Frontal affinity chromatography: A unique research tool for biospecific interaction that promotes glycobiology

Combination of bioaffinity and chromatography gave birth to affinity chromatography. A further combination with frontal analysis resulted in creation of frontal affinity chromatography (FAC). This new versatile research tool enabled detailed analysis of weak interactions that play essential roles in living systems, especially those between complex saccharides and saccharide-binding proteins. FAC now becomes the best method for the investigation of saccharide-binding proteins (lectins) from viewpoints of sensitivity, accuracy, and efficiency, and is contributing greatly to the development of glycobiology. It opened a door leading to deeper understanding of the significance of saccharide recognition in life. The theory is also concisely described.     

Shear strength at Sisal fibre–polyester resin interfaces: use of inverse gas chromatography to study pretreatment effects

Inverse gas chromatography, IGC, has been used to investigate changes to the surface of Sisal fibres on treatment with sodium hydroxide. By determining the retention of a series of alkane probes and of probes with acidic or basic character, it was shown that little change to the chemical nature of the surface occurs as measured by the enthalpy of adsorption of alkane probes or the dispersion component of the surface free energy. This IGC study supports the conclusion of previous work involving S.E.M. which suggested that the major effect of the treatment was the removal of weak or adventitious layers from the substrate surface, thus increasing the interfacial shear strength when incorporated into polyester resin.     

Determination of arsenic species in mainstream cigarette smoke based on inductively coupled plasma mass spectrometry

In this work, arsenic species in mainstream cigarette smoke condensates was systemically studied with inductively coupled plasma mass spectrometry. A single particle inductively coupled plasma mass spectrometry was utilized for analysis of the physical forms of arsenic, and no particle arsenic was observed in mainstream cigarette smoke condensates. The solvent extraction experiments proved that the water-soluble arsenic was the main species in mainstream cigarette smoke condensates, which was consistent with the result of single particle inductively coupled plasma mass spectrometry. Furthermore, speciation of arsenite, arsenate, monomethylarsonic acid, and dimethylarsinic acid was investigated using high performance weak anion exchange chromatography coupled with inductively coupled plasma mass spectrometry detection. The developed high performance liquid chromatography coupled inductively coupled plasma mass spectrometry method was successfully applied to the determination of arsenic species in mainstream cigarette smoke condensates with satisfactory recoveries. Four arsenic species were detected in the mainstream cigarette smoke condensates from four brands of commercial available cigarettes, and there was a great difference between the arsenic content and composition among the different brands of cigarettes. It is found that arsenate was the main species in all tested cigarette samples.     

Efficiency and resistance of the artificial oxalate protection treatment on marble against chemical weathering

The artificial oxalate protection method was analyzed in laboratory experiments in order to achieve an optimum treatment application and concentration giving rise to its most effective protective nature. Spectroscopic (Fourier transform infrared, Micro-Raman and UV-vis colorimetry), microscopic (scanning electron microscope) and contact-angle analyses were carried out to characterize Carrara marble samples before and after application of the treatment to validate its efficiency. The resistance effects against chemical weathering were subsequently observed in a lab-controlled weak acid rain experiment. An acid spray at pH 5.5, representative of normal rain was used to provoke degrade of natural marble, marble treated with the artificial oxalate protective at concentrations of 0.4 and 5% and marble treated with a commercial organic silicon product. Run-off solutions sampled at timely intervals were tested for any change in pH followed by ion chromatography measurements for the presence of calcium ions in solution. The chromatography results of the oxalate treatment applied at a 5% concentration are analogous to an organic commercial product indicating its validity as a method for the conservation of carbonate substrates conferring protection to stone materials against acid environments.     

大鼠肾脏糖胺聚糖的种类及二糖组成分析

采用两步酶解和离子交换色谱从Wistar大鼠肾脏中提取糖胺聚糖,以醋酸纤维素薄膜电泳分析糖胺聚糖种类,以弱阴离子交换色谱分离各种糖胺聚糖.纯化后的糖胺聚糖分别经特定糖胺聚糖酶裂解,采用强阴离子交换高效液相色谱(SAX-HPLC)紫外检测分析其二糖组成.结果表明,Wistar大鼠肾脏糖胺聚糖主要由硫酸乙酰肝素和少量硫酸皮肤素组成.硫酸乙酰肝素含有8种二糖,其中含有乙酰基二糖总含量高达77.6%,非硫酸化二糖(Ⅳ-A)含量为59.7%;硫酸皮肤素含有6种二糖,其中单硫酸化二糖总含量为54.8%,非硫酸化二糖含量为32.9%.     

