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Sample records for pure dysarthria due

  1. Dysarthria

    MedlinePlus

    ... the many types of dysarthria online at The Neuroscience on the Web Series . How is dysarthria diagnosed? ... with the person with dysarthria In severe cases, learning to use alternative means of communication (e.g., ...

  2. Relationship between Kinematics, F2 Slope and Speech Intelligibility in Dysarthria Due to Cerebral Palsy

    ERIC Educational Resources Information Center

    Rong, Panying; Loucks, Torrey; Kim, Heejin; Hasegawa-Johnson, Mark

    2012-01-01

    A multimodal approach combining acoustics, intelligibility ratings, articulography and surface electromyography was used to examine the characteristics of dysarthria due to cerebral palsy (CP). CV syllables were studied by obtaining the slope of F2 transition during the diphthong, tongue-jaw kinematics during the release of the onset consonant,…

  3. Dysarthria - care

    MedlinePlus

    American Speech-Language-Hearing Association. Dysarthria. www.asha.org/public/speech/disorders/dysarthria . Accessed June 27, 2016. Kirshner HS. Dysarthria and apraxia of speech. In: Daroff RB, Jankovic J, Mazziotta JC, ...

  4. Acoustic Characteristics of the Question-Statement Contrast in Severe Dysarthria Due to Cerebral Palsy

    ERIC Educational Resources Information Center

    Patel, Rupal

    2003-01-01

    Studies of prosodic control in severe dysarthria (DYS) have focused on differences between impaired and nonimpaired speech in terms of the range and variation of fundamental frequency (F0), intensity, and duration. Whether individuals with severe DYS can adequately signal prosodic contrasts and "which" acoustic cues they use to do so has received…

  5. Perceptual Ratings of Subgroups of Ataxic Dysarthria

    ERIC Educational Resources Information Center

    Spencer, Kristie A.; France, Ashley A.

    2016-01-01

    Background: The speech characteristics of ataxic dysarthria are known to be quite diverse. The varied presentation of this dysarthria challenges researchers and clinicians alike, and brings into question whether it is a single entity. While the possibility of subtypes of ataxic dysarthria has been suggested, the nature of these putative groups…

  6. Intensive Treatment of Dysarthria Secondary to Stroke

    ERIC Educational Resources Information Center

    Mahler, Leslie A.; Ramig, Lorraine O.

    2012-01-01

    This study investigated the impact of a well-defined behavioral dysarthria treatment on acoustic and perceptual measures of speech in four adults with dysarthria secondary to stroke. A single-subject A-B-A experimental design was used to measure the effects of the Lee Silverman Voice Treatment (LSVT[R]LOUD) on the speech of individual…

  7. Dysarthria

    MedlinePlus

    ... again so you can learn mouth movements To speak slowly, use a louder voice, and pause to ... Lou Gehrig disease) eventually lose the ability to speak. Few people with Parkinson disease or multiple sclerosis ...

  8. Patients' Experiences of Disruptions Associated with Post-Stroke Dysarthria

    ERIC Educational Resources Information Center

    Dickson, Sylvia; Barbour, Rosaline S.; Brady, Marian; Clark, Alexander M.; Paton, Gillian

    2008-01-01

    Background: Post-stroke dysarthria rehabilitation should consider social participation for people with dysarthria, but before this approach can be adopted, an understanding of the psychosocial impact of dysarthria is required. Despite the prevalence of dysarthria as a result of stroke, there is a paucity of research into this communication…

  9. An Acoustic Study of the Relationships among Neurologic Disease, Dysarthria Type, and Severity of Dysarthria

    ERIC Educational Resources Information Center

    Kim, Yunjung; Kent, Raymond D.; Weismer, Gary

    2011-01-01

    Purpose: This study examined acoustic predictors of speech intelligibility in speakers with several types of dysarthria secondary to different diseases and conducted classification analysis solely by acoustic measures according to 3 variables (disease, speech severity, and dysarthria type). Method: Speech recordings from 107 speakers with…

  10. Behavioural Intervention Effects in Dysarthria Following Stroke: Communication Effectiveness, Intelligibility and Dysarthria Impact

    ERIC Educational Resources Information Center

    Mackenzie, Catherine; Lowit, Anja

    2007-01-01

    Background: Dysarthria is a common post-stroke presentation. Its management falls within the remit of the speech and language therapy profession. Little controlled evaluation of the effects of intervention for dysarthria in stroke has been reported. Aims: The study aimed to determine the effects of a period of behavioural communication…

  11. Pure agraphia of kanji due to thrombosis of the Labbé vein.

    PubMed Central

    Yokota, T; Ishiai, S; Furukawa, T; Tsukagoshi, H

    1990-01-01

    A case is described of a 56 year old Japanese male with pure agraphia of kanji (the Japanese morphograms) due to haemorrhagic infarction of the left temporal lobe caused by the rare condition of cortical vein thrombosis of Labbé. Writing kanji was severely impaired without disturbed consciousness, aphasia or apraxia. On the other hand, writing kana (the Japanese syllabograms), and reading kanji and kana were almost intact. This suggests that the process of writing kanji involves a different pathway from that of reading kanji in the left temporal lobe. Pure agraphia of kanji is considered to be similar to lexical agraphia in Indo-European languages, in that the writing system with a poor or irregular phoneme-grapheme transformation is impaired by the left temporal lesion. This case indicates the necessity for considering thrombosis of the Labbé vein when a subcortical haematoma is detected in a temporal lobe on computed tomography of the brain. Images PMID:2341848

  12. Clinical and acoustical variability in hypokinetic dysarthria

    SciTech Connect

    Metter, E.J.; Hanson, W.R.

    1986-10-01

    Ten male patients with parkinsonism secondary to Parkinson's disease or progressive supranuclear palsy had clinical neurological, speech, and acoustical speech evaluations. In addition, seven of the patients were evaluated by x-ray computed tomography (CT) and (F-18)-fluorodeoxyglucose (FDG) positron emission tomography (PET). Extensive variability of speech features, both clinical and acoustical, were found and seemed to be independent of the severity of any parkinsonian sign, CT, or FDG PET. In addition, little relationship existed between the variability across each measured speech feature. What appeared to be important for the appearance of abnormal acoustic measures was the degree of overall severity of the dysarthria. These observations suggest that a better understanding of hypokinetic dysarthria may result from more extensive examination of the variability between patients. Emphasizing a specific feature such as rapid speaking rate in characterizing hypokinetic dysarthria focuses on a single and inconstant finding in a complex speech pattern.

  13. Quantitative Assessment of Interutterance Stability: Application to Dysarthria

    ERIC Educational Resources Information Center

    Cummins, Fred; Lowit, Anja; van Brenk, Frits

    2014-01-01

    Purpose: Following recent attempts to quantify articulatory impairment in speech, the present study evaluates the usefulness of a novel measure of motor stability to characterize dysarthria. Method: The study included 8 speakers with ataxic dysarthria (AD), 16 speakers with hypokinetic dysarthria (HD) as a result of Parkinson's disease, and…

  14. Left-hemispheric dominance for articulation: a prospective study on acute ischaemic dysarthria at different localizations.

    PubMed

    Urban, P P; Rolke, R; Wicht, S; Keilmann, A; Stoeter, P; Hopf, H C; Dieterich, M

    2006-03-01

    Dysarthria is a frequent symptom in cerebral ischaemia. However, speech characteristics of these patients have not previously been investigated in relation to lesion site in a prospective study. We investigated the auditory perceptual features in 62 consecutive patients with dysarthria due to a single, non-space-occupying cerebral infarction confirmed by MRI. Standardized speech samples of all patients were stored within 72 h after stroke onset using a digital tape recorder. Speech samples were assessed independently by two experienced speech therapists, who were unaware of the clinical and neuroradiological findings, using an interval scale ranging from 0 to 6. Separately assessed were features of articulation, phonation, prosody, and the global severity for a total of 31 items. Extracerebellar infarctions (85.5%) were located in the lower motor cortex (14.5%), striatocapsular region (46.8%) and base of the pons (24.2%). Isolated cerebellar infarctions were present in 14.5% of patients. There was a strong correlation between the findings of both examiners, showing identical scores, or only minor differences (<1 on the assessment scale) for 80% of all items. The average severity of dysarthria was 2.9 +/- 1.3. Articulatory abnormalities were the predominant deviation characteristics, affecting in particular the production of consonants. However, phonatory and prosodic abnormalities were also frequently observed speech characteristics. As revealed by factor analysis of speech characteristics the total severity of dysarthria was mainly influenced by the impairment of articulation. Speech parameters describing characteristics of articulation and prosody showed significant side-to-side and area differences, while this effect was lacking for any voice parameter. Left cerebral lesions showed a more severe overall impairment of speech and articulation, independent of lesion topography. Thirty-eight of 62 patients were available for follow-up. Speech evaluation showed

  15. Discriminating Dysarthria Type from Envelope Modulation Spectra

    ERIC Educational Resources Information Center

    Liss, Julie M.; LeGendre, Sue; Lotto, Andrew J.

    2010-01-01

    Purpose: Previous research demonstrated the ability of temporally based rhythm metrics to distinguish among dysarthrias with different prosodic deficit profiles (J. M. Liss et al., 2009). The authors examined whether comparable results could be obtained by an automated analysis of speech envelope modulation spectra (EMS), which quantifies the…

  16. Vowel Acoustics in Dysarthria: Mapping to Perception

    ERIC Educational Resources Information Center

    Lansford, Kaitlin L.; Liss, Julie M.

    2014-01-01

    Purpose: The aim of the present report was to explore whether vowel metrics, demonstrated to distinguish dysarthric and healthy speech in a companion article (Lansford & Liss, 2014), are able to predict human perceptual performance. Method: Vowel metrics derived from vowels embedded in phrases produced by 45 speakers with dysarthria were…

  17. Articulatory Movements during Vowels in Speakers with Dysarthria and Healthy Controls

    ERIC Educational Resources Information Center

    Yunusova, Yana; Weismer, Gary; Westbury, John R.; Lindstrom, Mary J.

    2008-01-01

    Purpose: This study compared movement characteristics of markers attached to the jaw, lower lip, tongue blade, and dorsum during production of selected English vowels by normal speakers and speakers with dysarthria due to amyotrophic lateral sclerosis (ALS) or Parkinson disease (PD). The study asked the following questions: (a) Are movement…

  18. Classifications of Vocalic Segments from Articulatory Kinematics: Healthy Controls and Speakers with Dysarthria

    ERIC Educational Resources Information Center

    Yunusova, Yana; Weismer, Gary G.; Lindstrom, Mary J.

    2011-01-01

    Purpose: In this study, the authors classified vocalic segments produced by control speakers (C) and speakers with dysarthria due to amyotrophic lateral sclerosis (ALS) or Parkinson's disease (PD); classification was based on movement measures. The researchers asked the following questions: (a) Can vowels be classified on the basis of selected…

  19. Vowel Intelligibility in Children with and without Dysarthria: An Exploratory Study

    ERIC Educational Resources Information Center

    Levy, Erika S.; Leone, Dorothy; Moya-Gale, Gemma; Hsu, Sih-Chiao; Chen, Wenli; Ramig, Lorraine O.

    2016-01-01

    Children with dysarthria due to cerebral palsy (CP) present with decreased vowel space area and reduced word intelligibility. Although a robust relationship exists between vowel space and word intelligibility, little is known about the intelligibility of vowels in this population. This exploratory study investigated the intelligibility of American…

  20. Discriminating Dysarthria Type From Envelope Modulation Spectra

    PubMed Central

    Liss, Julie M.; LeGendre, Sue; Lotto, Andrew J.

    2013-01-01

    Purpose Previous research demonstrated the ability of temporally based rhythm metrics to distinguish among dysarthrias with different prosodic deficit profiles (J. M. Liss et al., 2009). The authors examined whether comparable results could be obtained by an automated analysis of speech envelope modulation spectra (EMS), which quantifies the rhythmicity of speech within specified frequency bands. Method EMS was conducted on sentences produced by 43 speakers with 1 of 4 types of dysarthria and healthy controls. The EMS consisted of the spectra of the slow-rate (up to 10 Hz) amplitude modulations of the full signal and 7 octave bands ranging in center frequency from 125 to 8000 Hz. Six variables were calculated for each band relating to peak frequency and amplitude and relative energy above, below, and in the region of 4 Hz. Discriminant function analyses (DFA) determined which sets of predictor variables best discriminated between and among groups. Results Each of 6 DFAs identified 2–6 of the 48 predictor variables. These variables achieved 84%–100% classification accuracy for group membership. Conclusions Dysarthrias can be characterized by quantifiable temporal patterns in acoustic output. Because EMS analysis is automated and requires no editing or linguistic assumptions, it shows promise as a clinical and research tool. PMID:20643800

  1. The "Living with Dysarthria" Group for Post-Stroke Dysarthria: The Participant Voice

    ERIC Educational Resources Information Center

    Mackenzie, C.; Kelly, S.; Paton, G.; Brady, M.; Muir, M.

    2013-01-01

    Background:The "Living with Dysarthria" group programme, devised for people with post-stroke dysarthia and family members, was piloted twice. Feedback from those who experience an intervention contributes to the evaluation of speech and language therapy programmes, giving the participant view of the intervention's value and guiding…

  2. Rate and Loudness Manipulations in Dysarthria: Acoustic and Perceptual Findings.

    ERIC Educational Resources Information Center

    Tjaden, Kris; Wilding, Gregory E.

    2004-01-01

    Both rate reduction and increased loudness reportedly are associated with an increase in the size of the articulatory-acoustic working space and improved acoustic distinctiveness for speakers with dysarthria. Improved intelligibility also has been reported. Few studies have directly compared rate and loudness effects for speakers with dysarthria,…

  3. Breath-Group Intelligibility in Dysarthria: Characteristics and Underlying Correlates

    ERIC Educational Resources Information Center

    Yunusova, Yana; Weismer, Gary; Kent, Ray D.; Rusche, Nicole M.

    2005-01-01

    Purpose: This study was designed to determine whether within-speaker fluctuations in speech intelligibility occurred among speakers with dysarthria who produced a reading passage, and, if they did, whether selected linguistic and acoustic variables predicted the variations in speech intelligibility. Method: Participants with dysarthria included a…

  4. Three-dimensional effects on pure tone fan noise due to inflow distortion. [rotor blade noise prediction

    NASA Technical Reports Server (NTRS)

    Kobayashi, H.

    1978-01-01

    Two dimensional, quasi three dimensional and three dimensional theories for the prediction of pure tone fan noise due to the interaction of inflow distortion with a subsonic annular blade row were studied with the aid of an unsteady three dimensional lifting surface theory. The effects of compact and noncompact source distributions on pure tone fan noise in an annular cascade were investigated. Numerical results show that the strip theory and quasi three-dimensional theory are reasonably adequate for fan noise prediction. The quasi three-dimensional method is more accurate for acoustic power and model structure prediction with an acoustic power estimation error of about plus or minus 2db.

  5. Direct evidence for suppression of the Kondo effect due to pure spin current

    NASA Astrophysics Data System (ADS)

    Hamaya, K.; Kurokawa, T.; Oki, S.; Yamada, S.; Kanashima, T.; Taniyama, T.

    2016-10-01

    We study the effect of a pure spin current on the Kondo singlet in a diluted magnetic alloy using nonlocal lateral spin valve structures with highly spin polarized Co2FeSi electrodes. Temperature dependence of the nonlocal spin signals shows a sharp reduction with decreasing temperature, followed by a plateau corresponding to the low temperature Fermi liquid regime below the Kondo temperature (TK). The spin diffusion length of the Kondo alloy is found to increase with increasing spin accumulation. The results are in agreement with the intuitive description that the Kondo singlet cannot survive any more in sufficiently large spin accumulation even below TK.

  6. Prosodic deviation in dysarthria: a case study.

    PubMed

    Vance, J E

    1994-01-01

    Traditionally, prosodic difficulties in dysarthria have been described in phonetic terms with little attention being paid to the phonological implications of these impairments. This cast study attempts to illustrate the need for a phonological level of analysis. The speech of a 30-year-old ataxic dysarthric is analysed using Crystal's framework and the patterns are discussed in terms of the effect of the phonetic difficulties on the speaker's ability to use his intonation system to mark meaning contrasts. The analysis reveals that this speaker has developed a personal subsystem where he retains some of the features of 'normal' speech and systematically exploits variables still under his control to compensate for other deficits. This study highlights both the value of considering phonological aspects in the analysis of disordered prosody and the need for careful assessment of the appropriacy of the compensatory strategies that have been developed. PMID:8032107

  7. Harry Lee Parker and paroxysmal dysarthria and ataxia

    PubMed Central

    Klaas, James P.; Burkholder, David B.; Singer, Wolfgang

    2013-01-01

    Objective: To review descriptions of paroxysmal dysarthria and ataxia in multiple sclerosis (MS), with special attention given to Parker and his 1946 case series. Methods: Evaluation of original publications describing paroxysmal dysarthria and ataxia, bibliographic information, writings, and unpublished letters from the Mayo Clinic Historical Unit. Results: In 1940, Störring described a patient with MS with paroxysmal symptoms that included dizziness and trouble speaking, but also unilateral extremity weakness. In 1946, Parker published a series of 11 patients with paroxysmal dysarthria and ataxia. Six of these patients had MS, and he recognized this phenomenon as a manifestation of the disease. The term “paroxysmal dysarthria and ataxia” was first used in 1959 by Andermann and colleagues. Since that time, paroxysmal dysarthria and ataxia has become a well-recognized phenomenon in MS. More recent reports have suggested that the responsible lesion is located in the midbrain, near or involving the red nucleus. Conclusions: Parker was the first to accurately describe paroxysmal dysarthria and ataxia in patients with MS. PMID:23319475

  8. Degraded Vowel Acoustics and the Perceptual Consequences in Dysarthria

    NASA Astrophysics Data System (ADS)

    Lansford, Kaitlin L.

    Distorted vowel production is a hallmark characteristic of dysarthric speech, irrespective of the underlying neurological condition or dysarthria diagnosis. A variety of acoustic metrics have been used to study the nature of vowel production deficits in dysarthria; however, not all demonstrate sensitivity to the exhibited deficits. Less attention has been paid to quantifying the vowel production deficits associated with the specific dysarthrias. Attempts to characterize the relationship between naturally degraded vowel production in dysarthria with overall intelligibility have met with mixed results, leading some to question the nature of this relationship. It has been suggested that aberrant vowel acoustics may be an index of overall severity of the impairment and not an "integral component" of the intelligibility deficit. A limitation of previous work detailing perceptual consequences of disordered vowel acoustics is that overall intelligibility, not vowel identification accuracy, has been the perceptual measure of interest. A series of three experiments were conducted to address the problems outlined herein. The goals of the first experiment were to identify subsets of vowel metrics that reliably distinguish speakers with dysarthria from non-disordered speakers and differentiate the dysarthria subtypes. Vowel metrics that capture vowel centralization and reduced spectral distinctiveness among vowels differentiated dysarthric from non-disordered speakers. Vowel metrics generally failed to differentiate speakers according to their dysarthria diagnosis. The second and third experiments were conducted to evaluate the relationship between degraded vowel acoustics and the resulting percept. In the second experiment, correlation and regression analyses revealed vowel metrics that capture vowel centralization and distinctiveness and movement of the second formant frequency were most predictive of vowel identification accuracy and overall intelligibility. The third

  9. Modeling listener perception of speaker similarity in dysarthria.

    PubMed

    Lansford, Kaitlin L; Berisha, Visar; Utianski, Rene L

    2016-06-01

    The current investigation contributes to a perceptual similarity-based approach to dysarthria characterization by utilizing an innovative statistical approach, multinomial logistic regression with sparsity constraints, to identify acoustic features underlying each listener's impressions of speaker similarity. The data-driven approach also permitted an examination of the effect of clinical experience on listeners' impressions of similarity. Listeners, irrespective of level of clinical experience, were found to rely on similar acoustic features during the perceptual sorting task, known as free classification. Overall, the results support the continued advancement of a similarity-based approach to characterizing the communication disorders associated with dysarthria. PMID:27369174

  10. Unusual crystallite growth and modification of ferromagnetism due to aging in pure and doped ZnO nanoparticles

    NASA Astrophysics Data System (ADS)

    Thurber, Aaron P.; Alanko, Gordon; Beausoleil, Geoffrey L.; Dodge, Kelsey N.; Hanna, C. B.; Punnoose, Alex

    2012-04-01

    We report the unusual growth of pure and Fe-doped ZnO nanoparticles prepared by forced hydrolysis and the weakening of ferromagnetism due to aging in ambient conditions. More than four dozen nanoparticle samples in the size range of 4-20 nm were studied over 1 to 4 years. The as-prepared samples had significant changes in their crystallite sizes and magnetization as they aged in ambient conditions. Detailed studies using x ray diffraction and transmission electron microscopy (TEM) demonstrated that the crystallite size increased by as much as 1.4 times. Lattice parameters and strain also showed interesting changes. Magnetometry studies of Zn1-xFexO with x = 0-0.2 showed ferromagnetism at room temperature; however, keeping the samples in ambient conditions for one year resulted in modifications in the crystallite size and magnetization. For the Zn0.95Fe0.05O sample, the size changed from 7.9 nm to 9.0 nm, while the magnetization decreased from 1×10-3emu/g (memu/g) to 0.2 memu/g. Both magnetic and structural changes due to aging varied with the environment in which they were stored, indicating that these changes are related to the aging conditions.

  11. Acoustic Analysis of Voice in Dysarthria following Stroke

    ERIC Educational Resources Information Center

    Wang, Yu-Tsai; Kent, Ray D.; Kent, Jane Finley; Duffy, Joseph R.; Thomas, Jack E.

    2009-01-01

    Although perceptual studies indicate the likelihood of voice disorders in persons with stroke, there have been few objective instrumental studies of voice dysfunction in dysarthria following stroke. This study reports automatic analysis of sustained vowel phonation for 61 speakers with stroke. The results show: (1) men with stroke and healthy…

  12. Perception of Coarticularity Information in Normal Speech and Dysarthria

    ERIC Educational Resources Information Center

    Tjaden, Kris; Sussman, Joan

    2006-01-01

    Purpose: This study addressed three research questions: (a) Can listeners use anticipatory vowel information in prevocalic consonants produced by talkers with dysarthria to identify the upcoming vowel? (b) Are listeners sensitive to interspeaker variation in anticipatory coarticulation during prevocalic consonants produced by healthy talkers…

  13. Voicing Status of Word Final Plosives in Friedreich's Ataxia Dysarthria

    ERIC Educational Resources Information Center

    Blaney, B. E.; Hewlett, N.

    2007-01-01

    In a previous study, the authors identified final plosive voicing contrast as the highest single error source in dysarthria associated with Friedreich's Ataxia in a group of Irish English-speaking participants. This study aimed to determine the acoustic features underlying misperceptions of voicing status and implications for clinical management.…

  14. Dysarthria and Friedreich's Ataxia: What Can Intelligibility Assessment Tell Us?

    ERIC Educational Resources Information Center

    Blaney, Bronagh; Hewlett, Nigel

    2007-01-01

    Background: Friedreich's ataxia is one of the most common hereditary disorders of the nervous system. Dysarthria is a pervasive symptom of Friedreich's ataxia, yet the clinical presentation of speech symptoms remains poorly understood, leaving clinicians without the evidence required to develop therapy interventions. Aims: The research reported…

  15. Vowel Acoustics in Dysarthria: Speech Disorder Diagnosis and Classification

    ERIC Educational Resources Information Center

    Lansford, Kaitlin L.; Liss, Julie M.

    2014-01-01

    Purpose: The purpose of this study was to determine the extent to which vowel metrics are capable of distinguishing healthy from dysarthric speech and among different forms of dysarthria. Method: A variety of vowel metrics were derived from spectral and temporal measurements of vowel tokens embedded in phrases produced by 45 speakers with…

  16. Listener Agreement for Auditory-Perceptual Ratings of Dysarthria

    ERIC Educational Resources Information Center

    Bunton, Kate; Kent, Raymond D.; Duffy, Joseph R.; Rosenbek, John C.; Kent, Jane F.

    2007-01-01

    Purpose: Darley, Aronson, and Brown (1969a, 1969b) detailed methods and results of auditory-perceptual assessment for speakers with dysarthrias of varying etiology. They reported adequate listener reliability for use of the rating system as a tool for differential diagnosis, but several more recent studies have raised concerns about listener…

  17. Characteristics of the Lax Vowel Space in Dysarthria

    ERIC Educational Resources Information Center

    Tjaden, Kris; Rivera, Deanna; Wilding, Gregory; Turner, Greg S.

    2005-01-01

    It has been hypothesized that lax vowels may be relatively unaffected by dysarthria, owing to the reduced vocal tract shapes required for these phonetic events (G. S. Turner, K. Tjaden, & G. Weismer, 1995). It also has been suggested that lax vowels may be especially susceptible to speech mode effects (M. A. Picheny, N. I. Durlach, & L. D. Braida,…

  18. Interarticulator Coordination in Dysarthria: An X-Ray Microbeam Study

    ERIC Educational Resources Information Center

    Weismer, Gary; Yunusova, Yana; Westbury, John R.

    2003-01-01

    Articulatory discoordination is often said to be an important feature of the speech production disorder in dysarthria, but little experimental work has been done to identify and specify the coordination difficulties. The present study evaluated the coordination of labial and lingual gestures for /u/ production in persons with Parkinson's disease…

  19. The scale for the assessment and rating of ataxia correlates with dysarthria assessment in Friedreich's ataxia.

    PubMed

    Eigentler, Andreas; Rhomberg, Johanna; Nachbauer, Wolfgang; Ritzer, Irmgard; Poewe, Werner; Boesch, Sylvia

    2012-03-01

    Dysarthria is an acquired neurogenic sensorimotor speech symptom and an integral part within the clinical spectrum of ataxia syndromes. Ataxia measurements and disability scores generally focus on the assessment of motor functions. Since comprehensive investigations of dysarthria in ataxias are sparse, we assessed dysarthria in ataxia patients using the Frenchay Dysarthria Assessment. The Frenchay Dysarthria Assessment is a ten-item validated test in which eight items focus on the observation of oral structures and speech functions. Fifteen Friedreich's ataxia patients and 15 healthy control individuals were analyzed using clinical and logopedic methodology. All patients underwent neurological assessment applying the Scale for the Assessment and Rating of Ataxia. In Friedreich's ataxia patients, the Frenchay sub-item voice showed to be most affected compared to healthy individuals followed by items such as reflexes, palate, tongue, and intelligibility. Scoring of lips, jaw, and respiration appeared to be mildly affected. Ataxia severity in Friedreich's ataxia patients revealed a significant correlation with the Frenchay dysarthria sum score. The introduction of a binary Adapted Dysarthria Score additionally allowed allocation to distinct dysarthria pattern in ataxias. The Frenchay Dysarthria Assessment proved to be a valid dysarthria measure in Friedreich's ataxia. Its availability in several languages provides a major advantage regarding the applicability in international clinical studies. Shortcomings of the Frenchay test are the multiplicity of items tested and its alphabetic coding. Numerical scoring and condensation of assessments in a modified version may, however, provide an excellent clinical tool for the measurement and scoring of dysarthria in ataxic speech disorders.

  20. The "Living with Dysarthria" Group: Implementation and Feasibility of a Group Intervention for People with Dysarthria Following Stroke and Family Members

    ERIC Educational Resources Information Center

    Mackenzie, Catherine; Paton, Gillian; Kelly, Shona; Brady, Marian; Muir, Margaret

    2012-01-01

    Background: The broad life implications of acquired dysarthria are recognized, but they have received little attention in stroke management. Reports of group therapy, which may be a suitable approach to intervention, are not available for stroke-related dysarthria. Aims: To examine the operational feasibility of and response to a new eight-session…

  1. Automatic Severity Assessment of Dysarthria using State-Specific Vectors.

    PubMed

    Sriranjani, R; Umesh, S; Reddy, M Ramasubba

    2015-01-01

    In this paper, a novel approach to assess the severity of the dysarthria using state-specific vector (SSV) of phone-cluster adaptive training (phone-CAT) acoustic modeling technique is proposed. The dominant component of the SSV represents the actual pronunciations of a speaker. Comparing the dominant component for unimpaired and each dysarthric speaker, a phone confusion matrix is formed. The diagonal elements of the matrix capture the number of correct pronunciations for each dysarthric speaker. As the degree of impairment increases, the number of phones correctly pronounced by the speaker decreases. Thus the trace of the confusion matrix can be used as objective cue to assess di?erent severity levels of dysarthria based on a threshold rule. Our proposed objective measure correlates with the standard Frenchay dysarthric assessment scores by 74 % on Nemours database. The measure also correlates with the intelligibility scores by 82 % on universal access dysarthric speech database. PMID:25996705

  2. Therapeutic Intervention in a Case of Ataxic Dysarthria Associated with a History of Amateur Boxing

    ERIC Educational Resources Information Center

    McMicken, Betty L.; Ostergren, Jennifer A.; Vento-Wilson, Margaret

    2011-01-01

    The goals of this study were to (a) describe the presenting features of ataxic dysarthria present in a participant with a long history of amateur boxing, (b) describe a novel application of behavioral principles in the treatment of this participant, and (c) discuss implications in the treatment of ataxic dysarthria secondary to boxing. The…

  3. Voice Dysfunction in Dysarthria: Application of the Multi-Dimensional Voice Program.

    ERIC Educational Resources Information Center

    Kent, R. D.; Vorperian, H. K.; Kent, J. F.; Duffy, J. R.

    2003-01-01

    Part 1 of this paper recommends procedures and standards for the acoustic analysis of voice in individuals with dysarthria. In Part 2, acoustic data are reviewed for dysarthria associated with Parkinson disease (PD), cerebellar disease, amytrophic lateral sclerosis, traumatic brain injury, unilateral hemispheric stroke, and essential tremor.…

  4. Dysarthria Impact Profile: Development of a Scale to Measure Psychosocial Effects

    ERIC Educational Resources Information Center

    Walshe, Margaret; Peach, Richard K.; Miller, Nick

    2009-01-01

    Background: The psychosocial impact of acquired dysarthria on the speaker is well recognized. To date, speech-and-language therapists have no instrument available to measure this construct. This has implications for outcome measurement and for planning intervention. This paper describes the Dysarthria Impact Profile (DIP), an instrument that has…

  5. Survey of UK Speech and Language Therapists' Assessment and Treatment Practices for People with Progressive Dysarthria

    ERIC Educational Resources Information Center

    Collis, Jessica; Bloch, Steven

    2012-01-01

    Background: Dysarthria knowledge is predominantly impairment-based. As a result, speech and language therapists (SLTs) have traditionally adopted impairment-focused management practices. However, guidance for best practice suggests that SLTs should consider the client holistically, including the impact of dysarthria beyond the impairment. Aims: To…

  6. Non-Speech Oro-Motor Exercise Use in Acquired Dysarthria Management: Regimes and Rationales

    ERIC Educational Resources Information Center

    Mackenzie, Catherine; Muir, Margaret; Allen, Carolyn

    2010-01-01

    Background: Non-speech oro-motor exercises (NSOMExs) are described in speech and language therapy manuals and are thought to be much used in acquired dysarthria intervention, though there is no robust evidence of an influence on speech outcome. Opinions differ as to whether, and for which dysarthria presentations, NSOMExs are appropriate. Aims:…

  7. Dysarthria in Adults with Cerebral Palsy: Clinical Presentation and Impacts on Communication

    ERIC Educational Resources Information Center

    Schölderle, Theresa; Staiger, Anja; Lampe, Renée; Strecker, Katrin; Ziegler, Wolfram

    2016-01-01

    Purpose: Although dysarthria affects the large majority of individuals with cerebral palsy (CP) and can substantially complicate everyday communication, previous research has provided an incomplete picture of its clinical features. We aimed to comprehensively describe characteristics of dysarthria in adults with CP and to elucidate the impact of…

  8. The impact of rate reduction and increased vocal intensity on coarticulation in dysarthria

    NASA Astrophysics Data System (ADS)

    Tjaden, Kris

    2003-04-01

    The dysarthrias are a group of speech disorders resulting from impairment to nervous system structures important for the motor execution of speech. Although numerous studies have examined how dysarthria impacts articulatory movements or changes in vocal tract shape, few studies of dysarthria consider that articulatory events and their acoustic consequences overlap or are coarticulated in connected speech. The impact of rate, loudness, and clarity on coarticulatory patterns in dysarthria also are poorly understood, although these prosodic manipulations frequently are employed as therapy strategies to improve intelligibility in dysarthria and also are known to affect coarticulatory patterns for at least some neurologically healthy speakers. The current study examined the effects of slowed rate and increased vocal intensity on anticipatory coarticulation for speakers with dysarthria secondary to Multiple Sclerosis (MS), as inferred from the acoustic signal. Healthy speakers were studied for comparison purposes. Three repetitions of twelve target words embedded in the carrier phrase ``It's a -- again'' were produced in habitual, loud, and slow speaking conditions. F2 frequencies and first moment coefficients were used to infer coarticulation. Both group and individual speaker trends will be examined in the data analyses.

  9. Pure red cell aplasia due to parvovirus B19 infection after liver transplantation: A case report and review of the literature

    PubMed Central

    Liang, Ting-Bo; Li, Dong-Lin; Yu, Jun; Bai, Xue-Li; Liang, Liang; Xu, Shi-Guo; Wang, Wei-Lin; Shen, Yan; Zhang, Min; Zheng, Shu-Sen

    2007-01-01

    Pure red cell aplasia (PRCA) due to parvovirus B19 (PVB19) infection after solid organ transplantation has been rarely reported and most of the cases were renal transplant recipients. Few have been described after liver transplantation. Moreover, little information on the management of this easily recurring disease is available at present. We describe the first case of a Chinese liver transplant recipient with PVB19-induced PRCA during immunosuppressive therapy. The patient suffered from progressive anemia with the lowest hemoglobin level of 21 g/L. Bone marrow biopsy showed selectively inhibited erythropoiesis with giant pronormoblasts. Detection of PVB19-DNA in serum with quantitative polymerase chain reaction (PCR) revealed a high level of viral load. After 2 courses of intravenous immunoglobulin (IVIG) therapy, bone marrow erythropoiesis recovered with his hemoglobin level increased to 123 g/L. He had a low-level PVB19 load for a 5-mo follow-up period without recurrence of PRCA, and finally the virus was cleared. Our case indicates that clearance of PVB19 by IVIG in transplant recipients might be delayed after recovery of anemia. PMID:17461508

  10. Management of Non-Progressive Dysarthria: Practice Patterns of Speech and Language Therapists in the Republic of Ireland

    ERIC Educational Resources Information Center

    Conway, Aifric; Walshe, Margaret

    2015-01-01

    Background: Dysarthria is a commonly acquired speech disorder. Rising numbers of people surviving stroke and traumatic brain injury (TBI) mean the numbers of people with non-progressive dysarthria are likely to increase, with increased challenges for speech and language therapists (SLTs), service providers and key stakeholders. The evidence base…

  11. Non-Speech Oro-Motor Exercises in Post-Stroke Dysarthria Intervention: A Randomized Feasibility Trial

    ERIC Educational Resources Information Center

    Mackenzie, C.; Muir, M.; Allen, C.; Jensen, A.

    2014-01-01

    Background: There has been little robust evaluation of the outcome of speech and language therapy (SLT) intervention for post-stroke dysarthria. Non-speech oro-motor exercises (NSOMExs) are a common component of dysarthria intervention. A feasibility study was designed and executed, with participants randomized into two groups, in one of which…

  12. Influence of Familiarity on Identifying Prosodic Vocalizations Produced by Children with Severe Dysarthria

    ERIC Educational Resources Information Center

    Patel, Rupal; Schroeder, Bethany

    2007-01-01

    Familiarity is thought to aid listeners in decoding disordered speech; however, as the speech signal degrades, the "familiarity advantage" becomes less beneficial. Despite highly unintelligible speech sound production, many children with dysarthria vocalize when interacting with familiar caregivers. Perhaps listeners can understand these…

  13. Effects of Sensory Modality Stimulation on the Dysarthria of Cerebral Palsy.

    ERIC Educational Resources Information Center

    Love, Russel J.

    To explore the efficacy of improving the dysarthria of cerebral palsy under conditions of aural stimulation, visual stimulation, and combined aural-visual stimulation, 22 subjects (aged 7.6 to 19.0 years) received intensive stimulation for word limitation for 22 consecutive school days. The 87 words of the Irwin Integrated Articulation Test were…

  14. Telediagnostic Assessment of Intelligibility in Dysarthria: A Pilot Investigation of MVP-Online

    ERIC Educational Resources Information Center

    Ziegler, Wolfram; Zierdt, Andreas

    2008-01-01

    Background: A most important index of functional impairment in dysarthria is "intelligibility". The "Munich Intelligibility Profile" (MVP) is a computer-based method for the assessment of the intelligibility of dysarthric patients. A multi-user online version of MVP is now available. Aims: To describe the structure of MVP-online and to evaluate…

  15. The effects of familiarization on intelligibility and lexical segmentation in hypokinetic and ataxic dysarthria

    NASA Astrophysics Data System (ADS)

    Liss, Julie M.; Spitzer, Stephanie M.; Caviness, John N.; Adler, Charles

    2002-12-01

    This study is the third in a series that has explored the source of intelligibility decrement in dysarthria by jointly considering signal characteristics and the cognitive-perceptual processes employed by listeners. A paradigm of lexical boundary error analysis was used to examine this interface by manipulating listener constraints with a brief familiarization procedure. If familiarization allows listeners to extract relevant segmental and suprasegmental information from dysarthric speech, they should obtain higher intelligibility scores than nonfamiliarized listeners, and their lexical boundary error patterns should approximate those obtained in misperceptions of normal speech. Listeners transcribed phrases produced by speakers with either hypokinetic or ataxic dysarthria after being familiarized with other phrases produced by these speakers. Data were compared to those of nonfamiliarized listeners [Liss et al., J. Acoust. Soc. Am. 107, 3415-3424 (2000)]. The familiarized groups obtained higher intelligibility scores than nonfamiliarized groups, and the effects were greater when the dysarthria type of the familiarization procedure matched the dysarthria type of the transcription task. Remarkably, no differences in lexical boundary error patterns were discovered between the familiarized and nonfamiliarized groups. Transcribers of the ataxic speech appeared to have difficulty distinguishing strong and weak syllables in spite of the familiarization. Results suggest that intelligibility decrements arise from the perceptual challenges posed by the degraded segmental and suprasegmental aspects of the signal, but that this type of familiarization process may differentially facilitate mapping segmental information onto existing phonological categories.

  16. Implementing Speech Supplementation Strategies: Effects on Intelligibility and Speech Rate of Individuals with Chronic Severe Dysarthria.

    ERIC Educational Resources Information Center

    Hustad, Katherine C.; Jones, Tabitha; Dailey, Suzanne

    2003-01-01

    A study compared intelligibility and speech rate differences following speaker implementation of 3 strategies (topic, alphabet, and combined topic and alphabet supplementation) and a habitual speech control condition for 5 speakers with severe dysarthria. Combined cues and alphabet cues yielded significantly higher intelligibility scores and…

  17. Articulatory-to-Acoustic Relations in Talkers with Dysarthria: A First Analysis

    ERIC Educational Resources Information Center

    Mefferd, Antje

    2015-01-01

    Purpose: The primary purpose of this study was to determine the strength of interspeaker and intraspeaker articulatory-to-acoustic relations of vowel contrast produced by talkers with dysarthria and controls. Methods: Six talkers with amyotrophic lateral sclerosis (ALS), six talkers with Parkinson's disease (PD), and 12 controls repeated a…

  18. Intonation Contrast in Cantonese Speakers with Hypokinetic Dysarthria Associated with Parkinson's Disease

    ERIC Educational Resources Information Center

    Ma, Joan K.-Y.; Whitehill, Tara L.; So, Susanne Y.-S.

    2010-01-01

    Purpose: Speech produced by individuals with hypokinetic dysarthria associated with Parkinson's disease (PD) is characterized by a number of features including impaired speech prosody. The purpose of this study was to investigate intonation contrasts produced by this group of speakers. Method: Speech materials with a question-statement contrast…

  19. Subthalamic Nucleus Stimulation and Dysarthria in Parkinson's Disease: A PET Study

    ERIC Educational Resources Information Center

    Pinto, Serge; Thobois, Stephane; Costes, Nicolas; Le Bars, Didier; Benabid, Alim-Louis; Broussolle, Emmanuel; Pollak, Pierre; Gentil, Michele

    2004-01-01

    In Parkinson's disease, functional imaging studies during limb motor tasks reveal cerebral activation abnormalities that can be reversed by subthalamic nucleus (STN) stimulation. The effect of STN stimulation on parkinsonian dysarthria has not, however, been investigated using PET. The aim of the present study was to evaluate the effect of STN…

  20. The relationship between listener comprehension and intelligibility scores for speakers with dysarthria

    PubMed Central

    Hustad, Katherine C.

    2010-01-01

    Purpose This study examined the relationship between listener comprehension and intelligibility scores for speakers with mild, moderate, severe, and profound dysarthria. Relationships were examined across all speakers and their listeners when severity effects were statistically controlled, within severity groups, and within individual speakers with dysarthria. Method Speech samples were collected from 12 speakers with dysarthria secondary to cerebral palsy. For each speaker, 12 different listeners completed two tasks (for a total of 144 listeners), one task involved making orthographic transcriptions and one task involved answering comprehension questions. Transcriptions were scored for the number of words transcribed correctly; comprehension questions were scored on a 3-point scale according to their accuracy. Results Across all speakers, the correlation between comprehension and intelligibility scores was non-significant when the effects of severity were factored out and residual scores were examined. Within severity groups, the relationship was significant only for the mild group. Within individual speaker groups, the relationship was non-significant for all but two speakers with dysarthria. Conclusions Findings suggest that transcription intelligibility scores do not accurately reflect listener comprehension scores. Measures of both intelligibility and listener comprehension may provide a more complete description of the information-bearing capability of dysarthric speech than either measure alone. PMID:18506035

  1. Parametric Quantitative Acoustic Analysis of Conversation Produced by Speakers with Dysarthria and Healthy Speakers

    ERIC Educational Resources Information Center

    Rosen, Kristin M.; Kent, Raymond D.; Delaney, Amy L.; Duffy, Joseph R.

    2006-01-01

    Purpose: This study's main purpose was to (a) identify acoustic signatures of hypokinetic dysarthria (HKD) that are robust to phonetic variation in conversational speech and (b) determine specific characteristics of the variability associated with HKD. Method: Twenty healthy control (HC) participants and 20 participants with HKD associated with…

  2. The Use of the Mayo Clinic System for Differential Diagnosis of Dysarthria.

    ERIC Educational Resources Information Center

    Simmons, Katharine C.; Mayo, Robert

    1997-01-01

    A survey of 100 speech-language pathologists involved in the assessment and treatment of patients with dysarthria investigated their attitudes toward the Darley, Aronson, and Brown (DAB) method of classification. Results indicated that most clinicians, believing it helps in the design of a treatment protocol, used the DAB classification system.…

  3. Intensive Voice Treatment (LSVT LOUD) for Children with Spastic Cerebral Palsy and Dysarthria

    ERIC Educational Resources Information Center

    Fox, Cynthia Marie; Boliek, Carol Ann

    2012-01-01

    Purpose: The purpose of this study was to examine the effects of an intensive voice treatment (Lee Silverman Voice Treatment, commonly known as LSVT LOUD) for children with spastic cerebral palsy (CP) and dysarthria. Method: A nonconcurrent multiple baseline single-subject design with replication across 5 children with spastic CP was used.…

  4. Re-thinking diagnostic classification of the dysarthrias: a developmental perspective.

    PubMed

    Morgan, A T; Liégeois, F

    2010-01-01

    Acquired childhood dysarthria (ACD) receives little attention in the research literature in contrast with the adult correlate of the disorder. Speech language pathologists working in this field find diagnosis and management challenging, arguably because there is no child-based dysarthria diagnostic classification. Clinicians are either dependent upon developmental speech models that are not specific to dysarthria and that ignore the neural basis of the disorder, or on adult-based neurobehavioural classification systems. Here we consider the necessary elements for developing a clinically useful and empirically driven diagnostic classification system for ACD. The paper is divided into 2 parts. First, we question whether an adult diagnostic model can be validly applied to children. Second, we propose a methodological approach to develop a classification system for ACD. Specifically, we propose that advancing knowledge in neurobehavioural correlations of ACD is contingent upon large-scale studies, likely requiring international collaboration, which pool brain and speech outcome data. Ideally, researchers across centres would apply standard protocols to: (1) characterize speech behaviour, and (2) brain structure, function and connectivity. When enough data is available to achieve statistical power, analysis could determine subgroups of dysarthria defined by speech behaviour. The commonalities of neural profiles of subgroups could then be examined to create an empirically driven theory of brain-behaviour relationships in ACD to underpin the classification system. Clinical diagnosis for children with ACD will remain limited until such data become available. PMID:20424467

  5. Automatic Evaluation of Speech Rhythm Instability and Acceleration in Dysarthrias Associated with Basal Ganglia Dysfunction.

    PubMed

    Rusz, Jan; Hlavnička, Jan; Čmejla, Roman; Růžička, Evžen

    2015-01-01

    Speech rhythm abnormalities are commonly present in patients with different neurodegenerative disorders. These alterations are hypothesized to be a consequence of disruption to the basal ganglia circuitry involving dysfunction of motor planning, programing, and execution, which can be detected by a syllable repetition paradigm. Therefore, the aim of the present study was to design a robust signal processing technique that allows the automatic detection of spectrally distinctive nuclei of syllable vocalizations and to determine speech features that represent rhythm instability (RI) and rhythm acceleration (RA). A further aim was to elucidate specific patterns of dysrhythmia across various neurodegenerative disorders that share disruption of basal ganglia function. Speech samples based on repetition of the syllable /pa/ at a self-determined steady pace were acquired from 109 subjects, including 22 with Parkinson's disease (PD), 11 progressive supranuclear palsy (PSP), 9 multiple system atrophy (MSA), 24 ephedrone-induced parkinsonism (EP), 20 Huntington's disease (HD), and 23 healthy controls. Subsequently, an algorithm for the automatic detection of syllables as well as features representing RI and RA were designed. The proposed detection algorithm was able to correctly identify syllables and remove erroneous detections due to excessive inspiration and non-speech sounds with a very high accuracy of 99.6%. Instability of vocal pace performance was observed in PSP, MSA, EP, and HD groups. Significantly increased pace acceleration was observed only in the PD group. Although not significant, a tendency for pace acceleration was observed also in the PSP and MSA groups. Our findings underline the crucial role of the basal ganglia in the execution and maintenance of automatic speech motor sequences. We envisage the current approach to become the first step toward the development of acoustic technologies allowing automated assessment of rhythm in dysarthrias. PMID:26258122

  6. Deep Brain Stimulation Exacerbates Hypokinetic Dysarthria in a Rat Model of Parkinson's Disease

    PubMed Central

    King, Nathaniel O.; Anderson, Collin J.; Dorval, Alan D.

    2015-01-01

    Motor symptoms of Parkinson's disease (PD) follow the degeneration of dopaminergic neurons in the substantia nigra pars compacta. Deep brain stimulation (DBS) treats some parkinsonian symptoms – tremor, rigidity, and bradykinesia – but may worsen certain medial motor symptoms, including hypokinetic dysarthria. The mechanisms by which DBS exacerbates dysarthria while improving other symptoms are unclear and difficult to study in human patients. In this work, we propose an animal model of DBS-exacerbated dysarthria. We used the unilateral, 6-hydroxydopamine rat model of PD to test the hypothesis that DBS exacerbates quantifiable aspects of vocalization. Mating calls were recorded from sexually-experienced male rats under healthy and parkinsonian conditions, and during DBS of the subthalamic nucleus. Relative to healthy rats, parkinsonian animals made fewer calls with shorter and less complex vocalizations. In the parkinsonian rats, putatively therapeutic DBS further reduced call frequency, duration, and complexity. Interestingly, the individual utterances of parkinsonian rats spanned a greater bandwidth than those of healthy rats, potentially reducing the effectiveness of the vocal signal. This utterance bandwidth was further increased by DBS. We propose that the parkinsonism-associated changes in call frequency, duration, complexity, and dynamic range combine to constitute a rat analog of parkinsonian dysarthria. Because DBS exacerbates the parkinsonism-associated changes in each of these metrics, the subthalamic stimulated 6-hydroxydopamine rat is a good model of DBS-induced hypokinetic dysarthria in PD. This model will help researchers examine how DBS alleviates many motor symptoms of PD, while exacerbating parkinsonian speech deficits that can greatly diminish patient quality of life. PMID:26498277

  7. A curious case of oxaliplatin-induced neurotoxicity: recurrent, self-limiting dysarthria.

    PubMed

    Joseph, Ranjit; Dasanu, Constantin A

    2014-10-01

    This report presents a unique case of oxaliplatin-induced neurotoxicity featuring acute, recurrent, self-limiting dysarthria following multiple subsequent infusions of oxaliplatin. A 65-year-old man started chemotherapy for metastatic pancreatic adenocarcinoma with oxaliplatin-irinotecan-leucovorin-5-fluorouracil (FOLFIRINOX). During the first and subsequent infusions of oxaliplatin, the patient developed episodes of dysarthria that lasted between 2 and 4 h after oxaliplatin infusions, followed by their complete and uneventful resolution. A thorough neurological examination showed no new neurologic deficits except for very fine tongue fasciculations. Recognizing this self-limiting toxic effect of oxaliplatin is important in order to avoid dose reductions that may affect clinical outcomes.

  8. A speech-controlled environmental control system for people with severe dysarthria.

    PubMed

    Hawley, Mark S; Enderby, Pam; Green, Phil; Cunningham, Stuart; Brownsell, Simon; Carmichael, James; Parker, Mark; Hatzis, Athanassios; O'Neill, Peter; Palmer, Rebecca

    2007-06-01

    Automatic speech recognition (ASR) can provide a rapid means of controlling electronic assistive technology. Off-the-shelf ASR systems function poorly for users with severe dysarthria because of the increased variability of their articulations. We have developed a limited vocabulary speaker dependent speech recognition application which has greater tolerance to variability of speech, coupled with a computerised training package which assists dysarthric speakers to improve the consistency of their vocalisations and provides more data for recogniser training. These applications, and their implementation as the interface for a speech-controlled environmental control system (ECS), are described. The results of field trials to evaluate the training program and the speech-controlled ECS are presented. The user-training phase increased the recognition rate from 88.5% to 95.4% (p<0.001). Recognition rates were good for people with even the most severe dysarthria in everyday usage in the home (mean word recognition rate 86.9%). Speech-controlled ECS were less accurate (mean task completion accuracy 78.6% versus 94.8%) but were faster to use than switch-scanning systems, even taking into account the need to repeat unsuccessful operations (mean task completion time 7.7s versus 16.9s, p<0.001). It is concluded that a speech-controlled ECS is a viable alternative to switch-scanning systems for some people with severe dysarthria and would lead, in many cases, to more efficient control of the home. PMID:17049905

  9. Effect of visual biofeedback of posterior tongue movement on articulation rehabilitation in dysarthria patients.

    PubMed

    Yano, J; Shirahige, C; Oki, K; Oisaka, N; Kumakura, I; Tsubahara, A; Minagi, S

    2015-08-01

    Articulation is driven by various combinations of movements of the lip, tongue, soft palate, pharynx and larynx, where the tongue plays an especially important role. In patients with cerebrovascular disorder, lingual motor function is often affected, causing dysarthria. We aimed to evaluate the effect of visual biofeedback of posterior tongue movement on articulation rehabilitation in dysarthria patients with cerebrovascular disorder. Fifteen dysarthria patients (10 men and 5 women; mean age, 70.7 ± 10.3 years) agreed to participate in this study. A device for measuring the movement of the posterior part of the tongue was used for the visual biofeedback. Subjects were instructed to produce repetitive articulation of [ka] as fast and steadily as possible between a lungful with/without visual biofeedback. For both the unaffected and affected sides, the range of ascending and descending movement of the posterior tongue with visual biofeedback was significantly larger than that without visual biofeedback. The coefficient of variation for these movements with visual biofeedback was significantly smaller than that without visual biofeedback. With visual biofeedback, the range of ascent exhibited a significant and strong correlation with that of descent for both the unaffected and affected sides. The results of this study revealed that the use of visual biofeedback leads to prompt and preferable change in the movement of the posterior part of the tongue. From the standpoint of pursuing necessary rehabilitation for patients with attention and memory disorders, visualization of tongue movement would be of marked clinical benefit.

  10. Primary Sjögren syndrome presenting with hemolytic anemia and pure red cell aplasia following delivery due to Coombs-negative autoimmune hemolytic anemia and hemophagocytosis.

    PubMed

    Komaru, Yohei; Higuchi, Takakazu; Koyamada, Ryosuke; Haji, Youichiro; Okada, Masato; Kamesaki, Toyomi; Okada, Sadamu

    2013-01-01

    A 36-year-old woman presented with hemolytic anemia without a reticulocyte response 38 days after delivery. A marked reduction in erythroid cells and an increase in macrophages with active hemophagocytosis were noted in the bone marrow. While conventional Coombs' tests were negative, the level of red blood cell (RBC)-bound immunoglobulin G (IgG) was increased. The patient was diagnosed with primary Sjögren syndrome (pSS) based on her symptoms, positive anti-SS-A antibodies, Coombs-negative autoimmune hemolytic anemia and pure red cell aplasia associated with RBC-bound IgG and hemophagocytosis. The unique presentation was considered to be a consequence of immunological derangement associated with pSS, pregnancy and delivery.

  11. Pure-quartic solitons

    PubMed Central

    Blanco-Redondo, Andrea; Martijn, de Sterke C.; Sipe, J.E.; Krauss, Thomas F.; Eggleton, Benjamin J.; Husko, Chad

    2016-01-01

    Temporal optical solitons have been the subject of intense research due to their intriguing physics and applications in ultrafast optics and supercontinuum generation. Conventional bright optical solitons result from the interaction of anomalous group-velocity dispersion and self-phase modulation. Here we experimentally demonstrate a class of bright soliton arising purely from the interaction of negative fourth-order dispersion and self-phase modulation, which can occur even for normal group-velocity dispersion. We provide experimental and numerical evidence of shape-preserving propagation and flat temporal phase for the fundamental pure-quartic soliton and periodically modulated propagation for the higher-order pure-quartic solitons. We derive the approximate shape of the fundamental pure-quartic soliton and discover that is surprisingly Gaussian, exhibiting excellent agreement with our experimental observations. Our discovery, enabled by precise dispersion engineering, could find applications in communications, frequency combs and ultrafast lasers. PMID:26822758

  12. Pure-quartic solitons.

    PubMed

    Blanco-Redondo, Andrea; de Sterke, C Martijn; Martijn, de Sterke C; Sipe, J E; Krauss, Thomas F; Eggleton, Benjamin J; Husko, Chad

    2016-01-01

    Temporal optical solitons have been the subject of intense research due to their intriguing physics and applications in ultrafast optics and supercontinuum generation. Conventional bright optical solitons result from the interaction of anomalous group-velocity dispersion and self-phase modulation. Here we experimentally demonstrate a class of bright soliton arising purely from the interaction of negative fourth-order dispersion and self-phase modulation, which can occur even for normal group-velocity dispersion. We provide experimental and numerical evidence of shape-preserving propagation and flat temporal phase for the fundamental pure-quartic soliton and periodically modulated propagation for the higher-order pure-quartic solitons. We derive the approximate shape of the fundamental pure-quartic soliton and discover that is surprisingly Gaussian, exhibiting excellent agreement with our experimental observations. Our discovery, enabled by precise dispersion engineering, could find applications in communications, frequency combs and ultrafast lasers. PMID:26822758

  13. Listener deficits in hypokinetic dysarthria: Which cues are most important in speech segmentation?

    NASA Astrophysics Data System (ADS)

    Wade, Carolyn Ann

    Listeners use prosodic cues to help them quickly process running speech. In English, listeners effortlessly use strong syllables to help them to find words in the continuous stream of speech produced by neurologically-intact individuals. However, listeners are not always presented with speech under such ideal circumstances. This thesis explores the question of word segmentation of English speech under one of these less ideal conditions; specifically, when the speaker may be impaired in his/her production of strong syllables, as in the case of hypokinetic dysarthria. Further, we attempt to discern which acoustic cue(s) are most degraded in hypokinetic dysarthria and the effect that this degradation has on listeners' segmentation when no additional semantic or pragmatic cues are present. Two individuals with Parkinson's disease, one with a rate disturbance and one with articulatory disruption, along with a typically aging control, were recorded repeating a series of nonsense syllables. Young adult listeners were then presented with recordings from one of these three speakers producing non-words (imprecise consonant articulation, rate disturbance, and control). After familiarization, the listeners were asked to rate the familiarity of the non-words produced by a second typically aging speaker. Results indicated speakers with hypokinetic dysarthria were able to modulate their intensity and duration for stressed and unstressed syllables in a way similar to that of control speakers. In addition, their mean and peak fundamental frequency for both stressed and unstressed syllables were significantly higher than that of the normally aging controls. ANOVA results revealed a marginal main effect of frequency in normal and consonant conditions for word versus nonwords listener ratings.

  14. When the word doesn't come out: A synthetic overview of dysarthria.

    PubMed

    Rampello, Liborio; Rampello, Luigi; Patti, Francesco; Zappia, Mario

    2016-10-15

    Motor speech disorders are common in a number of neurological conditions including diseases involving impairment of the pyramidal, extrapyramidal, and cerebellar pathways, cranial nerves, muscular apparatus, neuromuscular plaque, and of cognitive, symbolic and mnestic activities. The diagnosis of speech disorders, namely the dysarthrias, involves the assessment of characteristic structural cerebral, prosodic, phonetic and phonemic changes, often flanked by concomitant functional, clinical, neuroradiological, neurophysiological and behavioral impairment. This paper presents a brief outline of the most significant associations to facilitate prompt differential diagnosis and thereby reduce the number of instrumental examinations required for diagnostic testing. PMID:27653923

  15. Lymphangiomatous Polyp of Palatine Tonsil in A Child Presenting with Dysphagia and Dysarthria

    PubMed Central

    Khatib, Yasmeen; Gite, Vinod; Shoeb, Mohammed; Oraon, Asha

    2015-01-01

    Pedunculated lymphangiomatous polyps of the tonsil are rare benign lesions that have been described in literature using varied nomenclature. Majority of the cases have been reported in adults with varying clinical symptoms. We report a case of lymphangiomatous polyp of left palatine tonsil in a 14-year-old male child who presented with dysphagia and dysarthria. Clinical examination revealed a large pedunculated polyp arising from upper pole of left tonsil. Patient underwent left tonsillectomy with excision of the polyp. Based on histopathological features a diagnosis of pedunculated lymphangiomatous polyp was made. We discuss the clinical and histopathological features of this lesion with differential diagnosis and short review of literature. PMID:26155482

  16. The Effects of Topic Knowledge on Intelligibility and Lexical Segmentation in Hypokinetic and Ataxic Dysarthria

    PubMed Central

    Utianski, Rene L.; Lansford, Kaitlin L.; Liss, Julie M.; Azuma, Tamiko

    2013-01-01

    Benefits to speech intelligibility can be achieved by enhancing a listener’s ability to decipher it. However, much remains to be learned about the variables that influence the effectiveness of various listener-based manipulations. This study examined the benefit of providing listeners with the topic of some phases produced by speakers with either hypokinetic or ataxic dysarthria. Total and topic word accuracy, topic-related substitutions, and lexical boundary errors were calculated from the listener transcripts. Data were compared with those who underwent a familiarization process (reported by Liss, Spitzer, Caviness, & Adler, 2002) and with those inexperienced with disordered speech (reported by Liss Spitzer, Caviness, & Adler, 2000). Results revealed that listeners of ataxic speech provided with topic knowledge obtained higher intelligibility scores than naïve listeners. The magnitude of benefit was similar to the familiarization condition. However, topic word and word substitution analyses revealed different underlying perceptual mechanisms responsible for the observed benefit. No differences attributable to listening condition were discovered in lexical segmentation patterns. Overall, the results support the need for further study of listener-based manipulations to elucidate the mechanisms responsible for the observed perceptual benefits for each dysarthria type. PMID:24569812

  17. Pure shift NMR.

    PubMed

    Zangger, Klaus

    2015-04-01

    Although scalar-coupling provides important structural information, the resulting signal splittings significantly reduce the resolution of NMR spectra. Limited resolution is a particular problem in proton NMR experiments, resulting in part from the limited proton chemical shift range (∼10 ppm) but even more from the splittings due to scalar coupling to nearby protons. "Pure shift" NMR spectroscopy (also known as broadband homonuclear decoupling) has been developed for disentangling overlapped proton NMR spectra. The resulting spectra are considerably simplified as they consist of single lines, reminiscent of proton-decoupled C-13 spectra at natural abundance, with no multiplet structure. The different approaches to obtaining pure shift spectra are reviewed here and several applications presented. Pure shift spectra are especially useful for highly overlapped proton spectra, as found for example in reaction mixtures, natural products and biomacromolecules.

  18. Role of Cerebellum in Fine Speech Control in Childhood: Persistent Dysarthria after Surgical Treatment for Posterior Fossa Tumour

    ERIC Educational Resources Information Center

    Morgan, A. T.; Liegeois, F.; Liederkerke, C.; Vogel, A. P.; Hayward, R.; Harkness, W.; Chong, K.; Vargha-Khadem, F.

