Four novel mutations in the androgen receptor gene from Vietnamese patients with androgen insensitivity syndrome

Nguyen Thu Hien,Nguyen Duc Quan,Kim Lien Nguyen Thi,Thi Thanh Ngan Nguyen,Nguyen Thi Phuong Mai,Tran Ngoc Dung,Nguyen Huy Hoang 한국유전학회 2023 Genes & Genomics Vol.45 No.4

Background Androgens and androgen receptor (AR) are critical regulators of the masculinization process in male sexual development. The absence of a functioning AR results in the development of the androgen insensitivity syndrome (AIS), a rare disorder of sexual development (DSD) characterized by the external genitalia feminization, gynecomastia, and impaired spermatogenesis. Objective To determine the AR gene mutations associated with male DSD in four unrelated Vietnamese patients. Methods To detect the disease-causing mutations, whole exome sequencing (WES) was performed on four patients diagnosed with AIS. Sanger sequencing was then used for validation of the identified mutations. Finally, 12 web-based tools, three-dimensional protein modeling software, and the guidelines issued by the American College of Medical Genetics and Genomics were used to assess the potential pathogenicity of these mutations. Results Four distinct novel mutations, namely c.1834T > A (p.Cys612Ser), c.2122 C > G (p.Leu708Val), c.2630T > G (p.Phe877Cys), and c.2641 C > A (p.Leu881Met) in the AR gene, were identified in four AIS patients using WES. The in silico analysis results revealed that the Cys612, Leu708, Phe877, and Leu881 sites are important for an appropriate response to androgens of the AR, and mutation at these sites can have adverse effects on the AR functions, androgen–AR interaction, and AR signaling pathway. Conclusions WES and in silico analyses strongly suggested that four novel AR mutations are pathogenic and have led to the development of AIS in the four Vietnamese patients under consideration.

Nonlinear dynamic response and vibration of nanocomposite multilayer organic solar cell

Duc, Nguyen Dinh,Seung-Eock, Kim,Quan, Tran Quoc,Long, Dang Dinh,Anh, Vu Minh Elsevier 2018 COMPOSITE STRUCTURES -BARKING THEN OXFORD- Vol.184 No.-

<P><B>Abstract</B></P> <P>In the recent years, organic solar cell (OSC) has attracted much interest of the research community due to its great promise as renewable sources. This paper presents the first analytical approach to investigate the nonlinear dynamic response and vibration of imperfect rectangular nanocompsite multilayer organic solar cell subjected to mechanical loads using the classical plate theory. Nanocompsite organic solar cell consists of five layers of Al, P3HT:PCBM, PEDOT:PSS, IOT and glass. Motion and compatibility equations are derived using the classical plate theory and taking into account the effects of initial geometrical imperfection and geometrical nonlinearity in Von Karman – Donnell sense. The Galerkin method and fourth – order Runge – Kutta method are used to give explicit expressions of natural frequencies, nonlinear frequency – amplitude relation and nonlinear dynamic responses of nanocompsite organic solar cell. The numerical results show the influences of geometrical parameters, the thickness of layers, imperfections, and mechanical loads on the nonlinear dynamic response and nonlinear vibration of nanocompsite organic solar cell.</P>

Frequency-splitting dynamic MRI reconstruction using multi-scale 3D convolutional sparse coding and automatic parameter selection

Nguyen-Duc, Thanh,Quan, Tran Minh,Jeong, Won-Ki Elsevier 2019 Medical image analysis Vol.53 No.-

<P><B>Abstract</B></P> <P>In this paper, we propose a novel image reconstruction algorithm using multi-scale 3D convolutional sparse coding and a spectral decomposition technique for highly undersampled dynamic Magnetic Resonance Imaging (MRI) data. The proposed method recovers high-frequency information using a shared 3D convolution-based dictionary built progressively during the reconstruction process in an unsupervised manner, while low-frequency information is recovered using a total variation-based energy minimization method that leverages temporal coherence in dynamic MRI. Additionally, the proposed 3D dictionary is built across three different scales to more efficiently adapt to various feature sizes, and elastic net regularization is employed to promote a better approximation to the sparse input data. We also propose an automatic parameter selection technique based on a genetic algorithm to find optimal parameters for our numerical solver which is a variant of the alternating direction method of multipliers (ADMM). We demonstrate the performance of our method by comparing it with state-of-the-art methods on 15 single-coil cardiac, 7 single-coil DCE, and a multi-coil brain MRI datasets at different sampling rates (12.5%, 25% and 50%). The results show that our method significantly outperforms the other state-of-the-art methods in reconstruction quality with a comparable running time and is resilient to noise.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Convolutional dictionary reconstructs high-frequency component of MRI images well. </LI> <LI> Temporal total variation reconstructs low-frequency component of MRI images well. </LI> <LI> Multi-scale dictionary improves MRI reconstruction quality. </LI> <LI> Elastic net regularization works better than L1 or L2 regularization only. </LI> <LI> Genetic algorithm automatically finds optimal parameters for MRI reconstruction. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Potential to mitigate ammonia emission from slurry by increasing dietary fermentable fiber through inclusion of tropical byproducts in practical diets for growing pigs

