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Plant pathogenic fungi and bacteria cause large losses in the yield and quality of important crops. During the screening of bioactive plants against plant pathogens, we found that methanol extract of the aerial part of Rumex chinensis exhibited potent efficacy against various plant diseases. The methanol extract was effectively active against phytopathogenic fungi Blumeria graminis f. sp. hordei and Colletotrichum coccodes that cause plant diseases in vivo. n-Hexane and ethyl acetate layers obtained by liquid-liquid partitioning of the methanol extract strongly suppressed these fungal diseases with control values from 83 to 100% at 3000 µg/mL. These layers also inhibited the bacterial growth of Acidovorax avenae subsp. cattleyae and Ralstonia solanacearum. Notably, the n-hexane layer was found to reduce the development of tomato bacterial wilt in vivo. Six anthraquinones and two sterols were isolated from the aerial part of R. chinensis. Besides, the high-performance liquid chromatography (HPLC) was used for the quantitative analysis of anthraquinone contents in the active layers. The aerial part of R. chinensis was proved to be rich in active substances physcion, chrysophanol and emodin and their glycoside derivatives. Our findings suggested that the extracts and metabolites from the aerial part of R. chinensis could be used as potent active ingredients for developing botanical fungicide and bactericide to control plant diseases.

One of the main factors in the capacity of passive autocatalytic recombiners (PARs) is its productivity or the hydrogen removal rate. In this work it was demonstrated that regardless of the type of a recombiner, the hydrogen removal rate is mostly determined by the catalytic surface area and the molar density of hydrogen at the inlet. It means that the performance of a recombiner should obey geometric and physical scalability. Geometric scalability is characterized by the retention of the specific (per unit area of the catalytic surface) hydrogen removal rate with increasing the size of the recombiner by increasing the inlet section while maintaining the height and design of the catalytic unit. Physical scalability is characterized by maintaining the hydrogen removal rate of the recombiner at a constant input molar density of hydrogen in an air-hydrogen environment while simultaneously changing the input temperature and pressure. For a numerical demonstration of scalability, several calculations were performed with different initial hydrogen concentrations, external conditions and amounts of catalytic elements. It was shown that, regardless of the number of catalytic plates in the recombiner, the specific removal rate of hydrogen will remain unchanged and that under different external conditions (temperature, pressure), in case they correspond to the same inlet hydrogen density, the hydrogen removal rate does not change.

Fineroots (≤ 2 mm diameter) are dynamic components of the forest ecosystems and play important role in water and nutrient acquisition in forests. These roots are sensitive to forest fertilization and therefore, the response of fineroots to nutrient application would provide better understanding of the forest carbon and nutrient dynamics that will be helpful in sustainable forest management plans. Two fertilization treatments, including (1) F400: 400 g P2O5 (16.5%)/tree and (2) F600: 600 g P2O5 /tree, and F0: control (without fertilization), were applied in an Acacia mangium plantation with a planting density of 1100 trees/ha (3 m × 3 m). The evaluation of fineroot growth across seasons showed that fertilization significantly increased production and subsequent mortality and decomposition. The total decomposition associated with F600 application was 7.95 tons ha−1 year−1, equaling 121% of F400 and 160% of the control. Mortality in F600 was 8.75 tons ha−1 year−1, equaling 111% of F400 and 198% of F0, while production in F600 was 10.40 tons ha−1 year−1, equaling 127% of F400 and 143% of F0. Fineroot production, mortality, and decomposition are seasonally dependent, with higher values measured in the rainy season than in the dry season. Stand basal area increment was significantly correlated with fineroot production (R2 = 0.75), mortality (R2 = 0.44), and decomposition (R2 = 0.48). This study showed that fertilization could facilitate fineroot production, which can then lead to a higher turnover of carbon and nutrients through the decomposition of the greater mass of the fineroots.

