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From the leaves of Schefflera sessiliflora De P. V., two new oleanane-type triterpene saponins, named scheffleraside A ( 1 ), scheffleraside B ( 2 ); together with two known saponins, chikusetsusaponin IVa ( 3 ), 3- O -[ α - l -rhamnopyranosyl-(1 → 3)]- β - d -glucuronopyranosyl hederagenin ( 4 ) were isolated by various chromatography methods. Its chemical structure was elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and comparison of their NMR data with previous reported data. [ABSTRACT FROM AUTHOR]

Highlights: [•] Highlight the stratigraphic evolution of Pliocene-Quaternary sediments. [•] Fault systems are mainly oriented in NW-SE and submeridional directions. [•] Quaternary volcanic activities occurred widely, especially near the major faults. [•] High resolution seismic helps identifying 7 sedimentary units. [•] A reworking process during the rapid deglacial transgression at ~ 20-8 ka. [ABSTRACT FROM AUTHOR]

Abstract: Performance evaluation is a crucially important part of designing any mobile ad-hoc wireless networks. For a more comprehensive evaluation, mathematical analysis is essential, along with simulation. In this paper, we present a detailed analytical model for supporting and evaluating the performance of multi-hop paths in mobile ad-hoc wireless networks. More specifically, we show that the performance of multi-hop paths is affected by the stability of individual link and the distribution of hop count of multi-hop paths, and present a closed-form model for packet delivery ratio of multi-hop paths. The analytical model is validated through simulations using various settings of node mobility and network size. [Copyright &y& Elsevier]

Abstract: Objective: The aim of this study is to report the technical details, early outcomes, and lessons learned from laparoscopic repair of 190 cases of choledochal cyst. Method: The operation was performed using 4 ports. The cystic duct was identified and divided. The liver was elevated by 2 stay-sutures: one on the round ligament and the other on the distal cystic duct. The choledochal cyst was isolated and removed completely, and then biliary-digestive continuity was reestablished. Results: From January 2007 to April 2009, 190 patients were operated on. There were 144 girls and 46 boys. Ages ranged from 2 months to 16 years (mean, 46.9 ± 29.3 months). Cyst diameter ranged from 10 to 184 mm. A total of 106 patients were classified as Todani type I cysts, and 84 were type IV. Cystic excision and hepaticoduodenostomy were performed in 133 patients and hepaticojejunostomy in 57 patients. The operating time varied from 70 to 505 minutes (mean, 186 minutes). Conversion to open surgery was required in 2 patients. Intraoperative blood transfusion was required in 4 patients. There were no perioperative deaths. Postoperative anastomotic leakage occurred in 7 patients, resolving spontaneously in 6 and requiring a second operation in 1. Postoperative hospital stay ranged from 5 to 27 days (mean, 7.2 ± 3.3 days). Follow-up occurred between 1 and 24 months postdischarge (mean, 9 ± 2.2 months) and was obtained in 161 patients (84.7%). Of these patients, cholangitis occurred in 4 patients (2.4%). Conclusion: Laparoscopic repair is a safe and effective procedure for choledochal cyst. [Copyright &y& Elsevier]

Abstract: Samples of polyethylene pellets were collected at 30 beaches from 17 countries and analyzed for organochlorine compounds. PCB concentrations in the pellets were highest on US coasts, followed by western Europe and Japan, and were lower in tropical Asia, southern Africa and Australia. This spatial pattern reflected regional differences in the usage of PCBs and was positively correlated with data from Mussel Watch, another monitoring approach. DDTs showed high concentrations on the US west coast and in Vietnam. In Vietnam, DDT was predominant over its metabolites (DDE and DDD), suggesting the principal source may be current usage of the pesticide for malaria control. High concentrations of pesticide HCHs were detected in the pellets from southern Africa, suggesting current usage of the pesticides in southern Africa. This study demonstrates the utility and feasibility of the International Pellet Watch approach to monitor POPs at a global scale. [Copyright &y& Elsevier]

Abstract: In 1996 Khamsi proved a result in hyperconvex metric spaces which is an analogue of the famous KKM-maps principle proved by Ky Fan in 1972 for topological vector spaces. In this note, using the above result due to Khamsi, we establish two results in hyperconvex metric spaces which are analogues of the famous Ky Fan inequality and Sion minimax theorem proved for topological vector spaces in 1972 and 1958, respectively. [Copyright &y& Elsevier]

Long time dynamics of solutions to a strongly coupled system of parabolic equations modeling the competition in bio-reactors with chemotaxis will be studied. If the parameters of the system are periodic, sufficient conditions for positive periodic solutions will be derived in terms of parabolic eigenvalue problems. [Copyright &y& Elsevier]

