bluuebunny/crossref_metadata_2025 huggingface dataset:
Fetal sex influence in the productive performance of dairy cows
Authors: Freitas Anielly De Paula , Gama Manuela Pires Monteiro da , Santos Guilherme Felipe Ferreira dos , Mendonça Gabriela Geraldi , Pereira Mariana Alencar , Vercesi Filho Aníbal Eugênio , Paz Claudia Cristina Paro de , Zadra Lenira El Faro
Published: September 2016

Investigating factors that could affect milk production of cows is an important way to improve the efficiency of production systems. This purpose of this study was to verify and quantify the influence of calf sex on milk production and lactation length in herds of Holstein, Gir, and Guzera cows. Data from 10,780 lactations of 4,807 Holstein cows that calved between 2001 and 2013; 18,898 lactations of 13,172 Gir cows that calved between 1985 and 2013; and 5,277 lactations of 3,972 Guzera cows that calved between 1987 and 2013 were used. Both the accumulated 305-day milk yield (P305) and the length of the lactation period up to 305 days (DL305) were evaluated. Analysis of variance was performed by the least squares method using the GLM procedure in the SAS statistical program. The P305 was not influenced by the sex of the calf in the Holstein breed. However in the zebu breeds (Gir and Guzera), both P305 and DL305 were significantly affected (P < 0.01) by the sex of the calf, with higher production and average length of lactation in cows that calved males. In addition, a significant difference was also nested within sex of calf and age at first calving (P < 0.05) in the Gir breed. The results indicate that for the zebu breeds, calf sex influences production characteristics.
An Analysis of Credibility of CEO’s in an Organisation Linkage with Employee Engagement
Authors: Sant Seema
Published: September 2016

The current study examines the credibility of the respective Chief Executive Officer (CEO’s) in an organization while linking its impacts with the concurrent facets of employee engagement. The credibility of a Chief Executive Officer (from now on referred to as the CEO) can greatly influence his/her employee's behaviour and perception towards the company’s objectives and reputation. A CEO with a credible reputation can help increase the productivity of workforce, the quality and quantity of leads, secure loyal customers, and help in retaining employees. The present study surveyed 186 employees randomly selected from the top 100 companies in India using the questionnaire developed by researcher to measure credibility of CEO linkage with employee engagement. Further the quantitative questionnaires collected from 186 employees were tabulated and analysed in order to study the linkage of the credibility of a CEO in an organization with the employee engagement and its effect on the organization's success. The result shows that the CEO's credibility is positively associated with employee engagement and subsequently affects the organizational reputation and success.
Determination of the Effectiveness of Neurofeedback on Reducing the Symptoms of Hyperactivity and Increasing the Accuracy and Caution in ADHD Children
Authors: Mohtashemi Masoomeh , Eftekharsaadi Zahra
Published: September 2016

This study is done to determine the effectiveness of Neurofeedback on reducing the symptoms of Hyperactivity and increasing the accuracy and caution in ADHD children. Subjects were 30 ADHD children who were selected by cluster sampling method. Research layout is pre-test, post-test experimental type. Conners parent measure questionnaire and a computer based continuous performance test are the research materials. The results of investigation on post-test average score of Hyperactivity symptoms and accuracy and caution of ADHD children in experimental and witness groups, with controlling of pre-test, has shown a significant difference.
The Marketing Stimuli Factors Influencing Consumers’ Attitudes to Purchase Organic Food
Authors: Bee Lian Song , Safari Meysam , Mansori Shaheen
Published: September 2016

The demand for organic food products have increased rapidly in recent years. Among the main factors contributed to the increasing global consumers’ demand towards organic food products are food safety concern, health benefits, better quality, higher nutritional value and environmental concern. Therefore, there is a need to explore consumers’ behaviour towards organic food products. This study attempts to examine the effects of marketing stimuli factors on consumers’ attitudes to purchase organic food in Malaysia. Five key marketing stimuli variables were examined in this study, and they were product attributes, price, availability, sales promotion and marketing communications. This study is based on the results of a survey conducted on a sample of 430 organic food consumers in Malaysia. The structural equation modelling was used for data analysis and six hypotheses were tested. The results showed that three marketing stimuli variables of product attributes, availability and sales promotion have significantly influenced consumers’ attitudes of organic food. Subsequently, consumers’ attitudes is positively correlated to actual purchase of organic food. There was no significant effect of price and marketing communications on consumers’ attitudes of organic food. Based on the findings, marketing stimuli strategies should be focused on creating positive attitude of consumers by increasing consumers’ awareness, trust, satisfaction and loyalty towards organic food. In addition, price of organic food should be reduced and more effective communication strategies should be undertaken to enhance consumers’ purchase of organic food.
Linking Psychological Empowerment to Job Satisfaction and Organizational Commitment: Investigating the Mediating Effect of Organizational Trust
Authors: Alajmi Sanad A.
Published: September 2016

