scholarly journals Global and local interference effects in ensemble encoding are best explained by interactions between summary representations of the mean and the range

2021 ◽  
Author(s):  
Marco A. Sama ◽  
Dilakshan Srikanthan ◽  
Adrian Nestor ◽  
Jonathan S. Cant
Keyword(s):  
Local Level ◽  
Interference Effects ◽  
Single Item ◽  
Ensemble Perception ◽  
Item Level ◽  
The Mean ◽  
Ensemble Encoding ◽  
Average Size ◽  
Local Interference ◽  
Global And Local

AbstractThrough ensemble encoding, the visual system compresses redundant statistical properties from multiple items into a single summary metric (e.g., average size). Numerous studies have shown that global summary information is extracted quickly, does not require access to single-item representations, and often interferes with reports of single items from the set. Yet a thorough understanding of ensemble processing would benefit from a more extensive investigation at the local level. Thus, the purpose of this study was to provide a more critical inspection of global-local processing in ensemble perception. Taking inspiration from Navon (Cognitive Psychology, 9(3), 353-383, 1977), we employed a novel paradigm that independently manipulates the degree of interference at the global (mean) or local (single item) level of the ensemble. Initial results were consistent with reciprocal interference between global and local ensemble processing. However, further testing revealed that local interference effects were better explained by interference from another summary statistic, the range of the set. Furthermore, participants were unable to disambiguate single items from the ensemble display from other items that were within the ensemble range but, critically, were not actually present in the ensemble. Thus, it appears that local item values are likely inferred based on their relationship to higher-order summary statistics such as the range and the mean. These results conflict with claims that local information is captured alongside global information in summary representations. In such studies, successful identification of set members was not compared with misidentification of items within the range, but which were nevertheless not presented within the set.

Resource access mechanisms in networks and SME survival in Ghana

2018 ◽  
Vol 12 (5) ◽  
pp. 611-631 ◽  
Author(s):  
George Acheampong ◽  
Raphael Odoom ◽  
Thomas Anning-Dorson ◽  
Patrick Amfo Anim
Keyword(s):  
Census Data ◽  
Local Level ◽  
Directed Network ◽  
Resource Access ◽  
Content Type ◽  
Structural Hole ◽  
One Year ◽  
Global And Local ◽  
Access Mechanisms ◽  
Global Influence

Purpose The study aims to determine the resource access mechanism in inter-firm networks that aids SME survival in Ghana. Design/methodology/approach The authors collect census data on a poultry cluster in Ghana and construct a directed network. The network is used to extract direct and indirect ties both incoming and outgoing, as well as estimate the structural holes of the actors. These variables are used to estimate for survival of SMEs after a one-year period using a binary logit model. Findings The study finds that out-indirect ties and structural hole have a significant influence on SME survival. This works through the global influence and the vision advantage that these positions and ties offer the SMEs. Originality/value The study offers SMEs a choice of whom to collaborate with for information (resources) in the form of outgoing and incoming ties at both the global and local level.

scholarly journals Surgical and Postoperative Evaluations of Rectal Adenomas Ecised With a Novel Proctoscope.

2020 ◽  
Author(s):  
Roberta Denise Alkmin Lopes Lima ◽  
Rogerio Serafim Parra ◽  
Marley Ribeiro Feitosa ◽  
Omar Féres ◽  
José Joaquim Ribeiro Rocha
Keyword(s):  
Operative Time ◽  
Average Distance ◽  
Economic Feasibility ◽  
Surgeon Experience ◽  
Average Operative Time ◽  
The Mean ◽  
Average Size ◽  
High Level ◽  
Complex Methods

