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This paper presents a new diplexer design of a new-coupled composite right/left-handed (CRLH) resonator to serve the LTE applications. The realization of the diplexer is designed as coupled two zeroth order π-CRLH resonators to represent with zero electrical length and hence attaining a significant size reduction. The filters are designed to achieve a desired frequency bandwidth of 4% ∼16.7 Q-factor and ∼0.066 coupling coefficient at a centre frequency of 2.1 and 2.6 GHz with transmission zeros. The diplexer exhibits a rejection level of 15–20 dB while maintaining insertion loss of 1 dB for the Tx and Rx bands. The circuit design concepts are verified using equivalent circuit simulations, full electromagnetic simulations and experimental measurements. In conclusion, a good agreement is perceived between the measured and simulated data with size compactness of 30 × 60 mm2. [ABSTRACT FROM AUTHOR]

A compact low-loss microstrip diplexer with four controllable transmission zeros (TZs), all less than 41 dB, is presented. The diplexer circuit consists of two coupled gap bandpass filters with a T-junction as a combining circuit. Channels' filters metalize SIW resonators loaded with metamaterial cells operated at zeroth order mode for compactness and low loss operation. For each channel, a fractional bandwidth of 1.9% is obtained. Also, two TZs at both sides of the resonant frequency are obtained by mixed electric and magnetic coupling between channels' resonators. Design methodology for filtering response and placing TZs at certain frequencies are discussed in detail. There is a good agreement between simulation and measurement with isolation better than 40 dB. Moreover, the diplexer has a small size of (1.1×1.43 λg2). Lower and higher TZs are located at 4.75 and 5.69 GHz, for the lower channel, and at 5.4 GHz and 6.2 GHz for the higher channel, respectively. [ABSTRACT FROM AUTHOR]

This paper introduces a novel design of compact tunable monopole antenna array, employing composite right/left handed (CRLH) feeding network. The feeding network configuration is coplanar waveguide (CPW). A graphene sheet is placed beneath the CRLH cell to achieve the tunability behavior in the antenna design. The antenna array configuration achieves the tunability function with an accepted gain. The surface conductivity of the graphene sheet is tuned by changing the applied DC bias voltage. The DC voltage changes the chemical potential of the graphene sheet. The antenna array is tuned from 2.5–2.46, 2.43, and 2.42 GHz when the chemical potential of graphene is changed from 0.0, 0.15, and 0.2 eV, respectively. The array antenna has a reasonable gain of 5.34 dB without placing the graphene sheet. By placing the graphene and changing the chemical potential, the array gain values become 4.42, 3.82, and 3.74 dB at the specified chemical potential. The radiation properties of the array are studied at the desired resonant frequency. The proposed design can be fabricated by using the transparent transfer process. All the presented designs are verified using the electromagnetic solver CST Studio. [ABSTRACT FROM AUTHOR]

Early detection of hepatocellular carcinoma (HCC) is crucial for successful therapy. The present work examined the value of ultrastructural morphometric image analysis of hepatocyte nuclei in patients with chronic hepatitis C virus (HCV) versus HCC cases with chronic HCV and the corresponding surgical tumor-free safe margins (TFMs), to highlight any early predictive signs of neoplastic cellular transformation. This work also performed an immunohistochemical assessment of cytokeratin 19 (CK19) and Ki-67-positive cells to visualize any associated proliferative activity in the examined groups. The results showed significant decrease in the hepatocyte nuclear surface areas in the HCC and TFMs versus those in the HCV cases. The hepatocyte nucleolar surface area was significantly increased in the HCC cases versus that in the HCV cases. This increase was associated with a significant increase in Ki-67-positive cells in the HCC cases compared to those in the other groups. Conversely, the mean number of CK 19-positive cells was significantly reduced in the HCC cases compared to the cell numbers in TFMs and HCV cases with severe hepatic fibrosis. Liver progenitor cells (LPCs) were discerned in the reactive ductules and canaliculo-ductular junctions that characterized TFMs. LPCs were sporadically distributed in the liver lobules and reactive bile ductules in the HCC samples. In conclusion, CK 19 represents an important marker for distinguishing between dysplastic and malignant liver nodules. Electron microscopic morphometric image analysis may be considered as adjunct factor for assessing hepatocyte malignant transformation. Wider scale studies are needed to authenticate these results. [ABSTRACT FROM PUBLISHER]

An efficient route for the synthesis of (E)-2-(2-(2-nitrobenzylidene)-hydrazinyl)-4-phenylthiazol-3-ium bromide, (E)-2-(2(substituted benzylidene)hydrazinyl)-4-phenylthiazoles and (E)-4-(4-bromophenyl)-2-(cycloalkylidenehydrazono)-3-phenyl-2,3-dihydrothiazoles by reaction of 1-aryl-2-bromoethanones with 2-(1-substituted methylidene)hydrazinecarbothioamides and cycloalkylidene-N-phenyl-hydrazinecarbothioamides. The structure of the products has been confirmed by using IR, NMR, mass spectrometry and single-crystal X-ray analyses. [ABSTRACT FROM AUTHOR]

Understanding the torrential rainfall and its consequent surface runoff in the Sahara is a crucial issue for better flood protection and water management plans. This is often hampered by the lack of appropriate in situ measurements. Even now the satellite-derived rainfall suffers from great uncertainty. Thus, we adjusted the data obtained from real-time satellite rainfall coverage (HYDIS) using the in situ observed rainfall (Robs). Hydro-morphological parameters were then integrated with the empirical curve number (CN) approach to estimate the surface runoff in Qena, Egypt during the 28 January 2013 flash flood event. We deduced that the study area received a total precipitation (∑Rcum) of ∼35.6 × 106 [mm] and a total rain volume (∑Rvol) of ∼88.9 × 109 [m3] mainly from wadi Qena (89.8%). The majority of the rainfalls fell at light intensity (<2.5 [mm hr−1]). The estimated total surface runoff (∑Qsur) was 26.5 × 106 mm and the total runoff volume (∑Qvol) was 66.2 × 106 [m3]. The total surface transmission losses (∑Tlos) were calculated as 9.1 × 106 [mm], which represents about 25.6% of the total precipitation (∑Rcum) and creates substantial opportunities for alluvial aquifer recharge. The total surface runoff (∑Qsur) and flood magnitude were generally low, therefore, flood influences were restricted to the destruction of some roads in Qena but no fatalities were involved, nevertheless. Most of the running water was contained by El Sail Canal and poured into the Nile River. It is expected that the applied method in this study will be helpful for our understanding and quantification of flood hydrology and contribute to better risk management plan in the arid and hyper-arid regions. [ABSTRACT FROM AUTHOR]