巴基斯坦谢胡普拉农业区优先流三维结构及其影响因素

优先流是水通过土壤中特定路径的运动,而不是水在土壤结构里均匀地流动。由于土壤的异质性,例如裂缝、根通道或虫洞,这些优先流动路径经常形成。这种分形图案使理解和描述首选流动路线的行为变得具有挑战性。为了准确地进行水和溶质的输送,需要花费大量时间来理解和描述优先流路的增长和演变。传统模型需要改进来捕捉优先流的复杂和非线性行为。选取4块120 cm×120 cm样地,对4块样地进行染料示踪实验,以确认溶质和水的优选流动模式。数据已在Origin Lab中进行分析,以创建3D图表,并使用Sketchu p-2021 Pro向每个绘图提供0.50 L亮蓝溶液(5 g/L)。每个地块包含3个垂直的土壤剖面,每个剖面深150 cm,并且剖面墙经过广泛的刀具准备。将亮蓝留在表面24 h以渗透到土壤表面。结果表明:优先流在压实度最小且大孔隙连续性保持的区域最为突出。相反,压实的影响导致压实区域微孔隙率降低和优先流动模式减弱。亮蓝色在土壤中的最大深度可达15.5 cm。FCP的运动取决于不同的因素,如根部、毛孔、裂缝等。亮蓝色在根部可用的地方达到最大深度。在本研究中,通过使用Sketch Pro软件以三维方式显示亮蓝色运动,以便更好地理解它。此外,本研究揭示压实和随后的恢复过程如何影响土壤对水流和地表径流的敏感性。全面的3D表示,这项研究提供了对水流通道的形成和演化的深入理解。根据本研究发现的水流模式,在没有压实作用的较高位置,大孔隙连续性得以保留,择流最强。由于压实作用,微孔隙度下降,且越下侧越弱。该研究可以更好地理解水流通道的创建和演化。该研究增强对优先流及其在自然和农业生态系统中养分和水循环中的作用的了解。从这项研究中获得的见解可以为制定改进的农业用地管理策略提供信息,促进可持续和高效的水资源管理。

聚多巴胺固定的聚(2-甲基-2-噁唑啉)/聚(4-乙烯吡啶)混合刷对胃蛋白酶的可控吸附

在聚多巴胺修饰的基底表面同时接枝端基为氨基的聚(2-甲基-2-噁唑啉)和端基为巯基的聚(4-乙烯吡啶),制备了聚(2-甲基-2-噁唑啉)/聚(4-乙烯吡啶)混合刷.通过X射线光电子能谱、可变角光谱型椭偏仪、zeta电位仪和静态水接触角对涂层进行表征.结果表明,混合刷的组成可以通过改变聚(2-甲基-2-噁唑啉)和聚(4-乙烯吡啶)的投料比控制.此外,改变环境pH值和混合刷组成比例可以调节混合刷涂层表面的zeta电位和水接触角.采用异硫氰酸荧光素标记胃蛋白酶.和表面等离子体共振研究了胃蛋白酶在聚(2-甲基-2-噁唑啉)/聚(4-乙烯吡啶)混合刷表面的响应性吸附/脱附能力结果表明,通过调整聚(2-甲基-2-噁唑啉)或聚(4-乙烯吡啶)的组分比,在pH=3时,聚(2-甲基-2-噁唑啉)/聚(4-乙烯吡啶)混合刷表面可以吸附大量的胃蛋白酶;在pH=7时,脱附效率达到92%以上.

