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Anomaly detection is essential to guarantee the correctness of sensory data collected from Internet of Things. The latest detection approaches only operate under one of the two general forms of short-term or long-term anomaly. In this article, we propose monotone split and conquer (MSC) scheme to tackle both anomaly forms. The proposed scheme exploits the spatial–temporal correlation between neighboring sensors to detect abnormal sensory data. MSC splits the collected data into monotonic subtrends in the training phase to establish the trend-based normal profiles for the online detection phase. To eradicate the overfitting phenomenon, we further develop a general formulation to estimate the square prediction error (SPE) control limit. Both monotone split and general formulation contribute to the advancement of MSC in terms of accuracy (ACC) and false positive rate (FPR) in the online detection phase. To evaluate the performance of MSC, we design a general anomaly model to generate artificial short-term and long-term anomalies. Numerical experiments with the Intel Berkeley Research Lab (IBRL) data set demonstrate that MSC obtains about 8% higher ACC and 5% lower FPR on average when compared to existing schemes. Remarkably, MSC requires only a few observations for anomaly detection as it is applicable to real-time systems.

Charybdis feriata (Linnaeus, 1758) is wide distribution and high economic value species in many countries around the world. In Vietnam, Charybdis feriata is on the list of endangered species that need to be conserved. Parasites cause many effects on the growth and development of crabs, which may be one of the causes leading to the decline of host populations. This paper presents the species composition, parasitic sites and infection status of parasitic crustaceans on C. feriata in Nha Trang Bay. From 113 individuals of Charybdis feriata collected in June and July 2022, we have identified 6 species of parasitic crustaceans, of which 2 species have been recorded for the first time on this crab, including: Octolasmis neptuni, Semibalanus sp.. Each infested crab is infected with up to 5 species of parasites. Octolasmis angulata was the dominant species with the highest prevalence and median intensity of infection at 44.4% and 6.5 individuals/infected crabs, respectively. Comparison of infection status by sex and host size showed that Sacculina serenei infection rate was higher in female crabs than male crabs, while infection intensity in male crabs was higher than female crabs. The prevalence and intensity of infection with Octolasmis angulata species increased significantly with host size. There was no statistical difference between the different host groups of sex and size. The data on parasitic crustaceans on Charybdis feriata contribute to the basis for the recovery, sustainable development of this endangered species.

This article investigates the effect of firm size on the performance of Vietnamese private enterprises. Based on the data from the Annual Enterprise Survey from 2009 to 2018, this study uses an ordinary least-squares regression model (OLS) to point out the effects of firm size (growth rate, total assets, and total labor) on the performance of Vietnamese private enterprises in both static and dynamic states. According to the results of the quantitative model, total assets are the biggest factor for determining firm performance, followed by total labor and growth rate. The results highlight the issue in Vietnamese private enterprises development in terms of scale, despite the fact that their number is growing, as the scale of enterprises decreases (the proportion of micro and small enterprises increases, but the proportion of medium and big enterprises decreases). Besides, the disadvantages of scale also negatively affect the development process of Vietnamese private enterprises, including accessing capital, increase in production or productivity, business expansion, and improving competitiveness. AcknowledgmentsThis research is supported by the National Science Project “Development of Private Enterprises in the Southwest Region in the new context” (KHCN-TNB/14-19/X15).

Mycobacterium tuberculosis contains diverse immunologically active components. This study investigated the biological function of a newly identified component, Rv1654, with the potential to induce apoptosis in macrophages. Recombinant Rv1654 induced macrophage apoptosis in a caspase-9/3-dependent manner through the production of reactive oxygen species (ROS) and interaction with Toll-like receptor 4. In addition, Rv1654 induced the production of tumor necrosis factor-α, interleukin-6, and monocyte chemoattractant protein-1 through the mitogen-activated protein kinase pathway. Furthermore, Rv1654-induced c-Jun N-terminal kinase (JNK) activation was inhibited by the ROS scavenger and Rv1654-induced apoptosis was inhibited by the JNK inhibitor. Moreover, it was found that treatment of macrophages with Rv1654 led to the loss of mitochondrial membrane potential, release of cytochrome c into the cytosol, and translocation of Bax into the mitochondria. Finally, Rv1654-mediated apoptosis was inhibited in macrophages transfected with Bax siRNA. These results suggest that Rv1654 induces macrophage apoptosis through a mitochondrial-dependent pathway and ROS-mediated JNK activation.