The main purpose of this research is to examine the influence of psychological empowerment and organizational trust on job satisfaction and organizational commitment among Kuwait free trade zone employees. Data were obtained for this research through a set of questionnaire which was divided into four parts and administered to a total of 271 respondents. The results showed that psychological empowerment mainly affects employees’ job satisfaction and organizational commitment. The results indicated that two dimensions of psychological empowerment, i.e. Meaning and Impact, are significant and positively related to job satisfaction. The existing literature supports the relationships between psychological empowerment dimensions and three dimensions of organizational commitment: normative, continuance, and affective commitment. However, results from this study showed inconsistency. The results showed that only one dimension of Psychological Empowerment, Meaning, is significant and positively Associated to Affective Commitment; two dimensions of Psychological Empowerment, Meaning and Competence, are significant and positively Associated to Normative Commitment; and no dimensions of Psychological Empowerment are statistically contributed to Continuance Commitment.  Moreover, analysis has also showed that organizational trust mediates the relationships between psychological empowerment, job satisfaction and organizational commitment. Some practical implications are also discussed. The research concludes with limitations and future research suggestions to enhance psychological empowerment in public and private organizations in Kuwait.
The Balkan Area Development: Threats and Opportunities for Italian Companies’ Investment Strategies
Authors: Scalera Francesco
Published: September 2016

The globalisation of markets has called for, among others, two complementary requirements: on the one hand, the need to develop policies that are able to attract FDI (Foreign Direct Investment) by a number of transition economies, in order to boost the economic growth of the countries concerned and reduce the technological and socio-economic gap that separates them from the industrialised economies; on the other, the priority choice for companies to promote internationalisation, that is now considered as a necessary step to safeguard their competitiveness.

In particular, the analysis carried out starts with the evolution of the Balkan market, by collecting and describing  the macroeconomic data concerning the four Western Balkans countries (Albania, Macedonia, Montenegro, Serbia), representing those economies that are likely to join the EU in the coming years following the process started (official candidacy or accession negotiations).

Thus, the first part of the present paper aims at describing and analysing the operational and strategic behaviour of Italian companies, as well as their process of internationalisation in the abovementioned economies.

The analysis was carried out through submitting a questionnaire to managers and employees of companies operating in the Balkans; the results highlighted the main areas of the companies’ international management decision-making process (internationalisation decision, operating methods adopted and the results achieved).
Afterwards, the second part of the research sets the focus on the attractiveness degree reached in the area, following the reforms made by local governments that helped in improving the business climate, leading many Italian investors to operate in that area.
A Bayesian via Laplace Approximation on Log-gamma Model with Censored Data
Authors: Yusuf Madaki Umar , Abu Bakar Mohd Rizam , Husain Qasim Nasir , Ibrahim Noor Akma , Arasan Jayanthi
Published: September 2016

Log-gamma distribution is the extension of gamma distribution which is more flexible, versatile and provides a great fit to some skewed and censored data. Problem/Objective: In this paper we introduce a solution to closed forms of its survival function of the model which shows the suitability and flexibility towards modelling real life data. Methods/Analysis: Alternatively, Bayesian estimation by MCMC simulation using the Random-walk Metropolis algorithm was applied, using AIC and BIC comparison makes it the smallest and great choice for fitting the survival models and simulations by Markov Chain Monte Carlo Methods. Findings/Conclusion: It shows that this procedure and methods are better option in modelling Bayesian regression and survival/reliability analysis integrations in applied statistics, which based on the comparison criterion log-gamma model have the least values. However, the results of the censored data have been clarified with the simulation results.
Les disparus argentins de deuxième génération : vies paradoxales dans les limbes du social
Authors: Verstraeten Alice
Published: September 2016

Entre 1976 et 1983, la dictature militaire argentine fait disparaître 30 000 opposants. Ce crime contre l’humanité – reconnu comme tel depuis 2010 – est encore aggravé par les atteintes aux droits des enfants : 500 bébés sont « appropriés » par les militaires et leurs complices. Leurs identités sont effacées, de nouvelles filiations fictives sont créées.

Lorsque tombe la dictature en 1983, il est devenu évident que les adultes disparus qui n’ont pas été libérés des camps ont tous été assassinés. Leur disparition est une mort qui ne dit pas son nom, une mort en suspens. Les enfants, en revanche, restent des disparus vivants. Leur mort n’est pas en suspens. Leur vie, si. Leur vie est en suspens, et reste inextricablement liée, dans le réel comme dans le symbolique, à la mort de leurs parents. Je propose de me pencher sur l’espace-temps paradoxal que sont les « limbes du social » où sont confinés ces disparus. En les comprenant comme autant de « noeuds » de l’intime et du collectif, qui continuent de blesser, au présent, l’ensemble de la culture, nous interrogeons la possibilité de sortir de l’impasse symbolique – qui très vite devient une impasse politique. Nous défendons une éthique des vérités multiples, pour éclairer la nébuleuse de l’impunité.
Génocide contre les Tutsi du Rwanda : (sur)vivre avec la mort
Authors: Basabose Philippe
Published: September 2016

D’une part, cet article réfléchit sur la perception de la mort dans la société rwandaise et sur certaines des pratiques rituelles que cette perception commande. D’autre part, il examine les défis qu’a imposés à cet égard la catastrophe du génocide contre les Tutsi de 1994. Il conclut en posant quelques-unes des questions auxquelles toute tentative de sortie du cercle mortifère tracé par cette tragédie devra répondre.
Considérations juridiques et empiriques de l’application de la Loi concernant les soins de fin de vie en sphère clinique
Authors: Acem Elsa
Published: September 2016

