bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling Process of Spark Plasma Sintering of Powder Materials by Finite Element Method
Authors: Yushin Denis Igorevich , Smirnov Andrey Vladimirovich , Solis Pinargote Nestor Washington , Peretyagin Pavel Yurievich , Torrecillas San Millan Ramon
Published: November 2015

This paper investigates and analyses use of numerical modeling by finite element method (FEM) at studying of consolidation processes of materials from powder by spark plasma sintering (SPS). Tasks of SPS process optimization is discussed in detail. Examples of numeric analysis of SPS of current conducting and non-conducting materials are given. Numeric modeling of sample sintering with hybrid method when SPS process is combined with hot pressing (HP) process is studied. Also paper presents development prospects of principles of SPS process numeric modeling.
Determination of True Temperature in Selective Laser Melting of Metal Powder Using Infrared Camera
Authors: Doubenskaia Maria Andreyevna , Zhirnov Ivan Vladimirovich , Teleshevskiy Vladimir Ilyich , Bertrand Philippe , Smurov Igor Yurievich
Published: November 2015

The objective of this study is to restore the true temperature in during the process of Selective Laser Melting (SLM) of metal powder (in the present case INOX 316L), that is the actual problem in laser assisted additive technologies. To meet this objective, at the first stage, the temperature was measured on the surface of metal substrate INOX 304L without a powder layer. Based on the results of studies the method of temperature measurementof the molten pool surface on metallic plates and during melting of metal powder layer, that were exposed to laser radiation, using an infrared camera (IR), in the present case FLIR Phoenix RDAS TM, was proposed. To restore the true temperature based on the brightness temperature values measured by IR camera, the results of temperature measurements were compared with the width of the molten track on the surface of the plate in the absence of powder. In case of SLM, the results of IR camera measurements were compared with the width of a welded track (bead). The true temperature profiles and temperature gradients values were determined along the axis of the laser beam for melting of plates without powder. In the case of powder melting, the developed method allows to determine the influence of several key SLM parameters on the molten pool shape.
The development of an implementation framework for service-learning during the undergraduate nursing programme in the Western Cape Province
Authors: Julie Hester
Published: November 2015

Background: Service-learning (SL) is a contested field of knowledge and issues of sustainability and scholarship have been raised about it. The South African Higher Education Quality Committee (HEQC) has provided policy documents to guide higher education institutions (HEIs) in the facilitation of SL institutionalisation in their academic programmes. An implementation framework was therefore needed to institutionalise the necessary epistemological shifts advocated in the national SL policy guidelines.Objectives: This article is based on the findings of a doctoral thesis that aimed at developing an SL implementation framework for the School of Nursing (SoN) at the University of the Western Cape (UWC).Method: Mixed methods were used during the first four phases of the design and developmenti ntervention research model developed by Rothman and Thomas.Results: The SL implementation framework that was developed during Phase 3 specified the intervention elements to address the gaps that had been identified by the core findings of Phases 1 and 2. Four intervention elements were specified for the SL implementation framework. The first intervention element focused on the assessment of readiness for SL institutionalisation. The development of SL capacity and SL scholarship was regarded as the pivotal intervention element for three of the elements: the development of a contextual SL definition, an SL pedagogical model, and a monitoring and evaluation system for SL institutionalisation.Conclusion: The SL implementation framework satisfies the goals of SL institutionalisation, namely to develop a common language and a set of principles to guide practice, and to ensure the allocation of resources in order to facilitate the SL teaching methodology.The contextualised SL definition that was formulated for the SoN contributes to the SL operationalisation discourse at the HEI.
Unshackling the Church
Authors: Vellem Vuyani
Published: November 2015

In whose ‘order’, ‘newness’ and ‘foundation’ is ecclesiology based in South Africa? The colonial legacy of pigmentocracy, the cultural domination and annihilation of the indigenous dispensation of black Africans, is not devoid of institutional structures of faith and their historical performance in South Africa. The church is one institution in South Africa that played a crucial role in perpetrating perversities of racial, economic and cultural exclusion with a fetish of its institutional character that is still pervasive and dangerously residual in post-1994 South Africa. By presenting a brief outline of the basics on ecclesiology, the article argues that things remain the same the more things seem to change if the methodological approach to ecclesiology circumvents the edifice and foundations on which the history of ecclesiology in South Africa is built. To unshackle the church, a Black Theology of liberation must begin from and debunk the foundations of models of ecclesiology that are conceived on perverse theological and ideologised forms of faith that have become residually hazardous in South Africa post-1994.
Shape Control of Anodic Aluminum Oxide and Effect as Support of Silicon Powder Electrode
Authors: Song Ju-Seok , Ha Jong-Keun , Kim Yoo-Young , Park Dong-Kyu , Ahn In-Shup , Ahn Jou-Hyeon , Cho Kwon-Koo
Published: November 2015

