Rapid urbanization, employment crisis and poverty in African LDCs:A new development strategy and aid policy

Rapid urbanization is a fact of live even in the least developed countries (LDCs) where the lion’s share of the population presently lives in rural areas and will continue to do so for decades to come. At the turn of the millennium 75% of the LDCs’ population still lived in rural areas and 71% of the LDCs’ labor force was involved in agriculture. But even though the largest share of their population lives in rural areas and directly or indirectly derives their livelihoods from agriculture, a rapidly increasing share of the population migrates to urban centers in search for employment opportunities outside agriculture in industrial enterprises or the services sector. The main purpose of this paper is to examine the causes and consequences -- in particular, the policy implications -- of the ongoing urbanization in the African LDCs. It is found that the employment opportunities in either rural or the urban sector are not growing adequately. This paper attempts to analyze the emerging trends and patterns of urbanization in the African LDCs within a dynamic dual-dual framework with a strong emphasis on rural-urban migration and the informal sectors. The analysis pinpoints, among other things, the need to build up productive capacities in order to create adequate employment and incomes for the rapidly growing population---particularly in the urban areas. The development of productive capacities, which is a precondition for the creation of productive employment opportunities, is a central element of viable poverty reduction strategy for Bangladesh as well. Without significant poverty reduction it is impossible to think of viable urbanization on the basis of sustainable development criteria in this group of very African countries. The donors, especially the OECD/ DAC countries, should provide the necessary financial backing for such a sustainable and equitable development strategy for Africa. It is necessary to reverse the trends in aid, and to provide a much larger share of aid for productive sector development, including the development of rural and urban areas, and the development of agricultural and non-agricultural sectors in line with the perspective of the dual-dual model. Although urban centers mostly host non-agricultural industries, sustainable urbanization also strongly depends on what happens in the agricultural sectors. Productive employment opportunities in rural areas are important in order to combat an unsustainable migration from rural areas to urban centers, and productive employment opportunities in urban centers are essential to absorb the rapidly increasing labor force in the non-agricultural sector.Urbanization, Africa, LDCs, Dual-Dual Model, Informal Sector, Poverty, Employment, Capabilities

How to Support the Process of Forming Analogies to Facilitate Model-Building in Science Education

In the following article we illustrate the importance of learning with models and analogies in science education. Learning with models is both exciting and promotes greater comprehension capabilities, whilst an understanding of how the analogies model works, remains to be a very interesting topic also. The issueexplains the process of formingmodels and describe how this processcan be supported in the classroom. We describe the processof analogy formation and examine how far the use of specific models, can support the processes of analogy formation. A proficient handling of models plays an important role in this context. Therefore, the focus would be on model competence, learning with and learning about models. In addition, the process of modeling,will be explained and theoretical founded, on a circle of modelling postulated in mathematical didactics. The particular benefit of the following article is the merging of different views on modelling: psychology, pedagogy, natural scientifical and mathematical didactics

The Neuro-Inflammatory-Vascular Circuit: Evidence for a Sex-Dependent Interrelation?

Cardiovascular disease (CVD) is the leading cause of death worldwide with mortality rates in women currently exceeding those in men. To date, evidence is widely lacking for unique female determinants of CVD. However, strong associations with psychological stress, obesity or elevated inflammatory biomarkers with adverse cardiovascular outcomes in women have been identified in various studies. Interestingly, amygdalar metabolic activity, a central neural structure involved in emotional stress processing, has proven to be an independent predictor of major adverse cardiovascular events (MACE). Moreover, upregulated amygdalar metabolism was directly linked to myocardial injury in women, but not in men. This newly suggested sex-dependent brain-heart interrelation was further supported by the discovery that bone marrow activity, a surrogate parameter of inflammation, represents a potential bridging link between amygdalar activity and cardiovascular pathology by fueling inflammatory processes that promote atherosclerotic disease. Such malignant cascade of events might account, at least in part, for the excess female mortality seen in women with coronary artery disease and calls for sex-specific research toward pharmacologic or behavioral modulators to improve cardiovascular outcomes, particularly in women. This mini review summarizes recent advances in cardiovascular sex-specific medicine, thereby focusing on the interplay between the limbic system, autonomic regulation and inflammatory biomarkers, which may help to tailor CVD management toward the female cardiovascular phenotype

Magnesocenophane-Catalyzed Amine Borane Dehydrocoupling

The Lewis acidities of a series of [n]magnesocenophanes (1 a-d) have been investigated computationally and found to be a function of the tilt of the cyclopentadienyl moieties. Their catalytic abilities in amine borane dehydrogenation/dehydrocoupling reactions have been probed, and C[1]magnesocenophane (1 a) has been shown to effectively catalyze the dehydrogenation/dehydrocoupling of dimethylamine borane (2 a) and diisopropylamine borane (2 b) under ambient conditions. Furthermore, the mechanism of the reaction with 2 a has been investigated experimentally and computationally, and the results imply a ligand-assisted mechanism involving stepwise proton and hydride transfer, with dimethylaminoborane as the key intermediate

