bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface‐printed microdot array chips coupled with matrix‐assisted laser desorption/ionization mass spectrometry for high‐throughput single‐cell patterning and phospholipid analysis
Authors: Yang Ti , Gao Dan , Jin Feng , Jiang Yuyang , Liu Hongxia 
Published: August 2016

RationaleSingle‐cell analysis is very important in several research fields for the heterogeneity of individual cells, which has been well accepted. However, restricted by the size and low content of a single cell, current studies have encountered challenges in high‐throughput, high‐space resolution and sensitivity, and multicomponent analysis. A methodology of a surface‐printed microdot array chip coupled with matrix‐assisted laser desorption ionization mass spectrometry (MALDI‐MS) is presented in this study for high‐throughput single‐cell patterning and phospholipid analysis.MethodsThe poly‐L‐lysine (PLL) used as ink molecule was printed on an oxygen plasma processed indium tin oxide (ITO)‐coated glass slide to form a microdot array by micro‐contact printing technology. The cell array was then formed on the PLL microarray through electrostatic adsorption force. 9‐Aminoacridine (9‐AA) matrix was applied on the cell array before it was analyzed by MALDI‐TOF MS. MALDI mass spectrometry imaging (MALDI‐MSI) was then used for high‐throughput, quick measurement, and multicomponent analysis of the cell array.ResultsThe single‐cell capture efficiency of the cell array formed on the PLL microarray was about 40%. Twelve phospholipids were detected at the single‐cell level, and the structures were further confirmed by MS/MS. The MALDI‐MSI of selected ions showed a conformity with the cell array. The relative signal intensity data of selected ions were extracted from every pixel in the image within several minutes. The heterogeneity between individual cells was revealed from the relative signal intensity of phospholipids in 1–3 cells.ConclusionsCompared to the existing related approaches, high‐throughput, quick measurement, and multicomponent single‐cell analysis have been realized by our method. Through different ink molecules used for micro‐contact printing, the established platform could have the potential to capture and analyze specific cells. Copyright © 2016 John Wiley & Sons, Ltd.
Rapid screening and determination of 11 new psychoactive substances by direct analysis in real time mass spectrometry and liquid chromatography/quadrupole time‐of‐flight mass spectrometry
Authors: Nie Honggang , Li Xianjiang , Hua Zhendong , Pan Wei , Bai Yanping , Fu Xiaofang 
Published: August 2016

RationaleWith the amounts and types of new psychoactive substances (NPSs) increasing rapidly in recent years, an excellent high‐throughput method for the analysis of these compounds is urgently needed. In this article, a rapid screening method and a quantitative analysis method for 11 NPSs are described and compared, respectively.MethodA simple direct analysis in real time mass spectrometry (DART‐MS) method was developed for the analysis of 11 NPSs including three categories of these substances present on the global market such as four cathinones, one phenylethylamine, and six synthetic cannabinoids. In order to analyze these compounds quantitatively with better accuracy and sensitivity, another rapid analytical method with a low limit of detection (LOD) was also developed using liquid chromatography/electrospray ionization quadrupole time‐of‐flight mass spectrometry (LC/QTOFMS).ResultsThe 11 NPSs could be determined within 0.5 min by DART‐MS. Furthermore, they could also be separated and determined within 5 min by the LC/QTOFMS method. The two methods both showed good linearity with correlation coefficients (r2) higher than 0.99. The LODs for all these target NPSs by DART‐MS and LC/QTOFMS ranged from 5 to 40 ng mL−1 and 0.1 to 1 ng mL−1, respectively. Confiscated samples, named as “music vanilla” and “bath salt”, and 11 spiked samples were firstly screened by DART‐MS and then determined by LC/QTOFMS.ConclusionsThe identification of NPSs in confiscated materials was successfully achieved, and the proposed analytical methodology could offer rapid screening and accurate analysis results. Copyright © 2016 John Wiley & Sons, Ltd.
Mechanism investigation of HS radical and CS losses from positively charged biradicals of diphenyl sulfides by APCI mass spectrometry
Authors: Cao Xiaoji , Wang Chenlu , Mo Weimin 
Published: August 2016

