrolysis of ATP proceeding with consumption of water can be tightly conjugated with the most important reactions of synthesis of organic polymers (peptides, nucleotide chains etc.), which proceed with release of water. For these and other reasons ATP seems to be a key molecule of prebiotic evolution. It is argued that the elementary chemical reaction proceeding under control of an enzyme is not necessarily far from equilibrium. The experimental evidence supporting this idea, is presented. It is based on isotope data. Carbon isotope distribution in biochemical systems reveals regularity, which is inherent to steady state systems of chemical reactions, proceeding not far from equilibrium. In living organisms this feature appears at the statistical level, as many completely irreversible and non-linear processes occur in organisms. However not-far-from-equilibrium reactions are inherent to biochemical systems as a matter of principle. They are reconcilable with biochemical behavior. Extant organisms are highly evolved entities which, however, show in their basis the same features, as the simplest chemical systems must have had been involved in the origin of life. Some consequences following from the

  19. Open Dialogue Approach - about the phenomenon of Scandinavian Psychiatry.

    PubMed

    Kłapciński, Michał M; Rymaszewska, Joanna

    2015-01-01

    After twenty years of transformation of Finnish mental health care, in the late 80s and early 90s of the last century, incidence of schizophrenia in Western Lapland dropped from 35/100,000 to 7/100,000. This phenomenon is linked with Yrjo O. Alanen et al. who investigated schizophrenia treatment outcomes and psychosocial rehabilitation of people with schizophrenia. Investigators focused on an individually tailored psychotherapeutic recovery plan during patient's hospitalization, including care for patients' families. Within the "Finnish National Schizophrenia Project" the principles of the Need-Adapted Treatment were created and 50% of Finland's country gained access to mobile crisis intervention teams. Further studies were continued within "Acute PsychosisIntegrated Treatment Project" (1992-1993) which locally, in Western Lapland, proceeded into "Open Dialogue in Acute Psychosis Project" (ODAP) (1994-1997). In this approach, all important decisions regarding the patient, including hospitalization or pharmacotherapy, are discussed not only with the entire therapeutic team, but also with the patient and his family members. Two - and five-year follow-ups demonstrated high treatment efficacy as well as important cost reduction in mental health care spending. First two"Open Dialogue Method" training courses for representatives of the medical, psychological, nursing and social care have been completed in Poland in October 2014. Studies evaluating the therapeutic effectiveness of the described approach are being planned. PMID:26909395

  20. [Some Italian research on the phenomenon of filicide].

    PubMed

    Mastronardi, Vincenzo; De Vita, Luana; Umani Ronchi, Federica

    2012-01-01

    In this work on the phenomenon of filicide, structured on the basis of the examination of hundreds of cases from 1880 to 2010, the five causes were taken into account: the altruistic filicide, the high psychotic component, that of the unwanted child, accidental filicide, and the spouse revenge filicide. Following the observation of Resnick's (1969) 530 psycho-biographiesss, a more structured typing was developed which on the basis of their motive and/or psychopathology divides mother infanticide into 20 categories: the first 10 imply full imputability, stessor events, for piety, immaturity of the mother, hyperactivity of the child, the son of the blame, Medea syndrome, disturbance dependent, narcissistic, or histrionic personality, unwanted child, depression, behavioral disorders involved in the recruitment of drugs. The remaining 10 are those where there may be impairment of traceability for postpartum psychosis (Brief psychotic disorder), Fundus hysterical plus precipitating factors, major depression, schizophrenia, twilight state, psychotic disorder due to a general medical condition, epilepsy, oligophrenia, multiple sclerosis and multiple personality, which however appears to be quite rare. An examination of the causes of death concludes the work. PMID:23023118

  1. When does single-mode lasing become a condensation phenomenon?

    PubMed

    Fischer, Baruch; Weill, Rafi

    2012-11-19

    We present a generic route to classical light condensation (LC) in linear photonic mode systems, such as cw lasers, with different grounds from regular Bose-Einstein condensation (BEC). LC is based on weighting the modes in a noisy environment (spontaneous emission, etc.) in a loss-gain scale, rather than in photon energy. It is characterized by a sharp transition from a multi- to single-mode oscillation. The study uses a linear multivariate Langevin formulation which gives a mode occupation hierarchy that functions like Bose-Einstein statistics. Condensation occurs when the spectral filtering has near the lowest-loss mode a power law dependence with exponent smaller than 1. We then discuss how condensation can occur in photon systems, its relation to lasing and the difficulties to observe regular photon-BEC in laser cavities. We raise the possibility that experiments on photon condensation in optical cavities fall in a classical LC or lasing category rather than being a thermal-quantum BEC phenomenon. PMID:23187523

