Changing Dynamics in the South African Labour Market

Fundamental features of the post-apartheid South African economy include persistent and increasing unemployment alongside extreme levels of household income inequality. These well-established welfare challenges are strongly shaped by the nature of employment and earnings outcomes in the domestic labour market. This chapter reviews some of the major new developments that have occurred in the labour market since 2000. At a macro level the authors document the changing structure of the economy’s sectoral growth trajectory, which has resulted in a relative contraction of the primary and industrial sectors amidst a rapid expansion in the services economy. The latter in turn has delivered an employment path in South Africa, which has been almost exclusively services based. This sectoral shift has occurred alongside a pattern of skills-biased occupational change, and substantial wage growth for those at the top of the earnings distribution. At the same time, the public sector and a corresponding unionized class have expanded and continue to command significant wage premia, while returns to education are declining for specific qualifications. From a policy perspective there have been a series of important labour market interventions aiming to support low-wage workers, with the expansion of minimum wages a notable development in this regard. However, levels of non-compliance with both wage and non-wage labour market regulations are high. We conclude by drawing attention to several active employment policies that have been pursued by the state in an attempt to tackle the unemployment crisis, with mixed results.

Evaluation of plasticity during deformation of carbon steel

The indicator of the degree of relative reduction of the cross-sectional area and the indicator of the degree of development of the necking, more sensitive to changes in the structural parameters and the deformation temperature of carbon steel compared to the traditional were proposed in comparison with the relative contraction and the true deformation index. The role of relaxation of internal stresses and increased mobility of dislocations in the formation of plastic properties of carbon steel is considered.

Contemporary wooden architecture in search of free form

Creation of modern architecture in accordance with the precepts of sustainable development requires an integrated and synergistic design for both new-built and refurbished buildings. The buildings should demonstrate not only the aesthetics, functionality and durability but also have harmless impact on the environment, be effective in material and energy consumption and take into account any risk factors from the point of view of human life and health. Wood, one of the oldest construction materials used by man is present in the built environment from the beginning of the history of architecture. Modernism was characterized by the gradual displacement of wood by other building materials: ceramics, concrete and steel. Physical properties, ease of shaping and effortless process of production, combined with the exceptional ecological potential of wood make wooden structures are widespread again after a period of relative contraction. Creating complex forms in the contemporary architecture and the development of digital design tools coupled with computer technology and CNC woodworking give designers new possibilities for shaping architectural forms. Curvilinear architecture (free form design) rejects Cartesian geometry and conventional language of Euclidean shapes. This article analyzes architectural structures characterized by curvilinear forms and the use of wood as a building material of construction.

Abstract 31: High-density Lipoprotein, a Feed-forward Forechecking Loop

Background: The protective effect of HDL is projected into the cholesterol back-transport of breakdown products of lipid metabolism to the liver. This is a feed-back circuit which controls cholesterol exit. Cholesterol entry could be safeguarded in a feed-forward forechecking loop at the proteoglycan (PG) receptor sites (syndecan, perlecan). HDL is the counter partner in the system of internalization and diffusion control for lipoprotein entry into the vascular wall. Based on stereochemical and chiral conformity with its PG receptor and the much higher negative charge density, HDL owns by far a higher affinity compared with LDL. Methods: Flow-dependent isometric tension, intracellularly recorded membrane potential and cAMP-cGMP were measured in segments of 25 coronaries from heart transplantations. Results and Discussion: Compared to Krebs solution, LDL (100 mg/dL) impaired flow-dilatation and caused a relative contraction by 18.5% (Table). In contrast, HDL (50 mg/dL) and HDL+LDL stimulated flow-dilatation by 31.1% and 41.4%, respectively (p < 0.96). Thus, the contractile effect of LDL was absent in the Krebs-HDL-LDL solution. The same effects were apparent in the membrane potential and cAMP-cGMP-concentrations of the VSM cells. These results are confirmed by ellipsometry measurements, where nanoplaque formation by LDL is suppressed by preincubation with HDL [Siegel, Malmsten, Ermilov: Adv Coll Interface Sci 205 (2014) 275-318]. Conclusion: LDL-cholesterol entry into the vascular wall is effectfully controlled by HDL in a feed-forward forechecking loop (HDL 4х higher affinity constant to the PG receptor). The interaction between both is dominated by competition.

