Backbone services as growth enabling factor: An input-output analysis for South Africa

While previous studies highlight the importance of the manufacturing sector in the economy, we argue that rather backbone services play a key role for economic growth. We perform an Input-Output analysis to determine the linkages between backbone services and manufacturing in South Africa. We find high and evenly spread forward linkages of backbone services to the rest of the economy which indicate strong growth-inducing downstream effects. Moreover, the interconnectedness between backbone services and manufacturing is twofold and depends on the level of technology intensity of industries. Especially the production of high technology goods requires a relatively higher share of inputs from backbone services. Thus, an efficient provision of backbone services is essential to induce manufacturing production and enable economic growth in South Africa

Effect of Narrowband UV-B Irradiation on the Growth Performance of House Crickets

Indoor co-cultivation systems can answer to the need for sustainable and resilient food production systems. Rearing organisms under light-emitting diodes (LEDs) irradiation provides the possibility to control and shape the emitted light spectra. UV-B-irradiation (280–315 nm) can positively affect the nutritional composition of different plants and other organisms, whereas information on edible insects is scarce. To evaluate the potential effect of the photosynthetically active radiation (PAR) and LED-emitting LEDs on the rearing and nutritional quality of edible insects, house crickets (Acheta domesticus) were reared from the age of 21 days under controlled LED spectra, with an additional UV-B (0.08 W/m2) dose of 1.15 KJm2 d−1 (illuminated over a period for 4 h per day) for 34 days. UV-B exposure showed no harm to the weight of the crickets and significantly increased their survival by ca. 10% under narrowband UV-B treatment. The nutritional composition including proteins, fat and chitin contents of the insects was not affected by the UV-B light and reached values of 60.03 ± 10.41, 22.38 ± 2.12 and 9.33 ± 1.21%, respectively, under the LED irradiation. Therefore, house crickets can grow under LED irradiation with a positive effect of narrowband UV-B application on their survival

Non-destructive, Contactless and Real-Time Capable Determination of the α’-Martensite Content in Modified Subsurfaces of AISI 304

Cryogenic turning can be used to produce deformation-induced martensite in metastable austenitic steels. Martensite exhibits a higher hardness than austenite and increases the wear resistance of the workpiece. In order to reliably induce a desired martensite content in the subsurface zone during the turning process, a non-destructive, contactless and real-time testing method is necessary. Eddy current testing is an electromagnetic method that is non-destructive, non-contact and real-time capable. Furthermore, eddy current testing has been integrated into production processes many times. Eddy current testing can be used to detect the transformation of paramagnetic austenite to ferromagnetic α′-martensite based on the change in magnetic and electrical properties. Thus, the newly formed subsurface can be characterized and the manufacturing process can be monitored. The objective of this study was to understand the correlation of eddy current testing signals with newly formed α′-martensite in the subsurface of AISI 304 and to quantify the amount formed. The measurements were performed within a machining center. Several methods for reference measurement of martensite content are known in the literature. However, depending on the method used, large discrepancies may occur between the determined contents. Therefore, different analytical methods were used for reference measurements to determine the total martensite content in the subsurface. Metallographic sections, magnetic etching, Mössbauer spectroscopy, and X-ray diffraction with two different analytical methods were employed. Based on the correlation between the eddy current testing signals and the α′-martensite content in the subsurface, process control of the manufacturing process can be achieved in the future

Non-destructive Evaluation of Workpiece Properties along the Hybrid Bearing Bushing Process Chain

To combine the advantages of two materials, hybrid bulk metal workpieces are attractive for subsequent processes such as metal forming. However, hybrid materials rely on the initial bond strength for the effective transfer of applied loads. Thus, a non-destructive evaluation of the bonding along the production process chain is of high interest. To evaluate to what extent non-destructive testing can be employed to monitor the bonding quality between the joining partners steel and aluminum and to characterize the age hardening condition of the aluminum component, ultrasonic testing and electrical conductivity measurements were applied. It was found that a lateral angular co-extrusion process can create homogeneous bonding although the electrical conductivity of the aluminum is altered during processing. A previous bonding before the subsequent die forging process leads to a sufficient bonding in areas with little deformation and is therefore, advantageous compared to unjoined semi-finished products, which do not form a bonding if the deformation ratio is too small. An influence of the subsequent heat treatment on the bonding is not visible in the ultrasonic testing signals though a homogenized electrical conductivity can be detected, which indicates uniform artificial aging conditions of the aluminum allo

