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A new ursane-type triterpene, 3β,23,24-trihydroxyurs-12-en-28-oic acid (1), together with eight known compounds (2–9) were isolated from the aerial parts of Ophiorrhiza baviensis. Among them, compounds 2–5 were found for the first time from the genus Ophiorrhiza, while compounds 6–9 were reported from O. baviensis for the first time. Their structures were elucidated by analysis of HR-ESI-MS and NMR (1H-NMR, 13C-NMR, HSQC, and HMBC) spectra, as well as comparison with those reported in the literature. Moreover, all isolated compounds were evaluated for their cytotoxic activities against MCF-7, Hela, KB, A549, and SK-LU-1 cancer cell lines and their effects on LPS-induced NO production in RAW264.7 cells. This is the first report of chemical constituents and biological activities of O. baviensis.

MoS2/rGO composites were synthesized by hydrothermal method from the precursors of MoS2 and reduced graphene oxide (rGO) prepared in the former steps. The influence of the synthesis conditions including hydrothermal temperature and mass ratio of MoS2 to rGO on the structure, morphology, and optical absorption capacity of the MoS2/rGO composites was systematically investigated using physicochemical characterizations. The photocatalytic performance of as-prepared samples was investigated on the degradation of Rhodamine B under visible light, in which, the composites obtained at hydrothermal temperature of 180°C and MoS2/rGO mass ratio of 4/1 exhibited the highest photodegradation efficiency of approx. 80% after 4 hours of reaction. This enhancement in photocatalytic behaviour of composites could be assigned to the positive effect of rGO in life time expansion of photoinduced electrons—holes.

Summary Single-molecule magnets (SMMs) exhibit magnetization blocking in the presence of strong magnetic anisotropy. By employing molecular engineering, the blocking barrier can be significantly modified, remaining independent from other external factors, such as magnetic field. Taking advantage of hyperfine coupling of electronic and nuclear spins further highlights their unique functionality. However, a poor understanding of relaxation mechanisms limits the exploitation of nuclear-spin molecular qubits. Here, we report the first observation of field-dependent oscillation of the magnetization blocking barrier in a holmium metallacrown magnet driven by the switch of relaxation mechanisms involving hyperfine interaction. First-principles calculations reveal an activated temperature dependence of magnetic relaxation, dominated either by incoherent quantum tunneling of magnetization at anti-crossing points or by Orbach-like processes at crossing points. This mechanism demonstrates that these relaxation barriers can be consecutively switched by increasing the external field, which paves a way for manipulating magnetization dynamics of SMMs using hyperfine interaction.

Two efficient and practical approaches are reported for the synthesis of β- and δ-carbolines from 3,4-dibromopyridine. The synthesis is based on site-selective Cu-catalyzed double C–N coupling reactions and subsequent annulations by twofold Pd-catalyzed C–N coupling with amines.

The paper provides a connection between Commutative Algebra and Integer Programming and contains two parts. The first one is devoted to the asymptotic behavior of integer programs with a fixed cost linear functional and the constraint sets consisting of a finite system of linear equations or inequalities with integer coefficients depending linearly on n. An integer $$N_*$$ is determined such that the optima of these integer programs are a quasi-linear function of n for all $$n\ge N_*$$ . Using results in the first part, one can bound in the second part the indices of stability of the Castelnuovo–Mumford regularities of integral closures of powers of a monomial ideal and that of symbolic powers of a square-free monomial ideal.

A new compound, physalucoside A (1), together with seven withanolides (2-8) and three flavonoids (9-11), were isolated from Physalis angulata L. (Solanaceae), a medicinal plant native to Vietnam. The chemical structures of these compounds were elucidated by one- and two-dimensional NMR spectra, high-resolution electrospray ionization mass spectrometry analyses, and chemical reactivity. The anti-inflammatory and cytotoxic activities of isolated compounds were also evaluated. These data suggest that the anti-inflammatory activity of P. angulata is due primarily to its withanolide content. This study demonstrates the potential of withanolides as promising candidates for the development of new anti-inflammatory drugs.

