bluuebunny/crossref_metadata_2025 huggingface dataset:
A formação do professor de História no Brasil: percurso histórico e periodização
Authors: Nascimento Thiago Rodrigues
Published: July 2016

Nos últimos anos a formação de professores de História tem se tornado objeto de importantes pesquisas realizadas por historiadores e educadores. A vitalidade desse campo de pesquisa pode ser evidenciada no crescente número de trabalhos e artigos expostos e publicados em encontros, como os organizados pela Associação Brasileira de Ensino de História (Abeh), e em periódicos científicos. Entretanto, a maior parte dos estudos se debruça sobre as ‘questões pedagógicas’ e curriculares atuais, concedendo pouca atenção à história dessa formação. O artigo tem como objetivo apresentar e discutir uma periodização possível para análise da história da formação dos professores de História no Brasil. Para tanto, temos como referência teórica autores da história da educação e do ensino de História. Utilizamos, ainda, as diferentes legislações normatizadoras referentes à forma
Professores de história em uma experiência de formação inicial a distância: os significados e os limites da profissionalização
Authors: Ferreira Maria Cláudia
Published: July 2016

O artigo analisa uma experiência de formação a distância (Pró-licenciatura) destinada a professores leigos que atuavam como professores de história no Nordeste brasileiro. Mediante análise de entrevistas, de questionários e das interações no fórum de debates onlinedo curso objetivou-se compreender, da perspectiva dos saberesdocentes, o processo de fazer-seprofessor de história. Com isso foi possível elucidar aspectos das políticas de qualificação profissional dos professores da educação básica em geral, e de história, em particular, bem como constatar que a educação a distância pode significar uma possibilidade real de formação superior, oportunizando mobilidade social e inclusão digital e rompendo barreiras de acesso às Tecnologias Digitais de Informação e Comunicação (TDICs), especialmente para professoras com exaustiva jornada de trabalho e muitos anos de profissão.
Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics
Authors: González-Ibarra A.A. , Nava-Alonso F. , Fuentes-Aceituno J.C. , Uribe-Salas A.
Published: July 2016

This work examines the role of NaOH and Ca(OH)2 on the hydrothermal
decomposition of industrial jarosite deposited by a Mexican company in a
tailings dam. The industrial jarosite is mainly composed by natrojarosite and
contains 150 g Ag/t, showing a narrow particle size distribution, as revealed
by XRD, fire assay, SEM-EDS and laser-diffraction analysis. The effect of the
pH, when using NaOH or Ca(OH)2 as alkalinizing agent was studied by carrying
out decomposition experiments at different pH values and 60?C in a
homogeneous size particle system (pH = 8, 9, 10 and 11) and in a
heterogeneous size particle system (pH = 11). Also, the kinetic study of the
process and the controlling step of the decomposition reaction when NaOH and
Ca(OH)2 are used was determined by fitting the data obtained to the shrinking
core model for spherical particles of constant size. These results, supported
by chemical (EDS), morphological (SEM) and mapping of elements (EDS) analysis
of a partially reacted jarosite particle allowed to conclude that when NaOH
is used, the process kinetics is controlled by the chemical reaction and when
Ca(OH)2 is used, the rate determining step is changed to a diffusion control
through a layer of solid products.
Boost Pressure Control Strategy to Account for Transient Behavior and Pumping Losses in a Two-Stage Turbocharged Air Path Concept
Authors: Albin Thivaharan , Ritter Dennis , Liberda Norman , Abel Dirk
Published: July 2016

Increasingly complex air path concepts are investigated to achieve a substantial reduction in fuel consumption while improving the vehicle dynamics. One promising technology is the two-stage turbocharging for gasoline engines, where a high pressure and a low pressure turbocharger are placed in series. For exploiting the high potential, a control concept has to be developed that allows for coordinated management of the two turbocharger stages. In this paper, the control strategy is investigated. Therefore, the effect of the actuated values on transient response and pumping losses is analyzed. Based on these findings, an optimization-based control algorithm is developed that allows taking both requirements into account. The developed new controller allows achieving a fast transient response, while at the same time reducing pumping losses in stationary operation.
Power Control Strategies of On-Road Charging for Electric Vehicles
Authors: Tan Linlin , Guo Jinpeng , Huang Xueliang , Liu Han , Yan Changxin , Wang Wei
Published: July 2016

On-road charging systems for electric vehicles (EVs) have shown revolutionary potential in extending driving range and reducing battery capacities. The optimal equivalent load resistances to maximize receiving power of each EV according to different EV amounts are investigated. This paper introduces a typical on-road charging system with a single transmitting coil and multiple receiving coils. The equivalent circuit models according to different numbers of EVs are built. Power control strategies with regard to a varying number of EVs are then presented. Specifically, self-adaptive source voltage based on primary current detection is utilized to charge EVs, while the source can support enough EVs by providing the rated power. Otherwise, the source voltage is regulated to its maximum value and the charging energy of each EV is suggested to be controlled by adjusting the individual driving speed. A remarkable feature of the power control strategies is that the charging power for each EV is stable and can compensate for energy losses efficiently. As for urgent power demand from a particular EV with a low battery capacity, the adjustment of the corresponding load resistance is applied to alter the power distribution. The proposed technique has been verified in an experimental prototype.
Review of Special Issues in the First Half of 2016
Authors: Lin Yu-Pin
Published: July 2016

