263 research outputs found

    SYNTHESIS OF STARCH MODIFIED MONTMORILLONITE AS AN EFFECTIVE ADSORBENT FOR Pb (II) REMOVAL FROM WATER

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    The adsorbent is prepared by the montmorillonite co-modification with starch for the removal of Pb (II) ions from aqueous solution. The Fourier-transformed infrared (FTIR), X-ray diffraction (XRD) spectroscopies were used to determine the structure and characteristics of the adsorbent. The main factors affecting the removal of Pb (II) ions were investigated, including the effect of pH, contact time, adsorbent dosage and the initial concentration of Pb (II). Batch process can be used for adsorption and equilibrium studies. The experimental data were fitted using Freundlich and Langmuir adsorption models. The Langmuir isotherm best fitted the experimental data with R2 0.99 and maximum Pb (II) adsorption capacity of 21.5 mg/g indicated monolayer adsorption. Kinetic studies using pseudo-first-order and pseudo-second-order rate models showed that the process complied well with the pseudo second-order rate model

    Abietane diterpenoids and neolignans from the roots of Pinus kesiya

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    The phytochemical investigation of the ethyl acetate extract of Pinus kesiya Royle ex Gordon roots led to the isolation of two abietane diterpenes, 7-oxo-15-hydroxy-dehydroabietic acid (1) and dehydroabietic acid (2) as well as two neolignans, cedrusin (3) and cedrusin-4-O-β-D-glucopyranoside (4). Their structures were determined by combination of spectral analysis and comparison with reported data. Among them, compound 1 was isolated from the genus Pinus for the first time. Keywords. Pinus kesiya, abietane diterpenes, neolignans, dehydroabietic acid, cedrusin

    Giant compound odontoma of the mandible in an adolescent

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    Abstract Odontomas are one type of benign odontogenic hamartoma that includes the compound and complex odontoma. They are generally reported not to exceed 3 cm in diameter. Odontomas with a diameter exceeding 3 cm are considered giant odontomas. An accurate diagnosis of odontomas cannot be made during the clinical examination. The majority of compound odontoma is diagnosed most commonly during radiographic screening. It should be done in coordination with a histological examination after surgical treatment. We report a case of giant compound odontoma of the mandible in a young boy. The tumor is treated by surgical excision under general anesthesia

    Ecpoc: an evolutionary computation-based proof of criteria consensus protocol

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    Recently, blockchain technology has been applied in many domains in our life. Blockchain networks typically utilize a consensus protocol to achieve consistency among network nodes in a decentralized environment. Delegated Proof of Stake (DPoS) is a popular mechanism adopted in many networks such as BitShares, EOS, and Cardano because of its speed and scalability advantages. However, votes that come from nodes on a DPoS network tend to support a set of specific nodes that have a greater chance of becoming block producers after voting rounds. Therefore, only a small group of nodes can be selected to become block producers. To address this issue, we propose a new protocol called Evolutionary Computation-based Proof of Criteria (ECPoC), which uses ten criteria to evaluate and select a new block procedure in each round. Next, a set of optimal weights used for maximizing the network’s decentralization level is identified through the use of evolutionary computation algorithms. The experimental results show that our consensus significantly enhances the degree of decentralization in the selection process of witness nodes compared to DPoS. As a result, ECPoC facilitates fairness between nodes and creates momentum for blockchain network developmen

    Chemical composition and antibacterial activities of essential oils from fruits of Melicope pteleifolia (Champ. Ex Benth.) T.G. Hartley grown in Lam Dong Province, Vietnam

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    In the present study, chemical composition and antibacterial properties of essential oil obtained from the aerial parts of the Melicope pteleifolia (Champ. ex Benth.) T.G Hartley in Dalat were evaluated. Essential oil was isolated through hydro-distillation. Twenty-nine constituents comprising 100% of the essential oil were characterized by gas chromatography/mass spectrometry (GC-MS) techniques. The major compounds in the essential oil were (+)-Sabinene (34.73%), Cis-α-bergamotene (13.15%), Z-α-trans-bergamotol (5.28%), β-mycrene (4.98%), and 1,3,6-octatriene, 3,7-dimethyl-(4.71%). Antibacterial activities of Melicope pteleifolia essential oil were investigated against Gram-positive and-negative bacteria. Results showed significant activities against Streptococcus pyogenes and Escherichia coli using an agar well diffusion method. The application of this essential oil in preventing and eliminating bacteria could be useful in fields as medicine and cosmetics.