鸦胆子油中各基团积分值的估算

鸦胆子油在治疗颈癌、胃癌、肺癌等方面,已取得较好的疗效^[1,2]。本文用¹H NMR测定了该油的各组峰面积积分。为纠正最强峰C CH₂C对其两侧弱峰的干扰,作者提出一个经验公式以扣除基团重叠部分的积分值。并按文献[3]的方法,计算了鸦胆子油中每摩尔所含各功能团的个数、各功能团间的比率、酯化度、不饱和度、结合脂肪酸基平均碳数和平均分子量等。并从所测得结合脂肪酸的含量,估算出鸦胆子油中的油酸的含量,结果与文献[4]相符。     

水体多环芳烃组分识别小样本分析方法研究

多环芳烃(PAHs)是一类在自然环境中常见且广泛存在的有毒有害有机物。其主要来源有自然界的各种微生物以及植物的生物合成，富含植被区域的天然火灾，火山的喷发物，化石燃料以及人为工业碳氢化合物的不完全燃烧和运输过程中的石油泄漏等。多环芳烃的毒性较为强烈，具有生物致癌性，遗产毒性和致突变性。它对于人体呼吸系统，循环系统，神经系统有着多方面的危害，是一种重要的有机污染物，因此有必要对多环芳烃的现场监测和分析方法进行研究。目前对于多环芳烃的分析方法主要有化学分析法和光谱分析法。化学分析法包含有前处理的化学滴定法，液相色谱法(LC)，高效液相色谱法(HPLC)，气相色谱质谱法（GC-MS）；光谱学分析法涉及紫外吸收光谱，荧光光谱和三维荧光光谱等。三维荧光光谱同时获得激发波长和发射波长的信息，因而包含的光学信息十分丰富，灵敏度高，光谱特征显著，在实际水体的现场检测和水体样本混合组分的快速研究有明显的优势。常见的三维荧光光谱解析方法有平行因子分析法(PARAFAC)，多维偏最小二乘法(N-PLS)等。平行因子分析是分析多环芳烃重叠三维荧光光谱的一种有效方法。但有时由于多种组分的荧光较弱，它对三维荧光光谱的欠定分析并不能得到令人满意的结果。为了从两个样品中提取更多的成分，提出一种基于奇异值分解(SVD)和PARAFAC的方法。首先对每个观测样本进行奇异值分解，根据累积贡献率选取合适的奇异值，构造新的伪样本来突出微弱的荧光信号。然后，将两个观测样品及其对应的伪样品输入PARAFAC，恢复组分光谱。为验证所提方法的有效性，对三组不同荧光强度的多环芳烃重叠三维荧光光谱进行了分析。结果表明，从两个混合样品中提取并识别出6个多环芳烃的纯组分光谱，其分辨发射和激发光谱与标准光谱的相似性均在0.80以上。     

Adsorption Properties of β‐Cyclodextrin for Adsorbing Aromatic Hydrocarbons from the Gas Phase and Water

β‐cyclodextrin (β‐CD) is a potentially useful adsorbent for the adsorption of aromatic hydrocarbons from the gas phase and water. In this paper, the adsorption properties of β‐CD for adsorbing six aromatic hydrocarbons from the gas phase and seven aromatic hydrocarbons from water were measured. The inverse gas chromatography (IGC) technique was used to characterize the Flory interaction parameters of β‐CD and the six aromatic hydrocarbons from the gas phase at 40, 50, 60, and 70°C. For these aromatic hydrocarbons, the order of β‐CD adsorption ability from strong to weak was: styrene>ethylbenzene>o‐xylene>chlorobenzene>toluene>benzene. For the seven aromatic hydrocarbons in water, adsorption values α, were measured at 20, 30, 40, and 50°C. The order of β‐CD adsorption ability from strong to weak was: ethylbenzene>o‐xylene>styrene>chlorobenzene>toluene>benzene>phenol. This trend was explained based on their solubility degrees in water. It was found that the adsorption abilities of β‐CD for adsorbing aromatic hydrocarbons from the gas phase and water have a similar trend.     

