WorldWideScience

Sample records for psychic blue dot

  1. A roadmap towards habitable exoplanets by the Blue Dots Initiative

    Science.gov (United States)

    Coudé du Foresto, V.

    2011-11-01

    This paper is an abridged version of the report produced by the Blue Dots initiative, whose activities include the elaboration of a roadmap towards the spectroscopic characterization of habitable exoplanets. The full version of the Blue Dots report can be downloaded at http://www.blue-dots.net/spip.php?article105. While the roadmap will need to be updated regularly, it is expected that the methodology developed within Blue Dots will provide a durable framework for the elaboration of future revisions.

  2. Hubble's View of Little Blue Dots

    Science.gov (United States)

    Kohler, Susanna

    2018-02-01

    The recent discovery of a new type of tiny, star-forming galaxy is the latest in a zoo of detections shedding light on our early universe. What can we learn from the unique little blue dots found in archival Hubble data?Peas, Berries, and DotsGreen pea galaxies identified by citizen scientists with Galaxy Zoo. [Richard Nowell Carolin Cardamone]As telescope capabilities improve and we develop increasingly deeper large-scale surveys of our universe, we continue to learn more about small, faraway galaxies. In recent years, increasing sensitivity first enabled the detection of green peas luminous, compact, low-mass (10 billion solar masses; compare this to the Milky Ways 1 trillion solar masses!) galaxies with high rates of star formation.Not long thereafter, we discovered galaxies that form stars similarly rapidly, but are even smaller only 330 million solar masses, spanning less than 3,000 light-years in size. These tiny powerhouses were termed blueberries for their distinctive color.Now, scientists Debra and Bruce Elmegreen (of Vassar College and IBM Research Division, respectively) report the discovery of galaxies that have even higher star formation rates and even lower masses: little blue dots.Exploring Tiny Star FactoriesThe Elmegreens discovered these unique galaxies by exploring archival Hubble data. The Hubble Frontier Fields data consist of deep images of six distant galaxy clusters and the parallel fields next to them. It was in the archival data for two Frontier Field Parallels, those for clusters Abell 2744 and MAS J0416.1-2403, that the authors noticed several galaxies that stand out as tiny, bright, blue objects that are nearly point sources.Top: a few examples of the little blue dots recently identified in two Hubble Frontier Field Parallels. Bottom: stacked images for three different groups of little blue dots. [Elmegreen Elmegreen 2017]The authors performed a search through the two Frontier Field Parallels, discovering a total of 55 little blue dots

  3. Quantum dot blueing and blinking enables fluorescence nanoscopy.

    Science.gov (United States)

    Hoyer, Patrick; Staudt, Thorsten; Engelhardt, Johann; Hell, Stefan W

    2011-01-12

    We demonstrate superresolution fluorescence imaging of cells using bioconjugated CdSe/ZnS quantum dot markers. Fluorescence blueing of quantum dot cores facilitates separation of blinking markers residing closer than the diffraction barrier. The high number of successively emitted photons enables ground state depletion microscopy followed by individual marker return with a resolving power of the size of a single dot (∼12 nm). Nanoscale imaging is feasible with a simple webcam.

  4. Dot gain compensation in the blue noise mask

    Science.gov (United States)

    Yao, Meng; Parker, Kevin J.

    1995-04-01

    Frequency modulated (FM) halftoning or 'stochastic screening,' has attracted a great deal of attention in the printing industry in recent years. It has several advantages over conventional halftoning. But one serious problem that arises in FM halftoning is dot gain. One approach to stochastic screening uses a specially constructed halftone screen, the blue noise mask (BNM), to produce an unstructured and visually appealing pattern of halftone dots at any gray level. In this paper, we will present methods to correct dot gain with the BNM. Dot gain is related to the area-to-perimeter ration of printed spots. We can exploit this feature in different ways. At a medium level, a B>NM pattern will have 'connected' as well as 'isolated' dots. Normally, as we build down BNM patterns to lower levels, a specific number of white dots will be replace by black dots. Since connected white dots are more likely to be picked than isolated white dots, this will results in substantial dot gain because of the increasing number of isolated white dots. We show that it is possible to constrain the process of constructing a BNM such that isolated dots are preferentially removes, thus significantly reducing dot gain in a BNM.

  5. Using the Psychic Blue Dot to Teach about Science (and Pseudoscience)

    Science.gov (United States)

    Ashton, William A.

    2008-01-01

    A new teaching method is described for teaching research methods in an Introductory Psychology curriculum with the goals of making the section on research methods more interesting, providing an active learning environment for research methods and to allow students to examine scientifically the claims of pseudoscience. Student groups created and…

  6. [Psychic disorders].

    Science.gov (United States)

    Pollak, P

    2002-12-01

    Parkinson's disease is a neuropsychiatric disease with multiple psychic disorders. They mainly result from a combination between neuropathological lesions and antiparkinsonian drugs. The most frequent psychic disorders are depression and psychosis. So far, pharmacological treatments of depression has been poorly evaluated. It is suggested that the first-line treatment of depression in Parkinson's disease is the class of the Selective Serotonin Reuptake Inhibitors. The occurrence of worsening in parkinsonism and agitation in rare cases necessitates a meticulous clinical follow-up. The treatment of psychosis is based on the reduction of antiparkinsonian medications, by tapering and stopping, if necessary, the drugs with the highest risk-to-benefit ratio first. When psychosis persists despite a simple levodopa monotherapy, then an antipsychotic drug is added. Clozapine is the only officially approved drug for psychosis in Parkinson's disease. Two double blind studies showed a clear antipsychotic effect without worsening of parkinsonism. Quetiapine, another atypical neuroleptic drug without risk of blood dyscrasia may prove to be as effective than clozapine. Olanzapine and risperidone can aggravate parkinsonism and should be used only as a last resort. Future studies will precise the place of anticholinesterases in the treatment of psychosis associated with dementia.

  7. Nonmechanical Infrared Beam Steering Using Blue Addressed Quantum Dot Doped Liquid Crystal Grating

    Science.gov (United States)

    Wang, Xiangru; Huang, Xiaoping; Huang, Ziqiang; Wu, Liang; Shang, Jiyang; Qiu, Qi; Wu, Shuanghong

    2017-01-01

    We present a scheme of nonmechanical laser beam steering using ZnS/InP quantum dots doping nematic liquid crystal as the optical recording film. Because of its internal electric field generated by blue laser-induced charge carrier distribution, liquid crystal molecules are reoriented to form a phase grating which make the incident angle steer to the angle as we desire. Being a nonmechanical programmable laser beam steering, the anisotropy of the relative permittivity tensor and blue laser-induced electric carriers play a significant effect in determining the reorientable liquid crystal molecule and reconfigurable phase modulation of the gratings, that determines the steering angle and steering efficiency.

  8. Synthesis and characterization of small size fluorescent LEEH caped blue emission ZnTe quantum dots

    Directory of Open Access Journals (Sweden)

    Patnaik Sumanta Kumar

    2017-04-01

    Full Text Available We report here for the first time the synthesis of LEEH caped very small size (2 nm ZnTe quantum dots at low temperature (less than 100 °C using a simple chemical route. The effects of aging and stirring time on the absorption spectra of the quantum dots were investigated. The synthesized nanocrystal (NC was characterized by PL, TEM, XRD and the formation of very small size quantum dots having FCC structure was confirmed. Further, blue emission from the prepared sample was observed during exposure to monochromatic UV radiation. ZnTe NCs obtained in this study were found to be more stable compared to those presented in literature reports. ZnTe NCs may be considered as a new material in place of CdTe for optoelectronics devices.

  9. Synthesis, Photoluminescence and Bio-Targeting Applications of Blue Graphene Quantum Dots.

    Science.gov (United States)

    Wang, Jigang; Zhou, Ji; Zhou, Wenhua; Shi, Jilong; Ma, Lun; Chen, Wei; Wang, Yongsheng; He, Dawei; Fu, Ming; Zhang, Yongna

    2016-04-01

    Chemical derived graphene oxide, an atomically thin sheet of graphite with two-dimensional construction, offers interesting physical, electronic, thermal, chemical, and mechanical properties that are currently being explored for advanced physics electronics, membranes, and composites. Herein, we study graphene quantum dots (GQD) with the blue photoluminescence under various parameters. The GQD samples were prepared at different temperatures, and the blue photoluminescence intensity of the solution improved radically as the heating temperatures increased. Concerning PL peak and intensity of the quantum dots, the results demonstrated dependence on time under heating, temperature of heating, and pH adjusted by the addition of sodium hydroxide. After hydrothermal synthesis routes, the functional groups of graphene oxide were altered the morphology showed the stacking configuration, and self-assembled structure of the graphene sheets with obvious wrinkles appeared at the edge structures. In addition, absorption, PL, and PLE spectra of the graphene quantum dots increase with different quantities of sodium hydroxide added. Finally, using GQD to target PNTIA cells was carried out successfully. High uptake efficiency and no cytotoxic effects indicate graphene quantum dots can be suitable for bio-targeting.

  10. Blue Quantum Dot Light-Emitting Diodes with High Electroluminescent Efficiency.

    Science.gov (United States)

    Wang, Lishuang; Lin, Jie; Hu, Yongsheng; Guo, Xiaoyang; Lv, Ying; Tang, Zhaobing; Zhao, Jialong; Fan, Yi; Zhang, Nan; Wang, Yunjun; Liu, Xingyuan

    2017-11-08

    High-efficiency blue CdSe/ZnS quantum dots (QDs) have been synthesized for display application with emission peak over 460 nm with the purpose of reducing the harmful effect of short-wavelength light to human eyes. To reach a better charge balance, different size ZnO nanoparticles (NPs) were synthesized and electrical properties of ZnO NPs were analyzed. Quantum dot light-emitting diodes (QLEDs) based on as-prepared blue QDs and optimized ZnO NPs have been successfully fabricated. Using small-size ZnO NPs, we have obtained a maximum current efficiency (CE) of 14.1 cd A(-1) and a maximum external quantum efficiency (EQE) of 19.8% for QLEDs with an electroluminescence (EL) peak at 468 nm. To the best of our knowledge, this EQE is the highest value in comparison to the previous reports. The CIE 1931 color coordinates (0.136, 0.078) of this device are quite close to the standard (0.14, 0.08) of National Television System Committee (NTSC) 1953. The color saturation blue QLEDs show great promise for use in next-generation full-color displays.

  11. Facile synthesis of blue-emitting carbon dots@mesoporous silica composite spheres

    Science.gov (United States)

    Guo, Ziying; Zhu, Zhenpeng; Zhang, Xinguo; Chen, Yibo

    2018-02-01

    This paper reported a facile and effective approach towards high-efficient composite luminophores by embedding blue-emitting N-doped carbon dots into spherical SiO2 matrix (CDs@SiO2). Mesoporous silica microspheres (r-CDs@MSN) with strong luminescence were synthesized by removing CTAB templates in CDs@SiO2 using reflux with acetone. The r-CDs@MSN possess a spherical morphology with smooth surface and a diameter of 130 nm, while it exhibits an excitation-independent blue emission peak at 440 nm with an internal quantum yield of 21.5%. BET result shows that the corresponding surface area and adsorption total pore volume are 156.27 m2/g and 0.682 cm3/g, which is suitable for the drugs loading and release. The results indicate that r-CDs@MSN might act as a potential fluorescent drug carrier.

  12. Graphene quantum dot synthesis using nanosecond laser pulses and its comparison to Methylene Blue

    Science.gov (United States)

    Kholikov, Khomidkhodza; Thomas, Zachary; Seyitliyev, Dovletgeldi; Smith, Skylar

    A biocompatible photodynamic therapy agent that generates a high amount of singlet oxygen with high water dispersibility and excellent photostability is desirable. In this work, a graphene based biomaterial which is a promising alternative to a standard photosensitizers was produced. Methylene blue was used as a reference photosensitizer. Bacteria deactivation by methylene blue was shown to be inhibited inside human blood due to protein binding. Graphene quantum dots (GQD) were synthesized by irradiating benzene and nickel oxide mixture using nanosecond laser pulses. High resolution transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, and nuclear magnetic resonance (NMR) were used for characterization of GQDs. Initial results show graphene quantum dots whose size less than 5 nm were successfully obtained. UV-VIS spectra shows absorption peak around 310 nm. The results of these studies can potentially be used to develop therapies for the eradication of pathogens in open wounds, burns, or skin cancers. New therapies for these conditions are particularly needed when antibiotic-resistant infections are present. NIH KBRIN.

  13. Pale blue dot a vision of the human future in space

    CERN Document Server

    Sagan, Carl

    1994-01-01

    In Cosmos, the late astronomer Carl Sagan cast his gaze over the magnificent mystery of the Universe and made it accessible to millions of people around the world. Now in this stunning sequel, Carl Sagan completes his revolutionary journey through space and time. Future generations will look back on our epoch as the time when the human race finally broke into a radically new frontier--space. In Pale Blue Dot Sagan traces the spellbinding history of our launch into the cosmos and assesses the future that looms before us as we move out into our own solar system and on to distant galaxies beyond. The exploration and eventual settlement of other worlds is neither a fantasy nor luxury, insists Sagan, but rather a necessary condition for the survival of the human race.

  14. Magnetic enhancement of photoluminescence from blue-luminescent graphene quantum dots

    Science.gov (United States)

    Chen, Qi; Shi, Chentian; Zhang, Chunfeng; Pu, Songyang; Wang, Rui; Wu, Xuewei; Wang, Xiaoyong; Xue, Fei; Pan, Dengyu; Xiao, Min

    2016-02-01

    Graphene quantum-dots (GQDs) have been predicted and demonstrated with fascinating optical and magnetic properties. However, the magnetic effect on the optical properties remains experimentally unexplored. Here, we conduct a magneto-photoluminescence study on the blue-luminescence GQDs at cryogenic temperatures with magnetic field up to 10 T. When the magnetic field is applied, a remarkable enhancement of photoluminescence emission has been observed together with an insignificant change in circular polarization. The results have been well explained by the scenario of magnetic-field-controlled singlet-triplet mixing in GQDs owing to the Zeeman splitting of triplet states, which is further verified by temperature-dependent experiments. This work uncovers the pivotal role of intersystem crossing in GQDs, which is instrumental for their potential applications such as light-emitting diodes, photodynamic therapy, and spintronic devices.

  15. Ultrafast Method for Selective Design of Graphene Quantum Dots with Highly Efficient Blue Emission

    Science.gov (United States)

    Kang, Suk Hyun; Mhin, Sungwook; Han, Hyuksu; Kim, Kang Min; Jones, Jacob L.; Ryu, Jeong Ho; Kang, Ju Seop; Kim, Shin Hee; Shim, Kwang Bo

    2016-12-01

    Graphene quantum dots (GQDs) have attractive properties and potential applications. However, their various applications are limited by a current synthetic method which requires long processing time. Here, we report a facile and remarkably rapid method for production of GQDs exhibiting excellent optoelectronic properties. We employed the pulsed laser ablation (PLA) technique to exfoliate GQDs from multi-wall carbon nanotube (MWCNTs), which can be referred to as a pulsed laser exfoliation (PLE) process. Strikingly, it takes only 6 min to transform all MWCNTs precursors to GQDs by using PLE process. Furthermore, we could selectively produce either GQDs or graphene oxide quantum dots (GOQDs) by simply changing the organic solvents utilized in the PLE processing. The synthesized GQDs show distinct blue photoluminescence (PL) with excellent quantum yield (QY) up to 12% as well as sufficient brightness and resolution to be suitable for optoelectronic applications. We believe that the PLE process proposed in this work will further open up new routes for the preparation of different optoelectronic nanomaterials.

  16. Red, Yellow, and Blue Luminescence by Graphene Quantum Dots: Syntheses, Mechanism, and Cellular Imaging.

    Science.gov (United States)

    Gao, Tian; Wang, Xi; Yang, Li-Yun; He, Huan; Ba, Xiao-Xu; Zhao, Jie; Jiang, Feng-Lei; Liu, Yi

    2017-07-26

    Owing to their excellent photoluminescence (PL) properties, good biocompatibility, and low toxicity, graphene quantum dots (GQDs) are widely applied in bioimaging, biosensing, and so forth. However, further development of GQDs is limited by their synthetic methodology and unclear PL mechanism. Therefore, it is urgent to find efficient and universal methods for the synthesis of GQDs with high stability, controllable surface properties, and tunable PL emission wavelength. By coating with polyethyleneimine (PEI) of different molecular weights, blue-, yellow-, and red-emitting GQDs were successfully prepared. By transmission electron microscopy, atomic force microscopy, and dynamic light scattering, the characterization of size and morphology revealed that blue-emitting PEI1800 GQDs were monocoated, like jelly beans, and red-emitting PEI600 GQDs were multicoated, like capsules. The amidation reaction between carboxyl and amide functional groups played an important role in the coating process, as evidenced by IR spectroscopy and theoretical calculation with density functional theory B3LYP/6-31G*. The PL-tunable GQDs exhibited an excellent chemical stability and extremely low cytotoxicity, and they had been shown to be feasible for bioimaging, making these GQDs highly attractive for a wide variety of applications, including multicolor imaging and bioanalysis.

  17. [Psychic disorders and somnolence].

    Science.gov (United States)

    Houeto, J L; Arnulf, I

    2002-12-01

    Hallucinations (mainly visual), psychosis and excessive daytime sleepiness are potential side-effects of dopaminergic treatment. They may require a reduction or suppression of dopaminergic agonists, and the prescription of atypical neuroleptic agents or vigilance-enhancing drugs. The recent description of narcolepsy-like sleep onset in rapid eye movement sleep periods synchronous with hypnagogic hallucinations in patients with dopaminergic-induced psychosis or excessive daytime sleepiness, suggests that the mesodiencephalic lesions may predispose to the psychic effects of dopaminergic treatment. Disease-related mood disorders, sexual compulsions, gambling or levodopa addiction may also be amplified by the antiparkinsonian treatment. These complications illustrate the neuro-psychic aspect of Parkinson's disease: psychic troubles may result from a subtle balance between the direct effects of drugs, the pre-morbid pathological personality and the cortical and subcortical lesions.

  18. Hyaluronic Acid Conjugated Magnetic Prussian Blue@Quantum Dot Nanoparticles for Cancer Theranostics.

    Science.gov (United States)

    Yang, Yongbo; Jing, Lijia; Li, Xiaoda; Lin, Li; Yue, Xiuli; Dai, Zhifei

    2017-01-01

    A multifunctional nanotheranostic agent was developed by conjugating both hyaluronic acid and bovine serum albumin coated CuInS2-ZnS quantum dots onto the surface of magnetic Prussian blue nanoparticles. The obtained nanoagent could serve as an efficient contrast agent to simultaneously enhance near infrared (NIR) fluorescence and magnetic resonance (MR) imaging greatly. The coexistence of magnetic core and CD44 ligand hyaluronic acid was found to largely improve the specific uptake of the nanoagent by CD44 overexpressed HeLa cells upon applying an external magnetic field. Both NIR fluorescence and MR imaging in vivo proved high accumulation of the nanoagent at tumor site due to its excellent CD44 receptor/magnetic dual targeting capability. After intravenous injection of the nanoagent and treatment of external magnetic field, the tumor in nude mice was efficiently ablated upon NIR laser irradiation and the tumor growth inhibition was more than 89.95%. Such nanotheranostic agent is of crucial importance for accurately identifying the size and location of the tumor before therapy, monitoring the photothermal treatment procedure in real-time during therapy, assessing the effectiveness after therapy.

  19. Effect of defects on quantum yield in blue emitting photoluminescent nitrogen doped graphene quantum dots

    Science.gov (United States)

    Kharangarh, Poonam R.; Umapathy, Siva; Singh, Gurmeet

    2017-10-01

    This paper presents a comprehensive study of the impact of defects on quantum yield in Nitrogen doped graphene quantum dots (N-GQDs). The facile and high yielding hydrothermal method was used to process the N-GQDs by selecting two different nitrogen containing powders, that is, NH4Cl (sample-I) and (NH4)2SO4(sample-II). Initially, the synthesized samples were characterized by using High Resolution Transmission Electron Microscope (HRTEM), Powdered X-Ray Diffraction, Raman Spectroscopy, and UV-Visible spectroscopy, Fourier Transform Infrared Spectroscopy, and Photoluminescence (PL) for sample integrity. HRTEM images suggest that the majority of the both sample types were in the narrow range of 5-20 nm in diameter. The samples show blue photoluminescence and excitation dependent PL emission characteristics. As expected, by using the different excitation energy in PL, appearance of peak introduces additional energy levels between π and π* that provide alternative electron transition pathways. The most remarkable finding is that the fluorescence quantum yield is up to 28% for sample-I and is 49.8% for sample-II, which is higher than that of reported GQDs (less than 25%). This clearly suggests that the defect states related to Nitrogen, Chlorine, and Sulfur that alter the band gap of the GQDs determine the PL characteristics and the quantum yield.

  20. Synthesis of blue emitting InP/ZnS quantum dots through control of competition between etching and growth.

    Science.gov (United States)

    Lim, Kipil; Jang, Ho Seong; Woo, Kyoungja

    2012-12-07

    Blue (quantum dots (QDs) are in great demand for various applications. However, their synthesis has been challenging. Here we present blue emitting InP/ZnS core/shell QDs with a band edge emission of 475 nm and a full width at half maximum of 39 nm (215 meV) from their quantum confined states. The drastic temperature drop immediately after mixing of the precursors and holding them at a temperature below 150 °C was the critical factor for the synthesis of blue emitting QDs, because the blue QDs are formed by the etching of ultra-small InP cores by residual acetic acid below 150 °C. Etching was dominant at temperatures below 150 °C, whereas growth was dominant at temperatures above 150 °C. ZnS shells were formed successfully at 150 °C, yielding blue emitting InP/ZnS QDs. The colour of the InP/ZnS QDs depicted on the CIE 1931 chromaticity diagram is located close to the edge, indicating a pure blue colour compared to other InP-based QDs.

  1. Sonocatalytic degradation of methylene blue by a novel graphene quantum dots anchored CdSe nanocatalyst.

    Science.gov (United States)

    Sajjadi, Saeed; Khataee, Alireza; Kamali, Mehdi

    2017-11-01

    Cadmium selenide/graphene quantum dots (CdSe/GQDs) nanocatalyst with small band gap energy and a large specific surface area was produced via a facile three-step sonochemical-hydrothermal process. The features of the as-prepared CdSe, GQDs and CdSe/GQDs samples were characterized by photoluminescence spectroscopy (PL), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), Fourier transformed infrared (FT-IR), diffuse-reflectance spectrophotometer (DRS), and Brunauer-Emmett-Teller (BET) analysis. The sonocatalytic activity of the synthesized CdSe/GQDs was effectively accelerated compared with that of pure CdSe nanoparticles in degradation of methylene blue (MB). The influence of the CdSe/GQDs dosage (0.25-1.25g/L), initial MB concentration (20-30mg/L), initial solution pH (3-12), and ultrasonic output power (200-600W/L) were examined on the sonocatalytic treatment of MB aqueous solutions. The degradation efficiency (DE%) of 99% attained at 1g/L of CdSe/GQDs, 20mg/L of MB, pH of 9, and an output power of 200W/L at 90min of ultrasonic irradiation. Furthermore, DE% increased with addition of K2S2O8 and H2O2 as the enhancers via producing more free radicals. However, addition of sulfate, carbonate, and chloride as radical sweeper decreased DE%. Furthermore, well-reusability of the CdSe/GQDs sonocatalyst was demonstrated for 5 successive runs and some of the sonocatalytic generated intermediates were indicated by GC-MS analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. On Psychic Determinism.

    Science.gov (United States)

    Brown, Robin Gordon

    2017-06-01

    A confusion persists in the psychoanalytic literature regarding the concept of psychic determinism. Two authors are cited in whose works the concept is identified as foundational to psychoanalysis, in the one case as a "fundamental hypothesis" (Charles Brenner) and in the other as an "underlying presupposition" or assumption (Linda A.W. Brakel). Both claims are based on a conflation of the concept Freud had in mind with a philosophical doctrine going by the same name but meaning something quite different. The philosophical doctrine has no place in psychoanalysis at all, and Freud's concept does not play a foundational role there. In a second section a restricted concept of psychic determinism is critically examined. A third section deals with the impact of that restricted concept on clinical theory and contemporary controversies about clinical practice. Finally, some possible reasons for this confusion are suggested.

  3. The pale blue dot a vision of the human future in space uma experiência tradutória

    OpenAIRE

    Matos, Bruno Fernandes Belchior de

    2015-01-01

    O presente Projeto de Mestrado na área de Estudos de Tradução tem por objetivo apresentar uma proposta de tradução comparativa comentada para Português Europeu da seleção de quatro capítulos da obra divulgadora de ciência The Pale Blue Dot – A vision of the human future in space, escrito em 1994 e da autoria de Carl Sagan. Pretende-se dividir este trabalho em dois capítulos distintos. No primeiro capítulo será feita uma breve abordagem autobiográfica do autor da obra, o percurs...

  4. [Prevention of psychic disorders].

    Science.gov (United States)

    Siepmann, M

    2012-06-01

    Prevention aims to avoid the occurrence of psychiatric illness and disability caused by psychic disorders. The relevant interventions refer to the individual, the family context and other environmental factors. Universal and primary prevention target the entire population or a part of this (i. e. students). Secondary and selective intervention should prevent the manifestation of psychiatric disorders in vulnerable individuals (i. e. children with behavioral problems). Tertiary measures aim at preventing the worsening or recurrence of symptoms in individuals who already suffer from mental illness. Within the past 25 years protective and risk factors that reduce or increase the probability of occurrence of mental disorders have increasingly been identified. This results in improved prevention. The present article gives an overview of preventive measures against the most common mental disorders in the light of the current evidence base. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Facile synthesis and step by step enhancement of blue photoluminescence from Ag-doped ZnS quantum dots.

    Science.gov (United States)

    Sahai, Sonal; Husain, Mushahid; Shanker, Virendra; Singh, Nahar; Haranath, D

    2011-05-15

    Our results pertaining to the step by step enhancement of photoluminescence (PL) intensity from ZnS:Ag,Al quantum dots (QDs) are presented. Initially, these QDs were synthesized using a simple co-precipitation technique involving a surfactant, polyvinylpyrrolidone (PVP), in de-ionised water. It was observed that the blue PL originated from ZnS:Ag,Al QDs was considerably weak and not suitable for any practical display application. Upon UV (365 nm) photolysis, the PL intensity augmented to ~170% and attained a saturation value after ~100 min of exposure. This is attributed to the photo-corrosion mechanism exerted by high-flux UV light on ZnS:Ag,Al QDs. Auxiliary enhancement of PL intensity to 250% has been evidenced by subjecting the QDs to high temperatures (200 °C) and pressures (~120 bars) in a sulphur-rich atmosphere, which is due to the improvement in crystallanity of ZnS QDs. The origin of the bright-blue PL has been discussed. The results were supported by X-ray phase analysis, high-resolution electron microscopy and compositional evaluation. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. High Quantum Yield Blue Emission from Lead-Free Inorganic Antimony Halide Perovskite Colloidal Quantum Dots.

    Science.gov (United States)

    Zhang, Jian; Yang, Ying; Deng, Hui; Farooq, Umar; Yang, Xiaokun; Khan, Jahangeer; Tang, Jiang; Song, Haisheng

    2017-09-26

    Colloidal quantum dots (QDs) of lead halide perovskite have recently received great attention owing to their remarkable performances in optoelectronic applications. However, their wide applications are hindered from toxic lead element, which is not environment- and consumer-friendly. Herein, we utilized heterovalent substitution of divalent lead (Pb(2+)) with trivalent antimony (Sb(3+)) to synthesize stable and brightly luminescent Cs3Sb2Br9 QDs. The lead-free, full-inorganic QDs were fabricated by a modified ligand-assisted reprecipitation strategy. A photoluminescence quantum yield (PLQY) was determined to be 46% at 410 nm, which was superior to that of other reported halide perovskite QDs. The PL enhancement mechanism was unraveled by surface composition derived quantum-well band structure and their large exciton binding energy. The Br-rich surface and the observed 530 meV exciton binding energy were proposed to guarantee the efficient radiative recombination. In addition, we can also tune the inorganic perovskite QD (Cs3Sb2X9) emission wavelength from 370 to 560 nm via anion exchange reactions. The developed full-inorganic lead-free Sb-perovskite QDs with high PLQY and stable emission promise great potential for efficient emission candidates.

  7. Hydrothermal synthesis of highly luminescent blue-emitting ZnSe(S) quantum dots exhibiting low toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Mirnajafizadeh, Fatemeh; Ramsey, Deborah; McAlpine, Shelli [School of Chemistry, University of New South Wales, Sydney, NSW 2052 (Australia); Wang, Fan; Reece, Peter [School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Stride, John Arron, E-mail: j.stride@unsw.edu.au [School of Chemistry, University of New South Wales, Sydney, NSW 2052 (Australia); Bragg Institute, Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia)

    2016-07-01

    Highly luminescent quantum dots (QDs) that emit in the visible spectrum are of interest to a number of imaging technologies, not least that of biological samples. One issue that hinders the application of luminescent markers in biology is the potential toxicity of the fluorophore. Here we show that hydrothermally synthesized ZnSe(S) QDs have low cytotoxicity to both human colorectal carcinoma cells (HCT-116) and human skin fibroblast cells (WS1). The QDs exhibited a high degree of crystallinity, with a strong blue photoluminescence at up to 29% quantum yield relative to 4′,6-diamidino-2-phenylindole (DAPI) without post-synthetic UV-irradiation. Confocal microscopy images obtained of HCT-116 cells after incubation with the QDs highlighted the stability of the particles in cell media. Cytotoxicity studies showed that both HCT-116 and WS1 cells retain 100% viability after treatment with the QDs at concentrations up to 0.5 g/L, which makes them of potential use in biological imaging applications. - Highlights: • Highly luminescent ZnSe(S) QDs were synthesized using a simple, one-step hydrothermal method. • The as-synthesized QDs were found to be nontoxic in the presence of biological cells. • The QDs were stable in biological media with identical emission profile to that in water.

  8. A thin CdSe shell boosts the electron transfer from CdTe quantum dots to methylene blue.

    Science.gov (United States)

    Dworak, L; Roth, S; Scheffer, M P; Frangakis, A S; Wachtveitl, J

    2018-01-12

    CdTe core and CdTe/CdSe core/shell quantum dots (QD) are investigated with steady state and time-resolved spectroscopic methods. The coating of the CdTe core with a 0.7 nm thick CdSe shell shifts the lowest exciton absorption band to the red by more than 70 nm making the CdTe/CdSe QD an interesting candidate for application in solar energy conversion. Femtosecond transient absorption measurements are applied to study the photoinduced electron transfer (ET) to the molecular acceptor methylene blue (MB). ET times after single excitation of the QD are determined for different MB : QD ratios. The ET reaction is significantly faster in the case of the MB-CdTe/CdSe QD complexes, indicative of an altered charge distribution in the photoexcited heterostructure with a higher electron density in the CdSe shell. As a result of the efficient absorption of incoming light and the faster ET reaction, the amount of reduced MB in the time resolved experiments is higher for CdTe/CdSe QD compared to CdTe QD.

  9. Green and fast synthesis of amino-functionalized graphene quantum dots with deep blue photoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, E., E-mail: eduardo.blanco@uca.es; Blanco, G.; Gonzalez-Leal, J. M.; Barrera, M. C.; Domínguez, M.; Ramirez-del-Solar, M. [University of Cádiz, Institute of Electron Microscopy and Materials (Spain)

    2015-05-15

    Graphene quantum dots (GQDs) were prepared using a top-down approach with a green microwave-assisted hydrothermal synthesis from ultrathin graphite, previously ultrasound delaminated. Results obtained by transmission electron microscopy and atomic force microscopy indicate that the so-fabricated GQDs are plates with 6 nm of average diameter, mostly single- or bi-layered. Photoluminescence characterization shows that the strongest emission occurs at 410–415 nm wavelength when the samples are excited at 310–320 nm wavelength. In addition to these down-conversion features, GQDs also exhibit up-conversion photoluminescence when excited in the range 560–800 nm wavelength, with broad emission peaks at 410–450 nm wavelength. Analysis of X-ray photoelectron spectroscopy measurements indicates a higher proportion of C–C sp{sup 2} than sp{sup 3} bonds, with the sp{sup 3} ones mainly located at the GQD surfaces. Also evidences of C–O and C–N bonds at the GQD surface have been observed. The combination of these results with Raman and ultraviolet–visible absorption experiments allows envisaging the GQDs to be composed of amino-functionalized sp{sup 2} islands with a high degree of surface oxidation. This would explain the photoluminescent properties observed in the samples under study. The combined up- and down-conversion photoluminescence processes would made these GQDs a powerful energy-transfer component in GQDs–TiO{sub 2} nanocomposite systems, which could be used in photocatalyst devices with superior performance compared to simple TiO{sub 2} systems.

  10. Green and fast synthesis of amino-functionalized graphene quantum dots with deep blue photoluminescence

    Science.gov (United States)

    Blanco, E.; Blanco, G.; Gonzalez-Leal, J. M.; Barrera, M. C.; Domínguez, M.; Ramirez-del-Solar, M.

    2015-05-01

    Graphene quantum dots (GQDs) were prepared using a top-down approach with a green microwave-assisted hydrothermal synthesis from ultrathin graphite, previously ultrasound delaminated. Results obtained by transmission electron microscopy and atomic force microscopy indicate that the so-fabricated GQDs are plates with 6 nm of average diameter, mostly single- or bi-layered. Photoluminescence characterization shows that the strongest emission occurs at 410-415 nm wavelength when the samples are excited at 310-320 nm wavelength. In addition to these down-conversion features, GQDs also exhibit up-conversion photoluminescence when excited in the range 560-800 nm wavelength, with broad emission peaks at 410-450 nm wavelength. Analysis of X-ray photoelectron spectroscopy measurements indicates a higher proportion of C-C sp2 than sp3 bonds, with the sp3 ones mainly located at the GQD surfaces. Also evidences of C-O and C-N bonds at the GQD surface have been observed. The combination of these results with Raman and ultraviolet-visible absorption experiments allows envisaging the GQDs to be composed of amino-functionalized sp2 islands with a high degree of surface oxidation. This would explain the photoluminescent properties observed in the samples under study. The combined up- and down-conversion photoluminescence processes would made these GQDs a powerful energy-transfer component in GQDs-TiO2 nanocomposite systems, which could be used in photocatalyst devices with superior performance compared to simple TiO2 systems.

  11. The Psychology of Psychic Distance

    DEFF Research Database (Denmark)

    Håkanson, Lars; Ambos, Björn; Schuster, Anja

    2016-01-01

    and their theoretical underpinnings assume psychic distances to be symmetric. Building on insights from psychology and sociology, this paper demonstrates how national factors and cognitive processes interact in the formation of asymmetric distance perceptions. The results suggest that exposure to other countries...

  12. [Psychic disorders and somatic suffering].

    Science.gov (United States)

    Canneva, Jean

    2010-01-01

    To what extent should somatic treatment be taken into account when psychic suffering dominates? How can this care be anticipated when healthcare workers and carers are confronted with patients who do not express what they want? Greatest attention must be paid to somatic care by anticipating body function and relying on the support of the families and the skills of the professionals.

  13. Blue single photon emission up to 200 K from an InGaN quantum dot in AlGaN nanowire

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, Saniya; Das, Ayan; Bhattacharya, Pallab [Center for Photonics and Multiscale Nanomaterials, Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109-2122 (United States)

    2013-04-22

    We demonstrate polarized blue single photon emission up to 200 K from an In{sub 0.2}Ga{sub 0.8}N quantum dot in a single Al{sub 0.1}Ga{sub 0.9}N nanowire. The InGaN/AlGaN dot-in-nanowire heterostructure was grown on (111) silicon by plasma assisted molecular beam epitaxy. Nanowires dispersed on a silicon substrate show sharp exciton and biexciton transitions in the micro-photoluminescence spectra. Second-order correlation measurements performed under pulsed excitation at the biexciton wavelength confirm single photon emission, with a g{sup (2)}(0) of 0.43 at 200 K. The emitted photons have a short radiative lifetime of 0.7 ns and are linearly polarized along the c-axis of the nanowire with a degree of polarization of 78%.

  14. Carrier recombination spatial transfer by reduced potential barrier causes blue/red switchable luminescence in C8 carbon quantum dots/organic hybrid light-emitting devices

    Directory of Open Access Journals (Sweden)

    Xifang Chen

    2016-04-01

    Full Text Available The underlying mechanism behind the blue/red color-switchable luminescence in the C8 carbon quantum dots (CQDs/organic hybrid light-emitting devices (LEDs is investigated. The study shows that the increasing bias alters the energy-level spatial distribution and reduces the carrier potential barrier at the CQDs/organic layer interface, resulting in transition of the carrier transport mechanism from quantum tunneling to direct injection. This causes spatial shift of carrier recombination from the organic layer to the CQDs layer with resultant transition of electroluminescence from blue to red. By contrast, the pure CQDs-based LED exhibits green–red electroluminescence stemming from recombination of injected carriers in the CQDs.

  15. Regulation of psychic functions in combat sport

    Directory of Open Access Journals (Sweden)

    Klymenko A.I.

    2010-06-01

    Full Text Available The problems of adjusting of psychical functions are considered in sport. The methods of self-regulation are rotined in sport. The groups of emotional reactions of combat sportsmen are certain. It is set that sporting psychologists and trainers are mainly addressed to training of psychical functions. Also - the system of psychical self-regulation must be complex. It contains affecting physiological reactions and on psychical processes. Five groups of emotional reactions of combat sportsmen are marked. They are directed on development of ability without superfluous emotions to overcome extreme situations in the process of competition activity.

  16. [Fibromyalgia: a disease of psychic trauma?].

    Science.gov (United States)

    El-Hage, Wissam; Lamy, Céline; Goupille, Philippe; Gaillard, Philippe; Camus, Vincent

    2006-11-01

    Chronic unexplained pain may be a somatic manifestation of psychological distress - often untreated distress. The association between psychic trauma, posttraumatic symptoms, psychic dissociation, and somatoform disorders is currently well documented. When examining a patient with chronic pain syndrome, it is important to consider its psychic dimension early on and to look for a history of psychic trauma. This can help avoid prolonged chronic effects and the emergence of psychiatric comorbidity. There is currently no consensual medication strategy for treatment of unexplained chronic pain syndrome. Multidisciplinary outpatient management is necessary in these complex cases, which require simultaneous medical and psychiatric referrals.

  17. For the 2004 DOT, the bottom of the sea is blue; A l'edition 2004 du DOT, le fond de la mer est bleu

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2005-01-15

    This document is an abstract of the conference Deep Offshore Technology (DOT). The main theme discussed are the production increase, the diversification and the democratization of the operators, a real progression of the investments, the end of the 3000 m deep limit and the development of technologies. (A.L.B.)

  18. The Psychic Life of Resistance

    DEFF Research Database (Denmark)

    Barinaga, Ester

    2013-01-01

    The last 20 years have seen a flood of studies of resistance, ranging from collective to individual acts of resistance, from the study of material aspects to its more ideational ones. Yet students of resistance have neglected the psychological dimension of everyday individual acts of resistance...... of Stockholm, Sweden, which is being redeveloped into a high-tech region, it offers empirical insight into the psychic life of resistance. Further, a particular resistance strategy is identified: symbolic dislocations through adherence to a boundary other than the one subjecting the self in the first place....

  19. Brightly near-infrared to blue emission tunable silver-carbon dot nanohybrid for sensing of ascorbic acid and construction of logic gate.

    Science.gov (United States)

    Tian, Tian; Zhong, Yaping; Deng, Chun; Wang, Hao; He, Yu; Ge, Yili; Song, Gongwu

    2017-01-01

    Recently, carbon dots (CDs) have drawn extensive attention owing to their unique properties. While more and more research had been focusing on the exploration of CDs as fluorescence sensors, the blue or green fluorescence emission of CDs restricts further applications of CDs, particularly in the biology-relevant fields due to the commonly blue auto-fluorescence of biological matrix. Therefore, the preparation of CDs with strong emission at long wavelengths is highly desirable. For these situations, a facile, straightforward and extra-reductant needless method was established to fabricate silver-carbon dot nanohybrid with enhanced near-infrared fluorescence through metal-enhanced fluorescence (MEF). We applied the Ag-CD nanohybrid as a probe to detect antioxidants such as ascorbic acid in near-infrared window, and the probe possesses a linear range of 0.2-60μM. More importantly, this sensor could not only function in aqueous solution, but also display well selective response in intricate biological fluids. In addition, an IMPLICATION logic gate was constructed based on the unique characteristics of Ag-CD nanohybrid which presages more opportunities for application in single and multiple biological sensing. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Graphene Quantum Dot Solid Sheets: Strong blue-light-emitting & photocurrent-producing band-gap-opened nanostructures

    National Research Council Canada - National Science Library

    Ganapathi Bharathi; Devaraj Nataraj; Sellan Premkumar; Murugaiyan Sowmiya; Kittusamy Senthilkumar; T Daniel Thangadurai; Oleg Yu Khyzhun; Mukul Gupta; Deodatta Phase; Nirmalendu Patra; Shambhu Nath Jha; Dibyendu Bhattacharyya

    2017-01-01

    .... However, efforts to induce intrinsic optical properties are still in progress. Herein, we report the production of micron-sized sheets by interconnecting graphene quantum dots (GQDs), which are termed ‘GQD solid sheets...

  1. Theodor Waitz on psychic unity.

    Science.gov (United States)

    Jahoda, Gustav

    2014-06-01

    The tolerant stance on 'race' by prominent Enlightenment figures was followed in the 19th century by a powerful wave of biological racism. Many of its proponents took the view that human 'races' constitute separate species, and that most non-white ones are of inferior mentality. An early opponent of this claim was James Cowles Prichard, who used mainly missionary reports in seeking to refute it. Far more extensive work was undertaken by the Herbartian psychologist Theodor Waitz, who collected ethnographic material from all over the world. It was published in six volumes - the last two after his death by his former student Georg Gerland. Waitz aim was to demonstrate the 'psychic unity' of mankind. Initially extracts from the volume on African peoples are presented in order to show how he dealt with his material. The main focus is on his first volume entitled Introduction to Anthropology, in which he elaborates his general thesis. In it Waitz maintains, against the biological racists, that mankind is a single species. Furthermore he discusses the changes from savagery to civilization, attributing them to a combination of geography and history. He was followed by Adolf Bastian who, unlike Waitz, was a great traveller with personal experience of peoples all over the globe. Both firmly believed in the psychic unity of mankind, but Bastian's approach to psychology was very different.

  2. Investigation of the Psychic Space in Psychoanalysis

    OpenAIRE

    I M Kadyrov; O S Shirokova

    2008-01-01

    The paper deals with different aspects of the psychic space in psychoanalysis. The authors suggest a classification of personality types which may be useful in a clinical-psychological research of the psychic space in patients with agora-claustrophobic disorders.

  3. [Psychic disorders and gastrointestinal pathology. Part 2].

    Science.gov (United States)

    Kolesnikov, D B; Rapoport, S I; Voznesenskaia, L A

    2010-01-01

    The problem of nosological forms of somatic diseases associated with psychic disorders is discussed as exemplified by gastrointestinal pathology (duodenal ulcer, ulcerative colitis, irritated bowl syndrome). Implication of such diseases provides a basis for regarding certain pathological conditions as specific clinical variants in which somatic and psychic constituents are integrated into a single morbid complex.

  4. [Constructivism: a characteristic of the psychic process].

    Science.gov (United States)

    Ruiz, R H

    1995-05-01

    Constructivism, more than a posture or a school concept, is a specific feature of the psychic process. The term "specific" needs to be understood taking into account two senses. On the one hand, as a first sense, one must consider it as something inherent to the psychic process. On the other, as a second sense, it means that constructivism in the psychic process has distinctive characteristics: and this make it differ from the concept of constructivism applied in other fields. The fact of considering the psychism as a "construction" lets explain those mental productions such as art and science; as well as madness and crime: possibilities and risks of that construction.

  5. Alternative mitochondrial electron transfer for the treatment of neurodegenerative diseases and cancers: Methylene blue connects the dots.

    Science.gov (United States)

    Yang, Shao-Hua; Li, Wenjun; Sumien, Nathalie; Forster, Michael; Simpkins, James W; Liu, Ran

    2017-10-01

    Brain has exceptional high requirement for energy metabolism with glucose as the exclusive energy source. Decrease of brain energy metabolism and glucose uptake has been found in patients of Alzheimer's, Parkinson's and other neurodegenerative diseases, providing a clear link between neurodegenerative disorders and energy metabolism. On the other hand, cancers, including glioblastoma, have increased glucose uptake and rely on aerobic glycolysis for energy metabolism. The switch of high efficient oxidative phosphorylation to low efficient aerobic glycolysis pathway (Warburg effect) provides macromolecule for biosynthesis and proliferation. Current research indicates that methylene blue, a century old drug, can receive electron from NADH in the presence of complex I and donates it to cytochrome c, providing an alternative electron transfer pathway. Methylene blue increases oxygen consumption, decrease glycolysis, and increases glucose uptake in vitro. Methylene blue enhances glucose uptake and regional cerebral blood flow in rats upon acute treatment. In addition, methylene blue provides protective effect in neuron and astrocyte against various insults in vitro and in rodent models of Alzheimer's, Parkinson's, and Huntington's disease. In glioblastoma cells, methylene blue reverses Warburg effect by enhancing mitochondrial oxidative phosphorylation, arrests glioma cell cycle at s-phase, and inhibits glioma cell proliferation. Accordingly, methylene blue activates AMP-activated protein kinase, inhibits downstream acetyl-coA carboxylase and cyclin-dependent kinases. In summary, there is accumulating evidence providing a proof of concept that enhancement of mitochondrial oxidative phosphorylation via alternative mitochondrial electron transfer may offer protective action against neurodegenerative diseases and inhibit cancers proliferation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Tapping the potential of trioctylphosphine (TOP) in the realization of highly luminescent blue-emitting colloidal indium phosphide (InP) quantum dots

    Science.gov (United States)

    Singh, Akanksha; Chawla, Parul; Jain, Shefali; Sharma, Shailesh Narain

    2017-06-01

    In this work, extremely small blue emitting colloidal InP-based quantum dots (size 2-5 nm) have been synthesized using trioctylphosphine (TOP) as a source of phosphorus. The method reported here is unconventional, quite rapid ( 90 min), more viable, less expensive and relatively greener as compared to other conventional methods that employ tristrimethylsilyylphosphine(P(SiMe3)3) which is scarce, expensive, flammable, highly toxic and even banned in a few countries. Highly luminescent InP QDs having bluish-green emission (λ 490 nm) can be synthesized using this method without resorting to any post-synthesis etching to tune the emission to the blue region. Besides being the source of phosphorus and the particle size regulating agent, the efficacy of TOP is further realized during synthesis via its reduction of indium salt, which aids in the formation of indium metal and then subsequently in the development of InP QDs. The PL intensity of as-synthesized InP QDs is further enhanced by growing a shell of wide band gap material, i.e. ZnS resulting in a concurrent increment in quantum yield from 25% to 38% respectively.

  7. Rheumatoid arthritis as psychic problem

    Directory of Open Access Journals (Sweden)

    Jiří Kaas

    2014-01-01

    Full Text Available The article deals with the issue of psychic problems of rheumatoid arthritis patients. Rheumatoid arthritis is a chronic, inflammatory motor system disease with comprehensive impact on the patient's life. The disease is often considered an exclusively physical disease. But such approach is insufficient because the disease is accompanied by motor limitations of different intensities, by pain and by fatigue that cause considerable exhaustion to the patient. The patients often must give up their hobbies and in some cases even their jobs. In most serious cases, even common daily activities including self–servicing actions become an obstacle to the patient. It is therefore logical that the psyche of a patient with such disease is considerably strained. One of the partial goals of the study consisted in mapping the subjectively perceived quality of life of rheumatoid arthritis patients in facet 8, "negative feelings", and in ascertaining whether there is statistically significant relation to facets 1, "pain and discomfort", and 2, "energy and fatigue". Another goal consisted in comparing the subjectively perceived quality of life between men and women with rheumatoid arthritis, as well as between population of rheumatoid arthritis patients and control healthy population. The study was implemented within the research project of the Grant Agency of the University of South Bohemia in České Budějovice number 120/2012/S, „Reflection of quality of life in nursing", under use of two standardized questionnaires, WHOQOL–100 and HAQ. This article presents exclusively the data acquired based on the WHOQOL–100 questionnaire. The research set consisted of patients suffering from rheumatoid arthritis from all over the Czech Republic. The size of the set was determined by a statistician at 200 individuals suffering from the disease, in a ratio of 150 women and 50 men. The selection set was derived from the basic set of rheumatoid arthritis patients and

  8. Rheumatoid arthritis as psychic problem

    Directory of Open Access Journals (Sweden)

    Jiří Kaas

    2014-12-01

    Full Text Available The article deals with the issue of psychic problems of rheumatoid arthritis patients. Rheumatoid arthritis is a chronic, inflammatory motor system disease with comprehensive impact on the patient's life. The disease is often considered an exclusively physical disease. But such approach is insufficient because the disease is accompanied by motor limitations of different intensities, by pain and by fatigue that cause considerable exhaustion to the patient. The patients often must give up their hobbies and in some cases even their jobs. In most serious cases, even common daily activities including self-servicing actions become an obstacle to the patient. It is therefore logical that the psyche of a patient with such disease is considerably strained. One of the partial goals of the study consisted in mapping the subjectively perceived quality of life of rheumatoid arthritis patients in facet 8, "negative feelings", and in ascertaining whether there is statistically significant relation to facets 1, "pain and discomfort", and 2, "energy and fatigue". Another goal consisted in comparing the subjectively perceived quality of life between men and women with rheumatoid arthritis, as well as between population of rheumatoid arthritis patients and control healthy population. The study was implemented within the research project of the Grant Agency of the University of South Bohemia in České Budějovice number 120/2012/S, "Reflection of quality of life in nursing", under use of two standardized questionnaires, WHOQOL-100 and HAQ. This article presents exclusively the data acquired based on the WHOQOL-100 questionnaire. The research set consisted of patients suffering from rheumatoid arthritis from all over the Czech Republic. The size of the set was determined by a statistician at 200 individuals suffering from the disease, in a ratio of 150 women and 50 men. The selection set was derived from the basic set of rheumatoid arthritis patients and can

  9. Synthesis of blue-photoluminescent graphene quantum dots/polystyrenic anion-exchange resin for Fe(III) detection

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wenjun, E-mail: wjzhang@hebut.edu.cn; Gan, Jie

    2016-05-30

    Highlights: • GQD/PS-AER was prepared as a solid fluorescent sensor with millimeter size. • The GQD/PS-AER sensor could detect Fe{sup 3+} ions selectively. • The GQD/PS-AER sensor could be reusable. • This method is simple and economical. - Abstract: A novel solid fluorescent sensor with millimeter size, based on graphene quantum dots/polystyrenic anion-exchange resin (GQDs/PS-AER) was obtained for the detection of Fe{sup 3+}. The linear response range of Fe{sup 3+} was obtained from 1 μM to 7 μM and the detection limit was as low as 0.65 μM. In addition, the sensor could be regenerated by adding complexing agent EDTA and be separated by using simple filtration.

  10. [The psychic structure of chronic pain patients].

    Science.gov (United States)

    Fischer-Kern, Melitta; Mikutta, Christian; Kapusta, Nestor D; Hörz, Susanne; Naderer, Andrea; Thierry, Nikolaus; Leithner-Dziubas, Katharina; Löffler-Stastka, Henriette; Aigner, Martin

    2010-01-01

    The study investigates the psychic structure and psychiatric comorbidity of chronic pain patients according to Kernberg's concept of personality organization. We assessed 48 chronic pain patients attending the Behavioural Medicine Pain Clinic in the Department of Psychiatry. Patients were diagnosed using the SCID (DSM-IV). Psychic structure was assessed using the Structured Interview of Personality Organization (STIPO). At least one psychiatric diagnosis was found in 94 % of the patients, and 63 % of the patients met the criteria of at least one diagnosis of a personality disorder. In 58 % of the patients, we diagnosed a borderline personality organization, with high deficits in the dimensions of coping, defence mechanisms and identity. The high prevalence of borderline personality organization confirms the importance of a diagnostic investigation of the psychic structure and the necessity for psychotherapeutic treatment in chronic pain patients.

  11. Psychic reality and the interpretation of transference.

    Science.gov (United States)

    Caper, R

    1997-01-01

    Beginning with Freud's concept of psychic reality as the product of external events and the patient's unconscious fantasies, the author suggests that projective identification, as described by Klein, gives an account of how these two elements combine to produce one's psychic reality. The transference is an aspect of psychic reality that represents a confusion between the patient and one of his or her objects--the analyst--brought about by projective identification. A clinical example illustrates how the patient's transformation of the analyst's interpretations through projective identification contributes to the transference. Analysis of the transference in the analytic relationship allows patients to experience their role in the formation of their experience of the world, "live" and as it happens. This promotes the integration of the patient's personality. The author compares this approach with other approaches to the transference.

  12. Polypyrrole and graphene quantum dots @ Prussian Blue hybrid film on graphite felt electrodes: Application for amperometric determination of l-cysteine.

    Science.gov (United States)

    Wang, Lei; Tricard, Simon; Yue, Pengwei; Zhao, Jihua; Fang, Jian; Shen, Weiguo

    2016-03-15

    A novel polypyrrole (PPy) and graphene quantum dots (GQDs) @ Prussian Blue (PB) nanocomposite has been grafted on a graphite felt (GF) substrate (PPy/GQDs@PB/GF), and has been proven to be an efficient electrochemical sensor for the determination of l-cysteine (l-cys). GQDs, which were fabricated by carbonization of citric acid and adsorbed on GF surface ultrasonically, played an important role for promoting the synthesis process of PB via a spontaneous redox reaction between Fe(3+) and [Fe(CN)6](3-). The PPy film has been electro-polymerized to improve the electrochemical stability of the PPy/GQDs@PB/GF electrode. The as-prepared electrode was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), infrared spectroscopy (IR), X-ray diffraction (XRD) and electrochemical methods. It exhibited an excellent activity for the electrocatalytic oxidation of l-cys, with a detection sensitivity equal to 0.41 Amol(-1) L for a concentration range of 0.2-50 μmolL(-1), and equal to 0.15 Amol(-1) L for a concentration range of 50-1000 μmolL(-1). A low detection limit of 0.15 μmolL(-1), as well as a remarkable long-time stability and a negligible sensitivity to interfering analytes, were also ascertained. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Polyethylene glycol-coated blue-emitting silicon dots with improved properties for uses in aqueous and biological environments.

    Science.gov (United States)

    Rodríguez Sartori, Damián; Lillo, Cristian R; Romero, Juan J; Laura Dell Arciprete, María; Miñán, Alejandro; Fernández Lorenzo de Mele, Mónica; Gonzalez, Mónica C

    2016-11-25

    Grafting of polyethylene glycol (PEG) to ultrasmall photoluminescent silicon dots (SiDs) is expected to improve and expand the applications of these particles to aqueous environments and biological systems. Herein we report a novel one-pot synthesis of robust, highly water compatible PEG-coated SiDs (denoted as PEG-SiDs) of (3.3 ± 0.5) nm size. The nanoparticles' synthesis is based on the liquid phase oxidation of magnesium silicide using PEG as reaction media and leading to high PEG density grafting. PEG-SiDs enhanced photophysical, photosensitising, and solution properties in aqueous environments are described and compared to those of 2 nm size PEG-coated SiDs with low PEG density grafting (denoted as PEG-NHSiDs) obtained from a multistep synthesis strategy. PEG-SiDs form highly dispersed suspensions in water showing stable photoluminescence and quantum yields of Φ = 0.13 ± 0.04 at 370 nm excitation in air-saturated suspensions. These particles exhibited the capacity of photosensitising the formation of singlet molecular oxygen, not observed for PEG-NHSiDs. PEG robust shielding of the silicon core luminescent properties is further demonstrated in bio-imaging experiments stressing the strong interaction between PEG-SiDs and Staphylococcus aureus smears by observing the photoluminescence of particles. PEG-SiDs were found to be nontoxic to S. aureus cells at concentrations of 100 mg ml(-1), though a bacteriostatic effect on S. aureus biofilms was observed upon UV-A irradiation under conditions where light alone has no effect.

  14. An Approximation to the Characterization of Psychic Atmosphere as a Psychic Development Factor in Pregnant Teenagers

    Directory of Open Access Journals (Sweden)

    Nubia Torres

    2008-05-01

    Full Text Available This study intends to characterize psychic atmosphere as a psychic development factor in pregnant teenagers. The case research in a qualitative approach was used within the framework of the clinical psychoanalytic method. 6 pregnant teenagers with ages between 14 and 17 years, from a low socio-economic level were chosen, whose pregnancies were not a result of sexual abuse and who belonged to the “Pregnant and breastfeeding mothers” of the Tunjuelito Secretary for Social Integration’s Local subdirection in Bogotá. Three in-depth interviews were carried out with each individual.The psychic atmosphere of the pregnant teenagers has contributed tostopping psychic development altogether in 5 cases, and to its deterioration in the other case.

  15. Essential Thrombocytosis Following Multiple Psychic Traumas

    Directory of Open Access Journals (Sweden)

    Rezvan Sadr Mohammadi

    2014-09-01

    Full Text Available The associations between exposure to traumatic events and psychiatric disorders such as posttraumatic stress disorder (PTSD, depression, and anxiety have been established. It is important that clinicians notice to this phenomenon and avoid from inappropriate interpretations and additional laboratory tests. Here, a case of 45-year-old man with Essential thrombocytosis developed after multiple psychic traumas was introduced.

  16. [Mutation voice disorders conditioned by psychic factors].

    Science.gov (United States)

    Wojciechowska, Anna; Obrebowski, Andrzej; Studzińska, Katarzyna; Swidziński, Piotr

    2010-01-01

    The case of 17 year old boy with mutational falsetto conditioned by a complex of psychic factors particulary with personality disorders and strong emotional bond with his mother was described. Phonation exercises lowered the average voice pitch. The stable results of phoniatric rehabilitation is dependent on effectiveness of psychological therapy of the whole family. Acoustic voice analysis demonstrates objectively the results of rehabilitation.

  17. Essential Thrombocytosis Following Multiple Psychic Traumas

    OpenAIRE

    Sadr Mohammadi, Rezvan; Mahdian, Mehrdad; Bidaki, Reza; Mostafavi, Seyed-Ali

    2014-01-01

    The associations between exposure to traumatic events and psychiatric disorders such as posttraumatic stress disorder (PTSD), depression, and anxiety have been established. It is important that clinicians notice to this phenomenon and avoid from inappropriate interpretations and additional laboratory tests. Here, a case of 45-year-old man with Essential thrombocytosis developed after multiple psychic traumas was introduced.

  18. Essential Thrombocytosis Following Multiple Psychic Traumas.

    Science.gov (United States)

    Sadr Mohammadi, Rezvan; Mahdian, Mehrdad; Bidaki, Reza; Mostafavi, Seyed-Ali

    2014-01-01

    The associations between exposure to traumatic events and psychiatric disorders such as posttraumatic stress disorder (PTSD), depression, and anxiety have been established. It is important that clinicians notice to this phenomenon and avoid from inappropriate interpretations and additional laboratory tests. Here, a case of 45-year-old man with Essential thrombocytosis developed after multiple psychic traumas was introduced.

  19. The study of normal psychic life

    NARCIS (Netherlands)

    Pol, A.J.J. van de; Derksen, J.J.L.

