Market Imperfections, Wealth Inequality, and the Distribution of Trade Gains

Globalization increasingly involves less-developed countries (LDCs), i.e., economies which usually suffer from severe imperfections in their financial systems. Taking these imperfections seriously, we analyze how credit frictions affect the distributive impact of trade liberalizations. We find that free trade significantly widens income differences among firm owners in LDCs: While wealthy entrepreneurs are better off, relatively poor business people lose. Intuitively, with integrated markets, profit margins shrink -- which makes access to credit particularly difficult for the least affluent agents. Richer entrepreneurs, by contrast, win because they can take advantage of new export opportunities. Our findings resonate well with a number of empirical regularities, in particular with the observation that some liberalizing LDCs have observed a surge in top-income shares.Wealth inequality; trade liberalization; credit market frictions; top incomes

Equity and Efficiency under Imperfect Credit Markets

Recent macroeconomic research discusses credit market imperfections as a key channel through which inequality retards growth. Limited borrowing prevents the less affluent individuals from investing the efficient amount, and the inefficiencies are considered to become stronger as inequality rises. This paper, though, argues that higher inequality may actually boost aggregate output even with convex technologies and limited borrowing. Less equality in the middle or at the top end of the distribution is associated with a lower borrowing rate and hence better access to credit for the poor. We find, however, that rising relative poverty is unambiguously bad for economic performance. Hence, we suggest that future empirical work on the inequality-growth nexus should use more specific measures of inequality rather than measures of ”overall” inequality such as the Gini index.capital market imperfections, inequality, growth, efficiency

Who Gains from Non-Collusive Corruption?

We explore the impact of non-collusive corruption on the wealth distribution. We show that the distributional consequences depend crucially on the degree of capital market imperfections. With perfect capital markets, corruption does not redistribute wealth within the private sector. However, if borrowing is limited, members of the ''middle class'' suffer most since bribery drives them out of the capital market. This makes access to credit easier for wealthy individuals such that a group of them even wins. Finally, we provide cross-country evidence showing that a high level of corruption and a polarization of the distribution go indeed hand in hand.corruption, income inequality, development

Resistance Development to Bacteriophages Occurring during Bacteriophage Therapy.

Bacteriophage (phage) therapy, i.e., the use of viruses that infect bacteria as antimicrobial agents, is a promising alternative to conventional antibiotics. Indeed, resistance to antibiotics has become a major public health problem after decades of extensive usage. However, one of the main questions regarding phage therapy is the possible rapid emergence of phage-resistant bacterial variants, which could impede favourable treatment outcomes. Experimental data has shown that phage-resistant variants occurred in up to 80% of studies targeting the intestinal milieu and 50% of studies using sepsis models. Phage-resistant variants have also been observed in human studies, as described in three out of four clinical trials that recorded the emergence of phage resistance. On the other hand, recent animal studies suggest that bacterial mutations that confer phage-resistance may result in fitness costs in the resistant bacterium, which, in turn, could benefit the host. Thus, phage resistance should not be underestimated and efforts should be made to develop methodologies for monitoring and preventing it. Moreover, understanding and taking advantage of the resistance-induced fitness costs in bacterial pathogens is a potentially promising avenue

Bacteriophages and other mobile genetic elements in microbial host adaptation, physiopathology and potential therapy