Abstract: This is the first report of a single trocar nephrectomy for poorly functioning dysplastic kidney and ectopic ureter, performed in 5 patients from 2010 to 2011. The mean operative time was 63 min and mean postoperative hospital stay was 31 h. There were no perioperative complications. The single trocar nephrectomy is a feasible and safe procedure for patients with dysplastic kidney and ectopic ureter. [Copyright &y& Elsevier]

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare, malignant, mesenchymal tumor that is commonly observed in children. The symptoms and imaging characteristics of UESL are not specific and can be mimicked by other tumors or liver abscesses. The tumor often appears as a large, heterogeneous, echoic solid mass with small cystic areas, presenting a cyst-like appearance on computed tomography (CT) and magnetic resonance imaging (MRI). The histopathological manifestations of UESL consist of stellate-shaped and spindle cells scattered on a myxoid background, with high mitotic counts. Cells with multiple or bizarre nuclei can also be observed. Here, we illustrate a 9-year-old male diagnosed with UESL by describing the imaging and histopathological characteristics that resulted in the diagnosis. [ABSTRACT FROM AUTHOR]

• There is a disparity between what is perceived as drivers of deforestation and forest degradation and following proposed measures. • Swidden is seen as a political issue and different interpretations of the problem exist from national, provincial, district, commune to village level. • Actors associated to swidden might be marginalized in REDD+ and PES design and implementation. • REDD+ policies should consider divergent political interests on controversial land uses and their potential of ecosystem services. Swidden cultivation practices have been seen as a major driver of deforestation and forest degradation in Southeast Asia. Using two case studies from Vietnam, this paper examines discourses around swidden practices at multiple levels of governance. Our findings show diverse interpretations of swidden resulting in different policy preferences and policy translations when addressing the issue. At national level, swidden is blamed as a principal driver of deforestation and forest degradation, and as such is a practice to be eliminated. As a result of this national stance, provincial level authorities see the existence of swidden as a failure by which their political performance will be judged. Conversely, swidden communities are seen at district level as an innovative solution to help resource-limited police forces ensure national security in border areas. Local commune and village leaders view swidden as a traditional practice to be respected, so as to maintain harmonious relationships amongst social groups, and avoid ethnic groups protesting against the government. Such differences in discourses and political interests have led to swidden becoming an 'invisible' issue, with government authorities failing to collect and report on data. Not recognizing swidden also means that swidden actors are practically 'forgotten' in the design and implementation of Reducing Emissions from Deforestation and Forest Degradation (REDD+) and Payments for Ecosystem Services (PES). Their omission from forest conservation and management incentive programmes could lead to further social marginalization, and potentially result in deforestation and forest degradation in the area. Our findings suggest that REDD+ policies should take into account diverging political interests on controversial land uses such as swidden cultivation. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To describe the surgical technique, initial results, and overview indications of thoracoscopic repair of congenital diaphragmatic hernia (CDH). Materials and Methods: A retrospective review was undertaken of patients with CDH who underwent thoracoscopic repair by the same surgeon from January 2001 to January 2005. Patients underwent surgery under general anesthesia. Reduction of the hernia contents was carried out using 1 optical trocar and 2 operating trocars. Pleural insufflation with carbon dioxide was maintained at a pressure of 2 to 4 mm Hg. The hernia defect was repaired using nonabsorbable interrupted sutures with extracorporeal knots. Results: There were 45 patients, including 29 boys and 16 girls. Among 19 newborn patients, there were 13 patients younger than 7 days. The other 26 patients were infants and elders. The hernia was located in the left side in 37 patients and in the right side in 8 patients. The mean operative time was 54 minutes. Conversion was required in 4 patients. There were no complications. However, there were 2 postoperative deaths. Conclusions: Thoracoscopic repair is feasible and safe for children with CDH, including selective newborn. The technique causes minimal trauma, results in good respiratory function, and promotes early recovery. [Copyright &y& Elsevier]