This is the first study on electrolytic oxidation of tapioca starch in the gelatinised state. Tapioca starch was first gelatinised and then oxidised in an electrolytic tank with NaCl as the electrolyte. The structural and physicochemical properties of the native and the oxidised starches were characterised by FTIR, XRD, molecular mass distribution, degree of oxidation, and thermal gravimetry. FTIR spectra and degree of oxidation analyses showed that 2 - 3% NaCl concentration in the electrolytic tank resulted in the highest content of carbonyl and carboxyl groups in the oxidised starch. The depolymerisation of starch increased with the concentration of NaCl. As a result of these structural changes, the thermal stability of starch samples decreased with the increase of NaCl concentration. The present work demonstrated a fast, simple, and benign process of oxidising starch that can be used in industrial production.

In this work, pyrolytic carbon electrodes were prepared through pyrolysis of well-patterned AZ 1505 positive photoresist films. The designed electrodes firstly were prepared via photolithography technique, then the polymer was thermally broken-down into carbon skeletons in an oxygen-free environment using pyrolysis technique. The effect of the highest temperature and ramping rate on the electrical properties of the carbon films were investigated. The results show that the pyrolysis process was optimal at the ramping rate of 3 °C/minute, annealing temperature of 900 °C, and annealing time of one hour. The lowest resistivity was obtained at 6.3 ´ 10-5 Wm for pyrolytic films prepared at the optimal pyrolysis conditions. Electrochemical measurements confirm the potential of this electrode for electrochemical sensing applications.

Provincial economic growth and development depend heavily on the improvement of infrastructure, for the latter is considered as a major constraint on doing business, especially in developing economies. It could be explained via the indicators of business economic density (World Bank, 2009). Some of these indicators, such as may reflects past performance, but it could not help to understand the pressure on maintaining the quality of infrastructure for economic activities of enterprises and households. The transport problem shows that there are some segments which have higher transport pressure than the other segments in the same type of infrastructure. The new point of this paper is that the authors build the selected mode of transportation index (SMT) in order to reflect the types of transport which are given priority service to use economic and social activities. This index also reflects the concentration and accumulation of economic activities and the density of them; therefore, it differs from the normal index of competitive advantage. It also means reflecting the competitive advantage of each locality in the region. In addition, this article focuses on assessing the impact of SMT on firm performance of enterprises through the case study of Vietnam.

Accurate identification at species level is vital for successful ichthyoplankton monitoring programs and management of important fish stocks. However, morphological identification can be difficult due to low interspecies variability, especially in the early stages as fish eggs and larvae. This study aims to apply DNA barcodes (16S rRNA and COI mtDNA) to identify Ichthyoplankton at Vung Tau coastal water, Southeast Vietnam. Ichthyoplankton samples were collected monthly from February to August, 2021. Sample collection in June and July was interrupted due to Covid 19 pandemic. A total of 28 species (of 41 DNA barcodes) from 13 families and 11 orders were identified, among which 13 species successfully identified to the species level. Two species (Sardinella gibbosa and Nemipterus furcosus) of eggs and larvae were shown to match with the adult fish barcodes. In this study, the group of dragonet fish exhibited diversity in species composition, and were found from February to May, however, no egg specimens were recorded. These significant findings have proven the efficiency of universal DNA barcoding in an ichthyoplankton surveys, serving as the basis for sustainable fishery resource management

DNA barcoding has proven a useful tool in marine species identification, especially, connecting the adults to early developmental stages such as planktonic larvae. Ichthyoplankton information plays an important role in fisheries management and conservation, especially in biodiversity hotspots, such as Vietnamese’s marine waters, where over 2000 species occur. This study collects Ichthyoplankton samples in Vung Tau waters, Southeast, Vietnam in 2020-2021. Egg and larval specimens were barcoded using the molecular markers (16S rRNA and COI mtDNA). In the total of over 50 specimens, 13 barcoded were successfully detected, and 15 species weren’t fully identified. Among that, only 2 species of eggs and larvae matched to the adult fish barcodes. The early developmental stages (eggs and larvae) of the goldstripe sardinella (Sardinella gibbosa) and fork-tailed threadfin bream (Nemipterus furcosus) were described. Sardine’s eggs were found in August, while larvae occurred in March. For N. furcosus, both eggs and larvae were recorded in April. These findings can support determining the spawning seasons and sites of marine fish species, as the basis for the management and conservation of marine resources.

