bluuebunny/crossref_metadata_2025_split huggingface dataset:
Colonialismo português e resistências angolanas nas memórias de Adriano João Sebastião (1923-1960)
Authors: Nascimento Washington Santos 
Published: December 2016

Este artigo faz uma discussão sobre a maior presença do colonialismo português no interior angolano na primeira metade do século XX e as resistências a ele. Para tanto, acompanharemos parte da vida do politico Adriano João Sebastião desde o seu nascimento, em 1923, até sua prisão, em 1960, através da análise de seu livro de memórias “Dos Campos de Algodão aos dias de hoje”, editado em 1993. Pretende-se, desta forma, entender como o colonialismo português afetou o cotidiano de um homem angolano. Palavras-chave: Angola, Colonização, Resistências; Adriano Sebastião; Memórias.
High-speed solar-blind UV photodetectors using high-Al content Al0.64Ga0.36N/Al0.34Ga0.66N multiple quantum wells
Authors: Muhtadi Sakib , Hwang Seong Mo , Coleman Antwon L. , Lunev Alexander , Asif Fatima , Chava V. S. N. , Chandrashekhar M. V. S. , Khan Asif 
Published: December 2016

Abstract
We demonstrate high-external quantum efficiency (∼50%) solar-blind AlGaN p–n junction photodetectors with high-Al content multiple quantum wells (MQWs). A peak responsivity of 0.1 A/W at 250 nm, which falls >103 by 280 nm, indicates that the optical absorption is dominated by the MQW structures. At a reverse bias of 0.5 V, the dark current is <0.1 pA. The readout RC-limited time response is measured as 0.4 µs, and an achievable detector RC-limited time response of 2 ns is estimated. The devices do not show internal gain, which accounts for their high speed.
Light emission from an m-plane n-ZnO/p-Si heterojunction with an AlN interlayer
Authors: Chen Chao , Wang Ti , Xu Yang , Ai Zhiwei 
Published: December 2016

Abstract
Nonpolar m-plane n-ZnO/p-Si heterojunction light-emitting devices with and without an AlN intermediate layer were fabricated by atomic layer deposition. The energy band alignment of the ZnO/AlN/Si heterostructure was studied using X-ray photoelectron spectroscopy, and the result confirmed the electron-blocking ability of the AlN interlayer. Electroluminescence results revealed that the devices with the AlN intermediate layer emit a quasi-white light. This work indicates that the AlN intermediate layer can effectively improve the performance of n-ZnO/p-Si heterojunction light-emitting devices.
Hairiness: the missing link between pollinators and pollination
Authors: Stavert Jamie R. , Liñán-Cembrano Gustavo , Beggs Jacqueline R. , Howlett Brad G. , Pattemore David E. , Bartomeus Ignasi 
Published: December 2016

BackgroundFunctional traits are the primary biotic component driving organism influence on ecosystem functions; in consequence, traits are widely used in ecological research. However, most animal trait-based studies use easy-to-measure characteristics of species that are at best only weakly associated with functions. Animal-mediated pollination is a key ecosystem function and is likely to be influenced by pollinator traits, but to date no one has identified functional traits that are simple to measure and have good predictive power.MethodsHere, we show that a simple, easy to measure trait (hairiness) can predict pollinator effectiveness with high accuracy. We used a novel image analysis method to calculate entropy values for insect body surfaces as a measure of hairiness. We evaluated the power of our method for predicting pollinator effectiveness by regressing pollinator hairiness (entropy) against single visit pollen deposition (SVD) and pollen loads on insects. We used linear models and AICCmodel selection to determine which body regions were the best predictors of SVD and pollen load.ResultsWe found that hairiness can be used as a robust proxy of SVD. The best models for predicting SVD for the flower speciesBrassica rapaandActinidia deliciosawere hairiness on the face and thorax as predictors (R2 = 0.98 and 0.91 respectively). The best model for predicting pollen load forB.rapawas hairiness on the face (R2 = 0.81).DiscussionWe suggest that the match between pollinator body region hairiness and plant reproductive structure morphology is a powerful predictor of pollinator effectiveness. We show that pollinator hairiness is strongly linked to pollination—an important ecosystem function, and provide a rigorous and time-efficient method for measuring hairiness. Identifying and accurately measuring key traits that drive ecosystem processes is critical as global change increasingly alters ecological communities, and subsequently, ecosystem functions worldwide.
Candidate pathogenicity islands in the genome of ‘CandidatusRickettsiella isopodorum’, an intracellular bacterium infecting terrestrial isopod crustaceans
Authors: Wang YaDong , Chandler Christopher 
Published: December 2016

