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This study explores the effects of child-external and child-internal factors on vocabulary skills of Vietnamese pre-schoolers. Thirty-nine Vietnamese children (54-77 months) were tested on vocabulary and cognition skills. Their parents completed a questionnaire on background information. Correlation and regression analyses were performed to explore the contribution of multiple factors to the variability in vocabulary skills. Results showed that the effects of multiple factors varied across modality and domain. Productive vocabulary was individually sensitive to more factors than receptive vocabulary; and phonologically-based vocabulary was more sensitive than semantically-based vocabulary. The strongest predictor of receptive vocabulary, productive vocabulary, semantically-based vocabulary and phonologically-based vocabulary was child intelligence, child pre-schooling length, household income and child age, respectively. The findings seem to support the multidimensional views of language with evidence that different domains or modalities of vocabulary skills respond to the effects of multiple factors differently; and components of verbal ability should be examined separately.

The ability to query and update over encrypted data is an essential feature to enable breach-resilient cyber-infrastructures. Statistical attacks on searchable encryption (SE) have demonstrated the importance of sealing information leaks in access patterns. In response to such attacks, the community has proposed the Oblivious Random Access Machine (ORAM). However, due to the logarithmic communication overhead of ORAM, the composition of ORAM and SE is known to be costly in the conventional client-server model, which poses a critical barrier toward its practical adaptations. In this paper, we propose a novel hardware-supported privacy-enhancing platform called Practical Oblivious Search and Update Platform (POSUP), which enables oblivious keyword search and update operations on large datasets with high efficiency. We harness Intel SGX to realize efficient oblivious data structures for oblivious search/update purposes. We implemented POSUP and evaluated its performance on a Wikipedia dataset containing ≥229 keyword-file pairs. Our implementation is highly efficient, taking only 1 ms to access a 3 KB block with Circuit-ORAM. Our experiments have shown that POSUP offers up to 70× less end-to-end delay with 100× reduced network bandwidth consumption compared with the traditional ORAM-SE composition without secure hardware. POSUP is also at least 4.5× faster for up to 99.5% of keywords that can be searched compared with state-of-the-art Intel SGX-assisted search platforms.

The Vietnamese government has issued several directives of lockdown in Hanoi, the capital city, for a month (1–30 April 2020) to prevent the human-to-human transmission of COVID-19. This action has affected air pollution due to a decline in transportation. Therefore, this study investigates spatial and temporal change in the PM2.5 concentrations during the first 4 months of 2020 in Hanoi metropolitan area. Spatial distribution maps of the PM2.5 concentration in Hanoi were provided for the first time. The average PM2.5 concentrations at the 22 air monitoring stations were strongly correlated with the population. April had a significantly lower level of PM2.5 than the other 3 months. In particular, the concentrations of PM2.5 and NO2 decreased by 12 and 54%, respectively, between March and April, especially at areas for commercial activities. In April, a higher level of PM2.5 was recorded between Tuesday–Thursday, which is a reverse trend with that in March. Furthermore, Monday and Friday did not show rush hour peaks for the PM2.5 levels in April. A decrease in the PM2.5 concentrations was partly influenced by the long-range transport from the outside to Hanoi. This study implies that a reduction in traffic volumes and public activities may possibly improve the air quality.

Long-term limestone quarry production planning is essential to maintain the supply to the cement plant. In which, quarry planners usually attempt to fulfil the complicated calculations, which ensure a consistent supply of raw materials to the cement plant while guaranteeing technical and operational parameters in mining. Traditionally, the calculations are done on a spreadsheet or by trial and error procedure resulting in high additive cost and an increase in product variability. Modern quarry management relies on block models and mathematical algorithms integrated into the software to optimize the long-term limestone quarry production planning. However, this method is potentially sensitive to geological uncertainty in block modelling, resulting in the deviation of the supply production of raw materials. The need for mining intelligently raw material is, therefore, crucial and an increasing issue in the cement industry. In this research, a new simulation and optimization software application called Quarrier is introduced, allowing quarry planners to address the conflicting requirements of long-term limestone quarry production planning while forecasting and mitigating the effects of geological uncertainty on the supply of raw materials for the cement plant. The benefits of this software are demonstrated through a limestone quarry in Vietnam.

