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171.
Background music is one of the most frequently encountered contextual factors that affect cognitive and emotional functions in humans. However, it is still unclear whether music induces similar effects in nonhuman primates. Answering this question might bring insight to the long‐lasting question regarding the ability of nonhuman primates in perceiving and dissociating music from other nonmusical acoustic information. In the present study, macaque monkeys were trained to perform a working memory task that required matching visual stimuli. These stimuli had different emotional content (neutral, negative, and positive). Monkeys performed the task within different background acoustic conditions (music, same‐intensity noise, and silence). We hypothesized that the auditory stimuli might interact with emotional information of visual stimuli and modulate monkeys’ performance. Furthermore, if the effects of music and noise on monkeys’ behavioral measures differ it would mean that monkeys perceived and processed music differently. We found that, monkeys committed more errors and were slower when they encountered stimuli with negative or positive emotional content. In the presence of music, the influence of emotional stimuli on monkeys’ performance significantly differed from those of the neutral stimuli, however, in the presence of noise, the effects of emotional stimuli on monkeys’ performance were not distinguishable. The dissociable effects of music and noise on monkeys’ performance show that the effects of emotional stimuli were dependent on the background acoustic conditions. Our findings indicate that background music and the same‐intensity noise were differentially perceived by monkeys and influenced their cognitive functions.  相似文献   
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In this work, the possibility of preparing a nanoparticle with improved treatment properties was investigated. In this regard, synthesis, characterization, in vitro cytotoxicity and DNA binding of Fe3O4@oleate/oseltamivir magnetic nanoparticles (MNPs) were investigated. Fe3O4 nanoparticles were synthesized via chemical co-precipitation and coated by oleate bilayers. Then, Fe3O4@OA MNPs were functionalized with an antiviral drug (oseltamivir), for better biological applications. The MNPs were subsequently characterized by zeta sizer and Zeta potential measurements, Fourier transform infrared (FT-IR) spectroscopy, vibrating sample magnetometer (VSM) and transmission electron microscopy (TEM) analyses. The TEM image demonstrated that average sizes of Fe3O4@OA/oseltamivir MNPs were about 8?nm. The in vitro cytotoxicity of Fe3O4@OA/oseltamivir MNPs was studied against cancer cell lines (MCF-7 and MDA-MB-231) and compared with oseltamivir drug. The results illustrated that Fe3O4@OA/oseltamivir magnetic nanoparticles have better antiproliferative effects on the mentioned cell lines as compared with oseltamivir. Also, in vitro DNA binding studies were done by UV–Vis, circular dichroism, and Fluorescence spectroscopy. The results indicated that Fe3O4@OA/oseltamivir MNPs bound to DNA via groove binding. Moreover, this magnetic nanofluid has potential for magnetic hyperthermia therapy due to magnetic core of its nanoparticles.

Communicated by Ramaswamy H. Sarma  相似文献   

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Purpose

To study performance of a contact lens sensor (CLS) for 24-hour monitoring of IOP-related short-term patterns and compare with IOP obtained by pneumatonometry.

Methods

Prospective clinical trial. Thirty-one healthy volunteers and 2 glaucoma patients were housed for 24 hours in a sleep laboratory. One randomly selected eye was fitted with a CLS (Triggerfish, Sensimed, Switzerland), which measures changes in ocular circumference. In the contralateral eye, IOP measurements were taken using a pneumatonometer every two hours with subjects in the habitual body positions. Heart rate (HR) was measured 3 times during the night for periods of 6 minutes separated by 2 hours. Performance of CLS was defined in two ways: 1) recording the known pattern of IOP increase going from awake (sitting position) to sleep (recumbent), defined as the wake/sleep (W/S) slope and 2) accuracy of the ocular pulse frequency (OPF) concurrent to that of the HR interval. Strength of association between overall CLS and pneumatonometer curves was assessed using coefficients of determination (R2).

Results

The W/S slope was statistically significantly positive in both eyes of each subject (CLS, 57.0 ± 40.5 mVeq/h, p<0.001 and 1.6 ± 0.9 mmHg/h, p<0.05 in the contralateral eye). In all, 87 CLS plots concurrent to the HR interval were evaluated. Graders agreed on evaluability for OPF in 83.9% of CLS plots. Accuracy of the CLS to detect the OPF was 86.5%. Coefficient of correlation between CLS and pneumatonometer for the mean 24-h curve was R2 = 0.914.

Conclusions

CLS measurements compare well to the pneumatonometer and may be of practical use for detection of sleep-induced IOP changes. The CLS also is able to detect ocular pulsations with good accuracy in a majority of eyes.

Trial Registration

ClinicalTrials.gov NCT01390779  相似文献   
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The encapsulation of live cells with polymeric coat-ings is a versatile approach to modulate or control the response cells to their environment. The layer-by-layer (LbL) self-assembly of nonimmunogenic polyelectrolytes is employed here to attenuate or suppress the binding of antibodies to live red blood cells (RBCs) and, consequently, decrease their inherent immunogenicity toward foreign RBCs. The optimized shell was composed of four bilayers of alginate (AL) and chitosan-graft-phosphorylcholine (CH-PC) surrounded by two bilayers of AL and poly-l-lysine-graft-polyethylene glycol (PLL-PEG). Experimental parameters, including the polyelectrolytes and RBCs concentrations and the cell handling and purification protocols, were optimized to achieve effective encapsulation of live and functional RBCs in suspension. The viability and functionality of coated RBCs were confirmed by a hemolysis assay and by their ability to take up oxygen. The successful immunocamouflage of RBCs was confirmed by observing that the recognition of the ABO/D (Rh) blood group antigens present on the surface of RBCs by their respective antibodies was muted in the case of coated RBCs. The results of this studies mark an important step toward the production of universal RBCs.  相似文献   
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The present study describes the length–weight relationships (LWRs) and condition factors (K) of Alburnoides samiii and Ponticola iranicus in the Sefidroud River from the southern Caspian Sea basin, September 2013 to August 2014. This study presents the first known reference in the FishBase database regarding the LWRs and condition factors for these two indigenous species.  相似文献   
180.
Data Grid integrates geographically distributed resources for solving data sensitive scientific applications. Dynamic data replication algorithms are becoming increasingly valuable in solving large-scale, realistic, difficult problems, and selecting replica with multiple selection criteria—availability, security and time- is one of these problems. The current algorithms do not offer balanced QoS levels and the mechanism of rating QoS parameters. In this paper, we propose a new replica selection strategy, which based on response time and security. However, replication should be used wisely because the storage size of each Data Grid site is limited. Thus, the site must keep only the important replicas. We also present a new replica replacement strategy based on the availability of the file, the last time the replica was requested, number of access, and size of replica. We evaluate our algorithm using the OptorSim simulator and find that it offers better performance in comparison with other algorithms in terms of mean job execution time, effective network usage, SE usage, replication frequency, and hit ratio.  相似文献   
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