The bacterial genusRickettsiellabelongs to the order Legionellales in the Gammaproteobacteria, and consists of several described species and pathotypes, most of which are considered to be intracellular pathogens infecting arthropods. Two members of this genus,R. grylliandR. isopodorum, are known to infect terrestrial isopod crustaceans. In this study, we assembled a draft genomic sequence forR. isopodorum, and performed a comparative genomic analysis withR. grylli. We found evidence for several candidate genomic island regions inR. isopodorum, none of which appear in the previously availableR. grylligenome sequence.Furthermore, one of these genomic island candidates inR. isopodorumcontained a gene that encodes a cytotoxin partially homologous to those found inPhotorhabdus luminescensandXenorhabdus nematophilus(Enterobacteriaceae), suggesting that horizontal gene transfer may have played a role in the evolution of pathogenicity inRickettsiella. These results lay the groundwork for future studies on the mechanisms underlying pathogenesis inR. isopodorum, and this system may provide a good model for studying the evolution of host-microbe interactions in nature.
Partitioning of crustal shortening during continental collision: 2‐D thermomechanical modeling
Authors: Liao Jie , Gerya Taras 
Published: December 2016

AbstractPartitioning of crustal shortening between the colliding continental plates is highly variable in nature. Physical controls of such variability remain largely enigmatic and require quantitative understanding. In this study, we employ 2‐D thermomechanical numerical modeling to investigate the influence of the rheological properties of the continental crust on the dynamics and distribution of crustal shortening during continental collision. Three major physical parameters, (i) the mechanical strength of the upper crust, (ii) the Moho temperature, and (iii) the convergence rate, are investigated, and their influences on crustal shortening partitioning between the lower and upper plates are systematically documented. Numerical modeling results suggest that a strong upper crust of the lower plate, high Moho temperature, and slow convergence rate favor migration of crustal shortening from the lower to the upper plate. Our numerical modeling results compare well with natural observations from the Alpine orogenic system where variable partitioning of crustal deformation between the plates is documented.
A comparison of the climates of the Medieval Climate Anomaly, Little Ice Age, and Current Warm Period reconstructed using coral records from the northern South China Sea
Authors: Deng Wenfeng , Liu Xi , Chen Xuefei , Wei Gangjian , Zeng Ti , Xie Luhua , Zhao Jian‐xin 
Published: December 2016

AbstractFor the global oceans, the characteristics of high‐resolution climate changes during the last millennium remain uncertain because of the limited availability of proxy data. This study reconstructs climate conditions using annually resolved coral records from the South China Sea (SCS) to provide new insights into climate change over the last millennium. The results indicate that the climate of the Medieval Climate Anomaly (MCA, AD 900–1300) was similar to that of the Current Warm Period (CWP, AD 1850‐present), which contradicts previous studies. The similar warmth levels for the MCA and CWP have also been recorded in the Makassar Strait of Indonesia, which suggests that the MCA was not warmer than the CWP in the western Pacific and that this may not have been a globally uniform change. Hydrological conditions were drier/saltier during the MCA and similar to those of the CWP. The drier/saltier MCA and CWP in the western Pacific may be associated with the reduced precipitation caused by variations in the Pacific Walker Circulation. As for the Little Ice Age (LIA, AD 1550–1850), the results from this study, together with previous data from the Makassar Strait, indicate a cold and wet period compared with the CWP and the MCA in the western Pacific. The cold LIA period agrees with the timing of the Maunder sunspot minimum and is therefore associated with low solar activity. The fresher/wetter LIA in the western Pacific may have been caused by the synchronized retreat of both the East Asian Summer Monsoon and the Australian Monsoon.
Synoptic analysis and urban signatures of a heavy rainfall on 7 August 2015 in Beijing
Authors: Yu Miao , Miao Shiguang , Li Qingchun 
Published: December 2016