    2011-01-01

    Dysarthria following surgical resection of childhood posterior fossa tumour (PFT) is most commonly documented in a select group of participants with mutism in the acute recovery phase, thus limiting knowledge of post-operative prognosis for this population of children as a whole. Here we report on the speech characteristics of 13 cases seen…

  19. Study of accent-based music speech protocol development for improving voice problems in stroke patients with mixed dysarthria.

    PubMed

    Kim, Soo Ji; Jo, Uiri

    2013-01-01

    Based on the anatomical and functional commonality between singing and speech, various types of musical elements have been employed in music therapy research for speech rehabilitation. This study was to develop an accent-based music speech protocol to address voice problems of stroke patients with mixed dysarthria. Subjects were 6 stroke patients with mixed dysarthria and they received individual music therapy sessions. Each session was conducted for 30 minutes and 12 sessions including pre- and post-test were administered for each patient. For examining the protocol efficacy, the measures of maximum phonation time (MPT), fundamental frequency (F0), average intensity (dB), jitter, shimmer, noise to harmonics ratio (NHR), and diadochokinesis (DDK) were compared between pre and post-test and analyzed with a paired sample t-test. The results showed that the measures of MPT, F0, dB, and sequential motion rates (SMR) were significantly increased after administering the protocol. Also, there were statistically significant differences in the measures of shimmer, and alternating motion rates (AMR) of the syllable /K$\\inve$/ between pre- and post-test. The results indicated that the accent-based music speech protocol may improve speech motor coordination including respiration, phonation, articulation, resonance, and prosody of patients with dysarthria. This suggests the possibility of utilizing the music speech protocol to maximize immediate treatment effects in the course of a long-term treatment for patients with dysarthria.

  20. Acoustic and Perceptual Effects of Dysarthria in Greek with a Focus on Lexical Stress

    NASA Astrophysics Data System (ADS)

    Papakyritsis, Ioannis

    The field of motor speech disorders in Greek is substantially underresearched. Additionally, acoustic studies on lexical stress in dysarthria are generally very rare (Kim et al. 2010). This dissertation examined the acoustic and perceptual effects of Greek dysarthria focusing on lexical stress. Additional possibly deviant speech characteristics were acoustically analyzed. Data from three dysarthric participants and matched controls was analyzed using a case study design. The analysis of lexical stress was based on data drawn from a single word repetition task that included pairs of disyllabic words differentiated by stress location. This data was acoustically analyzed in terms of the use of the acoustic cues for Greek stress. The ability of the dysarthric participants to signal stress in single words was further assessed in a stress identification task carried out by 14 naive Greek listeners. Overall, the acoustic and perceptual data indicated that, although all three dysarthric speakers presented with some difficulty in the patterning of stressed and unstressed syllables, each had different underlying problems that gave rise to quite distinct patterns of deviant speech characteristics. The atypical use of lexical stress cues in Anna's data obscured the prominence relations of stressed and unstressed syllables to the extent that the position of lexical stress was usually not perceptually transparent. Chris and Maria on the other hand, did not have marked difficulties signaling lexical stress location, although listeners were not 100% successful in the stress identification task. For the most part, Chris' atypical phonation patterns and Maria's very slow rate of speech did not interfere with lexical stress signaling. The acoustic analysis of the lexical stress cues was generally in agreement with the participants' performance in the stress identification task. Interestingly, in all three dysarthric participants, but more so in Anna, targets stressed on the 1st

  1. Impact of cognitive function and dysarthria on spoken language and perceived speech severity in multiple sclerosis

    NASA Astrophysics Data System (ADS)

    Feenaughty, Lynda

    Purpose: The current study sought to investigate the separate effects of dysarthria and cognitive status on global speech timing, speech hesitation, and linguistic complexity characteristics and how these speech behaviors impose on listener impressions for three connected speech tasks presumed to differ in cognitive-linguistic demand for four carefully defined speaker groups; 1) MS with cognitive deficits (MSCI), 2) MS with clinically diagnosed dysarthria and intact cognition (MSDYS), 3) MS without dysarthria or cognitive deficits (MS), and 4) healthy talkers (CON). The relationship between neuropsychological test scores and speech-language production and perceptual variables for speakers with cognitive deficits was also explored. Methods: 48 speakers, including 36 individuals reporting a neurological diagnosis of MS and 12 healthy talkers participated. The three MS groups and control group each contained 12 speakers (8 women and 4 men). Cognitive function was quantified using standard clinical tests of memory, information processing speed, and executive function. A standard z-score of ≤ -1.50 indicated deficits in a given cognitive domain. Three certified speech-language pathologists determined the clinical diagnosis of dysarthria for speakers with MS. Experimental speech tasks of interest included audio-recordings of an oral reading of the Grandfather passage and two spontaneous speech samples in the form of Familiar and Unfamiliar descriptive discourse. Various measures of spoken language were of interest. Suprasegmental acoustic measures included speech and articulatory rate. Linguistic speech hesitation measures included pause frequency (i.e., silent and filled pauses), mean silent pause duration, grammatical appropriateness of pauses, and interjection frequency. For the two discourse samples, three standard measures of language complexity were obtained including subordination index, inter-sentence cohesion adequacy, and lexical diversity. Ten listeners

  2. Small intragenic deletion in FOXP2 associated with childhood apraxia of speech and dysarthria.

    PubMed

    Turner, Samantha J; Hildebrand, Michael S; Block, Susan; Damiano, John; Fahey, Michael; Reilly, Sheena; Bahlo, Melanie; Scheffer, Ingrid E; Morgan, Angela T

    2013-09-01

    Relatively little is known about the neurobiological basis of speech disorders although genetic determinants are increasingly recognized. The first gene for primary speech disorder was FOXP2, identified in a large, informative family with verbal and oral dyspraxia. Subsequently, many de novo and familial cases with a severe speech disorder associated with FOXP2 mutations have been reported. These mutations include sequencing alterations, translocations, uniparental disomy, and genomic copy number variants. We studied eight probands with speech disorder and their families. Family members were phenotyped using a comprehensive assessment of speech, oral motor function, language, literacy skills, and cognition. Coding regions of FOXP2 were screened to identify novel variants. Segregation of the variant was determined in the probands' families. Variants were identified in two probands. One child with severe motor speech disorder had a small de novo intragenic FOXP2 deletion. His phenotype included features of childhood apraxia of speech and dysarthria, oral motor dyspraxia, receptive and expressive language disorder, and literacy difficulties. The other variant was found in a family in two of three family members with stuttering, and also in the mother with oral motor impairment. This variant was considered a benign polymorphism as it was predicted to be non-pathogenic with in silico tools and found in database controls. This is the first report of a small intragenic deletion of FOXP2 that is likely to be the cause of severe motor speech disorder associated with language and literacy problems.

  3. Impact of cognitive function and dysarthria on spoken language and perceived speech severity in multiple sclerosis

    NASA Astrophysics Data System (ADS)

    Feenaughty, Lynda

    Purpose: The current study sought to investigate the separate effects of dysarthria and cognitive status on global speech timing, speech hesitation, and linguistic complexity characteristics and how these speech behaviors impose on listener impressions for three connected speech tasks presumed to differ in cognitive-linguistic demand for four carefully defined speaker groups; 1) MS with cognitive deficits (MSCI), 2) MS with clinically diagnosed dysarthria and intact cognition (MSDYS), 3) MS without dysarthria or cognitive deficits (MS), and 4) healthy talkers (CON). The relationship between neuropsychological test scores and speech-language production and perceptual variables for speakers with cognitive deficits was also explored. Methods: 48 speakers, including 36 individuals reporting a neurological diagnosis of MS and 12 healthy talkers participated. The three MS groups and control group each contained 12 speakers (8 women and 4 men). Cognitive function was quantified using standard clinical tests of memory, information processing speed, and executive function. A standard z-score of ≤ -1.50 indicated deficits in a given cognitive domain. Three certified speech-language pathologists determined the clinical diagnosis of dysarthria for speakers with MS. Experimental speech tasks of interest included audio-recordings of an oral reading of the Grandfather passage and two spontaneous speech samples in the form of Familiar and Unfamiliar descriptive discourse. Various measures of spoken language were of interest. Suprasegmental acoustic measures included speech and articulatory rate. Linguistic speech hesitation measures included pause frequency (i.e., silent and filled pauses), mean silent pause duration, grammatical appropriateness of pauses, and interjection frequency. For the two discourse samples, three standard measures of language complexity were obtained including subordination index, inter-sentence cohesion adequacy, and lexical diversity. Ten listeners

  4. Small intragenic deletion in FOXP2 associated with childhood apraxia of speech and dysarthria.

    PubMed

    Turner, Samantha J; Hildebrand, Michael S; Block, Susan; Damiano, John; Fahey, Michael; Reilly, Sheena; Bahlo, Melanie; Scheffer, Ingrid E; Morgan, Angela T

    2013-09-01

    Relatively little is known about the neurobiological basis of speech disorders although genetic determinants are increasingly recognized. The first gene for primary speech disorder was FOXP2, identified in a large, informative family with verbal and oral dyspraxia. Subsequently, many de novo and familial cases with a severe speech disorder associated with FOXP2 mutations have been reported. These mutations include sequencing alterations, translocations, uniparental disomy, and genomic copy number variants. We studied eight probands with speech disorder and their families. Family members were phenotyped using a comprehensive assessment of speech, oral motor function, language, literacy skills, and cognition. Coding regions of FOXP2 were screened to identify novel variants. Segregation of the variant was determined in the probands' families. Variants were identified in two probands. One child with severe motor speech disorder had a small de novo intragenic FOXP2 deletion. His phenotype included features of childhood apraxia of speech and dysarthria, oral motor dyspraxia, receptive and expressive language disorder, and literacy difficulties. The other variant was found in a family in two of three family members with stuttering, and also in the mother with oral motor impairment. This variant was considered a benign polymorphism as it was predicted to be non-pathogenic with in silico tools and found in database controls. This is the first report of a small intragenic deletion of FOXP2 that is likely to be the cause of severe motor speech disorder associated with language and literacy problems. PMID:23918746

  5. Clinical predictors of lacunar syndrome not due to lacunar infarction

    PubMed Central

    2010-01-01

    Background Lacunar syndrome not due to lacunar infarct is poorly characterised. This single centre, retrospective study was conducted to describe the clinical characteristics of patients with lacunar syndrome not due to lacunar infarct and to identify clinical predictors of this variant of lacunar stroke. Methods A total of 146 patients with lacunar syndrome not due to lacunar infarction were included in the "Sagrat Cor Hospital of Barcelona Stroke Registry" during a period of 19 years (1986-2004). Data from stroke patients are entered in the stroke registry following a standardized protocol with 161 items regarding demographics, risk factors, clinical features, laboratory and neuroimaging data, complications and outcome. The characteristics of these 146 patients with lacunar syndrome not due to lacunar infarct were compared with those of the 733 patients with lacunar infarction. Results Lacunar syndrome not due to lacunar infarct accounted for 16.6% (146/879) of all cases of lacunar stroke. Subtypes of lacunar syndromes included pure motor stroke in 63 patients, sensorimotor stroke in 51, pure sensory stroke in 14, atypical lacunar syndrome in 9, ataxic hemiparesis in 5 and dysarthria-clumsy hand in 4. Valvular heart disease, atrial fibrillation, sudden onset, limb weakness and sensory symptoms were significantly more frequent among patients with lacunar syndrome not due to lacunar infarct than in those with lacunar infarction, whereas diabetes was less frequent. In the multivariate analysis, atrial fibrillation (OR = 4.62), sensorimotor stroke (OR = 4.05), limb weakness (OR = 2.09), sudden onset (OR = 2.06) and age (OR = 0.96) were independent predictors of lacunar syndrome not due to lacunar infarct. Conclusions Although lacunar syndromes are highly suggestive of small deep cerebral infarctions, lacunar syndromes not due to lacunar infarcts are found in 16.6% of cases. The presence of sensorimotor stroke, limb weakness and sudden onset in a patient with atrial

  6. Twisted partially pure spinors

    NASA Astrophysics Data System (ADS)

    Herrera, Rafael; Tellez, Ivan

    2016-08-01

    Motivated by the relationship between orthogonal complex structures and pure spinors, we define twisted partially pure spinors in order to characterize spinorially subspaces of Euclidean space endowed with a complex structure.

  7. Multiple Factors Are Involved in the Dysarthria Associated with Parkinson's Disease: A Review with Implications for Clinical Practice and Research

    ERIC Educational Resources Information Center

    Sapir, Shimon

    2014-01-01

    Purpose: Motor speech abnormalities are highly common and debilitating in individuals with idiopathic Parkinson's disease (IPD). These abnormalities, collectively termed hypokinetic dysarthria (HKD), have been traditionally attributed to hypokinesia and bradykinesia secondary to muscle rigidity and dopamine deficits. However, the role of…

  8. Effectiveness of Lee Silverman Voice Treatment (LSVT)[R] on Hypernasality in Non-Progressive Dysarthria: The Need for Further Research

    ERIC Educational Resources Information Center

    Wenke, Rachel J.; Theodoros, Deborah; Cornwell, Petrea

    2010-01-01

    Background: Hypernasality is a common feature of non-progressive dysarthria. However, limited research has investigated the effectiveness of treatments for this impairment. Preliminary research has revealed positive effects on nasalance when using increased loudness in certain non-progressive dysarthric speakers. However, the long-term effects of…

  9. Bilateral Vestibulopathy Aggravates Balance and Gait Disturbances in Sensory Ataxic Neuropathy, Dysarthria, and Ophthalmoparesis: A Case Report.

    PubMed

    van Leeuwen, Roeland B; Smits, Bart W; Rodenburg, Richard J; van Engelen, Baziel G

    2016-09-01

    In patients with a triad of sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (SANDO), the presenting features are mainly ataxia or ptosis. SANDO patients often have impaired balance and gait, which is not surprising considering the combination of sensory ataxic neuropathy, and additional symptoms like cerebellar ataxia and limb girdle weakness. We describe a SANDO patient who noticed an increasingly impaired balance and gait, without any dizziness. Neurological investigation revealed an external ophthalmeplegia and a cerebellar ataxia; the head impulse test was not reliable because of eye movement disorders. The caloric reflex tests showed lack of responses on both sides, compatible with severe bilateral vestibulopathy. Making the diagnosis of bilateral vestibulopathy in SANDO patients may have implications for the management of the patient, because specific vestibular rehabilitation can improve gaze and postural stability. PMID:27552387

  10. Purely lytic osteosarcoma

    SciTech Connect

    De Santos, L.A.; Eideken, B.

    1982-11-01

    The radiographic features of 42 purely lytic osteosarcomas are presented. Purely lytic osteosarcoma is identified as a lytic lesion of bone with no demonstrable osteoid matrix by conventional radiographic modalities. Purely lytic osteosarcoma represented 13.7% of a group of 305 osteosarcomas. The most common presentation was that of a lytic illdefined lesion with a moderate to large extraosseous mass component. Nine lesions presented with benign radiographic features. The differential diagnosis is outlined. The need for awareness of this type of presentation of osteosarcoma is stressed.

  11. Geomorphology: Pure and applied

    SciTech Connect

    Hart, M.G.

    1986-01-01

    The book summarizes the history of intellectual debate in geomorphology and describes modern developments both ''pure'' and ''applied.'' The history begins well before W.M. Davis and follows through to such debates as those concerned with the Pleistocene. Modern developments in pure geomorphology are cast in terms of chapters on form, process, materials, and methods analysis. The applied chapters concentrate on environmental hazards and resources, and their management.

  12. A case of recurrent autoimmune hemolytic anemia during remission associated with acute pure red cell aplasia and hemophagocytic syndrome due to human parvovirus B19 infection successfully treated by steroid pulse therapy with a review of the literature.

    PubMed

    Sekiguchi, Yasunobu; Shimada, Asami; Imai, Hidenori; Wakabayashi, Mutsumi; Sugimoto, Keiji; Nakamura, Noriko; Sawada, Tomohiro; Komatsu, Norio; Noguchi, Masaaki

    2014-01-01

    The patient was a 47-year-old man diagnosed as having autoimmune hemolytic anemia (AIHA) in April 2011. He also had a congenital chromosomal abnormality, a balanced translocation. Treatment with prednisolone (PSL) 60 mg/day resulted in resolution of the AIHA, and the treatment was completed in November 2011. While the patient no longer had anemia, the direct and indirect Coombs tests remained positive. In May 2013, he developed recurrent AIHA associated with acute pure red cell aplasia (PRCA) and hemophagocytic syndrome (HPS) caused by human parvovirus B19 (HPV B19) infection. Tests for anti-erythropoietin and anti-erythropoietin receptor antibodies were positive. Steroid pulse therapy resulted in resolution of the AIHA, PRCA, as well as HPS. The serum test for anti-erythropoietin antibodies also became negative after the treatment. However, although the serum was positive for anti-HPV B19 IgG antibodies, the patient continued to have a low CD4 lymphocyte count (CD4, <300/μL) and persistent HPV B19 infection (HPV B19 DNA remained positive), suggesting the risk of recurrence and bone marrow failure.

  13. Production of pure metals

    NASA Technical Reports Server (NTRS)

    Philipp, W. H.; Marsik, S. J.; May, C. E. (Inventor)

    1974-01-01

    A process for depositing elements by irradiating liquids is reported. Ultra pure elements are precipitated from aqueous solutions or suspensions of compounds. A solution of a salt of a metal to be prepared is irradiated, and the insoluble reaction product settles out. Some chemical compounds may also be prepared in this manner.

  14. Dahlbeck and Pure Ontology

    ERIC Educational Resources Information Center

    Mackenzie, Jim

    2016-01-01

    This article responds to Johan Dahlbeck's "Towards a pure ontology: Children's bodies and morality" ["Educational Philosophy and Theory," vol. 46 (1), 2014, pp. 8-23 (EJ1026561)]. His arguments from Nietzsche and Spinoza do not carry the weight he supposes, and the conclusions he draws from them about pedagogy would be…

  15. Dark fermentation on biohydrogen production: Pure culture.

    PubMed

    Lee, Duu-Jong; Show, Kuan-Yeow; Su, Ay

    2011-09-01

    Biohydrogen is regarded as an attractive future clean energy carrier due to its high energy content and environmental-friendly conversion. While biohydrogen production is still in the early stage of development, there have been a variety of laboratory- and pilot-scale systems developed with promising potential. This work presents a review of literature reports on the pure hydrogen-producers under anaerobic environment. Challenges and perspective of biohydrogen production with pure cultures are also outlined.

  16. Purely Cortical Anaplastic Ependymoma

    PubMed Central

    Romero, Flávio Ramalho; Zanini, Marco Antônio; Ducati, Luis Gustavo; Vital, Roberto Bezerra; de Lima Neto, Newton Moreira; Gabarra, Roberto Colichio

    2012-01-01

    Ependymomas are glial tumors derived from ependymal cells lining the ventricles and the central canal of the spinal cord. It may occur outside the ventricular structures, representing the extraventicular form, or without any relationship of ventricular system, called ectopic ependymona. Less than fifteen cases of ectopic ependymomas were reported and less than five were anaplastic. We report a rare case of pure cortical ectopic anaplastic ependymoma. PMID:23119204

  17. Purely cortical anaplastic ependymoma.

    PubMed

    Romero, Flávio Ramalho; Zanini, Marco Antônio; Ducati, Luis Gustavo; Vital, Roberto Bezerra; de Lima Neto, Newton Moreira; Gabarra, Roberto Colichio

    2012-01-01

    Ependymomas are glial tumors derived from ependymal cells lining the ventricles and the central canal of the spinal cord. It may occur outside the ventricular structures, representing the extraventicular form, or without any relationship of ventricular system, called ectopic ependymona. Less than fifteen cases of ectopic ependymomas were reported and less than five were anaplastic. We report a rare case of pure cortical ectopic anaplastic ependymoma.

  18. Pure Lovelock Kasner metrics

    NASA Astrophysics Data System (ADS)

    Camanho, Xián O.; Dadhich, Naresh; Molina, Alfred

    2015-09-01

    We study pure Lovelock vacuum and perfect fluid equations for Kasner-type metrics. These equations correspond to a single Nth order Lovelock term in the action in d=2N+1,2N+2 dimensions, and they capture the relevant gravitational dynamics when aproaching the big-bang singularity within the Lovelock family of theories. Pure Lovelock gravity also bears out the general feature that vacuum in the critical odd dimension, d=2N+1, is kinematic, i.e. we may define an analogue Lovelock-Riemann tensor that vanishes in vacuum for d=2N+1, yet the Riemann curvature is non-zero. We completely classify isotropic and vacuum Kasner metrics for this class of theories in several isotropy types. The different families can be characterized by means of certain higher order 4th rank tensors. We also analyze in detail the space of vacuum solutions for five- and six dimensional pure Gauss-Bonnet theory. It possesses an interesting and illuminating geometric structure and symmetries that carry over to the general case. We also comment on a closely related family of exponential solutions and on the possibility of solutions with complex Kasner exponents. We show that the latter imply the existence of closed timelike curves in the geometry.

  19. 7 CFR 917.8 - Pure grower or pure producer.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 917.8 Pure grower or pure producer. (a) For peaches,...

  20. 7 CFR 917.8 - Pure grower or pure producer.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 917.8 Pure grower or pure producer. (a) For peaches,...

  1. Viscosity of pure hydrocarbons

    SciTech Connect

    Knapstad, B.; Skjolsvik, P.A.; Oye, H.A.

    1989-01-01

    Accurate viscosity measurements have been performed on eight pure hydrocarbons at atmospheric pressure in the temperature range 20-150/sup 0/C, or up to approximately 20/sup 0/C below the boiling point of the hydrocarbon, by use of an absolute oscillating viscometer. The hydrocarbons are cyclohexane and benzene and the n-alkanes of hexane, heptane, octane, decane, dodecane, and tetradecane. The viscosities are described with a modified Arrhenius equation, and the deviation in fit is 0.12% or less. The accuracy is estimated to be 0.33-0.56%. The lowest viscosities are assumed to have the highest deviation. Literature data reported by Dymond and Young normally fit our viscosities within our estimated accuracy. Other literature viscosities tend to be higher than our results, especially for the n-alkanes.

  2. Effectiveness of enhanced communication therapy in the first four months after stroke for aphasia and dysarthria: a randomised controlled trial

    PubMed Central

    Hesketh, Anne; Patchick, Emma; Young, Alys; Davies, Linda; Vail, Andy; Long, Andrew F; Watkins, Caroline; Wilkinson, Mo; Pearl, Gill; Ralph, Matthew A Lambon; Tyrrell, Pippa

    2012-01-01

    Objective To assess the effectiveness of enhanced communication therapy in the first four months after stroke compared with an attention control (unstructured social contact). Design Externally randomised, pragmatic, parallel, superiority trial with blinded outcome assessment. Setting Twelve UK hospital and community stroke services. Participants 170 adults (mean age 70 years) randomised within two weeks of admission to hospital with stroke (December 2006 to January 2010) whom speech and language therapists deemed eligible, and 135 carers. Interventions Enhanced, agreed best practice, communication therapy specific to aphasia or dysarthria, offered by speech and language therapists according to participants’ needs for up to four months, with continuity from hospital to community. Comparison was with similarly resourced social contact (without communication therapy) from employed visitors. Outcome measures Primary outcome was blinded, functional communicative ability at six months on the Therapy Outcome Measure (TOM) activity subscale. Secondary outcomes (unblinded, six months): participants’ perceptions on the Communication Outcomes After Stroke scale (COAST); carers’ perceptions of participants from part of the Carer COAST; carers’ wellbeing on Carers of Older People in Europe Index and quality of life items from Carer COAST; and serious adverse events. Results Therapist and visitor contact both had good uptake from service users. An average 22 contacts (intervention or control) over 13 weeks were accepted by users. Impairment focused therapy was the approach most often used by the speech and language therapists. Visitors most often provided general conversation. In total, 81/85 of the intervention group and 72/85 of the control group completed the primary outcome measure. Both groups improved on the TOM activity subscale. The estimated six months group difference was not statistically significant, with 0.25 (95% CI –0.19 to 0.69) points in favour of

  3. Pure neuritic leprosy: Current status and relevance.

    PubMed

    Rao, P Narasimha; Suneetha, Sujai

    2016-01-01

    Pure neuritic leprosy has always been an enigma due to its clinical and management ambiguities. Although only the Indian Association of Leprologist's classification recognizes 'pure neuritic leprosy' as a distinct sub group of leprosy, cases nonetheless are reported from various countries of Asia, Africa, South America and Europe, indicating its global relevance. It is important to maintain pure neuritic leprosy as a subgroup as it constitutes a good percentage of leprosy cases reported from India, which contributes to more than half of global leprosy numbers. Unfortunately, a high proportion of these patients present with Grade 2 disability at the time of initial reporting itself due to the early nerve involvement. Although skin lesions are absent by definition, when skin biopsies were performed from the skin along the distribution of the affected nerve, a proportion of patients demonstrated leprosy pathology, revealing sub-clinical skin involvement. In addition on follow-up, skin lesions are noted to develop in up to 20% of pure neuritic leprosy cases, indicating its progression to manifest cutaneous disease. Over the decades, the confirmation of diagnosis of pure neuritic leprosy has been subjective, however, with the arrival and use of high-resolution ultrasonography (HRUS) for nerve imaging, we have a tool not only to objectively measure and record the nerve thickening but also to assess the morphological alterations in the nerve including echo texture, fascicular pattern and vascularity. Management of pure neuritic leprosy requires multidrug therapy along with appropriate dose of systemic corticosteroids, for both acute and silent neuritis. Measures for pain relief, self-care of limbs and physiotherapy are important to prevent as well as manage disabilities in this group of patients. PMID:27088926

  4. Characterizing commercial pureed foods: sensory, nutritional, and textural analysis.

    PubMed

    Ettinger, Laurel; Keller, Heather H; Duizer, Lisa M

    2014-01-01

    Dysphagia (swallowing impairment) is a common consequence of stroke and degenerative diseases such as Parkinson's and Alzheimer's. Limited research is available on pureed foods, specifically the qualities of commercial products. Because research has linked pureed foods, specifically in-house pureed products, to malnutrition due to inferior sensory and nutritional qualities, commercial purees also need to be investigated. Proprietary research on sensory attributes of commercial foods is available; however direct comparisons of commercial pureed foods have never been reported. Descriptive sensory analysis as well as nutritional and texture analysis of commercially pureed prepared products was performed using a trained descriptive analysis panel. The pureed foods tested included four brands of carrots, of turkey, and two of bread. Each commercial puree was analyzed for fat (Soxhlet), protein (Dumas), carbohydrate (proximate analysis), fiber (total fiber), and sodium content (Quantab titrator strips). The purees were also texturally compared with a line spread test and a back extrusion test. Differences were found in the purees for sensory attributes as well as nutritional and textural properties. Findings suggest that implementation of standards is required to reduce variability between products, specifically regarding the textural components of the products. This would ensure all commercial products available in Canada meet standards established as being considered safe for swallowing.

  5. Inherited peripheral neuropathies due to mitochondrial disorders.

    PubMed

    Cassereau, J; Codron, P; Funalot, B

    2014-05-01

    Mitochondrial disorders (MIDs) are frequently responsible for neuropathies with variable severity. Mitochondrial diseases causing peripheral neuropathies (PNP) may be due to mutations of mitochondrial DNA (mtDNA), as is the case in MERRF and MELAS syndromes, or to mutations of nuclear genes. Secondary abnormalities of mtDNA (such as multiple deletions of muscle mtDNA) may result from mitochondrial disorders due to mutations in nuclear genes involved in mtDNA maintenance. This is the case in several syndromes caused by impaired mtDNA maintenance, such as Sensory Ataxic Neuropathy, Dysarthria and Ophthalmoplegia (SANDO) due to recessive mutations in the POLG gene, which encodes the catalytic subunit of mtDNA polymerase (DNA polymerase gamma), or Mitochondrial Neuro-Gastro-Intestinal Encephalomyopathy (MNGIE), due to recessive mutations in the TYMP gene, which encodes thymidine phosphorylase. The last years have seen a growing list of evidence demonstrating that mitochondrial bioenergetics and dynamics might be dysfunctional in axonal Charcot-Marie-Tooth disease (CMT2), and these mechanisms might present a common link between dissimilar CMT2-causing genes.

  6. "Pure" cutaneous histiocytosis-X.

    PubMed

    Wolfson, S L; Botero, F; Hurwitz, S; Pearson, H A

    1981-11-15

    The case histories of two young children who experienced skin rashes involving various areas of the body are reported. The diagnosis of pure cutaneous histiocytosis-X was established after extensive studies revealed no other organ involvement. The patients were treated with oral corticosteroids. Currently, both children are in good health, show no evidence of disease, and have been followed over a four-to-five-year period. Therapy with corticosteroids may not be indicated with pure cutaneous histiocytosis-X unless there is evidence of extracutaneous dissemination or rapid progression of the disease.

  7. Graphical calculus for Gaussian pure states

    SciTech Connect

    Menicucci, Nicolas C.; Flammia, Steven T.; Loock, Peter van

    2011-04-15

    We provide a unified graphical calculus for all Gaussian pure states, including graph transformation rules for all local and semilocal Gaussian unitary operations, as well as local quadrature measurements. We then use this graphical calculus to analyze continuous-variable (CV) cluster states, the essential resource for one-way quantum computing with CV systems. Current graphical approaches to CV cluster states are only valid in the unphysical limit of infinite squeezing, and the associated graph transformation rules only apply when the initial and final states are of this form. Our formalism applies to all Gaussian pure states and subsumes these rules in a natural way. In addition, the term 'CV graph state' currently has several inequivalent definitions in use. Using this formalism we provide a single unifying definition that encompasses all of them. We provide many examples of how the formalism may be used in the context of CV cluster states: defining the 'closest' CV cluster state to a given Gaussian pure state and quantifying the error in the approximation due to finite squeezing; analyzing the optimality of certain methods of generating CV cluster states; drawing connections between this graphical formalism and bosonic Hamiltonians with Gaussian ground states, including those useful for CV one-way quantum computing; and deriving a graphical measure of bipartite entanglement for certain classes of CV cluster states. We mention other possible applications of this formalism and conclude with a brief note on fault tolerance in CV one-way quantum computing.

  8. Production of substantially pure fructose

    DOEpatents

    Hatcher, Herbert J.; Gallian, John J.; Leeper, Stephen A.

    1990-01-01

    A process is disclosed for the production of substantially pure fructose from sucrose-containing substrates. The process comprises converting the sucrose to levan and glucose, purifying the levan by membrane technology, hydrolyzing the levan to form fructose monomers, and recovering the fructose.

  9. Effect of humidity on fretting wear of several pure metals

    NASA Technical Reports Server (NTRS)

    Goto, H.; Buckley, D. H.

    1984-01-01

    Fretting wear experiments with several pure metals were conducted in air at various relative humidity levels. The materials used were iron, aluminum, copper, silver, chromium, titanium, and nickel. Each pure metal had a maximum fretting wear volume at a specific humidity level RH sub max that was not dependent on mechanical factors such as contact load, fretting amplitude, and frequency in the ranges studied. The weight loss due to fretting wear at RH sub max for each pure metal decreased with increasing heat of oxygen adsorption on the metal, indicating that adhesive wear dominated at RH sub max.

  10. Canonical Thermal Pure Quantum State

    NASA Astrophysics Data System (ADS)

    Sugiura, Sho; Shimizu, Akira

    2013-07-01

    A thermal equilibrium state of a quantum many-body system can be represented by a typical pure state, which we call a thermal pure quantum (TPQ) state. We construct the canonical TPQ state, which corresponds to the canonical ensemble of the conventional statistical mechanics. It is related to the microcanonical TPQ state, which corresponds to the microcanonical ensemble, by simple analytic transformations. Both TPQ states give identical thermodynamic results, if both ensembles do, in the thermodynamic limit. The TPQ states corresponding to other ensembles can also be constructed. We have thus established the TPQ formulation of statistical mechanics, according to which all quantities of statistical-mechanical interest are obtained from a single realization of any TPQ state. We also show that it has great advantages in practical applications. As an illustration, we study the spin-1/2 kagome Heisenberg antiferromagnet.

  11. The neuroanatomy of pure apraxia of speech in stroke

    PubMed Central

    Graff-Radford, Jonathan; Jones, David T.; Strand, Edythe A.; Rabinstein, Alejandro A.; Duffy, Joseph R.; Josephs, Keith A.

    2014-01-01

    The left insula or Broca’s area have been proposed as the neuroanatomical correlate for apraxia of speech (AOS) based on studies of patients with both AOS and aphasia due to stroke. Studies of neurodegenerative AOS suggest the premotor area and the supplementary motor areas as the anatomical correlates. The study objective was to determine the common infarction area in patients with pure AOS due to stroke. Patients with AOS and no or equivocal aphasia due to ischemic stroke were identified through a pre-existing database. Seven subjects were identified. Five had pure AOS, and two had equivocal aphasia. MRI lesion analysis revealed maximal overlap spanning the left premotor and motor cortices. While both neurodegenerative AOS and stroke induced pure AOS involve the premotor cortex, further studies are needed to establish whether stroke-induced AOS and neurodegenerative AOS share a common anatomic substrate. PMID:24556336

  12. The neuroanatomy of pure apraxia of speech in stroke.

    PubMed

    Graff-Radford, Jonathan; Jones, David T; Strand, Edythe A; Rabinstein, Alejandro A; Duffy, Joseph R; Josephs, Keith A

    2014-02-01

    The left insula or Broca's area have been proposed as the neuroanatomical correlate for apraxia of speech (AOS) based on studies of patients with both AOS and aphasia due to stroke. Studies of neurodegenerative AOS suggest the premotor area and the supplementary motor areas as the anatomical correlates. The study objective was to determine the common infarction area in patients with pure AOS due to stroke. Patients with AOS and no or equivocal aphasia due to ischemic stroke were identified through a pre-existing database. Seven subjects were identified. Five had pure AOS, and two had equivocal aphasia. MRI lesion analysis revealed maximal overlap spanning the left premotor and motor cortices. While both neurodegenerative AOS and stroke induced pure AOS involve the premotor cortex, further studies are needed to establish whether stroke-induced AOS and neurodegenerative AOS share a common anatomic substrate. PMID:24556336

  13. Pure gonadal dysgenesis (46 XX type) with a familial pattern.

    PubMed

    Kohmanaee, Shahin; Dalili, Setila; Rad, Afagh Hassanzadeh

    2015-01-01

    46, XX gonadal dysgenesis without the phenotype of Turner's syndrome is described as "pure". Although, previous investigations obtained that commonly gonadal dysgenesis did not cause breast development as a result of low levels of circulating estradiol. However, in this study, we aimed to report a familial pure gonadal dysgenesis with and without normal secondary sexual characteristics. In this study, we reported three siblings with pure gonadal dysgenesis with and without normal secondary sexual characteristics. The elder two sisters had a normal female phenotype and the youngest had amenorrhea with no breast development (B1) and pubic hair. In addition, it seems that the absence of pubic hair occurred due to delayed constitutional puberty. According to results, it seems that clinicians should consider different presentations for pure gonadal dysgenesis with familial pattern.

  14. Synthesis of Enantiomerically Pure Anthracyclinones

    NASA Astrophysics Data System (ADS)

    Achmatowicz, Osman; Szechner, Barbara

    The anthracycline antibiotics are among the most important clinical drugs used in the treatment of human cancer. The search for new agents with improved therapeutic efficacy and reduced cardiotoxicity stimulated considerable efforts in the synthesis of new analogues. Since the biological activity of anthracyclines depends on their natural absolute configuration, various strategies for the synthesis of enantiomerically pure anthracyclinones (aglycones) have been developed. They comprise: resolution of racemic intermediate, incorporation of a chiral fragment derived from natural and non-natural chiral pools, asymmetric synthesis with the use of a chiral auxiliary or a chiral reagent, and enantioselective catalysis. Synthetic advances towards enantiopure anthracyclinones reported over the last 17 years are reviewed.

  15. Production of substantially pure fructose

    SciTech Connect

    Hatcher, H.J.; Gallian, J.J.; Leeper, S.A.

    1990-05-22

    This patent describes a process for the production of a substantially pure product containing greater than 60% fructose. It comprises: combining a sucrose-containing substrate with effective amounts of a levansucrase enzyme preparation to form levan and glucose; purifying the levan by at least one of the following purification methods: ultrafiltration, diafiltration, hyperfiltration, reverse osmosis, liquid--liquid partition, solvent extraction, chromatography, and precipitation; hydrolyzing the levan to form fructose substantially free of glucose and sucrose; and recovering the fructose by at least one of the following recovery methods: hyperfiltration, reverse osmosis, evaporation, drying, crystallization, and chromatography.

  16. Nanoporous Au: an unsupported pure gold catalyst?

    SciTech Connect

    Wittstock, A; Neumann, B; Schaefer, A; Dumbuya, K; Kuebel, C; Biener, M; Zielasek, V; Steinrueck, H; Gottfried, M; Biener, J; Hamza, A; B?umer, M

    2008-09-04

    The unique properties of gold especially in low temperature CO oxidation have been ascribed to a combination of various effects. In particular, particle sizes below a few nm and specific particle-support interactions have been shown to play important roles. On the contrary, recent reports revealed that monolithic nanoporous gold (npAu) prepared by leaching a less noble metal, such as Ag, out of the corresponding alloy can also exhibit remarkably high catalytic activity for CO oxidation, even though no support is present. Therefore, it was claimed to be a pure and unsupported gold catalyst. We investigated npAu with respect to its morphology, surface composition and catalytic properties. In particular, we studied the reaction kinetics for low temperature CO oxidation in detail taking mass transport limitation due to the porous structure of the material into account. Our results reveal that Ag, even if removed almost completely from the bulk, segregates to the surface resulting in surface concentrations of up to 10 at%. Our data suggest that this Ag plays a significant role in activation of molecular oxygen. Therefore, npAu should be considered as a bimetallic catalyst rather than a pure Au catalyst.

  17. Cosmic Shear - with ACS Pure Parallel Observations

    NASA Astrophysics Data System (ADS)

    Ratnatunga, Kavan

    2002-07-01

    The ACS, with greater sensitivity and sky coverage, will extend our ability to measure the weak gravitational lensing of galaxy images caused by the large scale distribution of dark matter. We propose to use the ACS in pure parallel {non- proprietary} mode, following the guidelines of the ACS Default Pure Parallel Program. Using the HST Medium Deep Survey WFPC2 database we have measured cosmic shear at arc-min angular scales. The MDS image parameters, in particular the galaxy orientations and axis ratios, are such that any residual corrections due to errors in the PSF or jitter are much smaller than the measured signal. This situation is in stark contrast with ground-based observations. We have also developed a statistical analysis procedure to derive unbiased estimates of cosmic shear from a large number of fields, each of which has a very small number of galaxies. We have therefore set the stage for measurements with the ACS at fainter apparent magnitudes and smaller, 10 arc-second scales corresponding to larger cosmological distances. We will adapt existing MDS WFPC2 maximum likelihood galaxy image analysis algorithms to work with the ACS. The analysis would also yield an online database similar to that in archive.stsci.edu/mds/

  18. Anomalous rectification in a purely electronic memristor

    NASA Astrophysics Data System (ADS)

    Wang, Jingrui; Pan, Ruobing; Cao, Hongtao; Wang, Yang; Liang, Lingyan; Zhang, Hongliang; Gao, Junhua; Zhuge, Fei

    2016-10-01

    An anomalous rectification was observed in a purely electronic memristive device Ti/ZnO/Pt. It could be due to (1) an Ohmic or quasi-Ohmic contact at the ZnO/Pt interface and (2) a Schottky contact at the Ti/ZnO interface. The Ohmic contact originates from the reduction of ZnO occurring in the whole film instead of only at the Ti/ZnO interface. The Schottky contact may come from moisture adsorbed in the nanoporous ZnO. The conduction in the electroformed device is controlled by the carrier trapping/detrapping of the trap sites, inducing a poor rectification and high nonlinearity. Furthermore, a complementary resistive switching was achieved.

  19. Preparation and accurate measurement of pure ozone.

    PubMed

    Janssen, Christof; Simone, Daniela; Guinet, Mickaël

    2011-03-01

    Preparation of high purity ozone as well as precise and accurate measurement of its pressure are metrological requirements that are difficult to meet due to ozone decomposition occurring in pressure sensors. The most stable and precise transducer heads are heated and, therefore, prone to accelerated ozone decomposition, limiting measurement accuracy and compromising purity. Here, we describe a vacuum system and a method for ozone production, suitable to accurately determine the pressure of pure ozone by avoiding the problem of decomposition. We use an inert gas in a particularly designed buffer volume and can thus achieve high measurement accuracy and negligible degradation of ozone with purities of 99.8% or better. The high degree of purity is ensured by comprehensive compositional analyses of ozone samples. The method may also be applied to other reactive gases. PMID:21456766

  20. 76 FR 69284 - Pure Magnesium From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ... COMMISSION Pure Magnesium From China Determination On the basis of the record \\1\\ developed in the subject... order on pure magnesium from China would be likely to lead to continuation or recurrence of material... USITC Publication 4274 (October 2011), entitled Pure Magnesium from China: Investigation No....

  1. Clinical study of 222 patients with pure motor stroke.

    PubMed

    Arboix, A; Padilla, I; Massons, J; García-Eroles, L; Comes, E; Targa, C

    2001-08-01

    The objective was to assess the frequency of pure motor stroke caused by different stroke subtypes and to compare demographic, clinical, neuroimaging, and outcome data of pure motor stroke with those of patients with other lacunar stroke as well as with those of patients with non-lacunar stroke. Data from 2000 patients with acute stroke (n=1761) or transient ischaemic attack (n=239) admitted consecutively to the department of neurology of an acute care 350 bed teaching hospital were prospectively collected in the Sagrat Cor Hospital of Barcelona stroke registry over a 10 year period. For the purpose of the study 222 (12.7%) patients with pure motor stroke were selected. The other study groups included 218 (12.3%) patients with other lacunar strokes and 1321 (75%) patients with non-lacunar stroke. In relation to stroke subtype, lacunar infarcts were found in 189 (85%) patients, whereas ischaemic lacunar syndromes not due to lacunar infarcts occurred in 23 (10.4%) patients (atherothrombotic stroke in 12, cardioembolic stroke in seven, infarction of undetermined origin in three, and infarction of unusual aetiology in one) and haemorrhagic lacunar syndromes in 10 (4.5%). Patients with pure motor stroke showed a better outcome than patients with non-lacunar stroke with a significantly lower number of complications and in hospital mortality rate, shorter duration of hospital stay, and a higher number of symptom free patients at hospital discharge. After multivariate analysis, hypertension, diabetes, obesity, hyperlipidaemia, non-sudden stroke onset, internal capsule involvement, and pons topography seemed to be independent factors of pure motor stroke in patients with acute stroke. In conclusion, about one of every 10 patients with acute stroke had a pure motor stroke. Pure motor stroke was caused by a lacunar infarct in 85% of patients and by other stroke subtypes in 15%. Several clinical features are more frequent in patients with pure motor stroke than in patients

  2. Mixtures of maximally entangled pure states

    NASA Astrophysics Data System (ADS)

    Flores, M. M.; Galapon, E. A.

    2016-09-01

    We study the conditions when mixtures of maximally entangled pure states remain entangled. We found that the resulting mixed state remains entangled when the number of entangled pure states to be mixed is less than or equal to the dimension of the pure states. For the latter case of mixing a number of pure states equal to their dimension, we found that the mixed state is entangled provided that the entangled pure states to be mixed are not equally weighted. We also found that one can restrict the set of pure states that one can mix from in order to ensure that the resulting mixed state is genuinely entangled. Also, we demonstrate how these results could be applied as a way to detect entanglement in mixtures of the entangled pure states with noise.

  3. Isomerically Pure Tetramethylrhodamine Voltage Reporters.

    PubMed

    Deal, Parker E; Kulkarni, Rishikesh U; Al-Abdullatif, Sarah H; Miller, Evan W

    2016-07-27

    We present the design, synthesis, and application of a new family of fluorescent voltage indicators based on isomerically pure tetramethylrhodamines. These new Rhodamine Voltage Reporters, or RhoVRs, use photoinduced electron transfer (PeT) as a trigger for voltage sensing, display excitation and emission profiles in the green to orange region of the visible spectrum, demonstrate high sensitivity to membrane potential changes (up to 47% ΔF/F per 100 mV), and employ a tertiary amide derived from sarcosine, which aids in membrane localization and simultaneously simplifies the synthetic route to the voltage sensors. The most sensitive of the RhoVR dyes, RhoVR 1, features a methoxy-substituted diethylaniline donor and phenylenevinylene molecular wire at the 5'-position of the rhodamine aryl ring, exhibits the highest voltage sensitivity to date for red-shifted PeT-based voltage sensors, and is compatible with simultaneous imaging alongside green fluorescent protein-based indicators. The discoveries that sarcosine-based tertiary amides in the context of molecular-wire voltage indicators prevent dye internalization and 5'-substituted voltage indicators exhibit improved voltage sensitivity should be broadly applicable to other types of PeT-based voltage-sensitive fluorophores. PMID:27428174

  4. Bringing Planctomycetes into pure culture

    PubMed Central

    Lage, Olga M.; Bondoso, Joana

    2012-01-01

    Planctomycetes have been known since the description of Planctomyces bekefii by Gimesi at the beginning of the twentieth century (1924), although the first axenic cultures were only obtained in the 1970s. Since then, 11 genera with 14 species have been validly named and five candidatus genera belonging to the anaerobic ammonium oxidation, anammox bacteria have also been discovered. However, Planctomycetes diversity is much broader than these numbers indicate, as shown by environmental molecular studies. In recent years, the authors have attempted to isolate and cultivate additional strains of Planctomycetes. This paper provides a summary of the isolation work that was carried out to obtain in pure culture Planctomycetes from several environmental sources. The following strains of planctomycetes have been successfully isolated: two freshwater strains from the sediments of an aquarium, which were described as a new genus and species, Aquisphaera giovannonii; several Rhodopirellula strains from the sediments of a water treatment recycling tank of a marine fish farm; and more than 140 planctomycetes from the biofilm community of macroalgae. This collection comprises several novel taxa that are being characterized and described. Improvements in the isolation methodology were made in order to optimize and enlarge the number of Planctomycetes isolated from the macroalgae. The existence of an intimate and an important relationship between planctomycetes and macroalgae reported before by molecular studies is therefore supported by culture-dependent methods. PMID:23335915

  5. Social cognition in "pure" delusional disorder.

    PubMed

    Bömmer, Isabel; Brüne, Martin

    2006-09-01

    Introduction. Delusional disorders are characterised by monothematic, "encapsulated" and incorrigible false beliefs and misinterpretations of social signals. Due to the rarity of cases with "pure" delusional disorder (DD) in clinical settings most studies of social cognition in delusional patients have focused on patients with paranoid schizophrenia. In the present study we sought to examine emotion recognition, theory of mind abilities, and pragmatic language comprehension in patients with delusional disorder. Methods. Social cognition was assessed in 21 patients recruited over a 3-year period who were diagnosed with delusional disorder, paranoid, erotomanic, or jealous type. In addition to an emotion recognition and theory of mind test battery, we included a novel German Proverb Test, which has been found indicative of subtle theory of mind deficits in schizophrenic patients. Executive functioning was assessed using the Wisconsin Card Sorting Test (WCST). Psychopathology was measured using the Positive and Negative Symptoms Scale (PANSS). Patients' task performance was compared to a group of 22 healthy control persons paralleled for verbal intelligence, education, and age. Results. Patients with DD made significantly more perseverative errors in the WCST, they performed more poorly on the theory of mind tasks and the proverb test, but were unimpaired in basic emotion recognition abilities relative to controls. When executive functioning was co-varied out, the group differences in theory of mind disappeared, whereas the greater propensity of patients with DD to interpret proverbs literally remained significant. Conclusions. In "pure" DD the basic social cognitive abilities appear to be preserved. Difficulties in metaphorical speech comprehension and executive functioning could, however, indicate more subtle social cognitive deficits in these patients. PMID:17354084

  6. Method of preparing pure fluorine gas

    DOEpatents

    Asprey, Larned B.

    1976-01-01

    A simple, inexpensive system for purifying and storing pure fluorine is described. The method utilizes alkali metal-nickel fluorides to absorb tank fluorine by forming nickel complex salts and leaving the gaseous impurities which are pumped away. The complex nickel fluoride is then heated to evolve back pure gaseous fluorine.

  7. Foaming of mixtures of pure hydrocarbons

    NASA Technical Reports Server (NTRS)

    Robinson, J. V.; Woods, W. W.

    1950-01-01

    Mixtures of pure liquid hydrocarbons are capable of foaming. Nine hydrocarbons were mixed in pairs, in all possible combinations, and four proportions of each combination. These mixtures were sealed in glass tubes, and the foaming was tested by shaking. Mixtures of aliphatic with other aliphatic hydrocarbons, or of alkyl benzenes with other alkyl benzenes, did not foam. Mixtures of aliphatic hydrocarbons with alkyl benzenes did foam. The proportions of the mixtures greatly affected the foaming, the maximum foaming of 12 of 20 pairs being at the composition 20 percent aliphatic hydrocarbon, 80 percent alkyl benzene. Six seconds was the maximum foam lifetime of any of these mixtures. Aeroshell 120 lubricating oil was fractionated into 52 fractions and a residue by extraction with acetone in a fractionating extractor. The index of refraction, foam lifetime, color, and viscosity of these fractions were measured. Low viscosity and high index fractions were extracted first. The viscosity of the fractions extracted rose and the index decreased as fractionation proceeded. Foam lifetimes and color were lowest in the middle fractions. Significance is attached to the observation that none of the foam lifetimes of the fractions or residue is as high as the foam lifetime of the original Aeroshell, indicating that the foaming is not due to a particular foaming constituent, but rather to the entire mixture.

  8. Lateral Stress Measurements in Pure Tungsten during Shock Loading

    SciTech Connect

    Millett, J. C. F.; Gray, G. T. III; Bourne, N. K.

    2006-07-28

    Longitudinal and lateral stresses during the shock loading of pure tungsten have been measured using manganin stress gauges. The Hugoniot has been compared to the previous work of others and shown to be in close agreement. Lateral stresses have been shown to increase behind the shock front, implying that the shear strength decreases. Whilst this is similar to results in tantalum, comparison with recovery experiments in the literature suggests that this may be due in part to a brittle failure process.

  9. Clinical study of 222 patients with pure motor stroke

    PubMed Central

    Arboix, A; Padilla, I; Massons, J; Garcia-Eroles, L; Comes, E; Targa, C

    2001-01-01

    The objective was to assess the frequency of pure motor stroke caused by different stroke subtypes and to compare demographic, clinical, neuroimaging, and outcome data of pure motor stroke with those of patients with other lacunar stroke as well as with those of patients with non-lacunar stroke.
Data from 2000 patients with acute stroke (n=1761) or transient ischaemic attack (n=239) admitted consecutively to the department of neurology of an acute care 350 bed teaching hospital were prospectively collected in the Sagrat Cor Hospital of Barcelona stroke registry over a 10 year period. For the purpose of the study 222 (12.7%) patients with pure motor stroke were selected. The other study groups included 218 (12.3%) patients with other lacunar strokes and 1321 (75%) patients with non-lacunar stroke.
In relation to stroke subtype, lacunar infarcts were found in 189 (85%) patients, whereas ischaemic lacunar syndromes not due to lacunar infarcts occurred in 23 (10.4%) patients (atherothrombotic stroke in 12, cardioembolic stroke in seven, infarction of undetermined origin in three, and infarction of unusual aetiology in one) and haemorrhagic lacunar syndromes in 10 (4.5%). Patients with pure motor stroke showed a better outcome than patients with non-lacunar stroke with a significantly lower number of complications and in hospital mortality rate, shorter duration of hospital stay, and a higher number of symptom free patients at hospital discharge. After multivariate analysis, hypertension, diabetes, obesity, hyperlipidaemia, non-sudden stroke onset, internal capsule involvement, and pons topography seemed to be independent factors of pure motor stroke in patients with acute stroke.
In conclusion, about one of every 10 patients with acute stroke had a pure motor stroke. Pure motor stroke was caused by a lacunar infarct in 85% of patients and by other stroke subtypes in 15%. Several clinical features are more frequent in patients with pure motor stroke than in

  10. In vitro degradation of pure Mg in response to glucose

    PubMed Central

    Zeng, Rong-Chang; Li, Xiao-Ting; Li, Shuo-Qi; Zhang, Fen; Han, En-Hou

    2015-01-01

    Magnesium and its alloys are promising biodegradable biomaterials but are still challenging to be used in person with high levels of blood glucose or diabetes. To date, the influence of glucose on magnesium degradation has not yet been elucidated, this issue requires more attention. Herein, we present pure Mg exhibiting different corrosion responses to saline and Hank’s solutions with different glucose contents, and the degradation mechanism of pure Mg in the saline solution with glucose in comparison with mannitol as a control. On one hand, the corrosion rate of pure Mg increases with the glucose concentration in saline solutions. Glucose rapidly transforms into gluconic acid, which attacks the oxides of the metal and decreases the pH of the solution; it also promotes the absorption of chloride ions on the Mg surface and consequently accelerates corrosion. On the other hand, better corrosion resistance is obtained with increasing glucose content in Hank’s solution due to the fact that glucose coordinates Ca2+ ions in Hank’s solution and thus improves the formation of Ca-P compounds on the pure Mg surface. This finding will open up new avenues for research on the biodegradation of bio-Mg materials in general, which could yield many new and interesting results. PMID:26264413

  11. In vitro degradation of pure Mg in response to glucose

    NASA Astrophysics Data System (ADS)

    Zeng, Rong-Chang; Li, Xiao-Ting; Li, Shuo-Qi; Zhang, Fen; Han, En-Hou

    2015-08-01

    Magnesium and its alloys are promising biodegradable biomaterials but are still challenging to be used in person with high levels of blood glucose or diabetes. To date, the influence of glucose on magnesium degradation has not yet been elucidated, this issue requires more attention. Herein, we present pure Mg exhibiting different corrosion responses to saline and Hank’s solutions with different glucose contents, and the degradation mechanism of pure Mg in the saline solution with glucose in comparison with mannitol as a control. On one hand, the corrosion rate of pure Mg increases with the glucose concentration in saline solutions. Glucose rapidly transforms into gluconic acid, which attacks the oxides of the metal and decreases the pH of the solution; it also promotes the absorption of chloride ions on the Mg surface and consequently accelerates corrosion. On the other hand, better corrosion resistance is obtained with increasing glucose content in Hank’s solution due to the fact that glucose coordinates Ca2+ ions in Hank’s solution and thus improves the formation of Ca-P compounds on the pure Mg surface. This finding will open up new avenues for research on the biodegradation of bio-Mg materials in general, which could yield many new and interesting results.

  12. Pure spin current transport in Alq3 by spin pumping

    NASA Astrophysics Data System (ADS)

    Jiang, Shengwei; Wang, Peng; Luan, Zhongzhi; Tao, Xinde; Ding, Haifeng; Wu, Di

    2015-03-01

    The use of organic semiconductors (OSCs) in spintronics has aroused considerable interests, owing to their much longer spin-relaxation times of OSCs than those of inorganic counterparts. The most studied example is the organic spin valve (OSV), in which magnetoresistance (MR) effect is frequently reported. However, studies on pure spin current injection and transport in OSCs are scarce. Recently, the pioneering work by Watanabe et al. demonstrated that pure spin current can be pumped into and propagates in semiconducting polymers. In the present work we extend the study to small molecule OSCs, and demonstrate that pure spin current can be injected into Alq3 from the adjacent magnetic insulator Y3Fe5O12 (YIG) by spin pumping. The pure spin current is detected by inverse spin Hall effect (ISHE) in Pd after propagation through Alq3. From the ISHE voltage VISHE as a function of the Alq3 thickness, the spin diffusion length is determined to be ~ 50 nm and does not depend on temperature. This result indicates the MR decrease as increasing temperature in OSVs is not due to the reduced spin diffusion length.

  13. Quantifying the coherence of pure quantum states

    NASA Astrophysics Data System (ADS)

    Chen, Jianxin; Grogan, Shane; Johnston, Nathaniel; Li, Chi-Kwong; Plosker, Sarah

    2016-10-01

    In recent years, several measures have been proposed for characterizing the coherence of a given quantum state. We derive several results that illuminate how these measures behave when restricted to pure states. Notably, we present an explicit characterization of the closest incoherent state to a given pure state under the trace distance measure of coherence. We then use this result to show that the states maximizing the trace distance of coherence are exactly the maximally coherent states. We define the trace distance of entanglement and show that it coincides with the trace distance of coherence for pure states. Finally, we give an alternate proof to a recent result that the ℓ1 measure of coherence of a pure state is never smaller than its relative entropy of coherence.

  14. Rehabilitation of pure alexia: A review

    PubMed Central

    Starrfelt, Randi; Ólafsdóttir, Rannveig Rós; Arendt, Ida-Marie

    2013-01-01

    Acquired reading problems caused by brain injury (alexia) are common, either as a part of an aphasic syndrome, or as an isolated symptom. In pure alexia, reading is impaired while other language functions, including writing, are spared. Being in many ways a simple syndrome, one would think that pure alexia was an easy target for rehabilitation efforts. We review the literature on rehabilitation of pure alexia from 1990 to the present, and find that patients differ widely on several dimensions, such as alexia severity and associated deficits. Many patients reported to have pure alexia in the reviewed studies, have associated deficits such as agraphia or aphasia and thus do not strictly conform to the diagnosis. Few studies report clear and generalisable effects of training, none report control data, and in many cases the reported findings are not supported by statistics. We can, however, tentatively conclude that Multiple Oral Re-reading techniques may have some effect in mild pure alexia where diminished reading speed is the main problem, while Tacile-Kinesthetic training may improve letter identification in more severe cases of alexia. There is, however, still a great need for well-designed and controlled studies of rehabilitation of pure alexia. PMID:23808895

  15. Engineering arbitrary pure and mixed quantum states

    SciTech Connect

    Pechen, Alexander

    2011-10-15

    Controlled manipulation by atomic- and molecular-scale quantum systems has attracted a lot of research attention in recent years. A fundamental problem is to provide deterministic methods for controlled engineering of arbitrary quantum states. This work proposes a deterministic method for engineering arbitrary pure and mixed states of a wide class of quantum systems. The method exploits a special combination of incoherent and coherent controls (incoherent and coherent radiation) and has two properties which are specifically important for manipulating by quantum systems: it realizes the strongest possible degree of their state control, complete density matrix controllability, meaning the ability to steer arbitrary pure and mixed initial states into any desired pure or mixed final state, and it is all-to-one, such that each particular control transfers all initial system states into one target state.

  16. Pure Apraxia of Speech - A Case Report -

    PubMed Central

    Kang, Young Ae; Yun, Sang Jin

    2011-01-01

    Apraxia of speech (AOS) is the impairment of motor programming. However, the exact nature of this deficit remains unclear. In particular, AOS without other speech-language deficit is called pure AOS, but it is very rare. When diagnosing AOS, the characteristic of articulation is considered a crucial criterion, which has been proposed for differentiating AOS from phonological and dysarthric disorders. The present study reports on pure AOS in a 37-year-old right-handed male after a left insular, front, temporal infarction. This report may be useful for further AOS study and diagnosis in the clinical setting. PMID:22506197

  17. BRST and the pure spinor formalism

    SciTech Connect

    Garcia, J. Antonio

    2008-03-06

    The aim of this talk is to show the relation between the standard BRST approach of the GS superstring with the quantization technics used in the pure spinor approach to superstring. To that end we will use the Batalin-Fradkin-Tyutin (BFT) conversion program of second class constraints to first class constraints in the GS superstring using light cone coordinates. By applying this systematic procedure we were able to obtain a gauge system that is equivalent to the recent model proposed in [1] to relate the GS superstring to the pure spinor formalism.

  18. CCN activation of pure and coated carbon black particles.

    PubMed

    Dusek, U; Reischl, G P; Hitzenberger, R

    2006-02-15

    The CCN (cloud condensation nucleus) activation of pure and coated carbon black particles was investigated using the University of Vienna cloud condensation nuclei counter (Giebl, H.; Berner, A.; Reischl, G.; Puxbaum, H.; Kasper-Giebl, A.; Hitzenberger, R. J. Aerosol Sci. 2002, 33, 1623-1634). The particles were produced by nebulizing an aqueous suspension of carbon black in a Collison atomizer. The activation of pure carbon black particles was found to require higher supersaturations than predicted by calculations representing the particles as insoluble, wettable spheres with mobility equivalent diameter. To test whether this effect is an artifact due to heating of the light-absorbing carbon black particles in the laser beam, experiments at different laser powers were conducted. No systematic dependence of the activation of pure carbon black particles on laser power was observed. The observations could be modeled using spherical particles and an effective contact angle of 4-6 degrees of water at their surface. The addition of a small amount of NaCl to the carbon black particles (by adding 5% by mass NaCl to the carbon black suspension) greatly enhanced their CCN efficiency. The measured CCN efficiencies were consistent with Kohler theory for particles consisting of insoluble and hygroscopic material. However, coating the carbon black particles with hexadecanol (a typical film-forming compound with one hydrophobic and one hydrophilic end) efficiently suppressed the CCN activation of the carbon black particles.

