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In future wireless systems beyond 5G and 6G, addressing diverse applications with varying quality requirements is essential. Open radio access network (O-RAN) architectures offer the potential for dynamic resource adaptation based on traffic demands. However, achieving real-time resource orchestration remains a challenge. Simultaneously, digital twin (DT) technology holds promise for testing and analyzing complex systems, offering a unique platform for addressing dynamic operation and automation in D-RAN architectures. Yet, developing DTs for complex 5G/6G networks poses challenges, including data exchanges, ML model training data availability, network dynamics, processing power limitations, interdisciplinary collaboration needs, and lack of standardized methodologies. This article provides an overview of D-RAN architecture, and its trends and challenges, proposing the DT concepts for O-RAN with solution examples showcasing its integration into the framework.

This letter addresses a multivariate optimization problem for linear movable antenna arrays (MAAs). Particularly, the position and beamforming vectors of the under-investigated MAA are optimized simultaneously to maximize the minimum beamforming gain across several intended directions, while ensuring interference levels at various unintended directions remain below specified thresholds. To this end, a swarm-intelligence-based firefly algorithm (FA) is introduced to acquire an effective solution to the optimization problem. Simulation results reveal the superior performance of the proposed FA approach compared to the state-of-the-art approach employing alternating optimization and successive convex approximation. This is attributed to the FA’s effectiveness in handling non-convex multivariate and multimodal optimization problems without resorting approximations.

This paper proposes a generalized Firefly Algorithm (FA) to solve an optimization framework having objective function and constraints as multivariate functions of independent optimization variables. Four representative examples of how the proposed generalized FA can be adopted to solve downlink beamforming problems are shown for a classic transmit beamforming, cognitive beamforming, reconfigurable-intelligent-surfaces-aided (RIS-aided) transmit beamforming, and RIS-aided wireless power transfer (WPT). Complexity analyzes indicate that in large-antenna regimes the proposed FA approaches require less computational complexity than their corresponding interior point methods (IPMs) do, yet demand a higher complexity than the iterative and the successive convex approximation (SCA) approaches do. Simulation results reveal that the proposed FA attains the same global optimal solution as that of the IPM for an optimization problem in cognitive beamforming. On the other hand, the proposed FA approaches outperform the iterative, IPM and SCA in terms of obtaining better solution for optimization problems, respectively, for a classic transmit beamforming, RIS-aided transmit beamforming and RIS-aided WPT.

Magnetic drug targeting has emerged as a promising approach for enhancing the efficiency of drug delivery. Recent developments in real-time monitoring techniques have enabled the guidance of magnetic nanoparticles (MNPs) in the vascular network. Despite recent developments in magnetic navigation, no comprehensive strategy for swarm of nanoparticles steering under fluid flow exists. This paper introduces a strategy for MNPs steering in a vascular network under fluid flow. In the proposed scheme, the swarm of nanoparticles are initially guided to an area that guarantees their successful guidance towards a desired direction (called safe zone) using an asymmetrical field function to handle swarm of nanoparticles. Then, a transporter field function is used to transfer the particles between the safe zones, and finally a sustainer field function is used to keep the particles within the safe zone. A steering algorithm is proposed to enhance the targeting performance in the multi-bifurcation vessel. Utilizing the proposed concept, a high success rate for targeting is achieved in simulations, which demonstrates the potential and limitations of swarm of nanoparticles steering under fluid flow.

This article proposes an elegant optimization framework consisting of a mix of linear-matrix-inequality and second-order-cone constraints. The proposed framework generalizes the semidefinite relaxation (SDR) enabled solution to the typical transmit beamforming problems presented in the form of quadratically constrained quadratic programs (QCQPs) in the literature. It is proved that the optimization problems subsumed under the framework always admit a rank-one optimal solution when they are feasible and their optimal solutions are not trivial. This finding indicates that the relaxation is tight as the optimal solution of the original beamforming QCQP can be straightforwardly obtained from that of the SDR counterpart without any loss of optimality. Four representative examples of transmit beamforming, i.e., transmit beamforming with perfect channel state information (CSI), transmit beamforming with imperfect CSI, chance-constraint approach for imperfect CSI, and reconfigurable-intelligent-surface (RIS) aided beamforming, are shown to demonstrate how the proposed optimization framework can be realized in deriving the SDR counterparts for different beamforming designs.