In the years since its initiation, the software-defined network paradigm has evolved into a distinguished networking technology by causing a revolution in separating the control logic from physical devices and centralizing software-based controllers. Despite its indisputable benefits compared with the traditional network, the SDN raises the challenge of scalability with its physically centralized control. The only potential solution is to transform it into physically distributed SDN control. However, this solution requires the interoperability between SDN controllers, and the consistency of network state being distributed across these controllers. Although some east–west interfaces that help SDN controllers exchange network information have been released, they reveal several drawbacks. First, they cannot support a heterogeneous SDN system where SDN controllers are developed by different providers. Secondly, their consistency solution is simple in disregarding the tradeoff between the consistency level and the performance of SDN networks. This paper proposes an east–west interface, called SINA, to provide the interoperability of a heterogeneous and distributed SDN network. In addition, a novel reinforcement-learning-based consistency algorithm is introduced for an adaptive, quorum-based replication mechanism. The experimental results showed that SINA successfully connects heterogeneous and distributed SDN domains and balances the consistency and network performance.

Multi-user oblivious storage allows users to access their shared data on the cloud while retaining access pattern obliviousness and data confidentiality simultaneously. Most secure and efficient oblivious storage systems focus on the utilization of the maximum network bandwidth in serving concurrent accesses via a trusted proxy. How- ever, since the proxy executes a standard ORAM protocol over the network, the performance is capped by the network bandwidth and latency. Moreover, some important features such as access control and security against active adversaries have not been thoroughly explored in such proxy settings. In this paper, we propose MOSE, a multi-user oblivious storage system that is efficient and enjoys from some desirable security properties. Our main idea is to harness a secure enclave, namely Intel SGX, residing on the untrusted storage server to execute proxy logic, thereby, minimizing the network bottleneck of proxy-based designs. In this regard, we address various technical design chal- lenges such as memory constraints, side-channel attacks and scala- bility issues when enabling proxy logic in the secure enclave. We present a formal security model and analysis for secure enclave multi-user ORAM with access control. We optimize MOSE to boost its throughput in serving concurrent requests. We implemented MOSE and evaluated its performance on commodity hardware. Our evaluation confirmed the efficiency of MOSE, where it achieves approximately two orders of magnitudes higher throughput than the state-of-the-art proxy-based design, and also, its performance is scalable proportional to the available system resources.

In this paper, we extract quotations from Al Jazeera’s news articles containing keywords related to the COVID-19 pandemic. We apply Latent Dirichlet allocation (LDA), coherence measures, and clustering algorithms to unsupervisedly explore latent topics from the dataset of about 3400 quotations to see how coronavirus impacts human beings. By combining noun phrases as inputs before the training and Cv measure for coherence values, we obtain an average coherence value of 0.66 with a least average number of topics of 24.8. The result covers some of the top issues that our world has been facing against the COVID-19 pandemic.

The majority of sensors have played a vital role in the autonomous vehicle area. In this research, a dynamic model for measuring a characteristic of the analog sensor is developed, the shape of the output signal is a critical factor in road identification of autonomous vehicles. By hand-made testing system is built successfully, a number of alloys and non-magnetic metals (Aluminium and Copper) are considered in every aspect of them. In addition, the comparison experimental outcomes between various dynamic models prove that, with the same metal size (50 × 20), and sensing distance (6 mm), the shape of the output signal of measuring is similar. These results are distinguished clearly with alloys. Signal interference will also be minimized due to the control of the movement speed of the sensor. This is an integral element for approaching road of mobile devices with different obstacles.

