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A data set of 140 selected rice varieties from regional registration testing in the Mekong delta with four rice registration groups was studied for quality properties and correlations between each quality parameter and comprehensive taste... more
A data set of 140 selected rice varieties from regional registration testing in the Mekong delta with four rice registration groups was studied for quality properties and correlations between each quality parameter and comprehensive taste quality in this paper. Differences in rice quality among the four registration groups and three taste categories were identified. (1) The three maturity groups of A0, A1, and A2 could be divided into fairly good and medium taste categories only whereas the aromatic group could be divided into three taste categories. (2) In the A0, A1, and A2 groups, the amylose content values of the fairly good taste category were lower than those of the medium taste category in the three groups, by 5.91%, 4.38%, and 6.38%, respectively (P <0.05). However, the gel consistency values of the fairly good taste category were higher than those of the medium one, by 25.79mm, 16.53mm, and 26.66mm, respectively. (3) In the aromatic group, the hulling percentage and mill...
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In this research, ZnO/GO nanocomposites were successfully synthesized by a simple hydrothermal method using graphene oxide (GO) and zinc acetate dihydrate (Zn(CH3COO)2.2H2O) as the reactants. The effect of the hydrothermal reaction time... more
In this research, ZnO/GO nanocomposites were successfully synthesized by a simple hydrothermal method using graphene oxide (GO) and zinc acetate dihydrate (Zn(CH3COO)2.2H2O) as the reactants. The effect of the hydrothermal reaction time on the structure and optical property of the ZnO/GO was systematically investigated. The structure, morphology and chemical composition of the samples were measured by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and Raman and Fourier transform infrared (FTIR) spectroscopy, while the optical properties were measured using photoluminescence spectroscopy. The synthesized products consisted of large quantities of one-dimensional (1D) ZnO nanorods (NRs), which were dispersed uniformly on the GO surface. The XRD and Raman results reveal that the ZnO NRs in the fabricated samples had a hexagonal wurtzite structure with high crystalline qualit...
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Nghiên cứu sử dụng thang đo PERMA profiler để đánh giá chỉ số hạnh phúc của sinh viên Trường Đại học Ngoại ngữ - Đại học Quốc gia Hà Nội (ĐHNN-ĐHQGHN) trong giai đoạn giãn cách xã hội do tác động của đại dịch Covid 19. Về thực tiễn, chỉ... more
Nghiên cứu sử dụng thang đo PERMA profiler để đánh giá chỉ số hạnh phúc của sinh viên Trường Đại học Ngoại ngữ - Đại học Quốc gia Hà Nội (ĐHNN-ĐHQGHN) trong giai đoạn giãn cách xã hội do tác động của đại dịch Covid 19. Về thực tiễn, chỉ số hạnh phúc của sinh viên Trường ĐHNN-ĐHQGHN nói chung và chỉ số hạnh phúc của sinh viên mỗi khóa nói riêng đều ở mức bình thường. Đồng thời, nghiên cứu cũng đánh giá sự tương quan giữa các nhân tố hạnh phúc: “cảm xúc tích cực”, “sự gắn kết”. “mối quan hệ tích cực”, “ý nghĩa cuộc sống”và “những thành tựu của cá nhân” của sinh viên Trường ĐHNN-ĐHQGHN ở mức khá chặt.
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Political participation is one of the fundamental human rights widely recognised in core United Nations international human rights treaties. As an active and responsible member of the international community, Vietnam has continuously... more
Political participation is one of the fundamental human rights widely recognised in core United Nations international human rights treaties. As an active and responsible member of the international community, Vietnam has continuously endeavoured to enforce international commitments and create a legal environment for the equal enjoyment of the political rights of all people, particularly women. However, given the gender characteristics and social stereotypes that have existed for many generations, ethnic minority women and girls are always at a disadvantage within the family and outside society. They face discrimination and compound inequality – both on the grounds of ethnicity and gender – in their living environment. It affects their accessibility, participation and enjoyment of their rights, including the right to participate in politics. This article will study the compatibility between international law and Vietnam’s policies in ensuring the political rights of ethnic minority w...