Mục tiêu: Nhận xét hiệu quả, dung nạp và tuân thủ phác đồ lactulose trong làm sạch đại tràng trước nội soi không can thiệp đốt điện ở trẻ em tại Bệnh viện Nhi Trung ương.Đối tượng và phương pháp nghiên cứu: Nghiên cứu can thiệp không đối chứng. Thông tin nghiên cứu được thu thập từ tất cả các trẻ từ 0-18 tuổi được chỉ định nội soi đại tràng không can thiệp đốt điện để làm sạch đại tràng bằng lactulose kết hợp với thuốc thụt glycerol và phosphate được nội soi đại tràng tại khoa Nội soi, Trung tâm Tiêu hóa-Gan mật-Dinh dưỡng, Bệnh viện Nhi Trung ương trong tháng 11 năm 2020. Sử dụng phiếu khảo sát được thiết kế để thu thập thông tin qua phỏng vấn phụ huynh/người giám hộ trẻ.Kết quả: Điểm Boston toàn bộ đại tràng 8,1±1,2 điểm, 72,5% trẻ có điểm đại tràng sạch xuất sắc, 22,5% trẻ có đại tràng sạch, chỉ 5,0% trẻ có điểm làm sạch đại tràng kém, 03 trẻ chỉ sử dụng lactulose mà không cần thuốc thụt. Tỷ lệ trẻ gặp các tác dụng không mong muốn thoáng qua khi sử dụng phác đồ làm sạch đại tràng bằng lactulose bao gồm buồn nôn/nôn (25%), đau bụng (17,5%). Trung bình lượng lactulose trẻ đã uống 101,9±36,3 ml khôngít hơn nhiều so với lượng lactulose trẻ cần uống theo phác đồ làm sạch. Tỷ lệ trẻ uống dung dịch lactulose một cách dễ dàng (85%) cao hơn nhiều so với trẻ thể hiện sự khó chịu do dung dịch quá ngọt (25%).Kết luận: Phác đồ chuẩn bị đại tràng dành cho nội soi không can thiệp đốt điện, sử dụng dung dịch lactulose đạt hiệu quả LSĐT cao với khả năng dung nạp và tuân thủ tốt ở trẻ em.

Recently, indium tin oxide has been very attractive for thermo-optic (TO)-controlled silicon photonic devices, due to its high transparency, strong TO phase dependency, high conductivity, and CMOS compatibility. These properties enable the reduction of the gap between the silicon core and the heater, leading to a considerably low electric power consumption and high switching speed. We present an investigation of a numerical simulation to design and optimize a compact ITO microheater for tuning the TO phase shift in a proof-of-concept of a three-mode converter (TMC) with broadband and ultralow loss properties. We show that the TMC can operate the 3-dB bandwidth up to 100 nm. In addition, the designed device can attain relatively large fabrication tolerances for width and height of ±50 and ±5 nm, respectively. In addition, the proposed mode converter consumes a total power of less than 90 mW and obtains a fast switching time of less than 8 μs. Moreover, the device can be integrated into an estimated compact footprint of 8 μm × 2160 μm. Such excellent performances make ITO a strong candidate for low-loss TO phase shifters and open up an alternative method for realizing ultrafast and high-speed mode division multiplexing systems and large-scale applications.

Multi-axial mechanical systems commonly encounter the problem of vibration while attempting to drive machining systems at high speed. Many effective methods based on feed-forward and feedback control have been proposed and applied for vibration reduction. In order to design controllers all methods require the exact knowledge of system parameters: vibration frequency and damping ratio. In recent years, low-cost Micro Electro Mechanical Systems (MEMS) accelerometers have been used for many applications in industry. This paper presents the advantage of low cost MEMS accelerometer to identify vibration parameters of mechanical systems in comparison to conventional expensive devices.

Net primary production (NPP) is an important index for understanding carbon cycling in forest ecosystems. In this study, aboveground NPP at Acacia mangium plantation was estimated basing on allometry for aboveground biomass increment (ΔM) and litter trap technique for litterfall (Lf). The experiment was conducted in two plots of 300 m2 each (15 × 20 m), established at a 21-month old plantation. Data were collected five times of 3-month intervals in a total duration of 357 days. The results indicated that Lf and ΔM were seasonal-dependent. Litterfall was highest (4.06 g m-1 day-1) during Sep-Jan (late rainy season, early winter) and lowest (1.10 g m-1 day-1) during Mar-Jun (early rainy season, early summer). While, ΔM was highest (13.51 g m-1 day-1) during Jun-Sep (rainy season, summer) and lowest (3.10 g m-1 day-1) during Jan-Mar (dry season, winter). Total Lf in a duration of 357 days was 9.69 tons ha-1 and ΔM was 27.71 tons ha-1, leading to total aboveground NPP of the present study plantation of 37.40 tons ha-1. It is concluded that aboveground NPP of acacia plantation was much higher than other forests of different types and ages around the world. Such difference indicates the importance of acacia plantation in soil nutrient cycling through litterfall decomposition and carbon sequestration through aboveground biomass increment.