基于聚(2-甲基-2-[口恶]唑啉)和聚丙烯酸的混合刷在毛细管电泳在线富集溶菌酶中的应用

制备了一种对溶菌酶具有可控吸附性能的混合刷涂层毛细管,用于毛细管电泳在线富集溶菌酶以提高其检测灵敏度。首先,分别通过阳离子开环聚合和可逆加成-断裂链转移(RAFT)聚合合成聚(2-甲基-2-[口恶]唑啉)(PMOXA)和聚丙烯酸(PAA),然后将甲基丙烯酸缩水甘油酯(GMA)分别与PMOXA和PAA通过自由基共聚和RAFT聚合合成出聚(2-甲基-2-[口恶]唑啉)-r-甲基丙烯酸缩水甘油酯(PMOXA-r-GMA)和聚丙烯酸-b-聚甲基丙烯酸缩水甘油酯(PAA-b-PGMA)。将PMOXA-r-GMA和PAA-b-PGMA的混合溶液以一定比例加入到毛细管内,通过加热即可制备出基于PMOXA和PAA的混合刷涂层毛细管。X射线光电子能谱(XPS)对毛细管原材料的表面组成研究结果表明,当混合溶液质量浓度为20 g/L、PMOXA-r-GMA和PAA-b-PGMA质量比为1∶1时,所得涂层中羧基的含量随着PAA链长的增加而增加;异硫氰酸荧光素标记溶菌酶(FITC-溶菌酶)吸附实验结果显示,通过改变环境的pH和离子强度(I)可以调控涂层毛细管对溶菌酶的吸附和释放,在pH 7(I=10^-5mol/L)条件下,毛细管可以吸附大量的溶菌酶,当条件变为pH 3(I=10^-1mol/L)时,吸附的溶菌酶可以被释放出来。将这种具有溶菌酶可控吸附性能的涂层毛细管用于毛细管电泳在线富集溶菌酶,当PAA链长是PMOXA链长的2.2倍时,溶菌酶的灵敏度增强因子为17.69,检出限为8.7×10^-5g/L;同一天内对溶菌酶连续测定5次以及连续测定5天,峰面积的日内、日间相对标准偏差(RSD)分别为2.9%和4.1%,迁移时间的日内、日间RSD分别为0.9%和2.1%。涂层的制备只需一步,简单易行,而且涂层具有很好的稳定性。本研究为毛细管电泳分析痕量蛋白质提供了一种简单有效的方法。

Enhanced Reversible Zinc Ion Intercalation in Deficient Ammonium Vanadate for High-Performance Aqueous Zinc-Ion Battery

Ammonium vanadate with bronze structure(NH_(4)V_(4)O_(10))is a promising cathode material for zinc-ion batteries due to its high specific capacity and low cost.However,the extraction of NH^(+)_(4) at a high voltage during charge/discharge processes leads to irreversible reaction and structure degradation.In this work,partial NH^(+)_(4) ions were pre-removed from NH_(4)V_(4)O_(10) through heat treatment;NH_(4)V_(4)O_(10) nanosheets were directly grown on carbon cloth through hydrothermal method.Defi-cient NH_(4)V_(4)O_(10)(denoted as NVO),with enlarged interlayer spacing,facilitated fast zinc ions transport and high storage capacity and ensured the highly reversible electrochemical reaction and the good stability of layered structure.The NVO nanosheets delivered a high specific capac-ity of 457 mAh g^(−1) at a current density of 100 mA g^(−1) and a capacity retention of 81%over 1000 cycles at 2 A g^(−1).The initial Coulombic efficiency of NVO could reach up to 97%compared to 85%of NH_(4)V_(4)O_(10) and maintain almost 100%during cycling,indicating the high reaction reversibility in NVO electrode.

聚合物涂层在毛细管电泳分离蛋白中的研究进展

毛细管电泳具有分析时间短,分离效率高,样品消耗量少等优点,在生物样品分离,特别是蛋白质分析领域有重要应用。然而,毛细管内壁硅羟基的解离给分离结果带来诸多不良影响。聚合物涂层能够抑制蛋白质在毛细管内壁的吸附以及调控电渗流,故对毛细管内壁进行有效修饰能够提高其对蛋白质的分离效率及分离稳定性。该文主要综述了动态及静态聚合物涂层毛细管的最新研究进展,并概述了近些年基于多巴胺/聚多巴胺发展起来的涂层毛细管的研究进展,最后展望了聚合物涂层毛细管的发展趋势。

Two novel variants in CYP1B1 gene: a major contributor of autosomal recessive primary congenital glaucoma with allelic heterogeneity in Pakistani patients

AIM: To find the CYP1 B1 mutations associated with primary congenital glaucoma(PCG) in Pakistani consanguineous pedigrees. METHODS: After getting informed consent, 11 consanguineous pedigrees belonging to different ethnic groups were enrolled. Detailed medical history was recorded and pedigrees were drawn. The standard ophthalmological examination was done to characterize the phenotype. Genomic DNA was extracted from 10 mL whole blood and coding exons and exon intron boundaries of CYP1 B1 gene were directly sequenced. Bioinformatics tools were used to model the mutant protein and predict the effect of novel variants on protein structure and function. RESULTS: Sequencing analysis revealed 5 different CYP1 B1 variants in 7 families(7/11; 64%), including two novel variants. A common mutation, p.R390 H was found in four families, whereas p.P437 L was found once in a family. Two novel variants, a homozygous non sense variant p.L13* and a compound heterozygous variant, p.P350 T along with p.V364 M were segregating with PCGin two families. All the patients had the variable onset and severity of the disease. The success rate of early clinical interventions was observed dependent on mutation types and position. Two different haplotypes were associated with frequently found mutation, p.R390 H. CONCLUSION: Identification of novel CYP1 B1 variants reassert the genetic heterogeneity of Pakistani PCG patients. The patients with missense mutations show severe phenotypic presentations and poor vision after surgical interventions as compare to patients with null variants. This may help to better understand the role of CYP1 B1 mutations in the development of PCG and its course of pathogenicity.