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This paper provides a refinement of the study of asymptotic behaviour for a class of nonlocal in time telegraph equations with positively singular kernels. Based on fundamental properties of relaxation functions and recent representation... more
This paper provides a refinement of the study of asymptotic behaviour for a class of nonlocal in time telegraph equations with positively singular kernels. Based on fundamental properties of relaxation functions and recent representation of the fundamental solution in [Nonlinear Anal. 193 (2020), 111411], we establish the asymptotic expansions of the variance of the stochastic process for both long-time and short-time, which sharply improves the main result in [Proc. Amer. Math. Soc. 149 (2021), 2067–2080] by removing their technical conditions on the regularly varying behaviours and reformulating the asymptotic expansion in a more natural form. By analysing a new noncommutative operation on a subclass of completely positive functions, we provide a new way to construct finitely many ultraslow subdiffusion processes that are rapidly slower than a given ultraslow kernel. Consequently, we show that for a given completely monotonic ultraslow kernel, there is an induced kernel whose corr...
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Allopurinol (ALP) is commonly used as a drug for gout treatment. However, ALP is known to cause cutaneous adverse reactions (CARs) in patients. The HLA-B*58:01 allele is considered a biomarker of severe CAR (SCAR) in patients with gout,... more
Allopurinol (ALP) is commonly used as a drug for gout treatment. However, ALP is known to cause cutaneous adverse reactions (CARs) in patients. The HLA-B*58:01 allele is considered a biomarker of severe CAR (SCAR) in patients with gout, with symptoms of Stevens Johnson syndrome, and with toxic epidermal necrolysis. However, in patients with gout and mild cutaneous adverse drug reactions (MCARs), the role of HLA-allele polymorphisms has not been thoroughly investigated. In this study, 50 samples from ALP-tolerant patients and ALP-induced MCARs patients were genotyped in order to examine the polymorphisms of their HLA-A and HLA-B alleles. Our results showed that the frequencies of HLA-A*02:01/HLA-A*24:02 and HLA-A*02:01/HLA-A*29:01, the dual haplotypes in HLA-A, in patients with ALP-induced MCARs were relatively high, at 33.3% (7/21), which was HLA-B*58:01-independent, while the frequency of these dual haplotypes in the HLA-A locus in ALP-tolerant patients was only 3.45% (1/29). The H...
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Ultrasonic methods, such as the Ultrasonic Velocity Profile - UVP method, have a number of advantages over other conventional measurement methods. They are non-intrusive, applicable to opaque wall or fluid, and capable of obtaining... more
Ultrasonic methods, such as the Ultrasonic Velocity Profile - UVP method, have a number of advantages over other conventional measurement methods. They are non-intrusive, applicable to opaque wall or fluid, and capable of obtaining instantaneous velocity profiles along a measurement line in real time. This paper reports on the development of a multiwave Doppler UVP method for the measurement of bubbly two-phase flow in a Taylor-Couette flow configuration. Due to its highly complex nature, two-phase flow still attracts considerable interest in both experimental measurement as well as numerical simulation. In this study the new multiwave Doppler UVP method exploits two basic ultrasonic frequencies 2 MHz and 8 MHz. The 2 MHz frequency is for the measurement of the bubble phase. The 8 MHz frequency is for that of the liquid phase. The signal processing technique is based on the pulse repetition Doppler method. A new phase discrimination method is proposed to eliminate bubble velocity in...
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The study was carried out with twenty-four genotypes of rice during the Spring season, 2020 in Hanoi, Vietnam in order to exploit the attributes and divergence of quality properties from existing rice cultivars in North Vietnam. The rice... more
The study was carried out with twenty-four genotypes of rice during the Spring season, 2020 in Hanoi, Vietnam in order to exploit the attributes and divergence of quality properties from existing rice cultivars in North Vietnam. The rice genotypes were characterized based on ten quality parameters of milling, physical appearance and physiochemical characters using Mahalanobis D2 statistic. D2 analysis allocated the 24 genotypes into eight clusters, of which cluster I was the largest with 12 genotypes. The clustering showed the random distribution of genotypes into different clusters indicating that the origin and release duration were not related to the genetic diversity of grain quality. Among different traits, amylose content, length/width ratio and gel consistency were identified as topmost contributors in total divergence. Cluster I possessed a maximum intra-cluster value of 296.34 and the maximum inter-cluster distance was recorded between cluster IV and VI (2247.39) succeeded ...
