Negative Absorption Coefficient of a Weak Electromagnetic Wave Caused by Electrons Confined in Rectangular Quantum Wires in the Presence of Laser Radiation

Nguyen Quang Bau,Thi Thanh Nhan,Nguyen Vu Nhan 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.64 No.4

Analytic expressions for the absorption coefficient (ACF) of a weak electromagnetic wave (EMW)caused by electrons confined in rectangular quantum wires (RQWs) in the presence of laser radiationare calculated using the quantum kinetic equation for electrons in the case of electron-optical phononscattering. The dependence of the ACF of a weak EMW on the intensity E01 and the frequency 1 of the external laser radiation, the intensity E02 and the frequency2 of the weak EMW, thetemperature T of the system and the size L (Lx and Ly) of the RQWs is obtained. The resultsare numerically calculated and discussed for GaAs/GaAsAl RQWs. The numerical results showthat the ACF of a weak EMW in RQWs can have negative values. Thus, in the presence of laserradiation, under proper conditions, a weak EMW is increased. This is different from the similarproblem in bulk semiconductors and from the case without laser radiation

Correlations between abnormalities of morphological details and DNA fragmentation in human sperm

Nguyen, Hiep Tuyet Thi,Dang, Hong Nhan Thi,Nguyen, Thai Thanh Thi,Nguyen, Trung Van,Dang, Thuan Cong,Nguyen, Quoc Huy Vu,Le, Minh Tam The Korean Society for Reproductive Medicine 2022 Clinical and Experimental Reproductive Medicine Vol.49 No.1

Objective: As the associations of sperm DNA fragmentation with morphology have not been examined in detail, this study aimed to investigate the relationship between abnormalities of morphological details and DNA integrity in human sperm. Methods: In this cross-sectional study, men from infertile couples were enrolled at Hue Center for Reproductive Endocrinology and Infertility, Vietnam. Conventional semen parameters, including morphological details, were analyzed following the World Health Organization 2010 criteria. Sperm DNA fragmentation was evaluated using a sperm chromatin dispersion assay. The relationships and correlations between semen parameters, sperm morphology, and the type of halosperm and the DNA fragmentation index (DFI) were analyzed. Results: Among 130 men in infertile couples, statistically significant differences were not found in the sperm halo type between the normal and abnormal sperm morphology groups. The percentage of round-head spermatozoa was higher in the DFI >15% group (16.98%±12.50%) than in the DFI ≤15% group (13.13% ±8.82%), higher values for amorphous heads were found in the DFI >15% group, and lower values for tapered heads were observed in the DFI ≤15% group; however, these differences were not statistically significant. Small-halo sperm and the DFI were positively correlated with round-head sperm (r=0.243, p=0.005 and r=0.197, p=0.025, respectively). Conclusion: The rate of general sperm morphological abnormalities in semen analysis was not related to sperm DNA integrity. However, round sperm heads were closely associated with sperm DNA fragmentation.

Physiological intracytoplasmic sperm injection does not improve the quality of embryos: A cross-sectional investigation on sibling oocytes

Minh Tam Le,Hiep Tuyet Thi Nguyen,Trung Van Nguyen,Thai Thanh Thi Nguyen,Hong Nhan Thi Dang,Thuan Cong Dang,Quoc Huy Vu Nguyen The Korean Society for Reproductive Medicine 2023 Clinical and Experimental Reproductive Medicine Vol.50 No.2

Objective: This study aimed to compare the efficacy of physiological intracytoplasmic sperm injection (PICSI) and intracytoplasmic sperm injection (ICSI) in terms of the fertilization rate and embryo quality using sibling oocyte cycles. Methods: This prospective, cross-sectional study collected data from 76 couples who underwent their first cycle at the Hue Center for Reproductive Endocrinology and Infertility, Vietnam, between May 2019 and November 2021. The inclusion criteria were cycles with at least eight oocytes and a sperm concentration of 5×10⁶/mL. Sperm parameters, sperm DNA fragmentation (SDF), fertilization, and the quality of cleavage-stage embryos on day 2 and blastocysts on day 5 were examined. Results: From 76 ICSI cycles, 1,196 metaphase II (MII) oocytes were retrieved, half of which were randomly allocated to either the PICSI (n=592) or ICSI (n=604) treatment group. The results showed no significant difference between the two groups in terms of fertilization (72.80% vs. 75.33%, p=0.32), day 2 cleavage rate (95.13% vs. 96.04%, p=0.51), blastulation rate (52.68% vs. 57.89%), and high-quality blastocyst rate (26.10% vs. 31.13%, p=0.13). However, in cases where SDF was low, 59 cycles consisting of 913 MII oocytes produced a considerably higher blastulation rate with PICSI than with ICSI (50.49% vs. 35.65%, p=0.00). There were no significant differences between the pregnancy outcomes of the PICSI and ICSI embryo groups following embryo transfer. Conclusion: Using variable sperm quality provided no benefit for PICSI versus ICSI in terms of embryo outcomes. When SDF is low, PICSI appears to be able to produce more blastocysts.