Phytochemical investigation applying GC (gas chromatography)-MS (mass spectrometry)/GC-FID (flame ionization detection) on the hydro-distilled essential oils of the Vietnamese medicinal plant Uvaria bonianaleaf and twig lead to the detection of 35 constituents (97.36%) in the leaf oil and 52 constituents (98.75%) in the twig oil. Monoterpenes, monoterpenoids, sesquiterpenes, and sesquiterpenoids were characteristic of U. bonianaessential oils. The leaf oil was represented by major components (E)-caryophyllene (16.90%), bicyclogermacrene (15.95%), α-humulene (14.96%), and linalool (12.40%), whereas four compounds α-cadinol (16.16%), epi-α-muurolol (10.19%), α-pinene (11.01%), and β-pinene (8.08%) were the main ones in the twig oil. As compared with the leaf oil, the twig oil was better in antimicrobial activity. With the same MIC value of 40 mg/mL, the twig oil successfully controlled the growth of Gram (+) bacterium Bacillus subtilis, Gram (−) bacterium Escherichia coli, fungus Aspergillus niger, and yeast Saccharomyces cerevisiae. In addition, both two oil samples have induced antiinflammatory activity with the IC50values of 223.7–240.6 mg/mL in NO productive inhibition when BV2 cells had been stimulated by LPS. Docking simulations of four major compounds of U. bonianatwig oil on eight relevant antibacterial targets revealed that epi-α-muurolol and α-cadinol are moderate inhibitors of E. coliDNA gyrase subunit B, penicillin binding protein 2X and penicillin binding protein 3 of Pseudomonas aeruginosawith similar free binding energies of −30.1, −29.3, and −29.3 kJ/mol, respectively. Furthermore, in silicoADMET studies indicated that all four docked compounds have acceptable oral absorption, low metabolism, and appropriated toxicological profile to be considered further as drug candidates.

Background People living with HIV who use drugs (PLHWUD) face enormous challenges to access antiretroviral therapy (ART), addiction treatment, and other healthcare services. This study evaluated the effect of a community capacity-building approach on PLHWUD’s access to healthcare services.Methods A cluster randomized controlled trial was conducted in four provinces of Vietnam. Trained commune health workers in the intervention condition were encouraged to provide services to PLHWUD in the community and engage them in HIV/addiction treatment and care using learned knowledge and skills. A total of 241 PLHWUD participated in surveys at the baseline and every three months for one year. The primary outcome was PLHWUD’s reported barriers to seeking healthcare. A linear mixed-effects regression model with a difference in difference approach was used to estimate the intervention effect on the primary outcome.Results Adjusted analyses indicated that significant intervention effects were observed at the Sixth and ninth month follow-ups for those on ART at the baseline and increased motivation to engage in treatment at the 3-month follow-up (60.2% vs 34.4% for the intervention and control groups, respectively).Conclusions The community capacity-building intervention had shown promising yet limited outcomes among a subset of PLHWUD in the community, that is, PLHWUD who had already initiated ART.

Taking into account imperfect channel state information, this letter formulates and solves a joint active/passive beamforming optimization problem in multiple-input single-output systems with the support of an intelligent reflecting surface. In particular, we introduce an optimization problem to minimize the total transmit power subject to maintaining the users’ signal-to-interference-plus-noise-ratio coverage probability above a predefined target. Due to the presence of probabilistic constraints, the proposed optimization problem is non-convex. To circumvent this issue, we first recast the proposed problem in a convex form by adopting the Bernstein-type inequality, and we then introduce a converging alternating optimization approach to iteratively find the active/passive beamforming vectors. In particular, the transformed robust optimization problem can be effectively solved by using standard interior-point methods. Numerical results demonstrate the effectiveness of jointly optimizing the active/passive beamforming vectors.