Many chemicals found in mangroves reportedly exhibit potent anticancer, antibacterial, anti-inflammatory, antioxidant, and antitumor properties. Several of such compounds include feature unique structures and display interesting pharmacological effects. Few medicinal mangrove plants from Vietnam have been characterized with regard to their chemical constituents. Aegiceras corniculatum (L.) Blanco is a mangrove shrub that exhibits activity against various types of cancer. To identify new secondary metabolites and determine the source(s) of biological activity in Vietnamese medicinal mangrove plants, the chemical constituents of A. corniculatum were isolated, and their structures were appropriately established using common spectroscopic methods (1D and 2D-NMR, IR, HR-ESI-MS), and by producing derivatives by chemical reactions. Complementarily, it is worth noting, that the anti-inflammatory effects of the isolated compounds were investigated by measuring the production of pro-inflammatory cytokines IL-12 p40, IL-6, and TNF-α in lipopolysaccharide-stimulated bone marrow-derived dendritic cells; in this sense, the target compounds 2 and 3 were potent inhibitors of cytokines TNF-α, IL-6, and IL-12 p40, indicating promising anti-inflammatory effects. Furthermore, compounds 1 and 4 strongly promoted apoptosis of B16F10 melanoma cells. It is convenient to highlight, that the obtained results suggest that saponins from A. corniculatum could be potential candidates for treating cancer and inflammatory illnesses.

The n%Mn-MoS2/rGO (labeled as n%MMS/rGO, where n% = Mn/(Mn + Mo) in mol) composites were successfully prepared by a facile hydrothermal method from the Mn-MoS2 (MMS) and rGO precursors, in which the MMS was obtained by a facile one-step calcination of (NH4)6Mo7O24·4H2O, (NH2)2CS, and Mn(CH3COO)2·4H2O as precursors in N2 gas at 650°C. The samples were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron paramagnetic resonance spectroscopy (EPR), UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), and X-ray photoelectron spectroscopy (XPS), which indicates the composites containing nanosheets of Mn-MoS2 and rGO components. The photocatalytic activities of the n%MMS/rGO composite photocatalysts were evaluated through the photodegradation of rhodamine B (RhB) under the visible light irradiation. The enhancement in the photocatalytic performance of the achieved composites was attributed to the synergic effect of Mn doping and rGO matrix. The investigation of photocatalytic mechanism was also conducted.

In present study, a steam distillation method has been adopted for extraction of the essential oil from Vietnamese lemon (Citrus aurantifolia) peel harvested from Tien Giang Province, Vietnam. Various extraction conditions influencing the oil yield were investigated. The resulting essential oil was evaluated for physico-chemical characteristics and antibacterial activities. The chemic al composition of oil was investigated by GC-MS. The results showed that with grinded lemon peel, a ratio of water and lemon peels of 3:1 (mL/g), extraction time of 90 min at 120 ºC, the highest essential oil yield was attained at 2.1 %. Bioactive components found at high content included limonene (64.90 %), γ-terpinene (13.70 %), β-pinene (11.89 %), α-pinene (2.11 %), β-cymene (1.80 %) and sabinen (1.52 %). The lemon essential oil in this study was found to inhibit five bacteria strains including Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella enterica and Pseudomonas aeruginosa.

A new steroidal saponin, torvoside R (1), was isolated along with torvoside Q (2) and macaoside (3) from dichloromethane soluble-portion of the aerial parts of Solanum torvum. Their chemical structures were elucidated using HRESIMS, 1 D- and 2 D-NMR as well as comparison with those reported in the literature. All isolated compounds (1 − 3) exhibited cytotoxicity against SK-LU-1, HepG2, MCF-7, and T24 cancer cell lines with IC50 values ranging from 14.18 to 89.31 µg/mL.

6:2 fluorotelomer sulfonate (6:2 FtS) is being widely used as a mist suppressant in the chromate (Cr(VI)) plating process. As a result, it is often present alongside Cr(VI) in the chromate plating wastewater (CPW). While the removal of Cr(VI) from CPW has been studied for decades, little attention has been paid to the treatment of 6:2 FtS. In this study, the removal of Cr(VI) and 6:2 FtS by Ga2O3, In2O3, and TiO2 photocatalysts was investigated. In the Ga2O3/UVC system, over 95% of Cr(VI) was reduced into Cr(III) after only 5 min. Simultaneously, 6:2 FtS was degraded into F− and several perfluorocarboxylates. The predominant reactive species responsible for the degradation of 6:2 FtS in the Ga2O3 system were identified to be hVB+ and O2˙−. In addition, it was observed that the presence of Cr(VI) helped accelerate the degradation of 6:2 FtS. This synergy between Cr(VI) and 6:2 FtS was attributable to the scavenging of eCB− by Cr(VI), which retarded the recombination of eCB− and hVB+. The In2O3/UVC system was also capable of removing Cr(VI) and 6:2 FtS, although at significantly slower rates. In contrast, poor removal of 6:2 FtS was achieved with the TiO2/UVC system, because Cr(III) adsorbed on TiO2 and inhibited its reactivity. Based on the results of this study, it is proposed that CPW can be treated by a treatment train that consists of an oxidation–reduction step driven by Ga2O3/UVC, followed by a neutralization step that converts dissolved Cr(III) into Cr(OH)3(S).

