Publications by authors named "Javad Maleki"

We present a novel design for an all-dielectric metasurface ultra-sensitive refractive index (RI) sensor, characterized by a high-quality factor (Q) and figure of merit (FOM). This design incorporates two high-order toroidal modes, including electric toroidal quadrupole ([Formula: see text]​) and magnetic toroidal quadrupole ([Formula: see text]​) based on quasi‑bound states in the continuum (q-BIC) resonances. Our findings demonstrate the feasibility of switching between [Formula: see text] and [Formula: see text]​ through various symmetry-breaking mechanisms.

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For the first time, an all-dielectric metasurface ultra-sensitive refractive index (RI) sensor with very high quality factor (QF) and figure of merit (FOM), with Fano-magnetic toroidal quadrupole (MTQ) resonance enabled by bound state in continuum (BIC) in terahertz (THz) region was designed. Furthermore, the MTQ resonance in the THz due to a distortion of symmetry-protected bound states in the continuum in the designed structure was investigated. Also, to achieve the dark mode, a combination of three methods including (i) breaking the symmetry, (ii) design of complex structures, and (iii) changing the incident angle was utilized.

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In laser science and industry, considerable effort is directed toward designing fibers for fiber laser and fiber amplifier applications, each of which offers a particular advantage over the others. Evanescently coupled multicore fibers, however, have been studied less extensively due to the relatively small mode area in the single-mode regime. Here, by proposing a new structure with stress-applying parts in a 37-core fiber and optimizing this structure through a comprehensive framework, we present 21 solutions characterized by large-mode-area and high beam quality in the single-mode, single-polarization regime.

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The contamination of melamine was evaluated in 69 infants along with follow up formula samples collected from the market for the first time in Iran using HPLC method. Since there are no previous data concerning the contamination level of melamine in all brands of infant formula samples consumed using the HPLC method in Iran, this study is the first investigation in this regard. Our results showed that melamine contamination was found in 65% of samples, where mean and maximum levels of melamine were 0.

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Ochratoxin A (OTA) is one of the most important mycotoxins that contaminate a broad range of agricultural and food products. In this study, the occurrence of OTA in available brands of grape juice in Iran purchased from retail outlets or producer were determined for the first time using high-performance liquid chromatography (HPLC) with immunoaffinity columns(IAC) as the clean-up step. The average recoveries for OTA in grape juice ranged from 54.

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HTLV-1 and HIV-1 are two major causes for severe T-cell leukemia disease and acquired immune deficiency syndrome (AIDS). HTLV-1 protease, a member of aspartic acid protease family, plays important roles in maturation during virus replication cycle. The impairment of these proteases results in uninfectious HTLV-1virions.

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Changes in human environment and lifestyle over the last century have caused a dramatic increase in the occurrence of diabetes. Research of past decades illustrated that vitamin D and E have a key role in the improvement of diabetes by reducing oxidative stress, protein glycosylation, insulin resistance and also improving beta cell function. Binding properties and conformational changes of human insulin upon interaction with vitamins D and E (α-tocopherol) were investigated by spectroscopy, differential scanning calorimetry (DSC) and molecular dynamic simulation.

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