Quan Hai Nguyen,Phung Dinh Le,Channy Chim,Ngoan Duc Le,Veerle Fievez 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.4

Objective: Research was conducted to test the effect of including fiber-rich feedstuffs in practical pig diets on nutrient digestibility, nitrogen balance and ammonia emissions from slurry. Methods: Three Vietnamese fiber sources were screened, namely cassava leaf meal (CL), cassava root residue (CR), and tofu by-product (TF). Accordingly, a control diet (Con) with 10% of dietary non-starch polysaccharides (NSP) and three test diets including one of the three fiber-rich feedstuffs to reach 15% of NSP were formulated. All formulated diets had the same level of crude protein (CP), in vitro ileal protein digestible and metabolisable energy, whereas the in vitro hindgut volatile fatty acid (VFA) production of the test diets was 12% to 20% higher than the control diet. Forty growing barrows with initial body weight at 28.6±1.93 kg (mean±standard deviation) were allocated to the four treatments. When pigs reached about 50 kg of body weight, four pigs from each treatment were used for a nitrogen balance trial and ammonia emission assessment, the remaining six pigs continued the second period of the feeding trial. Results: The TF treatment increased fecal VFA by 33% as compared with the control treatment (p = 0.07), suggesting stimulation of the hindgut fermentation. However, urinary N was not significantly reduced or shifted to fecal N, nor was slurry pH decreased. Accordingly, ammonia emissions were not mitigated. CR and CL treatments failed to enhance in vivo hindgut fermentation, as assessed by fecal VFA and purine bases. On the contrary, the reduction of CP digestibility in the CL treatment enhanced ammonia emissions from slurry. Conclusion: Dietary inclusion of cassava and tofu byproducts through an increase of dietary NSP from 10% to 15% might stimulate fecal VFA excretion but this does not guarantee a reduction in ammonia emissions from slurry, while its interaction with protein digestibility even might enhance enhanced ammonia emission.

Compressed Sensing MRI Reconstruction Using a Generative Adversarial Network With a Cyclic Loss

Quan, Tran Minh,Nguyen-Duc, Thanh,Jeong, Won-Ki IEEE 2018 IEEE transactions on medical imaging Vol.37 No.6

<P>Compressed sensing magnetic resonance imaging (CS-MRI) has provided theoretical foundations upon which the time-consuming MRI acquisition process can be accelerated. However, it primarily relies on iterative numerical solvers, which still hinders their adaptation in time-critical applications. In addition, recent advances in deep neural networks have shown their potential in computer vision and image processing, but their adaptation to MRI reconstruction is still in an early stage. In this paper, we propose a novel deep learning-based generative adversarial model, <I>RefineGAN</I>, for fast and accurate CS-MRI reconstruction. The proposed model is a variant of fully-residual convolutional autoencoder and generative adversarial networks (GANs), specifically designed for CS-MRI formulation; it employs deeper generator and discriminator networks with cyclic data consistency loss for faithful interpolation in the given under-sampled <TEX>$k$</TEX>-space data. In addition, our solution leverages a chained network to further enhance the reconstruction quality. <I>RefineGAN</I> is fast and accurate—the reconstruction process is extremely rapid, as low as tens of milliseconds for reconstruction of a <TEX>$256\times 256$</TEX> image, because it is one-way deployment on a feed-forward network, and the image quality is superior even for extremely low sampling rate (as low as 10%) due to the data-driven nature of the method. We demonstrate that <I>RefineGAN</I> outperforms the state-of-the-art CS-MRI methods by a large margin in terms of both running time and image quality via evaluation using several open-source MRI databases.</P>

Landscapes and Ecosystems of Tropical Limestone: Case Study of the Cat Ba Islands, Vietnam

Quan Nguyen Van,Thanh Tran Duc,Huy Dinh Van 한국생태학회 2010 Journal of Ecology and Environment Vol.33 No.1