    2014-01-01

    In the introduction to his Allgemeine Psychopathologie, published in 1913, Karl Jaspers stated that psychology has little value for the psychopathologist because it focuses on all kinds of interesting matters, but not on normal psychic life. In this article we argue that today, in the year 2013,

  20. Psychic Distance, Innovation, and Firm Performance

    NARCIS (Netherlands)

    Azar, Goudarz; Drogendijk, Rian

    2014-01-01

    Previous research suggests that internationalization improves a firm's ability to innovate, but the effect of internationalizing into specific target markets or destinations on the innovation ability of firms has not been fully investigated. This study examined whether the psychic distance between

  1. Psychic disorders in former prisoners of war.

    Science.gov (United States)

    Babić, Dragan; Sinanović, Osman

    2004-01-01

    To analyze the kind and the representation of psychic disorders in former prisoners of war and war veterans who were not detained in camps. The analyzed sample consisted of 160 respondents divided into two groups. A group of 100 former prisoners of war and a group of 60 war veterans who had not been detained in camps. All the respondents are males and were psychically in healthy condition prior to the war. The modified Harvard Trauma Questionnaire was used to diagnose traumatic experience, and a questionnaire according to the DSM IV criteria was used to diagnose posttraumatic stress disorder. The Depressiveness Scale D-92 was used to diagnose depressiveness; the questionnaire STAI was used to diagnose anxiety; CAGE Questionnaire was used to diagnose alcoholism. The former prisoners of war had traumatic experience at a higher level as compared to the war veterans who had not been detained in camps (P disorder was diagnosed in 52% of camp inmates and 31.7% of war veterans (P psychic disorders (PTSD and depressiveness) in the former prisoners of war as compared to the war veterans.

  2. Pure psychic akinesia with bilateral lesions of basal ganglia.

    Science.gov (United States)

    Laplane, D; Baulac, M; Widlöcher, D; Dubois, B

    1984-01-01

    Three patients showed dramatic psychic akinesia after recovery from toxic encephalopathy. They had no or only mild motor disorders. The spontaneous psychic akinesia was reversible when the patient was stimulated, as if there was a loss of self psychic activation. Intellectual capacities were normal. Two patients had stereotyped behaviours resembling compulsions. In all patients CT cans showed bilateral lesions in the basal ganglia, mainly within the globus pallidus. Images PMID:6726263

  3. Pure psychic akinesia with bilateral lesions of basal ganglia.

    OpenAIRE

    Laplane, D; Baulac, M; Widlöcher, D; Dubois, B

    1984-01-01

    Three patients showed dramatic psychic akinesia after recovery from toxic encephalopathy. They had no or only mild motor disorders. The spontaneous psychic akinesia was reversible when the patient was stimulated, as if there was a loss of self psychic activation. Intellectual capacities were normal. Two patients had stereotyped behaviours resembling compulsions. In all patients CT cans showed bilateral lesions in the basal ganglia, mainly within the globus pallidus.

  4. Psychical research and the origins of American psychology

    Science.gov (United States)

    Sommer, Andreas

    2012-01-01

    Largely unacknowledged by historians of the human sciences, late-19th-century psychical researchers were actively involved in the making of fledgling academic psychology. Moreover, with few exceptions historians have failed to discuss the wider implications of the fact that the founder of academic psychology in America, William James, considered himself a psychical researcher and sought to integrate the scientific study of mediumship, telepathy and other controversial topics into the nascent discipline. Analysing the celebrated exposure of the medium Eusapia Palladino by German-born Harvard psychologist Hugo Münsterberg as a representative example, this article discusses strategies employed by psychologists in the United States to expel psychical research from the agenda of scientific psychology. It is argued that the traditional historiography of psychical research, dominated by accounts deeply averse to its very subject matter, has been part of an ongoing form of ‘boundary-work’ to bolster the scientific status of psychology. PMID:23355763

  5. Unlocking Creativity: Connections between Psychic and External Reality.

    Science.gov (United States)

    Rodenhauser, Paul

    1994-01-01

    Focuses on associations between creative temperament and clinical disorder, while addressing the enigmatic and alluring nature of creativity. Considers relationships between psychic and external realities, between artists and society, and between artists and therapists. (SR)

  6. Postpartum Blues

    Science.gov (United States)

    ... Home > Pregnancy > Postpartum care > Baby blues after pregnancy Baby blues after pregnancy E-mail to a friend Please ... tell your health care provider. What are the baby blues? Baby blues are feelings of sadness a woman ...

  7. The psychic envelopes in psychoanalytic theories of infancy.

    Science.gov (United States)

    Mellier, Denis

    2014-01-01

    This paper aims to review the topic of psychic envelopes and to sketch the main outlines of this concept in infancy. We first explore the origins of the concept in Freud's "protective shield" and then its development in adult psychoanalysis before going on to see how this fits in infancy with post-Bionian psychoanalysis and development. Four central notions guide this review: (1) Freud's "protective shield" describes a barrier to protect the psychic apparatus against potentially overflowing trauma. It is a core notion which highlights a serious clinical challenge for patients for whom the shield is damaged or faulty: the risk of confusion of borders between the internal/external world, conscious/unconscious, mind/body, or self-conservation/sexuality. (2) Anzieu's "Skin-Ego" is defined by the different senses of the body. The different layers of experienced sensation, of this body-ego, go on to form the psychic envelope. This theory contributes to our understanding of how early trauma, due to the failures of maternal care, can continue to have an impact in adult life. (3) Bick's "psychic skin" establishes the concept in relation to infancy. The mother's containing functions allow a first psychic skin to develop, which then defines an infant's psychic space and affords the infant a degree of self-containment. Houzel then conceptualized this process as a stabilization of drive forces. (4) Stern's "narrative envelope" derives from the intersection between psychoanalysis and neuroscience. It gives us another way to conceptualize the development of pre-verbal communication. It may also pave the way for a finer distinction of different types of envelopes. Ultimately, in this review we find that psychic envelopes in infancy can be viewed from four different perspectives (economic, topographical, dynamic, and genetic) and recommend further investigation.

  8. The psychic envelopes in psychoanalytic theories of infancy.

    Directory of Open Access Journals (Sweden)

    Denis eMellier

    2014-07-01

    Full Text Available This paper aims to review the topic of psychic envelopes and to sketch the main outlines of this concept in infancy. We first explore the origins of the concept in Freud's 'protective shield' and then its development in adult psychoanalysis before going on to see how this fits in infancy with post-Bionian psychoanalysis and development. Four central notions guide this review:1 Freud's protective shield describes a barrier to protect the psychic apparatus against potentially overflowing trauma. It is a core notion which highlights a serious clinical challenge for patients for whom the shield is damaged or faulty: the risk of confusion of borders between the internal/external world, conscious/unconscious, mind/body, or self-conservation/sexuality.2 Anzieu's Skin-Ego is defined by the different senses of the body. The different layers of experienced sensation, of this body-ego, go on to form the psychic envelope. This theory contributes to our understanding of how early trauma, due to the failures of maternal care, can continue to have an impact in adult life. 3 Bick's psychic skin establishes the concept in relation to infancy. The mother’s containing functions allow a first psychic skin to develop, which then defines an infant’s psychic space and affords the infant a degree of self-containment. Houzel then conceptualized this process as a stabilization of drive forces.4 Stern's narrative envelope derives from the intersection between psychoanalysis and neuroscience. It gives us another way to conceptualise the development of pre-verbal communication. It may also pave the way for a finer distinction of different types of envelopes.Ultimately, in this review we find that psychic envelopes in infancy can be viewed from four different perspectives (economic, topographical, dynamic and genetic and recommend further investigation.

  9. Psychological means of recreation sportsmen’s psychic workability

    Directory of Open Access Journals (Sweden)

    Gant H.Y.

    2016-10-01

    Full Text Available Purpose: to study recreation of sportsmen’s psychic workability under influence of psychological methods. Material: Students-sportsmen, practicing boxing and kickboxing (n=45, age17-23 years participated in he research. Express assessment methodic for “Self-feeling, activity and mood”, “Correcting tests” was used. Results: sportsmen’s subjective assessment of own state depends on the stage of competition functioning. This assessment is rather favorable in pre-competition and competition periods. In pre-competition period unconscious weakening of psychic workability happens. Psychic workability weakening in competition period is of functional character and can be reduced in post-competition period. Conclusions: application of art-therapeutic methodic results in sportsmen’s more recreated, relaxed and hardy. Singing and drawing can be used as the method of stabilization of sportsmen’s activity, mood and self-feeling.

  10. Pathological organizations and psychic retreats in eating disorders.

    Science.gov (United States)

    Kadish, Yael Adira

    2012-04-01

    A set of characteristic symptoms allow for the relatively straightforward diagnosis of eating disorders. Simultaneously and paradoxically, underlying the eating disorders are a wide variety of personality organizations/disorders, stretching from the neurotic to the borderline and narcissistic, and even to conditions approaching psychosis. This paper will argue that the inherent commonalities can be ascribed to pathological organizations of a similar nature and quality, operational across the spectrum of eating disorders and functioning in a particular, sadomasochistic way. The typical forms that eating disorders take are based on the specific ways that food and the body are used, that is, symptom manifestation. These distinctive symptom manifestations appear to be related to Steiner's (1982, 1993) notion of a psychic retreat. Pathological organizations and psychic retreats are latent until called upon either sporadically or continuously. When activated, these defensive structures operate like a complex psychic skeleton around which the unique psychodynamics of each patient become rearranged and thereby transformed.

  11. Ambroise August Liébeault and psychic phenomena.

    Science.gov (United States)

    Alvarado, Carlos S

    2009-10-01

    Some nineteenth-century hypnosis researchers did not limit their interest to the study of the conventional psychological and behavioral aspects of hypnosis, but also studied and wrote about psychic phenomena such as mental suggestion and clairvoyance. One example, and the topic of this paper, was French physician Ambroise August Liébeault (1823-1904), who influenced the Nancy school of hypnosis. Liébeault wrote about mental suggestion, clairvoyance, mediumship, and even so-called poltergeists. Some of his writings provide conventional explanations of the phenomena. Still of interest today, Liébeault's writings about psychic phenomena illustrate the overlap that existed during the nineteenth-century between hypnosis and psychic phenomena--an overlap related to the potentials of the mind and its subconscious activity.

  12. [Personality and psychic deadaptation of airline pilots with neurocirculatory dystonia].

    Science.gov (United States)

    Krapivnitskaia, T A

    2006-01-01

    In-depth clinical psychological investigation of airline pilots with neurocirculatory dystonia (n=194, mean age 38.57 +/- 0.85) and essentially healthy control pilots (n=183, mean age 38.4+/-0.92) revealed distinctive features in NCD pilots' mentality and behavior including personality, interpersonal communication, type of thinking, stress reaction, protection tactics, and mental dysfunctions. Psychic deadaptation such as symptoms of psychic asthenia, paranoia, depression, schizophrenia, and impulsive behavior had a negative effect on the clinical course and led to medical disqualification of 15% of NCD pilots.

  13. [Clinical characteristic of schizoaffective disorders developed after psychic trauma].

    Science.gov (United States)

    Alekseev, A V; Shmilovich, A A

    2008-01-01

    Seventy-four patients with schizoaffective disorder caused by psychic trauma (a basic group) and 51 patients with spontaneous manifestation of this disorder (a comparison group) have been studied. The prevalence of personality traits of inhibited spectrum with predisposition to affective disorders and psychogenic reactions were observed in the patients of the basic group. Situations of emotional deprivation were the most frequent content of mental stress. The psychic trauma exerts a provoking, pathoplastic and pathokinetic effect in schizoaffective disorder. Three variants of the course of schizoaffective disorder after emotional stress have been singled out: with psychogenic neurotic manifestation, with psychogenic psychotic manifestation (psychogenic reactive depression type) and with endogenous manifestation.

  14. Silica-Coated Mn-Doped CsPb(Cl/Br)3 Inorganic Perovskite Quantum Dots: Exciton-to-Mn Energy Transfer and Blue-Excitable Solid-State Lighting.

    Science.gov (United States)

    Chen, Daqin; Fang, Gaoliang; Chen, Xiao

    2017-11-22

    Tunability of emitting colors of perovskite quantum dots (PQDs) was generally realized via composition/size modulation. Due to their bandgap absorption and ionic crystal features, the mixing of multiple PQDs inevitably suffers from reabsorption and anion-exchange effects. Herein, we address these issues with high-content Mn2+-doped CsPbCl3 PQDs that can yield blue-excitable orange Mn2+ emission benefited from exciton-to-Mn energy transfer and Cl-to-Br anion exchange. Silica-coating was applied to improve air stability of PQDs, suppress the loss of Mn2+, and avoid anion-exchange between different PQDs. As a direct benefit of intense multicolor emissions from Mn2+-doped PQD@SiO2 solid phosphors, a prototype white light-emitting diode with excellent optical performance and superior light stability was constructed using green CsPbBr3@SiO2 and orange Mn: CsPb(Cl/Br)3@SiO2 composites as color converters, verifying their potential applications in the field of optoelectronics.

  15. Characterization of the interaction of a mono-6-thio-β-cyclodextrin-capped CdTe quantum dots-methylene blue/methylene green system with herring sperm DNA using a spectroscopic approach.

    Science.gov (United States)

    Shen, Yizhong; Liu, Shaopu; Wang, Lei; Yin, Pengfei; He, Youqiu

    2014-11-01

    Novel, water-soluble CdTe quantum dots (QDs) capped with β-cyclodextrin (β-CD) and ~ 4.0 nm in diameter were synthesized in aqueous solution, and characterized using transmission electron microscopy (TEM). A fluorescence-sensing system based on the photoinduced electron transfer (PET) of (mono-6-thio-β-CD)-CdTe QDs was then designed to measure the interaction of phenothiazine dyes [methylene blue (MB) and methylene green (MG)] with herring sperm DNA (hsDNA). This fluorescence-sensing system was based on a fluorescence "OFF-ON" mode. First, MB/MG adsorbed on the surface of (mono-6-thio-β-CD)-CdTe QDs effectively quenches the fluorescence of (mono-6-thio-β-CD)-CdTe QDs through PET. Then, addition of hsDNA restores the fluorescence intensity of (mono-6-thio-β-CD)-CdTe QDs, because hsDNA can bind with MB/MG and remove it from the as-prepared (mono-6-thio-β-CD)-CdTe QDs. In addition, detailed reaction mechanisms of the (mono-6-thio-β-CD)-CdTe QDs-MB/MG-hsDNA solution system were studied using optical methods, by comparison with the TGA-CdTe QDs-MB/MG-hsDNA solution system. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Psychic and moral exhaustion in primary care workers

    Directory of Open Access Journals (Sweden)

    Priscilla Brandão Bacci Pegoraro

    2017-12-01

    Full Text Available Abstract OBJECTIVE To report the experience of developing a workshop proposal to assist local managers with the identification, management and prevention of primary care workers' psychic and moral exhaustion. METHOD The workshop was developed through a literature review performed between November 2014 and June 2015. The temporal cut considered studies of the ten previous years. The selection included studies describing collective interventions for situations generating psychic and moral exhaustion, preferably in primary care services. RESULTS Thirty-five articles were analyzed. The workshop provides five meetings with an average duration of one hour. The themes are: awareness; recognizing personal stress; dealing with personal stress; recognizing team stress; and dealing with team stress. The workshop is based on five key principles: detection and coping; attention to interpersonal relationships; communication; self-knowledge and mindfulness. CONCLUSION Psychic and moral exhaustion may reflect negatively on workers' health, the care, and the organization. The proposal of measures to recognize, deal with and prevent psychic and moral exhaustion is relevant and strategic in the constant search for improvement of satisfaction and quality.

  17. Prussian Blue

    Science.gov (United States)

    ... Groups Resources for Emergency Health Professionals Training & Education Social Media What’s New Preparation & ... Prussian blue work? Who can take Prussian blue? How is Prussian blue given? What are the side effects of Prussian blue? Where can I get Prussian ...

  18. 77 FR 55895 - Permanent Closure of Cincinnati Blue Ash Airport

    Science.gov (United States)

    2012-09-11

    ... Federal Aviation Administration Permanent Closure of Cincinnati Blue Ash Airport AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of permanent closure of Cincinnati Blue Ash Airport (ISZ). SUMMARY: The... Cincinnati advising that on August 29, 2012, it was permanently closing Cincinnati Blue Ash Airport (ISZ...

  19. [Medicolegal Assessment of Psychic Sequelae after Minor Traumatic Events].

    Science.gov (United States)

    Widder, Bernhard

    2017-04-01

    The majority of medicolegal assessments in claimed psychic sequelae after accidents concerns minor traumatic events. In this case, the focus is on three questions: Was the event appropriate to cause a traumatic disturbance according to current psychiatric classification systems (especially current DSM-5)? Which psychical or physical initial injury can be proven beyond reasonable doubt ("full proof") according to German law? What is the impact of personality characteristics and competing life events in the development and maintenance of the mental disorder? Causality between mental disorders and minor traumatic events is to be confirmed especially in the case of persistent physical accident sequelae, but attention has to be paid to the differences in the various legal requirements. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Psychic skin: psychotic defences, borderline process and delusions.

    Science.gov (United States)

    Schmidt, Martin

    2012-02-01

    In this paper, I apply the concept of psychic skin to analytic work with people suffering from personality disorders and psychoses. When psychoses emerge, the defensive skin which protects the ego is breached and violent unconscious forces rip through the personality. Some of the patients diagnosed as schizophrenic with whom I work have identified with archetypal characters such as Christ, Satan, John Lennon and the Queen. I attempt to show how the adoption of these inflated personas can serve as secondary psychic skins. Such delusional identifications can provide a protective shield to hide the denuded self and prevent intrusion from the external world. Through clinical example, I try to demonstrate how these archetypal 'second skins' can preserve life until internal and external conditions make it possible for the self to emerge. I contrast such psychotic identifications with 'thin-skinned' and 'thick-skinned' narcissism as well as 'defences of the self' in borderline states where the psychic skin may be damaged but does not disintegrate. I also look at the ways in which Jung's own personal experience was different from this and how he managed to avert psychotic breakdown. © 2012, The Society of Analytical Psychology.

  1. [Clinical, prognostic, and preventive significance of "premorbid" psychic states in adolescents and youths (observational study)].

    Science.gov (United States)

    Chubarovskiĭ, V V

    2009-01-01

    This paper presents results of observational, clinico-epidemiological, and catamnestic studies including 856 adolescents and youths attending schools, professional and higher education institutions in Moscow. The data are analysed in terms of the prevalence, structure, and dynamics of different borderline psychic states depending on age. The frequency of "premorbid" psychic abnormalities in adolescents is shown to be 52.6% compared with 15.46% in youths. It is argued that subclinical psychic disorders in adolescents have more favourable prognosis and should be regarded as adaptive reactions to the processes associated with physiological pubertal crisis. Recommendations are proposed for differential primary and secondary prophylaxis of age-related premorbid psychic states.

  2. Characterizing Pale Blue Dots Around FGKM Stars

    Science.gov (United States)

    Rugheimer, S.; Kaltenegger, L.; Sasselov, D. D.; Segura, A.

    2015-12-01

    Exoplanet characterization of small rocky worlds will be a main focus in the coming decades. For future telescopes like JWST and UVOIR/HDST, an exoplanet's host star will influence our ability to detect and interpret spectral features, including biosignatures. We present a complete suit of stellar models and a grid of model atmospheres for Earth-like planets at equivalent stages of geological evolution in their HZ for stellar effective temperature from Teff = 2300K to 7000K, sampling the entire FGKM stellar type range. Since M dwarfs are simultaneously the most numerous in the universe, the most active, and the most likely stars to host terrestrial exoplanets, we focus in particular on the range of UV emission possible in each sub M spectral class. The UV emission from a planet's host star dominates the photochemistry and thus the resultant observable spectral features of the planet. Using the latest UV spectra obtained by HST and IUE we model the effect of stellar activity on Earth-like planets. We also model the amount of UV flux reaching the surface for Earth-like planets at various geological epochs ranging from a pre-biotic world through the rise of oxygen and for Earth-like planets orbiting FGKM stars at equivalent stages of evolution. When modeling the remotely detectable spectra of these planets we focus on the primary detectable atmospheric features that indicate habitability on Earth, namely: H2O, CO2, O3, CH4, N2O and CH3Cl. We model the emergent as well as transit spectra of Earth-like planets orbiting our grid of FGKM stars in the VIS/NIR (0.4 - 4 μm) and the IR (5 - 20 μm) range as input for future missions like JWST and concepts like UVOIR/HDST.

  3. Varieties of Voice-Hearing: Psychics and the Psychosis Continuum

    Science.gov (United States)

    Powers, Albert R.; Kelley, Megan S.; Corlett, Philip R.

    2017-01-01

    Hearing voices that are not present is a prominent symptom of serious mental illness. However, these experiences may be common in the non-help-seeking population, leading some to propose the existence of a continuum of psychosis from health to disease. Thus far, research on this continuum has focused on what is impaired in help-seeking groups. Here we focus on protective factors in non-help-seeking voice-hearers. We introduce a new study population: clairaudient psychics who receive daily auditory messages. We conducted phenomenological interviews with these subjects, as well as with patients diagnosed with a psychotic disorder who hear voices, people with a diagnosis of a psychotic disorder who do not hear voices, and matched control subjects (without voices or a diagnosis). We found the hallucinatory experiences of psychic voice-hearers to be very similar to those of patients who were diagnosed. We employed techniques from forensic psychiatry to conclude that the psychics were not malingering. Critically, we found that this sample of non-help-seeking voice hearers were able to control the onset and offset of their voices, that they were less distressed by their voice-hearing experiences and that, the first time they admitted to voice-hearing, the reception by others was much more likely to be positive. Patients had much more negative voice-hearing experiences, were more likely to receive a negative reaction when sharing their voices with others for the first time, and this was subsequently more disruptive to their social relationships. We predict that this sub-population of healthy voice-hearers may have much to teach us about the neurobiology, cognitive psychology and ultimately the treatment of voices that are distressing. PMID:28053132

  4. A laboratory investigation of telepathy: the study of a psychic.

    Science.gov (United States)

    Moss, T; Eveloff, H H; Chang, A F

    A series of experiments in psychic phenomena were undertaken with a 21-year-old man who claimed to have telepathic ability. An elaborate procedure was devised to render collusion between Transmitters and Receiver ineffective, if not impossible. Results tended to support the subject's claims. Several single responses are reported which seemed particularly noteworthy with respect to correlation in time and content. A Control subject, duplicating the experimental procedure, did not have the overall success rate demonstrated by the experimental subject. The authors conclude that this experiment strongly suggests the possibility of telepathy, but does not prove it.

  5. Behavior Problems of Psychic Nature in Shelter - Reared Dogs

    Directory of Open Access Journals (Sweden)

    Mehmed Yuksel Halil

    2016-10-01

    Full Text Available This review summarizes the etiology, the species and the prevalence of pathoethological processes of psychic nature in sheltered dogs. The analysis was performed on the mandatory necessity of establishing the type of the dog’s temperament, in relation to the owners’ proper approach towards the specific animal, as well as its successful primary and secondary socialisation. A neurotic dog may exhibit chronic anxiety, fear, hyperactivity, obsessive behavior, and inappropriate responses to stimuli. Truly psychotic dogs, however, are deranged. Their behavior is acute and unpredictable.

  6. The Role of Psychic Distance in International Trade

    DEFF Research Database (Denmark)

    Håkanson, Lars

    2014-01-01

    international trade in three categories of goods among 25 major trading nations for the period 1962-2008, employing structural equation modeling, incorporating the mutual interdependence of the distance measures. Findings – Exporters’ perceptions are more important for trade in differentiated products than...... and more intense competition from foreign rivals. Originality/value – The paper employs simultaneously a statistical methodology novel to the field and – for the first time in the literature – asymmetric measures of psychic distances as perceived by importers and exporters, respectively. Applying...

  7. The scientific and spiritual implications of psychic abilities.

    Science.gov (United States)

    Targ, R; Katra, J

    2001-01-01

    Since ancient times, spiritual teachers have described paths and practices that a person could follow to achieve health, happiness, and peace of mind. Considerable recent research has indicated that any sort of spiritual practice is likely to improve one's prognosis for recovering from a serious illness. Many of these approaches to spirituality involve learning to quiet the mind rather than adhering to a prescribed religious belief. These meditative paths include the mystic branches of Buddhism, Hinduism, and Christianity; Kabalistic Judaism; Sufism; and many others. What is hinted at in the subtext of these teachings is that as one learns to quiet his or her mind, one is likely to encounter psychic-seeming experiences or perceptions. For example, in The Sutras of Patanjali, the Hindu master tells us that on the way to transcendence we may experience all sorts of amazing visions, such as the ability to see into the distance, or into the future, and to diagnose illnesses and to cure them. However, we are told not to get attached to these psychic abilities--they are mere phenomena standing as stumbling blocks on the path to enlightenment. In this article, we describe the laboratory evidence for some of these remarkable phenomena and their implications for science, mental health, and peace of mind.

  8. Developing Psychic Income in School Administration: The Unique Role School Administrators Can Play

    Science.gov (United States)

    Guramatunhu-Mudiwa, Precious; Scherz, Susan Day

    2013-01-01

    This concept article discusses the importance of developing psychic income as an administrative strategy to enhance the context of school environments and to curb high teacher turnover. The hope is to promote further debate and research in order to establish the extent to which psychic income influences retention rates in hard-to-staff schools.…

  9. Kind of Blue - Europa Blues

    DEFF Research Database (Denmark)

    Mortensen, Tore; Kirkegaard, Peter

    2009-01-01

    Bidraget reflekterer over sammenhænge mellem to værker fra det musikalske og litterære område. Det drejer sig om Miles Davis' Kind of Blue fra 1959 og Arne Dahls krimi, Europa Blues fra 2001. Den grundlæggende indfaldsvinkel er det performative, den frie, men samtidigt disciplinerede musikalske...

  10. [Psychopathology of miscarriages and psychic disorders following fertility treatments].

    Science.gov (United States)

    Leal Herrero, Fernando

    2009-01-01

    This paper deals with the psychic disorders that frequently follow miscarriages. We specify the clinical forms under which such disorders appear and argue in favour of establishing a "Post-Abortion Syndrome" which would include the symptoms that form the basis of the psychopathological reactions that follow miscarriages. We will also study the psychological and psychopathological reactions to be found in couples -in both men and women-, who undergo fertility treatments, offering a brief description of the psychodynamic aspects that affect the couple. Furthermore, we will stress the biological and psychological risks that appear as a consequence of fertility treatments and offer an ethical evaluation of these risks, warning of the long-term consequences of human reproductive techniques.

  11. [The effect of psychic stress on the immune response].

    Science.gov (United States)

    Zimecki, Michał; Artym, Jolanta

    2004-03-24

    Linkage between the central nervous system and the immune system is obvious and is accomplished through the hypothalamus-pituitary-adrenal (HPA) and sympathetic-adrenal medullary (SAM) axes. This review focuses on the effects of psychic stress in animals and humans on immune system function. The effects of stress depend on its duration, type, and intensity. Generally, mild stress enhances the immune response. The effects of stress also depend on the animal's behavioral profile, genetic background and preexposure to stressful conditions. Prenatal stress modifies the immune response of the offspring. Stress also modifies autoimmune reactions in animals and humans. Knowledge of the mediators and their receptors involved in the functioning of the HPA and SAM axes allows pharmacological intervention to alleviate the harmful effects of stress on the immune system. Our studies revealed a benefit of oral lactoferrin application in reversing stress-induced changes in the humoral and cellular immune response in mice.

  12. Haunted thoughts of the careful experimentalist: psychical research and the troubles of experimental physics.

    Science.gov (United States)

    Noakes, Richard

    2014-12-01

    This paper analyses the relationship between the 'elusive' science of psychical research and experimental physics in the period approximately, 1870-1930. Most studies of the relationship between psychical research and the established sciences have examined the ways in which psychical researchers used theories in the established sciences to give greater plausibility to their interpretations of such puzzling phenomena as telepathy, telekinesis and ectoplasm. A smaller literature has examined the use of laboratory instruments to produce scientific evidence for these phenomena. This paper argues that the cultures of experiment in the established science of physics could matter to psychical research in a different way: it suggests that experience of capricious effects, recalcitrant instruments and other problems of the physical laboratory made British physicists especially sympathetic towards the difficulties of the spiritualistic séance and other sites of psychical enquiry. In the wake of widely-reported claims that the mediums they had investigated had been exposed as frauds, these scientific practitioners were eventually persuaded by the merits of an older argument that human psychic subjects could not be treated like laboratory hardware. However, well into the twentieth century, they maintained that experimental physics had important lessons for psychical researchers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. The luminescence profile of carbon dots synthesized from α-cellulose under different acid hydrolysis conditions

    Science.gov (United States)

    Ng, Yann Huey; Chin, Suk Fun; Pang, Suh Cem; Ng, Sing Muk

    2017-08-01

    This work reports the study on the luminescence properties portrayed by carbon dots synthesized under different acid hydrolysis conditions. Sulphuric acid was employed to dehydrate and carbonize α-cellulose as starting precursor. We revealed that the emissions of carbon dots were strongly dependent on the reaction condition during the synthesis, which include hydrolysis time and temperature. Initial mild acid hydrolysis at 4 °C and followed by incubation at room temperature was found favourable to the production of carbon dots emitting green fluorescence, whereas higher temperatures of 50 and 70 °C would produce carbon dots emitting blue fluorescence. At fixed temperature of 50 °C, prolonged synthesis time could shift the emission of carbon dots from green to blue. The green emission was recorded to have a peak at 500 nm when excited at 450 nm; whereas the highest intensity for the blue emission was recorded at 456 nm when excited at 357 nm. Both as-synthesized carbon dots showed excitation-independent emission. The quantum yields for the green and blue carbon dots were evaluated to be 6.4% and 4.0% respectively. The carbon dots emitting blue emission was of better photostability as compared to the carbon dots emitting green fluorescence. Both types of carbon dots synthesized in this study showed significant pH-dependent trend with higher intensity at lower pH condition.

  14. Electro-absorption of silicene and bilayer graphene quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Abdelsalam, Hazem, E-mail: hazem.abdelsalam@etu.u-picardie.fr [Laboratory of Condensed Matter Physics, University of Picardie, Amiens 80039 (France); Department of Theoretical Physics, National Research Center, Cairo 12622 (Egypt); Talaat, Mohamed H. [Physics Department, Faculty of Science, Ain Shams University, Cairo (Egypt); Lukyanchuk, Igor [Laboratory of Condensed Matter Physics, University of Picardie, Amiens 80039 (France); L. D. Landau Institute for Theoretical Physics, Moscow (Russian Federation); Portnoi, M. E. [School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Saroka, V. A., E-mail: v.saroka@exeter.ac.uk [School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Institute for Nuclear Problems, Belarusian State University, Bobruiskaya 11, 220030 Minsk (Belarus)

    2016-07-07

    We study numerically the optical properties of low-buckled silicene and AB-stacked bilayer graphene quantum dots subjected to an external electric field, which is normal to their surface. Within the tight-binding model, the optical absorption is calculated for quantum dots, of triangular and hexagonal shapes, with zigzag and armchair edge terminations. We show that in triangular silicene clusters with zigzag edges a rich and widely tunable infrared absorption peak structure originates from transitions involving zero energy states. The edge of absorption in silicene quantum dots undergoes red shift in the external electric field for triangular clusters, whereas blue shift takes place for hexagonal ones. In small clusters of bilayer graphene with zigzag edges the edge of absorption undergoes blue/red shift for triangular/hexagonal geometry. In armchair clusters of silicene blue shift of the absorption edge takes place for both cluster shapes, while red shift is inherent for both shapes of the bilayer graphene quantum dots.

  15. On the early history of male hysteria and psychic trauma. Charcot's influence on Freudian thought.

    Science.gov (United States)

    Libbrecht, K; Quackelbeen, J

    1995-10-01

    This paper discusses the influence of Jean-Martin Charcot's views on Sigmund Freud's early theory of hysteria and the notion of psychical trauma. We consider the early history of both psychical trauma and male hysteria, for in Charcot's view traumatic hysteria and male hysteria are identical. Freud's two 1886 lectures on male hysteria, delivered after his return from Paris, are crucial to the subject because they present Freud's first impressions of Charcot and his teaching. Some of the ideas presented in the two lectures foreshadow Freud's later generalization of the etiological role of trauma and his theory of the role of psychical trauma in the genesis of hysteria; that is, each hysterical symptom is due to a psychical trauma reviving an earlier traumatic event--the so-called principle of deferred action (Nachträglichkeit). Several arguments substantiate the thesis that Freud's notion of psychical (sexual) trauma was developed in reference to Charcot's notion of traumatic hysteria, and that the early psychoanalytic theory of psychical trauma is clearly indebted to Freud's encounter with Charcot's male traumatic hysterical patients. The discussed Freudian development points out the major role of (physical) traumata in eliciting psychopathological pictures and in this way is of definite historical relevance for the present-day discussion on the traumatic nature of the so-called multiple personality syndrome and other dissociative disorders, and post-traumatic stress disorders.

  16. Sertraline in generalized anxiety disorder: efficacy in treating the psychic and somatic anxiety factors.

    Science.gov (United States)

    Dahl, A A; Ravindran, A; Allgulander, C; Kutcher, S P; Austin, C; Burt, T

    2005-06-01

    The objective was to study the efficacy of sertraline on symptoms of psychic and somatic anxiety in patients suffering from moderate-to-severe generalized anxiety disorder (GAD). Out-patients with DSM-IV GAD were randomized to 12 weeks of double-blind treatment with placebo. The psychic and somatic anxiety factors of the Hamilton Anxiety Rating Scale (HAM-A) and the Quality of Life, Enjoyment, and Satisfaction Questionnaire were analyzed. Treatment with sertraline resulted in significantly greater last observation carried forward (LOCF)-endpoint improvement than placebo on both the HAM-A psychic and somatic anxiety factors. At LOCF-endpoint, all items on the HAM-A psychic factor were more improved on sertraline than placebo, as were three of seven items on the somatic factor. Reduction of secondary depressive symptoms was more correlated with endpoint improvement in quality of life than either psychic- or somatic anxiety. Sertraline treatment demonstrated efficacy for both the psychic and somatic anxiety symptoms of GAD.

  17. Psychical and psychological characteristics of patients with nonepileptic

    Directory of Open Access Journals (Sweden)

    Hassan Awad

    2011-08-01

    Full Text Available Aim To explore psychic and psychological characteristics of patientssuffering from non- epileptic seizures and compare them with the patients suffering from epilepsy. Methods Using medical documentation 40 patients with non epileptic seizures were compared with 40 randomly selected epilepsy patients according to psychiatric and psychological report, and using psychotropic medications. Results Both psychiatric and psychological reports have shown that pathologic changes were more frequently found within the epilepsy group (n = 20 and n=7, respectively than in non-epileptic fits group (n= 18 and n=4, respectively. Six patients had neurotic disorders within the epilepsy group, versus 3 within the non-epileptic fits group. Conversion disorders were more frequently foundwithin the non-epileptic group (n=6 as compared to epilepsy group (n=2. Disorders due to acute reaction to stress occurred in six patients in the non-epileptic fits group versus three patients in theepilepsy group. Cognitive disorders were found more frequently within the epilepsy group (n=6 as compared to the non-epilepticfits group (n=1. Vulnerable character, adolescence crisis, deficitof social abilities and indifference were more frequently foundwithin the non-epileptic fits group (n=3 in comparison with theepilepsy group (n=1. Conclusion Psychiatric and psychological reports are most important elements in the diagnostic of psychogenic non-epilepticseizures.

  18. [The imaginary in the psychic reality. Psychotherapeutic applications].

    Science.gov (United States)

    Aisenson Kogan, A

    1983-12-01

    Imagery is considered an important psychotherapeutic means in many contemporary systems, in an explicit way, or implicitely. Its function is at least double. On the one hand it detains the development of personal possibilities, for it raises an unreal barrier of transference when confronting new experiences, but on the other it amplifies life by extending it towards what Gaston Bachelard calls "a reality of superabundance". It represents the discovery of new facets in the external world but, much more important in psychotherapy, the revelation of unknown aspects of oneself. Thus, for explorative aims imagery is used in tests, interviews and even anamnesis, and for furthering the cure (insight and growth) in systems such as psychodrama, Desoille's waking dreams, sensitivity training and others. The question arises: what is the source of its effectivity? In my opinion it depends on two influences: 1) images, as symbols, constitute "intermediary objects" which permit a confrontation comparatively free of anxiety with oneself and above all to envisage new forms of behaviour. These can even be rehearsed in some psychodramatic techniques or in laboratories; 2) symbols give access to psychical areas which are forbidden to a conceptual approach. Therefore, I suggest that the conquest of one's reality results, paradoxically, from incursions in unreality.

  19. Highly fluorescent xerogels with entrapped carbon dots for organic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Quaranta, A., E-mail: quaranta@ing.unitn.it [University of Trento, Department of Industrial Engineering, via Mesiano, 77, 38123 Trento (Italy); Laboratori Nazionali di Legnaro, INFN, Viale dell' Università, 2, 35020 Legnaro (PD) (Italy); Carturan, S. [Laboratori Nazionali di Legnaro, INFN, Viale dell' Università, 2, 35020 Legnaro (PD) (Italy); University of Padova, Department of Physics and Astronomy “Galileo Galilei”, Via Marzolo, 8, 35131 Padova (Italy); Campagnaro, A.; Dalla Palma, M. [University of Trento, Department of Industrial Engineering, via Mesiano, 77, 38123 Trento (Italy); Laboratori Nazionali di Legnaro, INFN, Viale dell' Università, 2, 35020 Legnaro (PD) (Italy); Giarola, M.; Daldosso, N. [University of Verona, Department of Informatics, Strada le Grazie,15, 37134 Verona (Italy); Maggioni, G. [Laboratori Nazionali di Legnaro, INFN, Viale dell' Università, 2, 35020 Legnaro (PD) (Italy); University of Padova, Department of Physics and Astronomy “Galileo Galilei”, Via Marzolo, 8, 35131 Padova (Italy); Mariotto, G. [University of Verona, Department of Informatics, Strada le Grazie,15, 37134 Verona (Italy)

    2014-02-28

    Organically modified silicate thin film and bulk samples were prepared using [3-(2-aminoethylamino)propyl]trimethoxysilane (AEAP-TMOS) as precursor with the addition of different amounts of AEAP-TMOS functionalized C-dots, prepared by reaction of AEAP-TMOS and citric acid at high temperature. The synthesis of surface functionalized C-dots was followed by Fourier Transform Infrared (FTIR) spectroscopy, and the C-dots optical properties were characterized by optical absorption and UV–vis fluorescence. Thin xerogel films and bulk samples were studied by FTIR, Raman and fluorescence spectroscopy. Intense blue-green emission was observed by UV excitation of functionalized C-dots. Carbon quantum dot (CQD) luminescence was preserved also in the xerogel matrices, and the energy transfer from the matrix to CQDs, which is a key characteristic for scintillation detectors, was investigated in the two systems. - Highlights: • Functionalized carbon dots were synthesized. • Carbon dots were dispersed in hybrid xerogel bulk and thin film. • Carbon dots exhibit a strong tunable blue luminescence. • Xerogels were characterized by FT-IR, Raman and fluorescence spectroscopies. • Energy transfer processes were evidenced between C-dots and xerogel matrix.

  20. DOT's CAFE rulemaking analysis.

    Science.gov (United States)

    2013-02-13

    Presentation discusses what DOT needs to consider in setting CAFE standards. How DOT's use of the CAFE Compliance and Effects Modeling System helps to analyze potential CAFE Standards. How DOT might approach the next round of CAFE standards for model...

  1. A Single Molecule Investigation of the Photostability of Quantum Dots

    DEFF Research Database (Denmark)

    Christensen, Eva Arnspang; Kulatunga, Pasad; Lagerholm, B. Christoffer

    2012-01-01

    Quantum dots (QDs) are very attractive probes for multi-color fluorescence applications. We report here however that single QDs that are subject to continuous blue excitation from a 100W mercury arc lamp will undergo a continuous blue-switching of the emission wavelength eventually reaching a per...... is especially detrimental for multi-color single molecule applications, as we regularly observe spectral blue-shifts of 50 nm, or more even after only ten seconds of illumination.......Quantum dots (QDs) are very attractive probes for multi-color fluorescence applications. We report here however that single QDs that are subject to continuous blue excitation from a 100W mercury arc lamp will undergo a continuous blue-switching of the emission wavelength eventually reaching...

  2. The Psychic Distance Concept: A Review of 25 Years of Research (1990–2015

    Directory of Open Access Journals (Sweden)

    Mariola Ciszewska-Mlinaric

    2016-03-01

    Full Text Available Purpose: There have been numerous studies analyzing the role of psychic (and cultural distance in the internationalization process focused on relationships between distance and market selection, entry mode, or subsidiary performance. Still, cumulative findings of this body of research are mixed and inconclusive. Thus, this review aims for a rigorous presentation of past research on psychic distance, with particular focus on the aspects of international business operations affected by psychic distance in the light of empirical studies.Methodology: This review encompasses 55 papers, both empirical and conceptual, published between 1990–2015 in top IB, international marketing, and management journals. In general, the papers under review were published in 27 journals, with the vast majority of them being published in 2005 or later. The vast majority of reviewed papers are of empirical character (47 papers, while eight are conceptual.Findings: Since 2005, the number of articles published in top academic journals that featured the term “psychic distance” in the title has quadrupled. Common research topics include not only the core domain of internationalization process and performance, but also focus on understanding the concept of psychic distance, analyzing its antecedents and coping modes. Other studies have addressed the performance implications of psychic distance in conjunction with variables like strategy adaptation to foreign markets.Research limitations/implications: While the present review is limited in the number of papers taken into account, it does provide an initial overview of the structure of the field. However, the comparability of findings of different studies is limited by factors such as firm samples or presence of multicultural nations. In terms of directions for further research, promising topics include the relationship between perceived and ‘real’ distances or the effectiveness of different coping modes

  3. Posthuman blues

    CERN Document Server

    Tonnies, Mac

    2013-01-01

    Posthuman Blues, Vol. I is first volume of the edited version of the popular weblog maintained by author Mac Tonnies from 2003 until his tragic death in 2009. Tonnies' blog was a pastiche of his original fiction, reflections on his day-to-day life, trenchant observations of current events, and thoughts on an eclectic range of material he culled from the Internet. What resulted was a remarkably broad portrait of a thoughtful man and the complex times in which he lived, rendered with intellige...

  4. Leg symptoms of somatic, psychic, and unexplained origin in the population-based Bonn vein study.

    Science.gov (United States)

    Amsler, F; Rabe, E; Blättler, W

    2013-08-01

    To assess the somatic and psychic components of venous-type leg symptoms. The psychic versus somatic venous disease questionnaire (PsySoVDQ) was applied to 1,800 participants of the Bonn Vein Study (BVS) II. Factor analysis of the PsySoVDQ made it possible to distinguish a psychic component (PC; 5 items, Cronbach's alpha = 0.73) separate from a somatic component (SC; 4 items, Cronbach's alpha = 0.67). The PC reflected anxiety and inhibition, was prevalent in 39.8% and explained 7.3% of the BVS findings. Higher PC scores were typically found in younger, slim women of higher social status, with feelings of leg heaviness and tension, and reduced psychic quality of life. The SC prevailed in 37.4% and explained 16.5% of BVS findings. Typical SC scorers were older, overweight women with lower social status, more symptoms (including swelling), signs of chronic venous insufficiency, ultrasound-documented venous abnormalities, and reduced multidimensional quality of life. The SC's predictive accuracy for CEAP 2 and 3 (classification according to clinical findings, etiology, anatomy, pathophysiology) was equal to that of the BVS assessment. The PsySoVDQ identified somatic and psychic components of the widespread and frequently reported leg symptoms in the general population. Nevertheless, in the majority of subjects symptoms remained unexplained. A neuropsychological and neurobiological hypothesis is advanced. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  5. Psychic and somatic anxiety differentially predict response to light therapy in women with seasonal affective disorder.

    Science.gov (United States)

    MacKenzie, Bronwyn; Levitan, Robert D

    2005-10-01

    To examine whether psychic and/or somatic anxiety predict responsiveness to light therapy in women with winter Seasonal Affective Disorder (SAD). Eighty-one women with SAD were administered a standard 10-day trial of light therapy administered for one-half hour in the early morning. Using a multiple regression model, baseline somatic and psychic anxiety item scores were used to predict percentage change scores on the 29-item SIGH-SAD post treatment. Baseline scores for weight gain, hypersomnia and the total SIGH-SAD were also included as predictor variables. The regression model was highly significant (F=4.63, df=5,75; p=.001; model R(2)=.236), with both psychic anxiety and somatic anxiety contributing significantly to the model. Consistent with prior work using anti-depressant medication in non-seasonal depression, psychic anxiety was positively correlated with outcome, while somatic anxiety negatively predicted outcome. In SAD, psychic and somatic anxiety scores at baseline appear to be independent and opposite predictors of light therapy response. These effects were independent of baseline scores for weight gain and hypersomnia, two previously established predictors of response to light. These findings may be an important consideration in the design and interpretation of light therapy studies of SAD.

  6. Generation of singlet oxygen and other radical species by quantum dot and carbon dot nanosensitizers

    Science.gov (United States)

    Generalov, Roman; Christensen, Ingeborg L.; Chen, Wei; Sun, Ya-Ping; Kristensen, Solveig; Juzenas, Petras

    2009-06-01

    Medicinal applications of luminescent semiconductor quantum dots are of growing interest. In spite of the fact that their fabrication and imaging applications have been extensively investigated for the last decade, very little is documented on photodynamic action of quantum dots. In this study we demonstrate generation of singlet oxygen and other radical species upon exposure of quantum dots to blue light and therapeutic red light. Extent of radical production can be readily modified by antioxidants. Lay and scientific communities are two sites concerning potential hazards and enthusiastic applications of nanotechnology. Synthesis of quantum dots composed of less toxic materials is of great interest. A new candidate is a ubiquitous element carbon, which on nanoscale exhibits strong photoluminescence.

  7. Quantum dot spectroscopy

    DEFF Research Database (Denmark)

    Leosson, Kristjan

    1999-01-01

    Semiconductor quantum dots ("solid state atoms") are promising candidates for quantum computers and future electronic and optoelectronic devices. Quantum dots are zero-dimensional electronic systems and therefore have discrete energy levels, similar to atoms or molecules. The size distribution...... of quantum dots, however, results in a large inhomogeneous broadening of quantum dot spectra.Work on self-assembled InGaAs/GaAs quantum dots will be presented. Properties of atom-like single-dots states are investigated optically using high spatial and spectral resolution. Single-dot spectra can be used...

  8. Quantum dot spectroscopy

    DEFF Research Database (Denmark)

    Leosson, Kristjan

    Semiconductor quantum dots ("solid-state atoms") are promising candidates for quantum computers and future electronic and optoelectronic devices. Quantum dots are zero-dimensional electronic systems and therefore have discrete energy levels, similar to atoms or molecules. The size distribution...... of quantum dots, however, results in a large inhomogeneous broadening of quantum dot spectra. Work on self-assembled InGaAs/GaAs quantum dots will be presented. Properties of atom-like single-dot states are investigated optically using high spatial and spectral resolution. Single-dot spectra can be used...

  9. Quantum-dot-in-perovskite solids

    KAUST Repository

    Ning, Zhijun

    2015-07-15

    © 2015 Macmillan Publishers Limited. All rights reserved. Heteroepitaxy - atomically aligned growth of a crystalline film atop a different crystalline substrate - is the basis of electrically driven lasers, multijunction solar cells, and blue-light-emitting diodes. Crystalline coherence is preserved even when atomic identity is modulated, a fact that is the critical enabler of quantum wells, wires, and dots. The interfacial quality achieved as a result of heteroepitaxial growth allows new combinations of materials with complementary properties, which enables the design and realization of functionalities that are not available in the single-phase constituents. Here we show that organohalide perovskites and preformed colloidal quantum dots, combined in the solution phase, produce epitaxially aligned \\'dots-in-a-matrix\\' crystals. Using transmission electron microscopy and electron diffraction, we reveal heterocrystals as large as about 60 nanometres and containing at least 20 mutually aligned dots that inherit the crystalline orientation of the perovskite matrix. The heterocrystals exhibit remarkable optoelectronic properties that are traceable to their atom-scale crystalline coherence: photoelectrons and holes generated in the larger-bandgap perovskites are transferred with 80% efficiency to become excitons in the quantum dot nanocrystals, which exploit the excellent photocarrier diffusion of perovskites to produce bright-light emission from infrared-bandgap quantum-tuned materials. By combining the electrical transport properties of the perovskite matrix with the high radiative efficiency of the quantum dots, we engineer a new platform to advance solution-processed infrared optoelectronics.

  10. [Psychic power and energy. Relation of self-experience and concept formation in Freudian theory].

    Science.gov (United States)

    Schott, H G

    1983-01-01

    The concept of psychic energy is very important for the development of Sigmund Freud's theory. It is linked with the problem of psychic power. Both terms--"energy" (Energie) and "power" (Kraft)--are studied within the context of Freud's scientific work. There is a fundamental relation of introspection in practice and scientific description in theory. This relation is reconstructed in three ways: analysis of "psychic work" (psychische Arbeit) as an implication of the self-analysis in Freud's "Interpretation of Dreams"; analysis of the psychological techniques of psychotherapy Freud used; and analysis of the metapsychological theory with its concept of "psychich apparatus" (psychischer Apparat). This interpretation stresses the close relationship of Freud's personal experience as a therapist and self-analyst and his scientific theory with its neurophysiological and psychological terminology.

  11. Connecting dots

    DEFF Research Database (Denmark)

    Murakami, Kyoko; Jacobs, Rachel L.

    2017-01-01

    and Middleton, 1995). A reminiscence conversation is a dynamic talk-in-interaction, which can produce valuable learning experience for the participants involved. Reminiscence talk contains rich, personal, historic data that can reveal and inform family members of an unknown past. In this seminar/chapter, we......Reminiscence is a self-reflecting process on past events and experiences. Not only does it enable past experiences to be brought to light through talk, but it also creates an affective environment, which allows participants to explore and construct a representation of the self (Buchanan...... of connecting the dots of recalled moments of individual family members lives and is geared towards building a family’s shared future for posterity. Lastly, we consider a wider implication of family reminiscence in terms of human development. http://www.infoagepub.com/products/Memory-Practices-and-Learning...

  12. Synthesis and unique photoluminescence properties of nitrogen-rich quantum dots and their applications.

    Science.gov (United States)

    Chen, Xiuxian; Jin, Qingqing; Wu, Lizhu; Tung, ChenHo; Tang, Xinjing

    2014-11-10

    Nitrogen-rich quantum dots (N-dots) were serendipitously synthesized in methanol or aqueous solution at a reaction temperature as low as 50 °C. These N-dots have a small size (less than 10 nm) and contain a high percentage of the element nitrogen, and are thus a new member of quantum-dot family. These N-dots show unique and distinct photoluminescence properties with an increasing percentage of nitrogen compared to the neighboring carbon dots. The photoluminescence behavior was adjusted from blue to green simply through variation of the reaction temperature. Furthermore, the detailed mechanism of N-dot formation was also proposed with the trapped intermediate. These N-dots have also shown promising applications as fluorescent ink and biocompatible staining in C. elegans. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Fluorescent carbon nanomaterials: "quantum dots" or nanoclusters?

    Science.gov (United States)

    Dekaliuk, Mariia O; Viagin, Oleg; Malyukin, Yuriy V; Demchenko, Alexander P

    2014-08-14

    Despite many efforts, the mechanisms of light absorption and emission of small fluorescent carbon nanoparticles (C-dots) are still unresolved and are a subject of active discussion. In this work we address the question as to whether the fluorescence is a collective property of these nanoparticles or they are composed of assembled individual emitters. Selecting three types of C-dots with "violet", "blue" and "green" emissions and performing a detailed study of fluorescence intensity, lifetime and time-resolved anisotropy as a function of excitation and emission wavelengths together with the effect of viscogen and dynamic fluorescence quencher, we demonstrate that the C-dots represent assemblies of surface-exposed fluorophores. They behave as individual emitters, display electronic anisotropy, do not exchange their excited-state energies via homo-FRET and possibly display sub-nanosecond intra-particle mobility.

  14. ‘Spiritalismus vincit Mundum’ Dutch spiritualism and the beginning of psychical research

    Directory of Open Access Journals (Sweden)

    Ingrid Kloosterman

    2014-11-01

    Full Text Available The science of psychical research and parapsychology stemmed, among other things, from wonder about the phenomena of spiritualism: manifestations of the deceased through mediums in séances. In the Netherlands, academic psychical research emerged in 1919, when the Studievereeniging voor Psychical Research (SPR was founded. In this paper, it is argued that a revival of the popularity of spiritualism during the war contributed to the emergence of the Dutch SPR shortly after the First World War had ended. Mass bereavement does not suffice as an explanation for the growth of the spiritualistic movement in the neutral Netherlands in the war years. It is demonstrated that in the writings of spiritualists about the First World War persistent fin-de-siècle themes can be distinguished. Before and during the First World War Dutch spiritualism was dominated by ‘ideologically’ inclined spiritualists and their more ‘critical-scientific’ counterparts were a minority. This had hindered the development of Dutch psychical research. After the war spiritualists shared their hopeful and optimistic perspective of the human soul with scholars leaning towards psychoanalytical and psychomonist ideas. This eventually led to a joint foundation of the Dutch SPR. This alignment between ideological and critical-scientific spiritualists would not last; opinions on how to handle the research subjects (i.e. mediums remained too distinct.

  15. Psychic and somatic anxiety symptoms as predictors of response to fluoxetine in major depressive disorder.

    Science.gov (United States)

    Papakostas, George I; McGrath, Patrick; Stewart, Jonathan; Charles, Dana; Chen, Ying; Mischoulon, David; Dording, Christina; Fava, Maurizio

    2008-10-30

    The purpose of this study was to examine whether the presence/severity of psychic and somatic anxiety symptoms predicted clinical response following a 12-week, flexible-dose (20-60 mg daily), open-label trial of fluoxetine for major depressive disorder (MDD). The presence and severity of psychic and somatic anxiety symptoms were assessed with the use of select subscales of the Symptom Questionnaire and the Hopkins Symptom Checklist among 518 outpatients with MDD. With the use of separate logistic regressions, we tested for the relationship between clinical response, baseline Hamilton Depression Rating Scale (HAM-D-17) scores, and subscale scores at baseline entered separately as independent variables Overall completion, response and remission rates for the trial were 64.2%, 55.4%, and 48.9%, respectively. All subscale scores selected for this analysis significantly predicted treatment response to fluoxetine. The presence/severity of psychic and somatic anxiety symptoms of MDD at baseline predicted an increased likelihood of non-response to fluoxetine in MDD. Studies examining whether specific treatment strategies are more effective than the selective serotonin reuptake inhibitors for MDD patients with high levels of co-morbid psychic and somatic anxiety symptoms are warranted.

  16. Psychic blindness or visual agnosia: early descriptions of a nervous disorder.

    Science.gov (United States)

    Baumann, Christian

    2011-01-01

    This article briefly reports on three early contributions to the understanding of visual agnosia as a syndrome sui generis. The authors of the respective papers worked in different fields such as physiology, ophthalmology, and neurology, and, although they were not in direct contact with each other, their results converged upon a consistent view of a nervous disorder that they called psychic blindness.

  17. Risks and psychic costs of alternative energy sources for generating electricity

    Energy Technology Data Exchange (ETDEWEB)

    Spangler, M.B.

    1981-01-01

    Divisive personal issues will continue to impede the formulation of a coherent national energy policy until we come to grips with the disagreements and anxieties behind the issues. Variations in individual anxiety profiles and limited knowledge are the major sources of conflict. A structured approach for analyzing psychic costs in the risk-cost-benefit analyses of energy options focuses on the electric-utility industry. Coupling psychic costs with economic costs requires an understanding of how social values interact to produce either risk acceptance or risk rejection. A review of the literature shows that people experiencing a continuous anxiety state may come to value the focus of their fear as a policy issue more than on loss of life. Public reaction after the Three Mile Island accident illustrates this condition. Personal bias in risk perception is variable partly because of differences in information. Information and personal values, however, can be mutually incompatible and lead to psychic conflicts. Proponents of soft energy technology, for example, are criticized for their lack of information about the associated risks and not credited for the psychic benefits of their goals. 58 references. (DCK)

  18. Paranormal psychic believers and skeptics: a large-scale test of the cognitive differences hypothesis.

    Science.gov (United States)

    Gray, Stephen J; Gallo, David A

    2016-02-01

    Belief in paranormal psychic phenomena is widespread in the United States, with over a third of the population believing in extrasensory perception (ESP). Why do some people believe, while others are skeptical? According to the cognitive differences hypothesis, individual differences in the way people process information about the world can contribute to the creation of psychic beliefs, such as differences in memory accuracy (e.g., selectively remembering a fortune teller's correct predictions) or analytical thinking (e.g., relying on intuition rather than scrutinizing evidence). While this hypothesis is prevalent in the literature, few have attempted to empirically test it. Here, we provided the most comprehensive test of the cognitive differences hypothesis to date. In 3 studies, we used online screening to recruit groups of strong believers and strong skeptics, matched on key demographics (age, sex, and years of education). These groups were then tested in laboratory and online settings using multiple cognitive tasks and other measures. Our cognitive testing showed that there were no consistent group differences on tasks of episodic memory distortion, autobiographical memory distortion, or working memory capacity, but skeptics consistently outperformed believers on several tasks tapping analytical or logical thinking as well as vocabulary. These findings demonstrate cognitive similarities and differences between these groups and suggest that differences in analytical thinking and conceptual knowledge might contribute to the development of psychic beliefs. We also found that psychic belief was associated with greater life satisfaction, demonstrating benefits associated with psychic beliefs and highlighting the role of both cognitive and noncognitive factors in understanding these individual differences.

  19. Pooled analysis of venlafaxine XR efficacy on somatic and psychic symptoms of anxiety in patients with generalized anxiety disorder.

    Science.gov (United States)

    Meoni, Paolo; Hackett, David; Lader, Malcolm

    2004-01-01

    We evaluated the relative efficacy of venlafaxine XR on the psychic versus somatic symptoms of anxiety in patients with generalized anxiety disorder as determined by the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition. Data were pooled and analyzed from 1,841 patients with generalized anxiety disorder who participated in five short-term (8-week) double-blind, multicenter, placebo-controlled studies, two of which had long-term (6-month) extensions. Somatic and psychic anxieties were studied using the Hamilton rating scale for anxiety (HAM-A) factor scores. We examined response rates (> or =50% improvement over baseline severity score) in the overall population and in patients with mainly somatic symptomatology at baseline (somatizers). Venlafaxine XR significantly reduced factor scores for both psychic and somatic HAM-A factors compared with placebo, from the first and second weeks of treatment, respectively. Patients treated with venlafaxine XR had significantly higher rates of response than patients receiving placebo on the psychic (58% vs. 38%, Ppsychic anxiety response rates, whereas placebo-treated patients showed higher somatic compared with psychic response rates. Somatizers showed similar rates of response to the total population for the somatic factor of the HAM-A in either treatment group. Patients with generalized anxiety disorder treated with venlafaxine XR showed similar absolute rates of response on somatic and psychic symptoms, but relative to patients treated with placebo, more improvement in psychic than somatic symptoms. Copyright 2004 Wiley-Liss, Inc.