  19. Uniform and accelerated degradation of pure iron patterned by Pt disc arrays

    PubMed Central

    Huang, Tao; Zheng, Yufeng

    2016-01-01

    Pure iron has been confirmed as a promising biodegradable metal. However, the degradation rate of pure iron should be accelerated to meet the clinical requirements. In this work, two different designs of platinum disc arrays, including sizes of Φ20 μm × S5 μm and Φ4 μm × S4 μm, have been coated on the surface of pure iron. Corrosion tests showed the platinum discs formed plenty of galvanic cells with the iron matrix which significantly accelerated the degradation of pure iron. Simultaneously, due to the designability of the shape, size as well as distribution of Pt discs, the degradation rate as well as degradation uniformity of pure iron can be effectively controlled by coating with platinum discs. The cytotoxicity test results unveiled that Pt discs patterned pure iron exhibited almost no toxicity to human umbilical vein endothelial cells, but a significant inhibition on proliferation of vascular smooth muscle cells. In addition, the hemolysis rate of Pt discs patterned pure iron was lower than 1%. Moreover, Pt discs also effectively reduced the number of adhered platelets. All these results indicated that Pt discs patterning is an effective way to accelerate degradation and improve biocompatibility of pure iron. PMID:27033380

  20. Uniform and accelerated degradation of pure iron patterned by Pt disc arrays.

    PubMed

    Huang, Tao; Zheng, Yufeng

    2016-04-01

    Pure iron has been confirmed as a promising biodegradable metal. However, the degradation rate of pure iron should be accelerated to meet the clinical requirements. In this work, two different designs of platinum disc arrays, including sizes of Φ20 μm × S5 μm and Φ4 μm × S4 μm, have been coated on the surface of pure iron. Corrosion tests showed the platinum discs formed plenty of galvanic cells with the iron matrix which significantly accelerated the degradation of pure iron. Simultaneously, due to the designability of the shape, size as well as distribution of Pt discs, the degradation rate as well as degradation uniformity of pure iron can be effectively controlled by coating with platinum discs. The cytotoxicity test results unveiled that Pt discs patterned pure iron exhibited almost no toxicity to human umbilical vein endothelial cells, but a significant inhibition on proliferation of vascular smooth muscle cells. In addition, the hemolysis rate of Pt discs patterned pure iron was lower than 1%. Moreover, Pt discs also effectively reduced the number of adhered platelets. All these results indicated that Pt discs patterning is an effective way to accelerate degradation and improve biocompatibility of pure iron.

  1. Uniform and accelerated degradation of pure iron patterned by Pt disc arrays

    NASA Astrophysics Data System (ADS)

    Huang, Tao; Zheng, Yufeng

    2016-04-01

    Pure iron has been confirmed as a promising biodegradable metal. However, the degradation rate of pure iron should be accelerated to meet the clinical requirements. In this work, two different designs of platinum disc arrays, including sizes of Φ20 μm × S5 μm and Φ4 μm × S4 μm, have been coated on the surface of pure iron. Corrosion tests showed the platinum discs formed plenty of galvanic cells with the iron matrix which significantly accelerated the degradation of pure iron. Simultaneously, due to the designability of the shape, size as well as distribution of Pt discs, the degradation rate as well as degradation uniformity of pure iron can be effectively controlled by coating with platinum discs. The cytotoxicity test results unveiled that Pt discs patterned pure iron exhibited almost no toxicity to human umbilical vein endothelial cells, but a significant inhibition on proliferation of vascular smooth muscle cells. In addition, the hemolysis rate of Pt discs patterned pure iron was lower than 1%. Moreover, Pt discs also effectively reduced the number of adhered platelets. All these results indicated that Pt discs patterning is an effective way to accelerate degradation and improve biocompatibility of pure iron.

  2. Generation of Pure Bulk Valley Current in Graphene

    NASA Astrophysics Data System (ADS)

    Jiang, Yongjin; Low, Tony; Chang, Kai; Katsnelson, Mikhail I.; Guinea, Francisco

    2013-01-01

    The generation of valley current is a fundamental goal in graphene valleytronics but no practical ways of its realization are known yet. We propose a workable scheme for the generation of bulk valley current in a graphene mechanical resonator through adiabatic cyclic deformations of the strains and a chemical potential in the suspended region. The accompanied strain gauge fields can break the spatial mirror symmetry of the problem within each of the two inequivalent valleys, leading to a finite valley current due to quantum pumping. An all-electrical measurement configuration is designed to detect the novel state with pure bulk valley currents.

  3. Purely hydrodynamic origin for swarming of swimming particles

    NASA Astrophysics Data System (ADS)

    Oyama, Norihiro; Molina, John Jairo; Yamamoto, Ryoichi

    2016-04-01

    Three-dimensional simulations with fully resolved hydrodynamics are performed to study the collective motion of model swimmers in bulk and confinement. Calculating the dynamic structure factor, we clarified that the swarming in bulk systems can be understood as a pseudoacoustic mode. Under confinement between flat parallel walls, this pseudoacoustic mode leads to a traveling wavelike motion. This swarming behavior is due purely to the hydrodynamic interactions between the swimmers and depends strongly on the type and strength of swimming (i.e., pusher or puller).

  4. Pure agraphia after deep left hemisphere haematoma.

    PubMed Central

    Croisile, B; Laurent, B; Michel, D; Trillet, M

    1990-01-01

    Pure agraphia is reported following haematoma in the left centrum semiovale sparing both parietal and frontal cortices. There was total inability to produce graphemes in the absence of limb apraxia. The lesion is assumed to have prevented linguistic and graphemic systems from gaining access to the frontal motor programme. Images PMID:2324759

  5. A fatal case of pure metaphyseal chondroblastoma.

    PubMed

    Binesh, Fariba; Moghadam, Reza Nafisi; Abrisham, Jalil

    2013-08-23

    The chondroblastoma (CB) is a rare cartilaginous tumour; it represents less than 1% of all bone tumours. It is mostly localised at the level of the epiphysis of long bones. We report a fatal case of pure metaphyseal CB of the tibia in a 9-year-old boy whose pulmonary metastases developed soon after operative therapy of the primary tumour.

  6. Temporal Ventriloquism in a Purely Temporal Context

    ERIC Educational Resources Information Center

    Hartcher-O'Brien, Jessica; Alais, David

    2011-01-01

    This study examines how audiovisual signals are combined in time for a temporal analogue of the ventriloquist effect in a purely temporal context, that is, no spatial grounding of signals or other spatial facilitation. Observers were presented with two successive intervals, each defined by a 1250-ms tone, and indicated in which interval a brief…

  7. Pure progressive amnesia: An atypical amnestic syndrome?

    PubMed

    Barbeau, Emmanuel J; Didic, Mira; Felician, Olivier; Tramoni, Eve; Guedj, Eric; Ceccaldi, Mathieu; Poncet, Michel

    2006-12-01

    We report on M.S., an 83-year-old patient with isolated pure progressive amnesia. This rare, recently identified, form of amnesia has been described in elderly patients. Neuropathological studies suggest that this syndrome is an atypical clinical presentation of Alzheimer's disease. The aim of our study was to characterize the neuropsychological pattern of pure progressive amnesia in comparison with other amnestic syndromes and memory dissociations reported in the literature. Our results indicate that pure progressive amnesia is characterized by a highly unusual dissociation in the realm of memory, with severe deficits on tests based on recognition and recall of verbal and visual single items, contrasting with relatively preserved anterograde autobiographical and spatial memory and normal recall of complex material such as stories. These findings suggest that memory for single items could depend on an independent system. One hypothesis is that M.S.'s unusual memory profile results from relative dysfunction of the ventral medial temporal lobe pathway. An alternative explanation implicates cognitive reserve. Further studies are required in order to progress on this matter. In any case, pure progressive amnesia is a clinical syndrome that may provide further insight into the organization of declarative memory.

  8. A fatal case of pure metaphyseal chondroblastoma.

    PubMed

    Binesh, Fariba; Moghadam, Reza Nafisi; Abrisham, Jalil

    2013-01-01

    The chondroblastoma (CB) is a rare cartilaginous tumour; it represents less than 1% of all bone tumours. It is mostly localised at the level of the epiphysis of long bones. We report a fatal case of pure metaphyseal CB of the tibia in a 9-year-old boy whose pulmonary metastases developed soon after operative therapy of the primary tumour. PMID:23975916

  9. Implicit Reading in Chinese Pure Alexia

    ERIC Educational Resources Information Center

    Shan, Chunlei; Zhu, Renjing; Xu, Mingwei; Luo, Benyan; Weng, Xuchu

    2010-01-01

    A number of recent studies have shown that some patients with pure alexia display evidence of implicit access to lexical and semantic information about words that they cannot read explicitly. This phenomenon has not been investigated systematically in Chinese patients. We report here a case study of a Chinese patient who met the criteria for pure…

  10. Pure science and the problem of progress.

    PubMed

    Douglas, Heather

    2014-06-01

    How should we understand scientific progress? Kuhn famously discussed science as its own internally driven venture, structured by paradigms. He also famously had a problem describing progress in science, as problem-solving ability failed to provide a clear rubric across paradigm change--paradigm changes tossed out problems as well as solving them. I argue here that much of Kuhn's inability to articulate a clear view of scientific progress stems from his focus on pure science and a neglect of applied science. I trace the history of the distinction between pure and applied science, showing how the distinction came about, the rhetorical uses to which the distinction has been put, and how pure science came to be both more valued by scientists and philosophers. I argue that the distinction between pure and applied science does not stand up to philosophical scrutiny, and that once we relinquish it, we can provide Kuhn with a clear sense of scientific progress. It is not one, though, that will ultimately prove acceptable. For that, societal evaluations of scientific work are needed.

  11. A Pure Theory of Lifelong Learning.

    ERIC Educational Resources Information Center

    Hatton, Michael J.

    Charles Tiebout's Pure Theory of Local Expenditures serves as a helpful framework in examining the emergence of the learning society, communications technologies, freer trade, and the effects these will have on the educational infrastructure. Tiebout argued that the failure of market-type systems of public good at the central government level does…

  12. Exploring the simplest purely baryonic decay processes

    NASA Astrophysics Data System (ADS)

    Geng, C. Q.; Hsiao, Y. K.; Rodrigues, Eduardo

    2016-07-01

    Though not considered in general, purely baryonic decays could shed light on the puzzle of the baryon number asymmetry in the universe by means of a better understanding of the baryonic nature of our matter world. As such, they constitute a yet unexplored class of decay processes worth investigating. We propose to search for purely baryonic decay processes at the LHCb experiment. No such type of decay has ever been observed. In particular, we concentrate on the decay Λb0→p p ¯n , which is the simplest purely baryonic decay mode, with solely spin-1 /2 baryons involved. We predict its decay branching ratio to be B (Λb0→p p ¯ n )=(2. 0-0.2+0.3)×10-6 , which is sufficiently large to make the decay mode accessible to LHCb. Our study can be extended to other purely baryonic decays such as Λb0→p p ¯ Λ , Λb0→Λ p ¯ Λ , and Λb0→Λ Λ ¯Λ , as well as to similar decays of antitriplet b baryons such as Ξb0 ,-.

  13. [A case of cerebral embolism due to cardiac myxoma presenting with multiple cerebral microaneurysms detected on first MRI scans].

    PubMed

    Sato, Takahiro; Saji, Naoki; Kobayashi, Kazuto; Shibazaki, Kensaku; Kimura, Kazumi

    2016-01-01

    A 64-year-old man developed right arm weakness and dysarthria, and was admitted to our hospital. Diffusion-weighted magnetic resonance imaging of the brain showed a high intensity area in the frontal lobe. T2*-weighted images showed multiple spotty low intensity lesions in bilateral cerebral hemispheres, mimicking cerebral microbleeds. Cerebral angiography showed multiple aneurysms in the anterior, middle, posterior cerebral arteries and cerebellar arteries. Transthoracic echocardiography revealed a floating structure in the left atrial chamber, indicating cardiac myxoma. We diagnosed cardioembolic ischemic stroke due to left atrial myxoma. Cardiac surgery for excision of a left atrial myxoma was performed on the 3rd hospital day. Multiple aneurysms should be taken into account for differential diagnosis in patients with cardiac myxoma and with atypical spotty low intensity on T2*-weighted images. PMID:26797485

  14. Effect of Surface Nanocrystallization on Fatigue Behavior of Pure Titanium

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Sun, Qiaoyan; Xiao, Lin; Sun, Jun

    2016-01-01

    The high-cycle fatigue behavior was investigated in pure titanium after surface nanocrystallization (SNC Ti). Compared with the coarse-grained titanium (CG Ti) samples, the SNC Ti samples exhibit an improved fatigue life. The SNC has a remarkable influence on the fatigue cracks initiation and growth of pure titanium. The results show that, because the free-surface cracking is suppressed by the surface nanogradient structure in the SNC Ti, the fatigue cracks initiation sites change from the free surface to the subsurface. Meanwhile, the fatigue crack growth rate decreases due to the microstructural feature and residual compressive stress. The deformation twins in the subsurface of SNC Ti have a marked effect on the fatigue crack initiation and the crack growth. The former effect is due to the twin boundaries being preferential sites for crack initiation, while the latter is associated with the barriers that the twin boundaries pose to the propagation of dislocations. Furthermore, microstructural analysis indicates that the dislocation distribution in SNC Ti gradually becomes homogenous as fatigue processes. This homogeneous microstructure is also beneficial to the improvement of fatigue life.

  15. Heat engine driven by purely quantum information.

    PubMed

    Park, Jung Jun; Kim, Kang-Hwan; Sagawa, Takahiro; Kim, Sang Wook

    2013-12-01

    The key question of this Letter is whether work can be extracted from a heat engine by using purely quantum mechanical information. If the answer is yes, what is its mathematical formula? First, by using a bipartite memory we show that the work extractable from a heat engine is bounded not only by the free energy change and the sum of the entropy change of an individual memory but also by the change of quantum mutual information contained inside the memory. We then find that the engine can be driven by purely quantum information, expressed as the so-called quantum discord, forming a part of the quantum mutual information. To confirm it, as a physical example we present the Szilard engine containing a diatomic molecule with a semipermeable wall.

  16. Pure field theories and MACSYMA algorithms

    NASA Technical Reports Server (NTRS)

    Ament, W. S.

    1977-01-01

    A pure field theory attempts to describe physical phenomena through singularity-free solutions of field equations resulting from an action principle. The physics goes into forming the action principle and interpreting specific results. Algorithms for the intervening mathematical steps are sketched. Vacuum general relativity is a pure field theory, serving as model and providing checks for generalizations. The fields of general relativity are the 10 components of a symmetric Riemannian metric tensor; those of the Einstein-Straus generalization are the 16 components of a nonsymmetric. Algebraic properties are exploited in top level MACSYMA commands toward performing some of the algorithms of that generalization. The light cone for the theory as left by Einstein and Straus is found and simplifications of that theory are discussed.

  17. Symmetries of Type N Pure Radiation Fields

    NASA Astrophysics Data System (ADS)

    Ahsan, Zafar; Ali, Musavvir

    2015-05-01

    The geometrical symmetries corresponding to the continuous groups of collineations and motions generated by a null vector l are considered. These symmetries have been translated into the language of Newman-Penrose formalism for pure radiation (PR) type N fields. It is seen that for such fields, conformal, special conformal and homothetic motions degenerate to motion. The concept of free curvature, matter curvature and matter affine collineations have been discussed and the conditions under which PR type N fields admit such collineations have been obtained. Moreover, it is shown that the projective collineation degenerate to matter affine, special projective, conformal, special conformal, null geodesic and special null geodesic collineations. It is also seen that type N pure radiation fields admit Maxwell collineation along the propagation vector l.

  18. Grip for fatigue testing pure aluminium

    NASA Astrophysics Data System (ADS)

    Lehmann, P.; Yuan, G. S.; Hartwig, K. T.

    A simple method of clamping pure aluminium for fatigue tests at cryogenic temperatures is described. Easily machined cylindrical specimens are aligned and held firmly by collet grips that counteract sample shrinkage during cooldown. Specimens are quickly mounted and removed after testing without distortion or thermal treatment 99.999% aluminium, aluminium alloys and copper were gripped successfully through tens of thousands of fully reversed tension-compression cycles at 295, 77 and 4.2 K.

  19. Pure connection action principle for general relativity.

    PubMed

    Krasnov, Kirill

    2011-06-24

    It has already been known for two decades that general relativity can be reformulated as a certain gauge theory, so that the only dynamical field is an SO(3) connection and the spacetime metric appears as a derived object. However, no simple action principle realizing these ideas has been available. A new elegant action principle for such a "pure connection" formulation of GR is described.

  20. Stable freestanding thin films of pure water

    SciTech Connect

    Weon, B. M.; Je, J. H.; Hwu, Y.; Margaritondo, G.

    2008-03-10

    Obtaining water microstructures is very difficult because of low viscosity and high surface tension. We produced stable freestanding thin films of pure water by x-ray bombardment of small liquid volumes in capillary tubes. A detailed characterization with phase-contrast radiology demonstrated a lifetime beyond 1 h with no chemical stabilizer for micron-thickness films with half-millimeter-level diameter. This can be attributed to the interplay of two x-ray effects: water evaporation and surface charging.

  1. On constructing purely affine theories with matter

    NASA Astrophysics Data System (ADS)

    Cervantes-Cota, Jorge L.; Liebscher, D.-E.

    2016-08-01

    We explore ways to obtain the very existence of a space-time metric from an action principle that does not refer to it a priori. Although there are reasons to believe that only a non-local theory can viably achieve this goal, we investigate here local theories that start with Schrödinger's purely affine theory (Schrödinger in Space-time structure. Cambridge UP, Cambridge, 1950), where he gave reasons to set the metric proportional to the Ricci curvature aposteriori. When we leave the context of unified field theory, and we couple the non-gravitational matter using some weak equivalence principle, we can show that the propagation of shock waves does not define a lightcone when the purely affine theory is local and avoids the explicit use of the Ricci tensor in realizing the weak equivalence principle. When the Ricci tensor is substituted for the metric, the equations seem to have only a very limited set of solutions. This backs the conviction that viable purely affine theories have to be non-local.

  2. The Dynamics of Spiral Arms in Pure Stellar Disks

    NASA Astrophysics Data System (ADS)

    Fujii, M. S.; Baba, J.; Saitoh, T. R.; Makino, J.; Kokubo, E.; Wada, K.

    2011-04-01

    It has been believed that spiral arms in pure stellar disks, especially the ones spontaneously formed, decay in several galactic rotations due to the increase of stellar velocity dispersions. Therefore, some cooling mechanism, for example dissipational effects of the interstellar medium, was assumed to be necessary to keep the spiral arms. Here, we show that stellar disks can maintain spiral features for several tens of rotations without the help of cooling, using a series of high-resolution three-dimensional N-body simulations of pure stellar disks. We found that if the number of particles is sufficiently large, e.g., 3 × 106, multi-arm spirals developed in an isolated disk can survive for more than 10 Gyr. We confirmed that there is a self-regulating mechanism that maintains the amplitude of the spiral arms. Spiral arms increase Toomre's Q of the disk, and the heating rate correlates with the squared amplitude of the spirals. Since the amplitude itself is limited by Q, this makes the dynamical heating less effective in the later phase of evolution. A simple analytical argument suggests that the heating is caused by gravitational scattering of stars by spiral arms and that the self-regulating mechanism in pure stellar disks can effectively maintain spiral arms on a cosmological timescale. In the case of a smaller number of particles, e.g., 3 × 105, spiral arms grow faster in the beginning of the simulation (while Q is small) and they cause a rapid increase of Q. As a result, the spiral arms become faint in several Gyr.

  3. Augmenting The HST Pure Parallel Observations

    NASA Astrophysics Data System (ADS)

    Patterson, Alan; Soutchkova, G.; Workman, W.

    2012-05-01

    Pure Parallel (PP) programs, designated GO/PAR, are a subgroup of General Observer (GO) programs. PP execute simultaneously with prime GO observations to which they are "attached". The PP observations can be performed with ACS/WFC, WFC3/UVIS or WFC3/IR and can be attached only to GO visits in which the instruments are either COS or STIS. The current HST Parallel Observation Processing System (POPS) was introduced after the Servicing Mission 4. It increased the HST productivity by 10% in terms of the utilization of HST prime orbits and was highly appreciated by the HST observers, allowing them to design efficient, multi-orbit survey projects for collecting large amounts of data on identifiable targets. The results of the WFC3 Infrared Spectroscopic Parallel Survey (WISP), Hubble Infrared Pure Parallel Imaging Extragalactic Survey (HIPPIES), and The Brightest-of-Reionizing Galaxies Pure Parallel Survey (BoRG) exemplify this benefit. In Cycle 19, however, the full advantage of GO/PARs came under risk. Whereas each of the previous cycles provided over one million seconds of exposure time for PP, in Cycle 19 that number reduced to 680,000 seconds. This dramatic decline occurred because of fundamental changes in the construction of COS prime observations. To preserve the science output of PP, the PP Working Group was tasked to find a way to recover the lost time and maximize the total time available for PP observing. The solution was to expand the definition of a PP opportunity to allow PP exposures to span one or more primary exposure readouts. So starting in HST Cycle 20, PP opportunities will no longer be limited to GO visits with a single uninterrupted exposure in an orbit. The resulting enhancements in HST Cycle 20 to the PP opportunity identification and matching process are expected to restore the PP time to previously achieved and possibly even greater levels.

  4. chemf: A purely functional chemistry toolkit

    PubMed Central

    2012-01-01

    Background Although programming in a type-safe and referentially transparent style offers several advantages over working with mutable data structures and side effects, this style of programming has not seen much use in chemistry-related software. Since functional programming languages were designed with referential transparency in mind, these languages offer a lot of support when writing immutable data structures and side-effects free code. We therefore started implementing our own toolkit based on the above programming paradigms in a modern, versatile programming language. Results We present our initial results with functional programming in chemistry by first describing an immutable data structure for molecular graphs together with a couple of simple algorithms to calculate basic molecular properties before writing a complete SMILES parser in accordance with the OpenSMILES specification. Along the way we show how to deal with input validation, error handling, bulk operations, and parallelization in a purely functional way. At the end we also analyze and improve our algorithms and data structures in terms of performance and compare it to existing toolkits both object-oriented and purely functional. All code was written in Scala, a modern multi-paradigm programming language with a strong support for functional programming and a highly sophisticated type system. Conclusions We have successfully made the first important steps towards a purely functional chemistry toolkit. The data structures and algorithms presented in this article perform well while at the same time they can be safely used in parallelized applications, such as computer aided drug design experiments, without further adjustments. This stands in contrast to existing object-oriented toolkits where thread safety of data structures and algorithms is a deliberate design decision that can be hard to implement. Finally, the level of type-safety achieved by Scala highly increased the reliability of our code

  5. Are all maximally entangled states pure?

    NASA Astrophysics Data System (ADS)

    Cavalcanti, D.; Brandão, F. G. S. L.; Terra Cunha, M. O.

    2005-10-01

    We study if all maximally entangled states are pure through several entanglement monotones. In the bipartite case, we find that the same conditions which lead to the uniqueness of the entropy of entanglement as a measure of entanglement exclude the existence of maximally mixed entangled states. In the multipartite scenario, our conclusions allow us to generalize the idea of the monogamy of entanglement: we establish the polygamy of entanglement, expressing that if a general state is maximally entangled with respect to some kind of multipartite entanglement, then it is necessarily factorized of any other system.

  6. Electrostatic Precipitation in Nearly Pure Gaseous Nitrogen

    NASA Technical Reports Server (NTRS)

    Buhler, Charles; Calle, Carlos; Clements, Sid; Cox, Bobby; Ritz, Mindy

    2008-01-01

    Electrostatic precipitation was performed in a nearly pure gaseous nitrogen system as a possible remedy for black dust contaminant from high pressure 6000 psi lines at the NASA Kennedy Space Center. The results of a prototype electrostatic precipitator that was built and tested using nitrogen gas at standard atmospheric pressures is presented. High voltage pulsed waveforms are generated using a rotating spark gap system at 30 Hz. A unique dust delivery system utilizing the Venturi effect was devised that supplies a given amount of dust per unit time for testing purposes.

  7. Preparation of a pure molecular quantum gas.

    PubMed

    Herbig, Jens; Kraemer, Tobias; Mark, Michael; Weber, Tino; Chin, Cheng; Nägerl, Hanns-Christoph; Grimm, Rudolf

    2003-09-12

    An ultracold molecular quantum gas is created by application of a magnetic field sweep across a Feshbach resonance to a Bose-Einstein condensate of cesium atoms. The ability to separate the molecules from the atoms permits direct imaging of the pure molecular sample. Magnetic levitation enables study of the dynamics of the ensemble on extended time scales. We measured ultralow expansion energies in the range of a few nanokelvin for a sample of 3000 molecules. Our observations are consistent with the presence of a macroscopic molecular matter wave. PMID:12934014

  8. Synthesis of highly phase pure BSCCO superconductors

    DOEpatents

    Dorris, S.E.; Poeppel, R.B.; Prorok, B.C.; Lanagan, M.T.; Maroni, V.A.

    1995-11-21

    An article and method of manufacture (Bi, Pb)-Sr-Ca-Cu-O superconductor are disclosed. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor. 5 figs.

  9. Synthesis of highly phase pure BSCCO superconductors

    DOEpatents

    Dorris, Stephen E.; Poeppel, Roger B.; Prorok, Barton C.; Lanagan, Michael T.; Maroni, Victor A.

    1995-01-01

    An article and method of manufacture of (Bi, Pb)-Sr-Ca-Cu-O superconductor. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor.

  10. Optical pure spin current injection in graphene

    NASA Astrophysics Data System (ADS)

    Rioux, Julien; Burkard, Guido

    2013-03-01

    Pure spin current injection by optical methods is investigated in single-layer and bilayer graphene within the tight-binding model, including bias and interlayer coupling effects. Interlayer coupling in bilayer graphene has a distinct qualitative effect on the polarization dependence of the spin current injection. In combination with interlayer coupling, which induces trigonal warping of the electronic bands, the bias voltage allows to control the warping at the Fermi surface. The resulting implications for the spin current injection are presented. Unlike the previously presented charge current injection [J. Rioux et al., PRB 83, 195406 (2011)], the effect presented here relies on a single monochromatic beam.

  11. Femtosecond pulses propagation through pure water

    NASA Astrophysics Data System (ADS)

    Naveira, Lucas; Sokolov, Alexei; Byeon, Joong-Hyeok; Kattawar, George

    2007-10-01

    Recently, considerable attention has been dedicated to the field of optical precursors, which can possibly be applied to long-distance underwater communications. Input beam intensities have been carefully adjusted to keep experiments in the linear regime, and some experiments have shown violation of the Beer-Lambert law. We are presently carrying out experiments using femtosecond laser pulses propagating through pure water strictly in the linear regime to study this interesting and important behavior. We are also employing several new and innovative schemes to more clearly define the phenomena.

  12. Purely cubic action for string field theory

    NASA Technical Reports Server (NTRS)

    Horowitz, G. T.; Lykken, J.; Rohm, R.; Strominger, A.

    1986-01-01

    It is shown that Witten's (1986) open-bosonic-string field-theory action and a closed-string analog can be written as a purely cubic interaction term. The conventional form of the action arises by expansion around particular solutions of the classical equations of motion. The explicit background dependence of the conventional action via the Becchi-Rouet-Stora-Tyutin operator is eliminated in the cubic formulation. A closed-form expression is found for the full nonlinear gauge-transformation law.

  13. Towards chirality-pure carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Zhang, Yani; Zheng, Lianxi

    2010-10-01

    Current as-grown single-walled carbon nanotubes vary in diameter and chirality, which results in variations in their electronic and optical properties. Two approaches have been intensively studied to obtain chirality-pure nanotube structures and thus uniform properties for advanced applications. The first approach involves the post-synthesis separation according to the nanotubes' chiral vectors (n, m), and the second one involves direct synthes of carbon nanotubes with the same (n, m). This paper reviews the efforts along these two directions, with emphasis on the most recent progress of post-synthesis separation and the perspectives of controllable synthesis.

  14. Are all maximally entangled states pure?

    SciTech Connect

    Cavalcanti, D.; Brandao, F.G.S.L.; Terra Cunha, M.O.

    2005-10-15

    We study if all maximally entangled states are pure through several entanglement monotones. In the bipartite case, we find that the same conditions which lead to the uniqueness of the entropy of entanglement as a measure of entanglement exclude the existence of maximally mixed entangled states. In the multipartite scenario, our conclusions allow us to generalize the idea of the monogamy of entanglement: we establish the polygamy of entanglement, expressing that if a general state is maximally entangled with respect to some kind of multipartite entanglement, then it is necessarily factorized of any other system.

  15. Cold-Sprayed Nanostructured Pure Cobalt Coatings

    NASA Astrophysics Data System (ADS)

    Cavaliere, P.; Perrone, A.; Silvello, A.

    2016-08-01

    Cold-sprayed pure cobalt coatings were deposited on carbon-steel substrate. Submicrometer particles for spraying were produced via cryomilling. Deposits were produced using different processing conditions (gas temperature and pressure, nozzle-to-substrate distance) to evaluate the resulting variations in grain size dimension, microhardness, adhesion strength, and porosity. The coating mechanical properties improved greatly with higher temperature and carrying-gas pressure. The coating microstructure was analyzed as a function of spraying condition by transmission electron microscopy (TEM) observations, revealing many different microstructural features for coatings experiencing low or high strain rates during deposition.

  16. Pure seminoma: A review and update

    PubMed Central

    2011-01-01

    Pure seminoma is a rare pathology of the young adult, often discovered in the early stages. Its prognosis is generally excellent and many therapeutic options are available, especially in stage I tumors. High cure rates can be achieved in several ways: standard treatment with radiotherapy is challenged by surveillance and chemotherapy. Toxicity issues and the patients' preferences should be considered when management decisions are made. This paper describes firstly the management of primary seminoma and its nodal involvement and, secondly, the various therapeutic options according to stage. PMID:21819630

  17. Pure phase decoherence in a ring geometry

    SciTech Connect

    Zhu, Z.; Aharony, A.; Entin-Wohlman, O.; Stamp, P. C. E.

    2010-06-15

    We study the dynamics of pure phase decoherence for a particle hopping around an N-site ring, coupled both to a spin bath and to an Aharonov-Bohm flux which threads the ring. Analytic results are found for the dynamics of the influence functional and of the reduced density matrix of the particle, both for initial single wave-packet states, and for states split initially into two separate wave packets moving at different velocities. We also give results for the dynamics of the current as a function of time.

  18. Lattice Strain Due to an Atomic Vacancy

    PubMed Central

    Li, Shidong; Sellers, Michael S.; Basaran, Cemal; Schultz, Andrew J.; Kofke, David A.

    2009-01-01

    Volumetric strain can be divided into two parts: strain due to bond distance change and strain due to vacancy sources and sinks. In this paper, efforts are focused on studying the atomic lattice strain due to a vacancy in an FCC metal lattice with molecular dynamics simulation (MDS). The result has been compared with that from a continuum mechanics method. It is shown that using a continuum mechanics approach yields constitutive results similar to the ones obtained based purely on molecular dynamics considerations. PMID:19582230

  19. A pure hydrodynamic origin of accretion disk turbulence

    NASA Astrophysics Data System (ADS)

    Nath, Sujit Kumar; Mukhopadhyay, Banibrata

    2016-07-01

    Accretion disks consist of flows for which angular velocity decreases but specific angular momentum increases with increasing radial coordinate. Such flows are Rayleigh stable, but must be turbulent in order to explain observed data. Since molecular viscosity is negligible in these systems, scientists have argued for turbulent viscosity for energy dissipation and hence to explain infall of matter. However, so far, the success to explain the origin of turbulence in accretion disks is done with caveats. Here we investigate the evolution of pure hydrodynamic perturbations in stochastically driven accretion disks. We show that the accretion flows, which are inevitably driven by stochastic noise, are hydrodynamically unstable under linear perturbations. We also argue that in accretion disks, stochastic forcing appears generically due to the presence of shear between different annuli of the disk. This work resolves the turbulence problem of accretion disks from pure hydrodynamics and explains the infall of matter for both hot and cold disks. This would help in explaining the origin of timing and spectral features in the disk flows generically.

  20. LHC Signals of Pure Gravity Mediation

    NASA Astrophysics Data System (ADS)

    Feldstein, Brian

    2013-05-01

    Evidence is mounting that natural supersymmetry at the weak scale is not realized in nature. This evidence comes from collider searches, a lack of new flavor changing neutral current effects, and now also the size of the measured Higgs mass. On the other hand, string theory suggests that supersymmetry might be present at some energy scale, and gauge coupling unification and dark matter imply that that energy scale may be relatively low. The simplest model to address all of these hints is arguably "pure gravity mediation", in which the scalar superpartner masses are taken to be perhaps 100 TeV, with gauginos automatically acquiring loop factor suppressed masses of order TeV. The gauginos might then be the only superpartners accessible to the LHC. Unification and LSP dark matter are maintained (with a wino LSP) at the cost of a 10-5 or 10-6 fine tuning. Here I will discuss the structure and LHC phenomenology of pure gravity mediation.

  1. Light Higgsinos in pure gravity mediation

    NASA Astrophysics Data System (ADS)

    Evans, Jason L.; Ibe, Masahiro; Olive, Keith A.; Yanagida, Tsutomu T.

    2015-03-01

    Pure gravity mediation, with two free parameters, is a minimalistic approach to supergravity models, yet it is capable of incorporating radiative electroweak symmetry breaking, a Higgs mass in agreement with the experimental measurement, without violating any phenomenological constraints. The model may also contain a viable dark matter candidate in the form of a wino. Here, we extend the minimal model by allowing the μ term to be a free parameter equivalent to allowing the two Higgs soft masses, m1 and m2, to differ from other scalar masses, which are set by the gravitino mass. In particular, we examine the region of parameter space where μ ≪m3 /2, in which case the Higgsino becomes the lightest supersymmetric particle and a dark matter candidate. We also consider a generalization of pure gravity mediation that incorporates a Peccei-Quinn symmetry which determines the μ term dynamically. In this case we show that the dark matter may either be in the form of an axion and/or a neutralino and that the lightest supersymmetric particle may be either a wino, bino, or Higgsino.

  2. Time Evolution of Pure Gravitational Waves

    NASA Astrophysics Data System (ADS)

    Miyama, S. M.

    1981-03-01

    Numerical solutions to the Einstein equations in the case of pure gravitational waves are given. The system is assumed to be axially symmetric and non-rotating. The time symmetric initial data and the conformally flat initial data are obtained by solving the constraint equations at t=0. The time evolution of these initial data depends strongly on the initial amplitude of the gravitational waves. In the case of the low initial amplitude, waves only disperse to null infinity. By comparing the initial gravitational energy with the total energy loss through an r=constant surface, it is concluded that the Newman-Penrose method and the Gibbon-Hawking method are the most desirable for measuring the energy flux of gravitational radiation numerically. In the case that the initial ratio of the spatial extent of the gravitational waves to the Schwarzschild radius (M/2) is smaller than about 300, the waves collapse by themselves, leading to formation of a black hole. The analytic solutions of the linearized Einstein equations for the pure gravitational waves are also shown.

  3. Pure spin current devices based on ferromagnetic topological insulators

    PubMed Central

    Götte, Matthias; Joppe, Michael; Dahm, Thomas

    2016-01-01

    Two-dimensional topological insulators possess two counter propagating edge channels with opposite spin direction. Recent experimental progress allowed to create ferromagnetic topological insulators realizing a quantum anomalous Hall (QAH) state. In the QAH state one of the two edge channels disappears due to the strong ferromagnetic exchange field. We investigate heterostructures of topological insulators and ferromagnetic topological insulators by means of numerical transport calculations. We show that spin current flow in such heterostructures can be controlled with high fidelity. Specifically, we propose spintronic devices that are capable of creating, switching and detecting pure spin currents using the same technology. In these devices electrical currents are directly converted into spin currents, allowing a high conversion efficiency. Energy independent transport properties in combination with large bulk gaps in some topological insulator materials may allow operation even at room temperature. PMID:27782187

  4. Mathematical properties and bounds on haplotyping populations by pure parsimony.

    PubMed

    Wang, I-Lin; Chang, Chia-Yuan

    2011-06-01

    Although the haplotype data can be used to analyze the function of DNA, due to the significant efforts required in collecting the haplotype data, usually the genotype data is collected and then the population haplotype inference (PHI) problem is solved to infer haplotype data from genotype data for a population. This paper investigates the PHI problem based on the pure parsimony criterion (HIPP), which seeks the minimum number of distinct haplotypes to infer a given genotype data. We analyze the mathematical structure and properties for the HIPP problem, propose techniques to reduce the given genotype data into an equivalent one of much smaller size, and analyze the relations of genotype data using a compatible graph. Based on the mathematical properties in the compatible graph, we propose a maximal clique heuristic to obtain an upper bound, and a new polynomial-sized integer linear programming formulation to obtain a lower bound for the HIPP problem.

  5. Biocorrosion properties and blood and cell compatibility of pure iron as a biodegradable biomaterial.

    PubMed

    Zhang, Erlin; Chen, Haiyan; Shen, Feng

    2010-07-01

    Biocorrosion properties and blood- and cell compatibility of pure iron were studied in comparison with 316L stainless steel and Mg-Mn-Zn magnesium alloy to reveal the possibility of pure iron as a biodegradable biomaterial. Both electrochemical and weight loss tests showed that pure iron showed a relatively high corrosion rate at the first several days and then decreased to a low level during the following immersion due to the formation of phosphates on the surface. However, the corrosion of pure iron did not cause significant increase in pH value to the solution. In comparison with 316L and Mg-Mn-Zn alloy, the pure iron exhibited biodegradable property in a moderate corrosion rate. Pure iron possessed similar dynamic blood clotting time, prothrombin time and plasma recalcification time to 316L and Mg-Mn-Zn alloy, but a lower hemolysis ratio and a significant lower number density of adhered platelets. MTT results revealed that the extract except the one with 25% 24 h extract actually displayed toxicity to cells and the toxicity increased with the increasing of the iron ion concentration and the incubation time. It was thought there should be an iron ion concentration threshold in the effect of iron ion on the cell toxicity.

  6. Bipedal nanowalker by pure physical mechanisms.

    PubMed

    Cheng, Juan; Sreelatha, Sarangapani; Hou, Ruizheng; Efremov, Artem; Liu, Ruchuan; van der Maarel, Johan R C; Wang, Zhisong

    2012-12-01

    Artificial nanowalkers are inspired by biomolecular counterparts from living cells, but remain far from comparable to the latter in design principles. The walkers reported to date mostly rely on chemical mechanisms to gain a direction; they all produce chemical wastes. Here we report a light-powered DNA bipedal walker based on a design principle derived from cellular walkers. The walker has two identical feet and the track has equal binding sites; yet the walker gains a direction by pure physical mechanisms that autonomously amplify an intrasite asymmetry into a ratchet effect. The nanowalker is free of any chemical waste. It has a distinct thermodynamic feature that it possesses the same equilibrium before and after operation, but generates a truly nonequilibrium distribution during operation. The demonstrated design principle exploits mechanical effects and is adaptable for use in other nanomachines.

  7. Pure White Cell Aplasia and Necrotizing Myositis

    PubMed Central

    Kim, Peter Geon; Suh, Joome; Adelman, Max W.; Oduro, Kwadwo; Williams, Erik; Brunner, Andrew M.; Kuter, David J.

    2016-01-01

    Pure white cell aplasia (PWCA) is a rare hematologic disorder characterized by the absence of neutrophil lineages in the bone marrow with intact megakaryopoiesis and erythropoiesis. PWCA has been associated with autoimmune, drug-induced, and viral exposures. Here, we report a case of a 74-year-old female who presented with severe proximal weakness without pain and was found to have PWCA with nonspecific inflammatory necrotizing myositis and acute liver injury on biopsies. These findings were associated with a recent course of azithromycin and her daily use of a statin. Myositis improved on prednisone but PWCA persisted. With intravenous immunoglobulin and granulocyte-colony stimulating factor therapies, her symptoms and neutrophil counts improved and were sustained for months. PMID:27073704

  8. Fock expansion of multimode pure Gaussian states

    SciTech Connect

    Cariolaro, Gianfranco; Pierobon, Gianfranco

    2015-12-15

    The Fock expansion of multimode pure Gaussian states is derived starting from their representation as displaced and squeezed multimode vacuum states. The approach is new and appears to be simpler and more general than previous ones starting from the phase-space representation given by the characteristic or Wigner function. Fock expansion is performed in terms of easily evaluable two-variable Hermite–Kampé de Fériet polynomials. A relatively simple and compact expression for the joint statistical distribution of the photon numbers in the different modes is obtained. In particular, this result enables one to give a simple characterization of separable and entangled states, as shown for two-mode and three-mode Gaussian states.

  9. Pure Varus Injury to the Knee Joint.

    PubMed

    Yoo, Jae Ho; Lee, Jung Ha; Chang, Chong Bum

    2015-06-01

    A 30-year-old male was involved in a car accident. Radiographs revealed a depressed marginal fracture of the medial tibial plateau and an avulsion fracture of the fibular head. Magnetic resonance imaging showed avulsion fracture of Gerdy's tubercle, injury to the posterior cruciate ligament (PCL), posterior horn of the medial meniscus, and the attachments of the lateral collateral ligament and the biceps femoris tendon. The depressed fracture of the medial tibial plateau was elevated and stabilized using a cannulated screw and washer. The injured lateral and posterolateral corner (PLC) structures were repaired and augmented by PLC reconstruction. However, the avulsion fracture of Gerdy's tubercle was not fixed because it was minimally displaced and the torn PCL was also not repaired or reconstructed. We present a unique case of pure varus injury to the knee joint. This case contributes to our understanding of the mechanism of knee injury and provides insight regarding appropriate treatment plans for this type of injury. PMID:26217477

  10. Adsorption of hydroxyacetone on pure ice surfaces.

    PubMed

    Petitjean, Mélanie; Darvas, Maria; Picaud, Sylvain; Jedlovszky, Pál; Le Calvé, Stéphane

    2010-12-17

    The adsorption of hydroxyacetone molecules at the surface of ice is investigated by means of flow-tube reactor measurements in the temperature range: 213-253 K. The number of molecules adsorbed per surface unit is conventionally plotted as a function of the absolute gas concentration of hydroxyacetone and is compared to that previously obtained for acetone and ethanol. The enthalpy of adsorption and the monolayer capacity at the ice surface are determined. In addition, molecular dynamics simulations are performed to support the experimental results. However, it is shown that the available interaction potential between hydroxyacetone and ice is not accurate enough to allow a robust detailed analysis of the adsorption process. Finally, a rapid estimation of the hydroxyacetone partitioning between the gas phase and ice shows that in the densest ice clouds, up to 29% of hydroxyacetone could be adsorbed on pure ice surfaces at 203 K.

  11. Synaptic devices based on purely electronic memristors

    NASA Astrophysics Data System (ADS)

    Pan, Ruobing; Li, Jun; Zhuge, Fei; Zhu, Liqiang; Liang, Lingyan; Zhang, Hongliang; Gao, Junhua; Cao, Hongtao; Fu, Bing; Li, Kang

    2016-01-01

    Memristive devices have been widely employed to emulate biological synaptic behavior. In these cases, the memristive switching generally originates from electrical field induced ion migration or Joule heating induced phase change. In this letter, the Ti/ZnO/Pt structure was found to show memristive switching ascribed to a carrier trapping/detrapping of the trap sites (e.g., oxygen vacancies or zinc interstitials) in ZnO. The carrier trapping/detrapping level can be controllably adjusted by regulating the current compliance level or voltage amplitude. Multi-level conductance states can, therefore, be realized in such memristive device. The spike-timing-dependent plasticity, an important Hebbian learning rule, has been implemented in this type of synaptic device. Compared with filamentary-type memristive devices, purely electronic memristors have potential to reduce their energy consumption and work more stably and reliably, since no structural distortion occurs.

  12. Pure Rotational Spectroscopy of Vinyl Mercaptan

    NASA Astrophysics Data System (ADS)

    Martin-Drumel, Marie-Aline; Zingsheim, Oliver; Thorwirth, Sven; Müller, Holger S. P.; Lewen, Frank; Schlemmer, Stephan

    2014-06-01

    Vinyl mercaptan (ethenethiol, CH_2=CHSH) exists in the gas phase in two distinct rotameric forms, syn (planar) and anti (quasi-planar in the ground vibrational state). The microwave spectra of these two isomers were investigated previously, however not exceeding frequencies of about 65 GHz. In the present investigation, the pure rotational spectra of both species have been investigated at millimeter wavelengths. Vinyl mercaptan was produced in a radiofrequency discharge through a constant flow of ethanedithiol at low pressure. Both syn and anti rotamers were observed and new extensive sets of molecular parameters were obtained. Owing to its close structural relationship to vinyl alcohol and the astronomical abundance of complex sulfur-bearing molecules, vinyl mercaptan is a plausible candidate for future radio astronomical searches. M. Tanimoto et al. J. Mol. Spectrosc. 78, 95--105 & 106--119 (1979)

  13. 7 CFR 201.64 - Pure live seed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Pure live seed. 201.64 Section 201.64 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Tolerances § 201.64 Pure live seed. The tolerance for pure live seed shall be determined...

  14. 7 CFR 201.64 - Pure live seed.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Pure live seed. 201.64 Section 201.64 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Tolerances § 201.64 Pure live seed. The tolerance for pure live seed shall be determined...

  15. 7 CFR 201.64 - Pure live seed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Pure live seed. 201.64 Section 201.64 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Tolerances § 201.64 Pure live seed. The tolerance for pure live seed shall be determined...

  16. 7 CFR 201.64 - Pure live seed.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Pure live seed. 201.64 Section 201.64 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Tolerances § 201.64 Pure live seed. The tolerance for pure live seed shall be determined...

  17. 7 CFR 201.64 - Pure live seed.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Pure live seed. 201.64 Section 201.64 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Tolerances § 201.64 Pure live seed. The tolerance for pure live seed shall be determined...

  18. ThermoData Engine Database - Pure Compounds and Binary Mixtures

    National Institute of Standards and Technology Data Gateway

    SRD 103b NIST ThermoData Engine Version 6.0 - Pure CompoThermoData Engine Database - Pure Compounds and Binary Mixtures (PC database for purchase)   This database contains property data for more than 21,000 pure compounds, 37,500 binary mixtures, 10,000 ternary mixtures, and 6,000 chemical reactions.

  19. Clinical study of 39 patients with atypical lacunar syndrome.

    PubMed

    Arboix, A; López-Grau, M; Casasnovas, C; García-Eroles, L; Massons, J; Balcells, M

    2006-03-01

    The aim of this study was to describe the clinical characteristics of atypical lacunar syndrome (ALS) based on data collected from a prospective acute stroke registry. In total, 2500 acute stroke patients were included in a hospital based prospective stroke registry over a 12 year period, of whom 39 were identified as having ALS and radiologically proven (by computed tomography or magnetic resonance imaging) lacunes. ALS accounted for 1.8% of all acute stroke patients, 2.1% of acute ischaemic stroke, and 6.8% of lacunar syndromes. ALS included dysarthria facial paresis (n = 12) or isolate dysarthria (n = 9), isolated hemiataxia (n = 4), pure motor hemiparesis with transient internuclear ophthalmoplegia (n = 4), pure motor hemiparesis with transient subcortical aphasia (n = 3), unilateral (n = 2) or bilateral (n = 3) paramedian thalamic infarct syndrome, and hemichorea hemiballismus (n = 2). Atypical lacunar syndromes were due to small vessel disease in 96% of patients. Atherothrombotic infarction occurred in one patient and cardioembolic infarct in another, both presenting pure dysarthria. Outcome was good (in hospital mortality 0%, symptom free at discharge 28.2%). After multivariate analysis, the variables of speech disturbances, nausea/vomiting, ischaemic heart disease, and sensory symptoms were found to be significantly associated with ALS. In conclusion, atypical lacunar syndrome is an infrequent stroke subtype (one of each 14 lacunar strokes). ALS occurred in 6.8% of lacunar strokes. Isolated dysarthria or dysarthria facial paresis were the most frequent presenting forms. The prognosis of this infrequent non-classic lacunar syndrome is good.

  20. Self-Esteem in Pure Bullies and Bully/Victims: A Longitudinal Analysis

    ERIC Educational Resources Information Center

    Pollastri, Alisha R.; Cardemil,, Esteban V.; O'Donnell, Ellen H.

    2010-01-01

    Past research on the self-esteem of bullies has produced equivocal results. Recent studies have suggested that the inconsistent findings may be due, in part, to the failure to account for bully/victims: those children who both bully and are victims of bullying. In this longitudinal study, we examined the distinctions among pure bullies, pure…

  1. Accelerating degradation rate of pure iron by zinc ion implantation.

    PubMed

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-12-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications. PMID:27482462

  2. Accelerating degradation rate of pure iron by zinc ion implantation

    PubMed Central

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-01-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications. PMID:27482462

  3. Stable pure state quantum tomography from five orthonormal bases

    NASA Astrophysics Data System (ADS)

    Carmeli, Claudio; Heinosaari, Teiko; Kech, Michael; Schultz, Jussi; Toigo, Alessandro

    2016-08-01

    For any finite-dimensional Hilbert space, we construct explicitly five orthonormal bases such that the corresponding measurements allow for efficient tomography of an arbitrary pure quantum state. This means that such measurements can be used to distinguish an arbitrary pure state from any other state, pure or mixed, and the pure state can be reconstructed from the outcome distribution in a feasible way. The set of measurements we construct is independent of the unknown state, and therefore our results provide a fixed scheme for pure state tomography, as opposed to the adaptive (state-dependent) scheme proposed by Goyeneche et al. (Phys. Rev. Lett., 115 (2015) 090401). We show that our scheme is robust with respect to noise, in the sense that any measurement scheme which approximates these measurements well enough is equally suitable for pure state tomography. Finally, we present two convex programs which can be used to reconstruct the unknown pure state from the measurement outcome distributions.

  4. AgraPure Mississippi Biomass Project

    SciTech Connect

    Blackwell,D.A; Broadhead, L.W.; Harrell, W.J.

    2006-03-31

    The AgraPure Mississippi Biomass project was a congressionally directed project, initiated to study the utilization of Mississippi agricultural byproducts and waste products in the production of bio-energy and to determine the feasibility of commercialization of these agricultural byproducts and waste products as feedstocks in the production of energy. The final products from this project were two business plans; one for a Thermal plant, and one for a Biodiesel/Ethanol plant. Agricultural waste fired steam and electrical generating plants and biodiesel plants were deemed the best prospects for developing commercially viable industries. Additionally, oil extraction methods were studied, both traditional and two novel techniques, and incorporated into the development plans. Mississippi produced crop and animal waste biomasses were analyzed for use as raw materials for both industries. The relevant factors, availability, costs, transportation, storage, location, and energetic value criteria were considered. Since feedstock accounts for more than 70 percent of the total cost of producing biodiesel, any local advantages are considered extremely important in developing this particular industry. The same factors must be evaluated in assessing the prospects of commercial operation of a steam and electrical generation plant. Additionally, the access to the markets for electricity is more limited, regulated and tightly controlled than the liquid fuel markets. Domestically produced biofuels, both biodiesel and ethanol, are gaining more attention and popularity with the consuming public as prices rise and supplies of foreign crude become less secure. Biodiesel requires no major modifications to existing diesel engines or supply chain and offers significant environmental benefits. Currently the biodiesel industry requires Federal and State incentives to allow the industry to develop and become self-sustaining. Mississippi has available the necessary feedstocks and is

  5. Adsorption of surfactants on mineral oxide surfaces from aqueous solutions. Part 1. Isomerically pure anionic surfactants

    SciTech Connect

    Scamehorn, J.F.; Schechter, R.S.; Wade, W.H.

    1982-02-01

    The adsorption of surfactants on minerals is detrimental to surfactant-enhanced oil recovery. To minimize adsorption, the forces tending to cause it must be understood. This requires the study of relatively simple, well-defined systems. The majority of surfactant adsorption studies on mineral oxides has been made with surfactant mixtures and not with monoisomerically pure species. Some of the observed results may be due to complex surfactant intercomponent interactions. In this study, the adsorption of 3 isomerically pure alkylbenzene sulfonates was measured on alumina and kaolinite from very low concentrations to well above the critical micelle concentration and a thermodynamic model was developed, which describes the observed isotherms. 59 references.

  6. Pure sensory stroke from compression of putaminal haemorrhage: a case report

    PubMed Central

    2009-01-01

    Introduction The literature rarely describes putaminal haemorrhage producing pure spinothalamic sensory deficit. Here reports a case of putaminal haemorrhage in which selective impairment of the spinothalamic sensory modality was due to the compression of the hematoma. Case presentation A 57 year old hypertensive man presented with a pure sensory stroke(PSS), and CT scan showed a putaminal haemorrhage. The clinical course was characterized by rapid resolution of the deficits. Conclusion This case illustrates this rarely of PSS from compression of putaminal haemorrhage of good functional and vital prognosis, and stresses the value of CT scanning for diagnosis and prognosis. PMID:19133162

  7. Memory for pure tone sequences without contour.

    PubMed

    Lefebvre, Christine; Jolicœur, Pierre

    2016-06-01

    We presented pure tones interspersed with white noise sounds to disrupt contour perception in an acoustic short-term memory (ASTM) experiment during which we recorded the electroencephalogram. The memory set consisted of seven stimuli, 0, 1, 2, 3, or 4 of which were to-be-remembered tones. We estimated each participant׳s capacity, K, for each set size and measured the amplitude of the SAN (sustained anterior negativity, an ERP related to acoustic short-term memory). We correlated their K slopes with their SAN amplitude slopes as a function of set size, and found a significant link between performance and the SAN: a larger increase in SAN amplitude was linked with a larger number of stimuli maintained in ASTM. The SAN decreased in amplitude in the later portion of the silent retention interval, but the correlation between the SAN and capacity remained strong. These results show the SAN is not an index of contour but rather an index of the maintenance of individual objects in STM. This article is part of a Special Issue entitled SI: Auditory working memory. PMID:26903419

  8. Electron Acoustic Waves in Pure Ion Plasmas

    NASA Astrophysics Data System (ADS)

    Anderegg, F.; Affolter, M.; Driscoll, C. F.; O'Neil, T. M.; Valentini, F.

    2012-10-01

    Electron Acoustic Waves (EAWs) are the low-frequency branch of near-linear Langmuir (plasma) waves: the frequency is such that the complex dielectric function (Dr, Di) has Dr= 0; and ``flattening'' of f(v) near the wave phase velocity vph gives Di=0 and eliminates Landau damping. Here, we observe standing axisymmetric EAWs in a pure ion column.footnotetextF. Anderegg, et al., Phys. Rev. Lett. 102, 095001 (2009). At low excitation amplitudes, the EAWs have vph˜1.4 v, in close agreement with near-linear theory. At moderate excitation strengths, EAW waves are observed over a range of frequencies, with 1.3 v < vph< 2.1 v. Here, the final wave frequency may differ from the excitation frequency since the excitation modifies f (v); and recent theory analyzes frequency shifts from ``corners'' of a plateau at vph.footnotetextF. Valentini et al., arXiv:1206.3500v1. Large amplitude EAWs have strong phase-locked harmonic content, and experiments will be compared to same-geometry simulations, and to simulations of KEENfootnotetextB. Afeyan et al., Proc. Inertial Fusion Sci. and Applications 2003, A.N.S. Monterey (2004), p. 213. waves in HEDLP geometries.

  9. Peccei-Quinn symmetric pure gravity mediation

    NASA Astrophysics Data System (ADS)

    Evans, Jason L.; Ibe, Masahiro; Olive, Keith A.; Yanagida, Tsutomu T.

    2014-07-01

    Successful models of pure gravity mediation (PGM) with radiative electroweak symmetry breaking can be expressed with as few as two free parameters, which can be taken as the gravitino mass and . These models easily support a 125-126 GeV Higgs mass at the expense of a scalar spectrum in the multi-TeV range and a much lighter wino as the lightest supersymmetric particle. In these models, it is also quite generic that the Higgs mixing mass parameter, , which is determined by the minimization of the Higgs potential is also in the multi-TeV range. For , the thermal relic density of winos is too small to account for the dark matter. The same is true for unless the gravitino mass is of order 500 TeV. Here, we consider the origin of a multi-TeV parameter arising from the breakdown of a Peccei-Quinn (PQ) symmetry. A coupling of the PQ-symmetry breaking field, , to the MSSM Higgs doublets, naturally leads to a value of TeV and of the order that is required in PGM models. In this case, axions make up the dark matter or some fraction of the dark matter with the remainder made up from thermal or non-thermal winos. We also provide solutions to the problem of isocurvature fluctuations with axion dark matter in this context.

  10. Memory for pure tone sequences without contour.

    PubMed

    Lefebvre, Christine; Jolicœur, Pierre

    2016-06-01

    We presented pure tones interspersed with white noise sounds to disrupt contour perception in an acoustic short-term memory (ASTM) experiment during which we recorded the electroencephalogram. The memory set consisted of seven stimuli, 0, 1, 2, 3, or 4 of which were to-be-remembered tones. We estimated each participant׳s capacity, K, for each set size and measured the amplitude of the SAN (sustained anterior negativity, an ERP related to acoustic short-term memory). We correlated their K slopes with their SAN amplitude slopes as a function of set size, and found a significant link between performance and the SAN: a larger increase in SAN amplitude was linked with a larger number of stimuli maintained in ASTM. The SAN decreased in amplitude in the later portion of the silent retention interval, but the correlation between the SAN and capacity remained strong. These results show the SAN is not an index of contour but rather an index of the maintenance of individual objects in STM. This article is part of a Special Issue entitled SI: Auditory working memory.

  11. Pure inorganic separator for lithium ion batteries.

    PubMed

    He, Meinan; Zhang, Xinjie; Jiang, Kuiyang; Wang, Joe; Wang, Yan

    2015-01-14

    Battery safety is critical for many applications including portable electronics, hybrid and electric vehicles, and grid storage. For lithium ion batteries, the conventional polymer based separator is unstable at 120 °C and above. In this research, we have developed a pure aluminum oxide nanowire based separator; this separator does not contain any polymer additives or binders; additionally, it is a bendable ceramic. The physical and electrochemical properties of the separator are investigated. The separator has a pore size of about 100 nm, and it shows excellent electrochemical properties under both room and high temperatures. At room temperature, the ceramic separator shows a higher rate capability compared to the conventional Celgard 2500 separator and life cycle performance does not show any degradation. At 120 °C, the cell with the ceramic separator showed a much better cycle performance than the conventional Celgard 2500 separator. Therefore, we believe that this research is really an exciting scientific breakthrough for ceramic separators and lithium ion batteries and could be potentially used in the next generation lithium ion batteries requiring high safety and reliability.

  12. Shifting from preconceptions to pure wonderment.

    PubMed

    Porr, Caroline

    2005-07-01

    The author reflects upon her role as a public health nurse striving to attain practice authenticity. Client assessment and nursing interventions were seemingly sufficient until she became curious about 'Who is this person sitting across from me?' and 'What are her experiences in the world as a lone parent living in poverty at the margins of society?' The author begins to think that she could shift from mere client investigation to pure wonderment about the Other by imagining herself as a researcher, an explorer of another's life world. Ultimately this process enables her to enhance the 'caring' in her practice with the knowledge gained of the perceptions and meanings impoverished clients assigned to their everyday lives. Jurgen Habermas' theory of communicative competence serves as the reference map guiding exploration. The author uses Habermas' theoretical principles of intersubjective mutuality--the validity claims of comprehensibility, truth, sincerity, and legitimacy. Comprehensibility embodies understanding, an attitude of unconditional acceptance, and care respect of another's individual person and self-defined reality. Intersubjective mutuality also requires that one dwell in the moment with the Other, satisfied that communication is founded on truth. Sincerity implies fostering the Other's expression of authentic self apart from oppressive distracters. Lastly, legitimacy reconciles the author's altruistic pursuit to know the Other's ontological truth with the reality of the present world.

  13. Calibration of sound velocimeter in pure water

    NASA Astrophysics Data System (ADS)

    Li, Zhiwei; Zhang, Baofeng; Li, Tao; Zhu, Junchao; Xie, Ziming

    2016-01-01

    Accurate measurement of sound speed is important to calibrate a sound velocity profiler which provides real-time sound velocity to the sonar equipment in oceanographic survey. The sound velocity profiler calculates the sound speed by measuring the time-of-flight of a 1 MHz single acoustic pulse to travel over about 300 mm path. A standard sound velocimeter instrument was invited to calibrate the sound velocity profiler in pure water at temperatures of 278,283, 288, 293, 298, 303 and 308K in a thermostatic vessel at one atmosphere. The sound velocity profiler was deployed in the thermostatic vessel alongside the standard sound velocimeter instrument and two platinum resistance thermometers (PRT) which were calibrated to 0.002k by comparison with a standard PRT. Time of flight circuit board was used to measure the time-of-flight to 22 picosecond precision. The sound speed which was measured by the sound velocity profiler was compared to the standard sound speed calculated by UNESCO to give the laboratory calibration coefficients and was demonstrated agreement with CTD-derived sound speed using Del Grosso's seawater equation after removing a bias.

  14. Localization of aerial pure tones by pinnipeds

    NASA Astrophysics Data System (ADS)

    Holt, Marla M.; Schusterman, Ronald J.; Kastak, David; Southall, Brandon L.

