The micro-nano composite structure can endow separation membranes with special surface properties, but it often has the problems of inefficient preparation process and poor structural stability. In ...this work, a novel atomization-assisted nonsolvent induced phase separation method, which is also highly efficient and very simple, has been developed. By using this method, a bicontinuous porous microfiltration membrane with robust micro-nano composite structure was obtained via commercially available polymers of polyacrylonitrile and polyvinylpyrrolidone. The formation mechanism of the micro-nano composite structure was proposed. The microphase separation of polyacrylonitrile and polyvinylpyrrolidone components during the atomization pretreatment process and the hydrogen bonding between polyacrylonitrile and polyvinylpyrrolidone molecules should have resulted in the nano-protrusions on the membrane skeleton. The membrane exhibits superhydrophilicity in air and superoleophobicity underwater. The membrane can separate both surfactant-free and surfactant-stabilized oil-in-water emulsions with high separation efficiency and permeation flux. With excellent antifouling property and robust microstructure, the membrane can easily be recycled for long-term separation. Furthermore, the scale-up verification from laboratory preparation to continuous production has been achieved. The simple, efficient, cost-effective preparation method and excellent membrane properties indicate the great potential of the developed membranes in practical applications.
Tibetan pigs show a widespread distribution in plateau environments and exhibit striking physiological and phenotypic differences from others pigs for adaptation to hypoxic conditions. However, the ...regulation of mRNAs and metabolites as well as their functions in the alveolar type II epithelial (ATII) cells of Tibetan pigs remain undefined. Herein, we carried out integrated metabolomic and transcriptomic profiling of ATII cells between Tibetan pigs and Landrace pigs across environments with different oxygen levels to delineate their signature pathways. We observed that the differentially accumulated metabolites (DAMs) and differentially expressed genes (DEGs) profiles displayed marked synergy of hypoxia-related signature pathways in either Tibetan pigs or Landrace pigs. A total of 1,470 DEGs shared between normoxic (TN, ATII cells of Tibetan pigs were cultured under 21% O
; LN, ATII cells of Landrace pigs were cultured under 21% O
) and hypoxic (TL, ATII cells of Tibetan pigs were cultured under 2% O
; LL, ATII cells of Landrace pigs were cultured under 2% O
) groups and 240 DAMs were identified. Functional enrichment assessment indicated that the hypoxia-related genes and metabolites were primarily involved in glycolysis and aldosterone synthesis and secretion. We subsequently constructed an interaction network of mRNAs and metabolites related to hypoxia, such as guanosine-3', 5'-cyclic monophosphate, Gly-Tyr, and phenylacetylglycine. These results indicated that mitogen-activated protein kinase (MAPK) signaling, aldosterone synthesis and secretion, and differences in the regulation of
and adenosine may play vital roles in the better adaptation of Tibetan pigs to hypoxic environments relative to Landrace pigs. This work provides a new perspective and enhances our understanding of mRNAs and metabolites that are activated in response to hypoxia in the ATII cells of Tibetan pigs.
The properties of zein nanoparticles formed by anti-solvent precipitation are affected by solvent type, solvent composition, mixing method, and dilution ratio. Ultrasound is a non-thermal technology ...and can be used to assist in the fabrication of zein nanoparticles. Curcumin is a natural bioactive compound that has health benefits for humans. The objectives of this study were 1) to evaluate the effect of ethanol concentration, the ratio of the dispersed phase to continuous phase, and the amplitude of ultrasound on the properties of zein nanoparticles and 2) to assess the encapsulation and stability of curcumin in the zein nanoparticles via ultrasonic treatment.
Zein nanoparticles were fabricated by ultrasonic treatment with various initial ethanol concentrations in the continuous phase, volume ratios of the dispersed to continuous phases, and ultrasound amplitudes. The particle size decreased as the concentration of ethanol in the continuous phase decreased. Curcumin was encapsulated by selected ultrasonic treatments and the particle size, encapsulation efficiency, and XRD of zein-curcumin nanoparticles were analyzed.
The findings from this study provide insights and means for manipulating zein nanoparticles by adjusting processing conditions when using ultrasound. Also, encapsulation of bioactive compounds such as curcumin can be improved using controlled ultrasound treatment.
•Zein nanoparticles were fabricated by ultrasonic treatment with various ratios of dispersed phase to continuous phase.•Zein-curcumin nanoparticles were fabricated by ultrasonic treatment with different initial ethanol concentrations.•The particle size increased as the ethanol concentration in the continuous phase increased.•The encapsulated curcumin was more stable toward heat and light than free curcumin.•At critical ethanol concentration, the nanoparticle formation and curcumin encapsulation changed significantly.