Biotic and abiotic factors control aboveground biomass (AGB) and the structure of forest ecosystems. This study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam. A data set of 173 1-ha plots from 52 locations in undisturbed old-growth forests was developed. The results indicate that basal area and AGB are closely correlated with annual precipitation, but not with annual temperature, evaporation or hours of sunshine. Basal area and AGB are positively correlated with trees > 30 cm DBH. Most areas surveyed (52.6%) in these old-growth forests had AGB of 100–200 Mg ha−1; 5.2% had AGB of 400–500 Mg ha−1, and 0.6% had AGB of > 800 Mg ha−1. Seventy percent of the areas surveyed had stand densities of 300–600 ind. ha−1, and 64% had basal areas of 20–40 m2 ha−1. Precipitation is an important factor influencing the AGB of old-growth, evergreen broadleaved forests in Vietnam. Disturbances causing the loss of large-diameter trees (e.g., > 100 cm DBH) affects AGB but may not seriously affect stand density.

The rotifer fauna in three hydroelectric reservoirs of western highlands, central Vietnam were studied. Among a total of 63 identified species and subspecies, beloging to 23 genera in 15 families, Brachionidae was the most diverse family with 15 taxa recorded (23.81%) followed by Lecanidae (14 taxa, 22.22%), and Synchaetidae (8 taxa, 12.7%). Species accumulation curve and species richness estimators suggested a relatively high level of biodiversity of rotifera assemblages in the studied area. Besides, results on species composition of rotifera community in this study were compared to those of other freshwater bodies in Vietnam using Jaccard similarity index. In particular, the highest similarity was found between reservoirs in western highlands and Phu Ninh lake, Quang Nam Province while the largest difference in species composition was observed between western highlands and Bau Thiem lake, Thua Thien Hue Province.