Les conflits en sphère clinique sont souvent dus à une mauvaise communication entre soignants, patients, et leurs représentants. En l’absence d’une amélioration de ces relations, le nombre de discordes risque d’augmenter lors de l’administration de la sédation palliative continue et de l’aide médicale à mourir. Un examen de certaines études empiriques qui analysent la communication dans l’environnement médical, notamment pour ce qui a trait à l’obtention d’un consentement éclairé aux soins de fin de vie, ainsi que l’impact des différences culturelles et religieuses entre soignants et patients, permet d’identifier certaines pistes de solutions et d’effectuer une application de la Loi concernant les soins de fin de vie dans le respect des droits des patients.
Delaying precipitation by air pollution over the Pearl River Delta: 2. Model simulations
Authors: Lee Seoung Soo , Guo Jianping , Li Zhanqing
Published: September 2016

In Part 1 of two companion studies, analyses of observational data over the Pearl River Delta of China showed that larger aerosol concentrations (polluted conditions) resulted in suppressed precipitation before the midafternoon while resulting in enhanced precipitation after the midafternoon when compared to precipitation with smaller aerosol concentrations (clean conditions). This suggests that there is a tipping point in the transition from suppressing to enhancing precipitation with increases in aerosol concentration. This paper aims to identify mechanisms that control the tipping point by performing simulations. Simulations show that during the first three quarters of the 12 h simulation period, aerosol as a radiation absorber suppresses convection and precipitation by inducing greater radiative heating and stability. Convection weakens and precipitation reduces more under polluted conditions than under clean conditions. Due to the suppressed convection, the depletion of convective energy decreases. The reduced depletion of convective energy during the period of the suppressed convection boosts the level of stored energy after this period. The boosted level of stored energy enables updrafts to be strong enough to transport a greater amount of cloud liquid to the freezing level and to levels above it under polluted conditions than under clean conditions. This in turn induces greater freezing‐related latent heating, buoyancy, and thus stronger convection and results in the transition from lower precipitation rates during the first three quarters of the simulation period to higher precipitation rates during the last quarter of the period under polluted conditions than under clean conditions.
Slow slip hidden in the noise: The intermittence of tectonic release
Authors: Frank William B.
Published: September 2016

Referred to as slow slip events, the transient aseismic slip that occurs along plate boundaries can be indirectly characterized through colocated seismicity, such as tectonic tremor and low‐frequency earthquakes (LFEs). Using the timing of cataloged LFE and tremor activity in Guerrero, Mexico, and northern Cascadia, I decompose the interaseismic GPS displacement, defined as the surface deformation between previously detected slow slip events, into separate regimes of tectonic loading and release. In such a way, previously undetected slow slip events that produce less than a millimeter of surface deformation are extracted from the geodetic noise. These new observations demonstrate that the interaseismic period is not quiescent and that slow slip occurs much more often than previously thought. This suggests that the plate interface where slow slip and tremor occur is in fact strongly coupled and that slow aseismic release occurs over a wide spectrum of time scales.
Magnetic reconnection with a fast perpendicular sheared flow
Authors: Ma Xuanye , Otto Antonius , Delamere Peter A.
Published: September 2016

Magnetic reconnection at the Earth's low‐latitude magnetopause near the flank region is likely associated with a large sheared flow, being frequently quasi‐perpendicular to the antiparallel magnetic field components. The magnitude of a fast sheared flow can be super‐Alfvénic and even overcome the local fast mode speed. A scaling analysis implies a contradiction between the Walén relation and the balance of the total pressure for magnetic reconnection with a supercritical perpendicular sheared flow. This study uses one‐ and two‐dimensional magnetohydrodynamic (MHD) simulations to demonstrate that the traditional reconnection layer violates the Walén relation but still maintains the total pressure balance in such a configuration. The results show an expanded outflow region, consistent with the presence of divergent normal flow, and a significant decrease of the plasma density as well as the thermal pressure in the outflow region. In contrast, the magnitude of the magnetic field in the outflow region matches the value in the inflow region due to the total pressure balance, which is fundamentally different from the classical reconnection layer under sub‐Alfvénic perpendicular sheared flow conditions. In three‐dimensional geometry, the fast sheared flow without being stabilized by the magnetic field is expected to be Kelvin‐Helmholtz unstable. However, the three‐dimensional MHD simulation suggests that such structure can be KH stable. Although, the presence of surface waves modulates some two‐dimensional features, the major characteristics of the expanded outflow region are likely to be observed by in situ satellites.
The sustainability of habitability on terrestrial planets: Insights, questions, and needed measurements from Mars for understanding the evolution of Earth‐like worlds
Authors: Ehlmann B. L. , Anderson F. S. , Andrews‐Hanna J. , Catling D. C. , Christensen P. R. , Cohen B. A. , Dressing C. D. , Edwards C. S. , Elkins‐Tanton L. T. , Farley K. A. , Fassett C. I. , Fischer W. W. , Fraeman A. A. , Golombek M. P. , Hamilton V. E. , Hayes A. G. , Herd C. D. K. , Horgan B. , Hu R. , Jakosky B. M. , Johnson J. R. , Kasting J. F. , Kerber L. , Kinch K. M. , Kite E. S. , Knutson H. A. , Lunine J. I. , Mahaffy P. R. , Mangold N. , McCubbin F. M. , Mustard J. F. , Niles P. B. , Quantin‐Nataf C. , Rice M. S. , Stack K. M. , Stevenson D. J. , Stewart S. T. , Toplis M. J. , Usui T. , Weiss B. P. , Werner S. C. , Wordsworth R. D. , Wray J. J. , Yingst R. A. , Yung Y. L. , Zahnle K. J.
Published: September 2016