Abstract Purpose Many transanal endoscopic surgeries require a high level of technical expertise and surgeon experience. Considering the economic feasibility of material acquisition and the technical feasibility of training and experience with complex methods, a simpler technique with available resources is relevant for the excision of rectal adenomas. This study presents the surgical and postoperative results achieved with a novel proctoscope using the transanal endoscopic technique to excise rectal adenomas. The results are compared to the results obtained with other currently employed transanal techniques. Methods We retrospectively investigated the medical records of patients who underwent transanal endoscopic operations from April 2000 to June 2018 at two tertiary referral centers for colorectal cancer. Results This study included 99 patients. The mean age was 65.3 ± 13.3 years. The average size of the adenomas was 4.6 ± 2.3 cm, and their average distance to the anal border was 5.6 ± 3.3 cm. The average operative time was 65.3 ± 41.7 min. In 48.5% of the operations, the specimen was fragmented, and in 59.6% of the cases, the microscopic margins were free. The rates of postoperative complications and relapse were 5% and 19%, respectively. The mean follow-up was 80 ± 61.5 months. Conclusions The described proctoscope proved to be a viable technique with results similar to other techniques, with the advantage that it allowed greater accessibility for surgeons. Therefore, its use could be implemented and become widespread in surgical practice.

scholarly journals Effect of Long-Term Creep on Microstructure of a 9% Cr Heat Resistant Steel

2014 ◽  
Vol 783-786 ◽  
pp. 1839-1844
Author(s):  
Valeriy Dudko ◽  
Alexandra Fedoseeva ◽  
Pavel Kozlov ◽  
Vladimir Skorobogatykh ◽  
Izabella Schenkova ◽  
...  
Keyword(s):  
Prior Austenite ◽  
Average Thickness ◽  
Resistant Steel ◽  
Secondary Phases ◽  
Heat Resistant Steel ◽  
Gauge Section ◽  
The Mean ◽  
Average Size ◽  
Term Creep

The effect of long-term creep at 600°C under 137 MPa on the microstructure of a P92-type steel was investigated. The microstructure after tempering consisted of laths with an average thickness of 400 nm. Dispersion of secondary phases consists of M23C6carbides with an average size of 85 nm located mainly on lath, block and prior austenite boundaries and MX carbonitrides with average size of 31 nm homogeniously distributed throughout. Creep with duration of 40738 hours led to coarsening of M23C6carbides up to 182 nm. Precipitation of Laves phase with an average size of 290 nm took place in both grip and gauge portions of ruptured specimen. Vanadium-rich MX particles were replaced by particles of Z-phase with sizes of 97 and 48 nm after long-term creep and aging, respectively. The average misorientation of the lath boundaries was approximately 2° and scarcely varied during creep, while the mean lath thickness increased to 890 nm in gauge section of ruptured specimen and remained essentially unchanged in the grip section. Dislocation density decreased slightly under long-range aging and creep.

Challenges of medical residency. Are they perceived and addressed differently by international medical graduates, Canadian medical graduates, and preceptors?

2020 ◽  
Author(s):  
Neda Abedi ◽  
Michelle McCarren ◽  
Farzaneh Sheidaei ◽  
Andriyka L. Papish
Keyword(s):  
English Language ◽  
Multivariate Analyses ◽  
International Medical ◽  
International Medical Graduates ◽  
Residency Programs ◽  
Program Coordinators ◽  
Medical Graduates ◽  
Item Level ◽  
Scale Scores ◽  
The Mean

Abstract Background: Residency is an important and challenging part of medical education. Some of these challenges are common to all residents and some are specific to a particular group of residents. A number of studies have addressed the challenges of residency. To our knowledge, the experience of challenges from the perspective of international medical graduates (IMGs), Canadian medical graduates (CMGs), and their preceptors has not been studied in a single residency cohort. This study represents a valuable step in addressing the differential needs of international and Canadian medical graduates and in identifying the way different groups of residents can support each other to function better during residency.Methods: We surveyed residents and preceptors to determine what they perceive to be the greatest challenges for each group during residency. The survey was sent to the program coordinators of all English language psychiatry residency programs in Canada to be distributed to all residents and preceptors. Three reminders were sent, and a prize draw was offered to participants. Mean scale scores were calculated. One-way analyses of variance (ANOVAs) were calculated to compare resident self-ratings between groups, preceptors' ratings of each resident group's challenges, and all four groups' perceptions of the challenges experienced by different groups. To determine the particular types of challenges that residents experience, multivariate analyses of variance (MANOVAs) were also used for item-level comparisons.Results: 177 residents and 82 preceptors completed the survey. We found no significant differences in the mean scale scores for how each group rated their own challenges though the most challenging area was different for each group of residents. Preceptors viewed FIMGs as experiencing the greatest challenges (M = 3.27, SD = 0.066, 95% CI [3.11, 3.41]) and CMGs, the least (M = 2.02, SD = 0.59, 95% CI [1.89, 2.16]; F (2, 227) = 88.030, p < 0.001).Conclusion: Although the degree of challenge perceived by all groups of residents was relatively similar in general, different groups of residents identified different areas of challenges from their own perspective, and these areas differed from those identified by their resident colleagues and preceptors as being challenging for each group. This study highlights the necessity for reviewing the needs, strengths, and challenges of each group of residents and the importance of better communication between preceptors and residents regarding the different areas of challenges.