Video streams are becoming ubiquitous in smart cities and traffic monitoring. Recent advances in computer vision with deep neural networks enable querying a rich set of visual features from these video streams. However, it is challenging to deploy these queries on edge devices due to the resource intensive nature of the computing operations of this sort. Hence, this paper will demonstrate our approach in pushing these computing operations closer to the video stream sources via autonomous stream fusion agents. These agents will facilitate an edge computing paradigm that enables edge devices to utilize its computing resources to serve federated queries over video streams. Our demonstration shows that edge devices can significantly alleviate the bottleneck of the centralized server in dealing with distributed video streams.

Three new binuclear FeIII–LnIII complexes, with similar structures, have been synthesized using the end-off compartmental proligand, H2valpn, resulting from the Schiff condensation between o-vanillin and 1,3-propylenediamine: [FeIIILnIII(valpn)(hfac)2(OAc)Cl] (Ln = Gd, Tb, Dy; hfac− = hexafluoroacetylacetonate; AcO− = acetate). The metal ions are triply bridged by two phenoxido oxygen atoms and by the acetato ligand (syn–syn bridging mode). Among all these compounds the FeIII–LnIII exchange interaction was found to be ferromagnetic (JFeGd = +1.004(4) cm−1; H = −JSFeSGd). The [FeIIIDyIII] derivative shows field-induced slow relaxation of the magnetization. The interpretation of the magnetic properties for the [FeIIIGdIII], [FeIIITbIII] and [FeIIIDyIII] is done through ab initio calculations. It was concluded that the temperature behavior of the relaxation time in the [FeIIIDyIII] derivative is due to dominant Orbach relaxation processes between states at the opposite sides and opposite heights of the blocking barrier. From this understanding, the relaxation mechanism for similar systems where a transition metal is in exchange coupling with a strong anisotropic lanthanide ion is elucidated, which could provide a strategy to synthesize other binuclear complexes with better magnetic properties.

We generated a novel G-quadruplex (G4)-specific endonuclease by fusing a G4 recognition domain of the RHAU helicase with a cleavage domain of the Fok1 nuclease. The fusion protein can specifically bind a parallel G4 and cleave a double-stranded DNA (dsDNA) next to it. The new endonuclease could be used to detect a G4 in a long dsDNA, providing a useful tool for mapping the formation of G4s in the genome. Ministry of Education (MOE) Accepted version

Rhodomyrtus tomentosa (Ait.) Hassk is a fruit that is gradually becoming popular in Vietnam with superior bioactive compounds. This study aimed to determine the natural anthocyanins from Rhodomyrtus tomentosa (Ait.) Hassk based on extracts and optimized RSM. The Box-Behnken design was shown the influence of the optimal conditions for the MAE procedure are 5.07 min, 206 W and 2.53 g/mL with the optimal anthocyanin content achieved Y = 133.88 mg/L, all reactions are within the threshold of the predicted value. The results are in line with the proposed model for the anthocyanin extraction (R2 = 0.9849).

A phytochemical investigation of Physalis minima led to the isolation of six withanolides, including withanolide E (1), withaperuvin C (2), 4β-hydroxywithanolide E (3), 28-hydroxywithaperuvin C (4), physaperuvin G (5), and 4-deoxywithaperuvin (6). Their chemical structures were elucidated by 1 D-NMR and 2 D-NMR data, as well as comparison with the data reported in the literature. All isolated compounds were evaluated for their cytotoxic activity against HepG2, SK-LU-1, and MCF7 cancer cell lines. As the obtained results, compounds 1 and 3 displayed the strongest cytotoxicity against HepG2, SK-LU-1, and MCF7 cell lines with IC50 value ranging from 0.051 ± 0.004 to 0.86 ± 0.09 μg/mL.

International audience; With an ever-growing population of around 10 million inhabitants (officially 7.9 in 2013), Ho Chi Minh City (HCMC) is set to become one of the largest cities in South East Asia and already occupies a major economic role in the area. To accommodate the increasing population, the megacity now stretches out in an urban continuum covering more than 800 square kilometers and is currently growing at a rate of 3.2% per year. If the neighboring provinces around HCMC are included, the total population reaches nearly 18 million people.This paper attempts to describe the interplay between HCMC and flood-related risks and offer some guidelines to deal with inundations. The potential risks of flooding by rain, tsunami and/or dam failure upstream of the city are evaluated and contextualized within the perspective of climate and human-induced environmental changes. The region is highly vulnerable to the combined effects of subsidence and rising sea levels and has already led to serious flooding that may extend spatially before the end of the century. We propose possible preventative solutions to urban flooding using a multi-pronged approach to issues regarding urban development and suggest a redevelopment strategy for major infrastructure projects.

