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It is difficult to determine the effective length coefficient of weakly braced frame columns using the effective length coefficient method. When the stability of braced frame structures is calculated using the effective length coefficient method, it cannot reflect the effect of the brace on the frame, the mutual support of columns on the same floor, and vertical interactions between different floors, which is easy to lead to unreasonable design. In this study, based on a spring-rocking column model, the structural transformation concept was used to transform the second-order problem of determining the critical force of braced frame structures into a first-order problem of calculating the lateral stiffness of the structure. First, the repetitive frame element was used to obtain the lateral stiffness of each floor, and the second-order effect coefficient was used to determine the load stiffness of the floor. Next, the lateral stiffness and load stiffness of each floor was assembled. Finally, the principle in which the load stiffness reduces the lateral stiffness of the structure to zero when the braced frame structure buckles laterally were applied to derive a formula to directly calculate the critical force of the flexural-type brace frame structure. This formula reflects the interactions between the braced structure and the frame, the mutual support of columns on the same floor, and the vertical interactions between different floors. Therefore, it can compensate for the deficiency in which the criterion cannot calculate the critical force of braced frame structures and is suitable for quantitatively analyzing the vertical interactions between different floors of braced frame structures.

Zhirui Wang,* Rui Sun,* Cheng Mu, Chunhua Wang, Hui Zhao, Lina Jiang, Hanfang Ju, Wenxi Dai, Fan Zhang Tuberculosis Reference Laboratory, Tianjin Center for Tuberculosis Control, Tianjin, People’s Republic of China*These authors contributed equally to this workCorrespondence: Fan Zhang, Tuberculosis Reference Laboratory, Tianjin Center for Tuberculosis Control, No. 124, Chifeng Road, Heping District, Tianjin, 300041, People’s Republic of China, Tel +86-22-27124491, Fax +86-22-27117595, Email jncdczhf@126.comObjective: Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a global concern. This study aimed to determine the molecular characteristics of fluoroquinolone-resistant and multidrug-resistant M. tuberculosis strains using whole-genome sequencing to predict drug resistance in M. tuberculosis in Tianjin, China, which has not been established previously.Methods: Twenty-one fluoroquinolone-resistant and multidrug-resistant M. tuberculosis strains were isolated from sputum samples. Phenotypic drug resistance against 12 anti-tuberculosis drugs was determined using drug susceptibility testing. Whole-genome sequencing was performed to predict drug resistance in M. tuberculosis based on genome regions associated with drug resistance. The sensitivity of whole-genome sequencing for predicting drug resistance was calculated based on phenotypic drug susceptibility testing information.Results: Among the 21 isolates, mutations in 15 genome regions associated with drug resistance, including rpoB for rifampicin; katG and inhA promoter for isoniazid; gyrA and gyrB for ofloxacin and moxifloxacin; rpsL for streptomycin; rrs for streptomycin, amikacin, kanamycin and capreomycin; pncA and panD for pyrazinamide; embB, embC-embA, aftA, and ubiA for ethambutol; ethA for protionamide; and folC for para-aminosalicylic acid, were detected. Compared with traditional drug susceptibility testing results, the sensitivities for whole-genome sequencing of

Content: Nowadays, protein-based nanoparticle as a biodegradable, biocompatible product attracts considerable interest for new uses in specialized technical areas. Gelatin is a denatured, biodegradable, and nonimmunogenic protein obtained by controlled hydrolysis of the triple-helix structure of collagen into single-strain molecules. As an amphiphilic biopolymer, gelatin can easily assemble into different kinds of aggregates under the defined pH and temperature and the resulting gelatin nanoparticles have been developed to be applied in the food industry and biomedical fields. Herein we report a novel macromolecular microsphere composites (MMC) hydrogels with the use of prepared methacrylated gelatin nanoparticles (MA-GNP) as the cross-linker. MA-GNP have the ability of chemical crosslinking by the polymerization of C=C bonds, such that the composite hydrogels can be formed by radical polymerization of acrylamide (AAm) on the surface of MA-GNP. The smooth spherical particles with an average size of ~100 nm have been synthesized through a modified two-step desolvation method as proved by atomic force microscopy (AFM). The results of nuclear magnetic resonance and dynamic light scattering further confirm the presence of reactive groups (C=C bonds) in the particles and its narrow sizes distribution. The resulting composite hydrogels (MA-GNP/PAAm) are porous materials with tunable pore sizes and exhibit enhanced compressive resistance and elasticity as well. Increasing appropriately the dosage of MA-GNP reduces the equilibrium swelling ratio and improves thermal stability of the gels. Moreover, all the hydrogels exhibit prolonged blood-clotting time, nonhemolytic nature and strong suitability for cell proliferation, indicating the improved antithrombogenicity and excellent cyto-compatibility. It suggests that the novel MA-GNP/PAAm hydrogels have potential application as tissue engineer scaffold materials, and the MA-GNP can be a promising macromolecular microsphere cros