Environments was launched two years ago, in March 2014.[...]
Long Noncoding RNA and mRNA Expression Profiles in the Thyroid Gland of Two Phenotypically Extreme Pig Breeds Using Ribo-Zero RNA Sequencing
Authors: Shen Yifei , Mao Haiguang , Huang Minjie , Chen Lixing , Chen Jiucheng , Cai Zhaowei , Wang Ying , Xu Ningying
Published: July 2016

The thyroid gland is an important endocrine organ modulating development, growth, and metabolism, mainly by controlling the synthesis and secretion of thyroid hormones (THs). However, little is known about the pig thyroid transcriptome. Long non-coding RNAs (lncRNAs) regulate gene expression and play critical roles in many cellular processes. Yorkshire pigs have a higher growth rate but lower fat deposition than that of Jinhua pigs, and thus, these species are ideal models for studying growth and lipid metabolism. This study revealed higher levels of THs in the serum of Yorkshire pigs than in the serum of Jinhua pigs. By using Ribo-zero RNA sequencing—which can capture both polyA and non-polyA transcripts—the thyroid transcriptome of both breeds were analyzed and 22,435 known mRNAs were found to be expressed in the pig thyroid. In addition, 1189 novel mRNAs and 1018 candidate lncRNA transcripts were detected. Multiple TH-synthesis-related genes were identified among the 455 differentially-expressed known mRNAs, 37 novel mRNAs, and 52 lncRNA transcripts. Bioinformatics analysis revealed that differentially-expressed genes were enriched in the microtubule-based process, which contributes to THs secretion. Moreover, integrating analysis predicted 13 potential lncRNA-mRNA gene pairs. These data expanded the repertoire of porcine lncRNAs and mRNAs and contribute to understanding the possible molecular mechanisms involved in animal growth and lipid metabolism.
Assessing a New Method for Measuring Fetal Exposure to Mercury: Newborn Bloodspots
Authors: Nelson Jessica , Edhlund Betsy , Johnson Jean , Rosebush Christina , Holmquist Zachary , Swan Shanna , Nguyen Ruby
Published: July 2016

Background: Measuring mercury in newborn bloodspots to determine fetal exposures is a novel methodology with many advantages. Questions remain, however, about its reliability as an estimate of newborn exposure to mercury. Methods: We studied mercury concentrations in paired bloodspots and cord blood from a convenience sample of 48 Minnesota women and infants. Results: The limit of detection for bloodspots was higher than for cord blood (0.7 and 0.3 μg/L in bloodspots and cord blood, respectively) with the result that mercury was detected in only 38% of newborn bloodspots compared to 62% of cord blood samples. The geometric mean mercury concentration in cord blood was 0.6 μg/L. Mercury concentrations were almost uniformly lower in bloodspots than in cord blood (mean ratio (±SD) = 0.85 ± 0.4), their mean value was significantly less than that for the cord blood (p = 0.02), and the two methods were highly correlated (r = 0.82). Conclusion: These preliminary findings indicate that newborn bloodspot mercury measurements have utility; however, until bloodspot analyses are more sensitive, they are likely to underestimate in utero exposure.
Identification of Pathways in Liver Repair Potentially Targeted by Secretory Proteins from Human Mesenchymal Stem Cells
Authors: Winkler Sandra , Hempel Madlen , Brückner Sandra , Tautenhahn Hans-Michael , Kaufmann Roland , Christ Bruno
Published: July 2016

Background: The beneficial impact of mesenchymal stem cells (MSC) on both acute and chronic liver diseases has been confirmed, although the molecular mechanisms behind it remain elusive. We aim to identify factors secreted by undifferentiated and hepatocytic differentiated MSC in vitro in order to delineate liver repair pathways potentially targeted by MSC. Methods: Secreted factors were determined by protein arrays and related pathways identified by biomathematical analyses. Results: MSC from adipose tissue and bone marrow expressed a similar pattern of surface markers. After hepatocytic differentiation, CD54 (intercellular adhesion molecule 1, ICAM-1) increased and CD166 (activated leukocyte cell adhesion molecule, ALCAM) decreased. MSC secreted different factors before and after differentiation. These comprised cytokines involved in innate immunity and growth factors regulating liver regeneration. Pathway analysis revealed cytokine-cytokine receptor interactions, chemokine signalling pathways, the complement and coagulation cascades as well as the Januskinase-signal transducers and activators of transcription (JAK-STAT) and nucleotide-binding oligomerization domain-like receptor (NOD-like receptor) signalling pathways as relevant networks. Relationships to transforming growth factor β (TGF-β) and hypoxia-inducible factor 1-α (HIF1-α) signalling seemed also relevant. Conclusion: MSC secreted proteins, which differed depending on cell source and degree of differentiation. The factors might address inflammatory and growth factor pathways as well as chemo-attraction and innate immunity. Since these are prone to dysregulation in most liver diseases, MSC release hepatotropic factors, potentially supporting liver regeneration.
Crack Healing Performance of PVA-Coated Granules Made of Cement, CSA, and Na2CO3 in the Cement Matrix
Authors: Lee Yong-Soo , Ryou Jae-Suk
Published: July 2016

