bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of Ochratoxin A and Its Thermal Degradation Product 2′R-Ochratoxin A with Human Serum Albumin
Authors: Sueck Franziska , Poór Miklós , Faisal Zelma , Gertzen Christoph G. W. , Cramer Benedikt , Lemli Beáta , Kunsági-Máté Sándor , Gohlke Holger , Humpf Hans-Ulrich
Published: June 2018

Ochratoxin A (OTA) is a toxic secondary metabolite produced by several fungal species of the genus Penicillium and Aspergillus. 2′R-Ochratoxin A (2′R-OTA) is a thermal isomerization product of OTA formed during food processing at high temperatures. Both compounds are detectable in human blood in concentrations between 0.02 and 0.41 µg/L with 2′R-OTA being only detectable in the blood of coffee drinkers. Humans have approximately a fifty-fold higher exposure through food consumption to OTA than to 2′R-OTA. In human blood, however, the differences between the concentrations of the two compounds is, on average, only a factor of two. To understand these unexpectedly high 2′R-OTA concentrations found in human blood, the affinity of this compound to the most abundant protein in human blood the human serum albumin (HSA) was studied and compared to that of OTA, which has a well-known high binding affinity. Using fluorescence spectroscopy, equilibrium dialysis, circular dichroism (CD), high performance affinity chromatography (HPAC), and molecular modelling experiments, the affinities of OTA and 2′R-OTA to HSA were determined and compared with each other. For the affinity of HSA towards OTA, a logK of 7.0–7.6 was calculated, while for its thermally produced isomer 2′R-OTA, a lower, but still high, logK of 6.2–6.4 was determined. The data of all experiments showed consistently that OTA has a higher affinity to HSA than 2′R-OTA. Thus, differences in the affinity to HSA cannot explain the relatively high levels of 2′R-OTA found in human blood samples.
Variations of the Energy of Free Particles in the pp-Wave Spacetimes
Authors: Maluf José Wadih , Da Rocha-Neto José Francisco , Ulhoa Sérgio C. , Carneiro Fernando L.
Published: June 2018

We consider the action of exact plane gravitational waves, or pp-waves, on free particles. The analysis is carried out by investigating the variations of the geodesic trajectories of the particles, before and after the passage of the wave. The initial velocities of the particles are non-vanishing. We evaluate numerically the kinetic energy per unit mass of the free particles and obtain interesting, quasi-periodic behavior of the variations of the kinetic energy with respect to the width λ of the Gaussian that represents the wave. The variation of the energy of the free particle is expected to be exactly minus the variation of the energy of the gravitational field, and therefore provides an estimation of the local variation of the gravitational energy. The investigation is carried out in the context of short bursts of gravitational waves, and of waves described by normalized Gaussians, that yield impulsive waves in a certain limit.
Tick-Borne Flaviviruses and the Type I Interferon Response
Authors: Lindqvist Richard , Upadhyay Arunkumar , Överby Anna K.
Published: June 2018

Flaviviruses are globally distributed pathogens causing millions of human infections every year. Flaviviruses are arthropod-borne viruses and are mainly transmitted by either ticks or mosquitoes. Mosquito-borne flaviviruses and their interactions with the innate immune response have been well-studied and reviewed extensively, thus this review will discuss tick-borne flaviviruses and their interactions with the host innate immune response.
Nonstationary Flood Frequency Analysis Using Univariate and Bivariate Time-Varying Models Based on GAMLSS
Authors: Zhang Ting , Wang Yixuan , Wang Bing , Tan Senming , Feng Ping
Published: June 2018

With the changing environment, a number of researches have revealed that the assumption of stationarity of flood sequences is questionable. In this paper, we established univariate and bivariate models to investigate nonstationary flood frequency with distribution parameters changing over time. Flood peak Q and one-day flood volume W1 of the Wangkuai Reservoir catchment were used as basic data. In the univariate model, the log-normal distribution performed best and tended to describe the nonstationarity in both flood peak and volume sequences reasonably well. In the bivariate model, the optimal log-normal distributions were taken as marginal distributions, and copula functions were addressed to construct the dependence structure of Q and W1. The results showed that the Gumbel-Hougaard copula offered the best joint distribution. The most likely events had an undulating behavior similar to the univariate models, and the combination values of flood peak and volume under the same OR-joint and AND-joint exceedance probability both displayed a decreasing trend. Before 1970, the most likely combination values considering the variation of distribution parameters over time were larger than fixed parameters (stationary), while it became the opposite after 1980. The results highlight the necessity of nonstationary flood frequency analysis.
Efficiency Assessment of Existing Pumping/Hydraulic Network Systems to Mitigate Flooding in Low-Lying Coastal Regions under Different Scenarios of Sea Level Rise: The Mazzocchio Area Study Case
Authors: Cioffi Francesco , De Bonis Trapella Alessandro , Conticello Federico
Published: June 2018