Objectives: we aimed to assess the levels of plasma ADMA in end stage renal disease (ESRD) patients without dialysis and its association with cardiovascular risk factors. Materials and Methods: This is a controlled cross-sectional study. Plasma ADMA level and other variables were measured in 30 patients of ESRD without dialysis and in 30 control healthy persons. Plasma ADMA levels were determined by enzyme linked immunosorbent assay (ELISA) using kits provided by immunodiagnostic AG, Germany. Data was analyzed by SPSS 19.0. Results: Mean level of ADMA in ESRD patients was 0.88 ± 0.27 µmol/L. Mean level of ADMA in healthy people was 0.49 ± 0.13 µmol/L, with significiant difference (p

Objectives: we aimed to assess the levels of plasma ADMA in healthy people and in reserved patients with end stage renal disease (ESRD), the association between plasma ADMA with serum creatinine concentration and with eGFR. Materials and Methods: This is a controlled cross sectional study. Plasma ADMA and other variables were measured in 27 patients with ESRD and in 21 controls. Plasma ADMA levels were determined by enzyme linked immunosorbent assay (ELISA) using kits provided from immunodiagnostic AG, Germany. Data was analyzed by SPSS 19.0. Results: Mean ADMA in men- women was 0.69 ± 0.19 µmol/L and 0.61 ± 0.20 µmol/L, respectively, (p>0.05), mean ADMA in control and disease were 0.48 ± 0.17 µmol/L and 0.77± 0.12µmol/L; respectively, (p

Dynamic Searchable Symmetric Encryption (DSSE) allows to delegate keyword search and file update over an encrypted database via encrypted indexes, and therefore provides opportunities to mitigate the data privacy and utilization dilemma in cloud storage platforms. Despite its merits, recent works have shown that efficient DSSE schemes are vulnerable to statistical attacks due to the lack of forward-privacy, whereas forward-private DSSE schemes suffers from practicality concerns as a result of their extreme computation overhead. Due to significant practical impacts of statistical attacks, there is a critical need for new DSSE schemes that can achieve the forward-privacy in a more practical and efficient manner. We propose a new DSSE scheme that we refer to as Forward-private Sublinear DSSE (FS-DSSE). FS-DSSE harnesses special secure update strategies and a novel caching strategy to reduce the computation cost of repeated queries. Therefore, it achieves forward-privacy, sublinear search complexity, low end-to-end delay, and parallelization capability simultaneously. We fully implemented our proposed method and evaluated its performance on a real cloud platform. Our experimental evaluation results showed that the proposed scheme is highly secure and highly efficient compared with state-of-the-art DSSE techniques. Specifically, FS-DSSE is up to three magnitude of times faster than forward-secure DSSE counterparts, depending on the frequency of the searched keyword in the database.

Hybrid mesoporous materials as carriers for immobilization of D-amino acid oxidase (DAAO) were prepared via three steps: (i) hydrothermal synthesis of nanoporous MCF, SBA-15 and MCM-41 powders, (ii) functionalization with 3-aminopropyltriethoxysilane (APTES) by post-synthesis grafting; and (iii) activation with glutardialdehyde. The resulting mesostructured solids were characterized by various techniques: XRD, IR, TGA-DTA and N2 adsorption–desorption (BET). The characterization results indicated that these materials still maintained their structure after functionalization. IR data and TGA-DTA analysis demonstrated the existence of amine functional groups on the surface of APTES-functionalized samples. The DAAO immobilized on these materials exhibited higher catalytic activity and stability of enzyme for conversion of cephalosporin C (CPC) as compared to those of the non-functionalized ones. The catalytic activity and stability of enzyme decreased in the order MCF > SBA-15 > MCM-41.