Various self-healing methods for concrete, such as the use of supplementary cementitious materials, adhesive agents, mineral admixtures, and bacteria, have been suggested to date, and each of these has merits and demerits. Among these, however, the use of cementitious materials may be appropriate due to their good healing efficiency, low cost, and compatibility with the cement matrix. In this study, granulation and coating methods were applied to a new cementitious composite material. The self-healing property of these materials was controlled by the polyvinyl alcohol (PVA) coating until cracks were created. Water dissolved the PVA coating after entering through the cracks, and reacted with the healing materials to generate healing products. The self-healing performance was evaluated at various elapsed times through the measurement of the crack widths, visual observation, and examination of the microscopic images. Simultaneously, a water permeability test was performed and the dynamic modulus of elasticity was measured to verify the recovery of the cracks. In addition, the healing products that had been formed in the cracks were analyzed via X-ray diffraction (XRD) and scanning electron microscopy (SEM).
The Effect of Chromium on the Roasting Process of Vanadium Extraction
Authors: Liu Dong , Xue Xiangxin , Yang He
Published: July 2016

We simulated the roasting process of chromium by mixing Cr2O3 and Na2CO3 to analyze the influence of chromium on roasting vanadium slag. Samples were characterized by XRD, thermal analysis and SEM at different temperatures: Cr2O3 and Na2CO3 began to react at 500 °C. When the chromium oxide content was about 3.2%, the conversion rate of V reached the maximum value of 95%.
A Label-Free Microelectrode Array Based on One-Step Synthesis of Chitosan–Multi-Walled Carbon Nanotube–Thionine for Ultrasensitive Detection of Carcinoembryonic Antigen
Authors: Xu Huiren , Wang Yang , Wang Li , Song Yilin , Luo Jinping , Cai Xinxia
Published: July 2016

Carcinoembryonic antigen (CEA) has been an extensively used tumor marker responsible for clinical early diagnosis of cervical carcinomas, and pancreatic, colorectal, gastric and lung cancer. Combined with micro-electro mechanical system (MEMS) technology, it is important to develop a novel immune microelectrode array (MEA) not only for rapid analysis of serum samples, but also for cell detection in vitro and in vivo. In this work, we depict a simple approach to modify chitosan–multi-walled carbon nanotubes–thionine (CS–MWCNTs–THI) hybrid film through one-step electrochemical deposition and the CS-MWCNTs-THI hybrid films are successfully employed to immobilize anti-CEA for fabricating simple, label-free, and highly sensitive electro-chemical immune MEAs. The detection principle of immune MEA was based on the fact that the increasing formation of the antigen-antibody immunocomplex resulted in the decreased response currents and the relationship between the current reductions with the corresponding CEA concentrations was directly proportional. Experimental results indicated that the label-free MEA had good selectivity and the limit of detection for CEA is 0.5 pg/mL signal to noise ratio (SNR) = 3. A linear calibration plot for the detection of CEA was obtained in a wide concentration range from 1 pg/mL to 100 ng/mL (r = 0.996). This novel MEA has potential applications for detecting CEA for the research on cancer cells and cancer tissue slices as well as for effective early diagnosis.
Evaluating Biosphere Model Estimates of the Start of the Vegetation Active Season in Boreal Forests by Satellite Observations
Authors: Böttcher Kristin , Markkanen Tiina , Thum Tea , Aalto Tuula , Aurela Mika , Reick Christian , Kolari Pasi , Arslan Ali , Pulliainen Jouni
Published: July 2016

The objective of this study was to assess the performance of the simulated start of the photosynthetically active season by a large-scale biosphere model in boreal forests in Finland with remote sensing observations. The start of season for two forest types, evergreen needle- and deciduous broad-leaf, was obtained for the period 2003–2011 from regional JSBACH (Jena Scheme for Biosphere–Atmosphere Hamburg) runs, driven with climate variables from a regional climate model. The satellite-derived start of season was determined from daily Moderate Resolution Imaging Spectrometer (MODIS) time series of Fractional Snow Cover and the Normalized Difference Water Index by applying methods that were targeted to the two forest types. The accuracy of the satellite-derived start of season in deciduous forest was assessed with bud break observations of birch and a root mean square error of seven days was obtained. The evaluation of JSBACH modelled start of season dates with satellite observations revealed high spatial correspondence. The bias was less than five days for both forest types but showed regional differences that need further consideration. The agreement with satellite observations was slightly better for the evergreen than for the deciduous forest. Nonetheless, comparison with gross primary production (GPP) determined from CO2 flux measurements at two eddy covariance sites in evergreen forest revealed that the JSBACH-simulated GPP was higher in early spring and led to too-early simulated start of season dates. Photosynthetic activity recovers differently in evergreen and deciduous forests. While for the deciduous forest calibration of phenology alone could improve the performance of JSBACH, for the evergreen forest, changes such as seasonality of temperature response, would need to be introduced to the photosynthetic capacity to improve the temporal development of gross primary production.
Extracting Canopy Surface Texture from Airborne Laser Scanning Data for the Supervised and Unsupervised Prediction of Area-Based Forest Characteristics
Authors: Niemi Mikko , Vauhkonen Jari
Published: July 2016

Area-based analyses of airborne laser scanning (ALS) data are an established approach to obtain wall-to-wall predictions of forest characteristics for vast areas. The analyses of sparse data in particular are based on the height value distributions, which do not produce optimal information on the horizontal forest structure. We evaluated the complementary potential of features quantifying the textural variation of ALS-based canopy height models (CHMs) for both supervised (linear regression) and unsupervised (k-Means clustering) analyses. Based on a comprehensive literature review, we identified a total of four texture analysis methods that produced rotation-invariant features of different order and scale. The CHMs and the textural features were derived from practical sparse-density, leaf-off ALS data originally acquired for ground elevation modeling. The features were extracted from a circular window of 254 m2 and related with boreal forest characteristics observed from altogether 155 field sample plots. Features based on gray-level histograms, distribution of forest patches, and gray-level co-occurrence matrices were related with plot volume, basal area, and mean diameter with coefficients of determination (R2) of up to 0.63–0.70, whereas features that measured the uniformity of local binary patterns of the CHMs performed poorer. Overall, the textural features compared favorably with benchmark features based on the point data, indicating that the textural features contain additional information useful for the prediction of forest characteristics. Due to the developed processing routines for raster data, the CHM features may potentially be extracted with a lower computational burden, which promotes their use for applications such as pre-stratification or guiding the field plot sampling based solely on ALS data.
Multi-Temporal Evaluation of Soil Moisture and Land Surface Temperature Dynamics Using in Situ and Satellite Observations
Authors: Pablos Miriam , Martínez-Fernández José , Piles María , Sánchez Nilda , Vall-llossera Mercè , Camps Adriano
Published: July 2016