Content: Nowadays, protein-based nanoparticle as a biodegradable, biocompatible product attracts considerable interest for new uses in specialized technical areas. Gelatin is a denatured, biodegradable, and nonimmunogenic protein obtained by controlled hydrolysis of the triple-helix structure of collagen into single-strain molecules. As an amphiphilic biopolymer, gelatin can easily assemble into different kinds of aggregates under the defined pH and temperature and the resulting gelatin nanoparticles have been developed to be applied in the food industry and biomedical fields. Herein we report a novel macromolecular microsphere composites (MMC) hydrogels with the use of prepared methacrylated gelatin nanoparticles (MA-GNP) as the cross-linker. MA-GNP have the ability of chemical crosslinking by the polymerization of C=C bonds, such that the composite hydrogels can be formed by radical polymerization of acrylamide (AAm) on the surface of MA-GNP. The smooth spherical particles with an average size of ~100 nm have been synthesized through a modified two-step desolvation method as proved by atomic force microscopy (AFM). The results of nuclear magnetic resonance and dynamic light scattering further confirm the presence of reactive groups (C=C bonds) in the particles and its narrow sizes distribution. The resulting composite hydrogels (MA-GNP/PAAm) are porous materials with tunable pore sizes and exhibit enhanced compressive resistance and elasticity as well. Increasing appropriately the dosage of MA-GNP reduces the equilibrium swelling ratio and improves thermal stability of the gels. Moreover, all the hydrogels exhibit prolonged blood-clotting time, nonhemolytic nature and strong suitability for cell proliferation, indicating the improved antithrombogenicity and excellent cyto-compatibility. It suggests that the novel MA-GNP/PAAm hydrogels have potential application as tissue engineer scaffold materials, and the MA-GNP can be a promising macromolecular microsphere cros

Content: Nowadays, protein-based nanoparticle as a biodegradable, biocompatible product attracts considerable interest for new uses in specialized technical areas. Gelatin is a denatured, biodegradable, and nonimmunogenic protein obtained by controlled hydrolysis of the triple-helix structure of collagen into single-strain molecules. As an amphiphilic biopolymer, gelatin can easily assemble into different kinds of aggregates under the defined pH and temperature and the resulting gelatin nanoparticles have been developed to be applied in the food industry and biomedical fields. Herein we report a novel macromolecular microsphere composites (MMC) hydrogels with the use of prepared methacrylated gelatin nanoparticles (MA-GNP) as the cross-linker. MA-GNP have the ability of chemical crosslinking by the polymerization of C=C bonds, such that the composite hydrogels can be formed by radical polymerization of acrylamide (AAm) on the surface of MA-GNP. The smooth spherical particles with an average size of ~100 nm have been synthesized through a modified two-step desolvation method as proved by atomic force microscopy (AFM). The results of nuclear magnetic resonance and dynamic light scattering further confirm the presence of reactive groups (C=C bonds) in the particles and its narrow sizes distribution. The resulting composite hydrogels (MA-GNP/PAAm) are porous materials with tunable pore sizes and exhibit enhanced compressive resistance and elasticity as well. Increasing appropriately the dosage of MA-GNP reduces the equilibrium swelling ratio and improves thermal stability of the gels. Moreover, all the hydrogels exhibit prolonged blood-clotting time, nonhemolytic nature and strong suitability for cell proliferation, indicating the improved antithrombogenicity and excellent cyto-compatibility. It suggests that the novel MA-GNP/PAAm hydrogels have potential application as tissue engineer scaffold materials, and the MA-GNP can be a promising macromolecular microsphere cros

Chunhua Wang,1 Guohui Xu,2 Ge Wu,2 Zhiming Chen,3 Zhiyong Sun,4 Ping Zheng,5 Yecai Huang,6 Fuqiang Wang,7 Xuegang Yang2 1Department of Radiology, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Radiation Oncology Key Laboratory of Sichuan Province, Chengdu, Sichuan 610041, People’s Republic of China; 2Department of Interventional Radiology, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Radiation Oncology Key Laboratory of Sichuan Province, Chengdu, Sichuan 610041, People’s Republic of China; 3PET/CT Center, The General Hospital of Western Theater Command, Chengdu, Sichuan 610083, People’s Republic of China; 4Nuclear Department, The General Hospital of Western Theater Command, Chengdu, Sichuan 610083, People’s Republic of China; 5Department of Pathology, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Radiation Oncology Key Laboratory of Sichuan Province, Chengdu, Sichuan 610041, People’s Republic of China; 6Department of Radiation Oncology, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Radiation Oncology Key Laboratory of Sichuan Province, Chengdu, Sichuan 610041, People’s Republic of China; 7Department of Interventional Radiology, Linshui County People’s Hospital, Guang’an, Sichuan 638500, People’s Republic of ChinaCorrespondence: Xuegang YangDepartment of Interventional Radiology, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Radiation Oncology Key Laboratory of Sichuan Province, No.55, Lane 4, RenMin Road (South), Che