Anodic aluminum oxide (AAO) has been widely used for the development and fabrication of nano-powder with various morphologies such as particle, wire, rod, and tube. So far, many researchers have reported about shape control and fabrication of AAO films. However, they have reported on the shape control with different diameter and length of anodic aluminum oxide mainly. We present a combined mild-hard (or hard-mild) anodization to prepare shape-controlled AAO films. Two main parameters which are combination mild-hard (or hard-mild) anodization and run-time of voltage control are applied in this work. The voltages of mild and hard anodization are respectively 40 and 80 V. Anodization was conducted on the aluminum sheet in 0.3 mole oxalic acid at 4°C. AAO films with morphologies of varying interpore distance, branch-shaped pore, diameter-modulated pore and long funnel-shaped pore were fabricated. Those shapes will be able to apply to fabricate novel nano-materials with potential application which is especially a support to prevent volume expansion of inserted active materials, such as metal silicon or tin powder, in lithium ion battery. The silicon powder electrode using an AAO as a support shows outstanding cycle performance as 1003 mAh/g up to 200 cycles.
Atomistic Simulation of Sintering Mechanism for Copper Nano-Powders
Authors: Seong Yujin , Hwang Sungwon , Kim See Jo , Kim Sungho , Kim Seong-Gon , Kim Hak Jun , Park Seong Jin
Published: November 2015

The sintering mechanisms of nanoscale copper powders have been investigated. A molecular dynamics (MD) simulation with the embedded-atom method (EAM) was employed for these simulations. The dimensional changes for initial-stage sintering such as characteristic lengths, neck growth, and neck angle were calculated to understand the densification behavior of copper nano-powders. Factors affecting sintering such as the temperature, powder size, and crystalline misalignment between adjacent powders have also been studied. These results could provide information of setting the processing cycles and material designs applicable to nano-powders. In addition, it is expected that MD simulation will be a foundation for the multi-scale modeling in sintering process.
Preparation of Spherical Cobalt Fine Powders by New Liquid Reduction Method
Authors: Kim Dae Weon , Kim Ji-Hoon , Choi Yo-Han , Choi Hee Lack , Yoon Jin-Ho
Published: November 2015

Spherical fine cobalt powders were fabricated by new liquid reduction method. Commercial cobalt sufate heptahydrate was used as raw material. Also ethylene glycol was used as solvent and hydrazine-sodium hypophosphite mixture was used as reduction agent for the new liquid reduction method. A plate shaped cobalt powders with an approximately 300 nm were prepared by a traditional wet ruduction method using distilled water as solvent and hydrazine. Spherical fine cobalt powders with an average size of 1-3 μm were synthesized by a new liquid reduction method in 0.3M cobalt sulfate and 1.5M hydrazine-0.6M sodium hypophosphite mixture at 333K.
Synthesis of NiTi Alloy Powder by the Reaction of NiO-TiH2 Mixing Powders
Authors: Jeon Ki Cheol , Lee Han-Eol , Yim Da-Mi , Oh Sung-Tag
Published: November 2015

The synthesis of NiTi alloy powders by hydrogen reduction and dehydrogenation process of NiO and TiH2 powder mixtures is investigated. Mixtures of NiO and TiH2 powders are prepared by simple mixing for 1 h or ball milling for 24 h. Simple-mixed mixture shows that fine NiO particles are homogeneously coated on the surface of TiH2 powders, whereas ball milled one exhibits the morphology with mixing of fine NiO and TiH2 particles. Thermogravimetric analysis in hydrogen atmosphere reveals that the NiO and TiH2 phase are changed to metallic Ni and Ti in the temperature range of 260 to 290°C and 553 to 639°C, respectively. In the simple-mixed powders by heat-up to 700°C, agglomerates with solid particles and solidified liquid phase are observed, and the size of agglomerates is increased at 1000°C. From the XRD analysis, the presence of liquid phase is explained by the formation and melting of NiTi2 intermetallic compound due to an exothermic reaction between Ni and Ti. The simple-mixed powders, heated to 1000°C, lead to the formation of NiTi phase but additional Ni-, Ti-rich and Ti-oxide phases. In contrast, the microstructure of ball-milled powders is characterized by the neck-grown particles, forming Ni3Ti, Ti-oxide and unreacted Ni phase.
Influence of Oxidation Temperatures on the Structure and the Microstructure of GaN MOCVD Scraps
Authors: Hong Hyun Seon , Ahn Joong Woo
Published: November 2015

The GaN-powder scrap generated in the manufacturing process of LED contains significant amounts of gallium. This waste can be an important resource for gallium through recycling of scraps. In the present study, the influence of annealing temperatures on the structural properties of GaN powder was investigated when the waste was recycled through the mechanochemical oxidation process. The annealing temperature varied from 200°C to 1100°C and the changes in crystal structure and microstructure were studied. The annealed powder was characterized using various analytical tools such as TGA, XRD, SEM, and XRF. The results indicate that GaN structure was fully changed to Ga2O3 structure when annealed above 900°C for 2 h. And, as the annealing temperature increased, crystallinity and particle size were enhanced. The increase in particle size of gallium oxide was possibly promoted by powder-sintering which merged particles to larger than 50 nm.
The Reign of Evil in Ben Okri’s The Famished Road
Authors: Ikechi Emeka
Published: November 2015