A microfluidic chip is a micro-reactor that precisely manipulates and controls fluids. Zein is a group of prolamines extracted from corn that can form self-assembled nanoparticles in water or a low ...concentration of ethanol in a microfluidic chip. However, the zein nanoparticles have stability issues, especially in a neutral pH environment due to the proximity of the isoelectric point. This study was designed 1) to evaluate the effect of octenyl succinic anhydride (OSA) modified starch on the stability of zein nanoparticles formed using a microfluidic chip and 2) to apply the zein-OSA starch for encapsulation of nisin and evaluate its anti-microbial activity in a model food matrix. A T-junction configuration of the microfluidic chip was used to fabricate the zein nanoparticles using 1% or 2% zein solution and 0–10% (w/w) of OSA starch solution. The stability of the nanoparticles in various ionic strength environments was assessed. Encapsulation efficiency and anti-microbial activity of nisin in the zein nanoparticles against Listeria monocytogenes in a fresh cheese were measured. As the concentration of OSA starch increased from 0 to 10%, effective diameter increased from 117.8 ± 14.5 to 198.7 ± 13.9 nm without affecting polydispersity indexes and zeta-potential changed toward that of the modified starch indicating the zein surface coverage by the OSA starch. The zein-OSA starch nanoparticle complexes were more stable at various sodium chloride concentrations than the zein nanoparticles without OSA starch. The encapsulation efficiency of nisin was positively correlated with the OSA starch concentration. The anti-microbial activity of nisin in the fresh cheese also increased until 3-days of storage as the concentration of the OSA starch increased, which presented both a potential and challenge toward applications.
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•Microfluidic chip formed zein nanoparticles with OSA-modified starch.•Zein nanoparticle size and stability were affected by zein and modified starch concentration.•Nisin was encapsulated in the zein nanoparticles via microfluidic chip.•Anti-microbial activity of nisin was improved by the encapsulation.
Alternative splicing (AS) allows the generation of multiple transcript variants from a single gene and affects biological processes by generating protein diversity in organisms. In total, 41,642 AS ...events corresponding to 9,924 genes were identified, and SE is the most abundant alternatively spliced type. The analysis of functional categories demonstrates that alternatively spliced differentially expressed genes (DEGs) were enriched in the MAPK signaling pathway and hypoxia-inducible factor 1 (HIF-1) signaling pathway. Proteoglycans in cancer between the normoxic (21% O
2
, TN and LN) and hypoxic (2% O
2
, TL and LL) groups, such as
SLC2A1, HK1, HK2, ENO3
, and
PFKFB3
, have the potential to rapidly proliferate alveolar type II epithelial (ATII) cells by increasing the intracellular levels of glucose and quickly divert to anabolic pathways by glycolysis intermediates under hypoxia.
ACADL, EHHADH
, and
CPT1A
undergo one or two AS types with different frequencies in ATII cells between TN and TL groups (excluding alternatively spliced DEGs shared between normoxic and hypoxic groups), and a constant supply of lipids might be obtained either from the circulation or
de novo
synthesis for better growth of ATII cells under hypoxia condition.
MCM7
and
MCM3
undergo different AS types between LN and LL groups (excluding alternatively spliced DEGs shared between normoxic and hypoxic groups), which may bind to the amino-terminal PER-SIM-ARNT domain and the carboxyl terminus of
HIF
-
1
α to maintain their stability. Overall, AS and expression levels of candidate mRNAs between Tibetan pigs and Landrace pigs revealed by RNA-seq suggest their potential involvement in the ATII cells grown under hypoxia conditions.
Understanding the signaling pathway regulatory mechanisms in type II alveolar epithelial (ATII) cells, the progenitor cells responsible for proliferating and regenerating type I alveolar epithelial ...(ATI) and ATII cells, in Tibetan pigs is beneficial for exploring methods of preventing and repairing cellular damage during hypoxia. We simulated a hypoxic environment (2% O
2
) for culture ATII cells of Tibetan pigs and Landrace pigs, with cells cultured under normoxic conditions (21% O
2
) as a control group, and performed integrated analysis of circular RNA (circRNA)–microRNA (miRNA)–messenger RNA (mRNA) regulatory axes by whole-transcriptome sequencing. Functional enrichment analysis indicated that the source genes of the differential expressed circRNAs (DEcircRNAs) were primarily involved in cell proliferation, cellular processes, and cell killing. A series of DEcircRNAs were derived from inhibitors of apoptosis proteins and led to a key autonomous effect as modulators of cell repair in Tibetan pigs under hypoxia. The significant higher expression of
COL5A1
in TL groups may inhibited apoptosis of ATII cells in Tibetan pigs under lower oxygen concentration, and may lead their better survive in the hypoxia environment. In addition, a competing endogenous RNA (ceRNA) network of functional interactions was constructed that included novel_circ_000898-ssc-miR-199a-5p-
CAV
1 and novel_circ_000898-ssc-miR-378-
BMP
2, based on the node genes ssc-miR-199a-5p and ssc-miR-378, which may regulate multiple miRNAs and mRNAs that mediate endoplasmic reticulum (ER) stress-induced apoptosis and inflammation and attenuate hypoxia-induced injury in ATII cells under hypoxic conditions. These results broaden our knowledge of circRNAs, miRNAs, and mRNAs associated with hypoxia and provide new insights into the hypoxic response of ATII cells in Tibetan pigs.