Guang-Yu Wang,1,* Ling Li,2,* Bo Liu,1 Xiao Han,1 Chun-Hua Wang,1 Ji-Wen Wang3 1Department of Neurosurgery, 2Department of Pediatrics, Qilu Children’s Hospital of Shandong University, Jinan, Shandong, 3Department of Neurology, Shanghai Children’s Medical Center, Shanghai Jiaotong University School of Medicine, Pudong New District, Shanghai, People’s Republic of China *These authors contributed equally to this work Purpose: This study aimed to explore significant genes and pathways involved in the pathogenesis of supratentorial primitive neuroectodermal tumor (sPNET). Materials and methods: Gene expression profile of GSE14295 was downloaded from publicly available Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened out in primary sPNET samples compared with normal fetal and adult brain reference samples (sPNET vs fetal brain and sPNET vs adult brain). Pathway enrichment analysis of these DEGs was conducted, followed by protein–protein interaction (PPI) network construction and significant module selection. Additionally, transcription factors (TFs) regulating the common DEGs in the two comparison groups were identified, and the regulatory network was constructed. Results: In total, 526 DEGs (99 up- and 427 downregulated) in sPNET vs fetal brain and 815 DEGs (200 up- and 615 downregulated) in sPNET vs adult brain were identified. DEGs in sPNET vs fetal brain and sPNET vs adult brain were associated with calcium signaling pathway, cell cycle, and p53 signaling pathway. CDK1, CDC20, BUB1B, and BUB1 were hub nodes in the PPI networks of DEGs in sPNET vs fetal brain and sPNET vs adult brain. Significant modules were extracted from the PPI networks. In addition, 64 upregulated and 200 downregulated overlapping DEGs were identified in both sPNET vs fetal brain and sPNET vs adult brain. The genes involved in the regulatory network upon overlapping DEGs and the TFs were c

Problembakgrund: Ska ett företags verksamhet drivas för att maximera aktieägarvärde eller tillgodose alla intressenters intressen är en fråga som varit fokus för mycket forskning. Många forskare har undersökt vad som påverkar valet av bolagsstyrningsprincip, där ägarstruktur och styrelsesammansättning har lyfts fram som betydande faktorer. Resultaten är dock motstridiga. Eftersom tidigare forskningar har genomförts i olika länder och under olika tidsperioder finns det en god anledning att undersöka om/hur institutionella förhållanden kan påverka sambandet mellan ägarstruktur/styrelsesammansättning och val av bolagsstyrningsprincip. De institutionella miljöer som avses undersökas är Sverige och Kina. Syfte: Syftet med denna studie är att förklara sambandet mellan ägarstruktur/styrelsesammansättning och val av bolagsstyrningsprincip samt hur detta samband påverkas av olika institutionella miljöer. Metod: En deduktiv forskningsansats har legat till grund för studien och teorier som använts och applicerats är aktieägarteori, intressentteori, agentteori, upper echelon teori och institutionell teori. Data för denna kvantitativa forskning hämtas huvudsakligen från Datastream, årsredovisningar från svenska och kinesiska börsnoterade företag gällande åren 2013-2015, företagens hemsidor samt ett sammansatt styrelsematerial. Resultat: När den svenska och kinesiska datan testades tillsammans har det inte påvisats något signifikant samband mellan ägarkoncentration, institutionell ägare som störst ägare, andelen oberoende styrelseledamöter, staten som störst ägare, andelen kvinnliga styrelseledamöter och val av bolagsstyrningsprincip. Institutionella förhållanden har inte heller haft någon signifikant påverkan på sambandet mellan ägarstruktur/styrelsesammansättning och val av bolagsstyrningsprincip. När data för respektive land testades separat har det inte påvisats något signifikant samband mellan studiens beroende och oberoende variabler, förutom att det på den kinesiska markna, Background and problem: Should a company's business be run to maximize shareholder value or meet all stakeholders´ interests is a question that has been the focus of much research. Many researchers have investigated what influences the choice of corporate governance principle, where ownership structure and board composition have been highlighted as significant factors. However, the results are contradictory. Since previous researches have been conducted in different countries and during different periods of time, there is a good reason to investigate whether institutional conditions may affect the relationship between ownership structure / board composition and the choice of corporate governance principle. The institutional environments investigated are Sweden and China. Purpose: The purpose of the study is to explain the relationship between ownership structure / board composition and the choice of corporate governance principle and how this relationship is influenced by various institutional environments. Method: A deductive research approach has been the basis of this study and theories used and applied are shareholder theory, stakeholder theory, agent theory, upper echelon theory and institutional theory. Data for this quantitative research is mainly gathered from Datastream, annual reports from Swedish and Chinese listed companies for 2013- 2015, corporate websites and a composite board material. Results: When the Swedish and Chinese data were tested together, there has been no significant correlation between owner concentration, institutional owners as the largest owner, the proportion of independent directors, the state as the largest owner, the proportion of female board members and the choice of corporate governance principle. Institutional conditions have not had a significant effect on the relationship between ownership structure / board composition and the choice of corporate governance principle. When data for each country was tested separately, there h