This paper discusses reign of evil in Ben Okri’s The Famished Road. The novel reveals various levels and degrees of evil perpetrated by human beings and other forces against the weak and downtrodden in the society. In this work, moral delinquencies are presented and episodes and instances of moral decadence highlighted. An analysis of the experiences of the characters of the story is also uncovered. Findings show a society plagued by vices where the poor and the weak are at the mercy of the powerful represented by Madame Koto, politicians and other supernatural forces. It is a society struggling under the grip of one evil or the other. In criticizing moral laxity in the society as represented in Okri’s The Famished Road, we recommend a just, egalitarian and morally upright society, devoid of the display of excessive power which characterises the society under reference.
L’excision et conséquences: Une lecture womaniste de Tu t’Appelleras Tanga de Calixthe Beyala
Authors: Muotoo Chukwunonso Hyacinth , Balogun LI
Published: November 2015

En Afrique traditionnelle, la femme est vue comme un être sans voix. Elle est susceptible à toutes sortes d’exploitation et d’oppression. Elle est dépersonnalisée et abandonnée. L’excision est un des sujets traités par les écrivaines africaines dans leurs oeuvres et dont la femme est victime. C’est une pratique douloureuse qui traumatise psychologiquement et physiquement les victimes. C’est une pratique barbare et qui pose des dangers chez les femmes. Cette étude vise à critiquer l’excision qui est une des pratiques qui rongent la société africaine. C’est une pratique dégradante et oppressive. Calixthe Beyala étant  écrivaine, critique et cherche à fustiger certaines institutions patriarcales qui font obstacle à  l’émancipation et à l’épanouissement de la femme africaine dont l’excision fait partie. Cette étude  s’appuiera sur la théorie womaniste surtout celle de Chikwenye Okonjo Ogunyemi pour qu’on puisse faire une analyse profonde du sujet en question.In the traditional Africa, the woman is seen as a being without voice. She is prone to all sorts of exploitation and oppression. She is depersonalised and abandoned. Excision is one of the topics treated by the African writers of which the woman is a victim. It is a painful practice that psychologically and physically traumatises the victims. It is a barbaric practice which poses danger to women. The aim of this study is to criticise excision which is a practice that corrodes the African society. It is a degrading and an oppressive practice. Calixthe Beyala, being a writer criticises and thrashes certain patriarchal institutions that are obstacles to the emancipation and the growth of the African woman of which excision is one of them. This study will hinge on the theory of womanism especially that of Chikwenye Okonjo Ogunyemi with a view to making a deep analysis of the subject in question.
African Culture and Communication Systems in the Coronation of Ata Igala, North- Central Nigeria
Authors: Ottah Gabriel Alhassan
Published: November 2015

African culture cannot be detached from the mode of communication of Africans. In this study, the writer examined the aspects of African culture communicated during the coronation of the 27th Ata Igala of Kogi State, North-central Nigeria. The study was motivated by the fact that the Ata, Idakwo Michael Ameh Oboni, rather than modernize his installation, went back to the olden-day practice of coronation rites. It therefore became a re-enactment of African culture in Igala land, which called for investigation on its semblance with the patterns of communication in the distant past. Using ethnographic approach, the researcher employed participant observation and interviewing to understand the process and how it communicated African culture. The study revealed that the coronation had an extensive use of African communication systems in the exercise. Those traditional modes of communication are still very effective and can be properly harnessed into a platform for cultural communication among the elite. The study therefore recommends that other African nations should imbibe the cultures of their fore-fathers, the modern technology and media imperialism not withstanding, because they reflect the true identity of the African generation. It also recommends that the mass media should be used in championing the African culture, transmitting them and showcasing their richness.Key words: African Communication, African Culture, Ata Igala, Coronation,
A Political Analysis of the August 9, 2014 Gubernatorial Election in Osun State, South West Nigeria
Authors: Egwemi Victor
Published: November 2015

The August 9, 2014 gubernatorial election in Osun state, South West Nigeria was significant in many  ways. It was the second in the series of major elections before the 2015 general elections. Coming on the heels of the June 21, 2014 gubernatorial election in Ekiti state it provided an opportunity for the two major  political parties in the country the Peoples Democratic Party (PDP) and the All Progressive Congress  (APC) to test their electoral strength once again. In Ekiti the PDP was victorious and there was much talk  about the Osun election also going the way of the PDP. As it turned out, the Osun election was won by the APC and there are major lessons to be taken from the election. Among other things, it is clear that when elections are keenly contested, the political parties and their candidates go the extra mile to woo the  electorates. The ultimate gainers in such a scenario are the people because it is they that decide the  outcome. As a corollary, the country’s democracy is strengthened. While there have been complains  about the militarization of the election, this paper is of the opinion that it was the so-called militarization that led to the success recorded in the election. The paper advocates that the country needs to build on  the successes recorded in the Osun election to make future elections in the country even better. It  strongly recommends staggered elections for the country so that adequate men and materials can be  mobilized for elections in the country as was the case in the Ekiti and Osun elections.Key words: Political Analysis, Gubernatorial, Election, Osun, Nigeria
Competencies Required of Secretaries to Manage Records Life Cycle in Government Offices in Anambra State, Nigeria
Authors: Ile Chika Madu , Oguejiofor Chinwe Sussan
Published: November 2015

