With the development of office forms, the space form of super high-rise office buildings changed from the unitary efficient office space to a complex space that integrated office, communication, and ...experience, which also diversified the design of typical floors in the office zone. However, from the perspective of fire prevention, the placement of shared space changed the form of the plane in typical floors in the office zone, affecting the smoke spreading of fire and paths of personnel evacuation. Hence, the subject on the planar relationship among high-rise office buildings based on fire prevention analysis, which optimizes space design, is worthy of discussion. After collecting many cases of super high-rise office buildings in China, this study categorized them into six typical planes and adopted the software PyroSim for comparative simulation of the smoke spreading of fire. By comparing the visibility of different zones in fires, this study analyzed the effects of the area of the office zone, the location of the atrium, and the form of the plane on the fire visibility on the typical floor and put forth the key factors that influence fire visibility, thus optimizing the plane design of the typical floor of super high-rise buildings. The findings show that in the six fire scenes, the area of the office zone is between 1136m2 and 1736m2. The peak of duration for visibility decline at 1.5 m appeared in Scene 3. Its office zone is 1536m2, and the duration of visibility decline is greater than 1000 s. In other fire scenes, the duration of visibility decline is less than 300 s. By comparing the plane arrangement features of the fire scenes, the paper concludes that in a given fire scene, establishing an atrium in the office zone, expanding the length of the adjacent edge between the atrium and the office zone, and building an evacuation corridor between the atrium and the core tube can greatly extend the effective evacuation time. This can serve as reference for the plane design of super high-rise office buildings.
Water Droplet‐Based Nanogenerators Hasan, Md Al Mahadi; Zhang, Tongtong; Wu, Heting ...
Advanced energy materials,
10/2022, Letnik:
12, Številka:
37
Journal Article
Recenzirano
Water is one of the most sustainable resources in the world, offering an abundance of hydro energy. Getting a large amount of electricity through conventional water energy harvesting is expensive, ...with complex mechanisms and bulky installation systems. In the case of the small amount of energy for some portable electronic devices and sensor systems, water droplet harvesting as a sustainable energy resource has become a forward‐looking step to meet the future demand for green energy. The ultimate demand for green energy in the future requires all the possible sustainable energy sources surrounding human society. The emerging potential of water droplet‐driven energy‐harvesting nanogenerators can meet a significant portion of the green energy demand. In this review, the recent developments in droplets‐driven nanogenerators for effective energy scavenging is summarized. It also includes an extensive discussion about the device structures from the material selection and output performance aspects. This review also gives a brief discussion on the applications of droplet‐based nanogenerators and outlines the future possibilities via the current improvement in designs and fabrication strategies that have been introduced by the field.
Droplets‐based nanogenerators are droplet harvesting devices for energy scavenging effectively through contact electrification, piezoelectrification, and other processes. The outputs from droplet‐based nanogenerators can be used in many sensor networks and portable electronics. With further development, droplet harvesting can become a sustainable energy resource with the proper utilization of droplet‐based nanogenerators.
Ketamine is a non-competitive channel blocker of N-methyl-D-aspartate (NMDA) receptors
. A single sub-anaesthetic dose of ketamine produces rapid (within hours) and long-lasting antidepressant ...effects in patients who are resistant to other antidepressants
. Ketamine is a racemic mixture of S- and R-ketamine enantiomers, with S-ketamine isomer being the more active antidepressant
. Here we describe the cryo-electron microscope structures of human GluN1-GluN2A and GluN1-GluN2B NMDA receptors in complex with S-ketamine, glycine and glutamate. Both electron density maps uncovered the binding pocket for S-ketamine in the central vestibule between the channel gate and selectivity filter. Molecular dynamics simulation showed that S-ketamine moves between two distinct locations within the binding pocket. Two amino acids-leucine 642 on GluN2A (homologous to leucine 643 on GluN2B) and asparagine 616 on GluN1-were identified as key residues that form hydrophobic and hydrogen-bond interactions with ketamine, and mutations at these residues reduced the potency of ketamine in blocking NMDA receptor channel activity. These findings show structurally how ketamine binds to and acts on human NMDA receptors, and pave the way for the future development of ketamine-based antidepressants.
