HPU2 Journal of Science: Natural Sciences and Technology

Algebraic dependences of meromorphic mappings sharing few moving hyperplanes with truncated multiplicity

Huong-Giang Ha — Fri, 26 Apr 2024 00:00:00 +0700

In this article, we will prove an algebraic dependence theorem for meromorphic mappings into a complex projective space sharing few moving hyperplanes with different truncated multiplicity. Moreover, we also consider the weaker condition: \[\nu _{(f,{a_i}), \le k_i}\le \nu _{(g,{a_i}), \le k_i} \text{ instead of } \nu _{(f,{a_i}), \le k_i}= \nu_{(g,{a_i}), \le k_i}\] for some moving hyperplanes among the given moving hyperplanes. In order to implement this, besides using the technique reported by S. D. Quang in (Two meromorphic mappings having the same inverse images of some moving hyperplanes with truncated multiplicity, Rocky Mountain J. Math., vol. 52, no. 1, pp. 263–273, 2022) we have to separate the 2n + 2 moving hyperplanes from the given p+1 moving hyperplanes. After that, we count multiples of the intersection of the inverse images of the mappings f and g sharing these moving hyperplanes. Our result is an improvement of many previous results in this topic.

A method for growing and differentiating the C2C12 muscle cell line in the laboratory

Ngoc - Hoan Le, Dinh-Toi Chu, Rina Yu — Fri, 26 Apr 2024 00:00:00 +0700

Skeletal muscle-related studies have recently been applied in the combat of obesity and metabolic disorders. Culture skeletal muscle cells in in vitro plays an important role in being a promising model for those researches. In the present study, the C2C12 skeletal muscle cells were grown and differentiated in in vitro. The C2C12 myoblasts were grown in Dulbecco’s modified eagle’s medium (DMEM) containing 10% fetal bovine serum (FBS) for 4 – 5 days. The cells then reached confluent about 70% to 100% and the medium was shifted to DMEM plus 2% horse serum which leads the grown C2C12 cells becoming to differentiated myotubes. Myogenin mRNA levels were found to be significantly higher in the differentiated myotubes than those in the growing cells confirming the successful formation of the differentiated C2C12 cells. These results indicate that the C2C12 cell line is suitable for culture in in vitro to mimic a skeletal muscle microenvironment for further investigations.

Time series analysis and applications in data analysis, forecasting and prediction

Le-Hang Le — Fri, 26 Apr 2024 00:00:00 +0700

Time series analysis is an essential field in data analysis, particularly within forecasting and prediction domains. Researching and building time series models play a crucial role in understanding and predicting the temporal dynamics of various phenomena. In mathematics, time series data is defined as data points indexed in chronological order and have a consistent time interval between consecutive observations. This can include data such as daily stock prices, annual national income, quarterly company revenue, and more. The advantage of time series data is that it can capture the state of a variable over time. In contrast, the world is constantly changing, and phenomena rarely remain static they typically exhibit variations over time. Therefore, time series data has highly practical applications and is used in various fields, including statistics, econometrics, financial mathematics, weather forecasting, earthquake prediction, electroencephalography, control engineering, astronomy, telecommunications, and signal processing. ARIMA, which stands for Auto Regressive Integrated Moving Average, is a widely used time series forecasting method in data science. It is a popular model for analyzing and predicting time-dependent data points. ARIMA combines autoregression, differencing, and moving averages to capture different aspects of time series data. In this paper, we study ARIMA, which is a significant model for analyzing and predicting time series data.

Smart contract: Revolutionizing transactions in the digital age

Thi-Nhung Nguyen — Fri, 26 Apr 2024 00:00:00 +0700

Blockchain technology is a revolutionary concept that has transformed various industries, offering decentralized and secure solutions for data management. At its core, a blockchain is a distributed and immutable ledger that records transactions across a network of computers. One of the key features of blockchain is its transparency, as each participant in the network has access to the same information. The application of blockchain technology extends across diverse sectors, with finance being the most promising and well-known application domain. Cryptocurrencies, like Bitcoin and Ethereum, rely on blockchain to facilitate secure and transparent transactions. The decentralized nature of blockchain eliminates the need for intermediaries, reducing transaction costs and increasing efficiency. Beyond finance, blockchain is making significant strides in supply chain management. The emergence of blockchain technology has paved the way for a transformative innovation in the realm of digital transactions: smart contracts. These self-executing contracts encoded in blockchain have garnered significant attention for their potential to revolutionize the way agreements are made, executed, and enforced. This paper explores the concept of smart contracts, delving into the underlying technology, finding applications across various industries, legal implications, and future prospects.

The origins of size-dependent UV stabilities of CdZnTeS alloyed quantum dots

Fri, 26 Apr 2024 00:00:00 +0700

CdTe-based quantum dots (QDs) have been used as active materials in various applications, such as sensing, imaging, and light-harvesting devices where the QDs are continuously illuminated by suitable lights. Passivation of CdTe QDs with stable inorganic layers to form core/shell or core/multiple-shell structures has been demonstrated to improve the stabilities of QDs against illumination. However, information related to the UV stability of newly developed CdZnTeS alloyed QDs has not been fully explored yet. Herein, we synthesized CdZnTeS alloyed QDs of different sizes and compared their size-dependent stabilities under UV irradiation. Upon UV exposure the first excitonic peak of QDs blue-shifted, gradually and the relative Cd concentration decreased indicating that QDs were steadily dissolved. We found that the smaller QDs dissolved faster than the larger QDs. By correlating this with the change in the QDs' crystalline structure corroborated by X-ray diffraction studies, we demonstrated that the alloyed structure with a sulfide-rich surface enhances the stabilities of larger QDs. The size-dependent stabilities of alloyed QDs demonstrated here provide information for selecting the right QDs for specific applications.