Objectives: This study aimed to determine the antibiotic-resistant profile and to identify molecular characterization of some virulence genes of Klebsiella spp. isolated from mastitis samples in Vietnam. Materials and Method: A total of 468 samples from clinical mastitis cases were collected and submitted to the Laboratory. All samples were cultured, and Klebsiella spp. was identified through biochemical reactions and confirmed by Polymerase chain reaction (PCR). Antimicrobial resistance was tested by disk diffusion method, and virulence and resistance genes were tested by PCR. Results: An antibiogram study showed that a high proportion of isolates are multidrug-resistant (94%). All isolates were resistant to lincomycin and sulfamethoxazole, followed by ampicillin (94%), sulphonamide (66%), amoxicillin (56%), streptomycin (52%), polymyxin B (28%), colistin sulfate (12%), tetracycline (6%), ciprofloxacin (4%), florfenicol (4%), enrofloxacin (4%), piperacillin (2%), trimethoprim (2%), nalidixic acid (2%), imipenem (2%), and sulfamethoxazole/trimethoprim (2%). In contrast, all isolates showed sensitivity to gentamicin and ceftiofur. The appearance of an efflux pump system, extended-spectrum beta-lactamase (ESBL), tetracycline, and sulphonamides-resis¬tant genes was reconfirmed using different specific primers. Capsular serotype K1 and virulence genes magA, fimH, and entB, responsible for hypermucoviscosity production, adherence, and enterobactin production, were confirmed in isolates. Multidrug resistance and virulence potential in Klebsiella spp. are changing this mastitis pathogen into a superbug and making its management harder. Conclusions: Klebsiella spp. associated with bovine mastitis in Nghe An province were mostly multidrug-resistant and carried virulence genes including fimH, entB, and antimicrobials resistant genes (blaSHV, acrAKp, tetA, etc.), but these isolates were not ESBL producers.

Stress is inevitable in the modern life for people to make a living, however, prolonged stress will negatively affect their lives. This study, investigating impacts of stress on 986 university lecturers at The University of Danang, Viet Nam, used the PSS stress test to measure stress among participants. The results showed that there were a wide range of stressors for university lecturers, such as work-related problems, personal advancement, family relationships, work pressure, wages, and problems with friends. Our analysis showed that there were 176 lectures (39,9%) having signs of stress, of which 63 (15.1%) suffered high stress. Female lecturers suffered greater stress than their male colleagues. Based on our interview with those lecturers, we found that a better work policy such as increasing wages and reducing working hours can help reduce work-related stress. The paper highlighted the effects of stress on university lecturers’ performance as well as proposing solutions to reduce stress among university lecturers in Viet Nam.

Although Mycobacterium tuberculosis (Mtb) is an intracellular pathogen in phagocytic cells, the factors and mechanisms by which they invade and persist in host cells are still not well understood. Characterization of the bacterial proteins modulating macrophage function is essential for understanding tuberculosis pathogenesis and bacterial virulence. Here we investigated the pathogenic role of the Rv2145c protein in stimulating IL-10 production. We first found that recombinant Rv2145c stimulated bone marrow-derived macrophages (BMDMs) to secrete IL-10, IL-6 and TNF-α but not IL-12p70 and to increase the expression of surface molecules through the MAPK, NF-κB, and TLR4 pathways and enhanced STAT3 activation and the expression of IL-10 receptor in Mtb-infected BMDMs. Rv2145c significantly enhanced intracellular Mtb growth in BMDMs compared with that in untreated cells, which was abrogated by STAT3 inhibition and IL-10 receptor (IL-10R) blockade. Expression of Rv2145c in Mycobacterium smegmatis (M. smegmatis) led to STAT3-dependent IL-10 production and enhancement of intracellular growth in BMDMs. Furthermore, the clearance of Rv2145c-expressing M. smegmatis in the lungs and spleens of mice was delayed, and these effects were abrogated by administration of anti-IL-10R antibodies. Finally, all mice infected with Rv2145c-expressing M. smegmatis died, but those infected with the vector control strain did not. Our data suggest that Rv2145c plays a role in creating a favorable environment for bacterial survival by modulating host signals.