The modified phonon polariton model is proposed to quantitatively describe the dispersion of collective density oscillations of liquid water in the glass-like regime consisting of the fast and the normal sound modes. The interaction between the local electromagnetic field generated from the collective oscillations of water dipoles and the transverse collective density oscillations leads to the appearance of the two modes. This model is suitable for description of water dynamics from the Frenkel to the Debye frequency where the wavelength of the collective excitations is larger than the mean intermolecular separation at a fixed temperature and pressure. The change in some dynamical parameters of liquid water around the onset point is also pointed out, demonstrating the transformation from the hydrodynamic to the glass-like regime. The terahertz dielectric responses of liquid water are estimated and interpreted, revealing a correlation between electrodynamics and density wave. Moreover, we predict that only the high-energy mode with large wave vector could carry function of propagation of biological information. Our model might extend and apply to study collective density oscillations in the other similar liquid systems.

The essential oil from the leaves of Paramignya trimera (Oliv.) Guillaum was obtained by hydrodistillation and analysed by Gas Chromatography-coupled with Mass Spectrometry (GC/MS) for the first ti...

Estuarine/river engineers often encounter a problem that it is hard to specify an upstream boundary of a delta in the numerical modeling because of lack of good quality discharge data. This...

A series of 5-aryl-5H-pyrido[2',1':2,3]imidazo[4,5-b]indoles was successfully prepared in good yields by a practical four-step strategy. In this procedure, the key step was demonstrated to be the domino Pd-and Cu-catalyzed C–N coupling reactions of 3-bromo-2-(2-bromophenyl)imidazo[1,2-a]pyridine with amines.

SnO2/graphite oxide/g-C3N4 composite was synthesized by hydrothermally growing SnO2 nanosheets on graphite oxide/g-C3N4 using tin dichloride and mercapto acetic acid as tin source and structure-directing agent for SnO2 nanosheets, respectively. For comparison, SnO2/graphite oxide and SnO2/g-C3N4 composites were prepared with the same procedure except different supports. The obtained composites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric-differential thermal analysis and electrochemical properties. The results show that the SnO2/graphite oxide/g-C3N4 composite with the graphite oxide/g-C3N4 support enhanced reversible capacity and cycling performance for lithium storage.

In this study, Ag/Zn2TiO4 powder with uniform size (

Essential oils from the leaf and twig of Polyalthia suberosa (Roxb.) Thwaites were analyzed using GC/MS/FID. A total of sixty-three constituents were namely identified accounting for 96.03 and 94.12 % in the hydrodistilled oils of the leaf and twig, respectively. Monoterpenes, monoterpenoids, sesquiterpenes, and sesquiterpenoids were characteristic derivatives of P. suberosa essential oils. Sesquiterpenes bicyclogermacrene (26.26 %) and (E)-caryophyllene (7.79 %), and monoterpene β-pinene (12.71 %) were the major constituents of the leaf oil. Sesquiterpenes (E)-caryophyllene (17.17 %) and α-humulene (9.55 %), sesquiterpenoid caryophyllene oxide (9.41 %), and monoterpenes camphene (8.16 %) and tricyclene (6.35 %) were to be main components in the twig oil. The leaf oil indicated cytotoxic activity against three cancer cell lines HepG2, MCF7 and A549 with the IC50 values of 60.96-69.93 μg/mL, while the twig oil inhibited MCF7 with the IC50 value of 66.70 μg/mL. Additionally, the twig oil successfully suppressed the growth of the negative Gram bacterium Pseudomonas aeruginosa, fungus Aspergillus niger, and yeast Candida albicans with the same MIC value of 50 μg/mL, whereas the leaf oil had the same result on the negative Gram bacterium Escherichia coli.

The COVID-19 pandemic has caused a drastic change in traffic in the U.S and throughout the world. With the drop in traffic volume, the fuel consumption used for traveling should decline. This study focuses on the changes in fuel consumption of public transportation before and during the pandemic. The fuel consumption volumes of diesel bus fleet in Chattanooga were analyzed to identify the changes between the two periods. Our study provides preparation for future disasters.

International audience; Three new flavone 6-C-glycosides, amesiflavones A-C (1-3) together with four known compounds, (+)-aptosimon (4), (+)-isolariciresinol (5), cleomiscosin A (6), and cleomiscosin C (7) were isolated from the leaves of Amesiodendron chinense (Merr.) Hu. Their structures were elucidated by spectroscopic methods, including 1D-, 2D-NMR and MS spectra and comparing with those reported in the literature. All compounds were evaluated for cytotoxic activities against five human cancer cell lines, KB, SK-LU-1, MCF-7, HepG-2, and SW-480. As the results, compounds 1, 2, 4, 6, and 7 showed weak activity on all tested human cancer cell lines with IC50 values ranging from 71.0 to 146.0 µM.

