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Various acoustic materials are developed to resolve noise pollution problem in many industries. Especially, materials with porous structure are broadly used to absorb sound energy in civil construction and transportation area. Polyurethane (PU) porous materials possess excellent damping properties, good toughness, and well-developed pore structures, which have a broad application prospect in sound absorption field. This work aims to summarize the recent progress of fabrication and structure for PU porous materials in sound absorption application. The sound absorption mechanisms of porous materials are introduced. Different kinds of structure for typical PU porous materials in sound absorption application are covered and highlighted, which include PU foam, modified PU porous materials, aerogel, templated PU, and special PU porous materials. Finally, the development direction and existing problems of PU material in sound absorption application are briefly prospected. It can be expected that porous PU with high sound absorption coefficient can be obtained by using some facile methods. The design and accurate regulation of porous structures or construction of multilayer sound absorption structure is favorably recommended to fulfill the high demand of industrial and commercial applications in the future work.
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Poliuretanos , Poliuretanos/química , Porosidade , SomRESUMO
Searches for the axion and axionlike particles may hold the key to unlocking some of the deepest puzzles about our Universe, such as dark matter and dark energy. Here, we use the recently demonstrated spin-based amplifier to constrain such hypothetical particles within the well-motivated "axion window" (10 µeV-1 meV) through searching for an exotic dipole-dipole interaction between polarized electron and neutron spins. The key ingredient is the use of hyperpolarized long-lived ^{129}Xe nuclear spins as an amplifier for the pseudomagnetic field generated by the exotic interaction. Using such a spin sensor, we obtain a direct upper bound on the product of coupling constants g_{p}^{e}g_{p}^{n}. The spin-based amplifier technique can be extended to searches for a wide variety of hypothetical particles beyond the standard model.
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Recently, research about droplet self-transportation on slippery surfaces has become a hotspot. However, to achieve on/off sliding control during the self-transportation process is still difficult. Herein, we report a magnetic slippery surface, and demonstrate on/off sliding control during the self-transportation of superparamagnetic droplets. The surface is prepared through integrating a substrate that has a gradient magnetic region with a layer of paraffin infused hydrophobic SiO2 nanoparticles. On the surface, a superparamagnetic droplet is pinned at room temperature (about 25 °C), while it can self-transport directionally as the temperature is increased to about 70 °C. When the temperature is cooled down again, the droplet would return to the pinned state, indicating that on/off sliding control during the self-transportation process can be achieved. Furthermore, based on the excellent controllability, controllable coalescence of two droplets from opposite direction is displayed, demonstrating its potential application in numerous areas.
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Temperatura Baixa , Dióxido de Silício , Transição de Fase , Nanopartículas Magnéticas de Óxido de Ferro , Fenômenos MagnéticosRESUMO
The relationship between the interfacial rheology of nanoparticle (NP) laden air-brine interfaces and NP adsorption and interparticle interactions is not well understood, particularly as a function of the surface chemistry and salinity. Herein, a nonionic ether diol on the surface of silica NPs provides steric stabilization in bulk brine and at the air-brine interface, whereas a second smaller underlying hydrophobic ligand raises the hydrophobicity to promote NP adsorption. The level of NPs adsorption at steady state is sufficient to produce an interface with a relatively strong elastic dilational modulus E' = dγ/d ln A. However, the interface is ductile with a relatively slow change in E' as the interfacial area is varied over a wide range during compression and expansion. In contrast, for silica NPs stabilized with only a single hydrophobic ligand, the interfaces are often more fragile and may fracture with small changes in area. The presence of concentrated divalent cations improves E' and ductility by screening electrostatic dipolar repulsion and strengthening the attractive forces between nanoparticles. The ability to tune the interfacial rheology with NP surface chemistry is of great interest for designing more stable gas/brine foams.
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The design of surface chemistries on nanoparticles (NPs) to stabilize gas/brine foams with concentrated electrolytes, especially with divalent ions, has been elusive. Herein, we tune the surface of 20 nm silica NPs by grafting a hydrophilic and a hydrophobic ligand to achieve two seemingly contradictory goals of colloidal stability in brine and high NP adsorption to yield a viscoelastic gas-brine interface. Highly stable nitrogen/water (N2/brine) foams are formed with CaCl2 concentrations up to 2% from 25 to 90 °C. The viscoelastic gas-brine interface retards drainage of the lamellae, and the high dilational elasticity arrests coarsening (Ostwald ripening) with no observable change in foam bubble size over 48 h. The ability to design NP-laden viscoelastic interfaces for highly stable foams, even with high divalent ion concentrations, is of fundamental mechanistic interest for a broad range of foam applications and in particular foams for CO2 sequestration and enhanced oil recovery.