Background CD31 is a key transmembrane neutrophil immunoregulatory receptor. Mesenteric ischemia/reperfusion-induced neutrophil activation leads to a massive cleavage and shedding of the most extracellular domains of CD31 into plasma, enhancing the deleterious effect of neutrophil activation. We have evaluated the preventive therapeutic potential of an engineered synthetic octapeptide (P8RI), which restores the inhibitory intracellular signaling of cleaved CD31, in an experimental model of acute mesenteric ischemia/reperfusion. Methods In a randomized, controlled, and experimenter-blinded preclinical study, mesenteric ischemia/reperfusion (I/R) was induced in Wistar rats by superior mesenteric artery occlusion for 30 min followed by 4 h of reperfusion. Three groups of rats were compared: I/R + saline perfusion (I/R controls group, n = 7), I/R + preventive P8RI perfusion (P8RI group, n = 7), and sham-operated rats + saline perfusion (sham group, n = 7). Results Compared with I/R controls, P8RI perfusion significantly decreased intestinal ischemia/reperfusion injury (Chiu’s score, P = 0.01; epithelial area, P = 0.001) and bacterial translocation (plasma Escherichia coli DNA, P = 0.04) and could limit intestinal bleeding (P = 0.09). P8RI decreased neutrophil activation assessed by matrix metalloproteinase-9 release in plasma (P

Dynamic Searchable Symmetric Encryption (DSSE) allows search/update operations over encrypted data via an encrypted index. However, DSSE has been shown to be vulnerable to statistical inference attacks, which can extract a significant amount of information from access patterns on encrypted index and files. While generic Oblivious Random Access Machine (ORAM) can hide access patterns, it has been shown to be extremely costly to be directly used in DSSE setting. By exploiting the distributed cloud infrastructure, we develop a series of Oblivious Distributed DSSE schemes called ODSE, which enable oblivious access on the encrypted index with a high security and improved efficiency over the use of generic ORAM. Specifically, ODSE schemes are 3x-57x faster than applying the state-of-the-art generic ORAMs on encrypted dictionary index in real network settings. One of the proposed ODSE schemes offers desirable security guarantees such as information-theoretic security with robustness against malicious servers. These properties are achieved by exploiting some of the unique characteristics of searchable encryption and encrypted index, which permits us to harness the computation and communication efficiency of multi-server PIR and Write-Only ORAM simultaneously. We fully implemented ODSE and have conducted extensive experiments to assess the performance of our proposed schemes in a real cloud environment.

Oblivious Random Access Machine (ORAM) enables a client to access her data without leaking her access patterns. Existing client-efficient ORAMs either achieve O(log N) client-server communication blowup without heavy computation, or O(1) blowup but with expensive homomorphic encryptions. It has been shown that O(log N) bandwidth blowup might not be practical for certain applications, while schemes with O(1) communication blowup incur even more delay due to costly homomorphic operations. In this paper, we propose a new distributed ORAM scheme referred to as Shamir Secret Sharing ORAM (S3ORAM), which achieves O(1) client-server bandwidth blowup and O(1) blocks of client storage without relying on costly partial homomorphic encryptions. S3ORAM harnesses Shamir Secret Sharing, tree-based ORAM structure and a secure multi-party multiplication protocol to eliminate costly homomorphic operations and, therefore, achieves O(1) client-server bandwidth blowup with a high computational efficiency. We conducted comprehensive experiments to assess the performance of S3ORAM and its counterparts on actual cloud environments, and showed that S3ORAM achieves three orders of magnitude lower end-to-end delay compared to alternatives with O(1) client communication blowup (Onion-ORAM), while it is one order of magnitude faster than Path-ORAM for a network with a moderate bandwidth quality. We have released the implementation of S3ORAM for further improvement and adaptation.

Background/Objectives: Acoustic radiation force impulse (ARFI) is a novel non-invasive technology for the assessment of liver fibrosis. Some studies previously reported that ARFI is a promising method for assessing liver fibrosis. Aspartaste aminotransferase (AST) to platelet ratio index (APRI) has been proposed as an easily determined and quite accurate noninvasive marker of liver fibrosis. This study aimed to explore the value of liver fibrosis assessment by ARFI, APRI and their combination in patients with chronic hepatic disease. Patients and Methods: The study was carried out on 119 patients with chronic hepatitis B, C, alcoholic liver disease and NASH. All of patients underwent a liver biopsy for histological assessment of liver fibrosis, ARFI elastography and calculate APRI. Cut-off values were determined using receiver-operating characteristic (ROC) curves. The corresponding cut-off values, sensitivities (Se), specificities (Sp), positive predict value (PPV) and negative predict value (NPV) were calculated and compared. In addition, the correlation of liver fibrosis stages with SWV and APRI were also tested to evaluate significant data. Results: Histological liver fibrosis was evaluated by Metavir scoring; F0: 9 cases, F1: 57 cases, F2: 23 cases, F3: 19 cases and F4: 11 case. SWV correlated significantly with the fibrosis stage (Spearman rho: 0.69, p =