Rising of the sea level and/or heavy rainfall intensification significantly enhance the risk of flooding in low-lying coastal reclamation areas. Therefore, there is a necessity to assess whether channel hydraulic networks and pumping systems are still efficient and reliable in managing risks of flooding in such areas in the future. This study addresses these issues for the pumping system of the Mazzocchio area, which is the most depressed area within the Pontina plain, a large reclamation region in the south of Lazio (Italy). For this area, in order to assess climate change impact, a novel methodological approach is proposed, based on the development of a simulation–optimization model, which combines a multiobjective evolutionary algorithm and a hydraulic model. For assigned extreme rainfall events and sea levels, the model calculates sets of Pareto optimal solutions which are obtained by defining two optimality criteria: (a) to minimize the flooding surface in the considered area; (b) to minimize the pumping power necessary to mitigate the flooding. The application shows that the carrying capacity of the hydraulic network downstream of the pumping system is insufficient to cope with future sea level rise and intensification of rainfall.
Changes in the Carbon and Water Fluxes of Subtropical Forest Ecosystems in South-Western China Related to Drought
Authors: Zhou Lei , Wang Shaoqiang , Chi Yonggang , Ju Weimin , Huang Kun , Mickler Robert A. , Wang Miaomiao , Yu Quanzhou
Published: June 2018

Drought impacts carbon and water fluxes of terrestrial ecosystems, which are strongly coupled. However, the magnitudes of response of carbon and water fluxes to drought are dependent on many processes, which are more complex than previously expected. Southern China experienced regional climatic perturbation events in the past decade and a two-year drought in 2009–2010. We used a terrestrial ecosystem model coupled with remotely sensed observations and metrological data to simulate the variations of net primary productivity (NPP), evapotranspiration (ET), and water-use efficiency (WUE) (i.e., NPP/ET) in south-western China during the period 2001–2010. Using the standard precipitation index (SPI) classifying different drought stresses, we also quantified the effect of drought on the ecosystem by comparing changes in modelled estimates of monthly WUE, NPP and ET under normal (i.e., baseline) and drought conditions (i.e., 2009 and 2010). The results indicated that NPP and ET showed synchronized declines in drought periods, with time-lag effects. Furthermore, drought-induced NPP decline was larger than ET reduction. An increasing trend in WUE from the moderate to extreme drought classes occurred not only in baseline conditions but also in drought conditions. Especially in the extreme drought period (January, 2010), WUE for the forest ecosystem typically showed a positive response to drought, indicating a drought-resilient forest ecosystem. Our study has important implications for understanding climate extreme effects on the carbon and water cycle of the forest ecosystem.
The Influences of a Clay Lens on the Hyporheic Exchange in a Sand Dune
Authors: Lu Chengpeng , Yao Congcong , Su Xiaoru , Jiang Yong , Yuan Feifei , Wang Maomei
Published: June 2018

A laboratory flume simulating a riverbed sand dune containing a low-permeability clay lens was constructed to investigate its influence on the quality and quantity of hyporheic exchange. By varying the depths and spatial locations of the clay lens, 24 scenarios and one blank control experiment were created. Dye tracers were applied to visualize patterns of hyporheic exchange and the extent of the hyporheic zone, while NaCl tracers were used to calculate hyporheic fluxes. The results revealed that the clay lens reduces hyporheic exchange and that the reduction depends on its spatial location. In general, the effect was stronger when the lens was in the center of the sand dune. The effect weakened when the lens was moved near the boundary of the sand dune. A change in horizontal location had a stronger influence on the extent of the hyporheic zone compared with a change in depth. The size of the hyporheic zone changed with the depth and position of the clay lens. There was a maximum of hyporheic extent with the lens at a depth of 0.1 m caused by changes of water flow paths.
Optimization of Nitrogen Removal in Solid Carbon Source SND for Treatment of Low-Carbon Municipal Wastewater with RSM Method
Authors: Zhang Liqiu , Huang Youwen , Li Shugeng , He Peifen , Wang Dengmin
Published: June 2018

In this work, a loofah sponge was used as the solid carbon source and the carrier in a biofilm reactor. Simultaneous nitrification and denitrification (SND) technology was used to achieve nitrogen removal in low-carbon municipal wastewater in a sequencing batch biofilm reactor (SBBR). At room temperature, the effects of filling ratio, dissolved oxygen (DO), pH, C/N(CODCr/TN), and aeration time on the removal of nitrogen were systematically studied. In addition, the removal efficiency of total nitrogen (TN) was used as the evaluation index in response surface models (RSM) for optimization of nitrogen removal. The results showed that DO, pH, and aeration time affected nitrogen removal significantly. Therefore, DO, pH, and aeration time were used as the independent variables in RSM. The optimum conditions for nitrogen removal were found to be as follows in RSM: DO = 4.09 mg/L, pH = 7.58, aeration time = 10.47 h. Under the optimum conditions, the maximum TN removal efficiency reached 86.27%. The results also demonstrated that the deviation between the experimental and predicted TN removal efficiency was only 0.58%, the predicted model was reliable for future application.
Radiative Charge Transfer between the Helium Ion and Argon
Authors: Babb James F. , McLaughlin Brendan M.
Published: June 2018