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The frequencies and diversities of human leukocyte antigen (HLA) alleles and haplotypes are representative of ethnicities. Matching HLA alleles is essential for many clinical applications, including blood transfusion, stem cell... more
The frequencies and diversities of human leukocyte antigen (HLA) alleles and haplotypes are representative of ethnicities. Matching HLA alleles is essential for many clinical applications, including blood transfusion, stem cell transplantation, and tissue/organ transplantation. To date, the information about the frequencies and distributions of HLA alleles and haplotypes among the Kinh Vietnamese population is limited because of the small sample size. In this study, more than 3,750 cord blood units from individuals belonging to the Kinh Vietnamese population were genotyped using PCR sequence-specific oligonucleotide (PCR-SSO) for HLA testing. The results of the study demonstrated that the most frequently occurring HLA-A, -B, -C, and -DRB1 alleles were A*11:01 (25%), A*24:02 (12.3%), A*02:01 (11.2); A*03:03 (8.95%), A*02:03 (7.81%), A*29:01 (7.03%); B*15:02 (15.1%), B*46:01 (10.7%), B*58:01 (7.65%), B*38:02 (7.29%); C*08:01 (17.2), C*07:02 (16.2%), C*01:02 (15.2), C*03:02 (8.3%), C*1...
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Determining structures' dynamic response is a challenging and time-consuming problem because it requires iteratively solving the governing equation of motion with a significantly small time step to ensure convergent results. This... more
Determining structures' dynamic response is a challenging and time-consuming problem because it requires iteratively solving the governing equation of motion with a significantly small time step to ensure convergent results. This study proposes an alternative approach based on the deep learning paradigm working in a complementary way with conventional methods such as the finite element method for quickly forecasting the responses of structures under random wind loads with reasonable accuracy. The approach works in a sequence-to-sequence fashion, providing a good trade-off between the prediction performance and required computation resources. Sequences of known wind loads plus time history response of the structure are aggregated into a 3D tensor input before going through a deep learning model, which includes a long short-term memory layer and a time distributed layer. The output of the model is a sequence of structures' future responses, which will subsequently be used as i...
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Project selection problems on management information system (MIS) are often considered a multi-criteria decision-making (MCDM) for a solving method. These problems contain two aspects, such as interdependencies among criteria and... more
Project selection problems on management information system (MIS) are often considered a multi-criteria decision-making (MCDM) for a solving method. These problems contain two aspects, such as interdependencies among criteria and candidate projects and qualitative and quantitative factors of projects. However, most existing methods reported in literature consider these aspects separately even though these two aspects are simultaneously incorporated. For this reason, we proposed a hybrid method using analytic network process (ANP) and fuzzy logic in order to represent both aspects. We then propose a goal programming model to conduct an optimization for the project selection problems interpreted by a hybrid concept. Finally, a numerical example is conducted as verification purposes.
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This Abstract was submitted to the 9th International Conference on Sustainable Built Environment for the Special Session on Waste in Construction
Ricin has been reported as a potential therapeutic agent for the treatment of various cancers due to its potency. In this study, we succeeded in isolating and purifying total ricin from seeds of the castor bean (ricinus communis) from... more
Ricin has been reported as a potential therapeutic agent for the treatment of various cancers due to its potency. In this study, we succeeded in isolating and purifying total ricin from seeds of the castor bean (ricinus communis) from Vietnam. We also revealed that total ricin showed strong cytotoxicity against melanoma cells; IC50 at 48h was 34.1 ng/mL for SKMEL28 cells and 5.2 ng/mL for HaCaT cells. We examined the ability of total ricin to inhibit tumorigenesis of SKMEL28 cells in vitro. At low concentrations (< 3ng/mL)total ricin did not cause death of HaCaT or SKMEL28 cells but strongly reduced the size of SKMEL28 tumor colonies formed in soft agar. The effect of ricin on tumorigenesis was also confirmed by apoptotic and immunoblot analyses. Our results showed that treatment with total ricin (3 ng/mL) resulted in decreased ERK and pERK expression in SKME28 cells but did not affect expression levels of thosegenes in HaCaT cells. We showed that, although ricin at 1 and 3 ng/mL...
