Developing an atmospheric aging evaluation model of acrylic coatings:A semi-supervised machine learning algorithm

To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in China.An atmospheric aging evaluation model of acrylic coatings was developed based on aging data including11 environmental factors from 567 cities.A hybrid method of random forest and Spearman correlation analysis was used to reduce the redundancy and multicollinearity of the data set by dimensionality reduction.A semi-supervised collaborative trained regression model was developed with the environmental factors as input and the low-frequency impedance modulus values of the electrochemical impedance spectra of acrylic coatings in 3.5wt%NaCl solution as output.The model improves accuracy compared to supervised learning algorithms model(support vector machines model).The model provides a new method for the rapid evaluation of the aging performance of acrylic coatings,and may also serve as a reference to evaluate the aging performance of other organic coatings.

Macrophage-derived SHP-2 inhibits the metastasis of colorectal cancer via Tie2-PI3K signals

This research aimed to explore the influence of Src homology-2 containing protein tyrosine phosphatase(SHP-2)on the functions of tyrosine kinase receptors with immunoglobulin and EGF homology domains 2(Tie2)-expressing monocyte/macrophages(TEMs)and the influence of the angiopoietin(Ang)/Tie2-phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)(Ang/Tie2-PI3K/Akt/mTOR)signaling pathway on the tumor microvascular remodeling in an immunosuppressive microenvironment.In vivo,SHP-2-deficient mice were used to construct colorectal cancer(CRC)liver metastasis models.SHP-2-deficient mice had significantly more metastatic cancer and inhibited nodules on the liver surface than wild-type mice,and the high-level expression of p-Tie2 was found in the liver tissue of the macrophages’specific SHP-2-deficient mice(SHP-2MACKO)+planted tumor mice.Compared with the SHP-2 wild type mice(SHP-2WT)+planted tumor group,the SHP-2MAC-KO+planted tumor group experienced increased expression of p-Tie2,p-PI3K,p-Akt,p-mTOR,vascular endothelial growth factor(VEGF),cyclooxygenase-2(COX-2),matrix metalloproteinase 2(MMP2),and MMP9 in the liver tissue.TEMs selected by in vitro experiments were co-cultured with remodeling endothelial cells and tumor cells as carriers.It was found that when Angpt1/2 was used for stimulation,the SHP-2MAC-KO+Angpt1/2 group displayed evident increases in the expression of the Ang/Tie2-PI3K/Akt/mTOR pathway.The number of cells passing through the lower chamber and the basement membrane and the number of blood vessels formed by cells compared with the SHP-2WT+Angpt1/2 group,while these indexes were subjected to no changes under the simultaneous stimulation of Angpt1/2+Neamine.To sum up,the conditional knockout of SHP-2 can activate the Ang/Tie2-PI3K/Akt/mTOR pathway in TEMs,thereby strengthening tumor micro angiogenesis in the microenvironment and facilitating CRC liver metastasis.

Enhanced and irreversible sorption of pesticide pyrimethanil by soil amended with biochars

Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants. Biochars were prepared by burning of red gum （Eucalyptus spp.） woodchips at 450 and 850℃ （labeled as BC450 and BC850）. These two biochars were found to possess markedly different properties in terms of surface area and porosity. Short-term equilibration tests （24 hr） were conducted to assess the sorption-desorption behavior of pyrimethanil in the soil amended with various amounts of biochar of each type, with a special focus on the desorption behavior of the sorbed pesticide through four times successive desorption by dilution. Sorption coefficient and isotherm nonlinearity of the amended soils progressively increased with the content of biochar in the soil. Biochar BC850 with higher surface area and microporosity showed a stronger effect on the reversibility of sorption pesticide. The soils amended with 5% BC450 and 1% BC850 had nearly the same sorption capacity for pyrimethanil; however, their desorption processes were very different with 13.65% and 1.49% of the sorbed pesticide being released, respectively. This study suggested that biochar in soil could be an important factor for immobilization of a pesticide and thus affecting its environment fate in soil.