The rate coefficient for radiative charge transfer between the helium ion and an argon atom is calculated. The rate coefficient is about

at 300 K in agreement with earlier experimental data.
Dynamique et diversité des armées africaines
Authors: Warner Jason , Thaler Kai M.
Published: June 2018

Dans son grand récit historique sur les armées africaines, Edgerton (2004) affirme que les armées du continent sont passées de l’honneur à l’infamie. D’autres conceptions populaires qualifient les armées africaines de « non professionnelles », « non pertinentes » et « dangereuses » (Howe, 2005). Est-ce le cas ? Et si oui, pourquoi ? Aujourd’hui, près de soixante ans après les indépendances, que savons-nous de la nature des armées africaines, de leurs évolutions et de leur position à la croisée des intérêts des États, des dirigeants, de la société civile et de l’ensemble de la communauté internationale ? Nous examinons ici l’état des connaissances et des débats sur les armées africaines, en proposant une réflexion et des exemples concrets permettant de contextualiser.
Service civique et développement au Sénégal
Authors: Tiquet Romain
Published: June 2018

En prenant le cadre de la formulation du service civique national au Sénégal, et plus précisément d’un chantier militaire organisé dans la vallée du fleuve Sénégal par le chef d’état-major Jean-Alfred Diallo, cet article analyse comment l’armée est intervenue, non pas en tant que force de maintien de l’ordre, mais en tant qu’acteur économique et social dans le développement du pays. Plus largement, le rôle joué par l’armée dans l’organisation du service civique caractérise la relation particulière qu’entretient l’institution militaire sénégalaise avec le pouvoir politique.
Les quartiers créatifs : construction de clubs de travailleurs créatifs. Analyse croisée des quartiers du Panier (Marseille) et des Olivettes (Nantes)
Authors: Michel Basile
Published: June 2018

L’agglomération spatiale d’activités culturelles et créatives (art, architecture, etc.) dans d’anciens quartiers ouvriers transforme des espaces partiellement en friche en quartiers créatifs. Ces derniers sont le lieu d’ancrage de réseaux collaboratifs de travailleurs créatifs marqués par des dynamiques collectives de partage mais aussi par une forme d’entre-soi. Afin d’éclairer les dynamiques qui façonnent les quartiers créatifs, cet article vise à tester l’hypothèse de la constitution d’un club de travailleurs créatifs au sein de ces territoires. Défini comme un regroupement volontaire d’individus autour de la jouissance exclusive de biens et de services, le club est porteur à la fois d’une logique inclusive et exclusive. Questionner son existence dans les quartiers créatifs introduit une réflexion autour du rôle joué par les travailleurs créatifs dans les dynamiques urbaines actuelles. Sur la base d’enquêtes qualitatives (168 entretiens), l’analyse des quartiers créatifs du Panier (Marseille) et des Olivettes (Nantes) montre qu’un club tend à se mettre en place dans ces territoires. Les travailleurs créatifs s’y regroupent pour bénéficier de biens et de services spécifiques. Ils contrôlent l’accès à ces ressources par des processus de sélection et de cooptation. Ils définissent un groupe exclusif de partage accessible seulement aux ayants droit.
La procession dans le Journal de Hardy : rituel religieux et objet politique
Authors: Rideau Gaël
Published: June 2018

Les cent huit mentions de processions dans le Journal de Hardy répondent à la fois à une expérience individuelle et à un souci de noter l’événement. Elles rappellent les usages, origines, rangs et parcours, mais également les troubles et accidents. La procession est à la fois reliée à la piété et à la politique. Hardy reprend les traits des récits jansénistes des cortèges en insistant sur le Saint-Sacrement. Il partage la ferveur des marches à Sainte-Geneviève. Il replace la procession dans un vocabulaire politique, par les équilibres institutionnels qu’elle donne à voir, par les réactions des spectateurs, mesure de l’opinion publique qui peut déboucher sur l’émeute. La procession prend ainsi toute sa place dans le journal comme rituel religieux, acte social et culture politique.
Ménétra dans le Paris pré-révolutionnaire et révolutionnaire (1764-1802)
Authors: Roche Daniel
Published: June 2018

Cet article propose un contre-pied à la lecture des manuscrits de Siméon Prosper Hardy (1729-1806) en interrogeant ceux de son contemporain, le vitrier Jacques Louis Ménétra (1738-1812). Croisés peut-être sur la rue Saint-Jacques ou à Saint-Cloud, Ménétra et Hardy partagèrent une époque, des espaces et des préoccupations similaires, même si l’énergie, l’observation et les pratiques d’écriture ont revêtu d’autres formes. Le Journal de ma vie et les Écrits inédits de Ménétra sont ici sollicités pour saisir l’auteur dans son appropriation de la ville, ainsi que dans ses sociabilités, ses amitiés, son travail, ses consommations et ses loisirs.
Des alternatives économiques à l’économie alternative : une histoire de l’ALDEA (1976-1989)
Authors: Duverger Timothée
Published: June 2018