scholarly journals The Validity of Functional Threshold Power and Maximal Oxygen Uptake for Cycling Performance in Moderately Trained Cyclists

Sports ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 217 ◽  
Author(s):  
Arne Sørensen ◽  
Tore Kristian Aune ◽  
Vegar Rangul ◽  
Terje Dalen
Keyword(s):  
Oxygen Uptake ◽  
Maximal Oxygen Uptake ◽  
Local Level ◽  
Cycling Performance ◽  
Threshold Power ◽  
Mountain Bike ◽  
Mean Power ◽  
Valid Test ◽  
The Mean ◽  
And Performance

Cycling is a popular sport, and evaluation of the validity of tests to predict performance in competitions is important for athletes and coaches. Similarity between performance in sprints in mass-start bike races and in the laboratory is found, but, to our knowledge, no studies have investigated the relationship between laboratory measurements of maximal oxygen uptake (VO2max) and functional threshold power (FTP) with performance in official mass-start competitions. The purpose of this study was to evaluate the validity of a 20 min FTP test and VO2max as predictors for performance in an official mountain bike competition. Eleven moderately trained male cyclists at a local level participated in this study (age: 43 ± 5.1 years; height: 183.4 ± 5.4 m; weight: 84.4 ± 8.7 kg; body mass index: 25.1 ± 2.1). All subjects performed a 20 min FTP test in the laboratory to measure the mean power. In addition, the subjects completed an incremental test to exhaustion to determine VO2max. These two laboratory tests were analyzed together with the results from a 47 km mass-start mountain bike race, with a total elevation of 851 m. A significant relationship was found between the mean relative power (W/kg) for the 20 min FTP test and performance time in the race (r = −0.74, P < 0.01). No significant correlation was found between VO2max and cycling performance for these subjects (r = −0.37). These findings indicate that a 20 min FTP test is a more valid test for prediction of performance in mass-start bike races than a VO2max test for moderately trained cyclists.

scholarly journals Effect of Trace Yttrium Addition and Heat Treatment on the Microstructure and Mechanical Properties of As-Cast ADC12 Aluminum Alloy

2018 ◽  
Vol 9 (1) ◽  
pp. 53 ◽  
Author(s):  
Jianlong Liu ◽  
Qingjie Wu ◽  
Hong Yan ◽  
Songgen Zhong ◽  
Zhixiang Huang
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aluminum Alloy ◽  
Primary Si ◽  
Microstructure And Mechanical Properties ◽  
Yttrium Addition ◽  
The Matrix ◽  
The Mean ◽  
Average Size ◽  
Small Average Size

The effects of rare earth yttrium (Y) additions and the heat treatment process on the microstructure and mechanical properties of as-cast ADC12 aluminum alloy have been investigated. The results showed that the primary Si crystals were significantly refined from long axis to fibrous or granular when the Y content was 0.2 wt%. Compared to the matrix, the mean area and aspect ratio were decreased by 92% and 75%, respectively. Moreover, the Si and Fe-rich phases were spheroidized and refined with a small average size during the solid solution. It was also noted that the copper-rich phases were dissolved into the matrix. Correspondingly, it was found that after metamorphic and heat treatment the ultimate tensile strength (UTS), elongation, and, hardness increased by 81.9%, 69.7%, and 74.8%, respectively, compared to the matrix. The improved mechanical properties can primarily be attributed to the optimization of the microstructure and the refinement of various phases.