The Basel agreements and the associated European directives have made banking prudential capital contingent on their risk profile rather than on their size or turnover. The Solvency 2 Directive (hereinafter the "Directive") repeats this process for European insurers and reinsurers. It constitutes a total paradigm shift for the majority of European insurers. It defines the main regulatory principles aimed at regulating their activity and in particular determining the amount of prudential capital associated with the risks inherent to their activity.In accordance with the directive, the prudential capital corresponds in principle to an insurer with a 99.5% percentile of the change in its basic own funds over the coming year. Such a prospective risk measure requires for an insurer the ability to address two problems: a valuation problem and a simulation problem. In practice, the 99.5% percentile of the change in basic own funds is estimated using the MonteCarlo method. It is particularly sensitive to the one-year law retained for the risk factors vector. Its Monte Carlo valuation would ideally require the simulation of one year risk factor vector x and the valuation of the associated equity values. Given the significant calculation time required for numerical evaluation, this approach is in practice unsuitable. In order to circumvent this problem, the insurers have developed many approximate methods or "proxies" which make it possible to approximate the basic own funds value instantaneously. Today, these methods are rarely accompanied by error controls that would measure the simulation quality. More precisely, the methods currently used by the insurers do not make it possible to control naturally the approximation error generated by the use of the proxy model instead. The proposed error checks are therefore always empirical and too approximate.In order to solve this problematic, we propose, in a first part of this thesis, a new method of constructing the proxy that is both resource-efficient and offers rigorous error control. The second part of this thesis aims at applying the extreme value theory to the prudential capital estimate when information on the covariate is available. In particular, when the covariate is high dimensional, we are confronted with the problem of the curse of dimensionality, which translates into a decrease in the fastest possible convergence rates of estimators of the regression function to their target curve. This problem refers to the phenomenon where the volume of the covariate increases so rapidly that available data become sparse. To obtain a statistically reliable result, the amount of data needed to support the result often increases exponentially with dimensionality, which is generally problematic in many practical applications. To overcome this estimation problem, we propose a new efficient evaluation methodology by combining the generalized additive model and the sparse group lasso method.; Les accords de Bale et les directives européennes associées ont conduit à conditionner les capitaux prudentiels des banques à leur profil de risqué plutôt qu’à leur taille ou chiffre d’affaire. La directive Solvabilité 2 (ci-après la "directive") répète ce processus pour les assureurs et réassureurs européens. Elle constitue un changement total de paradigme pour la majorité des assureurs européens. Elle définit les grands principes réglementaires visant à encadrer leur activité et en particulier à déterminer le montant des capitaux prudentiels associés aux risques inhérents à leur activité.Conformément à la directive, le capital prudentiel correspond en principe pour un assureur au quantile à 99.5% de la variation de ses fonds propres sur l’année à venir. Une telle mesure de risque prospective requiert pour un assureur la capacité d’adresser deux problèmes : un problème de valorisation et un problème de simulation. En pratique, le quantile à 99.5% de la variation de ses fonds propres est estimépar la méthode de Monte-Carlo. Il est particulièrement sensible à la loi jointe à un an retenue pour le vecteur de facteurs de risque x. Son évaluation par méthode de Monte-Carlo nécessiterait idéalement de simuler m réalisations du facteur de risque x à un an et d’évaluer les valeurs des fonds propres associées. Compte tenu du temps de calcul important nécessaire à l’évaluation numérique, cette approche s’avère en pratique inadaptée. De manière à contourner ce problème, les opérationnels ont mis au point de nombreuses méthodes d’approximation ou « proxys » qui permettent d’en approximer la valeur de manière instantanée. Aujourd’hui, ces méthodes sont rarement accompagnées de contrôles d’erreur qui permettraient d’en mesurer la qualité. Plus précisément, les méthodes actuellement utilisées par les opérationnels ne permettent pas de contrôler naturellement l’erreur d’approximation engendrée par l’utilisation du modèle proxy en lieu. Les contrôles d’erreur proposés sont donc toujours empiriques et trop approximatifs.Afin de résoudre cette problématique, nous proposons, dans une première partie de cette thèse, une nouvelle méthode de construction du proxy à la fois économe en ressources informatiques et offrant un contrôle d’erreur rigoureux. La deuxième partie de cette thèse a pour l’objectif d’appliquer la théorie de la valeur extrême à l’estimation du capital prudentiel lorsque l’information sur la covariable est disponible. En particulier, lorsque la covariable est de grande dimension, nous sommes confrontés au problème de la "curse of dimensionality", qui se traduit par une diminution des taux de convergence les plus rapides possibles des estimateurs de la fonction de régression vers leur courbe cible. Ce problème fait référence au phénomène où le volume de la covariable augmente si rapidement que les données disponibles deviennent rares. Pour obtenir un résultat statistiquement fiable, la quantité de données nécessaire à l’appui du résultat augmente souvent de manière exponentielle avec la dimensionnalité, ce qui est généralement problématique dans de nombreuses applications pratiques. Pour surmonter ce problème d’estimation, nous proposons une nouvelle méthodologie d’évaluation efficace en combinant le modèle additif généralisé et la méthode de sparse group lasso.

In this paper, the synthesis of nickel ferrite and its use for voltammetric determination of uric acid (UA) are presented. Nickel ferrite was synthesized via a hydrothermal process using spherical carbons as hard template followed by calcination at 500 °C. It was found that iron and nickel compositions in nickel ferrite can be controlled by the initial Fe/Ni molar ratio. The stoichiometric nickel ferrite (NiFe2O4) with hollow spherical morphology was obtained from a reaction mixture with Fe/Ni molar ratio of around 1.2–1.5. Glassy carbon electrode modified with nickel ferrite was employed to quantitatively determine UA by different pulse voltammetric method. Under the optimum conditions, the anodic peak current was linearly proportional to UA concentration in the range of 0.398 to 6.761 μM. The detection limit (3σ) was found to be 0.15 μM. The proposed method has been employed to determine UA in human urine samples with acceptable recoveries of 95.15–104.8%. On the other hand, the results obtained from this method were also compared with that from standard HPLC method, showing no statistical difference.