RationaleAryl thioethers are potentially useful precursors for constructing various biologically active sulfur‐containing heterocycles. The detailed relationship between the losses of HS radical and CS with the spin multiplicity of positively charged diphenyl sulfide biradicals derived from 3‐iodophenyl phenyl sulfides has not been obtained by tandem mass spectrometry combined with theoretical calculations.MethodsCollision‐induced dissociation mass spectrometry experiments were carried out using an ion trap mass spectrometer with APCI in positive mode. The MS/MS experiment for dibenzothiophene was performed by CI triple‐quadrupole mass spectrometry in positive ion mode. The accurate masses of fragments were obtained by reflective TOFMS with an EI source. Theoretical calculations were achieved by the density functional theory method at the B3LYP level with the 6−31+G(d, p) basis set in the Gaussian 03 package of programs.ResultsIn the fragmentation of positively charged diphenyl sulfide biradicals, losses of HS· and CS were observed, which were proposed to originate from spin multiplicity transformation from a triplet ground state to a singlet excited state and a phenyl radical shift in triplet ground state, respectively. Moreover, a protonated dibenzothiophene intermediate was confirmed to exist in the process of HS radical loss. A linear correlation was established between the product ion abundance from the two competitive losses and the Hammett constants (σ) of substituent groups on the benzene ring.ConclusionsThe eliminations of HS· and CS in the fragmentation of positively charged diphenyl sulfide biradicals were triggered by spin multiplicity transformation from a triplet ground state to a singlet excited state and a phenyl radical shift in a triplet ground state, respectively. Based on theoretical calculations, two competitive neutral losses are thermodynamically controlled. Copyright © 2016 John Wiley & Sons, Ltd.
Two competitive INC‐mediated reactions in the gas‐phase fragmentation of protonated indolyl benzo[b]carbazoles
Authors: Zhang Xiaoping , Jiang Kezhi , Zou Jingfeng , Li Zuguang , Lee Mawrong 
Published: August 2016

RationaleIon‐neutral complexes (INCs) are intermediates extensively existing in gas‐phase ionic reactions.MethodsTandem mass spectrometry (MSn) analysis of indolyl benzo[b]carbazoles was performed on an electrospray ionization quadrupole time‐of‐flight (ESI‐Q‐TOF) mass spectrometer in positive ion mode.ResultsTwo competing INC‐mediated reactions were obtained in the fragmentation of protonated indolyl benzo[b]‐carbazoles.ConclusionsThis study enriches our knowledge of the important roles of INCs in the dissociation of indole compounds in the gas phase. Copyright © 2016 John Wiley & Sons, Ltd.
Characterization and application of droplet spray ionization for real‐time reaction monitoring
Authors: Zhang Hong , Li Na , Li Xiao‐di , Jiang Jie , Zhao Dan‐dan , You Hong 
Published: August 2016

RationaleThe ionization source for real‐time reaction monitoring has attracted tremendous interest in recent years. We have previously reported a reliable approach in which droplet spray ionization (DSI) was used for monitoring chemical reactions in real‐time. Herein, we systematically investigated the characterization and application of DSI for real‐time reaction monitoring.MethodsAnalyte ions are generated by loading a sample solution onto a corner of a microscope cover glass positioned in front of the MS inlet and applying a high voltage to the sample. The tolerance to positioning, solvent effect, spray angle and spray time were investigated. Extension to real‐time monitoring of macromolecule reactions was also demonstrated by the charge state change of cytochrome c in the presence of acetic acid.ResultsThe corner could be positioned within an area of approximately 10 × 6 × 5 mm (x, y, z) in front of the MS inlet. The broad polarities of solvents from methanol to PhF were suitable for DSI. It featured monitoring real‐time changes in reactions on the time scale of seconds to minutes. A real‐time charge state change of cytochrome c was captured.ConclusionsDSI‐MS features ease of use, durability of the spray platform and reusability of the ion source. Eliminating the need for a sample transport capillary, DSI opens a new avenue for the in situ analysis and real‐time monitoring of short‐lived key reaction intermediates even at subsecond dead times. Copyright © 2016 John Wiley & Sons, Ltd.
Proton and Hydride Transfer in the Skraup Reaction
Authors: Yamabe Shinichi , Yamazaki Shoko 
Published: August 2016

