γ-Irradiation effects on the thermal and optical properties of undoped and eosin doped 70/30 (wt/wt%) PVA/glycogen films

F.H. Abd El-kader,S.A. Gaafar,K.H. Mahmoud,S.I. Bannan,M.F.H. Abd El-kader 한국물리학회 2008 Current Applied Physics Vol.8 No.1

Differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), UV/visible spectra and colour detection of pristine and cirradiated undoped and eosin-doped 70/30 (wt/wt%) PVA/glycogen has been measured. The kinetic parameters such as the activation energy, entropy, enthalpy and free energy for all investigated samples were determined using Coats–Redfern relation. The shift of Tg position towards lower temperatures with increasing c-doses reflect that the degradation process is the predominant one. The values of absorbance and optical parameters in UV/visible range for c-irradiated blend sample doped with eosin showed no significant variation with increasing c-doses. This reflects that the addition of eosin to 70/30 (wt/wt%) PVA/glycogen makes it more resistant to c-radiolysis. The calculated colour parameters such as L*, U*, V*, C*, hue and Ye were found to be dependent on addition of eosin and c-irradiation. Differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), UV/visible spectra and colour detection of pristine and cirradiated undoped and eosin-doped 70/30 (wt/wt%) PVA/glycogen has been measured. The kinetic parameters such as the activation energy, entropy, enthalpy and free energy for all investigated samples were determined using Coats–Redfern relation. The shift of Tg position towards lower temperatures with increasing c-doses reflect that the degradation process is the predominant one. The values of absorbance and optical parameters in UV/visible range for c-irradiated blend sample doped with eosin showed no significant variation with increasing c-doses. This reflects that the addition of eosin to 70/30 (wt/wt%) PVA/glycogen makes it more resistant to c-radiolysis. The calculated colour parameters such as L*, U*, V*, C*, hue and Ye were found to be dependent on addition of eosin and c-irradiation.

Cooperative Relaying Using Space-Time Block Coded Non-orthogonal Multiple Access

Kader, Md. Fazlul,Shin, Soo Young IEEE 2017 IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY Vol.66 No.7

<P>Non-orthogonal multiple access (NOMA) has attracted significant attention in the research community as a potential radio access technology for future wireless networks. In this work, we propose a two-phase cooperative decode-and-forward (DF) relaying scheme based on Alamouti (2 x 1 multiple-input single-output mode) space-time block-coded non-orthogonal multiple access (STBC-NOMA). Closed-form solutions for ergodic sum capacity and outage probability of the proposed scheme are analyzed over independent Rayleigh fading channels. Asymptotic approximations for ergodic sum capacity, outage probability, and outage sum capacity at the high signal-to-noise ratio regime are also provided. It has been pointed out that the proposed cooperative relaying system (CRS) using STBC-NOMA can attain significant performance gains compared to the conventional CRS using NOMA and the traditional DF relaying schemes. It is also demonstrated that the relay position between the transmitter and the receiver has a significant impact on the performance of the proposed protocol. In addition, the proximity between analytical and simulation results confirms the efficiency of the proposed protocol.</P>

Coordinated Direct and Relay Transmission Using Uplink NOMA

Kader, Md. Fazlul,Shin, Soo Young IEEE 2018 IEEE wireless communications letters Vol.7 No.3

<P>A coordinated direct and relay transmission is proposed using uplink non-orthogonal multiple access (UP-NOMA). A two-user UP-NOMA scenario is considered, where a cell-center user directly communicates with a base station (BS), whereas a cell-edge user needs the assistance of a half-duplex decode-and-forward relay to communicate with the BS. The ergodic sum capacity of UP-NOMA is analyzed under both perfect and imperfect successive interference cancellation. The superiority of UP-NOMA over conventional multiple access is demonstrated through simulation and analysis.</P>

Full-Duplex Non-Orthogonal Multiple Access in Cooperative Relay Sharing for 5G Systems

Kader, Md. Fazlul,Shin, Soo Young,Leung, Victor C. M. IEEE 2018 IEEE Transactions on Vehicular Technology VT Vol.67 No.7