This study determined basic records life cycle management competencies required by secretaries in offices. The population was 298 secretaries. Structured questionnaire was used. The instrument was validated by three experts. Its internal consistency was determined using Cronbach Alpha and the result was a high  reliability coefficient of 0.75. Data collected were analysed using mean and standard deviation, while t-test was used to test the null hypothesis. The findings of the study showed, that secretaries require all the basic records lifecycle competencies identified by this study. Based on the findings, some recommendations were made including that the training institutions should ensure that they incorporate into their curriculum offerings to prepare graduates for management of records in offices.
Effectiveness of Counselllng in the adjustment of Delinquent Students in Secondarv Schools in Anambra State
Authors: Egenti Uju P
Published: November 2015

Delinquency is one of the serious challenges that face secondary schools in Anambra State. The purpose of this study therefore was to ascertain the effectiveness of counselling in the adjustment of delinquents in secondary schools in Anambra State. It is a descriptive survey guided by one research question and the hypothesis. The population of the study comprised two hundred and fifty-one (251) counsellors in the 251 government-owned secondary schools in the State. The entire population was studied. A researcher-developed instrument duly validated by experts and whose reliability index was 0.81 was used in data collection. The researcher with the help of assistants administered the instrument. Mean scores and z-test were used in data analysis. It was among others found that counselling is effective in helping delinquent students adjust in the areas of provision of services in schools to help delinquents learn basic values for their socialization. One of the   recommendations is that counselors should make counselling effective in terms of providing information to the delinquent regarding vocational training of the delinquents to ease their adjustment in school.Key words: Counselling, Adjustment, Delinquency
Women Historiography: A Tool for Global Peace
Authors: Dike Evelyn Obiageli
Published: November 2015

Women have been more commonly known by their peaceful nature. This quality is indispensable in all peace pursuits and engagements. The importance of history in the propagation of this is undisputable. It will serve as an encourager of the attributes and styles which women have been known for. In this era of women liberation and gender streamlining, it is very urgent that the sterling qualities of women be safeguarded jealously. This can only come about through good historical education. Women possess salient qualities of patience, dialogue and cooperation; all constituting inalienable tools for peace. The neglect and lack of appreciation of these  qualities in this increasingly self-seeking globe is a short cut to an abandonment of these qualities. This paper reveals how the above qualities aided the victory of the Biafran side of the war, where economic blockade as a war tool would have decimated the entire aspiring Republic. While women did not mainly handle the nozzles of guns or tanks, their activities culminated in the preservation and safeguarding of lives. This role cannot be  underestimated in all factual accounts of the journey to peace after the monster of engagement in war; after  all, where is the victory of an army general who loses his entire troops in the battle ground?Key Words: Peace; Patience; Dialogue; Cooperation The hand that cuddles more likely will preserve even in adverse circumstances.
Impact of emission controls on air quality in Beijing during APEC 2014: lidar ceilometer observations
Authors: Tang G. , Zhu X. , Hu B. , Xin J. , Wang L. , Münkel C. , Mao G. , Wang Y.
Published: November 2015

Abstract. The implementation of emission reductions during the 2014 Asia-Pacific Economic Cooperation (APEC) summit provides a valuable opportunity to study air pollution in Beijing. From 15 October to 30 November 2014, the height of the atmospheric mixing layer and the vertical attenuated backscattering coefficient profiles were observed online using a~lidar ceilometer. Compared with fine particulate matter (PM2.5) and aerosol optical depth (AOD) data, the attenuated backscattering coefficients measured by the lidar ceilometer were strongly correlated with the PM2.5 concentration and AOD (correlation coefficients of 0.89 and 0.86, respectively). This result demonstrated the reliability of the vertical distribution of particles measured by the lidar ceilometer. By classifying different degrees of air pollution based on visibility, we found that during the transition period of air pollution, which was affected by transport of southerly flows in the mixing layer, the attenuated backscattering coefficient from 0 to 1500 m was enhanced by approximately 1.4 Mm−1 sr−1 (140 %). During the polluted period, the attenuated backscattering coefficient from 0 to 300 m suddenly increased, and the coefficient near the surface peaked (approximately 14 Mm−1 sr−1); however, the attenuated backscattering coefficient from 300 to 900 m decreased gradually, and the average value from 0 to 1500 m decreased by 0.5 Mm−1sr−1 (20 %). The height of the mixing layer gradually decreased, and the ratio of CO / SO2 gradually increased, which indicate that the polluted period was dominated by local contribution. Due to the emission reductions during APEC (DAPEC), the concentration of PM2.5 decreased by 59.2 and 58.9 % and visibility improved by 70.2 and 56.0 % compared to before (BAPEC) and after APEC (AAPEC), respectively. The contribution of regional transport in DAPEC decreased by approximately 36 and 25 %, and the local contribution decreased by approximately 48 and 54 % compared to BAPEC and AAPEC, respectively. The most effective method of controlling air pollution in the Beijing area is to reduce regional emissions during the transition period and reduce local emissions during the polluted period.
Tropospheric Ozone Variability during the East Asian Summer Monsoon as Observed by Satellite (IASI), Aircraft (MOZAIC) and Ground Stations
Authors: Safieddine S. , Boynard A. , Hao N. , Huang F. , Wang L. , Ji D. , Barret B. , Ghude S. D. , Coheur P.-F. , Hurtmans D. , Clerbaux C.
Published: November 2015