Problembakgrund: Ska ett företags verksamhet drivas för att maximera aktieägarvärde eller tillgodose alla intressenters intressen är en fråga som varit fokus för mycket forskning. Många forskare har undersökt vad som påverkar valet av bolagsstyrningsprincip, där ägarstruktur och styrelsesammansättning har lyfts fram som betydande faktorer. Resultaten är dock motstridiga. Eftersom tidigare forskningar har genomförts i olika länder och under olika tidsperioder finns det en god anledning att undersöka om/hur institutionella förhållanden kan påverka sambandet mellan ägarstruktur/styrelsesammansättning och val av bolagsstyrningsprincip. De institutionella miljöer som avses undersökas är Sverige och Kina. Syfte: Syftet med denna studie är att förklara sambandet mellan ägarstruktur/styrelsesammansättning och val av bolagsstyrningsprincip samt hur detta samband påverkas av olika institutionella miljöer. Metod: En deduktiv forskningsansats har legat till grund för studien och teorier som använts och applicerats är aktieägarteori, intressentteori, agentteori, upper echelon teori och institutionell teori. Data för denna kvantitativa forskning hämtas huvudsakligen från Datastream, årsredovisningar från svenska och kinesiska börsnoterade företag gällande åren 2013-2015, företagens hemsidor samt ett sammansatt styrelsematerial. Resultat: När den svenska och kinesiska datan testades tillsammans har det inte påvisats något signifikant samband mellan ägarkoncentration, institutionell ägare som störst ägare, andelen oberoende styrelseledamöter, staten som störst ägare, andelen kvinnliga styrelseledamöter och val av bolagsstyrningsprincip. Institutionella förhållanden har inte heller haft någon signifikant påverkan på sambandet mellan ägarstruktur/styrelsesammansättning och val av bolagsstyrningsprincip. När data för respektive land testades separat har det inte påvisats något signifikant samband mellan studiens beroende och oberoende variabler, förutom att det på den kinesiska markna, Background and problem: Should a company's business be run to maximize shareholder value or meet all stakeholders´ interests is a question that has been the focus of much research. Many researchers have investigated what influences the choice of corporate governance principle, where ownership structure and board composition have been highlighted as significant factors. However, the results are contradictory. Since previous researches have been conducted in different countries and during different periods of time, there is a good reason to investigate whether institutional conditions may affect the relationship between ownership structure / board composition and the choice of corporate governance principle. The institutional environments investigated are Sweden and China. Purpose: The purpose of the study is to explain the relationship between ownership structure / board composition and the choice of corporate governance principle and how this relationship is influenced by various institutional environments. Method: A deductive research approach has been the basis of this study and theories used and applied are shareholder theory, stakeholder theory, agent theory, upper echelon theory and institutional theory. Data for this quantitative research is mainly gathered from Datastream, annual reports from Swedish and Chinese listed companies for 2013- 2015, corporate websites and a composite board material. Results: When the Swedish and Chinese data were tested together, there has been no significant correlation between owner concentration, institutional owners as the largest owner, the proportion of independent directors, the state as the largest owner, the proportion of female board members and the choice of corporate governance principle. Institutional conditions have not had a significant effect on the relationship between ownership structure / board composition and the choice of corporate governance principle. When data for each country was tested separately, there h

Solar energy is a prominent renewable source of electricity if cheap methods are designed for its concentration and conversion. With the purpose of improving power conversion efficiency and lowering the cost, luminescent solar concentrations (LSCs) are developed for collecting and concentrating both direct and diffuse light for Photovoltaic systems without tracking. Nano-structured near infrared PbS quantum dots (QDs) as new luminescent materials are identified. This material is optically characterized by using steady state spectroscopic technologies and electrically characterized by outdoor testing. These properties are also compared with visible CdSe/ZnS QDs for LSC PV systems and organic dye LSC PV systems. The results show the promising future of near infrared QDs as luminescent material for LSCs if their stability can be properly controlled. Techniques for fabrication and characterization of LSCs as "smart" windows are developed. A range of prototypes are fabricated, optically and electrically characterized. A variety of optimal designs for improving the output power conversion efficiency are investigated both for QDs LSCs and for organic dye LSCs. For LSCs with organic dyes, the size dependent optimization methods are developed for both one layer and stacked structures. The largest fabricated prototype has 60cm by 120cm by 0.32cm. It yields electric gain 4.23, which is much larger than that of fixed concentrators based on geometrical optics. Prototypes fabricated with new outdoor use organic laser dyes show the same electric gain but with 5.88x smaller in size 2.67x larger in optical efficiency. This results show that LSCs fabricated with outdoor use organic dyes are very promising if applied into stacked structures. New generation LSCs with liquid crystals as matrix materials are explored. Properties of liquid crystals and dyes for the new generation LSCs are analyzed with the predicted theoretical improvement for trapping efficiency up to 21.3%. Such anisotr

Solar energy is a prominent renewable source of electricity if cheap methods are designed for its concentration and conversion. With the purpose of improving power conversion efficiency and lowering the cost, luminescent solar concentrations (LSCs) are developed for collecting and concentrating both direct and diffuse light for Photovoltaic systems without tracking. Nano-structured near infrared PbS quantum dots (QDs) as new luminescent materials are identified. This material is optically characterized by using steady state spectroscopic technologies and electrically characterized by outdoor testing. These properties are also compared with visible CdSe/ZnS QDs for LSC PV systems and organic dye LSC PV systems. The results show the promising future of near infrared QDs as luminescent material for LSCs if their stability can be properly controlled. Techniques for fabrication and characterization of LSCs as "smart" windows are developed. A range of prototypes are fabricated, optically and electrically characterized. A variety of optimal designs for improving the output power conversion efficiency are investigated both for QDs LSCs and for organic dye LSCs. For LSCs with organic dyes, the size dependent optimization methods are developed for both one layer and stacked structures. The largest fabricated prototype has 60cm by 120cm by 0.32cm. It yields electric gain 4.23, which is much larger than that of fixed concentrators based on geometrical optics. Prototypes fabricated with new outdoor use organic laser dyes show the same electric gain but with 5.88x smaller in size 2.67x larger in optical efficiency. This results show that LSCs fabricated with outdoor use organic dyes are very promising if applied into stacked structures. New generation LSCs with liquid crystals as matrix materials are explored. Properties of liquid crystals and dyes for the new generation LSCs are analyzed with the predicted theoretical improvement for trapping efficiency up to 21.3%. Such anisotr

A low-voltage high-linearity wideband current differencing transconductance amplifier (CDTA) is presented in this paper. The CDTA consists of a current differencing circuit and a cross-coupling transconductance circuit. The PSPICE simulations of the proposed CDTA show a good performance: -3dB frequency bandwith is about 900 MHz, low power consumption is 2.48 mW, input current linear range is ±100 µA and low current-input resistance is less than 20 Ω, high current-output resistance is more than 3 MΩ. PSpice simulations for a current-mode universal filter and a proposed high-order filter are also conducted, and the results verify the validity of the proposed CDTA.