    2005-12-01

    In this study, minimum audible angles (MAAs) of aerial pure tones were measured in and compared between a northern elephant seal (Mirounga angustirostris), a harbor seal (Phoca vitulina), and a California sea lion (Zalophus californianus). Testing was conducted between 0.8 and 16 kHz in the elephant seal and 0.8 and 20 kHz in the harbor seal and sea lion in a hemi-anechoic chamber using a left/right psychophysical procedure. Performance for the same frequencies was also quantified for discrete speaker separation of 5° from the mid-line. For all subjects, MAAs ranged from approximately 3° to 15° and were generally equal to or larger than those previously measured in the same subjects with a broadband signal. Performance at 5° ranged from chance to 97% correct, depending on frequency and subject. Poorest performance in the sea lion and harbor seal occurred at intermediate frequencies, which is consistent with the duplex theory of sound localization. In contrast, the elephant seal's poorest performance occurred at higher frequencies. The elephant seal's result suggests an inferior ability to utilize interaural level differences and is perhaps related to best hearing sensitivity shifted toward lower frequencies in this species relative to other pinnipeds.

  15. Photoionization Dynamics in Pure Helium Droplets

    SciTech Connect

    Peterka, Darcy S.; Kim, Jeong Hyun; Wang, Chia C.; Poisson,Lionel; Neumark, Daniel M.

    2007-02-04

    The photoionization and photoelectron spectroscopy of pure He droplets are investigated at photon energies between 24.6 eV (the ionization energy of He) and 28 eV. Time-of-flight mass spectra and photoelectron images were obtained at a series of molecular beam source temperatures and pressures to assess the effect of droplet size on the photoionization dynamics. At source temperatures below 16 K, the photoelectron images are dominated by fast electrons produced via direct ionization of He atoms, with a small contribution from very slow electrons with kinetic energies below 1 meV arising from an indirect mechanism. The fast photoelectrons have as much as 0.5 eV more kinetic energy than those from atomic He at the same photon energy. This result is interpreted and simulated within the context of a 'dimer model', in which one assumes vertical ionization from two nearest neighbor He atoms to the attractive region of the He2+ potential energy curve. Possible mechanism for the slow electrons, which were also seen at energies below IE(He), are discussed, including vibrational autoionizaton of Rydberg states comprising an electron weakly bound to the surface of a large HeN+ core.

  16. TMED-4 INTERIM REPORT PURE ZR EQUILIBRIUM TEST RESULTS

    SciTech Connect

    Korinko, P.; Morgan, G.

    2010-12-17

    Due to higher than expected permeation rates in the production of tritium in the TVA, a development and testing program was implemented to develop the understanding of why the higher rates were occurring. In addition, improved data are needed for both the design as well as the predictive models. One part of the program was to determine the equilibrium pressure of hydrogen and tritium over NPZ (1). During the course of this testing, some curious results were discovered (2) compared to the published literature data (3). Due to these apparently results, a follow-on task was undertaken to determine the equilibrium pressure of protium and deuterium over pure zirconium. A series of experiments were conducted to determine equilibrium pressures and isotherm data for the zirconium - protium and zirconium - deuterium systems. The data match the published literature data reasonably well with the plateau extending to loadings of about 1.4. There is a significant pressure rise for loadings greater than 1.7.

  17. Pure tentorial subdural hematoma from rupture of aneurysm along the transmastoid branches of the occipital artery

    PubMed Central

    Nguyen, Ha Son; Doan, Ninh; Shabani, Saman; Gelsomino, Michael; Zaidat, Osama

    2016-01-01

    Background: Pure subdural hematoma (without subarachnoid, intraventricular, or intraparenchymal hemorrhage) due to a ruptured intracranial aneurysm is rare. Most reported cases involve an aneurysm along the internal carotid artery, posterior communicating artery, or middle cerebral artery. No reports have described an aneurysm along the transmastoid branches of the occipital artery. Case Description: A 70-year-old female presented with sudden-onset, excruciating headaches, associated with dizziness, nausea, and emesis. There was no history of trauma. Computed tomography (CT) head demonstrated a pure tentorial subdural hematoma. Vascular imaging revealed bilateral aneurysms along the transmastoid branches of the intracranial portion of both the occipital arteries. Consequently, these branches were embolized, with no residual filling of the aneurysms. After the procedure, the patient remained neurologically well. The patient was monitored appropriately for vasospasm, and was discharged home 10 days after presentation. Conclusion: Rupture of aneurysms along intracranial branches of the occipital artery can lead to pure subdural hematoma along the tentorium. PMID:27583173

  18. Pure-phase and pure-amplitude hologram design using the method of generalized projections

    NASA Astrophysics Data System (ADS)

    Catino, William Charles

    The overall contribution of the research presented in this dissertation is a systematic procedure for designing computer-generated holograms subject to far-field image constraints. The method of generalized projections is used to design pure-phase and pure-amplitude diffraction holograms that generate prescribed gray-scale images in the Fourier frequency plane. Performance is demonstrated with objective measures (error, efficiency, and variance), as well as with subjective comparison of images. Test images include a photographic quality image of Lena, a uniform intensity spot array, and a binary amplitude block text image. Projection algorithms are derived for pure-phase holograms with both continuous and quantized phase characteristics from a prescribed far-field magnitude constraint. The performance of the pure-phase hologram designs, as measured in the far-field image, is always very good for the continuous phase case and for the quantized phase case with a large number of phase quantization levels. However, as the number of quantization levels decreases, the performance typically degrades. Performance is significantly improved by constraining the energy in mutually exclusive cliques, that is, groups of image plane (far-field) pixels, instead of constraining the intensity of each individual pixel. Even for the binary phase case, acceptable images are generated with the clique energy algorithm. The method of generalized projections is also used to design pure-amplitude diffraction holograms using a prescribed image intensity constraint. Two algorithms are derived: the direct method, which nonlinearly constrains the hologram transmittance to the range of real values in (0,1); and the indirect method, which constrains the transmittance values to the real axis, and linearly transforms the resulting values to the range (0,1). Digital amplitude holograms are simulated by quantizing the amplitude holograms resulting from the indirect method. The indirect method

  19. Pure Java-based streaming MPEG player

    NASA Astrophysics Data System (ADS)

    Tolba, Osama; Briceno, Hector; McMillan, Leonard

    1999-01-01

    We present a pure Java-based streaming MPEG-1 video player. By implementing the player entirely in Java, we guarantee its functionality across platforms within any Java-enabled web browsers, without the need for native libraries. This allows greater sue of MPEG video sequences, because the users will no longer need to pre-install any software to display video, beyond Java compatibility. This player features a novel forward-mapping IDCT algorithm that allows it to play locally stored, CIF-sized video sequences at 11 frames per second, when run on a personal computer with Java 'just-in-time' compiler. The IDCT algorithm can run with greater speed when the sequence is viewed at reduced size; e.g., performing approximately 1/4 the amount of computation when the user resizes the sequence to 1/2 its original width and height. We are able to play video streams stored anywhere on the Internet with acceptable performance using a proxy server, eliminating the need for large-capacity auxiliary storage. Thus, the player is well suited to small devices, such as digital TV set-top decoders, requiring little more memory than is required for three video frames. Because of our modular design, it is possible to assemble multiple video streams from remote sources and present them simultaneously to the viewers, subject to network and local performance limitations. The same modular system can further provide viewers with their own customized view of each sessions; e.g., moving and resizing the video display window dynamically, and selecting their preferred set of video controls.

  20. Predictions of pure liquid shock Hugoniots

    SciTech Connect

    Hobbs, M.L.; Baer, M.R.

    1998-06-01

    Determination of product species and associated equations-of-state (EOS) for energetic materials such as pyrotechnics with complex elemental compositions remains a major unsolved problem. Although, empirical EOS models may be calibrated to replicate detonation conditions within experimental variability (5--10%), different states, e.g. expansion, may produce significant discrepancy with data if the basic form of the EOS model is incorrect. A more physically realistic EOS model based on intermolecular potentials, such as the Jacobs Cowperthwaite Zwisler (JCZ3) EOS, is needed to predict detonation states as well as expanded states. Predictive capability for any EOS requires a large species data base composed of a wide variety of elements. Unfortunately, only 20 species have known exponential 6 (EXP 6) molecular force constants which are used in the JCZ3-EOS. Of these 20 species, only 10 have been adequately compared to experimental data such as molecular scattering or shock Hugoniot data. Since data in the strongly repulsive region of the molecular potential is limited, alternative methods must be found to deduce force constants for a larger number of species. The objective of the present study is to determine JCZ3 product species force constants using corresponding state theory. Intermolecular potential parameters were obtained for a variety of gas species using a simple corresponding states technique with critical volume and critical temperature. A more complex, four parameter corresponding state method with shape and polarity corrections was also used to obtain intermolecular potential parameters. Both corresponding state methods were used to predict shock Hugoniot data obtained from pure liquids. The simple corresponding state method is shown to give adequate agreement with shock Hugoniot data.

  1. Metabolism of phenolic compounds by Lactobacillus spp. during fermentation of cherry juice and broccoli puree.

    PubMed

    Filannino, Pasquale; Bai, Yunpeng; Di Cagno, Raffaela; Gobbetti, Marco; Gänzle, Michael G

    2015-04-01

    This study aimed to investigate the metabolism of phenolic acids and flavonoids during lactic acid fermentation of cherry juice and broccoli puree for potential food and pharmaceutical purposes. When fermenting cherry juice and broccoli puree, Lactobacillus spp. exhibited strain-specific metabolism of phenolic acid derivatives. The metabolism of protocatechuic, caffeic and p-coumaric acids through phenolic acid decarboxylases and reductases differed between mMRS and cherry juice and broccoli puree. The synthesis of reduced compounds was the highest during food fermentations and the substrate seemed to modulate the metabolism of phenolic compounds. The reduction of phenolic acids involves a hydrogen donor and the re-oxidation of the reduced co-factor NADH, which may provide a metabolic advantage through NAD(+) regeneration. Quinic acid reduction may replace fructose and pyruvate as hydrogen acceptors, and it may provide an energetic advantage to heterofermentative bacteria when growing in broccoli puree lacking of fructose. This study demonstrated that phenolics metabolism may confer a selective advantage for lactobacilli in vegetable and fruit fermentation, and the metabolic routes are strongly dependent on the intrinsic factors of substrate. Fermented cherry juice and broccoli puree, due to the selected bacterial bioconversion pathways, are enriched in phenolic derivative with high human bioavailability and biological activity.

  2. Entanglement bound for multipartite pure states based on local measurements

    SciTech Connect

    Jiang Lizhen; Chen Xiaoyu; Ye Tianyu

    2011-10-15

    An entanglement bound based on local measurements is introduced for multipartite pure states. It is the upper bound of the geometric measure and the relative entropy of entanglement. It is the lower bound of the minimal-measurement entropy. For pure bipartite states, the bound is equal to the entanglement entropy. The bound is applied to pure tripartite qubit states and the exact tripartite relative entropy of entanglement is obtained for a wide class of states.

  3. Typical pure nonequilibrium steady states and irreversibility for quantum transport.

    PubMed

    Monnai, Takaaki; Yuasa, Kazuya

    2016-07-01

    It is known that each single typical pure state in an energy shell of a large isolated quantum system well represents a thermal equilibrium state of the system. We show that such typicality holds also for nonequilibrium steady states (NESS's). We consider a small quantum system coupled to multiple infinite reservoirs. In the long run, the total system reaches a unique NESS. We identify a large Hilbert space from which pure states of the system are to be sampled randomly and show that the typical pure states well describe the NESS. We also point out that the irreversible relaxation to the unique NESS is important to the typicality of the pure NESS's.

  4. Typical pure nonequilibrium steady states and irreversibility for quantum transport

    NASA Astrophysics Data System (ADS)

    Monnai, Takaaki; Yuasa, Kazuya

    2016-07-01

    It is known that each single typical pure state in an energy shell of a large isolated quantum system well represents a thermal equilibrium state of the system. We show that such typicality holds also for nonequilibrium steady states (NESS's). We consider a small quantum system coupled to multiple infinite reservoirs. In the long run, the total system reaches a unique NESS. We identify a large Hilbert space from which pure states of the system are to be sampled randomly and show that the typical pure states well describe the NESS. We also point out that the irreversible relaxation to the unique NESS is important to the typicality of the pure NESS's.

  5. Efficient decomposition of cosmic microwave background polarization maps into pure E, pure B, and ambiguous components

    SciTech Connect

    Bunn, Emory F.

    2011-04-15

    Separation of the B component of a cosmic microwave background (CMB) polarization map from the much larger E component is an essential step in CMB polarimetry. For a map with incomplete sky coverage, this separation is necessarily hampered by the presence of ambiguous modes which could be either E or B modes. I present an efficient pixel-space algorithm for removing the ambiguous modes and separating the map into pure E and B components. The method, which works for arbitrary geometries, does not involve generating a complete basis of such modes and scales the cube of the number of pixels on the boundary of the map.

  6. 1. SOUTH AND WEST ELEVATION OF ILLINOIS PURE ALUMINUM (IPA) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. SOUTH AND WEST ELEVATION OF ILLINOIS PURE ALUMINUM (IPA) COMPANY FACTORY; SOUTH ELEVATION FACING ILLINOIS CENTRAL GULF RAILROAD TRACKS AND MAIN STREET. THE ONE-STORY BRICK BUILDING TO THE LEFT IS AN ABANDONED COMMONWEALTH EDISON COMPANY ELECTRICAL SUBSTATION. - Illinois Pure Aluminum Company, 109 Holmes Street, Lemont, Cook County, IL

  7. Physical and Spiritual Education within the Framework of Pure Life

    ERIC Educational Resources Information Center

    Bagheri Noaparast, Khosrow

    2013-01-01

    This paper aims at showing the dimensions of spirituality in childhood education by suggesting a new analysis of the concept of "pure life" used in the Qur'an. Putting spirituality in the framework of the pure life provides us with a rich framework in dealing with spirituality as the latter will be extended to all dimensions of a life. In the…

  8. Pure Lymphoepithelioma-Like Carcinoma Originating from the Urinary Bladder

    PubMed Central

    Nagai, Takashi; Naiki, Taku; Kawai, Noriyasu; Iida, Keitaro; Etani, Toshiki; Ando, Ryosuke; Hamamoto, Shuzo; Sugiyama, Yosuke; Okada, Atsushi; Mizuno, Kentaro; Umemoto, Yukihiro; Yasui, Takahiro

    2016-01-01

    Lymphoepithelioma-like carcinoma of the urinary bladder (LELCB) is a rare variant of infiltrating urothelial carcinoma. We report a case of LELCB in a 43-year-old man. Ultrasonography and cystoscopy revealed two bladder tumors, one on the left side of the trigone and the other on the right side of the trigone. Transurethral resection of the bladder tumors was performed and pathological analysis revealed undifferentiated carcinoma. We therefore performed radical cystectomy and urinary diversion. Immunohistochemically the tumor cells were positive for cytokeratin, but negative for Epstein-Barr virus-encoded small RNA in situ hybridization as found for previous cases of LELCB. The final pathological diagnosis was a lymphoepithelioma-like variant of urothelial carcinoma with perivesical soft tissue invasion. For adjuvant systemic chemotherapy, three courses of cisplatin were administered. The patient subsequently became free of cancer 72 months postoperatively. Based on the literature, pure or predominant LELCB types show favorable prognoses due to their sensitivity to chemotherapy or radiotherapy. An analysis of the apparent diffusion coefficient (ADC) values of bladder tumors examined in our institution revealed that the ADC value measured for this LELCB was relatively low compared to conventional urothelial carcinomas. This suggests that measuring the ADC value of a lymphoepithelioma-like carcinoma prior to operation may be helpful in predicting LELCB. PMID:27099604

  9. Temperature dependent deformation mechanisms in pure amorphous silicon

    SciTech Connect

    Kiran, M. S. R. N. Haberl, B.; Williams, J. S.; Bradby, J. E.

    2014-03-21

    High temperature nanoindentation has been performed on pure ion-implanted amorphous silicon (unrelaxed a-Si) and structurally relaxed a-Si to investigate the temperature dependence of mechanical deformation, including pressure-induced phase transformations. Along with the indentation load-depth curves, ex situ measurements such as Raman micro-spectroscopy and cross-sectional transmission electron microscopy analysis on the residual indents reveal the mode of deformation under the indenter. While unrelaxed a-Si deforms entirely via plastic flow up to 200 °C, a clear transition in the mode of deformation is observed in relaxed a-Si with increasing temperature. Up to 100 °C, pressure-induced phase transformation and the observation of either crystalline (r8/bc8) end phases or pressure-induced a-Si occurs in relaxed a-Si. However, with further increase of temperature, plastic flow rather than phase transformation is the dominant mode of deformation. It is believed that the elevated temperature and pressure together induce bond softening and “defect” formation in structurally relaxed a-Si, leading to the inhibition of phase transformation due to pressure-releasing plastic flow under the indenter.

  10. Interfacial oxidations of pure titanium and titanium alloys with investments.

    PubMed

    Ban, S; Watanabe, T; Mizutani, N; Fukui, H; Hasegawa, J; Nakamura, H

    2000-12-01

    External oxides of a commercially pure titanium (cpTi), Ti6Al4V alloy, and an experimental beta-type titanium alloy (Ti 53.4 wt%, Nb 29 wt%, Ta 13 wt%, and Zr 4.6 wt%) were characterized after heating to 600, 900, 1150, and 1400 degrees C in contact with three types of investments (alumina cement, magnesia cement, and phosphate-bonded) in air. XRD studies demonstrated that MgO, Li2TiO3 and/or Li2Ti3O7 were formed through reactions with the metal and the constituents in the magnesia cement-investment after heating to 900, 1150, and 1400 degrees C. Except for these conditions, TiO2 (rutile) was only formed on cpTi. For titanium alloys, the other components apart from Ti also formed simple and complex oxides such as Al2O3 and Al2TiO5 on Ti6Al4V, and Zr0.25Ti0.75Nb2O7 on the beta-type titanium alloy. However, no oxides containing V or Ta were formed. These results suggest that the constituents of titanium alloys reacted with the investment oxides and atmospheric oxygen to form external oxides due to the free energy of oxide formation and the concentration of each element on the metal surface.

  11. Early stages during plasma nitriding of pure iron

    SciTech Connect

    Palacios, M.D.; Martinez, O.; Oseguera, J.

    1995-12-31

    The sequence of nitride formation during the early stages of plasma nitriding of pure iron was studied by optical microscopy, SEM, TEM and x-ray diffraction. Plasma nitriding at {approximately}490 C in a 25 vol.%H{sub 2} + 75 vol.%N{sub 2} mixture starts with the formation of {gamma}{prime}-Fe{sub 4}N after 40s. Once {gamma}{prime} nucleates, it mainly spreads laterally due to diffusion shortcuts in the discontinuous surface nitride layer. Before {gamma}{prime} is continuous on the surface, {epsilon} nucleates on top of it shortly after 40S. Epsilon is then observed to grow, both inwardly and laterally along with {gamma}{prime}. A compact {gamma}{prime}/{epsilon} bilayer forms on the surface at around 100s. The kinetics of nucleation, growth and compactation of the nitrides observed in the present work was significantly more rapid than in any of the nitriding process reported in the literature, including plasma nitriding. The acceleration of the nitriding kinetics in the early stages of plasma nitriding may be attributed to enhanced diffusion resulting from a high nitrogen flux from the plasma atmosphere. The results presented are consistent with the findings of a companion work on modeling the kinetics of nitride layer growth.

  12. Diffusion bonding of commercially pure Ni using Cu interlayer

    SciTech Connect

    Rahman, A.H.M.E. Cavalli, M.N.

    2012-07-15

    The concentration dependence of diffusivity in a multi-component diffusion system makes it complicated to predict the concentration profiles of diffusing species. This so called chemical diffusivity can be expressed as a function of thermodynamic and kinetic data. DICTRA software can calculate the concentration profiles using appropriate mobility and thermodynamic data. It can also optimize the diffusivity data using experimental diffusivity data. Then the optimized diffusivity data is stored as mobility data which is a linear function of temperature. In this work, diffusion bonding of commercially pure Ni using Cu interlayers is reported. The mobility parameters of Ni-Cu alloy binary systems were optimized using DICTRA/Thermocalc software from the available self-, tracer and chemical diffusion coefficients. The optimized mobility parameters were used to simulate concentration profiles of Ni-Cu diffusion joints using DICTRA/Thermocalc software. The calculated and experimental concentration profiles agreed well at 1100 Degree-Sign C. Agreement between the simulated and experimental profiles was less good at 1050 Degree-Sign C due to the grain boundary contribution to the overall diffusion. - Highlights: Black-Right-Pointing-Pointer The concentration profiles of Cu in Ni-Cu diffusion joints are modeled. Black-Right-Pointing-Pointer Interdiffusion coefficients in Ni-Cu system are optimized. Black-Right-Pointing-Pointer Optimized interdiffusion coefficients are expressed as mobility parameters. Black-Right-Pointing-Pointer Simulated profiles are comparable with experimental profiles.

  13. Fabrication of Ultralow Density Interconnected Pure Metal Foams

    NASA Astrophysics Data System (ADS)

    Burks, Edward C.; Gilbert, Dustin A.; Liu, Kai; Kucheyev, Sergei O.; Colvin, Jeffrey D.; Felter, Thomas E.

    Ultra-low density metallic nanostructures have been shown to possess interesting thermal, electrical, magnetic, chemical and mechanical properties due to their extremely high surface areas, nanoscale geometries and high porosities. Here we report the synthesis of pure metal foams using interconnected metallic nanowires with densities as low as 0.1% of their bulk density that are still mechanically stable. The highly porous monoliths are macroscopic in size (several mm) and can be created in a wide variety of shapes for application-specific needs. Preliminary studies of such metal foams have already revealed fascinating mechanical and magnetic properties, since the physical dimensions of the foams are below some of the basic length scales that govern the material properties. These foams have been used as targets for ultrabright x-ray sources. They also have a wide variety of other potential applications such as photovoltaic devices, supercapacitors, catalysts, coatings, fuel cells, etc. This work has been supported by DTRA #BRCALL08-Per3-C-2-0006, and in part by NSF DMR-1008791 and DMR-1543582. Work at LLNL was performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344.

  14. Automated Speech Rate Measurement in Dysarthria

    ERIC Educational Resources Information Center

    Martens, Heidi; Dekens, Tomas; Van Nuffelen, Gwen; Latacz, Lukas; Verhelst, Werner; De Bodt, Marc

    2015-01-01

    Purpose: In this study, a new algorithm for automated determination of speech rate (SR) in dysarthric speech is evaluated. We investigated how reliably the algorithm calculates the SR of dysarthric speech samples when compared with calculation performed by speech-language pathologists. Method: The new algorithm was trained and tested using Dutch…

  15. Optical absorption coefficients of pure water

    NASA Astrophysics Data System (ADS)

    Lu, Zheng; Zhao, Xianzhen; Fry, Edward S.

    2002-10-01

    The integrating cavity absorption meter(ICAM), which is independent of scattering effect, is used to measure the absolute values of small optical absorption coefficients of liquid. A modified ICAM is being used to measure the absorption of water in the wavelength range 300 to 700 nm. The ultrapure water produced by a two-stages water purification system reaches Type I quality. This is equal to or better than ASTM,CAP and NCCLS water quality standards. To avoid the fact that dissolved oxygen absorbs ultraviolet light due to the photochemical effect, the water sample is delivered through a nitrogen sealed system which will prevent the sample from contacting with oxygen. A compassion of our absorption spectrum with other existing data is given.

  16. Short time cycles of purely quantum refrigerators

    NASA Astrophysics Data System (ADS)

    Feldmann, Tova; Kosloff, Ronnie

    2012-05-01

    Four stroke Otto refrigerator cycles with no classical analog are studied. Extremely short cycle times with respect to the internal timescale of the working medium characterize these refrigerators. Therefore, these cycles are termed sudden. The sudden cycles are characterized by the stable limit cycle, which is the invariant of the global cycle propagator. During their operation the states of the working medium possess significant coherence which is not erased in the equilibration segments due to the very short time allocated. This characteristic is reflected in a difference between the energy entropy and the Von Neumann entropy of the working medium. A classification scheme for sudden refrigerators is developed allowing simple approximations for the cooling power and coefficient of performance.

  17. Quick re-introduction of selective scalar interactions in a pure-shift NMR spectrum.

    PubMed

    Lokesh, N; Chaudhari, Sachin Rama; Suryaprakash, N

    2014-12-21

    A new 1D NMR experiment cited as 'Quick G-SERF', which re-introduces selective proton-proton scalar interactions in a pure shift spectrum during real time data acquisition, is reported. The method provides information on multiple proton-proton couplings from a single experiment, analogous to the 2D G-SERF technique, while significantly shortening the experimental time by 1-2 orders of magnitude due to reduced dimension and enhanced sensitivity.

  18. Buffer-regulated biocorrosion of pure magnesium.

    PubMed

    Kirkland, Nicholas T; Waterman, Jay; Birbilis, Nick; Dias, George; Woodfield, Tim B F; Hartshorn, Richard M; Staiger, Mark P

    2012-02-01

    Magnesium (Mg) alloys are being actively investigated as potential load-bearing orthopaedic implant materials due to their biodegradability in vivo. With Mg biomaterials at an early stage in their development, the screening of alloy compositions for their biodegradation rate, and hence biocompatibility, is reliant on cost-effective in vitro methods. The use of a buffer to control pH during in vitro biodegradation is recognised as critically important as this seeks to mimic pH control as it occurs naturally in vivo. The two different types of in vitro buffer system available are based on either (i) zwitterionic organic compounds or (ii) carbonate buffers within a partial-CO(2) atmosphere. This study investigated the influence of the buffering system itself on the in vitro corrosion of Mg. It was found that the less realistic zwitterion-based buffer did not form the same corrosion layers as the carbonate buffer, and was potentially affecting the behaviour of the hydrated oxide layer that forms on Mg in all aqueous environments. Consequently it was recommended that Mg in vitro experiments use the more biorealistic carbonate buffering system when possible.

  19. Photonuclear activation of pure isotopic mediums.

    SciTech Connect

    Grohman, Mark A.; Lukosi, Eric Daniel

    2010-06-01

    This work simulated the response of idealized isotopic U-235, U-238, Th-232, and Pu-239 mediums to photonuclear activation with various photon energies. These simulations were conducted using MCNPX version 2.6.0. It was found that photon energies between 14-16 MeV produce the highest response with respect to neutron production rates from all photonuclear reactions. In all cases, Pu-239 responds the highest, followed by U-238. Th-232 produces more overall neutrons at lower photon energies then U-235 when material thickness is above 3.943 centimeters. The time it takes each isotopic material to reach stable neutron production rates in time is directly proportional to the material thickness and stopping power of the medium, where thicker mediums take longer to reach stable neutron production rates and thinner media display a neutron production plateau effect, due to the lack of significant attenuation of the activating photons in the isotopic mediums. At this time, no neutron sensor system has time resolutions capable of verifying these simulations, but various indirect methods are possible and should be explored for verification of these results.

  20. THE PREPARATION OF RELATIVELY PURE BACTERIOPHAGE.

    PubMed

    Krueger, A P; Tamada, H T

    1929-11-20

    The method described above, based on the electrophoretic migration of bacteriophage particles into an agar gel and their subsequent re-suspension in a suitable medium, has the following advantages: It is simple and can be readily carried out on a comparatively large scale by merely inserting additional units between the same electrode cups. It requires but one extraction and the resulting phage suspension is strongly lytic, an average sample being capable of completely lysing susceptible bacteria at a dilution of 10(-16). The suspension contains no proteins demonstrable by the biuret, alcohol, xanthoproteic, Millon or Hopkins-Cole reactions and yields but 0.044 mg. N/cc. directly attributable to the phage. Each corpuscle contains no more nitrogen than a single molecule of protein. In addition the method is applicable to determinations of the electric charge carried by biologically active substances of small dimensions, e.g., phage, toxins, and perhaps some viruses. It offers as well a possible means of purification of these substances. The purified bacteriophage obtained by such a procedure or similar ones is relatively unstable. Work now in progress indicates that it does not possess nearly the resistance to chemical agents, drying, etc., that non-purified phage displays. It is suggested that experiments designed to test the therapeutic value of bacteriophage be conducted, when possible, with purified suspensions thereby avoiding any possibility of obscure non-specific reactions due to other constituents of the lysates.

  1. Differentiating Profiles of Speech Impairments in Friedreich's Ataxia: A Perceptual and Instrumental Approach

    ERIC Educational Resources Information Center

    Folker, Joanne E.; Murdoch, Bruce E.; Rosen, Kristin M.; Cahill, Louise M.; Delatycki, Martin B.; Corben, Louise A.; Vogel, Adam P.

    2012-01-01

    Background: The speech disorder associated with Friedreich's ataxia (FRDA) is classically described as ataxic dysarthria. However, variable neuropathology beyond the cerebellum, which may include the corticospinal and corticobulbar tracts, means that the dysarthria can be mixed rather than a pure ataxic dysarthria. Aims: To characterize…

  2. Generation and detection of pure valley current by electrically induced Berry curvature in bilayer graphene

    NASA Astrophysics Data System (ADS)

    Shimazaki, Y.; Yamamoto, M.; Borzenets, I. V.; Watanabe, K.; Taniguchi, T.; Tarucha, S.

    2015-12-01

    The field of `Valleytronics’ has recently been attracting growing interest as a promising concept for the next generation electronics, because non-dissipative pure valley currents with no accompanying net charge flow can be manipulated for computational use, akin to pure spin currents. Valley is a quantum number defined in an electronic system whose energy bands contain energetically degenerate but non-equivalent local minima (conduction band) or maxima (valence band) due to a certain crystal structure. Specifically, spatial inversion symmetry broken two-dimensional honeycomb lattice systems exhibiting Berry curvature is a subset of possible systems that enable optical, magnetic and electrical control of the valley degree of freedom. Here we use dual-gated bilayer graphene to electrically induce and control broken inversion symmetry (or Berry curvature) as well as the carrier density for generating and detecting the pure valley current. In the insulating regime, at zero-magnetic field, we observe a large nonlocal resistance that scales cubically with the local resistivity, which is evidence of pure valley current.

  3. Shunting arc plasma source for pure carbon ion beam.

    PubMed

    Koguchi, H; Sakakita, H; Kiyama, S; Shimada, T; Sato, Y; Hirano, Y

    2012-02-01

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA∕mm(2) at the peak of the pulse.

  4. Shunting arc plasma source for pure carbon ion beama)

    NASA Astrophysics Data System (ADS)

    Koguchi, H.; Sakakita, H.; Kiyama, S.; Shimada, T.; Sato, Y.; Hirano, Y.

    2012-02-01

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA/mm2 at the peak of the pulse.

  5. Pure-state informationally complete and 'really' complete measurements

    SciTech Connect

    Finkelstein, J.

    2004-11-01

    I construct a positive-operator-valued measure (POVM) which has 2d rank-1 elements and which is informationally complete for generic pure states in d dimensions, thus confirming a conjecture made by Flammia, Silberfarb, and Caves (e-print quant-ph/0404137). I show that if a rank-1 POVM is required to be informationally complete for all pure states in d dimensions, it must have at least 3d-2 elements. I also show that, in a POVM which is informationally complete for all pure states in d dimensions, for any vector there must be at least 2d-1 POVM elements which do not annihilate that vector.

  6. Pure midbrain ischemia and hypoplastic vertebrobasilar circulation.

    PubMed

    Gilberti, Nicola; Gamba, Massimo; Costa, Angelo; Vergani, Veronica; Spezi, Raffaella; Pezzini, Alessandro; Volonghi, Irene; Mardighian, Dikran; Gasparotti, Roberto; Padovani, Alessandro; Magoni, Mauro

    2014-02-01

    Isolated midbrain infarction is rare and little is known about etiology and patient's long-term follow up. We aimed to describe the clinical features, the causative diseases and the outcome of patients with isolated midbrain infarction who were admitted to our center, focusing on vascular abnormalities of posterior circulation. All patients with first acute ischemic stroke limited to the midbrain were included and their demographic features, neurological symptoms, neuroimaging data, and cardiovascular risk factors were recorded. Functional outcome, using modified Rankin scale, was assessed at discharge and at the 3 month follow up evaluation. We found nine patients with acute isolated midbrain infarction, representing 0.61 % of all ischemic stroke admitted to our center. The most common cause of stroke was small-vessel disease (88.8 %). At stroke onset, none of the patients had consciousness disturbances, and four patients (44.4 %) had gait impairment, five patients (55.5 %) presented with diplopia due to involvement of the third nerve or fascicular type of third-nerve palsy, seven patients (77.7 %) had vascular anomalies of vertebrobasilar circulation: the most frequent was vertebral artery hypoplasia [four patients (44.4 %)]. At follow up evaluation, seven patients (77.7 %) had a good functional outcome and no patients experienced recurrence of cerebrovascular events. As isolated midbrain infarction is uncommon, specific ocular motor signs, mainly third-nerve palsy, may help to identify and localize the mesencephalic infarct. Abnormalities in vertebrobasilar circulation, such as hypoplastic basilar or vertebral artery, are frequently associated with isolated midbrain ischemia. The hypoplastic vertebrobasilar system may predispose to posterior ischemic stroke.

  7. Human due diligence.

    PubMed

    Harding, David; Rouse, Ted

    2007-04-01

    Most companies do a thorough job of financial due diligence when they acquire other companies. But all too often, deal makers simply ignore or underestimate the significance of people issues in mergers and acquisitions. The consequences are severe. Most obviously, there's a high degree of talent loss after a deal's announcement. To make matters worse, differences in decision-making styles lead to infighting; integration stalls; and productivity declines. The good news is that human due diligence can help companies avoid these problems. Done early enough, it helps acquirers decide whether to embrace or kill a deal and determine the price they are willing to pay. It also lays the groundwork for smooth integration. When acquirers have done their homework, they can uncover capability gaps, points of friction, and differences in decision making. Even more important, they can make the critical "people" decisions-who stays, who goes, who runs the combined business, what to do with the rank and file-at the time the deal is announced or shortly thereafter. Making such decisions within the first 30 days is critical to the success of a deal. Hostile situations clearly make things more difficult, but companies can and must still do a certain amount of human due diligence to reduce the inevitable fallout from the acquisition process and smooth the integration. This article details the steps involved in conducting human due diligence. The approach is structured around answering five basic questions: Who is the cultural acquirer? What kind of organization do you want? Will the two cultures mesh? Who are the people you most want to retain? And how will rank-and-file employees react to the deal? Unless an acquiring company has answered these questions to its satisfaction, the acquisition it is making will be very likely to end badly.

  8. Faster and cleaner real-time pure shift NMR experiments

    NASA Astrophysics Data System (ADS)

    Mauhart, Johannes; Glanzer, Simon; Sakhaii, Peyman; Bermel, Wolfgang; Zangger, Klaus

    2015-10-01

    Real-time pure shift experiments provide highly resolved proton NMR spectra which do not require any special processing. Although being more sensitive than their pseudo 2D counterparts, their signal intensities per unit time are still far below regular NMR spectra. In addition, scalar coupling evolution during the individual data chunks produces decoupling sidebands. Here we show that faster and cleaner real-time pure shift spectra can be obtained through the implementation of two parameter alterations. Variation of the FID chunk lengths between individual transients significantly suppresses decoupling sidebands for any kind of real-time pure shift spectra and thus allows for example the analysis of minor components in compound mixtures. Shifting the excitation frequency between individual scans of real-time slice-selective pure shift spectra increases their sensitivity obtainable in unit time by allowing faster repetitions of acquisitions.

  9. [Neurolinguistic analysis of a case of pure agraphia].

    PubMed

    Petrillo, S; Poli, R; Piccirilli, M

    1990-01-01

    A patient with a pure acquired dysgraphia is reported. The pattern of the patient's performance is discussed in relation to current functional models of writing. The case may be interpreted by assuming a selective impairment to the graphemic buffer.

  10. Typical pure nonequilibrium steady states and irreversibility for quantum transport.

    PubMed

    Monnai, Takaaki; Yuasa, Kazuya

    2016-07-01

    It is known that each single typical pure state in an energy shell of a large isolated quantum system well represents a thermal equilibrium state of the system. We show that such typicality holds also for nonequilibrium steady states (NESS's). We consider a small quantum system coupled to multiple infinite reservoirs. In the long run, the total system reaches a unique NESS. We identify a large Hilbert space from which pure states of the system are to be sampled randomly and show that the typical pure states well describe the NESS. We also point out that the irreversible relaxation to the unique NESS is important to the typicality of the pure NESS's. PMID:27575115

  11. The effect of pure state structure on nonequilibrium dynamics

    NASA Astrophysics Data System (ADS)

    Newman, C. M.; Stein, D. L.

    2008-06-01

    Motivated by short-range Ising spin glasses, we review some rigorous results and their consequences for the relation between the number/nature of equilibrium pure states and nonequilibrium dynamics. Two of the consequences for spin glass dynamics following an instantaneous deep quench to a temperature with broken spin flip symmetry are: (1) almost all initial configurations lie on the boundary between the basins of attraction of multiple pure states; (2) unless there are uncountably many pure states with almost all pairs having zero overlap, there can be no equilibration to a pure state as time t \\to \\infty . We discuss the relevance of these results to the difficulty of equilibration of spin glasses. We also review some results concerning the 'nature versus nurture' problem of whether the large-t behavior of both ferromagnets and spin glasses following a deep quench is determined more by the initial configuration (nature) or by the dynamics realization (nurture).

  12. Acquired pure megakaryocytic aplasia successfully treated with cyclosporine.

    PubMed

    Omri, Halima El; Ibrahim, Firyal; Taha, Ruba Yasin; Negm, Riham Hassan; Khinji, Aisha Al; Yassin, Mohammed; Hijji, Ibrahim Al; Ayoubi, Hanadi El; Baden, Hussein

    2010-12-01

    Acquired pure megakaryocytic aplasia is a rare hematological disorder characterized by thrombocytopenia with absent or markedly reduced megakaryocytes in the bone marrow. We report a case of a 25-year-old male diagnosed as acquired pure megakaryocytic aplasia. Treatment with prednisone and intravenous immunoglobulin failed, but he was successfully treated with cyclosporine, with complete remission after 90 days and normal platelet count maintained thereafter. PMID:27263744

  13. Adiabatic expansion of a strongly correlated pure electron plasma

    SciTech Connect

    Dubin, D.H.E.; O'Neil, T.M.

    1986-02-17

    Adiabatic expansion is proposed as a method of increasing the degree of correlation of a magnetically confined pure electron plasma. Quantum mechanical effects and correlation effects make the physics of the expansion quite different from that for a classical ideal gas. The proposed expansion may be useful in a current experimental effort to cool a pure electron plasma to the liquid and solid (crystalline) states.

  14. Adiabatic expansion of a strongly correlated pure electron plasma

    NASA Astrophysics Data System (ADS)

    Dubin, D. H. E.; Oneil, T. M.

    1986-02-01

    Adiabatic expansion is proposed as a method of increasing the degree of correlation of a magnetically confined pure electron plasma. Quantum mechanical effects and correlation effects make the physics of the expansion quite different from that for a classical ideal gas. The proposed expansion may be useful in a current experimental effort to cool a pure electron plasma to the liquid and solid (crystalline) states.

  15. Hybrids, pure cultures, and pure lines: from nineteenth-century biology to twentieth-century genetics.

    PubMed

    Müller-Wille, Staffan

    2007-12-01

    Prompted by recent recognitions of the omnipresence of horizontal gene transfer among microbial species and the associated emphasis on exchange, rather than isolation, as the driving force of evolution, this essay will reflect on hybridization as one of the central concerns of nineteenth-century biology. I will argue that an emphasis on horizontal exchange was already endorsed by 'biology' when it came into being around 1800 and was brought to full fruition with the emergence of genetics in 1900. The true revolution in nineteenth-century life sciences, I maintain, consisted in a fundamental shift in ontology, which eroded the boundaries between individual and species, and allowed biologists to move up and down the scale of organic complexity. Life became a property extending both 'downwards', to the parts that organisms were composed of, as well as 'upwards', to the collective entities constituted by the relations of exchange and interaction that organisms engage in to reproduce. This mode of thinking was crystallized by Gregor Mendel and consolidated in the late nineteenth-century conjunction of biochemistry, microbiology and breeding in agro-industrial settings. This conjunction and its implications are especially exemplified by Wilhelm Johannsen's and Martinus Beijerinck's work on pure lines and cultures. An understanding of the subsequent constraints imposed by the evolutionary synthesis of the twentieth century on models of genetic systems may require us to rethink the history of biology and displace Darwin's theory of natural selection from that history's centre. PMID:18053934

  16. Pure-tone birdsong by resonance filtering of harmonic overtones

    PubMed Central

    Beckers, Gabriël J. L.; Suthers, Roderick A.; Cate, Carel ten

    2003-01-01

    Pure-tone song is a common and widespread phenomenon in birds. The mechanistic origin of this type of phonation has been the subject of long-standing discussion. Currently, there are three hypotheses. (i) A vibrating valve in the avian vocal organ, the syrinx, generates a multifrequency harmonic source sound, which is filtered to a pure tone by a vocal tract filter (“source-filter” model, analogous to human speech production). (ii) Vocal tract resonances couple with a vibrating valve source, suppressing the normal production of harmonic overtones at this source (“soprano” model, analogous to human soprano singing). (iii) Pure-tone sound is produced as such by a sound-generating mechanism that is fundamentally different from a vibrating valve. Here we present direct evidence of a source-filter mechanism in the production of pure-tone birdsong. Using tracheal thermistors and air sac pressure cannulae, we recorded sound signals close to the syringeal sound source during spontaneous, pure-tone vocalizations of two species of turtledove. The results show that pure-tone dove vocalizations originate through filtering of a multifrequency harmonic sound source. PMID:12764226

  17. Preserving Ultra-Pure Uranium-233

    SciTech Connect

    Krichinsky, Alan M; Goldberg, Dr. Steven A.; Hutcheon, Dr. Ian D.

    2011-10-01

    Uranium-233 ({sup 233}U) is a synthetic isotope of uranium formed under reactor conditions during neutron capture by natural thorium ({sup 232}Th). At high purities, this synthetic isotope serves as a crucial reference material for accurately quantifying and characterizing uranium-bearing materials assays and isotopic distributions for domestic and international nuclear safeguards. Separated, high purity {sup 233}U is stored in vaults at Oak Ridge National Laboratory (ORNL). These materials represent a broad spectrum of {sup 233}U from the standpoint of isotopic purity - the purest being crucial for precise analyses in safeguarding uranium. All {sup 233}U at ORNL is currently scheduled to be disposed of by down-blending with depleted uranium beginning in 2015. This will reduce safety concerns and security costs associated with storage. Down-blending this material will permanently destroy its potential value as a certified reference material for use in uranium analyses. Furthermore, no credible options exist for replacing {sup 233}U due to the lack of operating production capability and the high cost of restarting currently shut down capabilities. A study was commissioned to determine the need for preserving high-purity {sup 233}U. This study looked at the current supply and the historical and continuing domestic need for this crucial isotope. It examined the gap in supplies and uses to meet domestic needs and extrapolated them in the context of international safeguards and security activities - superimposed on the recognition that existing supplies are being depleted while candidate replacement material is being prepared for disposal. This study found that the total worldwide need by this projection is at least 850 g of certified {sup 233}U reference material over the next 50 years. This amount also includes a strategic reserve. To meet this need, 18 individual items totaling 959 g of {sup 233}U were identified as candidates for establishing a lasting supply of

  18. Preparation of ultra-pure water and acids and investigation of background of an ICP-MS laboratory.

    PubMed

    Yuan, H; Hu, S; Tong, J; Zhao, L; Lin, S; Gao, S

    2000-09-01

    Ultra-pure water is prepared by distillation, and followed by ion exchange and passing through an E-PURE water purifier. The resulting ultra-pure water has an electrical conductivity of 18 MOmega. Ultra-pure nitric, hydrochloric, hydrofluoric and perchloric acids are prepared by sub-boiling distillation. Spectra for mass range 3-240 amu are scanned by inductively coupled plasma mass spectrometry for tap, distilled, deionized and ultra-pure waters, and extra- and ultra-pure acids. The results show that the sub-boiling distillation greatly improves the quality of all the four acids under investigation. Metal impurities such as 75, 93, 121, 123, 134-138, 181 and 206-209 amu were remarkably reduced (sub-ppb level) after sub-boiling distillation. Configuration of peaks due to the formation of polyatomic ions was similar to the literature values reported elsewhere (S.H. Tan, G. Horlick, Appl. Spectrosc. 40 (4) (1986) 445). PMID:18968057

  19. Solid-state characterization of optically pure (+)Dihydromyricetin extracted from Ampelopsis grossedentata leaves.

    PubMed

    Wang, Chenguang; Xiong, Wei; Reddy Perumalla, Sathyanarayana; Fang, Jianguo; Calvin Sun, Changquan

    2016-09-10

    Dihydromyricetin (DMY) is a natural flavanol compound isolated from a traditional Chinese medicine, Ampelopsis grossedentata. Despite that optically pure (+)DMY is desired for treating chronic pharyngitis and alcohol use disorders, only DMY racemate is commercially available due to prolonged exposure time to high temperature and the presence of metal ions during industrial extraction, which cause racemization of the homochiral (+)DMY. We have developed an extraction method for successfully obtain optically pure (+)DMY. We have further assessed the physicochemical properties of the two phases using PXRD, DSC, TGA, FTIR, and moisture sorption. Among them, PXRD and FT-IR are suitable for quickly distinguishing homochiral (+)DMY from racemic (±)DMY. Lastly, with the aid of cocrystallization with theophylline, the absolute configuration of homochiral (+)DMY was identified to be (2R, 3R). PMID:27418561

  20. The synthesis and hydrogen storage properties of pure nanostructured Mg2FeH6.

    PubMed

    Zhang, Xuanzhou; Yang, Rong; Qu, Jianglan; Zhao, Wei; Xie, Lei; Tian, Wenhuai; Li, Xingguo

    2010-03-01

    In this work, pure nanostructured Mg(2)FeH(6) is successfully synthesized by sintering of a mixture of 2Mg + Fe nanoparticles. The successful preparation of pure Mg(2)FeH(6) can be attributed to the small particle sizes of Mg and Fe nanoparticles prepared by hydrogen plasma-metal reaction (HPMR), which benefits the synthesis. The hydrogen storage properties of Mg(2)FeH(6) and the synthesis mechanism of the Mg-Fe-H system are studied. The sample desorbs 5.0 wt% of hydrogen rapidly in 6 min under an initial hydrogen pressure of approximately 100 Pa at 623 K. The enthalpy and entropy of the reaction are deduced from the equilibrium plateau pressures of the desorption isotherms. The obtained Mg(2)FeH(6) shows favorable hydrogen storage properties due to the specific nanostructure of the materials.

  1. Studies on structural and electrical properties of pure and doped h-YMnO3

    NASA Astrophysics Data System (ADS)

    Rathod, K. N.; Rajyaguru, Bhargav; Solanki, Sapana; Shrimali, V. G.; Sagapariya, Khushal; Markna, J. H.; Solanki, P. S.; Shah, N. A.

    2016-05-01

    In the present communication, we report the results of the structural and electrical studies on pure YMnO3 (YMO) and Zr doped Y0.95Zr0.05MnO3 (YZMO) samples, synthesized using low cost sol-gel technique. To understand the structural properties, structural phases present and effect of doping on the structural behavior, X-ray diffraction (XRD) measurements were carried out for both the samples understudy. XRD results reveal the single phasic nature of both the samples having hexagonal unit cell structure. Improved crystal structure has been observed for pure YMnO3 sample while doping of Zr at Y-site degrades the structure of the sample. Improved dielectric constant and enhanced AC conductivity (σa) have been discussed on the basis of charge carrier polarization and correlated barrier hopping due to the localized state.

  2. Preparation of pure chitosan film using ternary solvents and its super absorbency.

    PubMed

    Wang, Xuejun; Lou, Tao; Zhao, Wenhua; Song, Guojun

    2016-11-20

    Chemical modification and graft copolymerization were commonly adopted to prepare super absorbent materials. However, physical microstructure of pure chitosan film was optimized to improve the water uptake capacity in this study. Chitosan films with micro-nanostructure were prepared by a ternary solvent system. The optimal process parameters are 1% acetic acid water solution: dioxane: dimethyl sulfoxide=90: 2.5: 7.5 (v/v/v) with chitosan concentration at 1.25% (w/v). The water uptake capacity of the chitosan film prepared under the optimal process parameters was 896g/g. The prepared chitosan films also exhibited high water uptake capacity in response to external stimuli such as temperature, pH and salt. This finding may provide another way for improving the water absorbency. The pure chitosan film may find potential applications especially in the fields of hygienic products and biomedicine due to its super water absorbency and nontoxicity. PMID:27561494

  3. Phase-pure iron pyrite nanocrystals for low-cost photodetectors

    PubMed Central

    2014-01-01

    Earth-abundant iron pyrite (FeS2) shows great potential as a light absorber for solar cells and photodetectors due to their high absorption coefficient (>105 cm-1). In this paper, high-quality phase-pure and single crystalline pyrite nanocrystals were synthesized via facile, low-cost, and environment friendly hydrothermal method. The molar ratio of sulphur to iron and the reaction time play a crucial role in determining the quality and morphology of FeS2 nanocrystals. X-ray diffraction and high-resolution transmission electron microscopy confirm that phase-pure and single crystalline pyrite nanocrystals can be synthesized with high sulphur to iron molar ratio and sufficient reaction time. For the first time, a crystalline nanogap pyrite photodetector with promising photocurrent and UV-visible photoresponse has been fabricated. This work further demonstrates a facile route to synthesize high-quality FeS2 nanomaterials and their potential in optoelectronic applications. PMID:25317102

  4. Operation of RF driven negative ion source in a pure-hydrogen mode

    SciTech Connect

    Abdrashitov, G.; Belchenko, Yu. Gusev, I.; Senkov, D.; Sanin, A.; Shikhovtsev, I.; Kondakov, A.; Ivanov, A. A.; Sotnikov, O.

    2015-04-08

    The production of negative hydrogen ions in the radio-frequency driven long-pulsed source with external antenna is studied. RF drivers with various geometry of external antenna, Faraday shield and magnets at the rear flange were examined. H- beam extraction through the single emission aperture was performed in the source pure-hydrogen mode with no external seed of alkali additives. H- beam with ion emission current density up to 5 mA/cm{sup 2} and energy up to 75 keV was regularly obtained in the 1 s pulses of the pure-hydrogen mode. The regular temporal increase of H- ion production due to deposition of impurities on the plasma grid surface was recorded. The H- emission current density increased up to 9 mA/cm{sup 2} in this case.

  5. Laser Surface Alloying of Copper, Manganese, and Magnesium with Pure Aluminum Substrate

    NASA Astrophysics Data System (ADS)

    Jiru, Woldetinsay G.; Sankar, M. Ravi; Dixit, Uday S.

    2016-03-01

    Laser surface alloying is one of the recent technologies used in the manufacturing sector for improving the surface properties of the metals. Light weight materials like aluminum alloys, titanium alloys, and magnesium alloys are used in the locomotive, aerospace, and structural applications. In the present work, an experimental study was conducted to improve the surface hardness of commercially pure aluminum plate. CO2 laser is used to melt pre-placed powders of pure copper, manganese, and magnesium. Microstructure of alloyed surface was analyzed using optical microscope. The best surface alloying was obtained at the optimum values of laser parameters, viz., laser power, scan speed, and laser beam diameter. In the alloyed region, microhardness increased from 30 HV0.5 to 430 HV0.5, while it was 60 HV0.5 in the heat-affected region. Tensile tests revealed some reduction in the strength and total elongation due to alloying. On the other hand, corrosion resistance improved.

  6. Extraction of distance restraints from pure shift NOE experiments

    NASA Astrophysics Data System (ADS)

    Kaltschnee, Lukas; Knoll, Kevin; Schmidts, Volker; Adams, Ralph W.; Nilsson, Mathias; Morris, Gareth A.; Thiele, Christina M.

    2016-10-01

    NMR techniques incorporating pure shift methods to improve signal resolution have recently attracted much attention, owing to their potential use in studies of increasingly complex molecular systems. Extraction of frequencies from these simplified spectra enables easier structure determination, but only a few of the methods presented provide structural parameters derived from signal integral measurements. In particular, for quantification of the nuclear Overhauser effect (NOE) it is highly desirable to utilize pure shift techniques where signal overlap normally prevents accurate signal integration, to enable measurement of a larger number of interatomic distances. However, robust methods for the measurement of interatomic distances using the recently developed pure shift techniques have not been reported to date. In this work we discuss some of the factors determining the accuracy of measurements of signal integrals in interferogram-based Zangger-Sterk (ZS) pure shift NMR experiments. The ZS broadband homodecoupling technique is used in different experiments designed for quantitative NOE determination from pure shift spectra. It is shown that the techniques studied can be used for quantitative extraction of NOE-derived distance restraints, as exemplified for the test case of strychnine.

  7. Freezing of Water Droplet due to Evaporation

    NASA Astrophysics Data System (ADS)

    Satoh, Isao; Fushinobu, Kazuyoshi; Hashimoto, Yu

    In this study, the feasibility of cooling/freezing of phase change.. materials(PCMs) due to evaporation for cold storage systems was experimentally examined. A pure water was used as the test PCM, since the latent heat due to evaporation of water is about 7 times larger than that due to freezing. A water droplet, the diameter of which was 1-4 mm, was suspended in a test cell by a fine metal wire (O. D.= 100μm),and the cell was suddenly evacuated up to the pressure lower than the triple-point pressure of water, so as to enhance the evaporation from the water surface. Temperature of the droplet was measured by a thermocouple, and the cooling/freezing behavior and the temperature profile of the droplet surface were captured by using a video camera and an IR thermo-camera, respectively. The obtained results showed that the water droplet in the evacuated cell is effectively cooled by the evaporation of water itself, and is frozen within a few seconds through remarkable supercooling state. When the initial temperature of the droplet is slightly higher than the room temperature, boiling phenomena occur in the droplet simultaneously with the freezing due to evaporation. Under such conditions, it was shown that the degree of supercooling of the droplet is reduced by the bubbles generated in the droplet.

  8. Excitation of coherent propagating spin waves by pure spin currents

    PubMed Central

    Demidov, Vladislav E.; Urazhdin, Sergei; Liu, Ronghua; Divinskiy, Boris; Telegin, Andrey; Demokritov, Sergej O.

    2016-01-01

    Utilization of pure spin currents not accompanied by the flow of electrical charge provides unprecedented opportunities for the emerging technologies based on the electron's spin degree of freedom, such as spintronics and magnonics. It was recently shown that pure spin currents can be used to excite coherent magnetization dynamics in magnetic nanostructures. However, because of the intrinsic nonlinear self-localization effects, magnetic auto-oscillations in the demonstrated devices were spatially confined, preventing their applications as sources of propagating spin waves in magnonic circuits using these waves as signal carriers. Here, we experimentally demonstrate efficient excitation and directional propagation of coherent spin waves generated by pure spin current. We show that this can be achieved by using the nonlocal spin injection mechanism, which enables flexible design of magnetic nanosystems and allows one to efficiently control their dynamic characteristics. PMID:26818232

  9. Fast word reading in pure alexia: "fast, yet serial".

    PubMed

    Bormann, Tobias; Wolfer, Sascha; Hachmann, Wibke; Neubauer, Claudia; Konieczny, Lars

    2015-01-01

    Pure alexia is a severe impairment of word reading in which individuals process letters serially with a pronounced length effect. Yet, there is considerable variation in the performance of alexic readers with generally very slow, but also occasionally fast responses, an observation addressed rarely in previous reports. It has been suggested that "fast" responses in pure alexia reflect residual parallel letter processing or that they may even be subserved by an independent reading system. Four experiments assessed fast and slow reading in a participant (DN) with pure alexia. Two behavioral experiments investigated frequency, neighborhood, and length effects in forced fast reading. Two further experiments measured eye movements when DN was forced to read quickly, or could respond faster because words were easier to process. Taken together, there was little support for the proposal that "qualitatively different" mechanisms or reading strategies underlie both types of responses in DN. Instead, fast responses are argued to be generated by the same serial-reading strategy.

  10. Noninformative prior in the quantum statistical model of pure states

    NASA Astrophysics Data System (ADS)

    Tanaka, Fuyuhiko

    2012-06-01

    In the present paper, we consider a suitable definition of a noninformative prior on the quantum statistical model of pure states. While the full pure-states model is invariant under unitary rotation and admits the Haar measure, restricted models, which we often see in quantum channel estimation and quantum process tomography, have less symmetry and no compelling rationale for any choice. We adopt a game-theoretic approach that is applicable to classical Bayesian statistics and yields a noninformative prior for a general class of probability distributions. We define the quantum detection game and show that there exist noninformative priors for a general class of a pure-states model. Theoretically, it gives one of the ways that we represent ignorance on the given quantum system with partial information. Practically, our method proposes a default distribution on the model in order to use the Bayesian technique in the quantum-state tomography with a small sample.

  11. Faithful Transfer Arbitrary Pure States with Mixed Resources

    NASA Astrophysics Data System (ADS)

    Luo, Ming-Xing; Li, Lin; Ma, Song-Ya; Chen, Xiu-Bo; Yang, Yi-Xian

    2013-09-01

    In this paper, we show that some special mixed quantum resource experience the same property of pure entanglement such as Bell state for quantum teleportation. It is shown that one mixed state and three bits of classical communication cost can be used to teleport one unknown qubit compared with two bits via pure resources. The schemes are easily implement with model physical techniques. Moreover, these resources are also optimal and typical for faithfully remotely prepare an arbitrary qubit, two-qubit and three-qubit states with mixed quantum resources. Our schemes are completed as same as those with pure quantum entanglement resources except only 1 bit additional classical communication cost required. The success probability is independent of the form of the mixed resources.

  12. Fisher-Symmetric Informationally Complete Measurements for Pure States.

    PubMed

    Li, Nan; Ferrie, Christopher; Gross, Jonathan A; Kalev, Amir; Caves, Carlton M

    2016-05-01

    We introduce a new kind of quantum measurement that is defined to be symmetric in the sense of uniform Fisher information across a set of parameters that uniquely represent pure quantum states in the neighborhood of a fiducial pure state. The measurement is locally informationally complete-i.e., it uniquely determines these parameters, as opposed to distinguishing two arbitrary quantum states-and it is maximal in the sense of a multiparameter quantum Cramér-Rao bound. For a d-dimensional quantum system, requiring only local informational completeness allows us to reduce the number of outcomes of the measurement from a minimum close to but below 4d-3, for the usual notion of global pure-state informational completeness, to 2d-1. PMID:27203310

  13. Actuating dielectric elastomers in pure shear deformation by elastomeric conductors

    SciTech Connect

    Wang, Yin; Chen, Baohong; Zhou, Jinxiong; Bai, Yuanyuan; Wang, Hong

    2014-02-10

    Pure shear experiments are commonly used to characterize dielectric elastomer (DE) material properties and to evaluate DE actuator/generator performance. It is increasingly important for many applications to replace conventional carbon grease electrodes with stretchable elastomeric conductors. We formulate a theory for DE with elastomeric conductors, synthesize transparent hydrogel as ionic conductors, and measure actuation of DE in pure shear deformation. Maximum 67% actuation strain is demonstrated. The theory agrees well with our measurement and also correlates well with reported experiments on DE with electronic conductors.

  14. Six open string disk amplitude in pure spinor superspace

    NASA Astrophysics Data System (ADS)

    Mafra, Carlos R.; Schlotterer, Oliver; Stieberger, Stephan; Tsimpis, Dimitrios

    2011-05-01

    The tree-level amplitude of six massless open strings is computed using the pure spinor formalism. The OPE poles among integrated and unintegrated vertices can be efficiently organized according to the cohomology of pure spinor superspace. The identification and use of these BRST structures and their interplay with the system of equations fulfilled by the generalized Euler integrals allow the full supersymmetric six-point amplitude to be written in compact form. Furthermore, the complete set of extended Bern-Carrasco-Johansson relations are derived from the monodromy properties of the disk world-sheet and explicitly verified for the supersymmetric numerator factors.

  15. PURE CULTIVATION IN VIVO OF VACCINE VIRUS FREE FROM BACTERIA

    PubMed Central

    Noguchi, Hideyo

    1915-01-01

    Vaccine virus freed from all associated bacteria by means of suitable disinfecting agents can be propagated in a pure state in the testicles of rabbits and bulls. The virus cultivated in this manner is not only devoid of all bacteria, but appears capable of indefinite transfer from one animal to another. Sixty passages in rabbits of a pure strain have been made within one year. Several transfers from testicle to testicle are required to bring about accurate adaptation of the virus to the testicular parenchyma, so that continued propagation in this way can be certainly secured. During the first transfers from testicle to testicle the activity of the virus may be less than the original skin specimen from which the pure strain was derived; but as the transfers proceed the activity rises until, when the adaptation is complete, the activity of the testicular equals that of the skin strain. The multiplication of the virus within the testicle is maximum on the fourth or fifth day after inoculation; the quantity of virus remains about stationary until the eighth day, when diminution begins. At the expiration of five weeks no more virus could be detected in the testicle. The vaccinal processes in the skin, cornea, and testicle of rabbits are practically identical whether the virus employed for the inoculation has been the original skin strain or the pure testicular strain; and the skin lesions produced in the calf with the two strains are also identical. In conformity with the finding mentioned in the last paragraph it has been found that human beings react to the pure testicular strain of vaccine virus in an entirely typical manner. In the case both of original vaccination and revaccination the vaccinal effects cannot be distinguished from those arising from uncomplicated skin virus. Pure strains of testicular virus are readily produced, and once secured they may be propagated in a pure state by the method described in rabbits or bulls without difficulty and with economy

  16. Pure tone audiometry: comparison of general practice and hospital services

    PubMed Central

    Smith, Michael C.F.; Cable, Hugh R.; Wilmot, John F.