ABSTRACTA new species of Billoliviais described from Central Highlands, Vietnam. The new species shows similarities with its congener B. cadamensisand B. poilaneibut differs in several vegetative and reproductive attributes. Hence, we described it here as a new species. A detailed description, distribution, ecology and conservation status along with photographs are provided.

G-quadruplexes (G4s) are reported to present on the SARS-CoV-2 RNA genome and control various viral activities. Specific ligands targeting those viral nucleic acid structures could be investigated as promising detection methods or antiviral reagents to suppress this menacing virus. Herein, we demonstrate the binding between a G4 structure in the RNA of SARS-CoV-2 and a fluorescent probe created by fusing a parallel-G4 specific RHAU53 and a cyan fluorescent protein. The specific binding of G4 in SARS-CoV-2 by RHAU peptide was easily detected under the fluorescence spectrometer. The drawbacks of this approach and potential solutions are also discussed.

ABSTRACTAcranthera hoangiiHareesh & T.A. Le (Rubiaceae) is described as a new species from Vietnam. The new species shows similarities with A. longipes, but shows significant differences in its densely pubescent shoot and petiole, larger flowers, five-nerved calyx lobes and ribbed ovary.

Network slicing is considered to be a crucial feature of fifth generation cellular systems. By dividing the network infrastructure into multiple logical segments, network slicing can support parallel services with different requirements. While technology developments focus on slicing the core networks, there are limited studies in network slicing for radio access networks (RAN). Hence, in this letter, we study the RAN slicing and slice coordination, which is formulated as a bi-convex problem. Even though there are complicated couplings between the RAN resource allocation for each slice and the coordination of the slices that share the same resources, we design two algorithms addressing these couplings of this bi-convex problem. Simulation results validate the efficacy of our proposed algorithms.

Chemical investigation of a fermentation culture of the marine endophytic fungus Paraconiothyriumsp. VK‐13 resulted in the isolation of five compounds, including a new phenolic compound, 1‐(2,5‐dihydroxyphenyl)‐1‐oxobutan‐3‐yl acetate (1) and four known metabolites, 1‐(2,5‐dihydroxyphenyl)‐2‐buten‐1‐one (2), 3,7‐dimethyl‐1,8‐dihydroxy‐6‐methoxyisochroman (3), modiolides A (4) and B (5). Their chemical structures were identified based on 1D, 2D NMR, and MS spectroscopic analysis and comparison with the data reported previously in the literature. All the isolated compounds were reported for the first time from the genus Paraconiothyrium.

Background: Marine sponges have produced a large number of secondary metabolites and become a potent source of anti-cancer agents for drugs discovery. Screening results indicated that methanol extract of the sponge Ircinia echinata significantly induced in vitro antiproliferative effect against human cancer cell strains HepG-2, KB, and MCF-7. Therefore, this study aims to isolate, identify chemical structure, and evaluate antiproliferative activity of constituents from the sponge I. echinata. Methods: Frozen samples of the sponge I. echinata were ultrasonically extracted in methanol. The methanol extract was fractionated and purified using chromatographic methods to obtain pure compounds. Chemical structures of isolated compounds were elucidated by HR-ESI-MS, 1D-, 2D-NMR spectral data, and as well as comparison with reported literature. In addition, antiproliferative effects of isolated compounds on six human cancer cell strains (HepG-2, HL-60, KB, LU-1, MCF-7, and LNCaP) were evaluated by Sulforhodamine B assay. Results: A new furanosesterterpene, 8-hydroxyisovariabilin (1), together with eleven known ones, including four furanoterpenes (2-5), a fatty acid (6), and six sterols (7-12) were isolated from methanol extract of the sponge I. echinata. Antiproliferative evaluation revealed that furanosesterterpene 3 and sterols 7, 9-12 are promising anticancer agents. Among them, sterols 11 and 12 exhibited anti-proliferative effect on tested cancer cell strains with IC50 values in range of 4.53-9.74 μg/mL. Conclusion: The sponge I. echinata found at the sea of Vietnam is a good source for the isolation of furanoterpenoids and sterols. Isolated furanosterterpene (3) and sterols (7, 9-12) are promising antiproliferative agents which could be useful in anticancer drugs discovery.