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INTRODUCTION: Influenza has been linked to the crowding in emergency departments (ED) across the world. The impact of the Coronavirus Disease 2019 (COVID-19) pandemic on China EDs has been quite different from those during past influenza outbreaks. Our objective was to determine if COVID-19 changed ED visit disease severity during the pandemic. METHODS: This was a retrospective cross sectional study conducted in Nanjing, China. We captured ED visit data from 28 hospitals. We then compared visit numbers from October 2019 to February 2020 for a month-to-month analysis and every February from 2017 to 2020 for a year-to-year analysis. Inter-group chi-square test and time series trend tests were performed to compare visit numbers. The primary outcome was the proportion of severe disease visits in the EDs. RESULTS: Through February 29 th 2020, there were 93 laboratory-confirmed COVID-19 patients in Nanjing, of which 40 cases (43.01%) were first seen in the ED. The total number of ED visits in Nanjing in February 2020, were dramatically decreased (n = 99,949) in compared to January 2020 (n = 313,125) and February 2019 (n = 262,503). Except for poisoning, the severe diseases in EDs all decreased in absolute number, but increased in proportion both in year-to-year and month-to-month analyses. This increase in proportional ED disease severity was greater in higher-level referral hospitals when compared year by year. CONCLUSION: The COVID-19 outbreak has been associated with decreases in ED visits in Nanjing, China, but increases in the proportion of severe ED visits.
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COVID-19/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Índice de Gravidade de Doença , China/epidemiologia , Estado Terminal/epidemiologia , Estudos Transversais , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2RESUMO
BACKGROUND & AIMS: The Chinese herbal medicine, MaZiRenWan (MZRW), has been used for more than 2000 years to treat constipation, but it has not been tested in a randomized controlled trial. We performed a trial to evaluate the efficacy and safety of MZRW, compared with the stimulant laxative senna or placebo, for patients with functional constipation (FC). METHODS: We performed a double-blind, double-dummy, trial of 291 patients with FC based on Rome III criteria, seen at 8 clinics in Hong Kong from June 2013 through August 2015. Patients were observed for 2 weeks and then assigned randomly (1:1:1) to groups given MZRW (7.5 g, twice daily), senna (15 mg daily), or placebo for 8 weeks. Patients were then followed for 8 weeks and evaluated at baseline and weeks 4, 8 (end of treatment), and 16 (end of follow up). Participants recorded information on stool form and frequency, feeling of complete evacuation, and research medication taken. Data on individual bowel symptoms, global symptom improvement, and adverse events were collected. A complete response was defined as an increase ≥1 complete spontaneous bowel movement (CSBM)/week from baseline (the primary outcome). Secondary outcomes included response during the follow-up period, colonic transit, individual and global symptom assessments, quality of life measured with 36-item short form Chinese version, and adverse events. RESULTS: Although there was no statistically significant difference in proportions of patients with a complete response to MZRW (68%) vs. senna (57.7%) (P = .14) at week 8, there was a statistically significant difference vs. placebo (33.0%) (P < .005). At the 16-week timepoint (after the 8-week follow-up period), 47.4% of patients had a complete response to MZRW, 20.6% had a complete response to senna, and 17.5% had a complete response to placebo (P < .005 for MZRW vs. placebo). The group that received MZRW group also had significant increases in colonic transit and reduced severity of constipation, straining, incomplete evacuation, and global constipation symptoms compared with the groups that received placebo or senna in (P < .05 for all comparisons). CONCLUSIONS: In a randomized controlled trial of 291 patients with FC, we found MZRW to be well-tolerated and effective in increasing CSBM/week. MZRW did not appear to be more effective than senna and might be considered as an alternative to this drug. ClincialTrials.gov no: NCT01695850.