Vietnamese people use mugwort (Artemisia vulgaris L.) to treat arthritis and gout. Our previous research shows that mugwort contains flavonoids, and its extract possesses antibacterial and anti-inflammatory activities. However, no publications have been on the xanthine oxidase inhibitory activity of mugwort and acute anti-inflammatory activity in vivo. The study aimed to verify the antioxidant, xanthine oxidase inhibitory, and anti-inflammatory capabilities of mugwort extract in vitro and in vivo , isolate phyto-compounds from potential bioactive fractions, and then evaluate their potential in inhibiting xanthine oxidase. According to established methods, the extract and the active flavonoids were obtained using different chromatographic techniques. DPPH, ABTS, reducing power, and H 2 O 2 elimination were used to evaluate antioxidant activity. The model of LPS-induced RAW264.7 cells was used to measure the inhibition of NO production. The carrageenan-induced paw oedema model was used to assess acute inflammation in mice. In vitro, xanthine oxidase inhibition assay was applied to investigate the effects of extract/compounds on uric acid production. Chemical structures were identified by spectral analysis. The assessment of the acute inflammatory model in mice revealed that both the 96% ethanol and the 50% ethanol extracts significantly decreased oedema in the mice's feet following carrageenan-induced inflammation. 96% ethanol extract exhibited a better reduction in oedema at the low dose. The analysis revealed that the ethyl acetate fraction had the highest levels of total polyphenols and flavonoids. Additionally, this fraction demonstrated significant antioxidant activity in various assays, such as DPPH, ABTS, reducing power, and H 2 O 2 removal. Furthermore, it displayed the most potent inhibition of xanthine oxidase, an anti-inflammatory activity. Five phytochemicals were isolated and determined from the active fraction such as luteolin (1), rutin (2), apigenin (3), myricetin (4), and quercetin (5). Except for rutin, the other compounds demonstrated the ability to inhibit effective xanthine oxidase compared to standard (allopurinol). Moreover, quercetin (5) inhibited NO production (IC 50 21.87 μM). The results indicate that extracts from A. vulgaris effectively suppressed the activity of xanthine oxidase and exhibited antioxidant and anti-inflammatory properties, potentially leading to a reduction in the production of uric acid in the body and eliminating ROS. The study identified mugwort extract and bioactive compounds derived from Artemisia vulgaris , specifically luteolin, apigenin, and quercetin, as promising xanthine oxidase inhibitors. These findings suggest that further development of these compounds is warranted. At the same time, the above results also strengthen the use of mugwort to treat gout disease in Vietnam. [Display omitted] • Ethanol 96% and 50% of mugwort extract indicate antioxidant, anti inflammatory, xanthine oxidase inhibition activities. • Ethanol 96% extract demonstrated an enhanced anti-inflammatory effect at low doses compared to ethanol 50% extract in vivo. • Ethyl acetate fraction contain highest amount of total polyphenol and flavonoid content. • Ethyl acetat fraction inhibit of xanthine oxidase, antioxidant and suppress NO production. • Five flavonoids isolated from ethyl acetat fraction can inhibit xanthine oxidase. [ABSTRACT FROM AUTHOR]

This paper considers the performance of a full-duplex (FD) vehicle-to-vehicle (V2V) relay system where the relay uses amplify-and-forward (AF) protocol and harvests the energy from the radio frequency (RF) signals transmitted by source. Unlike previous reports, we investigate the case that both relay and destination are moving vehicles. Therefore, the channel between source and relay is Rayleigh fading while the channel between relay and destination is cascade (double) Raleigh fading. In addition, both fixed and variable gains are used at the FD relay. Based on mathematical analysis, we successfully derive the exact closed-form expressions of the outage probability (OP) and symbol error probability (SEP) to evaluate the system performance. Monte-Carlo simulations are exploited to demonstrate the correctness of all derived mathematical expressions. Numerical results clearly indicate that the OP and SEP performance of the considered energy harvesting (EH)-FD-V2V relay system with variable gain is much better than that with fixed gain. Moreover, the OP and SEP performance are strongly impacted by residual self-interference (RSI) due to the incomplete noise cancellation during the FD transmission. Besides the RSI, the OP and SEP performance is greatly reduced because of the cascade Rayleigh fading. We also observe that there is an optimal EH time duration to minimize the OP and SEP and this optimal value is different for fixed and variable gains. Therefore, from the transmission power of source and the type of gains used at FD relay, we can choose a suitable time EH time duration to get the best system performance. [ABSTRACT FROM AUTHOR]