Abstract. Satellite measurements from the thermal Infrared Atmospheric Sounding Interferometer (IASI), the Measurements of OZone and water vapor by in-service AIrbus airCraft (MOZAIC), as well as observations from ground based stations, are used to assess the tropospheric ozone (O3) variability during the East Asian Summer Monsoon (EASM). Six years [2008–2013] of IASI data analysis reveals the ability of the instrument to detect the onset and the progression of the monsoon reflected by a decrease in the tropospheric [0–6] km O3 column due to the EASM, and to reproduce this decrease from one year to the other. Focusing on the period of May–August 2011, taken as an example year, IASI data show clear inverse relationship between tropospheric [0–6] km O3 on one hand and meteorological parameters such as cloud cover, relative humidity and wind speed, on the other hand. Aircraft data from the MOZAIC project at Hyderabad, Nanjing and Guangzhou are used to validate the IASI data and to assess the effect of the monsoon on the vertical distribution of the tropospheric O3 at different locations. Results show good agreement with a correlation coefficient of 0.74 between the [0–6] km O3 column derived from IASI and MOZAIC. The aircraft data show a decrease in the tropospheric O3 that is more important in the free troposphere than in the boundary layer and at Hyderabad than at the other two Chinese cities. Ground station data at different locations in India and China show a spatiotemporal dependence on meteorology during the monsoon, with decrease up to 22 ppbv in Hyderabad, and up to 5 ppbv in the North China Plain.
Aqueous-phase mechanism for secondary organic aerosol formation from isoprene: application to the Southeast United States and co-benefit of SO2 emission controls
Authors: Marais E. A. , Jacob D. J. , Jimenez J. L. , Campuzano-Jost P. , Day D. A. , Hu W. , Krechmer J. , Zhu L. , Kim P. S. , Miller C. C. , Fisher J. A. , Travis K. , Yu K. , Hanisco T. F. , Wolfe G. M. , Arkinson H. L. , Pye H. O. T. , Froyd K. D. , Liao J. , McNeill V. F.
Published: November 2015

Abstract. Isoprene emitted by vegetation is an important precursor of secondary organic aerosol (SOA), but the mechanism and yields are uncertain. Aerosol is prevailingly aqueous under the humid conditions typical of isoprene-emitting regions. Here we develop an aqueous-phase mechanism for isoprene SOA formation coupled to a detailed gas-phase isoprene oxidation scheme. The mechanism is based on aerosol reactive uptake probabilities (γ) for water-soluble isoprene oxidation products, including sensitivity to aerosol acidity and nucleophile concentrations. We apply this mechanism to simulation of aircraft (SEAC4RS) and ground-based (SOAS) observations over the Southeast US in summer 2013 using the GEOS-Chem chemical transport model. Emissions of nitrogen oxides (NOx ≡ NO + NO2) over the Southeast US are such that the peroxy radicals produced from isoprene oxidation (ISOPO2) react significantly with both NO (high-NOx pathway) and HO2 (low-NOx pathway), leading to different suites of isoprene SOA precursors. We find a mean SOA mass yield of 3.3 % from isoprene oxidation, consistent with the observed relationship of OA and formaldehyde (a product of isoprene oxidation). The yield is mainly contributed by two immediate gas-phase precursors, isoprene epoxydiols (IEPOX, 58 % of isoprene SOA) from the low-NOx pathway and glyoxal (28 %) from both low- and high-NOx pathways. This speciation is consistent with observations of IEPOX SOA from SOAS and SEAC4RS. Observations show a strong relationship between IEPOX SOA and sulfate aerosol that we explain as due to the indirect effect of sulfate on aerosol acidity and volume, rather than a direct mechanistic role for sulfate. Isoprene SOA concentrations increase as NOx emissions decrease (favoring the low-NOx pathway for isoprene oxidation), but decrease as SO2 emissions decrease (due to the effect of sulfate on aerosol acidity and volume). The US EPA projects 2013–2025 decreases in anthropogenic emissions of 34 % for NOx (leading to 7 % increase in isoprene SOA) and 48 % for SO2 (35 % decrease in isoprene SOA). The combined projected decreases in NOx and SO2 emissions reduce isoprene SOA yields from 3.3 to 2.3 %. Reducing SO2 emissions decreases sulfate and isoprene SOA by a similar magnitude, representing a factor of 2 co-benefit for PM2.5 from SO2 emission controls.
Summertime nitrate aerosol in the upper troposphere and lower stratosphere over the Tibetan Plateau and the South Asian summer monsoon region
Authors: Gu Y. , Liao H.
Published: November 2015

