Many offshore projects, such as offshore oil and gas exploration and offshore wind farm development, have required controlling the position of elevating the hull in a stable and balanced manner in ...recent years. The Jack-up Rig (JuR) jacking control systems are a revolutionary innovation that is already being employed in offshore drilling and other maritime structures. The system is utilized automatically to control and stabilize the position of the JuR during sea state disturbances to keep platforms from being displaced. As a result, developing an improved control theory for the Jacking system (JS) of a JuR is very important. In this paper, first, we investigate how to adapt to the effects of external forces and hydrodynamic amplification using a particle swarm optimization strategy based on a fuzzy controller. Then, using the fuzzy controller as the foundation, we proposed the PSO - Self Adaptive Fuzzy Controller (PSO-SAFC) guaranteed by Lyapunov criteria and compares it with other fuzzy-based algorithms to show the benefit of adaptively and stability of the system. To verify the proposed algorithm, embedded STM32F746VG central processor used to build the algorithm and run Simulink models on Matlab, the collected data on the positions of the legs and the tilt compared it to the setting command values to move the Rig body and provided control signals to the Drive system. Eventually, the advantages of the proposed approach are demonstrated by the simulation and experiment outcomes.
An electro-Fenton system, which consists of a Pt gauze anode and a commercial carbon felt cathode, is commonly employed to generate in situ hydrogen peroxide, hydroxyl radical and regenerate ferrous ...catalyst for glyphosate degradation (a widely used herbicide in Vietnam) in aqueous solution. The absorbance measurements used to determine the glyphosate concentration during the electrolysis proved that glyphosate was degraded by pseudo-first-order kinetic. The influence of pH, current density, catalyst concentration and initial content of the glyphosate on mineralisation efficiency were studied by monitoring the total organic carbon (TOC) and hydrogen peroxide concentration during electrolysis. The results show that the maximal removal percentage of glyphosate was 91.91% with applied current density of 10 mA cm
−2
, pH 3, 0.1 mM Fe
2+
, 0.05 M Na
2
SO
4
, and 0.1 mM glyphosate in 40 min. The degrading rate constant of glyphosate degradation was calculated to be k
app
= 0.063 min
−1
. In this 91.91% removal, 81.65% of glyphosate was mineralised and the remainder consists of intermediates produced during the electro-Fenton process.
Silicon nanowires (SiNWs) were prepared by metal-assist chemical etching (MACE) from different doping types and resistivity of Si wafers, orientation. The coexistence of Si nanocrystals (SiNCs) and ...SiNWs was revealed in both types of the semiconductor. From the p-type samples, heavily doped with boron (B), intense red-light emission was observed. High-resolution transmission electron microscopy (HR-TEM) images of this sample type shown numerous SiNCs in the porous surface of the SiNWs walls. These SiNCs were proposed to be responsible for the characterized optical properties of the material. The microscopic links between the photoluminescence behavior, the dopants, and the formation of SiNCs were presented and discussed.
•Vertically aligned p-type and n-type silicon nanowires were fabricated by metal-assist chemical etching.•The coexistence of Si nanocrystals and nanowires in both types.•The most intense photoluminescent intensity found in heavily B-doped samples.•Formation of the Si nanocrystals and their microscopic link with dopants and optical characterization.
Adipokines are involved in the pathogenesis of metabolic disorders including obesity and type 2 diabetes mellitus (T2DM). This study investigates the levels of leptin, resistin, visfatin, secreted ...frizzled-related protein 5 (SFRP5), monocyte chemoattractant protein-1 (MCP-1) and retinol-binding protein 4 (RBP4) and their correlations with clinical parameters of overweight and T2DM.
We recruited overweight 50 patients with T2DM, 88 non-overweight patients with T2DM, 29 overweight and 100 non-overweight individuals devoid of T2DM for this study. The levels of studied adipokines were measured by enzyme-linked immunosorbent assay and correlated with clinical parameters.
The levels of MCP-1 and SFRP5 were decreased while visfatin and RBP4 levels were increased in patients with T2DM compared to those in the control individuals (
< 0.01). Among patients with T2DM, leptin and resistin levels were higher while RBP4 levels were lower in patients with overweight T2DM compared to those in patients with non-overweight T2DM (
< 0.0001, 0.019 and 0.05, respectively). Leptin and MCP-1 levels were correlated with HOMA-IR, QUICKI and HOMA-β. Leptin/MCP-1 ratio was correlated with insulin levels, HOMA-IR and HOMA-β indexes. Resistin/RBP4, visfatin/MCP-1 and MCP-1/RBP4 ratios were strongly correlated with the levels of fasting glucose, HbA1c and HOMA-β. In addition, ROC curve analyses indicated a diagnostic potential of resistin/RBP4 and MCP-1/RBP4 indexes for T2DM (AUC = 0.81 and 0.83, respectively) and β-cell function (AUC = 0.76 and 0.74, respectively).
Adipokines (leptin, resistin, visfatin, SFRP5, MCP-1, and RBP4) are associated with overweight and T2DM and may serve as a potential prognostic marker and therapeutic intervention for overweight-related T2DM.