L’alternative se conjugue au pluriel dans le creuset autogestionnaire de Mai 68. De « nouveaux mouvements sociaux économiques » investissent le champ économique pour y introduire des logiques extra-économiques. Des « alternatifs des campagnes » aux « alternatifs des villes », tous aspirent à inventer de nouveaux styles de vie et de nouveaux rapports sociaux. L’Agence de liaison pour le développement de l’économie alternative (ALDEA) est créée en 1981 pour les institutionnaliser. Cette étude s’intéresse à sa structuration, de ses origines à la mise en exergue de l’économie alternative comme concept fédérateur, et à ses actions, d’abord comme agence de développement, mais aussi en matière de recherche-action autour de la pluri-activité ou de participation à la naissance du mouvement altermondialiste.
On a lu pour vous – Innover à l’envers, de Christophe Midler, Bernard Jullien et Yannick Lung
Authors: Jézéquel Myriam
Published: June 2018

Voici l’histoire à succès d’un projet automobile à faible coût – la Kwid de Renault – lancé à la conquête du marché indien. Les chercheurs Christophe Midler, Bernard Jullien et Yannick Lung en relatent le processus de création sans omettre les heurts de visions au sein du groupe Renault. Une étude de cas parfaite.
Joint determination of preventive maintenance and buffer stock for a production unit under lease
Authors: Niyamosoth Thanawath , Pathumnakul Supachai
Published: June 2018

Purpose: The purpose of this work is to develop a mathematical model for simultaneously determining the optimal period of preventive maintenance actions and the optimal size of buffer stock for a production unit that is owned by a lessor and leased to a lessee under a lease contract.Design/methodology/approach: A mathematical model is formulated and a numerical procedure is developed for finding the optimal period of preventive maintenance actions and the optimal size of buffer stock to minimize the total expected costs considering both a lessor and a lessee over a lease period.Findings: The proposed model gives better solutions than those where the maintenance cost to the lessor and the production inventory cost to the lessee are minimized separately.Originality/value: The joint determination of preventive maintenance and safety stock is a topic that has been extensively studied for decades. The majority of the models reported in the literature implicitly assume that the firm owns the production unit and maintenance actions are done in-house. However, equipment acquisition through leasing is a common practice nowadays. Normally, under a lease contract, the lessor who owns the equipment is responsible for maintenance services. This may lead to a conflict between the lessor and the lessee concerning the optimal choice of maintenance actions. To solve this conflict, we propose a joint determination of preventive maintenance and safety stock model for a production unit under a lease. The objective of our model is to simultaneously determine the optimal period of preventive maintenance actions that the lessor needs to perform and the optimal size of buffer stock the lessee needs to produce so that the total combined expected costs to both parties over the lease period are minimized.
Current Order and Inventory Models in Manufacturing Environments: A Review from 2008 to 2018
Authors: Momeni Zohreh , Azizi Amir
Published: June 2018

This paper studied on supply chain in terms of order and inventory problems and factors. The extended review of this paper showed that extra costs are the most important factors in the survival of an organization and have a significant impact on company competitiveness. However, holding inventory, order acceptance, and functional risks are factors that have not been studied simultaneously. The purpose of this paper is to provide a review on critical problems and factors in order and inventory models under supply chain management. This paper selected and reviewed 56 published articles in a decade through 30 famous relevant journals which were chosen from the “Science direct and Scopus” databases. Amongst 56 articles, “International Journal of Production Economics” was ranked as the first by 11 published articles. In this regard, the applications of the Artificial Neural Network method which called “ANN”, ant colony algorithm and queue theory have been proposed. All published articles were categorized based on the author number, The first author name, publication year, problems, factors, type of manufacturing industries, research methods and results and findings. Results of this paper acknowledge that order management and inventory control can help decision makers and researchers in solving some problems in manufacturing industries.
Design and Implementation of Time Synchronization Experimental System for Wireless Sensor Networks
Authors: Sheng Tang , Jing Ke , Zunzun Li , Pengfei Dong
Published: June 2018

The basic principle of the reference broadcast synchronization protocol using in wireless sensor networks is presentï¼Œand a compact reference broadcast synchronization experimental system is designed and implemented in this paper. The experimental results show that the receivers of the system can successfully capture the timing packets issued by the broadcast beacon within 200 meters and simultaneously adjust their local clocks according the timing packets. The time synchronization error between the receivers is less than 410 microseconds. The circuit design scheme of the time synchronization experimental system proposed in this paper may be taken as technical reference for the planning and designing of low cost, miniaturization and high accuracy nodes in wireless sensor networks.
Distributed Fiber Optical Technology for Damage Identification of Engineering Structure
Authors: Dong Xiaoma , Zhou Liqiang
Published: June 2018