Abstract 166: Interaction Between LDL and Sympathetic Adrenoreceptors

Introduction: LDL is a significant risk factor for cardiovascular disease and is known to impair flow-dependent vasodilatation. Furthermore, it has been demonstrated that LDL can even directly cause vasoconstricton. Recent studies suggested that lower LDL levels, achieved through administration of statins, are correlated with lower blood pressure, independent from pleiotropic statin effects. Our objective was to investigate whether LDL-induced impairment in flow-dilatation was due to an interaction of LDL with sympathetic adrenoreceptors. Materials and Methods: Flow-dependent isometric tension, intracellularly recorded membrane potential and cAMP-cGMP were measured in segments of 22 coronaries from heart transplantations. Results: As compared to Krebs solution, LDL affected flow-dilatation and caused a relative contraction [Δ(T 3 -T 100 ): Krebs 0.459 g; LDL 0.278 g]. Complete blockade of both α- (phentolamine 10 -7 mol/L) and β-receptors (propranolol 10 -7 mol/L) resulted in a ∼50% reduction of flow-dilatation impairment induced by LDL. Blockage of either α- (1) or β-receptors (2) showed smaller effects which added up to the measured effect under blockade of both receptors (4). Similar effects were apparent in the recorded membrane potential of the vascular smooth muscle cells. Discussion: We conclude that the LDL-induced impairment in flow-dependent dilatation is partially due to the interaction between lipoprotein and both α- and β-adrenoreceptors. Since blockade of each receptor resulted in a relative dilatation, we assume that the LDL effect is caused by a stimulation of α-adrenoreceptors and an inhibition of β-adrenoreceptors.

Economic Growth and Structural Change in the United Kingdom, 1870–1914

The paper presents an estimate of the limits to British economic growth in the period 1870–1914. It is argued that in contrast to the historical experience, vigorous and effective exploitation of the technological possibiites of the period would have required the relative expansion of some sectors—most of which, like engineering, were growing in relative size in any case—and the relative contraction of others. The conservatively estimated gains from such counterfactual sectoral shifts of economic activity were found to be of the order of 25 percent to 50 percent of British GNP in 1913. The paper concludes with a brief consideration of why opportunities of this magnitude were not seized.

Glomerular adaptations to chronic dietary salt restriction or excess

Micropuncture studies were performed in 33 Munich-Wistar rats maintained chronically either on dietary NaCl restriction (group 1) or excess (group 2). Values for single nephron (SN) and total kidney glomerular filtration rate (GFR) were identical in both groups. Nevertheless, because of preferential efferent vasoconstriction, glomerular capillary hydraulic pressure (PGC) was higher in group 1, offsetting the lower initial glomerular plasma flow rate (QA) also found in group 1. The pressor response to infusion of exogenous angiotensin II (AII) was less in group 1 than in group 2, suggesting that vascular receptors for AII may have been occupied by endogenous hormone, the latter leading to the efferent arteriolar vasoconstriction. In addition to AII, prostaglandins also appear to be involved in the adaptations of the glomerular microcirculation to chronic variations in salt intake. In group 1, indomethacin or meclofenamate infusion mimicked exogenous AII, causing declines in QA and SNGFR. These changes were lacking in group 2. Because of relative contraction of plasma volume, the vasodilatory effects of prostaglandins appear to be needed in low salt animals to sustain SNGFR and QA. In the high salt group, however, since plasma volume is not contracted, maintenance of SNGFR and QA appears to be less critically dependent on endogenous prostaglandins.