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Recently, non-orthogonal multiple access (NOMA) has been considered as a promising candidate for next-generation mobile communications because it can significantly improve the spectral efficiency of wireless networks. In this paper, we... more
Recently, non-orthogonal multiple access (NOMA) has been considered as a promising candidate for next-generation mobile communications because it can significantly improve the spectral efficiency of wireless networks. In this paper, we investigate a novel solution to enhance the reliability and the supply stability of a downlink NOMA relaying networks, in which we integrate two techniques: (i) simultaneous wireless information and power transfer, i.e. the relay node can harvest the energy from source signals and use this energy to help forward information from source node to two user nodes; and (ii) data buffer aid at relay node, i.e. the data packets received from the source can be stored in a buffer and then be re-transmitted to the destination nodes only when the channel condition is good. The performance of the proposed system is analyzed rigorously to derive the system outage probability and the average packet delay. Furthermore, a power allocation optimization problem to minim...
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Currently, the number of disabled people is increasing rapidly, requiring the development of applications with the aim to establish a communication between the human brain and external assistance devices through a computer, also known as... more
Currently, the number of disabled people is increasing rapidly, requiring the development of applications with the aim to establish a communication between the human brain and external assistance devices through a computer, also known as brain computer interface (BCI). Most commonly, EEG signals are used for BCI system because they have high temporal resolution and are noninvasive. In this study, we focused on classifying EEG signals acquired through two experiments, (1) using two channels C3, C4 and (2) by six channels attached on the motor cortex to distinguish the left and right hand movement imaginations. For the classification task, k-Nearest Neighbor (kNN), Artificial Neural Network (ANN), Support Vector Machine (SVM), and Decision Tree were investigated. Furthermore, we combined the Principal Components Analysis (PCA) method and the Common Spatial Patterns (CSP) method to reduce redundant features in the recorded signals from 6-channel experiments in order to enhance the classification accuracies. The overall accuracy of recognizing two hand movement imaginations was 85% for KNN, 97% for ANN, 97% for SVM and 100% for Randomized Forest respectively with ratio 50% train data and 50% test data. These results show the potential of further developing applications in BCI electric wheel chair. The data is recorded by self-implement EEG system using ADS1299.
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Deep neural networks (DNNs) have recently indicated outstanding performance on image learning feature tasks while Convolutional neural networks (CNNs) have been applied for classification tasks by reducing spectral variations and the... more
Deep neural networks (DNNs) have recently indicated outstanding performance on image learning feature tasks while Convolutional neural networks (CNNs) have been applied for classification tasks by reducing spectral variations and the spectral correlations of the model which existed in images. In this paper, we independently approached our work as a sequence of steps. We first implemented sparse autoencoders as an unsupervised algorithm to obtain learned features in two hidden layers for the DNN model by evaluating the appropriate input features and the optimal number of hidden units, which allow us to validate basic capabilities of the dataset. Secondly, we trained a deep CNN which consisted of five main convolutional layers, followed by Rectified Linear Units (ReLUs) layers, max-pooling layers, three fully-connected layers and a final softmax probability layer, to classify the high-resolution medical images of Computed Tomography (CT) into five anatomical classes, corresponding to five organs in abdominal regions. As a result, we considerably achieved the classification accuracy of 83.74 ± 3.34% in testing. We also visualized the layer representations on CT datasets, where they indicated the state-of-the-art performance, and could hold much promise to initialize further research on computer-aided diagnosis.
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In this paper, a model of dual-beam nonlinear Fabry-Perot interferometer (DBNFPI) for creation laser hollow-Gaussian beam (HGB) is investigated. It includes a thin film of organic dye sandwiched between two optical mirrors, and irradiated... more
In this paper, a model of dual-beam nonlinear Fabry-Perot interferometer (DBNFPI) for creation laser hollow-Gaussian beam (HGB) is investigated. It includes a thin film of organic dye sandwiched between two optical mirrors, and irradiated by two signal and pump laser Gaussian beams. Based on the equation describing the output-input relation of intensities concerning pump intensity and the expression of the spatial intensity distribution of output signal beam (OSB), the range of pump intensity and collection of designed parameters are numerically calculated and discussed for HGB creation. These results give us the opportunity to use DBNFPI for optical trap of low-index dielectric particles.