Soil moisture (SM) is an important component of the Earth’s surface water balance and by extension the energy balance, regulating the land surface temperature (LST) and evapotranspiration (ET). Nowadays, there are two missions dedicated to monitoring the Earth’s surface SM using L-band radiometers: ESA’s Soil Moisture and Ocean Salinity (SMOS) and NASA’s Soil Moisture Active Passive (SMAP). LST is remotely sensed using thermal infrared (TIR) sensors on-board satellites, such as NASA’s Terra/Aqua MODIS or ESA & EUMETSAT’s MSG SEVIRI. This study provides an assessment of SM and LST dynamics at daily and seasonal scales, using 4 years (2011–2014) of in situ and satellite observations over the central part of the river Duero basin in Spain. Specifically, the agreement of instantaneous SM with a variety of LST-derived parameters is analyzed to better understand the fundamental link of the SM–LST relationship through ET and thermal inertia. Ground-based SM and LST measurements from the REMEDHUS network are compared to SMOS SM and MODIS LST spaceborne observations. ET is obtained from the HidroMORE regional hydrological model. At the daily scale, a strong anticorrelation is observed between in situ SM and maximum LST (R ≈ − 0.6 to −0.8), and between SMOS SM and MODIS LST Terra/Aqua day (R ≈ − 0.7). At the seasonal scale, results show a stronger anticorrelation in autumn, spring and summer (in situ R ≈ − 0.5 to −0.7; satellite R ≈ − 0.4 to −0.7) indicating SM–LST coupling, than in winter (in situ R ≈ +0.3; satellite R ≈ − 0.3) indicating SM–LST decoupling. These different behaviors evidence changes from water-limited to energy-limited moisture flux across seasons, which are confirmed by the observed ET evolution. In water-limited periods, SM is extracted from the soil through ET until critical SM is reached. A method to estimate the soil critical SM is proposed. For REMEDHUS, the critical SM is estimated to be ∼0.12 m 3 /m 3 , stable over the study period and consistent between in situ and satellite observations. A better understanding of the SM–LST link could not only help improving the representation of LST in current hydrological and climate prediction models, but also refining SM retrieval or microwave-optical disaggregation algorithms, related to ET and vegetation status.
Integrated Multi-Trophic Recirculating Aquaculture System for Nile Tilapia (Oreochlomis niloticus)
Authors: Sri-uam Puchong , Donnuea Seri , Powtongsook Sorawit , Pavasant Prasert
Published: July 2016

Three densities of the sex-reversed male Nile tilapia, Oreochromis niloticus (20, 25, 50 fish/m3) were cultivated in an integrated multi-trophic recirculating aquaculture system (IMRAS) that involves the ecological relationship between several living organisms, i.e., phytoplankton, zooplankton, and aquatic plants. The results indicated that, by providing proper interdependency between various species of living organisms, the concentrations of ammonia, nitrite, nitrate, and phosphate in the system were maintained below dangerous levels for Nile tilapia throughout the cultivation period. The highest wet weight productivity of Nile tilapia of 11 ± 1 kg was achieved at a fish density of 50 fish/m3. The aquatic plants in the treatment tank could effectively uptake the unwanted nitrogen (N) and phosphorus (P) compounds with the highest removal efficiencies of 9.52% and 11.4%, respectively. The uptake rates of nitrogen and phosphorus by aquatic plants could be ranked from high to low as: Egeria densa > Ceratophyllum demersum > Vallisneria spiralis and Vallisneria americana > Hygrophila difformis. The remaining N was further degraded through nitrification process, whereas the remaining P could well precipitate in the soil sediment in the treatment tank.
Forecasting the Allocation Ratio of Carbon Emission Allowance Currency for 2020 and 2030 in China
Authors: Zeng Shihong , Chen Jiuying
Published: July 2016

Many countries and scholars have used various strategies to improve and optimize the allocation ratios for carbon emission allowances. This issue is more urgent for China due to the uneven development across the country. This paper proposes a new method that divides low-carbon economy development processes into two separate periods: from 2020 to 2029 and from 2030 to 2050. These two periods have unique requirements and emissions reduction potential; therefore, they must involve different allocation methods, so that reduction behaviors do not stall the development of regional low-carbon economies. During the first period, a more deterministic economic development approach for the carbon emission allowance allocation ratio should be used. During the second period, more adaptive and optimized policy guidance should be employed. We developed a low-carbon economy index evaluation system using the entropy weight method to measure information filtering levels. We conducted vector autoregressive correlation tests, consulted 60 experts for the fuzzy analytic hierarchy process, and we conducted max-min standardized data processing tests. This article presents first- and second-period carbon emission allowance models in combination with a low-carbon economy index evaluation system. Finally, we forecast reasonable carbon emission allowance allocation ratios for China for the periods starting in 2020 and 2030. A good allocation ratio for the carbon emission allowance can help boost China’s economic development and help the country reach its energy conservation and emissions reduction goals.
Large-Scale Agricultural Management and Soil Meso- and Macrofauna Conservation in the Argentine Pampas
Authors: Bedano José , Domínguez Anahí
Published: July 2016

