8,653 research outputs found

    A new view of quiet-Sun topology from Hinode/SOT

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    Context. With the recent launch of the Hinode satellite our view of the nature and evolution of quiet-Sun regions has been improved. In light of the new high resolution observations, we revisit the study of the quiet Sun's topological nature. Aims. Topology is a tool to explain the complexity of the magnetic field, the occurrence of reconnection processes, and the heating of the corona. This Letter aims to give new insights to these different topics. Methods. Using a high-resolution Hinode/SOT observation of the line-of-sight magnetic field on the photosphere, we calculate the three dimensional magnetic field in the region above assuming a potential field. From the 3D field, we determine the existence of null points in the magnetic configuration. Results. From this model of a continuous field, we find that the distribution of null points with height is significantly different from that reported in previous studies. In particular, the null points are mainly located above the bottom boundary layer in the photosphere (54%) and in the chromosphere (44%) with only a few null points in the corona (2%). The density of null points (expressed as the ratio of the number of null points to the number of photospheric magnetic fragments) in the solar atmosphere is estimated to be between 3% and 8% depending on the method used to identify the number of magnetic fragments in the observed photosphere. Conclusions. This study reveals that the heating of the corona by magnetic reconnection at coronal null points is unlikely. Our findings do not rule out the heating of the corona at other topological features. We also report the topological complexity of the chromosphere as strongly suggested by recent observations from Hinode/SOT

    Ultrasonic scanning system for in-place inspection of brazed tube joints

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    A miniaturized ultrasonic scanning system for nondestructive in-place, non-immersion testing of brazed joints in stainless-steel tubing is described. The system is capable of scanning brazed tube joints, with limited clearance access, in 1/4 through 5/8 inch union, tee, elbow and cross configurations. The system has the capability to detect defective conditions now associated with material density changes in addition to those which are depended upon density variations. The system includes a miniaturized scanning head assembly that fits around a tube joint and rotates the transducer around and down the joint in a continuous spiral motion. The C-scan recorder is similar in principle to conventional models except that it was specially designed to track the continuous spiral scan of the tube joint. The scanner and recorder can be operated with most commercially available ultrasonic flaw detectors

    Ultrasonic scanning system for in-place inspection of brazed-tube joints

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    System detects defects of .051 cm in diameter and larger. System incorporates scanning head assembly including boot enclosed transducer, slip ring assembly, drive mechanism, and servotransmitter. Ultrasonic flaw detector, prototype recorder, and special recorder complete system

    Some Aspects of the Biology of a Predaceous Anthomyiid Fly, \u3ci\u3eCoenosia Tigrina\u3c/i\u3e

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    The results of a two-year study in Michigan on the incidence of Coenosia tigrina adults under different onion production practices is presented. In Michigan, C. tigrina has three generations and is more abundant in organic agroecosystems than chemically-intensive onion production systems

    Galaxy Peculiar Velocities and Infall onto Groups

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    We perform statistical analyses to study the infall of galaxies onto groups and clusters in the nearby Universe. The study is based on the UZC and SSRS2 group catalogs and peculiar velocity samples. We find a clear signature of infall of galaxies onto groups over a wide range of scales 5 h^{-1} Mpc<r<30 h^{-1} Mpc, with an infall amplitude on the order of a few hundred kilometers per second. We obtain a significant increase in the infall amplitude with group virial mass (M_{V}) and luminosity of group member galaxies (L_{g}). Groups with M_{V}<10^{13} M_{\odot} show infall velocities V_{infall} \simeq 150 km s^{-1} whereas for M_{V}>10^{13} M_{\odot} a larger infall is observed, V_{infall} \simeq 200 km s^{-1}. Similarly, we find that galaxies surrounding groups with L_{g}<10^{15} L_{\odot} have V_{infall} \simeq 100 km s^{-1}, whereas for L_{g}>10^{15} L_{\odot} groups, the amplitude of the galaxy infall can be as large as V_{infall} \simeq 250 km s^{-1}. The observational results are compared with the results obtained from mock group and galaxy samples constructed from numerical simulations, which include galaxy formation through semianalytical models. We obtain a general agreement between the results from the mock catalogs and the observations. The infall of galaxies onto groups is suitably reproduced in the simulations and, as in the observations, larger virial mass and luminosity groups exhibit the largest galaxy infall amplitudes. We derive estimates of the integrated mass overdensities associated with groups by applying linear theory to the infall velocities after correcting for the effects of distance uncertainties obtained using the mock catalogs. The resulting overdensities are consistent with a power law with \delta \sim 1 at r \sim 10 h^{-1}Mpc.Comment: 25 pages, 10 figure

    Determining the Attitudes & Use of Complementary and Alternative Medicine (CAM) Among Collegiate Athletes

