196,419 research outputs found
Hands as tools: how manual behavior shapes actions and spontaneous and task-evoked brain activity
No full textHumans establish interactions with external objects through stereotypical upper-limb movements. These regularities may generate probabilistic representations about the body and internal models (i.e., prior) for adaptive sensorimotor control. Recent studies show that, in the absence of any task, spontaneous brain activity patterns resemble those evoked by the execution of ecological hand movements. These observations suggest that, even at rest, the brain preserves a hand representation, likely for efficient motor control. Through hands, humans manipulate tools that can be incorporated into the body schema (i.e., brain representation of the body).
Using neuroimaging studies, we tested whether spontaneous activity patterns more strongly resemble patterns evoked by the observation of visual stimuli depicting hands vs non-hands and regular vs perturbed object-related arm and hand movements. Then, in two behavioral studies, we explored whether humans could embody a bionic tool (i.e., experience it as part of the body) and thus if this would affect behavior and the body schema. Results showed that spontaneous activity patterns code for the visual representation of human hands in somatomotor brain regions and for regular upper-limb movements in the dorsal attention network. Furthermore, we found that the virtual grafting of a bionic tool elicits a sense of embodiment like or even stronger than its natural counterpart (i.e., a virtual hand) and that tool use can alter the body representation through changes in muscular intensity and kinematics parameters.
We suggest that hand shape and regular movements are more represented in spontaneous activity than control stimuli, likely due to replay mechanisms for processing and interpreting information to which we are regularly exposed. Our studies also indicate that the natural use of bionic tools can change human behavior, opening new research and application possibilities, especially for amputees struggling to embody prosthetic limbs
High performance wobbling subreflector for the MITO 2.6-m telescope
No full textThe Millimetre and Infrared Testa Grigia Observatory 2.6-m Cassegrain telescope has been designed to allow high-sensitivity observations in the millimeter spectral range. For this purpose, in order to reduce unwanted contributions from local foregrounds, we adopted a sky-chopping technique, by wobbling the telescope subreflector. We describe the design and performance of the wobbling system, which can endure external forced two and three fields square-wave modulation and includes features such as high frequency, high amplitude, high duty cycle, low microphonics, and high stability. © 1996 Optical Society of America
A vertical accelerometer for cryogenics implementation in third-generation gravitational-wave detectors
No full textThe design of third-generation gravitational-wave detectors requires dedicated sensors to perform very accurate measurements of the residual motion of mechanical components cooled down at cryogenic temperatures and accommodated close to the test masses. For this reason, we developed a vertical accelerometer prototype derived by the classical scheme widely used in Virgo seismic suspension control. Thermal contractions are the main concern when cooling down such a device and the calibration check at low temperature, in the absence of commercial sensors working in parallel, plays a crucial role. The accelerometer was conceived to be used at low frequencies (0.3–3 Hz) in a quite specific environment, where the noise produced by cryocoolers has to be suppressed. However, it can be easily operated over a wider frequency band, up to ~100 Hz. The achieved sensitivity is ~10−8 m s−2 below 3 Hz. During 2013, the device was successfully installed in the KAGRA cryostat, where it was tested at low temperatures down to 8 K and provided the measurement of vertical vibrational modes of the inner thermal shield
Noninvasive electrocardiographic parameters to assess interventricular dyssynchrony in dogs with bundle branch blocks
No full textObjectives: To define electrocardiographic features of complete left bundle branch block (LBBB) and right bundle branch block (RBBB), and the use of R-peak time (RPT) to identify interventricular dyssynchrony in dogs with BBB.
Animals, materials and methods: Twelve-lead ECG tracings of 20 dogs with RBBB, 20 with LBBB, and 60 healthy dogs were retrospectively analyzed and RPT was measured in precordial leads. Interventricular dyssynchrony index (IDI) was than calculated.
Results: In RBBB, mean electrical axis (MEA) was 111 [120/100], V1RPTwas significantly longer (61 ms [55e72 ms]) than left precordial leads RPT (V2:25 ms [22e30 ms]; V3:25 ms [22e29 ms]; V4:24 ms [21e29 ms]; V5:25 ms [22e29 ms]; V6:25 ms [22e29 ms]) and when compared to normal dogs (P < 0.001). In LBBB, MEA was 76 [70/81], RPT in left precordial leads was significantly longer (V2:49 ms [34e58 ms]; V3:49 ms [43e57 ms]; V4:52 ms [45e62 ms]; V5:53 ms [45e63 ms]; V6:55 ms [45e63 ms]) than V1RPT (17 ms [15e20 ms]) and when compared to normaldogs (P<0.001). V1RPT>28 ms and V5RPT>36 ms were found to predict the presence of RBBB and LBBB with a sensitivity of 100% and 96.7%, and a specificity of 96.7% and 99.5%, respectively. The IDI was 23% [16e29%] in normal dogs and significantly greater in dogs with RBBB (33% [30e38%]; P < 0.001) and LBBB (32% [23e41%]; P 1⁄4 0.006).
Conclusions: This study defines ECG features and RPT in dogs with BBB. Electrical interventricular dyssynchrony can be defined using IDI in dogs with BBB
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Cannabinoids in glaucoma patients: The never-ending story
No full textGlaucoma is one of the principal causes of irreversible blindness worldwide. Yet, intraocular pressure (IOP) is the main modifiable risk factor for disease progression. In the never-ending challenge to develop new and effective drugs, several molecules have been tested as anti-glaucoma agents thanks to their pressure-lowering capabilities. Among these molecules, the cannabinoids have been investigated as possible anti-glaucoma drugs since the early 1970s. Cannabinoids are a large class of chemical compounds that exploit their effects by interaction with cannabinoid receptors 1 and 2. These receptors are widely expressed in the human retina where they may influence important functions such as photo-transduction, amacrine cell network maintenance, and IOP regulation. Therefore, in past years several studies have been conducted in order to assess the IOP lowering effects of cannabinoids. PRISMA guidelines have been used to perform a literature search on Pubmed and Scopus aiming to investigate the mechanism of IOP lowering effects and the potential benefits of orally administered, inhaled, topical, and intravenous cannabinoids in the treatment of glaucoma patients
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
- …
