The Implications of Capital-Skill Complementarity in Economies with Large Informal Sectors

In most developing nations, formal workers tend to be more experienced and educated than informal workers, a fact often interpreted as evidence that low-skill workers face barriers to entry into the formal sector. Yet, there exists little direct evidence that labor markets are segmented in those nations. This paper describes a model where significant differences arise between workers across sectors even though labor markets are perfectly competitive. In equilibrium, the informal sector emphasizes low-skill work because informal managers have access to less outside financing, and choose to substitute low-skill labor for physical capital. We argue that subsidiary implications of the model for the organization of production are borne out by the existing evidence on informal economic activities in developing countries.

Finance matters

We present a model in which the importance of financial intermediation for development can be measured. We generate financial differences by varying the degree to which contracts can be enforced. Economies where enforcement is poor employ less capital and less efficient technologies. Yet, accounting for all the observed dispersion output requires a higher capital share or a lower elasticity of substitution between capital and labor than usually assumed. We find that the effects of changes in those technological parameters on output are markedly larger when financial frictions are present. Finance, that is, matters.Financial markets ; Productivity

Unconventional order-disorder phase transition in improper ferroelectric hexagonal manganites

The improper ferroelectricity in YMnO$_3$ and other related multiferroic hexagonal manganites are known to cause topologically protected ferroelectric domains that give rise to rich and diverse physical phenomena. The local structure and structural coherence across the ferroelectric transition, however, were previously not well understood. Here we reveal the evolution of the local structure with temperature in YMnO$_3$ using neutron total scattering techniques, and interpret them with the help of first-principles calculations. The results show that, at room temperature, the local and average structures are consistent with the established ferroelectric $P6_3cm$ symmetry. On heating, both local and average structural analyses show striking anomalies from $\sim 800$ K up to the Curie temperature consistent with increasing fluctuations of the order parameter angle. These fluctuations result in an unusual local symmetry lowering into a \textit{continuum of structures} on heating. This local symmetry breaking persists into the high-symmetry non-polar phase, constituting an unconventional type of order-disorder transition.Comment: 10 pages, 5 figure

RELATIONSHIPS AMONG COMMUNITIES, IDENTITIES, AND ACADEMIC PERFORMANCE OF AFRICAN AMERICAN ENGINEERING UNDERGRADUATES

A potential barrier to increasing diversity in engineering may be the failure of engineering colleges within predominantly White institutions (PWI's) to understand, acknowledge, and/or accommodate the unique perspectives of its under-represented minority students. Numerous studies have shown us that the success of many under-represented minority students at PWI's may be impacted by lack of community, feelings of isolation from their culture, and disidentification within their field (Foor, Walden, & Trytten, 2007; Seymour & Hewitt, 1997; Shehab et al., 2007; Shehab, Murphy, & Foor, 2011; Walden & Shehab, 2009).This study represents a phenomenological analysis of data collected by the Research Institute for STEM Education (RISE), who conducted a study seeking to identify factors contributing to the success of under-represented and under-served minority engineering students at a predominantly White research institution. Minority undergraduate engineering students participated in face-to-face interviews designed to engage them in reflection and discussion of their experiences as engineering students. The interview data for 19 successful African American undergraduate engineering students were selected from three academic performance groups: excellers, persisters, and strugglers. Their interview data were analyzed to address the question of how community and identity contribute to the academic achievement of successful African American engineering undergraduates of a predominantly White institution.To answer this question, student experiential narratives were interpreted through the lenses of community, Black identity, and engineering identity to better understand how these constructs influence the student academic performances. Results suggest that community, Black identity, engineering identity, and academic performance may moderate each other. Students found community in different places based on their academic grouping. Excellers found community in a wider range of places and were most likely to find community in engineering organizations with majority White membership. Persisters and strugglers were more limited in the places they found community and mostly participated in more ethnocentric organizations. Persisters and Strugglers were more reliant on Black reference groups for community than were excellers, indicating stronger reliance on same race communities. Engineering discursive identity increased as academic performance increased. Surprisingly, several students from each grouping held negative images of engineers which often clashed with their own identities, perhaps suggesting a potential friction between Black and Engineering identities

Plasticity of fetal cartilaginous cells.