  2. Retinoid signaling in inner ear development: A "Goldilocks" phenomenon.

    PubMed

    Frenz, Dorothy A; Liu, Wei; Cvekl, Ales; Xie, Qing; Wassef, Lesley; Quadro, Loredana; Niederreither, Karen; Maconochie, Mark; Shanske, Alan

    2010-12-01

    Retinoic acid (RA) is a biologically active derivative of vitamin A that is indispensable for inner ear development. The normal function of RA is achieved only at optimal homeostatic concentrations, with an excess or deficiency in RA leading to inner ear dysmorphogenesis. We present an overview of the role of RA in the developing mammalian inner ear, discussing both how and when RA may act to critically control a program of inner ear development. Molecular mechanisms of otic teratogenicity involving two members of the fibroblast growth factor family, FGF3 and FGF10, and their downstream targets, Dlx5 and Dlx6, are examined under conditions of both RA excess and deficiency. We term the effect of too little or too much RA on FGF/Dlx signaling a Goldilocks phenomenon. We demonstrate that in each case (RA excess, RA deficiency), RA can directly affect FGF3/FGF10 signaling within the otic epithelium, leading to downregulated expression of these essential signaling molecules, which in turn, leads to diminution in Dlx5/Dlx6 expression. Non-cell autonomous affects of the otic epithelium subsequently occur, altering transforming growth factor-beta (TGFβ) expression in the neighboring periotic mesenchyme and serving as a putative explanation for RA-mediated otic capsule defects. We conclude that RA coordinates inner ear morphogenesis by controlling an FGF/Dlx signaling cascade, whose perturbation by deviations in local retinoid concentrations can lead to inner ear dysmorphogenesis. PMID:21108385

  3. Cyberbullying: a 21st Century Health Care Phenomenon.

    PubMed

    Carter, Jemica M; Wilson, Feleta L

    2015-01-01

    This study examined bullying and cyberbullying prevalence among 367 adolescents 10 to 18 years of age who were attending schools and community organizations in suburban and urban neighborhoods in the Midwest United States. The correlational design investigated adolescents' daily use of technology that could be used to cyberbully peers, such as cell phones, computers, email, and the Internet. Results showed that 30% of participants had been bullied during school, and 17% had been cyberbullied, with online social networking sites the most common media employed (68%). The majority of participants owned or had access to computers (92%), email accounts (88%), social networking accounts (e.g., Facebook or MySpace) (82%), and cell phones (79%). Daily technology use included an average of two hours on a computer and a median of 71 text messages per day. Logistic regression analysis revealed no significant differences in bullying or cyberbullying prevalence based on location (urban or suburban) or demographic characteristics. Given the substantial presence of cyberbullying and the increase in technology use among adolescents in the 21st century, nurses need knowledge of the phenomenon to plan assessments in clinical practice. Early identification and assessment of cyberbullying victims and perpetrators, and development and implementation of effective interventions are needed to reduce this form of bullying among adolescents. PMID:26201169

  4. Investigation of Switching Phenomenon in Metal-Tantalum Oxide Interface.

    PubMed

    Yawar, Abbas; Park, Mi Ra; Hu, Quanli; Song, Woo Jin; Yoon, Tae-Sik; Choi, Young Jin; Kang, Chi Jung

    2015-10-01

    To investigate the nature of the switching phenomenon at the metal-tantalum oxide interface, we fabricated a memory device in which a tantalum oxide amorphous layer acted as a switching medium. Different metals were deposited on top of the tantalum oxide layer to ensure that they will react with some of the oxygen contents already present in the amorphous layer of the tantalum oxide. This will cause the formation of metal oxide (MOx) at the interface. Two devices with Ti and Cu as the top electrodes were fabricated for this purpose. Both devices showed bipolar switching characteristics. The SET and RESET voltages for the Ti top electrode device were ~+1.7 V and ~-2 V, respectively, whereas the SET and RESET voltages for the Cu top electrode device were ~+0.9 V and ~-0.9 V, respectively. In the high-resistance state (HRS) conduction, the mechanisms involved in the devices with Ti and Cu top electrodes were space-charge limited conduction (SCLC) and ohmic, respectively. On the other hand, in the low-resistance state (LRS), the Ti top electrode device undergoes SCLC at a high voltage and ohmic conduction at a low voltage, and the Cu top electrode again undergoes ohmic conduction. From the consecutive sweep cycles, it was observed that the SET voltage gradually decreased with the sweeps for the Cu top electrode device, whereas for the Ti top electrode device, the set voltage did not vary with the sweeps. PMID:26726372