From Molecular Pathology of COVID-19 to Nigella Sativum as a Treatment Option:Scientific Based Evidence of Its Myth or Reality

COVID-19 virus is a causative agent of viral pandemic in human beings which specifically targets respiratory system of humans and causes viral pneumonia.This unusual viral pneumonia is rapidly spreading to all parts of the world,currently affecting about 105 million people with 2.3 million deaths.Current review described history,genomic characteristics,replication,and pathogenesis of COVID-19 with special emphasis on Nigella sativum(N.sativum)as a treatment option.N.sativum seeds are historically and religiously used over the centuries,both for prevention and treatment of different diseases.This review summarizes the potential role of N.sativum seeds against COVID-19 infection at levels of in silico,cell lines and animal models.

A block-based secure and robust watermarking scheme for color images based on multi-resolution decomposition and de-correlation

This paper presents a block-based secure and robust watermarking technique for color images based on multi-resolution decomposition and de-correlation.The principal objective of the presented scheme is to simultaneously meet all the four requirements(robustness,security,imperceptibility,and capacity)of a good watermarking scheme.The contribution of this study is to basically achieve the four contradictory requirements that a good watermarking scheme must meet.To do so,different approaches are combined in a way that the four requirements are achieved.For instance,to obtain imperceptibility,the three color channels(red,green,and blue)are de-correlated using principal component analysis,and the first principal component(de-correlated red channel)is chosen for watermark embedding.Afterwards,to achieve robustness,the de-correlated channel is decomposed using a discrete wavelet transform(DWT),and the approximate band(the other three bands are kept intact to preserve the edge information)is further decomposed into distinct blocks.The random blocks are chosen based on a random generated key.The random selected blocks are further broken down into singular values and vectors.Based on the mutual dependency on singular values and vectors’matrices,the values are modified depending on the watermarking bits,and their locations are saved and used as another key,required when the watermark is to be extracted.Consequently,two-level authentication levels ensure the security,and using both singular values and vectors increases the capacity of the presented scheme.Moreover,the involvement of both left and right singular vectors along with singular values in the watermarking embedding process strengthens the robustness of the proposed scheme.Finally,to compare the presented scheme with the state-of-the-art schemes in terms of imperceptibility(peak signal-to-noise ratio and structural similarity index),security(with numerous fake keys),robustness(normalized correlation and bit error rate),and capacity,the Gonzalez and Kodak datasets are used.The comparison shows significant improvement of the proposed scheme over existing schemes.

Reversible Protein Adsorption on PMOXA/PAA Based Coatings:Role of PAA

In this study we report design of stimuli-resP0nsive coating based on poly（2-methyl-2-oxazoline-random-glycidyl methacrylate） （PMOXA-r-GMA） comb copolymer and poly（acrylic acid）-block-poly（glycidyl methacrylate） （PAA-b-PGMA） block copolymers and scrutinize its ability to control protein adsorption. Firstly, PMOXA/PAA based coatings were prepared by simply spin coating the mixture of PMOXA-r-GMA and PAA-b-PGMA copolymer solutions onto silicon substrates followed by annealing at 110℃. Then coatings were rigorously characterized by X-ray photoelectron spectroscopy （XPS）, the static water contact angle （WCA） test, ellipsometry and atomic force microscopy （AFM）. After that, the relationship of switchable behavior of PMOXA/PAA based coatings with PAA content and chain length was investigated through the change of thickness and WCA upon pH and ionic strength （I） trigger, which indicated that the change in thickness and WCA was triggered when PAA contents were increased as well as by increasing chain length of PAA in PMOXA/PAA based coatings. Finally, real-time adsorption/desorption of lysozyme （Lyso） on PMOXA/PAA based coatings was monitored using quartz crystal microbalance with dissipation monitoring （QCM-D）. The results showed that the Lyso adsorption amount was increased upon increasing chain length and contents of PAA in PMOXA/PAA based coatings. The adsorbed Lyso was then efficiently desorbed by changing pH and I of medium with the maximum desorption （〉 90% desorption percentage） observed for the suitable ratio of PMOXA and PAA while chain length of PAA was kept longer than that of PMOXA. Furthermore, the prepared coatings were found to repeatedly adsorb and desorb Lyso for four successive cycles of adsorption/desorption, which confirmed the stability of prepared coatings.