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In this note, we complement an argument in the proof of Gao [G] regarding the method of factoring multivariate polynomials using partial differential equations (p.d.e.). MIRAMARE – TRIESTE December 2006 Regular Associate of ICTP.... more
In this note, we complement an argument in the proof of Gao [G] regarding the method of factoring multivariate polynomials using partial differential equations (p.d.e.). MIRAMARE – TRIESTE December 2006 Regular Associate of ICTP. nqthang@math.ac.vn ngoannt@yahoo.com 1. In a recent interesting paper [GR], it has been shown that For a given absolutely irreducible polynomial f(x, y) ∈ Z[x, y] there is a lower bound N(f) (which is perhaps the best bound up to now), such that for any prime p > N(f), the reduction modulo p of f is also absolutely irreducible over the finite field Fp with p elements. The method used in the proof of this interesting theorem relies on some ingredients, one of which is the method of factoring multivariate polynomials by using a partial differential equation presented in [G]. In fact, the partial differential equation was considered earlier by Ruppert [Ru1,2], where another bound N (f) (which seems to be larger than N(f)) was presented in [Ru2]. The core of...
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Plastic pollution has become a major global environmental problem. The amount of plastic waste, including microplastics discharged into the environment, is on the increase, causing harm to the environment, ecosystems, especially marine... more
Plastic pollution has become a major global environmental problem. The amount of plastic waste, including microplastics discharged into the environment, is on the increase, causing harm to the environment, ecosystems, especially marine ecosystems, entering the food chain, and affecting human health. Recognizing the environmental risks of plastic waste, the State has issued many legal documents on plastic waste management such as the Law on Environmental Protection (2014, 2020); Law on Environmental Protection Tax 2010; National environmental protection strategy up to 2020, Vision 2030; National strategy on integrated solid waste management up to 2025, Vision 2050, among others. However, there are still many shortcomings to plastic waste management in Vietnam, e.g. there are no effective solutions in reducing, sorting, collecting, reusing, recycling and treating waste. More importantly, public awareness and understanding of microplastic pollution in Vietnam still need improving. Ther...
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We investigate on the localization of nodes in a sensor network based on multidimensional scaling (MDS). The distances of node pairs are given and MDS attempts to locate the position of nodes given the distance matrix. However,... more
We investigate on the localization of nodes in a sensor network based on multidimensional scaling (MDS). The distances of node pairs are given and MDS attempts to locate the position of nodes given the distance matrix. However, conventional MDS addresses the mapping problem using eigenvector decomposition which is complicated in computation, mitigating the efficiency of this approach for real-time applications. In this paper, we introduce a sequential MDS for the fast implementations of MDS for a changing sensor network. The fast-fixed point algorithm is used to initialize the locations of nodes. When the distance matrix is varied due to the movements of nodes, sequential MDS aims at reallocating the nodes with a fast and effective update process. We validated sequential MDS with a number of experiments and shown the proposed approach is superior to conventional MDS when it deals with the location problems of moving nodes of the sensor network. Keywords-Multidimensional Scaling; L...
Software is becoming more and more complex because of higher expectation of users on software services. Some of those services are even unanticipated at the beginning of software implementation as software continues to evolve. As a matter... more
Software is becoming more and more complex because of higher expectation of users on software services. Some of those services are even unanticipated at the beginning of software implementation as software continues to evolve. As a matter of fact, software technology is struggling to keep up with the pace of changes. This situation creates a great challenge to the software industry, namely developing complex software with high quality and low cost in the ever-changing environment. The software engineering community is trying to find an approach to keep the software cost and maintenance within budget. The most effective practice in the modern software industry relies on the component-based approach. Its basic principle is “divide and conquer”. A system can be partitioned into separate modules each of which can be independently implemented. The target system can then be constructed by composing those modules together in a well-defined order. The total development cost can then be sign...
Educational , Scientific and Cultural Organization and International Atomic Energy Agency THE ABDUS SALAM INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS CORESTRICTION PRINCIPLE FOR NON-ABELIAN COHOMOLOGY OF REDUCTIVE GROUP SCHEMES OVER DEDEKIND RINGS OF INTEGERS OF LOCAL AND GLOBAL FIELDS Dedicated tomore
We prove some new results on Corestriction principle for non-abelian cohomology of group schemes over the rings of integers of local and global fields. Some connections with Grothendieck Serre’s conjecture are indicated, and applications... more
We prove some new results on Corestriction principle for non-abelian cohomology of group schemes over the rings of integers of local and global fields. Some connections with Grothendieck Serre’s conjecture are indicated, and applications to the study of class groups of algebraic groups over global fields are given. MIRAMARE – TRIESTE December 2006 Regular Associate of ICTP. nqthang@math.ac.vn Introduction. In [T1] [T4] we have proved some results on Corestriction principle for connecting maps of non-abelian Galois cohomology of reductive groups over local and global fields. In [T3] there was defined also a concept of Weak Corestriction principle for non-abelian Galois cohomology of such groups over arbitrary fields of charateristic 0. It is apparent and natural to consider similar notions for groups of arithmetical types, i.e., consider group schemes over arithmetical rings. Such a treatment over rings is necessary for various arithmetic considerations. For example, in [X], there ha...