AbstractThe Skraup reaction affording quinoline was investigated computationally by the use of a model consisting of aniline, glycerol (HO‐CH2‐CH(OH)‐CH2OH) and H3O+ (H2O)7. First, two reaction channels up to the 1,2‐dihydroquinoline were considered. One is the traditional one involving acrolein. The other is for the direct linkage of aniline and glycerol. The channel without acrolein was calculated to be more likely. Second, the oxidation process of 1,2‐dihydroquinoline to quinoline was examined with and without the oxidizing agent, nitrobenzene. With it, the hydride‐shift path was obtained and it is likely energetically. Without it, while the process is feasible in accord with a microwave‐irradiation study, the large activation energy was required in the acid catalyzed either (1,2‐dihydroquinoline + glycerol) or (1,2‐dihydroquinoline + acrolein) reaction. The proton transfer was found to be primary driving force of the Skraup reaction.
Substrate Pre‐Folding and Water Molecule Organization Matters for Terpene Cyclase Catalyzed Conversion of Unnatural Substrates
Authors: Hammer Stephan C. , Syrén Per‐Olof , Hauer Bernhard 
Published: August 2016

AbstractTerpene cyclase enzymes have recently been challenged with terpene substrate derivatives to generate additional chemical complexity beyond to what is currently found in nature. Herein, molecular dynamics and biocatalysis are used to shed light on the flexibility and inherent limitation of a triterpene cyclase in converting unnatural substrates. Our studies suggest that populating binding modes which allows for concerted reaction pathways is a key element towards an expanded substrate scope and new chemistries displayed by terpene cyclases. Additionally, we show that the spatial organization of water, which is influenced by both the substrate architecture as well as the active site geometry, controls the product selectivity. This highlights that activity and selectivity displayed by terpene cyclases acting on unnatural substrates is particularly difficult to predict, since they depend on various parameters.
Combined ab initio and XPS Investigations of the Electronic Interactions of L–Cysteine Adsorbed on GaAs(1 0 0)
Authors: Juarez María F. , Toader Ana M. , Negrila Catalin , Santos Elizabeth , Lazarescu Valentina 
Published: August 2016

AbstractThe adsorption of L‐cysteine from ethanol solutions on GaAs(1 0 0) surfaces has been studied by XPS and density‐functional theory (DFT). XPS data reveal that the formation of the adsorbate involves preferentially the As‐sites for p‐GaAs(1 0 0) and the Ga‐sites for n‐GaAs(1 0 0). The adsorbed species show different orientations of the functional groups to the surface for the different substrates. DFT calculations performed for both Ga‐dimers and As‐dimers terminated surfaces show that the adsorption is energetically favourable on both substrates. However, the adsorption energy is more negative on top of Ga‐atoms. Here an important contribution for the stabilization of the adsorbate is the interaction of the functional groups with the surface. The parallel orientation found for the Ga‐bound species by DFT calculations is in good agreement with the shift in the binding energy of the NH2/NH3+ species observed by XPS analysis.
Architecture of Directed‐Channel Mesoporous Silica/Titania Shell on Bi‐Alkaline‐Earth Carbonate Particles for Core‐Shell Structure
Authors: Chen Xuncai , Kim Jinsoo , Jung Taesung , Park Jongho , Kim Woo‐Sik 
Published: August 2016

AbstractA generalized, single‐step synthetic method is outlined for the formation of directed‐channel mesoporous SiO2 or TiO2 shells on bi‐alkaline‐earth carbonate particles to create a core‐shell structure. Cetyltrimethylammonium bromide (CTAB) is used both as the structure‐directing template for the SiO2 and TiO2 shell layer during TEOS and TEOT hydrolysis/condensation and as the mesopore‐channel template in the shell. The resulting core‐shell particles display high properties for the specific surface area and pore volume. In addition, the reaction parameters for the formation of the SiO2 and TiO2 shell during the sol‐gel process are broadly investigated. Consequently, this directed mesoporous core‐shell structure can serve as a platform for further surface modifications to facilitate the rapid translation of particles to a wide range of end applications.
How entrepreneurs leverage institutional intermediaries in emerging economies to acquire public resources
Authors: Armanios Daniel Erian , Eesley Charles E. , Li Jizhen , Eisenhardt Kathleen M. 
Published: August 2016