Soil is the most basic resource for sustainable agricultural production; it promotes water quality, is a key component of the biogeochemical cycles and hosts a huge diversity of organisms. However, we are not paying enough attention to soil degradation produced by land use. Modern agriculture has been successful in increasing yields but has also caused extensive environmental damage, particularly soil degradation. In the Argentine Pampas, agriculturization reached a peak with the generalized use of the no-till technological package: genetically modified soybeans tolerant to glyphosate, no-till, glyphosate, and inorganic fertilizers. This phenomenon has been widely spread in the country; the no-till package has been applied in large areas and has been used by tenants in a 60%–70% of cultivated lands. Thus, those who were involved in developing management practices may not be the same as those who will face degradation issues related to those practices. Indeed, most evidence reviewed in this paper suggests that the most widely distributed practices in the Pampas region are actually producing severe soil degradation. Biological degradation is particularly important because soil biota is involved in numerous soil processes on which soil functioning relies, affecting soil fertility and productivity. For example, soil meso- and macrofauna are especially important in nutrient cycling and in soil structure formation and maintenance, and they are key components of the network that links microbial process to the scale of fields and landscapes where ecosystem services are produced. However, the knowledge of the impact of different agricultural managements on soil meso- and macrofauna in Pampas agroecosystems is far from conclusive at this stage. The reason for this lack of definite conclusions is that this area has been given less attention than in other parts of the world; the response of soil fauna to agricultural practices is complex and taxa-dependent; and there is a wide variety of practices in the main types of agricultural systems, making generalizations difficult. A review of the existing studies on soil meso- and macrofauna in agroecosystems, revealed that (a) agricultural soils, regardless of farming system, are strongly modified in biological aspects compared to the same soils without human interventions; (b) there are no conclusive results about no-till benefits compared to reduced tillage or conventional tillage; (c) agricultural managements that are alternative to the traditional conventional systems are very poorly represented in research.
Building Sustainable Smallholder Cooperatives in Emerging Market Economies: Findings from a Five-Year Project in Kenya
Authors: Meador John , O’Brien David , Cook Michael , Grothe Greg , Werner LuAnn , Diang’a Daniel , Savoie Rebecca
Published: July 2016

A comparative study of two smallholder dairy cooperatives in Kenya examines the question: what factors are conducive to producing sustainable smallholder cooperatives that can gain entry into the vertical value chain in liberalized post-colonial economies? The relative weight of income advantage; selective individual incentives and, social capital on maintaining member patronage are assessed within variable environmental constraints and opportunities facing different cooperatives. The methodology includes case study observation of the cooperatives during a five-year period, as well as sample surveys of members and non-members that include indicators of dairy income; reasons why farmers elect to join or not join the cooperative; and assessments of the importance of different services provided by the cooperative. The findings show how the relative weight of specific incentives for cooperative membership can vary from one environment to another within the same nation. The most important finding is that maintaining sustainable smallholder cooperatives within an increasingly competitive environment depends on the ability of managers to create business strategies that are compatible with the cooperative’s environmental constraints but, at the same time, incentivize members’ patronage.
Development of highly faceted reduced graphene oxide-coated copper oxide and copper nanoparticles on a copper foil surface
Authors: Ortega-Amaya Rebeca , Matsumoto Yasuhiro , Espinoza-Rivas Andrés M , Pérez-Guzmán Manuel A , Ortega-López Mauricio
Published: July 2016

This work describes the formation of reduced graphene oxide-coated copper oxide and copper nanoparticles (rGO-Cu2ONPs, rGO-CuNPs) on the surface of a copper foil supporting graphene oxide (GO) at annealing temperatures of 200–1000 °C, under an Ar atmosphere. These hybrid nanostructures were developed from bare copper oxide nanoparticles which grew at an annealing temperature of 80 °C under nitrogen flux. The predominant phase as well as the particle size and shape strongly depend on the process temperature. Characterization with transmission electron microscopy and scanning electron microscopy indicates that Cu or Cu2O nanoparticles take rGO sheets from the rGO network to form core–shell Cu–rGO or Cu2O–rGO nanostructures. It is noted that such ones increase in size from 5 to 800 nm as the annealing temperature increases in the 200–1000 °C range. At 1000 °C, Cu nanoparticles develop a highly faceted morphology, displaying arm-like carbon nanorods that originate from different facets of the copper crystal structure.
ON THE MAGNETISM AND DYNAMICS OF PROMINENCE LEGS HOSTING TORNADOES
Authors: Martínez González M. J. , Ramos A. Asensio , Arregui I. , Collados M. , Beck C. , Rodríguez J. de la Cruz
Published: July 2016