Authentication systems using gait captured from inertial sensors have been recently developed to enhance the limitation of existing mechanisms on mobile devices and achieved promising results. However, most these systems employed pattern recognition and machine learning techniques in which biometric templates are stored insecurely, which could leave critical security and user privacy issues. Specifically, a compromise of original gait templates could result in everlasting forfeiture. In this paper, two main results will be presented. Firstly, we propose a novel gait authentication system on mobile devices in which the security and privacy are preserved by employing a fuzzy commitment scheme. Instead of storing original gait templates for user verification like in conventional approaches, we verify the user via a stored key which is biometrically encrypted by gait templates collected from a mobile accelerometer. Secondly, the discriminability of sensor-based gait templates are investigated to determine appropriate parameter values to construct an effective gait-based biometric cryptosystem. The performance of our proposed system is evaluated on the dataset including gait signals of 34 volunteers. We achieved the zeroFAR and the False Rejection Rate of approximately 16.18 % corresponding to the key length, as well as the system security level of 139 bits. The results from our experiment show that accelerometer-based gait could be further investigated to construct a biometric cryptosystem, as effective as other biometric traits such as iris, fingerprint, voice, and signature.

Background: Transient elastography (FibroScan) is a novel, noninvasive, safe and rapid bedside method, in assessement the liver stiffness in chronic hepatitis. Aims: To assess the degree of liver fibrosis in the chronic hepatitis patients in comparison with liver biopsy performed at the same time. Methods: We studied 66 consecutive patients with chronic hepatitis, in which liver stiffness was measured by FibroScan and liver biopsy was performed in the same session (assessed according to the Metavir score). Results: FibroScan values ranged from 3.8 to 75 kiloPascal (median, 16.46 kPa). According to the Metavir score of the 66 patients: 22,1% had F0 and F1, 12 had F2, 16.6% had F3 and 43,9% had F4. The mean values of liver stiffness in patients were: F0 & F1: 5.35 ± 2.73 kPa; F2: 8.59 ± 3.37 kPa; F3: 12.45 ± 4.69 kPa; F4: 32.44 ± 18.52 kPa. There were the significant positive correlation between the liver stiffness measured by FibroScan and liver biopsy (r = 0.6, p < 0.05). Conclusions: FibroScan is a simple and effective method in assessing liver fibrosis. The liver fibrosis measured by FibroScan was well correlated with the degree of liver fibrosis by Metavir index, serum albumin, bilirubin, AST, platelet, INR in chronic hepatitis. Keywords: Chronic hepatitis, Fibrosis, Transient elastography, Liver biopsy

Background/Objectives: Acoustic radiation force impulse (ARFI) is a novel non-invasive technology for the assessment of stages of liver fibrosis in chronic hepatic disease. Some studies previously reported that ARFI is a promising method for assessing liver fibrosis in patients with NAFLD/NASH. This study aimed to validate the diagnostic usefulness of ARFI for prediction of staging of liver fibrosis in patients with NASH. Patients and Methods: The study was carried out on 51 patients with NASH. All of patients underwent a liver biopsy for histological assessment of liver fibrosis and ARFI elastography. Cut-off values were determined using receiver-operating characteristic (ROC) curves. Results: Histological liver fibrosis was evaluated by Metavir scoring; F0: 8 cases, F1: 29 cases, F2: 10 cases and F3: 4 cases. ARFI quantification correlated significantly with the fibrosis stage (Spearman rho: 0.44, p