Research summary: Governments in emerging economies often use institutional intermediaries to promote entrepreneurship, and bridge the void between ventures and public funding. While prior literature describes what institutional intermediaries do, it leaves open how intermediaries support different types of entrepreneurs. By comparing science park and non‐science park firms in Beijing and across China, we distinguish which entrepreneurs benefit from certification versus capability‐building through the introduction of two new constructs: skill adequacy and context relevance. Broadly, our study adds insights at the nexus of emerging economies and entrepreneurship research, and to the tie formation and institutional intermediaries literatures.Managerial summary: A key dilemma facing entrepreneurs is how to finance their ventures. While entrepreneurs in developed economies can seek VC or angel investment, entrepreneurs in emerging economies often need to pursue potential government funding opportunities. Our study highlights three strategies for acquiring government funding. Well‐connected entrepreneurs can leverage their political ties to acquire such funding. Less‐connected entrepreneurs can leverage science parks that in emerging markets are designed to help governments to identify promising ventures. For returnees whose ample experience abroad may not fit with local ways of doing business, gaining science park admission can certify quality and so ease the path to government funding. For technically skilled local entrepreneurs who lack business skills, science parks can help build such skills, which then ease the path to government funding. Copyright © 2016 John Wiley & Sons, Ltd.
Exposure to PM2.5 causes genetic changes in fetal rat cerebral cortex and hippocampus
Authors: Chao Ming‐Wei , Yang Chin‐Hua , Lin Po‐Ting , Yang Yu‐Hsiu , Chuang Yu‐Chen , Chung Meng‐Chi , Tseng Chia‐Yi 
Published: August 2016

ABSTRACTPM2.5 travels along the respiratory tract and enters systemic blood circulation. Studies have shown that PM2.5 increases the incidence of various diseases not only in adults but also in newborn infants. It causes chronic inflammation in pregnant women and retards fetal development. In this study, pregnant rats were exposed to PM2.5 for extended periods of time and it was found that PM2.5 exposure increased immune cells in mother rats. In addition, cytokines and free radicals rapidly accumulated in the amniotic fluid and indirectly affected the fetuses. The authors collected cerebral cortex and hippocampus samples at E18 and analyzed changes of miRNA levels. Expression levels of cortical miR‐6315, miR‐3588, and miR‐466b‐5p were upregulated, and positively correlated with the genes Pkn2 (astrocyte migration), Gorab (neuritogenesis), and Mobp (allergic encephalomyelitis). In contrast, PM2.5 decreased expression of miR‐338‐5p and let‐7e‐5p, both related to mental development. Further, PM2.5 exposure increased miR‐3560 and let‐7b‐5p in the hippocampus, two proteins that regulate genes Oxct1 and Lin28b that control ketogenesis and glycosylation, and neural cell differentiation, respectively. miR‐99b‐5p, miR‐92b‐5p, and miR‐99a‐5p were decreased, leading to reduced expression of Kbtbd8 and Adam11 which reduced cell mitosis, migration, and differentiation, and inhibited learning abilities and motor coordination of the fetus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1412–1425, 2017.
Echolocation in humans: an overview
Authors: Thaler Lore , Goodale Melvyn A. 
Published: August 2016

Bats and dolphins are known for their ability to use echolocation. They emit bursts of sounds and listen to the echoes that bounce back to detect the objects in their environment. What is not as well‐known is that some blind people have learned to do the same thing, making mouth clicks, for example, and using the returning echoes from those clicks to sense obstacles and objects of interest in their surroundings. The current review explores some of the research that has examined human echolocation and the changes that have been observed in the brains of echolocation experts. We also discuss potential applications and assistive technology based on echolocation. Blind echolocation experts can sense small differences in the location of objects, differentiate between objects of various sizes and shapes, and even between objects made of different materials, just by listening to the reflected echoes from mouth clicks. It is clear that echolocation may enable some blind people to do things that are otherwise thought to be impossible without vision, potentially providing them with a high degree of independence in their daily lives and demonstrating that echolocation can serve as an effective mobility strategy in the blind. Neuroimaging has shown that the processing of echoes activates brain regions in blind echolocators that would normally support vision in the sighted brain, and that the patterns of these activations are modulated by the information carried by the echoes. This work is shedding new light on just how plastic the human brain is. WIREs Cogn Sci 2016, 7:382‐393. doi: 10.1002/wcs.1408This article is categorized under:

Psychology > Brain Function and Dysfunction
Psychology > Perception and Psychophysics
Neuroscience > Plasticity
How Many Contralateral Carcinomas in Patients with Unilateral Papillary Thyroid Microcarcinoma are Preoperatively Misdiagnosed as Benign?
Authors: Wu Zeng Gui , Yan Xing Qiang , Su Ru Si , Ma Zhao Sheng , Xie Bo Jian , Cao Fei Lin 
Published: August 2016

