Labetalol infusion for refractory hypertension causing severe hypotension and bradycardia: an issue of patient safety

Incremental doses of intravenous labetalol are safe and effective and, at times, such therapy may need to be augmented by a continuous infusion of labetalol to control severe hypertension. Continuous infusions of labetalol may exceed the recommended maximum daily dose of 300 mg on occasion. We report a case in which hypertension occurring after an abdominal aortic aneurysm repair, initially responsive to intermittent intravenous beta-blockade, became resistant to this therapy leading to the choice of an intravenous labetalol infusion as the therapeutic option. The labetalol infusion resulted in a profound cardiovascular compromise in this postoperative critically ill patient. While infusions of labetalol have successfully been used, prolonged administration in the intensive care unit requires vigilance and the establishment of a therapeutic rationale/policy for interventions, such as the ready availability of glucagon, β-agonists, phosphodiesterase inhibitors, insulin, and vasopressin when severe cardiovascular depression occurs

Investigation of Corrosion Behaviour of Aluminium Alloy Subjected to Laser Shock Peening without a Protective Coating

The effect of shock waves and strain hardening of laser shock peening without protective coating (LSPwC) on alloy AA 6082- T651 was investigated. Analysis of residual stresses confirmed high compression in the near surface layer due to the ultrahigh plastic strains and strain rates induced bymultiple laser shock waves. Corrosion tests in a chloride environment were carried out to determine resistance to localised attack, which was also verified on SEM/EDS. OCP transients confirmed an improved condition, that is, amore positive and stable potential after LSPwCtreatment.Moreover, polarisation resistance of the LSPwCtreated specimen was by a factor of 25 higher compared to the untreated specimen. Analysis of voltammograms confirmed an improved enhanced region of passivity and significantly smaller anodic current density of the LSPwC specimen compared to the untreated one.Through SEM, reduction of pitting attack at the LSPwC specimen surface was confirmed, despite its increased roughness

Experimental ionization of atomic hydrogen with few-cycle pulses

We present the first experimental data on strong-field ionization of atomic hydrogen by few-cycle laser pulses. We obtain quantitative agreement at the 10% level between the data and an {\it ab initio} simulation over a wide range of laser intensities and electron energies

Framework for transforming best practices for landrace conservation to policies

Traditional farming systems and conservation of local cultivars and associated indigenous knowledge are under threat and growing pressure resulting in genetic erosion of crop diversity. These systems are an essential component of sustainable crop production, household income and human nutrition for many of the poor farmers found in fragile semiarid ecosystems of Sub-Saharan Africa (SSA). With the signing of the Convention on Biological Diversity (CBD) in 1992, in situ conservation for crops and their related genetic resources has been given prominent mention in global and national policies for biodiversity conservation. In situ strategies are an important and complementary component of the overall agrobiodiversity conservation efforts that aim to conserve not only crop genetic resources but also crop evolutionary processes. However, policy support of the science and practice of in situ conservation, lag behind CBD commitment in much of SSA. The need for activities on in situ conservation of plant genetic resources is emphasized in the CBD and in Agenda 21. Article 2 of the Convention specifically includes reference to domesticated or cultivated species. This is also anticipated in Article 8, which requires signatory nations to “preserve and maintain knowledge, innovations and practices of indigenous and local communities embodying traditional lifestyles relevant for the conservation and sustainable use of biological diversity …” Agenda 21 reflects this commitment to in situ conservation as an essential component of sustainable agriculture, and in Chapter 14, notes the need for establishing programmes and policies to strengthen in situ conservation. In its second meeting, the Conference of the Parties to the CBD (COP 2) identified implementation of Article 8 of the CBD as a high priority and reaffirmed the importance of regional and international cooperationfor the implementation of this Article. It also stressed the importance of the exchange of relevant information and experience among all stakeholders on measures taken for its implementation (Decision II/7 of COP 2). Many national PGR programmes in SSA are unable to meet their obligations towards in situ (more specifically on-farm) conservation as stated in the CBD and the GPA because of ineffective enabling of national policy environments that do not support traditional farming systems and in situ conservation on-farm. The countries involved in the project were Benin, Burkina Faso, Ghana, Kenya, Malawi, Mali, Uganda and Zimbabwe. Through case studies, the project analysed farming systems in semi-arid ecosystems in these countries, focussing on how these systems supported the conservation of landraces of local and global significance. The methodology described in the present publication was designed within this project to draw out ‘best’ practices on how landraces have been incorporated into farming systems and/or national agricultural policies and biodiversity conservation strategies. On one hand, the farmer or resource user determines what makes the practice the ‘best one’, and they base their choices on a survival strategy or utilitarian point of view. On the other hand, the scientists on the project primarily judged how effective the practices are in conserving agrobiodiversity at different levels. The project attempted to reconcile the two views in developing frameworks for the determination of ‘best practice’

Diffuse versus square-well confining potentials in modelling AA@C60_{60} atoms

Attention: this version-$2$ of the manuscript differs from its previously uploaded version-$1$ (arXiv:1112.6158v1) and subsequently published in 2012 J. Phys. B \textbf{45} 105102 only by a removed typo in Eq.(2) of version-$1$; there was the erroneous factor "2" in both terms in the right-hand-side of the Eq.(2) of version-$1$. Now that the typo is removed, Eq.(2) is correct. A perceived advantage for the replacement of a discontinuous square-well pseudo-potential, which is often used by various researchers as an approximation to the actual C$_{60}$ cage potential in calculations of endohedral atoms $A$@C$_{60}$, by a more realistic diffuse potential is explored. The photoionization of endohedral H@C$_{60}$ and Xe@C$_{60}$ is chosen as the case study. The diffuse potential is modelled by a combination of two Woods-Saxon potentials. It is demonstrated that photoionization spectra of $A$@C$_{60}$ atoms are largely insensitive to the degree $\eta$ of diffuseness of the potential borders, in a reasonably broad range of $\eta$'s. Alternatively, these spectra are found to be insensitive to discontinuity of the square-well potential either. Both potentials result in practically identical calculated spectra. New numerical values for the set of square-well parameters, which lead to a better agreement between experimental and theoretical data for $A$@C$_{60}$ spectra, are recommended for future studies.Comment: 11 pages, 4 figure

Analysis of markets for African leafy vegetables within Nairobi ant its environs and implications for on-farm conservation of biodiversity

African Leafy Vegetables (ALVs) are important sources of essential macro and micro-nutrients. In addition they offer a source of livelihood when marketed, and also contribute to crop biodiversity. Despite these positive aspects, only a few ALVs are grown, marketed and consumed in Kenya. This study analyses the ALV market in Nairobi and the neighbouring areas, highlighting the factors that enable or inhibit its development. Furthermore, the study determined different factors influencing inter- and intra-specific on-farm biodiversity, with a focus on the role of ALV market development