Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample

Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each proxy.Here,we developed a method by which each proxy can be measured in the same sample.First,the sample is polished for ring width meas-urement.After obtaining the ring width data,the sample is cut to form a 1-mm-thick wood plate.The sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray beam.Simultaneously,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,i.e.the density and the element content are obtained.Then,cellulose is isolated from the 1-mm wood plate by removal of lignin,and hemicellulose.After producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)analysis.Based on this method,RW,density,elemental composition,δ^(13)C,and δ^(18)O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research.

Puerariae Radix protects against ulcerative colitis in mice by inhibiting NLRP3 inflammasome activation

Ulcerative colitis(UC)is a common inflammatory disease of the gastrointestinal tract.Traditional Chinese medicine(TCM)has long been used in Asia as a treatment for UC and Puerariae Radix(PR)is a reliable anti-diarrheal therapy.The aims of this study were to investigate the protective effect of PR using the dextran sulfate sodium salt(DSS)-induced UC model in mice and identify molecular mechanisms of PR action.The chemical constituents of PR via ultra-performance liquid chromatography/tandem mass spectrometry and identified potential PR and UC targets using a network pharmacology(NP)approach were obtained to guide mouse experiments.A total of 180 peaks were identified from PR including 48 flavonoids,46 organic acids,14 amino acids,8 phenols,8 carbohydrates,7 alkaloids,6 coumarins and 43 other constituents.NP results showed that caspase-1 was the most dysregulated of the core genes associated with UC.A PR dose of 0.136 mg/g administered to DSS treated mice reversed weight loss and decreased colon lengths found in UC mice.PR also alleviated intestinal mucosal shedding,inflammatory cell infiltration and mucin loss.PR treatment suppressed upregulation of NOD-like receptor protein 3(NLRP3),cysteinyl aspartate-specific proteases-1(caspase-1),apoptosis-associated speck-like(ASC)and gasdermin D(GSDMD)at both the protein and m RNA expression levels.The addition of a small molecule dual-specificity phosphatase inhibitor NSC 95397 inhibited the positive effects of PR.These results indicated that PR exerts a protective effect on DSS-induced colitis by inhibiting NLRP3 inflammasome activation in mice.

Dietary Epimedium extract supplementation improves intestinal functions and alters gut microbiota in broilers

Background Growth-promoting antibiotics have been banned by law in the livestock and poultry breeding industry in many countries.Various alternatives to antibiotics have been investigated for using in livestock.Epimedium(EM)is an herb rich in flavonoids that has many beneficial effects on animals.Therefore,this study was planned to explore the potential of EM as a new alternative antibiotic product in animal feed.Methods A total of 7201-day-old male broilers(Arbor Acres Plus)were randomly divided into six groups and fed basal diet(normal control;NC),basal diet supplemented with antibiotic(75 mg/kg chlortetracycline;CTC),and basal diet supplemented with 100,200,400 or 800 mg/kg EM extract for 6 weeks(EM100,EM200,EM400 and EM800 groups).The growth performance at weeks 3 and 6 was measured.Serum,intestinal tissue and feces were collected to assay for antioxidant indexes,intestinal permeability,lactic acid and short-chain fatty acids(SCFAs)profiles,microbial composition,and expression of intestinal barrier genes.Results The average daily feed intake in CTC group at 1-21 d was significantly higher than that in the NC group,and had no statistical difference with EM groups.Compared with NC group,average daily gain in CTC and EM200 groups increased significantly at 1-21 and 1-42 d.Compared with NC group,EM200 and EM400 groups had significantly decreased levels of lipopolysaccharide and D-lactic acid in serum throughout the study.The concentrations of lactic acid,acetic acid,propionic acid,butyric acid and SCFAs in feces of birds fed 200 mg/kg EM diet were significantly higher than those fed chlortetracycline.The dietary supplementation of chlortetracycline and 200 mg/kg EM significantly increased ileal expression of SOD1,Claudin-1 and ZO-1 genes.Dietary supplemented with 200 mg/kg EM increased the relative abundances of g_NK4A214_group and Lactobacillus in the jejunal,while the relative abundances of Microbacterium,Kitasatospora,Bacteroides in the jejunal and Gallibacterium in the ileum decreased.Conclusion Supplementation with 200 mg/kg EM extract improved the composition of intestinal microbiota by regulating the core bacterial genus Lactobacillus,and increased the concentration of beneficial metabolites lactic acid and SCFAs in the flora,thereby improving the antioxidant capacity and intestinal permeability,enhancing the function of tight junction proteins.These beneficial effects improved the growth performance of broilers.

