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Koizumi Hiroyasu Morio Naoki Ishikawa Alto Kondo Takumi 《Journal of Superconductivity and Novel Magnetism》2022,35(9):2357-2370
Journal of Superconductivity and Novel Magnetism - We theoretically study the superconductivity in hole-doped cuprate superconductors by employing a model composed of surface and bulk CuO $$_2$$... 相似文献
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Hilary Alto Rangaraj M. Rangayyan Raman B. Paranjape J. E. Leo Desautels Heather Bryant 《电信纪事》2003,58(5-6):820-835
Computer-aided diagnosis (cad) systems are being developed to assist radiologists in the interpretation of ambiguous mammographic features corresponding to possible signs of early breast cancer. Databases of digital mammograms are needed for testing such systems; we present an overview of a few such databases. Most databases are limited to single-exam sets of two or four mammograms on which the diagnosis was made, some ground-truth information related to the position of diagnostically significant mammographic features, and the diagnosis. We propose the design of a comprehensive, indexed atlas of digital mammograms. The design of an appropriate indexing scheme facilitates the implementation of content-based retrieval techniques needed for efficient access to and retrieval of relevant cases from the atlas. We also propose the use of mobile software agents for facilitating remote consultation of the atlas. Mobile agents can move between data sources such as the atlas and hospital repositories, perform computational tasks at each site, and return only relevant data to the user. These features reduce the computational requirements of the local computer system, bandwidth requirements, and overall network traffic. Proposed applications of the atlas include research, remote consultation, teaching, evaluation ofcad systems, and self-evaluation by radiologists. 相似文献
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Sergios Gatidis Hansjörg Graf Jakob Weiß Alto Stemmer Berthold Kiefer Konstantin Nikolaou Mike Notohamiprodjo Petros Martirosian 《Magma (New York, N.Y.)》2017,30(1):57-63
Objective
Our objective was to compare available techniques reducing artifacts in echo planar imaging (EPI)-based diffusion-weighed magnetic resonance imaging MRI (DWI) of the neck at 3 Tesla caused by B0-field inhomogeneities.Materials and methods
A cylindrical fat–water phantom was equipped with a Maxwell coil allowing for additional linear B0-field variations in z-direction. The effect of increasing strength of this superimposed gradient on image quality was observed using a standard single-shot EPI-based DWI sequence (sEPI), a zoomed single-shot EPI sequence (zEPI), a readout-segmented EPI sequence (rsEPI), and an sEPI sequence with integrated dynamic shimming (intEPI) on a 3-Tesla system. Additionally, ten volunteers were examined over the neck region using these techniques. Image quality was assessed by two radiologists. Scan durations were recorded.Results
With increasing strength of the external gradient, marked distortions, signal loss, and failure of fat suppression were observed using sEPI, zEPI, and rsEPI. These artifacts were markedly reduced using intEPI. Significantly better in vivo image quality was also observed using intEPI compared with the other techniques. Scan time of intEPI was similar to sEPI and zEPI and shorter than rsEPI.Conclusion
The use of integrated 2D shim and frequency adjustment for EPI-based DWI results in a significant improvement in image quality of the head/neck region at 3 Tesla. Combining integrated shimming with rsEPI or zEPI can be expected to provide additional improvements.4.