  20. Fabrication and optical properties of type-II InP/InAs nanowire/quantum-dot heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Xin; Zhang, Xia; Li, Junshuai; Wu, Yao; Li, Bang; Ren, Xiaomin [State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing, 100876 (China)

    2016-02-15

    The growth and optical properties of InAs quantum dots on a pure zinc blende InP nanowire are investigated. The quantum dots are formed in Stranski-Krastanov mode and exhibit pure zinc blende crystal structure. A substantial blueshift of the dots peak with a cube-root dependence on the excitation power is observed, suggesting a type-II band alignment. The peak position of dots initially red-shifts and then blue-shifts with increasing temperature, which is attributed to the carrier redistribution among the quantum dots. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. The influence of bio-conjugation on photoluminescence of CdSe/ZnS quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Torchynska, Tetyana V. [ESFM Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional, México, D.F. 07738 (Mexico); Vorobiev, Yuri V. [Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV) Querétaro, Libramiento Norponiente 2000, Fracc. Real de Juriquilla, 76230 Querétaro (Mexico); Makhniy, Victor P. [Yuri Fedkovych Chernivtsi National University, 2 Kotsyubynsky Str., 58012 Chernivtsi (Ukraine); Horley, Paul P., E-mail: paul.horley@cimav.edu.mx [Centro de Investigación en Materiales Avanzados, S.C. (CIMAV), Chihuahua/Monterrey, 120 Avenida Miguel de Cervantes, 31109 Chihuahua (Mexico)

    2014-11-15

    We report a considerable blue shift in the luminescence spectra of CdSe/ZnS quantum dots conjugated to anti-interleukin-10 antibodies. This phenomenon can be explained theoretically by accounting for bio-conjugation as a process causing electrostatic interaction between a quantum dot and an antibody, which reduces effective volume of the dot core. To solve the Schrödinger equation for an exciton confined in the quantum dot, we use mirror boundary conditions that were successfully tested for different geometries of quantum wells.

  2. [Management of workers with psychic disorder in the Salerno Medical Unit].

    Science.gov (United States)

    Crescenzi, F; Scarpati, F; Cannavacciuolo, L; Pellegrino, F

    2012-01-01

    Within our Medical Unit of Competent Doctor, in the last years we have registered growing number of workers with psychic disorders, which affect, to various degrees, their normal working activity. This fact has required from us a thorough re-consideration of the psycho-social risks related to employment in general, but also of other issues such as the topic of third parties' healthcare assistance as well as the type of role that interested operators are supposed to play in managing people affected by this type of risks. The current work shows the outcome of the survey which was conducted, highlighting the main critical aspects which have emerged in managing workers with psychic disorders.

  3. [Investigations of psychic/spiritual phenomena in the nineteenth century: somnambulism and spiritualism, 1811-1860].

    Science.gov (United States)

    Pimentel, Marcelo Gulão; Alberto, Klaus Chaves; Moreira-Almeida, Alexander

    2016-01-01

    In the early nineteenth century, investigations into the nature of psychic/spiritual phenomena, like trances and the supposed acquisition of information unattainable using normal sensory channels, prompted much debate in the scientific arena. This article discusses the main explanations offered by the researchers of psychic phenomena reported between 1811 and 1860, concentrating on the two main movements in the period: magnetic somnambulism and modern spiritualism. While the investigations of these phenomena gave rise to multiple theories, they did not yield any consensus. However, they did have implications for the understanding of the mind and its disorders, especially in the areas of the unconscious and dissociation, constituting an important part of the history of psychology and psychiatry.

  4. Violence against children/adolescents in psychic suffering and nursing care: reflections of social phenomenology.

    Science.gov (United States)

    Freitas, Rodrigo Jácob Moreira de; Moura, Natana Abreu de; Monteiro, Ana Ruth Macêdo

    2016-03-01

    Objective To reflect on violence against children and adolescents in psychic suffering, and nursing care based on social phenomenology. Method Theoretical study based on the conceptions of Alfred Schütz. Results The subject in psychic suffering shows conflicts in family relationships, and is often immersed in a biographical situation that removes their autonomy, contributing violence itself. Violence is a social phenomenon expressed through power relations in the everyday world and, through group relationships, resulting in suffering for the victims. Conclusions Studies performed by Schütz enable a new look for the nursing care/health professionals who deal with this problem by allowing them to know the biographical situation, and have full stock of knowledge about their patients, their motivations and the meanings these patients attribute to their experiences. This enables the overcoming of the biomedical model and leads to valuing interpersonal relations from the perspective of a culture of peace.

  5. Visual Hypo and Hypergnosia as Exemplars of Poles of Psychic Tonus in the Occipital Lobes: Multiple Case Analyses

    OpenAIRE

    Braun, Claude M. J.; Guimond, Anik

    2008-01-01

    The “psychic tonus” model or PTM [1] of hemispheric specialization states that the left hemisphere is a psychic and behavioral activator and that the right hemisphere is an inhibitor. The PTM predicts that the tonus of visual representation ought to manifest hemispheric specialization in the occipital lobes. Specifically PTM predicts that pathological positive visual tonus (visual hallucination) ought to be associated more frequently with right occipital lesions. PTM also predicts that pathol...

  6. Restoring psychic containers of identity after a suicide attempt in adolescence.

    Science.gov (United States)

    de Kernier, Nathalie; Marty, François; Devouche, Emmanuel

    2012-01-01

    Suicidal acts during adolescence reveal narcissistic vulnerabilities. The author's observation concerns the quality of ego boundaries, as well as their evolution. Longitudinal studies were conducted on the basis of interviews and projective tests performed within 15 days after the suicide attempt and once again the following year. The quantitative analyses of Fisher and Cleveland's Barrier/Penetration scores on the Rorschach show the evolution of identity mechanisms. The results underscore the importance of restoring psychic containers of identity.

  7. Code Blue: The Blues as Medicine.

    Science.gov (United States)

    Purdy, W. Randolph

    1994-01-01

    Explores the basic features and background of "the blues" as a musical tool, or archetype, for understanding the universal condition of human suffering, for confronting diseases of disability and separation, and for coping or adapting to such suffering. Offers the blues as a method for looking at the spirit of human tragedy and…

  8. [Is the brain the creator of psychic phenomena or is a paradigm shift inevitable?].

    Science.gov (United States)

    Bonilla, Ernesto

    2014-06-01

    Every day new scientific information is appearing that cannot be explained using the classical Newtonian model and is calling for the emergence of a new paradigm that would include the explanation of such phenomena as telepathy, clairvoyance, presentiment, precognition, out of the body experiences, psychic healing, after-death communication, near-death experiences and reincarnation. The materialist paradigm which considers the brain as the sole cause of consciousness and psychic phenomena has been challenged by a new paradigm that seems to demonstrate that there is not a cause-effect relationship between brain activity and psychic phenomena but only a correlation between them, since these phenomena can be experienced without the body and appear to have an extra-cerebral origin (cosmic field, cosmic consciousness?). Of course, the brain is intensely involved in the manifestation of consciousness in our daily life but this is not equivalent to affirm that brain creates consciousness. Recent findings force us to consider a non-physical, spiritual and transpersonal aspect of reality.

  9. PERSONALITY ORIENTED SYSTEM OF STRENGTHENING OF STUDENTS’ PHYSICAL, PSYCHIC AND SOCIAL-MORAL HEALTH

    Directory of Open Access Journals (Sweden)

    Kudryavtsev M.D.

    2016-06-01

    Full Text Available Purpose: to work out content of individualized trainings, permitting to correct deviations in different aspects of physical, psychic and social-moral health of higher educational establishments’ students. Material: in experiment 105 boy students of 20-24 years’ age participated. All students gave conscious consent to participate in experiment. The trainings were practiced 4 times a week, 45 minutes each. Results: it is interesting that change of different personality’s features is rather long process, which in some aspects resist to changes. We showed approaches to training vitally important skills and abilities, required for adaptation to modern social cultural medium; to the simplest techniques of organization of independent health related physical culture trainings; to means of health strengthening, formation of knowledge on health related physical culture. We developed personality-oriented system of formation of psychic and social-moral health. Conclusions: the worked out approach permits to achieve real positive psychic and socially important qualities of student’s personality during one academic year.

  10. Disintegration of the self and the regeneration of 'psychic skin' in the treatment of traumatized refugees.

    Science.gov (United States)

    Luci, Monica

    2017-04-01

    This paper presents a tentative understanding of the characteristics of the extreme traumas, elsewhere called 'complex PTSD', that some refugees and asylum-seekers bring into therapy. It suggests that these kinds of traumas suffered during adulthood may involve a disintegration of the self and a loss of 'psychic skin'. This conceptualization is derived from the treatment of a refugee who survived multiple extreme traumas and with whom efforts were made in therapy to identify a complex methodology making use of supplementary therapeutic tools in addition to individual psychotherapy. The case demonstrates how the disintegration of self implies not only a deep somato-psychic dissociation, but also a loss of intrapsychic and interpersonal space. In the treatment this was worked through via repetition of the victim-aggressor dynamics at multiple levels. In the end, the therapeutic context was structured like a set of concentric layers, creating a 'bandage' over the patient's wounds whilst his 'psychic skin' was able to regenerate. The conditions triggered by extreme traumas in refugees challenge some of the cornerstones of individual psychoanalytic technique, as well as the idea that individual therapy may be thought of as existing in an environmental vacuum. © 2017, The Society of Analytical Psychology.

  11. Blue cures blue but be cautious

    Directory of Open Access Journals (Sweden)

    Pranav Sikka

    2011-01-01

    Full Text Available Methemoglobinemia is a disorder characterized by the presence of >1% methemoglobin (metHb in the blood. Spontaneous formation of methemoglobin is normally counteracted by protective enzyme systems, for example, nicotinamide adenine dinucleotide phosphate (NADPH methemoglobin reductase. Methemoglobinemia is treated with supplemental oxygen and methylene blue (1-2 mg/kg administered slow intravenously, which acts by providing an artificial electron acceptor for NADPH methemoglobin reductase. But known or suspected glucose-6-phosphate dehydrogenase (G6PD deficiency is a relative contraindication to the use of methylene blue because G6PD is the key enzyme in the formation of NADPH through pentose phosphate pathway and G6PD-deficient individuals generate insufficient NADPH to efficiently reduce methylene blue to leukomethylene blue, which is necessary for the activation of the NADPH-dependent methemoglobin reductase system. So, we should be careful using methylene blue in methemoglobinemia patient before G6PD levels.

  12. From DOT to Dotty

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    - Module types are interfaces, which can be abstracted. In this talk Martin will present DOT, a particularly simple calculus that can express systems following these principles. DOT has been developed as the foundation of the next version of Scala. He will also report on dotty, a new Scala compiler that implements the constructs of DOT in its core data structures and that uses the lessons learned to drive Scala’s evolution.

  13. [From reflex arc to psychic apparatus: neurology and psychoanalysis around 1900].

    Science.gov (United States)

    Porath, Erik

    2009-03-01

    As a disciple of Ernst Wilhelm von Brücke and Theodor Meynert, Sigmund Freud was familiar with 19th century physiology and neurology. He started his career with laboratory work and began later on, when being a young medic to develop an explicit psychological method for curating hysterics. These cases of hysteria ask riddles to the established medical discourse and practice. Freud's long time unpublished Entwurf einer Psychologie (1895) makes the attempt of a "psychology for the neurologist". He tried to give a sufficient theory of the psychic apparatus on the basis of natural science. At the same time he (together with Josef Breuer) published his Studies on Hysteria, which--in addition to his earlier essay on Aphasia (1891)--argued, that there is no clear cut relation between body and soul. Despite the dubious, non-reductive character of the soma-psyche-relation, Freud gave reason to search for a complex field of interrelations between the physiological and psychological knowledge, beyond the divide of natural sciences and humanities. Not until his groundbreaking Traumdeutung (1900) Freud gave up the claim of reintegrating psychological knowledge into the neuroscientific field for now. But up to his latest work he always adheres to the principal project of unifying the natural and the psychical being of the subject. In the gap between the two spheres, for long occupied by the discursive figure of the 'psycho-physical parallelism', Freud situated the Unconscious. In the passage to a psychoanalytical theory of psychic events Freud took up the model of the reflex arc well known from neurology. The transmission into psychoanalysis complexifies the unilinearity of reflexes, so that the psychic apparatus can be analysed as a cybernetic mechanism 'avant la lettre'. It is interesting enough that inhibition as well as consciousness play a key role in the regulation of the psychic apparatus. In this context Freud stresses the importance of speech and language within the

  14. Comparative efficacy of pregabalin and benzodiazepines in treating the psychic and somatic symptoms of generalized anxiety disorder.

    Science.gov (United States)

    Lydiard, R Bruce; Rickels, Karl; Herman, Barry; Feltner, Douglas E

    2010-03-01

    Prior research suggests that SSRIs may have greater efficacy for psychic compared to somatic anxiety, while benzodiazepines show greater somatic efficacy. The goal of this analysis was to evaluate the efficacy of pregabalin (PGB) in treating psychic and somatic symptoms of anxiety. Data were combined from six short-term, double-blind, placebo-controlled, fixed-dose trials of PGB in patients with generalized anxiety disorder (GAD). The following PGB daily dose groups were studied: 150 mg (n=210), 300-450 mg (n=455), and 600 mg (n=406), benzodiazepines (6 mg/d lorazepam and 1.5 mg/d alprazolam, n=299), vs. placebo (n=484). Changes in Hamilton Anxiety Rating Scale (HAMA) psychic and somatic anxiety factors and individual items were analysed. Treatment with 300-600 mg PGB significantly improved both the HAMA psychic and somatic anxiety factors. In contrast, treatment with 150 mg PGB appeared to be less effective, achieving significance only on the psychic anxiety factor. PGB (300-450 mg) was associated with significant improvement on 13 out of 14 HAMA items, while treatment with 600 mg PGB was associated with significant improvement in 10 out of 14 HAMA items. Treatment with benzodiazepines was also associated with significant improvement in both psychic and somatic anxiety factors, with significant improvement occurring in 5 out of 14 HAMA items. The results of this pooled analysis indicate that both PGB and benzodiazepines had significant efficacy in treating both HAMA psychic and somatic anxiety. A dose-response effect was evident for PGB that reached a plateau at a dose of 300 mg/d.

  15. Quantum Dots: Theory

    Energy Technology Data Exchange (ETDEWEB)

    Vukmirovic, Nenad; Wang, Lin-Wang

    2009-11-10

    This review covers the description of the methodologies typically used for the calculation of the electronic structure of self-assembled and colloidal quantum dots. These are illustrated by the results of their application to a selected set of physical effects in quantum dots.

  16. Hybrid Double Quantum Dots

    DEFF Research Database (Denmark)

    Sherman, D.; Yodh, J. S.; Albrecht, S. M.

    2016-01-01

    Epitaxial semiconductor-superconductor hybrid materials are an excellent basis for studying mesoscopic and topological superconductivity, as the semiconductor inherits a hard superconducting gap while retaining tunable carrier density. Here, we investigate double-quantum-dot devices made from InA...... that the individual dots host weakly hybridized Majorana modes....

  17. Synthesis of quantum dots

    Science.gov (United States)

    McDaniel, Hunter

    2017-10-17

    Common approaches to synthesizing alloyed quantum dots employ high-cost, air-sensitive phosphine complexes as the selenium precursor. Disclosed quantum dot synthesis embodiments avoid these hazardous and air-sensitive selenium precursors. Certain embodiments utilize a combination comprising a thiol and an amine that together reduce and complex the elemental selenium to form a highly reactive selenium precursor at room temperature. The same combination of thiol and amine acts as the reaction solvent, stabilizing ligand, and sulfur source in the synthesis of quantum dot cores. A non-injection approach may also be used. The optical properties of the quantum dots synthesized by this new approach can be finely tuned for a variety of applications by controlling size and/or composition of size and composition. Further, using the same approach, a shell can be grown around a quantum dot core that improves stability, luminescence efficiency, and may reduce toxicity.

  18. The physical and psychical sphere in the context of development of student young people on the stage of teaching in the institute of higher

    Directory of Open Access Journals (Sweden)

    Sobko S.G.

    2010-05-01

    Full Text Available Influence of employments is shown a physical culture and sport on psychical activity of students of the non-special faculties of institutes of higher education. The questions of system resulting bases of integral development of student young people are examined: physical and psychical his spheres. It is certain that psychical activity is depending on to physically-health-improvement. The higher estimations of results of psychical activity are got on five scales of the modified form of questionnaire of FPI for the students of groups of sporting perfection.

  19. Ratiometric fluorescence detection of mercuric ion based on the nanohybrid of fluorescence carbon dots and quantum dots.

    Science.gov (United States)

    Cao, Benmei; Yuan, Chao; Liu, Bianhua; Jiang, Changlong; Guan, Guijian; Han, Ming-Yong

    2013-07-05

    A novel nanohybrid ratiometric fluorescence probe comprised of carbon dots (C-dots) and hydrophilic CdSe@ZnS quantum dots (QDs) has been developed by simply mixing the blue-emission C-dots with red-emission carboxylmethyldithiocarbamate modified CdSe@ZnS QDs (GDTC-QDs). The nanohybrid ratiometric fluorescence probe exhibits dual emissions at 436 nm and 629 nm under a single excitation wavelength. Due to the strong chelating ability of GDTC on the surface of QDs to mercuric ion (Hg(2+)), the fluorescence of the GDTC-QDs in the nanohybrid system could be selectively quenched in the presence of Hg(2+) while the fluorescence of the C-dots remained constant, resulting in an obviously distinguishable fluorescence color evolution (from red to blue) of the nanohybrid system. The detection limit of this method was found to be as low as 0.1 μM. Furthermore, the recovery result for Hg(2+) in real samples including tap water and lake water by this method was satisfying, suggesting its potential application for Hg(2+) sensing. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. [Treatment of psychic symptoms of a cancer patient in a palliative care].

    Science.gov (United States)

    Idman, Irja

    2013-01-01

    Approximately a third of cancer patients suffer from psychic symptoms recognizable by tested indicators during their illness. The most typical symptom picture is a mixed one consisting of anxiety and depression associated with changes in activity level (fatigue, over-alertness) and sleeping disturbances. According to a recent meta-analysis, some mood disorder fulfilling the DSM or ICD criteria can be diagnosed in approx. 30 to 40% of hospitalized cancer patients. The interpretation as mood disorder included all diagnoses of depression, anxiety disorders as well as mood problems of the adjustment disorder level.

  1. Rhizopus stolonifer mediated biosynthesis of biocompatible cadmium chalcogenide quantum dots.

    Science.gov (United States)

    Mareeswari, P; Brijitta, J; Harikrishna Etti, S; Meganathan, C; Kaliaraj, Gobi Saravanan

    2016-12-01

    We report an efficient method to biosynthesize biocompatible cadmium telluride and cadmium sulphide quantum dots from the fungus Rhizopus stolonifer. The suspension of the quantum dots exhibited purple and greenish-blue luminescence respectively upon UV light illumination. Photoluminescence spectroscopy, X-ray diffraction, and transmission electron microscopy confirms the formation of the quantum dots. From the photoluminescence spectrum the emission maxima is found to be 424 and 476nm respectively. The X-ray diffraction of the quantum dots matches with results reported in literature. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay for cell viability evaluation carried out on 3-days transfer, inoculum 3×10(5) cells, embryonic fibroblast cells lines shows that more than 80% of the cells are viable even after 48h, indicating the biocompatible nature of the quantum dots. A good contrast in imaging has been obtained upon incorporating the quantum dots in human breast adenocarcinoma Michigan Cancer Foundation-7 cell lines. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. GENDER PARTICULAR FEATURES OF PSYCHIC STATE OF ALARMNESS OF ADOPTED CHILDREN FROM NEI «CHILDREN’S VILLAGE-SOS»

    Directory of Open Access Journals (Sweden)

    С. П. Иванова

    2014-01-01

    Full Text Available Purpose – to discover gender particular features of psy-chic state of alarmness of adopted children from «Childrens’ village-SOS».Methodology – empirical research of gender particular features of psychic state of alarmness of adopted children with the help of testing.Results – girls’ level of psychic state of alarmness has more high level in comparison with boys from «Children’s village-SOS». It reflects their fears of self-manifestation and of problems and interaction with teachers.Practical implications – information for «mothers», tea-chers and governesses, working in Children’s villages-SOS about particular features of psychological state of alarmness of the adopted children; development of correctional programs, helping to adapt under new living conditions.Purchase on Elibrary.ru > Buy now

  3. [Aspects of aetiology of neuro-psychic disorders in male liquidators of Chernobyl nuclear power accident consequences].

    Science.gov (United States)

    Skavysh, V A

    2009-01-01

    The author considered aetiology of neuro-psychic disorders in liquidators of Chernobyl nuclear power accident consequences, demonstrated scientific value of studying the liquidators cohort, as they were protected from internal radiation factors and reside on radiation "pure" territories. External radiation doses in those liquidators vary from 16 cGy to 18.7 +/- 10.8 cGy, according to the author. Catamnesis enabled to doubt radiation aetiology of psychic organic syndrome revealed in 1991-1994 by clinical and instrumental studies among 53.6% of 213 male examinees. According to the author, prolonged over 1-2 months external radiation of low dose could not cause health deterioration in adult males. Diagnosed psychic organic syndrome and vascular encephalopathy in some cases could have alcohol aetiology. This conclusion is not extrapolated to the whole liquidators cohort.

  4. Prussian Blue acts as a mediator in a reagentless cytokinin biosensor

    Energy Technology Data Exchange (ETDEWEB)

    Kowalska, Marta, E-mail: marta.kowalska@email.cz [Centre of the Region Hana for Biotechnological and Agricultural Research, Slechtitelu 813/21, 783 71 Olomouc (Czech Republic); Tian Faming [School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom); Smehilova, Maria; Galuszka, Petr; Frebort, Ivo [Centre of the Region Hana for Biotechnological and Agricultural Research, Slechtitelu 813/21, 783 71 Olomouc (Czech Republic); Napier, Richard; Dale, Nicholas [School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom)

    2011-09-09

    Highlights: {center_dot} An electrochemical biosensor for detection of the plant hormone cytokinin. {center_dot} Constitutive expression system for large-scale protein production. {center_dot} CKX enzyme entrapment in sol-gel film on the surface of a PrB-modified electrode. {center_dot} Prussian Blue as an electron mediator between the enzyme and the electrode. {center_dot} The biosensor was sensitive to micromolar concentrations of several cytokinins. - Abstract: An electrochemical biosensor for detection of the plant hormone cytokinin is introduced. Cytokinin homeostasis in tissues of many lower and higher plants is controlled largely by the activity of cytokinin dehydrogenase (CKX, EC 1.5.99.12) that catalyzes an irreversible cleavage of N{sup 6}-side chain of cytokinins. Expression of Arabidopsis thaliana CKX2 from Pichia pastoris was used to prepare purified AtCKX2 as the basis of the cytokinin biosensor. Prussian Blue (PrB) was electrodeposited on Pt microelectrodes prior to deposition of the enzyme in a sol-gel matrix. The biosensor gave amperometric responses to several cytokinins. These responses depended on the presence of both the enzyme and the Prussian Blue. Thus Prussian Blue must act as an electron mediator between the FAD centre in CKX2 and the Pt surface.

  5. Highly Efficient Perovskite-Quantum-Dot Light-Emitting Diodes by Surface Engineering

    KAUST Repository

    Pan, Jun

    2016-08-16

    A two-step ligand-exchange strategy is developed, in which the long-carbon-chain ligands on all-inorganic perovskite (CsPbX3, X = Br, Cl) quantum dots (QDs) are replaced with halide-ion-pair ligands. Green and blue light-emitting diodes made from the halide-ion-paircapped quantum dots exhibit high external quantum efficiencies compared with the untreated QDs.

  6. Two optically active molybdenum disulfide quantum dots as tetracycline sensors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhuosen; Lin, Jintai [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Gao, Jinwei [Institute for Advanced Materials, Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006 (China); Wang, Qianming, E-mail: qmwang@scnu.edu.cn [Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Guangzhou Key Laboratory of Materials for Energy Conversion and Storage, 510006 (China)

    2016-08-01

    In this work, we use the hydrothermal method to develop two luminescent MoS{sub 2} quantum dots (QDs) from L-cysteine and glutathione as sulfur precursors. The special blue emissions give rise to an instantaneous determination of tetracycline (TC) through the quenching of its luminescence. The accessibility of the optical materials and recognition mechanism have been extensively studied. This strategy demonstrated that MoS{sub 2} could act as a new platform for anchoring bioactive species or particular functional moieties. - Highlights: • MoS{sub 2} nanostructures with water solubility have been fabricated. • Blue emission has been achieved. • It displays selective detection to tetracyclines in water.

  7. From catalepsy to psychical research: The itinerary of Timothée Puel (1812-1890).

    Science.gov (United States)

    Evrard, Renaud; Pratte, Erika Annabelle

    2017-02-01

    The physician and botanist Timothée Puel (1812-1890) lived through a pivotal period of psychology (1848-1878), between the academic prohibition of the study of animal magnetism to its disjointed recovery in hypnotism and psychical research. One of his cases of "catalepsy complicated with somnambulism" triggered a lively debate on "extraordinary neuroses" within the young Société médico-psychologique [Medico-psychological Society]. In 1874, Puel founded the Revue de psychologie expérimentale [Journal of Experimental Psychology], the first of its kind in French, which he intended as the vehicle of international interest in psychical research, the scholarly and institutionalized study of "psychism" that prepared the way for the recognition of academic psychology. Puel circulated between these different currents by taking advantage of the polysemy of concepts like "sleep," "experimental psychology," and "psychism." This article discusses his role in the context of emerging French psychology in the mid- to late 19th century. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. [The role of CC-chemokine ligand 2 in the development of psychic dependence on methamphetamine].

    Science.gov (United States)

    Saika, Fumihiro; Kiguchi, Norikazu; Kishioka, Shiroh

    2015-10-01

    Addiction is described as a chronic neurological disorder associated with plasticity in the mesolimbic system. Recently, it has been suggested that neuroinflammation plays an important role in the induction of neuronal plasticity and the formation of pathogenesis in chronic neurological disorders. Therefore, we examined the role of CC-chemokine ligand 2 (CCL2), a proinflammatory chemokine, in the development of psychic dependence on methamphetamine. In mice treated with methamphetamine, CCL2 mRNA was significantly increased in prefrontal cortex and nucleus accumbens. Moreover, phosphorylated tyrosine hydroxylase serine40 (pTH Ser40) levels in the ventral tegmental area (VTA) were increased by methamphetamine. Similarly, pTH Ser40 levels in the VTA were also increased by the intracerebroventricular administration of recombinant CCL2. The increment of pTH Ser40 levels in the VTA by methamphetamine was attenuated by RS504393, a selective CC-chemokine receptor 2 (CCR2) antagonist, indicating that the increased CCL2 activates the brain reward system via CCR2 activation. In the conditioned place preference test, methamphetamine produced place preference in a dose-dependent manner, which was attenuated by RS504393. These results suggest that the activation of the brain reward system via CCL2-CCR2 pathway plays an important role in the development of psychic dependence on methamphetamine.

  9. Nonlocality and exceptional experiences: a study of genius, religious epiphany, and the psychic.

    Science.gov (United States)

    Schwartz, Stephan A

    2010-01-01

    Two hundred years of reductive materialism has failed to explain the extraordinary experiences we know as moments of genius, religious epiphany, and psychic insight. This paper proposes that these three experiences are in essence the same experience, differentiated only by intention and context. It reaches this conclusion based on well-conducted experimental research across the continuum of science--work that proposes a new interdependent model of consciousness that takes into consideration a nonlocal linkage or entanglement, as an aspect of consciousness not limited by space and time. The paper surveys some of the most important relevant research from quantum biology, physics, psychology, medicine, anthropology, and parapsychology. It proposes that more attention should be paid to the autobiographies, correspondence, and journals of men and women to whom history unequivocally accords the designation of genius, saint, or psychic, offering examples from these sources. And it presents comparisons between ethnohistorical material and spiritual traditions, suggesting they arrive at a similar worldview. Finally, it proposes that meditation research, some examples of which are cited, be seen in the context of psychophysical self-regulation, and that it offers one powerful avenue for producing these exceptional experiences. 2010 Elsevier Inc. All rights reserved.

  10. Verdi's Rigoletto: the dialectic interplay of the psychic positions in seemingly 'mindless' violence.

    Science.gov (United States)

    Bergstein, Moshe

    2003-10-01

    In this paper the author demonstrates the interplay of the psychic positions (paranoid-schizoid and depressive, alongside more primitive mental states) as they may appear in experiences of overwhelming anxieties relating to fragmentation and disintegration. These are examined in relation to the appearance of what has been described in the literature as 'mindless' violence. The vehicle for this demonstration is Verdi's opera Rigoletto, which the author examines using Fonagy and Target's model for the understanding of mindless violence. The opera is 'read' as a case study of the protagonist, using the drama as a reflection of Rigoletto's internal object representations. The author attempts to extend Fonagy and Target's model to include primitive mental states, in order to understand 'mindless' violence as a result of collapse of the dialectical relationship of the psychic positions, leading to the violent act as a desperate attempt at re-establishing a sense of self. From this perspective, the moment of the violent act may be seen as use of an autistic object and as supplying of autistic shape. The violence is ultimately directed against the already fragmenting self, especially cherished parts of it, however it may enable acknowledgement of repudiated, unmentalised emotions previously experienced as a void.

  11. Funciones psíquicas de las marcas corporales. // Psychic functions of body marking.

    Directory of Open Access Journals (Sweden)

    Margarita María Valencia Valencia.

    2010-06-01

    Full Text Available This article shows the results of a research titled Funciones psíquicas de las marcas corporales (Psychic Functions of Body Marking that analyses the tattoo, scarification and piercing boom in teenagers and young people. Its aim is to elucidate the body statute in our days. From the acknowledgment of the changes in status of human body throughout history and in different cultures, we investigate the special psychic functions of those practices and their symbolic implications, by using some psychoanalytical theories about body image and adolescence. // Este artículo presenta los resultados de la investigación Funciones psíquicas de las marcas corporales, que interroga el significado del auge de tatuajes, escarificaciones y piercings en adolescentes y jóvenes, con el fin de esclarecer el estatuto del cuerpo en la contemporaneidad. A partir de un reconocimiento de los cambios de estatus que el cuerpo ha tenido a través de la historia y las culturas, se indaga, con ayuda de las teorizaciones psicoanalíticas sobre lo corporal y la adolescencia, acerca de las funciones psíquicas particulares de dichas prácticas y su alcance simbolizador.

  12. Psicología y Salud Psíquica Psychology and Psychic Health

    Directory of Open Access Journals (Sweden)

    Juan Diego Lopera Echavarría

    2011-06-01

    Full Text Available Es frecuente utilizar la expresión salud mental en lugar de salud psíquica. Partiendo de una definición del objeto de la psicología como cultura encarnada, en este escrito argumentaremos por qué es preferible utilizar la expresión salud psíquica. Consideramos que psyché es un concepto mucho más amplio que mente, y que abarca las diferentes facetas de la realidad humana. Basándonos en las elaboraciones de Canguilhem sobre lo normal y lo patológico, proponemos un concepto de salud que contempla el despliegue del ser humano, en tanto continuación de las pautas que la vida misma establece en su proceso de evolución.It is common to use the term "mental health" rather than "psychic health". Starting with a definition of the object of psychology as culture incarnate, in this paper we will argue why it is preferable to use the term psychic health. We believe that "psyche" is a much broader concept than mind, covering the different facets of human reality. Based on the working of Canguilhem on the normal and the pathological, we propose a concept of health that includes the deployment of human beings, like a continuation of the patterns that life itself states in its evolution process.

  13. [Harry Potter--the trauma as a drive for psychic development].

    Science.gov (United States)

    Subkowski, Peter

    2004-12-01

    The Harry Potter books are centered around the psychic development of a traumatised young boy starting from his internalised early experience of being loved by his mother to the sudden loss of both of his parents at the anal stage and the later cumulative traumatisation by being negleced and mistreated by his relatives up to the present times. By identifying with his father and other father replacements Harry Potter finally acquires self-assurance and wins new friends. Harry goes through different stages of initiation into the adult world with all its conflicts and rivalries but also friendships. He stands up to his fears and symptoms resulting from his early childhood traumata and thereby helps to encourage readers of all ages to handle their own conflicts. On the oedipal level Harry Potter finally has to deidealize his father and Dumbledore, but also their opponent the dark Lord Voldemort, who thereby becomes more human, understandable and in the long run probably defeatable. The reader can identify himself with Harry and/ or a wide range of other characters. He can recognize his own experiences in life and conflicts in the story and argue internally with the demonstrated conflict solving patterns on different levels. It is the skillfully displayed and logically constructed story of the psychic development of a child that is traumatised at an early age and the possibilities the reader has to identify selectively with the different characters that constitutes the attractiveness of the Harry Potter novels.

  14. Facile synthesis and photoluminescence mechanism of graphene quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ping; Zhou, Ligang; Zhang, Shenli; Pan, Wei, E-mail: sjtushelwill@sjtu.edu.cn; Shen, Wenzhong, E-mail: wzshen@sjtu.edu.cn [Laboratory of Condensed Matter Spectroscopy and Opto-Electronic Physics, and Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Wan, Neng [SEU-FEI Nano Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronics Science and Engineering, Southeast University, Nanjing 210096 (China)

    2014-12-28

    We report a facile hydrothermal synthesis of intrinsic fluorescent graphene quantum dots (GQDs) with two-dimensional morphology. This synthesis uses glucose, concentrate sulfuric acid, and deionized water as reagents. Concentrated sulfuric acid is found to play a key role in controlling the transformation of as-prepared hydrothermal products from amorphous carbon nanodots to well-crystallized GQDs. These GQDs show typical absorption characteristic for graphene, and have nearly excitation-independent ultraviolet and blue intrinsic emissions. Temperature-dependent PL measurements have demonstrated strong electron-electron scattering and electron-phonon interactions, suggesting a similar temperature behavior of GQDs to inorganic semiconductor quantum dots. According to optical studies, the ultraviolet emission is found to originate from the recombination of electron-hole pairs localized in the C=C bonds, while the blue emission is from the electron transition of sp{sup 2} domains.

  15. Quantum dot molecules

    CERN Document Server

    Wu, Jiang

    2014-01-01

    This book reviews recent advances in the exciting and rapidly growing field of quantum dot molecules (QDMs). It offers state-of-the-art coverage of novel techniques and connects fundamental physical properties with device design.

  16. Blue Ocean Thinking

    Science.gov (United States)

    Orem, Donna

    2016-01-01

    This article describes a concept called the "blue ocean thinking strategy," developed by W. Chan Kim and Renée Mauborgne, professors at INSEAD, an international graduate school of business in France. The "blue ocean" thinking strategy considers opportunities to create new markets for services, rather than focusing solely on…

  17. Image enhancement for increased dot-counting efficiency in FISH.

    Science.gov (United States)

    Shah, Shishir

    2007-11-01

    The most commonly used molecular cytogenetic technique is fluorescence in situ hybridization (FISH). It has been widely applied in many areas of diagnosis and research, including pre-natal and post-natal screening of chromosomal aberrations, pre-implantation genetic diagnosis, cancer cytogenetics, gene mapping, molecular pathology and developmental molecular biology. The analysis of FISH images consists of detecting fluorescent dots, after which the number of dots per cell can be counted or their relative positions can be measured. A major impediment in the analysis of FISH specimens is signal (dot) quality, which is influenced by the hybridization efficiency and/or the sensitivity of the camera that records the images. In this paper, we present an approach to improve the efficiency of detecting fluorescent signals in FISH images by recovering the radiance map of the camera. This allows us to generate a high-dynamic-range image wherein an extended range of the sample radiance captured by the camera can be visualized at distinct intensity values. The resulting higher-order numeric complexity of the transformed image is adjusted (or simplified) by examining the intensity distribution in each of the three colour channels (red, green and blue), and remapping the intensity values to generate a high-contrast image with a lower-order (compressed) dynamic range. The remapping is based on a criterion that optimizes the detection of the hybridized signals, allowing attenuation of saturated intensity values while amplifying low-intensity signals. A simple dot-counting algorithm is used to automatically process 2000 FISH images. The images are taken for lymphocytes from cultured blood specimens for cytogenetic testing. Images are manually analyzed by an expert to obtain ground truth for dot counts. A quantitative analysis is performed by comparing results of automated dot detection on images before and after enhancement with the developed algorithms. In addition, common errors

  18. Graphene quantum dots

    CERN Document Server

    Güçlü, Alev Devrim; Korkusinski, Marek; Hawrylak, Pawel

    2014-01-01

    This book reflects the current status of theoretical and experimental research of graphene based nanostructures, in particular quantum dots, at a level accessible to young researchers, graduate students, experimentalists and theorists. It presents the current state of research of graphene quantum dots, a single or few monolayer thick islands of graphene. It introduces the reader to the electronic and optical properties of graphite, intercalated graphite and graphene, including Dirac fermions, Berry's phase associated with sublattices and valley degeneracy, covers single particle properties of

  19. Synthesis, characterization and cells and tissues imaging of carbon quantum dots

    Science.gov (United States)

    Wang, Jing; Li, Qilong; Zhou, JingE.; Wang, Yiting; Yu, Lei; Peng, Hui; Zhu, Jianzhong

    2017-10-01

    Compare to other quantum dots, carbon quantum dots have its own incomparable advantages, such as low cell toxicity, favorable biocompatibility, cheap production cost, mild reaction conditions, easy to large-scale synthesis and functionalization. In this thesis, we took citric acid monohydrate and diethylene glycol bis (3-aMinopropyl) ether as materials, used decomposition method to acquire carbon quantum dots (CQDs) which can emission blue fluorescence under ultraviolet excitation. In the aspect of application, we achieved the biological imaging of CQDs in vivo and in vitro.

  20. Tuning the photoluminescence of graphene quantum dots by co-doping of nitrogen and sulfur

    Science.gov (United States)

    Luo, Yi; Li, Ming; Sun, Lang; Xu, Yongjie; Hu, Guanghui; Tang, Tao; Wen, Jianfeng; Li, Xinyu

    2017-11-01

    Nitrogen and sulfur co-doped graphene quantum dots (NS-GQDs) were successfully synthesized using a facile, inexpensive, and environmentally friendly hydrothermal reaction of aqueous ammonia, S powder, and graphene quantum dots. The NS-GQDs with oxygen-rich functional groups have a high quantum yield of 41% and a diameter of 1-5 nm. The photoluminescence (PL) properties of the nitrogen-doped graphene quantum dots (N-GQDs) and NS-GQD were investigated. The results showed that the PL emission of the NS-GQD exhibits a clear blue shift of 54 nm compared to that of the N-GQDs.

  1. Temperature dependence of the photoluminescence of MnS/ZnS core—shell quantum dots

    Science.gov (United States)

    Fang, Dai-Feng; Ding, Xing; Dai, Ru-Cheng; Zhao, Zhi; Wang, Zhong-Ping; Zhang, Zeng-Ming

    2014-12-01

    The temperature dependence of the photoluminescence (PL) from MnS/ZnS core—shell quantum dots is investigated in a temperature range of 8 K-300 K. The orange emission from the 4T1 → 6A1 transition of Mn2+ ions and the blue emission related to the trapped surface state are observed in the MnS/ZnS core—shell quantum dots. As the temperature increases, the orange emission is shifted toward a shorter wavelength while the blue emission is shifted towards the longer wavelength. Both the orange and blue emissions reduce their intensities with the increase of temperature but the blue emission is quenched faster. The temperature-dependent luminescence intensities of the two emissions are well explained by the thermal quenching theory.

  2. Carbon quantum dots shuttle electrons to the anode of a microbial fuel cell.

    Science.gov (United States)

    Vishwanathan, A S; Aiyer, Kartik S; Chunduri, L A A; Venkataramaniah, K; Siva Sankara Sai, S; Rao, Govind

    2016-12-01

    Electrodes based on graphite, graphene, and carbon nanomaterials have been used in the anode chamber of microbial fuel cells (MFCs). Carbon quantum dots (C-dots) are a class of versatile nanomaterials hitherto not reported in MFCs. C-dots previously synthesized from coconut husk were reported to possess hydroxyl and carboxyl functional groups on their surface. The presence of these functional groups on a carbon matrix conferred on the C-dots the ability to conduct and transfer electrons. Formation of silver nanoparticles from silver nitrate upon addition of C-dots confirmed their reducing ability. DREAM assay using a mixed microbial culture containing C-dots showed a 172% increase in electron transfer activity and thus confirmed the involvement of C-dots in supplementing redox activity of a microbial culture. Addition of C-dots as a suspension in the anode chamber of an MFC resulted in a 22.5% enhancement in maximum power density. C-dots showed better performance as electron shuttles than methylene blue, a conventional electron shuttle used in MFCs.

  3. Blue ocean strategy.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2004-10-01

    Despite a long-term decline in the circus industry, Cirque du Soleil profitably increased revenue 22-fold over the last ten years by reinventing the circus. Rather than competing within the confines of the existing industry or trying to steal customers from rivals, Cirque developed uncontested market space that made the competition irrelevant. Cirque created what the authors call a blue ocean, a previously unknown market space. In blue oceans, demand is created rather than fought over. There is ample opportunity for growth that is both profitable and rapid. In red oceans--that is, in all the industries already existing--companies compete by grabbing for a greater share of limited demand. As the market space gets more crowded, prospects for profits and growth decline. Products turn into commodities, and increasing competition turns the water bloody. There are two ways to create blue oceans. One is to launch completely new industries, as eBay did with online auctions. But it's much more common for a blue ocean to be created from within a red ocean when a company expands the boundaries of an existing industry. In studying more than 150 blue ocean creations in over 30 industries, the authors observed that the traditional units of strategic analysis--company and industry--are of limited use in explaining how and why blue oceans are created. The most appropriate unit of analysis is the strategic move, the set of managerial actions and decisions involved in making a major market-creating business offering. Creating blue oceans builds brands. So powerful is blue ocean strategy, in fact, that a blue ocean strategic move can create brand equity that lasts for decades.

  4. Thermodynamically Stable Blue Phases

    Science.gov (United States)

    Castles, F.; Morris, S. M.; Terentjev, E. M.; Coles, H. J.

    2010-04-01

    We show theoretically that flexoelectricity stabilizes blue phases in chiral liquid crystals. Induced internal polarization reduces the elastic energy cost of splay and bend deformations surrounding singular lines in the director field. The energy of regions of double twist is unchanged. This in turn reduces the free energy of the blue phase with respect to that of the chiral nematic phase, leading to stability over a wider temperature range. The theory explains the discovery of large temperature range blue phases in highly flexoelectric “bimesogenic” and “bent-core” materials, and predicts how this range may be increased further.

  5. Ratiometric fluorescent paper sensor utilizing hybrid carbon dots-quantum dots for the visual determination of copper ions.

    Science.gov (United States)

    Wang, Yahui; Zhang, Cheng; Chen, Xiaochun; Yang, Bo; Yang, Liang; Jiang, Changlong; Zhang, Zhongping

    2016-03-21

    A simple and effective ratiometric fluorescence nanosensor for the selective detection of Cu(2+) has been developed by covalently connecting the carboxyl-modified red fluorescent cadmium telluride (CdTe) quantum dots (QDs) to the amino-functionalized blue fluorescent carbon nanodots (CDs). The sensor exhibits the dual-emissions peaked at 437 and 654 nm, under a single excitation wavelength of 340 nm. The red fluorescence can be selectively quenched by Cu(2+), while the blue fluorescence is a internal reference, resulting in a distinguishable fluorescence color change from pink to blue under a UV lamp. The detection limit of this highly sensitive ratiometric probe is as low as 0.36 nM, which is lower than the U.S. Environmental Protection Agency (EPA) defined limit (20 μM). Moreover, a paper-based sensor has been prepared by printing the hybrid carbon dots-quantum dots probe on a microporous membrane, which provides a convenient and simple approach for the visual detection of Cu(2+). Therefore, the as-synthesized probe shows great potential application for the determination of Cu(2+) in real samples.

  6. Transferences of Teacher-Casting and Projections of Redemption: Teacher Education, Young Adult Literature and the Psychic Life of Reading

    Science.gov (United States)

    Lewkowich, David

    2015-01-01

    As the psychic life of reading is imbued with desire, transferences and other forms of emotional turbulence, readers invariably and often unconsciously project their anxieties, hopes and worries onto the lives of fictional characters. Using the lens of psychoanalytic theory, this article explores the meanings produced in the convergence of teacher…

  7. Rethinking White Resistance: Exploring the Discursive Practices and Psychical Negotiations of "Whiteness" in Feminist, Anti-Racist Education

    Science.gov (United States)

    Ringrose, Jessica

    2007-01-01

    This article explores how under-theorized representations of whiteness in pedagogical literatures have informed simplistic ideas about white resistance among students. It is argued that the performance and practice of discourses of whiteness in pedagogical contexts, and the subjective, psychical and emotional complexities of engaging with…

  8. Standardisation vs. adaption : a conjoint experiment on the influence of psychic, cultural and geographical distance on international marketing mix decisions

    NARCIS (Netherlands)

    Kraus, Sascha; Meier, Fabian; Eggers, Felix; Bouncken, Ricarda B.; Schuessler, Felix

    2016-01-01

    This paper delivers new insights into how psychic, cultural and geographical distance influence international marketing mix decisions on the basis of a choice-based conjoint analysis with 96 managers from Switzerland and Liechtenstein. In this experiment, the managers had to decide whether the four

  9. From somatic pain to psychic pain: The body in the psychoanalytic field.

    Science.gov (United States)

    Hartung, Thomas; Steinbrecher, Michael

    2017-03-24

    The integration of psyche and soma begins with a baby's earliest contact with his or her parents. With the help of maternal empathy and reverie, β-elements are transformed into α-elements. While we understand this to be the case, we would like to enquire what actually happens to those parts of the affect which have not been transformed? For the most part they may be dealt with by evacuation, but they can also remain within the body, subsequently contributing to psychosomatic symptoms. This paper describes how the body serves as an intermediate store between the psychic (inner) and outer reality. The authors focuses on the unconscious communicative process between the analyst and the analysand, and in particular on how psychosomatic symptoms can spread to the analyst's body. The latter may become sensitive to the analysand's psychosomatic symptoms in order to better understand the psychoanalytical process. Sensory processes (visual and auditory) and psychic mechanisms such as projective identification can serve as a means for this communication. One of the first analysts to deal with this topic was Wilhelm Reich. He described one kind of psychosomatic defence like a shell, the character armour, comparing the armour formed by muscle tension with another, more psychical type of armour. This concept can be linked to Winnicott's contribution of the false self and later on to Feldman's concept of compliance as a defence. The authors links further details of the clinical material with theoretical concepts from Joyce McDougall, Piera Aulagnier, and Ricardo Rodulfo and Marilia Aisenstein. With the aid of the complex concept of projective identification, as described by Heinz Weiss, the authors discusses the important question of how the analyst gets in touch with the patient's current psychosomatic state, and describes a specific communication between the body of the psychoanalyst and the body of the patient. A vignette illustrates in greater detail the relationship

  10. [Clinical and pathogenetic relationships between immuno-inflammatory rheumatic diseases and psychic disorders].

    Science.gov (United States)

    Lisitsina, T A; Vel'tishchev, D Iu; Krasnov, V N; Nasonov, E L

    2014-01-01

    Literature data and original observations have been used to develop the rationale for the necessity of studying psychic disorders (PD) in patients with immuno-inflammatory rheumatic diseases (RD), such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Special attention is given to the high frequency of disturbances of the anxiety and depression profile (DADP) in patients having RA and SLE with reference to the common provoking stress and pathogenic factors, clinical manifestations, and RD. Great importance is attributed to the degree of depression associated with inflammatory activity, pain intensity, fatigue, sleep disorders, severe functional insufficiency and low quality of life in the patients with RA and SLE. Special emphasis is laid on the influence of depression and stress factors on the survival and morality of patients with these pathologies, the necessity of their combined treatment with the participation of rheumatologists, psychiatrists and medical psychologists for the improvement of clinical course and prognosis of RD.

  11. [Analysis of the prevalence of psychic disorders in the metropolitan region of Recife].

    Science.gov (United States)

    Paixão, Cíntia; Matias, Daniele; Alencar, Izabel; Nunes, Marina; Sales, Patrícia; Veiga, Paulo Henrique Altran

    2009-01-01

    Mental health is a state of well-being, in which the individual is aware of its capacities, capable of coping with the ordinary stress of everyday life, of working productively and of functioning in society. The purpose of the present work is a quantitative analysis of the prevalence of psychic disorders, using references such as sex, age, kind of disorder and care delivered to the carriers. Social assistants of three psychiatric hospitals of the Metropolitan Region of Recife - the Psychiatric Hospital Ulysses Pernambucano, the Nucleus for Psychosocial Care of Pernambuco (NAPPE) and the Hospital Colony Alcides Codeceira - answered an adapted version of the Self Reporting Questionnaire (SRQ-20). The results showed a higher incidence of disorders in women in the age group between 41 and 60 years. Schizophrenia was the most frequently observed kind of mental disorder. Among the different treatments offered were drug therapy and individual and group therapy, the latter showing better results.

  12. Does a previous surgical experience interfere on psychic stress in patients submitted to major surgery?

    Science.gov (United States)

    Alberti, Luiz Ronaldo; Daian, Márcia Rodrigues; Petroianu, Andy

    2014-01-01

    to evaluate the impact of stress in patients undergoing major surgeries under general anesthesia, relating their physical and psychic reactions to the different stages of stress. we studied 100 adult patients of both genders, who were divided into two groups: Group 1 - 22 patients without experience with surgery; Group 2 - 78 patients previously submitted to medium and major surgery. To investigate the stress, we used the Inventory of Stress Symptoms for Adults, developed by Lipp, the day before the procedure and two days and seven days after the operation. The comparison of groups with respect to gender, pain, and percentage of stress were performed using the Chi-square test, and for the age variable the Student's t test was used. Differences were considered significant at pdisorders.

  13. Psychical research in the history and philosophy of science. An introduction and review.

    Science.gov (United States)

    Sommer, Andreas

    2014-12-01

    As a prelude to articles published in this special issue, I sketch changing historiographical conventions regarding the 'occult' in recent history of science and medicine scholarship. Next, a review of standard claims regarding psychical research and parapsychology in philosophical discussions of the demarcation problem reveals that these have tended to disregard basic primary sources and instead rely heavily on problematic popular accounts, simplistic notions of scientific practice, and outdated teleological historiographies of progress. I conclude by suggesting that rigorous and sensitively contextualized case studies of past elite heterodox scientists may be potentially useful to enrich historical and philosophical scholarship by highlighting epistemologies that have fallen through the crude meshes of triumphalist and postmodernist historiographical generalizations alike. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Blue Holes & Hurricanes

    National Research Council Canada - National Science Library

    David Levin

    2017-01-01

    A blue hole in the ocean is a striking sight. Fly over remote areas of the Caribbean Sea and you'll see shallow turquoise water stretching for miles, interrupted only by occasional sand bars and coral reefs...

  15. Blue Ribbon Panel Report

    Science.gov (United States)

    An NCI Cancer Currents blog by the NCI acting director thanking the cancer community for contributing to the Cancer Moonshot Blue Ribbon Panel report, which was presented to the National Cancer Advisory Board on September 7.

  16. Blue-Green Algae

    Science.gov (United States)

    ... been used for food for several centuries in Mexico and some African countries. They have been sold ... appear to reduce symptoms such as hot flashes. Obesity. Research on the effects of blue-green algae ...

  17. Methylene blue test

    Science.gov (United States)

    Methemoglobinemia - methylene blue test ... No special preparation is required for this test. ... which are genetic (problem with your genes). This test is used to tell the difference between methemoglobinemia ...

  18. New York Blue

    Data.gov (United States)

    Federal Laboratory Consortium — New York Blue is used cooperatively by the Laboratory and Stony Brook University as part of the New York Center for Computation Sciences. Ranked as the 28th fastest...

  19. Priming psychic and conjuring abilities of a magic demonstration influences event interpretation and random number generation biases

    Directory of Open Access Journals (Sweden)

    Christine eMohr

    2015-01-01

    Full Text Available Magical ideation and belief in the paranormal is considered to represent a trait-like character; people either believe in it or not. Yet, anecdotes indicate that exposure to an anomalous event can turn sceptics into believers. This transformation is likely to be accompanied by altered cognitive functioning such as impaired judgements of event likelihood. Here, we investigated whether the exposure to an anomalous event changes individuals’ explicit traditional (religious and non-traditional (e.g. paranormal beliefs as well as cognitive biases that have previously been associated with non-traditional beliefs, e.g. repetition avoidance when producing random numbers in a mental dice task. In a classroom, 91 students saw a magic demonstration after their psychology lecture. Before the demonstration, half of the students were told that the performance was done respectively by a conjuror (magician group or a psychic (psychic group. The instruction influenced participants’ explanations of the anomalous event. Participants in the magician, as compared to the psychic group, were more likely to explain the event through conjuring abilities while the reverse was true for psychic abilities. Moreover, these explanations correlated positively with their prior traditional and non-traditional beliefs. Finally, we observed that the psychic group showed more repetition avoidance than the magician group, and this effect remained the same regardless of whether assessed before or after the magic demonstration. We conclude that pre-existing beliefs and contextual suggestions both influence people’s interpretations of anomalous events and associated cognitive biases. Beliefs and associated cognitive biases are likely flexible well into adulthood and change with actual life events.

  20. Magneto-optical absorption in semiconducting spherical quantum dots: Influence of the dot-size, confining potential, and magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kushwaha, Manvir S. [Department of Physics and Astronomy, Rice University, P.O. Box 1892, Houston, TX 77251 (United States)

    2014-12-15

    Semiconducting quantum dots – more fancifully dubbed artificial atoms – are quasi-zero dimensional, tiny, man-made systems with charge carriers completely confined in all three dimensions. The scientific quest behind the synthesis of quantum dots is to create and control future electronic and optical nanostructures engineered through tailoring size, shape, and composition. The complete confinement – or the lack of any degree of freedom for the electrons (and/or holes) – in quantum dots limits the exploration of spatially localized elementary excitations such as plasmons to direct rather than reciprocal space. Here we embark on a thorough investigation of the magneto-optical absorption in semiconducting spherical quantum dots characterized by a confining harmonic potential and an applied magnetic field in the symmetric gauge. This is done within the framework of Bohm-Pines’ random-phase approximation that enables us to derive and discuss the full Dyson equation that takes proper account of the Coulomb interactions. As an application of our theoretical strategy, we compute various single-particle and many-particle phenomena such as the Fock-Darwin spectrum; Fermi energy; magneto-optical transitions; probability distribution; and the magneto-optical absorption in the quantum dots. It is observed that the role of an applied magnetic field on the absorption spectrum is comparable to that of a confining potential. Increasing (decreasing) the strength of the magnetic field or the confining potential is found to be analogous to shrinking (expanding) the size of the quantum dots: resulting into a blue (red) shift in the absorption spectrum. The Fermi energy diminishes with both increasing magnetic-field and dot-size; and exhibits saw-tooth-like oscillations at large values of field or dot-size. Unlike laterally confined quantum dots, both (upper and lower) magneto-optical transitions survive even in the extreme instances. However, the intra-Landau level

  1. Magneto-optical absorption in semiconducting spherical quantum dots: Influence of the dot-size, confining potential, and magnetic field

    Directory of Open Access Journals (Sweden)

    Manvir S. Kushwaha

    2014-12-01

    Full Text Available Semiconducting quantum dots – more fancifully dubbed artificial atoms – are quasi-zero dimensional, tiny, man-made systems with charge carriers completely confined in all three dimensions. The scientific quest behind the synthesis of quantum dots is to create and control future electronic and optical nanostructures engineered through tailoring size, shape, and composition. The complete confinement – or the lack of any degree of freedom for the electrons (and/or holes – in quantum dots limits the exploration of spatially localized elementary excitations such as plasmons to direct rather than reciprocal space. Here we embark on a thorough investigation of the magneto-optical absorption in semiconducting spherical quantum dots characterized by a confining harmonic potential and an applied magnetic field in the symmetric gauge. This is done within the framework of Bohm-Pines’ random-phase approximation that enables us to derive and discuss the full Dyson equation that takes proper account of the Coulomb interactions. As an application of our theoretical strategy, we compute various single-particle and many-particle phenomena such as the Fock-Darwin spectrum; Fermi energy; magneto-optical transitions; probability distribution; and the magneto-optical absorption in the quantum dots. It is observed that the role of an applied magnetic field on the absorption spectrum is comparable to that of a confining potential. Increasing (decreasing the strength of the magnetic field or the confining potential is found to be analogous to shrinking (expanding the size of the quantum dots: resulting into a blue (red shift in the absorption spectrum. The Fermi energy diminishes with both increasing magnetic-field and dot-size; and exhibits saw-tooth-like oscillations at large values of field or dot-size. Unlike laterally confined quantum dots, both (upper and lower magneto-optical transitions survive even in the extreme instances. However, the intra

  2. Grow light for plant factory using quantum dot LED

    Directory of Open Access Journals (Sweden)

    Jin-Won Song

    2016-01-01

    Full Text Available The research on the LED base next generation lighting is actively accomplished in the field of lighting for the energy saving for the global warming prevention. In this study, made the multifunctional LED light source as research on the lighting equipment that using the Quantum Dot. Synthesized the quantum dot having the wavelength of 510nm, 610nm, 660nm and confirmed the possibility of characteristic evaluation result that it was applicable as the result LED fluorescent substance. We synthesized quantum dot that mixed the resin and was spread on the blue LED having the wavelength of 455nm. We make the multi-wavelength LED device in order to confirm the possibility for application for the plant factory and evaluated the electrical characteristic of the LED light source. Also, we evaluated the growth characteristic so that the quantum dot could confirm the possibility for application by plant growth light source. Finally we presented the possibility for application of the quantum dot with the multifunction LED light source.

  3. Double quantum dot memristor

    Science.gov (United States)

    Li, Ying; Holloway, Gregory W.; Benjamin, Simon C.; Briggs, G. Andrew D.; Baugh, Jonathan; Mol, Jan A.

    2017-08-01

    Memristive systems are generalizations of memristors, which are resistors with memory. In this paper, we present a quantum description of quantum dot memristive systems. Using this model we propose and experimentally demonstrate a simple and practical scheme for realizing memristive systems with quantum dots. The approach harnesses a phenomenon that is commonly seen as a bane of nanoelectronics, i.e., switching of a trapped charge in the vicinity of the device. We show that quantum dot memristive systems have hysteresis current-voltage characteristics and quantum jump-induced stochastic behavior. While our experiment requires low temperatures, the same setup could, in principle, be realized with a suitable single-molecule transistor and operated at or near room temperature.

  4. Hexagonal graphene quantum dots

    KAUST Repository

    Ghosh, Sumit

    2016-12-05

    We study hexagonal graphene quantum dots, using density functional theory, to obtain a quantitative description of the electronic properties and their size dependence, considering disk and ring geometries with both armchair and zigzag edges. We show that the electronic properties of quantum dots with armchair edges are more sensitive to structural details than those with zigzag edges. As functions of the inner and outer radii, we find in the case of armchair edges that the size of the band gap follows distinct branches, while in the case of zigzag edges it changes monotonically. This behaviour is further analyzed by studying the ground state wave function and explained in terms of its localisation.