Background: Peptic ulcer bleeding is one of the common medical emergencies with a high rate of mortality. Endoscopic hemostasis with HSE 3% injection is an effective treatment for patients with peptic ulcer bleeding, helps to save cost and avoid an unnecessary emergency surgery. Objective: To determine the success rate of endoscopic hemostatic with HSE 3% injection in patients with peptic ulcer bleeding. Patients and methods: A prospective, cross sectional study on 41 patients with peptic ulcer bleeding admitted in Can Tho Central General Hospital, from August 2012 to April 2013. All the patients underwent emergency endoscopy for hemostasis by injecting HSE 3% solution, and high- dose PPI use. Results: The rate of Forrest class IA, IB, IIA, IIB was 12.2%, 56.1%, 19.5% and 12.2%, respectively. The rate active bleeding group (Forrest class IA/IB) was 668.3%, while hemostatic group with high risk of rebleeding was 31.7%. The success rate was 92.7%, and the rebleeding rate was 7.3%. Conclusion: Endoscopic HSE 3% injection combined with high- dose PPI is an effective, relatively safe treatment for peptic ulcer bleeding. Key words: peptic ulcer bleeding, HSE, endoscopic hemostasis therapy.

In this research, a smart transportation system integrated with a management system of highly distributed communication network for Personal Rapid Transit (PRT) was designed. The Personal Rapid Transit (PRT) system is a new and easy-to-use transportation solution for 1–4 persons to destination directly. PRT system offers great potential for becoming a common transportation system in the future involving driverless vehicles, ride comfort and collision warning with low construction cost and operation cost. In PRT system, two important functions are automatic driverless control and crossway merging control. To have safe and smooth merging operation in automated vehicle systems for PRT, a merging management system is necessary. Our work proposed a new merging management system related to distributed traffic control, new locating method and safe dynamic headway. In this system, an efficient car communication was built based on the vehicle-to-vehicle (V2V) wireless protocol and highly distributed control. In order to determine the car location, RFID technique is used in the system. A new buffer-zone strategy and fuzzy logic control are two efficient vehicle-merging algorithms that are required for dynamic determination of the merging sequence for all cars in a Y-intersection. From simulation results, it was found that cruise distance can be safely kept from each car to its front car and each car can merge into mainline smoothly gently and efficiently.

Additional file 5. Provider antimalarial/malaria rapid diagnostic test stock form.

Gait has been considered as an efficient biometric trait for user authentication. Although there are some studies that address the task of securing gait templates/models in gait-based authentication systems, they do not take into account the low discriminability and high variation of gait data which significantly affects the security and practicality of the proposed systems. In this paper, we focus on addressing the aforementioned deficiencies in inertial-sensor based gait cryptosystem. Specifically, we leverage Linear Discrimination Analysis to enhance the discrimination of gait templates, and Gray code quantization to extract high discriminative and stable binary template. The experimental results on 38 different users showed that our proposed method significantly improve the performance and security of the gait cryptosystem. In particular, we achieved the False Acceptant Rate of \(6\times 10^{-5} \%\) (i.e., 1 fail in 16983 trials) and False Rejection Rate of \(9.2 \%\) with 148-bit security.