Zearalenone (ZEA) is an oestrogen-like mycotoxin produced by Fusarium fungi, which has a considerable impact on human and animal health and results in substantial economic losses worldwide. This ...study aimed to demonstrate the reproductive injury induced by ZEA in rodents. We conducted a rigorous meta-analysis of the related literature via PubMed, Embase, and Web of Science. The scope of the study includes the following: development of reproductive organs, serum testosterone, oestradiol, and luteinizing hormone (LH) levels; parameters of Leydig cells; and parameters of semen. In total, 19 articles were reviewed. Compared with the control group, the increased relative epididymis weight, increased serum oestradiol level, and decreased LH levels in the prenatally exposed group were observed. In pubertal and adult rodents, the relative testicular weight, serum oestradiol level, Leydig cell number, and percentage of ST (+) Leydig cells decreased under ZEA exposure. In rodents at all ages, decreased serum testosterone level, sperm concentration, sperm motility rate, and increased serum deformity rate were observed in exposed groups compared with control groups. Although subgroup analysis failed to identify a clear dose–response relationship between ZEA exposure and reproductive system damage in male rodents, we still managed to confirm that zearalenone could decrease the serum testosterone level at the dosage of 50 mg/kg*day, 1.4 mg/kg*day, and 84 mg/kg*day, of prenatal, pubertal, and mature rodents respectively; pubertal zearalenone exposure impairs the quality and quantity of sperms of rodents at the dosage of 1.4 mg/kg*day and mature zearalenone exposure has the same effect at the dosage of 84 mg/kg*day. In conclusion, we found that ZEA exposure can cause considerable damage to the reproductive system of rodents of all ages. While the exact underlying mechanism of ZEA-induced toxicity in the reproductive system remains largely unknown, the theories of oestrogen-like effects and oxidative stress damage are promising.
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•Zearalenone decreases the serum testosterone level at the dosage of 50 mg/kg*day, in prenatal rodents.•Pubertal zearalenone exposure impairs the quality and quantity of sperms in rodents at the dosage of 1.4 mg/kg*day.•Mature zearalenone exposure impairs the quality and quantity of sperms in rodents at the dosage of 84 mg/kg*day.
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•A phosphorus/silica synergistic multifunctional epoxy additive (ETP) was synthesized.•ETP shows excellent flame-retardant and smoke-suppressant performances.•The toughness of the ...cured product increased by 114 % with the addition of 6 wt% ETP.•6 wt% ETP improves the dielectric and hydrophobic properties by more than 40 %.
Developing epoxy resins with superior toughness, flame retardant and hydrophobic as well as dielectric properties remains a huge challenge. Herein, an epoxy additive (ETP) was prepared by grafting phosphorus-containing molecules into the skeleton of silicone resin through silicon hydrogen addition reaction. Through such a design, the obtained ETP imparted Bisphenol A epoxy resin (DGEBA) with excellent flexibility, fire safety, hydrophobicity and dielectrical property. When only 6 wt% of ETP was introduced into the DGEBA system, the resulting product (ETP-6) passed the V-0 level in the UL-94 test with a high limiting oxygen index of 29.8 %, which could be ascribed to the presence of phosphorus and silicon element. Meanwhile, compared with neat DGEBA, the peak heat releases and smoke emissions of ETP-6 were reduced by 32.7 % and 37.8 % during the combustion. Additionally, ETP also imparted the cured product with excellent hydrophobic and dielectric properties, as well as superior toughness (114.5 % increase in impact strength) due to its “rigid and flexible” silicone skeleton and good dispersion. This work opens up a new strategy for developing high-performance and multifunctional epoxy resin additives with potential versatile applications.
As species extinction accelerates globally and biodiversity declines dramatically, identifying keystone species becomes an effective way to conserve biodiversity. In traditional approaches, it is ...considered that the extinction of species with high centrality poses the greatest threat to secondary extinction. However, the indirect effect, which is equally important as the local and direct effects, is not included. Here, we propose an optimized disintegration strategy model for quantitative food webs and introduced tabu search, a metaheuristic optimization algorithm, to identify keystone species. Topological simulations are used to record secondary extinctions during species removal and secondary extinction areas, as well as to evaluate food web robustness. The effectiveness of the proposed strategy is also validated by comparing it with traditional methods. Results of our experiments demonstrate that our strategy can optimize the effect of food web disintegration and identify the species whose extinction is most destructive to the food web through global search. The algorithm provides an innovative and efficient way for further development of keystone species identification in the ecosystem.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
An electrochemiluminescence-electrochemistry (ECL-EC) dual-mode sensing platform based on a vertically-ordered mesoporous silica films (VMSF) modified electrode was designed here for the sensitive ...and selective determination of cancer antigen 15-3 (CA 15-3), a specific biomarker of breast cancer. VMSF was assembled through a rapid electrochemically assisted self-assembly (EASA) method and plays a crucial role in signal amplification via a strong electrostatic interaction with the positively charged bifunctional probe Ru(bpy
. To construct the biorecognition interface, epoxy functional silane was linked to the surface of VMSF for further covalent immobilization of the antibody. As a benefit from the specific combination of antigen and antibody, a non-conductive immunocomplex layer was formed in the presence of CA 15-3, leading to the hinderance of the mass and electron transfer of the probes. Based on this strategy, the dual-mode determination of CA 15-3 ranging from 0.1 mU/mL to 100 mU/mL with a LOD of 9 μU/mL for ECL mode, and 10 mU/mL to 200 U/mL with a LOD of 5.4 mU/mL for EC mode, was achieved. The proposed immunosensor was successfully employed for the detection of CA 15-3 in human serum without tedious pretreatment.
