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1.
Kun?Guo Robert?G.?RobertsonEmail author Sasan?Mahmoodi Yoav?Tadmor Malcolm?P.?Young 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,150(3):363-374
Face perception plays a crucial role in primate social communication. We have investigated the pattern of eye movements produced
by rhesus monkeys (Macaca mulatta) as they viewed images of faces. Eye positions were recorded accurately using implanted eye coils, while neutral upright,
inverted and scrambled images of monkey and human faces were presented on a computer screen. The monkeys exhibited a similar
eye scan pattern while viewing familiar and unfamiliar monkey face images, or while viewing monkey and human face images.
No differences were observed in the distribution of viewing times, number of fixations, time into the trial of first saccade
to local facial features, and the temporal and spatial characteristics of viewing patterns across the facial images. However,
there was a greater probability of re-fixation of the eye region of unfamiliar faces during the first few seconds of the trial
suggesting that the eyes are important for the initial encoding of identity. Indeed, the highest fixation density was found
in the eye region of all the face images. The viewing duration and the number of fixations per image decreased when inverted
or scrambled faces were presented. The eye region in these modified images remained the primary area of fixation. However,
the number of fixations directed to the eyes decreased monotonically from the upright images through the inverted versions
to the scrambled face images. Nonetheless, the eyes remain the most salient facial substructure regardless of the arrangement
of other features, although the extent of salience which they attain may depend both on the low level properties of the eyes
and on the global arrangement of facial features.
Electronic Publication 相似文献
2.
The addition of other respiratory illnesses such as flu could cripple the healthcare system during the coronavirus disease 2019 (COVID-19) pandemic. An annual seasonal influenza vaccine is the best way to help protect against flu. Fears of coronavirus have intensified the shortage of influenza shots in developing countries that hope to vaccinate many populations to reduce stress on their health services. We present an inventory-location mixed-integer linear programming model for equitable influenza vaccine distribution in developing countries during the pandemic. The proposed model utilizes an equitable objective function to distribute vaccines to critical healthcare providers and first responders, elderly, pregnant women, and those with underlying health conditions. We present a case study in a developing country to exhibit efficacy and demonstrate the optimization model’s applicability. 相似文献
3.
Identification and validation of genes involved in the pathogenesis of colorectal cancer using cDNA microarrays and RNA interference. 总被引:47,自引:0,他引:47
Noelle Sevilir Williams Richard B Gaynor Shane Scoggin Udit Verma Tunc Gokaslan Clifford Simmang Jason Fleming Denise Tavana Eugene Frenkel Carlos Becerra 《Clinical cancer research》2003,9(3):931-946
PURPOSE: The purpose of this study was to profile gene expression changes in colorectal tumors to identify new targets and strategies for the management of this disease. EXPERIMENTAL DESIGN: cDNA microarray analysis was used to detect differences in gene expression between normal tissue and colon tumors and polyps isolated from 20 patients. To identify genes that are important in regulating the growth properties of colorectal cancer, RNA interference (RNAi) was used to disrupt expression of several of the overexpressed genes in a colon tumor cell line, HCT116, which showed similar patterns of gene expression as many of the patient tumors. RESULTS: Expression changes of > or =2-fold in approximately one-third of the patients were consistently observed for 2632 of a total of 9592 genes (574 up-regulated genes and 2058 down-regulated genes). Subsequent analysis of 13 genes by quantitative real-time PCR confirmed the reliability of this analysis. RNAi-mediated disruption of the expression of one of these genes, survivin, a potent inhibitor of apoptosis, severely reduced tumor growth both in vitro and in an in vivo xenograft model. CONCLUSIONS: The combined use of microarray analysis and RNAi provides an excellent system to define the role of specific genes that are up-regulated in cancer lead to the increased in vitro and in vivo growth of colon tumors. 相似文献
4.
5.
Nikoo Hamzeh Sasan Moghimi Golshan Latifi Massood Mohammadi Nassim Khatibi Shan C. Lin 《国际眼科》2015,8(6):1151-1155
AIM: To assess lens thickness measurements with anterior segment-optical coherence tomography (AS-OCT) in comparison with A-scan ultrasonography (A-scan US).
METHODS: There were 218 adult subjects (218 eyes) aged 59.2±9.2y enrolled in this prospective cross-sectional study. Forty-three eyes had open angles and 175 eyes had narrow angles. Routine ophthalmic exam was performed and nuclear opacity was graded using the Lens Opacities Classification System III (LOCS III). Lens thickness was measured by AS-OCT (Visante OCT, Carl Zeiss Meditec, Dublin, CA, USA). The highest quality image was selected for each eye and lens thickness was calculated using ImageJ software. Lens thickness was also measured by A-scan US.
RESULTS: Interclass correlations showed a value of 99.7% for intra-visit measurements and 95.3% for inter-visit measurements. The mean lens thickness measured by AS-OCT was not significantly different from that of A-scan US (4.861±0.404 vs 4.866±0.351 mm, P=0.74). Lens thickness values obtained from the two instruments were highly correlated overall (Pearson correlation coefficient=0.81, P<0.001), and in all LOCS III specific subgroups except in grade 5 of nuclear opacity. Bland-Altman analysis revealed a 95% limit of agreement from -0.45 to 0.46 mm. Lens thickness difference between the two instruments became smaller as the lens thickness increased and AS-OCT yielded smaller values than A-scan US in thicker lens (β=-0.29, P<0.001)
CONCLUSION: AS-OCT-derived lens thickness measurement is valid and comparable to the results obtained by A-scan US. It can be used as a reliable noncontact method for measuring lens thickness in adults with or without significant cataract. 相似文献
6.