  5. Quantum dot solar cells

    CERN Document Server

    Wu, Jiang

    2013-01-01

    The third generation of solar cells includes those based on semiconductor quantum dots. This sophisticated technology applies nanotechnology and quantum mechanics theory to enhance the performance of ordinary solar cells. Although a practical application of quantum dot solar cells has yet to be achieved, a large number of theoretical calculations and experimental studies have confirmed the potential for meeting the requirement for ultra-high conversion efficiency. In this book, high-profile scientists have contributed tutorial chapters that outline the methods used in and the results of variou

  6. Effect of Sb and As spray on emission characteristics of InAs quantum dots with AlAs capping layer

    Science.gov (United States)

    Zhang, Z.; Tan, S.; Kim, Y.; Liu, Z.; Reece, P. J.; Bremner, S. P.

    2017-10-01

    We report on the influence of an Sb/As combined spray on the physical and optical characteristics of AlAs-capped InAs/GaAs quantum dots grown by Molecular Beam Epitaxy. Photoluminescence emission from the quantum dots shows a significant peak position shift under different Sb/As spray sequences. A blue-shifted quantum dot emission peak with an initial Sb rest indicates a large-to-small quantum dots transition process, with a bi-modal quantum dot size distribution inferred. High-resolution Transmission Electron Microscopy results reveal a large density of small quantum dots when the Sb spray is treated first. Furthermore, defect passivation in the vicinity of the quantum dots by use of Sb spray was detected.

  7. Optical and electrochemical applications of silicon-carbon dots/silicon dioxide nanocomposites.

    Science.gov (United States)

    Shih, Chung-Chien; Chen, Po-Cheng; Lin, Guan-Lin; Wang, Chia-Wei; Chang, Huan-Tsung

    2015-01-27

    Various colors of photoluminescent SiC-dots/SiO2 prepared through a simple heating process have been employed for optical and electrochemical applications. Blue (B)-, green (G)-, and tan (T)-SiC-dots/SiO2 powders have been prepared from SiC-dots that had been prepared from 3-aminopropyl trimethoxysilane through a hydrothermal route by simply controlling heating at 60 °C for 60 min and 300 °C for 10 and 20 min, respectively. The B-, G-, and T-SiC-dots/SiO2 nanocomposites emit at 455, 534, and 574 nm, respectively, under excitation at 360 nm. B-, G-, and T-SiC-dots/SiO2 glass films show at least seven colors when excited at 360, 460, and 520 nm. Through a heat-induced photoluminescence (PL) change, a representative lithographic pattern of B-SiC-dots/SiO2 films has been fabricated using a near-infrared laser. The B-, G-, and T-SiC-dots/SiO2 also possess high electrocatalytic activity for the oxygen reduction reaction. Having such interesting PL and electrical properties, the stable, low-toxic, and cost-effective B-, G-, and T-SiC-dots/SiO2 nanocomposites show great economic potential in many applications such as light-emitting diodes, photoluminescent windows, and fuel cells.

  8. Microwave-Assisted Polyol Synthesis of Water Dispersible Red-Emitting Eu3+-Modified Carbon Dots

    Directory of Open Access Journals (Sweden)

    Hailong Dong

    2016-12-01

    Full Text Available Eu3+-modified carbon dots (C-dots, 3–5 nm in diameter, were prepared, functionalized, and stabilized via a one-pot polyol synthesis. The role of Eu2+/Eu3+, the influence of O2 (oxidation and H2O (hydrolysis, as well as the impact of the heating procedure (conventional resistance heating and microwave (MW heating were explored. With the reducing conditions of the polyol at the elevated temperature of synthesis (200–230 °C, first of all, Eu2+ was obtained resulting in the blue emission of the C-dots. Subsequent to O2-driven oxidation, Eu3+-modified, red-emitting C-dots were realized. However, the Eu3+ emission is rapidly quenched by water for C-dots prepared via conventional resistance heating. In contrast to the hydroxyl functionalization of conventionally-heated C-dots, MW-heating results in a carboxylate functionalization of the C-dots. Carboxylate-coordinated Eu3+, however, turned out as highly stable even in water. Based on this fundamental understanding of synthesis and material, in sum, a one-pot polyol approach is established that results in H2O-dispersable C-dots with intense red Eu3+-line-type emission.

  9. Diamond LED substrate and novel quantum dots.

    Science.gov (United States)

    Sung, James C; Sung, Michael

    2009-02-01

    Nitride LED (e.g., GaN) has become the mainstream of blue light source. The blue light can be converted to white light by exciting a phosphor (e.g., Nichia's YAG or Osram's TAG) with the complementary yellow emission. However, GaN is typically deposited on sapphire (Al2O3) substrates formed by crystal pulling or hexagonal (e.g., 4 H or 6 H) SiC wafers condensed from SiC vapor. In either case, the nitride lattice is ridden (e.g., 10(9)/cm2) with dislocations. The high dislocation density with sapphire is due to the large (>13%) lattice mismatch; and with hexagonal SiC, because of intrinsic defects. Cubic (beta) SiC may be deposited epitaxially using a CVD reactor onto silicon wafer by diffusing the interface and by chemical gradation. A reactive echant (e.g., hydrogen or fluorine) can be introduced periodically to gasify mis-aligned atoms. In this case, large single crystal wafers would be available for the manufacture of high bright LED with superb electro-optical efficiency. The SiC wafer may be coated with diamond film that can eliminate heat in real time. As a result of lower temperature, the nitride LED can be brighter and it will last longer. The blue light of GaN LED formed on SiC on Diamond (SiCON) LED may also be scattered by using novel quantum dots (e.g., 33 atom pairs of CdSe) to form a broad yellow light that blend in with the original blue light to form sunlight-like white light. This would be the ideal source for general illumination (e.g., for indoor) or backlighting (e.g., for LCD).

  10. RedDots Replayed

    DEFF Research Database (Denmark)

    Kinnunen, Tomi; Sahidullah, Md; Falcone, Mauro

    2017-01-01

    the protection of text-dependent ASV systems from replay attacks in the face of variable recording and playback conditions. Derived from the re-recording of the original RedDots database, the effort is aligned with that in text-dependent ASV and thus well positioned for future assessments of replay spoofing...

  11. Carbon nanotube quantum dots

    NARCIS (Netherlands)

    Sapmaz, S.

    2006-01-01

    Low temperature electron transport measurements on individual single wall carbon nanotubes are described in this thesis. Carbon nanotubes are small hollow cylinders made entirely out of carbon atoms. At low temperatures (below ~10 K) finite length nanotubes form quantum dots. Because of its small

  12. White dots do matter

    DEFF Research Database (Denmark)

    Soeken, Mathias; Thomsen, Michael Kirkedal

    2013-01-01

    Toffoli circuits. We also show how to use these rules to derive more complex formulas. The major difference compared to existing approaches is the use of negative controls (white dots), which significantly increases the algebraic strength. We show how existing optimisation approaches can be adapted...

  13. Indium Phosphide-Based Quantum Dots with Shell-Enhanced Absorption for Luminescent Down-Conversion.

    Science.gov (United States)

    Dupont, Dorian; Tessier, Mickael D; Smet, Philippe F; Hens, Zeger

    2017-08-01

    It is shown that admixing small amounts of cadmium into the shell of InP/ZnSe core/shell quantum dots results in an increased absorption of blue light and a limited redshift of the band-edge emission. These effects reflect the reduced bandgap of (Zn,Cd)Se alloys and their smaller conduction-band offset with InP. Nevertheless, adjusting the InP core size enables InP/ZnSe and InP/(Zn,Cd)Se quantum dots with identical emission characteristics to be made. Processing both materials into remote phosphor disks, it is demonstrated that the shell-enhanced absorbance of InP/(Zn,Cd)Se has the double benefit of suppressing self-absorption and reducing the amount of quantum dots by weight needed to attain a given blue-to-red color conversion. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Near-infrared fundus autofluorescence in multiple evanescent white-dot syndrome.

    Science.gov (United States)

    Battaglia Parodi, Maurizio; Iacono, Pierluigi; Falcomatà, Bruno; Bolognesi, Gianluigi; Bandello, Francesco

    2015-01-01

    To report the near-infrared fundus autofluorescence (NIR-FAF) pattern in 2 cases of multiple evanescent white-dot syndrome (MEWDS). Three consecutive patients with MEWDS underwent a complete ophthalmologic examination, including color photograph, blue-light fundus autofluorescence, NIR-FAF, fluorescein angiography, and indocyanine green angiography (ICGA). Main outcome measure was the identification of NIR-FAF pattern. Fluorescein angiography showed patchy hyperfluorescence of the whitish dots. Indocyanine green angiography showed hypofluorescent spots throughout the examination. Blue-light fundus autofluorescence disclosed a speckled pattern without extension to the foveal area, whereas NIR-AF showed several hypoautofluorescent lesions involving also the fovea, which corresponded to the whitish dots visible on biomicroscopy and to the hypofluorescent lesions detectable on ICGA. Near-infrared fundus autofluorescence is characterized by hypoautofluorescent spots corresponding to the inflammatory lesions typical of MEWDS and can be considered as a valuable noninvasive technique to diagnose and monitor patients with MEWDS.

  15. A Blue Lagoon Function

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2007-01-01

    We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$.......We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$....

  16. The Blue Collar Brain

    Directory of Open Access Journals (Sweden)

    Guy eVan Orden

    2012-06-01

    Full Text Available Much effort has gone into elucidating control of the body by the brain, less so the role of the body in controlling the brain. This essay develops the idea that the brain does a great deal of work in the service of behavior that is controlled by the body, a blue collar role compared to the white collar control exercised by the body. The argument that supports a blue collar role for the brain is also consistent with recent discoveries clarifying the white collar role of synergies across the body's tensegrity structure, and the evidence of critical phenomena in brain and behavior.

  17. THE SUBJECTIVAL CONTENT OF IMAGES “SUCCESSFUL MAN” AND “SUCCESSFUL WOMAN” AS A FACTOR OF PSYCHIC ADJUSTMENT OF WOMEN IN INVOLUNTARY UNEMPLOYMENT SITUATION

    National Research Council Canada - National Science Library

    Lopukhova Olga Gennadevna; Beglova Elmira Ildusovna

    2013-01-01

    ...” and parameters of psychic and social adjustment of women belonging to different generations. Methodology. Subjective image “successful person” means a stable and possibly gender differentiated element...

  18. THE SUBJECTIVAL CONTENT OF IMAGES “SUCCESSFUL MAN” AND “SUCCESSFUL WOMAN” AS A FACTOR OF PSYCHIC ADJUSTMENT OF WOMEN IN INVOLUNTARY UNEMPLOYMENT SITUATION

    National Research Council Canada - National Science Library

    Ольга Геннадьевна Лопухова; Эльмира Ильдусовна Беглова

    2013-01-01

    ...” and parameters of psychic and social adjustment of women belonging to different generations.Methodology.  Subjective image “successful person” means a stable and possibly gender differentiated element...

  19. Reflections on trauma, symbolization and psychic pain in a case of neurosis and a case of psychosis.

    Science.gov (United States)

    Maldonado, Jorge Luis; Solimano, Alberto Luis

    2016-10-01

    This paper seeks to advance some considerations on trauma, historical reality, its symbolization and the psychic pain generated by the investigation of unconscious processes in psychoanalytic treatment. These themes will be explored by demonstrating the differences arising between traumatic experiences and their expression in phantasy, as they occurred in a case of neurosis and another of psychosis. In each case, the differences in the features of the symbolization and the processes of working through shall also be taken into consideration. Particular attention shall be paid to the specific difficulties encountered by the analyst in the interpretative treatment of the trauma resulting from the amount of psychic pain induced in the patient, which at times proves to be an insurmountable barrier and a destructive distortion of the process. Copyright © 2016 Institute of Psychoanalysis.

  20. Tuning the Photoluminescence of Graphene Quantum Dots by Photochemical Doping with Nitrogen.

    Science.gov (United States)

    Xu, Xiaofen; Gao, Fuhua; Bai, Xiaohua; Liu, Fuchi; Kong, Wenjie; Li, Ming

    2017-11-20

    Nitrogen-doped graphene quantum dots (NGQDs) were synthesized by irradiating graphene quantum dots (GQDs) in an NH₃ atmosphere. The photoluminescence (PL) properties of the GQDs and the NGQDs samples were investigated. Compared with GQDs, a clear PL blue-shift of NGQDs could be achieved by regulating the irradiating time. The NGQDs obtained by irradiation of GQDs for 70 min had a high N content of 15.34 at % and a PL blue-shift of about 47 nm. This may be due to the fact that photochemical doping of GQDs with nitrogen can significantly enhance the contents of pyridine-like nitrogen, and also effectively decrease the contents of oxygen functional groups of NGQDs, thus leading to the observed obvious PL blue-shift.

  1. Tuning the Photoluminescence of Graphene Quantum Dots by Photochemical Doping with Nitrogen

    Directory of Open Access Journals (Sweden)

    Xiaofen Xu

    2017-11-01

    Full Text Available Nitrogen-doped graphene quantum dots (NGQDs were synthesized by irradiating graphene quantum dots (GQDs in an NH3 atmosphere. The photoluminescence (PL properties of the GQDs and the NGQDs samples were investigated. Compared with GQDs, a clear PL blue-shift of NGQDs could be achieved by regulating the irradiating time. The NGQDs obtained by irradiation of GQDs for 70 min had a high N content of 15.34 at % and a PL blue-shift of about 47 nm. This may be due to the fact that photochemical doping of GQDs with nitrogen can significantly enhance the contents of pyridine-like nitrogen, and also effectively decrease the contents of oxygen functional groups of NGQDs, thus leading to the observed obvious PL blue-shift.

  2. [Effect of combined hormonal oral contraception on the somatic and psychic status of women of reproductive age].

    Science.gov (United States)

    Vertkin, A L; Nosova, A V

    2012-01-01

    The paper is devoted to the topical problem of maintaining somatic and psychic health of the women of reproductive age by rational pregnancy planning and prevention of abortions by modern methods of contraception including combined oral hormonal contraception. Unfortunately, this approach is rarely employed in this country (5-6%). Results of retrospective analysis of medical documentation, clinical efficacy and safety of modern combined oral hormonal contraception are presented.

  3. Code blue: seizures.

    Science.gov (United States)

    Hoerth, Matthew T; Drazkowski, Joseph F; Noe, Katherine H; Sirven, Joseph I

    2011-06-01

    Eyewitnesses frequently perceive seizures as life threatening. If an event occurs on the hospital premises, a "code blue" can be called which consumes considerable resources. The purpose of this study was to determine the frequency and characteristics of code blue calls for seizures and seizure mimickers. A retrospective review of a code blue log from 2001 through 2008 identified 50 seizure-like events, representing 5.3% of all codes. Twenty-eight (54%) occurred in inpatients; the other 22 (44%) events involved visitors or employees on the hospital premises. Eighty-six percent of the events were epileptic seizures. Seizure mimickers, particularly psychogenic nonepileptic seizures, were more common in the nonhospitalized group. Only five (17.9%) inpatients had a known diagnosis of epilepsy, compared with 17 (77.3%) of the nonhospitalized patients. This retrospective survey provides insights into how code blues are called on hospitalized versus nonhospitalized patients for seizure-like events. Copyright © 2011. Published by Elsevier Inc.

  4. The Blue Baby Syndrome

    Indian Academy of Sciences (India)

    climate change, water and soil pollution, environ- mental impacts of wastewater irrigation and soil nutrient management. Keywords. Cyanosis, hemoglobin, infants, methemoglobinemia, nitrate. Deepanjan Majumdar. Blue Baby Syndrome or Methemoglobinemia is caused by decreased ability of blood to carry oxygen, ...

  5. Defining the Blue economy

    CSIR Research Space (South Africa)

    Smith-Godfrey, S

    2016-01-01

    Full Text Available MARITIME AFFAIRS: JOURNAL OF THE NATIONAL MARITIME FOUNDATION OF INDIA, 2016 http://dx.doi.org/10.1080/09733159.2016.1175131 Defining the Blue Economy S. Smith-Godfrey Council for Scientific and Industrial Research (CSIR), Pretoria, South Africa...

  6. The Blue Baby Syndrome

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 10. The Blue Baby Syndrome - Nitrate Poisoning in Humans. Deepanjan Majumdar. General Article Volume 8 Issue 10 October 2003 pp 20-30. Fulltext. Click here to view fulltext PDF. Permanent link:

  7. [Long-term effects of traumatic experiences on somatic and psychic complaints of German World War Two refugees].

    Science.gov (United States)

    Fischer, C J; Struwe, J; Lemke, M R

    2006-01-01

    The effects of expulsion from German territories following World War Two have not been studied systematically, and little is known about long-term effects of this potentially traumatic experience. Via mail, 600 refugees from former German territories due to World War Two were asked to complete questionnaires about biographic data, somatic and psychic health (SCL-90-R questionnaire), and specific aspects related to traumatic experiences (post-traumatic stress disorder questionnaire). Of those contacted, 25% participated in the investigation. Of them, 9.8% fulfilled diagnostic criteria of post-traumatic stress disorder according to DSM IV. Only 1.8% of an age-matched control group met these criteria. Analysis of the SCL-90-R questionnaire showed higher scores for former refugees in somatic and psychic complaints than the control group. We show that expulsion following war may lead to symptoms of post-traumatic stress disorder and somatic and psychic complaints after more than 50 years. Our investigation supports the necessity of adequate care for subjects expelled from their home countries and the psychologically traumatised.

  8. [Perception of pain in rheumatoid arthritis: relation to inflammation, psychic disorders, functional status, and quality of life].

    Science.gov (United States)

    Lisitsyna, T A; Vel'tishchev, D Iu; Gerasimov, A N; Seravina, O F; Kovalevskaia, O B; Zel'tyn', A E; Novikov, A A; Aleksandrova, E N; Tallerova, A V; Kovalenko, L P

    2013-01-01

    Pain perception was analyzed depending on the inflammatory activity of rheumatoid arthritis (RA), variants and manifestations of psychic disorders (including depressive, anxious and moderate cognitive ones), chronic fatigue, changes in the functional status and quality of life. The study included 125 patients (mean age 47.4 +/- 1.01 yr) with definitive diagnosis of RA 138.4 +/- 10.1 months in duration. RA activity was estimated from the DAS28 index, pain intensity and degree of fatigue by BPI and FSS scales respectively, the functional status and life quality by HAQ and EQ-5D. Psychic disorders were diagnosed by a psychiatrist in accordance with ICD-10 with the use of relevant psychiatric and psychological scales and methods. Pain perception was unrelated to the patients' age and RA duration. The multifactor analysis provided a basis for the prognostic model suggesting that the most severe pain in RA is related to the functional status and quality of life (VAS of general health status), hsCRP level, inflammatory activity index RA DAS28, peripheral platelet count, degree of fatigue (FSS) and depression (YADS), female sex. Depression and its severity is one more factor influencing pain perception in RA and accounting for functional insufficiency and low quality of life. Early diagnostics of psychic disorders (in the first place anxious and depressive ones) is mandatory to ensure effective combined therapy of pain in RA patients.

  9. Enrico Morselli's Psychology and "Spiritism": psychiatry, psychology and psychical research in Italy in the decades around 1900.

    Science.gov (United States)

    Brancaccio, Maria Teresa

    2014-12-01

    This paper traces Enrico Morselli's intellectual trajectory from the 1870s to the early 1900s. His interest in phenomena of physical mediumship is considered against the backdrop of the theoretical developments in Italian psychiatry and psychology. A leading positivist psychiatrist and a prolific academic, Morselli was actively involved in the making of Italian experimental psychology. Initially sceptical of psychical research and opposed to its association with the 'new psychology', Morselli subsequently conducted a study of the physical phenomena produced by the medium Eusapia Palladino. He concluded that her phenomena were genuine and represented them as the effects of an unknown bio-psychic force present in all human beings. By contextualizing Morselli's study of physical mediumship within contemporary theoretical and disciplinary discourse, this study elaborates shifts in the interpretations of 'supernormal' phenomena put forward by leading Italian psychiatrists and physiologists. It demonstrates that Morselli's interest in psychical research stems from his efforts to comprehend the determinants of complex psychological phenomena at a time when the dynamic theory of matter in physics, and the emergence of neo-vitalist theories influenced the theoretical debates in psychiatry, psychology and physiology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Visual Hypo and Hypergnosia as Exemplars of Poles of Psychic Tonus in the Occipital Lobes: Multiple Case Analyses

    Directory of Open Access Journals (Sweden)

    Claude M. J. Braun

    2008-01-01

    Full Text Available The “psychic tonus” model or PTM [1] of hemispheric specialization states that the left hemisphere is a psychic and behavioral activator and that the right hemisphere is an inhibitor. The PTM predicts that the tonus of visual representation ought to manifest hemispheric specialization in the occipital lobes. Specifically PTM predicts that pathological positive visual tonus (visual hallucination ought to be associated more frequently with right occipital lesions. PTM also predicts that pathological negative visual tonus (loss of visual imagery ought to result more often from left occipital lesions. We reviewed 78 cases of post lesion hallucination and 12 cases of post lesion loss of evocation of images, all following a unilateral lesion. Analyses of these relevant previously published cases support the predictions. In accordance with previously published demonstrations of hemispheric specialization for auditory tonus in the temporal lobes and for somesthetic tonus in the parietal lobes, the present findings extend the psychic tonus model of hemispheric specialization to vision in the occipital lobes.

  11. Trauma, dream, and psychic change in psychoanalyses: a dialog between psychoanalysis and the neurosciences

    Science.gov (United States)

    Fischmann, Tamara; Russ, Michael O.; Leuzinger-Bohleber, Marianne

    2013-01-01

    To many psychoanalysts dreams are a central source of knowledge of the unconscious—the specific research object of psychoanalysis. The dialog with the neurosciences, devoted to the testing of hypotheses on human behavior and neurophysiology with objective methods, has added to psychoanalytic conceptualizations on emotion, memory, sleep and dreams, conflict and trauma. To psychoanalysts as well as neuroscientists, the neurological basis of psychic functioning, particularly concerning trauma, is of special interest. In this article, an attempt is made to bridge the gap between psychoanalytic findings and neuroscientific findings on trauma. We then attempt to merge both approaches in one experimental study devoted to the investigation of the neurophysiological changes (fMRI) associated with psychoanalytic treatment in chronically depressed patients. We also report on an attempt to quantify psychoanalysis-induced transformation in the manifest content of dreams. To do so, we used two independent methods. First, dreams reported during the cure of chronic depressed analysands were assessed by the treating psychoanalyst. Second, dreams reported in an experimental context were analyzed by an independent evaluator using a standardized method to quantify changes in dream content (Moser method). Single cases are presented. Preliminary results suggest that psychoanalysis-induced transformation can be assessed in an objective way. PMID:24381554

  12. Object loss, renewed mourning, and psychic change in Jane Austen's Persuasion.

    Science.gov (United States)

    Hanly, Margaret Ann Fitzpatrick

    2007-08-01

    Austen's extraordinary realism in depicting the dynamic internal processes which follow on the heroine's loss in Persuasion becomes clear in the light of a psychoanalytic understanding of mourning. Persuasion dramatizes the effects of a mother's death in adolescence as these come into play at the time of the heroine's separation from her fiancée and her later mourning. The thesis of this paper is that, despite falling in love with the brilliant hero, an unfinished mourning and an unconscious identification with her dead mother helped to persuade the heroine Anne Elliot to break her engagement, to create a 'final parting' as her mother had done to her in dying. The heroine's internal monologues show that she has projected some of the darker feelings of mourning, her anger and resentment, on to the hero and that she reopens a complex mourning process, partly through the displacement of affect, showing how traumatic effects of loss can be worked through in deferred action, effecting positive psychic change.

  13. Trauma, dream and psychic change in psychoanalyses: a dialogue between psychoanalysis and the neurosciences

    Directory of Open Access Journals (Sweden)

    Tamara eFischmann

    2013-12-01

    Full Text Available To many psychoanalysts dreams are a central source of knowledge of the unconscious – the specific research object of psychoanalysis. The dialogue with the neurosciences, devoted to the testing of hypotheses on human behaviour and neurophysiology with objective methods, has added to psychoanalytic conceptualizations on emotion, memory, sleep and dreams, conflict and trauma. To psychoanalysts as well as neuroscientists, the neurological basis of psychic functioning, particularly concerning trauma, is of special interest. In this article, an attempt is made to bridge the gap between psychoanalytic findings and neuroscientific findings on trauma. We then attempt to merge both approaches in one experimental study devoted to the investigation of the neurophysiological changes (fMRI associated with psychoanalytic treatment in chronically depressed patients. We also report on an attempt to quantify psychoanalysis-induced transformation in the manifest content of dreams. To do so, we used two independent methods. First, dreams reported during the cure of chronic depressed analysands were assessed by the treating psychoanalyst. Second, dreams reported in an experimental context were analysed by an independent evaluator using a standardized method to quantify changes in dream content (Moser method. Single cases are presented. Preliminary results suggest that psychoanalysis-induced transformation can be assessed in an objective way.

  14. [Psychic disorders in emergency room: a qualitative analysis of psychological intervention].

    Science.gov (United States)

    Daini, S; Bernardini, L; Manzo, A; Petrongolo, L; Rossetti, R

    2012-01-01

    Our study aims to analyze typologies of psychological intervention that respond to spontaneous request of Emergency Room's users and care providers, and their distribution in relation to observed psychic disorders. 364 Subjects (134 males and 230 females), mean age 41.55 (± 22.38) reaching Emergency room were involved in this study. Data from an observation form were related to patients' triage code, their provisional diagnosis, the request of psychiatric advice and emergency outcome. Non-parametric variables were analyzed by Chi Square method, while parametric ones by ANOVA method. Patients were the more frequent users of psychological intervention, while relatives used it in lesser proportion. Anxiety Disorder was the most frequent psychiatric diagnosis associated to psychological consulting. The patient's triage code was not significantly related to frequency of consulting. The type of intervention that was most often choosen has been supportive. As to outcome, the majority of patients who consulted psychologists was discharged, while a low percentage was admitted, particularly in psychiatric wards. Psychological consulting appears related to a wider and more varied range of urgent situations than psychiatric consulting. Therefore, psychological intervention seems to be useful both to relieve hic et nunc psychological discomfort, and to help and direct sicker patients to formulate a long-term treatment plan.

  15. Does a previous surgical experience interfere on psychic stress in patients submitted to major surgery?

    Directory of Open Access Journals (Sweden)

    Luiz Ronaldo Alberti

    Full Text Available OBJECTIVE: to evaluate the impact of stress in patients undergoing major surgeries under general anesthesia, relating their physical and psychic reactions to the different stages of stress. METHODS: we studied 100 adult patients of both genders, who were divided into two groups: Group 1 - 22 patients without experience with surgery; Group 2 - 78 patients previously submitted to medium and major surgery. To investigate the stress, we used the Inventory of Stress Symptoms for Adults, developed by Lipp, the day before the procedure and two days and seven days after the operation. The comparison of groups with respect to gender, pain, and percentage of stress were performed using the Chi-square test, and for the age variable the Student's t test was used. Differences were considered significant at p<0.05. RESULTS: the groups were not homogeneous as for the overall percentage of stress on the three measurements. G1 had decreased postoperative stress, whilst in G2 it increased. Psychological symptoms of stress prevailed in both groups. CONCLUSION: previous surgery reduced preoperative stress but did not affect postoperative emotional disorders.

  16. 'What to do with anger?': Psychic osmosis, Sylvia Plath and Virginia Woolf

    Directory of Open Access Journals (Sweden)

    Mušović Azra A.

    2013-01-01

    Full Text Available According to Virginia Woolf, we think back through our mothers if we are women. It is useless to go to the great men writers for help, however much we may go to them for pleasure. Plath took Woolf as a model very early in her career. She undoubtedly considered Woolf the greatest woman writer of the century. But beyond that appeal, she identified her own life pattern with the one she saw in Woolf. This paper considers Plath's creative acts within the context of her relationship with biological mother, described as a sometimes wonderful, sometimes unwelcome sort of 'psychic osmosis', and within the context of other creative acts by women. The question of what to do with anger becomes Plath's key personal and creative question for studying the ways she lays claim to her matrilineal inheritance. This method assumes that literary influence retraces the outlines of the initial parent-child bond. And the most prominent writer who showed her what it meant to be a powerful female creator, the writer whose creative acts incorporated her life and whose death doubled her words - that literary mother was Virginia Woolf. Plath opened herself to what she believed to be a power associated with Woolf, a power intended to transform the influence of the biological mother. As a result, the texts of the two writers interact across time.

  17. In Search of a Definition of Bullying : Revisiting Psychic Damage Need for Your Configuration

    Directory of Open Access Journals (Sweden)

    Renato de Almeida Oliveira Muçouçah

    2016-06-01

    Full Text Available This research aims study the mobbing phenomenon and seek to place it beyond the borders of persecution or psychological damage, as can be observed on very recent court decisions. After a brief historical introduction about the fundamentals required to recognize an employment relationship as valid, and also trying to understand relationships where there is not formal characterization, the directive power of the employer and the form of its manifestation can be constituted in facilitating elements to practice of mobbing. The next act seeks to propose a broad definition of mobbing, not just based on psychic damage, in order to cover various forms of violence in employment relationships, with the desire to give them ways to legal protection to suppress or prevent such practices. The directive power of the employer eventually can become the productive force and the pressure in the culture of companies, which may constitute the mobbing, although whether or not damages of any kind. It is necessary, therefore, a reinterpretation of the concept of mobbing, which defends them with more promptness relations considered “normal” in the workplace, but which, in fact, are violent acts of disrespect about fundamental rights of the worker.

  18. Nanocrystal quantum dots

    CERN Document Server

    Klimov, Victor I

    2010-01-01

    ""Soft"" Chemical Synthesis and Manipulation of Semiconductor Nanocrystals, J.A. Hollingsworth and V.I. Klimov Electronic Structure in Semiconductor Nanocrystals: Optical Experiment, D.J. NorrisFine Structure and Polarization Properties of Band-Edge Excitons in Semiconductor Nanocrystals, A.L. EfrosIntraband Spectroscopy and Dynamics of Colloidal Semiconductor Quantum Dots, P. Guyot-Sionnest, M. Shim, and C. WangMultiexciton Phenomena in Semiconductor Nanocrystals, V.I. KlimovOptical Dynamics in Single Semiconductor Quantum Do

  19. Evidence for Phase-Separated Quantum Dots in Cubic InGaN Layers from Resonant Raman Scattering

    Science.gov (United States)

    Lemos, V.; Silveira, E.; Leite, J. R.; Tabata, A.; Trentin, R.; Scolfaro, L. M. R.; Frey, T.; As, D. J.; Schikora, D.; Lischka, K.

    2000-04-01

    The emission of light in the blue-green region from cubic InxGa1-xN alloys grown by molecular beam epitaxy is observed at room temperature and 30 K. By using selective resonant Raman spectroscopy (RRS) we demonstrate that the emission is due to quantum confinement effects taking place in phase-separated In-rich quantum dots formed in the layers. RRS data show that the In content of the dots fluctuates across the volume of the layers. We find that dot size and alloy fluctuation determine the emission wavelengths.

  20. Silanization of Low-Temperature-Plasma Synthesized Silicon Quantum Dots for Production of a Tunable, Stable, Colloidal Solution

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, I. E.; Shircliff, R. A.; Macauley, C.; Smith, D. K.; Lee, B. G.; Agrawal, S.; Stradins, P.; Collins, R. T.

    2012-02-16

    We present a method for grafting silanes onto low-temperature-plasma synthesized silicon quantum dots. The resulting solution of dots is characterized with Fourier transform infrared spectroscopy and transmission electron microscopy, and determined to be a colloidal suspension. The silane is attached at a single point on the quantum dot surface to avoid cross-linking and multilayer formation, and photoluminescence spectroscopy shows the colloidal suspension of dots is stable for over two months in air. The hydroxyl-terminated surfaces required for silanization are created by wet chemical etch, which can be used to tune the luminescence of the silicon dots in the green- to red-wavelength range. We find, however, that the wet etch cannot move the emission into the blue-wavelength range and discuss this observation in terms of the nature of etching process and origin of the emission. In addition, we discuss the photoluminescence quantum yield in the context of other passivation and synthetic techniques.

  1. Stochastic clustered-dot dithering

    Science.gov (United States)

    Ostromoukhov, Victor; Hersch, Roger D.

    1999-10-01

    A new technique for building stochastic clustered-dot screens is being proposed. A large dither matrix comprising thousands of stochastically laid out screen dots is constructed by first laying out the screen dot centers. Screen dot centers are obtained by placing discrete disks of a chosen radius at free cell locations when traversing the dither array cells according to either a discretely rotated Hilbert space-filling curve or a random space-filling curve. After Delauney triangulation of the screen dot centers, the maximal surface of each screen dot is computed and isointensity regions are created. This isointensity map is converted into an antialiased gray scale image, i.e., into an array of preliminary threshold values. These threshold values are renumbered to obtain the threshold values of the final dither threshold array. By changing the disk radius, the screen dot size can be adapted to the characteristics of particular printing devices. Larger screen dots may improve the one reproduction of printers having important dot gain.

  2. [Blue light and eye health].

    Science.gov (United States)

    Zou, Leilei; Dai, Jinhui

    2015-01-01

    Blue light, with the wavelength between 400 nm and 500 nm, has caused public concern because of the injury to the retinal cells. Meanwhile, it is important in circadian rhythm regulation, scotopic vision and ocular growth. Is the blue light safe? Should it be eliminated from the daily life? Here we review the effect and safety of the blue light.

  3. Chlorine-functionalized carbon dots for highly efficient photodegradation of pollutants under visible-light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Shengliang, E-mail: hsliang@yeah.net [School of Material Science and Engineering, North University of China, Taiyuan 030051 (China); Ding, Yanli [School of Material Science and Engineering, North University of China, Taiyuan 030051 (China); Chang, Qing, E-mail: changneu@gmail.com [School of Material Science and Engineering, North University of China, Taiyuan 030051 (China); Yang, Jinlong [State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China); Lin, Kui, E-mail: linkui@tju.edu.cn [Analytical Instrumentation Center, Tianjin University, Tianjin 300072 (China)

    2015-11-15

    Graphical abstract: Chlorine-functionalized carbon dots (Cl-CDs) were synthesized through the substitution reaction. Cl-CDs show highly photocatalytic activity under visible-light irradiation, and can quickly degrade phthalocyanine with the thermal and chemical stability. This work suggests that surface engineering of carbon dots with heteroatoms can be used to enhance their photochemical properties. - Highlights: • Chlorine-functionalized carbon dots (Cl-CDs) were synthesized by substitution reaction. • Cl-CDs show highly photocatalytic activity under visible-light irradiation. • The thermally and chemically stable phthalocyanine is even photodegraded by Cl-CDs. - Abstract: Chlorine-functionalized carbon dots (Cl-CDs) were prepared by the substitution reaction between Cl radicals into thionyl chloride molecules and carbon dots with containing OH/COOH groups at their surface (O-CDs). The obtained Cl-CDs with a size of 2–5 nm contain 2–3% Cl atoms and emit blue light. Compared with amine-functionalzed carbon dots (N-CDs) and O-CDs, Cl-CDs exhibit much higher photocatalytic activity under visible-light irradiation. The thermally and chemically stable phthalocyanine can be even degraded quickly through Cl-CDs. This work suggests that surface engineering of carbon dots with heteroatoms can be used to enhance their photochemical properties.

  4. Nanostructure assembly of indium sulphide quantum dots and their characterization.

    Science.gov (United States)

    Vigneashwari, B; Ravichandran, V; Parameswaran, P; Dash, S; Tyagi, A K

    2008-02-01

    Nanocrystals (approximately 5 nm) of the semiconducting wide band gap material beta-In2S3 obtained by chemical synthesis through a hydrothermal route were characterized for phase and compositional purity. These nanoparticles exhibited quantum confinement characteristics as revealed by a blue-shifted optical absorption. These quantum dots of beta-In2S3 were electrically driven from a monodisperse colloidal suspension on to conducting glass substrates by Electophoretic Deposition (EPD) technique and nanostructural thin films were obtained. The crystalline and morphological structures of these deposits were investigated by X-ray diffraction and nanoscopic techniques. We report here that certain interesting nanostructural morphologies were observed in the two-dimensional quantum dot assemblies of beta-In2S3. The effect of the controlling parameters on the cluster growth and deposit integrity was also systematically studied through a series of experiments and the results are reported here.

  5. Optical and Micro-Structural Characterization of MBE Grown Indium Gallium Nitride Polar Quantum Dots

    KAUST Repository

    El Afandy, Rami

    2011-07-07

    Gallium nitride and related materials have ushered in scientific and technological breakthrough for lighting, mass data storage and high power electronic applications. These III-nitride materials have found their niche in blue light emitting diodes and blue laser diodes. Despite the current development, there are still technological problems that still impede the performance of such devices. Three-dimensional nanostructures are proposed to improve the electrical and thermal properties of III-nitride optical devices. This thesis consolidates the characterization results and unveils the unique physical properties of polar indium gallium nitride quantum dots grown by molecular beam epitaxy technique. In this thesis, a theoretical overview of the physical, structural and optical properties of polar III-nitrides quantum dots will be presented. Particular emphasis will be given to properties that distinguish truncated-pyramidal III-nitride quantum dots from other III-V semiconductor based quantum dots. The optical properties of indium gallium nitride quantum dots are mainly dominated by large polarization fields, as well as quantum confinement effects. Hence, the experimental investigations for such quantum dots require performing bandgap calculations taking into account the internal strain fields, polarization fields and confinement effects. The experiments conducted in this investigation involved the transmission electron microscopy and x-ray diffraction as well as photoluminescence spectroscopy. The analysis of the temperature dependence and excitation power dependence of the PL spectra sheds light on the carrier dynamics within the quantum dots, and its underlying wetting layer. A further analysis shows that indium gallium nitride quantum dots through three-dimensional confinements are able to prevent the electronic carriers from getting thermalized into defects which grants III-nitrides quantum dot based light emitting diodes superior thermally induced optical

  6. Resonant-enhanced full-color emission of quantum-dot-based micro LED display technology.

    Science.gov (United States)

    Han, Hau-Vei; Lin, Huang-Yu; Lin, Chien-Chung; Chong, Wing-Cheung; Li, Jie-Ru; Chen, Kuo-Ju; Yu, Peichen; Chen, Teng-Ming; Chen, Huang-Ming; Lau, Kei-May; Kuo, Hao-Chung

    2015-12-14

    Colloidal quantum dots which can emit red, green, and blue colors are incorporated with a micro-LED array to demonstrate a feasible choice for future display technology. The pitch of the micro-LED array is 40 μm, which is sufficient for high-resolution screen applications. The method that was used to spray the quantum dots in such tight space is called Aerosol Jet technology which uses atomizer and gas flow control to obtain uniform and controlled narrow spots. The ultra-violet LEDs are used in the array to excite the red, green and blue quantum dots on the top surface. To increase the utilization of the UV photons, a layer of distributed Bragg reflector was laid down on the device to reflect most of the leaked UV photons back to the quantum dot layers. With this mechanism, the enhanced luminous flux is 194% (blue), 173% (green) and 183% (red) more than that of the samples without the reflector. The luminous efficacy of radiation (LER) was measured under various currents and a value of 165 lm/Watt was recorded.

  7. Cirurgia espiritual: uma investigação Psychic surgery: an investigation

    Directory of Open Access Journals (Sweden)

    A.M. de Almeida

    2000-09-01

    Full Text Available OBJETIVO: Uma modalidade de tratamento que capta muito a atenção da mídia é a cirurgia espiritual, que, entretanto, tem sido pouco estudada cientificamente. Uma questão que se impõe é sobre a veracidade ou não de tais fenômenos, porém pesquisas nesse sentido são escassas. MÉTODO: Apresentamos o relato de uma investigação sobre um dos mais famosos cirurgiões espirituais do Brasil, o Sr. João Teixeira de Farias. Foram acompanhadas por volta de 30 "cirurgias", sendo que em seis dos pacientes foram realizados a anamnese, o exame físico e coletados os tecidos extraídos para exames anatomo-patológicos. RESULTADOS: O "cirurgião" verdadeiramente incisa a pele ou o epitélio ocular, além de realizar raspados corneanos sem nenhuma técnica anestésica ou antisséptica identificável. Apesar disso, apenas um paciente queixou-se de dor moderada quando teve a mama incisada. Os pacientes foram examinados até três dias depois da cirurgia sem nenhum sinal de infecção, bem como os relatos posteriores dos pacientes não continham informações de infecção. O exame histopatológico evidenciou que os tecidos extraídos eram compatíveis com o local de origem e, com exceção de um lipoma de 210 gramas, eram tecidos normais, sem particularidades patológicas. Foi realizada revisão da literatura e discussão do efeito placebo. CONCLUSÕES: As cirurgias são reais, mas, apesar de não ter sido possível avaliar a eficácia do procedimento, aparentemente não teriam efeito específico na cura dos pacientes. Sem dúvida, nossos achados são mais exploratórios que conclusivos. São necessários posteriores estudos para lançar luz sobre esse heterodoxo tratamento.BACKGROUND: A very popular modality with the media is psychic surgery which has received little scientific evaluation though. Such phenomena always raise the issues of fakery and deceit. Research has been scarce. METHODS: We report an investigation on one of the most famous psychic

  8. Embracing the family member the person in psychic suffering in nursing studies

    Directory of Open Access Journals (Sweden)

    Cristiene Barbosa Lima

    2014-09-01

    Full Text Available Objective: To evidence knowledge published in the field of nursing care on the embracement to family members of people in psychic suffering in health services. Methods: Integrative review, accomplished in June and July 2012, in LILACS, BDENF, IBECS, MEDLINE and SciELO databases, using the keywords: “mental health”, “user embracement” and “family”. The inclusion criteria were met by 14 texts, written by professionals and nursing students, in Portuguese language, published between 2007 and 2011. The data was resumed in four tables and a figure, and analyzed under the framework of the user embracement by the National Humanization Policy. Results: No trends related to studies on user embracement can be stated. Most publications adopt a qualitative approach and content analysis, with evidence being type III. There is a predominance of research having health professionals as subjects. However, the family and other actors are starting to get involved. Taking similar care of the family and the person in suffering is highlighted in all of the studies analyzed. It was evidenced need for interaction between the health services and the specialized mental health network and for training the team in order to minimize to the difficulties faced by the family. Conclusion: Family embracement was often pointed as a device that facilitates the rehabilitation. There is much to be done toward its embracement in health services, so that the family is allowed to realize that their living is not necessarily the continuity of the trouble faced by the other person. doi:http://dx.doi.org/10.5020/18061230.2013.p571

  9. Psychometric Properties of "Community Assessment of Psychic Experiences": Review and Meta-analyses.

    Science.gov (United States)

    Mark, Winifred; Toulopoulou, Timothea

    2016-01-01

    The Community Assessment of Psychic Experiences (CAPE) has been used extensively as a measurement for psychosis proneness in clinical and research settings. However, no prior review and meta-analysis have comprehensively examined psychometric properties (reliability and validity) of CAPE scores across different studies. To study CAPE's internal reliability--ie, how well scale items correlate with one another--111 studies were reviewed. Of these, 18 reported unique internal reliability coefficients using data at hand, which were aggregated in a meta-analysis. Furthermore, to confirm the number and nature of factors tapped by CAPE, 17 factor analytic studies were reviewed and subjected to meta-analysis in cases of discrepancy. Results suggested that CAPE scores were psychometrically reliable--ie, scores obtained could be attributed to true score variance. Our review of factor analytic studies supported a 3-factor model for CAPE consisting of "Positive", "Negative", and "Depressive" subscales; and a tripartite structure for the Negative dimension consisting of "Social withdrawal", "Affective flattening", and "Avolition" subdimensions. Meta-analysis of factor analytic studies of the Positive dimension revealed a tridimensional structure consisting of "Bizarre experiences", "Delusional ideations", and "Perceptual anomalies". Information on reliability and validity of CAPE scores is important for ensuring accurate measurement of the psychosis proneness phenotype, which in turn facilitates early detection and intervention for psychotic disorders. Apart from enhancing the understanding of psychometric properties of CAPE scores, our review revealed questionable reporting practices possibly reflecting insufficient understanding regarding the significance of psychometric properties. We recommend increased focus on psychometrics in psychology programmes and clinical journals. © The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric

  10. Psychometric Properties of “Community Assessment of Psychic Experiences”: Review and Meta-analyses

    Science.gov (United States)

    Mark, Winifred; Toulopoulou, Timothea

    2016-01-01

    The Community Assessment of Psychic Experiences (CAPE) has been used extensively as a measurement for psychosis proneness in clinical and research settings. However, no prior review and meta-analysis have comprehensively examined psychometric properties (reliability and validity) of CAPE scores across different studies. To study CAPE’s internal reliability—ie, how well scale items correlate with one another—111 studies were reviewed. Of these, 18 reported unique internal reliability coefficients using data at hand, which were aggregated in a meta-analysis. Furthermore, to confirm the number and nature of factors tapped by CAPE, 17 factor analytic studies were reviewed and subjected to meta-analysis in cases of discrepancy. Results suggested that CAPE scores were psychometrically reliable—ie, scores obtained could be attributed to true score variance. Our review of factor analytic studies supported a 3-factor model for CAPE consisting of “Positive”, “Negative”, and “Depressive” subscales; and a tripartite structure for the Negative dimension consisting of “Social withdrawal”, “Affective flattening”, and “Avolition” subdimensions. Meta-analysis of factor analytic studies of the Positive dimension revealed a tridimensional structure consisting of “Bizarre experiences”, “Delusional ideations”, and “Perceptual anomalies”. Information on reliability and validity of CAPE scores is important for ensuring accurate measurement of the psychosis proneness phenotype, which in turn facilitates early detection and intervention for psychotic disorders. Apart from enhancing the understanding of psychometric properties of CAPE scores, our review revealed questionable reporting practices possibly reflecting insufficient understanding regarding the significance of psychometric properties. We recommend increased focus on psychometrics in psychology programmes and clinical journals. PMID:26150674

  11. [Chronic Pelvic Pain Syndrome and Personality--Association of Somatic Symptoms and Psychic Structure].

    Science.gov (United States)

    Albrecht, Rebecca; Löwe, Bernd; A Brünahl, Christian; Riegel, Björn

    2015-11-01

    Despite its high prevalence, little is known about the aetiology and maintenance of Chronic Pelvic Pain Syndrome (CPPS). CPPS is is considered to be a multi-causal syndrome with discomfort and pain in the pelvis. Recent literature suggests that psychosocial factors are important for understanding CPPS. For example, CPPS has been associated with deficits in mentalization and bonding experiences. Our study aims to characterize features of personality disorders according to DSM-IV and psychic structure according to OPD-2 in CPPS patients. Furthermore, we examine the association of personality aspects with urological symptoms (NIH Questionnaire) and pain perception (MPQ Questionnaire). Personality aspects were assessed in a total of 109 patients from our CPPS outpatient clinic using standardized questionnaires. To characterize CPPS patients, we compared the sample's scores with reference groups, mostly the general population. In addition, the associations between personality aspects and both the urologic symptoms and pain perception were assessed using correlations. Missing data were replaced using multiple imputation methods. Compared to reference values, we found 'experiencing emotions' and 'creating relationships' as specific deficits in CPPS patients. Furthermore, patients' self-image (more dominant, higher depressive mood) differs from the general population. A higher pain perception was correlated with deficits in most personality aspects we measured. However, this was not the case for the severity of urological symptoms. Compared to the reference values, only a few personality aspects differed in CPPS patients but there was a correlational association between different personality traits and pain perception. Despite the extend of symptoms, pain perception is associated with difficulty (emotional ability) in dealing with emotions, self-management and relationships. These personality aspects should be taken into account when planning therapy. © Georg Thieme

  12. [The role of psychic factors in the pathogenesis of bronchial asthma].

    Science.gov (United States)

    Vucević, Danijela; Radosavljević, Tatjana; Mladenović, Dusan; Todorović, Vera

    2011-01-01

    Bronchial asthma is a chronic inflammatory disorder of the airways in which many cells play a role, in particular mast cells, eosinophils, neutrophils, T-lymphocytes and epithelial cells. In susceptible individuals this inflammation causes recurrent episodes of wheezing, breathlessness, chest tightness and cough, particularly at night and/or in the early morning. These symptoms are usually associated with variable and extensive limitations of airflow in the bronchi reversible spontaneously or by treatment. It has been shown that restrain of the effectors of stress response participate in the pathogenesis of bronchial asthma. Anger that is not expressed and frustrations may activate the limbic stress pathway. Thus, the released neurotransmitters followed by excitation thus causing psychogenic (mental or emotional) stress. It is also known that emotional stress may be responsible for the exacerbation of asthma. Namely, pronounced emotions cause hyperventilation and hypocapnia inducing bronchospasm. Certain psychological personality features are related to adaptive or inadequate body response to numerous life events. Thus, until the beginning of the last century, bronchial asthma was referred to as asthma nervosa, because clinicians clearly observed the psychological profile of patients with predominant fear of asphyxia and recurrent attacks of paroxysmal dyspnoea. Besides, increased sensitivity, repression of aggressive feelings and expressive empathy have been identified as the most frequent psychological characteristics of asthmatic patients. However, scientists are still far from a full understanding of bronchial asthma pathogenesis. The contribution of psychic factors has become meaningful in the understanding of the development of bronchial asthma. Having in mind that in the majority of patients asthma is a lifelong condition, there is a hope that further investigations of bronchial asthma psychogenesis will improve prevention and treatment of this disease.

  13. The role of psychic factors in the pathogenesis of bronchial asthma

    Directory of Open Access Journals (Sweden)

    Vučević Danijela

    2011-01-01

    Full Text Available Bronchial asthma is a chronic inflammatory disorder of the airways in which many cells play a role, in particular mast cells, eosinophils, neutrophils, T-lymphocytes and epithelial cells. In susceptible individuals this inflammation causes recurrent episodes of wheezing, breathlessness, chest tightness and cough, particularly at night and/or in the early morning. These symptoms are usually associated with variable and extensive limitations of airflow in the bronchi reversible spontaneously or by treatment. It has been shown that restrain of the effectors of stress response participate in the pathogenesis of bronchial asthma. Anger that is not expressed and frustrations may activate the limbic stress pathway. Thus, the released neurotransmitters followed by excitation thus causing psychogenic (mental or emotional stress. It is also known that emotional stress may be responsible for the exacerbation of asthma. Namely, pronounced emotions cause hyperventilation and hypocapnia inducing bronchospasm. Certain psychological personality features are related to adaptive or inadequate body response to numerous life events. Thus, until the beginning of the last century, bronchial asthma was referred to as asthma nervosa, because clinicians clearly observed the psychological profile of patients with predominant fear of asphyxia and recurrent attacks of paroxysmal dyspnoea. Besides, increased sensitivity, repression of aggressive feelings and expressive empathy have been identified as the most frequent psychological characteristics of asthmatic patients. However, scientists are still far from a full understanding of bronchial asthma pathogenesis. The contribution of psychic factors has become meaningful in the understanding of the development of bronchial asthma. Having in mind that in the majority of patients asthma is a lifelong condition, there is a hope that further investigations of bronchial asthma psychogenesis will improve prevention and treatment of

  14. Synthesis of colloidal SnSe quantum dots by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhen; Peng Liwei; Fang Yaoguo; Chen Zhiwen [Shanghai Applied Radiation Institute, Shanghai University, Shanghai 201800 (China); Pan Dengyu [Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 201800 (China); Wu Minghong, E-mail: mhwu@staff.shu.edu.cn [Shanghai Applied Radiation Institute, Shanghai University, Shanghai 201800 (China)

    2011-12-15

    Water-soluble orthorhombic colloidal SnSe quantum dots with an average diameter of 4 nm were successfully prepared by a novel irradiation route using an electronic accelerator as a radiation source and hexadecyl trimethyl ammonium bromide (CTAB) as a surfactant. The quantum dots exhibit a large direct bandgap of 3.89 eV, greatly blue shifted compared with that of bulk SnSe (1.0 eV) due to the quantum confinement effect. The quantum dots show blue photoluminescence at {approx}420 nm. The influence of CTAB on the growth of the quantum dots was investigated and a possible reaction/growth mechanism was proposed. - Highlights: > A rapid, facile and green strategy is developed to synthesize SnSe QDs. > The raw materials are green and easily obtained. > The surfactant CTAB plays an important role in the formation of SnSe quantum dots. > The obtained SnSe QDs is well-dispersed with the average size of around 4 nm.

  15. Tuning the Photoluminescence of Graphene Quantum Dots by Fluorination

    Directory of Open Access Journals (Sweden)

    Yi Luo

    2017-01-01

    Full Text Available Fluorinated graphene quantum dots (F-GQDs were prepared by mixing GQDs and XeF2 in a facile gaseous phase heating method. The F-GQDs with excellent water solubility have a F/C atomic ratio of 84.25% and a diameter of 2–6 nm. The photoluminescence (PL properties of GQDs and F-GQDs were investigated systematically. The results showed that the PL emission of the F-GQDs exhibited an obvious blue-shift of 90 nm compared to that of the GQDs.

  16. Red Dot Basal Cell Carcinoma

    Science.gov (United States)

    2017-01-01

    Red dot basal cell carcinoma, a distinctive morphologic variant of basal cell carcinoma that presents as a small red macule (dot) or papule, is described on a woman’s thigh. A high index of suspicion is necessary to consider the diagnosis since the tumor mimics a telangiectasia or an angioma. PMID:28670359

  17. Solid-phase synthesis of highly fluorescent nitrogen-doped carbon dots for sensitive and selective probing ferric ions in living cells.

    Science.gov (United States)

    Zhang, Haijuan; Chen, Yonglei; Liang, Meijuan; Xu, Laifang; Qi, Shengda; Chen, Hongli; Chen, Xingguo

    2014-10-07

    Carbon quantum dots (C-Dots) have drawn extensive attention in recent years due to their stable physicochemical and photochemical properties. However, the development of nitrogen-doped carbon quantum dots (N-doped C-Dots) is still on its early stage. In this paper, a facile and high-output solid-phase synthesis approach was proposed for the fabrication of N-doped, highly fluorescent carbon quantum dots. The obtained N-doped C-Dots exhibited a strong blue emission with an absolute quantum yield (QY) of up to 31%, owing to fluorescence enhancement effect of introduced N atoms into carbon dots. The strong coordination of oxygen-rich groups on N-doped C-Dots to Fe(3+) caused fluorescence quenching via nonradiative electron-transfer, leading to the quantitative detection of Fe(3+). The probe exhibited a wide linear response concentration range (0.01-500 μM) to Fe(3+) with a detection limit of 2.5 nM. Significantly, the N-doped C-Dots possess negligible cytotoxicity, excellent biocompatibility, and high photostability. All these features are favorable for label-free monitoring of Fe(3+) in complex biological samples. It was then successfully applied for the fluorescence imaging of intracellular Fe(3+). As an efficient chemosensor, the N-doped C-Dots hold great promise to broaden applications in biological systems.

  18. [Assessment of the capability of performance of patients with psychic and psychosomatic diseases--a diagnostic model].

    Science.gov (United States)

    Schneider, W; Becker, D; Vogel, M; Freyberger, H J; Gündel, H; Henningsen, R; Köllner, V; Dohrenbusch, R

    2011-06-01

    The limited availability of appropriate methods and criteria makes the assessment of capability by psychic and psychosomatic disorders difficult. This article displays and discusses the standards relating to content and method in capability assessments. The underlying diagnostic model of assessment capability has been conceptualised and tested empirically by a multicentric and interdisciplinary work-group. Different diagnostic levels of the manual are outlined as well as the procedures of operationalisation of the diagnostic categories. Furthermore, first results of empirical analysis are described and important conditions of the application of the diagnostic model are discussed.

  19. [The incidence of the child psychic handicap in the department of Var in 2001 from CDES files].

    Science.gov (United States)

    Bourdais-Mannone, C; Jimeno, M-T

    2007-12-01

    Thanks to an automated treatment of the medical information of the Departmental Commission of the Special Education in the Var, set up since 1999, under the responsibility of an epidemiologist doctor, it is possible to measure the incidence rates of the children recognized as been handicapped. This study is the first one performed on the basis of good-quality and reliable medical and administrative informations. Moreover, this study has yielded thinking on the criteria of handicap definition and nomenclature to be used to define psychic deficiency. The occurrence rate of children recognized as handicapped by the Departmental Commission of the Var is 2.04%. The rate of children with a psychic deficiency recognized by the Commission is 1.25%. These rates are 2.5 times higher among boys than girls. Psychic deficiencies occurs mainly between five and nine years of age, at the entry to the primary school. The western part of the department displays rates of nevrotic, reactional, instrumental functions, and training disorders that are higher than those of the other geographical areas. For the eastern part of the department, the rates of psychoses, pathologies of the personality and evolutionary disorders are the highest. The distribution of declared pathologies probably reflects equipment of the medical sector of childpsychiatry and distribution of the liberal assumptions of responsibility. The geographical area of Draguignan is significantly under-equipped with medico-social structures but is characterized by a high rate of children with a psychic handicap. The Law of February 11 2005 for chance and equal right, stipulates a counting of the people affected by handicap and the underlying pathologies, to define the ethiology of the handicap, to improve the accompaniment of those people and to develop actions aimed at reducing the incapacities and at the prevention of risks. It is within the Departmental houses of the handicapped person that the information systems will

  20. A single molecule investigation of the photostability of quantum dots.

    Directory of Open Access Journals (Sweden)

    Eva Christensen Arnspang

    Full Text Available Quantum dots (QDs are very attractive probes for multi-color fluorescence imaging in biological applications because of their immense brightness and reported extended photostability. We report here however that single QDs, suitable for biological applications, that are subject to continuous blue excitation from a conventional 100 W mercury arc lamp will undergo a continuous blue-switching of the emission wavelength eventually reaching a permanent dark, photobleached state. We further show that β-mercaptoethanol has a dual stabilizing effect on the fluorescence emission of QDs: 1 by increasing the frequency of time that a QD is in its fluorescent state, and 2 by decreasing the photobleaching rate. The observed QD color spectral switching is especially detrimental for multi-color single molecule applications, as we regularly observe spectral blue-shifts of 50 nm, or more even after only ten seconds of illumination. However, of significant importance for biological applications, we find that even small, biologically compatible, concentrations (25 µM of β-mercaptoethanol has a significant stabilizing effect on the emission color of QDs, but that greater amounts are required to completely abolish the spectral blue shifting or to minimize the emission intermittency of QDs.

  1. Blue ocean leadership.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2014-05-01

    Ten years ago, two INSEAD professors broke ground by introducing "blue ocean strategy," a new model for discovering uncontested markets that are ripe for growth. In this article, they apply their concepts and tools to what is perhaps the greatest challenge of leadership: closing the gulf between the potential and the realized talent and energy of employees. Research indicates that this gulf is vast: According to Gallup, 70% of workers are disengaged from their jobs. If companies could find a way to convert them into engaged employees, the results could be transformative. The trouble is, managers lack a clear understanding of what changes they could make to bring out the best in everyone. Here, Kim and Mauborgne offer a solution to that problem: a systematic approach to uncovering, at each level of the organization, which leadership acts and activities will inspire employees to give their all, and a process for getting managers throughout the company to start doing them. Blue ocean leadership works because the managers' "customers"-that is, the people managers oversee and report to-are involved in identifying what's effective and what isn't. Moreover, the approach doesn't require leaders to alter who they are, just to undertake a different set of tasks. And that kind of change is much easier to implement and track than changes to values and mind-sets.

  2. Chemiluminescence of nitrogen-rich quantum dots in diperiodatoargentate(III) solution and its application in ferulic acid analysis.