Tissue-specific stem cells found in adult tissues can participate in the repair process following injury. However, adult tissues, such as articular cartilage and intervertebral disc, have low regeneration capacity, whereas fetal tissues, such as articular cartilage, show high regeneration ability. The presence of fetal stem cells in fetal cartilaginous tissues and their involvement in the regeneration of fetal cartilage is unknown. The aim of the study was to assess the chondrogenic differentiation and the plasticity of fetal cartilaginous cells. We compared the TGF-β3-induced chondrogenic differentiation of human fetal cells isolated from spine and cartilage tissues to that of human bone marrow stromal cells (BMSC). Stem cell surface markers and adipogenic and osteogenic plasticity of the two fetal cell types were also assessed. TGF-β3 stimulation of fetal cells cultured in high cell density led to the production of aggrecan, type I and II collagens, and variable levels of type X collagen. Although fetal cells showed the same pattern of surface stem cell markers as BMSCs, both type of fetal cells had lower adipogenic and osteogenic differentiation capacity than BMSCs. Fetal cells from femoral head showed higher adipogenic differentiation than fetal cells from spine. These results show that fetal cells are already differentiated cells and may be a good compromise between stem cells and adult tissue cells for a cell-based therapy

Bud development, flowering and fruit set of Moringa oleifera Lam. (Horseradish Tree) as affected by various irrigation levels

Moringa oleifera is becoming increasingly popular as an industrial crop due to its multitude of useful attributes as water purifier, nutritional supplement and biofuel feedstock. Given its tolerance to sub-optimal growing conditions, most of the current and anticipated cultivation areas are in medium to low rainfall areas. This study aimed to assess the effect of various irrigation levels on floral initiation, flowering and fruit set. Three treatments namely, a 900 mm (900IT), 600 mm (600IT) and 300 mm (300IT) per annum irrigation treatment were administered through drip irrigation, simulating three total annual rainfall amounts. Individual inflorescences from each treatment were tagged during floral initiation and monitored throughout until fruit set. Flower bud initiation was highest at the 300IT and lowest at the 900IT for two consecutive growing seasons. Fruit set on the other hand, decreased with the decrease in irrigation treatment. Floral abortion, reduced pollen viability as well as moisture stress in the style were contributing factors to the reduction in fruiting/yield observed at the 300IT. Moderate water stress prior to floral initiation could stimulate flower initiation, however, this should be followed by sufficient irrigation to ensure good pollination, fruit set and yield

Die Ge-Komposita im Mittelhochdeutschen : Eine zur Zeit noch bestehende Möglichkeit, eine Aussage aspektuell zu markieren

Ge- signale l’absence de tout caractère actualisant, de toute actualité dans un temps particulier, signale la discongruence à l’actualisation une et particulière (LSL, 65, note15). On comprend pourquoi le sens absolu de la négation nie "jamais” a tant d’affinité avec le composé. Cette prédication (structure d\u27affirmation en ge-)  fait “l’économie de l’épreuve et de la réduction du singulier” pour entrer de plain-pied dans l’universel (Levinas). Das getue ich niemer mêre : Cette prédication est d’emblée installée non pas “en un moment quelconque du temps”, comme le formule Maurice Marache, mais plutôt dans ce que F. W. J. Schelling appelle l’éternité, ce temps virtuel qui ne cesse de donner du temps sans jamais s’épuiser, dans le temps en réserve d’actualisations. Ge- serait un aspect “anti-détensif, qui bloquerait, empêcherait toute détension du verbe, toute descente vers une incarnation du processus dans le réel. (cf. Daviet-Taylor, HEL, 1993).

The political identities of neighbourhood planning in England

The rise of neighbourhood planning has been characterised as another step in a remorseless de-politicisation of the public sphere. A policy initiated by the Coalition Government in England to create the conditions for local communities to support housing growth, neighbourhood planning appears to evidence a continuing retreat from political debate and contestation. Clear boundaries are established for the holistic integration of participatory democracy into the strategic plan-making of the local authority. These boundaries seek to take politics out of development decisions and exclude all issues of contention from discussion. They achieve this goal at the cost of arming participatory democracy with a collective identity around which new antagonisms may develop. Drawing on the post-political theories of Chantal Mouffe this paper identifies the return of antagonism and conflict to participation in spatial planning. Key to its argument is the concept of the boundary or frontier that in Mouffe’s theoretical framework institutionalises conflict between political entities. Drawing on primary research with neighbourhood development plans in England the paper explores how boundary conditions and boundary designations generate antagonism and necessitate political action. The paper charts the development of the collective identities that result from these boundary lines and argues for the potential for neighbourhood planning to restore political conflict to the politics of housing development