Monte Carlo Modeling of Terahertz Quantum Cascade Detectors

We demonstrate an Ensemble Monte Carlo (EMC) modeling approach for robust and rigorous simulations of photovoltaic quantum cascade detectors (QCDs) in the mid-infrared (mid-IR) and terahertz (THz) range. The existing EMC simulation tool for quantum cascade lasers (QCLs) was extended to simulate the photovoltaic transport effects in QCDs at thermal equilibrium under zero bias. Here, we present the results of the EMC study of a THz detector design with a detection wavelength of 84 $\mu$m. The simulation results show good agreement with experimental data. For a temperature of 10 K we obtain a peak responsivity of 9.4 mA/W.Comment: 3 pages, 2 figures, has been accepted for 33rd URSI GAS

How to investigate insight: A proposal

Abstract One of the most challenging issues in the Weld of creativity is Wnding an approach conducent to understanding the cognitive and neural mechanisms underlying insight. We propose investigating the process of insight within the context of implicit learning paradigms. The training tasks in implicit learning paradigms are regularly constructed and, although participants are not informed about the existence of such a regularity, some of them gain insight into this regular pattern during training. This process of spontaneously arising explicit knowledge during an incidental learning situation strongly resembles the process of Wnding the solution for an insight problem. The main advantage of these incidental learning situations is the opportunity to investigate the process of insight on a trial-by-trial basis. This would be of particularly interest to researchers who want to relate the process of insight to neural activity. We begin with a description of our main Wndings concerning the emergence of explicit knowledge in implicit learning and continue with detailed descriptions of our implicit learning paradigm and data-analytic strategies

Tibial Strains are Sensitive to Speed, but not Grade, Perturbations During Running

Tibial stress fractures are thought to result from a fatigue-failure process where bone failure is highly dependent on peak strain magnitude. Little is known regarding the mechanical loading environment of the tibia during graded running despite the prevalence of this terrain. To probe the sensitivity of the mechanical loading environment of the tibia to running grade, tibial strains were quantified using a combined musculoskeletal-finite element modeling routine during graded and level running. Seventeen participants ran on a treadmill at $\pm$10{\deg}, $\pm$5{\deg}, and 0{\deg} while force and motion data were captured. At each grade, participants ran at 3.33 m/s and a grade-adjusted speed, that was 2.20 m/s and 4.17 m/s for uphill and downhill conditions, respectively. Muscle and joint contact forces were estimated using inverse-dynamics-based static optimization. These forces were applied to a participant-informed finite element model of the tibia. 50th percentile pressure-modified von Mises strain was lower ($\leq$-130 $\mu\varepsilon$) during downhill running compared to level and uphill running at 3.33 m/s. However, neither 95th percentile strain (peak strain) nor the volume of bone experiencing strains $\geq$4000 $\mu\varepsilon$ (strained volume) were different between grades (F(4)$\leq$3.28, p$\geq$0.01). In contrast, peak strain and strained volume were highly sensitive to running speed (F(1)$\geq$10.61, p$\leq$0.001), where a 1 m/s increase in speed resulting in a 9 % and 155 % increase in peak strain and strained volume, respectively. Overall, these findings suggest that faster running speeds, but not changes in running grade, may increase the risk of developing a tibial stress fracture

Digitale Bildung

Die Autor*innen betrachten zunächst Anforderungen, Begründungen, Herausforderungen und Chancen Digitaler Bildung und ordnen dies in ein Modell von Lehrerprofessionalisierung ein. (DIPF/Orig.

Sialic acid transport and catabolism are cooperatively regulated by SiaR and CRP in nontypeable Haemophilus influenzae

BACKGROUND: The transport and catabolism of sialic acid, a critical virulence factor for nontypeable Haemophilus influenzae, is regulated by two transcription factors, SiaR and CRP. RESULTS: Using a mutagenesis approach, glucosamine-6-phosphate (GlcN-6P) was identified as a co-activator for SiaR. Evidence for the cooperative regulation of both the sialic acid catabolic and transport operons suggested that cooperativity between SiaR and CRP is required for regulation. cAMP was unable to influence the expression of the catabolic operon in the absence of SiaR but was able to induce catabolic operon expression when both SiaR and GlcN-6P were present. Alteration of helical phasing supported this observation by uncoupling SiaR and CRP regulation. The insertion of one half-turn of DNA between the SiaR and CRP operators resulted in the loss of SiaR-mediated repression of the transport operon while eliminating cAMP-dependent induction of the catabolic operon when GlcN-6P was present. SiaR and CRP were found to bind to their respective operators simultaneously and GlcN-6P altered the interaction of SiaR with its operator. CONCLUSIONS: These results suggest multiple novel features for the regulation of these two adjacent operons. SiaR functions as both a repressor and an activator and SiaR and CRP interact to regulate both operons from a single set of operators