    Science.gov (United States)

    Fu, Zhaofu; Li, Gongke; Hu, Yufei

    2016-12-01

    A novel chemiluminescence (CL) system based on the reaction of fluorescent water-soluble nitrogen-rich quantum dots (N-dots) and diperiodatoargentate(III) (DPA) was developed. The prepared N-dots have a small size (≤10 nm) and high percentage of nitrogen (39.9 %), which exceeds the content of carbon in the same N-dots. The N-dots exhibit characteristic blue fluorescence under UV light and up-conversion luminescence. The relatively intense CL emission is based on the direct oxidation of N-dots by DPA. The CL emission may be attributed to the high nitrogen content and the special structure of the N-dots. The CL mechanism of N-dots and DPA was investigated by using CL, UV-Vis absorption, IR, fluorescence, and radical scavenging experiments. This investigation provides a way to study the optical properties of N-dots. The analytical applicability of the N-dots and DPA CL system in the determination of ferulic acid (FA) was explored. The CL intensity was linearly proportional to the concentration of ferulic acid from 3.0 × 10(-7) to 1.0 × 10(-5) g mL(-1) with a detection limit of 8.0 × 10(-8) g mL(-1) (3σ); the relative standard deviation was 2.4 % for 4.0 × 10(-7) g mL(-1) FA (n = 9). The proposed method was successfully applied to the determination of ferulic acid in Angelica sinensis. The study provides valuable insight into the role of nitrogen-rich quantum dots in CL.

  3. Three-dimensional modeling of blue jets and blue starters

    National Research Council Canada - National Science Library

    Victor P. Pasko; Jeremy J. George

    2002-01-01

    .... Results from a three‐dimensional fractal model based on a phenomenological probabilistic approach to the modeling of streamer coronas indicate, in particular, that blue jets and blue starters can be formed by a fast (∼1 s) accumulation of ∼110...

  4. [Influence of antidepressant therapy on psychic state and functional and cognitive abilities elderly patients treated in psychiatric ward].

    Science.gov (United States)

    Tatarczuk, Joanna; Galus, Krzysztof; Kozak-Szkopek, Elzbieta; Kowalczyk, Alina

    2012-07-01

    Depression and cognitive disfunctions are the most common psychopathological disorders of older adults. To asses effects of a pharmacological and psychological treatment performed in psychiatric ward on psychic state and functional and cognitive abilities in elderly patients with depression. The study included group of 35 patients with depression (22 women and 13 men) above 65 years old, consecutively admitted to the psychiatric ward. Examination of the psychical, mental and functional abilities was performed at the beginning and end of 4-6 weeks treatment in psychiatric ward, by means of the following scales: Katz activities of daily living (ADL), Lawton instrumental activities of daily living scale (IADL), Folstein mini mental state examination (MMSE), Yesavage Geriatric Depression Scale (GDS). In women, after treatment the average scores in ADL test increased 0.3 point (statistically insignificant); in IADL test--increased 2.6 points (statistically significant); in MMSE test--increased 6 points (statistically significant), in GDS scale--reduced 13.45 points (statistically significant). In men after therapy the mean value of points in ADL test increased 0.4 points (statistically insignificant); in the test of IADL increased 3.5 points (statistically significant); in MMSE test--increased 6.5 points (statistically significant); in the scale of the GDS decreased 13.7 points (statistically highly significant). In elderly patients with depression mental state improved after pharmacological and psychological treatment in psychiatric ward. Improvement of mood in elderly patients treated for depression leads to increased functional and cognitive abilities.

  5. Correlational study between psychic symptoms and quality of life among hemodialysis patients older than 55 years of age.

    Science.gov (United States)

    De Pasquale, C; Pistorio, M L; Corona, D; Mistretta, A; Zerbo, D; Sinagra, N; Giaquinta, A; Tallarita, T; Esker, B; Mociskyte, D; Leonardi, A; Gula, R; Veroux, P; Veroux, M

    2012-09-01

    The loss of renal function and urination with dialysis can produce a strong emotional crisis in a patient. This study explored the correlation between psychic symptoms and quality of life among hemodialysis patients who were older than 55 years of age in relation to demographic characteristics of age, time on dialysis, and education. Twenty patients undergoing hemodialysis were included in the study. The psychic symptoms were studied using the Symptom Checklist-90. Revised (SCL-90 R) and the quality of life was studied using the Complete Form Health Survey (SF 36). The high correlation between psychological sizes investigated through the SCL-90 R test and those for the SF-36 test confirmed the close relationship between physical disorders and mental suffering, and reduced vitality, and lack of socialization. The psychiatrist and psychologist may help hemodialysis patients to improve their quality of life by providing new coping strategies for each of the family, occupational, and social network. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Implementing a tailored approach for the hand-injured patient: a prospective study on the evolution of the posttraumatic psychic distress.

    Science.gov (United States)

    Tocco, Ilaria; Azzi, Mariafrancesca; Salini, Elena; Bassetto, Franco

    2013-01-01

    Mutilating hand injuries are frequently associated with the development of psychic impairments such as posttraumatic stress disorder, depression, regression of the personality, and refusal of the disease. The psychic distress acts as a source of disability that outweighs the functional loss, causing impairments that may prevent a full recovery after the accident. The present study highlights the need for nurses to be familiar with the emotional response in the patients, to implement a specialized and comprehensive approach and detect stress points that may require early intervention.

  7. Instant BlueStacks

    CERN Document Server

    Judge, Gary

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A fast-paced, example-based approach guide for learning BlueStacks.This book is for anyone with a Mac or PC who wants to run Android apps on their computer. Whether you want to play games that are freely available for Android but not your computer, or you want to try apps before you install them on a physical device or use it as a development tool, this book will show you how. No previous experience is needed as this is written in plain English

  8. Natural Blue Food Colour

    DEFF Research Database (Denmark)

    Roda-Serrat, Maria Cinta

    design is a possible approach to help overcoming the present stability issues of phycocyanin-based colorants. This thesis presents a process for cleavage of PCB from phycocyanin by solvolysis in alcohols as a first step towards the formulation of a new natural blue colorant. A pre-treatment dia......, and a set of differential equations, the model was able to predict the behaviour of the flux with a confidence level above 95 %. Three different methods of cleavage of PCB by solvolysis were evaluated in this study: conventional reflux, sealed vessel heated in an oil bath, and microwave assisted reaction...... mechanisms are suggested: a concerted E2 elimination, and a SN2 nucleophilic substitution. The stability essays on PCB showed that it is most stable when stored in dry form or in ethanol. PCB showed poor stability in water, although at moderately low temperatures and higher purity the degradation rates...

  9. DOT Official County Highway Map

    Data.gov (United States)

    Minnesota Department of Natural Resources — The County Highway Map theme is a scanned and rectified version of the original MnDOT County Highway Map Series. The cultural features on some of these maps may be...

  10. Marvelous applications of quantum dots.

    Science.gov (United States)

    Cheki, M; Moslehi, M; Assadi, M

    2013-05-01

    Nanotechnology is developed to convert research, prevention, and treatment of cancer through the novel diagnostic imaging techniques and therapies. In particular, the imaging nanotechnology has gained substantial momentum in recent years. The main progress in nanotechnology has led to the production of novel fluorescent probes named quantum dots (QDs). Quantum dots develop a revolution in the molecular tagging processes within research, in vivo and in vitro studies. Due to unique physical and chemical features of QD probes, new possible techniques of early cancer detection and therapeutic management are being surveyed. Quantum dots have also dissolved many of the restrictions of organic fluorophores and are a talented option as a research tool. This review addresses on the present status of research, preclinical applications and also future visions of quantum dots.  

  11. PennDOT : fact book

    Science.gov (United States)

    2008-06-01

    PennDOT was created in 1970 when the former : Department of Highways was merged with transportation related : functions from the Departments of Revenue, : Commerce, Community Affairs and Military Affairs. With : an annual budget of about $5.4 billion...

  12. Implementace hry Dots and Boxes

    OpenAIRE

    Balko, Martin

    2010-01-01

    Title: Dots and Boxes implementation Author: Martin Balko Department: Department of Applied Mathematics Supervisor: RNDr. Ondřej Pangrác, Ph.D. Supervisor's email address: Abstract: The presented thesis deals with the analysis of a popular logical game Dots and Boxes and its generalized versions. It focuses on the different methods and algorithms of opponent's artificial intelligence. The result of the work is implementation of the generalized version of this game in w...

  13. Quantum dots in cell biology.

    Science.gov (United States)

    Barroso, Margarida M

    2011-03-01

    Quantum dots are semiconductor nanocrystals that have broad excitation spectra, narrow emission spectra, tunable emission peaks, long fluorescence lifetimes, negligible photobleaching, and ability to be conjugated to proteins, making them excellent probes for bioimaging applications. Here the author reviews the advantages and disadvantages of using quantum dots in bioimaging applications, such as single-particle tracking and fluorescence resonance energy transfer, to study receptor-mediated transport.

  14. Melanoma and satellite blue papule.

    Science.gov (United States)

    Oliveira, André; Arzberger, Edith; Massone, Cesare; Zalaudek, Iris; Fink-Puches, Regina; Hofmann-Wellenhof, Rainer

    2014-07-01

    The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slow-growing malignant melanoma was made. Simultaneously, a well-defined blue papule was seen on the proximal third of the same arm. Dermoscopy disclosed a homogeneous blue pattern. After clinical and dermoscopic correlation our differential diagnosis for this blue lesion included cutaneous melanoma metastasis, blue nevus and foreign body reaction. The patient recalled its onset 75 years ago after a grenade explosion. We also discuss the blue lesion appearance under reflectance confocal microscopy and high-definition optical coherence tomography. Histopathological examination after excision of the hyperpigmented patch and blue papule revealed a melanoma in situ and a foreign body reaction, respectively. The diagnostic evaluation of a blue lesion should always rely on the integration of all data, especially clinical and dermoscopic features. Other non-invasive techniques, like reflectance confocal microscopy and high-definition optical coherence tomography can also be important aids for its differential diagnosis.

  15. One-pot synthesis of carbon dots using two different acids and their respective unique photoluminescence property.

    Science.gov (United States)

    Loi, Elaine; Ng, Roy Wei Chao; Chang, Melissa May Fung; Fong, Jessica Fung Yee; Ng, Yann Huey; Ng, Sing Muk

    2017-02-01

    Carbon dots, a new class of nanomaterial with unique optical property and have great potential in various applications. This work demonstrated the possibility of tuning the emission wavelength of carbon dots by simply changing the acid type used during synthesis. In particular, sulfuric and phosphoric acids and a mixture of the two were used to carbonize the same starting precursor, sucrose. This resulted in the isolation of carbon dots with blue (440 nm) and green (515 nm) emission. Interestingly, the use of an acid mixture at various ratios did not shift the initial emission profile, but did obviously alter the fluorescence efficiency of the peaks. This clearly showed that acid type can be used as an alternative tool to produce carbon dots that have different emissions using the same starting precursor. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Blues fans and suicide acceptability.

    Science.gov (United States)

    Stack, S

    2000-01-01

    Research has neglected the possible impact of the blues music subculture on suicide acceptability (SA). The sad themes in the blues may attract suicidal persons and reinforce their suicidal moods and attitudes. The present study performs the first test of the thesis that associates SA with being a blues fan. It uses data on a national sample of 961 adults drawn from the General Social Survey of 1993. The results of a multivariate logistic regression analysis found that blues fans were no more accepting of suicide than nonfans. However, blues fanship was found to have substantial indirect effects on SA through its influence on such factors as lowered religiosity levels, the most important predictor of SA. Race-specific analyses found more support for the model for whites than for African Americans.

  17. Photoionization cross section in a spherical quantum dot: Effects of some parabolic confining electric potentials

    Directory of Open Access Journals (Sweden)

    M. Tshipa

    2017-12-01

    Full Text Available A theoretical investigation of the effects of spatial variation of confining electric potential on photoionization cross section (PCS in a spherical quantum dot is presented. The potential profiles considered here are the shifted parabolic potential and the inverse lateral shifted parabolic potential compared with the well-studied parabolic potential. The primary findings are that parabolic potential and the inverse lateral shifted parabolic potential blue shift the peaks of the PCS while the shifted parabolic potential causes a red shift.

  18. Exciton-mediated Raman scattering in CdS quantum dot

    Science.gov (United States)

    Guo, Xiaotong; Liu, Cuihong

    2017-09-01

    A theoretical calculation of the differential cross section (DCS) is presented for the exciton-mediated Stokes Raman scattering in CdS quantum dot within the frame work of effective mass approximation at T = 0 K. Numerical calculations reveal that the excitonic effects cause blue shifts in Raman spectroscopy. The magnitude of the Raman shift depends on the quantum confinement, the Coulomb interaction, and the incident photon energy.

  19. The Between Story: Physical and Psychic Trauma in the Poetry of Sonia Sanchez and Lucille Clifton

    Directory of Open Access Journals (Sweden)

    Bazemore, Chanae D.

    2013-12-01

    Full Text Available Rhetorical choices used by Black women poets makes their work a militant force in the theoretical war against racist and sexist oppression. Research on trauma and testimony supports a breakdown of the person’s or character’s sudden brush with death –a moment that will never be fully realized, however it is at the center of explicating the rhetorical signs of trauma. Through a reading of Sonia Sanchez’s poems “Wounded in the House of a Friend” (Sanchez, 1995: 5, “Poem for Some Women” (Sanchez, 1995: 72, “Eyewitness: Case No. 3456” (Sanchez, 1995: 70, and “Poem at Thirty” (Sanchez, 1985: 4, with Lucille Clifton’s “My Friends” (Clifton, 1987: 147, “Shapeshifter Poems” (Clifton, 2000: 52, and “Song at Midnight” (Clifton, 1993: 24, my analysis will trace how traumatic wounding constitutes a psychic wound. It then applies the racialized and gendered reading of the subjects in the poem (insidious trauma, and how time and space relates to the subjects, space, and silences (traumatic realism. With the use trauma theory, I will illustrate how Sanchez and Clifton’s aesthetic forms adapted the militancy of the Black Arts Movement to address the silenced voices. In particular, the silenced voices of subjects continually subsumed beneath the phallocentric undertones challenged by Black feminist discourse, art, and poetry will be addressed.Las opciones retóricas utilizadas por las poetas negras hacen de su trabajo una herramienta militante en la batalla teórica contra la opresión racista y sexista. Investigar sobre el trauma y el testimonio conlleva una crisis de la persona o el carácter, repentinamente teñidos con la muerte –un momento nunca por entero realizado–, que sin embargo está en el centro de la explicación de los signos retóricos del trauma. Mediante la lectura de los poemas de Sonia Sánchez “Wounded in the House of a Friend” (Sanchez, 1995: 5, “Poem for Some Women” (Sanchez, 1995: 72,

  20. True blue football fan: tattoo reaction confined to blue pigment.

    Science.gov (United States)

    Yoong, Corinne; Vun, Yin Yin; Spelman, Lynda; Muir, James

    2010-02-01

    A tattoo reaction which appeared solely on the blue pigment of a 6-month old red and blue football club tattoo of an ardent fan was investigated. The patient was otherwise asymptomatic and no other abnormality was detected on full physical examination. Histology revealed a florid sarcoidal granuloma reaction to blue pigment. Preliminary investigations for systemic sarcoidosis did not reveal any abnormality. The tattoo reaction flattened clinically with the institution of a short course of topical mometasone furoate 0.1% ointment and as the subject remained asymptomatic, close surveillance for the development of systemic sarcoidosis is to continue. The possibility of delayed type hypersensitivity is discussed.

  1. Stability of quantum dots in live cells

    Science.gov (United States)

    Zhu, Zheng-Jiang; Yeh, Yi-Cheun; Tang, Rui; Yan, Bo; Tamayo, Joshua; Vachet, Richard W.; Rotello, Vincent M.

    2011-12-01

    Quantum dots are highly fluorescent and photostable, making them excellent tools for imaging. When using these quantum dots in cells and animals, however, intracellular biothiols (such as glutathione and cysteine) can degrade the quantum dot monolayer, compromising function. Here, we describe a label-free method to quantify the intracellular stability of monolayers on quantum dot surfaces that couples laser desorption/ionization mass spectrometry with inductively coupled plasma mass spectrometry. Using this new approach we have demonstrated that quantum dot monolayer stability is correlated with both quantum dot particle size and monolayer structure, with appropriate choice of both particle size and ligand structure required for intracellular stability.

  2. Imaging and Manipulating Energy Transfer Among Quantum Dots at Individual Dot Resolution.

    Science.gov (United States)

    Nguyen, Duc; Nguyen, Huy A; Lyding, Joseph W; Gruebele, Martin

    2017-06-27

    Many processes of interest in quantum dots involve charge or energy transfer from one dot to another. Energy transfer in films of quantum dots as well as between linked quantum dots has been demonstrated by luminescence shift, and the ultrafast time-dependence of energy transfer processes has been resolved. Bandgap variation among dots (energy disorder) and dot separation are known to play an important role in how energy diffuses. Thus, it would be very useful if energy transfer could be visualized directly on a dot-by-dot basis among small clusters or within films of quantum dots. To that effect, we report single molecule optical absorption detected by scanning tunneling microscopy (SMA-STM) to image energy pooling from donor into acceptor dots on a dot-by-dot basis. We show that we can manipulate groups of quantum dots by pruning away the dominant acceptor dot, and switching the energy transfer path to a different acceptor dot. Our experimental data agrees well with a simple Monte Carlo lattice model of energy transfer, similar to models in the literature, in which excitation energy is transferred preferentially from dots with a larger bandgap to dots with a smaller bandgap.

  3. Growth and characterization of InP ringlike quantum-dot molecules grown by solid-source molecular beam epitaxy.

    Science.gov (United States)

    Jevasuwan, Wipakorn; Boonpeng, Poonyasiri; Panyakeow, Somsak; Ratanathammaphan, Somchai

    2010-11-01

    In this paper, we have studied the fabrication of InP ringlike quantum-dot molecules on GaAs(001) substrate grown by solid-source molecular beam epitaxy using droplet epitaxy technique and the effect of In deposition rate on the physical and optical properties of InP ringlike quantum-dot molecules. The In deposition rate is varied from 0.2 ML/s to 0.4, 0.8 and 1.6 ML/s. The surface morphology and cross-section were examined by ex-situ atomic force microscope and transmission electron microscope, respectively. The increasing of In deposition rate results in the decreasing of outer and inner diameters of InP ringlike quantum-dot molecules and height of InP quantum dots but increases the InP quantum dot and ringlike quantum-dot molecule densities. The photoluminescence peaks of InP ringlike quantum-dot molecules are blue-shifted and FWHM is narrower when In deposition rate is bigger.

  4. THE SUBJECTIVAL CONTENT OF IMAGES “SUCCESSFUL MAN” AND “SUCCESSFUL WOMAN” AS A FACTOR OF PSYCHIC ADJUSTMENT OF WOMEN IN INVOLUNTARY UNEMPLOYMENT SITUATION

    Directory of Open Access Journals (Sweden)

    Ольга Геннадьевна Лопухова

    2013-09-01

    Full Text Available Purpose of the study is investigation of correlation between a content of gender appearance of image “successful person” and parameters of psychic and social adjustment of women belonging to different generations.Methodology.  Subjective image “successful person” means a stable and possibly gender differentiated element of “Ideal Me” images system. It includes cognitive component (conscious and verbalization representations of typical description of successful person, and affective component (positive or negative positions in regards to image “successful person”. We have compared results of survey and valuation of 265 women belonging to different generations and staying in different social situations: involuntary unemployment situation, employment and getting professional education. Subjective and projective methods were used in survey of cognitive and affective components of “successful person” image. Valuation of psychic adjustment based on parameters of internal conflict in comparison with manifestations of anxiety, frustration, aggression, rigidity, neurotic. Data analysis used parametric and nonparametric methods, including ANOVA/MANOVA.Results. It has been discovered that level of psychic adjustment of women depends much more on proper integration of subjective “successful person” image content with individual features of self-conception than on objective “social status” (being in involuntary unemployment situation.Practical implications are psychology consulting and correction of social or psychic unadjustment.DOI: http://dx.doi.org/10.12731/2218-7405-2013-6-41

  5. The status of psychic reality in adolescence. An adult female patient's quasi-adolescent material and the analyst's counter transference response.

    Science.gov (United States)

    Eiguer, A

    1996-12-01

    The author holds that the crisis of adolescence is in fact one of psychic reality, its elements being loss of boundaries, externalisation and the involvement of a third party. In this view, it is essential to conceive of adolescence differently from adulthood, in that, for example, an adolescent's acting out may not be solely a matter of regression but to a considerable extent a consequence of his or her physical development. It is noted that the boundaries between psychic and material reality are fluid throughout life and that adolescents crave identificatory models. The author stresses the importance of the psychic reality of the other in the adolescent's crisis. After considering various views, including those of Freud, on psychic reality and the crises of adolescence, he illustrates his thesis by the clinical example of two adolescent episodes of perversion forming part of an adult female patient's material. In the author's view, these instances of acting out had helped the patient to regain her auto-erotic capacity in the pleasure of fantasy life. He considers that a mutative interpretation must touch upon the primal fantasy and therefore involve the entire person of the analyst in the transference.

  6. Analysis of the rate of improvement of specific psychic and somatic symptoms of general anxiety disorder during long-term treatment with venlafaxine ER.

    Science.gov (United States)

    Stahl, Stephen M; Ahmed, Saeeduddin; Haudiquet, Vincent

    2007-09-01

    Generalized anxiety disorder (GAD) is a chronic illness with psychic and somatic symptoms that do not respond uniformly in the first weeks of treatment. A post-hoc analysis of pooled data from five placebo-controlled, double-blind, randomized studies in non-depressed GAD patients treated with venlafaxine extended release (ER) or placebo was performed to determine the temporal response of psychic and somatic symptoms to treatment over 8 weeks. Two of the studies included extension phases of up to 6 months, the results of which were also analyzed here. The earliest symptoms to respond included both psychic symptoms (anxious mood, tension, behavior at interview) and somatic muscular, cardiovascular, and respiratory symptoms. The last symptoms to respond included the psychic symptoms of insomnia and fear and the somatic sensory, gastrointestinal and autonomic symptoms, perhaps in part because of drug-related side effects. Continuing treatment beyond 8 weeks in venlafaxine ER responders for up to 6 months of total treatment results not only in additional improvement in early-responding symptoms, but also in the improvement of late-responding symptoms, perhaps due in part to the development of tolerance to antidepressant side effects. Serious consideration should be given to maintaining partial responders to venlafaxine ER treatment on the same treatment for > or = 3-6 months.

  7. Inter-dot coupling effects on transport through correlated parallel ...

    Indian Academy of Sciences (India)

    The effect of inter-dot tunnelling on transport properties has been explored. Results, in intermediate inter-dot coupling regime show signatures of merger of two dots to form a single composite dot and in strong coupling regime the behaviour of the system resembles the two decoupled dots. Keywords. Coupled quantum dots ...

  8. [Work-related stress according to the Demand-Control Model and Minor Psychic Disorder in nursing workers].

    Science.gov (United States)

    Urbanetto, Janete de Souza; Magalhães, Maria Cristina Cademartori; Maciel, Vanessa Oreda; Sant'Anna, Viviane Massena; Gustavo, Andréia da Silva; Poli-de-Figueiredo, Carlos Eduardo; Magnago, Tânia Solange Bosi de Souza

    2013-10-01

    This was a cross-sectional study that aimed to assess the association between work-related stress according to the Demand-Control Model, and the occurrence of Minor Psychic Disorder (MPD) in nursing workers. The participants were 335 professionals, out of which 245 were nursing technicians, aged predominantly between 20 and 40 years. Data were collected using the Job Stress Scale and the Self-Reporting Questionnaire-20. The analysis was performed using descriptive and analytical statistics. The prevalence of suspected MPD was 20.6%. Workers classified in the quadrants active job and high strain of the Demand-Control Model presented higher potential for developing MPD compared with those classified in the quadrant low strain. In conclusion, stress affects the mental health of workers and the aspects related to high psychological demands and high control still require further insight in order to understand their influence on the disease processes of nursing workers.

  9. Work-related stress according to the demand-control model and minor psychic disorders in nursing workers

    Directory of Open Access Journals (Sweden)

    Janete de Souza Urbanetto

    2013-10-01

    Full Text Available This was a cross-sectional study that aimed to assess the association between work-related stress according to the Demand-Control Model, and the occurrence of Minor Psychic Disorder (MPD in nursing workers. The participants were 335 professionals, out of which 245 were nursing technicians, aged predominantly between 20 and 40 years. Data were collected using the Job Stress Scale and the Self-Reporting Questionnaire-20. The analysis was performed using descriptive and analytical statistics. The prevalence of suspected MPD was 20.6%. Workers classified in the quadrants active job and high strain of the Demand-Control Model presented higher potential for developing MPD compared with those classified in the quadrant low strain. In conclusion, stress affects the mental health of workers and the aspects related to high psychological demands and high control still require further insight in order to understand their influence on the disease processes of nursing workers.

  10. Occupational hazards in hospitals: accidents, radiation, exposure to noxious chemicals, drug addiction and psychic problems, and assault.

    Science.gov (United States)

    Gestal, J J

    1987-01-01

    Except for infectious diseases all the main occupational hazards affecting health workers are reviewed: accidents (explosions, fires, electrical accidents, and other sources of injury); radiation (stochastic and non-stochastic effects, protective measures, and personnel most at risk); exposure to noxious chemicals, whose effects may be either local (allergic eczema) or generalised (cancer, mutations), particular attention being paid to the hazards presented by formol, ethylene oxide, cytostatics, and anaesthetic gases; drug addiction (which is more common among health workers than the general population) and psychic problems associated with promotion, shift work, and emotional stress; and assault (various types of assault suffered by health workers, its causes, and the characterisation of the most aggressive patients). PMID:3307896

  11. Transport through graphene quantum dots

    Science.gov (United States)

    Güttinger, J.; Molitor, F.; Stampfer, C.; Schnez, S.; Jacobsen, A.; Dröscher, S.; Ihn, T.; Ensslin, K.

    2012-12-01

    We review transport experiments on graphene quantum dots and narrow graphene constrictions. In a quantum dot, electrons are confined in all lateral dimensions, offering the possibility for detailed investigation and controlled manipulation of individual quantum systems. The recently isolated two-dimensional carbon allotrope graphene is an interesting host to study quantum phenomena, due to its novel electronic properties and the expected weak interaction of the electron spin with the material. Graphene quantum dots are fabricated by etching mono-layer flakes into small islands (diameter 60-350 nm) with narrow connections to contacts (width 20-75 nm), serving as tunneling barriers for transport spectroscopy. Electron confinement in graphene quantum dots is observed by measuring Coulomb blockade and transport through excited states, a manifestation of quantum confinement. Measurements in a magnetic field perpendicular to the sample plane allowed to identify the regime with only a few charge carriers in the dot (electron-hole transition), and the crossover to the formation of the graphene specific zero-energy Landau level at high fields. After rotation of the sample into parallel magnetic field orientation, Zeeman spin splitting with a g-factor of g ≈ 2 is measured. The filling sequence of subsequent spin states is similar to what was found in GaAs and related to the non-negligible influence of exchange interactions among the electrons.

  12. Ecology of blue straggler stars

    CERN Document Server

    Carraro, Giovanni; Beccari, Giacomo

    2015-01-01

    The existence of blue straggler stars, which appear younger, hotter, and more massive than their siblings, is at odds with a simple picture of stellar evolution. Such stars should have exhausted their nuclear fuel and evolved long ago to become cooling white dwarfs. They are found to exist in globular clusters, open clusters, dwarf spheroidal galaxies of the Local Group, OB associations and as field stars. This book summarises the many advances in observational and theoretical work dedicated to blue straggler stars. Carefully edited extended contributions by well-known experts in the field cover all the relevant aspects of blue straggler stars research: Observations of blue straggler stars in their various environments; Binary stars and formation channels; Dynamics of globular clusters; Interpretation of observational data and comparison with models. The book also offers an introductory chapter on stellar evolution written by the editors of the book.

  13. Karner Blue Butterfly Recovery Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This recovery plan has been prepared by the Karner Blue Butterfly Recovery Team under the leadership of Dr. David Andow, University of Minnesota-St. Paul. Dr. John...

  14. Optical absorption, photoluminescence and structural analysis of CdS quantum dots in weak confinement

    Science.gov (United States)

    Mishra, Rakesh K.; Vedeshwar, A. G.; Tandon, R. P.

    2014-02-01

    The diffusion-controlled growth of CdS quantum dots (QDs) dispersed in a silicate glass matrix was investigated. It was found that the size of CdS QDs can be controlled by either heat treatment at various temperatures for a fixed duration or varying times at a constant temperature. Pastel yellow colored glass samples were obtained due to the presence of CdS petite crystals. X-ray diffraction (XRD) was used for determining the average dot size which varied from 3.8 to 30 nm. The typical quantum confinement effect was clearly observed from the blue shift measured in the optical absorption edge with decreasing dot size in the absorption spectroscopy. The band gap of CdS QDs ranges from 2.41 to 2.82 eV. Measured photoluminescence (PL) at an excitation wavelength of 350 nm showed the red shift of emission wavelength with increasing thermal treatment time and temperature in agreement with the increasing dot sizes. The half-width of PL spectra seems to indicate qualitatively the size distribution of dots and is consistent with the treatment parameters.

  15. Synthesis of strongly fluorescent graphene quantum dots by cage-opening buckminsterfullerene.

    Science.gov (United States)

    Chua, Chun Kiang; Sofer, Zdeněk; Šimek, Petr; Jankovský, Ondřej; Klímová, Kateřina; Bakardjieva, Snejana; Hrdličková Kučková, Štěpánka; Pumera, Martin

    2015-03-24

    Graphene quantum dots is a class of graphene nanomaterials with exceptional luminescence properties. Precise dimension control of graphene quantum dots produced by chemical synthesis methods is currently difficult to achieve and usually provides a range of sizes from 3 to 25 nm. In this work, fullerene C60 is used as starting material, due to its well-defined dimension, to produce very small graphene quantum dots (∼2-3 nm). Treatment of fullerene C60 with a mixture of strong acid and chemical oxidant induced the oxidation, cage-opening, and fragmentation processes of fullerene C60. The synthesized quantum dots were characterized and supported by LDI-TOF MS, TEM, XRD, XPS, AFM, STM, FTIR, DLS, Raman spectroscopy, and luminescence analyses. The quantum dots remained fully dispersed in aqueous suspension and exhibited strong luminescence properties, with the highest intensity at 460 nm under a 340 nm excitation wavelength. Further chemical treatments with hydrazine hydrate and hydroxylamine resulted in red- and blue-shift of the luminescence, respectively.

  16. Ultrafast spectroscopy of quantum dots

    CERN Document Server

    Foo, E

    2001-01-01

    exchange-correlation interactions among the confined carriers inside the dots are suggested to be responsible. A density functional calculation for BGR of the ground state transition shows good agreement with our experimental results, especially in the high dot occupancy regime. Many-particle state scattering gives rise to large homogeneous spectral broadening of the PL peaks, from which an intradot relaxation time approx 300 fs is estimated. This observation supports the results obtained by direct excitation of carriers within the QDs. Femtosecond time-resolved photoluminescence measured by frequency up-conversion has been used to investigate carrier dynamics in InAs/GaAs self-assembled quantum dots (QDs). Our results reveal ultrafast carrier relaxation and sequential state filling. Carrier relaxation is proposed to occur by Auger-type processes, and the sequential state filling suggests that intradot relaxation is much faster than carrier capture from the InAs wetting layer. Measurements obtained by direct ...

  17. Quantum-dot emitters in photonic nanostructures

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher; Stobbe, Søren; Lodahl, Peter

    2010-01-01

    The spontaneous emission from self-assembled semiconductor quantum dots is strongly influenced by the environment in which they are placed. This can be used to determine fundamental optical properties of the quantum dots as well as to manipulate and control the quantum-dot emission itself....

  18. Origin of tunable photoluminescence from graphene quantum dots synthesized via pulsed laser ablation.

    Science.gov (United States)

    Santiago, S R M; Lin, T N; Yuan, C T; Shen, J L; Huang, H Y; Lin, C A J

    2016-08-10

    A one-step synthesis of graphene quantum dots (GQDs) has been implemented using pulsed laser ablation (PLA) with carboxyl-functionalized multiwalled carbon nanotubes (MWCNTs). The synthesized GQDs with an average size smaller than 3 nm were obtained by the fragmentation of MWCNTs via oxidative cutting. The GQDs can generate tunable photoluminescence (PL) ranging from green to blue by controlling the PLA time. The PL spectrum (decay time) of the green GQDs remains unchanged under different excitation energies (emission energies), while that of the blue GQDs correlates with the excitation energy (emission energy). On the basis of the pH and temperature dependence of PL, we suggest that the localized intrinsic states associated with the sp(2) nanodomains and delocalized extrinsic states embedded on the GQD surface are responsible for blue and green emission in GQDs, respectively.

  19. Wavelength-tunable photoluminescence of ZnSe quantum dot micelles synthesized by femtosecond laser ablation in microfluidics

    Science.gov (United States)

    Yang, Chao; Feng, Guoying; Wang, Shutong; Dai, Jiangyun; Zhang, Yuqin; Zhou, Shouhuan

    2017-09-01

    Aqueous ZnSe quantum dots were synthesized by femtosecond laser ablation in microfluidics (FLAM). Hyperbranched polyethylenimine (PEI) was used to form quantum dot micelles which exhibited wavelength-tunable photoluminescence of bright visible light with the variation of pH values. The emission was attributed to the radiative deep levels introduced by the defect states. The emission peak center exhibited a blue shift as much as 25 nm to the shorter band. A possible band gap expansion mechanism for the photoluminescence wavelength tunability was discussed.

  20. A visible-light-driven composite photocatalyst of TiO2 nanotube arrays and graphene quantum dots

    Directory of Open Access Journals (Sweden)

    Donald K. L. Chan

    2014-05-01

    Full Text Available TiO2 nanotube arrays are well-known efficient UV-driven photocatalysts. The incorporation of graphene quantum dots could extend the photo-response of the nanotubes to the visible-light range. Graphene quantum dot-sensitized TiO2 nanotube arrays were synthesized by covalently coupling these two materials. The product was characterized by Fourier-transform infrared spectrometry (FTIR, scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffraction (XRD, thermogravimetric analysis (TGA and UV–vis absorption spectroscopy. The product exhibited high photocatalytic performance in the photodegradation of methylene blue and enhanced photocurrent under visible light irradiation.

  1. Spin storage in quantum dot ensembles and single quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Heiss, Dominik

    2009-10-15

    This thesis deals with the investigation of spin relaxation of electrons and holes in small ensembles of self-assembled quantum dots using optical techniques. Furthermore, a method to detect the spin orientation in a single quantum dot was developed in the framework of this thesis. A spin storage device was used to optically generate oriented electron spins in small frequency selected quantum dot ensembles using circularly polarized optical excitation. The spin orientation can be determined by the polarization of the time delayed electroluminescence signal generated by the device after a continuously variable storage time. The degree of spin polarized initialization was found to be limited to 0.6 at high magnetic fields, where anisotropic effects are compensated. The spin relaxation was directly measured as a function of magnetic field, lattice temperature and s-shell transition energy of the quantum dot by varying the spin storage time up to 30 ms. Very long spin lifetimes are obtained with a lower limit of T{sub 1}=20 ms at B=4 T and T=1 K. A strong magnetic field dependence T{sub 1}{proportional_to}B{sup -5} has been observed for low temperatures of T=1 K which weakens as the temperature is increased. In addition, the temperature dependence has been determined with T{sub 1}{proportional_to}T{sup -1}. The characteristic dependencies on magnetic field and temperature lead to the identification of the spin relaxation mechanism, which is governed by spin-orbit coupling and mediated by single phonon scattering. This finding is qualitatively supported by the energy dependent measurements. The investigations were extended to a modified device design that enabled studying the spin relaxation dynamics of heavy holes in self-assembled quantum dots. The measurements show a polarization memory effect for holes with up to 0.1 degree of polarization. Furthermore, investigations of the time dynamics of the hole spin relaxation reveal surprisingly long lifetimes T{sub 1}{sup h

  2. Evaluation of Code Blue Implementation Outcomes

    OpenAIRE

    Bengü Özütürk; Nalan Muhammedoğlu; Emel Dal; Berna Çalışkan

    2015-01-01

    Aim: In this study, we aimed to emphasize the importance of Code Blue implementation and to determine deficiencies in this regard. Methods: After obtaining the ethics committee approval, 225 patient’s code blue call data between 2012 and 2014 January were retrospectively analyzed. Age and gender of the patients, date and time of the call and the clinics giving Code Blue, the time needed for the Code Blue team to arrive, the rates of false Code Blue calls, reasons for Code...

  3. High color rendering index white light emitting diodes fabricated from a combination of carbon dots and zinc copper indium sulfide quantum dots

    Science.gov (United States)

    Sun, Chun; Zhang, Yu; Wang, Yu; Liu, Wenyan; Kalytchuk, Sergii; Kershaw, Stephen V.; Zhang, Tieqiang; Zhang, Xiaoyu; Zhao, Jun; Yu, William W.; Rogach, Andrey L.

    2014-06-01

    In a line with most recent trends in developing non-toxic fluorescent nanomaterials, we combined blue emissive carbon dots with green and red emissive zinc copper indium sulfide (ZCIS) core/shell quantum dots (QDs) to achieve white light-emitting diodes (WLEDs) with a high color rendering index of 93. This indicates that ZCIS QDs, with their broad emission bands, can be employed to effectively make up the emission of carbon dots in the yellow and red regions to produce WLEDs in the wide region of color temperature by tuning the volume ratio of these constituting luminophores. Their electroluminescence characteristics including color rendering index, Commission Internationale de l'Eclairage (CIE) color coordinates, and color temperatures were evaluated as a function of forward current. The CIE-1931 chromaticity coordinates of the as-prepared WLEDs, exhibiting good stability, were slightly shifted from (0.321, 0.312) at 10 mA to (0.351, 0.322) at 30 mA, which was mainly caused by the different thermal quenching coefficients of carbon dots and ZCIS QDs.

  4. Hyperdense dots mimicking microcalcifications : Mammographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nam Hyeon; Park, Jeong Mi; Goo, Hyun Woo; Bang, Sun Woo [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    1996-12-01

    To differentiate fine hyperdense dots mimicking microcalcifications from true microcalcifications on mammography. Mammograms showing hyperdense dots in ten patients (mean age, 59 years) were evaluated. Two radiologists were asked to differentiate with the naked eye the hyperdense dots seen on ten mammograms and proven microcalcifications seen on ten mammograms. Densitometry was also performed for all lesions and the contrast index was calculated. The shape and distribution of the hyperdense dots were evaluated and enquires were made regarding any history of breast disease and corresponding treatment. Biopsies were performed for two patients with hyperdense dots. Two radiologists made correct diagnoses in 19/20 cases(95%). The contrast index was 0.10-0.88 (mean 0.58) for hyperdense dots and 0.02-0.45 (mean 0.17) for true microcalcifications. The hyperdense dots were finer and homogeneously rounder than the microcalcifications. Distribution of the hyperdense dots was more superficial in subcutaneous fat (seven cases) and subareolar area (six cases). All ten patients with hyperdense dots had history of mastitis and abscesses and had been treated by open drainage (six cases) and/or folk remedy (four cases). In eight patients, herb patches had been attached. Biopsies of hyperdense dots did not show any microcalcification or evidence of malignancy. These hyperdense dots were seen mainly in older patients. Their characteristic density, shape, distribution and clinical history makes differential diagnosis from true microcalcifications easy and could reduce unnecessary diagnostic procedures such as surgical biopsy.

  5. Optophononics with Coupled Quantum Dots

    Science.gov (United States)

    2014-02-18

    single InAs/GaAs quantum dots. Phys. Rev. B 68, 233301 (2003). 9. Bennemann, K.-H. & Ketterson, J. B. (eds), Superconductivity : Conventional and...superlattices. Science 338, 935–939 (2012). 17. Kim, J.-H. et al. Coherent phonons in carbon nanotubes and graphene . Chem. Phys. 413, 55–80 (2013). 18

  6. DOT strategies versus orbiter strategies

    NARCIS (Netherlands)

    Rutten, R.J.

    2001-01-01

    The Dutch Open Telescope is a high-resolution solar imager coming on-line at La Palma. The definition of the DOT science niche, strategies, and requirements resemble Solar Orbiter considerations and deliberations. I discuss the latter in the light of the former, and claim that multi-line observation

  7. Luminescent Surface Quaternized Carbon Dots

    KAUST Repository

    Bourlinos, Athanasios B.

    2012-01-10

    Thermal oxidation of a salt precursor made from the acid base combination of tris(hydroxymethyl)aminomethane and betaine hydrochloride results in light-emitting surface quaternized carbon dots that are water-dispersible, display anion exchange properties, and exhibit uniform size/surface charge. © 2011 American Chemical Society.

  8. Polymer-coated quantum dots

    NARCIS (Netherlands)

    Tomczak, N.; Liu, Rongrong; Vancso, Gyula J.

    2013-01-01

    Quantum Dots (QDs) are semiconductor nanocrystals with distinct photophysical properties finding applications in biology, biosensing, and optoelectronics. Polymeric coatings of QDs are used primarily to provide long-term colloidal stability to QDs dispersed in solutions and also as a source of

  9. Nuclear Spins in Quantum Dots

    NARCIS (Netherlands)

    Erlingsson, S.I.

    2003-01-01

    The main theme of this thesis is the hyperfine interaction between the many lattice nuclear spins and electron spins localized in GaAs quantum dots. This interaction is an intrinsic property of the material. Despite the fact that this interaction is rather weak, it can, as shown in this thesis,

  10. Silicon quantum dots: surface matters

    NARCIS (Netherlands)

    Dohnalová, K.; Gregorkiewicz, T.; Kůsová, K.

    2014-01-01

    Silicon quantum dots (SiQDs) hold great promise for many future technologies. Silicon is already at the core of photovoltaics and microelectronics, and SiQDs are capable of efficient light emission and amplification. This is crucial for the development of the next technological frontiers—silicon

  11. Eco-friendly intracellular biosynthesis of CdS quantum dots without changing Escherichia coli's antibiotic resistance.

    Science.gov (United States)

    Yan, Zheng-Yu; Du, Qing-Qing; Qian, Jing; Wan, Dong-Yu; Wu, Sheng-Mei

    2017-01-01

    In the paper, a green and efficient biosynthetical technique was reported for preparing cadmium sulfide (CdS) quantum dots, in which Escherichia coli (E. coli) was chosen as a biomatrix. Fluorescence emission spectra and fluorescent microscopic photographs revealed that as-produced CdS quantum dots had an optimum fluorescence emission peak located at 470nm and emitted a blue-green fluorescence under ultraviolet excitation. After extracted from bacterial cells and located the nanocrystals' foci in vivo, the CdS quantum dots showed a uniform size distribution by transmission electron microscope. Through the systematical investigation of the biosynthetic conditions, including culture medium replacement, input time point of cadmium source, working concentrations of raw inorganic ions, and co-cultured time spans of bacteria and metal ions in the bio-manufacture, the results revealed that CdS quantum dots with the strongest fluorescence emission were successfully prepared when E. coli cells were in stationary phase, with the replacement of culture medium and following the incubation with 1.0×10-3mol/L cadmium source for 2 days. Results of antimicrobial susceptibility testing indicated that the sensitivities to eight types of antibiotics of E. coli were barely changed before and after CdS quantum dots were prepared in the mild temperature environment, though a slight fall of antibiotic resistance could be observed, suggesting hinted the proposed technique of producing quantum dots is a promising environmentally low-risk protocol. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Fluorescent labeling of cells and biomolecules with nanocrystal quantum dots

    Science.gov (United States)

    Hoshino, Akiyoshi; Fujioka, Kouki; Suga, Masakazu; Sasaki, Yu F.; Ohta, Toshihiro; Yasuhara, Masato; Dohi, Taeko; Suzuki, Kazuo; Yamamoto, Kenji

    2005-04-01

    Fluorescent nanoparticles, such as nanocrystal quantum dots (QDs), novel nanometer-size probes and have the potential to be used as easy imaging tool for molecular biology and bioimaging including medical applications, since some nanocrystals emit higher and far longer fluorescence than conventional organic probes. QDs are now becoming widely used in biotechnology and medical applications. QDs have several advantages over organic fluorophores with regard to high luminescence, stability against photobleaching, and a range of fluorescence wavelengths from blue to infrared depending on the particle size. In this review, we reported labeling of some kinds of immune cells and biomolecules with several QDs coated with hydrophilic carboxyl/amine groups, and reported that we could image the circulation of mouse lymphocytes in vivo by QDs. In addition, we also reported here about the cytotoxicity of these nanocrystals.

  13. Multi-Color Single Particle Tracking with Quantum Dots

    DEFF Research Database (Denmark)

    Christensen, Eva Arnspang; Brewer, J. R.; Lagerholm, B. C.

    2012-01-01

    Quantum dots (QDs) have long promised to revolutionize fluorescence detection to include even applications requiring simultaneous multi-species detection at single molecule sensitivity. Despite the early promise, the unique optical properties of QDs have not yet been fully exploited in e. g....... multiplex single molecule sensitivity applications such as single particle tracking (SPT). In order to fully optimize single molecule multiplex application with QDs, we have in this work performed a comprehensive quantitative investigation of the fluorescence intensities, fluorescence intensity fluctuations...... further show that there is only a small size advantage in using blue-shifted QDs in biological applications because of the additional size of the water-stabilizing surface coat. Extending previous work, we finally also show that parallel four color multicolor (MC)-SPT with QDs is possible at an image...

  14. Bandgap engineering of coal-derived graphene quantum dots.

    Science.gov (United States)

    Ye, Ruquan; Peng, Zhiwei; Metzger, Andrew; Lin, Jian; Mann, Jason A; Huang, Kewei; Xiang, Changsheng; Fan, Xiujun; Samuel, Errol L G; Alemany, Lawrence B; Martí, Angel A; Tour, James M

    2015-04-01

    Bandgaps of photoluminescent graphene quantum dots (GQDs) synthesized from anthracite have been engineered by controlling the size of GQDs in two ways: either chemical oxidative treatment and separation by cross-flow ultrafiltration, or by a facile one-step chemical synthesis using successively higher temperatures to render smaller GQDs. Using these methods, GQDs were synthesized with tailored sizes and bandgaps. The GQDs emit light from blue-green (2.9 eV) to orange-red (2.05 eV), depending on size, functionalities and defects. These findings provide a deeper insight into the nature of coal-derived GQDs and demonstrate a scalable method for production of GQDs with the desired bandgaps.

  15. Potassium doping: Tuning the optical properties of graphene quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Fuli; Li, Xueming, E-mail: lxmscience@163.com; Lu, Chaoyu [Solar Energy Research Institute, Yunnan Normal University, Kunming, 650092 (China); Tang, Libin, E-mail: scitang@163.com [Kunming Institute of Physics, Kunming 650223 (China); Lai, Sin Ki; Lau, Shu Ping [Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong SAR (China)

    2016-07-15

    Doping with hetero-atoms is an effective way to tune the properties of graphene quantum dots (GQDs). Here, potassium-doped GQDs (K-GQDs) are synthesized by a one-pot hydrothermal treatment of sucrose and potassium hydroxide solution. Optical properties of the GQDs are altered as a result of K-doping. The absorption peaks exhibit a blue shift. Multiple photoluminescence (PL) peaks are observed as the excitation wavelength is varied from 380 nm to 620 nm. New energy levels are introduced into the K-GQDs and provide alternative electron transition pathways. The maximum PL intensity of the K-GQDs is obtained at an excitation wavelength of 480 nm which is distinct from the undoped GQDs (375 nm). The strong PL of the K-GQDs at the longer emission wavelengths is expected to make K-GQDs more suitable for bioimaging and optoelectronic applications.

  16. Bonney's blue cystitis: a warning.

    Science.gov (United States)

    Christmas, T J; Chapple, C R; Payne, S D; Milroy, E J; Warwick, R T

    1989-03-01

    The instillation of diluted Bonney's blue into the bladder during gynaecological operations has been quite common practice over the last 50 years. Bonney's blue is composed of a 1:1 mixture of brilliant green and crystal violet dissolved in ethanol (90%) or industrial methylated spirit. Before insertion into the bladder this solution must be diluted with water to a 0.5% solution. Failure to do this will result in a severe inflammatory reaction within the bladder. The degree of resultant damage depends upon the duration of exposure. Persistent pain is a feature of this condition, although the other symptoms (frequency and urgency) may settle in time. Two cases of chemical cystitis resulting from the use of undiluted Bonney's blue are described to illustrate the possible consequences. Both patients were awarded 6-figure sums as compensation.

  17. Why Do Proteins Glow Blue?

    CERN Document Server

    Sarkar, Sohini; Hazra, Partha; Mandal, Pankaj

    2014-01-01

    Recent literatures reported blue-green emission from amyloid fibril as exclusive signature of fibril formation. This unusual visible luminescence is regularly used to monitor fibril growth. Blue-green emission has also been observed in crystalline protein and in solution. However, the origin of this emission is not known exactly. Our spectroscopic study of serum proteins reveals that the blue-green emission is a property of protein monomer. Evidences suggest that semiconductor-like band structure of proteins with the optical band-gap in the visible region is possibly the origin of this phenomenon. We show here that the band structure of proteins is primarily the result of electron delocalization through the peptide chain, rather than through the hydrogen bond network in secondary structure.

  18. Agminated blue nevus - Case report*

    Science.gov (United States)

    Lisboa, Alice Paixão; Silvestre, Keline Jácome; Pedreira, Renata Leite; Alves, Natália Ribeiro de Magalhães; Obadia, Daniel Lago; Azulay-Abulafia, Luna

    2016-01-01

    Blue nevi are benign melanocytic lesions located in the deeper reticular dermis, consequence of failure of melanocytic migration into the dermal-epidermal junction from the neural crest. Lesions are usually asymptomatic and solitary, but may present in a multiple or agminated (grouped) pattern. The agminated subtype is formed when bluish-pigmented lesions cluster together in a well-defined area. Lesions can be flat or raised. We report the case of a patient who presented multiple bluish macules (1-3 mm in diameter) grouped on the left upper back. Dermoscopy and anatomic pathological examination were consistent with blue nevus. PMID:27828645

  19. Baby blues: identification and intervention.

    Science.gov (United States)

    Hansen, C H

    1990-01-01

    Transitory postpartum depressive syndrome or baby blues affects up to 80% of all newly delivered women. Baby Blues is so common it may be considered normal. While one of the more mild forms of depression after child birth, it can still be disruptive to the family unit. Both physiological and psychosocial factors contribute to the syndrome. Appropriate nursing assessment and intervention throughout the childbearing cycle can be very beneficial in helping families to understand and cope with the problem, as well as help prevent more serious depressive syndromes.

  20. Laponite blue: dissolving the insoluble.

    Science.gov (United States)

    Lezhnina, Marina M; Grewe, Tobias; Stoehr, Hardo; Kynast, Ulrich

    2012-10-15

    The neutral organic dye indigo forms an inorganic-organic hybrid material with nanoclays (see picture; blue circles on disks symbolizing indigo, spheres indicating liberated cations) and can thus be transferred into aqueous solution. Solids recovered from these solutions resemble the ancient Maya Blue pigment. The method can also be applied to other hydrophobic species and may open the gate for novel solution chemistry, including photonic and catalytic applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. [The classifying criteria for the evaluation of the severity of the harm to health in the case of development of psychic health problems associated with HIV infection].

    Science.gov (United States)

    Kadochnikov, D; Poljanskij, K; Kalinin, D; Minaeva, Asp

    2015-01-01

    The objective of the present study was to develop the classifying criteria for the evaluation of the severity of the harm inflicted to human health that resulted in the development of mental disorders in response to subsequent HIV infection. The analysis of the available information about a rise in the prevalence of HIV infection and the high frequency of associated psychic disorders among the infected subjects gave evidence of the importance of this problem and the necessity to improve the existing statutory and legislative basis underlying the regulation of activities in this field. The scientifically substantiated criteria for the expert assessment of the severity of the harm to human health are proposed taking into consideration the clinical manifestations of psychic disorders.

  2. Probing silicon quantum dots by single-dot techniques

    Science.gov (United States)

    Sychugov, Ilya; Valenta, Jan; Linnros, Jan

    2017-02-01

    Silicon nanocrystals represent an important class of non-toxic, heavy-metal free quantum dots, where the high natural abundance of silicon is an additional advantage. Successful development in mass-fabrication, starting from porous silicon to recent advances in chemical and plasma synthesis, opens up new possibilities for applications in optoelectronics, bio-imaging, photovoltaics, and sensitizing areas. In this review basic physical properties of silicon nanocrystals revealed by photoluminescence spectroscopy, lifetime, intensity trace and electrical measurements on individual nanoparticles are summarized. The fabrication methods developed for accessing single Si nanocrystals are also reviewed. It is concluded that silicon nanocrystals share many of the properties of direct bandgap nanocrystals exhibiting sharp emission lines at low temperatures, on/off blinking, spectral diffusion etc. An analysis of reported results is provided in comparison with theory and with direct bandgap material quantum dots. In addition, the role of passivation and inherent interface/matrix defects is discussed.

  3. Low temperature method for synthesis of ZnS quantum dots and its luminescence characterization studies

    Energy Technology Data Exchange (ETDEWEB)

    Senthilkumar, K., E-mail: senovi2007@gmail.com [Department of Physics, AMET University, Chennai 603112 (India); Department of Physics, SRM University, Chennai 603203 (India); Kalaivani, T. [Department of Physics, SRM University, Chennai 603203 (India); Kanagesan, S. [Materials Synthesis and Characterization Laboratory (MSCL), Institute of Advanced Technology, Universiti Putra Malaysia, Serdang 43400, Selangor (Malaysia); Balasubramanian, V. [Department of Chemistry, AMET University, Chennai 603112 (India)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer We prepared zinc sulfide (ZnS) quantum dots of sizes 2.68-4.8 nm. Black-Right-Pointing-Pointer It is embedded on polyvinyl alcohol (PVA) matrix, have been synthesized at 70 Degree-Sign C by wet chemical method. Black-Right-Pointing-Pointer Optical absorption spectra showed strong blue shift, which is an indication of strong quantum confinement. Black-Right-Pointing-Pointer ZnS quantum dots exhibit strong quantum confinement effect as the optical band gap increases significantly, from 3.96 eV to 4.06 eV, compared to bulk value 3.68 eV. - Abstract: Zinc Sulfide (ZnS) quantum dots of sizes 2.68-4.8 nm, embedded on polyvinyl alcohol (PVA) matrix, have been synthesized at 70 Degree-Sign C by wet chemical method. X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), UV-vis spectroscopy and photoluminescence (PL) Spectroscopy has been adopted for sample characterization. Optical absorption spectra showed strong blue shift, which is an indication of strong quantum confinement. Photoluminescence spectra of the sample have been recorded at room temperature and observed two peaks centred around 415 nm and 440 nm. We have assigned the first peak due to band gap transitions while the later due to sulfur vacancy in the sample.

  4. Fluorescence from Individual PbS Quantum Dots

    Science.gov (United States)

    Peterson, Jeffrey

    2005-03-01

    Due to their extremely large electron, hole, and exciton Bohr radii, PbS quantum dots (QDs) can achieve levels of quantum confinement not accessible to III-V and II-VI QDs. Thus, the strong confinement regime is attained for relatively large particles, which may mitigate deleterious surface effects and impart novel properties. PbS QDs are also optically active in the near-infrared region, making these materials potentially useful for telecommunications and biotechnological applications. We will present investigations of single PbS QD fluorescence using far-field microscopy. PbS QDs were synthesized with a size-tunable exciton absorbance ranging between 765 nm and 1800 nm. Of particular note is the ability to synthesize highly luminescent, small radii QDs, allowing for fluorescence detection with high sensitivity silicon CCDs. Upon spincoating QDs onto glass substrates at densities near the single dot level, we observe fluorescence intermittency, or “blinking” and a narrowing of the fluorescence spectra relative to the ensemble, both hallmarks of single fluorophores. The fluorescence energy irreversibly blue shifts with longer integration times and higher excitation intensities, indicative of a photo-induced degradation. Photobleaching of the majority of PbS QDs occurred in 30 sec. An analysis of the blinking statistics will be discussed.

  5. [Primary Prevention during Interaction of Teachers and Students--An Interdisciplinary Modular Programme According to Psychic and Psychosomatic Disorders in the Setting of Vocational Schools].

    Science.gov (United States)

    Haufe, E; Winkelmann, C; Hacker, W; Scheuch, K

    2015-09-01

    The aim of the project was the development of a modular primary preventive programme according to psychic and psychosomatic disorders in the setting of vocational schools and the evaluation of the corresponding interventions. Preventive strategies were integrated in the basic and further education of teachers and a concept for their occupational medical care. These strategies with long-term effects were supplemented by interventions to promote health and competence directly in the field. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Improvement of psychic and somatic symptoms in adult patients with generalized anxiety disorder: examination from a duloxetine, venlafaxine extended-release and placebo-controlled trial.

    Science.gov (United States)

    Nicolini, H; Bakish, D; Duenas, H; Spann, M; Erickson, J; Hallberg, C; Ball, S; Sagman, D; Russell, J M

    2009-02-01

    This study examined the efficacy and tolerability of duloxetine and venlafaxine extended-release (XR) treatment for generalized anxiety disorder (GAD), with a secondary focus on psychic and somatic symptoms within GAD. The design was a 10-week, multi-center, double-blind placebo-controlled study of duloxetine (20 mg or 60-120 mg once daily) and venlafaxine XR (75-225 mg once daily) treatment. Efficacy was measured using the Hamilton Anxiety Rating Scale (HAMA), which includes psychic and somatic factor scores. Tolerability was measured by occurrence of treatment-emergent adverse events (TEAEs) and discontinuation rates. Adult out-patients (mean age 42.8 years; 57.1% women) with DSM-IV-defined GAD were randomly assigned to placebo (n=170), duloxetine 20 mg (n=84), duloxetine 60-120 mg (n=158) or venlafaxine XR 75-225 mg (n=169) treatment. Each of the three active treatment groups had significantly greater improvements on HAMA total score from baseline to endpoint compared with placebo (p=0.01-0.001). For the HAMA psychic factor score, both duloxetine treatment arms and venlafaxine XR demonstrated significantly greater improvement compared with placebo (p=0.01-0.001). For the HAMA somatic factor score, the mean improvement in the duloxetine 60-120 mg and venlafaxine XR groups was significantly greater than placebo (p0.05 and p0.01 respectively), whose mean improvement did not differ from the duloxetine 20 mg group (p=0.07). Groups did not differ in study discontinuation rate due to adverse events. Duloxetine and venlafaxine treatment were each efficacious for improvement of core psychic anxiety symptoms and associated somatic symptoms for adults with GAD.

  7. How much stress is needed to increase vulnerability to psychosis? A community assessment of psychic experiences (CAPE) evaluation 10 months after an earthquake in L'Aquila (Italy).

    Science.gov (United States)

    Rossi, Alessandro; di Tommaso, Silvia; Stratta, Paolo; Riccardi, Ilaria; Daneluzzo, Enrico

    2012-04-01

    Since severe stress can induce mental disorder symptoms that interact with vulnerability factors, the Community Assessment of Psychic Experiences (CAPE) was evaluated in a population of 419 young adults who survived an earthquake; results were compared to a database of 1,057 'non-exposed' subjects. Unexpectedly, earthquake survivors showed lower CAPE scores for 'small' to 'medium' effect size. Post-trauma positive changes or re-appraisal for successful adaptation may explain these findings.