AbstractBackgroundThe decision to perform a total thyroidectomy (TT) for unilateral papillary thyroid microcarcinoma (PTMC) with nodules in the contralateral lobe remains controversial. The aim of this study was to investigate the rate of contralateral carcinomas that are preoperatively misdiagnosed as benign.MethodsFrom October 2011 to October 2015, a total of 347 patients with unilateral PTMC and contralateral benign nodules who were treated with a TT at a single institution were enrolled. All patients underwent preoperative fine needle aspiration and ultrasonography (US). Clinicopathological features such as age, sex, laterality, tumor size, central lymph node metastases, capsular invasion, TgAb and TPOAb levels, Hashimoto’s thyroiditis, nodule number in both lobes according to preoperative US, and primary carcinoma number in the final postoperative pathology report were all analyzed to investigate the rate and predictive factors of contralateral carcinoma.ResultsA total of 100 patients (28.9 %) were diagnosed with papillary thyroid carcinoma in the contralateral lobe. A multivariate analysis showed that tumor size, nodule number in the contralateral lobe, and multifocality of the primary tumor were all independent predictive factors of contralateral carcinoma in patients with unilateral PTMC and contralateral benign nodules.ConclusionsAccording to our findings, the rate at which contralateral carcinomas are preoperatively misdiagnosed as benign is 28.9 %. A TT is essential for unilateral PTMC with a primary tumor size >5 mm, multifocal primary carcinomas or multifocal benign nodules in the contralateral lobe.
Evaluation of commercial soy sauce koji strains of Aspergillus oryzae for γ-aminobutyric acid (GABA) production
Authors: Ab Kadir Safuan , Wan-Mohtar Wan Abd Al Qadr Imad , Mohammad Rosfarizan , Abdul Halim Lim Sarina , Sabo Mohammed Abdulkarim , Saari Nazamid 
Published: August 2016

Abstract
In this study, four selected commercial strains of Aspergillus oryzae were collected from soy sauce koji. These A. oryzae strains designated as NSK, NSZ, NSJ and NST shared similar morphological characteristics with the reference strain (A. oryzae FRR 1675) which confirmed them as A. oryzae species. They were further evaluated for their ability to produce γ-aminobutyric acid (GABA) by cultivating the spore suspension in a broth medium containing 0.4 % (w/v) of glutamic acid as a substrate for GABA production. The results showed that these strains were capable of producing GABA; however, the concentrations differed significantly (P &lt; 0.05) among themselves. Based on the A. oryzae strains, highest GABA concentration was obtained from NSK (194 mg/L) followed by NSZ (63 mg/L), NSJ (51.53 mg/L) and NST (31.66 mg/L). Therefore, A. oryzae NSK was characterized and the sequence was found to be similar to A. oryzae and A. flavus with 99 % similarity. The evolutionary distance (K nuc) between sequences of identical fungal species was calculated and a phylogenetic tree prepared from the K nuc data showed that the isolate belonged to the A. oryzae species. This finding may allow the development of GABA-rich ingredients using A. oryzae NSK as a starter culture for soy sauce production.
Opportunities for Collaboration among East Asian and US Law Schools
Authors: SILVER Carole 
Published: August 2016

AbstractLaw schools in East Asia and the US share at least two central challenges. The first relates to globalization and the responsibility of law schools to prepare students to practise in a global environment. The second relates to the contest for control over lawyer licensing that law schools engage in with bar authorities, among others. Is either challenge appropriate for solution through a collaborative approach among law schools from different countries and regions? Research on collaboration identifies the need for a common, shared purpose among collaborators. Local differences make collaboration unlikely with regard to the contest for control, but the goal of developing an approach to prepare students for work in a global environment rises above national differences and is ripe for collaboration.
Modal Characteristics of Planar Multi-Story Frame Structures
Authors: Lin H.-P. , Chang S.-C. , Chu C. 
Published: August 2016

AbstractIn linear system, in-plane motions are decoupled from out-of-plane motions for planar frame structures. A theoretical method is proposed that permits the efficient calculations of modal characteristics of planar multi-story frame structures. There are 3 × m beam components for a planar m-story frame structure. By analyzing the transverse and longitudinal motions of each component simultaneously and considering the compatibility requirements across each frame joint, the undetermined variables of the entire m-story frame structure system can be reduced to six, regardless of the number of stories, and that can be determined by the application of the boundary conditions. The main feature of this method is to decrease the dimensions of the matrix involved in the finite element methods and certain other analytical methods.