Solar tornadoes are dark vertical filamentary structures observed in the extreme ultraviolet associated with prominence legs and filament barbs. Their true nature and relationship to prominences requires an understanding of their magnetic structure and dynamic properties. Recently, a controversy has arisen: is the magnetic field organized forming vertical, helical structures or is it dominantly horizontal? And concerning their dynamics, are tornadoes really rotating or is it just a visual illusion? Here we analyze four consecutive spectro-polarimetric scans of a prominence hosting tornadoes on its legs, which helps us shed some light on their magnetic and dynamical properties. We show that the magnetic field is very smooth in all the prominence, which is probably an intrinsic property of the coronal field. The prominence legs have vertical helical fields that show slow temporal variation that is probably related to the motion of the fibrils. Concerning the dynamics, we argue that (1) if rotation exists, it is intermittent, lasting no more than one hour, and (2) the observed velocity pattern is also consistent with an oscillatory velocity pattern (waves).
Risk Factors of End Stage Renal Disease in Peshawar, Pakistan: Odds Ratio Analysis
Authors: Khan Salahuddin , Hussain Tariq , Salahuddin Najma , Mehreen Salahuddin
Published: July 2016

AIM: The basic aim of this study was to discover the association of End Stage Renal Disease (ESRD) with various risk factors. End Stage Renal Failure is the last stage of the chronic renal failure in which kidneys become completely fail to function.MATERIALS AND METHODS: The data were collected from the patients of renal diseases from three major hospitals in Peshawar, Pakistan. Odds ratio analysis was performed to examine the relationship of ESRD (a binary response variable) with various risk factors: Gender, Diabetic, Hypertension, Glomerulonephritis, Obstructive Nephropathy, Polycystic kidney disease, Myeloma, SLE Nephritis, Heredity, Hepatitis, Excess use of Drugs, heart problem and Anemia.RESULTS: Using odds ratio analysis, the authors found that the ESRD in diabetic patients was 11.04 times more than non-diabetic patients and the ESRD were 7.29 times less in non-hypertensive patients as compared to hypertensive patients. Similarly, glomerulonephritis patients had 3.115 times more risk of having ESRD than non-glomerulonephritis. Other risk factors may also, to some extent, were causes of ESRD but turned out insignificant due to stochastic sample.CONCLUSION: The authors concluded that there is a strong association between ESRD and three risk factors, namely diabetes, hypertension and glomerulonephritis.
Qui donne son corps à la science ?
Authors: Naïditch Nicolas
Published: July 2016

Cet article est dédié à l’analyse de la base de données de l’Association des Dons du Corps de Tours. Celle-ci permet d’appréhender quantitativement certaines caractéristiques à l’échelle de l’institution et des donateurs. À Tours, le don du corps est payant. De facto , ce sont les donateurs seuls qui en assument le prix. Dès lors, il semble pertinent d’en interroger les conséquences sur le laboratoire d’anatomie et sur le profil des personnes qui donnent leur corps ou qui, le cas échéant, annulent leur don.
Anconeus Epitrochlearis Muscle Causing Ulnar Neuropathy at the Elbow: Clinical and Neurophysiological Differential Diagnosis
Authors: Erdem Bagatur A. , Yalcin Mehmet Burak , Ozer Utku Erdem
Published: July 2016

Ulnar neuropathy at the elbow is the second most frequent entrapment neuropathy and is considered idiopathic in most patients. However, several anatomic variations, including the anconeus epitrochlearis muscle, have been reported to cause ulnar nerve compression. The anconeus epitrochlearis muscle is a common anatomic variation, with a prevalence of up to 34%, but the clinical diagnosis of ulnar neuropathy of the elbow as a result of this variation is rare, with an unknown prevalence. It is a congenital accessory muscle between the medial humeral epicondyle and the olecranon that covers the posterior aspect of the cubital tunnel and is usually an operative finding, not a preoperative diagnosis. Ulnar neuropathy as a result of the anconeus epitrochlearis muscle usually has different characteristics than idiopathic disease, including younger age at onset, more rapid progression with a short duration of symptoms, distinct neurophysiology with velocity drop or conduction block of the ulnar nerve, and edema of the anconeus epitrochlearis muscle on magnetic resonance imaging. Neurophysiologic findings in anconeus epitrochlearis–associated ulnar neuropathy indicate subacute onset of symptoms rather than the chronic demyelinating process that is seen in idiopathic ulnar neuropathy. Medial elbow pain may be more exacerbated in these patients rather than the more common sensorial symptoms. This is probably the result of static compression of the nerve and increased cubital tunnel pressure, even when the elbow is in extension. This article describes a case of ulnar nerve entrapment of the elbow in a 28-year-old woman as a result of compression by the anconeus epitrochlearis muscle and includes magnetic resonance imaging findings, surgical correlations, and clinical and neurophysiologic findings. [
Orthopedics.
2016; 39(5):e988–e991.]
Corneal Collagen Cross-linking in Advanced Keratoconus: A 4-Year Follow-up Study
Authors: Giacomin Natalia T. , Netto Marcelo V. , Torricelli André A. M. , Marino Gustavo K. , Bechara Samir J. , Espíndola Rodrigo F. , Santhiago Marcony R.
Published: July 2016

PURPOSE:

To analyze the safety and efficacy of standard corneal collagen cross-linking (CXL) in advanced cases of progressive keratoconus after 4 years of follow-up.

METHODS:

A retrospective case series of patients with advanced progressive keratoconus (stages 3 and 4 of Amsler-Krumeich classification) underwent standard CXL treatment. The parameters examined were changes in uncorrected visual acuity (UDVA), corrected visual acuity (CDVA), keratometry values (mean, flat, steep, and apical), pachymetry, and endothelial cell count at the baseline and at 12, 24, and 48 months postoperatively.