The identification of anomalies has become increasingly important for the security of sensory data gathering in the intelligent Internet of Things (iIoT). The current approaches might not be applied to the general cases of anomalies, i.e., both long-term and short-term anomalies, as well as not be suitable with real-time applications such as natural disaster monitoring and early warning systems. To address this challenge, this paper proposes a comprehensive approach, named DWT-PCA Anomaly Detection (DAD) to detect both long- and short-term anomalies. DAD bases on the combination of Discrete Wavelet Transform (DWT) and Principal Component Analysis (PCA) to improve the system performance. In particular, we first utilize the DWT to extract approximation coefficients and detail coefficients from the input data which are capable to highlight long-term and short-term anomalies, respectively. We then exploit the spatial-temporal correlation of neighboring sensors by applying PCA on these coefficients to obtain a high detection accuracy. Numerical experiments based on the real dataset of Intel Berkeley Research reveal that the proposed scheme obtains higher accuracy and a lower false-positive rate on detecting three typical anomalies: drift, noise, and outlier, comparing to existing schemes.

Beat sensor has shown its large potential to address issues of smart environment monitoring such as real time drought management. This paper presents an efficient temperature Beat sensor for energy efficient, long range smart monitoring systems by combining a new technique of Beat sensor with long range (LoRa) communication protocol. With the compact circuit size and the low energy consumption, the proposed sensor can be applied for Internet of Things based smart monitoring systems. The analysis and experimental results have clarified the advantages of the proposed temperature Beat sensor and its potential applications.

Mycobacterium tuberculosis (Mtb) is an intracellular pathogen known to persist in host cells. The apoptotic response of macrophages serves as a defense mechanism to inhibit the growth of intracellular bacteria, the failure of which can favor the spread of the pathogen to new cells. However, the mycobacterial components that regulate cell death and the related underlying mechanisms remain poorly understood. In this study, we investigated protein Rv3261, isolated from an Mtb culture filtrate, for its apoptotic potential using multidimensional fractionation. Rv3261 was found to induce macrophage apoptosis through the caspase-3/-9-dependent pathway. Furthermore, the ROS-dependent JNK activation pathway was found to be critical in Rv3261-mediated apoptosis. Rv3261 inhibited the growth of intracellular Mtb, which was significantly abrogated by pre-treatment with the ROS scavenger N-acetylcysteine (NAC), suggesting that Rv3261-mediated apoptosis may act as a host defense response. These findings suggest that Rv3261 is involved in the apoptotic modulation of Mtb-infected macrophages.

A research project to create a system for computing data from an active phased array antenna of a radar is considered. The system is implemented taking into account the delay in the arrival of a signal to each element of the array. The advantages and disadvantages of the proposed algorithm are considered.

Vietnamese words are combinations of consonants, vowels, and diacritics. Previous studies on Vietnamese spelling correction often focused on mistyped errors. Misspelled errors are more common and difficult to detect. Based on our literature review, there is no direct study to address this issue. A misspelled Vietnamese word can become another word does exist in the vocabulary but make the sentence a different meaning or meaningless. While mistyped errors are typographical errors, misspelled errors may appear in any type of text including typed documents and handwritten text. Compared to mistyped errors, misspelled errors are harder to detect, especially by people who type it out. This error comes from the wrong understanding about the spelling of the word. For that reason, checking a sentence with a vocabulary filter does not guarantee that the sentence is spelled correctly. Checking Vietnamese spelling errors is a difficult problem. There have been many articles trying to solve this problem with different approaches but they have their own limitations. In this paper, we propose a deep learning approach focusing on consonant misspell errors with superior accuracy compared to the existing methods. The accuracy of our model makes a significant gap compared to the current state-of-the-art model.