Chichak KS Star A Altoé MV Stoddart JF 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(4):452-461
A dynamic coordinative-directed solubilization of single-walled carbon nanotubes (SWNTs) in aqueous solutions has been achieved through a combination of a Zn(II) metalloporphyrin complex and a cis-protected Pd(II) complex, which are believed to form charged acyclic and/or cyclic adducts on or around the side walls of SWNTs. The solubilization of SWNTs in aqueous solution only occurs when these acyclic and/or cyclic complexes are allowed to enter simultaneously into a self-assembly process with SWNTs under mild conditions. The aqueous solubility properties that these dynamic complexes confer upon SWNTs are believed to involve noncovalent bonding interactions between the two entities. They have been probed in solution using ultraviolet and visible absorption spectroscopy and in thin films using high-resolution transmission electron microscopy. The supramolecular electronic effects that the individual components of their acyclic and/or cyclic complexes impart upon a single semiconducting SWNT have been probed within a nanotube field-effect transistor device. 相似文献
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The usefulness of diffusion‐weighted readout‐segmented EPI and fast spin echo with BLADE (PROPELLER) k‐space sampling: A comparison with single‐shot EPI for diffusion‐weighted imaging in ischemic stroke patients
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Jinhee Jang Kook‐Jin Ahn Bom‐Yi Kim David Porter Alto Stemmer Hyun Seok Choi So‐Lyung Jung Bum‐Soo Kim 《International journal of imaging systems and technology》2016,26(3):216-224
We evaluated the value of diffusion‐weighted readout‐segmented EPI (DW rs‐EPI) and diffusion‐weighted fast spin echo images with BLADE (PROPELLER) k‐space sampling (DW BLADE) in patients with ischemic stroke through intra‐individual comparisons with diffusion‐weighted single‐shot EPI (DW ss‐EPI). Forty‐four patients with acute ischemic stroke who had undergone three different types of diffusion weighted imaging (DWI) (b = 1000 s/mm2) were included. Two reviewers assessed the three types of DWI for diagnostic confidence based on a five‐point confidence score (CS). The inter‐ and intra‐observer agreements for the CS were assessed. The DWI signal ratio to the contralateral normal area and the apparent diffusion coefficient (ADC) of DWI lesions were compared. The CSs of the three DWI methods were significantly different (P < 0.001). A post hoc analysis showed a significantly higher CS with DW rs‐EPI than with DW ss‐EPI (P = 0.022). There were significant increases in the CSs for DW rs‐EPI compared to DW ss‐EPI, for patients who underwent DWI within 24 h of symptom onset, and for patients with DWI lesions ≤ 50 mm2. The inter‐observer and intra‐observer agreements of the CS were good. DW rs‐EPI increased the diagnostic confidence of ischemic stroke compared to DW ss‐EPI, particularly for patients with small lesions and for those who underwent DWI within 24 h of symptom onset. DW BLADE showed a similar level of diagnostic confidence to DW ss‐EPI. © 2016 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 26, 216–224, 2016 相似文献
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Scrimin Sara; Moscardino Ughetta; Capello Fabia; Altoè Gianmarco; Axia Giovanna 《Canadian Metallurgical Quarterly》2009,45(5):1341
This exploratory study aims at investigating the effects of terrorism on children’s ability to recognize emotions. A sample of 101 exposed and 102 nonexposed children (mean age = 11 years), balanced for age and gender, were assessed 20 months after a terrorist attack in Beslan, Russia. Two trials controlled for children’s ability to match a facial emotional stimulus with an emotional label and their ability to match an emotional label with an emotional context. The experimental trial evaluated the relation between exposure to terrorism and children’s free labeling of mixed emotion facial stimuli created by morphing between 2 prototypical emotions. Repeated measures analyses of covariance revealed that exposed children correctly recognized pure emotions. Four log-linear models were performed to explore the association between exposure group and category of answer given in response to different mixed emotion facial stimuli. Model parameters indicated that, compared with nonexposed children, exposed children (a) labeled facial expressions containing anger and sadness significantly more often than expected as anger, and (b) produced fewer correct answers in response to stimuli containing sadness as a target emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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NW Levin SL Parnell HN Prince F Gotch HD Polaschegg R Levin A Alto AM Kaufman 《Canadian Metallurgical Quarterly》1995,6(6):1578-1585