La présente thèse comprend trois chapitres qui étudient la manière dont les éléments génétiques mobiles (EGMs), y compris les bactériophages (phages), peuvent être impliqués dans (i) l’adaptation des bactéries à différents mammifères, (ii) le parasitage des bactéries (par les phages) tout en préservant l’hôte bactérien, et (iii) le détournement des phages à des fins thérapeutiques (phagothérapie) pour traiter les infections bactériennes. Le premier chapitre s’intéresse au récent saut d’espèces de la souche humaine de Staphylococcus aureus du Complexe Clonal 8 (CC8) aux bovins, chez qui elle est responsable de mastites. Nous démontrons que le premier événement responsable de ce saut est l’acquisition d’une cassette chromosomique staphylococcique appelée SCCbov. SCCbov est un EGM codant pour une nouvelle protéine de surface appelée « Adherence-Like Bovine protein » (ADLB) impliquée dans la pathogenèse des mastites. En effet, les souches de CC8 bovines envahissent et tuent les cellules mammaires bovines en culture. Au contraire, l’excision de SCCbov ou l’inactivation d’ADLB diminuent la virulence dans ces conditions. Le second événement du saut est la perte d’un phage inséré dans le chromosome (ou prophage) qui interrompt le gène de la lipase. La restauration de l’activité lipase est susceptible de faciliter la croissance des staphylocoques dans le milieu riche en lipides du lait. Le troisième événement est la perte d’un prophage interrompant le gène de la -hémolysine. La restauration de la -hémolysine promeut la colonisation épithéliale. Enfin, nous avons construit des souches isogéniques de CC8 comportant différentes combinaisons de ces EGMs, permettant d’étudier le saut d’espèce dans une approche « d’évolution inverse ». En conclusion, c’est ce trafic d’EGMs qui est à l’origine du saut des CC8 humains aux bovins. Le second chapitre étudie la relation structure-fonction et la régulation de l’activité de la lysine du phage PlySK1249 de Streptococcus dysgalactiae. Les phages produisent des lysines en fin de réplication pour lyser les bactéries hôtes et libérer leur progéniture. Cependant, libérer les lysines dans l’environnement risque de lyser des bactéries voisines qui portent le même phage, ou des bactéries constituant de nouvelles proies. PlySK1249 a une structure multi- modulaire intrigante, constituée d’un domaine central de liaison à la paroi bactérienne, encadré par un domaine amidase (bactériolytique) et domaine endopeptidase (CHAP; non- bactériolytique). Nous démontrons que cette multi-modularité remplit trois fonctions. (A) la combinaison des deux domaines enzymatiques et du domaine de liaison est hautement synergique en termes de dégradation de la paroi et de lyse bactérienne. (B) le domaine de liaison prévient la diffusion de la lysine en la gardant liée aux débris de paroi cellulaire après la lyse bactérienne. (C) en présence de paroi bactérienne PlySK1249 est progressivement clivée et par une protéase de la paroi bactérienne (encore non-identifiée), qui désamorce son activité bactéricide. En résumé, la structure multi-modulaire de PlySK1249 implique une régulation inter-domaines sophistiquée, permettant de circonscrire la lyse à la cellule infectée afin de ne pas compromettre l’intégrité des cellules avoisinantes. Le troisième chapitre est une preuve de concept de la phagothérapie, utilisant un cocktail de 12 phages anti-Pseudomonas aeruginosa et un modèle d’endocardite expérimentale (EE) chez le rat. Les phages se sont révélés hautement bactéricides in vitro (perte de >6 logs CFU/ml en 6 h), mais sélectionnaient des pseudomonas résistants. Les phages étaient aussi bactéricides in vivo (perte de >2 logs CFU/g de végétations en 6 h), mais ne sélectionnaient pas de résistance chez les animaux. L’absence de résistance in vivo était due au coût d’adaptation chez l’animal, car elle affectait la synthèse des pili et du LPS, deux facteurs de virulence critiques de pseudomonas. Enfin, la combinaison de phages et d’antibiotiques (dans ce cas la ciprofloxacine) s’est révélée hautement synergique, prévenant la résistance in vitro, et démontrant une fréquence de stérilisation des végétations cardiaques (>50% en 6 h) sans précédent dans l‘EE à P. aeruginosa. En conclusion, la phagothérapie combinée ou non aux antibiotiques ouvre des promesses nouvelles pour le traitement des infections bactériennes systémiques sévères. -- The present thesis comes in three chapters studying how mobile genetic elements (MGEs), including bacterial viruses called bacteriophages (phages), may be involved in (i) adaptation of bacteria to different mammalian hosts, (ii) parasiting bacteria (in the case of prophages) while preserving their bacterial hosts, and (iii) new therapeutic applications. The first chapter studied the recent human-to-bovine host jump of typical human Staphylococcus aureus Clonal Complex 8 (CC8) to cowherds, where it causes invasive mastitis. We show that the first event driving the human-to-bovine jump was the acquisition, by human CC8 strains, of a new “staphylococcal cassette chromosome” called SCCbov. SCCbov is a new MGE encoding for a new bacterial surface protein called Adherence-Like Bovine protein (or ADLB), which is implicated in mastitis pathogenesis. Indeed, while parent bovine CC8 readily invaded mammary cells lines, then escaped endosomes, and eventually lysed cultured cells, excision of SCCbov or knocking out ADLB decreased invasiveness and mammary cell death. We then show that the second event of the host-jump was the loss of a phage inserted in the bacterial chromosome (called a prophage), which interrupted the lipase- encoding gene. The loss of this prophage restored S. aureus lipase activity, which is likely to facilitate staphylococcal growth in the lipid-rich milk milieu. The third event was the loss of a β- hemolysin-interrupting prophage, restoring β-hemolysin activity, which was shown to promote epithelial colonization. Finally, we constructed isogenic bovine CC8 strains carrying these MGEs in various combinations, which will help determine the host-jump dynamics in a “reverse evolution” approach. Thus, MGE trafficking was the driving force behind the adaptation of human CC8 staphylococci to cows. The second chapter dissected the molecular structure-function activity and regulation of phage lysin PlySK1249 from Streptococcus dysgalactiae. Phages produce lysins at the end of their replication cycle to lyse host bacteria and release their progeny. However, uncontrolled diffusion of lysins in the surrounding might also lyse neighboring bacteria carrying sibling phages or potential new bacterial hosts. PlySK1249 has an intriguing multimodular structure with a central cell wall-binding domain (CWBD) bracketed by a bacteriolytic amidase domain and a non-bacteriolytic endopeptidase (CHAP) domain. We show that this multi-modularity serves a triple purpose. On the one hand, combining the two enzymatic and the CWBD domains led to a synergistic activity in cell wall degradation and bacterial lysis. On other hand, the CWBD prevented lysin diffusion after bacterial lysis by keeping lysin attached to cell wall debris. Finally, we found that in the presence (but not in the absence) of cell wall protein extract, PlySK1249 was subject to proteolytic cleavage by an as yet unknown bacterial wall protease, further introducing posttranscriptional modification in order to control its lytic activity. Thus, the multimodular structure of PlySK1249 implicates sophisticated inter-domain interactions promoting synergistic – yet cell-restricted – lysis, in order to release the phage progeny without jeopardizing neighboring host cells. The third chapter was a proof of concept study of phage therapy, using a cocktail of 12 phages directed against Pseudomonas aeruginosa and a model of P. aeruginosa experimental endocarditis (EE). Phages were highly bactericidal in vitro (loss of >6 logs CFU/ml in 6 h), but selected for phage resistance. Phages were also bactericidal in vivo (loss of >2 logs CFU/g of vegetations in 6 h), but did not select for resistance in animals. The absence of in vivo resistance selection was due to the fitness cost of resistance, which affected synthesis of bacterial pilus or LPS, two P. aeruginosa virulence factors that are critical for in vivo infection. Finally, combining phages with antibiotics (namely ciprofloxacin) was highly synergistic, prevented resistance selection in vitro, and cured notoriously difficult-to-treat EE due to P. aeruginosa at an unprecedented rate, healing >50% of the animals within 6 h of therapy. Thus, thoughtful utilization of phage therapy combined or not with antibiotics might become an alternative to treat severe systemic bacterial infections

