112 research outputs found
Experimental study of the salt solution erosing influence on strength of concrete with recycled coarse aggregate
There are carried out the experimental study of the loss of the recycled concrete’s strength depending on the recycled coarse aggregate substitution ratio, quantity of the fly ash and age of the concrete through investigation of the concrete’s compressive strength. It is shown that compared with natural gravel, the recycled coarse aggregates accumulate damages at crushing process and have a lot of micro cracks. In addition, the surface of gravel is wrapped in porous adhesive mortar which provides corrosion resistance of concrete deterioration. With the amount of recycled coarse aggregate increasing, the compressive strength of recycled concrete decreases. The addition of fly ash, which creates a compaction effect, helps improve the erosion resistance of recycled concrete. It is shown that positive effect of aging of recycled concrete is significantly higher than negative effect of salt solution erosion, so with time the strength of recycled concrete is increased
Basic Fibroblast Growth Factor Inhibits Osteogenic Differentiation of SHED through ERK Signaling
Objective Stem cells from human exfoliated deciduous teeth (SHED) are a unique postnatal stem cell population capable of regenerating mineralized tissue and treating immune disorders. However, the mechanism that controls SHED differentiation is not fully understood. Here, we showed that basic fibroblast growth factor (bFGF) treatment attenuated SHED-mediated mineralized tissue regeneration through activation of the extracellular signal-regulated kinase (ERK) 1/2 pathway. Material and Method The level of mineralized nodule formation was assessed by alizarin red staining. Expression levels of osteogenic genes, OCN and Runx2, were examined by RT-PCR. Subcutaneous implantation approach was used to assess in vivo bone formation. Downstream signaling pathways of bFGF were examined by Western blotting. Result Activation of ERK1/2 signaling by bFGF treatment inhibited WNT/β-catenin pathway, leading to osteogenic deficiency of SHED. ERK1/2 inhibitor treatment rescued bFGF-induced osteogenic differentiation deficiency. Conclusion These data suggest that bFGF inhibits osteogenic differentiation of SHED via ERK1/2 pathway. Blockade ERK1/2 signaling by small molecular inhibitor-treatment improves bone formation of SHED after bFGF treatment
Dissipation Theory-Based Ecological Protection and Restoration Scheme Construction for Reclamation Projects and Adjacent Marine Ecosystems.
According to the 2017 results of the Special Inspector of Sea Reclamation, a substantial number of idle reclamation zones existed in 11 provinces (cities) along the coast of China. To improve the protection level of coastal wetlands and strictly control reclamation activities, it is necessary to carry out ecological restoration of reclamation projects and adjacent marine ecosystems. The characteristics of Guanghai Bay and its reclamation project are typical in China’s coastal areas, making it an optimal representative site for this study. The dissipative structure and entropy theory was used to analyze ecological problems and environmental threats. The analytic hierarchy process was applied to determine the order of the negative entropy flow importance. The entropy increase and decrease mechanism was used to determine an ecological protection and restoration scheme for the reclamation, including the reclamation of wetland resource restoration, shoreline landscape restoration, environmental pollution control, and marine biological resource restoration. Finally, based on system logic, a typical ecological restoration system was constructed east of Guanghai Bay, with the mangrove wetland area as the model in the north and the artificial sandbeach recreation area as the focus in the south
Advancements and challenges in pharmacokinetic and pharmacodynamic research on the traditional Chinese medicine saponins: a comprehensive review
Recent research on traditional Chinese medicine (TCM) saponin pharmacokinetics has revealed transformative breakthroughs and challenges. The multicomponent nature of TCM makes it difficult to select representative indicators for pharmacokinetic studies. The clinical application of saponins is limited by their low bioavailability and short half-life, resulting in fluctuating plasma concentrations. Future directions should focus on novel saponin compounds utilizing colon-specific delivery and osmotic pump systems to enhance oral bioavailability. Optimizing drug combinations, such as ginsenosides with aspirin, shows therapeutic potential. Rigorous clinical validation is essential for practical applications. This review emphasizes a transformative era in saponin research, highlighting the need for clinical validation. TCM saponin pharmacokinetics, guided by traditional principles, are in development, utilizing multidisciplinary approaches for a comprehensive understanding. This research provides a theoretical basis for new clinical drugs and supports rational clinical medication