One of the biggest issues in electrocoagulation (EC) water treatment processes is electrode fouling, which can cause decreased coagulant production, increased ohmic resistance and energy consumption, and reduced contaminant removal efficiency, among other operational problems. While it has been suggested that switching the current direction intermittently (i.e., polarity reversal, PR) can help mitigate electrode fouling, conflicting results about the utility of this approach have been reported in the literature. The objective of this study was to systematically investigate the effects of PR frequency and current density on the performance of Fe-EC and Al-EC. It was found that operating Fe-EC under the PR mode reduced neither electrode fouling nor energy consumption. Notably, the Faradaic efficiency (ϕ) in Fe-EC decreased with increasing PR frequency; ϕ was as low as 10% when a PR frequency of 0.5 minutes was employed. Unlike Fe-EC, operating Al-EC under the PR mode resulted in high coagulant production efficiencies, reduced energy consumption, and diminished electrode fouling. In addition to comparing PR-EC and DC-EC, a novel strategy to minimize electrode fouling was investigated. This strategy involved operating Fe DC-EC and Al DC-EC with a Ti-IrO2 cathode, whose fouling by Ca- and Mg-containing minerals could be readily avoided by periodically switching the current direction.

Iron immobilized on supports such as silica, alumina, titanium oxide, and zeolite can activate hydrogen peroxide (H2O2) into strong oxidants. However, the role of the support and the nature of the ...

Stauntonia hexaphylla (Lardizabalaceae) has been used as a traditional herbal medicine in Korea and China for its anti-inflammatory and analgesic properties. As part of a bioprospecting program aimed at the discovery of new bioactive compounds from Korean medicinal plants, a phytochemical study of S. hexaphylla leaves was carried out leading to isolation of two oleanane-type triterpene saponins, 3-O-[β-D-glucopyranosyl (1→2)-α-L-arabinopyranosyl] oleanolic acid-28-O-[β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl] ester (1) and 3-O-α-L-arabinopyranosyl oleanolic acid-28-O-[β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl] ester (2). Their structures were established unambiguously by spectroscopic methods such as one- and two-dimensional nuclear magnetic resonance and infrared spectroscopies, high-resolution electrospray ionization mass spectrometry and chemical reactions. Their anti-inflammatory activities were examined for the first time with an animal model for the macrophage-mediated inflammatory response as well as a cell-based assay using an established macrophage cell line (RAW 264.7) in vitro. Together, it was concluded that the saponin constituents, when they were orally administered, exerted much more potent activities in vivo than their sapogenin core even though both the saponins and the sapogenin molecule inhibited the RAW 264.7 cell activation comparably well in vitro. These results imply that saponins from S. hexaphylla leaves have a definite advantage in the development of oral medications for the control of inflammatory responses.

Phytochemical investigation of a methanolic extract of Sedum sarmentosum collected from Vietnam resulted in the isolation of a new megastigmane glucoside, named sedumoside K (1), together with 17 previously reported compounds (2–18). Structural elucidation of the new compound was achieved by HRFABMS, NMR spectroscopic analysis, acid hydrolysis and quantum ECD calculations. The absolute configuration of compounds 2–6 has been revised. The major isolates were tested for cytotoxic activity against HeLa human cervical cancer cells, and all showed moderate activities.

The wide adoption of increasingly cheap and computationally powerful single-board computers, has triggered the emergence of new paradigms for collaborative data processing among IoT devices. Motivated by the billions of ARM chips having been shipped as IoT gateways so far, our paper proposes a novel continuous federation approach that uses RDF Stream Processing (RSP) engines as autonomous processing agents. These agents can coordinate their resources to distribute processing pipelines by delegating partial workloads to their peers via subscribing continuous queries. Our empirical study in “cooperative sensing” scenarios with resourceful experiments on a cluster of Raspberry Pi nodes shows that the scalability can be significantly improved by adding more autonomous agents to a network of edge devices on demand. The findings open several new interesting follow-up research challenges in enabling semantic interoperability for the edge computing paradigm.

A comprehensive phytochemical investigation of the dichloromethane-soluble fraction of Physalis angulata led to the isolation of eight compounds (1–8) including two new withanolides named physagulin P and Q (compounds 5 and 8). Their chemical structures were established using two-dimensional nuclear magnetic resonance (spectroscopy. The cytotoxic activity of these metabolites was investigated against A549, HeLa, and PANC-1 cancer cell lines. Among them, compound 1 showed significant cytotoxic activity against A549 cells with a half-maximal inhibitory concentration (IC50) value of 8.27 μM, while compound 7 showed the most potent activity against PANC-1 cells with an IC50 value of 3.18 μM.