  5. Transit of Venus Culture: A Celestial Phenomenon Intrigues the Public

    NASA Astrophysics Data System (ADS)

    Bueter, Chuck

    2012-01-01

    When Jeremiah Horrocks first observed it in 1639, the transit of Venus was a desirable telescopic target because of its scientific value. By the next transit of Venus in 1761, though, the enlightened public also embraced it as a popular celestial phenomenon. Its stature elevated over the centuries, the transit of Venus has been featured in music, poetry, stamps, plays, books, and art. The June 2004 transit emerged as a surprising global sensation, as suggested by the search queries it generated. Google's Zeitgeist deemed Venus Transit to be the #1 Most Popular Event in the world for that month. New priorities, technologies, and media have brought new audiences to the rare alignment. As the 2012 transit of Venus approaches, the trend continues with publicly accessible capabilities that did not exist only eight years prior. For example, sites from which historic observations have been made are plotted and readily available on Google Earth. A transit of Venus phone app in development will, if fully funded, facilitate a global effort to recreate historic expeditions by allowing smartphone users to submit their observed transit timings to a database for quantifying the Astronomical Unit. While maintaining relevance in modern scientific applications, the transit of Venus has emerged as a cultural attraction that briefly intrigues the mainstream public and inspires their active participation in the spectacle.

  6. V838 Monocerotis revisited: Space phenomenon imitates art

    NASA Astrophysics Data System (ADS)

    2004-03-01

    V838 Monocerotis revisited: Space phenomenon imitates art hi-res Size hi-res: 558 Kb Credits: NASA, the Hubble Heritage Team (AURA/STScI) and ESA V838 Monocerotis revisited: Space phenomenon imitates art "Starry Night", Vincent van Gogh's famous painting, is renowned for its bold whorls of light sweeping across a raging night sky. Although this image of the heavens came only from the artist's restless imagination, a new picture from the NASA/ESA Hubble Space Telescope bears remarkable similarities to the van Gogh work, complete with never-before-seen spirals of dust swirling across trillions of kilometres of interstellar space. This image, obtained with the Advanced Camera for Surveys on February 8, 2004, is Hubble's latest view of an expanding halo of light around a distant star, named V838 Monocerotis (V838 Mon). The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a flashbulb-like pulse of light two years ago. V838 Mon is located about 20,000 light-years away from Earth in the direction of the constellation Monoceros, placing the star at the outer edge of our Milky Way galaxy V838 Monocerotis revisited: Space phenomenon imitates art hi-res Size hi-res: 1989 kb Credits: NASA, the Hubble Heritage Team (AURA/STScI) and ESA V838 Monocerotis revisited: Space phenomenon imitates art "Starry Night", Vincent van Gogh's famous painting, is renowned for its bold whorls of light sweeping across a raging night sky. Although this image of the heavens came only from the artist's restless imagination, a new picture from the NASA/ESA Hubble Space Telescope bears remarkable similarities to the van Gogh work, complete with never-before-seen spirals of dust swirling across trillions of kilometres of interstellar space. This image, obtained with the Advanced Camera for Surveys on February 8, 2004, is Hubble's latest view of an expanding halo of light around a distant star, named V838 Monocerotis (V838 Mon). The

