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11.
Before 12 months of age, infants have difficulties coordinating and sequencing their movements to retrieve an object concealed in a box. This study examined (a) whether young infants can discover effective retrieval solutions and consolidate movement coordination earlier if exposed regularly to such a task and (b) whether different environments, indexed by box transparency, would impact the rate of learning and time of discovery of these solutions. Infants (N=12) were presented with an object retrieval task every week from 6 1/2 months of age until they were able to retrieve the toy from the box using coordinated two-handed patterns for 3 weeks. To reach that criterion, infants tested with an opaque box took 2 1/2 months and infants tested with a semitransparent box took 1 1/2 months. Both groups outperformed age-matched controls who received a one-time exposure to the task. Repeated exposure to the task and vision of the toy significantly enhanced this process of solution discovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
This study compared the effects of estrogen (E) on the hyperactivity induced by (+)-3,4-methylenedioxymethamphetamine (MDMA) with E effects on cocaine-evoked hyperactivity in female rats. Sprague-Dawley rats were ovariectomized (OVX); half of them received a 17β-estradiol (E?) implant (OVX + E). Three weeks later, rats received saline, (+)-MDMA (1, 2, or 4 mg/kg) or cocaine (5, 10, or 20 mg/kg), and locomotor activity was monitored. OVX + E rats exhibited greater locomotor hyperactivity in response to both psychostimulants than did OVX rats. The enhanced response to cocaine appeared within 5 min following drug injection whereas the enhanced response to (+)-MDMA was delayed for approximately 30 min. The differential effects of E on hyperactivity may be due to the unique profiles of dopamine (DA) and serotonin (5-HT) in response to (+)-MDMA and cocaine. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
In 3 experiments, 9-month-old infants' expectations for what distinct count noun labels refer to were investigated. In Experiment 1, a box was opened to reveal 2 objects inside during familiarization: either 2 identical objects or 2 different objects. Test trials followed the same procedure, except before the box was opened, the contents were described using 2 distinct labels ("I see a wug! I see a dak!") or the same label twice ("I see a zav! I see a zav!"). Infants who heard a label repeated twice looked longer at 2 different objects versus 2 identical objects, whereas infants who heard 2 distinct labels showed a different pattern of looking. Experiments 2 and 3 presented infants with object pairs that only differed in shape or color, and it was found that infants expected the different-shaped (but not the different-colored) objects to be labeled by distinct count nouns. Because the property of shape is a cue to kind membership and the property of color is not, these results suggest that even at the beginning of word learning, infants may expect distinct labels to refer to distinct kinds of objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
Liza-Anastasia DiCecco Andrew D'Elia Chelsea Miller Prof. Dr. Kyla N. Sask Prof. Dr. Leyla Soleymani Prof. Dr. Kathryn Grandfield 《Chembiochem : a European journal of chemical biology》2021,22(15):2488-2506
For biological imaging using electron microscopy (EM), the use of room-temperature ionic liquids (RTILs) has been proposed as an alternative to traditional lengthy preparation methods. With their low vapor pressures and conductivity, RTILs can be applied onto hard-to-image soft and/or wet samples without dehydration – allowing for a more representative, hydrated state of material and opening the possibility for visualization of in situ physiological processes using conventional EM systems. However, RTILs have yet to be utilized to their full potential by microscopists and microbiologists alike. To this end, this review aims to provide a comprehensive summary of biological applications of RTILs for EM to bridge the RTIL, in situ microscopy, and biological communities. We outline future research avenues for the use of RTILs for the EM observation of biological samples, notably i) RTIL selection and optimization, ii) applications for live cell processes and iii) electron beam and ionic liquid interaction studies. 相似文献
15.
Avi Parush Chelsea Kramer Tara Foster-Hunt Alicia McMullan Kathryn Momtahan 《Cognition, Technology & Work》2014,16(1):47-57
Teamwork is prevalent in many work contexts. This study explored the similarities and differences in teamwork processes across different healthcare work contexts with the aim of assessing knowledge transfer feasibility. The research approach was to aggregate team communication analyses from four healthcare contexts to uncover teamwork similarities and differences. The four healthcare contexts included two handoffs and two surgery contexts. The communication analysis segmented communication into meaningful sequences. It categorized utterances into content categories and verbal behaviors. There were a few similar content categories across the four contexts. A clear information structure emerged in the two handoff contexts. In addition, there were more dialogues and requests in the surgeries compared to more reports in the handoffs. The content similarities suggest that some knowledge is transferable among the contexts. However, the differences in communication patterns reflect fundamental differences between handoff and surgery contexts in some teamwork processes. This research demonstrated that using communication analysis can uncover similarities and differences in team cognition and teamwork processes across work contexts. This in turn can help determine what knowledge and methods pertaining to team training, procedures, and technology are transferable across the contexts. 相似文献
16.
