Extreme ultraviolet and X-ray spectroheliograph for OSO-H

A complex scientific instrument was designed, fabricated, tested, and calibrated for launch onboard OSO-H. This instrument consisted of four spectroheliographs and an X-ray polarimeter. The instrument is designed to study solar radiation at selected wavelengths in the X-ray and the extreme ultraviolet ranges, make observations at the H-alpha wavelength, and measure the degree of polarization of X-ray emissions

Morphological development and cytochrome c oxidase activity in Streptomyces lividans are dependent on the action of a copper bound Sco protein

Copper has an important role in the life cycle of many streptomycetes, stimulating the developmental switch between vegetative mycelium and aerial hyphae concomitant with the production of antibiotics. In streptomycetes, a gene encoding for a putative Sco-like protein has been identified and is part of an operon that contains two other genes predicted to handle cellular copper. We report on the Sco-like protein from Streptomyces lividans (Sco Sl ) and present a series of experiments that firmly establish a role for Sco Sl as a copper metallochaperone as opposed to a role as a thiol-disulphide reductase that has been assigned to other bacterial Sco proteins. Under low copper concentrations, a Δ sco mutant in S. lividans displays two phenotypes; the development switch between vegetative mycelium and aerial hyphae stalls and cytochrome c oxidase (CcO) activity is significantly decreased. At elevated copper levels, the development and CcO activity in the Δ sco mutant are restored to wild-type levels and are thus independent of Sco Sl . A CcO knockout reveals that morphological development is independent of CcO activity leading us to suggest that Sco Sl has at least two targets in S. lividans . We establish that one Sco Sl target is the dinuclear Cu A domain of CcO and it is the cupric form of Sco Sl that is functionally active. The mechanism of cupric ion capture by Sco Sl has been investigated, and an important role for a conserved His residue is identified. </jats:p

Variability in shape of the dental arcade of Homo sapiens in Late Pleistocene and modern samples from southern Africa

Mandibles are among the most common skeletal elements of Late Pleistocene specimens of Homo sapiens from southern African sites (notably Klasies River Mouth and Border Cave). For this reason mandibles have been selected for study to compare with samples drawn from modem populations (including South African negroes, Khoisanoid "Bushmen" and caucasoids). An analysis of shape of the dental arcade, based on the spatial distribution of molars, premolars and canines, indicates that several of the Late Pleistocene samples (including KRM 41815) are outside the range of variation found in modem African and caucasoid populations, and in this respect, cannot be described as "anatomically modem", sensu strictu. There appears to be a trend in the process of modernisation, from very flared dental arcades (notably in the case of the Kabwe skull, representing "archaic" H. sapiens), through moderately flared arcades (as found in Late Pleistocene "nearly modem" samples) towards a less flared condition which is found in modern Africans and caucasoids.Foundation for Research Developmen

Workshop on research p riorities for migrant pests of agriculture in Southern Africa, Plant Protection Research Institute, Pretoria, South Africa, 24–26 March 1999

The Workshop was held at the Agricultural Research Council – Plant Protection Research Institute, Pretoria, from 24 to 26 March 1999 and was attended by 66 delegates from Botswana, Malawi, Namibia, South Africa, Sudan, Swaziland, Tanzania, United Kingdom, Zimbabwe, the International Red Locust Control Organisation for Central and Southern Africa (IRLCO-CSA) and the Food and Agriculture Organization of the United Nations (FAO) (see pages xiii–xvi for list of delegates). The first day focused on presenting a synopsis of current research on the three main migrant pests in southern Africa – armyworm, locusts and quelea – and described the national, regional (IRLCO-CSA, Southern African Development Community, SADC) and international (FAO) infrastructures for dealing with them. On the second and third days, after consideration of the issues to be addressed to ensure uptake of research findings by resource-poor farmers, the Workshop divided into three groups according to pest species. Each group adopted a generalised Logical Framework approach to identifying research priorities, constraints, risks and linkages. Four Logical Frameworks, covering armyworm, locust, quelea and cross-cutting research priorities were developed and an informal ad hoc steering committee (names annotated in list, pages xiii–xvi) undertook to bring together the Workshop’s findings in a Summary Report and to make recommendations on further actions