Using various chromatography methods, five steroids and two brominated lipids (1-7), 3β- hydroxy-5-cholenic acid methyl ester, stigmasta-5,24(28)-dien-3β,29-diol, 24-methylenecholest-4-en- 3β,6β-diol, cholest-5-en-3β,7β-diol, 24-vinylcholest-5-en-3β,24-diol, xestospongiene A, and xestospongiene J, respectively, were isolated from the methanol extract of Vietnamese marine sponge Haliclona oculata (Linnaeus, 1759). Their structures were elucidated by 1D-, 2D-NMR, and ESI-MS spectra and in comparison with those reported in the literature. Compounds 1-4, 6, and 7 were reported from Chalinidae family for the first time. In addition, all compounds were evaluated for eight human cancer cell lines as HepG-2, KB, LU-1, MCF-7, LNCaP, HL- 60, SK-Mel2, and PC-3. As shown in results, compound 2 showed significant cytotoxic activities on KB and LU-1 cancer cell lines with the IC50 values ranging from 8.74 to 9.32 μM.

18 chromone derivatives were designed and synthesized from paeonol. All synthetic compounds were evaluated for their anti-proliferative activity towards eight human cancer cell lines including HepG2, HL-60, KB, LLC, LNCaP, LU-1, MCF7, and SW480. Compounds 3g and 3h presented the best cytotoxic effects towards tested cancer cell lines except HepG2. Their IC50 values were ranging from 7.9±0.4 to 18.9±1.3 μg/mL. Meanwhile, compound 3l showed selective cytotoxicity against MCF7 and KB with IC50 of 13.7±0.6 and 15.5±0.9 μg/mL, respectively.

In this letter, we consider underlay spectrum access in a cognitive radio network, where two coexisting cellular systems, i.e., primary and cognitive, share the same frequency band. The throughput performance of this system is directly linked to the tolerated interference level at the primary receiver. We investigate the fundamental trade-off between the interference tolerance in the primary system and the achievable throughput of the cognitive network. We formulate the network performance as a multi-objective optimization problem with a set of objectives including minimizing the interference imposed on each primary user, and maximizing the intended signal received at every secondary user. We then derive an equivalent standard semi-definite programming form and prove that the derived problem always yields rank-one solutions. The obtained solution set provides the best achievable throughput (characterized by the maximum intended signal power at each cognitive user) for a given level of interference tolerance in the primary system. It also gives the achievable gain on the system throughput if the primary system is able to compromise and increase its interference tolerance, such framework could be a base for negotiations between the operators. An improvement of 0.38 bits/s/channel-use is observed on the achievable throughput for 1 dB higher interference tolerance at the primary receivers.

As the use and availability of qualitative software analysis tools increase, so does ambiguity regarding the choice of the most appropriate software in sport management research. This paper uses NVivo and Leximancer to analyse the same set of data derived from interviews with sport management experts on high performance sport to showcase the differences in findings depending on the type of software used. The findings alert sport management and social science researchers to the importance of closely examining the choice of software for qualitative data analysis. Researchers may base their decision on aspects such as the type and size of data set, their competence and skills in data interpretation and the level of engagement with data analysis they plan on undertaking. This paper discusses the implications for researchers in the sport management field using these tools for data analysis and highlights the value that software can add to the research effort.

