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41.
Plasmonic metamaterials are artificial materials typically composed of noble metals in which the features of photonics and electronics are linked by coupling photons to conduction electrons of metal (known as surface _lasmon). These rationally designed structures have spurred interest noticeably since they demonstrate some fascinating properties which are unattainable with naturally occurring materials. Complete absorption of light is one of the recent exotic properties of plasmonic metamaterials which has broadened its application area considerably. This is realized by designing a medium whose impedance matches that of free space while being opaque. If such a medium is filled with some lossy medium, the resulting structure can absorb light totally in a sharp or broad frequency range. Although several types of metamaterials perfect absorber have been demonstrated so far, in the current paper we overview (and focus on) perfect absorbers based on nanocomposites where the total thickness is a few tens of nanometer and the absorption band is broad, tunable and insensitive to the angle of incidence. The nanocomposites consist of metal nanoparticles embedded in a dielectric matrix with a high filling factor close to the percolation threshold. The filling factor can be tailored by the vapor phase co-deposition of the metallic and dielectric components. In addition, novel wet chemical approaches are discussed which are bio-inspired or involve synthesis within levitating Leidenfrost drops, for instance. Moreover, theoretical considerations, optical properties, and potential application of perfect absorbers will be presented. 相似文献
42.
Maryam Farzad Fereydoun Layeghi Ali Asgari Seyed Ali Hosseini Mehdi Rassafiani 《Journal of hand and microsurgery》2014,6(1):27-34
The objective of the study is to provide information about non disease specified outcome measures which evaluate disability in patients who have impairments in hand and upper extremity and to find the extent to which they are evaluating “disability” based on ICF hand Core Set (activity limitation and participation restriction). MEDLINE, CINAHL, GOOGLE SCHOLAR , OVID and SCIENCE DIRECT databases were systematically searched for studies on non disease specified outcome measures used to evaluate upper extremity function; only studies written in English were considered. We reviewed titles and abstracts of the identified studies to determine whether the studies met predefined eligibility criteria (eg, non disease specified out come measures used in hand injured patients). All the outcome measures which had eligibility included. After full text review ,7 non disease specified outcome measures in hand were identified. Studies were extracted, and the information retrieved from them. All the outcome measures which had incuded, were linked with ICF hand core set disability part (activity and participation). All of them only linked to 16 (42 %) components of ICF hand Core Set, which were most activity and less participation from ICF. None of the non disease specified out come measures in hand injuries cover all domains of disability from the ICF Hand Core Set. 相似文献
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Nastaran Bagherian-Afrakoti Abbas Alipour Mehdi Pourasghar 《Health care for women international》2018,39(6):684-696
The choice of casarean deliveries by mothers is highly influenced by inadequate knowldge and negative attitudes towards vaginal birth. In this semi-experimental study, we compared knowledge, attitude, and decision making about modes of delivery between nulliparous pregnant women who received eight sessions of group consultation and those who took routine prenatal education. Contrary to the control group, the improvement of knowledge and attitudes were significant in the consultation group (p < 0.001), as well as mothers' decisions for vaginal birth (p = 0.03). Group consultation is an appropriate approach to improving knowledge, attitudes, and tendencies of mothers toward natural birth. 相似文献
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Behnam Rashidieh Mohharam Valizadeh Vahideh Assadollahi Mohammad Mehdi Ranjbar 《American journal of cancer research》2015,5(11):3400-3406
MLN4924 is an experimental cancer drug known as inhibitor of NEDD8-activating enzyme (NAE). This anti-tumor candidate is a selective small-molecule inhibitor of NAE which is conjugated to cullin protein on Cullin-RING ligases (CRLs). This covalent modification actives cullin complex to recruit an ubiquitin-charged E2 and leads to downstream target protein polyubiquitination and proteasomal degradation. MLN4924, which can form a covalent adduct with NEDD8, and block NAE at the first step in this pathway, has shown anti-tumor activity in many kinds of cancer cell lines and also xenograft models, including lung cancer, colon cancer, melanoma and lymphoma. The anti-tumor activity of MLN4924 results from inactivation of CLRs, which causes DNA re-replication and inhibition of nuclear factor (NF)-κB signaling, thus leading to cancer cell death. A mutation can reduce the enzyme’s sensitivity to MLN4924. Verma et al. in 2013 studied on molecular dynamics simulation of a mutant A171T and consequently found out that this mutation reduce MLN4924 interaction with DNA Binding site of enzyme as a result of reduction of enzyme affinity to ATP. One year later, in 2014, Wei Xu et al. carried out a research on inhibitor resistant cell lines and revealed that a couple of mutations so called Y352H and I310N leads to enzyme resistance to MLN4924 inhibitor, interestingly, the cause reported was the increase of enzyme affinity to ATP. As in Wei Xu et al. experiment the molecular dynamics simulation was not considered, present study is conducted to identify enzyme mutation mechanism by molecular dynamics approach using advantages of Gromacs software version 4.5.6. 相似文献
47.
Rostam YAZDANI Iraj SHARIFI Mehdi BAMOROVAT Mohammad Ali MOHAMMADI 《Iranian Journal of Parasitology》2014,9(2):282-285
Human linguatulosis poses an important medical and veterinary concern in endemic countries. Animals, as reservoir host, play a major role in transmission of infestation and epidemiology of the disease. This study reports a case of human linguatulosis caused by Linguatula serrata in the city of Kerman, South-eastern Iran. A woman suffering from upper respiratory symptoms is presented. The patient consumed raw liver of sheep who was admitted to the Afzalipour University Hospital in Kerman for the symptoms of upper respiratory tract. In microscopic examination of the nasopharyngeal discharge, L. serrata was detected. This report has future medical implication in precise diagnosis of L. serrata in patients with complaints of nasopharyngeal symptoms. 相似文献
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Matthieu Heidet Abdel Abdel Wahab Vahid Ebadi Yann Cogne Charlotte Chollet-Xemard Mehdi Khellaf 《The Journal of emergency medicine》2019,56(3):279-281
Background
Bodybuilding is a demanding sport, which requires high-volume, high-resistance weight training and augmented nutritional intake, toward an increase of overall body muscle mass accompanied by an overall decrease of body fat percentage and mass. Among bodybuilders, the use of various legal and illegal supplements is common. These supplements may be naturally occurring or man-made.Case Report
We discuss the case of a 30-year-old male bodybuilder presenting with coma due to severe hypoglycemia from unknown cause, necessitating iterative glucose infusions, which was subsequently found to be related to cryptic insulin injections.Why Should an Emergency Physician Be Aware of This?
In strength athletes, especially amateurs, the recourse to performance-enhancement drugs (e.g., insulin) is frequent. Beyond the specificity of care required for surreptitious insulin intoxication, emergency physicians should be alert to the possibility that exogenous insulin has been injected for use as an ergogenic aid by bodybuilders and others seeking to increase their body muscle mass when they encounter a patient with a decreased level of consciousness and treatment-refractory hypoglycemia. Moreover, in case of suspicion of such intoxication, the use of other illegal supplements should be screened, due to potentially associated risks of complication. 相似文献50.