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Constipação Intestinal/tratamento farmacológico , Defecação/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Qualidade de Vida , Constipação Intestinal/fisiopatologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Ulcerative colitis (UC) is an increasingly common condition particularly in developed countries. The lack of satisfactory treatment has fueled the search for alternative therapeutic strategies. In recent studies, berberine, a plant alkaloid with a long history of medicinal use in Chinese medicine, has shown beneficial effects against animal models of acute UC. However, UC usually presents as a chronic condition with frequent relapse in patients. How berberine will act on chronic UC remains unclear. In the present study, we adopted dextran sulfate sodium (DSS)-induced chronic relapsing colitis model to assess the ameliorating activity of berberine. Colitis was induced by two cycles of 2.0% DSS for five days followed by 14days of drinking water plus a third cycle consisting of DSS only for five days. The colitis mice were orally administered 20mg/kg berberine from day 13 onward for 30days and monitored daily. The body weight, stool consistency, and stool bleeding were recorded for determination of the disease activity index (DAI). At the end of treatment, animals were sacrificed and samples were collected and subjected to histological, RT-qPCR, Western blot, and LC-MS analyses. Lymphocytes were isolated from spleens and mesenteric lymph nodes (MLN) and cultured for flow cytometry analysis of IL-17 secretion from CD4(+) cells and the Th17 cell differentiation. Results showed that berberine significantly ameliorated the DAI, colon shortening, colon tissue injury, and reduction of colonic expression of tight junction (TJ) protein ZO-1 and occludin of colitis mice. Notably, berberine treatment pronouncedly reduced DSS-upregulated Th17-related cytokine (IL-17 and ROR-γt) mRNAs in the colon. Furthermore, the mRNA expression of IL-6 and IL-23, and the phosphorylation of STAT3 in colon tissues from DSS-treated mice were pronouncedly inhibited by berberine. Moreover, the up-regulation of IL-17 secretion from CD4(+) cells of spleens and MLNs caused by DSS were significantly reversed by berberine treatment. Furthermore, Th17 cell differentiation from naive CD4(+) cells isolated from above DSS colitis mice were suppressed by berberine in a concentration-dependent manner. In summary, we demonstrated for the first time that berberine reduced the severity of chronic relapsing DSS-induced colitis by suppressing Th17 responses. The demonstration of activity in this mouse model supports the possibility of clinical efficacy of berberine in treating chronic UC.
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Berberina/farmacologia , Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Sulfato de Dextrana , Fármacos Gastrointestinais/farmacologia , Interleucina-17/metabolismo , Células Th17/efeitos dos fármacos , Animais , Células Cultivadas , Doença Crônica , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Colo/imunologia , Colo/metabolismo , Colo/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Imunossupressores/farmacologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-23/genética , Interleucina-23/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fenótipo , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Recidiva , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Th17/imunologia , Células Th17/metabolismo , Fatores de TempoRESUMO
Yeast extract (YE), as a non-animal source additive for mammalian cell culture medium, has been widely used for manufacturing of therapeutic proteins. In the present study, one particular YE was found to have significantly improved the specific productivity (q p) of Fc-fusion protein in recombinant Chinese hamster ovary (rCHO) cell culture. In order to elucidate the intracellular effects of YE on protein productivity, steps of the target protein synthesis process were investigated to unveil their variations caused by YE addition. Stepwise analysis on Fc-fusion protein synthesis process showed that YE enhanced Fc-fusion protein gene transcription with cell cycle arrest at G1 phase; mammalian target of rapamycin (mTOR) signaling pathway was activated to enhance the translation of Fc-fusion protein, and the block in post-translational steps of Fc-fusion protein was alleviated by YE addition as well. Our results revealed the responses of multiple protein production steps to the addition of YE and provided a practical guidance for the separation and application of active compounds from hydrolysates.
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Células CHO/metabolismo , Meios de Cultura/química , Fragmentos Fc das Imunoglobulinas/metabolismo , Peptonas/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Animais , Técnicas de Cultura de Células , Cricetulus , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Fragmentos Fc das Imunoglobulinas/genética , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Recombinantes de Fusão/genética , Transcrição Gênica/efeitos dos fármacosRESUMO
OBJECTIVE: To investigate the effect of lowering culture temperature on monoclonal antibody charge variation distribution in Chinese hamster ovary cell cultures. RESULTS: In both batch and fed-batch cultures, lowering the culture temperature decreased the antibody acidic variant levels. The acidic variant levels (defined as variants eluting earlier than the main peak of an antibody during HPLC) at 32 °C were about 10 % lower than those at 37 °C at the end of both batch and fed-batch cultures. Additionally, lowering the culture temperature increased the lysine variant level, which further increased basic variant level. The lysine variant levels at 32 °C were about 8 % (batch culture) and 3 % (fed-batch culture) higher than those at 37 °C at the end of cultures. Real-time PCR results suggests that the decrease in carboxypeptidase B transcription level might be partially responsible for the increased lysine variant level at sub-physiological temperatures. CONCLUSION: Culture temperature exhibits noticeable impact on antibody charge variation distribution, especially the acidic variants and lysine variants.
