Biomechanical Characerization and Evaluation of Conservative Clubfoot Correction

Congential talipes equinovarus, or clubfoot, affects approximately 200,000 newborns worldwide each year and presents with equinovarus of the hindfoot, as well as cavus and adduction of the midfoot. In addition to bone malformation and displacement, soft tissue contractures encapsulate the medial and posterior aspects of the affected foot. The Ponseti method is a conservative treatment that progressively repositions the clubfoot through weekly casting, followed by bracing. Concerns exist regarding the variability in outcomes, resistance to treatment, and risk of relapse, which occur in approximately 10% of the population. Potential factors contributing to variability and resistant clubfoot include cast material performance, as well as biomechanics of medial soft tissue of the clubfoot. There are no clinical guidelines for clubfoot correction based upon mechanical response of commonly used casting materials, nor the mechanics of the medial fibrotic clubfoot tissue. Untreated or under-corrected clubfoot can result in abnormal gait, pain, and further foot deformity. The purpose of this research was to investigate the biomechanics of conservative clubfoot correction through: i) a kinematic assessment of the creep behavior of three common cast materials used during conservative correction, ii) development and validation of a benchtop system for the mechanical evaluation of miniature soft tissue specimens, and iii) performing a mechanical analysis to model the behavior of medial fibrotic mass tissue (MFMT) from children with clubfoot. Utilizing a model to simulate clubfoot correction, creep rotation was found to be dependent on cast material with maximum values for plaster-of-Paris (θ ≈ 2.1 deg). Reducing cast creep may result in a more efficient correction. Utilizing nylon monofilament, the benchtop system was validated against a commercial system (MTS). Versatility was demonstrated with quasistatic and viscoelastic protocols performed on PTFE tape and rabbit ligament, respectively. Clubfoot MFMT underwent a quasistatic and viscoelastic protocol, including requisite preconditioning as well as stress relaxation. Major findings include high specimen variability, less relaxation than reported for normal deltoid ligaments, and estimated QLV model parameters with R2 \u3e 0.8 for 16 specimens. Results from this research provide mechanical insight into the correction process that may lead to individualized, evidence-based clubfoot care. Future directions include in vivo analysis of tissue properties and mechanical-genetic correlation

Vision in the Hyperiid Amphipod Scina crassicornis

Light microscopy and extracellular electrophysiology were used to investigate eye structure and visual physiology of the hyperiid amphipod Scina crassicornis, a mesopelagic species that emits unusually short-wavelength luminescence (λmax=435-444 nm). The overall eye morphology is most similar to some previously described deep-dwelling amphipods, though not other hyperiids. Electroretinograms suggest that S. crassicornis possesses a relatively sensitive eye with slow temporal dynamics, and a monochromatic visual system (λmax=472 nm). Vision in S. crassicornis is well-suited for life in mesopelagic waters, and its short-wavelength luminescence does not play a role in intraspecific sexual signalling

Visual Physiology of the Antarctic Amphipod Abyssorchomene plebs

Although the visual systems of animals living in the cold, dark water of the deep sea have been investigated for some time, little is known about vision in animals inhabiting polar oceans, where temperatures are even colder and irradiance fluctuates dramatically with ice cover and season. Physiology of the compound eye of the amphipod Abyssorchomene plebs (Gammaridea: Lysianassoidea), a common Antarctic benthic scavenger, was studied electrophysiologically by electroretinography. A. plebs has a monochromatic visual system with a spectral sensitivity maximum at 487 nm, and higher sensitivity at ultraviolet wavelengths than predicted by a visual pigment template. While irradiance sensitivity determined from V/log I curves is comparable to that of mesopelagic crustaceans, temporal resolution calculated from response waveform dynamics and as determined by critical flicker fusion frequency suggest that the A. plebs eye is slower than that of crustaceans from the deep sea. A. plebs photoreceptors are physiologically adapted for a slow lifestyle in a low-light environment, where maximizing photon capture occurs at the expense of detecting fast events in the visual scene

The Argentine Banking and Exchange Rate Crisis of 2001: Can We Learn Something New from Financial Crises?