<P>In this paper, a full-duplex (FD) non-orthogonal multiple access (NOMA) scheme for a cooperative relay sharing network (termed as FD-NOMA-RS) is presented, in which two source-destination pairs share a dedicated FD relay FD-R. Following the principle of uplink NOMA, both sources transmit their symbols to FD-R, forming a NOMA pair, by depending on their channel conditions with respect to FD-R. The FD-R then decodes these symbols and simultaneously transmits a superimposed composite signal to the destinations with a processing delay <TEX>$\tau$</TEX> according to the principle of downlink NOMA. The ergodic sum capacity, outage probability and outage sum capacity of FD-NOMA-RS are investigated comprehensively along with analytical derivations, considering both perfect and imperfect interference cancellation. A simulation is conducted to corroborate the correctness of the analysis presented here. Moreover, the effectiveness of FD-NOMA-RS is demonstrated through analysis and simulation and then compared with that of its counterpart, the half-duplex system.</P>

Hypothetical protein predicted to be tumor suppressor: a protein functional analysis

Kader, Md. Abdul,Ahammed, Akash,Khan, Md. Sharif,Ashik, Sheikh Abdullah Al,Islam, Md. Shariful,Hossain, Mohammad Uzzal Korea Genome Organization 2022 Genomics & informatics Vol.20 No.1

Litorilituus sediminis is a Gram-negative, aerobic, novel bacterium under the family of Colwelliaceae, has a stunning hypothetical protein containing domain called von Hippel-Lindau that has significant tumor suppressor activity. Therefore, this study was designed to elucidate the structure and function of the biologically important hypothetical protein EMK97_00595 (QBG34344.1) using several bioinformatics tools. The functional annotation exposed that the hypothetical protein is an extracellular secretory soluble signal peptide and contains the von Hippel-Lindau (VHL; VHL beta) domain that has a significant role in tumor suppression. This domain is conserved throughout evolution, as its homologs are available in various types of the organism like mammals, insects, and nematode. The gene product of VHL has a critical regulatory activity in the ubiquitous oxygen-sensing pathway. This domain has a significant role in inhibiting cell proliferation, angiogenesis progression, kidney cancer, breast cancer, and colon cancer. At last, the current study depicts that the annotated hypothetical protein is linked with tumor suppressor activity which might be of great interest to future research in the higher organism.

Non-orthogonal multiple access for a full-duplex cooperative network with virtually paired users

Kader, Md Fazlul,Shahab, Muhammad Basit,Shin, Soo Young Elsevier 2018 Journal of Computer Communications Vol.120 No.-

<P><B>Abstract</B></P> <P>Non-orthogonal multiple access (NOMA) is recognized as a promising radio access technology for next generation wireless networks. In this paper, a novel full-duplex (FD) cooperative relaying scheme for a NOMA based system (termed FD-NOMA-VP) is proposed, where <I>K</I> similar gain near users and relay-aided <I>N</I> similar gain far users are distributed into different NOMA cluster. In each cluster, one near user is virtually paired (VP) with multiple far users over non-overlapping frequency bands. In FD-NOMA-VP, the near user directly communicates with the base station, whereas far users communicate via a dedicated FD relay, in each cluster. The performance of FD-NOMA-VP is studied comprehensively in terms of the ergodic sum capacity, outage probability, and outage sum capacity along with analytical derivations under both perfect and imperfect interference cancellation (IC) scenarios. The results demonstrate that FD-NOMA-VP shows significant performance gains compared to the conventional multiple access scheme under perfect IC, while the residual interference has a substantial impact on the performance gain under imperfect IC. In addition, a strong agreement between analytical and simulation results affirms the correctness of our analysis.</P>

Potent Suppression of Prostate Cancer Cell Growth and Eradication of Cancer Stem Cells by CD44-targeted Nanoliposome-quercetin Nanoparticles

Kader Turkekul,Suat Erdogan 대한암예방학회 2023 Journal of cancer prevention Vol.28 No.4