RESULTS:

Forty eyes of 40 patients were enrolled in the study. The mean patient age was 22.5 years (range: 15 to 37 years). Both mean UDVA and CDVA remained stable during the time points; no statistically significant change was noted. Although a slight reduction was observed in all keratometric readings, a statistically significant reduction was only reached in the apical keratometry (
P
= .037) at 4 years after CXL. A significant reduction in the corneal thickness was also found (ultrasonic: 388 ± 49 to 379 ± 48
μ
m; slit-scanning: 362 ± 48 to 353 ± 51
μ
m); however, this change was likely not clinically meaningful. Endothelial cell count was not significantly different at the end of the study. Treatment failure or progression was noted in two patients (5%) over the follow-up period.

CONCLUSIONS:

Standard CXL treatment was safe and able to stabilize both visual acuity and topographic parameters at 4 years of follow-up in eyes with advanced keratoconus.

[
J Refract Surg.
2016;32(7):459–464.]
Optimized Visual Outcome After Asymmetrical Multifocal IOL Rotation
Authors: Pazo Eric E. , Richoz Olivier , McNeely Richard , Millar Zachary A. , Moore Tara C.B. , Moore Jonathan E.
Published: July 2016

PURPOSE:

To report improved visual outcome after rotation of an asymmetrical multifocal intraocular lens (IOL).

METHODS:

Case report.

RESULTS:

A 58-year-old patient underwent bilateral phacoemulsification with asymmetrical multifocal IOL implantation. Postoperative uncorrected distance visual acuity (UDVA) was 0.0 logMAR (20/20 Snellen) and uncorrected near visual acuity was 0.0 logMAR (20/20 Snellen) in both eyes. Quality of vision questionnaire scores for day and night were 5 and 7, respectively. The center of the multifocal IOL in the dominant eye was initially found to be 0.2 mm superotemporally displaced, increasing the percentage area of ‘near-add’ compared to ‘distance-add’ within the physiological pupil. Rotation of this IOL 120° clockwise greatly improved the IOL centration within the pupil center and resulted in an immediate improvement in UDVA to −0.1 logMAR (20/16 Snellen) and quality of vision questionnaire scores to 8 and 9, respectively.

CONCLUSIONS:

Assessment of the centration of an asymmetrical multifocal IOL is important, particularly if there are dysphotoptic or other visual complaints.

[
J Refract Surg
. 2016;32(7):494–496.]
Evaluation of the Robustness of Current Quantitative Criteria for Keratoconus Progression and Corneal Cross-linking
Authors: Prakash Gaurav , Philip Reena , Srivastava Dhruv , Bacero Ruthchel
Published: July 2016

PURPOSE:

To evaluate the robustness of numerical indications of corneal cross-linking by evaluating the inter-session reliability of recently used parameters of progression in keratoconus.

METHODS:

In this observational study, 100 eyes of 100 patients with keratoconus underwent analysis with the Sirius Scheimpflug Topography System (CSO, Firenze, Italy) by a single user. Two sessions (three scans per session) were performed 2 to 4 weeks apart. Cases having poor quality scans, recent visual deterioration, and ocular surgery were excluded. The corneal variables measured were thinnest point and apex characteristics (pachymetry, polar coordinates), volume, central simulated keratometry (flat, steep, average, astigmatism), central corneal thickness, maximum elevation (anterior, posterior), symmetry indices (front, back), and Baiocchi-Calossi-Versaci index. Intra-session (first session, all three measurements) and inter-session (one measurement from each session, selected randomly) statistics were computed.

RESULTS:

There were no significant differences in the six measurements for all variables (
P
> .05, analysis of variance). The intra-session and inter-session intraclass correlations were high (0.937 to 0.997) and within-subject standard deviations (S
w
) were satisfactory (< 5
µ
m for thickness, < 0.50 diopters [D] for curvature, and < 0.11 mm, < 5° for polar coordinates). Inter-session repeatability (2.77 × S
w
) was found to be satisfactory when compared to previously used central keratometric (> 1.00 D increase) or pachymetric (> 2%/> 5% decrease) guidelines to define progression. Apex power repeatability (1.24 D) was found to be poorer than previously used recommendations (1.00 D change).

CONCLUSIONS:

The criteria used to define keratoconus progression were satisfactory when compared to inter-session reliability of corneal parameters. Because higher variability was noted at apex, its curvature repeatability cut-off may be raised to 1.25 D for identifying progressive keratoconus.

[
J Refract Surg.
2016;32(7):465–472.]
Mujer y poder en el reino nazarí de Granada: la sultana Fāṭima bint al-Aḥmar, la perla central del collar de la dinastía (siglo XIV)
Authors: Boloix Gallardo Bárbara
Published: July 2016

En la historia del reino nazarí de Granada, hubo mujeres que traspasaron el umbral del harén para ejercer importantes papeles en distintos ámbitos de la corte. Tal fue, en concreto, el caso de la sultana Fāṭima bint al-Aḥmar (m. 749/1349), hija del emir Muḥammad II, quien puede ser considerada la primera fémina conocida de esta estirpe en participar en los asuntos políticos del reino. Dada la gran influencia que esta mujer llegó a ejercer en el ámbito político, el presente artículo estará dedicado a la reconstrucción de su vida y de su personalidad, en función de la información suministrada por las fuentes árabes conservadas. Asimismo, se analizará de manera profunda su actividad política durante los complejos reinados de sus dos hermanos, Muḥammad III y Naṣr, de su primogénito Ismā῾īl I, y de sus dos nietos, Muḥammad IV y Yūsuf I, durante los cuales la labor de Fāṭima resultó decisiva en los designios del reino de Granada.
Empleo del bloque de yeso en la determinación de humedad en las postas de cemento. (l)
Authors: Tobío José María
Published: July 2016