We have performed a series of thermodynamic measurements and molecular dynamics (MD) simulations to study the interactions between the neurotransmitters (NTs) 5-hydroxytryptamine (5-HT), g-aminobutyrate (GABA), glycine (GLY), acetylcholine (ACH) and glutamate (GLU) as well as the amidated / acetylated g-aminobutyrate (GABAneu) with a dipalmitoylphosphatidylcholine (DPPC) bilayer. This study was motivated by recent research results that suggested that neural transmission may also be affected by nonspecific interactions of NTs with the lipid matrix of the synaptic membrane. Our results revealed that dependent on the nature of NTs, some of the NTs penetrate into the bilayer. We found that membrane affinity can be ranked with increasing affinity as follows: ACH ~ GLU << GABA < GLY << GABAneu << 5-HT. The latter three penetrated the bilayer at most with the deepest location being close to the glycerol backbone of the phospholipids. It is surprising that hydrophilic solutes can deeply penetrate into the membrane pointing to the fact that membrane affinity is governed by specific interactions. Our MD simulations identified the salt-bridge between the primary amine of NTs and the lipid phosphate group as the most important interaction by which the NTs are anchored to the membrane. These distinctive interactions could be related to nonspecific effects of these neurotransmitters and could point to a bilayer-mediated modulation of nerve transmission. However, due to the strong variability in affinity observed for the different NTs, this attraction is not an inherent property of all neurotransmitters.

Serotonin (5-hydroxytryptamine, 5-HT) is a prevalent neurotransmitter throughout the animal kingdom. It exerts its effect through the specific binding to the serotonin receptor, but recent research has suggested that neural transmission may also be affected by its nonspecific interactions with the lipid matrix of the synaptic membrane. However, membrane–5-HT interactions remain controversial and superficially investigated. Fundamental knowledge of this interaction appears vital in discussions of putative roles of 5-HT, and we have addressed this by thermodynamic measurements and molecular dynamics (MD) simulations. 5-HT was found to interact strongly with lipid bilayers (partitioning coefficient ∼1200 in mole fraction units), and this is highly unusual for a hydrophilic solute like 5-HT which has a bulk, oil–water partitioning coefficient well below unity. It follows that membrane affinity must rely on specific interactions, and the MD simulations identified the salt-bridge between the primary amine of 5-HT and the lipid phosphate group as the most important interaction. This interaction anchored cationic 5-HT in the membrane interface with the aromatic ring system pointing inward and a prevailing residence between the phosphate and the carbonyl groups of the lipid. The unprotonated form of 5-HT shows the opposite orientation, with the primary amine pointing toward the membrane core. Partitioning of 5-HT was found to decrease lipid chain order. These distinctive interactions of 5-HT and model membranes could be related to nonspecific effects of this neurotransmitter.

Weak interactions of neurotransmitters and the lipid matrix in the synaptic membrane have been hypothesized to play a role in synaptic transmission of nerve signals, particularly with respect to receptor desensitization (Cantor, R. S. Biochemistry 2003, 42, 11891). The strength of such interactions, however, was not measured, and this is an obvious impediment for further evaluation and understanding of a possible role for desensitization. We have used dialysis equilibrium to directly measure the net affinity of selected neurotransmitters for lipid membranes and analyzed this affinity data with respect to calorimetric measurements and molecular dynamics simulations. We studied an anionic (glutamate), a cationic (acetylcholine), and two zwitterionic (-aminobutyric acid and glycine) neurotransmitters, and membranes of pure dimyristoyl phosphatidylcholine (DMPC), DMPC doped with 10% anionic lipid (dimyristoyl phosphatidylglycerol, DMPG, or dimyristoyl phosphatidylserine, DMPS), or 1:1 mixtures of dipalmitoyl phosphatidylcholine (DPPC) and dilauroyl phosphatidylcholine (DLPC). The results showed a remarkable variability among the investigated systems. For example, the chloride salt of acetylcholine interacts unfavorably with DMPC and is thus preferentially excluded from the membrane's hydration layer. Conversely, the zwitterionic neurotransmitters are attracted to membranes with 10% anionic lipid and their local concentration at the interface is 5-10 times larger than in the aqueous bulk. The simulations suggest that this attraction mainly relies on electrostatic interactions of the amino group of the neurotransmitter and the lipid phosphate. We conclude that moderate attraction to lipid membranes occurs for some polar neurotransmitters and hence that one premise for a theory of bilayer-mediated modulation of nerve transmission seems to be fulfilled. However, the strong variability in interaction strengths also shows that this attraction is not an inherent property of al