  8. THE SUBJECTIVAL CONTENT OF IMAGES “SUCCESSFUL MAN” AND “SUCCESSFUL WOMAN” AS A FACTOR OF PSYCHIC ADJUSTMENT OF WOMEN IN INVOLUNTARY UNEMPLOYMENT SITUATION

    OpenAIRE

    Lopukhova Olga Gennadevna; Beglova Elmira Ildusovna

    2013-01-01

    Purpose of the study is investigation of correlation between a content of gender appearance of image “successful person” and parameters of psychic and social adjustment of women belonging to different generations.Methodology.  Subjective image “successful person” means a stable and possibly gender differentiated element of “Ideal Me” images system. It includes cognitive component (conscious and verbalization representations of typical description of successful person), and affective component...

  9. Nobel Prize for blue LEDs

    Science.gov (United States)

    Kraftmakher, Yaakov

    2015-05-01

    A brief review of lighting technologies is presented. Unavoidable restrictions for incandescent light bulbs caused by the Planck distribution and properties of the human eye are illustrated. The efficiency and luminous efficacy of thermal radiation are calculated for various temperatures; the results clearly show the limitations for thermal radiators. The only way to overcome these limitations is using non-thermal radiators, such as fluorescent lamps and light-emitting diodes (LEDs). Unique advantages of LEDs undoubtedly made a revolution in this field. A crucial element of this progress is the blue LEDs (Nobel Prize 2014). Some experiments with a blue and a green LED are described: (i) the luminescence triggered in a green-yellow phosphor inside a white LED by the blue LED; (ii) radiant spectra and ‘efficiency droop’ in the LEDs; (iii) modulation of the blue LED up to 4 MHz; and (iv) the h/e ratio from the turn-on voltage of the green LED. The experiments are suitable for undergraduate laboratories and usable as classroom demonstrations.

  10. Blue Ocean vs. Five Forces

    NARCIS (Netherlands)

    A.E. Burke (Andrew); A.J. van Stel (André); A.R. Thurik (Roy)

    2010-01-01

    textabstractThe article reports on the authors' research in the Netherlands which focused on a profit model in Dutch retail stores and a so-called blue-ocean approach which requires a new market that attracts consumers and increases profits. Topics include the competitive strategy approach to

  11. The blue revolution in asia

    DEFF Research Database (Denmark)

    Jespersen, Karen Sau; Ponte, Stefano; Kelling, Ingrid

    2014-01-01

    In this article, we examine the upgrading trajectories of selected aquaculture value chains in four Asian countries and the links between upgrading and three factors of value chain governance: coordination mechanisms; types of drivers; and domestic regulation. We find instances of improving produ...... of upgrading the "blue revolution" in Asia...

  12. The deceased child in the psychic and social worlds of bereaved parents during the resolution of grief.

    Science.gov (United States)

    Klass, D

    1997-01-01

    A core dynamic by which grief is resolved by parents in Bereaved Parents, a self-help group, is a series of transformations of the inner representation of the dead child in the parent's inner world and in the parent's social world. As the reality of the child's death as well as the reality of the parent's continuing bond with the child are made part of the socially shared reality, the inner representation of the child can be transformed in the parent's psychic life. The end of grief is not severing the bond with the dead child, but integrating the child into the parent's life in a different way than when the child was alive. This article traces the course of the inner representation of the child in the parent's inner life and social world as the parent progresses through Bereaved Parents. It concludes with some comments on the differences that should be maintained between scholarly and popular understandings of phenomena in the continuing bonds survivors maintain with the dead.

  13. Validation of the Community Assessment Psychic Experiences -42 (CAPE-42) in Spanish college students and patients with psychosis.

    Science.gov (United States)

    Fonseca-Pedrero, Eduardo; Paino, Mercedes; Lemos-Giráldez, Serafín; Muñiz, José

    2012-01-01

    Psychotic-like experiences can be considered as a vulnerability marker for psychotic disorders. The psychometric assessment of the extended psychosis phenotype has advanced considerably in recent years, although it must continue to deepen the quality of self-reports available for its assessment in Spanish population. The main goal was to analyze the psychometric quality of the Community Assessment Psychic Experiences-42 (CAPE-42) in Spanish college students and patients with psychosis. The final sample was comprised of a total of 660 students (M = 20.3 years, SD = 2.6) and 97 patients with psychosis (M = 35.4 years, SD = 10.2). The goodness of fit indices resulting from the confirmatory factor analysis that tested the hypothesized three-dimensional model (Positive, Negative and Depressive) were not adequate. In contrast, the exploratory factor analysis yielded a three-dimensional solution. Internal consistency values for the three dimensions of the CAPE-42 ranged between 0.78 and 0.89 in the sample of students and between 0.84 and 0.93 in the patients with psychosis. The CAPE-42 scores correlated statistically significant with delusions and trait anxiety and state. These results show further evidence of validity of the CAPE-42 scores in samples of the Spanish population and support its use as a tool for the assessment of the extended psychosis phenotype.

  14. [Actual care and funding situation with regard to mother-child units for psychic disorders associated with pregnancy in Germany].

    Science.gov (United States)

    Jordan, Wolfgang; Bielau, Hendrik; Cohrs, Stefan; Hauth, Iris; Hornstein, Christiane; Marx, Alexandra; Reck, Corinna; von Einsiedel, Regina

    2012-07-01

    CONCERN: The current care and financial situation of mother-child units for psychic disorders associated with pregnancies in Germany should be documented in preparation for the development of the new reimbursement system for psychiatry and psychosomatics. In accordance with the last survey of 2005, a brief questionnaire was developed and a nationwide poll was conducted. The survey revealed severe (10 fold) service deficits for severely and gravely mentally ill mothers, who require an inpatient treatment with specific professional competence. Compared with the last poll, these service deficits have increased. This is due to continued insufficient funding and unresolved financing in the new reimbursement system. With the establishment of an additional code for mother-child treatment the precondition for ensuring the funding of this important care form in the new reimbursement system was created. It is to be hoped that the decision-makers of health policy will finally face up to their social responsibility and ensure adequate funding of the additional diagnostic and therapeutic expenditure of mother-child treatment. The health care providers have an obligation to implement a transparent record of services of the additional expenditure and to augment the national evaluation approaches to inpatient mother-child treatments. © Georg Thieme Verlag KG Stuttgart · New York.

  15. The formation of social reintegration strategies of the psychic suffering carrier: new directions for psychiatric nursing in Brazil.

    Science.gov (United States)

    Souza, Emilia Jales Simões de; Moreira, Lilian Hortale de Oliveira; Cardoso, Maria Manuela Vila Nova; Ferreira, Rosa Gomes dos Santos; Silva, Thuany Cristine Santos da

    2014-09-01

    This is an exploratory and descriptive study of a qualitative nature. Its objective is to analyse the formation of strategies for social reintegration of the psychic suffering carrier in the practice of nurses working in hospital psychiatric institutions. For this study, we use, as a basis, the concepts and processes of the formation of strategies presented by Isabel Nicholau, 2001. Twelve nurses with health care experience in hospital psychiatric institutions participated in this study, and data collection occurred through semi-structured interviews in the year 2013. The data revealed that, in addition to human, material, and financial resources, institutional support is needed as is articulation and interaction among professionals and services. The importance of the social dimension and of the negotiation process depicts the development of conception of collective and integrated work. We conclude that strategies are emerging from the daily life of work and are not limited to a rational logic of cost and fundraising, but instead are developed through a negotiated process.

  16. Dot-in-Well Quantum-Dot Infrared Photodetectors

    Science.gov (United States)

    Gunapala, Sarath; Bandara, Sumith; Ting, David; Hill, cory; Liu, John; Mumolo, Jason; Chang, Yia Chung

    2008-01-01

    Dot-in-well (DWELL) quantum-dot infrared photodetectors (QDIPs) [DWELL-QDIPs] are subjects of research as potentially superior alternatives to prior QDIPs. Heretofore, there has not existed a reliable method for fabricating quantum dots (QDs) having precise, repeatable dimensions. This lack has constituted an obstacle to the development of uniform, high-performance, wavelength-tailorable QDIPs and of focal-plane arrays (FPAs) of such QDIPs. However, techniques for fabricating quantum-well infrared photodetectors (QWIPs) having multiple-quantum- well (MQW) structures are now well established. In the present research on DWELL-QDIPs, the arts of fabrication of QDs and QWIPs are combined with a view toward overcoming the deficiencies of prior QDIPs. The longer-term goal is to develop focal-plane arrays of radiationhard, highly uniform arrays of QDIPs that would exhibit high performance at wavelengths from 8 to 15 m when operated at temperatures between 150 and 200 K. Increasing quantum efficiency is the key to the development of competitive QDIP-based FPAs. Quantum efficiency can be increased by increasing the density of QDs and by enhancing infrared absorption in QD-containing material. QDIPs demonstrated thus far have consisted, variously, of InAs islands on GaAs or InAs islands in InGaAs/GaAs wells. These QDIPs have exhibited low quantum efficiencies because the numbers of QD layers (and, hence, the areal densities of QDs) have been small typically five layers in each QDIP. The number of QD layers in such a device must be thus limited to prevent the aggregation of strain in the InAs/InGaAs/GaAs non-lattice- matched material system. The approach being followed in the DWELL-QDIP research is to embed In- GaAs QDs in GaAs/AlGaAs multi-quantum- well (MQW) structures (see figure). This material system can accommodate a large number of QD layers without excessive lattice-mismatch strain and the associated degradation of photodetection properties. Hence, this material

  17. Quantum Dot Light Emitting Diode

    Energy Technology Data Exchange (ETDEWEB)

    Keith Kahen

    2008-07-31

    The project objective is to create low cost coatable inorganic light emitting diodes, composed of quantum dot emitters and inorganic nanoparticles, which have the potential for efficiencies equivalent to that of LEDs and OLEDs and lifetime, brightness, and environmental stability between that of LEDs and OLEDs. At the end of the project the Recipient shall gain an understanding of the device physics and properties of Quantum-Dot LEDs (QD-LEDs), have reliable and accurate nanocrystal synthesis routines, and have formed green-yellow emitting QD-LEDs with a device efficiency greater than 3 lumens/W, a brightness greater than 400 cd/m2, and a device operational lifetime of more than 1000 hours. Thus the aim of the project is to break the current cost-efficiency paradigm by creating novel low cost inorganic LEDs composed of inorganic nanoparticles.

  18. Quantum Dot Light Emitting Diode

    Energy Technology Data Exchange (ETDEWEB)

    Kahen, Keith

    2008-07-31

    The project objective is to create low cost coatable inorganic light emitting diodes, composed of quantum dot emitters and inorganic nanoparticles, which have the potential for efficiencies equivalent to that of LEDs and OLEDs and lifetime, brightness, and environmental stability between that of LEDs and OLEDs. At the end of the project the Recipient shall gain an understanding of the device physics and properties of Quantum-Dot LEDs (QD-LEDs), have reliable and accurate nanocrystal synthesis routines, and have formed green-yellow emitting QD-LEDs with a device efficiency greater than 3 lumens/W, a brightness greater than 400 cd/m{sup 2}, and a device operational lifetime of more than 1000 hours. Thus the aim of the project is to break the current cost-efficiency paradigm by creating novel low cost inorganic LEDs composed of inorganic nanoparticles.

  19. Protective effects of soft acrylic yellow filter against blue light-induced retinal damage in rats.

    Science.gov (United States)

    Tanito, Masaki; Kaidzu, Sachiko; Anderson, Robert E

    2006-12-01

    Recently, a yellow intraocular lens (IOL) was developed for the purpose of reducing potential blue light-induced retinal damage after cataract surgery. However, the effect of yellow filters on retinal protection remains to be clarified. To test the protective effects of yellow filters on blue light-induced retinal damage, a yellow and a clear soft acrylic filter were attached to the right and left eyes, respectively, of albino rats and exposed to 4.5 k lux blue fluorescent lights with peak wavelength at 420 nm (ranging 380-500 nm; short blue) or 446 nm (ranging 400-540 nm; long blue) for 6h. To assess retinal damage, the electroretinogram (ERG) was recorded at 7 days, outer nuclear layer (ONL) thickness and area were measured at 7 days, apoptosis was analyzed by TUNEL staining at 24 h, and the level of lipid peroxidation in retinas was assessed by Western dot blots using specific antibodies against 4-hydroxynonenal (4-HNE)- and carboxyethylpyrrole (CEP)-modified proteins immediately after light exposure. After short blue light exposure, a- and b-wave ERG amplitudes and the ONL thickness at 1-2.5 mm inferior and 0.5-2.5 mm superior to optic nerve head (ONH) were significantly reduced. TUNEL staining in the ONL at 0-2 mm inferior and 1-2 mm superior to the ONH, and retinal levels of 4-HNE- and CEP-modified proteins were significantly increased in the clear filter-covered eyes compared to yellow filter-covered eyes. After long blue light exposure, the only difference seen was a greater ONL thickness at 1.5 mm superior to the ONH in yellow filter-covered eye. Transmission of light through the yellow filter was 58% for short blue and 89% for long blue compared to the clear filter. The ONL area was not different between clear filter-covered and -uncovered eyes after exposure to short or long blue light. Given the results, yellow IOL material protects the retina against acute shorter wavelength blue light exposure more effectively than the clear IOL material.

  20. Quantum dots: lasers and amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Bimberg, Dieter; Ledentsov, Nikolai [Institut fuer Festkoerperphysik, PN5-2, Technische Universitaet Berlin, Hardenbergstrasse 36, 10623 (Germany)

    2003-06-25

    Continuous wave room-temperature output power of {approx} 3 W for edge emitters and of 1.2 mW for vertical-cavity surface-emitting lasers is realized for GaAs-based devices using InAs quantum dots (QDs) operating at 1.3 {mu}m. Characteristic temperatures up to 170 K below 330 K are realized. Simultaneously, differential efficiency exceeds 80% for these devices. Lasers emitting up to 12 W at 1140-1160 nm are useful as pump sources for Tm{sup 3+}-doped fibres for frequency up-conversion to 470 nm. Both types of lasers show transparency current densities of 6 A cm{sup -2} per dot layer, {eta}{sub int} = 98% and {alpha}{sub i} around 1.5 cm{sup -1}. Long operation lifetimes (above 3000 h at 50 deg C heatsink temperature at 1.5 W CW) and improved radiation hardness as compared to quantum well (QW) devices are manifested. Cut-off frequencies of about 10 GHz at 1100 nm and 6 GHz at 1300 nm and low {alpha} factors resulting in reduced filamentation and improved M{sup 2} values in single-mode operation are realized. Quantum dot semiconductor optical amplifiers (QD SOAs) demonstrate gain recovery times of 120-140 fs, 4-7 times faster than bulk/QW SOAs. The breakthrough became possible due to the development of self-organized growth in QD technology. (topical review)

  1. Influence of the Shell Thickness and Ratio Between Core Elements on Photostability of the CdTe/CdS Core/Shell Quantum Dots Embedded in a Polymer Matrix.

    Science.gov (United States)

    Doskaliuk, Nataliia; Khalavka, Yuriy; Fochuk, Petro

    2016-12-01

    This paper reports a study of photooxidation and photomodification processes of the CdTe/CdS quantum dots embedded in a polymer matrix under ambient condition. During the first few minutes of irradiation, the quasi-inverse increase in photoluminescence intensity has been observed indicating the passivation of the nanocrystal surface traps by water molecules. A prolonged irradiation of the polymer film containing CdTe/CdS quantum dots leads to a significant decrease in the photoluminescence intensity together with the "blue shift" of the photoluminescence peak energy associated with quantum dot photooxidation. The mechanisms of the CdTe/CdS core/shell quantum dot photooxidation and photomodification in a polymer matrix are discussed. We have found a correlation between the photostability of the quantum dots and the CdS shell thickness as well as the ratio of core elements.

  2. Code Blue evaluation in children's hospital.

    Science.gov (United States)

    Sahin, Kubra Evren; Ozdinc, Oktay Zeki; Yoldas, Suna; Goktay, Aylin; Dorak, Selda

    2016-01-01

    True alarm rate of the Code Blue cases is at a low level in the Dr. Behçet Uz Children's Hospital in İzmir. This study aims to analyse the use of the Code Blue alarm cases in the children's hospital. This retrospective clinical study evaluated the age and the gender of the cases, the arriving time of the Code Blue team, the date and time of the Code Blue Call, the reasons of the Code Blue Call, and the verification which were all obtained from the Code Blue forms of the hospital dated between January 2014 and January 2015. The data of 139 Code Blue cases' forms were investigated and was divided into two groups: before and after the education containing 88 and 51 cases, respectively. Conversive disorder (26% to 13%, Pode Blue cases were false calls with female greater than male (Pode that is to say pre-diagnosis team should be formed.

  3. Barrier Engineered Quantum Dot Infrared Photodetectors

    Science.gov (United States)

    2015-06-01

    AFRL-RV-PS- AFRL-RV-PS- TR-2015-0111 TR-2015-0111 BARRIER ENGINEERED QUANTUM DOT INFRARED PHOTODETECTORS Sanjay Krishna Center for High Technology...2011 – 22 May 2012 4. TITLE AND SUBTITLE Barrier Engineered Quantum Dot Infrared Photodetectors 5a. CONTRACT NUMBER FA9453-12-1-0336 5b. GRANT...is Unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT To investigate barrier engineered designs to reduce the dark current in quantum dot infrared

  4. Quantum interference induced photon blockade in a coupled single quantum dot-cavity system.

    Science.gov (United States)

    Tang, Jing; Geng, Weidong; Xu, Xiulai

    2015-03-18

    We propose an experimental scheme to implement a strong photon blockade with a single quantum dot coupled to a nanocavity. The photon blockade effect can be tremendously enhanced by driving the cavity and the quantum dot simultaneously with two classical laser fields. This enhancement of photon blockade is ascribed to the quantum interference effect to avoid two-photon excitation of the cavity field. Comparing with Jaynes-Cummings model, the second-order correlation function at zero time delay g((2))(0) in our scheme can be reduced by two orders of magnitude and the system sustains a large intracavity photon number. A red (blue) cavity-light detuning asymmetry for photon quantum statistics with bunching or antibunching characteristics is also observed. The photon blockade effect has a controllable flexibility by tuning the relative phase between the two pumping laser fields and the Rabi coupling strength between the quantum dot and the pumping field. Moreover, the photon blockade scheme based on quantum interference mechanism does not require a strong coupling strength between the cavity and the quantum dot, even with the pure dephasing of the system. This simple proposal provides an effective way for potential applications in solid state quantum computation and quantum information processing.

  5. Photoluminescence Properties Research on Graphene Quantum Dots/Silver Composites.

    Science.gov (United States)

    Wang, Jun; Li, Yan; Zhang, Bo-Ping; Xie, Dan-Dan; Ge, Juan; Liu, Hui

    2016-04-01

    Graphene quantum dots (GQDs) possess unique properties of graphene and exhibit a series of new phenomena of 0 dimension (D) carbon materials. Thus, GQDs have attracted much attention from researchers and have shown great promise for many applications. Recently, many works focus on GQDs-metal ions and metal nanoparticles (NPs). Although, many researches point out that metal ions and metal NPs have significant effect on photoluminescence (PL) feature of GQDs, mainly focus on PL intensity. Here, for the first time, we reported that metal NPs also affected PL peak position which was dependent on the mix mechanism of metal and GQDs. When GQDs-silver (Ag) composite mixed by physical method and excited at a wavelength of 320 nm, PL peak position of composites first showed blue-shifted then red-shifted with increasing of Ag content. However, if GQDs-Ag composite prepared by chemical method, PL peak position of the composites blue-shifted. Furthermore, the shift of PL peak position of GQDs-Ag prepared both for physical and chemical method displayed excitation-dependent feature. When the excitation wavelength approached to Ag SPR peaks, no obvious PL shift was observed. The mechanism for different PL shifts and the phenomenon of excitation-dependent PL shift as well as the formation mechanism of GQDs-Ag composite by chemical method are discussed in detail in this paper.

  6. Today's DOT and the quest for more accountable organizational structures.

    Science.gov (United States)

    2005-12-01

    This study investigates the impact of DOT organizational structures on effective transportation planning and performance. A review of the 50 state DOT authorizing statutes and DOT organizational charts found minimal differences in organizational stru...

  7. Spin Switching via Quantum Dot Spin Valves

    Science.gov (United States)

    Gergs, N. M.; Bender, S. A.; Duine, R. A.; Schuricht, D.

    2018-01-01

    We develop a theory for spin transport and magnetization dynamics in a quantum dot spin valve, i.e., two magnetic reservoirs coupled to a quantum dot. Our theory is able to take into account effects of strong correlations. We demonstrate that, as a result of these strong correlations, the dot gate voltage enables control over the current-induced torques on the magnets and, in particular, enables voltage-controlled magnetic switching. The electrical resistance of the structure can be used to read out the magnetic state. Our model may be realized by a number of experimental systems, including magnetic scanning-tunneling microscope tips and artificial quantum dot systems.

  8. Quantum dots for quantum information technologies

    CERN Document Server

    2017-01-01

    This book highlights the most recent developments in quantum dot spin physics and the generation of deterministic superior non-classical light states with quantum dots. In particular, it addresses single quantum dot spin manipulation, spin-photon entanglement and the generation of single-photon and entangled photon pair states with nearly ideal properties. The role of semiconductor microcavities, nanophotonic interfaces as well as quantum photonic integrated circuits is emphasized. The latest theoretical and experimental studies of phonon-dressed light matter interaction, single-dot lasing and resonance fluorescence in QD cavity systems are also provided. The book is written by the leading experts in the field.

  9. Preparation of tin oxide quantum dots

    Science.gov (United States)

    Fauzi, N. F. S. M.; Kamarulzaman, N.; Kasim, M. F.; Chayed, N. F.; Aziz, N. D. A.

    2017-09-01

    Quantum dots are interesting nanostructures with have novel physical and chemical characteristics. It is not an easy task to obtain quantum dots because materials tend to agglomerate. In this work, SnO2 quantum dots have been successfully synthesized via a simple and low cost method which is the sol-gel method. Thermal analysis of the precursors were carried out using a Simultaneous Thermogravimetric Analyzer (STA). The annealed samples were characterized using X-Ray Diffraction (XRD) for phase studies. Finally, the crystallite size and morphology of tin oxide quantum dots were determined using Field Emission Scanning Electron Microscopy (FESEM).

  10. POLARON IN CYLINDRICAL AND SPHERICAL QUANTUM DOTS

    Directory of Open Access Journals (Sweden)

    L.C.Fai

    2004-01-01

    Full Text Available Polaron states in cylindrical and spherical quantum dots with parabolic confinement potentials are investigated applying the Feynman variational principle. It is observed that for both kinds of quantum dots the polaron energy and mass increase with the increase of Frohlich electron-phonon coupling constant and confinement frequency. In the case of a spherical quantum dot, the polaron energy for the strong coupling is found to be greater than that of a cylindrical quantum dot. The energy and mass are found to be monotonically increasing functions of the coupling constant and the confinement frequency.

  11. Transmission and scarring in graphene quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Huang Liang; Lai Yingcheng; Ferry, David K; Akis, Richard; Goodnick, Stephen M [Department of Electrical Engineering, Arizona State University, Tempe, AZ 85287 (United States)

    2009-08-26

    We study electronic transport in quantum-dot structures made of graphene. Focusing on the rectangular dot geometry and utilizing the non-equilibrium Green's function to calculate the transmission in the tight-binding framework, we find significant fluctuations in the transmission as a function of the electron energy. The fluctuations are correlated with the formation of quantum scarring states, or pointer states in the dot. Both enhancement and suppression of transmission have been observed. As the size of the quantum dot is increased, more scarring states can be formed, leading to stronger transmission or conductance fluctuations.

  12. Mixed-quantum-dot solar cells.

    Science.gov (United States)

    Yang, Zhenyu; Fan, James Z; Proppe, Andrew H; Arquer, F Pelayo García de; Rossouw, David; Voznyy, Oleksandr; Lan, Xinzheng; Liu, Min; Walters, Grant; Quintero-Bermudez, Rafael; Sun, Bin; Hoogland, Sjoerd; Botton, Gianluigi A; Kelley, Shana O; Sargent, Edward H

    2017-11-06

    Colloidal quantum dots are emerging solution-processed materials for large-scale and low-cost photovoltaics. The recent advent of quantum dot inks has overcome the prior need for solid-state exchanges that previously added cost, complexity, and morphological disruption to the quantum dot solid. Unfortunately, these inks remain limited by the photocarrier diffusion length. Here we devise a strategy based on n- and p-type ligands that judiciously shifts the quantum dot band alignment. It leads to ink-based materials that retain the independent surface functionalization of quantum dots, and it creates distinguishable donor and acceptor domains for bulk heterojunctions. Interdot carrier transfer and exciton dissociation studies confirm efficient charge separation at the nanoscale interfaces between the two classes of quantum dots. We fabricate the first mixed-quantum-dot solar cells and achieve a power conversion of 10.4%, which surpasses the performance of previously reported bulk heterojunction quantum dot devices fully two-fold, indicating the potential of the mixed-quantum-dot approach.

  13. 21 CFR 133.106 - Blue cheese.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Blue cheese. 133.106 Section 133.106 Food and... CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.106 Blue cheese. (a) Description. (1) Blue cheese is the food prepared by the procedure set...

  14. Novel cookie-with-chocolate carbon dots displaying extremely acidophilic high luminescence.

    Science.gov (United States)

    Lu, Siyu; Zhao, Xiaohuan; Zhu, Shoujun; Song, Yubin; Yang, Bai

    2014-11-21

    A fluorescent carbon dot with a cookie-with-chocolate film structure (about 5 × 5 μm(2)) showed a high fluorescence quantum yield (61.12%) at low pH. It was hydrothermally synthesized from l-serine and l-tryptophan. The formation mechanism of the film with carbon dots (CDs) was investigated. The film structure was formed by hydrogen bonding and π-π stacking interactions between aromatic rings. The strong blue fluorescence of the CDs increased under strong acidic conditions owing to the changes in the N-groups. These cookie-like CDs are attractive for their potential use as effective fluorescent probes for the sensitive detection of aqueous H(+) and Fe(3+).

  15. Intersubband Optical Absorption Coefficients and Refractive Index Changes in a Gaussian Spherical Quantum Dot

    Science.gov (United States)

    Ehsanfard, Najmeh; Kazerani Vahdani, Mohammad Reza

    2015-07-01

    The effects of smooth confining potential on the linear and nonlinear optical properties are investigated with Gaussian confining potential in Quantum Dots (GQDs). To this end the effective mass approximation, the compact density matrix approach, and iterative method are used to calculate linear and nonlinear Absorption Coefficient (AC) and Refractive Index (RI) change of an electron confined in GQD. The effects of confining potential and radius of GQD and also incident optical intensity have been investigated. The results show that increasing confining potential decreases the refractive index magnitude and shifts the peak values to the higher energy regions. It is also shown that the peak values of absorption coefficient increase by increasing confining potential. Both absorption coefficient and refractive index experience red shift by increasing the size of quantum dot. It is also shown that transition from step potential to Gaussian potential makes AC and RI to experience a blue shift.

  16. Quantum Dot Spectrum Converters for Enhanced High Efficiency Photovoltaics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This research proposes to enhance solar cell efficiency, radiation resistance and affordability. The Quantum Dot Spectrum Converter (QDSC) disperses quantum dots...

  17. Status of Blue Ridge Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

  18. Thermoluminescence (TL) of Egyptian Blue

    Energy Technology Data Exchange (ETDEWEB)

    Schvoerer, M.; Delavergne, M.-C.; Chapoulie, R.

    1988-01-01

    Egyptian Blue is a synthesized crystalline pictorial pigment with formula CaCuSi/sub 4/O/sub 10/. It has been used in Egypt and Mesopotamia from the 3rd millenium B.C. A preliminary experiment on a recently synthesized sample showed that this pigment is thermoluminescent after ..beta.. irradiation (/sup 90/Sr). As the signal intensity grows linearly with the administered dose within the temperature range commonly used in TL dating, we have been looking for this phenomenon from archaeological pigments. It was encountered with two samples found in excavation. From its intensity and stability we concluded that Egyptian Blue can be dated using TL. This first and positive result encouraged us to extend the method to other types of mineral pigments synthesized by early man, and to suggest that it may be used for direct dating of ancient murals.

  19. The Physics of the Blues

    Science.gov (United States)

    Gibson, J. Murray

    2009-03-01

    In looking at the commonalities between music and science, one sees that the musician's palette is based on the principles of physics. The pitch of a musical note is determined by the frequency of the sound wave. The scales that musicians use to create and play music can be viewed as a set of rules. What makes music interesting is how musicians develop those rules and create ambiguity with them. I will discuss the evolution of western musical scales in this context. As a particular example, ``Blue'' notes are very harmonic notes that are missing from the equal temperament scale. The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting. Live keyboard demonstrations will be used. Beyond any redeeming entertainment value the talk will emphasize the serious connections between science and art in music. Nevertheless tips will be accepted.

  20. Novel cookie-with-chocolate carbon dots displaying extremely acidophilic high luminescence

    Science.gov (United States)

    Lu, Siyu; Zhao, Xiaohuan; Zhu, Shoujun; Song, Yubin; Yang, Bai

    2014-10-01

    A fluorescent carbon dot with a cookie-with-chocolate film structure (about 5 × 5 μm2) showed a high fluorescence quantum yield (61.12%) at low pH. It was hydrothermally synthesized from l-serine and l-tryptophan. The formation mechanism of the film with carbon dots (CDs) was investigated. The film structure was formed by hydrogen bonding and π-π stacking interactions between aromatic rings. The strong blue fluorescence of the CDs increased under strong acidic conditions owing to the changes in the N-groups. These cookie-like CDs are attractive for their potential use as effective fluorescent probes for the sensitive detection of aqueous H+ and Fe3+.A fluorescent carbon dot with a cookie-with-chocolate film structure (about 5 × 5 μm2) showed a high fluorescence quantum yield (61.12%) at low pH. It was hydrothermally synthesized from l-serine and l-tryptophan. The formation mechanism of the film with carbon dots (CDs) was investigated. The film structure was formed by hydrogen bonding and π-π stacking interactions between aromatic rings. The strong blue fluorescence of the CDs increased under strong acidic conditions owing to the changes in the N-groups. These cookie-like CDs are attractive for their potential use as effective fluorescent probes for the sensitive detection of aqueous H+ and Fe3+. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr03965c

  1. Ol' Blue Eyes, in Focus

    Science.gov (United States)

    Nelson, Michael

    2009-01-01

    Scholarly books with "identity" and "culture" in the title have loomed large on academic publishing lists for several years. Scholarly books with "Sinatra" in the title are a more recent phenomenon. Despite his six-decade career as the Voice (the 1940s), the Chairman of the Board (the 50s and 60s), and Ol' Blue Eyes (the 70s through his death, in…

  2. Faktor-faktor yang Mempengaruhi Postpartum Blues

    OpenAIRE

    ', Desfanita '; ', Misrawati '; ', Arneliwati '

    2016-01-01

    Postpartum blues (baby blues)is a sad condition which is faced by certain mothers after giving birth, every mothers has a tendency for having a postpartum blues (baby blues). The purpose of this study is to explore the factors which affect the postpartum blues syndrome. The analysis method of this study used a descriptive correlation design. The study was held in the state hospital of Riau (RSUD Arifin Achmad) and Petala Bumi hospital. A purposive sampling technigue. Was used in this study to...

  3. Models of Individual Blue Stragglers

    Science.gov (United States)

    Sills, Alison

    This chapter describes the current state of models of individual blue stragglers. Stellar collisions, binary mergers (or coalescence), and partial or ongoing mass transfer have all been studied in some detail. The products of stellar collisions retain memory of their parent stars and are not fully mixed. Very high initial rotation rates must be reduced by an unknown process to allow the stars to collapse to the main sequence. The more massive collision products have shorter lifetimes than normal stars of the same mass, while products between low mass stars are long-lived and look very much like normal stars of their mass. Mass transfer can result in a merger, or can produce another binary system with a blue straggler and the remnant of the original primary. The products of binary mass transfer cover a larger portion of the colour-magnitude diagram than collision products for two reasons: there are more possible configurations which produce blue stragglers, and there are differing contributions to the blended light of the system. The effects of rotation may be substantial in both collision and merger products, and could result in significant mixing unless angular momentum is lost shortly after the formation event. Surface abundances may provide ways to distinguish between the formation mechanisms, but care must be taken to model the various mixing mechanisms properly before drawing strong conclusions. Avenues for future work are outlined.

  4. Noite e dia e alguns monocromos psíquicos Night and day - and some psychical monochromes

    Directory of Open Access Journals (Sweden)

    Edson Luiz André de Sousa

    2006-06-01

    Full Text Available O artigo apresenta uma leitura do conto de Jack London "A sombra e o brilho" mostrando o funcionamento do princípio da mímesis no processo de identificação. Propõe-se a expressão monocromos psíquicos para esses espaços mentais de indiferenciação entre o eu e o Outro. Adota-se a tese de Caillois, que afirma que o eu é permeável ao espaço. Nessa perspectiva, o tema do duplo, amplamente desenvolvido por Freud, é fundamental. Partindo-se de notas sobre o trabalho do fotógrafo cego Bavcar, procura-se mostrar alguns traços da estrutura do olhar. O artigo finaliza mostrando as conexões possíveis dessas reflexões para a prática psicanalítica.The paper presents a reading of Jack London's tale "The Shadow and the brightness", showing how the principle of mimesis works in the process of the identification. We propose to call psychical monochromes the spaces of mental indifference between the self and the other. We follow the thesis of Roger Caillois: "the self is permeable in the space". In this perspective, the subject of the double, developped by Freud is essential. We try to show the dialectic of the structure of the look based in some notes about the work of the blind photographer Bavcar. The article finish with showing the possibles connections of all these points with the clinical work.

  5. Nitrogen-Doped Carbon Dots for "green" Quantum Dot Solar Cells.

    Science.gov (United States)

    Wang, Hao; Sun, Pengfei; Cong, Shan; Wu, Jiang; Gao, Lijun; Wang, Yun; Dai, Xiao; Yi, Qinghua; Zou, Guifu

    2016-12-01

    Considering the environment protection, "green" materials are increasingly explored for photovoltaics. Here, we developed a kind of quantum dots solar cell based on nitrogen-doped carbon dots. The nitrogen-doped carbon dots were prepared by direct pyrolysis of citric acid and ammonia. The nitrogen-doped carbon dots' excitonic absorption depends on the N-doping content in the carbon dots. The N-doping can be readily modified by the mass ratio of reactants. The constructed "green" nitrogen-doped carbon dots solar cell achieves the best power conversion efficiency of 0.79 % under AM 1.5 G one full sun illumination, which is the highest efficiency for carbon dot-based solar cells.

  6. Localized Eruptive Blue Nevi after Herpes Zoster

    Directory of Open Access Journals (Sweden)

    Fany Colson

    2016-05-01

    Full Text Available A 52-year-old White man presented with a dozen small, well-restricted, punctiform, asymptomatic, blue-gray macules on the left shoulder. A few months earlier, he had been treated with oral acyclovir for herpes zoster (HZ affecting the left C7–C8 dermatomes. All the blue macules appeared over a short period of time and then remained stable. The patient had not experienced any previous trauma or had tattooing in this anatomical region. The clinical diagnosis suggested blue nevi. Dermatoscopy revealed small, well-limited, dark-blue, compact, homogeneous areas evoking dermal blue nevi. An excisional biopsy was performed and the histological examination confirmed a blue nevus. As far as we are aware of, this is the first report of eruptive blue nevi following HZ, and it should be included in the differential diagnosis of zosteriform dermatoses responding to an isotopic pathway. In addition, a brief review concerning eruptive nevi is presented.

  7. Graphene-quantum-dots-based ratiometric fluorescent probe for visual detection of copper ion.

    Science.gov (United States)

    Sun, Xiangying; Liu, Pengchao; Wu, Lulu; Liu, Bin

    2015-10-07

    A novel dual-photoluminescence probe for Cu(2+) has been developed, in which the graphene quantum dots with blue emission and CdTe QDs with yellow emission act as internal standard and probe, respectively. The photoluminescence probe exhibited selective sensing for Cu(2+) with a limit of detection (3SD/k) of 5.3 × 10(-8) M and showed its potential application in visual imaging. The results indicated that the constructed probe can be employed for sensing Cu(2+) by the naked eye, and also for monitoring intracellular Cu(2+).

  8. Color-tunable light emitting diodes based on quantum dot suspension.

    Science.gov (United States)

    Luo, Zhenyue; Chen, Haiwei; Liu, Yifan; Xu, Su; Wu, Shin-Tson

    2015-04-01

    We propose a color-tunable light emitting diode (LED) consisting of a blue LED as the light source and quantum dot (QD) suspension as the color-conversion medium. The LED color temperature can be controlled by varying the liquid volume of each QD suspension with different photoluminescence colors. We simulate and optimize the light efficiency and color quality of the color-tunable LED and also fabricated a prototype to prove concept. The proposed color-tunable LED exhibits several advantages such as excellent color-rendering property, simple structure and driving mechanism, as well as high energy efficiency. Its potential applications include circadian rhythm regulation and healthy lighting.

  9. Post-growth thermal treatment of the InAs/GaAs quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Jasinski, J.; Babinski, A.; Bozek, R.; Baranowski, J.M.

    2000-11-22

    The effect of post-growth thermal treatment of the InAs/GaAs quantum dots is investigated in this work. The photoluminescence (PL) and transmission electron microscopy (TEM) studies of samples annealed at temperatures up to 950 degrees C are presented. A complete dissolution of QDs and substantial broadening of the wetting layer (WL) can be seen from TEM. We propose that the thermally induced modification of the WL rather than QDs can be responsible for a blue-shift and narrowing of PL peaks in structures containing InAs/GaAs QDs.

  10. InGaAs/GaAs quantum dot interdiffiusion induced by cap layer overgrowth

    Energy Technology Data Exchange (ETDEWEB)

    Jasinski, J.; Babinski, A.; Czeczott, M.; Bozek, R.

    2000-06-28

    The effect of thermal treatment during and after growth of InGaAs/GaAs quantum dot (QD) structures was studied. Transmission electron microscopy and atomic force microscopy confirmed the presence of interacting QDs, as was expected from analysis of temperature dependence of QD photoluminescence (PL) peak. The results indicate that the effect of post-growth annealing can be similar to the effect of elevated temperature of capping layer growth. Both, these thermal treatments can lead to a similar In and Ga interdiffiusion resulting in a similar blue-shift of QD PL peak.

  11. Green Synthesis of Bifunctional Fluorescent Carbon Dots from Garlic for Cellular Imaging and Free Radical Scavenging.

    Science.gov (United States)

    Zhao, Shaojing; Lan, Minhuan; Zhu, Xiaoyue; Xue, Hongtao; Ng, Tsz-Wai; Meng, Xiangmin; Lee, Chun-Sing; Wang, Pengfei; Zhang, Wenjun

    2015-08-12

    Nitrogen and sulfur codoped carbon dots (CDs) were prepared from garlic by a hydrothermal method. The as-prepared CDs possess good water dispersibility, strong blue fluorescence emission with a fluorescent quantum yield of 17.5%, and excellent photo and pH stabilities. It is also demonstrated that the fluorescence of CDs are resistant to the interference of metal ions, biomolecules, and high ionic strength environments. Combining with low cytotoxicity properties, CDs could be used as an excellent fluorescent probe for cellular multicolor imaging. Moreover, the CDs were also demonstrated to exhibit favorable radical scavenging activity.

  12. Covalent Crosslinking of Graphene Quantum Dots by McMurry Deoxygenation Coupling.

    Science.gov (United States)

    Chen, Limei; Hu, Peiguang; Lu, Jia En; Chen, Shaowei

    2017-05-04

    Graphene quantum dots were covalently crosslinked forming ensembles of a few hundred nanometers in size by McMurry deoxygenation coupling reactions of peripheral carbonyl functional moieties catalyzed by TiCl4 and Zn powders in refluxing THF, as evidenced by TEM, AFM, FTIR, Raman and XPS measurements. Photoluminescence measurements showed that after chemical coupling, the excitation and emission peaks blue-shifted somewhat and the emission intensity increased markedly, likely due to the removal of oxygenated species where quinone-like species are known to be effective electron acceptors and emission quenchers. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Preparation of carbon quantum dots based on starch and their spectral properties.

    Science.gov (United States)

    Yan, Zhengyu; Shu, Juan; Yu, Yan; Zhang, Zhengwei; Liu, Zhen; Chen, Jianqiu

    2015-06-01

    A simple method for the synthesis of water-soluble carbon quantum dots (CQDs) has been developed based on chemical oxidation of starch. The structures and optical properties of the CQDs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, photoluminescence spectroscopy (PL) and transmission electron microscopy. The CQDs were found to emit bright blue fluorescence and disperse uniformly. The effects of ambient temperature, light and pH on the properties of CQDs were studied. The CQDs exhibited good chemical stability, good photostability and pH sensitivity. Furthermore, the interaction between CQDs and bovine serum albumin (BSA) was investigated. Copyright © 2014 John Wiley & Sons, Ltd.

  14. Adiabatic pumping through interacting quantum dots

    OpenAIRE

    Splettstoesser, Janine; Governale, Michele; König, Jürgen; Fazio, Rosario

    2005-01-01

    We present a general formalism to study adiabatic pumping through interacting quantum dots. We derive a formula that relates the pumped charge to the local, instantaneous Green function of the dot. This formula is then applied to the infinite-U Anderson model both for weak and strong tunnel-coupling strengths.

  15. Semiconductor quantum-dot lasers and amplifiers

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher; Borri, Paola; Ledentsov, N. N.

    2002-01-01

    We have produced GaAs-based quantum-dot edge-emitting lasers operating at 1.16 mu m with record-low transparency current, high output power, and high internal quantum efficiencies. We have also realized GaAs-based quantum-dot lasers emitting at 1.3 mu m, both high-power edge emitters and low...

  16. Thick-shell nanocrystal quantum dots

    Science.gov (United States)

    Hollingsworth, Jennifer A [Los Alamos, NM; Chen, Yongfen [Eugene, OR; Klimov, Victor I [Los Alamos, NM; Htoon, Han [Los Alamos, NM; Vela, Javier [Los Alamos, NM

    2011-05-03

    Colloidal nanocrystal quantum dots comprising an inner core having an average diameter of at least 1.5 nm and an outer shell, where said outer shell comprises multiple monolayers, wherein at least 30% of the quantum dots have an on-time fraction of 0.80 or greater under continuous excitation conditions for a period of time of at least 10 minutes.

  17. Optical Properties of Semiconductor Quantum Dots

    NARCIS (Netherlands)

    Perinetti, U.

    2011-01-01

    This thesis presents different optical experiments performed on semiconductor quantum dots. These structures allow to confine a small number of electrons and holes to a tiny region of space, some nm across. The aim of this work was to study the basic properties of different types of quantum dots

  18. Quantum Dots Coupled to a Superconductor

    DEFF Research Database (Denmark)

    Jellinggaard, Anders Robert

    are tuned electrostatically. This includes tuning the odd occupation of the dot through a quantum phase transition, where it forms a singlet with excitations in the superconductor. We detail the fabrication of these bottom gated devices, which additionally feature ancillary sensor dots connected...

  19. Effect of temperature on quantum dots

    Indian Academy of Sciences (India)

    MAHDI AHMADI BORJI

    2017-07-12

    Jul 12, 2017 ... applications. Quantum dot semiconductor lasers, due to the discrete density of states, low threshold current and temperature dependence, high optical gain and quan- tum efficiency and high modulation speed, ... elastic properties of neighbour materials, lattice mis- match, and geometry of the quantum dot ...

  20. Surround-gated vertical nanowire quantum dots

    NARCIS (Netherlands)

    Van Weert, M.H.M.; Den Heijer, M.; Van Kouwen, M.P.; Algra, R.E.; Bakkers, E.P.A.M.; Kouwenhoven, L.P.; Zwiller, V.

    2010-01-01

    We report voltage dependent photoluminescence experiments on single indium arsenide phosphide (InAsP) quantum dots embedded in vertical surround-gated indium phosphide (InP) nanowires. We show that by tuning the gate voltage, we can access different quantum dot charge states. We study the

  1. Optical studies of capped quantum dots

    NARCIS (Netherlands)

    Wuister, S.F.

    2005-01-01

    This thesis describes the synthesis and spectroscopy of CdSe and CdTe semiconductor quantum dots (QDs). The first chapter gives an introduction into the unique size dependent properties of semiconductor quantum dots. Highly luminescent QDs of CdSe and CdTe were prepared via a high temperature method

  2. Many electron effects in semiconductor quantum dots

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 26; Issue 1. Many electron effects in ... Semiconductor quantum dots (QDs) exhibit shell structures, very similar to atoms. Termed as 'artificial atoms' by some, ... Our calculations have been performed in a three-dimensional quantum dot. We have carried out a study of ...

  3. Properties of Open Clusters Containing Blue Stragglers

    Science.gov (United States)

    Lee, Hyun-Uk; Chang, Heon-Young

    2017-06-01

    The presence of blue stragglers pose challenges to standard stellar evolution theory, in the sense that explaining their presence demands a complex interplay between stellar evolution and cluster dynamics. In the meantime, mass transfer in binary systems and stellar collisions are widely studied as a blue straggler formation channel. We explore properties of the Galactic open clusters where blue stragglers are found, in attempting to estimate the relative importance of these two favored processes, by comparing them with those resulting from open clusters in which blue stragglers are absent as of now. Unlike previous studies which require a sophisticated process in understanding the implication of the results, this approach is straightforward and has resulted in a supplementary supporting evidence for the current view on the blue straggler formation mechanism. Our main findings are as follows: (1) Open clusters in which blue stragglers are present have a broader distribution with respect to the Z-axis pointing towards the North Galactic Pole than those in which blue stragglers are absent. The probability that two distributions with respect to the Z-axis are drawn from the same distribution is 0.2%. (2) Average values of log_{10}(t) of the clusters with blue stragglers and those without blue stragglers are 8.58 ± 0.232 and 7.52 ± 0.285, respectively. (3) The clusters with blue stragglers tend to be relatively redder than the others, and are distributed broader in colors. (4) The clusters with blue stragglers are likely brighter than those without blue stragglers. (5) Finally, blue stragglers seem to form in condensed clusters rather than simply dense clusters. Hence, we conclude that mass transfer in binaries seems to be a relatively important physical mechanism of the generation of blue stragglers in open clusters, provided they are sufficiently old.

  4. Coherent control of quantum dots

    DEFF Research Database (Denmark)

    Johansen, Jeppe; Lodahl, Peter; Hvam, Jørn Märcher

    In recent years much effort has been devoted to the use of semiconductor quantum dotsystems as building blocks for solid-state-based quantum logic devices. One importantparameter for such devices is the coherence time, which determines the number ofpossible quantum operations. From earlier...... measurements the coherence time of the selfassembledquantum dots (QDs) has been reported to be limited by the spontaneousemission rate at cryogenic temperatures1.In this project we propose to alter the coherence time of QDs by taking advantage of arecent technique on modifying spontaneous emission rates...

  5. Exciton in closed and opened quantum dot

    Directory of Open Access Journals (Sweden)

    M.V.Tkach

    2007-01-01

    Full Text Available The theory of exciton spectrum in spherically symmetric states for the three- shell closed spherical quantum dot is proposed. The evolution of the exciton spectrum while varying the outer well thickness from zero (stationary spectrum of single closed spherical quantum dot to infinity (quasistationary spectrum of a single open spherical quantum dot is investigated. The mechanism of damping (semiwidth of quasistationary states due to the redistribution over the energy levels of probability of exciton location in the space of two inner shells of nanosystem is studied. It is shown that the three shell closed spherical quantum dot of a rather big thickness of the outer well quite sufficiently and exactly reflects the basic properties of the quasistationary exciton spectrum in a single open spherical quantum dot.

  6. Biocompatible Quantum Dots for Biological Applications

    Science.gov (United States)

    Rosenthal, Sandra J.; Chang, Jerry C.; Kovtun, Oleg; McBride, James R.; Tomlinson, Ian D.

    2011-01-01

    Semiconductor quantum dots are quickly becoming a critical diagnostic tool for discerning cellular function at the molecular level. Their high brightness, long-lasting, sizetunable, and narrow luminescence set them apart from conventional fluorescence dyes. Quantum dots are being developed for a variety of biologically oriented applications, including fluorescent assays for drug discovery, disease detection, single protein tracking, and intracellular reporting. This review introduces the science behind quantum dots and describes how they are made biologically compatible. Several applications are also included, illustrating strategies toward target specificity, and are followed by a discussion on the limitations of quantum dot approaches. The article is concluded with a look at the future direction of quantum dots. PMID:21276935

  7. Biocompatible quantum dots for biological applications.

    Science.gov (United States)

    Rosenthal, Sandra J; Chang, Jerry C; Kovtun, Oleg; McBride, James R; Tomlinson, Ian D

    2011-01-28

    Semiconductor quantum dots are quickly becoming a critical diagnostic tool for discerning cellular function at the molecular level. Their high brightness, long-lasting, size-tunable, and narrow luminescence set them apart from conventional fluorescence dyes. Quantum dots are being developed for a variety of biologically oriented applications, including fluorescent assays for drug discovery, disease detection, single protein tracking, and intracellular reporting. This review introduces the science behind quantum dots and describes how they are made biologically compatible. Several applications are also included, illustrating strategies toward target specificity, and are followed by a discussion on the limitations of quantum dot approaches. The article is concluded with a look at the future direction of quantum dots. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Hole spin relaxation in quantum dots

    Science.gov (United States)

    Woods, L. M.; Reinecke, T. L.; Kotlyar, R.

    2004-03-01

    We present results for relaxation of the spin of a hole in a cylindrical quantum dot due to acoustic phonon assisted spin flips at low temperatures with an applied magnetic field. The hole dispersion is calculated by numerical diagonalization of the Luttinger Hamiltonian and applying perturbation theory with respect to the magnetic field, and the hole-phonon coupling is described by the Bir-Pikus Hamiltonian. We find that the decoherence time for hole spins for dots ≲20 nm is on the order of 10-8 s. This is several orders smaller than the decoherence time due to phonon assisted processes for electron spins in similar dots and is comparable to the total decoherence time of an electron spin in a quantum dot, which is controlled by the hyperfine interaction with nuclei. We obtain the dependence of the relaxation rate of the hole spin on dot size and hole mass.

  9. Adsorption of Methylene Blue, Bromophenol Blue, and Coomassie Brilliant Blue by α-chitin nanoparticles.

    Science.gov (United States)

    Dhananasekaran, Solairaj; Palanivel, Rameshthangam; Pappu, Srinivasan

    2016-01-01

    Expelling of dyestuff into water resource system causes major thread to the environment. Adsorption is the cost effective and potential method to remove the dyes from the effluents. Therefore, an attempt was made to study the adsorption of dyestuff (Methylene Blue (MB), Bromophenol Blue (BPB) and Coomassie Brilliant Blue (CBB)) by α-chitin nanoparticles (CNP) prepared from Penaeus monodon (Fabricius, 1798) shell waste. On contrary to the most recognizable adsorption studies using chitin, this is the first study using unique nanoparticles of ⩽50 nm used for the dye adsorption process. The results showed that the adsorption process increased with increase in the concentration of CNP, contact time and temperature with the dyestuff, whereas the adsorption process decreased with increase in the initial dye concentration and strong acidic pH. The results from Fourier transform infrared (FTIR) spectroscopy confirmed that the interaction between dyestuff and CNP involved physical adsorption. The adsorption process obeys Langmuir isotherm (R (2) values were 0.992, 0.999 and 0.992 for MB, BPB and CBB, and RL value lies between 0 and 1 for all the three dyes) and pseudo second order kinetics (R (2) values were 0.996, 0.999 and 0.996 for MB, BPB and CBB) more effectively. The isotherm and kinetic models confirmed that CNP can be used as a suitable adsorbent material for the removal of dyestuff from effluents.

  10. Adsorption of Methylene Blue, Bromophenol Blue, and Coomassie Brilliant Blue by α-chitin nanoparticles

    Directory of Open Access Journals (Sweden)

    Solairaj Dhananasekaran

    2016-01-01

    Full Text Available Expelling of dyestuff into water resource system causes major thread to the environment. Adsorption is the cost effective and potential method to remove the dyes from the effluents. Therefore, an attempt was made to study the adsorption of dyestuff (Methylene Blue (MB, Bromophenol Blue (BPB and Coomassie Brilliant Blue (CBB by α-chitin nanoparticles (CNP prepared from Penaeus monodon (Fabricius, 1798 shell waste. On contrary to the most recognizable adsorption studies using chitin, this is the first study using unique nanoparticles of ⩽50 nm used for the dye adsorption process. The results showed that the adsorption process increased with increase in the concentration of CNP, contact time and temperature with the dyestuff, whereas the adsorption process decreased with increase in the initial dye concentration and strong acidic pH. The results from Fourier transform infrared (FTIR spectroscopy confirmed that the interaction between dyestuff and CNP involved physical adsorption. The adsorption process obeys Langmuir isotherm (R2 values were 0.992, 0.999 and 0.992 for MB, BPB and CBB, and RL value lies between 0 and 1 for all the three dyes and pseudo second order kinetics (R2 values were 0.996, 0.999 and 0.996 for MB, BPB and CBB more effectively. The isotherm and kinetic models confirmed that CNP can be used as a suitable adsorbent material for the removal of dyestuff from effluents.

  11. A simple turn on fluorescent sensor for the selective detection of thiamine using coconut water derived luminescent carbon dots.

    Science.gov (United States)

    Purbia, Rahul; Paria, Santanu

    2016-05-15

    In this study microwave-assisted hydrothermal method was used to prepare highly luminescent carbon dots (1-6 nm size) within a minute from tender coconut (Cocos nucifera) water. The synthesized carbon dots (C-dots) exhibit emission of blue and green lights while excited at 390 and 450 nm wavelengths, respectively. As an application, these C-dots were tested for a simple "turn on" fluorescent sensor for rapid detection of thiamine (vitamin B1). The detection of thiamine in human body is very important to prevent various diseases such as beriberi, neurological disorders, optic neuropathy, etc. The fluorescence emission intensity of C-dots quenches after addition of Cu(2+) ion and then again increases selectively (turn on) after the addition of thiamine. The fluorescence emission intensity enhancement of Cu(2+) ion modified C-dots in the presence of thiamine exhibits a linear relationship within the thiamine concentration range of 10-50 μM. The limit of detection was found to be 280 nM from this study. The selectivity of the detection was also tested in the presence of different organic molecules and inorganic ions (Ca(2+), Mg(2+), Na(+), K(+), Cl(-), SO4(2-), and NO3(-)) which are present in blood serum and urine and found to be almost no interference in the detection. Finally, to see the applicability in real samples a commercial vitamin capsule was tested and found less than 3% error in the detected concentration. The C-dots were also used for bioimaging of fungus and the results show they are also suitable for this application too. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Graphene quantum dots produced by exfoliation of intercalated graphite nanoparticles and their application for temperature sensors

    Science.gov (United States)

    Nguyen, Duy Khiem; Kim, TaeYoung

    2018-01-01

    Graphene quantum dots (GQDs) have received much attention as a new class of fluorescent materials due to their unique transport phenomena and broadband absorption. Here, we present a method to produce pristine blue-luminescent GQDs from graphite nanoparticles by the intercalation of graphite nanoparticles and subsequent exfoliation in liquids. The as-synthesized GQDs are composed of highly crystalline carbon rings and show uniform size distribution ranging from 3 to 4 nm with an average thickness of ∼1 nm. The GQDs exhibit an excitation-dependent blue photoluminescence with a quantum yield of 22.3%. Furthermore, the GQDs were explored as an active sensing material for temperature measurement. The GQD-based temperature sensors show high responsivity to temperature changes over the range 30-80 °C.

  13. Silicon quantum dots for optical applications

    Science.gov (United States)

    Wu, Jeslin J.

    Luminescent silicon quantum dots (SiQDs) are emerging as attractive materials for optoelectronic devices, third generation photovoltaics, and bioimaging. Their applicability in the real world is contingent on their optical properties and long-term environmental stability; and in biological applications, factors such as water solubility and toxicity must also be taken into consideration. The aforementioned properties are highly dependent on the QDs' surface chemistry. In this work, SiQDs were engineered for the respective applications using liquid-phase and gas-phase functionalization techniques. Preliminary work in luminescent downshifting for photovoltaic systems are also reported. Highly luminescent SiQDs were fabricated by grafting unsaturated hydrocarbons onto the surface of hydrogen-terminated SiQDs via thermal and photochemical hydrosilylation. An industrially attractive, all gas-phase, nonthermal plasma synthesis, passivation (aided by photochemical reactions), and deposition process was also developed to reduce solvent waste. With photoluminescence quantum yields (PLQYs) nearing 60 %, the alkyl-terminated QDs are attractive materials for optical applications. The functionalized SiQDs also exhibited enhanced thermal stability as compared to their unfunctionalized counterparts, and the photochemically-hydrosilylated QDs further displayed photostability under UV irradiation. These environmentally-stable SiQDs were used as luminescent downshifting layers in photovoltaic systems, which led to enhancements in the blue photoresponse of heterojunction solar cells. Furthermore, the QD films demonstrated antireflective properties, improving the coupling efficiency of sunlight into the cell. For biological applications, oxide, amine, or hydroxyl groups were grafted onto the surface to create water-soluble SiQDs. Luminescent, water-soluble SiQDs were produced in by microplasma treating the QDs in water. Stable QYs exceeding 50 % were obtained. Radical-based and

  14. Alteraciones psíquicas en niños con retinosis pigmentaria Psychical disorders in retinitis pigmentosa-affected children

    Directory of Open Access Journals (Sweden)

    Irene Quiñones Varela

    1999-12-01

    Full Text Available Se realizó un estudio observacional, transversal y descriptivo en niños diagnosticados con retinosis pigmentaria y atendidos en el Centro Provincial de Retinosis Pigmentaria de Camagüey, con el fin de determinar la frecuencia de alteraciones psíquicas en pacientes con retinosis pigmentaria, identificar los principales tipos de estas alteraciones y mostrar los principales síntomas que nos permiten diagnosticar cada una de las entidades. Se le aplicó una encuesta a cada paciente donde se recogieron síntomas psíquicos y se diagnosticaron entidades psicopatológicas. Se comprobó que la frecuencia de alteraciones psíquicas en los niños es de 77,77 % y que las principales entidades fueron: síntomas especiales, trastornos neuróticos y trastornos del aprendizaje.An observational, crosswise and descriptive study of children diagnosed with retinitis pigmentosa and cared for at the Provincial Center of Retinitis Pigmentosa in Camagüey was under taken to determine the frequency of psychic disorders in patients with this diseases, identify the main types of such disorders and show the principal symptoms that allow the diagnosis of each of these entities. A survey was made to each patient where psychical symptoms were collected and psychopathological entities were diagnosed. It was shown that the frequency of psychic disorders in children was 77,77 % and that the main problems were special symptoms, neurotic disorders and learning disorders.