    1988-01-01

    Pure tone audiometry was obtained for both ears of 32 children by a general practitioner using a simple audiometer in his surgery, and by audiometricians in a hospital department on the same day. Comparing the worst hearing threshold at any of the three tested frequencies, the general practitioner did not find any ears to hear more than 10 dB better than the hospital (no false negatives). However, there were six false positives (9%) where the general practitioner identified an apparent hearing loss of greater than 15 dB. It is concluded that pure tone audiometry could be carried out accurately in the practice. PMID:3267745

  17. Irritable bowel syndrome: a mild disorder; purely symptomatic treatment.

    PubMed

    2009-04-01

    (1) Patients frequently complain of occasional bowel movement disorders, associated with abdominal pain or discomfort, but they are rarely due to an underlying organ involvement. Even when patients have recurrent symptoms, serious disorders are no more frequent in these patients than in the general population, unless other manifestations, anaemia, or an inflammatory syndrome is also present; (2) There is currently no way of radically modifying the natural course of recurrent irritable bowel syndrome; (3) The effects of antispasmodics on abdominal pain have been tested in about 20 randomised controlled trials. Pinaverium and peppermint essential oil have the best-documented efficacy and only moderate adverse effects. Antispasmodics with marked atropinic effects do not have a favourable risk-benefit balance; (4) Tricylic antidepressants seem to have only modest analgesic effects in this setting. In contrast, their adverse effects are frequent and they have somewhat negative risk-benefit balances. Nor has the efficacy of selective serotonin reuptake inhibitor antidepressants (SSRIs) been demonstrated; (5) Alosetron and tegaserod carry a risk of potentially life-threatening adverse effects and therefore have negative risk-benefit balances; (6) Seeds of plants such as psyllium and ispaghul, as well as raw apples and pears, have a limited impact on constipation and pain. Osmotic laxatives are effective on constipation. Symptomatic treatments for constipation can sometimes aggravate abdominal discomfort; (7) Loperamide has been poorly assessed in patients with recurrent irritable bowel syndrome with diarrhoea. It modestly slows bowel movement but does not relieve pain or abdominal discomfort; (8) Dietary measures have not been tested in comparative trials. Some patients are convinced that certain foods provoke a recurrence of irritable bowel syndrome, but restrictive diets carry a risk of nutritional deficiencies; (9) Various techniques intended to control emotional and

  18. In vitro and in vivo comparison of binary Mg alloys and pure Mg.

    PubMed

    Myrissa, Anastasia; Agha, Nezha Ahmad; Lu, Yiyi; Martinelli, Elisabeth; Eichler, Johannes; Szakács, Gábor; Kleinhans, Claudia; Willumeit-Römer, Regine; Schäfer, Ute; Weinberg, Annelie-Martina

    2016-04-01

    Biodegradable materials are under investigation due to their promising properties for biomedical applications as implant material. In the present study, two binary magnesium (Mg) alloys (Mg2Ag and Mg10Gd) and pure Mg (99.99%) were used in order to compare the degradation performance of the materials in in vitro to in vivo conditions. In vitro analysis of cell distribution and viability was performed on discs of pure Mg, Mg2Ag and Mg10Gd. The results verified viable pre-osteoblast cells on all three alloys and no obvious toxic effect within the first two weeks. The degradation rates in in vitro and in vivo conditions (Sprague-Dawley® rats) showed that the degradation rates differ especially in the 1st week of the experiments. While in vitro Mg2Ag displayed the fastest degradation rate, in vivo, Mg10Gd revealed the highest degradation rate. After four weeks of in vitro immersion tests, the degradation rate of Mg2Ag was significantly reduced and approached the values of pure Mg and Mg10Gd. Interestingly, after 4 weeks the estimated in vitro degradation rates approximate in vivo values. Our systematic experiment indicates that a correlation between in vitro and in vivo observations still has some limitations that have to be considered in order to perform representative in vitro experiments that display the in vivo situation.

  19. Similarities and differences between learning abilities, "pure" learning disabilities, "pure" ADHD and comorbid ADHD with learning disabilities.

    PubMed

    Mangina, Constantine A; Beuzeron-Mangina, Helen

    2009-08-01

    This research pursues the crucial question of the differentiation of preadolescents with "Pure" ADHD, comorbid ADHD with learning disabilities, "Pure" learning disabilities and age-matched normal controls. For this purpose, Topographic Mapping of Event-Related Brain Potentials (ERPs) to a Memory Workload Paradigm with visually presented words, Bilateral Electrodermal Activity during cognitive workload and Mangina-Test performance were used. The analysis of Topographic distribution of amplitudes revealed that normal preadolescents were significantly different from "Pure" ADHD (P<0.0001), "Pure" learning disabilities (P<0.0001), and comorbid ADHD with learning disabilities (P<0.0009), by displaying enhanced prefrontal and frontal negativities (N450). In contrast, preadolescents with "Pure" ADHD and comorbid ADHD with learning disabilities have shown a marked reduction of prefrontal and frontal negativities (N450). As for the "Pure" Learning Disabled preadolescents, very small positivities (P450) in prefrontal and frontal regions were obtained as compared to the other pathological groups. Bilateral Electrodermal Activity during cognitive workload revealed a significant main effect for groups (P<0.00001), Left versus Right (P=0.0029) and sessions (P=0.0136). A significant main effect for the Mangina-Test performance which separated the four groups was found (P<0.000001). Overall, these data support the existence of clear differences and similarities between the pathological preadolescent groups as opposed to age-matched normal controls. The psychophysiological differentiation of these groups, provides distinct biological markers which integrate central, autonomic and neuropsychometric variables by targeting the key features of these pathologies for diagnosis and intervention strategies and by providing knowledge for the understanding of normal neurocognitive processes and functions.

  20. In vitro corrosion of pure magnesium and AZ91 alloy—the influence of thin electrolyte layer thickness

    PubMed Central

    Zeng, Rong-Chang; Qi, Wei-Chen; Zhang, Fen; Li, Shuo-Qi

    2016-01-01

    In vivo degradation predication faces a huge challenge via in vitro corrosion test due to the difficulty for mimicking the complicated microenvironment with various influencing factors. A thin electrolyte layer (TEL) cell for in vitro corrosion of pure magnesium and AZ91 alloy was presented to stimulate the in vivo corrosion in the micro-environment built by the interface of the implant and its neighboring tissue. The results demonstrated that the in vivo corrosion of pure Mg and the AZ91 alloy was suppressed under TEL condition. The AZ91 alloy was more sensitive than pure Mg to the inhibition of corrosion under a TEL thickness of less than 200 µm. The TEL thickness limited the distribution of current, and thus localized corrosion was more preferred to occur under TEL condition than in bulk solution. The TEL cell might be an appropriate approach to simulating the in vivo degradation of magnesium and its alloys. PMID:26816655

  1. Spontaneous volume magnetostriction and non-Stoner behavior of the valence band in pure hcp Gd

    NASA Astrophysics Data System (ADS)

    Khmelevskyi, S.; Turek, I.; Mohn, P.

    2004-10-01

    Employing the disordered local moment formalism in combination with first-principles band-structure calculations, we study the behavior of the valence band in pure hcp Gd upon disorder of the local 4f GD moments. We show that the large value of the spontaneous volume magnetostriction in Gd is entirely due to changes in the magnetic state of the valence band at Tc and can be calculated in good agreement with experiment. The local exchange splitting of the valence band persists above Tc , which is in strong disagreement with the conventional Stoner picture. The analysis of our results provides a theoretical background for the discussion of recent photoemission experiments.

  2. Generation and coherent control of pure spin currents via terahertz pulses

    SciTech Connect

    Schüler, Michael Berakdar, Jamal

    2014-04-21

    We inspect the time and spin-dependent, inelastic tunneling in engineered semiconductor-based double quantum well driven by time-structured terahertz pulses. An essential ingredient is an embedded spin-active structure with vibrational modes that scatter the pulse driven carriers. Due to the different time scales of the charge and spin dynamics, the spin-dependent electron-vibron coupling may result in pure net spin current (with negligible charge current). Heating the vibrational site may affect the resulting spin current. Furthermore, by controlling the charge dynamics, the spin dynamics and the generated spin current can be manipulated and switched on and off coherently.

  3. Creating second-order nonlinearity in pure synthetic silica optical fibers by thermal poling.

    PubMed

    An, Honglin; Fleming, Simon

    2007-04-01

    A twin-hole optical fiber with pure synthetic silicate glass between the two electrode holes was thermally poled. The induced second-order nonlinearity (SON) was located at the core-cladding interface sections that were nearly parallel to the poling electric field. The polarization dependence of the induced SON suggests that nonlinearity was due to the presence of a space-charge field, which was probably formed by electron migration among the defects located at the core-cladding interface. The magnitude of the induced SON was measured to be approximately 0.06 pm /V.

  4. Idealization in Chemistry: Pure Substance and Laboratory Product

    ERIC Educational Resources Information Center

    Fernández-González, Manuel

    2013-01-01

    This article analyzes the concept of idealization in chemistry and the role played by pure substance and laboratory product. This topic has evident repercussions in the educational contexts that are applied to the science classroom, which are highlighted throughout the text. A common structure for knowledge construction is proposed for both…

  5. A Hybrid Sensing Approach for Pure and Adulterated Honey Classification

    PubMed Central

    Subari, Norazian; Saleh, Junita Mohamad; Shakaff, Ali Yeon Md; Zakaria, Ammar

    2012-01-01

    This paper presents a comparison between data from single modality and fusion methods to classify Tualang honey as pure or adulterated using Linear Discriminant Analysis (LDA) and Principal Component Analysis (PCA) statistical classification approaches. Ten different brands of certified pure Tualang honey were obtained throughout peninsular Malaysia and Sumatera, Indonesia. Various concentrations of two types of sugar solution (beet and cane sugar) were used in this investigation to create honey samples of 20%, 40%, 60% and 80% adulteration concentrations. Honey data extracted from an electronic nose (e-nose) and Fourier Transform Infrared Spectroscopy (FTIR) were gathered, analyzed and compared based on fusion methods. Visual observation of classification plots revealed that the PCA approach able to distinct pure and adulterated honey samples better than the LDA technique. Overall, the validated classification results based on FTIR data (88.0%) gave higher classification accuracy than e-nose data (76.5%) using the LDA technique. Honey classification based on normalized low-level and intermediate-level FTIR and e-nose fusion data scored classification accuracies of 92.2% and 88.7%, respectively using the Stepwise LDA method. The results suggested that pure and adulterated honey samples were better classified using FTIR and e-nose fusion data than single modality data. PMID:23202033

  6. About the Role of Visual Field Defects in Pure Alexia

    ERIC Educational Resources Information Center

    Pflugshaupt, Tobias; Gutbrod, Klemens; Wurtz, Pascal; von Wartburg, Roman; Nyffeler, Thomas; de Haan, Bianca; Karnath, Hans-Otto; Mueri, Rene M.

    2009-01-01

    Pure alexia is an acquired reading disorder characterized by a disproportionate prolongation of reading time as a function of word length. Although the vast majority of cases reported in the literature show a right-sided visual defect, little is known about the contribution of this low-level visual impairment to their reading difficulties. The…

  7. Computer Pure-Tone and Operator Stress: Report III.

    ERIC Educational Resources Information Center

    Dow, Caroline; Covert, Douglas C.

    Pure-tone sound at 15,750 Herz generated by flyback transformers in many computer and video display terminal (VDT) monitors has stress-related productivity effects in some operators, especially women. College-age women in a controlled experiment simulating half a normal work day showed responses within the first half hour of exposure to a tone…

  8. Effect of dissociation on thermodynamic properties of pure diatomic gases

    NASA Technical Reports Server (NTRS)

    Woolley, Harold W

    1955-01-01

    A graphical method is described by which the enthalpy, entropy, and compressibility factor for the equilibrium mixture of atoms and diatomic molecules for pure gaseous elements may be obtained and shown for any dissociating element for which the necessary data exist. Results are given for hydrogen, oxygen, and nitrogen. The effect of dissociation on the heat capacity is discussed briefly.

  9. Chemical modification of pure titanium surfaces for oral implants.

    PubMed

    Pimenta, J; Castro, F

    1999-01-01

    A technique that achieves different pure titanium surfaces depending on acid concentration and exposure time is described. It is possible to obtain, with the same chemical treatment, both large pits and small rugosities. This technique may have interesting applications in oral implants.

  10. Complex windmill transformation producing new purely magnetic fluids

    NASA Astrophysics Data System (ADS)

    Lozanovski, C.; Wylleman, L.

    2011-04-01

    Minimal complex windmill transformations of G2IB(ii) spacetimes (admitting a two-dimensional Abelian group of motions of the so-called Wainwright B(ii) class) are defined and the compatibility with a purely magnetic Weyl tensor is investigated. It is shown that the transformed spacetimes cannot be perfect fluids or purely magnetic Einstein spaces. We then determine which purely magnetic perfect fluids (PMpfs) can be windmill-transformed into purely magnetic anisotropic fluids (PMafs). Assuming separation of variables, complete integration produces two, algebraically general, G2I-B(ii) PMpfs: a solution with zero 4-acceleration vector and spatial energy-density gradient, previously found by the authors, and a new solution in terms of Kummer's functions, where these vectors are aligned and non-zero. The associated windmill PMafs are rotating but non-expanding. Finally, an attempt to relate the spacetimes to each other by a simple procedure leads to a G2I-B(ii) one-parameter PMaf generalization of the previously found metric.

  11. Pure Mediated Priming: A Retrospective Semantic Matching Model

    ERIC Educational Resources Information Center

    Jones, Lara L.

    2010-01-01

    Mediated priming refers to the activation of a target (e.g., "stripes") by a prime (e.g., "lion") that is related indirectly via a connecting mediator (e.g., tiger). In previous mediated priming studies (e.g., McNamara & Altarriba, 1988), the mediator was associatively related to the prime. In contrast, pure mediated priming (e.g., "spoon" [right…

  12. A pure-sampling quantum Monte Carlo algorithm

    SciTech Connect

    Ospadov, Egor; Rothstein, Stuart M.

    2015-01-14

    The objective of pure-sampling quantum Monte Carlo is to calculate physical properties that are independent of the importance sampling function being employed in the calculation, save for the mismatch of its nodal hypersurface with that of the exact wave function. To achieve this objective, we report a pure-sampling algorithm that combines features of forward walking methods of pure-sampling and reptation quantum Monte Carlo (RQMC). The new algorithm accurately samples properties from the mixed and pure distributions simultaneously in runs performed at a single set of time-steps, over which extrapolation to zero time-step is performed. In a detailed comparison, we found RQMC to be less efficient. It requires different sets of time-steps to accurately determine the energy and other properties, such as the dipole moment. We implement our algorithm by systematically increasing an algorithmic parameter until the properties converge to statistically equivalent values. As a proof in principle, we calculated the fixed-node energy, static α polarizability, and other one-electron expectation values for the ground-states of LiH and water molecules. These quantities are free from importance sampling bias, population control bias, time-step bias, extrapolation-model bias, and the finite-field approximation. We found excellent agreement with the accepted values for the energy and a variety of other properties for those systems.

  13. Pure Spinor Formalism for Osp N\\vert 4) Backgrounds

    NASA Astrophysics Data System (ADS)

    Fré, Pietro; Grassi, Pietro Antonio

    2012-12-01

    We start from the Maurer-Cartan (MC) equations of the Osp(N\\vert 4) superalgebras satisfied by the left-invariant superforms realized on supercoset manifolds of the corresponding supergroups and we derive some new pure spinor constraints. They are obtained by "ghostifying" the MC forms and extending the differential d to a BRST differential. From the superalgebras \\hat G = Osp(N\\vert 4) we single out different subalgebras H \\subset \\hat G associated with the different cosets \\hat {G}/H: each choice of ℍ leads to a different weakening of the pure spinor constraints. In each case, the number of parameter is counted and we show that in the cases of Osp(6|4)/U(3)×SO(1, 3), Osp(4|4)/SO(3) ×SO(1, 3) and finally Osp(4|4)/U(2) ×SO(1, 3) the bosonic and fermionic degrees of freedom match in order to provide a c = 0 superconformal field theory. We construct both the Green-Schwarz and the pure spinor sigma model for the case Osp(6|4)/U(3)×SO(1, 3) corresponding to AdS4 ×ℙ3. The pure spinor sigma model can be consistently quantized.

  14. Number Reading in Pure Alexia--A Review

    ERIC Educational Resources Information Center

    Starrfelt, Randi; Behrmann, Marlene

    2011-01-01

    It is commonly assumed that number reading can be intact in patients with pure alexia, and that this dissociation between letter/word recognition and number reading strongly constrains theories of visual word processing. A truly selective deficit in letter/word processing would strongly support the hypothesis that there is a specialized system or…

  15. Three Variations on a Theme: The Power of Pure Empathy.

    ERIC Educational Resources Information Center

    Kottler, Jeffrey A.; Montgomery, Marilyn J.; Marbley, Aretha Faye

    1998-01-01

    With the counseling profession's increased emphasis on developing brief therapies, applying innovative techniques, and measuring outcomes, helping someone feel understood is sometimes neglected. Three narratives by humanistic practitioners illustrate the value of pure empathy in our work with clients, students, and others in our diverse…

  16. 77 FR 59979 - Pure Magnesium (Granular) From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... this five-year review. Background The Commission instituted this review on February 1, 2012 (77 FR 5049) and determined on May 7, 2012 that it would conduct an expedited review (77 FR 32668, June 1, 2012... COMMISSION Pure Magnesium (Granular) From China Determination On the basis of the record \\1\\ developed in...

  17. Molarity (Aromic Density) of the Elements as Pure Crystals.

    ERIC Educational Resources Information Center

    Pauling, Linus; Herman, Zelek S.

    1985-01-01

    Provides background information for teachers on the atomic density of the elements as pure crystals. Atomic density is defined as the reciprocal of the atomic volume. Includes atomic-density diagrams which were prepared using the atomic-volume values given by Singman, supplemented by additional values for some allotropes. (JN)

  18. A Graphical Representation for the Fugacity of a Pure Substance

    ERIC Educational Resources Information Center

    Book, Neil L.; Sitton, Oliver C.

    2010-01-01

    The thermodynamic equations used to define and compute the fugacity of a pure substance are depicted as processes on a semi-logarithmic plot of pressure vs. molar Gibbs energy (PG diagram) with isotherms for the substance behaving as an ideal gas superimposed. The PG diagram clearly demonstrates the physical basis for the definitions and the…

  19. Information balance in quantum teleportation with an arbitrary pure state

    SciTech Connect

    Li Li; Chen Zengbing

    2005-07-15

    We study a general teleportation scheme with an arbitrary two-party pure state and derive a tight bound of the teleportation fidelity with a predesigned estimation of the unknown state to be teleported. This bound shows a piecewise balance between information gain and state disturbance. We also explain possible physical significance of the balance.

  20. A pure-sampling quantum Monte Carlo algorithm

    NASA Astrophysics Data System (ADS)

    Ospadov, Egor; Rothstein, Stuart M.

    2015-01-01

    The objective of pure-sampling quantum Monte Carlo is to calculate physical properties that are independent of the importance sampling function being employed in the calculation, save for the mismatch of its nodal hypersurface with that of the exact wave function. To achieve this objective, we report a pure-sampling algorithm that combines features of forward walking methods of pure-sampling and reptation quantum Monte Carlo (RQMC). The new algorithm accurately samples properties from the mixed and pure distributions simultaneously in runs performed at a single set of time-steps, over which extrapolation to zero time-step is performed. In a detailed comparison, we found RQMC to be less efficient. It requires different sets of time-steps to accurately determine the energy and other properties, such as the dipole moment. We implement our algorithm by systematically increasing an algorithmic parameter until the properties converge to statistically equivalent values. As a proof in principle, we calculated the fixed-node energy, static α polarizability, and other one-electron expectation values for the ground-states of LiH and water molecules. These quantities are free from importance sampling bias, population control bias, time-step bias, extrapolation-model bias, and the finite-field approximation. We found excellent agreement with the accepted values for the energy and a variety of other properties for those systems.

  1. Enzymatic Synthesis of Single-Stranded Clonal Pure Oligonucleotides.

    PubMed

    Ducani, Cosimo; Högberg, Björn

    2017-01-01

    Single-stranded oligonucleotides, or oligodeoxyribonucleotides (ODNs), are very important in several fields of science such as molecular biology, diagnostics, nanotechnology, and gene therapy. They are usually chemically synthesized. Here we describe an enzymatic method which enables us to synthesize pure oligonucleotides which can be up to several hundred long bases. PMID:27671934

  2. Entropy for quantum pure states and quantum H theorem

    NASA Astrophysics Data System (ADS)

    Han, Xizhi; Wu, Biao

    2015-06-01

    We construct a complete set of Wannier functions that are localized at both given positions and momenta. This allows us to introduce the quantum phase space, onto which a quantum pure state can be mapped unitarily. Using its probability distribution in quantum phase space, we define an entropy for a quantum pure state. We prove an inequality regarding the long-time behavior of our entropy's fluctuation. For a typical initial state, this inequality indicates that our entropy can relax dynamically to a maximized value and stay there most of time with small fluctuations. This result echoes the quantum H theorem proved by von Neumann [Zeitschrift für Physik 57, 30 (1929), 10.1007/BF01339852]. Our entropy is different from the standard von Neumann entropy, which is always zero for quantum pure states. According to our definition, a system always has bigger entropy than its subsystem even when the system is described by a pure state. As the construction of the Wannier basis can be implemented numerically, the dynamical evolution of our entropy is illustrated with an example.

  3. A hybrid sensing approach for pure and adulterated honey classification.

    PubMed

    Subari, Norazian; Mohamad Saleh, Junita; Md Shakaff, Ali Yeon; Zakaria, Ammar

    2012-01-01

    This paper presents a comparison between data from single modality and fusion methods to classify Tualang honey as pure or adulterated using Linear Discriminant Analysis (LDA) and Principal Component Analysis (PCA) statistical classification approaches. Ten different brands of certified pure Tualang honey were obtained throughout peninsular Malaysia and Sumatera, Indonesia. Various concentrations of two types of sugar solution (beet and cane sugar) were used in this investigation to create honey samples of 20%, 40%, 60% and 80% adulteration concentrations. Honey data extracted from an electronic nose (e-nose) and Fourier Transform Infrared Spectroscopy (FTIR) were gathered, analyzed and compared based on fusion methods. Visual observation of classification plots revealed that the PCA approach able to distinct pure and adulterated honey samples better than the LDA technique. Overall, the validated classification results based on FTIR data (88.0%) gave higher classification accuracy than e-nose data (76.5%) using the LDA technique. Honey classification based on normalized low-level and intermediate-level FTIR and e-nose fusion data scored classification accuracies of 92.2% and 88.7%, respectively using the Stepwise LDA method. The results suggested that pure and adulterated honey samples were better classified using FTIR and e-nose fusion data than single modality data. PMID:23202033

  4. Distortion-Product Emissions and Pure-Tone Behavioral Thresholds.

    NASA Astrophysics Data System (ADS)

    Harris, Frances Pauline

    Distortion-product emissions (DPEs) are tonal responses that may be detected in the ear canal when the ear is stimulated simultaneously by two tones that are closely spaced in frequency. In experimental animals, DPEs are reduced in amplitude or are eliminated when cochlear function is disrupted. This association has not been investigated in human subjects. This study was designed to investigate the relation of cochlear status, as determined by pure -tone behavioral thresholds, to DPE amplitude in human subjects. Forty men were selected as subjects. Twenty had normal hearing and 20 had high-frequency sensorineural hearing loss. Pure-tone behavioral thresholds were determined using conventional audiometric procedures for eight frequencies from 750 to 8000 Hz. DPEs were generated in the test ear of each subject by stimulating the ear with two tones, f1 and f2. The stimuli were selected to approximate audiometric test frequencies. Responses were detected by a sensitive microphone that was placed in the ear canal and were extracted by spectral analysis. Results of the study indicated that DPE amplitude was associated with pure-tone threshold. When audiometric threshold was <=10 dB HL, DPEs could be elicited at all test frequencies for 98% of subjects in both groups. Mean maximum emission amplitude ranged from 3 to 13 dB SPL across frequency. When pure-tone threshold was above 50 dB HL, DPEs were absent or were significantly attenuated. DPEs varied in amplitude when audiometric threshold was between these two extremes. The association of DPE amplitude were pure-tone threshold was frequency specific. DPE amplitude was maximal when pure-tone thresholds were <=10 dB HL and decreased as pure-tone behavioral threshold increased in the same subject. Repetition of the DPE protocol with five subjects from each group during separate test sessions indicated that the results were reliable over time. Results of the study have clinical implications. The technique may have potential

  5. Microstructure, corrosion properties and bio-compatibility of calcium zinc phosphate coating on pure iron for biomedical application.

    PubMed

    Chen, Haiyan; Zhang, Erlin; Yang, Ke

    2014-01-01

    In order to improve the biocompatibility and the corrosion resistance in the initial stage of implantation, a phosphate (CaZn2(PO4)2·2H2O) coating was obtained on the surface of pure iron by a chemical reaction method. The anti-corrosion property, the blood compatibility and the cell toxicity of the coated pure iron specimens were investigated. The coating was composed of some fine phosphate crystals and the surface of coating was flat and dense enough. The electrochemical data indicated that the corrosion resistance of the coated pure iron was improved with the increase of phosphating time. When the specimen was phosphated for 30min, the corrosion resistance (Rp) increased to 8006 Ω. Compared with that of the naked pure iron, the anti-hemolysis property and cell compatibility of the coated specimen was improved significantly, while the anti-coagulant property became slightly worse due to the existence of element calcium. It was thought that phosphating treatment might be an effective method to improve the biocompatibility of pure iron for biomedical application.

  6. Investigation into the Advantages of Pure Perovskite Film without PbI2 for High Performance Solar Cell

    PubMed Central

    Kwon, Uisik; Hasan, Md Mehedi; Yin, Wenping; Kim, Dasom; Ha, Na Young; Lee, Soonil; Ahn, Tae Kyu; Park, Hui Joon

    2016-01-01

    In CH3NH3PbI3-based high efficiency perovskite solar cells (PSCs), tiny amount of PbI2 impurity was often found with the perovskite crystal. However, for two-step solution process-based perovskite films, most of findings have been based on the films having different morphologies between with and without PbI2. This was mainly due to the inferior morphology of pure perovskite film without PbI2, inevitably produced when the remaining PbI2 forced to be converted to perovskite, so advantages of pure perovskite photoactive layer without PbI2 impurity have been overlooked. In this work, we designed a printing-based two-step process, which could not only generate pure perovskite crystal without PbI2, but also provide uniform and full surface coverage perovskite film, of which nanoscale morphology was comparable to that prepared by conventional two-step solution process having residual PbI2. Our results showed that, in two-step solution process-based PSC, pure perovskite had better photon absorption and longer carrier lifetime, leading to superior photocurrent generation with higher power conversion efficiency. Furthermore, this process was further applicable to prepare mixed phase pure perovskite crystal without PbI2 impurity, and we showed that the additional merits such as extended absorption to longer wavelength, increased carrier lifetime and reduced carrier recombination could be secured. PMID:27786257

  7. Pure and Pseudo-pure Fluid Thermophysical Property Evaluation and the Open-Source Thermophysical Property Library CoolProp

    PubMed Central

    2014-01-01

    Over the last few decades, researchers have developed a number of empirical and theoretical models for the correlation and prediction of the thermophysical properties of pure fluids and mixtures treated as pseudo-pure fluids. In this paper, a survey of all the state-of-the-art formulations of thermophysical properties is presented. The most-accurate thermodynamic properties are obtained from multiparameter Helmholtz-energy-explicit-type formulations. For the transport properties, a wider range of methods has been employed, including the extended corresponding states method. All of the thermophysical property correlations described here have been implemented into CoolProp, an open-source thermophysical property library. This library is written in C++, with wrappers available for the majority of programming languages and platforms of technical interest. As of publication, 110 pure and pseudo-pure fluids are included in the library, as well as properties of 40 incompressible fluids and humid air. The source code for the CoolProp library is included as an electronic annex. PMID:24623957

  8. Pure odd-order oscillators with constant excitation

    NASA Astrophysics Data System (ADS)

    Cveticanin, L.

    2011-02-01

    In this paper the excited vibrations of a truly nonlinear oscillator are analyzed. The excitation is assumed to be constant and the nonlinearity is pure (without a linear term). The mathematical model is a second-order nonhomogeneous differential equation with strong nonlinear term. Using the first integral, the exact value of period of vibration i.e., angular frequency of oscillator described with a pure nonlinear differential equation with constant excitation is analytically obtained. The closed form solution has the form of gamma function. The period of vibration depends on the value of excitation and of the order and coefficient of the nonlinear term. For the case of pure odd-order-oscillators the approximate solution of differential equation is obtained in the form of trigonometric function. The solution is based on the exact value of period of vibration. For the case when additional small perturbation of the pure oscillator acts, the so called 'Cveticanin's averaging method' for a truly nonlinear oscillator is applied. Two special cases are considered: one, when the additional term is a function of distance, and the second, when damping acts. To prove the correctness of the method the obtained results are compared with those for the linear oscillator. Example of pure cubic oscillator with constant excitation and linear damping is widely discussed. Comparing the analytically obtained results with exact numerical ones it is concluded that they are in a good agreement. The investigations reported in the paper are of special interest for those who are dealing with the problem of vibration reduction in the oscillator with constant excitation and pure nonlinear restoring force the examples of which can be found in various scientific and engineering systems. For example, such mechanical systems are seats in vehicles, supports for machines, cutting machines with periodical motion of the cutting tools, presses, etc. The examples can be find in electronics

  9. Emergence of equilibrium thermodynamic properties in quantum pure states. I. Theory

    SciTech Connect

    Fresch, Barbara; Moro, Giorgio J.

    2010-07-21

    Investigation on foundational aspects of quantum statistical mechanics recently entered a renaissance period due to novel intuitions from quantum information theory and to increasing attention on the dynamical aspects of single quantum systems. In the present contribution a simple but effective theoretical framework is introduced to clarify the connections between a purely mechanical description and the thermodynamic characterization of the equilibrium state of an isolated quantum system. A salient feature of our approach is the very transparent distinction between the statistical aspects and the dynamical aspects in the description of isolated quantum systems. Like in the classical statistical mechanics, the equilibrium distribution of any property is identified on the basis of the time evolution of the considered system. As a consequence equilibrium properties of quantum system appear to depend on the details of the initial state due to the abundance of constants of the motion in the Schroedinger dynamics. On the other hand the study of the probability distributions of some functions, such as the entropy or the equilibrium state of a subsystem, in statistical ensembles of pure states reveals the crucial role of typicality as the bridge between macroscopic thermodynamics and microscopic quantum dynamics. We shall consider two particular ensembles: the random pure state ensemble and the fixed expectation energy ensemble. The relation between the introduced ensembles, the properties of a given isolated system, and the standard quantum statistical description are discussed throughout the presentation. Finally we point out the conditions which should be satisfied by an ensemble in order to get meaningful thermodynamical characterization of an isolated quantum system.

  10. Emergence of equilibrium thermodynamic properties in quantum pure states. I. Theory.

    PubMed

    Fresch, Barbara; Moro, Giorgio J

    2010-07-21

    Investigation on foundational aspects of quantum statistical mechanics recently entered a renaissance period due to novel intuitions from quantum information theory and to increasing attention on the dynamical aspects of single quantum systems. In the present contribution a simple but effective theoretical framework is introduced to clarify the connections between a purely mechanical description and the thermodynamic characterization of the equilibrium state of an isolated quantum system. A salient feature of our approach is the very transparent distinction between the statistical aspects and the dynamical aspects in the description of isolated quantum systems. Like in the classical statistical mechanics, the equilibrium distribution of any property is identified on the basis of the time evolution of the considered system. As a consequence equilibrium properties of quantum system appear to depend on the details of the initial state due to the abundance of constants of the motion in the Schrodinger dynamics. On the other hand the study of the probability distributions of some functions, such as the entropy or the equilibrium state of a subsystem, in statistical ensembles of pure states reveals the crucial role of typicality as the bridge between macroscopic thermodynamics and microscopic quantum dynamics. We shall consider two particular ensembles: the random pure state ensemble and the fixed expectation energy ensemble. The relation between the introduced ensembles, the properties of a given isolated system, and the standard quantum statistical description are discussed throughout the presentation. Finally we point out the conditions which should be satisfied by an ensemble in order to get meaningful thermodynamical characterization of an isolated quantum system.

  11. Humification Processes of Different Pure Organic Sunstances in the Soil

    NASA Astrophysics Data System (ADS)

    Alianiello, F.; Mascia, M. G.; Valentini, M.; Cozzolino, S.

    2009-04-01

    The chemical composition and the structure of humic substances are not yet well known, due to the heterogeneity of their components. Different models have been proposed on their composition, but many doubts still exist on their chemical characteristics and their general structure. Different theories have been suggested also on the origins of humic substances and on the humification processes, and no one of them has been still universally accepted. Experimental results hardly can be generalised, since differences of soils, of the organic materials added to soil and of climate conditions provide heterogeneous results. Aim of this study was to follow the changes occurring to the chemical composition of organic substances added to soil and incubated under controlled conditions in a laboratory experiment, tracking the effects occurring to singular pure compounds, representative of the most abundant classes of compounds present in the organic matter. 4 pure compounds were added to two different soils and incubated for an year under controlled conditions of temperature and moisture (27°C, 2.5 pF). They were: lignin, cellulose, casein and tripalmitin. Lignin was chosen because it has been considered for long time the precursor of humic substances, while the others represent the most abundant classes of natural organic substances, i.e. proteins, carbohydrates and lipids. The material was added in the quantity necessary to double the organic C already present in the soil. Sub-samples were collected immediately after mixing, after 3 weeks, 3 months, 6 months and 1 year. The organic matter of the samples has been characterised by determination of total organic carbon, total extractable carbon, humic plus fulvic acids and calculation of humification parameters. Soil microbial biomass was determined immediately after sampling. Total organic carbon decreased in all the treated soils, as expected, but differences were detected among the different mixtures. Casein seemed to be

  12. [Clinical picture of pure corneal ulcers of different localizations].

    PubMed

    Tarasova, L N; Kudriashova, Iu I

    1999-01-01

    Pure corneal ulcers can be localized at the periphery and in the center. Peripheral ulcers are bilateral in 66% and multifocal in 48% cases. They are combined with local vasculitis of perilimbic vessels of the conjunctiva. In 84% cases the disease occurred in patients with connective tissue and articular diseases. Clinical picture of the peripheral corneal ulcer differs from Mourene's phagodenic ulcer. Central corneal ulcers are bilateral in 40% patients, are associated with primary and secondary "dry eye" syndrome in Sjogren's disease, rheumatoid arthritis, systemic vasculitis, Behçet's disease, and in 18% patients with cicatricial deformation of the conjunctiva after Stevens-Johnson's syndrome, trachoma, and chemical burns of the eyes. Pure corneal ulcers run a chronic relapsing course, complicated in one-fourth of patients by corneal perforation and secondary infections.

  13. Biomedical effects of mushrooms with emphasis on pure compounds.

    PubMed

    Paterson, R Russell M; Lima, Nelson

    2014-01-01

    Medicinal mushrooms show great promise for disease treatments. They have been employed in the Orient and Occident for thousands of years, although the practice has persisted in the East. They remain highly valuable. Authentic human trials and pure compounds are emphasized in this review of the most current literature. Polysaccharides from the fungi appear effective in cancer treatments and low-molecular-weight compounds also attract much interest. However, reports of toxicity must be taken seriously. Prescriptions for mushrooms and preparations need to be given by qualified medical practitioners. The reason why these preparations are not more widely used in the West is related to problems of (A) intellectual property rights, (B) mass production, and (C) obtaining pure compounds that retain activity. Mushroom compounds require testing against infectious diseases such as those caused by bacteria, because the current antibiotics are failing from resistances. Overall, the future is assured for medicinal mushrooms.

  14. New Formulation of Statistical Mechanics Using Thermal Pure Quantum States

    NASA Astrophysics Data System (ADS)

    Sugiura, Sho; Shimizu, Akira

    2014-03-01

    We formulate statistical mechanics based on a pure quantum state, which we call a "thermal pure quantum (TPQ) state". A single TPQ state gives not only equilibrium values of mechanical variables, such as magnetization and correlation functions, but also those of genuine thermodynamic variables and thermodynamic functions, such as entropy and free energy. Among many possible TPQ states, we discuss the canonical TPQ state, the TPQ state whose temperature is specified. In the TPQ formulation of statistical mechanics, thermal fluctuations are completely included in quantum-mechanical fluctuations. As a consequence, TPQ states have much larger quantum entanglement than the equilibrium density operators of the ensemble formulation. We also show that the TPQ formulation is very useful in practical computations, by applying the formulation to a frustrated two-dimensional quantum spin system.

  15. Synthesis and photoluminescence of ultra-pure germanium nanoparticles

    NASA Astrophysics Data System (ADS)

    Chivas, R.; Yerci, S.; Li, R.; Dal Negro, L.; Morse, T. F.

    2011-09-01

    We have used aerosol deposition to synthesize defect and micro-strain free, ultra-pure germanium nanoparticles. Transmission electron microscopy images show a core-shell configuration with highly crystalline core material. Powder X-ray diffraction measurements verify the presence of highly pure, nano-scale germanium with average crystallite size of 30 nm and micro-strain of 0.058%. X-ray photoelectron spectroscopy demonstrates that GeO x ( x ⩽ 2) shells cover the surfaces of the nanoparticles. Under optical excitation, these nanoparticles exhibit two separate emission bands at room temperature: a visible emission at 500 nm with 0.5-1 ns decay times and an intense near-infrared emission at 1575 nm with up to ˜20 μs lifetime.

  16. Control aspects of quantum computing using pure and mixed states.

    PubMed

    Schulte-Herbrüggen, Thomas; Marx, Raimund; Fahmy, Amr; Kauffman, Louis; Lomonaco, Samuel; Khaneja, Navin; Glaser, Steffen J

    2012-10-13

    Steering quantum dynamics such that the target states solve classically hard problems is paramount to quantum simulation and computation. And beyond, quantum control is also essential to pave the way to quantum technologies. Here, important control techniques are reviewed and presented in a unified frame covering quantum computational gate synthesis and spectroscopic state transfer alike. We emphasize that it does not matter whether the quantum states of interest are pure or not. While pure states underly the design of quantum circuits, ensemble mixtures of quantum states can be exploited in a more recent class of algorithms: it is illustrated by characterizing the Jones polynomial in order to distinguish between different (classes of) knots. Further applications include Josephson elements, cavity grids, ion traps and nitrogen vacancy centres in scenarios of closed as well as open quantum systems.

  17. Modeling pure culture heterotrophic production of polyhydroxybutyrate (PHB).

    PubMed

    Mozumder, Md Salatul Islam; Goormachtigh, Laurens; Garcia-Gonzalez, Linsey; De Wever, Heleen; Volcke, Eveline I P

    2014-03-01

    In this contribution a mechanistic model describing the production of polyhydroxybutyrate (PHB) through pure-culture fermentation was developed, calibrated and validated for two different substrates, namely glucose and waste glycerol. In both cases, non-growth-associated PHB production was triggered by applying nitrogen limitation. The occurrence of some growth-associated PHB production besides non-growth-associated PHB production was demonstrated, although it is inhibited in the presence of nitrogen. Other phenomena observed experimentally and described by the model included biomass growth on PHB and non-linear product inhibition of PHB production. The accumulated impurities from the waste substrate negatively affected the obtained maximum PHB content. Overall, the developed mathematical model provided an accurate prediction of the dynamic behavior of heterotrophic biomass growth and PHB production in a two-phase pure culture system. PMID:24457311

  18. The formation of blobs from a pure interchange process

    SciTech Connect

    Zhu, P.; Sovinec, C. R.; Hegna, C. C.

    2015-02-15

    In this work, we focus on examining a pure interchange process in a shear-less slab configuration as a prototype mechanism for blob formation. We employ full magnetohydrodynamic simulations to demonstrate that the blob-like structures can emerge through the nonlinear development of a pure interchange instability originating from a pedestal-like transition region. In the early nonlinear stage, filamentary structures develop and extend in the direction of the effective gravity. The blob-like structures appear when the radially extending filaments break off and disconnect from the core plasma. The morphology and the dynamics of these filaments and blobs vary dramatically with a sensitive dependence on the dissipation mechanisms in the system and the initial perturbation. Despite the complexity in morphology and dynamics, the nature of the entire blob formation process in the shear-less slab configuration remains strictly interchange without involving any change in magnetic topology.

  19. Assessment of semen quality in pure and crossbred Jersey bulls

    PubMed Central

    Kumar, Umesh; Gawande, Ajay P.; Sahatpure, Sunil K.; Patil, Manoj S.; Lakde, Chetan K.; Bonde, Sachin W.; Borkar, Pradnyankur L.; Poharkar, Ajay J.; Ramteke, Baldeo R.

    2015-01-01

    Aim: To compare the seminal attributes of neat, pre-freeze (at equilibration), and post-freeze (24 h after freezing) semen in pure and crossbred Jersey bulls. Materials and Methods: Total 36 ejaculates (3 ejaculates from each bull) were collected from 6 pure Jersey and 6 crossbred Jersey bulls and evaluated for various seminal attributes during neat, pre-freeze, and post-freeze semen. Results: The mean (±standard error [SE]) values of neat semen characteristics in pure and crossbred Jersey bulls were recorded such as volume (ml), color, consistency, mass activity (scale: 0-5), and sperm concentration (millions/ml). The extended semen was further investigated at pre-freeze and post-freeze stages and the mean (±SE) values recorded at neat, pre-freeze, and post-freeze semen were compared between pure and crossbred Jersey bulls; sperm motility (80.55±1.70%, 62.77±1.35%, 46.11±1.43% vs. 80.00±1.80%, 65.00±1.66%, 47.22±1.08%), live sperm count (83.63±1.08%, 71.72±1.09%, 58.67±1.02% vs. 80.00±1.08%, 67.91±1.20%, 51.63±0.97%), total abnormal sperm count (8.38±0.32%, 12.30±0.39%, 16.75±0.42% vs. 9.00±0.45%, 12.19±0.48%, 18.11±0.64%), hypo-osmotic swelling (HOS) reacted spermatozoa (71.88±0.77%, 62.05±0.80%, 47.27±1.05% vs. 72.77±1.02%, 62.11±0.89%, 45.94±1.33%), acrosome integrity (89.05±0.83%, 81.33±0.71%, 71.94±0.86% vs. 86.55±0.57%, 78.66±0.42%, 69.38±0.53%), and DNA integrity (99.88±0.07%, 100, 99.66±0.11% vs. 99.94±0.05%, 100, 99.44±0.18%,). The volume, color, consistency, sperm concentration, and initial motility in pure and crossbred Jersey bulls did not differ significantly (p>0.05). The mass activity was significantly (p<0.05) higher in pure Jersey as compare to crossbred Jersey bulls. Live sperm percentage and acrosome integrity was significantly (p<0.01) higher in pure Jersey bulls as compared to crossbred Jersey bulls. However, no statistical difference (p>0.05) was observed in abnormal sperm; HOS reacted spermatozoa and DNA

  20. Structure and properties of rapidly solidified pure tin

    NASA Astrophysics Data System (ADS)

    El-Ashram, T.

    2006-03-01

    A comparison has been made between rapidly solidified (RS) pure Sn using melt-spinning technique and Sn produced by conventional casting, using X-ray diffraction (XRD) analysis, differential thermal analysis (DTA), temperature dependence of resistivity (TDR), density measurement and the dynamical resonance method (DRM) for measuring Young's modulus and internal friction. From the XRD and density measurement, it is found that high concentration of vacancies is present in pure Sn RS, the vacancy concentration is found to be 7x10(-3) . From the DTA measurements, we know that there is an increase in the thermodynamic functions such as enthalpy (Delta H), entropy (Delta S) and free energy (Delta G), and also, there is a decrease in the melting temperature. From the TDR results it follows that the resistivity at room temperature is increased and the temperature coefficient of resistivity is decreased. Finally, DRM results show that Young's modulus is decreased and the internal friction is increased.

  1. Control aspects of quantum computing using pure and mixed states

    PubMed Central

    Schulte-Herbrüggen, Thomas; Marx, Raimund; Fahmy, Amr; Kauffman, Louis; Lomonaco, Samuel; Khaneja, Navin; Glaser, Steffen J.

    2012-01-01

    Steering quantum dynamics such that the target states solve classically hard problems is paramount to quantum simulation and computation. And beyond, quantum control is also essential to pave the way to quantum technologies. Here, important control techniques are reviewed and presented in a unified frame covering quantum computational gate synthesis and spectroscopic state transfer alike. We emphasize that it does not matter whether the quantum states of interest are pure or not. While pure states underly the design of quantum circuits, ensemble mixtures of quantum states can be exploited in a more recent class of algorithms: it is illustrated by characterizing the Jones polynomial in order to distinguish between different (classes of) knots. Further applications include Josephson elements, cavity grids, ion traps and nitrogen vacancy centres in scenarios of closed as well as open quantum systems. PMID:22946034

  2. The value of mortality risk reductions. Pure altruism - a confounder?

    PubMed

    Gyrd-Hansen, Dorte; Kjær, Trine; Seested Nielsen, Jytte

    2016-09-01

    This paper examines public valuations of mortality risk reductions. We set up a theoretical framework that allows for altruistic preferences, and subsequently test theoretical predictions through the design of a discrete choice experiment. By varying the tax scenario (uniform versus individual tax), the experimental design allows us to verify whether pure altruistic preferences are present and the underlying causes. We find evidence of negative pure altruism. Under a coercive uniform tax system respondents lower their willingness to pay possibly to ensure that they are not forcing others to pay at a level that corresponds to their own - higher - valuations. This hypothesis is supported by the observation that respondents perceive other individuals' valuations to be lower than their own. Our results suggest that public valuations of mortality risk reductions may underestimate the true societal value because respondents are considering other individuals' welfare, and wrongfully perceive other people's valuations to be low. PMID:27494571

  3. Carboranylphosphinic Acids: A New Class of Purely Inorganic Ligands.

    PubMed

    Oleshkevich, Elena; Teixidor, Francesc; Choquesillo-Lazarte, Duane; Sillanpää, Reijo; Viñas, Clara

    2016-03-01

    Purely inorganic carboranyl phosphinates were prepared, and the influence of the cluster on the reactivity of the phosphinate group was studied. Electron-withdrawal by the carboranyl carbon atoms, combined with space-filling efficiency and enhanced aromaticity of the cluster cage, renders the phosphorus more difficult to oxidize. This enables carboranyl phosphinates to survive harsh oxidizing conditions, a property which is uncommon in organic phosphinates. PMID:26638876

  4. Pure versus hybrid: performance implications of Porter's generic strategies.

    PubMed

    Kumar, K; Subramanian, R; Yauger, C

    1997-01-01

    This article identifies the strategic types in the hospital industry based on the hospital's use of Porter's generic strategies in their pure and hybrid forms. The article also examines differences in performance of hospitals across strategic types. Results indicate that hospitals that follow a focussed cost leadership strategy, in general, have superior performance on a variety of performance measures, while hospitals that use a combination of cost leadership and differentiation perform the poorest. Implications of findings for hospital administrators are also discussed.

  5. Pure Lovelock gravity and Chern-Simons theory

    NASA Astrophysics Data System (ADS)

    Concha, P. K.; Durka, R.; Inostroza, C.; Merino, N.; Rodríguez, E. K.

    2016-07-01

    We explore the possibility of finding pure Lovelock gravity as a particular limit of a Chern-Simons action for a specific expansion of the AdS algebra in odd dimensions. We derive in detail this relation at the level of the action in five and seven dimensions. We provide a general result for higher dimensions and discuss some issues arising from the obtained dynamics.

  6. Nonlocality in pure and mixed n-qubit X states

    NASA Astrophysics Data System (ADS)

    Batle, J.; Ooi, C. H. Raymond; Farouk, Ahmed; Abdalla, S.

    2016-04-01

    Nonlocality for general multiqubit X states is studied in detail. Pure and mixed states are analyzed as far as their maximum amount of nonlocality is concerned, and analytic results are obtained for important families of these states. The particular form of nonzero diagonal and antidiagonal matrix elements makes the corresponding study easy enough to obtain exact results. We also provide a numerical recipe to randomly generate an important family of X states endowed with a given degree of mixture.

  7. Pure subrings of the rings Z{sub {chi}}

    SciTech Connect

    Tsarev, Andrei V

    2009-10-31

    Pure subrings of finite rank in the Z-adic completion of the ring of integers and in its homomorphic images are considered. Certain properties of these rings are studied (existence of an identity element, decomposability into a direct sum of essentially indecomposable ideals, condition for embeddability into a csp-ring, etc.). Additive groups of these rings and conditions under which these rings are subrings of algebraic number fields are described. Bibliography: 12 titles.

  8. Pure closed posteromedial dislocation of the tibiotalar joint without fracture.

    PubMed

    Wang, Yun-tao; Wu, Xiao-tao; Chen, Hui

    2013-08-01

    Pure tibiotalar dislocation without an associated fracture is an extremely rare injury. We present three cases of closed posteromedial tibiotalar dislocation without any associated fractures to the foot, ankle, or leg. All patients were treated conservatively with immediate closed reduction under general or local anaesthesia and immobilised in a short leg cast for six weeks without weight-bearing resulting in a satisfactory outcome at the final follow-up. A review of the literature is also presented in this paper.

  9. Direct exfoliation and dispersion of two-dimensional materials in pure water via temperature control

    PubMed Central

    Kim, Jinseon; Kwon, Sanghyuk; Cho, Dae-Hyun; Kang, Byunggil; Kwon, Hyukjoon; Kim, Youngchan; Park, Sung O.; Jung, Gwan Yeong; Shin, Eunhye; Kim, Wan-Gu; Lee, Hyungdong; Ryu, Gyeong Hee; Choi, Minseok; Kim, Tae Hyeong; Oh, Junghoon; Park, Sungjin; Kwak, Sang Kyu; Yoon, Suk Wang; Byun, Doyoung; Lee, Zonghoon; Lee, Changgu

    2015-01-01

    The high-volume synthesis of two-dimensional (2D) materials in the form of platelets is desirable for various applications. While water is considered an ideal dispersion medium, due to its abundance and low cost, the hydrophobicity of platelet surfaces has prohibited its widespread use. Here we exfoliate 2D materials directly in pure water without using any chemicals or surfactants. In order to exfoliate and disperse the materials in water, we elevate the temperature of the sonication bath, and introduce energy via the dissipation of sonic waves. Storage stability greater than one month is achieved through the maintenance of high temperatures, and through atomic and molecular level simulations, we further discover that good solubility in water is maintained due to the presence of platelet surface charges as a result of edge functionalization or intrinsic polarity. Finally, we demonstrate inkjet printing on hard and flexible substrates as a potential application of water-dispersed 2D materials. PMID:26369895

  10. Direct exfoliation and dispersion of two-dimensional materials in pure water via temperature control.

    PubMed

    Kim, Jinseon; Kwon, Sanghyuk; Cho, Dae-Hyun; Kang, Byunggil; Kwon, Hyukjoon; Kim, Youngchan; Park, Sung O; Jung, Gwan Yeong; Shin, Eunhye; Kim, Wan-Gu; Lee, Hyungdong; Ryu, Gyeong Hee; Choi, Minseok; Kim, Tae Hyeong; Oh, Junghoon; Park, Sungjin; Kwak, Sang Kyu; Yoon, Suk Wang; Byun, Doyoung; Lee, Zonghoon; Lee, Changgu

    2015-09-15

    The high-volume synthesis of two-dimensional (2D) materials in the form of platelets is desirable for various applications. While water is considered an ideal dispersion medium, due to its abundance and low cost, the hydrophobicity of platelet surfaces has prohibited its widespread use. Here we exfoliate 2D materials directly in pure water without using any chemicals or surfactants. In order to exfoliate and disperse the materials in water, we elevate the temperature of the sonication bath, and introduce energy via the dissipation of sonic waves. Storage stability greater than one month is achieved through the maintenance of high temperatures, and through atomic and molecular level simulations, we further discover that good solubility in water is maintained due to the presence of platelet surface charges as a result of edge functionalization or intrinsic polarity. Finally, we demonstrate inkjet printing on hard and flexible substrates as a potential application of water-dispersed 2D materials.

  11. Direct exfoliation and dispersion of two-dimensional materials in pure water via temperature control.

    PubMed

    Kim, Jinseon; Kwon, Sanghyuk; Cho, Dae-Hyun; Kang, Byunggil; Kwon, Hyukjoon; Kim, Youngchan; Park, Sung O; Jung, Gwan Yeong; Shin, Eunhye; Kim, Wan-Gu; Lee, Hyungdong; Ryu, Gyeong Hee; Choi, Minseok; Kim, Tae Hyeong; Oh, Junghoon; Park, Sungjin; Kwak, Sang Kyu; Yoon, Suk Wang; Byun, Doyoung; Lee, Zonghoon; Lee, Changgu

    2015-01-01

    The high-volume synthesis of two-dimensional (2D) materials in the form of platelets is desirable for various applications. While water is considered an ideal dispersion medium, due to its abundance and low cost, the hydrophobicity of platelet surfaces has prohibited its widespread use. Here we exfoliate 2D materials directly in pure water without using any chemicals or surfactants. In order to exfoliate and disperse the materials in water, we elevate the temperature of the sonication bath, and introduce energy via the dissipation of sonic waves. Storage stability greater than one month is achieved through the maintenance of high temperatures, and through atomic and molecular level simulations, we further discover that good solubility in water is maintained due to the presence of platelet surface charges as a result of edge functionalization or intrinsic polarity. Finally, we demonstrate inkjet printing on hard and flexible substrates as a potential application of water-dispersed 2D materials. PMID:26369895

  12. Idealization in Chemistry: Pure Substance and Laboratory Product

    NASA Astrophysics Data System (ADS)

    Fernández-González, Manuel

    2013-07-01

    This article analyzes the concept of idealization in chemistry and the role played by pure substance and laboratory product. This topic has evident repercussions in the educational contexts that are applied to the science classroom, which are highlighted throughout the text. A common structure for knowledge construction is proposed for both physics and chemistry with particular emphasis on the relations between two of the levels: the ideal level and the quasi-ideal level. The ideal level is crucial for operations related to theoretical constructions and explanations, whereas the quasi-ideal level is of special importance in the verification of propositions. In chemistry, the ideal level and the quasi-ideal level include the entities, pure substance and laboratory product, respectively. This article provides an in-depth discussion of the concept of pure substance, an idealized entity whose empirical correlate is laboratory product. The study of the link between the two is a very significant part of the problem of the relations between theory and reality in chemistry. These entities are used to analyze and interpret different situations and contexts in research as well as teaching. The article concludes by using classroom examples to illustrate the didactic implications of the issues addressed.

  13. Ligands Slow Down Pure-Dephasing in Semiconductor Quantum Dots.

    PubMed

    Liu, Jin; Kilina, Svetlana V; Tretiak, Sergei; Prezhdo, Oleg V

    2015-09-22

    It is well-known experimentally and theoretically that surface ligands provide additional pathways for energy relaxation in colloidal semiconductor quantum dots (QDs). They increase the rate of inelastic charge-phonon scattering and provide trap sites for the charges. We show that, surprisingly, ligands have the opposite effect on elastic electron-phonon scattering. Our simulations demonstrate that elastic scattering slows down in CdSe QDs passivated with ligands compared to that in bare QDs. As a result, the pure-dephasing time is increased, and the homogeneous luminescence line width is decreased in the presence of ligands. The lifetime of quantum superpositions of single and multiple excitons increases as well, providing favorable conditions for multiple excitons generation (MEG). Ligands reduce the pure-dephasing rates by decreasing phonon-induced fluctuations of the electronic energy levels. Surface atoms are most mobile in QDs, and therefore, they contribute greatly to the electronic energy fluctuations. The mobility is reduced by interaction with ligands. A simple analytical model suggests that the differences between the bare and passivated QDs persist for up to 5 nm diameters. Both low-frequency acoustic and high-frequency optical phonons participate in the dephasing processes in bare QDs, while low-frequency acoustic modes dominate in passivated QDs. The theoretical predictions regarding the pure-dephasing time, luminescence line width, and MEG can be verified experimentally by studying QDs with different surface passivation. PMID:26284384

  14. Metastable growth of pure wurtzite InGaAs microstructures.

    PubMed

    Ng, Kar Wei; Ko, Wai Son; Lu, Fanglu; Chang-Hasnain, Connie J

    2014-08-13

    III-V compound semiconductors can exist in two major crystal phases, namely, zincblende (ZB) and wurtzite (WZ). While ZB is thermodynamically favorable in conventional III-V epitaxy, the pure WZ phase can be stable in nanowires with diameters smaller than certain critical values. However, thin nanowires are more vulnerable to surface recombination, and this can ultimately limit their performances as practical devices. In this work, we study a metastable growth mechanism that can yield purely WZ-phased InGaAs microstructures on silicon. InGaAs nucleates as sharp nanoneedles and expand along both axial and radial directions simultaneously in a core-shell fashion. While the base can scale from tens of nanometers to over a micron, the tip can remain sharp over the entire growth. The sharpness maintains a high local surface-to-volume ratio, favoring hexagonal lattice to grow axially. These unique features lead to the formation of microsized pure WZ InGaAs structures on silicon. To verify that the WZ microstructures are truly metastable, we demonstrate, for the first time, the in situ transformation from WZ to the energy-favorable ZB phase inside a transmission electron microscope. This unconventional core-shell growth mechanism can potentially be applied to other III-V materials systems, enabling the effective utilization of the extraordinary properties of the metastable wurtzite crystals.

  15. Behavior of pure gallium in water and various saline solutions.

    PubMed

    Horasawa, N; Nakajima, H; Takahashi, S; Okabe, T

    1997-12-01

    This study investigated the chemical stability of pure gallium in water and saline solutions in order to obtain fundamental knowledge about the corrosion mechanism of gallium-based alloys. A pure gallium plate (99.999%) was suspended in 50 mL of deionized water, 0.01%, 0.1% or 1% NaCl solution at 24 +/- 2 degrees C for 1, 7, or 28 days. The amounts of gallium released into the solutions were determined by atomic absorption spectrophotometry. The surfaces of the specimens were examined after immersion by x-ray diffractometry (XRD) and x-ray photoelectron spectroscopy (XPS). In the solutions containing 0.1% or more NaCl, the release of gallium ions into the solution was lowered when compared to deionized water after 28-day immersion. Gallium oxide monohydroxide was found by XRD on the specimens immersed in deionized water after 28-day immersion. XPS indicated the formation of gallium oxide/hydroxide on the specimens immersed in water or 0.01% NaCl solution. The chemical stability of pure solid gallium was strongly affected by the presence of Cl- ions in the aqueous solution.

  16. Feasibility of purely endoscopic intramedullary fixation of mandibular condyle fractures.

    PubMed

    Frake, Paul C; Goodman, Joseph F; Joshi, Arjun S

    2015-01-01

    The investigators of this study hypothesized that fractures of the mandibular condyle can be repaired using short-segment intramedullary implants and purely endoscopic surgical technique, using a basic science, human cadaver model in an academic center. Endoscopic instrumentation was used through a transoral mucosal incision to place intramedullary implants of 2 cm in length into osteotomized mandibular condyles. The surgical maneuvers that required to insert these implants, including condyle positioning, reaming, implant insertion, and seating of the mandibular ramus, are described herein. Primary outcome was considered as successful completion of the procedure. Ten cadaveric mandibular condyles were successfully repaired with rigid intramedullary internal fixation without the use of external incisions. Both insertion of a peg-type implant and screwing a threaded implant into the condylar head were possible. The inferior portion of the implant remained exposed, and the ramus of the mandible was manipulated into position on the implant using retraction at the sigmoid notch. The results of this study suggest that purely endoscopic repair of fractures of the mandibular condyle is possible by using short-segment intramedullary titanium implants and a transoral endoscopic approach without the need for facial incisions or punctures. The biomechanical advantages of these intramedullary implants, including improved strength and resistance to mechanical failure compared with miniplates, have been recently established. The combination of improved implant design and purely endoscopic technique may allow for improved fixation and reduced surgical- and implant-related morbidity in the treatment of condylar fractures. PMID:25534058

  17. The Temperature Dependent Enthalpy of Vaporization of Pure Substances

    NASA Astrophysics Data System (ADS)

    Tian, Jianxiang

    Recently the universal behavior of the temperature dependent enthalpy of vaporization along with the whole liquid-vapor coexistence curve at equilibrium is described and explained by Roman et al.5 The work (called RWVM relation) succeeds in the combination of the linear relation near the triple point and the renormalization group theory result near the critical point. For the convenience of chemical designs and engineering applications, we report its b values yielding the minimum average absolute deviation (AAD) for 74 pure substances from the NIST web-book and compare the results with other correlations. We find that with an adapted b value, the RWVM relation predicts the data of 47 pure substances with an AAD less than 0.0093, with six more than 0.02 and all less than 0.03 except quantum fluid hydrogen, that is clearly better than other correlations. For most pure substances, b covers the range from 0 to 1. Only one negative value stands for the quantum fluid helium because of its enthalpy of vaporization being experimentally not a monotonic function of the temperature in the range near the triple point.