Selenium deficiency induces spleen pathological changes in pigs by decreasing selenoprotein expression,evoking oxidative stress,and activating inflammation and apoptosis

Background:The immune system is one aspect of health that is affected by dietary selenium(Se)levels and selenoprotein expression.Spleen is an important immune organ of the body,which is directly involved in cellular immunity.However,there are limited reports on Se levels and spleen health.Therefore,this study established a Se-deficient pig model to investigate the mechanism of Se deficiency-induced splenic pathogenesis.Methods:Twenty-four pure line castrated male Yorkshire pigs(45 days old,12.50±1.32 kg,12 full-sibling pairs)were divided into two equal groups and fed Se-deficient diet(0.007 mg Se/kg)or Se-adequate diet(0.3 mg Se/kg)for 16 weeks.At the end of the trial,blood and spleen were collected to assay for erythroid parameters,the osmotic fragility of erythrocytes,the spleen index,histology,terminal deoxynucleotidyl transferase nick-end labeling(TUNEL)staining,Se concentrations,the selenogenome,redox status,and signaling related inflammation and apoptosis.Results:Dietary Se deficiency decreased the erythroid parameters and increased the number of osmotically fragile erythrocytes(P<0.05).The spleen index did not change,but hematoxylin and eosin and TUNEL staining indicated that the white pulp decreased,the red pulp increased,and splenocyte apoptosis occurred in the Se deficient group.Se deficiency decreased the Se concentration and selenoprotein expression in the spleen(P<0.05),blocked the glutathione and thioredoxin antioxidant systems,and led to redox imbalance.Se deficiency activated the NF-κB and HIF-1αtranscription factors,thus increasing pro-inflammatory cytokines(IL-1β,IL-6,IL-8,IL-17,and TNF-α),decreasing anti-inflammatory cytokines(IL-10,IL-13,and TGF-β)and increasing expression of the downstream genes COX-2 and iNOS(P<0.05),which in turn induced inflammation.In addition,Se-deficiency induced apoptosis through the mitochondrial pathway,upregulated apoptotic genes(Caspase3,Caspase8,and Bak),and downregulated antiapoptotic genes(Bcl-2)(P<0.05)at the mRNA level,thus verifying the results of TUNEL staining.Conclusions:These results indicated that Se deficiency induces spleen injury through the regulation of selenoproteins,oxidative stress,inflammation and apoptosis.

Enhanced high-temperature mechanical properties of laser-arc hybrid additive manufacturing of Al-Zn-Mg-Cu alloy via microstructure control

Recently,rapid and cost-effective additive manufacturing solutions for lightweight aluminum alloys with excellent high-temperature mechanical properties have been increasingly in demand.In this study,we combined laser-arc hybrid additive manufacturing with solution and artificial aging treatments to achieve Al-Zn-Mg-Cu alloy with favorable high-temperature strength via microstructure control.Hydrogen pores became the major defect in the as-deposited and heat-treated specimens.The continuous distribution of eutectics with hard-brittle characteristics at the grain boundaries was destructed following heat treat-ment.High-densityηprecipitates were uniformly dispersed in the heat-treated Al-Zn-Mg-Cu alloy,whereas appeared coarsened and dissolved at 473 K,owing to the rapid diffusion of Zn and Mg.The average 0.2%yield strength(318±16 MPa)and ultimate tensile strength(362±20 MPa)at 473 K af-ter heat treatment were enhanced by approximately 58%and 51%,respectively,compared to those of the as-deposited specimen.In addition,theηprecipitates contributed to lattice distortions and strain fields,which prevented dislocation motion and increased slip deformation resistance at high temper-atures.The as-deposited specimen exhibited intergranular fracture at 473 K,with cracks preferring to propagate along the aggregated eutectics.However,crack propagation proceeded in the sections with more pores in the heat-treated specimen.Our approach may provide a valid option for achieving alu-minum alloys with excellent high-temperature mechanical properties.

具有优越镍-锌电池性能的低结晶镍钴氢氧化物

因具有大量的晶界和离子扩散通道,低结晶度的电极活性材料有望在储能领域中实现更好的性能.然而在大多数应用中通常是结晶良好的样品具有更好的稳定性,稳定性较差限制了低结晶样品在相关研究领域的应用.本文利用一种溶剂热法调控N-甲基吡咯烷酮和水混合溶剂的体积比以合成低结晶度的镍钴氢氧化物(NiCo-OH-L).研究发现,将合成的镍钴氢氧化物用作镍-锌电池正极时,NiCo-OH-L不仅表现出与高结晶度的同类样品相当的循环稳定性能,而且在1-50 A g^(-1)的电流范围内显示出更高的容量以及容量保持率.其优异的电化学性能可归因于低结晶的结构,显著提高的比表面积和降低的电荷转移电阻.此外,NiCo-OH-L的钴组分进一步提高了倍率和循环稳定性能.NiCo-OH-L在1 A g^(-1)时的比容量达到238.9 mA h g^(-1),当电流密度升至50 A g^(-1)时的容量仍有116.4 mA h g^(-1),显示出高容量和高倍率性能.不仅如此,由NiCo-OH-L组装成的镍-锌电池在不同的电流和循环周期下也表现出较高的性能.