麻黄生物碱中一对光学异构体在薄层色谱原位的表面增强拉曼光谱研究

应用表面增强技术(SERS)将薄层色谱(TLC)与傅里叶变换拉曼光谱(FT-Raman)联用,在薄层色谱分离斑点原位,获得中草药麻黄中麻黄生物碱衍生物中一对关于手性碳的光学异构体：去甲基麻黄碱,去甲基伪麻黄碱指纹光谱的新方法。研究表明,在薄层色谱原位仅16 μg的样品,就可获得以上分子的主要特征谱带;并且光学异构体的光谱特征明显不同,在银溶胶微粒表面增强作用下去甲基麻黄碱、去甲基伪麻黄碱分子中与苯环相关的波数为1 004,1 605 cm-1振动获最大增强。从而阐明了应用TLC-SERS联用技术,可有效地对中草药主要化学成分中光学异构体进行高灵敏度分离与指纹鉴定。     

Weak Commutative Pseudoeffect Algebras

As noncommutative generalizations of effect algebras, we introduce weak commutative pseudoeffect algebras. In this paper, we prove that the generalized pseudoeffect algebras can be unitized if and only if they are weak commutative. Then we discuss the relationships between weak commutative pseudoeffect algebras and weak commutative generalized pseudoeffect algebras. We prove that the category of weak commutative pseudoeffect algebras is a reflective subcategory of weak commutative generalized pseudoeffect algebras. Similarly, we introduce weak commutative pseudodifference posets and show the relationships between weak commutative pseudoeffect algebras and weak commutative pseudodifference posets.     

New approach in synthesis,characterization and release study of pH-sensitive polymeric micelles,based on PLA-Lys-<Emphasis Type="Italic">b</Emphasis>-PEGm,conjugated with doxorubicin

Amphiphilic block copolymers are well established as building blocks for the preparation of micellar drug carriers. The functional polymer micelles possess several advantages, such as high drug efficiency, targeted delivery, and minimized cytotoxicity. The synthesis of block copolymers using nano-structured templates has emerged as a useful and versatile approach for preparing drug carriers. Here, we report the synthesis of a smart polymeric compound of a diblock PLA-Lys-b-PEG copolymer containing doxorubicin. We have synthesized functionalized diblock copolymers, with lysinol, poly(lactide) and monomethoxy poly(ethylene glycol) via thermal ring-opening polymerization and a subsequent six-step substitution reaction. A variety of spectroscopic methods were employed here to verify the product of our synthesis. ¹H-Nuclear magnetic resonance and Fourier transform infrared studies validated the expected synthesis of copolymers. Doxorubicin is chemically loaded into micelles, and the ex vitro release can be evaluated either in weak acidic or in SBF solution by UV–vis spectroscopy. Dynamic light scattering, thermo gravimetric analysis, and size exclusion chromatography have also been used.     

Weak Observables in MV Algebras

A notion of a weak observable is defined and aconstruction of a weak observable is examined. With thehelp of the construction, the sum of weak observables isrealized as well as the upper and lower limits of a sequence of weak observables.     

强非局域非线性介质中强光导引的弱光呼吸子传输规律研究

研究了强光导引的弱光呼吸子传输问题. 尽管弱光本身的非线性效应可以忽略, 但强光通过强非局域非线性效应会对弱光形成约束并与弱光本身的衍射效应达到动态平衡, 从而形成呼吸子. 得到了弱光呼吸子的解析表达式, 在此基础上分析了其束宽的呼吸演化规律, 并对弱光呼吸子整体轨迹的形状、方位、旋向等性质进行了系统的研究.     