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Anticorpos Monoclonais/química , Técnicas de Cultura Celular por Lotes/métodos , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/metabolismo , Células CHO , Proliferação de Células , Cromatografia por Troca Iônica , Cricetinae , Cricetulus , TemperaturaRESUMO
Sialic acid levels of therapeutic glycoprotein play an important role in plasma half-life. An undesirable decrease of sialic acid content was observed when we increased Fc-fusion protein productivity fourfold in a GS-CHO cell line by bioprocess optimization. We investigated the potential mechanism for the sialic acid content reduction. We found that limited nucleotide sugar precursor and the extracellular sialidase were not responsible for the reduction of the sialic acid content after titer improvement. Oligosaccharide analysis revealed that the lack of protein galactosylation was the potential cause for the reduction of sialic acid content. Thus we validated this notion by evaluated galactose supplementation in 2 L bioreactors. Cell culture performance was not impacted by addition of up to 40 mM galactose except for the glucose consumption rate. Addition of 20 mM galactose to the bioreactor resulted in the increase of 44 % for total sialic acid content and 20.3 % for sialylated glycans. These data were further validated when the process was run on 200 L scaled bioreactor. These data together show that the galactosylation plays an apparent role in sialylation in our current system.
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Galactose/metabolismo , Fragmentos Fc das Imunoglobulinas/genética , Ácido N-Acetilneuramínico/química , Proteínas Recombinantes de Fusão/metabolismo , Animais , Reatores Biológicos , Células CHO , Técnicas de Cultura de Células , Cricetulus , Humanos , Fragmentos Fc das Imunoglobulinas/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Proteínas Recombinantes de Fusão/genéticaRESUMO
In order to reduce the environmental impact of poly(ethylene terephthalate) (PET) plastic waste, supercritical fluids were used to facilitate effective recovery via improved solvent effects. This work focuses on the mechanisms of supercritical CO2 (ScCO2) during the alcoholysis processing of PET using systematic experiments and molecular dynamics (MD) simulations. The results of the alcoholysis experiment indicated that PET chips can be completely depolymerized within only an hour at 473 K assisted with ScCO2 at an optimal molar ratio of CO2/ethanol of 0.2. Random scission of PET dominates the early stage of the depolymerization reaction process, while specific scission dominates the following stage. Correspondingly, molecular dynamics (MD) simulations revealed that the solubilization and self-diffusion properties of ScCO2 facilitate the transportation of alcohol molecules into the bulk phase of PET, which leads to an accelerated diffusion of both oligomers and small molecules in the system. However, the presence of excessive CO2 has a negative impact on depolymerization by weakening the hydrogen bonding between polyester chain segments and ethanol, as well as decreasing the swelling degree of PET. These data provide a deep understanding of PET degradation by alcohols and the enhancement of ScCO2. It should be expected to achieve an efficient and high-yield depolymerization process of wasted polyesters assisted with ScCO2 at a relatively low temperature.
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Ultralight dark photons constitute a well-motivated candidate for dark matter. A coherent electromagnetic wave is expected to be induced by dark photons when coupled with Standard-Model photons through kinetic mixing mechanism, and should be spatially correlated within the de Broglie wavelength of dark photons. Here we report the first search for correlated dark-photon signals using a long-baseline network of 15 atomic magnetometers, which are situated in two separated meter-scale shield rooms with a distance of about 1700 km. Both the network's multiple sensors and the shields large size significantly enhance the expected dark-photon electromagnetic signals, and long-baseline measurements confidently reduce many local noise sources. Using this network, we constrain the kinetic mixing coefficient of dark photon dark matter over the mass range 4.1 feV-2.1 peV, which represents the most stringent constraints derived from any terrestrial experiments operating over the aforementioned mass range. Our prospect indicates that future data releases may go beyond the astrophysical constraints from the cosmic microwave background and the plasma heating.