Income shocks and social unrest: theory and evidence

Combining theoretical and empirical work, this paper explores the impact of economic shocks on the incidence of social unrest (i.e., mass demonstrations and violent riots) in autocracies. Our theory predicts negative economic shocks to boost unrest since-in bad times-fighting the regime to reduce the level of resource diversion becomes cheaper. Using a new dataset on political instability in Africa, our empirical analysis confirms this prediction. The instrumental variables estimates-which take into account the potential endogeneity of economic shocks-suggest a significant increase in the level of social unrest as a response to a decline in real per capita GDP.Conflict, social unrest, economic shocks

An exploratory study regarding the impact narcissistic CEOs have on the strategic dynamism of JSE listed companies

Thesis (M.Com. (Accountancy))--University of the Witwatersrand, Faculty of Commerce, Law and Management, School of Accountancy, 2015Many studies considering the effects CEOs‟ characteristics have on the companies they run have been carried out in America. This study considers if organisational outcomes and strategic choices are partially predicted by managerial background characteristics as put forward by Hambrick and Mason (1984). It attempts to determine if the personality traits of CEOs of JSE listed companies (which result in them being classified as a narcissist) have an impact on the financial performance on the company for which they work. As identified by Chatterjee and Hambrick (2007), prior research has explored how executive‟s characteristics are manifested in organisational outcomes, however very little research addresses the narcissistic aspect of CEOs personalities. This study explored whether a relationship exists between CEO narcissism and strategic dynamism in a nonprobability, convenience sample.. A 5-item narcissism index was used as a proxy for narcissism and financial leverage, overhead efficiency and plant and equipment newness, were used to measure strategic dynamism. Multiple regression was used to analyse the data by applying CEO narcissism as the independent variable, strategic dynamism as the dependents variable whilst including control variables, including the CEO tenure, the age of the CEO, the age of the company, and indicator variable for the presence of a COO, the phase of the economy during which the CEO served his tenure and an indicator variable for which industry the company is operating in. The results of this study revealed that there is a viii correlation between the level of narcissism, captured using unobtrusive measures, of a JSE listed company‟s CEO and the level of strategic dynamism of that company. The results of the regression models suggest that whilst there is no observable relationship between narcissism and strategic dynamism, there is a relationship between narcissism and two of the components of strategic dynamism, financial leverage and plant and equipment newness. This research contributes further to the study of the effect of narcissistic CEO‟s on the companies for which they work and suggests that the personality traits of CEOs should be considered by company boards and shareholders when deciding to elect a person as CEO as well as by investors when deciding which companies to invest in

“God werkt geometrisch”–“los holandeses” lo hacen de otra forma: cosmológico-matemática, teosófica y arquitectónicamente

Las tesis de una edad moderna ex-nihilo, creada a sí misma, como prejuicio moderno viene ocultando, a pesar de los estudios minuciosos al respecto, las conexiones más complejas en la formación de la arquitectura moderna que terminan sepultadas bajo las explicaciones más selectivas y tendenciosas. Desde este punto de vista más riguroso, este artículo trata de desentrañar el trasfondo de la aportación holandesa al cuerpo teórico de la arquitectura moderna