Essential oils of two Asteraceae plants Blumea ripariaDC. and Pluchea pteropodaHemsl. ex Hemsl., collected from Vietnam, have been studied by hydro-distillation and GC/MS-FID (gas chromatography/mass spectrometry-flame ionization detector) analysis. Oil yields of B. ripariafresh leaves and twigs were in the range of 0.1–0.2%, whereas essential oil in the fresh aerial parts of P. pteropodareached about 0.5%. Sesquiterpene hydrocarbons and oxygenated sesquiterpenes were the main chemical classes in the essential oils of B. riparia. The leaves and twigs of this species gave essential oils containing germacrene D (33.6-42.6%), (E)-β-caryophyllene (11.2-11.6%), and bicyclogermacrene (9.3-12.1%) as the major components. Oxygenated monoterpenes and sesquiterpene hydrocarbons achieved the highest amounts in the essential oil of P. pteropodaaerial parts; 2,5-dimethoxy-p-cymene (43.5%), β-maaliene (14.0%), and α-isocomene (9.0%) were characteristic compounds. Particularly, as compared with related Blumeaand Plucheaspecies, B. ripariaand P. pteropoda, collected from Vietnam, might be good sources of germacrene D and 2,5-dimethoxy-p-cymene, respectively. The essential oil of B. riparialeaf successfully controlled the growth of the fungus Fusarium oxysporum, with an MIC value of 50.0 µg/mL, and the essential oil of P. pteropodaaerial parts showed significant antimicrobial activity against the Gram positive bacterium Bacillus subtilisand the yeast Candida albicans, with the same MIC value of 50.0 µg/mL.

One of the most important factors influencing the performance of geopolymer composites is the curing temperature. The dependence of geopolymerization process on activator under high temperature is a drawback need to overcome and research. This study focuses on designing of the new and innovative geopolymer composites mixtures designs with an ambient non-curing periods and improving the capacity of this materials, particularly in terms of mechanical properties and impact resistance. Experiments were conducted to measure impact resistance based on ACI committee 544, as well as impact energy absorption, compressive strength, splitting tensile strength, and flexural strength. The experiments were carried out by using fly ash from 20% to 80%, slag from 40% to 60% to replace cement as a main binder, liquid/solid ratios of 0.7–0.8 and 0–1.5% of steel fiber. Comparing with cured-geopolymer composites, the compressive strength, splitting tensile strength, and flexural strength are improved of 18.63%, 30.14%, 10% and non-curing mixture could be applied widely in production and construction site. The liquid/solid material ratio of 0.8 and 1.5% of hooked end steel fiber contribute to the significant enhancement of geopolymer composites without curing. Besides, the experimental result was examined with analysis results using Ansys software showed good agreement with a slight and acceptable difference under 10%, confirming the numerical method can be used to predict test results with acceptable accuracy.

Neuropeptides regulate animal physiology and behavior, making them widely studied targets of functional genetics research. While the field often relies on differential -omics approaches to build hypotheses, no such method exists for neuropeptidomics. It would nonetheless be valuable for studying behaviors suspected to be regulated by neuropeptides, especially when little information is otherwise available. This includes nictation, a phoretic strategy of Caenorhabditis elegansdauers that parallels host-finding strategies of infective juveniles of many pathogenic nematodes. We here developed a targeted peptidomics method for the model organism C. elegansand show that 161 quantified neuropeptides are more abundant in its dauer stage compared with L3 juveniles. Many of these have orthologs in the commercially relevant pathogenic nematode Steinernema carpocapsae, in whose infective juveniles, we identified 126 neuropeptides in total. Through further behavioral genetics experiments, we identify flp-7and flp-11as novel regulators of nictation. Our work advances knowledge on the genetics of nictation behavior and adds comparative neuropeptidomics as a tool to functional genetics workflows.