Carotenoid enrichment in eggs:From biochemistry perspective

The emergence of safe and functional eggs for consumer acceptance has gained focus.The production of carotenoid-enriched eggs has received attention due to its multifunctional biological properties.Nutritional modification of laying hens’diet can be a strategy to produce such eggs.This review presents the chemistry of carotenoids in nature and eggs,the accumulation process of carotenoids into eggs,and the functions of carotenoids in eggs.Our findings showed that carotenoids can be deposited into the egg and contribute to improving its nutritive value.The biosynthesis,chemical structure,and metabolism pathways of carotenoids lead to the deposition of carotenoids into eggs in their original or metabolized forms.Also,some factors modulate the efficiency of carotenoids in fowls before accumulation into eggs.Carotenoid-enriched eggs may be promising,ensuring the availability of highly nutritive eggs.However,further studies are still needed to comprehend the full metabolism process and the extensive functions of carotenoids in eggs.

基于手性大环主体的对映选择性识别

手性均一性是生命体系的基本物质结构特征,这导致手性对映体分子的识别和区分在许多与生命健康相关的领域都具有重要意义.大环主体是进行分子识别的重要工具,而通过构筑手性大环主体来实现对手性对映体客体的识别和区分一直是超分子化学研究的重要课题.近年来,随着大环主客体化学的蓬勃发展,基于手性大环主体的对映选择性识别也取得长足进步.本文概述了手性大环的常用构筑策略,并重点综述了具有代表性的手性大环主体以及它们的对映选择性识别能力,旨在激发具有优异对映选择性识别和区分能力的大环主体的开发和应用.最后总结了这一领域目前存在的挑战和发展前景.

Surface engineering of titania nanotubes incorporated with double-layered extracellular vesicles to modulate inflammation and osteogenesis

Titania nanotubes(TNT)generated on titanium implant are emerged as important modification technique to facilitate bone regeneration.Mesenchymal stem cells(MSCs)-derived exosomes are membrane bound extracellular vesicles(EVs),which play an important role in tissue regeneration.The objective of this study was to generate an EVs hybrid TNT aiming at regulating inflammation,MSCs recruitment and osteogenesis.We isolated EVs from MSCs(MSCs EVs)and 3-day osteogenically differentiated MSCs(3d EVs).MSC EVs and 3d EVs exhibited round morphology under TEM,which also showed robust internalization by human bone marrow derived MSCs(hBMSCs).Next,we fabricated 3d EVs/MSC EVs hybrid TNT.When inflammatory macrophages were co-cultured with EVs hybrid TNT,the gene and protein expression of inflammatory cytokine were significantly reduced.Macrophage morphology was also examined by confocal laser scanning microscopy(CLSM)and scanning electron microscopy(SEM).Further migratory ability study using hBMSCs indicated significant enhancement of MSCs migration in EVs hybrid TNT.In addition,we further demonstrated significant increase of osteogenic differentiation of hBMSCs in EVs hybrid TNT.This study suggests that EVs hybrid TNT may serve as a viable therapeutic approach to enhance osteogenesis and bone regeneration.

Deforming generalized cylinders without self-intersection by means of a parametric center curve

Large-scale deformations of a tubular object, or generalized cylinder, are often defined by a target shape for its center curve, typically using a parametric target curve. This task is non-trivial for free-form deformations or direct manipulation methods because it is hard to manually control the centerline by adjusting control points. Most skeleton-based methods are no better, again due to the small number of manually adjusted control points. In this paper, we propose a method to deform a generalized cylinder based on its skeleton composed of a centerline and orthogonal cross sections. Although we are not the first to use such a skeleton, we propose a novel skeletonization method that tries to minimize the number of intersections between neighboring cross sections by means of a relative curvature condition to detect intersections. The mesh deformation is first defined geometrically by deforming the centerline and mapping the cross sections. Rotation minimizing frames are used during mapping to control twisting. Secondly, given displacements on the cross sections, the deformation is decomposed into finely subdivided regions. We limit distortion at these vertices by minimizing an elastic thin shell bending energy,in linear time. Our method can handle complicated generalized cylinders such as the human colon.