Abstract. We use the global three-dimensional Goddard Earth Observing System chemical transport model (GEOS-Chem) to examine the contribution of nitrate aerosol to aerosol concentrations in the upper troposphere and lower stratosphere (UTLS) over the Tibetan Plateau and the South Asian summer monsoon (TP/SASM) region during summertime of year 2005. Simulated surface-layer aerosol concentrations are compared with ground-based observations, and simulated aerosols in the UTLS are evaluated by using the Stratospheric Aerosol and Gas Experiment II satellite data. Simulations show elevated aerosol concentrations of sulfate, nitrate, ammonium, black carbon, organic carbon, and PM2.5 (particles with diameter equal or less than 2.5 μm) in the UTLS over the TP/SASM region throughout the summer. Nitrate aerosol is simulated to be the second largest aerosol species in the surface-layer but the most dominant aerosol species in the UTLS over the studied region. Averaged over summertime and over the TP/SASM region, CNIT (the ratio of nitrate concentration to PM2.5 concentration) values are 5–35 % at the surface, 25–50 % at 200 hPa, and exceed 60 % at 100 hPa. The mechanisms for the accumulation of nitrate in the UTLS over the TP/SASM region include vertical transport and the gas-to-aerosol conversion of HNO3 to form nitrate. The high relative humidity and low temperature associated with the deep convection over the TP/SASM region are favorable for the gas-to-aerosol conversion of HNO3.
The climatic imprint of bimodal distributions in vegetation cover for West Africa
Authors: Yin Z. , Dekker S. C. , van den Hurk B. J. J. M. , Dijkstra H. A.
Published: November 2015

Abstract. Observed bimodal distributions of woody cover in West Africa provide evidence that alternative ecosystem states may exist under the same precipitation regimes. Understanding the explicit climate conditions where the woody cover bimodality can exist is important to predict crucial transitions of ecosystems due to climate change. In this study, we show that bimodality can also be observed in mean annual shortwave radiation and above ground biomass. Through conditional histogram analysis, we find that the bimodality of woody cover can only exist under low mean annual shortwave radiation and low above ground biomass. Based on a land cover map, in which anthropogenic land use was removed, six climatic indicators that represent water, energy, climate seasonality and water-radiation coupling are analyzed to investigate the coexistence of these indicators with specific land cover types. From this analysis we find that the mean annual precipitation is not a sufficient predictor of a potential land cover change. Indicators of climate seasonality are strongly related to the observed land cover type. However, these indicators can only demonstrate the potential occurrence of bimodality but cannot exclude the probability of bimodal vegetation distributions. A new indicator: the normalized difference of precipitation, successfully expresses the stability of the precipitation regime and can improve the accuracy of predictions of forest states. We evaluate the land cover predictions based on different combinations of climatic indicators. Regions with high potential of land cover transitions are displayed. The results suggest that the tropical forest in the Congo basin may be unstable and shows the possibility to significantly decrease. An increase in the area covered by savanna and grass is possible, which coincides with an observed re-greening of the Sahara.
Dead zone or oasis in the open ocean? Zooplankton distribution and migration in low-oxygen modewater eddies
Authors: Hauss H. , Christiansen S. , Schütte F. , Kiko R. , Edvam Lima M. , Rodrigues E. , Karstensen J. , Löscher C. R. , Körtzinger A. , Fiedler B.
Published: November 2015

Abstract. The eastern tropical North Atlantic (ETNA) features a mesopelagic oxygen minimum zone (OMZ) at approximately 300–600 m depth. Here, oxygen concentrations rarely fall below 40 μmol O2 kg−1, but are thought to decline in the course of climate change. The recent discovery of mesoscale eddies that harbour a shallow suboxic (< 5 μmol O2 kg−1) OMZ just below the mixed layer could serve to identify zooplankton groups that may be negatively or positively affected by on-going ocean deoxygenation. In spring 2014, a detailed survey of a suboxic anticyclonic modewater eddy (ACME) was carried out near the Cape Verde Ocean Observatory (CVOO), combining acoustic and optical profiling methods with stratified multinet hauls and hydrography. The multinet data revealed that the eddy was characterized by an approximately 1.5-fold increase in total area-integrated zooplankton abundance. A marked reduction in acoustic target strength (derived from shipboard ADCP, 75kHz) within the shallow OMZ at nighttime was evident. Acoustic scatterers were avoiding the depth range between about 85 to 120 m, where oxygen concentrations were lower than approximately 20 μmol O2 kg−1, indicating habitat compression to the oxygenated surface layer. This observation is confirmed by time-series observations of a moored ADCP (upward looking, 300 kHz) during an ACME transit at the CVOO mooring in 2010. Nevertheless, part of the diurnal vertical migration (DVM) from the surface layer to the mesopelagic continued through the shallow OMZ. Based upon vertically stratified multinet hauls, Underwater Vision Profiler (UVP5) and ADCP data, four strategies have been identified followed by zooplankton in response to the eddy OMZ: (i) shallow OMZ avoidance and compression at the surface (e.g. most calanoid copepods, euphausiids), (ii) migration to the shallow OMZ core during daytime, but paying O2 debt at the surface at nighttime (e.g. siphonophores, Oncaea spp., eucalanoid copepods), (iii) residing in the shallow OMZ day and night (e.g. ostracods, polychaetes), and iv) DVM through the shallow OMZ from deeper oxygenated depths to the surface and back. For strategy (i), (ii) and (iv), compression of the habitable volume in the surface may increase prey-predator encounter rates, rendering zooplankton more vulnerable to predation and potentially making the eddy surface a foraging hotspot for higher trophic levels. With respect to long-term effects of ocean deoxygenation, we expect zooplankton avoidance of the mesopelagic OMZ to set in if oxygen levels decline below approximately 20 μmol O2 kg−1. This may result in a positive feedback on the OMZ oxygen consumption rates, since zooplankton respiration within the OMZ as well as active flux of dissolved and particulate organic matter into the OMZ will decline.
Efficient thermal infrared emitter with high radiant power
Authors: Ott T. , Schossig M. , Norkus V. , Gerlach G.
Published: November 2015