    10-Year Cardiovascular Risk in Hypertensive Patients: Insights from Central Vietnam Using WHO 2019 Chart

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    Background: Assessing the 10-year cardiovascular disease (CVD) risk is crucial for effective prevention and management. Despite its significance, information is limited on CVD risk among hypertensive patients in primary care in Central Vietnam. We conducted this study to estimate 10-year CVD risk in primary care settings and explore its associated risk factors, using the 2019 WHO CVD risk chart. Methods and Results: This cross-sectional study collected socio-demographic and clinical data through a standardized questionnaire. Cardiovascular risk was estimated using the WHO CVD risk charts for Southeast Asia. The prevalence of low, moderate, and high CVD risk was 52.1%, 38.9%, and 9.0%, respectively. Notably, men had significantly higher rates of moderate (48.6%) and high (17.6%) CVD risk than women (31.4 and 2.4%, respectively) (P=0.000). Age was a significant factor, with an increasing prevalence of moderate and high CVR as age advanced. Specifically, the 50-59 age group had a moderate risk of 18.6%, rising to 69.9% in the 70-74 age group. High CVD risk increased from 0.6% to 27.6% in the same age groups. Lower educational levels were associated with a higher proportion of moderate CVD risk. Smoking and excessive alcohol consumption were linked to elevated CVD risks (25.0% and 30.0%, respectively), surpassing those without these behaviors. Similar trends were observed for individuals with diabetes, high total cholesterol, and high blood pressure. Conclusion: Approximately one-tenth of hypertensive patients face a high risk of developing CVDs within the next 10 years. A comprehensive approach, encompassing behavioral changes and the management of metabolic risk factors, is essential to reduce CVD risk effectively

    Covid-19 vaccines production and societal immunization under the serendipity-mindsponge-3D knowledge management theory and conceptual framework

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    Since the outbreak of the Coronavirus disease 2019 (Covid-19), tremendous efforts have been made by scientists, health professionals, business people, politicians, and laypeople around the world. Covid-19 vaccines are one of the most crucial innovations that help fight against the virus. This paper attempts to revisit the Covid-19 vaccines production process by employing the serendipity-mindsponge-3D creativity management theory. Vaccine production can be considered an information process and classified into three main stages. The first stage involved the processes of absorbing information (e.g., digital data and open science) and rejecting unhelpful information (e.g., misinformation and fake news) for effectively acquiring useful insights. Useful insights were later employed by experts, enterprises, governments, and international organizations through interdisciplinary coordinated efforts for developing vaccines within a short period. Finally, the appearance of multiple types of vaccines enabled more strategic options for vaccine distribution and administration. Findings from this vaccine creativity management process could be used as critical lessons for further improvements of vaccination programs

    20-Hydroxyecdysone from Dacrycarpus imbricatus bark inhibits the proliferation of acute myeloid leukemia cells

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    Abstract Objective To investigate the anti-proliferative effects of 20-hydroxyecdysone isolated from the bark of Dacrycarpus imbricatus (Blume) de Laub. Methods Column chromatography was used for isolation of compounds from plant material. The structure of the isolated compound was identified by mass spectrometry and nuclear magnetic resonance techniques, including HSQC, HMBC, NOE-difference experiments. The isolated compound was tested for its anti-proliferative activity in acute myeloid leukemia (AML) and OCI-AML cells. Results Compound 1 was isolated from the ethyl acetate fraction of Dacrycarpus imbricatus barks by column chromatography. Its chemical structure was identified as 20-hydroxyecdysone (20HE), a cholestane-type ecdysteroid, by a combination of mass spectrometry and nuclear magnetic resonance spectrometric analyses. Our goal was to test the anti-proliferative activity of 20HE using the OCI-AML cell line. 20HE significantly decreased OCI cell number at a concentration of 1 mg/mL, whereas lower concentrations were ineffective. Moreover, this decrease was due to partial blockage of the G 1 /S phase of the cell cycle, with a reduction of cells in the G 2 M phase, not due to increased apoptosis. Conclusions This indicates that 20HE significantly decreases the number of cells in the G 1 /S phase of the cell cycle in human AML cells. This is the first time that the anti-proliferative activity of 20HE against a human tumor cell line has been reported

    CHEMICAL CONSTITUENTS OF HEDYOTIS PINIFOLIA WALL. COLLECTED IN THUA THIEN HUE

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    This study reports the chemical constituents from the whole plants Hedyotis pinifolia Wall. Ex G. Don (now accepted as Oldenlandia  pinifolia (Wall. Ex G. Don) Kuntze) collected  in Thua Thien Hue province. Thirteen compounds were isolated by chromatography method. Their structures were elucidated using MS and NMR analysis and compared with reported data. They contain three anthraquinones, a carotenoid, two triterpenes, four iridoid glucosides and three flavonoid glycosides. Four of them were found for the first time in this genus
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