Degradation of poly (butylene succinate-co-terephthalate) (PBST) mulch film in the vast cotton field in the dry and windy plain has been studied. The films within 3 months' use which were above the ...soil and far away from the plant were selected collected as they were under closely identical outdoor degradation conditions. In macro mechanical properties, the quick decay of the ductility was the most obvious change of the mulch film in outdoor use. The elongation at break in transverse direction (TD) decreased faster than that in machine direction (MD). From micro view, chemical groups are almost retained within 3 months, while three kinds of changes in the polymer chain have been observed: (a) most additives are lost after 1 month's use; (b) chain slightly hydrolysis, of which far less than 1 break per chain occurs at the end of the 3rd month; (c) chain crosslinks, of which there are ∼1.3, 4.1 and 5.2 crosslink points per chain in average after 1, 2 and 3 months' use. The chain crosslink of the PBST is considered to be the main reason for the big decrease of the mechanical property, especially the ductility of the film, and then the main reason for the large-scale breakage of the film during 1∼2 months in Xinjiang. UV screening agent which has a strong adhesion to the polymer should be considered to solve the mulch film problem in the dry and windy plain.
•Accurate ductility decay of the muddy mulch film is got.•Most additives are lost at the time scale of ∼1 month.•Chains hydrolyze slightly, far less than 1 break per chain at the 3rd month.•Number of crosslink are ∼1.3, 4.1 and 5.2 points per chain after 1, 2 and 3 months.•Crosslink is the crucial factor for mulch film problem.
The function of alveolar type II epithelial (ATII) cells is severely hampered by oxygen deficiency, and understanding the regulatory mechanisms controlling responses to hypoxia may assist in ...relieving injury induced by hypoxia. In this study, we cultured ATII cells from Tibetan pigs and Landrace pigs under hypoxic and normoxic environments to screen for differentially expressed (DE) lncRNAs, DEmiRNAs, and construct their associated ceRNA regulatory networks in response to hypoxia. Enrichment analysis revealed that target genes of DElncRNAs of Tibetan pigs and Landrace pig between the normoxic (TN, LN) and hypoxic (TL, LL) groups significantly enriched in the proteoglycans in cancer, renal cell carcinoma, and erbB signaling pathways, while the target genes of DEmiRNAs were significantly enriched in the axon guidance, focal adhesion, and mitogen-activated protein kinase (MAPK) signaling pathways. Hypoxia induction was shown to potentially promote apoptosis by activating the focal adhesion/PI3K-Akt/glycolysis pathway. The ssc-miR-20b/MSTRG.57127.1/ssc-miR-7-5p axis potentially played a vital role in alleviating hypoxic injury by regulating ATII cell autophagy under normoxic and hypoxic conditions. MSTRG.14861.4-miR-11971-z-CCDC12, the most affected axis, regulated numerous RNAs and may thus regulate ATII cell growth in Tibetan pigs under hypoxic conditions. The ACTA1/ssc-miR-30c-3p/MSTRG.23871.1 axis is key for limiting ATII cell injury and improving dysfunction and fibrosis mediated by oxidative stress in Landrace pigs. Our findings provide a deeper understanding of the lncRNA/miRNA/mRNA regulatory mechanisms of Tibetan pigs under hypoxic conditions.
In recent years, rubber toughened polypropylene (PP) blends have been extensively investigated with special regard to the importance of PP matrix properties (e.g., crystal morphology and structure) ...in tailoring the toughening efficiency. Unfortunately, although high melt flowability is indispensable to the processing of polymers into complex thin-wall products, it remains a huge challenge to achieve a marvelous balance between stiffness and toughness in the blends with relatively low matrix molecular weight. Herein, taking PP/EPR (ethylene-propylene copolymer) blends as an example, the combined effects of matrix molecular weight and crystallinity on the mechanical properties of PP/EPR blends have been examined in both experiment and theory. The experimental results show that decreasing molecular weight leads to significant deterioration in notched impact toughness, tensile strength and Young's modulus. Impressively, the toughness loss caused by the decrease of molecular weight can be well-compensated by a slight reduction in the matrix crystallinity, without evidently sacrificing the strength and modulus, demonstrating an improved stiffness-toughness balance. Theoretical analysis indicates that the impact toughness of PP/EPR blends is heavily dependent on the chain entanglement density (ve) of PP matrix, and a linear relationship between critical interparticle distance (IDc) and the ve1/3 has been verified from both experiment and theory. Moreover, it is interesting to find that decreasing matrix crystallinity can increase the ve of low-molecular-weight PP matrix, which enables the effective toughening at lower concentration of EPR and thus gives rise to less loss in the strength and modulus. We believe this work not only gives a new insight into the role of chain entanglement in the toughening but also provides a promising guidance for the design of high-performance PP with high melt flowability.
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•Combined effects of Mn and crystallinity on the toughening efficiency of PP/EPR blends were studded.•The relationship between the IDc and ve of PP matrix i.e. IDc ∼ ve1/3, was given for the first time.•Matrix with higher Mn or lower crystallinity has higher ve, exhibiting larger IDc.•Toughness loss caused by decreasing Mn can be compensated by reducing crystallinity.•Low-viscosity PP/EPR blends with good toughness-stiffness balance were obtained.
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