What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial‐type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar system's longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher‐resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to understanding the factors driving the divergent evolutionary paths of the Earth, Venus, and thousands of small rocky extrasolar planets yet to be discovered.
Microwave Plasma Systems in Optical and Mass Spectroscopy
Authors: Jankowski Krzysztof J. , Reszke Edward , Broekaert Jose A.C.
Published: September 2016

The art and science of microwave plasma (MWP) optical and mass spectroscopy is briefly presented including very recent advances in the field up to 2015. The use of MWPs as radiation sources for optical emission (OES) and atomic fluorescence (AFS) spectroscopy and as atom reservoirs for atomic absorption (AAS) and cavity ringdown (CRDS) spectroscopy as well as ion sources for both elemental and molecular mass spectrometry (MS) is treated.

Devices for producing both E‐type capacitively coupled microwave plasma (CMP)‐electrode and microwave‐induced plasma (MIP)‐electrodeless MWPs, including ICP‐like H‐type plasmas, are classified and discussed, in addition to techniques of their diagnostics, and results for the analytically relevant plasma parameters are presented. The means of generation of voluminous symmetrical plasmas and uses of microplasma devices are also presented with an effort to comment on general classification of microwave cavities. Further, the use of microwaves for boosting of glow discharges (GDs) and laser‐induced plasmas (LIBS) is treated along with other tandem sources. Methods for introduction of gaseous, liquid, and solid samples into the MWP are discussed. They include direct vapor sampling (DVS), chemical vapor generation (CVG) and hydride generation (HG) techniques, dry aerosol generation techniques (electrothermal vaporization (ETV), spark (SA) and laser ablation (LA) and continuous powder introduction (CPI)), and wet aerosol generation techniques using both solution and slurry nebulization. Special reference is made to coupling with gas chromatography (GC) and also with various separation techniques for liquids including high‐performance liquid chromatography (HPLC), supercritical fluid chromatography (SFC), and size‐exclusion chromatography (SEC). The analytical figures of merit in the case of OES with MIPs, CMPs, microwave plasma torch (MPT), MWP‐electrode sources including rotating‐field‐sustained plasma, and H‐type MWP as well as microplasmas are given. There are also described cases of atomic absorption and fluorescence with these sources. The developments in both elemental and molecular MS in the case of both cold and hot MWPs and in the case of various types of sample introduction techniques are discussed.

Applications of MWP analytical spectroscopy are in the fields of biological, clinical, environmental, and industrial samples with special reference to multielement analysis, element speciation, on‐line monitoring, particle sizing, and direct solids analysis. A critical comparison of the methodology with other spectroscopic methods for the determination of the elements and their species is given.
Multivariate and Hyperspectral Image Analysis
Authors: Grahn Hans F. , Geladi Paul , Esbensen Kim H.
Published: September 2016

Hyperspectral analysis is an imaging and an analytical technique. The simplest hyperspectral images are of the typex‐coordinate ×y‐coordinate × variable and these can become huge in size, requiring special considerations for storage and analysis. The article gives a general introduction to the importance of imaging in the sciences, followed by definitions and ways of creating hyperspectral images for both planar and volume images. A number of techniques for creating variables are summed up and a didactical example is given of how an analysis would take place in different systematic steps. The example gives special emphasis on the visual‐interactive interpretation. The article is supplemented by numerous general literature references.
Chemometrics in Bioanalytical Chemistry
Authors: Wu Hai‐Long , Yin Xiao‐Li , Gu Hui‐Wen , Xie Li‐Xia , Yu Ru‐Qin
Published: September 2016

Chemometrics, as a young science in chemical discipline, has been widely applied in many fields, such as environmental, clinical and forensic, food, industrial, biological, theoretical, and physical sciences. With the advent of postgenomic era, a powerful tool was urgently needed to extract useful chemical information from huge biological data, which results in the development and application of chemometrics in bioanalytical chemistry. At present, the application of chemometrics in bioanalytical chemistry mainly involves in quantitative bioanalysis and ‘‐omics’. This article focuses on multivariate and multiway calibration in quantitative bioanalysis, which covers fundamentals, current situations, innovative applications, and research trends of these chemometric methods.
A Phenomenological Model of Twinning Kinetics
Authors: Vinogradov Alexei , Vasilev Evgeny , Merson Dmitry , Estrin Yuri
Published: September 2016