Objective. To characterize the types of cognitive and metacognitive processes demonstrated by third-year pharmacy students during a therapeutic reasoning activity. Methods. A qualitative, descriptive study following a think-aloud protocol was used to analyze the cognitive (analytical) and metacognitive processes observed by third-year pharmacy students as they completed a 25-minute therapeutic reasoning activity. Using a deductive codebook developed from literature about reasoning, two independent coders characterized processes from students’ audio-recorded, transcribed think-aloud episodes while making therapeutic decisions about simulated clinical cases. Results. A total of 40 think-aloud episodes were transcribed among the cohort. Categorization of the think-aloud transcriptions revealed a series of cognitive analytical and metacognitive processes demonstrated by students during the therapeutic decision-making activity. A total of 1792 codes were categorized as analytical processes, falling into six major themes: 69% gathering information (1232/1792), 13% processing information (227/1792), 7% making assessments (133/1792), 1% synthesizing information (19/1792), 7% articulating evidence (117/1792), and 4% making a recommendation (64/1792). In comparison to gathering information, a much lower frequency of processing and assessment was observed for students, particularly for those that were unable to resolve the case. Students’ movement between major analytical processes co-occurred commonly with metacognitive processes. Of the 918 codes categorized as metacognitive processes, two major themes arose: 28% monitoring for knowledge or emotions (257/918) and 72% controlling the planning of next steps or verification of correct information (661/918). Sequencing the codes and co-occurrences of processes allowed us to propose an integrated cognitive/metacognitive model of therapeutic reasoning for students. Conclusion. This study categorizes the cognitive (analytical) and metacognitive processes engaged during pharmacy students’ therapeutic reasoning process. The findings can inform current instructional practices and further research into educational activities that can strengthen pharmacy students’ therapeutic reasoning skills.

Multi-Frequency Network (MFN) in Digital Terres-trial Television Broadcasting (DTTB) is mainly suitable for the countries that wish to implement a high capacity broadcasting network for rooftop reception. Whereas, Single Frequency Network (SFN) in DTTB has many advantages over MFN particularly in spectrum efficiency, quality of coverage, and flexibility in network implementation. This study mainly focuses on the comparison of the quality of radio coverage due to MFN-based and SFN-based DTTB systems. The Digital Video Broadcasting-Second Generation Terrestrial (DVB-T2) implemented in Kath-mandu, Nepal is taken as a reference network for simulation purposes. An MFN is contrasted with three types of SFNs in terms of area of radio coverage, population coverage, received signal strength, and the data rates so that the results can assist in the smooth deployment of a DTTB system.

Various Elaeocarpus species including Elaeocarpus tonkinensis have been important medicinal plants that used in traditional medication system and mainly used to cure nervous system-related disorders. However, their antiviral potential has not been reported yet. During the screening of medicinal plant extracts with the antiviral activity against influenza viruses, we found that E. tonkinensis extract has strong antiviral activity. Through organic solvent partition and repeated column chromatography using SiO 2, C-18 and Sephadex LH-20, a total of nine compounds were purified from the methanol extract of E. tonkinensis. Their chemical structures were determined by NMR and MS spectral data to be trolliamide (1), gallic acid (2), urolithin M-5 (3), hydroquinone (4), 2,4-dihydroxybenzoic acid (5), 3,5-dihydroxy-4-methoxybenzoic acid (6), corilagin (7), chebulagic acid (8), and shikimic acid (9). Their antiviral activity against influenza virus strains A/Puerto Rico/8/34 (H1N1; PR8), A/Hong Kong/8/68 (H3N2; HK) and B/Lee/40 (Lee) was examined on the basis of cytopathic effect (CPE) assay. Among them, compounds 2, 3, 4, 7, and 8 significantly inhibited viral replication in a dose-dependent manner with EC 50 values ranging from 7.8 to 59.6 μg/mL against influenza A and/or B viruses with selectivity indices above 5.0. This study suggests that the botanical materials of E. tonkinensis could be promising inhibitors of influenza A andB viruses and applied to the development of a novel herbal medicine.