Weak values and the Leggett-Garg inequality in solid-state qubits

An implementation of weak values is investigated in solid-state qubits. We demonstrate that a weak value can be nonclassical if and only if a Leggett-Garg inequality can also be violated. Generalized weak values are described in which post-selection occurs on a range of weak measurement results. Imposing classical weak values permits the derivation of Leggett-Garg inequalities for bounded operators. Our analysis is presented in terms of kicked quantum nondemolition measurements on a quantum double-dot charge qubit.     

Weak measurements with arbitrary probe states

The exact conditions on valid probe states for weak measurements are derived. It is demonstrated that weak measurements can be performed with any probe state with vanishing probability current density. This condition is found both for weak measurements of noncommuting observables and for c-number observables. In addition, the interaction between object and probe must be sufficiently weak. Strange weak values can be observed also with mixed probe states, but not for c-number observables.     

基于随机共振进行弱信号探测的实验研究

非线性随机共振系统可利用噪声增强微弱信号检测的能力,为强噪声背景下微弱信号的检测开创了新方法.基于随机共振的基本原理设计了硬件电路系统,并将其应用于检测单频和多频微弱信号;通过输入模拟工程实际的带噪信号,采样所得的输出信号的频谱分析结果表明,利用随机共振技术可从强噪声背景下有效地提取出单频和多频弱信号.多频弱信号的有效提取拓展了基于随机共振原理的弱信号检测技术的应用领域,结合数字滤波处理技术有效地消除了低频噪声对信号识别的影响.基于随机共振的弱信号检测技术在信息识别与信息处理方面具有巨大的潜在的应用价值.     

The three-nucleon problems with weak NN interaction

We consider the three-nucleon system in which each two-nucleon pair interacts both strongly and weakly. The strong part is assumed to be separable but an addition of small non-separable term is possible. The weak two-nucleon interaction (which is absolutely non-separable) is assumed to be given in terms of its partial wave components in momentum space. These elements have been calculated by Lassey and McKellar starting from recent models of non-relativistic (strangeness conserving non-leotonic) NN weak interaction. An expression for the weak part of the elastic nucleon-deuteron scattering amplitude is derived within the framework of two potential scattering theory. The weak three-body driving terms are explicitly evaluated. They reflect weak form factors responsible for the weak dissociation of two nucleon isobars (including parity impurity of the deuteron wave function) as well as weak NN scattering. The expressions appearing below are numerically tractable and can be used to elaborate on previous calculations.     

Electromagnetically induced grating in a four-level tripod-type atomic system

An electromagnetically induced grating in a four-level tripod-type atomic system is studied theoretically. By virtue of a weak standing-wave signal field, the phase modulation effectively diffracts a weak probe field into the first-order direction. By changing the weak signal field, the diffraction of the weak probe field can be modulated in real time, and a first-order diffraction efficiency of more than 32% can be obtained with proper parameters. Such a system has a potential application in an all-optical switch controlled by a weak optical signal.     

Interpreting weak value amplification with a toy realist model

Constructing an ontology for quantum theory is challenging, in part due to measurement back-action. The Aharonov-Albert-Vaidman weak measurement formalism provides a method to predict measurement results (weak values) when back-action is negligible. The weak value appears analogous to a classical conditional mean, yet can be complex and unbounded. We study weak values in the context of a recent quantum optical experiment involving two-photon interactions. The results of the experiment are reinterpreted within a realist ‘stochastic optics’ model of light. We show that the conditional means of the intensities in the model correspond to the experimentally observed weak values and study the breakdown of the model outside the experimentally probed regime in the limit where the weak value predicts ‘anomalous’ results.     

Neuronal oscillators in aplysia californica that demonstrate weak coupling in vitro

Networks of oscillators produce vital activity in diverse natural systems. The dynamics of these networks are frequently studied via computational models that assume weak coupling, yet this assumption has not been experimentally validated. We applied weak stimuli to neuronal oscillators in Aplysia californica and deconvolved infinitesimal phase response curves (IPRCs) that describe the phase response of a neuron. We show that these IPRCs reliably predict the phase response for weak stimuli, independent of the stimulus waveform used. These weak stimuli are in the range of normal synaptic activity for these neurons, suggesting that weak coupling is a likely mechanism.