Not available
Effect of Mixed Filler on Thermal Properties of Foodstuff Conveyor Belts Compound Using an Industrial Microwave Pre-Heating
Authors: Limhengha Suphatchakorn , Limnararat Sunpasit , Sriseubsai Wipoo
Published: July 2016

This study presented the utilization of microwave power for heating of epoxidized natural rubber-50 compounding (ENR50c) with andwithout mixed filler in which the sulfur contents were 1.0, 1.5 and 2.0 parts per hundred parts of dried rubber by weight basis, respectively. The microwave power used was varied in a range of 340-1,700 W with a constant frequency of 2.45 GHz. The mixed filler significantly affected the relative dielectric constant, relative loss factor and loss tangent coefficient. The microwave power and time strongly influenced the temperature of the specimen. The longer time and higher microwave power resulted in higher temperature of the specimen. On the contrary, the thickness of specimen inversely affected the temperature of the specimen. The lower temperature was obtained from the thicker specimen.
Investigation on the Effect of Crystal Orientation Dependence of Pulse Porous Silicon for White Light Emission
Authors: Abd Wahab Nurul Hanida , Abd Rahim Alhan Farhanah , Mohamad Latar Fatin Izzanis , Mahmood Ainorkhilah
Published: July 2016

Porous silicon (PS) was formed by using an electrochemical pulse etching (PC) and conventional direct current (DC) etching techniques. The study aims to compare the effect of crystal orientations (n-type (100) and n-type (111)) on the formation of the PS under various conditions. For DC etching technique, the silicon wafers were etched in Hydrofluoric (HF) based solution with a current density of J=10 mA/cm2 for 30 minutes. While for the PC process, an electroless chemical etching with a different delay time (Td) of 0 min and 2 min were imposed before PC process starts. After that, the pulse current of J=10 mA/cm2 with the cycle time (T) of 10 ms and pause time (Toff) of 4ms were supplied in 30 min etching time in HF based electrolyte. Three samples from n-type (100) are DC1, PC1 and PC2 while the three samples from n-type (111) are DC2, PC3, and PC4 respectively. Field Emission Scanning Electron Microscopy (FESEM) images showed that the samples from n-type (100) produce more uniform circular structures and dense compared to n-type (111). The introduction of 2 minutes delay during PC process resulted in better structural of PS formation and also the optical properties shown by the Raman and Photoluminescence (PL) spectroscopies. For PL observation, the as grown Si shows no emission at the visible spectrum while all the PS samples (DC and PC techniques) exhibited significant broad spectrum between 500 nm to 900 nm respectively. It can be seen that the uniform circular pore of n-type (100) enhanced the PL emission indicated by the higher PL intensity (PC1 and PC2) compared to PC3 and PC4 from n-type (111). Raman spectroscopy showed that an improvement in the crystalline quality of PS in PC technique compared to DC indicated by the reduction of full width at half maximum (FWHM).
The Effect of Iron Oxide on the Mechanical and Ageing Properties of Y-TZP Ceramic
Authors: Sivanesan Sivakumar , Teow Hsien Loong , Singh Ramesh , Niakan Ali , Mase Nobuyuki
Published: July 2016

A small amount of iron oxide (Fe2O3) was added to the commercially available 3 mol% Y-TZP as a sintering aid over a temperature range of 1250°C to 1500°C. Sintered samples were then evaluated to determine the bulk density, Vickers hardness, and fracture toughness. In addition, hydrothermal ageing experiments to determine the tetragonal phase stability were performed on selected sintered samples in superheated steam at 180°C / 10 bar for up to 24 hours. Based on the work carried out, it was revealed that additions of Fe2O3 particularly 0.3 wt% was indeed beneficial in aiding densification, improving the matrix stiffness and hardness when compared to undoped Y-TZP sintered at temperatures below 1350°C. Addition of Fe2O3 was found to have negligible effects on the fracture toughness of all samples with the exception of the 0.5 and 1 wt% doped Y-YZP sintered above 1400°C. Hydrothermal ageing resistance of Y-TZP was found to be enhanced with the addition of Fe2O3 in the Y-TZP matrix.
Effect of Ethylene Glycol on Polymeric Membrane Fabrication for Membrane Distillation
Authors: Chong Kok Chung , Lim Chu Ern , Lai Soon Onn , Lau Woei Jye
Published: July 2016

Membrane distillation (MD) is a membrane separation process first introduced in 1963 by Bodell whereby the major driving force is by vapor pressure difference between the feed and permeate induced by temperature gradient. The MD applications mainly focus on seawater desalination and other industry application such as extraction of fruit juice. In this study, hydrophobic polyvinylidene fluoride (PVDF) hollow fiber membranes were fabricated by wet/dry phase inversion method with 1-methyl-2-pyrrolidone (NMP) as solvents and ethylene glycol (EG) as non solvent additives. The effect of the additives on the membrane formation was studied based on the results from membrane morphology investigation through scanning electron microscope (SEM) and porosity calculation based on gravitational method. The SEM image indicated the membrane morphology changed from finger like layer extending from inner to outer surface to a finger like layer separated by microvoid attributed addition of ethylene glycol which might lead to permeate flux enhancement. Furthers, results from the gravitational test reveal that the addition of ethylene glycol demonstrated a positive effect on the porosity of the membrane. Later, the membranes were tested by membrane distillation process in sodium chloride removal varying feed inlet temperature to investigate the permeate flux performance of the membrane.