Abstract. Sensitive and selective gas measurements are crucial for a large variety of applications, e.g., explosion protection. Optical gas detection is usually based on the gas' absorption of infrared radiation (IR). It is the leading technique in terms of accuracy, reliability, and economic efficiency. Since most gas measurements are made in the two wavelength ranges of (3 ... 5) and (8 ... 14) μm, a broadband IR source is necessary. In this paper, we report on a novel thermal IR emitter with high radiant power and a near-blackbody emission characteristic that can be modulated electrically. The layout of the IR source had been optimized by use of finite element analyses (FEA) in order to get an adequate electrical resistance as well as a homogeneous temperature distribution and a minimum deflection of the radiating element. Due to its excellent thermal isolation from the heat sink, the electrical power consumption is very low. Operating temperatures of up to 1400 K are possible, so that the fabricated IR source features a very high radiant power. Its application in gas analysis will improve the performance and efficiency of gas measurement systems.
Smartphone applications for communicating avalanche risk information – a review of existing practices
Authors: Charrière M. K. M. , Bogaard T. A.
Published: November 2015

Abstract. Every year, in all mountainous regions, people are victims of avalanches. One way to decrease those losses is believed to be informing about danger levels. The paper presents a study on current practices in the development of smartphones applications that are dedicated to avalanche risk communication. The analysis based on semi-structured interviews with developers of smartphone apps highlights the context of their development, how choices of content and visualization were made as well as how their effectiveness is evaluated. It appears that although the communicators agree on the message to disseminate, its representation triggers debate. Moreover, only simple evaluation processes are conducted but there is a clear awareness that further scientific efforts are needed to analyze the effectiveness of the smartphone apps. Finally, the current or planned possibility for non-experts users to report feedback on the snow and avalanches conditions open the doors to a transition of these apps from one-way communication tools to two-ways communication platforms. This paper also indicates the remaining challenges that avalanche risk communication is facing, although it is disputably the most advanced and standardized practice compared to other natural hazards. Therefore, this research is of interest for the entire field of natural hazards related risk communication.
Compensation between meridional flow components of the AMOC at 26° N
Authors: Frajka-Williams E. , Meinen C. S. , Johns W. E. , Smeed D. A. , Duchez A. , Lawrence A. J. , Cuthbertson D. A. , McCarthy G. D. , Bryden H. L. , Moat B. I. , Rayner D.
Published: November 2015

Abstract. From ten years of observations of the Atlantic meridional overturning circulation at 26° N (MOC, 2004–2014), we revisit the question of flow compensation between components of the circulation. Contrasting with early results from the observations, transport variations of the Florida Current (FC) and upper mid-ocean transports (UMO, top 1000 m east of the Bahamas) are now found to compensate on sub-annual timescales. A deep baroclinic response to wind-forcing (Ekman transport) is also found in the lower North Atlantic Deep Water (LNADW, 3000–5000 m) transport. The observed compensation between the FC and UMO transports is associated with horizontal circulation and means that their individual variability does not project onto the MOC. In contrast, covariability between Ekman and the LNADW transports does contribute to overturning. On longer timescales, the southward UMO transport has continued to strengthen, resulting in a continued decline of the MOC. Most of this interannual variability of the MOC can be traced to changes in isopycnal displacements on the western boundary, within the top 1000 m and below 2000 m. Substantial trends are observed in isopycnal displacements in the deep ocean, underscoring the importance of deep boundary measurements to capture the variability of the Atlantic MOC.
Determinants of farmers' tree planting investment decision as a degraded landscape management strategy in the central highlands of Ethiopia
Authors: Gessesse B. , Bewket W. , Bräuning A.
Published: November 2015

Abstract. Land degradation due to lack of sustainable land management practices are one of the critical challenges in many developing countries including Ethiopia. This study explores the major determinants of farm level tree planting decision as a land management strategy in a typical framing and degraded landscape of the Modjo watershed, Ethiopia. The main data were generated from household surveys and analysed using descriptive statistics and binary logistic regression model. The model significantly predicted farmers' tree planting decision (Chi-square = 37.29, df = 15, P<0.001). Besides, the computed significant value of the model suggests that all the considered predictor variables jointly influenced the farmers' decision to plant trees as a land management strategy. In this regard, the finding of the study show that local land-users' willingness to adopt tree growing decision is a function of a wide range of biophysical, institutional, socioeconomic and household level factors, however, the likelihood of household size, productive labour force availability, the disparity of schooling age, level of perception of the process of deforestation and the current land tenure system have positively and significantly influence on tree growing investment decisions in the study watershed. Eventually, the processes of land use conversion and land degradation are serious which in turn have had adverse effects on agricultural productivity, local food security and poverty trap nexus. Hence, devising sustainable and integrated land management policy options and implementing them would enhance ecological restoration and livelihood sustainability in the study watershed.
A Smart Way of Coping with Common Core Challenges - Introduction to CAFA SmartWorkbook
Authors: Choi Jaehwa , Kang Miseon , Kim Najung , Dardick William , Zhang Xinxin
Published: November 2015