Abstract Transition-metal dichalcogenide monolayers recently have attracted much attention motivated by their exotic physical properties. In this paper, we theoretically investigate the optical absorption in the monolayer MoS 2 which is subjected to a uniform static magnetic field and an electromagnetic wave. The magneto-optical absorption power (MOAP) is calculated using the projection operator technique in the linear response scheme, taking account of the electron–optical phonon interaction at high temperature. Both phonon emission and phonon absorption processes are included. The cyclotron–phonon resonance (CPR) is observed in the photon energy dependence of the MOAP. Numerical analyses show that the photon energy satisfying CPR condition depends linearly on the strength of magnetic field, which is similar to that in conventional low-dimensional semiconductors but different from that in graphene. The increase of the full width at half maximum (FWHM) of CPR peaks with increasing magnetic field shows a similar behaviour to that in graphene. In addition, FWHM increases slightly with temperature, which is different from that in graphene where the FWHM is temperature independent. Our investigation provides basic information about the magneto-optical properties of the monolayer MoS 2 that are useful for further experiments and applications. Highlights • The cyclotron-phonon resonance is observed in the absorption power. • The CPR peaks exhibit a blue-shift as the magnetic field increases. • The FWHM is proportional to the magnetic field. • The FWHM increases slightly with increasing temperature. [ABSTRACT FROM AUTHOR]

Antibiotic-resistant bacteria have become a serious problem worldwide, caused in part by the excessive use and discharge of antibiotics into the environment. Ampicillin (ABPC) is a widely used antibiotic. However, this chemical rapidly decomposes in water containing divalent cations like Ca 2+ and Mg 2+ , thus, detection of ABPC in environmental water is difficult. This study was carried out to evaluate the presence of 2-hydroxy-3-phenylpyrazine (HPP), one of the degradation products of ABPC and β-lactam antibiotics with an ABPC substructure, in environmental water. An analytical method for HPP monitoring in environmental water was developed using liquid chromatography/tandem mass spectrometry. The analyte was extracted from water samples and enriched using a solid-phase extraction cartridge. The quantification limit was 1 ng L −1 . The HPP recovery rates from spiked water samples of 25 and 125 ng L −1 were 84.1 and 86.1%, respectively. The method was then used to determine HPP residue levels in 98 environmental water samples from rivers, household ponds, and aquacultural ponds in Vietnam. HPP residues were detected in 60 samples. The HPP detection rates in rivers and household ponds were 42 and 79%, respectively. HPP was not detected in aquacultural ponds. HPP residue concentrations in the samples ranged from 1.3 to 413.3 ng L −1 . The residue levels in rivers flowing through city centres were higher than levels in other sampling locations. The findings of this study suggest that HPP is a promising marker for assessing the discharge of ABPC and β-lactam antibiotics with an ABPC substructure into the environment around sampling sites. [ABSTRACT FROM AUTHOR]

• An NMR instrumentation is developed to measure 3D velocity fields in microdevices. • MRI measurements in an arrow-type micromixer are compared to CFD simulations. • Small manufacturing defects strongly affect the flow and the mixing performance. • Good agreement is obtained between numerical data and experimental measurements. 3D velocity field measurements in an arrow-type micromixer are performed using nuclear magnetic resonance (NMR) imaging methods. A specific device has been set up including a home-made radiofrequency milli-coil matching the geometry of the manufactured micromixer, allowing an improvement of the signal-to-noise ratio by a factor 7 comparing to a standard commercial hardware. The NMR images obtained are compared to computational fluid dynamics (CFD) simulations. The very good agreement obtained between numerical data and experimental measurements revealed, on the one hand, the capacity of the developed method to perform a detailed and accurate study of phenomena occurring in a microstructured system and on the other hand, the great impact of small manufacturing defects on the hydrodynamics in a micromixer and thus on the mixing performances. [ABSTRACT FROM AUTHOR]

