480 research outputs found
Small-Scale Energy Harvesting from Environment by Triboelectric Nanogenerators
The increasing needs to power trillions of sensors and devices for the Internet of Things require effective technology to harvest small-scale energy from renewable natural resources. As a new energy technology, triboelectric nanogenerators (TENGs) can harvest ambient mechanical energy and convert it into electricity for powering small electronic devices continuously. In this chapter, the fundamental working mechanism and fundamental modes of a TENG will be presented. It can harvest all kinds of mechanical energy, especially at low frequencies, such as human motion, walking, vibration, mechanical triggering, rotating tire, wind, moving automobile, flowing water, rain drops, ocean waves, and so on. Such variety of energy harvesting methods promises TENG as a new approach for small-scale energy harvesting
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Simulation of Particle Mixing and Separation in Multi-Component Fluidized Bed Using Eulerian-Eulerian Method: A Review
In practical engineering applications, the mixing and separation behavior of multi-component particles is importance to the fluidized bed operation. The development of many practical processes is inseparable from the knowledge of particle mixing and separation, such as material processing of ash-soluble coal gasification, multi-phase flow in boilers, and petrochemical catalytic processes. In recent years, due to the obvious advantages of the Eulerian–Eulerian model, many researchers at home and abroad have used it to study the mixing and separation behavior of particles. The paper reviews the use of Eulerian–Eulerian model to study the mixing and separation of multi-component particles in fluidized beds. The Eulerian–Eulerian model describes the gas-phase and each of the individual particles as continuums. The mechanism of particle mixing and separation, the influence of different factors on the particle mixing and separation including differences in particle size and density, the differences in apparent air velocity, the differences in model factors are discussed. Finally, an outlook for the use of Eulerian–Eulerian model to study the mixing and separation behavior of three component particles and related research on the drag model between particles
Anti-inflammation effects of hydrogen saline in LPS activated macrophages and carrageenan induced paw oedema
Past studies and potential measures for rehabilitation of the shallow lake (Lake Ludas)
Lake Ludaš has been under a strong anthropogenic influence for a very long time, so the history of fruitful scientific investigation was very often connected with the evaluation of a human impact and potential rehabilitation measures. Unfortunately, attempts to improve the lake's natural status remain more in the field of theoretical models than concrete practical solutions. Aiming to better understand the potential of different rehabilitation measures for Lake Ludaš, we combined our ecological analyses (unpublished results) and the literature survey. The continuous massive cyanobacterial bloom and the formation of a thick sediment layer rich in different organic and inorganic pollutants represent two major challenges in the lake's rehabilitation. The unknown ecological role of invasive species that have already colonised Lake Ludaš will make the attempts to improve conditions in the lake even more challenging. The reduction of nutrient load, changes in the intensity and directions of water circulation, as well as top sediment layer removal in the lake, are measures under consideration for several decades. But their combination, order of implementation and possibilities of successful execution are still under debate. However, there is no doubt that the restoration of a natural hydrological regime should be a key step in the rehabilitation of Lake Ludaš
Genetic characterization of \u3cem\u3eToxoplasma gondii\u3c/em\u3e from pigs from different localities in China by PCR-RFLP
Background
Toxoplasma gondii is a widely prevalent protozoan parasite that causes serious toxoplasmosis in humans and animals. The present study aimed to determine the genetic diversity of T. gondii isolates from pigs in Jiangxi, Sichuan, Guangdong Provinces and Chongqing Municipality in China using multilocous polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. Methods
A total of 38 DNA samples were extracted from hilar lymph nodes of pigs with suspected toxoplasmosis, and were detected for the presence of T. gondii by semi-nested PCR of B1 gene. The positive DNA samples were typed at 11 genetic markers, including 10 nuclear loci, namely, SAG1, 5′-SAG2 and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast locus Apico. Results
