Mixed Finite Volume Element Method for Vibration Equations of Beam with Structural Damping

In this paper, for the initial and boundary value problem of beams with structural damping, by introducing intermediate variables, the original fourth-order problem is transformed into second-order partial differential equations, and the mixed finite volume element scheme is constructed, and the existence, uniqueness and convergence of the scheme are analyzed. Numerical examples are provided to confirm the theoretical results. In the end, we test the value of δ to observe its influence on the model.

不同饲料原料加工工艺对猪肠道健康的影响

我国饲料产业规模效益已得到充分发挥,饲料产品的利润逐年降低,通过简单数量扩增很难再获得较大的增长。因此必须从饲料品质上突破,根据动物精细饲养的要求对饲料产品进行细分加工,推动饲料加工工艺与动物营养技术融合技术的研究,从而满足市场对饲料加工产品的高品质需求。饲料加工工艺如粉碎、调质和膨化,不仅改变饲料原料理化性质,而且影响到猪肠道健康(腹泻、肠道形态结构、菌群等)。因此,应通过综合评估饲料加工工艺对饲料理化性质(体外)的影响以及在猪生产上(体内)的应用效果,才能精准优化不同饲料原料加工工艺参数。文章主要对不同饲料原料加工工艺在猪肠道健康中的研究进行综述,为猪生产中饲料加工工艺及参数的选择提供参考。

Preparation and characterization of atrazine-loaded biodegradable PLGA nanospheres

Atrazine is the second mostly used herbicide in USA,but low utilization ratio causes severe environmental problem,so controlled release system is highly needed in order to minimize the negative impact on environment.In this paper,a herbicide delivery system,atrazine-loaded poly(lactic-co-glycolic acid)(PLGA)nanoparticles(NPs)were prepared by forming an oilin-water emulsion using the emulsion-solvent evaporation method.By varying the preparation conditions of PLGA-NPs,such as sonication time,surfactant content,solvent fraction,and polymer content,the particle sizes of the PLGA-NPs were well controlled from 204 to 520 nm.The morphology and size distribution of PLGA-NPs were evaluated using dynamic light scattering(DLS)and scanning electron microscopy(SEM).Both the encapsulation efficiency and release profile of the herbicide from the PLGA-NPs were typically evaluated by using 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine(atrazine,ATZ)as the model.ATZ encapsulation efficiency within the PLGA-NPs was ranged from 31.6 to 50.5%.The release profiles of ATZ-loaded PLGA-NPs exhibited a much slower release rate in comparison with that of pure herbicide.The results demonstrated that the prepared PLGA-NPs had a high encapsulation efficiency and slow release rate,which could be used as a promising herbicide release system in agriculture to diminish the impact on the environment and minimize the potential harm to the farmers.

Tyrosine promotes anthocyanin biosynthesis in pansy(Viola×wittrockiana)by inducing ABA synthesis

Viola×wittrockiana(pansy)is an important ornamental plant,particularly during winter and spring.In previous studies,we found that the tyrosine decarboxylase gene of pansy(VwTYDC)was expressed differently in blotched and non-blotched areas of pansy petals,suggesting that tyrosine may have a role in anthocyanin biosynthesis.In this study,we found that virus-induced gene silencing of VwTYDC caused an accumulation of pink pigmentation in pansy petals.Likewise,exogenous tyrosine treatment(TYRT)induced the formation of black stripes in nonblotched petal areas.Metabolome analysis indicated that the contents of two anthocyanins,cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside,increased significantly in the TYRT areas.RT-qPCR results revealed that the anthocyanin-related genes VwHCT,VwC3′H,VwCHS,and VwUGT were upregulated in the same areas.Transcriptome analysis revealed that four genes involved in the abscisic acid(ABA)biosynthesis pathway(VwNCED,VwABA2,VwAAO3,and VwCYP707A)were significantly upregulated in the same TYRT areas.ABA content was measured by ESI-HPLCMS/MS,and ABA content was significantly higher in TYRT areas than in control areas.In addition,when exogenous ABA was spread onto nonblotched petal areas,anthocyanin biosynthesis genes were upregulated just as with tyrosine.Thus,transcriptome and metabolite analyses revealed a possible novel regulatory network for anthocyanin biosynthesis in which tyrosine induces ABA synthesis and ABA then promotes anthocyanin biosynthesis in pansy petals.