Climate change : strategies for mitigation and adaptation
The sustainability of life on Earth is under increasing threat due to humaninduced climate change. This perilous change in the Earth's climate is caused by increases in carbon dioxide and other greenhouse gases in the atmosphere, primarily due to emissions associated with burning fossil fuels. Over the next two to three decades, the effects of climate change, such as heatwaves, wildfires, droughts, storms, and floods, are expected to worsen, posing greater risks to human health and global stability. These trends call for the implementation of mitigation and adaptation strategies. Pollution and environmental degradation exacerbate existing problems and make people and nature more susceptible to the effects of climate change. In this review, we examine the current state of global climate change from different perspectives. We summarize evidence of climate change in Earth’s spheres, discuss emission pathways and drivers of climate change, and analyze the impact of climate change on environmental and human health. We also explore strategies for climate change mitigation and adaptation and highlight key challenges for reversing and adapting to global climate change
Analysis on the situation of subjective well-being and its influencing factors in patients with ankylosing spondylitis
BACKGROUND: To examine the subjective well-being (SWB) in patients with ankylosing spondylitis (AS) compared with the healthy controls, and to explore the associations between SWB and demographic characteristics, disease-specific variables in AS patients. METHODS: SWB was assessed with General Well-Being Schedule (GWBS) in 200 AS patients and 210 healthy controls. Comparisons among subgroups were performed to investigate how certain aspects operate as favorable or adverse factors in influencing SWB in the patients with AS. RESULTS: Both men and women with AS reported significantly impaired SWB on all scales of the GWBS except for the Control (O) scale. The results revealed that better sleep, lower disease activity and more family care predicted higher SWB. In AS patients, positive attitude towards therapy prospect was significantly associated with higher SWB. Therapy prospect refers to the hope of patients about the disease treatment. CONCLUSIONS: Compared with general population, SWB might be affected by the onset of AS. There are significant associations between SWB and sleep quality, BASDAI, APGAR, therapy prospect
Cooling vest incorporated with phase change materials (PCMs): how much benefit is there?
The aim of this study was to investigate torso cooling benefit of various PCM vests in a simulated warm environment (Ta= 34 °C, RH=56 %, Va=0.4 m/s). A pre-wetted cotton torso fabric skin was used to simulate sweating on a thermal manikin (Tmanikin=34 °C). Six conditions were tested: nude fabric skin (Fabric Skin), Vest A without (VA) and with frozen gels with a melting temperature (Tm) of 0 °C (VA+Gel), Vest B without (VB) and with PCMs of Tm=21 °C (VB+PCM21) and Vest B with PCMs of Tm=24 °C (VB+PCM24). Cooling benefits for the three vests were: 10 W/m2 (VA+Gel), -49 W/m2 (VB+PCM21) and -52 W/m2 (VB+PCM24). The restricted evaporation rates were: 97 g/h (VA+Gel), 80 g/h (VB+PCM21), and 75 g/h (VB+PCM24). Torso fabric skin temperature was reduced by 1.6 °C (VA+Gel), 1.2 °C (VB+PCM21) and 0.2 °C (VB+PCM24). The results revealed that all the cooling vests presented negative benefits in a simulated work activity and environmental condition. The observed positive benefit could be only found on reducing local torso skin temperature
Effects of Two Cooling Garments on Post-exercise Thermal Comfort of Female Subjects in the Heat
The purpose of the study was to investigate and compare the effect of two cooling garments with phase change material (PCM) and ventilation on thermal comfort. Eight female university students (age 24±1 years; height 162±4 cm; body weight 54±4 kg) exercised on a treadmill in an environment of 32 oC with 50 % relative humidity. Tests in three conditions were carried out after moderate exercise with t-shirt and shorts: cooling with a PCM vest (PCM); cooling with a ventilation jacket (VEN) and without cooling clothing (natural cooling, a control condition, CON). Results showed that no significant differences were observed in the mean skin temperature and heart rate among the two cooling garment conditions and the control condition (p>0.05). The local torso skin temperature was observed with significant difference among the three conditions (p<0.05) and it was mostly reduced by 0.7 oC and 0.9 oC, respectively in PCM and VEN. Significant differences were observed in the clothing torso micro-climate temperature and humidity among the three testing scenarios (p<0.05). The clothing micro-climate temperature was dropped by 2 oC in PCM and 0.8 oC in VEN. The clothing micro-climate humidity in PCM was 40 % higher than that in VEN after 30 minutes cooling. The perceived thermal sensation was the lowest in PCM whereas the perceived skin wettedness sensation was the lowest in VEN
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