Prevalence of chronic urticaria in children and adults across the globe: Systematic review with meta‐analysis

Background and objectives: Urticaria is a frequent skin condition, but reliable prevalence estimates from population studies particularly of the chronic form are scarce. The objective of this study was to systematically evaluate and summarize the prevalence of chronic urticaria by evaluating population-based studies worldwide. Methods: We performed a systematic search in PUBMED and EMBASE for population-based studies of cross-sectional or cohort design and studies based on health insurance/system databases. Risk of bias was assessed using a specific tool for prevalence studies. For meta-analysis, we used a random effects model. Results: Eighteen studies were included in the systematic evaluation and 11 in the meta-analysis including data from over 86 000 000 participants. Risk of bias was mainly moderate, whereas the statistical heterogeneity (I-2) between the studies was high. Asian studies combined showed a higher point prevalence of chronic urticaria (1.4%, 95%-CI 0.5-2.9) than those from Europe (0.5%, 0.2-1.0) and Northern American (0.1%, 0.1-0.1). Women were slightly more affected than men, whereas in children < 15 years we did not find a sex-specific difference in the prevalence. The four studies that examined time trends indicated an increasing prevalence of chronic urticaria over time. Conclusions: On a global level, the prevalence of chronic urticaria showed considerable regional differences. There is a need to obtain more sex-specific population-based and standardized international data particularly for children and adolescents, different chronic urticaria subtypes and potential risk and protective factors

Ein Marshallplan mit Afrika: Geeignetes Konzept für eine nachhaltige Entwicklung?

Im Januar 2017 stellte Bundesminister Dr. Gerd Müller die Eckpunkte für den Marshallplan mit Afrika vor. Statt weiter Geld nach dem Gießkannenprinzip zu verteilen, soll zukünftig der Aufbau stabiler Wirtschaftsstrukturen gezielt gefördert und die Eigenverantwortung der Regierungen gestärkt werden. In seinem Beitrag stellt Bundesminister Gerd Müller den Marshallplan mit Afrika vor und unterstreicht, dass »eine Partnerschaft auf Augenhöhe« sowie eine verstärkte Mobilisierung privaten Kapitals und privater Investitionen erforderlich sei. Für Andreas Freytag und Susanne Fricke, Universität Jena, unterscheidet sich der aktuelle Marshallplan »wohltuend von althergebrachten Entwicklungsstrategien«. So betone er u.a. die Bedeutung der Wirtschaft für den Entwicklungsprozess Afrikas und mahne Investitionen, Bildung für die Jugend, die Einbindung in die Wertschöpfungsketten sowie die Schaffung eines Mittelstandes an. Ihm fehle aber eine definierte Schwerpunktsetzung. Franz Josef Radermacher, Universität Ulm und Club of Rome, beschreibt als Zielsetzung des Marshallplans eine »Wohlstandsexplosion in Afrika, insbesondere in Nordafrika«, die mit allen Nachhaltigkeitsanforderungen kompatibel gestaltet werden soll. Nach Meinung von Axel Dreher und Sarah Langlotz, Universität Heidelberg, sieht der Marshallplan mit Afrika eine Konzentration der Hilfe auf wenige reformwillige Länder vor, wodurch ärmere Länder an Unterstützung verlieren. Zudem betone der Plan Bedingungen, die an die deutschen Zahlungen geknüpft werden sollen. Detaillierte Bedingungen, von deren Einhaltung konkrete Hilfszahlungen abhängig gemacht werden, seien aber wenig sinnvoll. Deutschland solle sich stattdessen in Richtung einer bedingungslosen Budgethilfe bewegen. Werner Abelshauser, Universität Bielefeld, sieht den Marshallplan als Modell absolut ungeeignet, um Entwicklungsländer voranzubringen. Denn anders als in den meisten Empfängerländern Westeuropas nach dem Krieg fehle es dort gerade an Potenzial und wirtsch

Composite materials for innovative urban farming of alternative food sources (macroalgae and crickets)