Novel online routing algorithms for smart people-parcel taxi sharing services

Son Nguyen Van,Nhan Vu Thi Hong,Dung Pham Quang,Hoai Nguyen Xuan,Behrouz Babaki,Anton Dries 한국전자통신연구원 2022 ETRI Journal Vol.44 No.2

Building smart transportation services in urban cities has become a worldwide problem owing to the rapidly increasing global population and the development of Internet-of-Things applications. Traffic congestion and environmental concerns can be alleviated by sharing mobility, which reduces the number of vehicles on the road network. The taxi-parcel sharing problem has been considered as an efficient planning model for people and goods flows. In this paper, we enhance the functionality of a current peopleparcel taxi sharing model. The adapted model analyzes the historical request data and predicts the current service demands. We then propose two novel online routing algorithms that construct optimal routes in real-time. The objectives are to maximize (as far as possible) both the parcel delivery requests and ride requests while minimizing the idle time and travel distance of the taxis. The proposed online routing algorithms are evaluated on instances adapted from real Cabspotting datasets. After implementing our routing algorithms, the total idle travel distance per day was 9.64% to 12.76% lower than that of the existing taxi-parcel sharing method. Our online routing algorithms can be incorporated into an efficient smart shared taxi system.

Orodispersible film incorporating nanoparticulate loratadine for an enhanced oral bioavailability

Van Nguyen Khanh,Dang Thu Kim,Vu Linh Thi Dieu,Ha Nhan Thi,Truong Hieu Duy,Tran Tuan Hiep 한국약제학회 2023 Journal of Pharmaceutical Investigation Vol.53 No.3

Purpose Loratadine (LOR), a commonly prescribed antihistamine, has low water solubility but high permeability. In this study, an orodispersible film incorporating the nanoparticulate loratadine was prepared to enhance the oral bioavailability of a poorly water-soluble drug. Methods Nanoparticulate loratadine was formulated using the antisolvent precipitation method and optimized by a singlefactor design based on the particle size and polydispersity index. The optimal formulation was spray-dried and characterized by powder X-ray diffraction and differential scanning calorimetry. Nanoparticulate loratadine was loaded into an orodispersible film using a solvent casting method. Results In the dissolution tests, the nanoparticulate loratadine-loaded orodispersible film exhibited a 6.5-fold higher dissolution rate than the pure loratadine-loaded film and a similar dissolution rate compared to the commercialized orodispersible tablet, Loratadine SPM. In pharmacokinetic studies conducted on rats, the maximum concentration (Cmax) and area under the curve of the plasma concentration–time profile from 0 to 24 h (AUC 0-24 h) of the nanoparticulate loratadine-loaded orodispersible film significantly increased 1.8-fold and 5.8-fold, respectively. The elimination half-life (t1//2) increased 5.1-fold compared to the loratadine-loaded counterpart. Conclusion These results suggest the potential of orodispersible films to improve the oral bioavailability of poorly watersoluble drugs and promote compliance in pediatric and geriatric patients.

Eco-friendly Aqueous Binder-Based LiNi 0.4 Mn 1.6 O 4 Cathode Enabling Stable Cycling Performance of High Voltage Lithium-Ion Batteries with Biomass-Derived Silica

Ngoc Thi Bao Nguyen,Hoang Van Nguyen,Nhan Thanh Tran,Phat Tan Vu,Phung My Loan Le,Man Van Tran 대한금속·재료학회 2023 ELECTRONIC MATERIALS LETTERS Vol.19 No.3

High voltage cathode materials LiNi x Mn 2−x O 4 (x = 0.4; 0.5) have been attracting greater attention in developing high energydensity Li-ion battery technology for electrical vehicles and large-scale applications. The main challenge of high voltagecathodes is severe electrolyte decomposition leading to short cell cycle life. In addition, LiNi 0.4 Mn 1.6 O 4 cathode materialprocessed with polyvinylidene fl uoride (PVdF) binder generally suff ers an oxidation decomposition as well as cathodedelamination from current collectors during cycling. Herein, we suggest using sodium carboxymethyl cellulose (CMC),lithium polyacrylic acid (LiPAA) as water-soluble binders for replacing conventional PVdF in cathode processing to demonstratethe eff ectiveness on long-cycling of half-cell Li || LiNi 0.4 Mn 1.6 O 4 , full-cell SiO 2 -graphite || LiNi 0.4 Mn 1.6 O 4 and SiO 2|| LiNi 0.4 Mn 1.6 O 4 . In half-cell, the cells with water-soluble binders-based cathode exhibited a higher discharge capacity thanthe one using PVdF binder (CMC—126.0 mAh/g; LiPAA—125.7 mAh/g; PVdF—117 mAh/g at C/5, respectively). CMCand LiPAA also improve retention capacity up to 90% after 500 cycles at C/3. Interestingly, LiPAA based electrode exhibitsan excellent rate-capability with discharge capacity of 80 mAh/g at 8C. The stability of electrodes was also investigated byelectrode chemical impedance spectroscopy (EIS) and Scanning electron microscope (SEM). In full-cell, CMC and LiPAAbased cells showed eff ectiveness in decreasing transition metal dissolution and preventing the cathode degradation duringlong-cycling through its excellent capacity retention in 200 cycles at C/3.