After more than ten years under a Currency Board regime, successful in abating inflation and ensuring macroeconomic and financial stability, in January 2002, the country was forced to abandon the “Convertibilidad” and moved to a floating exchange regime. Is this twin crisis different from those experienced by Argentina in 1995 or earlier in the 1980’s? A remarkable difference from past experiences was the apparent strength of the Argentine Financial System, as a consequence of deliberate and systematic process of reforms that put its regulatory framework close to those of developed countries. However, the crisis revealed two sources of financial fragility ´probably underestimated during the good times. First, the combination of a currency board regime and highly dollarized banks’ balance sheets implied a solvency risk for the financial system in case the economy had to adjust to a shock either trough a nominal devaluation or a deflationary process. The other hidden risk for the financial system was the non regulated exposure of banks to sovereign risk. Using a dynamic panel data model we study the behavior of individual banks’ deposits during the prolonged twin crisis suffered by Argentina since November 2000. Our aim was to determine if this event could have been a “sun spot” phenomenon, i.e. a random event not related to the real economy or the consequence of a change in economic agents perception about the trend of the Argentine economy., i.e. an increase on aggregate risk. Our results strongly favour the second hypothesis. “Macro fundamentals” like devaluation risk, the EMBI spread, the change in international reserves and the change in industrial production, played an important roll in explaining the behavior of deposits during the crisis. On the contrary , banks’ “fundamentals” did not help to explain the dynamics of deposits in this crisis, with the exception of a leverage ratio. We also introduced the interest by individual banks on deposits, to test if depositors took it as an indicator of banks’ strength, flying more intensely from banks that paid higher interest rates to retain deposits. The results for the complete sample period confirm this intuition. The share of government debt holdings in banks’ portfolio was also significant for one of the sub periods of the sample, confirming that banks that were large lenders of the government were subject to a more intense run.Facultad de Ciencias Económica

The Argentine Banking and Exchange Rate Crisis of 2001: Can We Learn Something New from Financial Crises?

After more than ten years under a Currency Board regime, successful in abating inflation and ensuring macroeconomic and financial stability, in January 2002, the country was forced to abandon the “Convertibilidad” and moved to a floating exchange regime. Is this twin crisis different from those experienced by Argentina in 1995 or earlier in the 1980’s? A remarkable difference from past experiences was the apparent strength of the Argentine Financial System, as a consequence of deliberate and systematic process of reforms that put its regulatory framework close to those of developed countries. However, the crisis revealed two sources of financial fragility ´probably underestimated during the good times. First, the combination of a currency board regime and highly dollarized banks’ balance sheets implied a solvency risk for the financial system in case the economy had to adjust to a shock either trough a nominal devaluation or a deflationary process. The other hidden risk for the financial system was the non regulated exposure of banks to sovereign risk. Using a dynamic panel data model we study the behavior of individual banks’ deposits during the prolonged twin crisis suffered by Argentina since November 2000. Our aim was to determine if this event could have been a “sun spot” phenomenon, i.e. a random event not related to the real economy or the consequence of a change in economic agents perception about the trend of the Argentine economy., i.e. an increase on aggregate risk. Our results strongly favour the second hypothesis. “Macro fundamentals” like devaluation risk, the EMBI spread, the change in international reserves and the change in industrial production, played an important roll in explaining the behavior of deposits during the crisis. On the contrary , banks’ “fundamentals” did not help to explain the dynamics of deposits in this crisis, with the exception of a leverage ratio. We also introduced the interest by individual banks on deposits, to test if depositors took it as an indicator of banks’ strength, flying more intensely from banks that paid higher interest rates to retain deposits. The results for the complete sample period confirm this intuition. The share of government debt holdings in banks’ portfolio was also significant for one of the sub periods of the sample, confirming that banks that were large lenders of the government were subject to a more intense run.Facultad de Ciencias Económica

Limiting Organisational Rights of Minority Unions: POPCRU v Ledwaba 2013 11 BLLR 1137 (LC)