  7. Blocked D phenomenon and relevance of maternal serologic testing.

    PubMed

    Jain, Ashish; Kumawat, Vijay; Marwaha, Neelam

    2015-01-01

    A blood requisition for double-volume exchange transfusion was received for a 2-day-old male child born to a 29-year-old multiparous female (P2002) referred to our institute having neonatal jaundice with encephalopathy; no maternal sample was received. the neonatal blood sample was typed as group A, D-, and the direct antiglobulin test (DAT) was strongly positive (4+) using the gel method. Mono-specific DAT showed the presence of IgG antibodies on neonatal red blood cells (RBCs). Acid elution and gentle heat elution (at 56°C) confirmed the presence of anti-D on neonatal RBCs. The baby received two exchange transfusions with group O, D-, packed RBCs compatible with his own serum. Later, on day 3, the neonate's mother was typed as group AB, D-, and her serum revealed the presence of alloanti-D, -C, and -S reactive in the anti-human globulin phase. The anti-D titer was 1024. this report highlights the "blocking" phenomenon caused by maternal anti-D in a case of hemolytic disease of fetus and newborn with a positive DAT. PMID:26829177

  8. Proof phenomenon as a function of the phenomenology of proving.

    PubMed

    Hipólito, Inês

    2015-12-01

    Kurt Gödel wrote (1964, p. 272), after he had read Husserl, that the notion of objectivity raises a question: "the question of the objective existence of the objects of mathematical intuition (which, incidentally, is an exact replica of the question of the objective existence of the outer world)". This "exact replica" brings to mind the close analogy Husserl saw between our intuition of essences in Wesensschau and of physical objects in perception. What is it like to experience a mathematical proving process? What is the ontological status of a mathematical proof? Can computer assisted provers output a proof? Taking a naturalized world account, I will assess the relationship between mathematics, the physical world and consciousness by introducing a significant conceptual distinction between proving and proof. I will propose that proving is a phenomenological conscious experience. This experience involves a combination of what Kurt Gödel called intuition, and what Husserl called intentionality. In contrast, proof is a function of that process - the mathematical phenomenon - that objectively self-presents a property in the world, and that results from a spatiotemporal unity being subject to the exact laws of nature. In this essay, I apply phenomenology to mathematical proving as a performance of consciousness, that is, a lived experience expressed and formalized in language, in which there is the possibility of formulating intersubjectively shareable meanings. PMID:26160643

  9. [Examination of the escape phenomenon in disease modifying antirheumatic drugs].

    PubMed

    Kawasaki, Yoichi; Moriyama, Masahiro; Shibata, Kazuhiko; Gomita, Yutaka

    2005-03-01

    Although disease-modifying antirheumatic drugs (DMARDs) are used in the treatment of rheumatoid arthritis (RA), the selection of agents in the case of relapse (escape phenomenon) lacks clear-cut standards. Therefore we investigated the rate and conditions of escape as well as the agents used after escapes had occurred. Outpatients of the Matsubara Mayflower Hospital with a history of DMARD administration during the 4 years prior to May 2003 were studied. Those receiving salazosulfapyridine (SASP) had a high escape rate and those receiving methotrexate (MTX) and bucillamine (BC) had a low rate. The continuous duration of administration was long for MTX and BC, but short for sodium aurothiomalate (GST). BC and Actarit (AR) gradually elevated C-reactive protein (CRP) levels and the erythrocyte sedimentation rate (ESR). In patients receiving SASP and MTX, a high level of CRP and high ESR was seen 2 months prior to the occurrence of escape and remained unchanged after escape. With respect to the agents used after escape, SASP and BC were substituted with other DMARDs. A combination with other DMARDs was usually administered to patients who had been receiving MTX. Taken together, the present results clarified the characteristics of DMARD escape and will contribute to the appropriate pharmacotherapy for RA. PMID:15738628

  10. A simple pharmacokinetics subroutine for modeling double peak phenomenon.

    PubMed

    Mirfazaelian, Ahmad; Mahmoudian, Massoud

    2006-04-01

    Double peak absorption has been described with several orally administered drugs. Numerous reasons have been implicated in causing the double peak. DRUG-KNT--a pharmacokinetic software developed previously for fitting one and two compartment kinetics using the iterative curve stripping method--was modified and a revised subroutine was incorporated to solve double-peak models. This subroutine considers the double peak as two hypothetical doses administered with a time gap. The fitting capability of the presented model was verified using four sets of data showing double peak profiles extracted from the literature (piroxicam, ranitidine, phenazopyridine and talinolol). Visual inspection and statistical diagnostics showed that the present algorithm provided adequate curve fit disregarding the mechanism involved in the emergence of the secondary peaks. Statistical diagnostic parameters (RSS, AIC and R2) generally showed good fitness in the plasma profile prediction by this model. It was concluded that the algorithm presented herein provides adequate predicted curves in cases of the double peak phenomenon. PMID:16400712