In our previous research on Vietnamese medicinal plants, we found that the ethanolic extract of the aerial parts of Paris polyphylla var. chinensis exhibited cytotoxic effects in vitro in the MCF-7 human cancer cell line. Here, we used combined chromatographic separations to isolate six compounds including a new steroid glycoside, paripoloside A (3), and five known compounds, from the butanol extract of the aerial parts of P. polyphylla. We unambiguously elucidated their structures based on spectroscopic data (proton and carbon-13 nuclear magnetic resonance, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, correlation spectroscopy, and high-resolution electrospray ionization mass spectroscopy data), and chemical reactions. Among the isolated compounds, paris saponin II (PSII) had the strongest cytotoxic effects against MCF-7 breast cancer cells. Interestingly, PSII significantly increased the expression of p53, p21, p27, and Bax protein levels and significantly suppressed the expression of cyclin D1 and retinoblastoma protein. These data suggest that PSII may induce G1/S phase cell cycle arrest and apoptosis pathway development in MCF-7 cells. Furthermore, the MCF-7 breast cancer cells mechanism of PSII was also investigated using molecular docking. Together, our results demonstrate that isolated compounds from P. polyphylla are promising candidates as breast cancer inhibitors. [Display omitted] • Phytochemical investigation of Paris polyphylla var. chinensis was performed. • Their structures were determined by means of the spectroscopic methods, and chemical reactions. • The cytotoxicity mechanism of compound 5 was explored using molecular docking, and Western blotting experiments. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Ganoderma lucidum (Fr.) Karst. (Ganodermataceae) is a mushroom which is used as a traditional remedy in the treatment of human diseases such as hepatitis, liver disorders, hypercholesterolemia, arthritis, bronchitis and tumorigenic diseases. This study targets the evaluation of hepatoprotective activity of ganodermanontriol, a sterol isolated from Ganoderma lucidum, and the investigation of its mechanism of action in Hepa1c1c7 and murine liver cells upon tert-butyl hydroperoxide (t-BHP)-induced inflammation. t-BHP was utilized to stimulate an anti-inflammatory reaction in the hepatic cell lines and murine hepatic tissue examined. Western blot and reverse transcription-quantitative polymerase chain reaction (RT-PCR) were used to estimate the expression of ganodermanontriol (GDT)-induced proteins, including heme oxidase-1 (HO-1) and mitogen-activated protein kinases (MAPKs) as well as the corresponding mRNA. Luciferase assays were conducted to evaluate the interaction between NF-E2-related factor-2 (Nrf-2), the antioxidant response element (ARE), and the promoter region of the HO-1 gene and subsequent gene expression. Biochemical markers for hepatotoxicity were monitored to assess whether GDT protected the cells from the t-BHP-mediated oxidative stimuli. Results: GDT induced HO-1 expression via the activation of Nrf-2 nuclear translocation and the subsequent transcription of the HO-1 gene in vitro and in vivo, which seemed to be regulated by phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) and p38 signaling pathways. GDT exhibited in vitro and in vivo hepatoprotective activity as determined by the lowered levels of hepatic enzymes and malondialdehydes and the elevated glutathione levels. Conclusions: This study validates the ethnopharmacological application of Ganoderma lucidum as a treatment for hepatic disorders. GDT induced in vitro and in vivo anti-inflammatory activity in t-BHP-damaged hepatic cells through the expression of HO-1, and in which PI3K/Akt and p38 kinases are involved. Our study motivates further research in the exploration of potent hepatoprotective agents from Ganoderma lucidum. [Copyright &y& Elsevier]

In practice, traditional wireless communication systems are often affected by various negative factors such as channel estimation errors (CEE) and transceiver hardware impairments (THI). For in-band full-duplex (FD) communication systems, besides CEE and THI impacts, imperfect self-interference cancellation will significantly degrade the system performance because of residual self-interference (RSI). This paper aims to investigate the performance of a multiple-input multiple-output (MIMO) FD relay (FDR) system in realistic scenarios where the impacts of CEE, THI, and RSI are taken into account. We mathematically derive the exact closed-form expression of symbol error rate (SER) of the considered MIMO-FDR system and validate the derived expression by Monte-Carlo simulations. Numerical results indicate that the impacts of three imperfect factors (CEE, THI, and RSI) are remarkable. Specifically, with the considered values of CEE, THI, and RSI, the impact of CEE on the SER is most substantial. Additionally, compared with the ideal system (perfect channel estimations, transceiver hardware, and self-interference cancellation), the SER of the considered system is significantly higher and goes to the error floor fast. Therefore, it is crucial to apply all solutions for reducing the CEE, THI, and RSI in the considered MIMO-FDR system. [ABSTRACT FROM AUTHOR]

In this paper, we propose and analyze a multi-user non-orthogonal multiple access (NOMA) relaying system under the effect of Nakagami- m fading. In this system, both source and the relay harvest the energy from a multiple-antenna power beacon (PB) in the first time duration by using the time switching protocol and then use the harvested energy to transmit and receive the signals in the remaining time duration. We derive the exact closed-form expressions of the outage probability in two cases of successive interference cancellation (SIC), i.e., perfect SIC and imperfect SIC. Moreover, we determine the optimal time switching ratio that maximizes the system throughput. We also compare the achievable sum rate of the proposed NOMA relaying system with that of the orthogonal multiple access (OMA) relaying system. The correctness of all derived mathematical expressions results in this paper is verified by Monte-Carlo simulations. Numerical results show that: (1) the fading severity of wireless channels has a significant impact on the outage probability and the diversity; (2) increasing the number of antennas of PB helps to lower the outage probability, decrease the energy harvesting time, and increase the throughput; (3) the sum rate of the proposed NOMA relaying system is proportional to the SIC quality and is higher than that of the OMA relaying system in the low and moderate signal-to-noise ratio (SNR) regimes. [ABSTRACT FROM AUTHOR]