  15. A new theoretical approach to the functional meaning of sleep and dreaming in humans based on the maintenance of ‘predictive psychic homeostasis’

    Science.gov (United States)

    Barlow, Peter W.; Baluška, František; Tonin, Paolo; Guescini, Michele; Leo, Giuseppina; Fuxe, Kjell

    2011-01-01

    Different theories have been put forward during the last decade to explain the functional meaning of sleep and dreaming in humans. In the present paper, a new theory is presented which, while taking advantage of these earlier theories, introduces the following new and original aspects:   • Circadian rhythms relevant to various organs of the body affect the reciprocal interactions which operate to maintain constancy of the internal milieu and thereby also affect the sleep/wakefulness cycle. Particular attention is given to the constancy of natraemia and osmolarity and to the permissive role that the evolution of renal function has had for the evolution of the central nervous system and its integrative actions. • The resetting of neuro-endocrine controls at the onset of wakefulness leads to the acquisition of new information and its integration within previously stored memories. This point is dealt with in relation to Moore-Ede’s proposal for the existence of a ’predictive homeostasis’. • The concept of ‘psychic homeostasis’ is introduced and is considered as one of the most important states since it is aimed at the well-being, or eudemonia, of the human psyche. Sleep and dreaming in humans are discussed as important functions for the maintenance of a newly proposed composite state: that of ‘predictive psychic homeostasis’. On the basis of these assumptions, and in accordance with the available neurobiological data, the present paper puts forward the novel hypothesis that sleep and dreaming play important functions in humans by compensating for psychic allostatic overloads. Hence, both consolatory dreams and disturbing nightmares can be part of the vis medicatrix naturae, the natural healing power, in this case, the state of eudemonia. PMID:22448302

  16. A new theoretical approach to the functional meaning of sleep and dreaming in humans based on the maintenance of 'predictive psychic homeostasis'.

    Science.gov (United States)

    Agnati, Luigi F; Barlow, Peter W; Baluška, František; Tonin, Paolo; Guescini, Michele; Leo, Giuseppina; Fuxe, Kjell

    2011-11-01

    Different theories have been put forward during the last decade to explain the functional meaning of sleep and dreaming in humans. In the present paper, a new theory is presented which, while taking advantage of these earlier theories, introduces the following new and original aspects:   • Circadian rhythms relevant to various organs of the body affect the reciprocal interactions which operate to maintain constancy of the internal milieu and thereby also affect the sleep/wakefulness cycle. Particular attention is given to the constancy of natraemia and osmolarity and to the permissive role that the evolution of renal function has had for the evolution of the central nervous system and its integrative actions. • The resetting of neuro-endocrine controls at the onset of wakefulness leads to the acquisition of new information and its integration within previously stored memories. This point is dealt with in relation to Moore-Ede's proposal for the existence of a 'predictive homeostasis'. • The concept of 'psychic homeostasis' is introduced and is considered as one of the most important states since it is aimed at the well-being, or eudemonia, of the human psyche. Sleep and dreaming in humans are discussed as important functions for the maintenance of a newly proposed composite state: that of 'predictive psychic homeostasis'. On the basis of these assumptions, and in accordance with the available neurobiological data, the present paper puts forward the novel hypothesis that sleep and dreaming play important functions in humans by compensating for psychic allostatic overloads. Hence, both consolatory dreams and disturbing nightmares can be part of the vis medicatrix naturae, the natural healing power, in this case, the state of eudemonia.

  17. Electron transport in quantum dots

    CERN Document Server

    2003-01-01

    When I was contacted by Kluwer Academic Publishers in the Fall of 200 I, inviting me to edit a volume of papers on the issue of electron transport in quantum dots, I was excited by what I saw as an ideal opportunity to provide an overview of a field of research that has made significant contributions in recent years, both to our understanding of fundamental physics, and to the development of novel nanoelectronic technologies. The need for such a volume seemed to be made more pressing by the fact that few comprehensive reviews of this topic have appeared in the literature, in spite of the vast activity in this area over the course of the last decade or so. With this motivation, I set out to try to compile a volume that would fairly reflect the wide range of opinions that has emerged in the study of electron transport in quantum dots. Indeed, there has been no effort on my part to ensure any consistency between the different chapters, since I would prefer that this volume instead serve as a useful forum for the...

  18. Chiral quantum dot based materials

    Science.gov (United States)

    Govan, Joseph; Loudon, Alexander; Baranov, Alexander V.; Fedorov, Anatoly V.; Gun'ko, Yurii

    2014-05-01

    Recently, the use of stereospecific chiral stabilising molecules has also opened another avenue of interest in the area of quantum dot (QD) research. The main goal of our research is to develop new types of technologically important quantum dot materials containing chiral defects, study their properties and explore their applications. The utilisation of chiral penicillamine stabilisers allowed the preparation of new water soluble white emitting CdS quantum nanostructures which demonstrated circular dichroism in the band-edge region of the spectrum. It was also demonstrated that all three types of QDs (D-, L-, and Rac penicillamine stabilised) show very broad emission bands between 400 and 700 nm due to defects or trap states on the surfaces of the nanocrystals. In this work the chiral CdS based quantum nanostructures have also been doped by copper metal ions and new chiral penicilamine stabilized CuS nanoparticles have been prepared and investigated. It was found that copper doping had a strong effect at low levels in the synthesis of chiral CdS nanostructures. We expect that this research will open new horizons in the chemistry of chiral nanomaterials and their application in biotechnology, sensing and asymmetric synthesis.

  19. Quantum dots: lasers and amplifiers

    CERN Document Server

    Bimberg, D

    2003-01-01

    Continuous wave room-temperature output power of approx 3 W for edge emitters and of 1.2 mW for vertical-cavity surface-emitting lasers is realized for GaAs-based devices using InAs quantum dots (QDs) operating at 1.3 mu m. Characteristic temperatures up to 170 K below 330 K are realized. Simultaneously, differential efficiency exceeds 80% for these devices. Lasers emitting up to 12 W at 1140-1160 nm are useful as pump sources for Tm sup 3 sup + -doped fibres for frequency up-conversion to 470 nm. Both types of lasers show transparency current densities of 6 A cm sup - sup 2 per dot layer, eta sub i sub n sub t = 98% and alpha sub i around 1.5 cm sup - sup 1. Long operation lifetimes (above 3000 h at 50 deg C heatsink temperature at 1.5 W CW) and improved radiation hardness as compared to quantum well (QW) devices are manifested. Cut-off frequencies of about 10 GHz at 1100 nm and 6 GHz at 1300 nm and low alpha factors resulting in reduced filamentation and improved M sup 2 values in single-mode operation are ...

  20. Evaluation of Code Blue Implementation Outcomes

    Directory of Open Access Journals (Sweden)

    Bengü Özütürk

    2015-09-01

    Full Text Available Aim: In this study, we aimed to emphasize the importance of Code Blue implementation and to determine deficiencies in this regard. Methods: After obtaining the ethics committee approval, 225 patient’s code blue call data between 2012 and 2014 January were retrospectively analyzed. Age and gender of the patients, date and time of the call and the clinics giving Code Blue, the time needed for the Code Blue team to arrive, the rates of false Code Blue calls, reasons for Code Blue calls and patient outcomes were investigated. Results: A total of 225 patients (149 male, 76 female were evaluated in the study. The mean age of the patients was 54.1 years. 142 (67.2% Code Blue calls occurred after hours and by emergency unit. The mean time for the Code Blue team to arrive was 1.10 minutes. Spontaneous circulation was provided in 137 patients (60.8%; 88 (39.1% died. The most commonly identified possible causes were of cardiac origin. Conclusion: This study showed that Code Blue implementation with a professional team within an efficient and targeted time increase the survival rate. Therefore, we conclude that the application of Code Blue carried out by a trained team is an essential standard in hospitals. (The Medical Bulletin of Haseki 2015; 53:204-8

  1. Fire Whirls, Vortex Breakdown(?), and Blue Whirls

    Science.gov (United States)

    Oran, Elaine; Xiao, Huahua; Gollner, Michael

    2016-11-01

    As we were investigating the efficiency of fire-whirl burning on water, we observed the usual transformation of a pool fire to a fire whirl, and then suddenly, we saw the fire undergo a third transition. A blue cup appeared around the base of the fire whirl, surrounding the yellow flame, the yellow flame receded into the cup and finally disappeared. What remained was a small, rapidly spinning blue flame that burned until the fuel on the water was consumed. The blue whirl was shaped like a spinning cup, closed at the bottom near the water surface, and spreading in radius moving upwards towards the rim. Above the blue cup lip, there was a purple cone-shaped mist. The fuel was usually n-heptane, but at one point it was crude oil, and still the blue whirl formed naturally. The height of the fire whirl on the laboratory pan was larger than a half meter, and this evolved into a blue whirl about 4-8 cm high. Occasionally the blue whirl would become "unstable" and revert to a transitional state of blue cup holding a yellow flame. When the blue whirl formed, turbulence seemed to disappear, and the flame became quiet. We will show videos of how this happened and discuss the evolution of the fire whirl to the blue whirl in vortex-breakdown concepts. This work was supported by and EAGER award from NSF and Minta Martin Endowment Funds in the Department of Aerospace Engineering at the University of Maryland.

  2. Peptide dot immunoassay and immunoblotting: electroblotting from aluminum thin-layer chromatography plates and isoelectric focusing gels to activated nitrocellulose

    DEFF Research Database (Denmark)

    Bjerrum, O.J.; Holm, A.; Lauritzen, Edgar

    1993-01-01

    Peptide dot immunoassay, electroblotting, activated nitrocellulose, dot blot, membranes, peptides and proteins......Peptide dot immunoassay, electroblotting, activated nitrocellulose, dot blot, membranes, peptides and proteins...

  3. Being or having a body? The problem between the psychic and the somatic from the point of view of the Freudian metapsychology

    Directory of Open Access Journals (Sweden)

    Ligia Maria Durski

    2014-07-01

    Full Text Available The Freudian metapsychology brings us many grateful reflexions about the relations between the psychic apparatus and the organic body. These reflections are pertinent to the advancement of researches that need a greater understanding on the classic dichotomy “Body X Mind”. Therefore, this article accomplish some notes about such subject from the demonstration of the theoretical changes that Freud passed through along his work, especially about the human development in its psych and somatic sides. That being, we decided to organize this text following the path of the Freudian pulsional theory, prioritizing mainly the economical aspect of Freud’s metapsychology.

  4. Liquid biofuels from blue biomass

    DEFF Research Database (Denmark)

    Kádár, Zsófia; Jensen, Annette Eva; Bangsø Nielsen, Henrik

    2011-01-01

    Marine (blue) biomasses, such as macroalgaes, represent a huge unexploited amount of biomass. With their various chemical compositions, macroalgaes can be a potential substrate for food, feed, biomaterials, pharmaceuticals, health care products and also for bioenergy. Algae use seawater as a growth...... medium, light as energy source and they capture CO2 for the synthesis of new organic material, thus can grow on non-agricultural land, without increasing food prices, or using fresh water. Due to all these advantages in addition to very high biomass yield with high carbohydrate content, macroalgaes can...

  5. Melanoma and Satellite Blue Papule

    OpenAIRE

    Oliveira, A.; Arzberger, E; Massone, C.; Zalaudek, I.; Fink-Puches, R; Hofmann-Wellenhof, R

    2014-01-01

    The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slo...

  6. Blue breath holding is benign.

    Science.gov (United States)

    Stephenson, J B

    1991-01-01

    In their recent publication in this journal, Southall et al described typical cyanotic breath holding spells, both in otherwise healthy children and in those with brainstem lesions and other malformations. Their suggestions regarding possible autonomic disturbances may require further study, but they have adduced no scientific evidence to contradict the accepted view that in the intact child blue breath holding spells are benign. Those families in which an infant suffers an 'apparently life threatening event' deserve immense understanding and help, and it behoves investigators to exercise extreme care and self criticism in the presentation of new knowledge which may bear upon their management and their morale. PMID:2001115

  7. Inter-dot coupling effects on transport through correlated parallel ...

    Indian Academy of Sciences (India)

    Transport through symmetric parallel coupled quantum dot system has been studied, using non-equilibrium Green function formalism. The inter-dot tunnelling with on-dot and inter-dot Coulomb repulsion is included. The transmission coefficient and Landaur–Buttiker like current formula are shown in terms of internal states ...

  8. Quantum dots with single-atom precision.

    Science.gov (United States)

    Fölsch, Stefan; Martínez-Blanco, Jesús; Yang, Jianshu; Kanisawa, Kiyoshi; Erwin, Steven C

    2014-07-01

    Quantum dots are often called artificial atoms because, like real atoms, they confine electrons to quantized states with discrete energies. However, although real atoms are identical, most quantum dots comprise hundreds or thousands of atoms, with inevitable variations in size and shape and, consequently, unavoidable variability in their wavefunctions and energies. Electrostatic gates can be used to mitigate these variations by adjusting the electron energy levels, but the more ambitious goal of creating quantum dots with intrinsically digital fidelity by eliminating statistical variations in their size, shape and arrangement remains elusive. We used a scanning tunnelling microscope to create quantum dots with identical, deterministic sizes. By using the lattice of a reconstructed semiconductor surface to fix the position of each atom, we controlled the shape and location of the dots with effectively zero error. This allowed us to construct quantum dot molecules whose coupling has no intrinsic variation but could nonetheless be tuned with arbitrary precision over a wide range. Digital fidelity opens the door to quantum dot architectures free of intrinsic broadening-an important goal for technologies from nanophotonics to quantum information processing as well as for fundamental studies of confined electrons.

  9. Electronic properties of blue phosphorene/graphene and blue phosphorene/graphene-like gallium nitride heterostructures.

    Science.gov (United States)

    Sun, Minglei; Chou, Jyh-Pin; Yu, Jin; Tang, Wencheng

    2017-07-05

    Blue phosphorene (BlueP) is a graphene-like phosphorus nanosheet which was synthesized very recently for the first time [Nano Lett., 2016, 16, 4903-4908]. The combination of electronic properties of two different two-dimensional materials in an ultrathin van der Waals (vdW) vertical heterostructure has been proved to be an effective approach to the design of novel electronic and optoelectronic devices. Therefore, we used density functional theory to investigate the structural and electronic properties of two BlueP-based heterostructures - BlueP/graphene (BlueP/G) and BlueP/graphene-like gallium nitride (BlueP/g-GaN). Our results showed that the semiconducting nature of BlueP and the Dirac cone of G are well preserved in the BlueP/G vdW heterostructure. Moreover, by applying a perpendicular electric field, it is possible to tune the position of the Dirac cone of G with respect to the band edge of BlueP, resulting in the ability to control the Schottky barrier height. For the BlueP/g-GaN vdW heterostructure, BlueP forms an interface with g-GaN with a type-II band alignment, which is a promising feature for unipolar electronic device applications. Furthermore, we discovered that both G and g-GaN can be used as an active layer for BlueP to facilitate charge injection and enhance the device performance.

  10. Geothermal Technologies Program Blue Ribbon Panel Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-06-17

    The Geothermal Technologies Program assembled a geothermal Blue Ribbon Panel on March 22-23, 2011 in Albuquerque, New Mexico for a guided discussion on the future of geothermal energy in the United States and the role of the DOE Program. The Geothermal Blue Ribbon Panel Report captures the discussions and recommendations of the experts. An addendum is available here: http://www.eere.energy.gov/geothermal/pdfs/gtp_blue_ribbon_panel_report_addendum10-2011.pdf

  11. Photodynamic therapy with Methylene Blue as photosensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Nishisaka, Tsuyoshi (Tokyo Univ. of Agriculture and Technology, Fuchu, Tokyo (Japan). Health Science Center); Ennyu, Hiroko; Takeno, Tetsu; Okura, Ichiro

    1993-07-01

    Availability of Methylene Blue as a photosensitizer in photodynamic therapy was investigated, and it was found that the HeLa cells incorporated with Methylene Blue was strongly damaged by the irradiation with laser light. Methylene Blue was effective for the irradiation of longer wavelength, which has the large tissue penetration depth. The possible reaction mechanism of the cell damage via photo-produced singlet oxygen is discussed. (author).

  12. Investigation on DOT guided FMT: Whether the FMT image quality is robust to the priori DOT information?

    Science.gov (United States)

    Wang, Daifa; Bai, Jing

    2009-01-01

    The fluorescence molecular tomography (FMT) image quality could be improved significantly with reconstructed optical properties using diffuse optical tomography (DOT). However, different DOT algorithms and different constraint parameters usually lead to DOT images of obvious different image quality. In this paper, simulation experiment results demonstrate that the FMT image quality is robust to the great variation in DOT image quality.

  13. X-H{center_dot}{center_dot}{center_dot}{pi} and X-H{center_dot}{center_dot}{center_dot}N hydrogen bonds - Acetylene and hydrogen cyanide as proton acceptors

    Energy Technology Data Exchange (ETDEWEB)

    Domagala, Malgorzata, E-mail: mdomagala@uni.lodz.pl [Department of Chemistry, University of Lodz, ul.Pomorska 149/153, 90-236 Lodz (Poland); Grabowski, Slawomir J., E-mail: slagra@uni.lodz.pl [Department of Chemistry, University of Lodz, ul.Pomorska 149/153, 90-236 Lodz (Poland)

    2009-09-18

    The hydrogen-bonded systems were considered where acetylene or hydrogen cyanide acts as a proton acceptor and different proton donating molecules are taken into account. The B3LYP/6-311++G(d,p) and MP2/6-311++G(d,p) calculations were performed for the systems considered; for HCN{center_dot}{center_dot}{center_dot}HF and C{sub 2}H{sub 2}{center_dot}{center_dot}{center_dot}HF complexes various levels of approximation were applied up to CCSD(T)/6-311++G(3df,3pd)//CCSD/6-311++G(3df,3pd). The Quantum Theory of 'Atoms in Molecules' (QTAIM) was also applied. It was found that {pi}-electrons of acetylene might act as the proton accepting centers and the found complex conformations are T-shaped ones. For hydrogen cyanide molecule the nitrogen atom acts as the proton acceptor center but not {pi}-electrons. The characteristics of the bond critical points were also considered for the analyzed interactions and numerous correlations were found between geometrical, energetic and QTAIM parameters. The decomposition of the interaction energy for the systems analyzed was also applied.

  14. Parapsychology: The Psychic World

    Science.gov (United States)

    White, Rhea A.

    1972-01-01

    Books on parapsychology are reviewed to provide a general orientation to the subject, to indicate the best current sources of information, and to recommend a basic library collection on parapsychology. (69 references) (SJ)

  15. Moment of inertia in elliptical quantum dots

    Science.gov (United States)

    Serra, Llorenç; Puente, Antonio; Lipparini, Enrico

    The moment of inertia of deformed quantum dots and its experimental relevance in relation to the dot spectroscopic features is theoretically investigated. A strong link to the low-energy orbital current mode that manifests in the magnetic dipole (M1) spectrum is stressed. The moment of inertia is obtained by solving the cranked Kohn-Sham equations within the local-spin-density approximation and the results discussed in comparison with the predictions of an analytical non-interacting model. The results as a function of deformation and size indicate that the existence of spin transitions in the dot ground state has an important effect on the moment of inertia.

  16. Odd triplet superconductivity in ultrasmall quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Stephan; Koenig, Juergen [Theoretische Physik, Universitaet Duisburg-Essen and CENIDE (Germany); Sothmann, Bjoern [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg (Germany)

    2016-07-01

    We report on the possibility to create odd frequency Cooper pairs in proximized interacting quantum dots attached to ferromagnetic leads. Spin blockade effects together with induced superconductivity allow electron pairs with same spin at different times to carry superconducting correlations. Besides the conventional finite singlet pairing amplitude on the dot, only odd frequency triplet pairing is possible here. This is in contrast to the double dot case. We demonstrate how the order parameter for odd-frequency triplet pairing as well as the differential Andreev conductance are influenced when tuning gate and/or bias voltages, the angle of magnetizations of the leads and the coupling to the nearby superconductor.

  17. Excitonic quasimolecules in nanosystems of quantum dots

    Science.gov (United States)

    Pokutnyi, Sergey I.

    2017-09-01

    The theory of excitonic quasimolecules (biexcitons) (formed of spatially separated electrons and holes) in a nanosystem that consists of semiconductor quantum dots synthesized in a borosilicate glass matrix is presented. It is shown that exciton quasimolecule formation is of a threshold character and is possible in nanosystem, if the spacing between the quantum dots surfaces is larger than a certain critical spacing. It was found that the binding energy of the singlet ground state of an exciton quasimolecule, consisting of two semiconductor quantum dots is a significant large values, larger than the binding energy of the biexciton in a semiconductor single crystal by almost two orders of magnitude.

  18. Fluorescent Quantum Dots for Biological Labeling

    Science.gov (United States)

    McDonald, Gene; Nadeau, Jay; Nealson, Kenneth; Storrie-Lomardi, Michael; Bhartia, Rohit

    2003-01-01

    Fluorescent semiconductor quantum dots that can serve as "on/off" labels for bacteria and other living cells are undergoing development. The "on/off" characterization of these quantum dots refers to the fact that, when properly designed and manufactured, they do not fluoresce until and unless they come into contact with viable cells of biological species that one seeks to detect. In comparison with prior fluorescence-based means of detecting biological species, fluorescent quantum dots show promise for greater speed, less complexity, greater sensitivity, and greater selectivity for species of interest. There are numerous potential applications in medicine, environmental monitoring, and detection of bioterrorism.

  19. Analysis list: DOT1L [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DOT1L Pluripotent stem cell + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/DOT1...L.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/DOT1L.5.tsv http://dbarchive.biosc...iencedbc.jp/kyushu-u/hg19/target/DOT1L.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/DOT1L.Plu

  20. Parallel carbon nanotube quantum dots and their interactions

    OpenAIRE

    Goss K.; Leijnse M.; Smerat S.; Wegewijs M.R.; Schneider C.M.; Meyer C

    2012-01-01

    We present quantum transport measurements of interacting parallel quantum dots formed in the strands of a carbon nanotube rope. In this molecular quantum dot system, transport is dominated by one quantum dot, while additional resonances from parallel side dots appear, which exhibit a weak gate coupling. This differential gating effect provides a tunability of the quantum dot system with only one gate electrode and provides control over the carbon nanotube strand that carries the current. By t...

  1. Scanning gate microscopy of ultra clean carbon nanotube quantum dots

    OpenAIRE

    Xue, Jiamin; Dhall, Rohan; Cronin, Stephen B.; LeRoy, Brian J.

    2015-01-01

    We perform scanning gate microscopy on individual suspended carbon nanotube quantum dots. The size and position of the quantum dots can be visually identified from the concentric high conductance rings. For the ultra clean devices used in this study, two new effects are clearly identified. Electrostatic screening creates non-overlapping multiple sets of Coulomb rings from a single quantum dot. In double quantum dots, by changing the tip voltage, the interactions between the quantum dots can b...

  2. Formations of magnetic vortices in a chain array of triangle Py dots and an isosceles triangle Py dot

    Science.gov (United States)

    Miyata, M.; Kiseki, K.; Yakata, S.; Wada, H.; Kimura, T.

    2012-04-01

    We have studied the magnetic domain structures in a magneto-statically-coupled chain array of the triangle dots and an isosceles triangle dot by means of magnetic force microscopy (MFM). Despite the strong magneto-static interaction in the chain array of the dots, each triangle dot takes a single vortex structure. The chirality of each dot is found to behave similarly to that for the isolated triangle dot. We also demonstrated that single-vortex and double-vortex structures with the desired chiralities can be stabilized in an isosceles triangle dot.

  3. Thermoelectric transport through quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Merker, Lukas Heinrich

    2016-06-30

    In this thesis the thermoelectric properties (electrical conductance, Seebeck coefficient and thermal conductance)of quantum dots described by the Anderson impurity model have been investigated by using the numerical renormalization group (NRG) method. In order to make accurate calculations for thermoelectric properties of quantum impurity systems, a number of recent developments and refinements of the NRG have been implemented. These include the z-averaging and Campo discretization scheme, which enable the evaluation of physical quantities on an arbitrary temperature grid and at large discretization parameter Λ and the full density matrix (FDM) approach, which allows a more accurate calculation of spectral functions and transport coefficients. The implementation of the z-averaging and Campo discretization scheme has been tested within a new method for specific heats of quantum impurities. The accuracy of this new method was established by comparison with the numerical solution of the Bethe-ansatz equations for the Anderson model. The FDM approach was implemented and tested within a new approach to the calculation of impurity contributions to the uniform susceptibilities. Within this method a non-negligible contribution from the ''environmental'' degrees of freedom needs to be taken into account to recover the correct susceptibility, as shown by comparison with the Bethe-ansatz approach. An accurate method to calculate the conductance of a quantum dot is implemented, enabling the extraction of the Fermi liquid scaling coefficients c{sub T} and c{sub B} to high accuracy, being able to verify the results of the renormalized super perturbation theory approach (within its regime of validity). The method was generalized to higher order moments of the local level spectral function. This, as well as reduction of the SU(2) code to the U(1) symmetry, enabled the investigation of the effect of a magnetic field on the thermoelectric properties of quantum

  4. Phonon impact on optical control schemes of quantum dots: Role of quantum dot geometry and symmetry

    Science.gov (United States)

    Lüker, S.; Kuhn, T.; Reiter, D. E.

    2017-12-01

    Phonons strongly influence the optical control of semiconductor quantum dots. When modeling the electron-phonon interaction in several theoretical approaches, the quantum dot geometry is approximated by a spherical structure, though typical self-assembled quantum dots are strongly lens-shaped. By explicitly comparing simulations of a spherical and a lens-shaped dot using a well-established correlation expansion approach, we show that, indeed, lens-shaped dots can be exactly mapped to a spherical geometry when studying the phonon influence on the electronic system. We also give a recipe to reproduce spectral densities from more involved dots by rather simple spherical models. On the other hand, breaking the spherical symmetry has a pronounced impact on the spatiotemporal properties of the phonon dynamics. As an example we show that for a lens-shaped quantum dot, the phonon emission is strongly concentrated along the direction of the smallest axis of the dot, which is important for the use of phonons for the communication between different dots.

  5. Fabrication of highly fluorescent graphene quantum dots using L-glutamic acid for in vitro/in vivo imaging and sensing

    OpenAIRE

    Wu, Xu; Tian, Fei; Wang, Wenxue; Chen, Jiao; Wu, Min; Zhao, Julia Xiaojun

    2013-01-01

    A facile bottom-up method for the synthesis of highly fluorescent graphene quantum dots (GQDs) has been developed using a one-step pyrolysis of a natural amino acid, L-glutamic acid, with the assistance of a simple heating mantle device. The developed GQDs showed strong blue, green and red luminescence under the irradiation of ultra-violet, blue and green light, respectively. Moreover, the GQDs emitted near-infrared (NIR) fluorescence in the range of 800–850 nm with the excitation-dependent m...

  6. IMPRESS YOUR FRIENDS AND PREDICT THE FINAL SCORE: An analysis of the psychic ability of four target resetting methods used in One-Day International Cricket

    Directory of Open Access Journals (Sweden)

    Barbara J. O'Riley

    2006-12-01

    Full Text Available One-Day cricket's eternal problem is how to fairly account for an interruption that occurs during a team's innings. Several methods have been applied in the past, some more successfully than others. Numerous articles have been written about different target resetting methods applicable in one-day international cricket and how they "favour" one team over another. In this paper we use an alternative approach looking at the psychic ability of four target resetting methods and compare how well they predict the final score based on the present state of the first innings. We attempt to convert each of methods we investigate into a ball-by-ball predictive tool. We introduce a terminal interruption to the first innings at every ball and compute the predicted final score. We ascribe a nominal value to the difference between the final achieved score and the prediction given by each method. We compute our own 'Psychic Metric' to enable a comparison between the four methods. We also develop a computer package to manipulate the data from matches in which the first innings was completed

  7. Quantum Dot Light Enhancement Substrate for OLED Solid-State Lighting

    Energy Technology Data Exchange (ETDEWEB)

    James Perkins; Matthew Stevenson; Gagan Mahan; Seth Coe-Sullivan; Peter Kazlas

    2011-01-21

    With DOE Award No. DE-EE00000628, QD Vision developed and demonstrated a cost-competitive solution for increasing the light extraction efficiency of OLEDs with efficient and stable color rendering index (CRI) for solid state lighting (SSL). Solution processable quantum dot (QD) films were integrated into OLED ITO-glass substrates to generate tunable white emission from blue emitting OLED) devices as well as outcouple light from the ITO film. This QD light-enhancement substrate (QD-LED) technology demonstrated a 60% increase in OLED forward light out-coupling, a value which increases to 76% when considering total increase in multi-directional light output. The objective for the first year was an 80% increase in light output. This project seeks to develop and demonstrate a cost-competitive solution for realizing increased extraction efficiency organic light emitting devices (OLEDs) with efficient and stable color rendering index (CRI) for SSL. Solution processible quantum dot (QD) films will be utilized to generate tunable white emission from blue emitting phosphorescent OLED (Ph-OLED) devices.

  8. Quantum Phase Transitions in Quantum Dots

    OpenAIRE

    Rau, I. G.; Amasha, S.; Oreg, Y.; Goldhaber-Gordon, D.

    2013-01-01

    This review article describes theoretical and experimental advances in using quantum dots as a system for studying impurity quantum phase transitions and the non-Fermi liquid behavior at the quantum critical point.

  9. Double quantum dots defined in bilayer graphene

    Science.gov (United States)

    Żebrowski, D. P.; Peeters, F. M.; Szafran, B.

    2017-07-01

    Artificial molecular states of double quantum dots defined in bilayer graphene are studied with the atomistic tight-binding method and its low-energy continuum approximation. We indicate that the extended electron wave functions have opposite parities on sublattices of the layers and that the ground-state wave-function components change from bonding to antibonding with the interdot distance. In the weak-coupling limit, the one most relevant for quantum dots defined electrostatically, the signatures of the interdot coupling include, for the two-electron ground state, formation of states with symmetric or antisymmetric spatial wave functions split by the exchange energy. In the high-energy part of the spectrum the states with both electrons in the same dot are found with the splitting of energy levels corresponding to simultaneous tunneling of the electron pair from one dot to the other.

  10. Large quantum dots with small oscillator strength

    DEFF Research Database (Denmark)

    Stobbe, Søren; Schlereth, T.W.; Höfling, S.

    2010-01-01

    We have measured the oscillator strength and quantum efficiency of excitons confined in large InGaAs quantum dots by recording the spontaneous emission decay rate while systematically varying the distance between the quantum dots and a semiconductor-air interface. The size of the quantum dots...... is measured by in-plane transmission electron microscopy and we find average in-plane diameters of 40 nm. We have calculated the oscillator strength of excitons of that size assuming a quantum-dot confinement given by a parabolic in-plane potential and a hard-wall vertical potential and predict a very large...... oscillator strength due to Coulomb effects. This is in stark contrast to the measured oscillator strength, which turns out to be so small that it can be described by excitons in the strong confinement regime. We attribute these findings to exciton localization in local potential minima arising from alloy...

  11. Ge Quantum Dot Infrared Imaging Camera Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations Incorporated proposes to develop a high performance Ge quantum dots-based infrared (IR) imaging camera on Si substrate. The high sensitivity, large...

  12. Carbon Quantum Dots for Zebrafish Fluorescence Imaging

    National Research Council Canada - National Science Library

    Kang, Yan-Fei; Li, Yu-Hao; Fang, Yang-Wu; Xu, Yang; Wei, Xiao-Mi; Yin, Xue-Bo

    2015-01-01

    Carbon quantum dots (C-QDs) are becoming a desirable alternative to metal-based QDs and dye probes owing to their high biocompatibility, low toxicity, ease of preparation, and unique photophysical properties...

  13. Preparation and Application of Fluorescent Carbon Dots

    National Research Council Canada - National Science Library

    Zuo, Jun; Jiang, Tao; Zhao, Xiaojing; Xiong, Xiaohong; Xiao, Saijin; Zhu, Zhiqiang

    2015-01-01

      Fluorescent carbon dots (CDs) are a novel type of fluorescent nanomaterials, which not only possess the specific quantum confinement effects of nanomaterials due to the small size of nanomaterials, but also have good...

  14. Nanomaterials: Earthworms lit with quantum dots

    Science.gov (United States)

    Tilley, Richard D.; Cheong, Soshan

    2013-01-01

    Yeast, bacteria and fungi have been used to synthesize a variety of nanocrystals. Now, the metal detoxification process in the gut of an earthworm is exploited to produce biocompatible cadmium telluride quantum dots.

  15. Methylthymol blue in Fricke gels

    Science.gov (United States)

    Penev, K. I.; Mequanint, K.

    2015-01-01

    The initial trial of methylthymol blue (MTB) as a chelator for ferric iron in Fricke gel dosimeters, used for three-dimensional (3D) dosimetry in cancer radiotherapy, is reported. MTB is a structural analogue of the conventionally used xylenol orange (XO); however, the absorbance spectrum of the ferric-MTB complex is shifted to higher wavelengths, which should allow for lower amount of light scattering during gel scanning. In this study, two gelatin substrates, two sources of XO and one source of MTB have been compared. The MTB- containing gels exhibited similar dose response and diffusion coefficient to the XO-containing gels at their wavelengths of maximum absorption (620 and 585 nm, respectively). In addition, the MTB gels gave an excellent dose response at 633 nm, which is an important wavelength that is already used with other 3D dosimeters.

  16. Dot Display Affects Approximate Number System Acuity and Relationships with Mathematical Achievement and Inhibitory Control.

    Science.gov (United States)

    Norris, Jade Eloise; Castronovo, Julie

    2016-01-01

    Much research has investigated the relationship between the Approximate Number System (ANS) and mathematical achievement, with continued debate surrounding the existence of such a link. The use of different stimulus displays may account for discrepancies in the findings. Indeed, closer scrutiny of the literature suggests that studies supporting a link between ANS acuity and mathematical achievement in adults have mostly measured the ANS using spatially intermixed displays (e.g. of blue and yellow dots), whereas those failing to replicate a link have primarily used spatially separated dot displays. The current study directly compared ANS acuity when using intermixed or separate dots, investigating how such methodological variation mediated the relationship between ANS acuity and mathematical achievement. ANS acuity was poorer and less reliable when measured with intermixed displays, with performance during both conditions related to inhibitory control. Crucially, mathematical achievement was significantly related to ANS accuracy difference (accuracy on congruent trials minus accuracy on incongruent trials) when measured with intermixed displays, but not with separate displays. The findings indicate that methodological variation affects ANS acuity outcomes, as well as the apparent relationship between the ANS and mathematical achievement. Moreover, the current study highlights the problem of low reliabilities of ANS measures. Further research is required to construct ANS measures with improved reliability, and to understand which processes may be responsible for the increased likelihood of finding a correlation between the ANS and mathematical achievement when using intermixed displays.

  17. Dot Display Affects Approximate Number System Acuity and Relationships with Mathematical Achievement and Inhibitory Control.

    Directory of Open Access Journals (Sweden)

    Jade Eloise Norris

    Full Text Available Much research has investigated the relationship between the Approximate Number System (ANS and mathematical achievement, with continued debate surrounding the existence of such a link. The use of different stimulus displays may account for discrepancies in the findings. Indeed, closer scrutiny of the literature suggests that studies supporting a link between ANS acuity and mathematical achievement in adults have mostly measured the ANS using spatially intermixed displays (e.g. of blue and yellow dots, whereas those failing to replicate a link have primarily used spatially separated dot displays. The current study directly compared ANS acuity when using intermixed or separate dots, investigating how such methodological variation mediated the relationship between ANS acuity and mathematical achievement. ANS acuity was poorer and less reliable when measured with intermixed displays, with performance during both conditions related to inhibitory control. Crucially, mathematical achievement was significantly related to ANS accuracy difference (accuracy on congruent trials minus accuracy on incongruent trials when measured with intermixed displays, but not with separate displays. The findings indicate that methodological variation affects ANS acuity outcomes, as well as the apparent relationship between the ANS and mathematical achievement. Moreover, the current study highlights the problem of low reliabilities of ANS measures. Further research is required to construct ANS measures with improved reliability, and to understand which processes may be responsible for the increased likelihood of finding a correlation between the ANS and mathematical achievement when using intermixed displays.

  18. Synthesis and drug detection performance of nitrogen-doped carbon dots

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Jingjing [Functional and Environment Materials Research Institute, College of Physical Science and Technology, Lanzhou University, Lanzhou 730000 (China); Nano Structure and Low Dimensional Physics Laboratory, Peking University, Beijing 100871 (China); Gao, Hui, E-mail: hope@lzu.edu.cn [Functional and Environment Materials Research Institute, College of Physical Science and Technology, Lanzhou University, Lanzhou 730000 (China)

    2014-05-01

    Recently, nitrogen-doped carbon dots (NCDs) have attracted considerable interest since nitrogen (N) doping could effectively tailor the electronic properties and the chemical reactivity of carbon dots (CDs) for advanced potential applications. Herein, a one-step pyrolysis method was presented for synthesizing the NCDs with excellent water solubility, good stability and a high quantum yield of ca. 28%. The detection performance of NCDs for the antibacterial drugs was further explored, and it was proved to effectively enhance the fluorescence due to the strong interaction between the NCDs and antibacterial drugs. - Highlights: • A facile yet economic bottom-up pyrolysis method for synthesizing nitrogen (N)-doped carbon dots (NCDs) using glutamic acid as the precursor. • Glutamic acid was the only starting material and used as a source of carbon and nitrogen; the formation and functionalization of NCDs were accomplished simultaneously. • The NCDs possess bright blue emission (with a high quantum yield of ca. 28%) and excellent excitation dependent on PL properties. • NCDs were used for the determination of antibacterial drugs based on the fluorescence enhancement.

  19. Multicolor fluorescent light-emitting diodes based on cesium lead halide perovskite quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peng [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012 (China); Bai, Xue, E-mail: baix@jlu.edu.cn, E-mail: yuzhang@jlu.edu.cn; Sun, Chun; Zhang, Xiaoyu; Zhang, Yu, E-mail: baix@jlu.edu.cn, E-mail: yuzhang@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Zhang, Tieqiang [State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012 (China)

    2016-08-08

    High quantum yield, narrow full width at half-maximum and tunable emission color of perovskite quantum dots (QDs) make this kind of material good prospects for light-emitting diodes (LEDs). However, the relatively poor stability under high temperature and air condition limits the device performance. To overcome this issue, the liquid-type packaging structure in combination with blue LED chip was employed to fabricate the fluorescent perovskite quantum dot-based LEDs. A variety of monochromatic LEDs with green, yellow, reddish-orange, and red emission were fabricated by utilizing the inorganic cesium lead halide perovskite quantum dots as the color-conversion layer, which exhibited the narrow full width at half-maximum (<35 nm), the relatively high luminous efficiency (reaching 75.5 lm/W), and the relatively high external quantum efficiency (14.6%), making it the best-performing perovskite LEDs so far. Compared to the solid state LED device, the liquid-type LED devices exhibited excellent color stability against the various working currents. Furthermore, we demonstrated the potential prospects of all-inorganic perovskite QDs for the liquid-type warm white LEDs.

  20. Micromagnetic Simulations of Submicron Cobalt Dots

    Energy Technology Data Exchange (ETDEWEB)

    Parker, G.J.; Cerjan, C.

    1999-08-30

    Numerical simulations of submicron Co extruded elliptical dots were performed to illustrate the relative importance of different physical parameters on the switching behavior in the easy direction. Shape, size, magnetic moment magnitude and crystalline anisotropy, both magnitude and distribution, were varied. The simulation includes calculation of the magnetostatic, exchange and crystalline anisotropy fields on a structured mesh using finite difference techniques. The smooth boundary of the dots are accurately represented by use of the Embedded Curve Boundary method.

  1. Blue code: Is it a real emergency?

    Science.gov (United States)

    Eroglu, Serkan E; Onur, Ozge; Urgan, Oğuz; Denizbasi, Arzu; Akoglu, Haldun

    2014-01-01

    Cardiac arrests in hospital areas are common, and hospitals have rapid response teams or "blue code teams" to reduce preventable in-hospital deaths. Education about the rapid response team has been provided in all hospitals in Turkey, but true "blue code" activation is rare, and it is abused by medical personnel in practice. This study aimed to determine the cases of wrong blue codes and reasons of misuse. This retrospective study analyzed the blue code reports issued by our hospital between January 1 and June 1 2012. A total of 89 "blue code" activations were recorded in 5 months. A "blue code" was defined as any patient with an unexpected cardiac or respiratory arrest requiring resuscitation and activation of a hospital alert. Adherence to this definition, each physician classified their collected activation forms as either a true or a wrong code. Then, patient data entered a database (Microsoft Excel 2007 software) which was pooled for analysis. The data were analyzed by using frequencies and the Chi-square test on SPSSv16.0. The patients were diagnosed with cardiopulmonary arrest (8), change in mental status (18), presyncope (11), chest pain (12), conversive disorder (18), and worry of the staff for the patient (22). Code activation was done by physicians in 76% of the patients; the most common reason for blue code was concern of staff for the patient. The findings of this study show that more research is needed to establish the overall effectiveness and optimal implementation of blue code teams.

  2. Instituting code blue drills in the OR.

    Science.gov (United States)

    Lanfranchi, Joy A

    2013-04-01

    A code blue in the OR is a low-volume, high-risk event. To be effective during a code blue event, perioperative personnel must be able to properly execute a response plan and perform seldom-used skills and procedures. I developed and implemented a code blue drill educational experience for OR staff members that included a review of code blue policy, how to use a defibrillator, and simulated code blue scenarios. In addition, I worked with educational facilitators to provide an assessment of the personnel who performed the simulated code blue drills to identify key learning opportunities, such as gaps in communication, poor performance of cardiopulmonary resuscitation, ineffective delegation skills, and lack of assertiveness. One month after the educational experience, all team members passed an observed competency for responding to a code blue in a simulation laboratory. These results show the effectiveness of the educational experience as part of the code blue drills program in the hospital's main OR. Copyright © 2013 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  3. Blue Skies, Coffee Creamer, and Rayleigh Scattering

    Science.gov (United States)

    Liebl, Michael

    2010-01-01

    The first physical explanation of Earths blue sky was fashioned in 1871 by Lord Rayleigh. Many discussions of Rayleigh scattering and approaches to studying it both in and out of the classroom are available. Rayleigh scattering accounts for the blue color of the sky and the orange/red color of the Sun near sunset and sunrise, and a number of…

  4. Blue jay attacks and consumes cedar waxwing

    Science.gov (United States)

    Daniel Saenz; Joshua B. Pierce

    2009-01-01

    Blue Jays (Cyanocitta cristata) are known to be common predators on bird nests (Wilcove 1985, Picman and Schriml 1994). In addition to predation on eggs and nestlings, Blue Jays occasionally prey on fledgling and adult birds (Johnson and Johnson 1976, Dubowy 1985). A majority of reports involve predation on House Sparrows (Passer domesticus) and other small birds (...

  5. Blue enhanced light sources: opportunities and risks

    Science.gov (United States)

    Lang, Dieter

    2012-03-01

    Natural daylight is characterized by high proportions of blue light. By proof of a third type of photoreceptor in the human eye which is only sensitive in this spectral region and by subsequent studies it has become obvious that these blue proportions are essential for human health and well being. In various studies beneficial effects of indoor lighting with higher blue spectral proportions have been proven. On the other hand with increasing use of light sources having enhanced blue light for indoor illumination questions are arising about potential health risks attributed to blue light. Especially LED are showing distinct emission characteristics in the blue. Recently the French agency for food, environmental and occupational health & safety ANSES have raised the question on health issues related to LED light sources and have claimed to avoid use of LED for lighting in schools. In this paper parameters which are relevant for potential health risks will be shown and their contribution to risk factors will quantitatively be discussed. It will be shown how to differentiate between photometric parameters for assessment of beneficial as well as hazardous effects. Guidelines will be discussed how blue enhanced light sources can be used in applications to optimally support human health and well being and simultaneously avoid any risks attributed to blue light by a proper design of lighting parameters. In the conclusion it will be shown that no inherent health risks are related to LED lighting with a proper lighting design.

  6. Quantum dots and spin qubits in graphene

    Energy Technology Data Exchange (ETDEWEB)

    Recher, Patrik; Trauzettel, Bjoern, E-mail: precher@physik.uni-wuerzburg.de, E-mail: trauzettel@physik.uni-wuerzburg.de [Institut fuer Theoretische Physik und Astrophysik, University of Wuerzburg, 97074 Wuerzburg (Germany)

    2010-07-30

    This is a review on graphene quantum dots and their use as a host for spin qubits. We discuss the advantages but also the challenges to use graphene quantum dots for spin qubits as compared to the more standard materials like GaAs. We start with an overview of this young and fascinating field and then discuss gate-tunable quantum dots in detail. We calculate the bound states for three different quantum dot architectures where a bulk gap allows for confinement via electrostatic fields: (i) graphene nanoribbons with armchair boundaries, (ii) a disc in single-layer graphene, and (iii) a disc in bilayer graphene. In order for graphene quantum dots to be useful in the context of spin qubits, one needs to find reliable ways to break the valley degeneracy. This is achieved here, either by a specific termination of graphene in (i) or in (ii) and (iii) by a magnetic field, without the need of a specific boundary. We further discuss how to manipulate spin in these quantum dots and explain the mechanism of spin decoherence and relaxation caused by spin-orbit interaction in combination with electron-phonon coupling, and by hyperfine interaction with the nuclear-spin system. (topical review)

  7. Semiconductor Quantum Dots with Photoresponsive Ligands.

    Science.gov (United States)

    Sansalone, Lorenzo; Tang, Sicheng; Zhang, Yang; Thapaliya, Ek Raj; Raymo, Françisco M; Garcia-Amorós, Jaume

    2016-10-01

    Photochromic or photocaged ligands can be anchored to the outer shell of semiconductor quantum dots in order to control the photophysical properties of these inorganic nanocrystals with optical stimulations. One of the two interconvertible states of the photoresponsive ligands can be designed to accept either an electron or energy from the excited quantum dots and quench their luminescence. Under these conditions, the reversible transformations of photochromic ligands or the irreversible cleavage of photocaged counterparts translates into the possibility to switch luminescence with external control. As an alternative to regulating the photophysics of a quantum dot via the photochemistry of its ligands, the photochemistry of the latter can be controlled by relying on the photophysics of the former. The transfer of excitation energy from a quantum dot to a photocaged ligand populates the excited state of the species adsorbed on the nanocrystal to induce a photochemical reaction. This mechanism, in conjunction with the large two-photon absorption cross section of quantum dots, can be exploited to release nitric oxide or to generate singlet oxygen under near-infrared irradiation. Thus, the combination of semiconductor quantum dots and photoresponsive ligands offers the opportunity to assemble nanostructured constructs with specific functions on the basis of electron or energy transfer processes. The photoswitchable luminescence and ability to photoinduce the release of reactive chemicals, associated with the resulting systems, can be particularly valuable in biomedical research and can, ultimately, lead to the realization of imaging probes for diagnostic applications as well as to therapeutic agents for the treatment of cancer.

  8. Coherent transport through interacting quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Hiltscher, Bastian

    2012-10-05

    The present thesis is composed of four different works. All deal with coherent transport through interacting quantum dots, which are tunnel-coupled to external leads. There a two main motivations for the use of quantum dots. First, they are an ideal device to study the influence of strong Coulomb repulsion, and second, their discrete energy levels can easily be tuned by external gate electrodes to create different transport regimes. The expression of coherence includes a very wide range of physical correlations and, therefore, the four works are basically independent of each other. Before motivating and introducing the different works in more detail, we remark that in all works a diagrammatic real-time perturbation theory is used. The fermionic degrees of freedom of the leads are traced out and the elements of the resulting reduced density matrix can be treated explicitly by means of a generalized master equation. How this equation is solved, depends on the details of the problem under consideration. In the first of the four works adiabatic pumping through an Aharonov-Bohm interferometer with a quantum dot embedded in each of the two arms is studied. In adiabatic pumping transport is generated by varying two system parameters periodically in time. We consider the two dot levels to be these two pumping parameters. Since they are located in different arms of the interferometer, pumping is a quantum mechanical effect purely relying on coherent superpositions of the dot states. It is very challenging to identify a quantum pumping mechanism in experiments, because a capacitive coupling of the gate electrodes to the leads may yield an undesired AC bias voltage, which is rectified by a time dependent conductance. Therefore, distinguishing features of these two transport mechanisms are required. We find that the dependence on the magnetic field is the key feature. While the pumped charge is an odd function of the magnetic flux, the rectified current is even, at least in

  9. Influence of GaAsSb structural properties on the optical properties of InAs/GaAsSb quantum dots

    Science.gov (United States)

    Zhang, Zewen; Huang, Yidan; Reece, Peter J.; Bremner, Stephen P.

    2017-10-01

    The optical properties of InAs quantum dots with GaAsSb buffer, capping and cladding layers of different alloy compositions are studied by photoluminescence techniques. Fully strained GaAsSb layers show that the inclusion of a buffer layer gives a blue-shift to quantum dot emission, while for quantum dots capped with GaAsSb a clear red-shift is seen. Power-dependent photoluminescence suggests a transition from type-I to type-II can be achieved by GaAsSb at Sb composition between 11-13%, while the transition for the GaAsSb cladding layer occurs at around 11%. At low Sb composition, good crystal quality and energy barrier are detected by temperature-dependent photoluminescence, while high-level dislocation and defects exist under high antimony content, as evidenced by X-Ray Diffraction and Transmission Electron Microscopy.

  10. One pot synthesis of highly luminescent polyethylene glycol anchored carbon dots functionalized with a nuclear localization signal peptide for cell nucleus imaging

    Science.gov (United States)

    Yang, Lei; Jiang, Weihua; Qiu, Lipeng; Jiang, Xuewei; Zuo, Daiying; Wang, Dongkai; Yang, Li

    2015-03-01

    Strong blue fluorescent polyethylene glycol (PEG) anchored carbon nitride dots (CDs@PEG) with a high quantum yield (QY) of 75.8% have been synthesized by a one step hydrothermal treatment. CDs with a diameter of ca. 6 nm are well dispersed in water and present a graphite-like structure. Photoluminescence (PL) studies reveal that CDs display excitation-dependent behavior and are stable under various test conditions. Based on the as-prepared CDs, we designed novel cell nucleus targeting imaging carbon dots functionalized with a nuclear localization signal (NLS) peptide. The favourable biocompatibilities of CDs and NLS modified CDs (NLS-CDs) are confirmed by in vitro cytotoxicity assays. Importantly, intracellular localization experiments in MCF7 and A549 cells demonstrate that NLS-CDs could be internalized in the nucleus and show blue light, which indicates that CDs may serve as cell nucleus imaging probes.Strong blue fluorescent polyethylene glycol (PEG) anchored carbon nitride dots (CDs@PEG) with a high quantum yield (QY) of 75.8% have been synthesized by a one step hydrothermal treatment. CDs with a diameter of ca. 6 nm are well dispersed in water and present a graphite-like structure. Photoluminescence (PL) studies reveal that CDs display excitation-dependent behavior and are stable under various test conditions. Based on the as-prepared CDs, we designed novel cell nucleus targeting imaging carbon dots functionalized with a nuclear localization signal (NLS) peptide. The favourable biocompatibilities of CDs and NLS modified CDs (NLS-CDs) are confirmed by in vitro cytotoxicity assays. Importantly, intracellular localization experiments in MCF7 and A549 cells demonstrate that NLS-CDs could be internalized in the nucleus and show blue light, which indicates that CDs may serve as cell nucleus imaging probes. Electronic supplementary information (ESI) available: The formulation of PEGylation CD optimization procedure, Table S1 and Fig. S1-S7. See DOI: 10.1039/c5nr01080

  11. One-pot fabrication of high-quality InP/ZnS (core/shell) quantum dots and their application to cellular imaging.

    Science.gov (United States)

    Hussain, Sahid; Won, Nayoun; Nam, Jutaek; Bang, Jiwon; Chung, Hyokyun; Kim, Sungjee

    2009-07-13

    True colors: High-quality InP and InP/ZnS quantum dots (QDs) are obtained by means of a simple one-pot method in the presence of polyethylene glycol (PEG). Rapid and size-controlled reactions lead to highly crystalline and nearly monodisperse QDs at relatively low temperatures. The particles emit from cyan blue to far-red, and are successfully used in cellular imaging (see figure).

  12. Micromagnetic calculations of Co dots: domain configuration, stability, and inter-dot coupling

    Science.gov (United States)

    Yu, Chengtao; Pearson, John; Li, Dongqi

    2002-03-01

    We have carried out micromagnetic simulations with a public code [1] to investigate the stability of single domain vs. vortex states in hexagonal Co dots of 10-900 nm in diameter and 1-40 nm in thickness, as well as the magnetostatic interactions among dots. The ground state of an isolated dot is determined to be single-domain for small dots, i.e., magneto-static coupling within a dot-pair introduces a uniaxial anisotropy with easy axis along the pair direction, which corresponds to 5 Oe at a pair distance of 640 nm, and increases to 270 Oe when two dots connect to each other. The results are compared to the experimental results of our self-assembled Co dots and dot chains [2]. * Work supported by DOE BES-MS under #W-31-109-ENG-38. 1. M.J. Donahue and D.G. Porter, http://math.nist.gov/oommf. 2. Chengtao Yu, Dongqi Li, J. Pearson, and S. Bader, Appl. Phys. Lett. 78, 1228 (2001); ibid. 79 (in press).

  13. Computational intelligence applied to the growth of quantum dots

    Science.gov (United States)

    Singulani, Anderson P.; Vilela Neto, Omar P.; Aurélio Pacheco, Marco C.; Vellasco, Marley B. R.; Pires, Maurício P.; Souza, Patrícia L.

    2008-11-01

    We apply two computational intelligence techniques, namely, artificial neural network and genetic algorithm to the growth of self-assembled quantum dots. The method relies on an existing database of growth parameters with a resulting quantum dot characteristic to be able to later obtain the growth parameters needed to reach a specific value for such a quantum dot characteristic. The computational techniques were used to associate the growth input parameters with the mean height of the deposited quantum dots. Trends of the quantum dot mean height behavior as a function of growth parameters were correctly predicted and the growth parameters required to minimize the quantum dot mean height were provided.

  14. Ionophore-based optical nanosensors incorporating hydrophobic carbon dots and a pH-sensitive quencher dye for sodium detection.

    Science.gov (United States)

    Galyean, A A; Behr, M R; Cash, K J

    2018-01-21

    Nanosensors present a biological monitoring method that is biocompatible, reversible, and nano-scale, and they offer many advantages over traditional organic indicators. Typical ionophore-based nanosensors incorporate nile-blue derivative pH indicators but suffer from photobleaching while quantum dot alternatives pose a potential toxicity risk. In order to address this challenge, sodium selective nanosensors containing carbon dots and a pH-sensitive quencher molecule were developed based on an ion-exchange theory and a decoupled recognition element from the pH indicator. Carbon dots were synthesized and integrated into nanosensors containing a pH-indicator, an analyte-binding ligand (ionophore), and a charge-balancing additive. These nanosensors are ion-selective against potassium (selectivity coefficient of 0.4) and lithium (selectivity coefficient of 0.9). Reversible nanosensor response to sodium is also demonstrated. The carbon dot nanosensors are resistant to changes in optical properties for at least 12 h and display stable selectivity to physiologically-relevant sodium (alpha = 0.5 of 200 mM NaCl) for a minimum of 6 days.

  15. Los trastornos severos del desarrollo y el proceso de constitución psíquica Severe developmental disorders and the process of psychic constitution

    Directory of Open Access Journals (Sweden)

    Juan José Calzetta

    2011-12-01

    Full Text Available Este proyecto tiene, como uno de sus objetivos, estudiar las peculiaridades en la estructuración del aparato psíquico a partir del proceso de adquisición de escritura, bajo condiciones particulares, en niños y jóvenes que carecen de lenguaje oral o poseen un lenguaje oral muy limitado, ecolálico o bizarro, inadecuado para la comunicación, y no utilizan señas ni escritura manuscrita espontánea. Se presenta, a modo de ejemplo, una síntesis de los avances en la escritura y modificaciones de las manifestaciones de estructuración psíquica producto de la misma, en un adolescente de 16 años que carecía prácticamente de lenguaje oral al comenzar el tratamiento siete años atrás. Se discute la validez de los modelos teóricos utilizados en relación con los casos abordados así como el aporte que se puede realizar al conocimiento del proceso general de constitución, los principios reguladores y la forma de funcionamiento inicial del aparato psíquico dado que en estos casos las condiciones de producción del mismo divergen considerablemente de las habituales.One of the objectives of this research is to explore the peculiarities in the structuring of the psychic apparatus, by means of the process of writing acquisition under specific conditions, in children and young people lacking or presenting a very limited oral language, echolalic or bizarre, inappropriate for communication, and do not use either signs or spontaneous handwriting. We show as an example, a summary of the progress in writing and its subsequent modification of the manifestations of psychic structuring, in an adolescent of sixteen years old lacking the oral language at the beginning of the treatment seven years ago. We discuss the validity of the theoretical models used as well as the possible contribution to understand the overall process of constitution, the regulatory principles, and the initial functioning of the psychic apparatus.

  16. Type I-type II transition of self-assembled In{sub 0.55}Al{sub 0.45}As/Al{sub 0.5}Ga{sub 0.5}As quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Li, G.H.; Chen, Y.; Fung, Z.L.; Ding, K.; Han, H.X. [Academia Sinica, Beijing, BJ (China). Inst. of Semiconductors; Zhou, W.; Wang, Z.G. [Chinese Academy of Sciences, Beijing, BJ (China). Lab. of Semiconductor for Materials Science

    2001-01-01

    The photoluminescence (PL) of In{sub 0.55}Al{sub 0.45}As/Al{sub 0.5}Ga{sub 0.5}As self-assembled quantum dots has been measured at 15 and 80 K under hydrostatic pressure. The lateral size of the dots ranges from 7 to 62 nm. The emissions from the dots with 26, 52 and 62 nm size have a blue shift under pressure, indicating that these quantum dots have the normal type-I structure with lowest conduction band at the {gamma}-valley. However, the PL peak of dots with 7 nm diameter moves to lower energy with increasing pressure. It is a typical character for the X-related transition. Then these small dots have a type-II structure with the X-valley as the lowest conduction level. An envelope-function calculation confirms that the {gamma}-like exciton transition energy will rise above the X-like transition energy in the In{sub 0.55}Al{sub 0.45}As/Al{sub 0.5}Ga{sub 0.5}As structure if the dot size is small enough. (orig.)

  17. Emission properties of colloidal quantum dots on polyelectrolyte multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Komarala, Vamsi K [Semiconductor Photonics Group, School of Physics, Trinity College Dublin (Ireland); Rakovich, Yury P [Semiconductor Photonics Group, School of Physics, Trinity College Dublin (Ireland); Bradley, A Louise [Semiconductor Photonics Group, School of Physics, Trinity College Dublin (Ireland); Byrne, Stephen J [School of Chemistry, Trinity College Dublin, Republic of (Ireland); Corr, Serena A [School of Chemistry, Trinity College Dublin, Republic of (Ireland); Gun' ko, Yurii K [School of Chemistry, Trinity College Dublin (Ireland)

    2006-08-28

    We present steady state and time-resolved photoluminescence (PL) characteristics of differently charged CdTe quantum dots (QDs) adsorbed onto a polyelectrolyte (PE) multilayer. The PE multilayer is built up using a layer-by-layer assembly technique. We find that the diffusion of the QDs into the PE multilayer is an important factor in the case of 3-mercapto-1, 2-propanediol stabilized QDs (neutral surface charge), resulting in a {approx}31-fold enhancement in PL intensity accompanied by a blue shift in the PL spectra and an increase in decay lifetime from 3.74 ns to a maximum of 11.65 ns. These modified emission properties are attributed to the enhanced surface related emission resulting from the interaction of the QD's surface with the PE. We find that diffusion does not occur for thioglycolic acid (TGA) stabilized QDs (negative surface charge) or 2-mercaptoethylamine stabilized QDs (positive surface charge), indicating localization of the QDs on top of the PE multilayer. However, the PL lifetime of the TGA stabilized QDs decreases from 9.58 to 5.78 ns with increasing PE multilayer thickness. This provides evidence for increased intrinsic exciton recombination relative to surface related emission, which results in an overall reduction in the average lifetime. Our studies indicate the importance of the QD surface charge in determining the interaction with the PE multilayers and the subsequent modification of the QD emission properties.