Background: Gastrointestinal bleeding in general and gastrointestinal bleeding from peptic ulcer is the most common internal medical emergency especially in digestive diseases. The evaluation of rebleeding is important problems in treatment and prognosis. Thereby improving the quality of treatment and reduce the dead rate for patients, the Blatchford score is a screening tool to evaluate patients gastrointestinal bleeding that help for the medical intervention such as blood transfusion, endoscopic therapy or surgical hemostasis or not. Objectives: 1. Investigating the mean value of Blatchford score according to the location, the causes and the severity of bleeding and the type of lesions by the Forrest’s classification. 2 Comparising the value of Blatchford score with Rockall score in prognosis of the upper gastrointestinal bleeding due to. Subjects and Methods: Prospective cohort study of 101 patients with gastrointestinal bleeding due to gastroduodenal disease treated at Hue Central Hospital from 12/ 2011 to April 2013. The data were processed by SPSS ver 19.0. Results: The average Blatchford patient group 7.91 ± 3.81 research, medical interventions accounted for 60.40 %. Lesions in the stomach Blatchford average 7.37 ± 4.12, duodenum 9.13 ± 4.16, lesions both gastroduodenal 8.52 ± 2.23. Blatchford point average of group causes ulcers 8.48 ± 3.74, ulcerative colitis with a 8.46 ± 3.13, inflammation 5.83 ± 4.20. Blatchford point average of group severe hemorrhagic 10.20 ± 2.10 points, just 8.04 ± 3.67 hemorrhage, minor hemorrhage 3.37 ± 2.48, Blatchford point average of at risk groups Forrest high point of 10.08 ± 3.57, 7.59 ± Forrest low risk of 3.76 points, - Percentage of patients Blatchford score > 6 / patient Blatchford score ≤ 6, in both gastric lesions and duodenal lesions is higher than a position or in the stomach or duodenum) and in duodenum were higher in the stomach (10.49/1 from 3/1 and 1.82/1); Blatchford score of ulcerative lesions was higher than that of purely inflammatory lesions; Level Blatchford bleeding score as high as heavy. The difference is statistically significant with p < 0.01; Forrest high risk group Blatchford score higher than low risk - Blatchford scoring higher sensitivity Rockall score (91.80% against 77.05%). The positive predictive value of Blatchford score higher than Rockall score (76.71% compared with 73.44%). Conclusion: The average Blatchford's research group patients 7.91±3.81; Ulcerative lesions with higher points Blatchford merely inflammatory lesions; Level Blatchford bleeding score higher the more severe; Forrest high risk group Blatchford score higher than low risk; Rockall and Blatchford scoring system is valuable in prognostic evaluation requires medical intervention. Blatchford scoring higher sensitivity Rockall score. Keywords: Gastroduodenal disease, Blatchford score, gastrointestinal bleeding

Staging of hepatic fibrosis is crucial for prognosis, surveillance and treatment decision in patients with chronic liver diseases in clinical practice. Liver biopsy has still the gold standard for assessment of hepatic fibrosis, but it has some limitations. To overcome this, non-invasive methods were developed. The methods of noninvasive assessment of liver fibrosis were divided into two main groups: serum biomarkers and techniques measuring liver stiffness. Each method has its own advantages and limits. Some studies suggest that the effectiveness of noninvasive methods for assessing liver fibrosis may increase when they are combined. The aim of this article is to review and update the different non invasive methods for assessment of hepatic fibrosis, their advantages, disadvantages, diagnostic accuracy and their applications in clinical practice. Key words: hepatic fibrosis, liver stiffness, chronic liver disease

Aims: Apply different silvicultural approaches to improve oil productivity and quality from abandoned stands and analyze cost-benefit of developing tea oil camellias. Study Design: Three experiments were conducted as (1) Changing canopy of 36-yearold plantation by grafting, (2) Using Bortrac fertilizer for promoting fruiting by spraying to canopy, and (3) Stem/branch thinning and fertilizing. Place: North Central, Vietnam at 19o16’N and 105o23’E. Methodology: Shoots of 4 – 6 mm in diameter and 3 -5 cm long from improved cultivar were used to graft to 36-year-old trees. Bortrac fertilizer was used to spray to canopy of 15-year-old plantation when trees bloomed. While three treatments of stem/branch thinning and fertilizing at different intensities was applied to 29-year-old plantation of 830 trees ha. Results: The results showed that old stand, which has low seed productivity, could be replaced by a new canopy through grafting with improved cultivars. Meanwhile, fertilizing through spraying on canopy at early blooming peak with Bortrac fertilizer increased seed Original Research Article Thang et al.; AJAEES, Article no. AJAEES.2014.001 2 productivity by 28%. In addition, applying 0.5 kg inorganic fertilizer (NPK) and 5 kg organic manure per tree coupled with thinning under crown-old branches and diseased branches increased up to 60% seed productivity and improved oil ratio and quality. Costbenefit analysis indicated that by applying different intensities of stem/branch thinning and fertilizing to 29-year-old plantation, profit margin increased from US$ 502 to as much as US$ 549 ha year for growers selling dry seeds as final product. Meanwhile, it increased from US$ 1,791 to US$ 2,426 ha year by extracting oil for final product. Conclusion: There is a potentiality of growing tea oil camellia with the increased profit of as much as US$ 2,426 ha year for 29-year-old plantation by applying intensive silvicultural approach.