This article carries out the numerical simulation of airflow over three dimensional car models using ANSYS Fluent software. The calculations have been performed by using realizable k-e turbulence model. The external airflow field of the... more
This article carries out the numerical simulation of airflow over three dimensional car models using ANSYS Fluent software. The calculations have been performed by using realizable k-e turbulence model. The external airflow field of the simplified BMV M6 model with or without a wing is simulated. Several aerodynamic characteristics such as pressure distribution, velocity contours, velocity vectors, streamlines, turbulence kinetic energy and turbulence dissipation energy are analyzed in this study. The aerodynamic forces acting on the car model is calculated and compared with other authors.
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In the 21st century, mankind has witnessed the rapidly development of all industries with a lot of new products in a variety of types and designs. However, this development has been also causing many problems with the society and the... more
In the 21st century, mankind has witnessed the rapidly development of all industries with a lot of new products in a variety of types and designs. However, this development has been also causing many problems with the society and the ecological environment such as a wasteful excess of products, exhaustive exploitation of natural resources, indiscriminate deforestation, and waste pollution affecting the living environment, ecosystem, and human health. Many organizations and governments are calling for environmental protection, limit waste emissions, and find good solutions to use the recycled materials as raw materials in production plants. This study would like to provide a solution which not only utilizes waste packaging Pinaceae wood for recycling as raw material but also supplies to the market with a green product responding to the durability requirements in fact. Pinaceae wood packaging residues were chemically processed through two stages. The amount of lignin extract from Pina...
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A self-similarity approximation model for three-wave resonant interaction in transient backward stimulated Raman scattering (BSRS) was derived. Interestingly, as its asymptotic solution, the train of solitary backward Raman pulse train is... more
A self-similarity approximation model for three-wave resonant interaction in transient backward stimulated Raman scattering (BSRS) was derived. Interestingly, as its asymptotic solution, the train of solitary backward Raman pulse train is possibly formed. This result can be considered as an increment of “single” soliton observed previously [A. Abdolvand et al., Phys. Rev. Lett 103, 183902 (2009)].
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Extracts from Croton kongenis present anticancer activities on various cancers. However, there is no research conducted to investigate the effects of Croton kongenis extracts on cervical cancer as well as on zebrafish. In this study, we... more
Extracts from Croton kongenis present anticancer activities on various cancers. However, there is no research conducted to investigate the effects of Croton kongenis extracts on cervical cancer as well as on zebrafish. In this study, we demonstrated that Croton kongenis ethanol extract expressed high toxicity to cervical cancer Hela cells with an IC50 dose of 20.4 µg/mL and to zebrafish embryos with malformations, lethality and hatching inhibition at 72-hpf at effective dose of 125 µg/mL. Interestingly, treatment with Croton kongenis ethanol extract caused cell-cycle-arrest at the G2 phase. Particularly, percentages of Croton kongenis ethanol extract-treated cells in G1, S, G2/M were 70%, 6% and 23%, while percentages of control cells in G1, S, G2/M were 65%, 15% and 18%, respectively. Consistent with cell-cycle-arrest, the expressions of CDKN1A, CDNK2A and p53 in Croton kongenis ethanol extract-treated cells were up-regulated 2.0-, 1.65- and 1.8-fold, respectively. Significantly, t...