A research project to create an intelligent autonomous navigation system is being considered. The system is implemented on the basis of cognitive technologies and machine learning. The system makes a decision by analyzing the data of the optical system of computer vision.

The influence of sodium ion concentration [Na+] on the dissolution of carbohydrates in black liquor (BL) during flow-through kraft cooking of Scots pine wood meal (Pinus sylvestris) was studied. Fractions of BL were collected at different times and the carbohydrate content of the various fractions was analysed. Lignin was precipitated from the BL by lowering the pH, and the carbohydrate content of the precipitated lignins (Lprec) was also examined. The molecular weight distribution (MWD) of the Lprec samples was analysed. Xylose (Xyl) was found to be the most predominant sugar in BL aside from arabinose (Ara) and galactose (Gal), while the amounts of these sugars decreased with increasing levels of [Na+] in the cooking liquor. The minor amounts of mannose (Man) found in BL was not influenced by the [Na+]. The effects of NaCl and Na2CO3 on the carbohydrate dissolution were similar, but slightly lower concentrations of Ara and Xyl were found in the case of NaCl application. All of the Lprec samples contained some carbohydrate residues, the contents of which increased with increasing cooking time and decreased with higher [Na+]. It can be concluded that arabinoglucuronoxylan (AGX) along with arabinogalactans (AG) and arabinan, are covalently linked to lignin. The glucose (Glc) residue detected in Lprec may originate from 1,3-β-glucan linked to lignin.

Vietnam, is one of the developing countries, which approaches new technology, especially Internet is extremely fast approximately 67.1% in the population in 2017. With the boosting of information technology, it creates a new environment and tool to reach the customers' requirement. The new and effective method of narrowing the gap between the distributors and clients is electronic commerce (e-commerce). E-commerce is one of the most innovative expansions of the technologies that enable small and medium-sized enterprise (SMEs) access to global communication and trade. It can help SMEs expand their businesses to global market and increase sales, reduce costs as well as profits. In order to explore the impact of e-commerce as a novel way to boost the development in Vietnamese SMEs, this paper investigated the benefits and barriers of SMEs in e-commerce. Therefore, a questionnaire survey was conducted to study the impact of e-commerce on SMEs in Vietnam. From the results of this survey, we strongly believed that e-commerce is the main key to bring a lot of benefits to not only SMEs but also big companies in Vietnam.

Wood meal was submitted to kraft cooking in a small-scale flow-through reactor and the structural changes of lignin have been investigated. The rate determining steps in kraft cooking were in focus. Based on two-dimensional nuclear magnetic resonance (2D-NMR) measurements on lignin fractions extracted at different cooking times from the black liquor, it was observed that the main lignin reactions occur within 10–20 min and thus the kinetics of the chemical reaction cannot be the rate-determining step. On the other hand, the molecular weight (MW) of lignin is shifted towards larger fragments in the course of cooking time but the MW decreases with increasing ionic strength. Obviously, the kinetics of the delignification are strongly dependent on solubility and/or mass transport at the cell wall level. At chip size level, the mass transport of cooking chemicals into the wood chip may influence the overall kinetics in the initial part of the cooking. At longer cooking times the concentration of chemicals becomes sufficiently high in the wood chips, and the delignification is progressively governed by solubility and/or mass transport of lignin molecules occurring at the cell wall level.