第一代EGFR酪氨酸激酶抑制剂治疗106例复合EGFR突变肺癌患者:一项单中心临床研究

背景与目的酪氨酸激酶抑制剂(tyrosine kinase inhibitors,TKIs)对具有复合表皮生长因子受体(epidermal growth factor receptor,EGFR)突变的肺癌患者的疗效尚不确切。我们对第一代TKI治疗存在复合EGFR突变肺癌患者的疗效进行了单中心研究。方法2012年1月至2016年5月共确诊106例存在复合EGFR突变的连续肿瘤患者,所有患者均接受第一代TKI治疗。外显子19缺失和外显子21的L858R点突变为常见突变;由于T790M与TKIs耐药性相关,因此单独考虑T790M;其他突变均被定义为罕见突变。患者分组如下:双重常见突变(A组),常见加T790M突变(B组),常见加罕见突变(C组),双重罕见突变(D组)和罕见加T790M突变(E组)。我们建立了一个单独的组(F组),由115例存在单一常见突变的连续患者组成,以进行比较分析。结果EGFR复合突变患者的发生率为2.9%(114/3925),对第一代TKI的反应率为50.9%,与F组相比无显著性差异(67.0%,P=0.088)。接受TKI治疗的106例患者的无进展生存期(progression-free survival,PFS)比F组短(中位数,9.1个月vs.13.0个月,P<0.001)。复合突变组的PFS短于单一常见突变组(中位数,A组10.1个月,P=0.240;B组9.1个月,P<0.001;C组9.6个月,P=0.010;D组6.5个月,P=0.048;E组5.4个月,P=0.017)。外显子20中(不包括T790M)发生共同突变的患者显示出比其他复合突变或单一常见突变患者更短的PFS,差异具有统计学意义(中位数,6.5个月vs.9.1个月vs.13.0个月,P=0.002)。结论复合EGFR突变及其对第一代TKIs的反应存在显著的异质性。在临床中对每位患者都应考虑进行个体化治疗。

Two aquaporins,PIP1;1 and PIP2;1,mediate the uptake of neonicotinoid pesticides in plants

Neonicotinoids(NEOs),a large class of organic compounds,are a type of commonly used pesticide for crop protection.Their uptake and accumulation in plants are prerequisites for their intra-and intercellular move-ments,transformation,and function.Understanding the molecular mechanisms that underpin NEO uptake by plants is crucial for effective application,which remains elusive.Here,we demonstrate that NEOs enter plant cells primarily through the transmembrane symplastic pathway and accumulate mainly in the cytosol.Two plasma membrane intrinsic proteins discovered in Brassica rapa,BraPIP1;1 and BraPIP2;1,were found to encode aquaporins(AQPs)that are highly permeable to NEOs in different plant species and facilitate NEO subcellular diffusion and accumulation.Their conserved transport function was further demonstrated in Xenopus laevis oocyte and yeast assays.BraPIP1;1 and BraPIP2;1 gene knockouts and interaction as-says suggested that their proteins can form functional heterotetramers.Assessment of the potential of mean force indicated a negative correlation between NEO uptake and the energy barrier of BraPIP1;1 chan-nels.This study shows that AQPs transport organic compounds with greater osmolarity than previously thought,providing new insight into the molecular mechanisms of organic compound uptake and facilitating innovations in systemic pesticides.

猪关节软骨三层力-电特性的实验研究

力-电特性是关节软骨中众所周知的特性之一.然而目前还不清楚软骨组织不同区域的力-电特性.因此,本文的目的是研究关节软骨各区域的力-电特性及其相关影响因素.施加载荷后,力-电特性产生的电压信号沿软骨厚度方向由浅表层向深层逐渐增加,并且这种机制只有在应力产生明显相对变化时才能表现出来.此外,关节软骨的力-电特性产生的电压信号会随着载荷峰值和加载速率的增加而明显增加.我们通过将实验结果与指数函数进行拟合,得出了软骨各区的力-电特性的电压变化规律.研究结果表明,软骨组织不同区域的力-电特性差异在很大程度上取决于胶原纤维的排列分布.另外,软骨的内部结构和外部加载条件对关节软骨的力-电特性也有重要影响.这可为组织工程学中人工植入压电材料治疗骨关节炎提供重要参考.