AbstractA heavy rainfall event that occurred in Beijing on 7 August 2015 was investigated by means of several nonconventional observational data and the Beijing Rapid Update Cycle Model (v3.0). A cold front guided by an upper trough and the wind shear line are main factors influencing this rainfall event. The two factors combined were enhanced after passing the Beijing downtown area. A Nourban land use scenario was employed to analyze the impact of urbanization on this rainfall event. The results show that the urban land use type, which induces the wind shear line, is indispensable in forecasting the rainstorm. The urban land use type leads to gradients of the sensible heat flux, temperature, and wind increasing in the suburban area, which may allow the synoptic systems to merge and enhance. Urbanization caused the precipitation to increase in the downstream suburban area and the spatial distribution of precipitation to become more concentrated. Ensemble tests of different parameterization schemes confirm that the results are reliable.
Assessing crop yield simulations driven by the NARCCAP regional climate models in the southeast United States
Authors: Shin D. W. , Baigorria Guillermo A. , Romero Consuelo C. , Cocke Steve , Oh Ji‐Hyun , Kim Baek‐Min 
Published: December 2016

AbstractA set of the North American Regional Climate Change Assessment Program (NARCCAP) regional climate models is used in crop modeling systems to assess economically valuable agricultural production in the southeast United States, where weather/climate exerts strong impact on agriculture. The maize/peanut/cotton yield amounts for the period of 1981–2003 are obtained in a regularly gridded (~20 km) southeast U.S. using (a) observed, (b) a reanalysis, and (c) the NARCCAP Phase I multimodel data set. It is shown that the regional‐climate model‐driven crop yield amounts are better simulated than the reanalysis‐driven ones. Multimodel ensemble methods are then adopted to examine their usefulness in improving the simulation of regional crop yield amounts and are compared to each other. The bias‐corrected or weighted composite methods combine the crop yield ensemble members better than the simple composite method. In general, the weighted ensemble crop yield simulations match marginally better with the observed‐weather‐driven yields compared to those of the other ensemble methods.
Mass Spectrometry of Biological Molecules
Authors: Fuchs Beate , Schiller Jürgen 
Published: December 2016

AbstractMass spectrometric methods may serve as powerful analytical methods in life sciences and medicine. Mass spectrometry (MS) is comparable in sensitivity to techniques based on chromatography or electrophoresis but has superior resolution. Although there are a number of suitable ionization methods, allowing the analysis of biological molecules that are of high molecular weight and low volatility, there are mainly two ‘soft‐ionization’ techniques that confer only a minimum of degradation of the analyte: MALDI (matrix‐assisted laser desorption/ionization) and ESI (electrospray ionization). The following article provides a short overview on the advantages and drawbacks of MALDI analysis of biological samples. While most applications of MALDI are in the field of protein analysis, the analyses of carbohydrates and lipids are also comprehensively discussed. It is shown that MALDI is a useful tool especially in the field of lipid analysis, whereas with carbohydrate analysis, still a number of problems have to be solved. MALDI is a rapid and very sensitive (from the low picomolar to the attomolar range) tool that tolerates high amounts of impurities (in contrast to ESI), which are typically present in biological samples. A further advantage is that mainly singly charged ions are formed; this enables MALDI to be applied even to the analysis of crude mixtures although ion yields may differ significantly in dependence on the molecules of interest. In comparison with ESI, MALDI detects compounds of higher molecular weights more sensitively, whereas ESI is more suitable for labile compounds. Therefore, the combination of both methods is, in many cases, the ideal solution for a number of analytical problems.
Multidimensional Nuclear Magnetic Resonance of Biomolecules
Authors: Craik David J. , Horne James , Scanlon Martin J. , Nichols Scott R. , Frueh Dominique P. 
Published: December 2016