BACKGROUND Esophageal invasion in hypopharyngeal cancer is an uncommon lesion and has a poor prognosis. Total pharyngo-laryngo-esophagectomy is the most effective treatment option. Reconstruction of ...the gastrointestinal tract in the same period of surgery is required. There are many different options, such as pedicle flap, gastric pull-up, pedicled transverse colon flaps, and free flap. In cases where only cervical esophagectomy is required, with benefits for patients, jejunal free flap is the first choice to reconstruct the esophagus. However, the extensive surgical resection requires interdisciplinary collaboration among surgical specialities, which is not always available. CASE REPORT A 52-year-old male patient came to us with a chief concern of dysphagia, which first appeared 3 months ago. Rigid fiberoptic and direct laryngoscopes indirectly observed the tumor at the posterior wall; it had passed the esophagus opening and infiltrated to the cervical esophagus, with the rightmost part spread into the right pyriform sinus. Histopathology studies of the tumor showed a squamous cell carcinoma. The patient underwent total pharyngo-laryngo-cervico-esophagectomy, reconstructed with a jejunal free flap, and adjuvant radiation therapy after surgery. At follow-up 1 year after surgery, the patient was significantly recovery with no signs of tumor recurrence, no difficulties of oral intake, and his speech was restored by electrolarynx. CONCLUSIONS We reported the case of a patient with hypopharyngeal cancer who underwent total pharyngo-laryngo-cervico-esophagectomy and esophagus reconstruction using a jejunal free flap, performed for the first time in Vietnam. As expected, with good oncological and functional results, the degree of invasiveness and sequelae of the surgery can be well tolerated.
In recent years, serosurveillance has gained momentum as a way of determining disease transmission and immunity in populations, particularly with respect to vaccine-preventable diseases. At the end ...of 2017, the Oxford University Clinical Research Unit and the National Institute of Hygiene and Epidemiology held a meeting in Vietnam with national policy makers, researchers, and international experts to discuss current seroepidemiologic projects in Vietnam and future needs and plans for nationwide serosurveillance. This report summarizes the meeting and the plans that were discussed to set up nationwide serosurveillance in Vietnam.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mangroves are highly productive ecosystems that exhibit a diverse range of habitats, including tidal creeks and flats, forest gaps and interior forest with varying understory light intensity, tidal ...dynamics, geomorphological settings, and overall biological production. Within mangrove ecosystems, invertebrates and fish feed on heterogeneous food sources, the occurrence of which is unevenly distributed across the system. This provides a basis for testing models of carbon transfer across mangrove ecosystems. We hypothesized that the carbon transfer and assimilation by fish and invertebrates will vary across the different mangrove habitats and that such variations can be predicted by their stable isotope compositions. We analysed δ13C and δ15N signatures of consumers and their potential organic carbon sources across a tropical mangrove ecosystem in Vietnam. The δ13C values of crabs and snails significantly decreased from the tidal flat to interior forest, indicating that variations in carbon transfer and assimilation occurred at small scales <30 m. Reduced variation in δ13C of suspension‐feeding bivalves suggested that tidal water was a vector for large‐scale transport of carbon across the mangrove ecosystem. An analysis of co‐variance using habitat as a fixed factor and feeding habit and movement capacity of consumers as co‐variates indicated that habitat and feeding types were major features that affected the δ13C values of invertebrates and fish. The findings demonstrate that carbon transfer and assimilation across mangrove ecosystems occur as a diverse combination of small (<30 m) and large (>30 m) scale processes.
Energy consumption was skyrocketing along with fast economic development as well as continuous global population growth. Furthermore, environmental concerns about greenhouse gas emissions were also ...increasing, which indicated that these issues could be resolved by the development and utilization of renewable and clean energy. Among many renewable kinds of energy, hydrogen was considered the cleanest generating water because it was the only combustion product, allowing for truly zero pollutant emissions. As a result, developing efficient hydrogen generation technologies that utilized biomass feedstock, and ensured clean energy produced with low-carbon emissions was critical in helping fight against global warming as well as obtain waste recovery. In this paper, recent investigation advances in the generation of hydrogen from biomass pyrolysis and gasification were comprehensively reviewed in this regard. Also, the most recent studies on biomass pyrolysis and gasification in the use of biomass waste to produce hydrogen, with an emphasis on technical problems, efficiency, and mechanism were summarized. Following that, challenges and opportunities were presented for enhancing the efficiencies of the process and the quality of the products, which was significant to obtain sustainable and green development. Importantly, even though several advances and innovations in generating hydrogen from biomass were made using existing technologies, more scientific advances were needed to make it economically competitive as well as environmentally friendly for industrial production on large scale. Overall, the entire article gives a consolidated overview of the optimal condition suggested for superior H2 yield, and %volume from various biomass.
•Hydrogen (H2) is known as the green and clean fuel for decarbonization strategies.•Biomass wastes are considered potential renewable sources for H2 production.•Recent advances in pyrolysis and gasification for H2 production are scrutinized.•Opportunities and challenges of H2 production from biomass wastes are discussed.
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