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Quantum sensing provides sensitive tabletop tools to search for exotic spin-dependent interactions beyond the standard model, which have attracted great attention in theories and experiments. Here, we develop a technique based on Spin Amplifier for Particle PHysIcs REsearch (SAPPHIRE) to resonantly search for exotic interactions, specifically parity-odd spin-spin interactions. The present technique effectively amplifies exotic interaction fields by a factor of about 200 while being insensitive to spurious magnetic fields. Our studies, using such a quantum amplification technique, explore the parity-violation interactions mediated by a new vector boson in the challenging parameter space (force range between 3 mm and 1 km) and set the most stringent constraints on axial-vector electron-neutron couplings, substantially improving previous limits by five orders of magnitude. Moreover, our constraints on axial-vector couplings between nucleons reach into a hitherto unexplored parameter space. The present constraints complement the existing astrophysical and laboratory studies on potential standard model extensions.
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A mobile Rayleigh Doppler lidar based on double-edge technique is developed for mid-altitude wind observation. To reduce the systematic error, a system-level optical frequency control method is proposed and demonstrated. The emission of the seed laser at 1064 nm is used to synchronize the FPI in the optical frequency domain. A servo loop stabilizing the frequency of the seed laser is formed by measuring the absolute frequency of the second harmonic against an iodine absorption line. And, the third harmonic is used for Rayleigh lidar detection. The frequency stability is 1.6 MHz at 1064 nm over 2 minutes. A locking accuracy of 0.3 MHz at 1064 nm is realized. In comparison experiments, wind profiles from the lidar, radiosonde and European Center for Medium range Weather Forecast (ECMWF) analysis show good agreement from 8 km to 25 km. Wind observation over two months is carried out in Urumqi (42.1°N, 87.1°E), northwest of China, demonstrating the stability and robustness of the system. For the first time, quasi-zero wind layer and dynamic evolution of high-altitude tropospheric jet are observed based on Rayleigh Doppler lidar in Asia.
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Over the past years, persulfate (PS) is widely applied due to their high versatility and efficacy in decontamination and sterilization. While treatment of organic chemicals, remediation of soil and groundwater, sludge treatment, disinfection on pathogen microorganisms have been covered by most published reviews, there are no comprehensive and specific reviews on its application to address diverse sustainability challenges, including solid waste treatment, resources recovery and regeneration of ecomaterials. PS applications mainly rely on direct oxidation by PS itself or the reactive sulfate radical (SO4â¢-) or hydroxyl radical (â¢OH) from the activation of peroxodisulfate (PDS, S2O82-) or peroxymonosulfate (PMS, HSO5-) in SO4â¢--based advanced oxidation processes (SO4â¢--AOPs). From a broader perspective of environmental cleanup and sustainability, this review summarizes the various applications of PS except pollutant decontamination and elaborates the possible reaction mechanisms. Additionally, the differences between PS treatment and conventional technologies are highlighted. Challenges, research needs and future prospect are thus discussed to promote the development of the applications of PS-based oxidation processes in niche environmental fields. In all, this review is a call to pay more attention to the possibilities of PS application in practical resource reutilization and environmental protection except widely reported pollutant degradation.
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Radical Hidroxila , Poluentes Químicos da Água , Radical Hidroxila/química , Compostos Orgânicos , Oxirredução , Esgotos , Solo , Resíduos Sólidos , Sulfatos/química , Poluentes Químicos da Água/químicaRESUMO
Since the first outbreak in December 2019, SARS-CoV-2 has been constantly evolving and five variants have been classified as Variant of Concern (VOC) by the World Health Organization (WHO). These VOCs were found to enhance transmission and/or decrease neutralization capabilities of monoclonal antibodies and vaccine-induced antibodies. Here, we successfully designed and produced a recombinant COVID-19 vaccine in CHO cells at a high yield. The vaccine antigen contains four hot spot substitutions, K417N, E484K, N501Y and D614G, based on a prefusion-stabilized spike trimer of SARS-CoV-2 (S-6P) and formulated with an Alum/CpG 7909 dual adjuvant system. Results of immunogenicity studies showed that the variant vaccine elicited robust cross-neutralizing antibody responses against SARS-CoV-2 prototype (Wuhan) strain and all 5 VOCs. It further, stimulated a TH1 (T Helper type 1) cytokine profile and substantial CD4+ T cell responses in BALB/c mice and rhesus macaques were recorded. Protective efficacy of the vaccine candidate was evaluated in hamster and rhesus macaque models of SARS-CoV-2. In Golden Syrian hamsters challenged with Beta or Delta strains, the vaccine candidate reduced the viral loads in nasal turbinates and lung tissues, accompanied by significant weight gain and relieved inflammation in the lungs. In rhesus macaque challenged with prototype SARS-CoV-2, the vaccine candidate decreased viral shedding in throat, anal, blood swabs over time, reduced viral loads of bronchus and lung tissue, and effectively relieved the lung pathological inflammatory response. Together, our data demonstrated the broadly neutralizing activity and efficacy of the variant vaccine against both prototype and current VOCs of SARS-CoV-2, justifying further clinical development.