We present a model of deformation twinning based on the idea that twin generation is a stress‐driven process. Using simple, yet sensible, assumptions regarding the grain size distribution, an equation for the variation of the twin volume fraction with the flow stress is obtained. The model is validated for the case of Mg alloy ZK60 through measurements of the evolving volume fraction of twins by means of direct video observation of the specimen surface and by monitoring the acoustic emission signals.
Mechanically Robust Silver Nanowires Network for Triboelectric Nanogenerators
Authors: Kang Hyungseok , Kim Han , Kim Seongsu , Shin Hyeon Jin , Cheon Siuk , Huh Ji‐Hyeok , Lee Dong Yun , Lee Seungwoo , Kim Sang‐Woo , Cho Jeong Ho
Published: September 2016

The authors develop a mechanically robust silver nanowires (AgNWs) electrode platform for use in flexible and stretchable triboelectric nanogenerators (TENGs). The embedding of an AgNWs network into a photocurable or thermocurable polymeric matrix dramatically enhances the mechanical robustness of the flexible and stretchable TENG electrodes while maintaining a highly efficient triboelectric performance. The AgNWs/polymeric matrix electrode is fabricated in four steps: (i) the AgNWs networks are formed on a hydrophobic glass substrate; (ii) a laminating photocurable or thermocurable prepolymer film is applied to the developed AgNWs network; (iii) the polymeric matrix is crosslinked by UV exposure or thermal treatment; and (iv) the AgNWs‐embedded polymeric matrix is delaminated from the glass substrate. The AgNWs‐embedded polymeric matrix electrodes with four different sheet resistances, controlled by varying the AgNWs network deposition density, are deployed in TENG devices. The authors find that the potential difference between the two contact surfaces of the AgNWs network‐embedded polymer matrix electrodes and the nylon (or perfluoroalkoxy alkane) governs the output triboelectric performances of the devices, rather than the sheet resistance. Both Kelvin probe force microscopy and numerical simulations strongly support these observations.
Highly Efficient, Mechanically Flexible, Semi‐Transparent Organic Solar Cells Doctor Bladed from Non‐Halogenated Solvents
Authors: Czolk Jens , Landerer Dominik , Koppitz Manuel , Nass David , Colsmann Alexander
Published: September 2016

All‐solution deposited, ITO‐free organic solar cells comprising hybrid top and bottom electrodes and ternary polymer:fullerene photo‐active layers are investigated. A printed micro silver mesh and conductive PEDOT:PSS are employed as bottom electrode on a mechanically flexible PET substrate, whereas the top electrode features highly conductive PEDOT:PSS with dispersed silver nanowires. The highly efficient ternary polymer:fullerene absorber blend PffBT4T‐2OD:PC61BM:PC71BM and all other functional layers are doctor bladed from non‐halogenated solvents in order to comply with the requirements of industrial device fabrication. The semi‐transparent solar cells yield maximum power conversion efficiencies of 6.6% on active areas ≤ 0.1 cm2 and 5.9% on active areas > 1 cm2. Omitting additional bus bars for charge extraction grants the solar cells a homogeneous appearance and transparency perception.
Direct and Stereoselective Synthesis of Diversely Substituted 2,4‐trans‐(NH)‐Pyrrolidines by Copper(I)‐Catalyzed Radical Cyclization at Low Temperature
Authors: Ram Ram N. , Gupta Dharmendra Kumar
Published: September 2016

This work describes a successful copper(I)‐catalyzed radical cyclization of β‐haloethylallylamines bearing an unprotected NH‐group while retaining catalyst‐redox activity. The cyclization occurs regio‐ and diastereoselectively at 0 °C and furnishes diversely substituted 1,3‐trans‐(NH)‐pyrrolidines directly in high isolated yields. An involvement of the bulky copper complex in the cyclization step as the possible reason for the diastereoselectivity was proposed. Synthetic applications of the products in the preparation of useful 4‐chloro‐NH‐pyrrole in a single step, has also been demonstrated. A quick, mild and general method involving simple addition of trichloroacetic acid/dimethyl sulfoxide (CCl3CO2H‐DMSO) solution to readily accessible N‐allylaldimines and ketimines tolerating acid‐sensitive and highly deactivating substituents was developed to access the amine precursors.

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Comprehensive Writing Margin Analysis and its Application to Stacked one Diode‐One Memory Device for High‐Density Crossbar Resistance Switching Random Access Memory
Authors: Yoon Kyung Jean , Bae Woorham , Jeong Deog‐Kyoon , Hwang Cheol Seong
Published: September 2016