To conduct optical fiber monitoring rock slide model test and optical fiber monitoring of steel concrete interface slip model test, the large triaxial shear test of geotechnical engineering was used. First, the data of sliding distance and optical loss and their dynamic range were obtained. Second, the slide distance and fiber loss relation curve and the fitting equation were worked out. Finally, the typical applications of optical fiber sensing technology in Rock Engineering (high slope engineering, rock foundation of Dam Engineering) slope stability and geological disaster monitoring were put forward.The results showed that optical fiber sensing was very sensitive, and the loss value was 30 to 50dB. The dynamic range of rock slide monitoring fiber was 3 to 3.5mm, and the dynamic range of the interface slip monitoring fiber was 1.6mm. Thus, the sensing system can detect the sliding process of the interface between the concrete and the steel plate. It provides some reference for the sliding monitoring of the composite materials.
Information Security Transmission Technology in Internet of Things Control System
Authors: Zou Ying , Lv Jiezhuo
Published: June 2018

To solve the information security problem in Internet of things control system, the information security transmission technology was mainly discussed and studied, and the basic structure of networking control system was analyzed. From the main control equipment, communication equipment, control equipment, monitoring equipment, information storage device, connecting equipment and other aspects, the further research was carried out. Secondly, the structure of the Internet of things was studied, the security problems which may exist were discussed, and it was analyzed from the access security, transmission security and delays stability safety three aspects. Finally, the information security transmission technology based on the Internet of things control system was explored, and the encryption technology, authentication technology and isolation technology were analyzed in detail. The results showed that the networking control system not only had the advantages of transmission reliability, convenient interaction, and simple assembly, but also had the strengths of disperse structure, real-time data, remote monitoring and others. At last, it is summed up that the existing reliable communication resources are maximized in the transmission mechanism of the Internet of things.
Predictors of post-partum family planning uptake in Webuye Hospital, western Kenya
Authors: Owuor Henry O. , Chege Patrick M. , Laktabai Jeremiah
Published: June 2018

Background: A short inter-pregnancy interval increases the risk for maternal and neonatal deaths in addition to other pregnancy complications including: preterm delivery, low birth weight, anaemia and premature rupture of membranes. However, only one half of Kenyan women, who have no desire to conceive immediately after birth, are using contraception one year after delivery. Aim: The aim of this study was to determine the predictors of uptake of post-partum family planning (PPFP). Setting: The study was conducted among post-partum women accompanying their children for their first measles vaccination at Webuye County Hospital (WCH), in western Kenya. Methods: This was a cross-sectional study involving 259 randomly sampled post-partum women, accompanying their children for their first measles vaccination. A structured, interviewer-administered questionnaire was used to collect data. Logistic regression was used to identify correlates of PPFP uptake. Results: The uptake of PPFP among women at 9 months post-partum at WCH was found to be 78.4% ± 5.0%. The odds of PPFP uptake among women living with their sexual partners was 88.2% less than among those not living with their partners with the true population effect between 97% and 51% (OR = 0.118; 95% CI: 0.028–0.494; p = 0.003). Conclusions: Not living with her sexual partner in the same house is the key predictor of a woman’s PPFP uptake in WCH. This study recommends that any programme aimed at improving post-partum contraceptive use in WCH should target women who live with their partners in the same house.
A South African university’s readiness assessment for bringing your own device for teaching and learning
Authors: Ruxwana Nkqubela , Msibi Mncedisi
Published: June 2018

Background: The use of mobile devices for education is rapidly growing, and it is a global phenomenon. The trend of bringing personal mobile devices for learning using the institution’s network to access data and other academic material is referred to as bring your own device (BYOD). Most universities in developed countries have implemented this phenomenon to enhance education. However, the rate of BYOD adoption in developing countries is lagging even though the majority of students and staff already own one or more mobile devices and are using them for personal and educational purposes. Objectives: The study determines the readiness of a South African university to adopt BYOD for teaching and learning. Moreover, the article presents the enabling factors and barriers of BYOD adoption within the university. Method: The study followed an interpretivist philosophical stance. A qualitative single-case study was used. Data were collected through questionnaires and thematic analysis was applied. Results: The BYOD readiness levels are low and are hampered both by organisational and technological factors. Key barriers include lack of comprehensive policies to govern the use of these devices, lack of infrastructure, limited top management support for innovations and security complexities, while the key enabling factors included accessibility to mobile technologies, ease of use, relative advantage and convenience. Conclusion: Bring your own device offers a suitable platform for mobile-learning (m-learning) in universities. Consideration of the readiness factors, such as adoption strategy, implementation plans, security and device management, skills development, and measures of discipline, is essential.
A retrospective analysis of time delays in patients presenting with stroke to an academic emergency department
Authors: Khalema Diteboho , Goldstein Lara N. , Lucas Susan
Published: June 2018

