Contact interaction analysis of pion GTMDs Zhang, Jin-Li; Cui, Zhu-Fang; Ping, Jia-Lun ...
The European physical journal. C, Particles and fields,
2021/1, Volume:
81, Issue:
1
Journal Article
Peer reviewed
Open access
A contact interaction is used to calculate an array of pion twist-two, -three and -four generalised transverse light-front momentum dependent parton distribution functions (GTMDs). Despite the ...interaction’s simplicity, many of the results are physically relevant, amongst them a statement that GTMD size and shape are largely prescribed by the scale of emergent hadronic mass. Moreover, proceeding from GTMDs to generalised parton distributions, it is found that the pion’s mass distribution form factor is harder than its electromagnetic form factor, which is harder than the gravitational pressure distribution form factor; the pressure in the neighbourhood of the pion’s core is commensurate with that at the centre of a neutron star; the shear pressure is maximal when confinement forces become dominant within the pion; and the spatial distribution of transversely polarised quarks within the pion is asymmetric. Regarding transverse momentum dependent distribution functions, their magnitude and domain of material support decrease with increasing twist. The simplest Wigner distribution associated with the pion’s twist-two dressed-quark GTMD is sharply peaked on the kinematic domain associated with valence-quark dominance; has a domain of negative support; and broadens as the transverse position variable increases in magnitude.
This study focused on the fabrication and characterization of ammonium metatungstate hydrate (AMT) combined with cobalt(III) acetylacetonate (Co(acac)
3
)-loaded electrospun micro-nanofibers. The ...morphologies, structures, element distribution, through-pore size, and through-pore size distribution of AMT/Co(acac)
3
-loaded PAN/PS micro-nanofibers were investigated by a combination of field emission scanning electron microscopy (FESEM), flourier transformation infrared (FTIR) spectroscopy, energy disperse spectroscopy (EDS), through-pore size analyzer, and so on. These micro-nanofibers have many advantages in their potential application as electro-catalysts. The porous and large thorough-pore will benefit for effective electrolyte penetration, in addition to promoting gas bubbles evolving and releasing from catalyst surface timely.
Natural fiber reinforced composites are currently used in various fields such as automobile, building construction and furniture materials considering the increasing environment pollution caused by ...the extensive use of plastic products. In this study, jute fiber and polylactic acid (PLA) were combined to prepare jute PLA-based biodegradable composites. PLA is one of the most attractive research pursuits among thermoplastic composites due to its excellent biodegradability and the ultimate degradation products of PLA are carbon dioxide and water, which have no pollution to the environment. Basically, the mechanical and thermal performances of the jute/PLA laminated composites were characterized and analyzed in this work. The analytical results on jute/PLA sandwiches reveal that different ply counts and stacking sequences significantly influence the mechanical properties of the composites material. The study on jute/PLA composites will provide quantitative experimental data for potential applications with advantages of lightweight, cost effective, easy manufacture, biodegradable and excellent mechanical properties.
Jute fibers are commonly used as reinforcement in composite materials manufacture due to its excellent mechanical properties. In this study, alkali (NaOH) and silane coupling agent KH570 treatment ...were conducted on component jute nonwovens to improve the bonding strength of jute/PLA composite interface. The jute/PLA composites were prepared from treated jute nonwovens and PLA films by molding method. The results show that alkali treatment can significantly improve the tensile, flexural and dynamic thermomechanical properties of jute/PLA composites. The composites treated with 1% NaOH exhibits the maximum tensile strength while the composites treated with 5% NaOH presents the maximum flexural strength and the minimum loss in the dynamic thermo-mechanical process. Moreover, the tensile and flexural strength of the composite treated with the combination of 5% NaOH-5% KH570 is significantly stronger than that when they act alone. This research can provide an optimal treatment strategy for the jute/PLA degradable composites with higher mechanical and thermos-mechanical tolerance.