Enhancing in-field performance of GdBCO coated conductors by cooperative irradiation with Ti ions and protons

Irradiation can accurately manipulate defects and adjust pinning landscapes within REBa_(2)Cu_(3)O_(7-δ) (REBCO, RE: rare earths) coated conductors (CCs). This study reports a productive method to dramatically boost the in-field critical current density (J_(c) ) for GdBCO CCs using cooperative irradiation with Ti ions and protons. Remarkably, the in-field J_(c) of commercial CCs can be almost doubled at a wide range of temperatures and magnetic fields. Defects of various sizes induced by cooperative irradiation are more uniform distribution through the entire GdBCO film to improve the vortex pinning characteristics, thereby enhancing the in-field performance of the GdBCO CC. This method highlights how combining different particle irradiation types can tailor defect size and distribution, optimizing pinning landscapes for commercial REBCO CCs.

L-leucine stimulates glutamate dehydrogenase activity and glutamate synthesis by regulating mTORC1/SIRT4 pathway in pig liver

The liver is the most essential organ for the metabolism of ammonia, in where most of ammonia is removed by urea and glutamine synthesis. Regulated by leucine, glutamate dehydrogenase(GDH) catalyzes the reversible inter-conversion of glutamate to ammonia. To determine the mechanism of leucine regulating GDH, pigs weighing 20 ± 1 kg were infused for 80 min with ammonium chloride or alanine in the presence or absence of leucine. Primary pig hepatocytes were incubated with or without leucine. In the in vivo experiments with either ammonium or alanine as the nitrogen source, addition of leucine significantly inhibited ureagenesis and promoted the production of glutamate and glutamine in the perfused pig liver(P < 0.05). Similarly, leucine stimulated GDH activity and inhibited sirtuin4(SIRT4)gene expression(P < 0.01). Leucine could also activate mammalian target of rapamycin complex 1(m TORC1) signaling(P < 0.05), as evidenced by the increased phosphorylation levels of ribosomal protein S6 kinase 1(S6 K1) and ribosomal protein S6(S6). Interestingly, the leucine-induced m TORC1 pathway activation suitably correlated with increased GDH activity and decreased expression of SIRT4.Similar results were observed in primary cultured hepatocytes. Notably, leucine exerted no significant change in GDH activity in SIRT4-deficient hepatocytes(P > 0.05), while m TORC1 signaling was activated.Leucine exerted no significant changes in both GDH activity and SIRT4 gene expression in rapamycin treated hepatocytes(P > 0.05). In conclusion, L-leucine increases GDH activity and stimulates glutamate synthesis from different nitrogen sources by regulating m TORC1/SIRT4 pathway in the liver of pigs.

TSUNAMI:Translational Bioinformatics Tool Suite for Network Analysis and Mining

Gene co-expression network(GCN)mining identifies gene modules with highly correlated expression profiles across samples/conditions.It enables researchers to discover latent gene/molecule interactions,identify novel gene functions,and extract molecular features from certain disease/condition groups,thus helping to identify disease bio-markers.However,there lacks an easy-to-use tool package for users to mine GCN modules that are relatively small in size with tightly connected genes that can be convenient for downstream gene set enrichment analysis,as well as modules that may share common members.To address this need,we developed an online GCN mining tool package:TSUNAMI(Tools SUite for Network Analysis and MIning).TSUNAMI incorporates our state-of-the-art lmQCM algorithm to mine GCN modules for both public and user-input data(microarray,RNA-seq,or any other numerical omics data),and then performs downstream gene set enrichment analysis for the identified modules.It has several features and advantages:1)a user-friendly interface and real-time co-expression network mining through a web server;2)direct access and search of NCBI Gene Expression Omnibus(GEO)and The Cancer Genome Atlas(TCGA)databases,as well as user-input gene ex-pression matrices for GCN module mining;3)multiple co-expression analysis tools to choose from,all of which are highly flexible in regards to parameter selection options;4)identified GCN modules are summarized to eigengenes,which are convenient for users to check their correlation with other clinical traits;5)integrated downstream Enrichr enrichment analysis and links to other gene set enrichment tools;and 6)visualization of gene loci by Circos plot in any step of the process.The web service is freely accessible through URL:https://biolearns.medicine.iu.edu/.Source code is available at https://github.com/huangzhii/TSUNAMI/.