This review critically examined the existing technologies for the treatment of sulfolane, which is an emerging groundwater contaminant. In general, sulfolane plumes are difficult to contain and mitigate because sulfolane is highly mobile and does not biodegrade to an appreciable extent under anoxic conditions typical of many subsurface environments. Several studies have shown that sulfolane biodegradation can be enhanced in the presence of oxygen, suggesting that in situ biosparging or ex-situ (i.e., pump and treat) aerobic biodegradation can potentially be effective means of remediating sulfolane-contaminated sites. While highly reactive species such as SO4•- and •OH radicals have been shown to oxidize sulfolane, whether sulfolane can be effectively treated by ex situ advanced oxidation processes (AOPs) or by in situ chemical oxidation (ISCO) needs to be further examined. Besides chemical and biological treatments, pump and treat by adsorption on granular activated carbon (GAC) has been applied to remove sulfolane at several sites. To optimize the treatment as well as to identify more effective adsorbents, additional research is needed to investigate the mechanism and factors affecting sulfolane adsorption. In addition to assessing the treatment of sulfolane, this review also discussed the analytical methods for the quantification of sulfolane in the context that guidelines for sulfolane will likely become more stringent and, therefore, analytical methods with lower detection limit will be needed for future research.

In this work, the isomeric ratio of 152m1Eu(8−)–152m2Eu(0−) produced from the 153Eu(γ, n)152Eu reaction have been measured in the whole giant dipole resonance region by the activation method. In order to improve the accuracy of the experimental results, the necessary corrections were made in the gamma activity measurements and data analysis. The results were discussed and compared with the similar data from literature to examine the excitation energy, the spin difference and the nuclear reaction channel effects and can be used for the interpretation on the structure of the nucleus and the mechanisms of nuclear reactions. The data for bremsstrahlung end-point energies of 19–23 MeV are first-time measurements.

Hypericum sampsonii is an important medicinal plant used in Vietnam to treat many diseases such as backache, burns, diarrhea, and swelling. In order to study the chemical constituents in the aerial...

Electrocoagulation (EC) is a promising electrochemical water treatment technology. However, a major challenge to sustaining effective long-term EC operation is controlling the precipitation of materials on the electrodes, commonly referred to as fouling. Periodically reversing electrode polarity has been suggested as an in-situ fouling mitigation strategy and is often implemented in EC field applications. However, the utility of this approach has not been investigated in detail. In this study, the effect of polarity reversal (PR) on the performance of EC using iron electrodes was examined under different water chemistry conditions and at a range of reversal frequencies. It was observed that the faradaic efficiency in PR-EC was always lower than that in the EC systems operated with a direct current (i.e., DC-EC). It was also observed that the faradaic efficiency progressively decreased as the current reversal frequency increased, with the faradaic efficiency dropping as low as 10% when the PR interval was 0.5 min. Results from fouling layer, chronopotentiometric, and cyclic voltammetric investigations indicated that the decrease in the faradaic efficiency was caused by (i) increased electrode fouling by iron precipitates and (ii) electrochemical side reactions at the electrode-electrolyte interface. The extent of these effects was dependent on the solution chemistry; oxyanions and sulfide were found to be particularly detrimental to the performance of PR-EC, causing severe electrode fouling while decreasing the faradaic efficiency. Fouling could be mitigated by increasing the solution convection rate, resulting in a shear on the electrode surface that removed iron and other electrochemically reactive species from the electrodes.

The bitter melon, Momordica charantia L., was once an important food and medicinal herb. Various studies have focused on the potential treatment of stomach disease with M. charantia and on its anti-diabetic properties. However, very little is known about the specific compounds responsible for its anti-inflammatory activities. In addition, the in vitro inhibitory effect of M. charantia on pro-inflammatory cytokine production by lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) has not been reported. Phytochemical investigation of M. charantia fruit led to the isolation of 15 compounds (1−15). Their chemical structures were elucidated spectroscopically (one- and two-dimensional nuclear magnetic resonance) and with electrospray ionization mass spectrometry. The anti-inflammatory effects of the isolated compounds were evaluated by measuring the production of the pro-inflammatory cytokines interleukin IL-6, IL-12 p40, and tumor necrosis factor α (TNF-α) in LPS-stimulated BMDCs. The cucurbitanes were potent inhibitors of the cytokines TNF-α, IL-6, and IL-12 p40, indicating promising anti-inflammatory effects. Based on these studies and in silico simulations, we determined that the ligand likely docked in the receptors. These results suggest that cucurbitanes from M. charantia are potential candidates for treating inflammatory diseases.