Background: Stroke presents commonly to the emergency department (ED), and is a common cause of morbidity and mortality in South Africa. Early ED presentation and early neuroimaging are required in order for thrombolysis to be a potential therapeutic modality. Objectives: To determine the time to ED presentation, time to computed tomography (CT) scan and the potential influencing factors for patients with stroke. Methods: A retrospective record review of all patients who presented with clinical features of stroke to a tertiary academic ED in Johannesburg, South Africa, from 01 January to 31 December 2014. Results: Data from 232 eligible stroke patients were analysed. The median time to presentation to the ED was 33 h with the majority of patients (81.3%) presenting after the 4.5 h window for thrombolysis. The median time to CT was 8 h. Only 3.9% of patients had a CT scan within one hour of arrival. Patients with loss of consciousness were associated with earlier hospital presentation (p = 0.001). None of the patients were thrombolysed. Conclusion: Patients with stroke commonly present late to hospital. If we are to make a difference in this group of vulnerable patients, further education and training needs to be emphasised regarding ‘time is brain’. Communication and commitment is also required by the emergency medical services, ED and radiology staff in order to prioritise stroke patients and to reduce delays.
‘From History Project to Transdisciplinary Research’: District Six as a case study
Authors: Davids Mogamat N.
Published: June 2018

This article expounds how a National Research Foundation (NRF) history project evolved into a transdisciplinary study. The article develops a case in favour of transdisciplinary research as a departure from strict discipline-based inquiry. The project involves collaborative research with Master’s students and researchers located at five South African universities. The aim of this article is to evaluate the project as a transdisciplinary case study, intending to focus on its emergence as a history-based discipline, evolving into a transdisciplinary project. It also explores the epistemological value of transdisciplinary research as a knowledge production methodology in the context of the demand for a decolonised curriculum in South Africa. The article is set in the context of a NRF project with a spatiotemporal focus on the District Six forced removals during the colonial-apartheid period. A qualitative instrumental case study design guided the data collection and analyses. Participants’ project proposal texts were used as data. The results show, firstly, that transdisciplinarity is manifested in a wide range of titles and disciplines; secondly, a myriad of conceptual frameworks emerged from the data; and thirdly, a broad spectrum of research approaches emerged, mainly qualitative. Transdisciplinarity focuses on the ‘subject’ and the ‘hidden middle’ as domain where alternative philosophical research orientations are explored. Transdisciplinarity can be regarded as ‘Ubuntu’ research, given the common concern to bring out the ‘voice’ of the subaltern and a rejection of separation of humans into ‘racial’ classifications. As ‘Ubuntu research’, transdisciplinary research rejects an atomistic understanding of reality that excludes the human subject and a separation between human and nature.
Policies for decarbonizing a liberalized power sector
Authors: Newbery David
Published: June 2018

Given the agreed urgency of decarbonizing electricity and the need to guide decentralized private decisions, an adequate and credible carbon price appears essential. The paper models and quantifies the break-even carbon price for mature zero-carbon electricity investments. It appears an attractive alternative given the difficulty of measuring the social cost of carbon, but modelling shows it extremely sensitive to projected fuel prices, the rate of interest, and the capital cost of generation options, all of which are very uncertain. This has important implications, and justifies combining a carbon price floor with suitable long-term contracts for electricity investments.
Isotopic composition of daily precipitation along the southern foothills of the Himalayas: impact of marine and continental sources of atmospheric moisture
Authors: Jeelani Ghulam , Deshpande Rajendrakumar D. , Galkowski Michal , Rozanski Kazimierz
Published: June 2018

Abstract. The flow
of the Himalayan rivers, a key source of fresh water for more than a billion
people primarily depends upon the strength, behaviour and duration of the
Indian summer monsoon (ISM) and the western disturbances (WD), two
contrasting circulation regimes of the regional atmosphere. An analysis of
the 2H and 18O isotope composition of daily precipitation
collected along the southern foothills of the Himalayas, combined with
extensive backward trajectory modelling, was used to gain deeper insight into
the mechanisms controlling the isotopic composition of precipitation and the
origin of atmospheric moisture and precipitation during ISM and WD periods.
Daily precipitation samples were collected during the period from September
2008 to December 2011 at six stations, extending from Srinagar in the west
(Kashmir state) to Dibrugarh in the east (Assam state). In total, 548 daily
precipitation samples were collected and analysed for their stable isotope
composition. It is suggested that the gradual reduction in the 2H
and 18O content of precipitation in the study region, progressing
from δ18O values close to zero down to ca. −10 ‰ in
the course of ISM evolution, stems from regional, large-scale recycling of
moisture-driven monsoonal circulation. Superimposed on this general trend are
short-term fluctuations of the isotopic composition of rainfall, which might
have stem from local effects such as enhanced convective activity and the
associated higher degree of rainout of moist air masses (local amount
effect), the partial evaporation of raindrops, or the impact of isotopically
heavy moisture generated in evapotranspiration processes taking place in the
vicinity of rainfall sampling sites. Seasonal footprint maps constructed for
three stations representing the western, central and eastern portions of the
Himalayan region indicate that the influence of monsoonal circulation reaches
the western edges of the Himalayan region. While the characteristic imprint
of monsoonal air masses (increase of monthly rainfall amount) can be
completely absent in the western Himalayas, the onset of the ISM period in
this region is still clearly visible in the isotopic composition of daily
precipitation. A characteristic feature of daily precipitation collected
during the WD period is the gradual increase of 2H and
18O content, reaching positive δ2H and
δ18O values towards the end of the period. This trend can be
explained by the growing importance of moisture of continental origin as a
source of daily precipitation. High deuterium-excess (d-excess) values of
daily rainfall recorded at the monitoring stations (38 cases in total, range
from 20.6 to 44.0 ‰) are attributed to moisture of continental
origin released into the atmosphere during the evaporation of surface water
bodies and/or soil water evaporation.
Radiative impact of an extreme Arctic biomass-burning event
Authors: Lisok Justyna , Rozwadowska Anna , Pedersen Jesper G. , Markowicz Krzysztof M. , Ritter Christoph , Kaminski Jacek W. , Struzewska Joanna , Mazzola Mauro , Udisti Roberto , Becagli Silvia , Gorecka Izabela
Published: June 2018