The sneak current through the neighboring cells interrupts reading of a selected cell in high‐resistance state in crossbar resistance switching random access memory (RRAM). As the sneak current mainly originates from a parallel resistance component to a selected cell, write operation, which requires sufficiently high voltage delivered to the selected cell, has been regarded to have little relevance to the sneak current issue. In this work, it is revealed that an additional voltage drop on the wire resistances of selected word and bit lines causes an increase in voltage for the write operation (programming/erasing), whose degree is associated with the selectivity of the RRAM selector, array size, resistance of the selected cell, and wire resistances. The presence of sneak paths gives rise to an additional concern about the disturbance of the unselected cells, especially when the writing voltage of the selected cell was increased by the aforementioned factors. A floating voltage scheme is considered for proposing a unified writing margin analysis model with diode selectors, and a feasible design strategy based on the analysis for an experimental RRAM device employing a diode with an extremely high rectification ratio (8.4 × 108) is provided. Furthermore, application of the model to the universal RRAM devices, irrespective of their switching polarity, selector types, and adopted voltage schemes, is included.
Environmentally Friendly Hydrogel‐Based Triboelectric Nanogenerators for Versatile Energy Harvesting and Self‐Powered Sensors
Authors: Xu Wei , Huang Long‐Biao , Wong Man‐Chung , Chen Li , Bai Gongxun , Hao Jianhua
Published: September 2016

Triboelectric nanogenerators (TENGs), as a promising energy harvesting technology, have been rapidly developed in recent years. However, the research based on fully flexible and environmentally friendly TENGs is still limited. Herein, for the first time, a hydrogel‐based triboelectric nanogenerator (Hydrogel‐TENG) with high flexibility, recyclability, and environmental friendliness simultaneously has been demonstrated. The standard Hydrogel‐TENG can generate a maximum output power of 2 mW at a load resistance of 10 MΩ. The tube‐shaped Hydrogel‐TENG can harvest mechanical energy from various human motions, including bending, twisting, and stretching. Furthermore, the system can serve as self‐powered sensors to detect the human motions. Additionally, the utilized Polyvinyl Alcohol hydrogel employed in this study is recyclable to benefit for fabricating the renewable TENG. The open‐circuit voltage of renewed hydrogel‐TENG can reach up to 92% of the pristine output voltage. This research will pave a potential approach for the development of flexible energy sources and self‐powered motion sensors in environmentally friendly way.
Spatial and temporal scaling of unequal microbubble coalescence
Authors: Chen Rou , Yu Huidan (Whitney) , Zhu Likun , Patil Raveena M. , Lee Taehun
Published: September 2016

We numerically study coalescence of air microbubbles in water, with density ratio 833 and viscosity ratio 50.5, using lattice Boltzmann method. The focus is on the effects of size inequality of parent bubbles on the interfacial dynamics and coalescence time. Twelve cases, varying the size ratio of large to small parent bubble from 5.33 to 1, are systematically investigated. The “coalescence preference,” coalesced bubble closer to the larger parent bubble, is well observed and the captured power‐law relation between the preferential relative distance χ and size inequality γ,
, is consistent to the recent experimental observations. Meanwhile, the coalescence time also exhibits power‐law scaling as
, indicating that unequal bubbles coalesce faster than equal bubbles. Such a temporal scaling of coalescence on size inequality is believed to be the first‐time observation as the fast coalescence of microbubbles is generally hard to be recorded through laboratory experimentation. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1441–1450, 2017
Wear and its effects on dental topography measures in howling monkeys (Alouatta palliata)
Authors: Pampush James D. , Spradley Jackson P. , Morse Paul E. , Harrington Arianna R. , Allen Kari L. , Boyer Doug M. , Kay Richard F.
Published: September 2016

Objectives

Three dental topography measurements: Dirichlet Normal Energy (DNE), Relief Index (RFI), and Orientation Patch Count Rotated (OPCR) are examined for their interaction with measures of wear, within and between upper and lower molars inAlouatta palliata. Potential inferences of the “dental sculpting” phenomenon are explored.

Materials and methods

Fifteen occluding pairs of howling monkey first molars (15 upper, 15 lower) opportunistically collected from La Pacifica, Costa Rica, were selected to sample wear stages ranging from unworn to heavily worn as measured by the Dentine Exposure Ratio (DER). DNE, RFI, and OPCR were measured from three‐dimensional surface reconstructions (PLY files) derived from high‐resolution CT scans. Relationships among the variables were tested with regression analyses.

Results

Upper molars have more cutting edges, exhibiting significantly higher DNE, but have significantly lower RFI values. However, the relationships among the measures are concordant across both sets of molars. DER and EDJL are curvilinearly related. DER is positively correlated with DNE, negatively correlated with RFI, and uncorrelated with OPCR. EDJL is not correlated with DNE, or RFI, but is positively correlated with OPCR among lower molars only.

Discussion

The relationships among these metrics suggest that howling monkey teeth adaptively engage macrowear. DNE increases with wear in this sample presumably improving food breakdown. RFI is initially high but declines with wear, suggesting that the initially high RFI safeguards against dental senescence. OPCR values in howling monkey teeth do not show a clear relationship with wear changes.
Rapid Photoactivated Generation of Nitroxyl (HNO) under Neutral pH Conditions
Authors: Zhou Yang , Cink Ruth B. , Dassanayake Rohan S. , Seed Alexander J. , Brasch Nicola E. , Sampson Paul
Published: September 2016