Abbas Motalebizadeh Hasan Bagheri Sasan Asiaei Nasim Fekrat Abbas Afkhami 《RSC advances》2018,8(48):27091
A smartphone-based microfluidic platform was developed for point-of-care (POC) detection using surface plasmon resonance (SPR) of gold nanoparticles (GNPs). The simultaneous colorimetric detection of trace arsenic and mercury ions (As3+ and Hg2+) was performed using a new image processing application (app). To achieve this goal, a microfluidic kit was fabricated using a polydimethylsiloxane (PDMS) substrate with the configuration of two separated sensing regions for the quantitative measurement of the color changes in GNPs to blue/gray. To fabricate the microfluidic kit, a Plexiglas mold was cut using a laser based on the model obtained from AutoCAD and Comsol outputs. The colorimetric signals originated from the formation of nanoparticle aggregates through the interaction of GNPs with dithiothreitol – 10,12-pentacosadiynoic acid (DTT-PCDA) and lysine (Lys) in the presence of As3+ and Hg2+ ions. This assembly exhibited the advantages of simplicity, low cost, and high portability along with a low volume of reagents and multiplex detection. Heavy Metals Detector (HMD), as a new app for the RGB reader, was programmed for an Android smartphone to quantify colorimetric analyses. Compared with traditional image processing, this app provided significant improvements in sensitivity, time of analysis, and simplicity because the color intensity is measured through a new normalization equation by converting RGB to an Integer system. As a simple, real-time, and portable analytical kit, the fabricated sensor could detect low concentrations of As3+ (710 to 1278 μg L−1) and Hg2+ (10.77 to 53.86 μg L−1) ions in water samples at ambient conditions.A smartphone-based microfluidic platform was developed for point-of-care (POC) detection using surface plasmon resonance (SPR) of gold nanoparticles (GNPs). 相似文献
7.
Anthony W.H. Chan Jianhong Zhong Sarah Berhane Hidenori Toyoda Alessandro Cucchetti KeQing Shi Toshifumi Tada Charing C.N. Chong Bang-De Xiang Le-Qun Li Paul B.S. Lai Vincenzo Mazzaferro Marta García-Fiñana Masatoshi Kudo Takashi Kumada Sasan Roayaie Philip J. Johnson 《Journal of hepatology》2018,68(6):1284-1293
8.
Sasan Tavana Masoumeh Alizadeh Seyed Amir Mohajerani Seyed Mohammadreza Hashemian 《Nigerian medical journal》2015,56(4):258-262
Background:
Sarcoidosis is a systemic multi-organ granulomatous disease of unknown etiology that is characterized by the presence of granuloma in various organs. The clinical features of sarcoidosis are heterogeneous but pulmonary involvement is cardinal manifestations. The aim of this study was to determine radiologic, clinical and laboratory findings of patients with sarcoidosis.Patients and Methods:
In a cross-sectional study, all patients visiting sarcoidosis clinic were enrolled in the study. Computed tomography (CT) scan was obtained and lab exams were obtained from patient and reports were recorded in data sheet.Results:
Total of 55 patients with sarcoidosis were enrolled in the study. The average of age was 44.6 (range 25-62) years. Thirty-seven patients were male and 18 were female. The most common extra-pulmonary manifestation was arthritis (in 18% of cases) and then lupus pernio (12.8%) and uveitis (10.9%). Bilateral hilar adenopathy and para tracheal lymphadenopathy was observed in 39(70%) and 22 (40%) of patients. Parenchymal nodules (30%), bronchiectasia (25%), ground-glass opacification (18%) were the most common findings. Percentages of patients with dyspnea were 29% and percentages of patients with cough were 21%. Among abnormal lab tests, high urine calcium (Ca) were positive in 21% and high angiotensin-converting enzyme (ACE) in 16% of patients.Conclusion:
Pulmonary involvements are both fibrosis and granulomatosis and the most common manifestations are parenchymal nodules, bronchiectasia and high-grade fibrosis. The most common extra-pulmonary involvement is arthritis. Lab tests are non-specific and have no correlation with duration or severity of disease. 相似文献9.
Strains within bone play an important role in the remodelling process and the mechanisms of fracture. The ability to assess these strains in vivo can provide clinically relevant information regarding bone health, injury risk, and can also be used to optimise treatments. In vivo bone strains have been investigated using multiple experimental techniques, but none have quantified 3D strains using non-invasive techniques. Digital volume correlation based on clinical MRI (DVC-MRI) is a non-invasive technique that has the potential to achieve this. However, before it can be implemented, uncertainties associated with the measurements must be quantified. Here, DVC-MRI was evaluated to assess its potential to measure in vivo strains in the talus. A zero-strain test (two repeated unloaded scans) was conducted using three MRI sequences, and three DVC approaches to quantify errors and to establish optimal settings. With optimal settings, strains could be measured with a precision of 200 με and accuracy of 480 με for a spatial resolution of 7.5 mm, and a precision of 133 με and accuracy of 251 με for a spatial resolution of 10 mm. These results demonstrate that this technique has the potential to measure relevant levels of in vivo bone strain and to be used for a range of clinical applications. 相似文献
10.
Sasan R. Fereidouni Timm C. Harder Anja Globig Elke Starick 《Influenza and other respiratory viruses》2014,8(6):613-616