The Common Core State Standards (CCSS) in mathematics are currently adopted in most U.S. states. Nonetheless, most math teachers across the country are still experiencing difficulties in putting these standards into practice. Teachers and local school administrators are faced with a challenge of adapting methodologies in instruction and assessment to ensure that students master the knowledge and skills required in the new standards. This leads to an urgent need for well-designed teaching and assessment tools for math education that are aligned to the CCSS.

The purpose of this paper is to illustrate the Computer Adaptive Formative Assessment (CAFA) SmartWorkbook which is an Information and Communication Technology (ICT) based teaching and assessment tool specially designed for coping with challenges in implementing the CCSS in mathematics. The CAFA SmartWorkbook represents a new stage in exploring opportunities in educational innovation, capitalizing on advances in assessment and technology. This system can be an effective solution to cope with CCSS challenges in both theoretical and practical points of view for students, teachers, parents, and educational administrators.
Surviving Recognition and Racial In/justice
Authors: Hesford Wendy S.
Published: November 2015

Scholars across the disciplines have turned to theories of recognition to interpret recent cases of racial profiling, police brutality, and the militarization of the police in black communities. Social activists, too, have embraced the concept, staging recognition scenes to claim political legitimacy. I examine the rhetorical contours of five recognition scenes and the sociopolitical objectives that recognition is expected to perform: 1) dialectical recognitions, which showcase how recognition works hierarchically through dyadic configurations of structural inequalities; 2) intersectional recognitions, which break down the oppressor/oppressed binary through multiaxle identifications and analyses; 3) human rights recognitions, which attempt to hold liberalism accountable to its ideals; 4) recognitions in between, which draw attention to the limits of classical liberal and neoliberal logics of recognition and create alliances that may be impossible based on the logics of recognition; and 5) postracial recognitions, which invest in the temporal fantasy that race is no longer a structuring principle in inequality and fail to account for the power in which recognition operates.
Recognition in Blue
Authors: Charland Maurice
Published: November 2015

Gerald Early's remark that black people are seminally important to the modern world because they created the blues is examined as a contribution to the politics of recognition that deviates from the liberal model that dominates in political theory. Central to this deviation is the politics of honor and Paul Corcoran's distinction between formal and aesthetic recognition. The politics of aesthetic recognition is examined here through Hans-Georg Gadamer's discussion of hermeneutics in Truth and Method as well as through Martin Heidegger's phenomenology and philosophy of Dasein (being-there), inspired by Aristotle's Rhetoric, and his writings on art. The significance of art and specifically of the blues to the politics of recognition goes beyond the representation or the relaying of others' voices, in that it calls forth modes of being-there over against difference.
A Defense of the “Monstrous” Animals of Pliny, Aelian, and Others
Authors: Kitchell Kenneth F.
Published: November 2015

It is customary to criticize ancient and medieval authors on animal lore for being gullible and repeating any story no matter how incredible. This article seeks to mitigate this criticism by pointing out four factors that are often overlooked by such critics. First, a great number of the stories are based on real facts that became distorted through misobservation or because such stories often traveled vast distances on their way to Greek and Roman authors. Seven examples, from stories ranging from the self-castrating beavers to a blood-sucking moth, provide evidence of these processes. Moreover, we must consider the ancients' inherent awe before nature, an attitude that was supported and augmented by mirabilia displayed by conquerors of far-off places. Finally, reverence for previous authors and a faith-based agenda are adduced for the Middle Ages.
Superstition, Testimony, and the Eighteenth-Century Vampire Debates
Authors: Morris Kathryn
Published: November 2015

In the late seventeenth century, reports of vampire attacks began to emerge out of eastern Europe. These stories became the focus of a scholarly debate that centered on whether the events described in the vampire reports could possibly be true and, if so, how they ought to be explained. The reports presented a dilemma: although the events they described were implausible, the reports were often supported by testimony from reliable sources. This article will explore two eighteenth-century interventions in the vampire debate, and consider how they responded to this tension. Augustin Calmet carefully documented and examined the vampire reports, using established natural philosophical models for the study of strange phenomena. Despite Calmet's rational methods and skeptical conclusions, his work on vampires was vociferously attacked by Voltaire. I will argue that the encounter between Calmet and Voltaire illustrates their different ways of understanding the relationship among superstition, knowledge-production, and testimony.
As the Crow Flies
Authors: Sammond Nicholas
Published: November 2015

How are the celebrity body, the voice, and race related to each other? This essay examines the career of the popular early twentieth-century American blackface minstrels Moran and Mack. It charts their rise across a range of media platforms and (for one of them) through more than one body, discussing how the figure of the minstrel reveals through its fungibility the raced nature of celebrity and the longstanding historical relationship between racial formations and performing commodities.