The Labour Relations Act 66 of 1995 unequivocally promotes the policy choice of majoritarianism, in furtherance of orderly collective bargaining and the democratisation of the workplace. The majoritarian model aims to minimise the proliferation of trade unions in a single workplace and to encourage the system of a representative trade union. Section 18(1) of the Labour Relations Act enables majority unions to enter into collective agreements setting thresholds of representivity for the granting of access, stop-order and trade-union leave rights to minority unions. In furtherance of the majoritarian framework, collective agreements concluded between majority unions and employers can be extended to non-parties to the agreement in terms of section 23(1)(d) of the Labour Relations Act provided specified requirements are satisfied. In Police & Prisons Civil Rights Union v Ledwaba 2013 11 BLLR 1137 (LC) (POPCRU) the Labour Court was required to consider if the collective agreements concluded between the employer and the majority union could be relied upon to prohibit the minority union from securing organisational rights. In so doing, the Labour Court had to reconcile the fundamental principle of freedom of association and the right to fair labour practices (to organise and engage in unfettered collective bargaining) within the context of the majoritarian framework. The Labour Court in POPCRU held that the collective agreement concluded with the majority union must have preference over the organisational rights of minority unions, in keeping with the principle of collective bargaining hierarchy and the legislative framework.   This case note argues that, while the finding of the labour court in POPCRU is correct on the facts and is in keeping with the principle of majoritarianism, the legislative model may no longer be suitable within the context of the current socio-economic and political landscape. Strike violence, loss of confidence in existing bargaining structures, and the alienation of vulnerable employees from majority unions has resulted in minority unions taking up the cudgels of frustrated and disempowered employees, as witnessed in the Marikana experience. The note suggests that in the light of the changing dynamics of the collective bargaining environment, it may be time to revisit the majoritarian model.   &nbsp

Public Servants' Right to Strike in Lesotho, Botswana and South Africa – A Comparative Study

Restrictions on the rights of public officers to strike are permitted by the Constitutions of Lesotho, Botswana and South Africa, where such limitations are reasonable, necessary and justifiable in a democratic society. The limitation of this right in the context of public servants is endorsed by the ILO in the Freedom of Association Digest of Decisions and Principles which holds that "[t]he right to strike can be restricted or even prohibited in the public service or in essential services in so far as a strike there could cause serious hardship to the national community and provided that these limitations are accompanied by certain compensatory guarantees".[1] Public officers in Lesotho are deprived of the right to join trade unions or to strike, without exception or justification. Furthermore in Lesotho no dispute resolution mechanism exists to effectively facilitate the final resolution of disputes of interest in the public sector. This paper considers whether the limitations imposed on the freedom and right to strike of public officers in Lesotho are in breach of international obligations and are reasonable and justifiable in a free and democratic society committed to the rule of law. In so doing a comparative analysis of the jurisdictions of South Africa and Botswana is undertaken. It concludes that Lesotho is in breach of its obligations as a member state of the ILO and its constitutional commitment to freedom of association and needs to be urgently addressed.  &nbsp

Ciberespaço: novas formas da interação social

Ciberspace establishes new forms of communication which transform and amplify interaction between men. The purpose of our thought was to identify how communication transforms relations of production and exchange and transforms the forms of space. The development of this analysis attempts to identify the current transformations that govern the relations which define the new mode of production and appropriation of spaces. The central nucleus of that formula is in the relation between knowledge and action, when the development of new technologies of communication and information capacitates the nations to produce, accumulate and propagate knowledge, leading to the action of intelligent individuals who conduct social developmentLe ciberespace constitue des nouvelles formes de communication qui transforment et amplifient I'interaction entre les hommes. L 'objectif de notre reflexion est de comprendre comment la communication transforme les relations de production, d' échange et de transformation des formes de I ’espace. Le developpement de I’analyse cherche a identifier les transformmations en cours, qui regissent les relations qui expliquent les nouvelles formes de production et apropriation des espaces. Leprincipal de I ’ analise est dans la relation savoir et action, oil le développement de nouvelles tecnologies de communication et informations donnent la capacité aux nations de produire, d 'accumuler et de propager le savoir, qui conduit à I'action des individus qui ecrivent le développement social.O ciberespaço se constitui em novas formas da comunicação que transformam e ampliam a interação entre os homens. O objetivo de nossa reflexão foi compreender como a comunicação transforma relações de produção e troca e muda as formas do espaço. O desenvolvimento da análise procura identificar as transformações em curso, que regem as relações que definem as novas formas da produção, apropriação e gestão dos espaços. O núcleo central da formulação está na relação conhecimento e ação, quando o desenvolvimento de novas tecnologias de comunicação e informação pode capacitar as nações a produzir, acumular e difundir o conhecimento o que conduz para uma ação de indivíduos inteligentes que escrevem o desenvolvimento social