The bioavailability of quercetin, a natural compound, is hindered by low solubility, limited absorption, and restricted systemic availability. Therefore, encapsulating it in biocompatible nanoparticles presents a promising solution. This study aimed to target prostate cancer stem cells (CSCs) overexpressing CD44+ receptors as well as cancer cells, employing quercetin-loaded hyaluronic acid-modified nanoliposomes (LP-Quer-HA). Synthesized via a green ethanol injection method, these nanoliposomes had an average diameter of 134 nm and an impressive loading efficiency of 96.9%. Human prostate cancer cells were treated with either 10 μM of free quercetin or the same concentration delivered by LP-Quer-HA for 72 hours. Free quercetin reduced androgen-resistant PC3 cell viability by 16%, while LP-Quer-HA significantly increased cell death to 60%. It induced apoptosis, upregulating cytochrome c, Bax, caspases 3 and 8, and downregulating survivin and Bcl-2 expression. Compared to free quercetin, LP-Quer-HA upregulated E-cadherin expression while inhibiting cell migration and reducing the expression of fibronectin, N-cadherin, and MMP9. Treatment of PC3 cell tumor spheroids with LP-Quer-HA decreased the number of CD44 cells and expression of CD44, Oct3/4 and Wnt. Moreover, LP-Quer-HA inhibited p-ERK expression while increasing p38/MAPK and NF-κB protein expression. In androgen-sensitive LNCaP cells, LP-Quer-HA efficacy was notable, reducing cell viability from 10% to 52% compared to free quercetin. Utilizing HA-modified nanoliposomes as a quercetin delivery system enhanced its potency at lower concentrations, reducing the CD44+ cell population and effectively impeding prostate cancer cell proliferation and migration. These findings underscore the potential of quercetin-loaded cationic nanoliposomes as a robust therapeutic approach

Cooperative spectrum sharing in cognitive radio networks: An interference free approach

Kader, Md Fazlul,Irfan, Mohammad,Shin, Soo Young,Chae, Seog Elsevier 2017 PHYSICAL COMMUNICATION Vol.25 No.1

<P><B>Abstract</B></P> <P>We present a novel interference free dual-hop cooperative spectrum sharing protocol in cognitive radio networks exploiting spatial modulation (SM) at both primary transmitter (PT) and secondary transmitter (ST). A ST equipped with multi-antenna acts as a half-duplex decode-and-forward relay for the primary system. During phase-1, SM is invoked at PT, while ST keeps silent. The information bit stream of PT is mapped into two different sets: the M -ary phase shift keying ( M -PSK)/ M -ary quadrature amplitude modulation ( M -QAM) bits and the antenna index. The ST then exploits iterative-maximum ratio combining ( i -MRC) technique to de-map the block of information bits, transmitted by PT. During phase-2, ST forwards the primary data by activating only one antenna based on its own secondary data exploiting the concept of SM. The PT’s data is then retrieved at the primary receiver (PR) and the secondary receiver (SR) recover its own desired data by detecting only the transmit antenna indices of ST using i -MRC. As a result, mutual interference between primary and secondary systems is avoided and interference cancellation techniques at the PR and SR are no longer needed. In the proposed protocol, the primary user does not need to lease its spectrum or time slots to the secondary user in exchange for cooperation. Moreover, power of ST does not need to be distributed for primary and secondary transmission simultaneously during phase-2. The simulation and analytical results are presented to show effectiveness of the proposed protocol compared to conventional spectrum leasing and superposition coding based overlay protocols.</P>

Exploiting cooperative diversity with non-orthogonal multiple access over slow fading channel

Kader, Md Fazlul,Shin, Soo Young Taylor & Francis 2017 International Journal of Electronics Vol. No.

Esculetin Inhibits the Survival of Human Prostate Cancer Cells by Inducing Apoptosis and Arresting the Cell Cycle

Kader Turkekul,R. Dilsu Colpan,Talha Baykul,Mehmet D. Ozdemir,Suat Erdogan 대한암예방학회 2018 Journal of cancer prevention Vol.23 No.1

Background: Prostate cancer (PCa) is one of the most important causes of death in men and thus new therapeutic approaches are needed. In this study, antiproliferative and anti-migration properties of a coumarin derivative esculetin were evaluated. Methods: Human PCa cell lines PC3, DU145, and LNCaP were treated with various concentrations of esculetin for 24 to 72 hours, and cell viability was determined by the MTT test. Cell cycle and apoptosis were analyzed by using cell-based cytometer. Gene expression levels were assessed by reverse transcription and quantitative real-time PCR, cell migration was determined by the wound healing assay. The protein expression was measured by Western blotting. Results: Esculetin inhibited cell proliferation in a dose- and time-dependent manner. Cell migration was inhibited by esculetin treatment. Administration of esculetin significantly reduced the cells survival, induced apoptosis and caused the G1 phase cell cycle arrest shown by image-based cytometer. The induced expression of cytochrome c, p53, p21 and p27, and down-regulated CDK2 and CDK4 may be the underlying molecular mechanisms of esculetin effect. Esculetin suppressed phosphorylation of Akt and enhanced protein expression of tumor-suppressor phosphatase and tensin homologue. Conclusions: Our findings showed that the coumarin derivative esculetin could be used in the management of PCa. However, further in vivo research is needed. (J Cancer Prev 2018;23:10-17)