Directly obtaining kinetic and mechanistic data for the reactions of nitroxyl (HNO) with biomolecules (k≈103–107 m−1 s−1) is not feasible for many systems because of slow HNO release from HNO donor molecules (t1/2 is typically minutes to hours). To address this limitation, we have developed a photoactivatable HNO donor incorporating the (3‐hydroxy‐2‐naphthalenyl)methyl phototrigger, which rapidly releases HNO on demand. A “proof of concept” study is reported, which demonstrates that, upon continuous xenon light excitation, rapid decomposition of the HNO donor occurs within seconds. The amount of HNO generated is strongly dependent on solvent and the rate of the reaction is dependent on the light intensity.
Covalent Assembly and Characterization of Nonsymmetrical Single‐Molecule Nodes
Authors: Nacci Christophe , Viertel Andreas , Hecht Stefan , Grill Leonhard
Published: September 2016

The covalent linking of molecular building blocks on surfaces enables the construction of specific molecular nanostructures of well‐defined shape. Molecular nodes linked to various entities play a key role in such networks, but represent a particular challenge because they require a well‐defined arrangement of different building blocks. Herein, we describe the construction of a chemically and geometrically well defined covalent architecture made of one central node and three molecular wires arranged in a nonsymmetrical way and thus encoding different conjugation pathways. Very different architectures of either very limited or rather extended size were obtained depending on the building blocks used for the covalent linking process on the Au(111) surface. Electrical measurements were carried out by pulling individual molecular nodes with the tip of a scanning tunneling microscope. The results of this challenging procedure indicate subtle differences if the nodes are contacted at inequivalent termini.
Use of an Octapeptide–Guanidiniocarbonylpyrrole Conjugate for the Formation of a Supramolecular β‐Helix that Self‐Assembles into pH‐Responsive Fibers
Authors: Li Mao , Radić Stojković Marijana , Ehlers Martin , Zellermann Elio , Piantanida Ivo , Schmuck Carsten
Published: September 2016

Peptides that adopt β‐helix structures are predominantly found in transmembrane protein domains or in the lipid bilayer of vesicles. Constructing a β‐helix structure in pure water has been considered difficult without the addition of membrane mimics. Herein, we report such an example; peptide 1 self‐assembles into a supramolecular β‐helix in pure water based on charge interactions between the individual peptides. Peptide 1 further showed intriguing transitions from small particles to helical fibers in a time‐dependent process. The fibers can be switched to vesicles by changing the pH value.
Self‐Healing Molecular Crystals
Authors: Commins Patrick , Hara Hideyuki , Naumov Panče
Published: September 2016

One of the most inevitable limitations of any material that is exposed to mechanical impact is that they are inexorably prone to mechanical damage, such as cracking, denting, gouging, or wearing. To confront this challenge, the field of polymers has developed materials that are capable of autonomous self‐healing and recover their macroscopic integrity similar to biological organisms. However, the study of this phenomenon has mostly remained within the soft materials community and has not been explored by solid‐state organic chemists. The first evidence of self‐healing in a molecular crystal is now presented using crystals of dipyrazolethiuram disulfide. The crystals were mildly compressed and the degree of healing was found to be 6.7 %. These findings show that the self‐healing properties can be extended beyond mesophasic materials and applied towards the realm of ordered solid‐state compounds.
A Three‐Dimensional Origami Paper‐Based Device for Potentiometric Biosensing
Authors: Ding Jiawang , Li Bowei , Chen Lingxin , Qin Wei
Published: September 2016

Current paper‐based potentiometric ion‐sensing platforms are planar devices used for clinically relevant ions. These devices, however, have not been designed for the potentiometric biosensing of proteins or small molecule analytes. A three‐dimensional origami paper‐based device, in which a solid‐contact ion‐selective electrode is integrated with an all‐solid‐state reference electrode, is described for the first time. The device is made by impregnation of paper with appropriate bioreceptors and reporting reagents on different zones. By folding and unfolding the paper structures, versatile potentiometric bioassays can be performed. A USB‐controlled miniaturized electrochemical detector can be used for simple and in situ measurements. Using butyrylcholinesterase as a model enzyme, the device has been successfully applied to the detection of enzyme activities and organophosphate pesticides involved in the enzymatic system as inhibitors. The proposed 3D origami paper device allows the potentiometric biosensing of proteins and small molecules in a simple, portable, and cost‐effective way.
Pictet–Spengler Synthesis of Quinoline‐Fused Porphyrins and Phenanthroline‐Fused Diporphyrins
Authors: Gao Ke , Fukui Norihito , Jung Seok II , Yorimitsu Hideki , Kim Dongho , Osuka Atsuhiro
Published: September 2016

Doubly and quadruply quinoline‐fused porphyrins were effectively synthesized through a reaction sequence consisting of Suzuki–Miyaura coupling of β‐borylated porphyrins with 2‐iodoaniline and subsequent Pictet–Spengler cyclization. These quinoline‐fused porphyrins display red‐shifted absorption bands and higher electron‐accepting abilities. This synthetic protocol also allowed the synthesis of phenanthroline‐fused porphyrin dimers, which bound either a NiII or ZnII cation. The resultant metal complexes displayed further red shifted absorption spectra and molecular twists to effect an almost perpendicular arrangement of the two porphyrins.
Switching on Supramolecular Catalysis via Cavity Mediation and Electrostatic Regulation
Authors: Qiao Yupu , Zhang Long , Li Jia , Lin Wei , Wang Zhenqiang
Published: September 2016