Dialyzer reprocessing with heated water (100 to 105 degrees C) for 20 h can be used safely in lieu of chemical methods for disinfection. All infective agents including spores are destroyed and depyrogenation may occur. However, these temperatures may result in structural damage to the dialyzer, limiting reuse. Dialyzer reprocessing by using 1.5% citric acid heated to 95 degrees C for 20 h is an alternative method that produces equivalent microbiologic effects. Citric acid is well known as a disinfecting agent used for dialysis equipment. Because there is little structural damage to dialyzer components at 95 degrees C, reuse statistics are improved (mean reuse increased to 12.8). Both small and large molecule clearances and the sieving coefficient for protein are insignificantly altered by the process. Whereas the procedure is relatively simple, quality-assurance indicators are essential. The method has appeal because it avoids the use of chemical germicides. However, at present it has only been tested thoroughly in polysulfone dialyzers with heat-resistant polycarbonate casings and polyurethane resin. The clinical experience is favorable. 相似文献
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Rachel Ward-Flanagan Alto S. Lo Elizabeth A. Clement Clayton T. Dickson 《International journal of molecular sciences》2022,23(7)
Anesthesia is a powerful tool in neuroscientific research, especially in sleep research where it has the experimental advantage of allowing surgical interventions that are ethically problematic in natural sleep. Yet, while it is well documented that different anesthetic agents produce a variety of brain states, and consequently have differential effects on a multitude of neurophysiological factors, these outcomes vary based on dosages, the animal species used, and the pharmacological mechanisms specific to each anesthetic agent. Thus, our aim was to conduct a controlled comparison of spontaneous electrophysiological dynamics at a surgical plane of anesthesia under six common research anesthetics using a ubiquitous animal model, the Sprague-Dawley rat. From this direct comparison, we also evaluated which anesthetic agents may serve as pharmacological proxies for the electrophysiological features and dynamics of unconscious states such as sleep and coma. We found that at a surgical plane, pentobarbital, isoflurane and propofol all produced a continuous pattern of burst-suppression activity, which is a neurophysiological state characteristically observed during coma. In contrast, ketamine-xylazine produced synchronized, slow-oscillatory activity, similar to that observed during slow-wave sleep. Notably, both urethane and chloral hydrate produced the spontaneous, cyclical alternations between forebrain activation (REM-like) and deactivation (non-REM-like) that are similar to those observed during natural sleep. Thus, choice of anesthesia, in conjunction with continuous brain state monitoring, are critical considerations in order to avoid brain-state confounds when conducting neurophysiological experiments. 相似文献
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NW Levin PM Yang DA Hatch AJ Dubrow NS Caraiani TS Ing VC Gandhi A Alto SM Davila FR Prosl HD Polaschegg J Megerman 《Canadian Metallurgical Quarterly》1998,54(5):1739-1745
A new subcutaneous device (Dialock; Biolink Corp., Middleboro, MA) provides vascular access to patients who currently require hemodialysis (HD). The device consists of a port-like valve, implanted subcutaneously below the clavicle, which provides a linear flow passage to two catheters placed in the right atrium via the jugular vein. The valve is accessed percutaneously with needle-cannulas that functionally convert the device to twin catheters for connecting the patient to the HD lines. Interdialytic patency is maintained using a standard heparin lock. The device has been implanted in 10 outpatients under local anesthesia, with almost immediate use for HD (median, 3 days) and has functioned successfully for more than 6 months (mean +/- SD, 4.0 +/- 1.7; > 400 dialysis sessions). Blood flows over 300 ml/min were consistently achieved (average, 320 +/- 50) with venous and arterial pressures of 197 +/- 42 mmHg and -241 +/- 31 mmHg, respectively. After 40 patient-months, condition of the needle puncture sites remains satisfactory. Four systemic infections have occurred in three patients; all have resolved without the need for device removal. There have been no infections at the puncture sites. One patient whose heparin lock was not changed for 23 days (for reasons unrelated to the device) required fibrin sheath stripping of his catheters. Patient and nurse acceptance has been excellent. The device may offer substantial improvement over conventional devices for HD access. 相似文献
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