The scope of this thesis spans the most recent advances in the investigation of chemical bonds of iridium-silicon complexes, in which a metal-bound silyl group behaves as a Z ligand that maintains a dative bond with the metal centre. This contrasts greatly with the case where this group behaves like an X ligand, that is where this silyl group binds to Ir through a covalent bond. Finally, and most interestingly are silylene ligands that in principle should establish a double bond with the Ir centre. The idea of evaluating and tuning the electrophilic character of the silyl moiety and adjuncts its “silylicity” was probed by experimental and theoretical means. To conduct that scheme, a broad range of metal–silane adducts and other metal–silyl complexes were investigated by the computation of metal–silyl interaction energies to outline the established tools that rationalize the bonding relationship that exists between the metal center and a SiR3 moiety. Also, this research revealed a clear separation between cases in which the Z character of the silyl moiety is the best description, and cases that belong to “classical” situations in which the X character dominates. Moreover, we postulated that for metal–silane adducts that possess a low intrinsic silylicity, a high “silylicity” can be triggered by ligand replacement or by changing in the charge of the complex.While working on this topic, we discovered that in the presence of tetrahydrofuran (THF), [(Ir-H)→SiRH2]+ adducts readily convert by H2 gas elimination at sub-ambient temperature into new THF-stabilized metallacyclic Ir(III)-"silylene" complexes. The emergence of metal silylene complexes via sequential H-Si activations followed by the spontaneous release of H2 featured in this thesis is unique. The primary goal of this thesis finally was to fully characterize those elusive complexes by NMR spectroscopy analyses and X-ray diffraction analysis. Furthermore, theoretical investigations (static DFT-D reaction-energy profiling, ETS-NOCV) and NMR kinetic studies were utilized to demonstrate the role of THF which facilitated H2 elimination. Coupled with silylene metal complex chemistry mentioned above, cationic iridacycle 1b is of interesting catalytic reactivity toward nitro arenes, which can perform the nitro reduction in arenes to give aniline type products.In crafting a new development of this chemistry, it is safe to hypothesize that cationic hydrido-Ir(III)-silylium species, whose catalytic reactivity is of significant correlation with the extend of polarization of the molecule can enhance in the key intermediates the molecule polarization, and therefore increase its catalytic reactivity. Such polarization that occurs already in the Ir-silane adduct stems from the electropositivity of Si centre. Keeping the main ligand backbone constant, introduction of a fluoro substituent can improve the polarization of the same molecule and by way of consequence increase its catalytic reactivity.As expected, F-1a also displays remarkable catalytic reactivity toward a benchmark test reaction that can be followed by piezometry, i.e. the O-dehydrosilylation of alcohols at room temperature with Et3SiH. A hydrido-Ir(III)-silylium intermediate crystal was trapped as well following on a reaction with Et2SiH. In conclusion, based on the discovery of hydrido-Ir(III)-silylium intermediates associated with a comprehensive study of their reactivity and catalytic performance, this thesis has taken steps to advance knowledge of Ir-silicon complexes by synthesis and the full structural characterization of notoriously elusive metal silylene complexes. Also, sophisticated computational methods have been employed to shed light on the mechanism of conversion of Ir-silane adducts into silylenes of which a great number were trapped by reactive recrystallization and subsequently characterized by X-ray diffraction analysis., Cette thèse englobe les avancées les plus récentes dans l'étude des liaisons chimiques des complexes iridium-silicium, dans lesquelles un groupe silyle lié à un métal se comporte comme un ligand Z qui maintient une liaison dative avec le centre du métal. Ceci contraste grandement avec le cas où ce groupe se comporte comme un ligand X, c’est-à-dire où ce groupe silyl se lie à Ir par une liaison covalente. Enfin, il est intéressant de noter que les ligands de silylène devraient en principe établir une double liaison avec le centre de l’Ir. L’idée d’évaluer et d’ajuster le caractère électrophile du fragment silyl et de sa ‘’silylicité” a été explorée de manière expérimentale et théorique. Pour mener à bien cette étude, une large gamme d'adduits métal – silane et d'autres complexes métal – silyl ont été étudiés par calcul des énergies d'interaction métal – silyl afin de définir la relation de liaison existant entre le centre métallique et une entité SiR3. En outre, cette recherche a révélé une séparation nette entre les cas dans lesquels le caractère Z du fragment silyl est la meilleure description, et les cas appartenant à des situations “classiques” dans lesquelles le caractère X domine. De plus, nous avons postulé que pour les adduits métal – silane qui possèdent une faible silylicité intrinsèque, une “silylicité” élevée peut être déclenchée par le remplacement du ligand ou par une modification de la charge du complexe. Tout en travaillant sur ce sujet, nous avons découvert qu'en présence de tétrahydrofurane (THF), les adduits [(Ir-H)→SiRH2]+ se convertissent facilement par élimination de H2 à une température sub-ambiante en un nouvel au complexe métallacyclique de ‘’silylene’’stabilisé par une molécule de THF. L'émergence de complexes silylène-métal via des activations séquentielles de liaison H-Si, suivies de la libération spontanée de H2 décrite dans cette thèse de doctorat, est unique. L'objectif principal de cette thèse était enfin de caractériser complètement ces complexes a priori insaisissables par des analyses par spectroscopie RMN et par analyse par diffraction des rayons X. De plus, des études théoriques (profil statique énergétique réactionnel déterminé DFT-D, ETS-NOCV) et des études cinétiques de RMN ont été utilisées pour démontrer le rôle du THF dans l’élimination de H2. Couplé à la chimie des complexes silylène métalliques mentionnés ci-dessus, l'iridacycle cationique 1b présente une réactivité catalytique intéressante vis-à-vis des nitro-arènes, qui peuvent effectuer la réduction du groupe nitro pour donner des produits dérivés de l’aniline.Il est raisonnable de supposer que la réactivité catalytique des espèces cationiques d'hydrido-Ir(III)-silylium, est en corrélation significative avec l'étendue de la polarisation de la molécule. Une telle polarisation qui se produit déjà dans le produit d'addition Ir-silan l'électropositivité du centre Si. En maintenant l’ossature du ligand principal constante, l’introduction d’un substituant fluoré augmente la polarisation de la même molécule et, par voie de conséquence, impacte sa réactivité catalytique. Comme on pouvait s'y attendre, F-1a présente également une réactivité catalytique remarquable vis-à-vis d'une réaction de test de référence pouvant être suivie par piézométrie, c'est-à-dire la O-déshydrosilylation d'alcools à la température ambiante avec Et3SiH. Un cristal de l’intermédiaire hydrido-Ir(III)-silylium a également été piégé à la suite d'une réaction avec Et2SiH.