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Bubble growth in the polymer extrusion foaming process occurs under a dynamic melt flow. For non-Newtonian fluids, this work successfully coupled the dynamic melt flow simulation with the bubble growth model to realize bubble growth predictions in an extrusion flow. The initial thermophysical properties and dynamic rheological property distribution at the cross section of the die exit were calculated based on the finite element method. It was found that dynamic rheological properties provided a necessary solution for predicting bubble growth during the supercritical CO2 polyethylene terephthalate (PET) extrusion foaming process. The introduction of initial melt stress could effectively inhibit the rapid growth of bubbles and reduce the stable size of bubbles. However, the initial melt stress was ignored in previous work involving bubble growth predictions because it was not available. The simulation results based on the above theoretical model were consistent with the evolution trends of cell morphology and agreed well with the actual experimental results.
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Poly(ethylene-co-octene) (POE) elastomers with different copolymer compositions and molecular weight exhibit quite distinctive foaming behaviors and dimensional stability using supercritical carbon dioxide (CO2) as a blowing agent. As the octene content decreases from 16.54% to 4.48% with constant melting index of 1, both the melting point and crystallinity of POE increase, due to the increase in fraction of ethylene homo-polymerization segment. the foaming window of POE moves to a narrow higher temperature zone from 20-50 °C to 90-110 °C under 11 Mpa CO2 pressure, and CO2 solubility as well as CO2 desorption rate decrease, so that the average cell diameter becomes larger. POE foams with higher octene content have more serious shrinkage problem due to lower compression modulus, weaker crystal structure and higher CO2 permeability. As POE molecular weight increases at similar octene content, there is little effect on crystallization and CO2 diffusion behavior, the foaming window becomes wider and cell density increases, mainly owing to higher polymer melt strength, the volume shrinkage ratio of their foams is less than 20% because of similar higher polymer modulus. In addition, when the initiate expansion ratio is over 17 times, POE foams with longer and thinner cell wall structures are more prone to shrinkage and recovery during aging process, due to more bending deformation and less compression deformation.
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BACKGROUND: Cervical cancer (CC) endangers women's health in the world range. Accumulating studies have revealed the crucial regulatory role of long non-coding RNAs (lncRNAs) in multiple malignancies, including CC. Our study aimed to explore the role of lncRNA double homeobox A pseudogene 8 (DUXAP8) in cervical carcinogenesis. METHODS: Gene expressions in CC were assessed by RT-qPCR. Function experiments and tube formation assays were performed to evaluate the role of DUXAP8 in CC cells. Subcellular fractionation and FISH assays were conducted to determine the subcellular location of DUXAP8. Luciferase reporter, RNA pull down and RIP assays were conducted to investigate the mechanism of DUXAP8. RESULTS: DUXAP8 was notably upregulated in CC cells. Downregulation of DUXAP8 repressed cell malignant behaviors and angiogenesis in CC. Mechanically, DUXAP8 boosted the expression of reticulocalbin-2 (RCN2) through relieving the binding of miR-1297 to RCN2 3'-UTR. Moreover, miR-1297 inhibition and RCN2 overexpression could counteract the inhibitory effects of DUXAP8 knockdown on the malignant phenotypes of CC cells. Besides, enhanced RCN2 expression restored the tumor growth in vivo that was inhibited by DUXAP8 repression. CONCLUSIONS: DUXAP8 promotes malignant behaviors in CC cells via regulating miR-1297/RCN2 axis.