Background: Peptic ulcer bleeding is one of the common emergency cases in gastroenterology, the mortality rate is high. The study of the effecacy of hemoclip in endoscopic hemostasis therapy that helps to give an effective method for treatment peptic ulcer bleeding, to save cost for patients, to avoid a surgery that is serious for these patients. Objective:(i) To determine the prevalence of peptic ulcer bleeding with high risk of rebleeding (FIA, FIB and FIIA) according to Forrest classification; (ii) To determine effecacy of hemoclip in endoscopic hemostasis in patients with peptic ulcer bleeding. Patients and methods:A cross sectional study on 22 patients with peptic ulcer bleeding in Can Tho Center General Hospital during May 2012 to October 2013. Results:The rate of active bleeding group (Forrest type IA and IB) and visible vessel group (Forrest type FIIA) were 50% and 50%. Hemostatic rate by clipping was 95.5%, and the rebleeding rate was only 9.1%; the rate of emergent surgery and mortality were 4.5% and 4.5%. Conclusion:Endoscopic hemoclip treatment for bleeding due to peptic ulcer is an effective and safe method. The percentage of success was high 95.5%. The rebleeding rate was low, only 9.1%. The number of patients haved been operated and the dead rate were low, only 4.5%. Key words: Peptic ulcer bleeding, hemoclip, endoscopic hemostasis therapy

Dynamic Searchable Symmetric Encryption (DSSE) allows a client to perform keyword searches over encrypted files via an encrypted data structure. Despite its merits, DSSE leaks search and update patterns when the client accesses the encrypted data structure. These leakages may create severe privacy problems as already shown, for example, in recent statistical attacks on DSSE. While Oblivious Random Access Memory (ORAM) can hide such access patterns, it incurs significant communication overhead and, therefore, it is not yet fully practical for cloud computing systems. Hence, there is a critical need to develop private access schemes over the encrypted data structure that can seal the leakages of DSSE while achieving practical search/update operations. In this paper, we propose a new oblivious access scheme over the encrypted data structure for searchable encryption purposes, that we call Distributed Oblivious Data structure DSSE (DOD-DSSE). The main idea is to create a distributed encrypted incidence matrix on two non-colluding servers such that no arbitrary queries on these servers can be linked to each other. This strategy prevents not only recent statistical attacks on the encrypted data structure but also other potential threats exploiting query linkability. Our security analysis proves that DOD-DSSE ensures the unlink-ability of queries and, therefore, offers much higher security than traditional DSSE. At the same time, our performance evaluation demonstrates that DOD-DSSE is two orders of magnitude faster than ORAM-based techniques (e.g., Path ORAM), since it only incurs a small-constant number of communication overhead. That is, we deployed DOD-DSSE on geographically distributed Amazon EC2 servers, and showed that, a search/update operation on a very large dataset only takes around one second with DOD-DSSE, while it takes 3 to 13 minutes with Path ORAM-based methods.

Phone segmentation is to divide a continuous speech signal into discrete, non-overlapping phone units. In this paper, a blind method for phone segmentation without using prior knowledge of speech content is proposed. A two-step algorithm for detecting phone boundaries is derived. The first step selects peaks of Euclidian curve as phone boundary candidates. The second step verifies these candidates using Gaussian function. The Gaussian function is computed locally. Therefore, it is suitable for speech feature at each local region of the utterance. Experiments show that our method is good for both short and long speech. Experiment 1 is conducted on a short speech corpus, the TIMIT. Our results are comparable to or more accurate than those of previous methods. Experiment 2 is conducted on a long speech corpus, the TCC300. Our results are more accurate than previous method. The relative improvement of F-value is 1.05%. This method is effective for long speech.