It is well established that small sugars exert different types of stabilization of biomembranes both in vivo and in vitro. However, the essential question of whether sugars are bound to or expelled from membrane surfaces, i.e., the sign and size of the free energy of the interaction, remains unresolved, and this prevents a molecular understanding of the stabilizing mechanism. We have used small-angle neutron scattering and thermodynamic measurements to show that sugars may be either bound or expelled depending on the concentration of sugar. At low concentration, small sugars bind quite strongly to a lipid bilayer, and the accumulation of sugar at the interface makes the membrane thinner and laterally expanded. Above â¼0.2 M the sugars gradually become expelled from the membrane surface, and this repulsive mode of interaction counteracts membrane thinning. The dual nature of sugar-membrane interactions offers a reconciliation of conflicting views in earlier reports on sugar-induced modulations of membrane properties.

This paper proposes a new current conveyorbased high-output impedance single-input three-output current mode filter with minimum configuration. It contains two dual output second generation current conveyors, one third generation dual output current conveyor, and four grounded resistors and capacitors. The circuit simultaneously provides low-pass, band-pass, and high-pass filtering outputs, without any passive component matching conditions and restrictions on input signals. Additionally, the proposed circuit offers following advantages: Minimum active and passive element count, high output and low input impedances, suitable for cascading identical currentmode sections, all passive elements are grounded (no virtual grounding), low natural frequency and Q-factor sensitivities. The influences of non-ideal current conveyors on the proposed circuit are researched in the last.

In this paper, a systematic design method producing balanced current-mode filters is proposed, using current controlled fully balanced second-generation current conveyor circuit (CFBCCII). In this method, many kind of all-pole multiple loop feedback (MF) current mode balanced filters can be obtained, all the produced filters have fully balance structures. Moreover, the frequency of the filters can be electronically adjustable. The produced nth-order filters are constructed by n CFBCCIIs and 2n grounded capacitors, no resistors are needed. The sensitivities of the filters and influences of CFBCCII parasitic elements on filters are analyzed.

In this paper, a systematic design method producing balanced current-mode filters is proposed, using current controlled fully balanced second-generation current conveyor circuit (CFBCCII). In this method, many kind of all-pole multiple loop feedback (MF) current mode balanced filters can be obtained, all the produced filters have fully balance structures. Moreover, the frequency of the filters can be electronically adjustable. The produced nth-order filters are constructed by n CFBCCIIs and 2n grounded capacitors, no resistors are needed. The sensitivities of the filters and influences of CFBCCII parasitic elements on filters are analyzed.

This paper proposes a new current conveyorbased high-output impedance single-input three-output current mode filter with minimum configuration. It contains two dual output second generation current conveyors, one third generation dual output current conveyor, and four grounded resistors and capacitors. The circuit simultaneously provides low-pass, band-pass, and high-pass filtering outputs, without any passive component matching conditions and restrictions on input signals. Additionally, the proposed circuit offers following advantages: Minimum active and passive element count, high output and low input impedances, suitable for cascading identical currentmode sections, all passive elements are grounded (no virtual grounding), low natural frequency and Q-factor sensitivities. The influences of non-ideal current conveyors on the proposed circuit are researched in the last.

In this paper, a systematic design method producing balanced current-mode filters is proposed, using current controlled fully balanced second-generation current conveyor circuit (CFBCCII). In this method, many kind of all-pole multiple loop feedback (MF) current mode balanced filters can be obtained, all the produced filters have fully balance structures. Moreover, the frequency of the filters can be electronically adjustable. The produced nth-order filters are constructed by n CFBCCIIs and 2n grounded capacitors, no resistors are needed. The sensitivities of the filters and influences of CFBCCII parasitic elements on filters are analyzed.

A coplanar waveguide (CPW) fed novel planar ultra-wideband antenna with a band-notch characteristic is presented. The proposed antenna consists of a rectangular metal radiation patch and a tapered arc-shaped ground plane. To achieve ultra wideband, three modifications are introduced, the first one is to remove a 90-degree fan angle on the upper corners of the patch, the second one is to shape the bottom of the patch into an arc, and the third modification is to remove a small fan angle on each side of the ground plane near the feeding line. Simulation results show that the proposed antenna operates over 3.0 to 23 GHz for VSWR < 2. By embedding a C-shaped slot in the radiating patch, a frequency band notch between the bandwidth of 5 to 6 GHz for Wireless LAN (WLAN) will be obtained. All simulations in this work were carried out by using the electromagnetic software Ansoft HFSS 11. Compared with the recently proposed antennas, this antenna has advantages in wide bandwidth, good band-notch characteristic, compact in size and easy design. Details of the proposed antenna are presented, and simulated results show that the antenna has stable radiation patterns and good gain flatness over its whole frequency band.