Programmers build large‐scale systems with multiple languages to leverage legacy code and languages best suited to their problems. For instance, the same program may use Java for ease of programming and C to interface with the operating system. These programs pose significant debugging challenges, because programmers need to understand and control code across languages, which often execute in different environments. Unfortunately, traditional multilingual debuggers require a single execution environment. This paper presents a novel composition approach to building portable mixed‐environment debuggers, in which an intermediate agent interposes on language transitions, controlling and reusing single‐environment debuggers. We implement debugger composition in Blink, a debugger for Java, C, and the Jeannie programming language. We show that Blink is (i) simple: it requires modest amounts of new code; (ii) portable: it supports multiple Java virtual machines, C compilers, operating systems, and component debuggers; and (iii) powerful: composition eases debugging, while supporting new mixed‐language expression evaluation and Java native interface bug diagnostics. To demonstrate the generality of interposition, we build prototypes and demonstrate debugger language transitions with C for five of six other languages (Caml, Common Lisp, C#, Perl 5, Python, and Ruby) without modifications to their debuggers. Using real‐world case studies, we show that diagnosing language interface errors require prior single‐environment debuggers to restart execution multiple times, whereas Blink directly diagnoses them with one execution. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
17.
Kathleen S. Hartzel Kathryn A. Marley William E. Spangler 《Journal of Computer Information Systems》2016,56(2):87-96
This research explores the extent to which users across cultures adopt the technology of online social networks (OSNs) in order to promote or support a social cause. By surveying graduate-level university students at institutions in the United States, China and India, this research builds on prior work in technology acceptance to model and explain how three elements of the task domain – the cultural aspects of the user, the social nature of the technology, and the social nature of the task – combine to influence the constructs and relationships within a modified Technology Acceptance Model (TAM) framework as well as the behavior that flows from it. This study contributes to our understanding of technology adoption by showing how OSNs are adopted by users across cultures in promoting and supporting social causes. 相似文献
18.
Applying a critical approach to investigate barriers to digital inclusion and online social networking among young people with disabilities
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Lareen Newman Kathryn Browne‐Yung Parimala Raghavendra Denise Wood Emma Grace 《Information Systems Journal》2017,27(5):559-588
Despite the seeming ubiquity of young people's Internet use, there are still many for whom access to the Internet and online social networking remains inequitable and patterned by disadvantage. The connection between information technology and young people with disabilities is particularly under‐researched. This article contributes to the field of critical information systems research by exposing significant barriers and facilitators to Internet accessibility for young people with disabilities. It uses Bourdieu's critical theory to explore how the unequal distribution of resources shapes processes of digital inclusion for young people with disabilities. It highlights access needs and experiences that are both disability and non‐disability related. The article draws on interviews in South Australia with 18 young people aged 10–18 years with a physical disability (such as cerebral palsy) or acquired brain injury and with 17 of their family members. Interviews evaluated participants' and parents' reflections on the benefits of a home‐based, goal‐oriented intervention to increase the young person's Internet use for social participation purposes. The Bourdieuian analysis demonstrated how varying levels of accrued individual and family offline capital resources are related to digital/online resources and disability‐specific online resources. This revealed how unequal resources of capital can influence technology use and hence digital inclusion for young people with disabilities. Our study demonstrates that young people with particular types of disabilities require intensive, personalised and long‐term support from within and beyond the family to ‘get online’. We conclude that Internet studies need to more frequently adopt critical approaches to investigate the needs of users and barriers to information technology use within sub‐groups, such as young people with disabilities. © 2016 John Wiley & Sons Ltd 相似文献
19.
Weaver Kathryn E.; Llabre María M.; Durán Ron E.; Antoni Michael H.; Ironson Gail; Penedo Frank J.; Schneiderman Neil 《Canadian Metallurgical Quarterly》2005,24(4):385
The authors tested a structural model that incorporated age, time since diagnosis, social support, coping, and negative mood as predictors of medication adherence and HIV viral load on 188 men and 134 women on highly active antiretroviral therapy (HAART). The authors used psychosocial latent factors formed from baseline measures to predict latent factors of adherence, as assessed by electronic monitoring and self-report, and viral load defined by indicators assessed over a 15-month period. Results from the model indicate that greater negative mood and lower social support are related to greater use of avoidance-oriented coping strategies. Use of these coping strategies by patients on HAART is related to poorer medication adherence and, subsequently, higher viral load. This model advances researchers' understanding of the contribution of psychosocial variables in predicting treatment adherence and disease progression in HIV-positive men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
Agonists acting at the serotonin-1B receptor (5-HT?BR) and 5-HT?CR have been reported to potentiate and block, respectively, the discriminative stimulus effects of cocaine. The present investigation reassessed the antagonistic effects of the mixed 5-HT?C/?BR agonist m-chlorophenylpiperazine (mCPP) on the discriminative stimulus effects of cocaine in the presence or absence of selective antagonism of the 5-HT?BR or 5-HT?CR. The stimulus effects of cocaine were attenuated by mCPP at doses that reduced response rates. The selective 5-HT?CR antagonist SB 242084, but not the selective 5-HT?BR antagonist GR 127935, reversed the mCPP-evoked attenuation of the cocaine cue and the suppression of response rates. These results demonstrate that the suppressive effects of mCPP on cocaine discrimination are related to stimulation of the HT?CR. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献