  18. Optofluidic FRET lasers using aqueous quantum dots as donors.

    Science.gov (United States)

    Chen, Qiushu; Kiraz, Alper; Fan, Xudong

    2016-01-21

    An optofluidic FRET (fluorescence resonance energy transfer) laser is formed by putting FRET pairs inside a microcavity acting as a gain medium. This integration of an optofluidic laser and the FRET mechanism provides novel research frontiers, including sensitive biochemical analysis and novel photonic devices, such as on-chip coherent light sources and bio-tunable lasers. Here, we investigated an optofluidic FRET laser using quantum dots (QDs) as FRET donors. We achieved lasing from Cy5 as the acceptor in a QD-Cy5 pair upon excitation at 450 nm, where Cy5 has negligible absorption by itself. The threshold was approximately 14 μJ mm(-2). The demonstrated capability of QDs as donors in the FRET laser greatly improves the versatility of optofluidic laser operation due to the broad and large absorption cross section of the QDs in the blue and UV spectral regions. The excitation efficiency of the acceptor molecules through a FRET channel was also analyzed, showing that the energy transfer rate and the non-radiative Auger recombination rate of QDs play a significant role in FRET laser performance.

  19. Gel-like Carbon Dots: Characterization and their Potential Applications.

    Science.gov (United States)

    Zhou, Yiqun; Desserre, Alexandra; Sharma, Shiv K; Li, Shanghao; Marksberry, M Hensley; Chusuei, Charles C; Blackwelder, Patricia L; Leblanc, Roger M

    2017-04-19

    Highly photoluminescent gel-like carbon dots (G-CDs) were successfully synthesized for the first time by a rapid one-step solvothermal synthesis approach with citric acid and 1,2-ethylenediamine as the precursors. Their gel-like nature was revealed by the Tyndall and coagulation effects, which were elucidated by a negative ζ potential value. The influences of temperature on the properties and sizes of these G-CDs were analyzed, and the best method for a maximum quantum yield was identified. The resulting products emitted blue photoluminescence under UV light (λ=365 nm) and a gradient of color under regular light. In addition, the UV/Vis absorption and fluorescence emission spectra of the G-CDs indicated that those synthesized at 160 °C exhibited the highest fluorescence quantum yield (33 %). Atomic force microscopy and transmission electron microscopy measurements were performed, and a higher temperature of formation resulted in smaller G-CDs. Furthermore, band shifts in the UV/Vis and fluorescence spectra and sequential changes in the quantum yield values and ζ potentials in addition to elemental compositional changes as determined by X-ray photoelectron spectroscopy were monitored throughout the formation process of the G-CDs. As to applications, G-CDs were prepared as an invisible ink for printers, which exhibited the applicability of G-CDs in daily life and military activities. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. High quality factor photonic resonators for nitride quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Guillet, T. [Universite Montpellier 2, Laboratoire Charles Coulomb UMR 5221, 34095 Montpellier (France); Mexis, M.; Rennesson, S.; Brimont, C.; Bretagnon, T.; Gil, B. [Universite Montpellier 2, Laboratoire Charles Coulomb UMR 5221, 34095 Montpellier (France); CNRS, Laboratoire Charles Coulomb UMR 5221, 34095 Montpellier (France); Sergent, S. [CRHEA-CNRS, Valbonne 06560 (France); Universite de Nice Sophia Antipolis, Parc Valrose, Nice 06102 Cedex 2 (France); Neel, D.; David, S.; Checoury, X.; Boucaud, P. [Institut d' Electronique Fondamentale, CNRS - Universite Paris Sud 11, 91405 Orsay (France); Sam-Giao, D.; Gayral, B. [CEA-INAC, 17 rue des Martyrs, 38054 Grenoble (France); Semond, F.; Leroux, M. [CRHEA-CNRS, Valbonne 06560 (France)

    2012-03-15

    We report the realization and the optical study of nitride photonic resonators dedicated to the blue and UV spectral range. Microdisks and photonic crystal (PC) cavities are investigated containing GaN/AlN quantum dots (QDs) embedded in an AlN waveguide. The PC cavities are fabricated through the conformal growth of nitrides on a patterned Si substrate, and present delocalized and confined cavity modes in their microphotoluminescence spectra, that are compared to simulations. A large quality factor of 1800 is reached for a modified L3 cavity. In the case of microdisks, which are fabricated through a classical top-down approach, the series of whispering gallery modes (WGMs) with large quality factors (up to 7300) are observed and analysed. Scanning electron micrograph and microphotoluminescence spectrum of a 2 {mu}m AlN microdisk embedding GaN QDs; the WGMs appear as sharp peaks, with quality factors up to 5000. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Highly Photoluminescent and Stable Aqueous ZnS Quantum Dots

    Science.gov (United States)

    Li, Hui; Shih, Wan Y.; Shih, Wei-Heng

    2009-01-01

    We report an all-aqueous synthesis of highly photoluminescent and stable ZnS quantum dots (QDs) with water as the medium, i.e. first synthesizing ZnS QDs with 3-mercaptopropionic acid (MPA) as the capping molecule, followed by replacing some of MPA with (3-mercaptopropyl) trimethoxysilane (MPS). The resultant MPS-replaced ZnS QDs were about 5 nm in size with a cubic zinc blende crystalline structure, and had both MPA and MPS on the surface as confirmed by the Fourier Transform Infrared (FTIR) spectroscopy. They exhibited blue trap-state emissions around 415 nm and a quantum yield (QY) of 75% with Rhodamine 101 as the reference, and remained stable for more than 60 days under the ambient conditions. Through the capping molecule replacement procedure, the MPS-replaced ZnS QDs avoided the shortcomings of both the MPA-ZnS QDs and the MPS-ZnS QDs, and acquired the advantages of strong photoluminescence and good stability, which are important to the QDs’ applications especially for bioimaging. PMID:21954321

  2. Binding Quantum Dots to Silk Biomaterials for Optical Sensing

    Directory of Open Access Journals (Sweden)

    Disi Lu

    2015-01-01

    Full Text Available Quantum dots (QDs, have great potential for fabricating optical sensing devices and imaging biomaterial degradation in vivo. In the present study, 2-mercaptoethylamine- (MEA- and mercaptopropionic acid- (MPA- capped CdTe-QDs were physically incorporated in silk films that contained a high content (>30% of crystalline beta-sheet structure. The beta-sheets were induced by the addition of glycerol, water annealing, glycerol/annealing, or treatment with methanol. Incorporation of QDs did not influence the formation of beta-sheets. When the films were extracted with water, most QDs remained associated with the silk, based on the retention of photoluminescence in the silk films and negligible photoluminescence in the extracts. Compared to the solution state, photoluminescence intensity significantly decreased for MEA-QDs but not for MPA-QDs in the silk films, while the emission maximum blue shifted (≈4 nm slightly for both. Further film digestion using protease XIV, alpha-chymotrypsin, and the combination of the two proteases suggested that QDs may be bound to the silk beta-sheet regions but not the amorphous regions. QDs photoluminescence in silk films was quenched when the concentration of hydrogen peroxide (H2O2 was above 0.2-0.3 mM, indicating the QDs-incorporated silk films can be used to report oxidation potential in solution.

  3. Tuning the Emission Energy of Chemically Doped Graphene Quantum Dots

    Directory of Open Access Journals (Sweden)

    Noor-Ul-Ain

    2016-11-01

    Full Text Available Tuning the emission energy of graphene quantum dots (GQDs and understanding the reason of tunability is essential for the GOD function in optoelectronic devices. Besides material-based challenges, the way to realize chemical doping and band gap tuning also pose a serious challenge. In this study, we tuned the emission energy of GQDs by substitutional doping using chlorine, nitrogen, boron, sodium, and potassium dopants in solution form. Photoluminescence data obtained from (Cl- and N-doped GQDs and (B-, Na-, and K-doped GQDs, respectively exhibited red- and blue-shift with respect to the photoluminescence of the undoped GQDs. X-ray photoemission spectroscopy (XPS revealed that oxygen functional groups were attached to GQDs. We qualitatively correlate red-shift of the photoluminescence with the oxygen functional groups using literature references which demonstrates that more oxygen containing groups leads to the formation of more defect states and is the reason of observed red-shift of luminescence in GQDs. Further on, time resolved photoluminescence measurements of Cl- and N-GQDs demonstrated that Cl substitution in GQDs has effective role in radiative transition whereas in N-GQDs leads to photoluminescence (PL quenching with non-radiative transition to ground state. Presumably oxidation or reduction processes cause a change of effective size and the bandgap.

  4. Tuning the Emission Energy of Chemically Doped Graphene Quantum Dots.

    Science.gov (United States)

    Noor-Ul-Ain; Eriksson, Martin O; Schmidt, Susann; Asghar, M; Lin, Pin-Cheng; Holtz, Per Olof; Syväjärvi, Mikael; Yazdi, G Reza

    2016-11-03

    Tuning the emission energy of graphene quantum dots (GQDs) and understanding the reason of tunability is essential for the GOD function in optoelectronic devices. Besides material-based challenges, the way to realize chemical doping and band gap tuning also pose a serious challenge. In this study, we tuned the emission energy of GQDs by substitutional doping using chlorine, nitrogen, boron, sodium, and potassium dopants in solution form. Photoluminescence data obtained from (Cl- and N-doped) GQDs and (B-, Na-, and K-doped) GQDs, respectively exhibited red- and blue-shift with respect to the photoluminescence of the undoped GQDs. X-ray photoemission spectroscopy (XPS) revealed that oxygen functional groups were attached to GQDs. We qualitatively correlate red-shift of the photoluminescence with the oxygen functional groups using literature references which demonstrates that more oxygen containing groups leads to the formation of more defect states and is the reason of observed red-shift of luminescence in GQDs. Further on, time resolved photoluminescence measurements of Cl- and N-GQDs demonstrated that Cl substitution in GQDs has effective role in radiative transition whereas in N-GQDs leads to photoluminescence (PL) quenching with non-radiative transition to ground state. Presumably oxidation or reduction processes cause a change of effective size and the bandgap.

  5. Tapered photonic crystal fibers for blue-enhanced supercontinuum generation

    DEFF Research Database (Denmark)

    Møller, Uffe; Sørensen, Simon Toft; Larsen, Casper

    2012-01-01

    Tapering of photonic crystal fibers is an effective way of shifting the blue edge of a supercontinuum spectrum down in the deep-blue. We discuss the optimum taper profile for enhancing the power in the blue edge.......Tapering of photonic crystal fibers is an effective way of shifting the blue edge of a supercontinuum spectrum down in the deep-blue. We discuss the optimum taper profile for enhancing the power in the blue edge....

  6. Submonolayer Quantum Dot Infrared Photodetector

    Science.gov (United States)

    Ting, David Z.; Bandara, Sumith V.; Gunapala, Sarath D.; Chang, Yia-Chang

    2010-01-01

    A method has been developed for inserting submonolayer (SML) quantum dots (QDs) or SML QD stacks, instead of conventional Stranski-Krastanov (S-K) QDs, into the active region of intersubband photodetectors. A typical configuration would be InAs SML QDs embedded in thin layers of GaAs, surrounded by AlGaAs barriers. Here, the GaAs and the AlGaAs have nearly the same lattice constant, while InAs has a larger lattice constant. In QD infrared photodetector, the important quantization directions are in the plane perpendicular to the normal incidence radiation. In-plane quantization is what enables the absorption of normal incidence radiation. The height of the S-K QD controls the positions of the quantized energy levels, but is not critically important to the desired normal incidence absorption properties. The SML QD or SML QD stack configurations give more control of the structure grown, retains normal incidence absorption properties, and decreases the strain build-up to allow thicker active layers for higher quantum efficiency.

  7. Biphasic quantum dots of cubic and hexagonal Mn doped CdS; necessity of Rietveld analysis

    Energy Technology Data Exchange (ETDEWEB)

    Heiba, Zein K., E-mail: zein_kh@yahoo.com [Ain Shams University, Faculty of Science, Physics Department, Cairo (Egypt); Taif University, Faculty of Science, Physics Department (Saudi Arabia); Mohamed, Mohamed Bakr [Ain Shams University, Faculty of Science, Physics Department, Cairo (Egypt); Imam, N.G. [Experimental Physics Department, Nuclear Research Center, Atomic Energy Authority, 13759 Cairo (Egypt)

    2015-01-05

    Highlights: • Mn{sup 2+} doped CdS quantum dots (QDs) were prepared via a simple chemical synthesis procedure. • Biphasic composite of CdS QDs was revealed with maximum magnetism at 10 at.% of Mn{sup 2+}. • Rietveld structural analysis is a necessity for dealing with nano or quantum dots chalcogenides. • Full investigation of effects of Mn doping on the structural, optical and magnetic parameters. - Abstract: Mn{sup 2+} doped CdS quantum dots (QDs) were prepared via a simple chemical synthesis method. Incorporation of Mn ions into CdS QDs was monitored by structural, magnetic and optical spectroscopy analysis. Although the diffraction patterns seemed to be single wurtzite hexagonal structure, analysis revealed biphasic composite of CdS QDs hexagonal wurtzite and cubic zinc blende. The band gap, crystal phase and the morphology of CdS QDs were found not to be greatly affected by Mn{sup 2+} doping, however there was an optimal Mn{sup 2+} doping content of 10% where the magnetism is maximum. The recorded photoluminescence (PL) emission spectra, excited at 370 nm, depict emission lines in the UV and blue-shift regions. The emission band reveals that the band gap of pure CdS QDs is around 3 eV which is greater than that of bulk CdS (2.42 eV). The band gap of Mn:CdS QDs is almost independent of Mn content (x) and the crystallite size remains almost the same for all values of x. The observed structural, magnetic and optical properties have been explained on the basis of formation of two phases of CdS doped with Mn. This work aims to highlight recent advances in the synthesis of Mn:CdS diluted magnetic semiconductor quantum dots and their wonderful performance.

  8. Luminescent InP Quantum Dots with Tunable Emission by Post-Synthetic Modification with Lewis Acids.

    Science.gov (United States)

    Stein, Jennifer L; Mader, Elizabeth A; Cossairt, Brandi M

    2016-04-07

    We demonstrate the ability of M(2+) Lewis acids (M = Cd, Zn) to dramatically enhance the photoluminescence quantum yield (PL QY) of InP quantum dots. The addition of cadmium and zinc is additionally found to red- and blue-shift, respectively, the lowest energy absorption and emission of InP quantum dots while maintaining particle size. This treatment results in a facile strategy to post-synthetically tune the luminescence color in these materials. Optical and structural characterization (XRD, TEM, XAS, ICP) have led us to identify the primary mechanism of PL turn-on as surface passivation of phosphorus dangling bonds, affording PL QYs up to 49% without the growth of a type I shell or the addition of HF. This route to PL enhancement and color tuning may prove useful as a standalone treatment or as a complement to shelling strategies.

  9. RETRACTED ARTICLE: Cu2ZnSnSe4 quantum dots with controllable size and quantum confinement effect

    Science.gov (United States)

    Zong, Kai; Lu, SiHeng; Wang, Hao; Sun, YuXiu; Liu, JingBing; Yan, Hui

    2013-09-01

    Cu2ZnSnSe4 quantum dots (QDs) with controllable sizes have been synthesized via a hot-injection method. The diameters of the QDs range from 3.2 to 10.1 nm with the tunable band gap from 1.27 to 1.54 eV by adjusting the reaction temperatures from 180 to 240 °C. Structural and Raman scattering data confirm that Cu2ZnSnSe4 is obtained without other secondary phases. The band gaps of the QDs with diameters less than 4.6 nm show an obvious blue shift to higher energy due to quantum confinement effect. It indicates that the Cu2ZnSnSe4 QDs can be a potential candidate for quantum-dot-sensitized solar cells in the future.

  10. Rapid, easy and economical dot EIA for detection of antibodies to HIV-1 using recombinant env- and gag-proteins.

    Science.gov (United States)

    Müller, R; Glathe, H; Lang, H; Simon, H; Clausnitzer, R; Petzold, G; Dittmann, S

    1991-01-01

    A rapid and simple screening test for antibodies to HIV-1 was designed on the principle of dot-EIA. Recombinant HIV-1 env and gag polypeptides are fixed on nitrocellulose sheets. Peroxidase conjugated protein A is used for detection of bound antibodies. After addition of hydrogen peroxide and 2-bromo-1-naphtol antigen-antibody complexes are visualized as discrete blue coloured spots. The test is completed within 15 min. Out of 111 sera positive by commercial EIA and Western blot analysis 110 were recognized by dot-EIA (sensitivity: 99.1%). False positive results compared with commercial EIA were found in 2 of 423 healthy blood donors (specificity: 99.5%).

  11. Can greening of aquaculture sequester blue carbon?

    Science.gov (United States)

    Ahmed, Nesar; Bunting, Stuart W; Glaser, Marion; Flaherty, Mark S; Diana, James S

    2017-05-01

    Globally, blue carbon (i.e., carbon in coastal and marine ecosystems) emissions have been seriously augmented due to the devastating effects of anthropogenic pressures on coastal ecosystems including mangrove swamps, salt marshes, and seagrass meadows. The greening of aquaculture, however, including an ecosystem approach to Integrated Aquaculture-Agriculture (IAA) and Integrated Multi-Trophic Aquaculture (IMTA) could play a significant role in reversing this trend, enhancing coastal ecosystems, and sequestering blue carbon. Ponds within IAA farming systems sequester more carbon per unit area than conventional fish ponds, natural lakes, and inland seas. The translocation of shrimp culture from mangrove swamps to offshore IMTA could reduce mangrove loss, reverse blue carbon emissions, and in turn increase storage of blue carbon through restoration of mangroves. Moreover, offshore IMTA may create a barrier to trawl fishing which in turn could help restore seagrasses and further enhance blue carbon sequestration. Seaweed and shellfish culture within IMTA could also help to sequester more blue carbon. The greening of aquaculture could face several challenges that need to be addressed in order to realize substantial benefits from enhanced blue carbon sequestration and eventually contribute to global climate change mitigation.

  12. Skin discoloration with blue food coloring.

    Science.gov (United States)

    Zillich, A J; Kuhn, R J; Petersen, T J

    2000-01-01

    To describe a pediatric patient who developed a clinical cyanotic appearance after receiving an excessive amount of blue food coloring. An 11-year-old white girl with cerebral palsy was admitted for unresolving aspiration pneumonia and dehydration. Antibiotics and intravenous fluids were administered. During the hospital course, enteral nutrition containing blue food coloring was also administered. Twelve hours after the start of enteral nutrition, the patient appeared cyanotic despite a regular respiratory rate and normal oxygen saturation. The pediatric code response team was called. Enteral nutrition was stopped and then restarted without blue food coloring. Over the next 24 hours, the cyanotic appearance resolved and no further complications developed. At our institution, blue food coloring is used with enteral nutrition for detecting aspiration of stomach contents. The dietary department supplies food coloring to each nursing unit in pint-sized medicine bottles. Nurses place an unstandardized amount of blue food coloring into each enteral nutrition bag. This child received an unspecified amount of FD&C Blue No. 1 food coloring. No toxicity studies exist for acute or human ingestion, but the National Academy of Sciences lists 363 mg/d of FD&C Blue No. 1 as a safe level for humans. We estimated this child ingested 780-3,940 mg of dye over a 12-hour period. This is the first known report of an adverse effect from blue food coloring. To prevent similar occurrences within our institution, the blue food coloring for tube feedings will be dispensed by the pharmacy department in standardized units.

  13. Brilliant blue in vitreoretinal surgery.

    Science.gov (United States)

    Enaida, Hiroshi; Ishibashi, Tatsuro

    2008-01-01

    This paper reviews the preclinical effects of brilliant blue G (BBG) on the morphology and functions of the retina, and reports on a pilot study of BBG staining and subsequent peeling of the internal limiting membrane (ILM) during vitreoretinal surgery. BBG solution was injected into rat eyes and investigated using light microscopy and electron microscopy, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining, and electroretinography (ERG). No pathological changes were caused by the BBG intravitreous injection. Although electron microscopy revealed that high doses of BBG induced vacuolization in the inner retinal cells, there was no reduction in the amplitude of the ERG waves and no detectable toxic effects. In the primate eyes, the ILM was clearly visualized by BBG staining, and peeled off easily from the retina. In the clinical study, BBG improved visualization of the ILM, allowing peeling and surgery to be performed successfully on patients with various vitroretinal diseases. Improvement of postoperative visual acuity was obtained in most cases, and no adverse effects were observed postoperatively. In conclusion, BBG has low toxicity, high staining ability, and is easy to handle, making it a good candidate dye for visualizing vitreoretinal disease surgery without adverse effects.

  14. Photoluminescent (PL) or electroluminescent (EL) quantum dots for display, lighting, and photomedicine (Conference Presentation)

    Science.gov (United States)

    Dong, Yajie

    2017-02-01

    Quantum dots (QDs) have gone through a long journey before finding their ways into the display field. This talk will briefly touch on the history before trying to answer several key questions related to QDs applications in display: What are QDs? How are they made? What properties do they have and Why? How can these properties be used to improve color and efficiency of display, in either photoluminescence (PL) or electroluminescence (EL) mode? And what are the remaining challenges for QDs wide adoption in display industry? Lastly, some most recent progresses in our UCF lab at both PL and EL fronts will be highlighted. For PL, a cadmium-free perovskite-polymer composite films with exceptionally narrow emission green peaks (FWHM 20 nm) and good water and thermal stability will be reported. Together with red quantum dots or PFS/KSF phosphors as down-converters for blue LEDs, a white-light source with 95% Rec. 2020 color gamut was demonstrated [1]. For EL, red quantum dot light emitting devices (QLEDs) with record luminance of 165,000 Cd/m2 has been obtained at a current density of 1000 mA/cm2 with a low driving voltage of 5.8 V and CIE coordinates of (0.69, 0.31). [2] The potential of using these QLEDs for light sources for integrated sensing platform [3] or high efficiency, high color quality hybrid white OLED [4] will be discussed. [1] Y. N. Wang, J. He, H. Chen, J. S. Chen, R. D. Zhu, P. Ma, A. Towers, Y. Lin, A. J. Gesquiere, S. T. Wu, Y. J. Dong. Ultrastable, Highly Luminescent Organic-Inorganic Perovskite - Polymer Composite Films, Advanced Materials, accepted, (2016). [2] Y. J. Dong, J.M. Caruge, Z. Q. Zhou, C. Hamilton, Z. Popovic, J. Ho, M. Stevenson, G. Liu, V. Bulovic, M. Bawendi, P. T. Kazlas, S. Coe-Sullivan, and J. Steckel Ultra-bright, Highly Efficient, Low Roll-off Inverted Quantum-Dot Light Emitting Devices (QLEDs). SID Symp. Dig. Tech. Pap. 46, 270-273 (2015). [3] J. He, H. Chen, S. T. Wu, and Y. J. Dong, Integrated Sensing Platform Based on Quantum

  15. AlInAs quantum dots

    Science.gov (United States)

    Gaisler, A. V.; Derebezov, I. A.; Gaisler, V. A.; Dmitriev, D. V.; Toropov, A. I.; Kozhukhov, A. S.; Shcheglov, D. V.; Latyshev, A. V.; Aseev, A. L.

    2017-01-01

    A system of quantum dots on the basis of AlxIn1-xAs/AlyGa1-y As solid solutions has been studied. The usage of broadband AlxIn1-x solid solutions as the basis of quantum dots makes it possible to expand considerably the spectral emission range into the short-wave region, including the wavelength region near 770 nm being of interest for the design of aerospace systems of quantum cryptography. The optical characteristics of single AlxIn1-xAs quantum dots grown according to the Stranski-Krastanov mechanism are studied by the cryogenic microphotoluminescence method. The fine structure of exciton states of quantum dots is studied in the wavelength region near 770 nm. It is shown that the splitting of exciton states is comparable with the natural width of exciton lines, which is of great interest for the design of emitters of pairs of entangled photons on the basis of AlxAs1-x quantum dots.

  16. Electrostatically confined trilayer graphene quantum dots

    Science.gov (United States)

    Mirzakhani, M.; Zarenia, M.; Vasilopoulos, P.; Peeters, F. M.

    2017-04-01

    Electrically gating of trilayer graphene (TLG) opens a band gap offering the possibility to electrically engineer TLG quantum dots. We study the energy levels of such quantum dots and investigate their dependence on a perpendicular magnetic field B and different types of stacking of the graphene layers. The dots are modeled as circular and confined by a truncated parabolic potential which can be realized by nanostructured gates or position-dependent doping. The energy spectra exhibit the intervalley symmetry EKe(m ) =-EK'h(m ) for the electron (e ) and hole (h ) states, where m is the angular momentum quantum number and K and K ' label the two valleys. The electron and hole spectra for B =0 are twofold degenerate due to the intervalley symmetry EK(m ) =EK'[-(m +1 ) ] . For both ABC [α =1.5 (1.2) for large (small) R ] and ABA (α =1 ) stackings, the lowest-energy levels show approximately a R-α dependence on the dot radius R in contrast with the 1 /R3 one for ABC-stacked dots with infinite-mass boundary. As functions of the field B , the oscillator strengths for dipole-allowed transitions differ drastically for the two types of stackings.

  17. Thermoelectric properties of hexagonal graphene quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Yonghong, E-mail: yhyan@fudan.edu.cn [Department of Physics, Shaoxing University, Shaoxing 312000 (China); Liang, Qi-Feng [Department of Physics, Shaoxing University, Shaoxing 312000 (China); Zhao, Hui [Department of Physics, Tongji University, Shanghai 200092 (China); Wu, Chang-Qin [Department of Physics, Fudan University, Shanghai 200433 (China)

    2012-02-27

    By using the atomistic nonequilibrium Green's function method, we investigate the thermoelectric properties of graphene nanoribbons in the presence of two constrictions (or hexagonal graphene quantum dots). With decreasing widths of the constrictions, the thermal conductance of the nanoribbon can be reduced largely while S{sup 2}G{sub e} (S is the Seebeck coefficient and G{sub e} is the electronic conductance) remains still high as compared with the results of the pristine nanoribbon. Thus, the thermoelectric figure of merit ZT can be enhanced largely. In fact, in the presence of narrowest constrictions the ZT values of the zigzag quantum dots can exceed one at room temperature, while the ZT values of the armchair quantum dots may be close to one, depending on the size of the dot. -- Highlights: ► We study thermoelectric properties of hexagonal graphene quantum dots. ► By point contacts to two leads, the thermal conductance can be reduced greatly while keeping the power factor still high. ► Thermoelectric figure of merit (ZT) can exceed unity.

  18. Función del síntoma en la estructura psíquica. // Role of the sympthom in the psychic structure.

    Directory of Open Access Journals (Sweden)

    Marcela Ana Negro.

    2009-06-01

    Full Text Available This work intends to make a brief survey about the role played by the symptom, according to Freud, in the psychic structure, and then to place what he sets out about it at the end of the cure. Freud gives several definitions of symptom but, for this research’s aim, only one of them will be taken: that given in the "Project", where he states it is a mnemic symbol. The hypothesis of the work is as follows: if this definition doesn’t allow the idea of a symptom with a supporting role in the constitution of the psychic structure to slip in. From this point, the question about Freud's route for an analysis comes up. The way in is through the symptom. But ¿what about it at the end? // Este trabajo se propone hacer un breve desarrollo sobre el lugar que ocupa, para Freud, el síntoma en la estructura psíquica, para luego situar qué es lo que plantea de él en el final de la cura. Freud da varias definiciones del síntoma, pero, para el fin de esta investigación, se tomará una sola de ellas —la que da en el “Proyecto”—, donde dice que el síntoma es un símbolo mnémico. La hipótesis del trabajo es la siguiente: si esta definición no deja deslizar la idea de una función soporte del síntoma en la constitución de la estructura psíquica. Partiendo de este punto, surge la pregunta por el recorrido de un análisis para Freud. La entrada es por el síntoma. Pero, ¿qué hay de él al final?

  19. Quantum dot-assembled nanoparticles with polydiacetylene supramolecule toward label-free, multiplexed optical detection.

    Science.gov (United States)

    Kyeong, San; Kang, Homan; Yim, Joonhyuk; Jeon, Su-Ji; Jeong, Cheol Hwan; Lee, Yoon-Sik; Jun, Bong-Hyun; Kim, Jong-Ho

    2013-03-15

    Quantum dot (QD)-assembled silica nanoparticles bearing a polydiacetylene (PDA) supramolecule on their surface (SiO(2)@QDs@PDA NPs) were developed for label-free and multiplexed detection of biological molecules. Two types of QD-assembled silica NPs (SiO(2)@QDs NPs) were prepared and coated with the PDA supramolecule via photo-induced polymerization of 10,12-pentacosadiynoic acid. One of the SiO(2)@QDs NPs was embedded with blue-QDs, and the other was embedded with green-QDs for encoding. The resulting SiO(2)@QDs@PDA NPs showed discrete QD photoluminescence for encoding as well as PDA fluorescence for sensing a target without interference or overlap. Under heating stress of the SiO(2)@QDs@PDA NPs, the color of the PDA changed from blue to red, which allowed us to observe the fluorescence emitted from red PDA. The mixture of two different SiO(2)@QDs@PDA NPs, SiO(2)@QDs@blue-PDA NPs not emitting the fluorescence of PDA and SiO(2)@QDs@red-PDA NPs where stress was brought onto turn on the PDA fluorescence, was effectively imaged and readily distinguished via fluorescence microscopy, indicating their potential for label-free and multiplexed detection of target molecules. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Analysis of MoDOT communication and outreach effectiveness

    Science.gov (United States)

    2008-07-01

    Personal interviews were held with MoDOT personnel to assess MoDOTs current communication practices and existing customer segmentation practices. Focus groups were then held to help gauge the effectiveness of existing communication practices and t...

  1. Inorganic passivation and doping control in colloidal quantum dot photovoltaics

    KAUST Repository

    Hoogland, Sjoerd H.

    2012-01-01

    We discuss strategies to reduce midgap trap state densities in colloidal quantum dot films and requirements to control doping type and magnitude. We demonstrate that these improvements result in colloidal quantum dot solar cells with certified 7.0% efficiency.

  2. TxDOT administration research : tasks completed in FY2009.

    Science.gov (United States)

    2010-01-01

    Texas Department of Transportation (TxDOT) Project 0-6581-TI, TxDOT Administration : Research, encompasses multiple tasks that explore and support administrative aspects of : transportation research. : The project term began in October 2008 and has b...

  3. Surface treatment of nanocrystal quantum dots after film deposition

    Science.gov (United States)

    Sykora, Milan; Koposov, Alexey; Fuke, Nobuhiro

    2015-02-03

    Provided are methods of surface treatment of nanocrystal quantum dots after film deposition so as to exchange the native ligands of the quantum dots for exchange ligands that result in improvement in charge extraction from the nanocrystals.

  4. Few-quantum-dot lasing in photonic crystal nanocavities

    DEFF Research Database (Denmark)

    Liu, Jin; Ates, Serkan; Stobbe, Søren

    2012-01-01

    A very smooth lasing transition in photonic crystal nanocavities with embedded quantum dots is observed and compared to the theory. Decay rate measurements reveal that only a few quantum dots are feeding the cavity....

  5. Filtering algorithm for dotted interferences

    Energy Technology Data Exchange (ETDEWEB)

    Osterloh, K., E-mail: kurt.osterloh@bam.de [Federal Institute for Materials Research and Testing (BAM), Division VIII.3, Radiological Methods, Unter den Eichen 87, 12205 Berlin (Germany); Buecherl, T.; Lierse von Gostomski, Ch. [Technische Universitaet Muenchen, Lehrstuhl fuer Radiochemie, Walther-Meissner-Str. 3, 85748 Garching (Germany); Zscherpel, U.; Ewert, U. [Federal Institute for Materials Research and Testing (BAM), Division VIII.3, Radiological Methods, Unter den Eichen 87, 12205 Berlin (Germany); Bock, S. [Technische Universitaet Muenchen, Lehrstuhl fuer Radiochemie, Walther-Meissner-Str. 3, 85748 Garching (Germany)

    2011-09-21

    An algorithm has been developed to remove reliably dotted interferences impairing the perceptibility of objects within a radiographic image. This particularly is a major challenge encountered with neutron radiographs collected at the NECTAR facility, Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II): the resulting images are dominated by features resembling a snow flurry. These artefacts are caused by scattered neutrons, gamma radiation, cosmic radiation, etc. all hitting the detector CCD directly in spite of a sophisticated shielding. This makes such images rather useless for further direct evaluations. One approach to resolve this problem of these random effects would be to collect a vast number of single images, to combine them appropriately and to process them with common image filtering procedures. However, it has been shown that, e.g. median filtering, depending on the kernel size in the plane and/or the number of single shots to be combined, is either insufficient or tends to blur sharp lined structures. This inevitably makes a visually controlled processing image by image unavoidable. Particularly in tomographic studies, it would be by far too tedious to treat each single projection by this way. Alternatively, it would be not only more comfortable but also in many cases the only reasonable approach to filter a stack of images in a batch procedure to get rid of the disturbing interferences. The algorithm presented here meets all these requirements. It reliably frees the images from the snowy pattern described above without the loss of fine structures and without a general blurring of the image. It consists of an iterative, within a batch procedure parameter free filtering algorithm aiming to eliminate the often complex interfering artefacts while leaving the original information untouched as far as possible.

  6. Coherence and dephasing in self-assembled quantum dots

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher; Leosson, K.; Birkedal, Dan

    2003-01-01

    We measured dephasing times in InGaAl/As self-assembled quantum dots at low temperature using degenerate four-wave mixing. At 0K, the coherence time of the quantum dots is lifetime limited, whereas at finite temperatures pure dephasing by exciton-phonon interactions governs the quantum dot...... coherence. The inferred homogeneous line widths are significantly smaller than the line widths usually observed in the photoluminescence from single quantum dots indicating an additional inhomogeneours broadening mechanism in the latter....

  7. Modulation Response of Semiconductor Quantum Dot Nanocavity Lasers

    DEFF Research Database (Denmark)

    Lorke, Michael; Nielsen, Torben Roland; Mørk, Jesper

    2011-01-01

    The modulation response of quantum-dot based nanocavity devices is investigated using a semiconductor theory. We show that high modulation bandwidth is achieved even in the presence of inhomogeneous broadening of the quantum dot ensemble.......The modulation response of quantum-dot based nanocavity devices is investigated using a semiconductor theory. We show that high modulation bandwidth is achieved even in the presence of inhomogeneous broadening of the quantum dot ensemble....

  8. Carbon quantum dots and a method of making the same

    Science.gov (United States)

    Zidan, Ragaiy; Teprovich, Joseph A.; Washington, Aaron L.

    2017-08-22

    The present invention is directed to a method of preparing a carbon quantum dot. The carbon quantum dot can be prepared from a carbon precursor, such as a fullerene, and a complex metal hydride. The present invention also discloses a carbon quantum dot made by reacting a carbon precursor with a complex metal hydride and a polymer containing a carbon quantum dot made by reacting a carbon precursor with a complex metal hydride.

  9. Triboelectric Nanogenerators for Blue Energy Harvesting.

    Science.gov (United States)

    Khan, Usman; Kim, Sang-Woo

    2016-07-26

    Blue energy in the form of ocean waves offers an enormous energy resource. However, it has yet to be fully exploited in order to make it available for the use of mankind. Blue energy harvesting is a challenging task as the kinetic energy from ocean waves is irregular in amplitude and is at low frequencies. Though electromagnetic generators (EMGs) are well-known for harvesting mechanical kinetic energies, they have a crucial limitation for blue energy conversion. Indeed, the output voltage of EMGs can be impractically low at the low frequencies of ocean waves. In contrast, triboelectric nanogenerators (TENGs) are highly suitable for blue energy harvesting as they can effectively harvest mechanical energies from low frequencies (energy harvesting. In this Perspective, we describe some of the recent progress and also address concerns related to durable packaging of TENGs in consideration of harsh marine environments and power management for an efficient power transfer and distribution for commercial applications.

  10. Phototherapy with turquoise versus blue light

    OpenAIRE

    Ebbesen, F; Agati, G; Pratesi, R

    2003-01-01

    Preterm jaundiced infants were treated by phototherapy with a new turquoise fluorescent lamp. This was more effective in reducing plasma total bilirubin in relation to light irradiance than the ubiquitously used blue fluorescent lamp.

  11. Reciproc blue: the new generation of reciprocation

    Directory of Open Access Journals (Sweden)

    Ghassan Yared

    2017-11-01

    Conclusions: This article introduces and describes the clinical technique with which the Reciproc® blue instrument is used, even without the need to create a glide path with manual files before using the mechanical instrument.

  12. FROM CIRCULAR ECONOMY TO BLUE ECONOMY

    National Research Council Canada - National Science Library

    Iustin-Emanuel, ALEXANDRU; Alexandru, TASNADI

    2014-01-01

    .... Starting from the principles of Ecolonomy, which is based on the whole living paradigm, this paper argues for the development within each economy of entrepreneurial policies related to the Blue economy...

  13. The Biology of blue-green algae

    National Research Council Canada - National Science Library

    Carr, Nicholas G; Whitton, B. A

    1973-01-01

    .... Their important environmental roles, their part in nitrogen fixation and the biochemistry of phototrophic metabolism are some of the attractions of blue-geen algae to an increasing number of biologists...

  14. Blue-light reception through quaternary transitions

    National Research Council Canada - National Science Library

    Christopher Engelhard; Ralph P Diensthuber; Andreas Möglich; Robert Bittl

    2017-01-01

    .... Using electron-electron double resonance (ELDOR) spectroscopy and site-directed spin labelling, we chart the structural transitions facilitating blue-light reception in the engineered light-oxygen-voltage (LOV...

  15. Substantial Research Secures the Blue Future for our Blue Plant

    Directory of Open Access Journals (Sweden)

    Moustafa Abdel Maksoud

    2016-06-01

    Full Text Available Earth, the blue planet, is our home, and seas and oceans cover more than 70% of its surface. As the earth’s population rapidly increases and available resources decrease, seas and oceans can play a key role in assuring the long-term survival of humankind. Renewable maritime energy has huge potential to provide a considerable part of the earth’s population with decarbonised electricity generation systems. Renewable maritime energy is very flexible and can be harvested above the water’s free surface by using offshore wind turbines, on the water’s surface by using wave energy converters or below the water’s surface by using current or tidal turbines. The supposed conflict between environmental protection measures and economic interests is neither viable nor reasonable. Renewable maritime energy can be the motor for considerable substantial economic growth for many maritime regions and therefore for society at large. The fastest growing sector of renewable maritime energy is offshore wind. The annual report of the European Wind Energy Association from the year 2015 confirms the growing relevance of the offshore wind industry. In 2015, the total installed and grid-connected capacity of wind power was 12,800 MW in the EU and 6,013.4 MW in Germany. 38% of the 2015 annual installation in Germany was offshore, accounting for a capacity of 2,282.4 MW. However, there are a limited number of available installation sites in shallow water, meaning that there is an urgent need to develop new offshore structures for water depths greater than 50m. The persistent trend towards deeper waters has encouraged the offshore wind industry to look for floating wind turbine structures and larger turbines. Floating wind turbine technologies are at an early stage of development and many technical and economic challenges will still need to be faced. Nonetheless, intensive research activities and the employment of advanced technologies are the key factors in

  16. Magnon cotunneling through a quantum dot

    Science.gov (United States)

    Karwacki, Łukasz

    2017-11-01

    I consider a single-level quantum dot coupled to two reservoirs of spin waves (magnons). Such systems have been studied recently from the point of view of possible coupling between electronic and magnonic spin currents. However, usually weakly coupled systems were investigated. When coupling between the dot and reservoirs is not weak, then higher order processes play a role and have to be included. Here I consider cotunneling of magnons through a spin-occupied quantum dot, which can be understood as a magnon (spin) leakage current in analogy to leakage currents in charge-based electronics. Particular emphasis has been put on investigating the effect of magnetic field and temperature difference between the magnonic reservoirs.

  17. Angiogenic Profiling of Synthesized Carbon Quantum Dots.

    Science.gov (United States)

    Shereema, R M; Sruthi, T V; Kumar, V B Sameer; Rao, T P; Shankar, S Sharath

    2015-10-20

    A simple method was employed for the synthesis of green luminescent carbon quantum dots (CQDs) from styrene soot. The CQDs were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared, and Raman spectroscopy. The prepared carbon quantum dots did not show cellular toxicity and could successfully be used for labeling cells. We also evaluated the effects of carbon quantum dots on the process of angiogenesis. Results of a chorioallantoic membrane (CAM) assay revealed the significant decrease in the density of branched vessels after their treatment with CQDs. Further application of CQDs significantly downregulated the expression levels of pro-angiogenic growth factors like VEGF and FGF. Expression of VEGFR2 and levels of hemoglobin were also significantly lower in CAMs treated with CQDs, indicating that the CQDs inhibit angiogenesis. Data presented here also show that CQDs can selectively target cancer cells and therefore hold potential in the field of cancer therapy.

  18. Blue Whales Respond to Anthropogenic Noise

    OpenAIRE

    Melcón, Mariana L.; Amanda J Cummins; Kerosky, Sara M.; Roche, Lauren K.; Wiggins, Sean M.; Hildebrand, John A.

    2012-01-01

    Anthropogenic noise may significantly impact exposed marine mammals. This work studied the vocalization response of endangered blue whales to anthropogenic noise sources in the mid-frequency range using passive acoustic monitoring in the Southern California Bight. Blue whales were less likely to produce calls when mid-frequency active sonar was present. This reduction was more pronounced when the sonar source was closer to the animal, at higher sound levels. The animals were equally likely to...

  19. [The blue jars of Llivia's dispensary].

    Science.gov (United States)

    Tamarelle, Charles

    2007-01-01

    The Town Museum of Llivia, Spanish enclave in Eastern Pyrenees, displays a XVIIIth century dispensary transmitted by a lineage of pharmacists. Decorated plant boxes, Catalonian albarellos (jars) and original items: a reredos shaped toxic cabinet and typical blue albarellos can be seen there. The shape, type and inscriptions of these blue jars are considered through hypothesis about their origin, aesthetic justifications, and the historical and geographic conditions which may infer these specificities.

  20. La distancia psíquica en el ámbito de la selección de mercados internacionales: propuesta de definición y presencia en las PYMEs españolas exportadoras de bienes de consumo = The psychic distance in the field of the international market selection: definition and presence in Spanish SMEs exporters of consumer products

    Directory of Open Access Journals (Sweden)

    Pedro María Martínez Villar

    2016-12-01

    Two relevant issues in the area of export market selection (EMS hereafter converge in this article: to delve into how the decision is constructed, identifying the presence of psychic distance as a limiting factor, and in the absence of a generally accepted definition of psychic distance, offer an eclectic construct duly contrasted. The questionnaire survey is the resource used to obtain the necessary information to achieve the established objectives, and descriptive statistics is the technique used to validate the proposed construct and to know the limitations.  The research focuses on small and medium-sized Spanish exporters of consumer goods because of the relevance they have in the Spanish economy as a whole. Exporters of services or large companies are not included in this study, in one case because of the product and in the other, their resource availability needed a differentiated approach. The decision of SME is complex, by the intervention of the own business strategy and the perception of the psychic distance that the potential markets transmit to the decision makers. In the case of the analyzed sample, the psychic distance acts in the first stages of export circumscribing the EMS to psychically close countries. A psychic-gradualist pattern has been identified that stabilizes when experience moderates the perception of psychic distance. From then on, companies have the precise know-how to address more complex potential markets

  1. Bright infrared LEDs based on colloidal quantum-dots

    KAUST Repository

    Sun, Liangfeng

    2013-01-01

    Record-brightness infrared LEDs based on colloidal quantum-dots have been achieved through control of the spacing between adjacent quantum-dots. By tuning the size of quantum-dots, the emission wavelengths can be tuned between 900nm and 1650nm. © 2013 Materials Research Society.

  2. Electron-hole confinement symmetry in silicon quantum dots

    NARCIS (Netherlands)

    Müller, F.; Mueller, Filipp; Konstantaras, Georgios; Spruijtenburg, P.C.; van der Wiel, Wilfred Gerard; Zwanenburg, Floris Arnoud

    2015-01-01

    We report electrical transport measurements on a gate-defined ambipolar quantum dot in intrinsic silicon. The ambipolarity allows its operation as either an electron or a hole quantum dot of which we change the dot occupancy by 20 charge carriers in each regime. Electron−hole confinement symmetry is

  3. Imaging vasculature and lymphatic flow in mice using quantum dots

    DEFF Research Database (Denmark)

    Ballou, Byron; Ernst, Lauren A.; Andreko, Susan

    2009-01-01

    Quantum dots are ideal probes for fluorescent imaging of vascular and lymphatic tissues. On injection into appropriate sites, red- and near-infrared-emitting quantum dots provide excellent definition of vasculature, lymphoid organs, and lymph nodes draining both normal tissues and tumors. We detail...... methods for use with commercially available quantum dots and discuss common difficulties....

  4. Glowing graphene quantum dots and carbon dots: properties, syntheses, and biological applications.

    Science.gov (United States)

    Zheng, Xin Ting; Ananthanarayanan, Arundithi; Luo, Kathy Qian; Chen, Peng

    2015-04-08

    The emerging graphene quantum dots (GQDs) and carbon dots (C-dots) have gained tremendous attention for their enormous potentials for biomedical applications, owing to their unique and tunable photoluminescence properties, exceptional physicochemical properties, high photostability, biocompatibility, and small size. This article aims to update the latest results in this rapidly evolving field and to provide critical insights to inspire more exciting developments. We comparatively review the properties and synthesis methods of these carbon nanodots and place emphasis on their biological (both fundamental and theranostic) applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Blue space geographies: Enabling health in place.

    Science.gov (United States)

    Foley, Ronan; Kistemann, Thomas

    2015-09-01

    Drawing from research on therapeutic landscapes and relationships between environment, health and wellbeing, we propose the idea of 'healthy blue space' as an important new development Complementing research on healthy green space, blue space is defined as; 'health-enabling places and spaces, where water is at the centre of a range of environments with identifiable potential for the promotion of human wellbeing'. Using theoretical ideas from emotional and relational geographies and critical understandings of salutogenesis, the value of blue space to health and wellbeing is recognised and evaluated. Six individual papers from five different countries consider how health can be enabled in mixed blue space settings. Four sub-themes; embodiment, inter-subjectivity, activity and meaning, document multiple experiences within a range of healthy blue spaces. Finally, we suggest a considerable research agenda - theoretical, methodological and applied - for future work within different forms of blue space. All are suggested as having public health policy relevance in social and public space. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Luminescent carbon quantum dots with high quantum yield as a single white converter for white light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Feng, X. T.; Zhang, Y.; Liu, X. G., E-mail: liuxuguang@tyut.edu.cn [Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Taiyuan 030024 (China); College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Zhang, F.; Wang, Y. L.; Yang, Y. Z., E-mail: yyztyut@126.com [Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Taiyuan 030024 (China); Research Center on Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024 (China)

    2015-11-23

    Carbon quantum dots (CQDs) with high quantum yield (51.4%) were synthesized by a one-step hydrothermal method using thiosalicylic acid and ethylenediamine as precursor. The CQDs have the average diameter of 2.3 nm and possess excitation-independent emission wavelength in the range from 320 to 440 nm excitation. Under an ultraviolet (UV) excitation, the CQDs aqueous solutions emit bright blue fluorescence directly and exhibit broad emission with a high spectral component ratio of 67.4% (blue to red intensity to total intensity). We applied the CQDs as a single white-light converter for white light emitting diodes (WLEDs) using a UV-LED chip as the excitation light source. The resulted WLED shows superior performance with corresponding color temperature of 5227 K and the color coordinates of (0.34, 0.38) belonging to the white gamut.

  7. Magnetoconductivity of quantum dots with Rashba interaction

    Science.gov (United States)

    Lipparini, E.; Barranco, M.; Malet, F.; Pi, M.

    2009-03-01

    We address the magnetoconductivity of a quantum dot with Rashba spin-orbit interaction within linear-response theory. As a consequence of the generalized Kohn’s theorem, the magnetoconductivity of the dot is zero when the spin-orbit coupling is neglected. The inclusion of the spin-orbit interaction violates the mentioned theorem and gives rise to a nonzero magnetoconductivity. We derive a simple expression for this quantity valid up to the second order in the Rashba parameter. In the limit of vanishing lateral confinement, i.e., for a quantum well, a similar calculation yields the quantum Hall-effect result.

  8. Covalent functionalized black phosphorus quantum dots

    Science.gov (United States)

    Scotognella, Francesco; Kriegel, Ilka; Sassolini, Simone

    2018-01-01

    Black phosphorus (BP) nanostructures enable a new strategy to tune the electronic and optical properties of this atomically thin material. In this paper we show, via density functional theory calculations, the possibility to modify the optical properties of BP quantum dots via covalent functionalization. The quantum dot selected in this study has chemical formula P24H12 and has been covalent functionalized with one or more benzene rings or anthracene. The effect of functionalization is highlighted in the absorption spectra, where a red shift of the absorption is noticeable. The shift can be ascribed to an electron delocalization in the black phosphorus/organic molecule nanostructure.

  9. Dot probe performance in two specific phobias.

    Science.gov (United States)

    Wenzel, A; Holt, C S

    1999-11-01

    The present study applied MacLeod, Mathews & Tata's (1986) dot probe attentional deployment methodology to individuals with specific phobias. Attentional deployment towards spider-related, blood-related, positive, negative, and neutral words was examined. Individuals with either spider phobia (N = 13) or blood/injury phobia (N = 14) and non-anxious controls (N = 14) completed the dot probe attentional deployment task. Individuals with specific phobias did not demonstrate an attentional bias towards phobia-related stimuli relevant to their particular fears. Semantic-based information processing paradigms may not be sufficiently potent to demonstrate biased performance towards threatening stimuli in individuals with mild specific phobias who are otherwise healthy.

  10. Cadmium telluride quantum dots advances and applications

    CERN Document Server

    Donegan, John

    2013-01-01

    Optical Properties of Bulk and Nanocrystalline Cadmium Telluride, Núñez Fernández and M.I. VasilevskiyAqueous Synthesis of Colloidal CdTe Nanocrystals, V. Lesnyak, N. Gaponik, and A. EychmüllerAssemblies of Thiol-Capped CdTe Nanocrystals, N. GaponikFörster Resonant Energy Transfer in CdTe Nanocrystal Quantum Dot Structures, M. Lunz and A.L. BradleyEmission of CdTe Nanocrystals Coupled to Microcavities, Y.P. Rakovich and J.F. DoneganBiological Applications of Cadmium Telluride Semiconductor Quantum Dots, A. Le Cign

  11. Mitigation of quantum dot cytotoxicity by microencapsulation.

    Science.gov (United States)

    Romoser, Amelia; Ritter, Dustin; Majitha, Ravish; Meissner, Kenith E; McShane, Michael; Sayes, Christie M

    2011-01-01

    When CdSe/ZnS-polyethyleneimine (PEI) quantum dots (QDs) are microencapsulated in polymeric microcapsules, human fibroblasts are protected from acute cytotoxic effects. Differences in cellular morphology, uptake, and viability were assessed after treatment with either microencapsulated or unencapsulated dots. Specifically, QDs contained in microcapsules terminated with polyethylene glycol (PEG) mitigate contact with and uptake by cells, thus providing a tool to retain particle luminescence for applications such as extracellular sensing and imaging. The microcapsule serves as the "first line of defense" for containing the QDs. This enables the individual QD coating to be designed primarily to enhance the function of the biosensor.

  12. Mitigation of quantum dot cytotoxicity by microencapsulation.

    Directory of Open Access Journals (Sweden)

    Amelia Romoser

    Full Text Available When CdSe/ZnS-polyethyleneimine (PEI quantum dots (QDs are microencapsulated in polymeric microcapsules, human fibroblasts are protected from acute cytotoxic effects. Differences in cellular morphology, uptake, and viability were assessed after treatment with either microencapsulated or unencapsulated dots. Specifically, QDs contained in microcapsules terminated with polyethylene glycol (PEG mitigate contact with and uptake by cells, thus providing a tool to retain particle luminescence for applications such as extracellular sensing and imaging. The microcapsule serves as the "first line of defense" for containing the QDs. This enables the individual QD coating to be designed primarily to enhance the function of the biosensor.

  13. Potential clinical applications of quantum dots

    Science.gov (United States)

    Medintz, Igor L; Mattoussi, Hedi; Clapp, Aaron R

    2008-01-01

    The use of luminescent colloidal quantum dots in biological investigations has increased dramatically over the past several years due to their unique size-dependent optical properties and recent advances in biofunctionalization. In this review, we describe the methods for generating high-quality nanocrystals and report on current and potential uses of these versatile materials. Numerous examples are provided in several key areas including cell labeling, biosensing, in vivo imaging, bimodal magnetic-luminescent imaging, and diagnostics. We also explore toxicity issues surrounding these materials and speculate about the future uses of quantum dots in a clinical setting. PMID:18686776

  14. Spin qubits in graphene quantum dots

    OpenAIRE

    Trauzettel, Björn; Bulaev, Denis V.; Loss, Daniel; Burkard, Guido

    2006-01-01

    We propose how to form spin qubits in graphene. A crucial requirement to achieve this goal is to find quantum dot states where the usual valley degeneracy in bulk graphene is lifted. We show that this problem can be avoided in quantum dots based on ribbons of graphene with semiconducting armchair boundaries. For such a setup, we find the energies and the exact wave functions of bound states, which are required for localized qubits. Additionally, we show that spin qubits in graphene can not on...

  15. Polymers in Carbon Dots: A Review

    Directory of Open Access Journals (Sweden)

    Yiqun Zhou

    2017-02-01

    Full Text Available Carbon dots (CDs have been widely studied since their discovery in 2004 as a green substitute of the traditional quantum dots due to their excellent photoluminescence (PL and high biocompatibility. Meanwhile, polymers have increasingly become an important component for both synthesis and modification of CDs to provide polymeric matrix and enhance their PL property. Furthermore, critical analysis of composites of CDs and polymers has not been available. Herein, in this review, we summarized the use of polymers in the synthesis and functionalization of CDs, and the applications of these CDs in various fields.

  16. Improved dot size uniformity and luminescense of InAs quantum dots on InP substrate

    Science.gov (United States)

    Qiu, Y.; Uhl, D.

    2002-01-01

    InAs self-organized quantum dots have been grown in InGaAs quantum well on InP substrates by metalorganic vapor phase epitaxy. Atomic Force Microscopy confirmed of quantum dot formation with dot density of 3X10(sup 10) cm(sup -2). Improved dot size uniformity and strong room temperature photoluminescence up to 2 micron were observed after modifying the InGaAs well.

  17. The dual roles of functional groups in the photoluminescence of graphene quantum dots

    Science.gov (United States)

    Wang, Shujun; Cole, Ivan S.; Zhao, Dongyuan; Li, Qin

    2016-03-01

    The photoluminescent properties of graphene nanoparticle (named graphene quantum dots) have attracted significant research attention in recent years owing to their profound application potential. However, the photoluminescence (PL) origin of this class of nanocarbons is still unclear. In this paper, combining direct experimental evidence enabled by a facile size-tunable oxygenated graphene quantum dots (GQDs) synthesis method and theoretical calculations, the roles of the aromatic core, functional groups and disordered structures (i.e. defects and sp3 carbon) in the PL of oxygenated GQDs are elucidated in detail. In particular, we found that the functional groups on GQDs play dual roles in the overall emission: (1) they enable π* --> n and σ* --> n transitions, resulting in a molecular type of PL, spectrally invariable with change of particle size or excitation energy; (2) similar to defects and sp3 carbon, functional groups also induce structural deformation to the aromatic core, leading to mid-gap states or, in other words, energy traps, causing π* --> mid-gap states --> π transitions. Therefore, functional groups contribute to both the blue edge and the red shoulder of GQDs' PL spectra. The new insights on the role of functional groups in PL of fluorescent nanocarbons will enable better designs of this new class of materials.The photoluminescent properties of graphene nanoparticle (named graphene quantum dots) have attracted significant research attention in recent years owing to their profound application potential. However, the photoluminescence (PL) origin of this class of nanocarbons is still unclear. In this paper, combining direct experimental evidence enabled by a facile size-tunable oxygenated graphene quantum dots (GQDs) synthesis method and theoretical calculations, the roles of the aromatic core, functional groups and disordered structures (i.e. defects and sp3 carbon) in the PL of oxygenated GQDs are elucidated in detail. In particular, we found

  18. 49 CFR 40.13 - How do DOT drug and alcohol tests relate to non-DOT tests?

    Science.gov (United States)

    2010-10-01

    ... respects. (b) DOT tests must take priority and must be conducted and completed before a non-DOT test is... a blood or urine specimen collected by the employee's physician or a DNA test result purporting to... 49 Transportation 1 2010-10-01 2010-10-01 false How do DOT drug and alcohol tests relate to non...

  19. Comparison of Alcian Blue, Trypan Blue, and Toluidine Blue for Visualization of the Primo Vascular System Floating in Lymph Ducts

    Directory of Open Access Journals (Sweden)

    Da-Un Kim

    2015-01-01

    Full Text Available The primo vascular system (PVS, floating in lymph ducts, was too transparent to be observed by using a stereomicroscope. It was only detectable with the aid of staining dyes, for instance, Alcian blue, which was injected into the lymph nodes. Some dyes were absorbed preferentially by the PVS than the lymph wall. It remains a standing problem to know what dyes are absorbed better by the PVS than the lymph walls. Such information would be useful to unravel the biochemical properties of the PVS that are badly in need for obtaining large amount of PVS specimens. In the current work we tried two other familiar dyes which were used in PVS research before. We found that Trypan blue and toluidine blue did not visualize the PVS. Trypan blue was cleared by the natural washing. Toluidine blue did not stain the PVS, but it did leave stained spots in the lymph wall and its surrounding tissues, and it leaked out of the lymph wall to stain surrounding connective tissues. These completely different behaviors of the three dyes were found for the first time in the current work and provide valuable information to elucidate the mechanism through which some special dyes stained the PVS preferentially compared to the lymphatic wall.

  20. A study of the lunisolar secular resonance $2dot{omega}+dot{Omega}=0$

    Directory of Open Access Journals (Sweden)

    Alessandra eCelletti

    2016-03-01

    Full Text Available The dynamics of small bodies around the Earth has gained a renewed interest,since the awareness of the problems that space debris can cause in thenearby future. A relevant role in space debris is played by lunisolarsecular resonances, which might contribute to an increase of the orbitalelements, typically of the eccentricity. We concentrate our attention onthe lunisolar secular resonance described by the relation$2dot{omega}+dot{Omega}=0$, where $omega$ and $Omega$ denotethe argument of perigee and the longitude of the ascending node of the space debris.We introduce three different models with increasing complexity. We show that the growth in eccentricity, as observed in space debris located in the MEO region at the inclination about equal to $56^circ$, can be explained as a natural effect of the secular resonance $2dot{omega}+dot{Omega}=0$, while the chaotic variations of the orbital parameters are the result of interaction and overlapping of nearby resonances.