The title compound, C25H27NO4(I), the product of the unusual thermolysis of azacyclic allene methyl 10,11-dimethoxy-3,8-dimethyl-6-phenyl-3-azabenzo[d]cyclodeca-4,6,7-triene-5-carboxylate, represents a bicyclic heterosystem and crystallizes in the monoclinic space groupP21/cwith three crystallographically independent molecules in the unit cell. These independent molecules adopt very similar geometries and differ only in the conformations of the two methoxy substituents on the benzene ring. In two of the three independent molecules, both methoxy groups are almost coplanar with the benzene ring [the C—C—O—Me torsion angles are 10.8 (2), 12.3 (2), 9.1 (2) and 13.6 (3)°], whereas in the third molecule, one of the methoxy groups is practically coplanar to and the other methoxy group is roughly perpendicular to the benzene ring, the C—C—O—Me torsion angles being 14.1 (2) and 76.5 (2)°. The molecule of (I) comprises a fused tetracyclic system containing two five-membered rings (cyclopentenes) and two six-membered rings (piperidine and benzene). The five-membered rings have the usual envelope conformation, with the methyl-subsituted C atom as the flap in each molecule, and the six-membered piperidine ring has a chair conformation. The methyl substituent at the N atom occupies the sterically favourable equatorial position. The carboxylate group lies almost within the basal plane of the parent cyclopentene ring [making dihedral angle of 11.68 (8), 18.94 (9) and 15.16 (9)° in the three independent molecules], while the phenyl substituent is twisted by 48.26 (6), 42.04 (6) and 41.28 (6)° (for the three independent molecules) relative to this plane. In the crystal, molecules of (I) form stacks along theb-axis direction. The molecules are arranged at van der Waals distances.

Let I be a monomial ideal in a polynomial ring $R = k[x_{1},\dots ,x_{r}]$ . In this paper, we give an upper bound on $\overline {\text {dstab}} (I)$ in terms of r and the maximal generating degree d(I) of I such that $\text {depth} R/\overline {I^{n}}$ is constant for all $n\geqslant \overline {\text {dstab}}(I)$ . As an application, we classify the class of monomial ideals I such that $\overline {I^{n}}$ is Cohen-Macaulay for some integer n ≫ 0.

One of the experimental programs that will be carried out at the Extreme Light Infrastructure – Nuclear Physics (ELI-NP) facility is the production of exotic neutron-rich ion beams in an IGISOL facility via photofission in a stack of actinide targets placed at the center of a cell filled with He gas. Simulations with the Geant4 toolkit were done for the optimization of the target configuration that maximizes the rate of released photofission fragments. The cell geometry is established based on the stopping properties of these fragments. Studies, based on simulations with Geant4 and SIMION 8.1, of the space charge effect and its induced electric field in the gas cell are presented. Estimates of the extraction time and efficiency of the photofission fragments are derived.

Ordered CoNiP nanowire arrays with average diameter of 200 nm have been fabricated by electrodeposition into polycarbonate templates at different pH levels. X-ray diffraction analysis and high-resolution transmission electron microscopy confirmed the quality of the fabricated nanowires. Magnetic measurements revealed that the magnetic anisotropy of the nanowires was significantly altered by varying the pH level of the electrolytic bath. With increasing pH level, the coercive field (Hc) and the remanent to saturation magnetization ratio (Mr/Ms) rapidly increased in the pH range of 2.0 to 3.5 and tended to saturate for higher levels of pH. The CoNiP nanowires were found to transform from soft- to hard-magnetic characteristics when the pH level exceeded a critical value of ∼3.5, at which the maximum coercivity of 1430 Oe was achieved.

We give a bound for n 0 ( I ) from which the depth function depth R / I ( n ) of the quotient ring by symbolic powers of a squarefree monomial ideal I stabilizes. In the unmixed codimension two case we show that depth R / I ( n ) is a non-increasing function of n and use this property to provide a sharp bound for n 0 ( I ) .