Nanometer-sized luminescent semiconductor quantum dots (QDs) have been utilized as imaging and therapeutic agents in a variety of disease settings, including diseases of the central nervous system. QDs have several advantages over traditional fluorescent probes including their small size (5-10 nm), tunable excitation and emission spectra, tailorable surface functionality, efficient photoluminescence, and robust photostability, which are ideal characteristics for in vivo imaging. Although QDs are promising imaging agents in brain-related applications, no systematic evaluation of QD behavior in brain-relevant conditions has yet been done. Therefore, we sought to investigate QD colloidal stability, cellular uptake, and toxicity in vitro, ex vivo, and in vivo in the brain environment. We found that QD behavior is highly dependent on surface functionality and that treatment of cultured organotypic whole hemisphere (OWH) slices with QDs results in dose-dependent toxicity and metallothionein increase, but no subsequent mRNA expression level changes in inflammatory cytokines or other oxidative stress. QDs coated with poly(ethylene glycol) (PEG) were protected from aggregation in neurophysiologically relevant fluids and in tissue, allowing for greater penetration. Importantly, QD behavior differed in cultured slices as compared to monolayer cell cultures, and behavior in cultured slices aligned more closely with that seen in vivo. Irrespective of surface chemistry and brain-relevant platform, non-aggregated QDs were primarily internalized by microglia in a region-dependent manner both in slices and in vivo upon systemic administration. This knowledge will help guide further engineering of candidate QD-based imaging probes for neurological application.

The methods of adaptive and robust signal processing in the system of space-time coding are considered. The urgency of this problem in active radar installations and communication systems is shown.

Numerical solutions for inhomogeneous heat conduction problems in composite multilayer media are presented in the article. The proposed methods are adapted for solving on the basis of multi-core computing systems.