Twenty-five of the 38 DNA samples were T. gondii B1 gene positive. Complete genotyping data for all loci could be obtained for 17 of the 25 samples. Two genotypes were revealed (ToxoDB PCR-RFLP genotypes #9 and #3). Sixteen samples belong to genotype #9 which is the major lineage in mainland China and one sample belongs to genotype #3 which is Type II variant. Conclusions
To our knowledge, this is the first report of genetic typing of T. gondii isolates from pigs in Jiangxi, Sichuan Province and Chongqing Municipality, and the first report of ToxoDB #3 T. gondii from pigs in China. These results have implications for the prevention and control of foodborne toxoplasmosis in humans
Clinical characteristics associated with recurrent viral RNA positivity in patients within two weeks after recovering from the first SARS-CoV-2 infection
Many studies have shown that recovered coronavirus disease 2019 (COVID-19) patients frequently exhibit recurrent viral RNA positivity (RP) for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our study aimed to summarize the clinical characteristics of these patients and explore potential reasons for RP occurrence. We divided 439 participants into four groups based on the severity of illness prior to the COVID-19 recovery and age: mild-child group, moderate-child group, mild-adult group, and moderate-adult group. Laboratory data were collected and statistically analyzed using the SPSS software, version 24.0. Significant differences were observed in age, alanine aminotransferase (ALT), aspartate aminotransferase (AST), C-reactive protein (CRP), interleukin 6 (IL-6), and neutrophil to lymphocyte ratio (NLR) levels between the mild-adult group and the moderate-adult group (P < 0.05). Additionally, AST levels differed significantly between the mild-child group and the moderate-child group (P < 0.05). The proportion of RP patients within the four groups varied from 7.95% to 26.13% within a 2-week period. Logistic regression analysis revealed that younger age and moderate symptoms were risk factors for RP in children, while the presence of comorbidities (such as chronic heart, lung, liver, and kidney diseases), elevated IL-6 levels, and NLR were risk factors for RP in adults. We constructed two predictive models containing these relevant parameters, and the results of the receiver operating characteristic (ROC) curves indicated strong predictive utility. Our findings suggest that younger children with more severe symptoms, as well as adult patients with elevated levels of IL-6 and NLR and underlying diseases, are at higher risk of RP occurrence
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Oscillation-specific nodal alterations in early to middle stages Parkinsons disease.
Background: Different oscillations of brain networks could carry different dimensions of brain integration. We aimed to investigate oscillation-specific nodal alterations in patients with Parkinsons disease (PD) across early stage to middle stage by using graph theory-based analysis. Methods: Eighty-eight PD patients including 39 PD patients in the early stage (EPD) and 49 patients in the middle stage (MPD) and 36 controls were recruited in the present study. Graph theory-based network analyses from three oscillation frequencies (slow-5: 0.01-0.027 Hz; slow-4: 0.027-0.073 Hz; slow-3: 0.073-0.198 Hz) were analyzed. Nodal metrics (e.g. nodal degree centrality, betweenness centrality and nodal efficiency) were calculated. Results: Our results showed that (1) a divergent effect of oscillation frequencies on nodal metrics, especially on nodal degree centrality and nodal efficiency, that the anteroventral neocortex and subcortex had high nodal metrics within low oscillation frequencies while the posterolateral neocortex had high values within the relative high oscillation frequency was observed, which visually showed that network was perturbed in PD; (2) PD patients in early stage relatively preserved nodal properties while MPD patients showed widespread abnormalities, which was consistently detected within all three oscillation frequencies; (3) the involvement of basal ganglia could be specifically observed within slow-5 oscillation frequency in MPD patients; (4) logistic regression and receiver operating characteristic curve analyses demonstrated that some of those oscillation-specific nodal alterations had the ability to well discriminate PD patients from controls or MPD from EPD patients at the individual level; (5) occipital disruption within high frequency (slow-3) made a significant influence on motor impairment which was dominated by akinesia and rigidity. Conclusions: Coupling various oscillations could provide potentially useful information for large-scale network and progressive oscillation-specific nodal alterations were observed in PD patients across early to middle stages
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