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    There are many different approaches to medicine, so it is necessary to expand current knowledge on what patients and clinicians are using. Efforts to expand complementary and alternative medicine (CAM) research will enhance clinicians’ perspectives by not only creating an interest in becoming educated on the topic, but also by challenging negative perspectives to become more unbiased. Clinicians should educate themselves and patients in a way that is non-discriminatory. PURPOSE: The purpose of this study is to gain insight on what medicinal practices collegiate-level athletes are utilizing in effort to heal themselves, whether that be physically, mentally, or spiritually. METHODS: A Qualtrics survey was sent via email to collegiate-level athletes in Texas. All division colleges are welcome to participate. There was a brief explanation in every email describing the purpose of the study and a concise definition of CAM. The data from the survey was reported based on the specified demographics including biological sex, ethnicity, sport played, number of years playing, eligibility classification, and attending college rank. The data was analyzed using mean, median, and mode for all individual questions. An independent samples t-test was utilized to analyze the variance of responses based upon demographic information. RESULTS: 41 completed survey responses were recorded with 78% of participants attending a NCAA Division 1 college. 78% of all participants also stated that they had sustained a sports-related injury with 90% stating that an athletic trainer or team physician treated the injury. 39% of participating athletes stated that healthcare personnel suggested CAM to them and 32% were unsure. According to the data analysis ascertained by an independent samples t-test, there was statistical significance between biological sex and if the participant had taken part in CAM, as demonstrated by p=0.55. 32% of athletes said they had taken part in CAM with 64% of total respondents reporting they were comfortable incorporating this avenue into their treatments. Participants’ agreeance when compared to ethnicity was noted to be statistically insignificant as demonstrated by p=0.25 on an independent samples t-test. CONCLUSION: According to the statistical analysis, there is limited significance between biological sex or ethnicity in accordance with how answer choices were selected. There was not enough variable data from participants to compare responses regarding sport played, number of years playing, college attended, or eligibility classification. Future research can be conducted to ascertain the involvement of CAM in collegiate athletes care and the impact regarding patient reported outcomes

    Constraint-Induced aphasia therapy: Three single case studies.

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    TITLE OF POSTER: CONSTRAINT INDUCED APHASIA THERAPY - THREE SINGLE CASE STUDIES INTRODUCTION This research project was inspired by the Specific Interest Group in Aphasia study day given by Professor Pulvermuller in January 2011. Constraint Induced Aphasia Therapy (CIAT) is sometimes referred to as Intensive Language Action Therapy (ILAT). This technique has an impressive research base to support its use for people with aphasia (PWA) and the evidence base includes both single case and randomised control trial evidence (Pulvermuller, Neininger, Elbert, Mohr, Rockstroh, Koebbl & Taub, 2001). Pulvermuller et al (2001) describe CIAT as a game of pairs. The game is normally played by four players: a therapist and three PWA. A 32 pack of cards consisting of 16 pairs is shuffled and divided equally between the four players. No one can see anyone else’s cards. The aim of the game is to win the most pairs of cards. Clients can win a pair by asking each of the other players in turn, for a matching card. All requests and responses should be verbal but participants may describe the target word or use a gesture in order to achieve saying the word. An essential part of the game is that each player should see and hear the name of the card in play. RESEARCH METHOD Three PWA were prioritised from a typical general hospital SLT caseload. All three clients were one to two years post onset of their aphasia and had already been provided with impairment focussed, functional and psychosocial SLT input. They had moderate to severe aphasia, had difficulties at several levels of single word processing and frequently failed to convey their message despite having a degree of linguistic competence and an ability to use alternative communication strategies. Accessible formal assessment measures (Kaplan, Goodglass & Weintraub 1983, Goodglass, Kaplan & Barresi 2000 & Swinburn, Porter & Howard 2004) were used to evaluate the success of therapy in a four step repeated measures research design: Baseline 1, 30 hours CIAT therapy, Baseline 2, Baseline 3. SUMMARY OF RESULTS For 2/3 clients, assessment results suggested that participation in the CIAT programme resulted in a positive measurable change in language behaviour. This positive change was not apparent in assessments of understanding. Selective improvement of language ability suggests that the therapy directed at language output had resulted in improved word and sentence level skills for 2/3 of our clients. There were also positive changes that were not captured by the assessment data: reduced use of written and therapist cues, improved repetition skills, improved self-monitoring and a reduced tendency to produce jargon type utterances. Relatives corroborated therapist perceptions. CONCLUSIONS In 2006 Beeson & Robey (2006, p162) proposed that rehabilitation outcome research should be conducted in five phases. Our study is one of the first to provide evidence to support the use of intensive CIAT therapy in the community (phase 4 – an effectiveness study). Other studies have assessed the usefulness of the therapeutic effect of ILAT (phase 1), optimised the ILAT procedure (phase 2) and tested its usefulness under ideal conditions (phase 3). The final phase outlined by Beeson & Robey (2006) is the cost-benefit analysis (phase 5) and we would welcome debate within the profession on improving this type of input and the role of Speech and Language Therapists in intensive aphasia therapy provision. REFERENCES Pulvermuller, F., Neininger, B., Elbert, T., Mohr, B., Rockstroh, B., Koebbl,P. & Taub, E. (2001) Constraint induced therapy for chronic aphasia after stroke. Stroke, 1621-1626. Beeson, P. M. & Robey, R.R. (2006) Evaluating single-subject treatment research: Lessons learnt from the aphasia literature. Neuropsychological Review, 16, 161-169. KAPLAN, E., GOODGLASS, H. and WEINTRAUB, S. (1983) The Boston Naming Test. Philadelphia: Lea and Febiger. Goodglass, H., Kaplan, E. & Barresi, B. (2000) Boston Diagnostic Aphasia Examination. 3rd Edition. San Antonio: Pearson. Swinburn, K., Porter, G., & Howard, D. (2004). The Comprehensive Aphasia Test. Hove: Psychology Press

    Tracking advanced persistent threats in critical infrastructures through opinion dynamics

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    Advanced persistent threats pose a serious issue for modern industrial environments, due to their targeted and complex attack vectors that are difficult to detect. This is especially severe in critical infrastructures that are accelerating the integration of IT technologies. It is then essential to further develop effective monitoring and response systems that ensure the continuity of business to face the arising set of cyber-security threats. In this paper, we study the practical applicability of a novel technique based on opinion dynamics, that permits to trace the attack throughout all its stages along the network by correlating different anomalies measured over time, thereby taking the persistence of threats and the criticality of resources into consideration. The resulting information is of essential importance to monitor the overall health of the control system and cor- respondingly deploy accurate response procedures. Advanced Persistent Threat Detection Traceability Opinion Dynamics.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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