Processing of global and local information in memory

1989 ◽  
Vol 41 (1) ◽  
pp. 167-181 ◽  
Author(s):  
Rino Rumiati ◽  
Roberto Nicoletti ◽  
Remo Job
Keyword(s):  
Local Level ◽  
Memory System ◽  
Local Information ◽  
Global Information ◽  
Global Level ◽  
Capital Letter ◽  
Global And Local

The experiments reported in this paper were designed to test how global and local information are processed by the memory system. When subjects are required to match a given letter with either a previously presented large capital letter or the small capital letters comprising it, (1) responses to the global level (i.e. the big letter) are faster than responses to the local level (i.e. the small letters), and (2) responses to the latter level only are affected by the consistency between the large and the small letters (Experiment 2), a pattern similar to that obtained in perception (Experiment 1). Such results obtain when subjects are required to attend to only one level with a short ISI between the first and second stimulus, but not when a longer ISI is used (Experiment 5) or when subjects are required to attend to both levels at the same time (Experiments 3 and 4). The results are discussed in the light of a model that postulates a temporal precedence of the global information over the local one at the perceptual level.

scholarly journals Assessing bilingual dominance

2002 ◽  
Vol 23 (4) ◽  
pp. 567-598 ◽  
Author(s):  
JAMES EMIL FLEGE ◽  
IAN R. A. MACKAY ◽  
THORSTEN PISKE
Keyword(s):  
First Language ◽  
Poor Performance ◽  
The Self ◽  
Original Sample ◽  
Interference Effects ◽  
Self Rating ◽  
Foreign Accents ◽  
The Mean ◽  
L1 Use ◽  
High Level

This study used two methods to assess bilingual dominance in four groups of 18 Italian–English bilinguals, who were selected on the basis of age of arrival (AOA) in Canada (early: 2–13 years; late: 15–26 years) and percentage use of the first language (L1), Italian (low L1 use: 1–15%; high L1 use: 25–85%). Ratios were derived from the bilinguals' self-ratings of ability to speak and understand Italian compared to English (the “verbal” self-rating ratios) and to read and write Italian compared to English (the “written” self-rating ratios). The ratio of the mean duration of English and Italian sentences produced by each bilingual was also computed. AOA and L1 use had the same effect on the self-rating and sentence duration ratios, which were correlated. The bilinguals who arrived in Canada as young adults and continued to use Italian often were the most likely to be Italian dominant. Dominance in Italian was associated with a relatively high level of performance in Italian (assessed in a translation task) and relatively poor performance in English (assessed by measuring strength of foreign accents). Both groups of late bilinguals (late low, late high) and both groups of early bilinguals (early low, early high) were found to produce English sentences with detectable accents. However, a group of 18 bilinguals (all early bilinguals) selected from the original sample of 72 based on their dominance in English did not have detectable foreign accents. This suggested that interlingual interference effects may not be inevitable.

scholarly journals Iterated index and the mean Euler characteristic

2015 ◽  
Vol 07 (03) ◽  
pp. 453-481 ◽  
Author(s):  
Viktor L. Ginzburg ◽  
Yusuf Gören
Keyword(s):  
Euler Characteristic ◽  
Contact Manifold ◽  
Finsler Metric ◽  
Topological Invariants ◽  
Closed Geodesics ◽  
Lefschetz Numbers ◽  
Local Case ◽  
The Mean ◽  
Standard Contact ◽  
Global And Local

The aim of the paper is three-fold. We begin by proving a formula, both global and local versions, relating the number of periodic orbits of an iterated map and the Lefschetz numbers, or indices in the local case, of its iterations. This formula is then used to express the mean Euler characteristic (MEC) of a contact manifold in terms of local, purely topological, invariants of closed Reeb orbits, without any non-degeneracy assumption on the orbits. Finally, turning to applications of the local MEC formula to dynamics, we use it to reprove a theorem asserting the existence of at least two closed Reeb orbits on the standard contact S3 (by Cristofaro–Gardiner and Hutchings in the most general form) and the existence of at least two closed geodesics for a Finsler metric on S2 (Bangert and Long).

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