  18. Split-Hopkinson Pressure Bar Tests on Pure Tantalum

    NASA Astrophysics Data System (ADS)

    Dick, Richard D.; Armstrong, Ronald W.

    1997-07-01

    Pure tantalum was loaded in compression by a split-Hopkinson pressure bar (SHPB) apparatus to strain rates from 450 to 6350 s-1. These stress-strain data were added to data collected previously to evaluate and improve the constitutive equations for tantalum(Armstrong, et al., 1997, Final report to the U.S. Army Research Laboratory, Aberdeen Proving Ground, MD.). In particular, the high strain rate data were compared to SHPB data of Armstrong, et al.(Armstrong, et al., 1997, Tantalum, Published by Minerals, Metals, and Mining Society, Warrendale, PA.) for commercially prepared tantalum. The main conclusions are: 1) the flow stress - log strain rate data agree well with the Zerilli - Armstrong constitutive model for pure tantalum, 2) uniform strain exponents computed for pure tantalum are significantly smaller than for commercial tantalum relating to the presence of impurities, 3) a plot of the uniform strain exponent versus log strain rate shows good agreement with the curve predicted by Zerilli and Armstrong at strain rates above 2000 s-1, and 4) the ductility of commercial tantalum is enhanced at high strain rates because of added dislocation generation.

  19. Path integral regularization of pure Yang-Mills theory

    SciTech Connect

    Jacquot, J. L.

    2009-07-15

    In enlarging the field content of pure Yang-Mills theory to a cutoff dependent matrix valued complex scalar field, we construct a vectorial operator, which is by definition invariant with respect to the gauge transformation of the Yang-Mills field and with respect to a Stueckelberg type gauge transformation of the scalar field. This invariant operator converges to the original Yang-Mills field as the cutoff goes to infinity. With the help of cutoff functions, we construct with this invariant a regularized action for the pure Yang-Mills theory. In order to be able to define both the gauge and scalar fields kinetic terms, other invariant terms are added to the action. Since the scalar fields flat measure is invariant under the Stueckelberg type gauge transformation, we obtain a regularized gauge-invariant path integral for pure Yang-Mills theory that is mathematically well defined. Moreover, the regularized Ward-Takahashi identities describing the dynamics of the gauge fields are exactly the same as the formal Ward-Takahashi identities of the unregularized theory.

  20. Analysis of Ultra-Pure Gases by Ion Mobility Spectrometry

    NASA Technical Reports Server (NTRS)

    Stimac, Robert M.; Wernlund, Roger F.; Cohen, Martin J.

    1995-01-01

    Work has continued with the evaluation of the Ion Mobility Spectrometer (IMS) for the analysis of gases having low parts-per-billion (10(exp -9)) water concentration. A modified PCP, inc. MMS-160 Mobility Mass Spectrometer System was used for the analysis of ultra-pure argon and nitrogen. The MMS-160 system permits the mass-identification of unique reactant and product ions observed in the reduced-water host gases. When the water is removed to low ppb levels, higher energy reactant ions are observed. In nitrogen, distinct odd- and even-numbered nitrogen cluster ion mobility peaks are observed, as well as adduct ion peaks from the trace contaminants in the gas. Argon also produces a cluster ion mobility peak and adduct ion peaks from trace components in the gas. Levels of contaminants in these ultra-pure gases can be determined from the ion mobility spectra. A calibrated source was used to provide variable known quantities of water to the pure gas supply of the IMS.

  1. Angels and demons are among us: assessing individual differences in belief in pure evil and belief in pure good.

    PubMed

    Webster, Russell J; Saucier, Donald A

    2013-11-01

    We conducted five studies to demonstrate that individuals' beliefs in pure evil (BPE) and in pure good (BPG) are valid and important psychological constructs. First, these studies together demonstrated that BPE and BPG are reliable, unitary, and stable constructs each composed of eight theoretically interdependent dimensions. Second, these studies showed that across a wide variety of different measures, higher BPE consistently related to greater intergroup aggression (e.g., supporting the death penalty and preemptive military aggression) and less intergroup prosociality (e.g., opposing criminal rehabilitation, proracial policies, and beneficial social programs), while higher BPG consistently related to less intergroup aggression (e.g., opposing proviolent foreign relations and torture) and greater intergroup prosociality (e.g., supporting criminal rehabilitation and support for diplomacy). In sum, these studies evidence that BPE and BPG relate to aggressive and prosocial orientations toward others and have strong potential to advance current theories on prejudice, aggression, and prosociality.

  2. Angels and demons are among us: assessing individual differences in belief in pure evil and belief in pure good.

    PubMed

    Webster, Russell J; Saucier, Donald A

    2013-11-01

    We conducted five studies to demonstrate that individuals' beliefs in pure evil (BPE) and in pure good (BPG) are valid and important psychological constructs. First, these studies together demonstrated that BPE and BPG are reliable, unitary, and stable constructs each composed of eight theoretically interdependent dimensions. Second, these studies showed that across a wide variety of different measures, higher BPE consistently related to greater intergroup aggression (e.g., supporting the death penalty and preemptive military aggression) and less intergroup prosociality (e.g., opposing criminal rehabilitation, proracial policies, and beneficial social programs), while higher BPG consistently related to less intergroup aggression (e.g., opposing proviolent foreign relations and torture) and greater intergroup prosociality (e.g., supporting criminal rehabilitation and support for diplomacy). In sum, these studies evidence that BPE and BPG relate to aggressive and prosocial orientations toward others and have strong potential to advance current theories on prejudice, aggression, and prosociality. PMID:23885037

  3. Fabrication of Powder Metallurgy Pure Ti Material by Using Thermal Decomposition of TiH2

    NASA Astrophysics Data System (ADS)

    Mimoto, Takanori; Nakanishi, Nozomi; Umeda, Junko; Kondoh, Katsuyoshi

    Titanium (Ti) and titanium alloys have been interested as an engineering material because they are widely used across various industrial applications, for example, motorcycle, automotive and aerospace industries, due to their light weight, high specific strength and superior corrosion resistance. Ti materials are particularly significant for the aircraft using carbon/carbon (C/C) composites, for example, carbon fiber reinforced plastics (CFRP), because Ti materials are free from the problem of contact corrosion between C/C composites. However, the applications of Ti materials are limited because of their high cost. From a viewpoint of cost reduction, cost effective process to fabricate Ti materials is strongly required. In the present study, the direct consolidation of titanium hydride (TiH2) raw powders in solid-state was employed to fabricate pure Ti bulk materials by using thermal decomposition of TiH2. In general, the production cost of Ti components is expensive due to using commercially pure (CP) Ti powders after dehydrogenation. On the other hand, the novel process using TiH2 powders as starting materials is a promising low cost approach for powder metallurgy (P/M) Ti products. Furthermore, this new process is also attractive from a viewpoint of energy saving because the dehydrogenation is integrated into the sintering process. In this study, TiH2 raw powders were directly consolidated by conventional press technique at 600 MPa to prepare TiH2 powder compacted billets. To thermally decompose TiH2 and obtain sintered pure Ti billets, the TiH2 powder billets were heated in the integrated sintering process including dehydrogenation. The hot-extruded pure Ti material, which was heat treated at 1273 K for 180 min in argon gas atmosphere, showed tensile strength of 701.8 MPa and elongation of 27.1%. These tensile properties satisfied the requirements for JIS Ti Grade 4. The relationship between microstructures, mechanical properties response and heat treatment

  4. Strength tests of thin-walled elliptic duralumin cylinders in pure bending and in combined pure bending and torsion

    NASA Technical Reports Server (NTRS)

    Lundquist, Eugene E; Stowell, Elbridge Z

    1942-01-01

    An analysis is presented of the results of tests made by the Massachusetts Institute of Technology and by the National Advisory Committee for Aeronautics on an investigation of the strength of thin-walled circular and elliptic cylinders in pure bending and in combined torsion and bending. In each of the loading conditions, the bending moments were applied in the plane of the major axis of the ellipse.

  5. Low dose irradiation creep of pure nickel. [17 or 15 MeV deuterons

    SciTech Connect

    Henager, C.H. Jr.

    1984-10-01

    A detailed climb-controlled glide model of low dose irradiation creep has been developed to rationalize irradiation creep data of pure nickel irradiated in a light ion irradiation creep apparatus. Experimental irradiation creep data were obtained to study the effects of initial microstructure and stress on low dose irradiation creep in pure nickel. Pure nickel specimens (99.992% Ni), with three different microstructures, were irradiated with 17 or 15 MeV deuterons at 473 K and stresses ranging from 0.35 to 0.9 of the unirradiated yield stress. Transmission electron microscopy revealed that the microstructure following irradiation to 0.05 dpa consisted of a high density of small dislocation loops, some small voids and network dislocations. The creep model predicted creep rates proportional to the mobile dislocation density and a comparison of experimental irradiation creep rates as a function of homologous stress revealed a dependence on initial microstructure of the magnitude predicted by the measured dislocation densities. The three microstructures that were irradiated consisted of 85% and 25% cold-worked Ni specimens and well-annealed Ni specimens. A weak stress dependence of irradiation creep was observed in 85% cold-worked Ni in agreement with experimental determinations of the stress dependence of irradiation creep by others. The weak stress dependence was shown to be a consequence of the stress independence of the dislocation climb velocity and the weak stress dependence of the barrier removal process. The irradiation creep rate was observed to be proportional to the applied stress. This linear stress dependence was suggested to be due to the stress dependence of the mobile dislocation density. 101 references, 27 figures, 11 tables.

  6. Methyl tunnelling in pure and matrix isolated halogenomesitylenes

    NASA Astrophysics Data System (ADS)

    Meinnel, J.; Mani, M.; Nusimovici, M.; Carlile, C. J.; Hennion, B.; Carrié, R.; Wyncke, B.; Sanquer, M.; Tonnard, F.

    1994-10-01

    The trihalogenomesitylenes, C 6(CH 3) 3X 3, where X = Cl, Br, I crystallise in the triclinic P overline1 space- group, such that the three methyl groups in one molecule see different environments. Indeed, we have detected three tunnelling and three torsional transitions in the pure compounds. In the case of a 3.7% mixture of protonated tribromomesitylene in a matrix of hexabromobenzene, we have detected only one tunnelling transition at 102μeV; from this, we conclude that the three methyl groups of the TBM molecule in the dilute mixture are equivalent in what is a relatively symmetrical environment and as a consequence also in the isolated molecule. A solid solution of 6% fully protonated trichloromesitylene in a matrix of fully deuterated TCM gives three transitions similar to those in the pure compound, indicating that there is no strong coupling between the different methyl groups. We also present Raman and FIR spectra of pure TBM giving the phonon frequencies at the Γ point. Some IR absorption maxima fall near maxima of the neutron spectra, indicating coupling between some phonons and the torsional transitions. So as to give us a model of the tribromomesitylene system we have optimised atom-atom Buckingham-type coefficients so as to reproduce the experimental phonon frequencies. The coefficients were used to calculate the intermolecular contribution Vex(θ) to Vs(θ), the potential hindering the methyl groups. The intramolecular contribution Vin(θ) was found using the quantum chemistry program AM1. The total hindering potential Vs(θ) so obtained allowed us to calculate the principal dynamic features of the methyl rotors in reasonable agreement with the experiments.

  7. Super-Maxwellian helium evaporation from pure and salty water

    NASA Astrophysics Data System (ADS)

    Hahn, Christine; Kann, Zachary R.; Faust, Jennifer A.; Skinner, J. L.; Nathanson, Gilbert M.

    2016-01-01

    Helium atoms evaporate from pure water and salty solutions in super-Maxwellian speed distributions, as observed experimentally and modeled theoretically. The experiments are performed by monitoring the velocities of dissolved He atoms that evaporate from microjets of pure water at 252 K and 4-8.5 molal LiCl and LiBr at 232-252 K. The average He atom energies exceed the flux-weighted Maxwell-Boltzmann average of 2RT by 30% for pure water and 70% for 8.5m LiBr. Classical molecular dynamics simulations closely reproduce the observed speed distributions and provide microscopic insight into the forces that eject the He atoms from solution. Comparisons of the density profile and He kinetic energies across the water-vacuum interface indicate that the He atoms are accelerated by He-water collisions within the top 1-2 layers of the liquid. We also find that the average He atom kinetic energy scales with the free energy of solvation of this sparingly soluble gas. This free-energy difference reflects the steeply decreasing potential of mean force on the He atoms in the interfacial region, whose gradient is the repulsive force that tends to expel the atoms. The accompanying sharp decrease in water density suppresses the He-water collisions that would otherwise maintain a Maxwell-Boltzmann distribution, allowing the He atom to escape at high energies. Helium is especially affected by this reduction in collisions because its weak interactions make energy transfer inefficient.

  8. Probabilistically Perfect Cloning of Two Pure States: Geometric Approach

    NASA Astrophysics Data System (ADS)

    Yerokhin, V.; Shehu, A.; Feldman, E.; Bagan, E.; Bergou, J. A.

    2016-05-01

    We solve the long-standing problem of making n perfect clones from m copies of one of two known pure states with minimum failure probability in the general case where the known states have arbitrary a priori probabilities. The solution emerges from a geometric formulation of the problem. This formulation reveals that cloning converges to state discrimination followed by state preparation as the number of clones goes to infinity. The convergence exhibits a phenomenon analogous to a second-order symmetry-breaking phase transition.

  9. Cooperative pulses for pseudo-pure state preparation

    NASA Astrophysics Data System (ADS)

    Wei, Daxiu; Chang, Yan; Glaser, Steffen J.; Yang, Xiaodong

    2014-06-01

    Using an extended version of the optimal-control-based gradient ascent pulse engineering algorithm, cooperative (COOP) pulses are designed for multi-scan experiments to prepare pseudo-pure states in quantum computation. COOP pulses can cancel undesired signal contributions, complementing and generalizing phase cycles. They also provide more flexibility and, in particular, eliminate the need to select specific individual target states and achieve the fidelity of theoretical limit by flexibly choosing appropriate number of scans and duration of pulses. The COOP approach is experimentally demonstrated for three-qubit and four-qubit systems.

  10. Superconductor—Insulator Transitions in Pure Polycrystalline Nb Thin Films

    NASA Astrophysics Data System (ADS)

    Couedo, F.; Crauste, O.; Bergé, L.; Dolgorouky, Y.; Marrache-Kikuchi, C.; Dumoulin, L.

    2012-12-01

    We report on a study of the transport properties of Nb thin films. By varying the thickness of the films from 263 Å to 25 Å, we observed a depression of the superconductivity. Magnetic field was also applied up to 6 T, inducing the disappearance of the superconductivity and the onset of an insulating behavior. The results were compared to those we have already obtained on a highly disordered system, a-NbxSi1-x, to understand whether the same mechanisms for the disappearance of the superconductivity could be at play in pure metallic thin films and in highly disordered systems.

  11. Multiboson Correlation Interferometry with Arbitrary Single-Photon Pure States.

    PubMed

    Tamma, Vincenzo; Laibacher, Simon

    2015-06-19

    We provide a compact full description of multiboson correlation measurements of arbitrary order N in passive linear interferometers with arbitrary input single-photon pure states. This allows us to physically analyze the novel problem of multiboson correlation sampling at the output of random linear interferometers. Our results also describe general multiboson correlation landscapes for an arbitrary number of input single photons and arbitrary interferometers. In particular, we use two different schemes to demonstrate, respectively, arbitrary-order quantum beat interference and 100% visibility entanglement correlations even for input photons distinguishable in their frequencies. PMID:26196976

  12. MONOPOLES AND DYONS IN THE PURE EINSTEIN YANG MILLS THEORY

    SciTech Connect

    HOSOTANI,Y.; BJORAKER,J.

    1999-08-16

    In the pure Einstein-Yang-Mills theory in four dimensions there exist monopole and dyon solutions. The spectrum of the solutions is discrete in asymptotically flat or de Sitter space, whereas it is continuous in asymptotically anti-de Sitter space. The solutions are regular everywhere and specified with their mass, and non-Abelian electric and magnetic charges. In asymptotically anti-de Sitter space a class of monopole solutions have no node in non-Abelian magnetic fields, and are stable against spherically symmetric perturbations.

  13. Emergence of canonical ensembles from pure quantum states.

    PubMed

    Cho, Jaeyoon; Kim, M S

    2010-04-30

    We consider a system weakly interacting with a bath as a thermodynamic setting to establish a quantum foundation of statistical physics. It is shown that even if the composite system is initially in an arbitrary nonequilibrium pure quantum state, the unitary dynamics of a generic weak interaction almost always drives the subsystem into the canonical ensemble, in the usual sense of typicality. A crucial step is taken by assuming that the matrix elements of the interaction Hamiltonian have random phases, while their amplitudes are left unrestricted. PMID:20482093

  14. Cooperative pulses for pseudo-pure state preparation

    SciTech Connect

    Wei, Daxiu; Chang, Yan; Yang, Xiaodong E-mail: xiaodong.yang@sibet.ac.cn; Glaser, Steffen J. E-mail: xiaodong.yang@sibet.ac.cn

    2014-06-16

    Using an extended version of the optimal-control-based gradient ascent pulse engineering algorithm, cooperative (COOP) pulses are designed for multi-scan experiments to prepare pseudo-pure states in quantum computation. COOP pulses can cancel undesired signal contributions, complementing and generalizing phase cycles. They also provide more flexibility and, in particular, eliminate the need to select specific individual target states and achieve the fidelity of theoretical limit by flexibly choosing appropriate number of scans and duration of pulses. The COOP approach is experimentally demonstrated for three-qubit and four-qubit systems.

  15. Infinite tension limit of the pure spinor superstring

    NASA Astrophysics Data System (ADS)

    Berkovits, Nathan

    2014-03-01

    Mason and Skinner recently constructed a chiral infinite tension limit of the Ramond-Neveu-Schwarz superstring which was shown to compute the Cachazo-He-Yuan formulae for tree-level d = 10 Yang-Mills amplitudes and the NS-NS sector of tree-level d = 10 supergravity amplitudes. In this letter, their chiral infinite tension limit is generalized to the pure spinor superstring which computes a d = 10 superspace version of the Cachazo-He-Yuan formulae for tree-level d = 10 super-Yang-Mills and supergravity amplitudes.

  16. Robust calibration method for pure rotational Raman lidar temperature measurement.

    PubMed

    Chen, Hao; Chen, Siying; Zhang, Yinchao; Guo, Pan; Chen, He; Chen, Binglong

    2015-08-10

    A new calibration method for pure rotational Raman lidar temperature measurement is described in this work. The method forms a temperature-dependent term in the intensity ratio, which is calculable with the radiosonde data, and then derives a calibration factor, with which the temperature is retrievable from the lidar return. The method is demonstrated and compared with existing methods through simulations and experiments. Results of the comparison show that the proposed method could provide more accurate calibrations under low signal-to-noise ratio conditions and could thus reduce the lidar performance requirement for temperature retrieval.

  17. Laboratory astrophysics and molecular astronomy of pure carbon molecules.

    PubMed

    Bernath, P F

    1995-03-01

    The pure carbon molecules Cn are currently of great experimental and theoretical interest. Our work in this area begins with detection of the SiC molecule, which is isovalent with C2. New infrared electronic transitions of C2 and C3 were discovered by emission spectroscopy of hydrocarbon dicharges. The C3 and C5 molecules were found by infrared vibration-rotation spectroscopy of the prototypical obscured carbon star, IRC+10216. C7 and C9 were searched for in the same source, but not found. The laboratory infrared emission spectrum of C60 was recorded to aid in a search for C60 in extraterrestrial sources.

  18. Purely lossy and robust quantum interfaces between light and matter.

    PubMed

    Filip, Radim; Klapka, Petr

    2014-12-15

    The commonly used teleportation-based interfaces between light and matter are very sensitive to noise of matter systems and also to the optical in-coupling and out-coupling losses. These imperfections produce classical noise in the teleportation interface, which significantly limits the transmission of quantum states. We propose robust quantum interfaces between weakly coupled continuous variables of light and matter. The state transfer introduces only pure loss, without any additional classical noise, despite a presence of in-coupling and out-coupling optical losses. These interfaces qualitatively overcome commonly used interfaces based on quantum teleportation. PMID:25607017

  19. Monoclonal gammopathy-associated pure red cell aplasia.

    PubMed

    Korde, Neha; Zhang, Yong; Loeliger, Kelsey; Poon, Andrea; Simakova, Olga; Zingone, Adriana; Costello, Rene; Childs, Richard; Noel, Pierre; Silver, Samuel; Kwok, Mary; Mo, Clifton; Young, Neal; Landgren, Ola; Sloand, Elaine; Maric, Irina

    2016-06-01

    Pure red cell aplasia (PRCA) is a rare disorder characterized by inhibition of erythroid precursors in the bone marrow and normochromic, normocytic anaemia with reticulocytopenia. Among 51 PRCA patients, we identified 12 (24%) patients having monoclonal gammopathy, monoclonal gammopathy of undetermined significance or smouldering multiple myeloma, with presence of monoclonal protein or abnormal serum free light chains and atypical bone marrow features of clonal plasmacytosis, hypercellularity and fibrosis. Thus far, three patients treated with anti-myeloma based therapeutics have responded with reticulocyte recovery and clinical transfusion independence, suggesting plasma cells play a key role in the pathogenesis of this specific monoclonal gammopathy-associated PRCA. PMID:26999424

  20. The KTeV Pure CsI Calorimeter

    SciTech Connect

    Ray, R.E.

    1994-12-01

    KTeV is currently building a state-of-the-art pure CsI electromagnetic calorimeter with a sophisticated digital readout. The CsI array is expected to have better than 1% resolution over a dynamic range of 2--64 GeV. The design of the CsI array is driven by the difficult physics goal of attempting to measure the CP violation parameter Re({epsilon}{prime}/{epsilon}) to 1 part in 10000 in a high-rate neutral beam environment. The physics requirements and their impact on the final design will be discussed.

  1. Thermal stability and strength of deformation microstructures in pure copper

    SciTech Connect

    Saldana, C.; King, Alex H.; Chandrasekar, S.

    2012-05-18

    The plastic flow field produced by machining is utilized to access a range of deformation parameters in pure copper: strains of 1–7, strain rates of 1–1000 s−1 and temperatures as low as 77 K. The strength and stability of the severe plastic deformation microstructures including cellular, elongated, equiaxed and twinned types are characterized. Unique combinations of strengthening and stability are identified in the case of heavily twinned microstructures. These observations offer insights for improving the stability of both single-phase and multicomponent ultrafine-grained alloys.

  2. Purely lossy and robust quantum interfaces between light and matter.

    PubMed

    Filip, Radim; Klapka, Petr

    2014-12-15

    The commonly used teleportation-based interfaces between light and matter are very sensitive to noise of matter systems and also to the optical in-coupling and out-coupling losses. These imperfections produce classical noise in the teleportation interface, which significantly limits the transmission of quantum states. We propose robust quantum interfaces between weakly coupled continuous variables of light and matter. The state transfer introduces only pure loss, without any additional classical noise, despite a presence of in-coupling and out-coupling optical losses. These interfaces qualitatively overcome commonly used interfaces based on quantum teleportation.

  3. Entanglement dynamics of spin systems in pure states

    NASA Astrophysics Data System (ADS)

    Furman, G. B.; Meerovich, V. M.; Sokolovsky, V. L.

    2009-09-01

    We investigate numerically the appearance and evolution of entanglement in spin systems prepared initially in a pure state. We consider the dipolar coupling spin systems of different molecular structures: benzene C6H6 , cyclopentane C5H10 , sodium butyrate CH3(CH2)2CO2Na , and calcium hydroxyapatite Ca5(OH)(PO4)3 . Numerical simulations show that the close relationship exists between the intensity of second order (2Q) coherences and concurrences of nearest spins in a cyclopentane molecule.

  4. Dendritic crystal growth in pure /sup 4/He

    SciTech Connect

    Franck, J.P.; Jung, J.

    1986-08-01

    Dendritic crystal growth of pure hcp and fcc /sup 4/He was observed at pressures between 210 and 6500 bar. Dendrite morphology depends on fluid supercooling and crystal phase. At large supercooling, dendrites with side arms are observed, whereas at low supercooling dendrites grow without side arms. The morpholpogy of hcp /sup 4/He dendrites is strongly influenced by crystalline anisotropy. Comparison with present theories of dendrite growth show good agreement with the power law dependencies of velocity, tip radius, and Peclet number on supercooling. Numerically, theory predicts much larger velocities than are observed. The stability parameter sigma is found to be much smaller than theoretically predicted.

  5. Damage Analysis of Rectangular Section Composite Beam under Pure Bending

    NASA Astrophysics Data System (ADS)

    Liu, Yiping; Xiao, Fan; Liu, Zejia; Tang, Liqun; Fang, Daining

    2013-02-01

    Laminated composite beams are commonly used in engineering applications involving macro to nano structures. Based on the assumption that plain sections remain plain after deformation, this paper analyzes stress distributions in cross-ply laminated composite beams with rectangular cross-sections, and formulates the basic damage equations through Kachanov's damage definition and Janson's failure criterion. The location of the neutral axis and the ultimate bending moment are obtained for pure bending cases. The effect of the elastic modulus of the two layers on the damage evolution is analyzed; a reasonable damage composite beam model is proposed to predict the ultimate bending moment.

  6. Pure versus hybrid: performance implications of Porter's generic strategies.

    PubMed

    Kumar, K; Subramanian, R; Yauger, C

    1997-01-01

    This article identifies the strategic types in the hospital industry based on the hospital's use of Porter's generic strategies in their pure and hybrid forms. The article also examines differences in performance of hospitals across strategic types. Results indicate that hospitals that follow a focussed cost leadership strategy, in general, have superior performance on a variety of performance measures, while hospitals that use a combination of cost leadership and differentiation perform the poorest. Implications of findings for hospital administrators are also discussed. PMID:9358260

  7. Entanglement-fluctuation relation for bipartite pure states

    NASA Astrophysics Data System (ADS)

    Villaruel, Aura Mae B.; Paraan, Francis N. C.

    2016-08-01

    We identify subsystem fluctuations (variances) that measure entanglement in an arbitrary bipartite pure state. These fluctuations are of observables that generalize the notion of polarization to an arbitrary N -level subsystem. We express this polarization fluctuation in terms of subsystem purity and other entanglement measures. The derived entanglement-fluctuation relation is evaluated for the ground states of a one-dimensional free-fermion gas and the Affleck-Kennedy-Lieb-Tasaki spin chain. Our results provide a framework for experimentally measuring entanglement using Stern-Gerlach-type state selectors.

  8. Effect of grain sizes on mechanical properties and biodegradation behavior of pure iron for cardiovascular stent application

    PubMed Central

    Obayi, Camillus Sunday; Tolouei, Ranna; Mostavan, Afghany; Paternoster, Carlo; Turgeon, Stephane; Okorie, Boniface Adeleh; Obikwelu, Daniel Oray; Mantovani, Diego

    2016-01-01

    Abstract Pure iron has been demonstrated as a potential candidate for biodegradable metal stents due to its appropriate biocompatibility, suitable mechanical properties and uniform biodegradation behavior. The competing parameters that control the safety and the performance of BMS include proper strength-ductility combination, biocompatibility along with matching rate of corrosion with healing rate of arteries. Being a micrometre-scale biomedical device, the mentioned variables have been found to be governed by the average grain size of the bulk material. Thermo-mechanical processing techniques of the cold rolling and annealing were used to grain-refine the pure iron. Pure Fe samples were unidirectionally cold rolled and then isochronally annealed at different temperatures with the intention of inducing different ranges of grain size. The effect of thermo-mechanical treatment on mechanical properties and corrosion rates of the samples were investigated, correspondingly. Mechanical properties of pure Fe samples improved significantly with decrease in grain size while the corrosion rate decreased marginally with decrease in the average grain sizes. These findings could lead to the optimization of the properties to attain an adequate biodegradation-strength-ductility balance. PMID:25482336

  9. Efficient production of optically pure L-lactic acid from food waste at ambient temperature by regulating key enzyme activity.

    PubMed

    Li, Xiang; Chen, Yinguang; Zhao, Shu; Chen, Hong; Zheng, Xiong; Luo, Jinyang; Liu, Yanan

    2015-03-01

    Bio-production of optically pure L-lactic acid from food waste has attracted much interest as it can treat organic wastes with simultaneous recovery of valuable by-products. However, the yield of L-lactic acid was very low and no optically pure L-lactic acid was produced in the literature due to (1) the lower activity of enzymes involved in hydrolysis and L-lactic acid generation, and (2) the participation of other enzymes related to D-lactic acid and acetic and propionic acids production. In this paper, a new strategy was reported for effective production of optically pure L-lactic acid from food waste at ambient temperature, i.e. via regulating key enzyme activity by sewage sludge supplement and intermittent alkaline fermentation. It was found that not only optically pure L-lactic acid was produced, but the yield was enhanced by 2.89-fold. The mechanism study showed that the activities of enzymes relevant to food waste hydrolysis and lactic acid production were enhanced, and the key enzymes related to volatile fatty acids and D-lactic acid generations were severally decreased or inhibited. Also, the microbes responsible for L-lactic acid production were selectively proliferated. Finally, the pilot-scale continuous experiment was conducted to testify the feasibility of this new technique.

  10. Effect of grain sizes on mechanical properties and biodegradation behavior of pure iron for cardiovascular stent application.

    PubMed

    Obayi, Camillus Sunday; Tolouei, Ranna; Mostavan, Afghany; Paternoster, Carlo; Turgeon, Stephane; Okorie, Boniface Adeleh; Obikwelu, Daniel Oray; Mantovani, Diego

    2016-01-01

    Pure iron has been demonstrated as a potential candidate for biodegradable metal stents due to its appropriate biocompatibility, suitable mechanical properties and uniform biodegradation behavior. The competing parameters that control the safety and the performance of BMS include proper strength-ductility combination, biocompatibility along with matching rate of corrosion with healing rate of arteries. Being a micrometre-scale biomedical device, the mentioned variables have been found to be governed by the average grain size of the bulk material. Thermo-mechanical processing techniques of the cold rolling and annealing were used to grain-refine the pure iron. Pure Fe samples were unidirectionally cold rolled and then isochronally annealed at different temperatures with the intention of inducing different ranges of grain size. The effect of thermo-mechanical treatment on mechanical properties and corrosion rates of the samples were investigated, correspondingly. Mechanical properties of pure Fe samples improved significantly with decrease in grain size while the corrosion rate decreased marginally with decrease in the average grain sizes. These findings could lead to the optimization of the properties to attain an adequate biodegradation-strength-ductility balance.

  11. Systematic experimental study of pure shear type dielectric elastomer membranes with different electrode and film thicknesses

    NASA Astrophysics Data System (ADS)

    Hodgins, M.; Seelecke, S.

    2016-09-01

    An approach to reduce the voltage required for dielectric elastomer actuators is to reduce film thickness. However, if the electrode thickness is not similarly reduced, the electrode’s mechanical behavior can increasingly and negatively impact the overall actuator behavior. This effect is yet to be studied and quantified for pure shear type specimens; a type recommended in a recent DE standardization journal publication. Therefore, in this work, using pure shear specimens, a comparative study of membrane actuators of different film thickness (20, 50 and 100 μm) is performed. Electrodes of different thicknesses are screen printed and tested in a uniaxial test device. The stiffening effect due to the solid-state electrodes is demonstrated by performing force-elongation tests for specimens with and without electrodes. Additionally the importance of thin electrodes (relative to film thickness) was demonstrated through a number of electromechanical tests. Isotonic tests revealed a lower electro-mechanical sensitivity for the 20 μm film when compared with the 50 and 100 μm films. This was attributed to the relatively thick electrodes. Best actuation results were achieved when the total electrode thickness was at least 15x thinner than the dielectric membrane thickness.

  12. Relative toxicities of pure propylene and ethylene glycol and formulated deicers on plant species

    SciTech Connect

    DuFresne, D.L.; Pillard, D.A.

    1994-12-31

    Propylene and ethylene glycol deicers are commonly used at airports in the US and other countries to remove and retard the accumulation of snow and ice on aircraft. Deicers may not only enter water bodies without treatment, due to excessive storm-related flow, but also may expose terrestrial organisms to high concentrations through surface runoff. Most available toxicity data are for aquatic vertebrates and invertebrate species; this study examined effects on terrestrial and aquatic plants. Terrestrial plant species included both a monocot (rye grass, Lolium perenne) and a dicot (lettuce, Lactuca saliva). Aquatic species included a single cell alga (Selenastrum capricomutum), and an aquatic macrophyte (duckweed, Lemna minor). Glycol deicers were obtained in the formulated mixtures used on aircraft. Pure ethylene and propylene glycol were obtained from Sigma{reg_sign}. Parameters measured included germination, root and shoot length, survival, and growth. Formulated deicers, like those used at airports, were generally more toxic than pure chemicals, based on glycol concentration. This greater toxicity of formulated deicers is consistent with results of tests using animal species.

  13. Relation Between Stereographic Projection and Concurrence Measure in Bipartite Pure States

    NASA Astrophysics Data System (ADS)

    Najarbashi, G.; Seifi, B.

    2016-10-01

    One-qubit pure states, living on the surface of Bloch sphere, can be mapped onto the usual complex plane by using stereographic projection. In this paper, after reviewing the entanglement of two-qubit pure state, it is shown that the quaternionic stereographic projection is related to concurrence measure. This is due to the fact that every two-qubit state, in ordinary complex field, corresponds to the one-qubit state in quaternionic skew field, called quaterbit. Like the one-qubit states in complex field, the stereographic projection maps every quaterbit onto a quaternion number whose complex and quaternionic parts are related to Schmidt and concurrence terms respectively. Rather, the same relation is established for three-qubit state under octonionic stereographic projection which means that if the state is bi-separable then, quaternionic and octonionic terms vanish. Finally, we generalize recent consequences to 2⊗ N and 4⊗ N dimensional Hilbert spaces ( N ≥ 2) and show that, after stereographic projection, the quaternionic and octonionic terms are entanglement sensitive. These trends are easily confirmed by direct computation for general multi-particle W- and GHZ-states.

  14. Use of pure nickel and LiOH for thermal energy storage

    NASA Technical Reports Server (NTRS)

    Whittenberger, J. D.

    1988-01-01

    The solid to liquid phase transformation of LiOH has been proposed as an ideal candidate thermal energy storage media for a Rankine Cycle powered electrical generation unit envisioned in Space Station based solar dynamic systems. Due to the corrosive nature of molten hydroxides, long term containment of LiOH is of concern. Pure nickel is thought to be a suitably resistant material, and a program has been instituted to measure the effects of prolonged exposure of liquid and gaseous LiOH on the mechanical properties of pure nickel alloys. Results to date indicate that negligible weight and thickness changes occurred in Ni alloys exposed to LiOH for as long as 2500 hr at 775 K, and essentially no difference in 77-900 K tensile properties could be detected between LiOH exposed and vacuum annealed Ni specimens. Although there was little sign of outward damage, microstructural examination revealed that all hydroxide contaminated tensile test specimens had surface connected intergranular cracks along the gage lengths. Two other potential problems, which have strong implications with respect to a LiOH/Ni energy storage system, were also noted during the corrosion experiments. In particular stress corrosion cracking of weld joints in pressurized vessel and permeation of hydrogen through nickel were observed.

  15. A class representative model for Pure Parsimony Haplotyping under uncertain data.

    PubMed

    Catanzaro, Daniele; Labbé, Martine; Porretta, Luciano

    2011-01-01

    The Pure Parsimony Haplotyping (PPH) problem is a NP-hard combinatorial optimization problem that consists of finding the minimum number of haplotypes necessary to explain a given set of genotypes. PPH has attracted more and more attention in recent years due to its importance in analysis of many fine-scale genetic data. Its application fields range from mapping complex disease genes to inferring population histories, passing through designing drugs, functional genomics and pharmacogenetics. In this article we investigate, for the first time, a recent version of PPH called the Pure Parsimony Haplotype problem under Uncertain Data (PPH-UD). This version mainly arises when the input genotypes are not accurate, i.e., when some single nucleotide polymorphisms are missing or affected by errors. We propose an exact approach to solution of PPH-UD based on an extended version of Catanzaro et al.[1] class representative model for PPH, currently the state-of-the-art integer programming model for PPH. The model is efficient, accurate, compact, polynomial-sized, easy to implement, solvable with any solver for mixed integer programming, and usable in all those cases for which the parsimony criterion is well suited for haplotype estimation. PMID:21464966

  16. Relation Between Stereographic Projection and Concurrence Measure in Bipartite Pure States

    NASA Astrophysics Data System (ADS)

    Najarbashi, G.; Seifi, B.

    2016-06-01

    One-qubit pure states, living on the surface of Bloch sphere, can be mapped onto the usual complex plane by using stereographic projection. In this paper, after reviewing the entanglement of two-qubit pure state, it is shown that the quaternionic stereographic projection is related to concurrence measure. This is due to the fact that every two-qubit state, in ordinary complex field, corresponds to the one-qubit state in quaternionic skew field, called quaterbit. Like the one-qubit states in complex field, the stereographic projection maps every quaterbit onto a quaternion number whose complex and quaternionic parts are related to Schmidt and concurrence terms respectively. Rather, the same relation is established for three-qubit state under octonionic stereographic projection which means that if the state is bi-separable then, quaternionic and octonionic terms vanish. Finally, we generalize recent consequences to 2⊗N and 4⊗N dimensional Hilbert spaces (N ≥ 2) and show that, after stereographic projection, the quaternionic and octonionic terms are entanglement sensitive. These trends are easily confirmed by direct computation for general multi-particle W- and GHZ-states.

  17. Lasting pure-motor deficits after focal posterior internal capsule white-matter infarcts in rats

    PubMed Central

    Blasi, Francesco; Whalen, Michael J; Ayata, Cenk

    2015-01-01

    Small white-matter infarcts of the internal capsule are clinically prevalent but underrepresented among currently available animal models of ischemic stroke. In particular, the assessment of long-term outcome, a primary end point in clinical practice, has been challenging due to mild deficits and the rapid and often complete recovery in most experimental models. We, therefore, sought to develop a focal white-matter infarction model that can mimic the lasting neurologic deficits commonly observed in stroke patients. The potent vasoconstrictor endothelin-1 (n=24) or vehicle (n=9) was stereotactically injected into the internal capsule at one of three antero-posterior levels (1, 2, or 3 mm posterior to bregma) in male Sprague-Dawley rats. Endothelin-injected animals showed highly focal (~1 mm3) and reproducible ischemic infarcts, with severe axonal and myelin loss accompanied by cellular infiltration when examined 2 and 4 weeks after injection. Only those rats injected with endothelin-1 at the most posterior location developed robust and pure-motor deficits in adhesive removal, cylinder and foot-fault tests that persisted at 1 month, without detectable sensory impairments. In summary, we present an internal capsule stroke model optimized to produce lasting pure-motor deficits in rats that may be suitable to study neurologic recovery and rehabilitation after white-matter injury. PMID:25649992

  18. Electrochemical and Passive Behaviors of Pure Copper Fabricated by Accumulative Roll-Bonding (ARB) Process

    NASA Astrophysics Data System (ADS)

    Imantalab, O.; Fattah-alhosseini, A.

    2015-07-01

    In the present work, electrochemical and passive behaviors of pure copper fabricated by accumulative roll-bonding (ARB) process in 0.01 M borax solution (pH = 9.1) have been studied. Before any electrochemical measurements, evaluation of microstructure was obtained by Vickers microhardness, x-ray diffraction (XRD), and transmission electron microscopy. The results of microhardness tests revealed that microhardness values increased with the increasing number of ARB cycles. Also a sharp increase was seen in microhardness after the first ARB cycle, whereas mediocre additional increases were observed afterward up to the seven cycles. Moreover, XRD patterns showed that the mean crystallite size values decrease with the increasing number of ARB cycles. To investigate the electrochemical and passive behaviors of the samples, the potentiodynamic polarization, Mott-Schottky analysis and electrochemical impedance spectroscopy (EIS) were carried out. Polarization plots revealed that as a result of ARB, the corrosion behavior of the specimens improves compared with the annealed pure copper. Also, the Mott-Schottky analysis and EIS measurements showed that the increasing number of ARB cycles offer better conditions for forming the passive films with higher protection behavior, due to the growth of less-defective films.

  19. Reactive uptake of NO3 on pure water and ionic solutions

    NASA Astrophysics Data System (ADS)

    Rudich, Yinon; Talukdar, Ranajit K.; Ravishankara, A. R.; Fox, R. W.

    1996-09-01

    The reactive uptake coefficients (γ) of NO3 onto pure water and dilute solutions of NaCl, NaBr, and NaNO2 were measured using a wetted-wall flow-tube setup combined with a long-path absorption cell for the detection of NO3. The measured γ values were in the range 1.5 × 10-4 - 6 × 10-3, depending on the salt concentration in the water. By measuring γ as a function of salt concentration, HD�򉾊.5 for NO3 in water was determined to be (1.9 ± 0.4) × 10-3 M atm-1 cm s-0.5 at 273 K, assuming that the rate coefficient for the reaction of NO3 with Cl- is 2.76 × 106 M-1 s-1 at 273 K. The Henry's law coefficient for NO3 in water is estimated to be 0.6 ± 0.3 M atm-1, assuming that the diffusion coefficient of NO3 in water is D�� = (1.0 ± 0.5) × 10-5 cm2 s-1. Uptake of NO3 on pure water is interpreted as due to reaction of NO3(aq) with H2O(��) to produce HNO3 and OH in the liquid phase. Implications of these findings to the chemistry of NO3 in the troposphere are also discussed.

  20. Bounds on probability of transformations between multipartite pure states

    SciTech Connect

    Cui Wei; Helwig, Wolfram; Lo, Hoi-Kwong

    2010-01-15

    For a tripartite pure state of three qubits, it is well known that there are two inequivalent classes of genuine tripartite entanglement, namely the Greenberger-Horne-Zeilinger (GHZ) class and the W class. Any two states within the same class can be transformed into each other with stochastic local operations and classical communication with a nonzero probability. The optimal conversion probability, however, is only known for special cases. Here, lower and upper bounds are derived for the optimal probability of transformation from a GHZ state to other states of the GHZ class. A key idea in the derivation of the upper bounds is to consider the action of the local operations and classical communications (LOCC) protocol on a different input state, namely 1/sq root(2)[|000>-|111>], and to demand that the probability of an outcome remains bounded by 1. We also find an upper bound for more general cases by using the constraints of the so-called interference term and 3-tangle. Moreover, some of the results are generalized to the case in which each party holds a higher dimensional system. In particular, the GHZ state generalized to three qutrits; that is, |GHZ{sub 3}>=1/sq root(3)[|000>+|111>+|222>] shared among three parties can be transformed to any tripartite three-qubit pure state with probability 1 via LOCC. Some of our results can also be generalized to the case of a multipartite state shared by more than three parties.

  1. Pure menstrual migraine with sensory aura: a case report.

    PubMed

    Chen, Jiann-Jy; Hsu, Yung-Chu; Chen, Dem-Lion

    2012-07-01

    Hormonal changes related to the menstrual cycle have a great impact on migraines in women. Menstrual migraine attacks are almost invariably without aura. Categorizing migraines into menstrual or non-menstrual types is one way to stratify migraines without aura according to the appendix criteria of the International Classification of Headache Disorders. We report a peri-menopausal woman whose sensory aura exclusively heralded menstrual migraine. A 51-year-old woman had suffered from monthly episodic headaches since the age of 46. Before a headache, and within 1 h on the first day of her menstruation, she always experienced numbness in her entire left upper limb. After the sensory aura, migrainous headaches occurred with nausea and photophobia. In the postmenopausal period, she no longer had sensory aura, and her headache pattern changed and became less severe. Her physical and neurologic exams as well as electroencephalography, brain magnetic resonance imaging, and conventional angiography were all normal. She fulfilled the diagnosis of pure menstrual migraine with typical sensory aura. To our knowledge, this is the first formal case report of pure menstrual migraine with aura.

  2. Visual command hallucinations in a patient with pure alexia

    PubMed Central

    ffytche, D; Lappin, J; Philpot, M

    2004-01-01

    Around 25% of patients with visual hallucinations secondary to eye disease report hallucinations of text. The hallucinated text conveys little if any meaning, typically consisting of individual letters, words, or nonsense letter strings (orthographic hallucinations). A patient is described with textual visual hallucinations of a very different linguistic content following bilateral occipito-temporal infarcts. The hallucinations consisted of grammatically correct, meaningful written sentences or phrases, often in the second person and with a threatening and command-like nature (syntacto-semantic visual hallucinations). A detailed phenomenological interview and visual psychophysical testing were undertaken. The patient showed a classical ventral occipito-temporal syndrome with achromatopsia, prosopagnosia, and associative visual agnosia. Of particular significance was the presence of pure alexia. Illusions of colour induced by monochromatic gratings and a novel motion–direction illusion were also observed, both consistent with the residual capacities of the patient's spared visual cortex. The content of orthographic visual hallucinations matches the known specialisations of an area in the left posterior fusiform gyrus—the visual word form area (VWFA)—suggesting the two are related. The VWFA is unlikely to be responsible for the syntacto-semantic hallucinations described here as the patient had a pure alexic syndrome, a known consequence of VWFA lesions. Syntacto-semantic visual hallucinations may represent a separate category of textual hallucinations related to the cortical network implicated in the auditory hallucinations of schizophrenia. PMID:14707313

  3. Laser ignition of bulk 1018 carbon steel in pure oxygen

    NASA Technical Reports Server (NTRS)

    Nguyen, K.; Branch, M. C.

    1986-01-01

    Experiments were undertaken to study the ignition characteristics of bulk 1018 carbon steel in a pure oxygen environment. Cylindrical 1018 carbon steel specimens 5 mm in diameter and 5 mm high were ignited by a focused CW CO2 laser beam in a cool, static, pure oxygen environment at oxygen pressures ranging from 0.103 to 6.895 MPa. A two-color pyrometer was designed and used to measure the ignition temperatures of the specimens. The temperature history of a spot approximately 0.5 mm in diameter located at the center of the specimen top surface was recorded with a maximum time resolution of 25 microsec, and with an accuracy of a few percent. Ignition temperature of bulk 1018 carbon steel was identified from the temperature history curve with the aid of the light intensity curve. Results show that 1018 carbon steel specimens ignite at temperatures between 1388 and 1450 K, which are below the melting range of the alloy (1662-1685 K). The ignition temperature of 1018 carbon steel is mildly dependent on oxygen pressure over the range of oxygen pressure investigated in this study.

  4. Thallium Transfer from Hydrochloric Acid Media into Pure Ionic Liquids.

    PubMed

    Tereshatov, Evgeny E; Boltoeva, Maria Yu; Mazan, Valerie; Volia, Merinda F; Folden, Charles M

    2016-03-10

    Pure hydrophobic ionic liquids are known to extract metallic species from aqueous solutions. In this work we have systematically investigated thallium (Tl) extraction from aqueous hydrochloric acid (HCl) solutions into six pure fluorinated ionic liquids, namely imidazolium- and pyrrolidinium-based ionic liquids with bis(trifluoromethanesulfonyl)imide and bis(fluorosulfonyl)-imide anions. The dependence of the Tl extraction efficiency on the structure and composition of the ionic liquid ions, metal oxidation state, and initial metal and aqueous acid concentrations have been studied. Tl concentrations were on the order of picomolar (analyzed using radioactive tracers) and millimolar (analyzed using inductively coupled plasma mass spectrometry). The extraction of the cationic thallium species Tl(+) is higher for ionic liquids with more hydrophilic cations, while for the TlX(z)(3-z) anionic species (where X = Cl(-) and/or Br(-)), the extraction efficiency is greater for ionic liquids with more hydrophobic cations. The highest distribution value of Tl(III) was approximately 2000. An improved mathematical model based on ion exchange and ion pair formation mechanisms has been developed to describe the coextraction of two different anionic species, and the relative contributions of each mechanism have been determined. PMID:26769597

  5. Pure chromosome-specific PCR libraries from single sorted chromosomes.

    PubMed Central

    VanDevanter, D R; Choongkittaworn, N M; Dyer, K A; Aten, J; Otto, P; Behler, C; Bryant, E M; Rabinovitch, P S

    1994-01-01

    Chromosome-specific DNA libraries can be very useful in molecular and cytogenetic genome mapping studies. We have developed a rapid and simple method for the generation of chromosome-specific DNA sequences that relies on polymerase chain reaction (PCR) amplification of a single flow-sorted chromosome or chromosome fragment. Previously reported methods for the development of chromosome libraries require larger numbers of chromosomes, with preparation of pure chromosomes sorted by flow cytometry, generation of somatic cell hybrids containing targeted chromosomes, or a combination of both procedures. These procedures are labor intensive, especially when hybrid cell lines are not already available, and this has limited the generation of chromosome-specific DNA libraries from nonhuman species. In contrast, a single sorted chromosome is a pure source of DNA for library production even when flow cytometric resolution of chromosome populations is poor. Furthermore, any sorting cytometer may be used with this technique. Using this approach, we demonstrate the generation of PCR libraries suitable for both molecular and fluorescence in situ hybridization studies from individual baboon and canine chromosomes, separate human homologues, and a rearranged marker chromosome from a transformed cell line. PCR libraries specific to subchromosomal regions have also been produced by sorting a small chromosome fragment. This simple and rapid technique will allow generation of nonhuman linkage maps and probes for fluorescence in situ hybridization and the characterization of marker chromosomes from solid tumors. In addition, allele-specific libraries generated by this strategy may also be useful for mapping genetic diseases. Images PMID:8016078

  6. Visual command hallucinations in a patient with pure alexia.

    PubMed

    Ffytche, D H; Lappin, J M; Philpot, M

    2004-01-01

    Around 25% of patients with visual hallucinations secondary to eye disease report hallucinations of text. The hallucinated text conveys little if any meaning, typically consisting of individual letters, words, or nonsense letter strings (orthographic hallucinations). A patient is described with textual visual hallucinations of a very different linguistic content following bilateral occipito-temporal infarcts. The hallucinations consisted of grammatically correct, meaningful written sentences or phrases, often in the second person and with a threatening and command-like nature (syntacto-semantic visual hallucinations). A detailed phenomenological interview and visual psychophysical testing were undertaken. The patient showed a classical ventral occipito-temporal syndrome with achromatopsia, prosopagnosia, and associative visual agnosia. Of particular significance was the presence of pure alexia. Illusions of colour induced by monochromatic gratings and a novel motion-direction illusion were also observed, both consistent with the residual capacities of the patient's spared visual cortex. The content of orthographic visual hallucinations matches the known specialisations of an area in the left posterior fusiform gyrus--the visual word form area (VWFA)--suggesting the two are related. The VWFA is unlikely to be responsible for the syntacto-semantic hallucinations described here as the patient had a pure alexic syndrome, a known consequence of VWFA lesions. Syntacto-semantic visual hallucinations may represent a separate category of textual hallucinations related to the cortical network implicated in the auditory hallucinations of schizophrenia.

  7. Pure rotation of a prism on a ramp

    PubMed Central

    Zhao, Zhen; Liu, Caishan; Ma, Daolin

    2014-01-01

    In this work, we study a prism with a cross section in polygon rolling on a ramp inclined at a small angle. The prism under gravity rolls purely around each individual edge, intermittently interrupted by a sequence of face collisions between the side face of the prism and the ramp. By limiting the prism in a planar motion, we propose a mathematical model to deal with the events of the impacts. With a pair of laser-Doppler vibrometers, experiments are also conducted to measure the motions of various prisms made of different materials and with different edge number. Not only are good agreements achieved between our numerical and experimental results, but also an intriguing physical phenomenon is discovered: the purely rolling motion is nearly independent of the prism's materials, yet it is closely related to the prism's geometry. Imagine that an ideal circular section can be approximately equivalent to a polygon with a large enough edge number N, the finding presented in this paper may help discover the physical mechanism of rolling friction. PMID:25197242

  8. A purely flexible lightweight membrane-type acoustic metamaterial

    NASA Astrophysics Data System (ADS)

    Ma, Fuyin; Wu, Jiu Hui; Huang, Meng; Zhang, Weiquan; Zhang, Siwen

    2015-05-01

    This paper proposes a purely flexible lightweight membrane-type acoustic structure, wherein one kind of flexible lightweight rubber material takes the roles of mass and stiffness and another type of lightweight flexible EVA (ethylene-vinyl acetate copolymer) or plastic material functions as the localized stiffness for each unit. Because both the scatterers and base are constituted by the same material, this type of structure breaks the limitation that the metamaterials and phononic crystals need different materials with relatively large density and elasticity modulus ratios to play the roles of the scatterers and base respectively. Based on the band structures with different units, mass block shapes and size parameters, it is suggested that the shapes of the mass block can significantly affect the band structure. In addition, this type of structure could not only open a full band gap in the low-frequency range below 500 Hz, but also obtain an ultra-low-frequency bending wave band gap in the range below 100 Hz. Finally, we take into account the semi-infinite medium as a component, and calculate the sound transmission loss (STL) to evaluate the interaction between the structure and air. An experimental validation employing the cylindrical mass structure was developed to directly support the simulation results. Since the structures proposed in this study have achieved a purely flexible lightweight design, there exists an important promotion effect to realize the engineering applications of the acoustic metamaterials in practice.

  9. Pure Ultrasonic Communication in an Endemic Bornean Frog

    PubMed Central

    Arch, Victoria S.; Grafe, T. Ulmar; Gridi-Papp, Marcos; Narins, Peter M.

    2009-01-01

    Huia cavitympanum, an endemic Bornean frog, is the first amphibian species known to emit exclusively ultrasonic (i.e., >20 kHz) vocal signals. To test the hypothesis that these frogs use purely ultrasonic vocalizations for intraspecific communication, we performed playback experiments with male frogs in their natural calling sites. We found that the frogs respond with increased calling to broadcasts of conspecific calls containing only ultrasound. The field study was complemented by electrophysiological recordings from the auditory midbrain and by laser Doppler vibrometer measurements of the tympanic membrane's response to acoustic stimulation. These measurements revealed that the frog's auditory system is broadly tuned over high frequencies, with peak sensitivity occurring within the ultrasonic frequency range. Our results demonstrate that H. cavitympanum is the first non-mammalian vertebrate described to communicate with purely ultrasonic acoustic signals. These data suggest that further examination of the similarities and differences in the high-frequency/ultrasonic communication systems of H. cavitympanum and Odorrana tormota, an unrelated frog species that produces and detects ultrasound but does not emit exclusively ultrasonic calls, will afford new insights into the mechanisms underlying vertebrate high-frequency communication. PMID:19401782

  10. Direct measurement of pure absorbance spectra of living phototrophic microorganisms.

    PubMed

    Göbel, F

    1978-02-01

    The pure absorbance of turbid cell suspensions of various phototrophic microorganisms were determined by collecting the scattered light. A conventional spectrophotometer was used, equipped with an intergrating sphere as receiver unit, which allowed precise measurements of the absorbance in the range from zero to 0.1. In the wavelength range 300--1100 nm, where photosynthesis occurs, light scattered only once by a bacterial cell retains predominantly the forward direction. This allows measurements of pure absorption, when the concentration of cells which the light has to pass through is small. For example, by comparison of measurements of pigmented and nonpigmented cell suspensions of Rhodopseudomonas acidophila, it was shown that the total sum of scattered light can be collected. The best results were obtained using cuvettes with a light path of 0.1 cm or 0.2 cm to measure cell suspensions of about 0.2 mg dry weight per ml. For R. acidophila this corresponds to 1--3 cell layers. Extinction-, absorbance- and scattering spectra for R. acidophila are presented, in addition to the absorbance spectra for Rhodospirillum rubrum, Aphanocapsa and Scenedesmus.

  11. The Passive Film Characteristics of Cold Deformed Pure Copper

    NASA Astrophysics Data System (ADS)

    Fattah-Alhosseini, Arash; Naseri, Majid; Imantalab, Omid; Gholami, Davood; Haghshenas, Meysam

    2016-09-01

    In the present study, the effect of cold deformation on the electrochemical and passive behaviors of pure copper in 0.01 M NaOH solution was investigated. The dislocation density in cold deformation was calculated using a recently developed JAVA-based software, materials analysis using diffraction, based on Rietveld's whole x-ray pattern fitting methodology. At the thickness reduction of 70%, the microhardness measured as 125.30 HV, which is 1.56 times than that in the annealed pure copper (80.25 HV). Potentiodynamic polarization plots and electrochemical impedance spectroscopy measurements showed that increasing the cold deformation offers better conditions for forming the passive films. In the Mott-Schottky analysis, no evidence for n-type behavior was obtained which indicates that the oxygen vacancies and the copper interstitials did not have any significant population density in the passive films. Also, this analysis revealed that with increasing cold deformation, the acceptor density of the passive films decreased.

  12. Directional Solidification of Pure Succinonitrile and a Succinonitrile-Acetone Alloy

    NASA Technical Reports Server (NTRS)

    Simpson, James E.; deGroh, Henry C., III; Garimella, Suresh V.

    1999-01-01

    An experimental study of the horizontal Bridgman growth of pure succinonitrile (SCN) and of a succinonitrile-1.0 mol.% acetone alloy (SCN-1.0 mol.% ACE) has been performed. Experiments involving both a stationary thermal field (no-growth case) and a translating thermal field (growth case) were conducted. Growth rates of 2 and 40 micrometers/s were investigated. For the pure SCN experiments, the velocity field in the melt was estimated using video images of seed particles in the melt. Observations of the seed particles indicate that a primary longitudinal convective cell is formed. The maximum velocity of two different particles which traveled along similar paths was the same and equal to 1.49 +/- 0.01 mm/s. The general accuracy of velocity measurements is estimated to be +/- 0.08 mm/s, though the data shows consistency to within +/- 0.02 mm/s. The shape of the solid/liquid interface was also quantitatively determined. The solid/liquid interface was stable (non-dendritic and non-cellular) but not flat; rather it was significantly distorted by the influence of convection in (he melt and, for the growth case, by the moving temperature boundary conditions along the ampoule. It was found that the interface shape and position were highly dependent on the alignment of the ampoule in the apparatus. Consequently, the ampoule was carefully aligned for all experiments. The values for front location agree with those determined in previous experiments. For the alloy experiments, the solid/liquid interface was determined to be unstable at growth rates greater than 2.8 micrometers/s, but stable for the cases of no-growth and growth at 2 micrometers/s. When compared to the shape of the pure SCN interface, the alloy interface forms closer to the cold zone, indicating that the melting temperature decreased due to the alloying element. Extensive temperature measurements were performed on the outside of the ampoule containing pure SCN. The resulting thermal profiles are presented in

  13. Directional Solidification of Pure Succinonitrile and a Succinonitrile-Acetone Alloy

    NASA Technical Reports Server (NTRS)

    Simpson, James E.; deGroh, Henry C., III; Garimella, Suresh V.

    2000-01-01

    An experimental study of the horizontal Bridgman growth of pure succinonitrile (SCN) and of a succinonitrile-1.0 mol% acetone alloy (SCN-1.0 mol.% ACE) has been performed. Experiments involving both a stationary thermal field (no-growth case) and a translating thermal field (growth case) were conducted. Growth rates of 2 and 40 micrometers/sec were investigated. For the pure SCN experiments, the velocity field in the melt was estimated using video images of seed particles in the melt. Observations of the seed particles indicate that a primary longitudinal convective cell is formed. The maximum velocity of two different particles which traveled along similar paths was the same and equal to 1.49 +/- 0.01 mm/s. The general accuracy of velocity measurements is estimated to be +/-0.08 mm/s, though the data shows consistency to within +/- 0.02 mm/s. The shape of the solid/liquid interface was also quantitatively determined. The solid/liquid interface was stable (non-dendritic and non-cellular) but not flat: rather it was significantly distorted by the influence of connection in the melt and, for the growth case, by the moving temperature boundary conditions along the ampoule. It was found that the interface shape and position were highly dependent on the alignment of the ampoule in the apparatus. Consequently, the ampoule was carefully aligned for all experiments. The values for front location agree with those determined in previous experiments. For the alloy experiments, the solid/liquid interface was determined to be unstable at growth rates greater than 2.8 micrometers/sec, but stable for the cases of no-growth and growth at 2 micrometers/sec. When compared to the shape of the pure SCN interface, the alloy interface forms closer to the cold zone, indicating that the melting temperature decreased due to the alloying element. Extensive temperature measurements were performed on the outside of the ampoule containing pure SCN. The resulting thermal profiles are presented

  14. Expected net present value of pure and mixed sexed semen artificial insemination strategies in dairy heifers.

    PubMed

    Olynk, N J; Wolf, C A

    2007-05-01

    Sexed semen has been a long-anticipated tool for dairy farmers to obtain more heifer calves, but challenges exist for integrating sexed semen into commercial dairy farm reproduction programs. The decreased conception rates (CR) experienced with sexed semen make virgin heifers better suited for insemination with sexed semen than lactating dairy cows. This research sought to identify when various sexed semen breeding strategies provided higher expected net present value (NPV) than conventional artificial insemination (AI) breeding schemes, indicating which breeding scheme is advisable under various scenarios. Budgets were developed to calculate the expected NPV of various AI breeding strategies incorporating conventional (non-sexed) and sexed semen. In the base budgets, heifer and bull calf values were held constant at $500 and $110, respectively. The percentage of heifers expected to be born after breeding with conventional and sexed semen used was 49.2 and 90%, respectively. Breeding costs per AI were held constant at $15.00 per AI for conventional semen and $45.00 per AI for sexed semen of approximately the same genetic value. Conventional semen CR of 58 and 65% were used, and an AI submission rate was set at 100%. Breeding strategies with sexed semen were assessed for breakeven heifer calf values and sexed semen costs to obtain a NPV equal to that achieved with conventional semen. Breakeven heifer calf values for pure sexed semen strategies with a constant 58 and 65% base CR in which sexed semen achieved 53% of the base CR are $732.11 and $664.26, respectively. Breakeven sexed semen costs per AI of $17.16 and $22.39, compared with $45.00 per AI, were obtained to obtain a NPV equal to that obtained with pure conventional semen for base CR of 58 and 65%, respectively. The strategy employing purely sexed semen, with base CR of both 58 and 65%, yielded a lower NPV than purely conventional semen in all but the best-case scenario in which sexed semen provides 90% of

  15. 77 FR 66911 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel PURE INSANITY; Invitation for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel PURE INSANITY... of the vessel PURE INSANITY is: Intended Commercial Use of Vessel: ``Vessel Chartering''...