Reflectance difference/anisotropy spectroscopy (RDS/RAS) has become a widely used technique to measure the anisotropy in materials since its development in the late 80‘s. It is often performed as a function of wavelength and the specific peaks can provide much information of the structure and electronic state in a material. In this thesis I demonstrate the new applications of spatially resolved microscopic-RDS (micro-RDS). In this study, anisotropic domains were observed in epitaxial AlN layers grown on Si and sapphire substrates. They were identified to be strain domains and the strain calculated from the RD signal corresponded well with most existing experimental values. Depending on the growth process the strain domains were in the sub-micrometer to several micrometers scale. Each domain consists of hundreds of AlN grains. Anisotropic domains were also observed in magnetic CrSe/Fe and La0.7Sr0.3MnO3 materials. They changed under external fields so we knew they were related to magnetization. By adjusting the aperture between the objective lens and the sample surface, the in-plane magnetization and off-plane magnetization can be discriminated. Geometrical optical approximation was found inapplicable to the experiments and we proposed an explanation based on nano-optical principle. The temperature-dependence MDs in CrSe/Fe, La0.7Sr0.3MnO3 and Ga0.95Mn0.05As were studied. The size of MDs was observed to increase when the temperature was lowered. For GaMnAs, the formation of MDs was observed when the temperature decreased from above the Curie temperature Tc to below Tc. We also used the micro-RDS to search the spin Hall Effect in several kinds of semiconductor materials including InGaAs/InAlAs, ZnSe, and HgTe. No spin accumulation was detected at the unit edges, meaning no spin Hall Effect existed. The reason may lie on the serious scattering caused by the defects. Finally the potential applications of micro-RDS in condensed matter physics were discussed.

Reflectance difference/anisotropy spectroscopy (RDS/RAS) has become a widely used technique to measure the anisotropy in materials since its development in the late 80‘s. It is often performed as a function of wavelength and the specific peaks can provide much information of the structure and electronic state in a material. In this thesis I demonstrate the new applications of spatially resolved microscopic-RDS (micro-RDS). In this study, anisotropic domains were observed in epitaxial AlN layers grown on Si and sapphire substrates. They were identified to be strain domains and the strain calculated from the RD signal corresponded well with most existing experimental values. Depending on the growth process the strain domains were in the sub-micrometer to several micrometers scale. Each domain consists of hundreds of AlN grains. Anisotropic domains were also observed in magnetic CrSe/Fe and La0.7Sr0.3MnO3 materials. They changed under external fields so we knew they were related to magnetization. By adjusting the aperture between the objective lens and the sample surface, the in-plane magnetization and off-plane magnetization can be discriminated. Geometrical optical approximation was found inapplicable to the experiments and we proposed an explanation based on nano-optical principle. The temperature-dependence MDs in CrSe/Fe, La0.7Sr0.3MnO3 and Ga0.95Mn0.05As were studied. The size of MDs was observed to increase when the temperature was lowered. For GaMnAs, the formation of MDs was observed when the temperature decreased from above the Curie temperature Tc to below Tc. We also used the micro-RDS to search the spin Hall Effect in several kinds of semiconductor materials including InGaAs/InAlAs, ZnSe, and HgTe. No spin accumulation was detected at the unit edges, meaning no spin Hall Effect existed. The reason may lie on the serious scattering caused by the defects. Finally the potential applications of micro-RDS in condensed matter physics were discussed.

A coplanar waveguide (CPW) fed novel planar ultra-wideband antenna with a band-notch characteristic is presented. The proposed antenna consists of a rectangular metal radiation patch and a tapered arc-shaped ground plane. To achieve ultra wideband, three modifications are introduced, the first one is to remove a 90-degree fan angle on the upper corners of the patch, the second one is to shape the bottom of the patch into an arc, and the third modification is to remove a small fan angle on each side of the ground plane near the feeding line. Simulation results show that the proposed antenna operates over 3.0 to 23 GHz for VSWR < 2. By embedding a C-shaped slot in the radiating patch, a frequency band notch between the bandwidth of 5 to 6 GHz for Wireless LAN (WLAN) will be obtained. All simulations in this work were carried out by using the electromagnetic software Ansoft HFSS 11. Compared with the recently proposed antennas, this antenna has advantages in wide bandwidth, good band-notch characteristic, compact in size and easy design. Details of the proposed antenna are presented, and simulated results show that the antenna has stable radiation patterns and good gain flatness over its whole frequency band.

A coplanar waveguide (CPW) fed novel planar ultra-wideband antenna with a band-notch characteristic is presented. The proposed antenna consists of a rectangular metal radiation patch and a tapered arc-shaped ground plane. To achieve ultra wideband, three modifications are introduced, the first one is to remove a 90-degree fan angle on the upper corners of the patch, the second one is to shape the bottom of the patch into an arc, and the third modification is to remove a small fan angle on each side of the ground plane near the feeding line. Simulation results show that the proposed antenna operates over 3.0 to 23 GHz for VSWR < 2. By embedding a C-shaped slot in the radiating patch, a frequency band notch between the bandwidth of 5 to 6 GHz for Wireless LAN (WLAN) will be obtained. All simulations in this work were carried out by using the electromagnetic software Ansoft HFSS 11. Compared with the recently proposed antennas, this antenna has advantages in wide bandwidth, good band-notch characteristic, compact in size and easy design. Details of the proposed antenna are presented, and simulated results show that the antenna has stable radiation patterns and good gain flatness over its whole frequency band.