AbstractNuclear magnetic resonance (NMR) is associated with transitions, induced by radiofrequency (RF) irradiation, between energy levels of nuclei with nonzero spin quantum numbers in a magnetic field. Traditional ‘one‐dimensional’ (1D) NMR spectra are presented as a plot of signal intensity versus applied frequency and provide information about the chemical environment of magnetically active nuclei. This is used to deduce information about the chemical structure and dynamics of molecules containing the magnetically active nuclei (most often protons). The frequencies of individual nuclei are referred to as their chemical shifts. Multidimensional NMR encompasses a range of related techniques, based on the application of a variety of precisely timed RF pulses to the sample, which extends traditional 1D NMR into two‐, three‐, or four‐frequency dimensions. In multidimensional NMR of biomolecules, the most common frequencies correspond to1H in the directly detected dimension and one or more of1H,13C, or15N in the additional dimensions. Peaks in such spectra are defined by their intensity and frequency coordinates in two, three, or four dimensions obtained by extrapolation back to the respective frequency axes, which are in turn determined by the nature of the applied RF pulse sequences. The intensity and chemical shifts of such peaks provide information about the chemical environment, molecular connectivity, or spatial proximity of the participating nuclei. Multidimensional NMR has major advantages over 1D NMR: reduction of peak overlap and provision of information on connectivity (either through bonds or through space). Multidimensional NMR spectroscopy of biomolecules is usually done for samples in solution at millimolar concentration. Where experiments require the use of13C or15N frequencies, it is usually necessary to isotopically enrich the macromolecule with these nuclei to >90%. This is readily achieved with modern molecular biology techniques and does not present a major limitation. As molecular weight increases, spectra exhibit severe overlap and suffer from sensitivity losses. Despite this limitation, it is becoming commonplace to study biological macromolecules up to 50 kDa and molecular assemblies reaching megadaltons.
Understanding the enhanced ductility of TiAl alloys using a hybrid study of in‐situ TEM experiment and molecular dynamics
Authors: Kim Seong‐Woong , Ryu Seung‐Hwa , Na Young‐sang , Kim Seung‐Eon 
Published: December 2016

An in‐situ transmission electron microscopy study was conducted at room temperature in order to understand an underlying mechanism on room temperature ductility of TiAl alloys. Also, melecular dynamics simulation was conducted to calculate the stacking fault energy of TiAl alloys and to show which deformation mode is dominant. From in‐situ straining transmission electron microscopy experiments, it was revealed that the crack path and deformation mode is different between the TiAl alloys with/without room temperature ductility. The crack in TiAl alloys having room temperature ductility interacted with lamellae by forming bridging ligaments between the two α2 lamellae and the γ lamellae. In contrast, the cracks in TiAl alloys without room temperature ductility propagated along grain (colony) boundaries showing brittle intergranular fracture. From the quantitative in‐situ TEM experiements, it was found that the γ lamellar of TiAl alloys having room temperature ductility was deformed by slip (Fig. 1). However, the γ lamellar of TiAl alloys without room temperature ductility was deformed by deformation twin (Fig. 2). The difference in deformation mode was explained by stacking fault energy of the TiAl alloys which was calculated by molecular dynamics. The TiAl alloy with low stacking fault energy was deformed by deformation twin (Fig. 2) whereas the TiAl alloy with high stacking fault energy was deformed by dislocation slip (Fig. 1). Furthermore, the role of lamellar orientation of tensile direction on deformation behavior was examined using Schmid factor of each orientation.
Finally, we proposed the important microstructural factors to have room temperature ductility of TiAl alloys.
The Nanoworkbench: Automated Nanorobotic system inside of Scanning Electron or Focused Ion Beam Microscopes
Authors: Burkart Ivo , Burkart Eva , Klocke Volker , Peters David 
Published: December 2016

The Nanoworkbench is the first system substituting eye‐hand coordination effectively with nano‐precision in a SEM/FIB‐system. It can be imagined how technology could evolve, when tools within a SEM/FIB can be used as easily as tools used under optical microscopes.