Facing an inexorable growth of the human population along with substantial environmental changes, the assurance of food security is a major challenge of the present century. To ensure responsible food consumption and production (SDG 12), new approaches in the food system are required. Thus, environmentally controlled, sustainable production of alternative food sources are of key interest for both urban agriculture and food research. To face the current challenge of integrating food production systems within existing structures, multidisciplinary discourses are required. Here, we bring together novel technologies and indoor farming techniques with the aim of supporting the development of sustainable food production systems. For this purpose, we investigated the feasibility of 10 composite materials for their innovative use as structural support in macroalgal cultivation (settlement substrates) and cricket rearing (housing). Considering material resistance, rigidity, and direct material-organism interactions, the bio-based composite polylactic acid (PLA) was identified as a suitable material for joint farming. For macroalgae cultivation, PLA sustained the corrosive cultivation conditions and provided a suitable substrate without affecting the macroalgal physiology or nutritional composition (carotenoids and chlorophylls). For cricket rearing, PLA provided a suitable and recyclable shelter, which was quickly accepted by the animals without any observed harm. In contrast, other common composite components like phenolic resin or aramid were found to be unsuitable due to being harmful for the cultivated organisms or instable toward the applied sterilization procedure. This multidisciplinary study not only provides profound insights in the developing field of urban indoor food production from a new perspective, but also bridges material science and farming approaches to develop new sustainable and resilient food production systems

Enhancement of Intracellular Calcium Ion Mobilization by Moderately but Not Highly Positive Material Surface Charges

Electrostatic forces at the cell interface affect the nature of cell adhesion and function; but there is still limited knowledge about the impact of positive or negative surface charges on cell-material interactions in regenerative medicine. Titanium surfaces with a variety of zeta potentials between −90 mV and +50 mV were generated by functionalizing them with amino polymers, extracellular matrix proteins/peptide motifs and polyelectrolyte multilayers. A significant enhancement of intracellular calcium mobilization was achieved on surfaces with a moderately positive (+1 to +10 mV) compared with a negative zeta potential (−90 to −3 mV). Dramatic losses of cell activity (membrane integrity, viability, proliferation, calcium mobilization) were observed on surfaces with a highly positive zeta potential (+50 mV). This systematic study indicates that cells do not prefer positive charges in general, merely moderately positive ones. The cell behavior of MG-63s could be correlated with the materials’ zeta potential; but not with water contact angle or surface free energy. Our findings present new insights and provide an essential knowledge for future applications in dental and orthopedic surgery. © Copyright © 2020 Gruening, Neuber, Nestler, Lehnfeld, Dubs, Fricke, Schnabelrauch, Helm, Müller, Staehlke and Nebe

which marker is best for prediction? Pooled analysis of four German population-based cohort studies and comparison with a nationwide cohort study

Objective To compare the association between different anthropometric measurements and incident type 2 diabetes mellitus (T2DM) and to assess their predictive ability in different regions of Germany. Methods Data of 10 258 participants from 4 prospective population-based cohorts were pooled to assess the association of body weight, body mass index (BMI), waist circumference (WC), waist-to-hip-ratio (WHR) and waist-to-height-ratio (WHtR) with incident T2DM by calculating HRs of the crude, adjusted and standardised markers, as well as providing receiver operator characteristic (ROC) curves. Differences between HRs and ROCs for the different anthropometric markers were calculated to compare their predictive ability. In addition, data of 3105 participants from the nationwide survey were analysed separately using the same methods to provide a nationally representative comparison. Results Strong associations were found for each anthropometric marker and incidence of T2DM. Among the standardised anthropometric measures, we found the strongest effect on incident T2DM for WC and WHtR in the pooled sample (HR for 1 SD difference in WC 1.97, 95% CI 1.75 to 2.22, HR for WHtR 1.93, 95% CI 1.71 to 2.17 in women) and in female DEGS participants (HR for WC 2.24, 95% CI 1.91 to 2.63, HR for WHtR 2.10, 95% CI 1.81 to 2.44), whereas the strongest association in men was found for WHR among DEGS participants (HR 2.29, 95% CI 1.89 to 2.78). ROC analysis showed WHtR to be the strongest predictor for incident T2DM. Differences in HR and ROCs between the different markers confirmed WC and WHtR to be the best predictors of incident T2DM. Findings were consistent across study regions and age groups (<65 vs ≥65 years). Conclusions We found stronger associations between anthropometric markers that reflect abdominal obesity (ie, WC and WHtR) and incident T2DM than for BMI and weight. The use of these measurements in risk prediction should be encouraged