Immunotherapy is a vital treatment for patients with cutaneous melanoma (CM), but effective predictors to guide clinical immunotherapy are lacking. Cuproptosis is a newly discovered mode of cell ...death related to tumorigenesis. Exploring the relationship between the mode of cuproptosis and the effect of immunotherapy on CM could better guide clinical management. We clustered all patients with CM in the Cancer Genome Atlas (TCGA) database based on cuproptosis-related genes (CRGs). Prognosis, immunotherapeutic effect, tumor microenvironment score, expression of CD274, CTLA4, and PDCD1, and abundance of CD8 + T infiltration in group A were higher than in group B. Using a combination of LASSO and COX regression analysis, we identified 10 molecules significant to prognosis from differentially expressed genes between the two groups and constructed a cuproptosis-related scoring system (CRSS). Compared with the American Joint Committee on Cancer (AJCC) staging system, CRSS more accurately stratified CM patient risk and guided immunotherapy. CRSS successfully stratified risk and predicted the effect of immunotherapy in 869 patients with eight CM immunotherapy datasets and multiple other tumor immunotherapy cohorts. The nomogram model, which combined AJCC stage and CRSS, greatly improved the ability and accuracy of prognosis prediction. In general, our cuproptosis-related scoring system and nomogram model accurately stratified risk in CM patients and effectively predicted prognosis and the effect of immunotherapy in CM patients.
Polystyrene microplastics (PS-MPs) are emerging pollutants that are absorbed by organisms. Due to their small volume and strong biological permeability, they affect the biological functions of cells. ...In recent years, several studies have detected PS-MPs in air samples, which may damage the human respiratory system following inhalation. The Masson trichrome staining, immunofluorescence, and western blotting assays were conducted to analyze the effects of PS-MPs on pulmonary fibrosis. Alveolar epithelial injuries were assessed through confocal microscopy, and the levels of SOD and GSH were used to evaluate oxidative stress. Our analyzes demonstrated that inhalation of the PS-MPs induces pulmonary fibrosis in a dose-dependent manner in mice. In high dose group (6.25 mg/kg), the PS-MPs significantly increased the expression of α-SMA, Vimentin and Col1a (p < 0.05). Immunofluorescence assays showed decreased levels of SP-C and increased levels of KL-6 in the PS-MPs group. The suppression of SOD (1.46 times) and GSH-Px (2.27 times) indicated that inhalation of microplastics triggered intensive oxidative stress in lungs. Moreover, there was activation of the Wnt/β-catenin signaling pathway in the PS-MPs group. In addition, the data showed that antioxidant melatonin (50 mg/kg) alleviated the PS-MPs-induced pulmonary fibrosis. Taken together, our analysis demonstrated that inhalation of polystyrene microplastics induces pulmonary fibrosis via activation of oxidative stress and Wnt/β-catenin signaling pathway in mice.
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•Inhalation of polystyrene microplastics induced pulmonary fibrosis in mice.•Exposure to polystyrene microplastics induced oxidative stress and alveolar epithelial injuries.•Polystyrene microplastics exposure activated Wnt/β-catenin signaling pathway.•Melatonin can alleviate the polystyrene microplastics related pulmonary fibrosis.
Layered Ti-Al metal composite (LMC) was designed and fabricated by hot-rolling and annealing of pure Ti and Al sheets. The as-prepared composite exhibits high tensile ductility, being superior to any ...individual Ti or Al sheets. The stress/strain evolution and fracture behavior of the LMC were analyzed by in-situ observations during the tensile deformation. Three deformation stages of LMC were clearly observed by neutron diffraction: elastic stage, elastic-plastic stage and plastic stage. It is found that stress partitioning at the elastic-plastic deformation stage improves the strain balance of LMC, but leads to an internal stress accumulated at the interface. Additionally, a strain-transfer from Ti to adjacent Al layers relieves the strain localization of Ti layers in LMC, which improves the ductility of Ti. Both stress partitioning and strain localization of Ti layers facilitate the nucleation of cracks at a low macro strain. However, the crack propagation is constrained by layered structure. In terms of the Al layers, the constrained micro-cracks relieve the stress concentration in Al layer and improve the ductility of Al layers, so that cracking indirectly affects the plastic deformation behavior of LMC, then improving its entire ductility. This work provides a new structural strategy towards simultaneously improving strength and ductility to develop high performance LMC by structural design.
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