可定制多孔玻璃表面的溶解制造策略

玻璃表面微纳结构的设计和制造在实现所需功能方面具有重要意义.然而,玻璃固有的硬度和脆性给传统制造方法带来了不便.因此,开发一种简单且可控的制造策略对于制备具备功能应用的微纳结构玻璃至关重要.在本文中,我们提出了一种创新方法,利用可溶性氯化钠颗粒作为前驱体模板,在玻璃表面上创建可定制的多孔结构.通过我们的先导成型策略,成功利用可溶性氯化钠颗粒的潜力作为前驱体模板,从而便于制造量身定制的多孔玻璃表面.通过调节这些颗粒的大小和组合,我们实现了对所得多孔玻璃的连续调控,范围从超亲水(1°)到超疏水(142°).值得注意的是,制备的多孔玻璃表面表现出显著的亲油性,展示了在油水分离和自清洁等多种应用方面的巨大潜力.最重要的是,即使经过了10次制造迭代,玻璃表面的疏水-亲油功能依然完好,凸显了我们策略的耐久性和可重复性.这种方法为实现玻璃的特殊功能提供了方便且具有成本效益的途径,为不同领域的进展铺平了道路.

First-generation EGFR tyrosine kinase inhibitor therapy in 106 patients with compound EGFR-mutated lung cancer: a single institution’s clinical practice experience

Background:The antitumour efficacy of tyrosine kinase inhibitors(TKIs)in lung cancer patients with compound epidermal growth factor receptor(EGFR)mutations has not been resolved.Our study summarizes a single institutional experience of first-generation TKI therapy for lung cancers with compound EGFR mutations.Methods:A total of 106 consecutive patients with tumours bearing compound EGFR mutations were identified between January 2012 and May 2016;all patients received first-generation TKI therapy.Deletions in exon 19 and the L858R point mutation in exon 21 were considered common mutations;T790M was considered separately because of its association with TKIs resistances.Any other mutation was defined as a rare mutation.Patients were divided as follows:double common mutations(group A);common plus T790M mutations(group B);common plus rare muta-tions(group C);double rare mutations(group D);and rare plus T790M mutations(group E).A separate group of 115 consecutive patients with a single common mutation was created for comparative analysis(group F).Results:The frequency of patients with compound EGFR was 2.9%(114/3925)and their response rate to first-genera-tion TKIs was 50.9%,which was not significantly different from group F(67.0%,P=0.088).The progression-free survival(PFS)of the 106 patients receiving TKI therapy was worse than that of group F(median,9.1 vs.13.0 months,respec-tively;P<0.001).The PFS of the compound mutation group was shorter than that of the single common mutation group(median,10.1 months in group A,P=0.240;9.1 months in group B,P<0.001;9.6 months in group C,P=0.010;6.5 months in group D,P=0.048;5.4 months in group E,P=0.017).Patients with a co-occurring mutation in exon 20(excluding T790M)exhibited significantly worse PFS than the patients with other compound mutations or with a single common mutation(median,6.5 vs.9.1 vs.13.0 months,respectively,P=0.002).Conclusions:There was significant heterogeneity among the compound EGFR mutations and their response to first-generation TKIs.Individualized treatment in clinical practice should be considered for each case.

Metalens-based stereoscopic microscope

Stereoscopic microscopy is a promising technology to obtain three-dimensional microscopic images.Such microscopes are based on the parallax effect,and as such require two lenses to focus at two different points.Geometrical constraints,however,restrict their numerical apertures to about 0.2,thus limiting the system’s resolution.Higher numerical apertures(.35)can be achieved with designs using only one bulk lens,but such systems are0 times more costly than the conventional ones.Thus,there is a pressing need for alternative solutions to improve the resolution of stereoscopic systems.Here,we show that high-resolution and low-cost stereoscopic systems can be obtained using birefringent single-layer metalenses.We design and fabricate a birefringent metalens operating at 532 nm with a numerical aperture as high as 0.4.The metalens is then used to demonstrate high-resolution stereoscopic imaging of biological samples.The microscopic images are further displayed and perceived vividly in an autostereoscopic display.Our demonstration paves the way to a new strategy to achieve high-resolution and low-cost stereoscopic microscopes.