Abstract. The aim of the presented study was to investigate the impact on the radiation
budget of a biomass-burning plume, transported from Alaska to the High Arctic
region of Ny-Ålesund, Svalbard, in early July 2015. Since the mean
aerosol optical depth increased by the factor of 10 above the average summer
background values, this large aerosol load event is considered particularly
exceptional in the last 25 years. In situ data with hygroscopic growth
equations, as well as remote sensing measurements as inputs to radiative
transfer models, were used, in order to estimate biases associated with
(i) hygroscopicity, (ii) variability of single-scattering albedo profiles,
and (iii) plane-parallel closure of the modelled atmosphere. A chemical
weather model with satellite-derived biomass-burning emissions was applied to
interpret the transport and transformation pathways. The provided MODTRAN radiative transfer model (RTM) simulations for the smoke event
(14:00 9 July–11:30 11 July) resulted in a mean aerosol
direct radiative forcing at the levels of −78.9 and −47.0 W m−2 at
the surface and at the top of the atmosphere, respectively,
for the mean value of aerosol optical depth equal to 0.64 at 550 nm. This
corresponded to the average clear-sky direct radiative forcing of −43.3 W m−2, estimated by radiometer and model simulations at the surface.
Ultimately, uncertainty associated with the plane-parallel atmosphere
approximation altered results by about 2 W m−2. Furthermore,
model-derived aerosol direct radiative forcing efficiency reached on average
−126 W m-2/τ550 and −71 W m-2/τ550 at the
surface and at the top of the atmosphere, respectively. The heating rate, estimated at up
to 1.8 K day−1 inside the biomass-burning plume, implied vertical
mixing with turbulent kinetic energy of 0.3 m2 s−2.
The effect of secondary ice production parameterization on the
simulation of a cold frontal rainband
Authors: Sullivan Sylvia C. , Barthlott Christian , Crosier Jonathan , Nenes Athanasios , Hoose Corinna
Published: June 2018

Abstract. Secondary ice production via processes like rime splintering, frozen droplet shattering, and breakup upon ice hydrometeor collision have been proposed to explain discrepancies between in-cloud ice crystal and ice-nucleating particle numbers. To understand the impact of this kind of additional ice number generation on surface precipitation, we present one of the first studies to implement frozen droplet shattering and ice-ice collisional breakup parameterizations in a larger-scale model. We simulate a cold frontal rainband from the Aerosol Properties, PRocesses, And InfluenceS on the Earth's Climate campaign and investigate the impact of the new parameterizations on the simulated ice crystal number concentrations (ICNC) and precipitation. Near the convective regions of the rainband, contributions to ICNC can be as large from secondary production as from primary nucleation, but ICNCs greater than 50 L−1 remain underestimated by the model. Addition of the secondary production parameterizations also clearly intensifies the differences in both accumulated precipitation and precipitation rate between the convective towers and non-convective gap regions. We suggest, then, that secondary ice production parameterizations be included in large-scale models on the basis of large hydrometeor concentration and convective activity criteria.
Technical Note: Possible errors in flux measurements due to limited digitalization
Authors: Foken Thomas , Babel Wolfgang , Thomas Christoph
Published: June 2018

Abstract. Recently reported trends of carbon dioxide uptakes pose the question if trends may results of the digitalization of gas analysers and sonic anemometers used in the 1990s. Simulating a 12-bit digitalization and the instrument error reported for the R2 and R3 sonic anemometers elsewhere, the influence of these deficits in comparison to the 16-bit digitalization were quantified. Both issues have an effect only on trace gas fluxes of small magnitude, mainly for the carbon rather than for the water vapour fluxes. The influence on the annual net ecosystem exchange is negligible.
Surficial sediment texture database for the south-western Iberian Atlantic margin
Authors: Costas Susana , Ramires Margarida , de Sousa Luisa B. , Mendes Isabel , Ferreira Oscar
Published: June 2018