Synthetic supercontainers constructed from divalent metal ions, carboxylate linkers, and sulfonylcalix[4]arene‐based container precursors exhibit great promise as enzyme mimics that function in organic solvents. The capacity of these artificial hosts to catalyze Knoevenagel condensation can be switched on when the aldehyde substrate possesses a molecular size and shape matching the nanocavity of the supercontainers. In contrast, little reactivity is observed for other aldehydes that do not match the binding pocket. This substrate‐dependent catalytic selectivity is attributed to the Brønsted acidity of the metal‐bound water molecules located inside the nanocavity, which is amplified when the size/shape of the aldehyde substrate fits the binding cavity. The electrostatic environment of the binding cavity and the Brønsted acidity of the supercontainer can be further modulated using tetraalkylammonium‐based regulators, leading to higher reactivity for the otherwise unreactive aldehydes.
Frequency‐Driven Self‐Organized Helical Superstructures Loaded with Mesogen‐Grafted Silica Nanoparticles
Authors: Gutierrez‐Cuevas Karla G. , Wang Ling , Zheng Zhi‐gang , Bisoyi Hari K. , Li Guoqiang , Tan Loon‐Seng , Vaia Richard A. , Li Quan
Published: September 2016

Adding colloidal nanoparticles into liquid‐crystal media has become a promising pathway either to enhance or to introduce novel properties for improved device performance. Here we designed and synthesized new colloidal hybrid silica nanoparticles passivated with a mesogenic monolayer on the surface to facilitate their organo‐solubility and compatibility in a liquid‐crystal host. The resulting nanoparticles were identified by 1H NMR spectroscopy, TEM, TGA, and UV/Vis techniques, and the hybrid nanoparticles were doped into a dual‐frequency cholesteric liquid‐crystal host to appraise both their compatibility with the host and the effect of the doping concentration on their electro‐optical properties. Interestingly, the silica‐nanoparticle‐doped liquid‐crystalline nanocomposites were found to be able to dynamically self‐organize into a helical configuration and exhibit multi‐stability, that is, homeotropic (transparent), focal conic (opaque), and planar states (partially transparent), depending on the frequency applied at sustained low voltage. Significantly, a higher contrast ratio between the transparent state and scattering state was accomplished in the nanoparticle‐embedded liquid‐crystal systems.
Giant Hysteretic Sorption of CO2: In Situ Crystallographic Visualization of Guest Binding within a Breathing Framework at 298 K
Authors: Lama Prem , Aggarwal Himanshu , Bezuidenhout Charl X. , Barbour Leonard J.
Published: September 2016

A dynamic ZnII‐MOF has been shown to exhibit extreme breathing behavior under gas pressure. The very narrow pore form of the activated framework opens up in the presence of carbon dioxide, thus making it a suitable material for CO2 capture. Sorption of CO2 at 298 K and relatively high pressure clearly shows a two‐step isotherm with giant hysteresis for the second step. In‐situ single‐crystal diffraction analysis was carried out under CO2 gas pressure at 298 K using an environmental gas cell in order to visualize the interaction between CO2 and the host framework. The results are well supported by pressure‐gradient differential scanning calorimetry (P‐DSC) and variable‐pressure powder X‐ray analysis. Theoretical calculations have been carried out in order to further back up the crystallographic data.
Stereoselective Organocatalyzed Synthesis of α‐Fluorinated β‐Amino Thioesters and Their Application in Peptide Synthesis
Authors: Cosimi Elena , Engl Oliver D. , Saadi Jakub , Ebert Marc‐Olivier , Wennemers Helma
Published: September 2016

α‐Fluorinated β‐amino thioesters were obtained in high yields and stereoselectivities by organocatalyzed addition reactions of α‐fluorinated monothiomalonates (F‐MTMs) to N‐Cbz‐ and N‐Boc‐protected imines. The transformation requires catalyst loadings of only 1 mol % and proceeds under mild reaction conditions. The obtained addition products were readily used for coupling‐reagent‐free peptide synthesis in solution and on solid phase. The α‐fluoro‐β‐(carb)amido moiety showed distinct conformational preferences, as determined by crystal structure and NMR spectroscopic analysis.
One‐Pot Three‐Component Synthesis of Vicinal Diamines via In Situ Aminal Formation and Carboamination
Authors: Orcel Ugo , Waser Jerome
Published: September 2016

A synthesis of vicinal diamines via in situ aminal formation and carboamination of allyl amines is reported. Employing highly electron‐poor trifluoromethyl aldimines in their stable hemiaminal form was key to enable both a fast and complete aminal formation as well as the palladium‐catalyzed carboamination step. The conditions developed allow the introduction of a wide variety of alkynyl, vinyl, aryl, and hetereoaryl groups with complete regioselectivity and high diastereoselectivity. The reaction exhibits a high functional‐group tolerance. Importantly, either nitrogen atom of the imidazolidine products can be selectively deprotected, while removal of the aminal tether can be achieved in a single step under mild conditions to reveal the free diamine. We expect that this work will promote the further use of mixed aminal tethers in organic synthesis.