As the largest container and resource of metals, sediment has a special role in the fate of metals. Factors influencing bioavailability of heavy metals in sediment have never been comprehensively ...considered and the sediment properties still fail to understand and even controversial. In this review, the mechanisms of sediment properties such as acid-volatile sulfides (AVS), organic matter, texture (clay, silt or sand) and geology, organism behaviors as well as those influencing the bioavailability of metals were analyzed. Under anoxic condition, AVS mainly reduce the solubility and toxicity of metals, while organic matters, Fe–Mn oxides, clay or silt can stabilize heavy metals in elevated oxidative–reductive potential (ORP). Other factors including the variation of pH, redox potential, aging as well as nutrition and the behavior of benthic organism in sediment also largely alter metals mobility and distribution. These factors are often inter-related, and various toxicity assessment methods used to evaluate the bioavailability of trace metals have been also discussed. Additionally, we expect that some novel synthetic materials like polysulfides, nano-materials, provide the substantial amendments for metals pollution in sediment.
•The influencing mechanisms of sediment geochemical properties on heavy metals bioavailability were analyzed.•AVS stabilize heavy metals in anoxic state but OM and Fe-Mn oxides immobilize metals under aerobic condition.•Considering the sediment geochemical properties is needed when establish the model of bioavailability.
Acupuncture is used to induce ovulation in some women with polycystic ovary syndrome, without supporting clinical evidence.
To assess whether active acupuncture, either alone or combined with ...clomiphene, increases the likelihood of live births among women with polycystic ovary syndrome.
A double-blind (clomiphene vs placebo), single-blind (active vs control acupuncture) factorial trial was conducted at 21 sites (27 hospitals) in mainland China between July 6, 2012, and November 18, 2014, with 10 months of pregnancy follow-up until October 7, 2015. Chinese women with polycystic ovary syndrome were randomized in a 1:1:1:1 ratio to 4 groups.
Active or control acupuncture administered twice a week for 30 minutes per treatment and clomiphene or placebo administered for 5 days per cycle, for up to 4 cycles. The active acupuncture group received deep needle insertion with combined manual and low-frequency electrical stimulation; the control acupuncture group received superficial needle insertion, no manual stimulation, and mock electricity.
The primary outcome was live birth. Secondary outcomes included adverse events.
Among the 1000 randomized women (mean SD age, 27.9 3.3 years; mean SD body mass index, 24.2 4.3), 250 were randomized to each group; a total of 926 women (92.6%) completed the trial. Live births occurred in 69 of 235 women (29.4%) in the active acupuncture plus clomiphene group, 66 of 236 (28.0%) in the control acupuncture plus clomiphene group, 31 of 223 (13.9%) in the active acupuncture plus placebo group, and 39 of 232 (16.8%) in the control acupuncture plus placebo group. There was no significant interaction between active acupuncture and clomiphene (P = .39), so main effects were evaluated. The live birth rate was significantly higher in the women treated with clomiphene than with placebo (135 of 471 28.7% vs 70 of 455 15.4%, respectively; difference, 13.3%; 95% CI, 8.0% to 18.5%) and not significantly different between women treated with active vs control acupuncture (100 of 458 21.8% vs 105 of 468 22.4%, respectively; difference, -0.6%; 95% CI, -5.9% to 4.7%). Diarrhea and bruising were more common in patients receiving active acupuncture than control acupuncture (diarrhea: 25 of 500 5.0% vs 8 of 500 1.6%, respectively; difference, 3.4%; 95% CI, 1.2% to 5.6%; bruising: 37 of 500 7.4% vs 9 of 500 1.8%, respectively; difference, 5.6%; 95% CI, 3.0% to 8.2%).
Among Chinese women with polycystic ovary syndrome, the use of acupuncture with or without clomiphene, compared with control acupuncture and placebo, did not increase live births. This finding does not support acupuncture as an infertility treatment in such women.
clinicaltrials.gov Identifier: NCT01573858.
Fiber reinforced composite materials can be seen everywhere in our daily life. The development speed of thermoplastic composites has gradually surpassed that of thermosetting materials because of ...their low density, recyclability and high production efficiency. Polylactic acid (PLA) and jute fibers are two of the most attractive research pursuits in the field of biodegradable materials nowadays. In this work, PLA films and jute nonwovens were made firstly, then biodegradable composite materials were produced combining PLA as the matrix with jute fiber as reinforcement using the film-stacking method. The mechanical properties of the prepared biodegradable materials were characterized by tensile testing and 3-point bending testing. The biodegradable composite materials have great potential applications in various fields with advantages of low cost, easy manufacture, low density and excellent mechanical properties.