Abstract. Assessing the impact of changes on the environment driven by natural or
anthropogenic forcers includes the comparison between antecedent and
post-event conditions. The latter is particularly relevant in order to better
understand to which extent those changes actually impact or alter a
particular environment and associated services and to determine the
resilience of a system. In this regard, it becomes essential to create or
provide databases to inform about baseline conditions. Here, we present a
database that integrates surficial sediment samples collected and analysed
for textural characterization within the framework of a series of research
projects over circa 20 years. Collected samples along the south-western
Atlantic margin of the Iberian Peninsula extend from estuaries and beaches to
the adjacent continental shelf. For the case of the more dynamic
environments, namely coastal sandy barriers, samples were repeated over time
in order to capture the intrinsic variability of the system. Examples of the
utility of this data set for a variety of purposes and environments are also
included within this paper through three examples. Therefore, here we show
the added value of the database as it can be used to assess the impact of a
particular event or activity at an estuary by providing baseline conditions,
evaluate the continental shelf sediment suitability for nourishment
activities, or contribute to the understanding of the morphodynamics and
classification of beaches. Finally, it is worth stating the importance of
such databases to analyse medium- to long-term variability as the one induced
by sea level rise, changes in storminess, or human activities. The
open-access data presented here are at https://doi.org/10.1594/PANGAEA.883104.
A conservative reconstruction scheme for the interpolation of extensive quantities in the Lagrangian particle dispersion model FLEXPART
Authors: Hittmeir Sabine , Philipp Anne , Seibert Petra
Published: June 2018

Abstract. Lagrangian particle dispersion models require interpolation of all
meteorological input variables to the position in space and time of
computational particles. The widely used model FLEXPART uses linear
interpolation for this purpose, implying that the discrete input fields
contain point values. As this is not the case for precipitation (and other
fluxes) which represent cell averages or integrals, a preprocessing scheme is
applied which ensures the conservation of the integral quantity with the
linear interpolation in FLEXPART, at least for the temporal dimension.
However, this mass conservation is not ensured per grid cell, and the scheme
thus has undesirable properties such as temporal smoothing of the
precipitation rates. Therefore, a new reconstruction algorithm was developed,
in two variants. It introduces additional supporting grid points in each time
interval and is to be used with a piecewise linear interpolation to
reconstruct the precipitation time series in FLEXPART. It fulfils the desired
requirements by preserving the integral precipitation in each time interval,
guaranteeing continuity at interval boundaries, and maintaining
non-negativity. The function values of the reconstruction algorithm at the
sub-grid and boundary grid points constitute the degrees of freedom, which
can be prescribed in various ways. With the requirements mentioned it was
possible to derive a suitable piecewise linear reconstruction. To improve the
monotonicity behaviour, two versions of a filter were also developed that
form a part of the final algorithm. Currently, the algorithm is meant
primarily for the temporal dimension. It was shown to significantly improve
the reconstruction of hourly precipitation time series from 3-hourly input
data. Preliminary considerations for the extension to additional dimensions
are also included as well as suggestions for a range of possible applications
beyond the case of precipitation in a Lagrangian particle model.
Acoustic mapping of mixed layer depth
Authors: Stranne Christian , Mayer Larry , Jakobsson Martin , Weidner Elizabeth , Jerram Kevin , Weber Thomas C. , Anderson Leif G. , Nilsson Johan , Björk Göran , Gårdfeldt Katarina
Published: June 2018

Abstract. The ocean surface mixed layer is a nearly universal feature of the world
oceans. Variations in the depth of the mixed layer (MLD) influences the
exchange of heat, fresh water (through evaporation), and gases between the
atmosphere and the ocean and constitutes one of the major factors controlling
ocean primary production as it affects the vertical distribution of
biological and chemical components in near-surface waters. Direct
observations of the MLD are traditionally made by means of conductivity,
temperature, and depth (CTD) casts. However, CTD instrument deployment limits
the observation of temporal and spatial variability in the MLD. Here, we
present an alternative method in which acoustic mapping of the MLD is done
remotely by means of commercially available ship-mounted echo sounders. The
method is shown to be highly accurate when the MLD is well defined and
biological scattering does not dominate the acoustic returns. These
prerequisites are often met in the open ocean and it is shown that the method
is successful in 95 % of data collected in the central Arctic Ocean. The
primary advantages of acoustically mapping the MLD over CTD measurements are
(1) considerably higher temporal and horizontal resolutions and
(2) potentially larger spatial coverage.
Complete Talar Extrusion Treated With an Antibiotic Cement Spacer and Staged Femoral Head Allograft
Authors: Huang Philip , Lundgren Mary Elizabeth , Garapati Rajeev
Published: June 2018

Complete talar extrusion is rare and usually associated with a high-energy mechanism of injury causing complete dissociation of the talus from the surrounding bony and soft-tissue structures with enough force to expel the talus out of the body. Treatment can be complicated by infection, osteonecrosis, posttraumatic osteoarthritis, and leg length discrepancy, which may require multiple subsequent surgeries for improved outcome and quality of life. Reimplantation of the native talus affords maintenance of joint height and favorable outcomes have been reported. Failed reimplantations have been successfully managed with arthrodesis with or without a bone allograft. We report a case of talar extrusion initially treated with a talus-shaped impregnated antibiotic spacer, followed by femoral head allograft and tibiocalcaneal fusion. This treatment resulted in radiographic evidence of bony fusion at 12 weeks without subsequent infection and good clinical outcome at 2-year follow-up.