  16. ℬ(H) has a pure state that is not multiplicative on any masa

    PubMed Central

    Akemann, Charles; Weaver, Nik

    2008-01-01

    Assuming the continuum hypothesis, we prove that ℬ(H) has a pure state whose restriction to any masa is not pure. This resolves negatively old conjectures of Kadison and Singer and of Anderson. PMID:18378909

  17. Non-axisymmetric magnetic modes of neutron stars with purely poloidal magnetic fields

    NASA Astrophysics Data System (ADS)

    Asai, Hidetaka; Lee, Umin; Yoshida, Shijun

    2016-01-01

    We calculate non-axisymmetric oscillations of neutron stars magnetized by purely poloidal magnetic fields. We use polytropes of index n = 1 and 1.5 as a background model, where we ignore the equilibrium deformation due to the magnetic field. Since separation of variables is not possible for the oscillation of magnetized stars, we employ finite series expansions for the perturbations using spherical harmonic functions. Solving the oscillation equations as the boundary and eigenvalue problem, we find two kinds of discrete magnetic modes, that is, stable (oscillatory) magnetic modes and unstable (monotonically growing) magnetic modes. For isentropic models, the frequency or the growth rate of the magnetic modes is exactly proportional to BS, the strength of the field at the surface. The oscillation frequency and the growth rate are affected by the buoyant force in the interior, and the stable stratification tends to stabilize the unstable magnetic modes.

  18. First-principles studies on pure and doped C32 clusters

    NASA Astrophysics Data System (ADS)

    Sun, Q.; Wang, Q.; Yu, J. Z.; Ohno, K.; Kawazoe, Y.

    2001-03-01

    On the basis of first-principles calculations, pure and doped C32 clusters are studied. Among the nine structural isomers, the fullerene structure with D3 symmetry is found to be the most stable. Due to the small size of the C32 cage, Li and Na atoms can be stably encapsulated, while K and Be atoms are not. On encapsulation, the bond length of the H2 molecule is reduced while the vibration frequency is increased. Substitutional doping is more favourable than endohedral doping for Si atoms. Because of the sp2-bonding features of C atoms, the Si atom is also threefold coordinated in substitutional doping; however, the existence of one dangling bond in the Si atom makes this doped heterofullerene reactive at the Si site, and H termination can produce substantial energy gain.

  19. Tension-compression-tension tertiary twins in coarse-grained polycrystalline pure magnesium at room temperature

    DOE PAGESBeta

    Yu, Qin; Jiang, Yanyao; Wang, Jian

    2015-04-07

    Using electron backscatter diffraction, the microstructural features of tension–compression–tension (T–C–T) tertiary twins are studied in coarse-grained pure polycrystalline magnesium subjected to monotonic compression along the extrusion direction in ambient air. T–C–T tertiary twins are developed due to the formation of a compression–tension double twin inside a primary tension twin. All the observed T–C–T twin variants are of TiCjTj type. TiCi+1Ti+1 (or TiCi–1Ti–1) variants are observed more frequently than TiCi+2Ti+2 (or TiCi–2Ti–2) variants. Moreover, the number of tertiary twin lamellae increases with the applied compressive strain.

  20. Observations of the J = 10 manifold of the pure rotational band of phosphine on Saturn

    NASA Technical Reports Server (NTRS)

    Haas, M. R.; Erickson, E. F.; Goorvitch, D.; Mckibbin, D. D.; Rank, D. M.

    1986-01-01

    Saturn was observed in the vicinity of the J = 10 manifold of the pure rotational band of phosphine on 1984 July 10 and 12 from NASA's Kuiper Airborne Observatory with the facility far-infrared cooled grating spectrometer. On each night observations of the full disk plus rings were made at 4 to 6 discrete wavelengths which selectively sampled the manifold and the adjacent continuum. The previously reported detection of this manifold is confirmed. After subtraction of the flux due to the rings, the data are compared with disk-averaged models of Saturn. It is found that PH3 must be strongly depleted above the thermal inversion (approx. 70 mbar). The best fitting models consistent with other observational constaints indicate that PH3 is significantly depleted at even deeper atmospheric levels ( or = 500 mbar), implying an eddy diffusion coefficient for Saturn of 10 to the 4 cm sq/sec.

  1. Conversion of pure spin current to charge current in amorphous bismuth

    SciTech Connect

    Emoto, H.; Ando, Y.; Shinjo, T.; Shiraishi, M.; Shikoh, E.; Fuseya, Y.

    2014-05-07

    Spin Hall angle and spin diffusion length in amorphous bismuth (Bi) are investigated by using conversion of a pure spin current to a charge current in a spin pumping technique. In Bi/Ni{sub 80}Fe{sub 20}/Si(100) sample, a clear direct current (DC) electromotive force due to the inverse spin Hall effect of the Bi layer is observed at room temperature under a ferromagnetic resonance condition of the Ni{sub 80}Fe{sub 20} layer. From the Bi thickness dependence of the DC electromotive force, the spin Hall angle and the spin diffusion length of the amorphous Bi film are estimated to be 0.02 and 8 nm, respectively.

  2. Pure spin-Hall magnetoresistance in Rh/Y3Fe5O12 hybrid.

    PubMed

    Shang, T; Zhan, Q F; Ma, L; Yang, H L; Zuo, Z H; Xie, Y L; Li, H H; Liu, L P; Wang, B M; Wu, Y H; Zhang, S; Li, Run-Wei

    2015-01-01

    We report an investigation of anisotropic magnetoresistance (AMR) and anomalous Hall resistance (AHR) of Rh and Pt thin films sputtered on epitaxial Y(3)Fe(5)O(12) (YIG) ferromagnetic insulator films. For the Pt/YIG hybrid, large spin-Hall magne toresistance (SMR) along with a sizable conventional anisotropic magnetoresistance (CAMR) and a nontrivial temperature dependence of AHR were observed in the temperature range of 5-300 K. In contrast, a reduced SMR with negligible CAMR and AHR was found in Rh/YIG hybrid. Since CAMR and AHR are characteristics for all ferromagnetic metals, our results suggest that the Pt is likely magnetized by YIG due to the magnetic proximity effect (MPE) while Rh remains free of MPE. Thus the Rh/YIG hybrid could be an ideal model system to explore physics and devices associated with pure spin current. PMID:26639108

  3. Pure spin-Hall magnetoresistance in Rh/Y3Fe5O12 hybrid

    NASA Astrophysics Data System (ADS)

    Shang, T.; Zhan, Q. F.; Ma, L.; Yang, H. L.; Zuo, Z. H.; Xie, Y. L.; Li, H. H.; Liu, L. P.; Wang, B. M.; Wu, Y. H.; Zhang, S.; Li, Run-Wei

    2015-12-01

    We report an investigation of anisotropic magnetoresistance (AMR) and anomalous Hall resistance (AHR) of Rh and Pt thin films sputtered on epitaxial Y3Fe5O12 (YIG) ferromagnetic insulator films. For the Pt/YIG hybrid, large spin-Hall magne toresistance (SMR) along with a sizable conventional anisotropic magnetoresistance (CAMR) and a nontrivial temperature dependence of AHR were observed in the temperature range of 5-300 K. In contrast, a reduced SMR with negligible CAMR and AHR was found in Rh/YIG hybrid. Since CAMR and AHR are characteristics for all ferromagnetic metals, our results suggest that the Pt is likely magnetized by YIG due to the magnetic proximity effect (MPE) while Rh remains free of MPE. Thus the Rh/YIG hybrid could be an ideal model system to explore physics and devices associated with pure spin current.

  4. Study of the structure and mechanical properties of pure and doped polyaniline

    NASA Astrophysics Data System (ADS)

    Shaktawat, Vinodini; Saxena, N. S.; Sharma, Kananbala

    2011-03-01

    Polyaniline (PANI) doped with different protonic acids was chemically synthesized using ammonium persulfate as an oxidant. These samples were characterized through scanning electron microscopy-energy-dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy, which confirms the acid doping. Variation of complex elastic modulus and mechanical loss factor (tan δ) has been studied with temperature of pellet of conducting PANI. It has been observed that complex modulus decreases with temperature due to thermal expansion of films. On the other hand, tan δ increases up to characteristic temperature, beyond which it shows a decreasing trend towards melting. The phase transition temperature of pure PANI is 106.1°C and is shifted to higher temperatures i.e. 137.1°C, 134°C, 138.8°C, 118.3°C, and 109.7°C with doping of PANI by protonic acids.

  5. Pure-Pursuit Reactive Path Tracking for Nonholonomic Mobile Robots with a 2D Laser Scanner

    NASA Astrophysics Data System (ADS)

    Morales, Jesús; Martínez, Jorge L.; Martínez, María A.; Mandow, Anthony

    2009-12-01

    Due to its simplicity and efficiency, the pure-pursuit path tracking method has been widely employed for planned navigation of nonholonomic ground vehicles. In this paper, we investigate the application of this technique for reactive tracking of paths that are implicitly defined by perceived environmental features. Goal points are obtained through an efficient interpretation of range data from an onboard 2D laser scanner to follow persons, corridors, and walls. Moreover, this formulation allows that a robotic mission can be composed of a combination of different types of path segments. These techniques have been successfully tested in the tracked mobile robot Auriga-[InlineEquation not available: see fulltext.] in an indoor environment.

  6. Pure spin-Hall magnetoresistance in Rh/Y3Fe5O12 hybrid

    PubMed Central

    Shang, T.; Zhan, Q. F.; Ma, L.; Yang, H. L.; Zuo, Z. H.; Xie, Y. L.; Li, H. H.; Liu, L. P.; Wang, B. M.; Wu, Y. H.; Zhang, S.; Li, Run-Wei

    2015-01-01

    We report an investigation of anisotropic magnetoresistance (AMR) and anomalous Hall resistance (AHR) of Rh and Pt thin films sputtered on epitaxial Y3Fe5O12 (YIG) ferromagnetic insulator films. For the Pt/YIG hybrid, large spin-Hall magne toresistance (SMR) along with a sizable conventional anisotropic magnetoresistance (CAMR) and a nontrivial temperature dependence of AHR were observed in the temperature range of 5–300 K. In contrast, a reduced SMR with negligible CAMR and AHR was found in Rh/YIG hybrid. Since CAMR and AHR are characteristics for all ferromagnetic metals, our results suggest that the Pt is likely magnetized by YIG due to the magnetic proximity effect (MPE) while Rh remains free of MPE. Thus the Rh/YIG hybrid could be an ideal model system to explore physics and devices associated with pure spin current. PMID:26639108

  7. On-chip low loss heralded source of pure single photons.

    PubMed

    Spring, Justin B; Salter, Patrick S; Metcalf, Benjamin J; Humphreys, Peter C; Moore, Merritt; Thomas-Peter, Nicholas; Barbieri, Marco; Jin, Xian-Min; Langford, Nathan K; Kolthammer, W Steven; Booth, Martin J; Walmsley, Ian A

    2013-06-01

    A key obstacle to the experimental realization of many photonic quantum-enhanced technologies is the lack of low-loss sources of single photons in pure quantum states. We demonstrate a promising solution: generation of heralded single photons in a silica photonic chip by spontaneous four-wave mixing. A heralding efficiency of 40%, corresponding to a preparation efficiency of 80% accounting for detector performance, is achieved due to efficient coupling of the low-loss source to optical fibers. A single photon purity of 0.86 is measured from the source number statistics without narrow spectral filtering, and confirmed by direct measurement of the joint spectral intensity. We calculate that similar high-heralded-purity output can be obtained from visible to telecom spectral regions using this approach. On-chip silica sources can have immediate application in a wide range of single-photon quantum optics applications which employ silica photonics.

  8. Age-related declines in distortion product otoacoustic emissions utilizing pure tone contralateral stimulation in CBA/CaJ mice.

    PubMed

    Varghese, George I; Zhu, Xiaoxia; Frisina, Robert D

    2005-11-01

    One role of the medial olivocochlear (MOC) auditory efferent system is to suppress cochlear outer hair cell (OHC) responses when presented with a contralateral sound. Using distortion product otoacoustic emissions (DPOAEs), the effects of active changes in OHC responses due to the MOC as a function of age can be observed when contralateral stimulation with a pure tone is applied. Previous studies have shown that there are age-related declines of the MOC when broad band noise is presented to the contralateral ear. In this study, we measured age-related changes in CBA/CaJ mice by comparing DPOAE generation with and without a contralateral pure tone at three different frequencies (12, 22, and 37 kHz). Young (n = 16), middle (n = 10) and old-aged (n = 10) CBA mice were tested. DPOAE-grams were obtained using L1 = 65 and L2 = 50 dB SPL, F1/F2 = 1.25, using eight points per octave covering a frequency range from 5.6-44.8 kHz. The pure tone was presented contralaterally at 55 dB SPL. DPOAE-grams and ABR levels indicated age-related hearing loss in the old mice. In addition, there was an overall change in DPOAEs in the middle-aged and old groups relative to the young. Pure tone stimulation was not as effective as a suppressor compared to broadband noise. An increase in pure tone frequency from 12 to 22 kHz induced greater suppression of DPOAEs, but the 37 kHz was least effective. These results indicate that as the mouse ages, there are significant changes in the efficiency of the suppression mechanism as elicited by contralateral narrowband stimuli. These findings reinforce the idea that age-related changes in the MOC or the operating points of OHCs play a role in the progression of presbycusis - age-related hearing loss in mammals.

  9. Chirally Pure Prodrugs and Their Converting Enzymes Lead to High Supersaturation and Rapid Transcellular Permeation of Benzodiazepines.

    PubMed

    Kapoor, Mamta; Cheryala, Narsihmulu; Rautiola, Davin; Georg, Gunda I; Cloyd, James C; Siegel, Ronald A

    2016-08-01

    Water-soluble prodrugs can be rapidly converted by enzymes to hydrophobic drugs, whose aqueous thermodynamic solubilities are low, but are maintained in aqueous solution at supersaturated concentrations due to slow precipitation kinetics. Recently, we investigated avizafone (AVF) in combination with Aspergillus oryzae protease as a prodrug/enzyme system intended to produce supersaturated diazepam (DZP). Several fold enhancement of permeation of supersaturated DZP across Madin-Darby canine kidney II-wild type (MDCKII-wt) monolayers was observed, compared to saturated DZP solutions. However, prodrug conversion was incomplete, putatively due to partial racemization of AVF and stereoselectivity of A oryzae protease. Here we report synthesis of chirally pure AVF, and demonstrate complete conversion to supersaturated DZP followed by complete DZP permeation at enhanced rates across MDCKII-wt cell monolayers. We also synthesized, for the first time, a chirally pure prodrug of midazolam (MDZ-pro) and carried out the same sequence of studies. A oryzae protease was identified as a benign and efficient activating enzyme for MDZ-pro. The MDZ-pro/A oryzae protease system showed greater than 25-fold increase in absorption rate of MDZ across MDCKII-wt monolayers, compared to saturated MDZ. Such chirally pure prodrug/enzyme systems are promising candidates for efficient intranasal delivery of benzodiazepine drugs used in the treatment of seizure emergencies.

  10. Equation of state for pure fluids at critical temperature

    NASA Astrophysics Data System (ADS)

    B. Khasare, S.

    2012-04-01

    In this paper, we employ the concept of probability for creating a cavity with diameter d in fluid along with the perturbation and variation approach, and develop an equation of state (EOS) for a hard sphere (HS) and Lennard—Jones (LJ) fluids. A suitable axiomatic form for surface tension S(r) is assumed for the pure fluid, with r as a variable. The function S(r) has an arbitrary parameter m. S(r) = A + B(d/r)/[1 + m(d/r)]. We use the condition in terms of radial distribution function G(λd,η) containing the self-consistent parameter λ and the condition of continuity at r = d/2 to determine A and B. A different EOS can be obtained with a suitable choice of m and the EOS has a lower root-mean-square deviation than that of Barker—Henderson BH2 for LJ fluids.

  11. RF Sputtering for preparing substantially pure amorphous silicon monohydride

    DOEpatents

    Jeffrey, Frank R.; Shanks, Howard R.

    1982-10-12

    A process for controlling the dihydride and monohydride bond densities in hydrogenated amorphous silicon produced by reactive rf sputtering of an amorphous silicon target. There is provided a chamber with an amorphous silicon target and a substrate therein with the substrate and the target positioned such that when rf power is applied to the target the substrate is in contact with the sputtering plasma produced thereby. Hydrogen and argon are fed to the chamber and the pressure is reduced in the chamber to a value sufficient to maintain a sputtering plasma therein, and then rf power is applied to the silicon target to provide a power density in the range of from about 7 watts per square inch to about 22 watts per square inch to sputter an amorphous silicon hydride onto the substrate, the dihydride bond density decreasing with an increase in the rf power density. Substantially pure monohydride films may be produced.

  12. Preparation of Pure Plutonium Metal Standards for Nondestructive Assay

    SciTech Connect

    S. -T. Hsue; J. E. Stewart; M. S. Krick

    2000-11-01

    To calibrate neutron coincidence and neutron multiplicity counters for passive assay of plutonium, certain detector parameters must be determined. When one is using small plutonium metal samples, biases can be introduced from non-zero multiplication and impurities. This paper describes preparing small, pure plutonium metal standards with well-known geometries to enable accurate multiplication corrections and with acceptably low levels of impurities. To minimize multiplication, these standards are designed as 2-cm-diameter foils with varying thicknesses and masses of 1.4, 3.6, and 7.2 g plutonium. These standards will significantly improve characterization and calibration of neutron coincidence and multiplicity counters. They can also be equally useful for gamma-ray spectrometry and calorimetry. Five sets will be made: four for other US Department of Energy plutonium facilities, and one set to remain at Los Alamos. We will also describe other nondestructive assay standards that are planned for the next few years.

  13. Distribution of G concurrence of random pure states

    NASA Astrophysics Data System (ADS)

    Cappellini, Valerio; Sommers, Hans-Jürgen; Życzkowski, Karol

    2006-12-01

    The average entanglement of random pure states of an N×N composite system is analyzed. We compute the average value of the determinant D of the reduced state, which forms an entanglement monotone. Calculating higher moments of the determinant, we characterize the probability distribution P(D) . Similar results are obtained for the rescaled Nth root of the determinant, called the G concurrence. We show that in the limit N→∞ this quantity becomes concentrated at a single point G⋆=1/e . The position of the concentration point changes if one consider an arbitrary N×K bipartite system, in the joint limit N,K→∞ , with K/N fixed.

  14. Acquired pure red cell aplasia: updated review of treatment

    PubMed Central

    Sawada, Kenichi; Fujishima, Naohito; Hirokawa, Makoto

    2008-01-01

    Pure red cell aplasia (PRCA) is a syndrome characterized by a severe normocytic anaemia, reticulocytopenia, and absence of erythroblasts from an otherwise normal bone marrow. Primary PRCA, or secondary PRCA which has not responded to treatment of the underlying disease, is treated as an immunologically-mediated disease. Although vigorous immunosuppressive treatments induce and maintain remissions in a majority of patients, they carry an increased risk of serious complications. Corticosteroids were used in the treatment of PRCA and this has been considered the treatment of first choice although relapse is not uncommon. Cyclosporine A (CsA) has become established as one of the leading drugs for treatment of PRCA. However, common concerns have been the number of patients treated with CsA who achieve sustained remissions and the number that relapse. This article reviews the current status of CsA therapy and compares it to other treatments for diverse PRCAs. PMID:18510682

  15. Unexpected magnetization in highly pure metal oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Hanna, C. B.; Alanko, Gordon; Beausoleil, Boone; Chess, Jordan; Thurber, Aaron; Punnoose, Alex

    2012-02-01

    We report the synthesis and characterization of a large set of highly pure metal oxide (CeO2, SnO2 and ZnO) nanoparticles of ultra-small size (2-10 nm). While the metal oxide systems in this study are non-magnetic as bulk materials, our prepared nanoparticles possess an unexpected small room-temperature ferromagnetic magnetization on the order of 0.001 emu/g. This magnetization is shown to not be a result of magnetic impurities, and is discussed in terms of modification of the electronic structure and crystal lattice. These nanoparticles were thoroughly characterized in their size and phase by x-ray diffraction, morphology by transmission electron microscopy, chemical state and elemental purity by x-ray photoelectron spectroscopy, electronic bandgap by UV-vis absorption spectroscopy, and magnetic properties by vibrating sample magnetometry and electron paramagnetic resonance.

  16. Irradiation hardening of pure tungsten exposed to neutron irradiation

    NASA Astrophysics Data System (ADS)

    Hu, Xunxiang; Koyanagi, Takaaki; Fukuda, Makoto; Kumar, N. A. P. Kiran; Snead, Lance L.; Wirth, Brian D.; Katoh, Yutai

    2016-11-01

    Pure tungsten samples have been neutron irradiated in HFIR at 90-850 °C to 0.03-2.2 dpa. A dispersed barrier hardening model informed by the available microstructure data has been used to predict the hardness. Comparison of the model predictions and the measured Vickers hardness reveals the dominant hardening contribution at various irradiation conditions. For tungsten samples irradiated in HFIR, the results indicate that voids and dislocation loops contributed to the hardness increase in the low dose region (<0.3 dpa), while the formation of intermetallic second phase precipitation, resulting from transmutation, dominates the radiation-induced strengthening beginning with a relatively modest dose (>0.6 dpa). The precipitate contribution is most pronounced for the HFIR irradiations, whereas the radiation-induced defect cluster microstructure can rationalize the entirety of the hardness increase observed in tungsten irradiated in the fast neutron spectrum of Joyo and the mixed neutron spectrum of JMTR.

  17. Fundamental flame velocities of pure hydrocarbons II : alkadienes

    NASA Technical Reports Server (NTRS)

    Levine, Oscar; Wong, Edgar L; Gerstein, Melvin

    1950-01-01

    Data are presented for the fundamental flame velocities of 10 pure alkadienes that have isolated, conjugated, or cumulative double-bond systems. On the basis of this limited amount of data and the flame velocities previously reported, it is concluded that unsaturation changes the flame velocity in the order alkanes ? alkenes ? alkadienes with isolated double bonds ?= alkadienes with conjugated double bonds ? alkadienes with cumulative double bonds ?= alkynes. There were no significant differences in the flame velocities of cis and trans 1,3-pentadiene. The alkadienes 1,2-pentadiene and 2,3-pentadiene, with different positions of the cumulative double bond in the straight chain, have similar flame velocities. Methyl substitution in a hydrocarbon reduces the flame velocity; the extent of the reduction increases with the degree of unsaturation of the hydrocarbon.

  18. Pure consciousness: distinct phenomenological and physiological correlates of "consciousness itself".

    PubMed

    Travis, F; Pearson, C

    2000-01-01

    This paper explores subjective reports and physiological correlates of the experience of "consciousness itself"--self awareness isolated from the processes and objects of experience during Transcendental Meditation practice. Subjectively, this state is characterized by the absence of the very framework (time, space, and body sense) and content (qualities of inner and outer perception) that define waking experiences. Physiologically, this state is distinguished by the presence of apneustic breathing, autonomic orienting at the onset of breath changes, and increases in the frequency of peak EEG power. A model, called the junction point model, is presented that integrates pure consciousness with waking, dreaming, or sleeping. It could provide a structure to generate a coherent program of research to test the full range of consciousness and so enable us to understand what it means to be fully human.

  19. Pure Consciousness: Distinct Phenomenological and Physiological Correlates of "Consciousness Itself"

    PubMed

    Travis; Pearson

    1999-01-01

    This paper explores subjective reports and physiological correlates of the experience of "consciousness itself" - self awareness isolated from the processes and objects of experience during Transcendental Meditation practice. Subjectively, this state is characterized by the absence of the very framework (time, space, and body sense) and content (qualities of inner and outer perception) that define waking experiences. Physiologically, this state is distinguished by the presence of apneustic breathing, autonomic orienting at the onset of breath changes, and increases in the frequency of peak EEG power. A model, called the junction point model, is presented that integrates pure consciousness with waking, dreaming, or sleeping. It could provide a structure to generate a coherent program of research to test the full range of consciousness and so enable us to understand what it means to be fully human.

  20. Pure Kana agraphia as a manifestation of graphemic buffer impairment.

    PubMed

    Kokubo, K; Suzuki, K; Yamadori, A; Satou, K

    2001-04-01

    We report a left-handed man who demonstrated a pure agraphia limited to words written in Kana characters (syllabograms) following a right putaminal hemorrhage. Writing words in Kanji characters (logograms) was well preserved. His performance in Kana writing was characterized by intact ability to write single syllables, error increase in the second half of words directly proportional to the word length and correct but slow writing of words using kana blocks. Errors were more prominent in Hiragana words than Katakana words which are usually used to transcribe foreign words. Acoustic-grapheme sequencing per se was not impaired as shown by his correct performance in arranging character blocks. These findings suggest selective damage to the graphemic buffer, a module that temporarily maintains the graphemic representation elaborated in previous stages before it is sent to the peripheral systems for its motor realization.

  1. Quantum benchmarks for pure single-mode Gaussian states.

    PubMed

    Chiribella, Giulio; Adesso, Gerardo

    2014-01-10

    Teleportation and storage of continuous variable states of light and atoms are essential building blocks for the realization of large-scale quantum networks. Rigorous validation of these implementations require identifying, and surpassing, benchmarks set by the most effective strategies attainable without the use of quantum resources. Such benchmarks have been established for special families of input states, like coherent states and particular subclasses of squeezed states. Here we solve the longstanding problem of defining quantum benchmarks for general pure Gaussian single-mode states with arbitrary phase, displacement, and squeezing, randomly sampled according to a realistic prior distribution. As a special case, we show that the fidelity benchmark for teleporting squeezed states with totally random phase and squeezing degree is 1/2, equal to the corresponding one for coherent states. We discuss the use of entangled resources to beat the benchmarks in experiments. PMID:24483875

  2. Distribution of G concurrence of random pure states

    SciTech Connect

    Cappellini, Valerio; Zyczkowski, Karol

    2006-12-15

    The average entanglement of random pure states of an NxN composite system is analyzed. We compute the average value of the determinant D of the reduced state, which forms an entanglement monotone. Calculating higher moments of the determinant, we characterize the probability distribution P(D). Similar results are obtained for the rescaled Nth root of the determinant, called the G concurrence. We show that in the limit N{yields}{infinity} this quantity becomes concentrated at a single point G{sub *}=1/e. The position of the concentration point changes if one consider an arbitrary NxK bipartite system, in the joint limit N,K{yields}{infinity}, with K/N fixed.

  3. M553 sphere forming experiment: Pure nickel specimen evaluation

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.; Peters, E. T.

    1973-01-01

    A region or cap of very fine two-dimensional surface growth structure was observed at the top of three of the six pure nickel flight specimens. Such two-dimensional surface growth structures have been observed both on the ground-based specimens and on other surface areas of the flight specimens. However, the fine structures observed on the three flight samples are at least an order of magnitude finer than those previously observed, and resemble similar localized, fine, two-dimensional surface structures observed in both ground and flight specimens for the nickel alloys. The two-dimensional growth areas consist primarily of fine equiaxed grains, specimen SL-2.6, fine dendrites, specimen SL-2.5, or a core of fine equiaxed grains surrounded by a ring of fine dendrites, specimen SL-1.9.

  4. First observation of muonic hyperfine effects in pure deuterium

    SciTech Connect

    Kammel, P.; Breunlich, W.H.; Cargnelli, M.; Mahler, H.G.; Zmeskal, J.; Bertl, W.H.; Petitjean, C.

    1983-11-01

    We discovered a strong hyperfine dependence of the resonant formation process of d..mu..d mesomolecules, while detecting neutrons from muon-catalyzed fusion in pure deuterium gas at 34 K. This new effect enabled us to observe directly transitions between hyperfine states of the ..mu..d atom for the first time and to determine an accurate experimental value for this transition rate. Our analysis demonstrates the importance of hyperfine effects for the quantitative understanding of the mechanism of resonant d..mu..d formation. Moreover, this experiment indicates that the resonant formation process is a powerful tool for a refined spectroscopy of d..mu..d bound states. Finally, the detailed knowledge about mesoatomic and mesomolecular processes obtained in this work provides valuable information for the analysis of experiments on the elementary muon-capture process in deuterium.

  5. Revision of Spin Echoes in Pure Nuclear Quadrupole Resonance

    NASA Astrophysics Data System (ADS)

    Meriles, C. A.

    2001-04-01

    Goldman's spin-1/2 formalism has been used for describing the response of an I=3/2 spin system to a two-pulse sequence in a pure nuclear quadrupole resonance experiment. A detailed analysis of the polarization evolution and quadrupolar echo generation is carried out through the use of explicit expressions for secular homo- and heteronuclear dipolar interactions. In striking contrast with previous studies, it is predicted that Van Vleck's second moments governing a classical solid-echo or Hahn sequence differ from those obtained by equivalent means in magnetic resonance. In fact, it is shown that, although measured moments still complement each other, the combined use of standard sequences does not allow the separate determination of homo- and heteronuclear dipolar contributions to the linewidth, not even in an indirect manner. In this context, the importance and potential usefulness of a crossed coil probe are also briefly discussed.

  6. Pure scaling operators at the integer quantum Hall plateau transition.

    PubMed

    Bondesan, R; Wieczorek, D; Zirnbauer, M R

    2014-05-01

    Stationary wave functions at the transition between plateaus of the integer quantum Hall effect are known to exhibit multifractal statistics. Here we explore this critical behavior for the case of scattering states of the Chalker-Coddington network model with point contacts. We argue that moments formed from the wave amplitudes of critical scattering states decay as pure powers of the distance between the points of contact and observation. These moments in the continuum limit are proposed to be correlation functions of primary fields of an underlying conformal field theory. We check this proposal numerically by finite-size scaling. We also verify the conformal field theory prediction for a three-point function involving two primary fields.

  7. Pure red cell aplasia following autoimmune hemolytic anemia: an enigma.

    PubMed

    Saha, M; Ray, S; Kundu, S; Chakrabarti, P

    2013-01-01

    A 26-year-old previously healthy female presented with a 6-month history of anemia. The laboratory findings revealed hemolytic anemia and direct antiglobulin test was positive. With a diagnosis of autoimmune hemolytic anemia (AIHA), prednisolone was started but was ineffective after 1 month of therapy. A bone marrow trephine biopsy revealed pure red cell aplasia (PRCA) showing severe erythroid hypoplasia. The case was considered PRCA following AIHA. This combination without clear underlying disease is rare. Human parvovirus B19 infection was not detected in the marrow aspirate during reticulocytopenia. The patient received azathioprine, and PRCA improved but significant hemolysis was once again documented with a high reticulocyte count. The short time interval between AIHA and PRCA phase suggested an increased possibility of the evolution of a single disease.

  8. Nanorheology of adsorbed polymer chains immersed in pure solvent.

    PubMed

    Lapique, Fabrice; Montfort, Jean Pierre; Derail, Christophe

    2015-06-01

    Long linear chains of polybutadiene are adsorbed on the two surfaces of a surface force apparatus and immersed in pure tetradecane. The hydrodynamic force was measured by drainage experiments and by frequency sweeps at constant distances. We related the hydrodynamic thickness to the chain dimension. The complex modulus encompasses the shear modulus and, at distances lower than the hydrodynamic thickness, a compression modulus. The compression term was related to the static force which appears when the two adsorbed layers are overlapped. The complex shear modulus was interpreted by a two-components hydrodynamic model proposed by P. Sens et al. We first complemented the theoretical model. Then, our experimental data fit the proposed viscoelastic expressions in the entire range of distances. The storage modulus is supposed to be affected by a residue of free chains and by the dispersion of the loop lengths. PMID:26087919

  9. Light-Induced Metastability in Pure and Hydrogenated Amorphous Silicon

    SciTech Connect

    Queen, D. R.; Liu, X.; Karel, J.; Wang, Q.; Crandall, Richard S.; Metcalf, T. H.; Hellman, F.

    2015-10-01

    Light soaking is found to increase the specific heat C and internal friction Q-1 of pure (a-Si) and hydrogenated (a-Si:H) amorphous silicon. At the lowest temperatures, the increases in C and Q-1 are consistent with an increased density of two-level systems (TLS). The light-induced increase in C persists to room temperature. Neither the sound velocity nor shear modulus change with light soaking indicating that the Debye specific heat is unchanged which suggests that light soaking creates localized vibrational modes in addition to TLS. The increase can be reversibly added and removed by light soaking and annealing, respectively, suggesting that it is related to the Staebler-Wronski effect (SWE), even in a-Si without H, and involves a reversible nanoscale structural rearrangement that is facilitated by, but does not require, H to occur.

  10. Nanosized graphene crystallite induced strong magnetism in pure carbon films.

    PubMed

    Wang, Chao; Zhang, Xi; Diao, Dongfeng

    2015-03-14

    We report strong magnetism in pure carbon films grown by electron irradiation assisted physical vapor deposition in electron cyclotron resonance plasma. The development of graphene nanocrystallites in the amorphous film matrix, and the dependence of the magnetic behavior on amorphous, nanocrystallite and graphite-like structures were investigated. Results were that the amorphous structure shows weak paramagnetism, graphene nanocrystallites lead to strong magnetization, and graphite-like structures corresponded with a lower magnetization. At a room temperature of 300 K, the highest saturation magnetization of 0.37 emu g(-1) was found in the nanosized graphene nanocrystallite structure. The origin of strong magnetism in nanocrystallites was ascribed to the spin magnetic moment at the graphene layer edges.

  11. Homogeneous switching mechanism in pure polyvinylidene fluoride ultrathin films

    NASA Astrophysics Data System (ADS)

    Tian, B. B.; Chen, L. F.; Liu, Y.; Bai, X. F.; Wang, J. L.; Sun, Sh.; Yuan, G. L.; Sun, J. L.; Dkhil, B.; Meng, X. J.; Chu, J. H.

    2015-08-01

    Polarization switching kinetics is one of the key issues for future development of nanoelectronic devices based on ferroelectrics. Up to now, such kinetics still remains poorly studied despite its crucial impact on the device performances. Here, the switching mechanism in 11-nm-thick ferroelectric films of pure homopolymer of polyvinylidene fluoride is investigated. While the usual mechanism involves nucleation and growth of domains, a homogeneous ferroelectric switching is evidenced in such ultrathin films. Indeed, the dependence of the switching rate on applied voltage reveals a critical behavior with the existence of a true threshold field (of ˜0.26 GV /m ) which is required to overcome the energy barrier to reverse the whole polarization homogeneously as suggested by Landau-Ginzburg mean-field theory. Such finding not only supports few previous works but also raises the question on the general aspect of such homogeneous mechanism that might exist in any other nanoscale ferroelectric materials.

  12. Light-induced metastability in pure and hydrogenated amorphous silicon

    NASA Astrophysics Data System (ADS)

    Queen, D. R.; Liu, X.; Karel, J.; Wang, Q.; Crandall, R. S.; Metcalf, T. H.; Hellman, F.

    2015-10-01

    Light soaking is found to increase the specific heat C and internal friction Q-1 of pure (a-Si) and hydrogenated (a-Si:H) amorphous silicon. At the lowest temperatures, the increases in C and Q-1 are consistent with an increased density of two-level systems (TLS). The light-induced increase in C persists to room temperature. Neither the sound velocity nor shear modulus change with light soaking indicating that the Debye specific heat is unchanged which suggests that light soaking creates localized vibrational modes in addition to TLS. The increase can be reversibly added and removed by light soaking and annealing, respectively, suggesting that it is related to the Staebler-Wronski effect (SWE), even in a-Si without H, and involves a reversible nanoscale structural rearrangement that is facilitated by, but does not require, H to occur.

  13. The Case for Research in Pure Physics in Developing Countries

    NASA Astrophysics Data System (ADS)

    Mweene, H. V.

    Science and technology are the keys to modern economic development. But, it has often been argued that poor countries cannot really afford to support research, or that they should at most devote their efforts to applied science only. The scientific knowledge necessary for development would then be partly or wholly obtained from other countries. In this paper, the case will be argued that developing countries cannot afford to leave research, both pure and applied, to the developed countries and that the only way the developing world is going to solve its problems is through development driven by their own research activities. With reference to physics, the importance of research by researchers in poor countries is explained. Lastly, it is outlined how the logistics of doing research under the difficult conditions prevailing in poor countries can be managed.

  14. Modularity of music: evidence from a case of pure amusia

    PubMed Central

    Piccirilli, M.; Sciarma, T.; Luzzi, S.

    2000-01-01

    A case of pure amusia in a 20 year old left handed non-professional musician is reported. The patient showed an impairment of music abilities in the presence of normal processing of speech and environmental sounds. Furthermore, whereas recognition and production of melodic sequences were grossly disturbed, both the recognition and production of rhythm patterns were preserved. This selective breakdown pattern was produced by a focal lesion in the left superior temporal gyrus. This case thus suggests that not only linguistic and musical skills, but also melodic and rhythmic processing are independent of each other. This functional dissociation in the musical domain supports the hypothesis that music components have a modular organisation. Furthermore, there is the suggestion that amusia may be produced by a lesion located strictly in one hemisphere and that the superior temporal gyrus plays a crucial part in melodic processing.

 PMID:10990522

  15. Random unitary evolution model of quantum Darwinism with pure decoherence

    NASA Astrophysics Data System (ADS)

    Balanesković, Nenad

    2015-10-01

    We study the behavior of Quantum Darwinism [W.H. Zurek, Nat. Phys. 5, 181 (2009)] within the iterative, random unitary operations qubit-model of pure decoherence [J. Novotný, G. Alber, I. Jex, New J. Phys. 13, 053052 (2011)]. We conclude that Quantum Darwinism, which describes the quantum mechanical evolution of an open system S from the point of view of its environment E, is not a generic phenomenon, but depends on the specific form of input states and on the type of S-E-interactions. Furthermore, we show that within the random unitary model the concept of Quantum Darwinism enables one to explicitly construct and specify artificial input states of environment E that allow to store information about an open system S of interest with maximal efficiency.

  16. Random unitary evolution model of quantum Darwinism with pure decoherence

    NASA Astrophysics Data System (ADS)

    Balanesković, Nenad

    2015-10-01

    We study the behavior of Quantum Darwinism [W.H. Zurek, Nat. Phys. 5, 181 (2009)] within the iterative, random unitary operations qubit-model of pure decoherence [J. Novotný, G. Alber, I. Jex, New J. Phys. 13, 053052 (2011)]. We conclude that Quantum Darwinism, which describes the quantum mechanical evolution of an open system S from the point of view of its environment E, is not a generic phenomenon, but depends on the specific form of input states and on the type of S- E-interactions. Furthermore, we show that within the random unitary model the concept of Quantum Darwinism enables one to explicitly construct and specify artificial input states of environment E that allow to store information about an open system S of interest with maximal efficiency.

  17. Microbial growth and the effects of mild acidification and preservatives in refrigerated sweetpotato puree

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Refrigerated sweetpotato puree is a convenient form of this vegetable to be used as an ingredient in formulated foods. The microbiology of refrigerated sweetpotato puree during storage for up to 5 weeks, was evaluated. Since puree is made by comminuting steam cooked sweetpotatoes prior to refriger...

  18. About Being Pure and Natural: Understandings of Pre-Service Primary Teachers

    ERIC Educational Resources Information Center

    Lake, David

    2005-01-01

    In an investigation of 149 pre-service primary teachers' understanding of the terms "pure" and "natural," the participants were asked to provide definitions of the two words, and classify various substances including drugs of abuse, pharmaceuticals, nutriceuticals, and household substances as either natural or not natural, and as pure or not pure.…

  19. Entanglement of three-qubit pure states in terms of teleportation capability

    SciTech Connect

    Lee, Soojoon; Joo, Jaewoo; Kim, Jaewan

    2005-08-15

    We define an entanglement measure, called the partial tangle, which represents the residual two-qubit entanglement of a three-qubit pure state. By its explicit calculations for three-qubit pure states, we show that the partial tangle is closely related to the faithfulness of a teleportation scheme over a three-qubit pure state.

  20. Quality of life in purely ocular myasthenia in Japan

    PubMed Central

    2014-01-01

    Background Since there has been no conclusive evidence regarding the treatment of ocular myasthenia, treatment guidelines were recently issued by the European Federation of Neurological Societies/European Neurological Society (EFNS/ENS). However, the therapeutic outcomes concerning the quality-of-life (QOL) of patients with ocular myasthenia are not yet fully understood. Methods We investigated the therapeutic outcomes of patients with purely ocular myasthenia in a multicenter cross-sectional survey in Japan. To evaluate the severity of ocular symptoms, we used the ocular-quantitative MG (QMG) score advocated by Myasthenia Gravis Foundation of America. We used the Japanese translated version of the MG-QOL15, a self-appraised scoring system. Results Of 607 myasthenia gravis (MG) patients with an observation-duration of illness ≥ 2 years, the cases of 123 patients (20%) were limited to ocular muscles (purely ocular myasthenia). During the entire clinical course, 81 patients experienced both ptosis and diplopia, 36 had ptosis alone, and six had diplopia alone. Acetyl-cholinesterase inhibitors and prednisolone were used in 98 and 52 patients, respectively. Treatment improved ocular symptoms, with the mean reduction in ocular-QMG score of 2.3 ± 1.8 points. However, 47 patients (38%) failed to gain minimal manifestation or a better status. Patients with unfavorable outcomes also self-reported severe QOL impairment. Multivariate analyses showed that the pretreatment ocular-QMG score was associated with unfavorable outcomes, but not associated with the patient’s QOL. Conclusion A treatment strategy designed in accord with a patient's ocular presentation must be considered in order to improve ocular symptoms and the patient's QOL. PMID:24996227

  1. Lindane removal by pure and mixed cultures of immobilized actinobacteria.

    PubMed

    Saez, Juliana M; Benimeli, Claudia S; Amoroso, María J

    2012-11-01

    Lindane (γ-HCH) is an organochlorine insecticide that has been widely used in developing countries. It is known to persist in the environment and can cause serious health problems. One of the strategies adopted to remove lindane from the environment is bioremediation using microorganisms. Immobilized cells present advantages over free suspended cells, like their high degradation efficiency and protection against toxins. The aims of this work were: (1) To evaluate the ability of Streptomyces strains immobilized in four different matrices to remove lindane, (2) To select the support with optimum lindane removal by pure cultures, (3) To assay the selected support with consortia and (4) To evaluate the reusability of the immobilized cells. Four Streptomyces sp. strains had previously shown their ability to grow in the presence of lindane. Lindane removal by microorganisms immobilized was significantly higher than in free cells. Specifically immobilized cells in cloth sachets showed an improvement of around 25% in lindane removal compared to the abiotic control. Three strains showed significantly higher microbial growth when they were entrapped in silicone tubes. Strains immobilized in PVA-alginate demonstrated lowest growth. Mixed cultures immobilized inside cloth sachets showed no significant enhancement compared to pure cultures, reaching a maximum removal of 81% after 96 h for consortium I, consisting of the four immobilized strains together. Nevertheless, the cells could be reused for two additional cycles of 96 h each, obtaining a maximum removal efficiency of 71.5% when each of the four strains was immobilized in a separate bag (consortium III). PMID:22840534

  2. Bimodality of Pure Compaction Bands, Buckskin Gulch, Utah

    NASA Astrophysics Data System (ADS)

    Klimczak, C.; Byrne, P. K.

    2015-12-01

    The exposures of the aeolian Navajo Sandstone at Buckskin Gulch, Utah, have received much attention for their spectacular displays of compaction bands. These bands are described as tabular zones of reduced porosity, and are generally categorized into shear-enhanced compaction bands (SECBs), which accommodate equal amounts of compaction and shear strain, and pure compaction bands (PCBs) that have experienced no shearing. PCBs display a wavy or crooked geometry with vertically dipping bands ~1 mm thick. Conversely, SECBs include planar bands up to 1 cm thick with moderate dips defining conjugate geometries. The Buckskin Gulch field site was surveyed, and compaction bands systematically mapped in a sub-area representative of the heaviest deformation. Geologic and structural map units include dune boundaries within the Navajo Sandstone, areas of soft-sediment deformation, and PCBs and SECBs. Mapping shows that SECBs have outcrop characteristics consistent with those reported in previous studies, and are found with varying degrees of deformation in almost all dune units. However, the mapping and compass measurements also reveal a previously unrecognized bimodal pattern of PBC orientation with bands occurring in strands of up to four individual PCBs. One set of orientations only includes single-strand PCBs, whereas the other set is composed of multi-strand PCBs. Both sets of PCBs have nearly vertical dips but their strikes clearly differ from another by up to 25°. Further, PCBs and SECBs show distinct patterns in areas of soft-sediment deformation. Although individual PCB orientations are consistent with the overall trend of PCBs in the area, SECB orientations are chaotic, their growth was clearly affected by the soft-sediment deformation. These field observations are inconsistent with the current understanding of pure compaction band mechanics and so indicate that their growth is more complex than previously thought.

  3. Numerical calculation of the transient behaviour of two pure cross-flow heat exchangers coupled by a circulating flow stream

    NASA Astrophysics Data System (ADS)

    Na Ranong, Chakkrit; Hapke, Jobst; Roetzel, Wilfried

    2010-11-01

    The transient thermal behaviour of a heat shifting system consisting of two pure cross-flow heat exchangers coupled by a circulating flow stream is studied theoretically. A suitable mathematical description of the system is based on the energy balance equation for general flow processes yielding a system of coupled hyperbolic partial differential equations in two dimensions. System responses to perturbations of inlet temperatures and mass flow rates are numerically calculated with an explicit finite difference method. A criterion for the generation of computational grids minimising effects of numerical dispersion and dissipation is applied to the system of coupled pure cross-flow heat exchangers which has not been considered up to now. Due to its internal circulation the coupled system shows a different behaviour compared to single cross-flow heat exchangers like inverse response and oscillatory behaviour to non-oscillating input signals.

  4. Onychomycosis Due to Nondermatophytic Molds

    PubMed Central

    Hwang, Sung Min; Ha, Gyoung Yim

    2012-01-01

    Background Although there have been many studies about onychomycosis due to nondermatophytic molds (NDM), few studies about etiologic agents including NDM in onychomycosis have been reported in Korea. Objective: This study investigated onychomycosis due to NDM in the Gyeongju area of Korea. Objective This study investigated onychomycosis due to NDM in the Gyeongju area of Korea. Methods In the 10-year period from 1999~2009, we reviewed 59 patients with onychomycosis due to NDM. The etiologic agents were identified by cultures on Sabouraud's Dextrose agar with and without cycloheximide. In some cases, internal transcribed spacer sequence analysis was done. NDM isolated considered pathogens when the presence of fungal elements was identified by direct microscopy observation and in follow-up cultures yielding the same fungi. Results Onychomycosis due to NDM comprised 2.3% of all onychomycosis. Of the 59 patients with onychomycosis due to NDM, 84.7% were toenail onychomycosis and 15.3% were fingernail onychomycosis. The incidence rate was highest in the fifth decade (27.1%). The ratio of male to female patients was 1:1.6. The frequency of associated diseases, in descending order, was hypertension, diabetes mellitus, and cerebral hematoma. Distal and lateral subungual onychomycosis (86.4%) was the most common clinical type of onychomycosis. Aspergillus spp. was the most frequently isolated etiologic agent of onychomycosis due to NDM (83.0%). Other causative agents were Scopulariopsis brevicaulis (10.2%), Acremonium spp. (3.4%), Fusarium solani (1.7%), and Chaetomium globosum (1.7%). Conclusion Because of the increase in onychomycosis due to NDM, we suggest the need of a careful mycological examination in patients with onychomycosis. PMID:22577268

  5. Updated analytical solutions of continuity equation for electron beams precipitation - I. Pure collisional and pure ohmic energy losses

    NASA Astrophysics Data System (ADS)

    Dobranskis, R. R.; Zharkova, V. V.

    2015-10-01

    We present updated analytical solutions of continuity equations for power-law beam electrons precipitating in (a) purely collisional losses and (b) purely ohmic losses. The solutions of continuity equation (CE) normalized on electron density presented in Dobranskis & Zharkova are found by method of characteristics eliminating a mistake in the density characteristic pointed out by Emslie et al. The corrected electron beam differential densities (DD) for collisions are shown to have energy spectra with the index of -(γ + 1)/2, coinciding with the one derived from the inverse problem solution by Brown, while being lower by 1/2 than the index of -γ/2 obtained from CE for electron flux. This leads to a decrease of the index of mean electron spectra from -(γ - 2.5) (CE for flux) to -(γ - 2.0) (CE for electron density). The similar method is applied to CE for electrons precipitating in electric field induced by the beam itself. For the first time, the electron energy spectra are calculated for both constant and variable electric fields by using CE for electron density. We derive electron DD for precipitating electrons (moving towards the photosphere, μ = +1) and `returning' electrons (moving towards the corona, μ = -1). The indices of DD energy spectra are reduced from -γ - 1 (CE for flux) to -γ (CE for electron density). While the index of mean electron spectra is increased by 0.5, from -γ + 0.5 (CE for flux) to -γ + 1(CE for electron density). Hard X-ray intensities are also calculated for relativistic cross-section for the updated differential spectra revealing closer resemblance to numerical Fokker-Planck (FP) solutions.

  6. Occupational asthma due to formaldehyde.

    PubMed Central

    Burge, P S; Harries, M G; Lam, W K; O'Brien, I M; Patchett, P A

    1985-01-01

    Bronchial provocation studies on 15 workers occupationally exposed to formaldehyde are described. The results show that formaldehyde exposure can cause asthmatic reactions, and suggest that these are sometimes due to hypersensitivity and sometimes to a direct irritant effect. Three workers had classical occupational asthma caused by formaldehyde fumes, which was likely to be due to hypersensitivity, with late asthmatic reactions following formaldehyde exposure. Six workers developed immediate asthmatic reactions, which were likely to be due to a direct irritant effect as the reactions were shorter in duration than those seen after soluble allergen exposure and were closely related to histamine reactivity. The breathing zone concentrations of formaldehyde required to elicit these irritant reactions (mean 4.8 mg/m3) were higher than those encountered in buildings recently insulated with urea formaldehyde foam, but within levels sometimes found in industry. Images PMID:4023975

  7. Injuries due to falling coconuts.

    PubMed

    Barss, P

    1984-11-01

    Falling coconuts can cause injury to the head, back, and shoulders. A 4-year review of trauma admissions to the Provincial Hospital, Alotau, Milne Bay Province, Papua New Guinea, revealed that 2.5% of such admissions were due to being struck by falling coconuts. Since mature coconut palms may have a height of 24 up to 35 meters and an unhusked coconut may weigh 1 to 4 kg, blows to the head of a force exceeding 1 metric ton are possible. Four patients with head injuries due to falling coconuts are described. Two required craniotomy. Two others died instantly in the village after being struck by dropping nuts.

  8. Bacteremia due to Elizabethkingia meningoseptica

    PubMed Central

    Shinha, Takashi; Ahuja, Rakesh

    2015-01-01

    Elizabethkingia meningoseptica is a nonfermentative gram-negative bacillus that is ubiquitously found in hospital environments and as such, it has been associated with various nosocomial infections. Immunocompromised individuals are particularly at increased risk for developing severe infections due to E. meningoseptica, including bacteremia. E. meningoseptica is resistant to multiple antimicrobials commonly used for gram-negative bacteria and conventional empirical antimicrobials targeting those organisms may result in unfavorable outcome. We report a case of bacteremia due to E. meningoseptica in a patient who necessitated chronic hemodialysis therapy to heighten awareness of this emerging pathogen among patients on hemodialysis. PMID:26793448

  9. Due Process Hearing Case Study

    ERIC Educational Resources Information Center

    Bateman, David F.; Jones, Marni Gail

    2010-01-01

    This article presents a due process hearing case study of a mother who contended that his son, D.J., has been denied of a free and appropriate public education (FAPE) of his School District after being suspended from school. D.J., an elementary student, had been described as hyperactive, inattentive, defiant, and often volatile. He was identified…

  10. MRI appearances of pure epithelial papillary serous borderline ovarian tumours.

    PubMed

    Naqvi, J; Nagaraju, E; Ahmad, S

    2015-04-01

    Borderline epithelial ovarian tumours (BOT) represent 15-20% of all non-benign ovarian epithelial neoplasms. Compared to malignant ovarian tumours, they usually present at a younger age and carry a far superior prognosis. Fertility-conserving surgery is an important treatment option for patients with BOT. Ultrasound and CT are both widely available and play roles in the initial investigation and staging of BOT, respectively. However, lack of soft-tissue contrast limits their ability to characterize BOT. MRI can facilitate recognition of pure epithelial serous BOT (SBOT), including the cystic papillary and surface papillary subtypes. An abundance of hyperintense papillary projections with low signal internal branching and ovarian stroma preservation with a hypointense ovarian capsular margin on T2-weighted imaging are features strongly suggestive of SBOT. In this review we will discuss the general morphological features of SBOT, the benefits and drawbacks of ultrasound and CT in the initial work-up, and the principal MRI features enabling recognition of surface papillary and cystic papillary SBOT.

  11. Optical characterization of phase transitions in pure polymers and blends

    NASA Astrophysics Data System (ADS)

    Mannella, Gianluca A.; Brucato, Valerio; La Carrubba, Vincenzo

    2015-12-01

    To study the optical properties of polymeric samples, an experimental apparatus was designed on purpose and set up. The sample is a thin film enclosed between two glass slides and a PTFE frame, with a very thin thermocouple placed on sample for direct temperature measurement. This sample holder was placed between two aluminum slabs, equipped with a narrow slit for optical measurements and with electrical resistances for temperature control. Sample was enlightened by a laser diode, whereas transmitted light was detected with a photodiode. Measurements were carried out on polyethylene-terephtalate (PET) and two different polyamides, tested as pure polymers and blends. The thermal history imposed to the sample consisted in a rapid heating from ambient temperature to a certain temperature below the melting point, a stabilization period, and then a heating at constant rate. After a second stabilization period, the sample was cooled. The data obtained were compared with DSC measurements performed with the same thermal history. In correspondence with transitions detected via DSC (e.g. melting, crystallization and cold crystallization), the optical signal showed a steep variation. In particular, crystallization resulted in a rapid decrease of transmitted light, whereas melting gave up an increase of light transmitted by the sample. Further variations in transmitted light were recorded for blends, after melting: those results may be related to other phase transitions, e.g. liquid-liquid phase separation. All things considered, the apparatus can be used to get reliable data on phase transitions in polymeric systems.

  12. Hippocampal volume and shape in pure subcortical vascular dementia.

    PubMed

    Kim, Geon Ha; Lee, Jae Hong; Seo, Sang Won; Kim, Jeong Hun; Seong, Joon-Kyung; Ye, Byoung Seok; Cho, Hanna; Noh, Young; Kim, Hee Jin; Yoon, Cindy W; Oh, Seung Jun; Kim, Jae Seung; Choe, Yearn Seong; Lee, Kyung Han; Kim, Sung Tae; Hwang, Jung Won; Jeong, Jee Hyang; Na, Duk L

    2015-01-01

    The purposes of the present study were to explore whether hippocampal atrophy exists in pure subcortical vascular dementia (SVaD) as defined by negative (11)C-Pittsburg compound-B (PiB(-)) positron emission tomography and to compare hippocampal volume and shape between PiB(-) SVaD and PiB positive (PiB(+)) Alzheimer's disease (AD) dementia. Hippocampal volume and shape were compared among 40 patients with PiB(-) SVaD, 34 with PiB(+) AD, and 21 elderly with normal cognitive function (NC). The normalized hippocampal volume of PiB(-) SVaD was significantly smaller than NC but larger than that of PiB(+) AD (NC > PiB(-) SVaD > PiB(+) AD). Both PiB(-) SVaD and PiB(+) AD patients had deflated shape changes in the cornus ammonis (CA) 1 and subiculum compared with NC. However, direct comparison between PiB(-) SVaD and PiB(+) AD demonstrated more inward deformity in the subiculum of the left hippocampus in PiB(+) AD. PiB(-) SVaD patients did have smaller hippocampal volumes and inward shape change on CA 1 and subiculum compared with NC, suggesting that cumulative ischemia without amyloid pathology could lead to hippocampal atrophy and shape changes. PMID:25444608

  13. Water and Air Measures That Make 'PureSense'

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Each day, we read about mounting global concerns regarding the ability to sustain supplies of clean water and to reduce air contamination. With water and air serving as life s most vital elements, it is important to know when these environmental necessities may be contaminated, in order to eliminate exposure immediately. The ability to respond requires an understanding of the conditions impacting safety and quality, from source to tap for water, and from outdoor to indoor environments for air. Unfortunately, the "time-to-know" is not immediate with many current technologies, which is a major problem, given the greater likelihood of risky situations in today s world. Accelerating alert and response times requires new tools, methods, and technologies. New solutions are needed to engage in more rapid detection, analysis, and response. This is the focus of a company called PureSense Environmental, Inc., which evolved out of a unique relationship with NASA. The need for real-time management and operations over the quality of water and air, and the urgency to provide new solutions, were reinforced by the events of September 11, 2001. This, and subsequent events, exposed many of the vulnerabilities facing the multiple agencies tasked with working in tandem to protect communities from harmful disaster. Much has been done since September 11 to accelerate responses to environmental contamination. Partnerships were forged across the public and private sectors to explore, test, and use new tools. Methods and technologies were adopted to move more astutely from proof-of-concept to working solutions.

  14. Optical characterization of phase transitions in pure polymers and blends

    SciTech Connect

    Mannella, Gianluca A.; Brucato, Valerio; La Carrubba, Vincenzo

    2015-12-17

    To study the optical properties of polymeric samples, an experimental apparatus was designed on purpose and set up. The sample is a thin film enclosed between two glass slides and a PTFE frame, with a very thin thermocouple placed on sample for direct temperature measurement. This sample holder was placed between two aluminum slabs, equipped with a narrow slit for optical measurements and with electrical resistances for temperature control. Sample was enlightened by a laser diode, whereas transmitted light was detected with a photodiode. Measurements were carried out on polyethylene-terephtalate (PET) and two different polyamides, tested as pure polymers and blends. The thermal history imposed to the sample consisted in a rapid heating from ambient temperature to a certain temperature below the melting point, a stabilization period, and then a heating at constant rate. After a second stabilization period, the sample was cooled. The data obtained were compared with DSC measurements performed with the same thermal history. In correspondence with transitions detected via DSC (e.g. melting, crystallization and cold crystallization), the optical signal showed a steep variation. In particular, crystallization resulted in a rapid decrease of transmitted light, whereas melting gave up an increase of light transmitted by the sample. Further variations in transmitted light were recorded for blends, after melting: those results may be related to other phase transitions, e.g. liquid-liquid phase separation. All things considered, the apparatus can be used to get reliable data on phase transitions in polymeric systems.

  15. [Pure form of primary ovarian choriocarcinoma. Report of a case].

    PubMed

    Trigueros Velázquez, M; Sereno Coló, J A; Villagrán Urive, J

    1995-08-01

    Ovarian choriocarcinoma from the germ cells is a very rare malignant neoplasia. About the pure form, very few cases have been reported in medical literature. Ovarian choriocarcinoma may originate in three modalities. As primary choriocarcinoma associated to ovarian pregnancy, 2. As a metastatic ovarian carcinoma, from other organs, mainly the uterus, 3. As a primary tumour of germ cells with differentiation to trophoblastic structures. The latter grows in girls or in adult woman, generally young, where necessarily pregnancy has to be excluded. A case is presented of a 21 years old woman, treated at Hospital General "Dr. Miguel Silva", Morelia, Mich. single, without sexual life, with an abdomino-pelvic tumor of 24 cm, from the right ovary and adhered to ascending colon. Beta subunity of chorionic gonadotrophin was 200,000 mUI/ml of blood plasma. At laparotomy a right ovarian tumour, with infiltration to ascending colon, was found; this required total hysterectomy with bilateral salpingo-oophorectomy and right hemicolectomy. After surgery the patient received chemotherapy with cisplatin, bleomicin and vinblastine. After the third treatment cycle and at three months, chorionic gonadotropin became negative; and at four years follow up residual tumoural activity is absent. Largest mortality with these tumors appears during early post-operative stage and it is atributed to the tumour itself or to post-operative complications. If the patient survives this stage and with a good chemotherapeutic program, survival and even complete cure, occurs.

  16. Monogamy of quantum correlations in three-qubit pure states

    NASA Astrophysics Data System (ADS)

    Sudha; Devi, A. R. Usha; Rajagopal, A. K.