We design a 4×4 single-mode optical switch which is capable of switching four fundamental modes from four input ports to any of the four output ports. The proposed device consists of two 4×4 multimode interference couplers on an SOI platform with 220 nm thick Si layer. Mode signals selected at the desired output were determined by four phase shifters placed between two MMIs. Through numerical simulation method BPM combined with EIM method, we evaluate optical conversion efficiency when transmitting optical mode signals at any input and measuring optical power at outputs. At 1550 nm central wavelength, insertion loss is always less than 0.1 dB and below 1.6 dB in the entire C band. Furthermore, the crosstalk is always from -110 dB to -50 dB in a range of band of 35 nm.

In this paper, we introduce a structure can generate simultaneously three lowest optical modes TE 0 , TE 1 and TE 2 based on SOI platform. This device is built on two tridents and one Multimode interference (MMI) couplers. It is designed using 3D beam propagation method (3D-BPM) combined with effective index method (EIM). The simulation results show that the proposed device can operate in a wide wavelength range up to 140nm covering whole C and almost of L and S bands with low insertion loss, about -0.23 dB at the central wavelength of 1550 nm. Manufacturing tolerances of the device is rather large. In addition, the small footprint (5 µm×506 µm) makes the device not only compatible with the current CMOS manufacturing technology but also suitable with high bitrate applications of photonic integrated circuits inside MDM-WDM systems.

In order to realize next generation digital terrestrial television broadcasting (DTTB) systems, the currently deployed Integrated Services Digital Broadcasting Terrestrial (ISDB-T) is still essential due to the spectrum-scarcity. This paper proposes a layered division multiplexing (LDM) scheme to simultaneously transmit ISDB-T stream and a secondary data stream over a common frequency band. The next generation DTTB system can be obtained by combining the ISDB-T and the secondary data streams. In the proposed scheme, we deploy the primary layer for transmission of ISDB-T signal and the secondary layer for transmission of secondary data stream both employed space time block coding. In addition, we only adopt partial LDM to reduce the interference between two systems, since the transmission capacity of the secondary layer exceeded the minimum requirement due to reuse of primary layer.

The antimicrobial efficacies of extracts and constituents fractionated from Rheum tanguticum rhizomes were evaluated by using in vitro and in vivo bioassay against seven phytopathogenic fungi and ten pathogenic bacteria, respectively. Dichloromethane and ethyl acetate soluble extracts derived from R. tanguticum rhizomes effectively controlled plant diseases caused by five fungi Magnaporthe oryzae, Blumeria graminis f. sp. hordei, Colletotrichum coccodes, Phytophthora infestans, and Puccinia recondita in in vivo whole plant bioassay. In addition, these extracts showed strong inhibitory activity against the bacterial growth of Acidovorax avenae subsp. cattlyae (Aac), Clavibacter michiganensis subsp. michiganensis, Xanthomonas arboricola pv. pruni (Xap), and Pseudomonas syringae pv. actinidiae (Psa), with MIC values ranging from 125 to 250 μg/mL. The active extracts of R. tanguticum rhizomes were fractionated by using various and repeated chromatographic techniques to yield seven constituents that included three anthraquinones and four stilbenes. Notably, at concentrations ranging from 75 to 300 μg/mL, physcion (DH03) and chrysophanol (DH04) were significantly effective in suppressing the development of barley powdery mildew (BPM) caused by B. graminis f. sp. hordei, with control values from 80 to 96.7%. Moreover, stilbenes rhapontigenin (DH02) and desoxyrhapontigenin (DH05) had a broad spectrum and potent activity against phytopathogenic bacteria; DH05 effectively inhibited the bacterial growth of Aac, Burkholderia glumae and Psa at MICs ranging from 38 to 150 μg/mL. In this paper, we report their antibacterial activity for the first time. The botanical materials containing anthraquinones and stilbenes were active against both phytopathogenic fungi and bacteria. These results suggested that R. tanguticum rhizomes could be used as a new source of antimicrobial substances for developing a botanical fungicide and bactericide to control plant diseases.