Network Function Virtualization (NFV) is one of the key technologies in 5G. It inherits virtualization technology in cloud computing and promises to bring many benefits for industry such as saving energy and reducing capital expenditure. Resource over-commitment is a significant technique of virtualization to fully utilize the resources of a cloud datacenter. Deploying VNFs with difference over-commitment ratios in an NFV datacenter leads to different results of the number of servers used and the order of VNFs placed in each physical server. This also affects Quality of Service (QoS) and energy consumption in the NFV datacenter. However, to the best of our knowledge, there has been no study to find exactly how much resource over-commitment is sufficient to meet the QoS while reducing the energy used in an NFV datacenter. In this paper, we analyze and evaluate the effect of CPU over-commitment ratio in VNF placement problem while considering the QoS and energy efficiency for NFV datacenters. After exhausting simulations, we have found out a proper value for CPU over-commitment ratio for NFV datacenters. By employing that ratio, an NFV datacenter could reduce up to 16.8% total power consumption compared with the others not using the over-provisioning technique.

The blue swimming crab, Portunus pelagicus (Linnaeus, 1758), is an economically important species. The presentation of epizoic pedunculate barnacles Octolasmis warwickii may cause difficulties for the growth and development of the host. In this article, we present the infestation status of O. warwickii on Portunus pelagicus in different studied areas, males and females and size-groups of crabs. A total of 180 individuals of Portunus pelagicus were examined (90 individuals in Khanh Hoa and 90 individual in Phu Yen included 100 females and 80 males). The results show that the infestation status of O. warwickii on Portunus pelagicus was not significant different between Khanh Hoa and Phu Yen. The prevalence of infestation in female crabs (29%) was significantly higher than in males (12.5%). The infestation varies between size groups; no infection was detected in < 80 mm crabs (both males and females); in female crabs, there was strong positive correlation between the size groups with prevalence (rs = 0.882) and mean intensity (rs = 0.669), while no correlation was observed between male size groups.

Recently, advances in technology have reduced the sizes, lowered prices, and increased commercial use of drones. In the market, drones have become an inexpensive and accessible way to accomplish many tasks such as filming, surveillance, agriculture, delivery, and broadcasting. Such applications typically require a video recording for their operations. However, due to the noise generated by propellers and rotors of a drone, the quality of sound in a video recorded by the drone is quite limited. In order to solve the noise problem of drones, this paper proposes a novel hybrid noise reduction technique combining Active Noise Control and Spectral subtraction methods. Experimental results show that the proposed technique produces a speech signal with up to 67.5% similarity to the original signal. It outperforms Active Noise Control and Spectral Subtraction with similarities of 53.1% and 39.6%, respectively.

With the development of mobile devices and the cloud, many kinds of offline services that people have been handling is replaced by online ones. In the past, Korean music cafe DJ performed the role of playing music requested and reciting the story of customers. We replace this offline service with an online one consisting of a public cloud, a streaming server, a streaming client, and a mobile device. The user requests music, video, and messages using the mobile, and receives services through a public screen and speakers in the space where the user is located. We also design and implement Cloud Media DJ platform. This paper focuses on the performance of this platform. We use Docker container distribution technology to accommodate large-scale traffic. In experimental evaluation results, the proposed platform reduces the response time from 25% (minimum) to 75% (maximum) according to the number of concurrent users compared to the existing one.

Content services have been provided to people in a variety of ways. Jukebox provides an automated music-playing service. User inserts a coin and presses a music button desired, the jukebox automatically selects and plays the record. DJs in Korean cafes receive the contents they want and play it through the speakers in the store. In this paper, we propose a service platform that reinvents the Korean cafe DJ in an integrated environment of IoT and cloud computing. In addition, we analyze the functional aspects of the services provided by the proposed platform. The user in a store requests contents (music, video, message) through the service platform. The contents are provided through the public screen and speaker in the store where the user is located. This allows people in the same location store to enjoy the contents together. The user information and the usage history are collected and managed in the public cloud. Therefore, users can receive customized services regardless of stores. Based on the implementation results of the platform, it is shown that the proposed platform provides more functions and advantages than other streaming services. Also proposed platform can provide contents efficiently to concurrent users.

The article overviews the results of research on the peculiarities of studies of the features of modeling chaotic systems using digital finite-accuracy systems with a fixed point for radar systems. The use of such models allows obtaining robust radar systems, as well as to study the dynamic properties of such systems. Electronic properties of such systems allow using them as a basis for powerful and high-frequency communication systems and other electronic devices whose characteristics are competitive in comparison with existing devices.