    2012-01-01

    The limitation on the shareability of quantum entanglement over several parties, the so-called monogamy of entanglement, is an issue that has received considerable attention from the quantum information community over the last decade. A natural question of interest in this connection is whether monogamy of correlations is true for correlations other than entanglement. This issue is examined here by choosing quantum deficit, proposed by A. K. Rajagopal and R. W. Rendell [Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.66.022104 66, 022104 (2002)], an operational measure of correlations. In addition to establishing the polygamous nature of the class of three-qubit symmetric pure states characterized by two distinct Majorana spinors (to which the W states belong), those with three distinct Majorana spinors [to which Greenberger-Horne-Zeilinger (GHZ) states belong] are shown to either obey or violate monogamy relations. While the generalized W states can be monogamous or polygamous, the generalized GHZ states exhibit monogamy with respect to quantum deficit. The issue of using monogamy conditions based on quantum deficit to witness the states belonging to stochastic local operations and classical communication (SLOCC) inequivalent classes is discussed in light of these results.

  17. Crystallization Evolution of Cold-Sprayed Pure Ni Coatings

    NASA Astrophysics Data System (ADS)

    Cavaliere, P.; Perrone, A.; Silvello, A.

    2016-08-01

    Cold spraying is a coating technology on the basis of aerodynamics and high-speed impact dynamics. Spray particles (usually 1-50 μm in diameter) are accelerated to high velocity (typically 300-1200 m/s) by a high-speed gas (preheated air, nitrogen, or helium) flow that is generated through a convergent-divergent de Laval type nozzle. The coating forms through the intensive plastic deformation of particles impacting on the substrate at temperatures well below the melting point of the spray material. In the present paper, the main processing parameters affecting the crystallization behavior of pure Ni cold spray deposits on IN718 alloy are described. Various experimental conditions have been analyzed: gas temperature and pressure, nozzle to substrate distance. In particular, the study deals with those conditions leading to a strong grain refinement, with an acceptable level of the deposits mechanical properties. In precise spray conditions, a shift toward amorphous phases has been observed and studied. A systematic analysis of microstructural evolution, performed through TEM observations, as a function of processing parameters is presented.

  18. Chimera states in purely local delay-coupled oscillators

    NASA Astrophysics Data System (ADS)

    Bera, Bidesh K.; Ghosh, Dibakar

    2016-05-01

    We study the existence of chimera states in a network of locally coupled chaotic and limit-cycle oscillators. The necessary condition for chimera state in purely local coupled oscillators is discussed. At first, we numerically observe the existence of chimera or multichimera states in the locally coupled Hindmarsh-Rose neuron model. We find that delay time in the nonlinear local coupling reduces the domain of the coherent island in the parameter space of the synaptic coupling strength and time delay, and thus the coherent region can be completely eliminated once the time delay exceeds a certain threshold. We then consider another form of nonlinearity in the local coupling, and the existence of chimera states is observed in the time-delayed Mackey-Glass system and in a Van der Pol oscillator. We also discuss the effect of time delay in local coupling for the existence of chimera states in Mackey-Glass systems. The nonlinearity present in the coupling function plays a key role in the emergence of chimera or multichimera states. A phase diagram for the chimera state is identified over a wide parameter space.

  19. Dirac Node Lines in Pure Alkali Earth Metals.

    PubMed

    Li, Ronghan; Ma, Hui; Cheng, Xiyue; Wang, Shoulong; Li, Dianzhong; Zhang, Zhengyu; Li, Yiyi; Chen, Xing-Qiu

    2016-08-26

    Beryllium is a simple alkali earth metal, but has been the target of intensive studies for decades because of its unusual electron behavior at surfaces. The puzzling aspects include (i) severe deviations from the description of the nearly free-electron picture, (ii) an anomalously large electron-phonon coupling effect, and (iii) giant Friedel oscillations. The underlying origins for such anomalous surface electron behavior have been under active debate, but with no consensus. Here, by means of first-principles calculations, we discover that this pure metal system, surprisingly, harbors the Dirac node line (DNL) that in turn helps to rationalize many of the existing puzzles. The DNL is featured by a closed line consisting of linear band crossings, and its induced topological surface band agrees well with previous photoemission spectroscopy observations on the Be (0001) surface. We further reveal that each of the elemental alkali earth metals of Mg, Ca, and Sr also harbors the DNL and speculate that the fascinating topological property of the DNL might naturally exist in other elemental metals as well. PMID:27610865

  20. Generalized gauge transformations: Pure Yang-Mills case

    SciTech Connect

    Gastmans, R.; Wu, T.T. |

    1998-01-01

    Gauge transformations with Dirac point splitting are systematically discussed for the case of a pure Yang-Mills theory. These generalized gauge transformations are based on two ingredients: a fixed four-vector, which defines the point splitting, and a weight function, which gives an average over the amount of point splitting and which provides a cutoff in momentum space in the direction of the point splitting four-vector. From the requirement that the group property must be satisfied, it is found, starting from a simple ansatz, that an infinitesimal generalized gauge transformation takes the form of an infinite series in the coupling constant. Using induction on the order of the coupling constant, it is shown that all higher-order terms indeed exist and that they can be expressed in terms of the lower-order formulas. That there are such generalized gauge transformations suggests the possibility of a Yang-Mills field theory with mitigated divergences. {copyright} {ital 1997} {ital The American Physical Society}

  1. Universality in pure gravity mediation with vector multiplets

    NASA Astrophysics Data System (ADS)

    Evans, Jason L.; Olive, Keith A.

    2014-12-01

    We consider models of pure gravity mediation in which scalar mass universality is imposed at the grand unified scale and gaugino masses are generated through loops. The minimal model requires a very restricted range for tan β ≈2 - 3 and scalar masses (set by the gravitino mass) of order 300 TeV-1.5 PeV in order to obtain a Higgs mass near 126 GeV. Here we augment the minimal model with one or more sets of vector multiplets (either a 10 and 10 ¯ pair or one or more 5 and 5 ¯ pairs). If coupled to the minimal supersymmetric standard model Higgs, these allow for radiative electroweak symmetry breaking over a significantly larger range of tan β ≈2 - 40 and can fit the Higgs mass with much smaller values of the gravitino mass. In these models, the lightest supersymmetric particle is often the bino, and in order to satisfy the relic density constraint, the bino must be nearly degenerate with either the wino or gluino. In the models considered here, bino gluino coannihilations determine the relic density and since the two are nearly degenerate, LHC limits on the gluino mass are greatly relaxed allowing light relatively gravitinos and gluino masses well within the reach of the LHC.

  2. Anomalous preservation of pure methane hydrate at 1 atm

    USGS Publications Warehouse

    Stern, L.A.; Circone, S.; Kirby, S.H.; Durham, W.B.

    2001-01-01

    Direct measurement of decomposition rates of pure, polycrystalline methane hydrate reveals a thermal regime where methane hydrate metastably `preserves' in bulk by as much as 75 K above its nominal equilibrium temperature (193 K at 1 atm). Rapid release of the sample pore pressure at isothermal conditions between 242 and 271 K preserves up to 93% of the hydrate for at least 24 h, reflecting the greatly suppressed rates of dissociation that characterize this regime. Subsequent warming through the H2O ice point then induces rapid and complete dissociation, allowing controlled recovery of the total expected gas yield. This behavior is in marked contrast to that exhibited by methane hydrate at both colder (193-240 K) and warmer (272-290 K) test conditions, where dissociation rates increase monotonically with increasing temperature. Anomalous preservation has potential application for successful retrieval of natural gas hydrate or hydrate-bearing sediments from remote settings, as well as for temporary low-pressure transport and storage of natural gas.

  3. Ecophysiological and Phylogenetic Studies of Nevskia ramosa in Pure Culture

    PubMed Central

    Stürmeyer, Heike; Overmann, Jörg; Babenzien, Hans-Dietrich; Cypionka, Heribert

    1998-01-01

    During the last 100 years, the neuston bacterium Nevskia ramosa has been described several times. This bacterium forms conspicuous rosette-like microcolonies at the air-water interface. In this study, pure cultures of Nevskia ramosa were obtained for the first time, from a bog lake (strain Soe1, DSMZ 11499T) and a freshwater ditch (strain OL1, DSMZ 11500). The isolates showed special adaptations to life in the epineuston. They formed hydrophobic surface films with a dull appearance. N. ramosa is sensitive to UV radiation but revealed a very effective photorepair mechanism. Exposure to light at a wavelength of 350 nm after UV treatment raised the number of surviving cells by several orders of magnitude. The isolates grew with a broad range of organic substrates. Surface films were formed only in the absence of combined nitrogen; however, nitrogenase activity was not detected. It appears that during growth at the air-water interface the cells benefit from trapping ammonia from the air. The G+C content of the DNA was 67.8 and 69.0 mol% for strains Soe1 and OL1, respectively. The slight difference was confirmed by enterobacterial repetitive intergenic consensus PCR. The 16S rRNA sequences revealed 99.2% similarity. Thus, both isolates belong to the same species. The phylogenetic analysis indicated that Nevskia is a member of the gamma-subclass Proteobacteria that has no known close relatives. PMID:9572968

  4. Ion-induced nucleation of pure biogenic particles.

    PubMed

    Kirkby, Jasper; Duplissy, Jonathan; Sengupta, Kamalika; Frege, Carla; Gordon, Hamish; Williamson, Christina; Heinritzi, Martin; Simon, Mario; Yan, Chao; Almeida, João; Tröstl, Jasmin; Nieminen, Tuomo; Ortega, Ismael K; Wagner, Robert; Adamov, Alexey; Amorim, Antonio; Bernhammer, Anne-Kathrin; Bianchi, Federico; Breitenlechner, Martin; Brilke, Sophia; Chen, Xuemeng; Craven, Jill; Dias, Antonio; Ehrhart, Sebastian; Flagan, Richard C; Franchin, Alessandro; Fuchs, Claudia; Guida, Roberto; Hakala, Jani; Hoyle, Christopher R; Jokinen, Tuija; Junninen, Heikki; Kangasluoma, Juha; Kim, Jaeseok; Krapf, Manuel; Kürten, Andreas; Laaksonen, Ari; Lehtipalo, Katrianne; Makhmutov, Vladimir; Mathot, Serge; Molteni, Ugo; Onnela, Antti; Peräkylä, Otso; Piel, Felix; Petäjä, Tuukka; Praplan, Arnaud P; Pringle, Kirsty; Rap, Alexandru; Richards, Nigel A D; Riipinen, Ilona; Rissanen, Matti P; Rondo, Linda; Sarnela, Nina; Schobesberger, Siegfried; Scott, Catherine E; Seinfeld, John H; Sipilä, Mikko; Steiner, Gerhard; Stozhkov, Yuri; Stratmann, Frank; Tomé, Antonio; Virtanen, Annele; Vogel, Alexander L; Wagner, Andrea C; Wagner, Paul E; Weingartner, Ernest; Wimmer, Daniela; Winkler, Paul M; Ye, Penglin; Zhang, Xuan; Hansel, Armin; Dommen, Josef; Donahue, Neil M; Worsnop, Douglas R; Baltensperger, Urs; Kulmala, Markku; Carslaw, Kenneth S; Curtius, Joachim

    2016-05-25

    Atmospheric aerosols and their effect on clouds are thought to be important for anthropogenic radiative forcing of the climate, yet remain poorly understood. Globally, around half of cloud condensation nuclei originate from nucleation of atmospheric vapours. It is thought that sulfuric acid is essential to initiate most particle formation in the atmosphere, and that ions have a relatively minor role. Some laboratory studies, however, have reported organic particle formation without the intentional addition of sulfuric acid, although contamination could not be excluded. Here we present evidence for the formation of aerosol particles from highly oxidized biogenic vapours in the absence of sulfuric acid in a large chamber under atmospheric conditions. The highly oxygenated molecules (HOMs) are produced by ozonolysis of α-pinene. We find that ions from Galactic cosmic rays increase the nucleation rate by one to two orders of magnitude compared with neutral nucleation. Our experimental findings are supported by quantum chemical calculations of the cluster binding energies of representative HOMs. Ion-induced nucleation of pure organic particles constitutes a potentially widespread source of aerosol particles in terrestrial environments with low sulfuric acid pollution.

  5. Stress Wave Isolation by Purely Mechanical Topological Phononic Crystals

    PubMed Central

    Chaunsali, Rajesh; Li, Feng; Yang, Jinkyu

    2016-01-01

    We present an active, purely mechanical stress wave isolator that consists of short cylindrical particles arranged in a helical architecture. This phononic structure allows us to change inter-particle stiffness dynamically by controlling the contact angles of the cylinders. We use torsional travelling waves to control the contact angles, thereby imposing a desired spatio-temporal stiffness variation to the phononic crystal along the longitudinal direction. Such torsional excitation is a form of parametric pumping in the system, which results in the breakage of the time-reversal symmetry. We report that, in quasi-static sense, the system shows topologically non-trivial band-gaps. However, in a dynamic regime where the pumping effect is significant, these band-gaps become asymmetric with respect to the frequency and wavenumber domains in the dispersion relationship. By using numerical simulations, we show that such asymmetry has a direct correspondence to the topological invariant, i.e., Chern number, of the system. We propose that this asymmetry, accompanied by selective inter-band transition, can be utilized for directional isolation of the stress wave propagating along the phononic crystal. PMID:27477236

  6. Pure and aerated water entry of a flat plate

    NASA Astrophysics Data System (ADS)

    Ma, Z. H.; Causon, D. M.; Qian, L.; Mingham, C. G.; Mai, T.; Greaves, D.; Raby, A.

    2016-01-01

    This paper presents an experimental and numerical investigation of the entry of a rigid square flat plate into pure and aerated water. Attention is focused on the measurement and calculation of the slamming loads on the plate. The experimental study was carried out in the ocean basin at Plymouth University's COAST laboratory. The present numerical approach extends a two-dimensional hydro-code to compute three-dimensional hydrodynamic impact problems. The impact loads on the structure computed by the numerical model compare well with laboratory measurements. It is revealed that the impact loading consists of distinctive features including (1) shock loading with a high pressure peak, (2) fluid expansion loading associated with very low sub-atmospheric pressure close to the saturated vapour pressure, and (3) less severe secondary reloading with super-atmospheric pressure. It is also disclosed that aeration introduced into water can effectively reduce local pressures and total forces on the flat plate. The peak impact loading on the plate can be reduced by half or even more with 1.6% aeration in water. At the same time, the lifespan of shock loading is prolonged by aeration, and the variation of impulse is less sensitive to the change of aeration than the peak loading.

  7. Dirac Node Lines in Pure Alkali Earth Metals.

    PubMed

    Li, Ronghan; Ma, Hui; Cheng, Xiyue; Wang, Shoulong; Li, Dianzhong; Zhang, Zhengyu; Li, Yiyi; Chen, Xing-Qiu

    2016-08-26

    Beryllium is a simple alkali earth metal, but has been the target of intensive studies for decades because of its unusual electron behavior at surfaces. The puzzling aspects include (i) severe deviations from the description of the nearly free-electron picture, (ii) an anomalously large electron-phonon coupling effect, and (iii) giant Friedel oscillations. The underlying origins for such anomalous surface electron behavior have been under active debate, but with no consensus. Here, by means of first-principles calculations, we discover that this pure metal system, surprisingly, harbors the Dirac node line (DNL) that in turn helps to rationalize many of the existing puzzles. The DNL is featured by a closed line consisting of linear band crossings, and its induced topological surface band agrees well with previous photoemission spectroscopy observations on the Be (0001) surface. We further reveal that each of the elemental alkali earth metals of Mg, Ca, and Sr also harbors the DNL and speculate that the fascinating topological property of the DNL might naturally exist in other elemental metals as well.

  8. Pure global acalculia following a left subangular lesion.

    PubMed

    Martory, M D; Mayer, E; Pegna, A J; Annoni, J M; Landis, T; Khateb, A

    2003-08-01

    We describe the case of a right-handed patient who presented a severe acalculia in the context of a pure Gerstmann syndrome following a subangular lesion that spared the left inferior parietal lobule (IPL). The patient showed impairments in Arabic and verbal codes, in number production and comprehension, as well as in numerical facts and problem solving. By using the EC301 calculation battery, semantic and syntactic tasks in Arabic and verbal codes, we tested the different hypotheses raised by the cognitive neuropsychological models of acalculia. The patients' difficulties, which were not associated with a general intellectual deterioration, and those affecting number processing as a particular semantic class, were indicative of a "global acalculia". This deficit, which exceeded the anarithmetia usually described in Gerstmann syndrome following left IPL lesion, suggested that the isolation of this area may constitute a sufficient condition for producing such a global acalculia. These results are discussed in terms of a disorder in the manipulation of mental images of spatially related objects. PMID:12925945

  9. Ion-induced nucleation of pure biogenic particles

    NASA Astrophysics Data System (ADS)

    Kirkby, Jasper; Duplissy, Jonathan; Sengupta, Kamalika; Frege, Carla; Gordon, Hamish; Williamson, Christina; Heinritzi, Martin; Simon, Mario; Yan, Chao; Almeida, João; Tröstl, Jasmin; Nieminen, Tuomo; Ortega, Ismael K.; Wagner, Robert; Adamov, Alexey; Amorim, Antonio; Bernhammer, Anne-Kathrin; Bianchi, Federico; Breitenlechner, Martin; Brilke, Sophia; Chen, Xuemeng; Craven, Jill; Dias, Antonio; Ehrhart, Sebastian; Flagan, Richard C.; Franchin, Alessandro; Fuchs, Claudia; Guida, Roberto; Hakala, Jani; Hoyle, Christopher R.; Jokinen, Tuija; Junninen, Heikki; Kangasluoma, Juha; Kim, Jaeseok; Krapf, Manuel; Kürten, Andreas; Laaksonen, Ari; Lehtipalo, Katrianne; Makhmutov, Vladimir; Mathot, Serge; Molteni, Ugo; Onnela, Antti; Peräkylä, Otso; Piel, Felix; Petäjä, Tuukka; Praplan, Arnaud P.; Pringle, Kirsty; Rap, Alexandru; Richards, Nigel A. D.; Riipinen, Ilona; Rissanen, Matti P.; Rondo, Linda; Sarnela, Nina; Schobesberger, Siegfried; Scott, Catherine E.; Seinfeld, John H.; Sipilä, Mikko; Steiner, Gerhard; Stozhkov, Yuri; Stratmann, Frank; Tomé, Antonio; Virtanen, Annele; Vogel, Alexander L.; Wagner, Andrea C.; Wagner, Paul E.; Weingartner, Ernest; Wimmer, Daniela; Winkler, Paul M.; Ye, Penglin; Zhang, Xuan; Hansel, Armin; Dommen, Josef; Donahue, Neil M.; Worsnop, Douglas R.; Baltensperger, Urs; Kulmala, Markku; Carslaw, Kenneth S.; Curtius, Joachim

    2016-05-01

    Atmospheric aerosols and their effect on clouds are thought to be important for anthropogenic radiative forcing of the climate, yet remain poorly understood. Globally, around half of cloud condensation nuclei originate from nucleation of atmospheric vapours. It is thought that sulfuric acid is essential to initiate most particle formation in the atmosphere, and that ions have a relatively minor role. Some laboratory studies, however, have reported organic particle formation without the intentional addition of sulfuric acid, although contamination could not be excluded. Here we present evidence for the formation of aerosol particles from highly oxidized biogenic vapours in the absence of sulfuric acid in a large chamber under atmospheric conditions. The highly oxygenated molecules (HOMs) are produced by ozonolysis of α-pinene. We find that ions from Galactic cosmic rays increase the nucleation rate by one to two orders of magnitude compared with neutral nucleation. Our experimental findings are supported by quantum chemical calculations of the cluster binding energies of representative HOMs. Ion-induced nucleation of pure organic particles constitutes a potentially widespread source of aerosol particles in terrestrial environments with low sulfuric acid pollution.

  10. Thermal pure quantum states of many-particle systems

    NASA Astrophysics Data System (ADS)

    Hyuga, Masahiko; Sugiura, Sho; Sakai, Kazumitsu; Shimizu, Akira

    2014-09-01

    We generalize the thermal pure quantum (TPQ) formulation of statistical mechanics, in such a way that it is applicable to systems whose Hilbert space is infinite dimensional. Assuming particle systems, we construct the grand-canonical TPQ (gTPQ) state, which is the counterpart of the grand-canonical Gibbs state of the ensemble formulation. A single realization of the gTPQ state gives all quantities of statistical-mechanical interest, with exponentially small probability of error. This formulation not only sheds new light on quantum statistical mechanics but also is useful for practical computations. As an illustration, we apply it to the Hubbard model, on a one-dimensional (1D) chain and on a two-dimensional (2D) triangular lattice. For the 1D chain, our results agree well with the exact solutions over wide ranges of temperature, chemical potential, and the on-site interaction. For the 2D triangular lattice, for which exact results are unknown, we obtain reliable results over a wide range of temperature. We also find that finite-size effects are much smaller in the gTPQ state than in the canonical TPQ state. This also shows that in the ensemble formulation the grand-canonical Gibbs state of a finite-size system simulates an infinite system much better than the canonical Gibbs state.

  11. Theory of Phase Separation and Polarization for Pure Ionic Liquids.

    PubMed

    Gavish, Nir; Yochelis, Arik

    2016-04-01

    Room temperature ionic liquids are attractive to numerous applications and particularly, to renewable energy devices. As solvent free electrolytes, they demonstrate a paramount connection between the material morphology and Coulombic interactions: the electrode/RTIL interface is believed to be a product of both polarization and spatiotemporal bulk properties. Yet, theoretical studies have dealt almost exclusively with independent models of morphology and electrokinetics. Introduction of a distinct Cahn-Hilliard-Poisson type mean-field framework for pure molten salts (i.e., in the absence of any neutral component), allows a systematic coupling between morphological evolution and the electrokinetic phenomena, such as transient currents. Specifically, linear analysis shows that spatially periodic patterns form via a finite wavenumber instability and numerical simulations demonstrate that while labyrinthine type patterns develop in the bulk, lamellar structures are favored near charged surfaces. The results demonstrate a qualitative phenomenology that is observed empirically and thus, provide a physically consistent methodology to incorporate phase separation properties into an electrochemical framework. PMID:26954098

  12. Equation of state, initiation, and detonation of pure ammonium nitrate

    NASA Astrophysics Data System (ADS)

    Robbins, D. L.; Sheffield, S. A.; Dattelbaum, D. M.; Velisavljevic, N.; Stahl, D. B.

    2009-06-01

    Ammonium nitrate (AN) is a widely used fertilizer and mining explosive throughout the world. One of the more common explosives using AN is called ANFO, a mixture of AN prills and fuel oil in a 94:6 ratio by weight. The AN prills are specially made to absorb the fuel oil, forming a mixture that reacts under shock loading through a diffusion-controlled process, resulting in a non-ideal explosive with detonation velocities around 4 km/s. While there are a number of studies on ANFO, there are only a few studies relating to the equation of state (EOS) and detonation properties of pure AN - resulting mainly from studies of accidents that have occurred during transportation of large quantities of AN. We present the results of a series of gas gun-driven plate impact experiments on pressed AN ranging in density from 1.72 to 0.9 g/cm^3. Several of the high density experiments were performed in front surface impact geometry, in which pressed AN disks were built into the projectile front and impacted onto LiF windows. Additional experiments at low density have been done in ``half cell'' multiple magnetic gauge gun experiments. From this work a complete unreacted EOS has been developed, as well as some initiation and detonation information. Additional high pressure x-ray diffraction experiments in diamond anvil cells have provided a static isotherm for AN.

  13. Review: genetics and neuropathology of primary pure dystonia.

    PubMed

    Paudel, R; Hardy, J; Revesz, T; Holton, J L; Houlden, H

    2012-10-01

    Neuropathology has been the key to understanding the aetiology of many neurological disorders such as Alzheimer's disease, Parkinson's disease, frontotemporal degeneration and cerebellar ataxias. Dystonia shares many clinical features with these conditions but research in general, has been unrewarding in providing information on disease processes. Neuropathological studies are few in number and only limited morphological abnormalities have been described. In the genetic literature, dystonia loci are represented as DYT and are assigned ascending numerals chronologically as they are identified. This review will concentrate on the neuropathology of primary pure dystonia, focusing on DYT1 and DYT6 and the correlation between clinical and genetic findings. Research in this area is incomplete and confounded by the rarity of post mortem brain tissue. However, recent findings, indicating a direct interaction between the torsinA (TOR1A) gene responsible for DYT1 and the thanatos-associated domain-containing apoptosis-associated protein 1 (THAP1) gene responsible for DYT6, have important implications in understanding these two entities and also for other members of this group of disorders. PMID:22897341

  14. Pureed cannellini beans can be substituted for shortening in brownies.

    PubMed

    Szafranski, Michele; Whittington, Julianne Allen; Bessinger, Carlton

    2005-08-01

    Studies have shown white beans to be an effective fat replacer in dropped cookies. However, research is needed to determine whether legumes may be an effective replacement for fat in other types of cookies. This study determined the overall acceptability, sensory characteristics, and nutrient content of brownies (bar cookie) made using cannellini beans as a replacement for shortening. Cannellini beans were used to replace 25%, 50%, and 75% of the shortening (by weight) in a control brownie formula. One hundred twenty untrained panelists participated in rating the brownies on a seven-point hedonic scale. Analysis of variance conducted on the acceptability and sensory characteristics indicated a statistically significant effect when replacing fat with beans for acceptability, tenderness, texture, and flavor (P<.05). Post-hoc testing (Scheffe's test) indicated that neither the 25% nor the 50% bean brownies were significantly different from the control in overall acceptability, tenderness, texture, or flavor. Also, the 50% bean brownies, compared with control, had 2.6 g less fat and 21 fewer kcal per 1.4-oz serving. This study demonstrated that pureed cannellini beans can replace as much as 50% of the fat (by weight) in brownies, while yielding an acceptable and more nutritious product.

  15. Intracellular Neural Recording with Pure Carbon Nanotube Probes

    PubMed Central

    Yoon, Inho; Hamaguchi, Kosuke; Borzenets, Ivan V.; Finkelstein, Gleb; Mooney, Richard; Donald, Bruce R.

    2013-01-01

    The computational complexity of the brain depends in part on a neuron’s capacity to integrate electrochemical information from vast numbers of synaptic inputs. The measurements of synaptic activity that are crucial for mechanistic understanding of brain function are also challenging, because they require intracellular recording methods to detect and resolve millivolt- scale synaptic potentials. Although glass electrodes are widely used for intracellular recordings, novel electrodes with superior mechanical and electrical properties are desirable, because they could extend intracellular recording methods to challenging environments, including long term recordings in freely behaving animals. Carbon nanotubes (CNTs) can theoretically deliver this advance, but the difficulty of assembling CNTs has limited their application to a coating layer or assembly on a planar substrate, resulting in electrodes that are more suitable for in vivo extracellular recording or extracellular recording from isolated cells. Here we show that a novel, yet remarkably simple, millimeter-long electrode with a sub-micron tip, fabricated from self-entangled pure CNTs can be used to obtain intracellular and extracellular recordings from vertebrate neurons in vitro and in vivo. This fabrication technology provides a new method for assembling intracellular electrodes from CNTs, affording a promising opportunity to harness nanotechnology for neuroscience applications. PMID:23840357

  16. Stress Wave Isolation by Purely Mechanical Topological Phononic Crystals.

    PubMed

    Chaunsali, Rajesh; Li, Feng; Yang, Jinkyu

    2016-01-01

    We present an active, purely mechanical stress wave isolator that consists of short cylindrical particles arranged in a helical architecture. This phononic structure allows us to change inter-particle stiffness dynamically by controlling the contact angles of the cylinders. We use torsional travelling waves to control the contact angles, thereby imposing a desired spatio-temporal stiffness variation to the phononic crystal along the longitudinal direction. Such torsional excitation is a form of parametric pumping in the system, which results in the breakage of the time-reversal symmetry. We report that, in quasi-static sense, the system shows topologically non-trivial band-gaps. However, in a dynamic regime where the pumping effect is significant, these band-gaps become asymmetric with respect to the frequency and wavenumber domains in the dispersion relationship. By using numerical simulations, we show that such asymmetry has a direct correspondence to the topological invariant, i.e., Chern number, of the system. We propose that this asymmetry, accompanied by selective inter-band transition, can be utilized for directional isolation of the stress wave propagating along the phononic crystal. PMID:27477236

  17. Quantum entanglement swapping of two arbitrary biqubit pure states

    NASA Astrophysics Data System (ADS)

    Xie, ChuanMei; Liu, YiMin; Chen, JianLan; Yin, XiaoFeng; Zhang, ZhanJun

    2016-10-01

    In this paper, the issue of swapping quantum entanglements in two arbitrary biqubit pure states via a local bipartite entangledstate projective measure in the middle node is studied in depth, especially with regard to quantitative aspects. Attention is mainly focused on the relation between the measure and the final entanglement obtained via swapping. During the study, the entanglement of formation (EoF) is employed as a quantifier to characterize and quantify the entanglements present in all involved states. All concerned EoFs are expressed analytically; thus, the relation between the final entanglement and the measuring state is established. Through concrete analyses, the measure demands for getting a certain amount of a final entanglement are revealed. It is found that a maximally entangled final state can be obtained from any two given initial entangled states via swapping with a certain probability; however, a peculiar measure should be performed. Moreover, some distinct properties are revealed and analyzed. Such a study will be useful in quantum information processes.

  18. Geometric local invariants and pure three-qubit states

    SciTech Connect

    Williamson, Mark S.; Ericsson, Marie; Johansson, Markus; Sjoeqvist, Erik; Sudbery, Anthony; Vedral, Vlatko; Wootters, William K.

    2011-06-15

    We explore a geometric approach to generating local SU(2) and SL(2,C) invariants for a collection of qubits inspired by lattice gauge theory. Each local invariant or ''gauge'' invariant is associated with a distinct closed path (or plaquette) joining some or all of the qubits. In lattice gauge theory, the lattice points are the discrete space-time points, the transformations between the points of the lattice are defined by parallel transporters, and the gauge invariant observable associated with a particular closed path is given by the Wilson loop. In our approach the points of the lattice are qubits, the link transformations between the qubits are defined by the correlations between them, and the gauge invariant observable, the local invariants associated with a particular closed path, are also given by a Wilson looplike construction. The link transformations share many of the properties of parallel transporters, although they are not undone when one retraces one's steps through the lattice. This feature is used to generate many of the invariants. We consider a pure three-qubit state as a test case and find we can generate a complete set of algebraically independent local invariants in this way; however, the framework given here is applicable to generating local unitary invariants for mixed states composed of any number of d-level quantum systems. We give an operational interpretation of these invariants in terms of observables.

  19. Dirac Node Lines in Pure Alkali Earth Metals

    NASA Astrophysics Data System (ADS)

    Li, Ronghan; Ma, Hui; Cheng, Xiyue; Wang, Shoulong; Li, Dianzhong; Zhang, Zhengyu; Li, Yiyi; Chen, Xing-Qiu

    2016-08-01

    Beryllium is a simple alkali earth metal, but has been the target of intensive studies for decades because of its unusual electron behavior at surfaces. The puzzling aspects include (i) severe deviations from the description of the nearly free-electron picture, (ii) an anomalously large electron-phonon coupling effect, and (iii) giant Friedel oscillations. The underlying origins for such anomalous surface electron behavior have been under active debate, but with no consensus. Here, by means of first-principles calculations, we discover that this pure metal system, surprisingly, harbors the Dirac node line (DNL) that in turn helps to rationalize many of the existing puzzles. The DNL is featured by a closed line consisting of linear band crossings, and its induced topological surface band agrees well with previous photoemission spectroscopy observations on the Be (0001) surface. We further reveal that each of the elemental alkali earth metals of Mg, Ca, and Sr also harbors the DNL and speculate that the fascinating topological property of the DNL might naturally exist in other elemental metals as well.

  20. Stress Wave Isolation by Purely Mechanical Topological Phononic Crystals

    NASA Astrophysics Data System (ADS)

    Chaunsali, Rajesh; Li, Feng; Yang, Jinkyu

    2016-08-01

    We present an active, purely mechanical stress wave isolator that consists of short cylindrical particles arranged in a helical architecture. This phononic structure allows us to change inter-particle stiffness dynamically by controlling the contact angles of the cylinders. We use torsional travelling waves to control the contact angles, thereby imposing a desired spatio-temporal stiffness variation to the phononic crystal along the longitudinal direction. Such torsional excitation is a form of parametric pumping in the system, which results in the breakage of the time-reversal symmetry. We report that, in quasi-static sense, the system shows topologically non-trivial band-gaps. However, in a dynamic regime where the pumping effect is significant, these band-gaps become asymmetric with respect to the frequency and wavenumber domains in the dispersion relationship. By using numerical simulations, we show that such asymmetry has a direct correspondence to the topological invariant, i.e., Chern number, of the system. We propose that this asymmetry, accompanied by selective inter-band transition, can be utilized for directional isolation of the stress wave propagating along the phononic crystal.

  1. The evolution of pure alexia: a longitudinal study of recovery.

    PubMed

    Behrmann, M; Black, S E; Bub, D

    1990-10-01

    This case report documents the partial recovery, over a 12-month period, of pure alexia in an adult female following a left occipital infarction. Measures of speed and accuracy were obtained on an oral reading and a lexical decision task immediately postonset and then on 10 subsequent occasions. Explicit letter-by-letter reading was observed only during the first week poststroke but a significant effect of word length was seen in all testing sessions. Reading accuracy was relatively good at all stages and reading latency showed a remarkable decrease over time but did not reach normal reading rates. The inability to use higher-order orthographic knowledge, as manifest in the absence of a word superiority effect, was still noted at one year postonset. We therefore concluded that the change in behavior was attributable to increased proficiency in the use of the adaptive letter-by-letter procedure rather than to the resolution of the underlying deficit. It is suggested that longitudinal neurobehavioral studies add to our understanding of the alexic deficit and provide insight into the recovery process. PMID:2285860

  2. Chimera states in purely local delay-coupled oscillators.

    PubMed

    Bera, Bidesh K; Ghosh, Dibakar

    2016-05-01

    We study the existence of chimera states in a network of locally coupled chaotic and limit-cycle oscillators. The necessary condition for chimera state in purely local coupled oscillators is discussed. At first, we numerically observe the existence of chimera or multichimera states in the locally coupled Hindmarsh-Rose neuron model. We find that delay time in the nonlinear local coupling reduces the domain of the coherent island in the parameter space of the synaptic coupling strength and time delay, and thus the coherent region can be completely eliminated once the time delay exceeds a certain threshold. We then consider another form of nonlinearity in the local coupling, and the existence of chimera states is observed in the time-delayed Mackey-Glass system and in a Van der Pol oscillator. We also discuss the effect of time delay in local coupling for the existence of chimera states in Mackey-Glass systems. The nonlinearity present in the coupling function plays a key role in the emergence of chimera or multichimera states. A phase diagram for the chimera state is identified over a wide parameter space.

  3. Passive interferometric symmetries of multimode Gaussian pure states

    NASA Astrophysics Data System (ADS)

    Gabay, Natasha; Menicucci, Nicolas C.

    2016-05-01

    As large-scale multimode Gaussian states begin to become accessible in the laboratory, their representation and analysis become a useful topic of research in their own right. The graphical calculus for Gaussian pure states provides powerful tools for their representation, while this work presents a useful tool for their analysis: passive interferometric (i.e., number-conserving) symmetries. Here we show that these symmetries of multimode Gaussian states simplify calculations in measurement-based quantum computing and provide constructive tools for engineering large-scale harmonic systems with specific physical properties, and we provide a general mathematical framework for deriving them. Such symmetries are generated by linear combinations of operators expressed in the Schwinger representation of U (2 ) , called nullifiers because the Gaussian state in question is a zero eigenstate of them. This general framework is shown to have applications in the noise analysis of continuous-various cluster states and is expected to have additional applications in future work with large-scale multimode Gaussian states.

  4. Pure keratin membrane and fibers from chicken feather.

    PubMed

    Ma, Bomou; Qiao, Xue; Hou, Xiuliang; Yang, Yiqi

    2016-08-01

    In this research, keratin was extracted from the disposable chicken feather using l-cysteine as reducing agent. Then, it was re-dissolved in the sodium carbonate-sodium bicarbonate buffer, and the pure keratin membrane and fiber were fabricated by doctor-blade casting process and wet spinning method, respectively. Scanning electron microscopy (SEM), fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to characterize the chemical and physical properties of resulting powder, membrane and fiber. Compared with the raw chicken feather, the regenerated keratin materials retain its chemical structure and thermal stability, their relative crystallinity is a little different depend on the shaping method, which leads to the difference in moisture regain. The mechanical results show that tensile strength of the keratin membrane researches 3.5MPa, have potential application in biomedical fields. However, the keratin fiber presents low tenacity, i.e. 0.5cN/dtex, this problem should be solved in order to apply the new fiber in textile and material science. PMID:27180293

  5. The synthesis of nanostructured, phase pure catalysts by hydrodynamic cavitation

    SciTech Connect

    Moser, W.R.; Sunstrom, J.E.; Marshik-Geurts, B.J.

    1995-12-01

    A new process for the synthesis of advanced catalytic materials based on performing the synthesis under hydrodynamic cavitation conditions has been discovered. This continuous process for catalyst synthesis resulted in the formation of both supported and unsupported catalysts. The advantage of the process over classical methods of synthesis is that it permits the formation of a wide variety of nanostructured catalysts in exceptionally high phase purities. The synthesis of platinum and palladium catalysts supported on alumina and other supports resulted in high dispersions of the noble metals. The synthesis of alpha, beta- and gamma-bismuth molybdates resulted in catalysts having superior phase purities as compared to several other classical methods of synthesis. The beta-bismuth molybdate was synthesized directly onto Cabosil. These studies showed that the particle size of the active component could be varied from a few manometers to much larger grains. The process enabled the synthesis of other complex metal oxides like perovskites as pure phases. The process uses a commercially available Microfluidizer.

  6. Irradiation hardening of pure tungsten exposed to neutron irradiation

    DOE PAGESBeta

    Hu, Xunxiang; Koyanagi, Takaaki; Fukuda, Makoto; Kumar, N. A. P. Kiran; Snead, Lance L.; Wirth, Brian D.; Katoh, Yutai

    2016-08-26

    In this paper, pure tungsten samples have been neutron irradiated in HFIR at 90–850 °C to 0.03–2.2 dpa. A dispersed barrier hardening model informed by the available microstructure data has been used to predict the hardness. Comparison of the model predictions and the measured Vickers hardness reveals the dominant hardening contribution at various irradiation conditions. For tungsten samples irradiated in HFIR, the results indicate that voids and dislocation loops contributed to the hardness increase in the low dose region (<0.3 dpa), while the formation of intermetallic second phase precipitation, resulting from transmutation, dominates the radiation-induced strengthening beginning with a relativelymore » modest dose (>0.6 dpa). Finally, the precipitate contribution is most pronounced for the HFIR irradiations, whereas the radiation-induced defect cluster microstructure can rationalize the entirety of the hardness increase observed in tungsten irradiated in the fast neutron spectrum of Joyo and the mixed neutron spectrum of JMTR.« less

  7. Ion-induced nucleation of pure biogenic particles.

    PubMed

    Kirkby, Jasper; Duplissy, Jonathan; Sengupta, Kamalika; Frege, Carla; Gordon, Hamish; Williamson, Christina; Heinritzi, Martin; Simon, Mario; Yan, Chao; Almeida, João; Tröstl, Jasmin; Nieminen, Tuomo; Ortega, Ismael K; Wagner, Robert; Adamov, Alexey; Amorim, Antonio; Bernhammer, Anne-Kathrin; Bianchi, Federico; Breitenlechner, Martin; Brilke, Sophia; Chen, Xuemeng; Craven, Jill; Dias, Antonio; Ehrhart, Sebastian; Flagan, Richard C; Franchin, Alessandro; Fuchs, Claudia; Guida, Roberto; Hakala, Jani; Hoyle, Christopher R; Jokinen, Tuija; Junninen, Heikki; Kangasluoma, Juha; Kim, Jaeseok; Krapf, Manuel; Kürten, Andreas; Laaksonen, Ari; Lehtipalo, Katrianne; Makhmutov, Vladimir; Mathot, Serge; Molteni, Ugo; Onnela, Antti; Peräkylä, Otso; Piel, Felix; Petäjä, Tuukka; Praplan, Arnaud P; Pringle, Kirsty; Rap, Alexandru; Richards, Nigel A D; Riipinen, Ilona; Rissanen, Matti P; Rondo, Linda; Sarnela, Nina; Schobesberger, Siegfried; Scott, Catherine E; Seinfeld, John H; Sipilä, Mikko; Steiner, Gerhard; Stozhkov, Yuri; Stratmann, Frank; Tomé, Antonio; Virtanen, Annele; Vogel, Alexander L; Wagner, Andrea C; Wagner, Paul E; Weingartner, Ernest; Wimmer, Daniela; Winkler, Paul M; Ye, Penglin; Zhang, Xuan; Hansel, Armin; Dommen, Josef; Donahue, Neil M; Worsnop, Douglas R; Baltensperger, Urs; Kulmala, Markku; Carslaw, Kenneth S; Curtius, Joachim

    2016-05-26

    Atmospheric aerosols and their effect on clouds are thought to be important for anthropogenic radiative forcing of the climate, yet remain poorly understood. Globally, around half of cloud condensation nuclei originate from nucleation of atmospheric vapours. It is thought that sulfuric acid is essential to initiate most particle formation in the atmosphere, and that ions have a relatively minor role. Some laboratory studies, however, have reported organic particle formation without the intentional addition of sulfuric acid, although contamination could not be excluded. Here we present evidence for the formation of aerosol particles from highly oxidized biogenic vapours in the absence of sulfuric acid in a large chamber under atmospheric conditions. The highly oxygenated molecules (HOMs) are produced by ozonolysis of α-pinene. We find that ions from Galactic cosmic rays increase the nucleation rate by one to two orders of magnitude compared with neutral nucleation. Our experimental findings are supported by quantum chemical calculations of the cluster binding energies of representative HOMs. Ion-induced nucleation of pure organic particles constitutes a potentially widespread source of aerosol particles in terrestrial environments with low sulfuric acid pollution. PMID:27225125

  8. Eruptive shearing of tube pumice: pure and simple

    NASA Astrophysics Data System (ADS)

    Dingwell, Donald B.; Lavallée, Yan; Hess, Kai-Uwe; Flaws, Asher; Marti, Joan; Nichols, Alexander R. L.; Gilg, H. Albert; Schillinger, Burkhard

    2016-09-01

    Understanding the physicochemical conditions extant and mechanisms operative during explosive volcanism is essential for reliable forecasting and mitigation of volcanic events. Rhyolitic pumices reflect highly vesiculated magma whose bubbles can serve as a strain indicator for inferring the state of stress operative immediately prior to eruptive fragmentation. Obtaining the full kinematic picture reflected in bubble population geometry has been extremely difficult, involving dissection of a small number of delicate samples. The advent of reliable high-resolution tomography has changed this situation radically. Here we demonstrate via the use of tomography how a statistically powerful picture of the shapes and connectivity of thousands of individual bubbles within a single sample of tube pumice emerges. The strain record of tube pumice is modelled using empirical models of bubble geometry and liquid rheology, reliant on a constraint of magmatic water concentration. FTIR analysis reveals an imbalance in water speciation, suggesting post-eruption hydration, further supported by hydrogen and oxygen isotope measurements. Our work demonstrates that the strain recorded in the tube pumice dominated by simple shear (not pure shear) in the late deformational history of vesicular magma before eruption. This constraint in turn implies that magma ascent is conditioned by a velocity gradient (across the conduit) at the point of origin of tube pumice. Magma ascent accompanied by simple shear should enhance high eruption rates inferred independently for these highly viscous systems.

  9. High Strength, Large Core Pure Silica Fibers For Laser Surgery

    NASA Astrophysics Data System (ADS)

    Skutnik, B. J.; Hodge, M. H.; Clarkin, J. P.

    1988-06-01

    Recently many researchers, doctors and instrument companies have begun developing fiber optic laser power delivery systems to accomplish less traumatic surgery or localized irradiation treatment(1). With high power levels, particularly in short bursts, large core fibers are needed to keep the power densities from approaching the damage threshold of silica. Among the many advantages of using optical fibers in laser surgery are the following: microsurgery can be employed, trauma is reduced, access to interior through catheter introduction into vascular, gastrointestinal or respiratory tracts, accurate application of laser power through a flexible lightweight medium to provide localized irradiation as well as surgical removal, and the devices are sterilizable and of moderate cost permitting one-time use (disposable) probes. To achieve these wonderful gains in surgical procedures, the optical fibers must satisfy many optical and mechanical requirements. In use the optical fibers are often required to bend around curves or obstructions to reach the desired application area. Large tensile stresses can occur on the outer radius of the bent fiber, especially with large core fibers, thus high strength fibers are needed. Furthermore, since body fluids are primarily water, stress corrosion and fatigue(2-6) will occur. Therefore, the fibers should have excellent fatigue resistance as well as high strength. This paper further describes these requirements and presents details about an optical fiber which meets these requirements and provides additional very useful properties. These fibers with pure silica cores are called Hard Clad Silica, HCS*, fibers because of their hard bonded cladding over silica structure.

  10. Pyrrolizidine alkaloids of Echium vulgare honey found in pure pollen.

    PubMed

    Boppré, Michael; Colegate, Steven M; Edgar, John A

    2005-02-01

    The pyrrolizidine alkaloids previously identified in floral honey attributed to Echium vulgare (Boraginaceae) have been detected (8000-14 000 ppm) in pure pollen collected from the anthers of Echium vulgare. Pyrrolizidine alkaloids and/or their N-oxides were isolated from the aqueous acid extracts of pollen by use of strong cation-exchange, solid-phase extraction and identified by liquid chromatographic/mass spectrometric (LCMS) analysis. The pyrrolizidine alkaloids in the pollen are present mainly as the N-oxides. In addition to seven previously described pyrrolizidine alkaloids and/or their N-oxides (echimidine, acetylechimidine, uplandicine, 9-O-angelylretronecine, echiuplatine, leptanthine, and echimiplatine), one unidentified (echivulgarine), but previously found in honey, and two previously undescribed (vulgarine and 7-O-acetylvulgarine) pyrrolizidine alkaloids and/or their N-oxides were identified in the pollen. Tentative structures for these unidentified pyrrolizidine alkaloids are proposed on the basis of the mass spectrometric data and biogenetic considerations. The implications of these results for identifying the source and subsequent concentrations of pyrrolizidine alkaloids in honeys and commercial bee pollen are briefly discussed. PMID:15686407

  11. Mevva ion source operated in purely gaseous mode

    SciTech Connect

    Yushkov, G.Y.; MacGill, R.A.; Brown, I. G.

    2003-03-27

    We have operated a vacuum arc ion source in such a way as to form beams of purely gaseous ions. The vacuum arc configuration that is conventionally used to produce intense beams of metal ions was altered so as to form gaseous ion beams, with only minimal changes to the external circuitry and no changes at all internally to the ion source. In our experiments we formed beams from oxygen (O{sup +} and O{sub 2}{sup +}), nitrogen (N{sup +} and N{sub 2}{sup +}), argon (Ar{sup +}) and carbon dioxide (C{sup +}, CO{sub 2}{sup +}, O{sup +} and O{sub 2}{sup +}) at extraction voltage of 2 to 50 kV. We used a pulsed mode of operation, with beam pulses approximately 50 milliseconds long and repetition rate 10 pulses per second, for a duty cycle of about 50%. Downstream ion beam current as measured by a 5 cm diameter Faraday cup was typically 0.5 mA pulse or about 250 {micro}A time averaged. This time averaged beam current is very similar to that obtained for metal ions when the source is operated in the usual vacuum arc mode. Here we describe the modifications made to the source and the results of our investigations.

  12. The formation of pure anorthosite on the Moon

    NASA Astrophysics Data System (ADS)

    Piskorz, Danielle; Stevenson, David J.

    2014-09-01

    The giant impact hypothesis for the origin of the Moon points to the creation of a hot, young Moon, likely with a global magma ocean. Such a magma ocean would produce a flotation crust of plagioclase crystals, or an anorthositic crust. Early calculations of the expected anorthosite content of the lunar highlands crust did not match initial measurements of Apollo samples, and more recently have not matched Clementine measurements or SELENE measurements, because they assumed interstitial melt would freeze. We consider a physical model of a magma ocean with an accumulating flotation lid, and find that significant escape of melt can take place for reasonable physical parameters and timescales of melt migration, even allowing for the inhibiting effect of plausible compaction viscosities. This model permits more nearly pure lunar anorthosites, consistent with observations. The model encounters some difficulty in explaining the expulsion of melt for the near-surface crust (up to five-kilometers’ depth) that presumably dominates the Apollo samples, suggesting that impact mixing and tidal heating are needed to explain the discrepancy.

  13. First Reported Case of Primary Intrahepatic Cholangiocarcinoma with Pure Squamous Cell Histology: A Case Report

    PubMed Central

    Lubana, Sandeep Singh; Singh, Navdeep; Seligman, Barbara; Tuli, Sandeep S.; Heimann, David M.

    2015-01-01

    : Squamous cell carcinoma of the biliary tree is very rare and the majority of tumors are adenocarcinomas. Cholangiocarcinomas containing a squamous cell component have a poor prognosis due to its aggressive behavior. However, prognosis of cholangiocarcinoma with pure SCC histology is unknown because this is the first case in the literature. PMID:26158884

  14. A Pilot Randomized Placebo Controlled Trial of Electroacupuncture for Women with Pure Stress Urinary Incontinence

    PubMed Central

    Xu, Huanfang; Liu, Baoyan; Wu, Jiani; Du, Ruosang; Liu, Xiaoxu; Yu, Jinna; Liu, Zhishun

    2016-01-01

    Background Acupuncture is a potential conservative therapy for women with stress urinary incontinence (SUI). There is limited evidence to support its effectiveness due to the poor quality of existing studies. Methods We performed a pilot randomized, controlled trial to preliminarily assess the efficacy of electroacupuncture (EA) in women with pure SUI. A total of 80 women with pure SUI were randomly assigned to receive EA with deep needling at BL33 and BL35 (n = 40) or sham EA with non-penetrating needling at sham acupoints (n = 40) three sessions per week for 6 weeks. The women were followed for 24 weeks. The primary outcome was the change from baseline in the amount of urine leakage measured by a 1-hour pad test after 6 weeks. The secondary outcomes included the 72-hour incontinence episode frequency (IEF), International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) score, and patient self-evaluation of therapeutic effect. Adverse events (AEs) were monitored throughout the trial. Results The median decrease from baseline of urine leakage measured by the 1-hour pad test was 2.5 g [interquartile range (IQR): 1.80–14.6 in the EA group, which was greater than the median decrease of 0.05 g (IQR: -2.80–+0.50) in the sham EA group after 6 weeks (p<0.01). The differences between groups in the decrease from baseline of 72-hour IEF became statistically significant at week 30 with a median decrease of 3.25 g (IQR: 1.25–5.69) in the EA group, and a median decrease of 1.00 g (IQR: -0.69–+2.88) in the sham EA group (p = 0.01). The participants in the EA group showed greater decreases in ICIQ-SF score and higher ratings in the help they received from the treatment than those in the sham EA group at weeks 6,18 and 30 (all p<0.05). No obvious AEs were observed in either group. Conclusion EA may effectively and safely relieve urinary incontinence symptoms and improve quality of life in women with pure SUI. EA demonstrated more than a placebo effect. Since

  15. Radioactivity determination of sealed pure beta-sources by surface dose measurements and Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Choi, Chang Heon; Jung, Seongmoon; Choi, Kanghyuk; Son, Kwang-Jae; Lee, Jun Sig; Ye, Sung-Joon

    2016-04-01

    This study aims to determine the activity of a sealed pure beta-source by measuring the surface dose rate using an extrapolation chamber. A conversion factor (cGy s-1 Bq-1), which was defined as the ratio of surface dose rate to activity, can be calculated by Monte Carlo simulations of the extrapolation chamber measurement. To validate this hypothesis the certified activities of two standard pure beta-sources of Sr/Y-90 and Si/P-32 were compared with those determined by this method. In addition, a sealed test source of Sr/Y-90 was manufactured by the HANARO reactor group of KAERI (Korea Atomic Energy Research Institute) and used to further validate this method. The measured surface dose rates of the Sr/Y-90 and Si/P-32 standard sources were 4.615×10-5 cGy s-1 and 2.259×10-5 cGy s-1, respectively. The calculated conversion factors of the two sources were 1.213×10-8 cGy s-1 Bq-1 and 1.071×10-8 cGy s-1 Bq-1, respectively. Therefore, the activity of the standard Sr/Y-90 source was determined to be 3.995 kBq, which was 2.0% less than the certified value (4.077 kBq). For Si/P-32 the determined activity was 2.102 kBq, which was 6.6% larger than the certified activity (1.971 kBq). The activity of the Sr/Y-90 test source was determined to be 4.166 kBq, while the apparent activity reported by KAERI was 5.803 kBq. This large difference might be due to evaporation and diffusion of the source liquid during preparation and uncertainty in the amount of weighed aliquot of source liquid. The overall uncertainty involved in this method was determined to be 7.3%. We demonstrated that the activity of a sealed pure beta-source could be conveniently determined by complementary combination of measuring the surface dose rate and Monte Carlo simulations.

  16. Structure and electronic properties of pure and nitrogen doped nanocrystalline tungsten oxide thin films

    NASA Astrophysics Data System (ADS)

    Vemuri, Venkata Rama Sesha Ravi Kumar

    Tungsten oxide (WO3) is a multifunctional material which has applications in electronics, sensors, optoelectronics, and energy-related technologies. Recently, electronic structure modification of WO3 to design novel photocatalysts has garnered significant attention. However, a fundamental understanding of nitrogen-induced changes in the structure, morphology, surface/ interface chemistry, and electronic properties of WO 3 is a prerequisite to producing materials with the desired functionality and performance. Also, understanding the effect of thermodynamic and processing variables is highly desirable in order to derive the structure-property relationships in the W-O/W-O-N material system. The present work was, therefore, focused on studying the effects of processing parameters on the microstructure, optical properties, electrical conductivity, and electronic structures of pure and nitrogen-doped (N-doped) WO3 films grown by sputter deposition. Efforts were made to understand the properties and phenomena of pure and N-doped WO3 at reduced dimensionality (i.e., nanoscale dimensions). The results and analyses indicate that the growth temperature (Ts) has a significant effect on the microstructure of WO3 films. The grain size increases from 9 to 50 nm coupled with a phase transformation in the following sequence: amorphous (a) to monoclinic (m) to tetragonal (t) with increasing Ts (25--500°C). The nanocrystalline t-WO 3 films exhibit a strong (001) texturing. The band gap narrowing from 3.25 to 2.92 eV with grain size occurs due to quantum confinement effects. Correlated with the structure and optical properties, electrical conductivity also increases. Physical properties such as thickness, grain size, and density are also sensitive to oxygen/ nitrogen partial pressure during W-O/W-O-N sample fabrications. A direct relationship between film density and band gap is evident in nanocrystalline t-WO3 films grown at various oxygen pressures. It is observed that nitrogen

  17. Synthesis and Characterization of Pure and Doped Ceria Films by Sol-Gel and Sputtering

    SciTech Connect

    Koch, K.T.; Saraf, L.

    2004-01-01

    Pure and doped Ceria are known for their ability to gain or lose Oxygen, which is of interest to the Solid Oxide Fuel Cell (SOFC) and catalyst community. Current efforts are focused in SOFCs to reduce the operating temperature of the cell while maintaining ionic conduction. Ceria is known for its high ionic conductivity in the intermediate temperature region. (600-800° C) We have prepared pure and doped Ceria films by Sol-gel and magnetron sputtering methods. Enhanced grain-boundary contribution in the conductivity can be studied in the Sol-gel process due to excellent control over the synthesis conditions, which enabled us to control the average grain size. Sputtered films were grown and investigated as a prelude to possible multi-layered CeO2 structures in the near future. These films were characterized by X-ray diffraction (XRD), nuclear reaction analysis (NRA), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and Oxygen conduction measurements. We have observed greater volume diffusion in nanocrystalline Ceria compared to bulk polycrystalline films as a result of low density. Near surface diffusion properties with increasing temperature indicate a decrease in the volume diffusion as a result of grain growth. However, a linear increase in O2 content at ~600nm depth was observed and can be correlated to the redistribution of O2 in the samples. Surface roughness of <111> and <200> oriented Ceria films on Al2O3 and YSZ was observed to be 0.13nm and 0.397nm, respectively. In the case of Ceria grown on YSZ, structural properties from XRD results showed a highly oriented structure with cube on cube growth. XRD results from Ceria grown on Al2O3 showed an oriented structure whose degree of orientation appeared to be partially dependent on substrate temperature. Preliminary XPS results indicate reduction in Ceria from the Ce4+ to Ce3+ state near the surface.

  18. Optical characterization of pure and chemically modified chitosan bio-films

    NASA Astrophysics Data System (ADS)

    Nosal, William H.

    The purpose of this work was to apply spectroscopic ellipsometry (SE) to the study of monolayer thick chemically modified surfaces and then study the protein attachment or rejection of these films. Optical properties of spin-cast pure and chemically modified chitosan films have been determined in the infrared (IR), visible (vis), ultraviolet (UV), and vacuum ultraviolet (VUV) regions of the spectrum using spectroscopic ellipsometry (SE). Vis-SE data were used to monitor protein attachment or nonattachment to the surface of the chemically modified chitosan using real-time SE. Optical constants for the UV-Vis-near IR spectra from 130nm to 1700nm were determined on dried samples. Optical constants were modeled using Cauchy dispersion forms combined with Lorentzian oscillator models in the absorptive shorter wavelength regions. Infrared refraction index and extinction coefficients from 750cm -1 to 4000cm-1 were determined using ellipsometric data fits to dispersion models based on harmonic oscillators. This modeling determined that optical anisotropy was present and measurable over all wavelength regions of ellipsometric data. VUV adsorption was accounted for by including Gaussian and Tauc-Lorentz shaped oscillators in the optical model. IR-SE and VUV-SE data were used to confirm that chemical modifications to the surface occurred. IR spectra are well known for identifying resonant chemical bonds. However, VUV-SE simultaneously offers resonances for chemical identifications and high surface sensitivity due to shallow depth of optical penetration. To obtain additional information on the micro-scale and nano-scale surface structure, tapping mode AFM imaging was employed to determine morphology and roughness information of dry modified and pure spin-cast chitosan films.

  19. Photolysis of Pure Solid O3 and O2 Films at 193nm

    NASA Technical Reports Server (NTRS)

    Raut, U.; Loeffler, M. J.; Fama, M.; Baragiola, R. A.

    2011-01-01

    We studied quantitatively the photochemistry of solid O3 and O2 films at 193 nm and 22 K with infrared spectroscopy and microgravimetry. Photolysis of pure ozone destroyed O3, but a small amount of ozone remained in the film at high fluence. Photolysis of pure O2 produced O3 in an amount that increased with photon fluence to a stationary level. For both O2 and O3 films, the O3:O2 ratio at large fluences is ?0.07, about two orders of magnitude larger than those obtained in gas phase photolysis. This enhancement is attributed to the increased photodissociation of O2 due to photoabsorption by O2 dimers, a process significant at solid-state densities. We obtain initial quantum yield for ozone synthesis from solid oxygen, phi (O3) = 0.24 0.06, and quantum yields for destruction of O3 and O2 in their parent solids, phi(-O3) = 1.0 0.2 and phi(-O2) = 0.36 0.1. Combined with known photoabsorption cross sections, we estimate probabilities for geminate recombination of 0.5 0.1 for O3 fragments and 0.88 0.03 for oxygen atoms from O2 dissociation. Using a single parameter kinetic model, we deduce the ratio of reaction cross sections for an O atom with O2 vs. O3 to be 0.1 0.2. The general good agreement of the model with the data suggests the validity of the central assumption of efficient energy and spin relaxation of photofragments in the solid prior to their reactions with other species.

  20. The elevated temperature tensile properties of S-200E commercially pure beryllium

    SciTech Connect

    Henshall, G.A.; Torres, S.G.; Hanafee, J.E.

    1995-09-01

    The tensile properties of commercially pure beryllium are sensitive to temperature, impurity content, texture, grain size, and prior processing. Therefore, tensile tests have been conducted using the commercially pure S-200E Be commonly employed at Lawrence Livermore National Laboratory. These experiments were performed at temperatures ranging from 300 to 1100{degrees}C in the longitudinal and transverse orientations at the quasi-static strain rate of 5.5 x 10{sup -4} s{sup -1}. The results of these experiments reveal that the stress-strain curve is smooth, ie. without yield points or serrations, over the entire temperature range studied. The yield stress (YS) and ultimate tensile stress (UTS) decrease monotonically with increasing temperature. Similar strengths were measured for both the longitudinal and transverse orientations, with the latter exhibiting slightly lower YS and UTS values. The measured failure elongation (e{sub f}) vs. temperature curve is complex due to the competing effects of increasing basal-plane fracture stress with increasing temperature combined with the presence of hot shortness at intermediate temperatures. The latter is believed to be caused, at least partially, by the presence of free aluminum impurities at the grain boundaries. This hypothesis is supported by the measured increase in e{sub f} at 700{degrees}C following a 100-hr anneal at 750{degrees}C, which would remove free Al from the grain boundaries. Texture also was found to influence e{sub f}. The favorable orientation of the basal planes for initiation and propagation of cleavage cracks in longitudinal specimens results in a significantly decreased failure elongation compared with the transverse orientation. The effects of testing temperature and specimen orientation on the reduction in area were found to be similar to those described for e{sub f}.