Many every day developments would not exist today without preparation, handling and assembly of materials under optical microscopes. There would be no wristwatch, no in vitro fertilization, no mini‐gearbox, just to mention a few. These products depend on using toolsets like tweezers, knives, hooks, probes and several different measurement tools in combination with optical microscopes. But material properties and functionalities also depend on structure dimensions that are smaller than the wavelength of light.
The operators of SEM, FIB or Dual Beam systems generally work without toolsets. One reason for this is the disconnected closed loop operation between human eyes and hands that enable complex operations under optical microscopes without even thinking about it
The two main aspects of the new Nanoworkbech by Klocke Nanotechnik GmbH, the development of its Nanorobotics technology and the applications enabled by it, are described in this paper.

Aspect 1, development of the technology: In general the success of in‐SEM/FIB Nanorobotics depends on the co‐operation of several important modules in one global system. The main developments include:

Nanomanipulators in automation, for movement of end‐effectors and sample handling,

Different end‐effectors for nano‐ probing, cutting, cleaning, force distance or wear measurements, gripping, sorting or material preparation and processing,

Automatic in‐situ tip cleaning process

Automatic 3D position detection of all tools and SEM/FIB

A control of all tool and SEM/FIB sample stage positions in a common global coordinate system,

SEM picture assisted haptic interface by “Live Image Positioning”,

Modular design for fast configuration & teaching of nano‐analytical or nano‐handling processes.

With instantiating these technical demands the Nanoworkbench enables secure and easy usage of toolsets within SEM/FIB systems, for manual operation, for non‐professional users and in high level of automation, e.g. for high throughput industrial processes, even as job‐shop [1].
Aspect 2, development of a series of new applications in one system: Expanding the SEM/FIB to a material processing system and a nano‐analytical workbench opens the door to many applications in all fields of research and development up to industrial production [5]. Several examples of these new interdisciplinary research and development fields will be described during the presentation.
A few examples of Nanoworkbench applications are highlighted in Figure 1. Although these examples may raise the impression of a review about different machines and their usage, this is not the case. Described is the development of the Nanoworkbench.
Electron microscopy characterization of yttrium‐doped barium zirconate electrolytes prepared with Ni additive: Influence of hydrogen treatment
Authors: Haghi‐Ashtiani Paul , Hassine Mohamed BEN , Ciria Desiree , Jimenez‐Melendo Manuel , Aubin Veronique , Dezanneau Guilhem 
Published: December 2016

Proton‐conducting Fuel or Electrolysis Cells (PCFCs) are thought to be a promising alternative to Solid Oxide Fuel/Electrolysis Cells [1‐2]. The most interesting proton conducting materials for electrolytes include doped barium zirconate, doped barium cerate or their solid solution. Recently, an innovative approach was proposed which allowed obtaining dense ceramics with grain size of typically 2‐4 µm. This new process is based on the reactive sintering of all oxide precursors with the use of NiO as sintering aid [2‐4]. Besides being dense, the samples obtained, such as yttrium‐doped barium zirconate (BZY), show a very high proton conduction with little influence of Ni‐species on conduction properties.
We tested the mechanical properties of this BZY material for application as PCFCs electrolyte and we showed that materials made from this process present a fast degradation of mechanical properties when put in hydrogen‐rich conditions.
The objective of the present work was thus to understand the atomic‐scale origin of this fast degradation. For this purpose, different electron microscopy techniques have used such as Scanning Transmission Electron Microscopy (STEM‐HAADF), Energy dispersive spectroscopy (EDS), Electron Energy Loss spectroscopy (EELS). Structural and chemical microscopy analysis show that the sample failure is due to the reduction of NiO nanoparticles at grain boundaries (Figure 1, 2).