Reflectance difference/anisotropy spectroscopy (RDS/RAS) has become a widely used technique to measure the anisotropy in materials since its development in the late 80‘s. It is often performed as a function of wavelength and the specific peaks can provide much information of the structure and electronic state in a material. In this thesis I demonstrate the new applications of spatially resolved microscopic-RDS (micro-RDS). In this study, anisotropic domains were observed in epitaxial AlN layers grown on Si and sapphire substrates. They were identified to be strain domains and the strain calculated from the RD signal corresponded well with most existing experimental values. Depending on the growth process the strain domains were in the sub-micrometer to several micrometers scale. Each domain consists of hundreds of AlN grains. Anisotropic domains were also observed in magnetic CrSe/Fe and La0.7Sr0.3MnO3 materials. They changed under external fields so we knew they were related to magnetization. By adjusting the aperture between the objective lens and the sample surface, the in-plane magnetization and off-plane magnetization can be discriminated. Geometrical optical approximation was found inapplicable to the experiments and we proposed an explanation based on nano-optical principle. The temperature-dependence MDs in CrSe/Fe, La0.7Sr0.3MnO3 and Ga0.95Mn0.05As were studied. The size of MDs was observed to increase when the temperature was lowered. For GaMnAs, the formation of MDs was observed when the temperature decreased from above the Curie temperature Tc to below Tc. We also used the micro-RDS to search the spin Hall Effect in several kinds of semiconductor materials including InGaAs/InAlAs, ZnSe, and HgTe. No spin accumulation was detected at the unit edges, meaning no spin Hall Effect existed. The reason may lie on the serious scattering caused by the defects. Finally the potential applications of micro-RDS in condensed matter physics were discussed.

Fe/Zn0.96Fe0.04S Schottky diode was grown by molecular beam epitaxy. The short-circuit DC photocurrent spectroscopy was measured at temperatures from 10 to 300 K. Anomalous photocurrent was observed at temperatures above 100 K when excitation photon energies were less than the band gap energy of Zn0.96Fe0.04S. We have explained this anomalous phenomenon based on the photo-ionization of acceptor-like interface states. We believe that these interface states are associated with some complex (Fe,S) defects formed at the Fe/ZnFeS interface. The transient behavior of photocurrent at various temperatures has also been studied. (C) 2007 Elsevier B.V. All rights reserved.

Fe/Zn0.96Fe0.04S Schottky diode was grown by molecular beam epitaxy. The short-circuit DC photocurrent spectroscopy was measured at temperatures from 10 to 300 K. Anomalous photocurrent was observed at temperatures above 100 K when excitation photon energies were less than the band gap energy of Zn0.96Fe0.04S. We have explained this anomalous phenomenon based on the photo-ionization of acceptor-like interface states. We believe that these interface states are associated with some complex (Fe,S) defects formed at the Fe/ZnFeS interface. The transient behavior of photocurrent at various temperatures has also been studied. (C) 2007 Elsevier B.V. All rights reserved.

Fe/Zn0.96Fe0.04S Schottky diode was grown by molecular beam epitaxy. The short-circuit DC photocurrent spectroscopy was measured at temperatures from 10 to 300 K. Anomalous photocurrent was observed at temperatures above 100 K when excitation photon energies were less than the band gap energy of Zn0.96Fe0.04S. We have explained this anomalous phenomenon based on the photo-ionization of acceptor-like interface states. We believe that these interface states are associated with some complex (Fe,S) defects formed at the Fe/ZnFeS interface. The transient behavior of photocurrent at various temperatures has also been studied. (C) 2007 Elsevier B.V. All rights reserved.

This paper reports on the use of two kinds of cotton fibre/chitosan composite adsorbents (with a Schiff-based bond, SCCH, and a C-N bond, RCCH) to adsorb Au(III) ions from aqueous solution. The adsorption kinetics and adsorption isotherms of the two fibres for Au(III) were investigated. The experimental results revealed that the adsorption kinetics of SCCH and RCCH fibers for Au(III) was described by the pseudo second-order reaction model., This paper reports on the use of two kinds of cotton fibre/chitosan composite adsorbents (with a Schiff-based bond, SCCH, and a C-N bond, RCCH) to adsorb Au(III) ions from aqueous solution. The adsorption kinetics and adsorption isotherms of the two fibres for Au(III) were investigated. The experimental results revealed that the adsorption kinetics of SCCH and RCCH fibers for Au(III) was described by the pseudo second-order reaction model.

China has implemented an emission trading system (ETS) to reduce its ever-increasing greenhouse gas emissions while maintaining rapid economic growth. With low carbon prices and infrequent allowance trading, whether China’s ETS is an effective approach for climate mitigation has entered the center of the policy and research debate. Utilizing China’s regional ETS pilots as a quasi-natural experiment, we provide a comprehensive assessment of the effects of ETS on firm carbon emissions and economic outcomes by means of a matched difference-in-differences (DID) approach. The empirical analysis is based on a unique panel dataset of firm tax records in the manufacturing and public utility sectors during 2009 to 2015. We show unambiguous evidence that the regional ETS pilots are effective in reducing firm emissions, leading to a 16.7% reduction in total emissions and a 9.7% reduction in emission intensity. Regulated firms achieve emission abatement through conserving energy consumption and switching to low-carbon fuels. The economic consequences of the ETS are mixed. On one hand, the ETS has a negative impact on employment and capital input; on the other hand, the ETS incentivizes regulated firms to improve productivity. In the aggregate, the ETS does not exhibit statistically significant effects on output and export. We also find that the ETS displays notable heterogeneity across pilots. Mass-based allowance allocation rules, higher carbon prices, and active allowance trading contribute to more pronounced effects in emission abatement.