One new isoflavane, 7,4′-dihydroxy-isoflavanquinone (1), together with ten known compounds (2–11) were isolated from the bark of Dalbergia oliveriPrain. The structures of compounds were determined on the basis of extensive spectroscopic methods, including 1D and 2D NMR and CD spectroscopic data. Using a cell proliferation assay, the isolated compounds were evaluated for their proliferation effects on hair growth. (3R)-5’-Methoxyvestitol (2) and (6aR,11aR)-3,8-dihydroxy-9-methoxypterocarpan (10) significantly increased the proliferation of immortalized dermal papilla cells (iDPC).

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A new ent-kaurane glycoside, annoglabasin H (1), and three known ent-kauranes, annoglabasin E (2), annoglabasin B (3), and 19-nor-ent-kaurent-4-ol-17-oic acid (4) were isolated from the fruits of Annona glabra. Their structures were determined by the combination of spectroscopic and chemical methods, including 1D- and 2D-NMR spectroscopy, as well as by comparison with the NMR data reported in the literature. The cytotoxic activities of these compounds were evaluated on four human cancer cell lines, LU-1, MCF-7, SK-Mel2, and KB. Compound 1exhibited significant cytotoxic activity on all tested human cancer cell lines with IC50values ranging from 3.7 to 4.6 μM.

Four new cucurbitane-typetriterpene glycosides, charantosides D-G (1–4) were isolated from a methanol extract of Momordica charantiafruits. The structures of these compounds were determined by chemical and spectroscopic methods to be (19R)-5β,19-epoxy-25-methoxycucurbita-6,23-diene-3β,19-diol 3-O-β-D-glucopyranoside, (19R)-5β,19-epoxy-25-methoxycucurbita-6,23-diene-3β,19-diol 3-O-β-D-allopyranoside, 7β-methoxycucurbita-5,23E,25-triene-3β-ol 3-O-β-D-allopyranoside, and 3β,7β-dihydroxycucurbita-5,23E,25-triene-19-al 3-O-β-D-allopyranoside.

One new flavonol glycoside, 4′-O-methylmyricitrin 3′-O-β-D-glucopyranoside (1), one new sesquiterpene, reynoudiol (11), as well as the 12 known compounds (2–10, 12–14) quercetin 3-O-methyl ether (2), quercitrin (3), isorhamnetin 3-α-L-rhamnopyranoside (4), tamarixetin 3-α-L-rhamnopyranoside (5), myricitrin (6), 4′-O-methylmyricitrin (7), isorhamnetin 3-O-β-D-xylopyranosyl (1→2)-O-β-D-glucopyranoside (8), isorhamnetin 3-O-β-D-apiofuranosyl-(1→2)-O-β-D-glucopyranoside (9), (+)-catechin (10), 7-drimene-3,11,12-triol (12), clovane-2β,9α-diol (13), and α-cadinol (14), were isolated from the methanol extract of Reynoutria japonicaroots. Based on in vitroscreening of the anti-influenza activity of the isolated compounds, reynoudiol showed significantly higher activity than that of oseltamivir phosphate at the same concentration, and did not induce any detectable cytopathic effect in MDCK cells. The CC50of reynoudiol was above 50 μM and could inhibit influenza virus infection with an IC50of 0.29 ± 0.01 μM. The therapeutic index (TI) of reynoudiol against influenza infection was 172.4, and thus, this compound can be potentially used to treat oseltamivir-resistant influenza virus infection.

One new biscembranoid, petronigrione (1), and five known compounds, methyl tortuoate B (2), lobophytone U (3), lobophytone H (4), (24S)-ergostane 3β,5α,6β,25tetraol-25-monoacetate (5), and (24S)-ergostane-1β,3β,5α,6β,25-pentaol-25-monoacetate (6), were isolated from the methanol extract of the marine sponge Petrosia nigricans.Their structures were established on the basis of spectral and chemical evidence. The cytotoxicity of all compounds was evaluated by MTT assay on four human cancer cell lines, HepG2, KB, LU-1, and MCF-7. Compounds 1 and 2 exhibited moderate cytotoxic activities on the four human cancer cell lines with IC50values ranging of 20.7 - 28.9 μg/mL.

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