The Cat Ba Islands in Hai Phong City, northern Vietnam, consist of a large limestone island with a maximum height of 322 m above sea level and 366 small limestone islets with a total area of about 180 km2. The islands are relicts of karst limestone mountains that became submerged during the Holocene transgression 7000 – 8000 year ago. The combination of the longtime karst process and recent marine processes in the monsoonal tropical zone has created a very diversity landscape on the Cat Ba Islands that can be divided into 3 habitat types with 16 forms. The first habitat type is the karst mountains and hills, including karst mountains and hills, karst valleys and dolines, karst lakes, karst caves, and old marine terraces. The second habitat type is the limestone island coast, including beaches, mangrove marshes, tidal flats, rocky coasts, marine notch caves, marine karst lakes, and bights. The third habitat type is karst plains submerged by the sea, including karst cones (fengcong) and towers (fengling), bedrock exposed on the seabed, sandy mud seabed, and submerged channels. Like the landscape, the biodiversity is also high in ecosystems composed of scrub cover – bare hills,rainy tropical forests, paddy fields and gardens, swamps, caves, beaches, mangrove forests, tidal flats, rocky coasts, marine krast lakes, coral reefs, hard bottoms, seagrass beds and soft bottoms. The ecosystems on the Cat Ba Islands that support very high species biodiversity include tropical evergreen rainforests, soft bottoms; coral reefs, mangrove forests, and marine karst lakes. A total of 2,380 species have been recorded in the Cat Ba Islands, included 741 species of terrestrial plants; 282 species of terrestrial animals; 30 species of mangrove plants; 287 species of phytoplankton; 79 species of seaweed; 79 species of zooplankton; 196 species of marine fishes; 154 species of corals; and 538 species of zoobenthos. Many of these species are listed in the Red Book of Vietnam as endangered species, included the white-headed or Cat Ba langur (Trachypithecus poliocephalus), a famous endemic species. Human activities have resulted in significantly changes to the landscape end ecosytems of the Cat Ba islands; however, many natural aspects of the islandsd have been preserved. For this reason, the Cat Ba Islands were recognized as a Biological Reserved Area by UNESCO in 2004.

Landscapes and Ecosystems of Tropical Limestone: Case Study of the Cat Ba Islands, Vietnam

Van, Quan Nguyen,Duc, Thanh Tran,Van, Huy Dinh The Ecological Society of Korea 2010 Journal of Ecology and Environment Vol.33 No.1

The Cat Ba Islands in Hai Phong City, northern Vietnam, consist of a large limestone island with a maximum height of 322 m above sea level and 366 small limestone islets with a total area of about $180\;km^2$. The islands are relicts of karst limestone mountains that became submerged during the Holocene transgression 7000 - 8000 year ago. The combination of the longtime karst process and recent marine processes in the monsoonal tropical zone has created a very diversity landscape on the Cat Ba Islands that can be divided into 3 habitat types with 16 forms. The first habitat type is the karst mountains and hills, including karst mountains and hills, karst valleys and dolines, karst lakes, karst caves, and old marine terraces. The second habitat type is the limestone island coast, including beaches, mangrove marshes, tidal flats, rocky coasts, marine notch caves, marine karst lakes, and bights. The third habitat type is karst plains submerged by the sea, including karst cones (fengcong) and towers (fengling), bedrock exposed on the seabed, sandy mud seabed, and submerged channels. Like the landscape, the biodiversity is also high in ecosystems composed of scrub cover - bare hills, rainy tropical forests, paddy fields and gardens, swamps, caves, beaches, mangrove forests, tidal flats, rocky coasts, marine krast lakes, coral reefs, hard bottoms, seagrass beds and soft bottoms. The ecosystems on the Cat Ba Islands that support very high species biodiversity include tropical evergreen rainforests, soft bottoms; coral reefs, mangrove forests, and marine karst lakes. A total of 2,380 species have been recorded in the Cat Ba Islands, included 741 species of terrestrial plants; 282 species of terrestrial animals; 30 species of mangrove plants; 287 species of phytoplankton; 79 species of seaweed; 79 species of zooplankton; 196 species of marine fishes; 154 species of corals; and 538 species of zoobenthos. Many of these species are listed in the Red Book of Vietnam as endangered species, included the white-headed or Cat Ba langur (Trachypithecus poliocephalus), a famous endemic species. Human activities have resulted in significantly changes to the landscape end ecosytems of the Cat Ba islands; however, many natural aspects of the islandsd have been preserved. For this reason, the Cat Ba Islands were recognized as a Biological Reserved Area by UNESCO in 2004.

The Southern World as a Destination of International Students: an Analysis of 50 Tertiary Education Institutions in Vietnam

Pham, Hiep-Hung,Vuong, Quan-Hoang,Dong, Thi-Kieu-Trang,Nguyen, Tien-Trung,Ho, Manh-Toan,Vuong, Thu-Trang,Hoang, Anh-Duc,Nguyen, Mai-Huong World Association for Triple Helix and Future Stra 2021 Journal of Contemporary Eastern Asia Vol.20 No.1

Traditionally, students from the Southern world tend to cross their national borders to study abroad. However, in recent times, we have observed a trend in which more and more students, both full-time and short-term, select Southern countries as destinations for overseas education. This paper contributes to the sparse literature on the above phenomenon, examining the case of Vietnam. We surveyed 50 universities and colleges about their international student profiles (including statistics and nationalities) and their strategies for attracting international students. The findings of this study provide implications for Vietnam's policymakers and university/college leaders and other Southern countries when implementing the internationalization of tertiary education.