Die Akkreditierung - eine Leistungsbeurteilung mit System? : die Überprüfung der Qualität der universitären Ausbildung am Beispiel AACSB

Die zunehmende Intensität des interuniversitären Wettbewerbs erhöht die Bedeutung des Qualitätsmanagements. Die Qualität von Forschung und Lehre wird durch Evaluationen er-fasst. Evaluation ist Teil einer Akkreditierung, bei der vor allem geprüft wird, ob die Qualität eines Studiengangs vorgegebenen Mindeststandards entspricht. In der deutschen Hochschul-landschaft gibt es bisher kein etabliertes Modell zur Qualitätsmessung und -verbesserung. Der vorliegende Beitrag stellt ein Instrument zur Messung der Qualität von (wirtschaftswissen-schaftlichen) Fakultäten vor. Das behandelte Modell, das AACSB (The International Asso-ciation for Management Education)-Modell zur Leistungsbeurteilung und Akkreditierung, besticht durch seine erschöpfende Behandlung aller mit der Qualität einer Fakultät verbunde-nen Themenkomplexe. Es geht damit weit über eine bloße Evaluation von Studium und Lehre hinaus. Im Hinblick auf Rigorosität und Handhabbarkeit ist es u.E. den bisher entwickelten Konzepten überlegen. empirischen Studie zu quantifizieren

Coronary artery bypass grafting: Part 1—the evolution over the first 50 years

Surgical treatment for angina pectoris was first proposed in 1899. Decades of experimental surgery for coronary artery disease finally led to the introduction of coronary artery bypass grafting (CABG) in 1964. Now that we are approaching 50 years of CABG experience, it is appropriate to summarize the advancement of CABG into a procedure that is safe and efficient. This review provides a historical recapitulation of experimental surgery, the evolution of the surgical techniques and the utilization of CABG. Furthermore, data on contemporary clinical outcomes are discusse

Exploiting the weekly cycle as observed over Europe to analyse aerosol indirect effects in two climate models: Exploiting the weekly cycle as observed over Europe to analyseaerosol indirect effects in two climate models

A weekly cycle in aerosol pollution and some meteorological quantities is observed over Europe. In the present study we exploit this effect to analyse aerosol-cloudradiation interactions. A weekly cycle is imposed on anthropogenic emissions in two general circulation models that include parameterizations of aerosol processes and cloud microphysics. It is found that the simulated weekly cycles in sulfur dioxide, sulfate, and aerosol optical depth in both models agree reasonably well with those observed indicating model skill in simulating the aerosol cycle. A distinct weekly cycle in cloud droplet number concentration is demonstrated in both observations and models. For other variables, such as cloud liquid water path, cloud cover, top-of-the-atmosphere radiation fluxes, precipitation, and surface temperature, large variability and contradictory results between observations, model simulations, and model control simulations without a weekly cycle in emissions prevent us from reaching any firm conclusions about the potential aerosol impact on meteorology or the realism of the modelled second aerosol indirect effects

Exploiting the weekly cycle as observed over Europe to analyse aerosol indirect effects in two climate models: Exploiting the weekly cycle as observed over Europe to analyseaerosol indirect effects in two climate models

A weekly cycle in aerosol pollution and some meteorological quantities is observed over Europe. In the present study we exploit this effect to analyse aerosol-cloudradiation interactions. A weekly cycle is imposed on anthropogenic emissions in two general circulation models that include parameterizations of aerosol processes and cloud microphysics. It is found that the simulated weekly cycles in sulfur dioxide, sulfate, and aerosol optical depth in both models agree reasonably well with those observed indicating model skill in simulating the aerosol cycle. A distinct weekly cycle in cloud droplet number concentration is demonstrated in both observations and models. For other variables, such as cloud liquid water path, cloud cover, top-of-the-atmosphere radiation fluxes, precipitation, and surface temperature, large variability and contradictory results between observations, model simulations, and model control simulations without a weekly cycle in emissions prevent us from reaching any firm conclusions about the potential aerosol impact on meteorology or the realism of the modelled second aerosol indirect effects