Amino acids are known regulators of cellular signaling and physiology, but how they are sensed intracellularly is not fully understood. Herein, we report that each aminoacyl-tRNA synthetase (ARS) ...senses its cognate amino acid sufficiency through catalyzing the formation of lysine aminoacylation (K-AA) on its specific substrate proteins. At physiologic levels, amino acids promote ARSs bound to their substrates and form K-AAs on the ɛ-amine of lysines in their substrates by producing reactive aminoacyl adenylates. The K-AA marks can be removed by deacetylases, such as SIRT1 and SIRT3, employing the same mechanism as that involved in deacetylation. These dynamically regulated K-AAs transduce signals of their respective amino acids. Reversible leucylation on ras-related GTP-binding protein A/B regulates activity of the mammalian target of rapamycin complex 1. Glutaminylation on apoptosis signal-regulating kinase 1 suppresses apoptosis. We discovered non-canonical functions of ARSs and revealed systematic and functional amino acid sensing and signal transduction networks.
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•Amino acids modify ɛ-amines of lysines•Each tRNA synthetase is the aminoacyl transferase of its cognate amino acid•Aminoacylations can be reversed by deacetylases•Aminoacylations transmit amino acid signals to regulate cellular functions
He et al. reveal that tRNA synthetases sense sufficiency of amino acids and act as aminoacyl transferases to modify ɛ-amines of lysines in proteins, with leucylation of RagA/B regulating mTORC1 activity and glutaminylation of ASK1 inhibiting apoptosis. Lysine aminoacylation marks are removed by SIRT1 and SIRT3.
With the progress of society, fiber reinforced composites have become the subject of research in the field of composite materials, in which natural fibers are widely used in the enhancement and ...modification of thermoplastics due to their low density, biodegradation and most wide origins. However, the hydrophilicity of special fiber is the main factor that hinders its bonding with hydrophobic polymer matrix which leads to poor interface compatibility between the fiber/matrix interface. The coupling agent can increase the nonpolarity of the natural fiber and the compatibility between the fiber and the resin. In this study, the composites were fabricated by the film stacking method, and the surface of jute fiber was treated with silane coupling agent so as to prepare jute/polylactic acid composites with good mechanical and thermal properties. The mechanical and thermomechanical results show that the combination of the coupling agent can significantly improve the interfacial bond of the jute/polylactic acid composites, leading to an efficient enhancement of comprehensive performance.
Sugarcane, a cash crop, is easily affected by low temperature, which results in a decrease in yield and sugar production. Breeding a new variety with cold tolerance is an essential strategy to reduce ...loss from cold stress. The identification of germplasms and genes/proteins with cold tolerance is a vital step in breeding sugarcane varieties with cold tolerance via a conventional program and molecular technology. In this study, the physiological and biochemical indices of 22 genotypes of
were measured, and the membership function analysis method was used to comprehensively evaluate the cold tolerance ability of these genotypes. The physiological and biochemical indices of these
genotypes showed a sophisticated response to low temperature. On the basis of the physiological and chemical indices, the genotypes were classified into different cold tolerance groups. Then, the high-tolerance genotype 1027 and the low-tolerance genotype 3217 were selected for DIA-based proteomic analysis by subjecting them to low temperature. From the four comparison groups, 1123, 1341, 751, and 1693 differentially abundant proteins (DAPs) were identified, respectively. The DAPs based on genotypes or treatments participated in distinct metabolic pathways. Through detailed analysis of the DAPs, some proteins related to protein homeostasis, carbohydrate and energy metabolism, amino acid transport and metabolism, signal transduction, and the cytoskeleton may be involved in sugarcane tolerance to cold stress. Furthermore, five important proteins related to cold tolerance were discovered for the first time in this study. This work not only provides the germplasms and candidate target proteins for breeding sugarcane varieties with cold tolerance via a conventional program and molecular breeding, but also helps to accelerate the determination of the molecular mechanism underlying cold tolerance in sugarcane.
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