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A framework was developed to elucidate (1) the drivers of land degradation, (2) pressures, (3) local impacts and vulnerabilities and (4) adaptation strategies. The combination of participatory approaches, statistical data analysis, time... more
A framework was developed to elucidate (1) the drivers of land degradation, (2) pressures, (3) local impacts and vulnerabilities and (4) adaptation strategies. The combination of participatory approaches, statistical data analysis, time series Landsat imagery and spatial data mining was tested in southeast Vietnam where the impacts of land degradation on the environment and economy are considerable. The major drivers of land degradation are climate, notably drought, and population density. The pressures include natural resource management and land use/cover change. A Landsat archive analysis showed an increase in agricultural land use from 31% to 50%, mostly at the expense of forests, from 1990 to 2019. Farmers adapted by investing in the irrigation of rice and dragon fruit, and by selecting their rainfed crops in line with the changing environment. The most vulnerable were the rural poor and farmers without access to land and water resources. The best protection against land degrad...
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In this study, we showed that crude extract of Anisomeles indica (AI-EtE) expressed its toxicity to HeLa cells with an IC50 dose of 38.8 µg/mL and to zebrafish embryos with malformations, lethality and hatching inhibition at 72-hpf at... more
In this study, we showed that crude extract of Anisomeles indica (AI-EtE) expressed its toxicity to HeLa cells with an IC50 dose of 38.8 µg/mL and to zebrafish embryos with malformations, lethality and hatching inhibition at 72-hpf at doses higher than 75 µg/mL. More interestingly, flow cytometry revealed that AI-EtE significantly promoted the number of cells entering apoptotic. Accordingly, the transcript levels of BAX, CASPASE-8, and CASPASE-3 in the cells treated with AI-EtE at IC50 dose were 1.55-, 1.62-, and 2.45-fold higher than those in the control cells, respectively. Moreover, treatment with AI-EtE caused cell cycle arrest at the G1 phase in a p53-independent manner. Particularly, percentages of AI-EtE-treated cells in G1, S, G2/M were, respectively 85%, 6.7% and 6.4%; while percentages of control cells in G1, S, G2/M were 64%, 15% and 19%, respectively. Consistent with cell cycle arrest, the expressions of CDKN1A and CDNK2A in AI-EtE-treated cells were up-regulated 1.9- an...
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In the study of fluid flows, one of the important parameters is the spatial-temporal velocity distribution. Experimental measurement of the parameter is required for the development and validation of various models in this field.... more
In the study of fluid flows, one of the important parameters is the spatial-temporal velocity distribution. Experimental measurement of the parameter is required for the development and validation of various models in this field. Techniques for the measurement of flow velocity at single points have been in operation with great success for many years. However, there are situations where the measured data at one point is obviously not enough to understand structures in, e.g., turbulent/transient flows. One of the well-established and powerful methods for measuring velocity distribution is the UVP - Ultrasonic Velocity Profile method that enables measurements of the instantaneous velocity profile along a measurement line, i.e. the sound path. The new application of spike excitation along with the Doppler signal processing to the UVP method has recently been successfully tested. Regarding this new method, factors influencing the measurement result require further careful investigations....
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In this paper, a new nonlinear double-arm optical tweezer combining Mach-Zenhder interferometer, objective lens and organic dye layer is proposed. Based on the ray-optical and wave optical approximations, the expression describing the... more
In this paper, a new nonlinear double-arm optical tweezer combining Mach-Zenhder interferometer, objective lens and organic dye layer is proposed. Based on the ray-optical and wave optical approximations, the expression describing the separation of two trap centers and laser intensity distribution is derived. The obtained results show that the separation between two trap centers, the laser intensity distribution, trap region's area and optical trap efficiency can be controlled by tuning laser power. The proposed model is seen to be a double-arm optical tweezer for controlling 3D microsphere by optical method.
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We introduce the concept of epidemic-fitted wavelets which comprise, in particular, as special cases the number I(t) of infectious individuals at time t in classical SIR models and their derivatives. We present a novel method for... more
We introduce the concept of epidemic-fitted wavelets which comprise, in particular, as special cases the number I(t) of infectious individuals at time t in classical SIR models and their derivatives. We present a novel method for modelling epidemic dynamics by a model selection method using wavelet theory and, for its applications, machine learning-based curve fitting techniques. Our universal models are functions that are finite linear combinations of epidemic-fitted wavelets. We apply our method by modelling and forecasting, based on the Johns Hopkins University dataset, the spread of the current Covid-19 (SARS-CoV-2) epidemic in France, Germany, Italy and the Czech Republic, as well as in the US federal states New York and Florida.