Chemical investigation of an acidic methanol extract of the whole plants of Datura metel resulted in the isolation of two new guainane sesquiterpenes, 1β,5α,7β-guaiane-4β,10α,11-triol ( 1 ) and 1α,5α,7α-11-guaiene-2α,3β,4α,10α,13-pentaol ( 2 ), along with eight known compounds: pterodontriol B ( 3 ), disciferitriol ( 4 ), scopolamine ( 5 ), kaempferol 3- O -β- d -glucosyl(1 → 2)-β- d -galactoside 7- O -β- d -glucoside ( 6 ), kaempferol 3-O-β-glucopyranosyl(1 → 2)-β-glucopyranoside-7-O-α-rhamnopyranoside ( 7 ), pinoresinol 4′′- O - β - d -glucopyranoside ( 8 ), (7 R ,8 S ,7′ S ,8′ R )-4,9,4′,7′-tetrahydroxy-3,3′-dimethoxy-7,9′-epoxy-lignan-4- O -β- d -glucopyranoside ( 9 ), and (7 S ,8 R ,7′ S ,8′ S )-4,9,4′,7′-tetrahydroxy-3,3′-dimethoxy-7,9′-epoxylignan-4- O -β- d -glucopyranoside ( 10 ). Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D NMR and MS spectra. Compounds 2 - 4 and 6 - 10 were shown to have modest anti-inflammatory effects through inhibition of NO production in LPS-stimulated BV cells.

Two new naphtoquinones (smenocerones A and B, 1 and 2) and four known sesquiterpene cyclopentenones (dactylospongenones A-D, 3-6) were isolated from sponge Smenospongia cerebriformis living in the Eastern Sea of Vietnam. Their chemical structures were determined by high resolution electrospray ionization (HR-ESI)-MS, NMR spectroscopic analysis, and in comparison with the reported data. The chiroptical properties of compounds 3-6 were examined by experiment and theoretical calculation of circular dichroism (CD) spectra to prove their absolute configurations. Compound 2 significantly exhibited cytotoxic activity towards lung carcinoma (LU-1), hepatocellular carcinoma (HepG-2), promyelocytic leukemia (HL-60), breast carcinoma (MCF-7), and melanoma (SK-Mel-2) human cancer cells with IC50 values of 5.5±0.8, 3.2±0.2, 4.0±0.7, 4.1±0.8, and 5.7±1.1 µg/mL, respectively.

The nanocomposite of metallic nickel and nickel oxide (denoted as Ni–NiO), synthesized by a simple sol–gel method, was found to activate peroxydisulfate (PDS), resulting in the effective oxidation of phenolic compounds and selected pharmaceuticals. A nonradical mechanism was proposed to explain the activation of PDS by Ni–NiO, in which organic contaminants are believed to be oxidized through an electron abstraction pathway mediated by the reactive complexes formed between PDS and the Ni–NiO surface. This mechanism was supported by multiple lines of evidence including radical scavenger experiments, the oxidation products, linear sweep voltammetry, and electron paramagnetic resonance spectroscopy. The Ni–NiO/PDS system exhibited a PDS utilization efficiency (expressed by the ratio of degraded organic contaminant to decomposed PDS) that was over 80%, and Ni–NiO showed a greater activity for PDS activation than a commercial nanoparticulate nickel oxide. This improved performance of Ni‒NiO was attributed to the disproportioned incorporation of the metallic Ni into the NiO matrix, creating more sites with oxygen vacancy. Also owing to the metallic Ni, Ni–NiO possessed magnetic properties and therefore could be easily separated and reused.

The oxidation of chlorendic acid (CA), a polychlorinated recalcitrant contaminant, by heat-, mineral-, and base-activated persulfate was investigated. In pH 3–12 homogeneous (i.e., solid-free) solutions, CA was oxidized by •OH and SO4•- radicals, resulting in a nearly stoichiometric production of Cl−. The rate constants for the reaction between these radicals and CA were measured at different temperatures by electron pulse radiolysis, and were found to be kOH = (8.71 ± 0.17) × 107 M−1s−1 and kSO4 = (6.57 ± 0.83) × 107 M−1s−1 at 24.5 °C for •OH and SO4•-, respectively. CA was oxidized at much slower rates in solutions containing iron oxyhydroxide or aquifer soils, partially due to the adsorption of CA on these solids. To gain further insight into the effect of solids during in-situ remediation of CA, the adsorption of CA onto iron (hydr)oxide, manganese dioxide, silica, alumina, and aquifer soils was investigated. The fraction of CA that was adsorbed on these materials increased as the solution pH decreased. Given that the solution pH can decrease dramatically in persulfate-based remedial systems, adsorption may reduce the ability of persulfate to oxidize CA. Overall, the results of this study provide important information about how persulfate can be used to remediate CA-contaminated sites. The results also indicate that the groundwater pH and geology of the subsurface can have a significant influence on the mobility of CA.

In this report, overview of the new installed Pelletron 5SDH-2 accelerator at Hanoi University of Science, Vietnam and possibilities for performing astrophysics-related nuclear reactions based on this accelerator will be described. In addition to that, some preliminary simulation results for designing and optimizing the experimental set-up in studying reactions 10B(α, p)13C with projectile energies in the Gamow-window will be shown.