Exponential stabilization of the class of the switched systems with mixed time varying delays in state and control

Hoai-Nam Hoang, Thi-Hong Duong — Fri, 26 Apr 2024 00:00:00 +0700

This paper presents the problem of exponential stabilization of switched systems with mixed time-varying delays in state and control. Based on the partitioning of the stability state regions into convex cones, a constructive geometric design for switching laws is put forward. By using an improved Lyapunov–Krasovskii functional in combination with matrix knowledge, we design a state feedback controller that guarantees the closed-loop system to be exponentially stable. The obtained conditions are given in terms of linear matrix inequalities (LMIs), which can be effectively decoded in polynomial time by various computational tools such as the LMI tool in MATLAB software. A numerical example is proposed to illustrate the effectiveness of the obtained results.

The one-pot synthesis of photoluminescent polycarbonate based on the pyrolysis of citrate

Fri, 26 Apr 2024 00:00:00 +0700

Photoluminescent composites that are air-stable and water-resistant are important for outdoor applications such as road marking paints, light-converting membranes, fluorescent paints, and security inks. Photoluminescent thermoplastics fulfill all conditions but their preparation methods which are vastly based on mixing pre-synthesized fluorescent dyes and plastic could lead to emission quenching due to dye aggregation or thermal degradation. Herein, we demonstrated a simple method to prepare photoluminescent polycarbonate by thermal extrusion polycarbonate with citric acid and urea. UV-vis absorption and photoluminescent studies indicate that fluorescent carbon materials were formed via pyrolysis of the citrate. The composites exhibit light blue emission and a broad excitation band. The results demonstrated herein offer a cost-effective method to prepare diverse photoluminescent composites for outdoor applications.

Solvability Analysis of high-order Linear Differential-Algebraic Equations with time-varying coefficients

Ha-Phi — Fri, 26 Apr 2024 00:00:00 +0700

In this paper, we study the solvability analysis of arbitrarily high-order linear differential-algebraic equations (DAEs) with time-varying coefficients, using the algebraic-behavior approach. We propose a concept of strangeness-index and construct condensed forms for high-order linear DAEs. We also discuss other structural properties like the existence and uniqueness of a solution, consistency and smoothness requirements for an initial vector and for an inhomogeneity. Our work extends the algebraic approach for DAEs and combines this approach with the behavior approach to establish a reformulation algorithm that reveals an underlying ordinary differential equation (ODE) and all hidden constraints in the DAE. This direct treatment of the system addresses the limitations of the classical approach to transforming the system into a first-order DAE. We illustrate our theoretical results with applications in mechanical systems and electrical circuits. This comprehensive study into general high-order systems is a natural progression from the extensive study of first and second-order DAEs.

Investigation of structural and electronic properties of ZnO using first principle calculations

Quoc-Van Duong — Fri, 26 Apr 2024 00:00:00 +0700

In this research, first-principle calculations have been performed to study the geometry structure and electronic properties of ZnO. All possible exchange-correlation energy functionals were used to perform geometry optimization of ZnO in order to find the efficient calculation conditions. Bandgap energy, density of states (DOS), projected DOS (PDOS); and other properties of ZnO were also calculated and discussed. The calculated band-gap value of ZnO is less than 1.0 eV, much smaller than experimental value of 3.37 eV; while the PDOS results indicate the important roles of O 2p and Zn 3d orbitals in ZnO band structures. The well-known limitation of band-gap value calculations using Density Functional Theory (DFT) was solved by applying Hubbard potential on Zn 3d and O 2p orbitals. A full investigation with Hubbard value varying from 0.5 to 10 eV has been performed and the selected value is 8.0 eV for both Zn 3d and O 2p electrons.

Study on isolating, breeding, and cultivation of Xylaria nigripes (Klotzsch) Cooke

Fri, 26 Apr 2024 00:00:00 +0700

The Xylaria nigripes fungus is one of the medicinal materials that was used in traditional medicine. Extracts from the mycelium and fruiting bodies of the X. nigripes showed protecting cells, preventing DNA damage, and reducing the programmed death cell rate. In this study, the fruiting bodies of the X. nigripes were collected to isolate, propagate in the liquid medium, and then cultured to induce the fruiting body formation in the rice medium. The results showed that the X. nigripes was successfully isolated on PDAY (Potato Dextrose Agar Yeast Extract) medium, and the mycelium and spore of the X. nigripes had unique characteristics of the species. The biomass of X. nigripes grew well in a liquid nutrient medium containing 20g glucose, 1g MgSO₄.7H₂O, 2g KH₂PO₄, and 5g peptone, reaching the best mass after 21 to 28 days. Using an initial cultured liquid of X. nigripes to culture on rice medium, fruiting bodies were formed and developed after 14 days of culture. This result could potentially be applied to the production of X. nigripes biomass via mycelium and fruit bodies for application in medicine.