bluuebunny/crossref_metadata_2025 huggingface dataset:
Embryonic brooding and clonal propagation in tropical eastern Pacific cupuladriid bryozoans
Authors: O'Dea Aaron , Ostrovsky Andrew N. , Rodríguez Felix
Published: August 2009

Colonial invertebrates often mix sexual and asexual methods of propagation, and a comprehensive understanding of both is required for life history study. The asexual cloning of new colonies in cupuladriid bryozoans is much better studied than the formation of new colonies by sexual reproduction. As such, the relative investments of sexual and asexual modes of propagation remain uncertain. This preliminary study explores patterns of embryonic brooding as a measure of investment into sexual reproduction. We conduct a survey of quantity and arrangement of embryos in tropical eastern Pacific cupuladriid colonies and compare this to the frequency of cloning. Species populations show considerable variation in embryonic brooding. Patterns of brooding, both across and within species strongly support the hypothesis that as cloning increases, investment into sexual reproduction decreases. We find preliminary evidence that individual cupuladriid colonies that propagate sexually may senesce like solitary organisms, while species that regularly clone only appear to experience senescence at the level of the zooid.
Bathypolypus sponsalis (Cephalopoda: Octopoda) from the central western Mediterranean Sea
Authors: Cuccu D. , Mereu M. , Follesa M.C. , Deiana A.M. , Cau A.
Published: August 2009

A sample of 360 Bathypolypus sponsalis from the central western Mediterranean Sea (the Sardinian Channel and the Tyrrhenian Sea) was analysed in order to describe size, depth distribution and reproductive data. The first record of the species in the Tyrrhenian Sea and of a spent female are reported in this paper. The size-structure of the sample was in between values of documented data from the western and eastern Mediterranean basins and the minimum mature sizes in both sexes and spermatophore length were similar to previous data from the eastern Mediterranean Sea. Low values of gonadosomatic index and fecundity, the asynchronous ovulation, in addition to an extended reproductive period, have been associated with an intermittent spawning strategy.
Effect of different salinities on survival and growth of prawn,Palaemon elegans(Palaemonidae)
Authors: Yazdani Maryam , Taheri Mehrshad , Seyfabadi Jafar
Published: August 2009

The LS5096 hof prawn,Palaemon elegans, was determined at various salinities (0–45 ppt) with the Caspian Sea salt proportion. In addition, growth indices, survival and moulting at salinities 8, 13 and 18 ppt were also studied during four weeks. All the experiments were carried out in the laboratory (24±1°C). The results showed that more than 50% of the prawns survived at 1 to 30 ppt salinity range, while above and below this range, less than 50% survived within 24 hours. No significant differences (*P > 0.05) in growth parameters such as carapace length (CL) increase, specific growth rate (SGR) and also in survival and moulting rates were observed in prawns reared in salinities 8, 13 and 18 ppt. Mean intermoult period in each salinity was 8.12 ± 3.07, 8.61 ± 2.96 and 8.92 ± 3.47 days, respectively. Salinity 8–18 ppt was found to be the optimum range forP. elegansin the studied length range (CL, 6–9 mm).
Feeding ecology of conger eels (Conger conger) in north-east Atlantic waters
Authors: Xavier José C. , Cherel Yves , Assis Carlos A. , Sendão João , Borges Teresa C.
Published: August 2009

In order to understand how marine ecosystems function, it is essential to study the trophic interactions among the community members, particularly from poorly known regions. In this study, the feeding ecology and diet of conger eels,Conger conger, an abundant fish species with commercial interest, was examined in the north-east Atlantic, off Algarve (southern Portugal) between May 2005 and August 2006. The diet was characterized by species composition, size and mass of prey. Conger eels are opportunistic feeders, cannibalistic, feeding on benthopelagic/pelagic prey (67% by mass and 71% by number) but also benthic prey (32% by mass and 29% by number). Fish (67.8±4.7% in mass) are the main prey of conger eels, followed by cephalopods (16.5±3.8%) and crustaceans (15.6±3.7%). The most numerous (identifiable) fish consumed wereCapros aper, occurring in 90% of the stomach samples that contained food and representing 1.4% in mass, andScomber japonicus, the most important fish in mass (21.1%), which occurred in 4.2% of the stomach samples that contained food. The present study shows that octopodids can play a more important role in the diet of conger eels than previously thought. Of the species preyed upon by conger eels, six species (21% of the total prey taxa) are caught commercially(Trachurus trachurus, Scomber japonicus, Micromesistius poutassou, Helicolenus dactylopterusandConger conger)by local fisheries. As discards by local trawl and longline fisheries do not correspond with the diet ofC. conger, it is likely that most prey ofC. congerin rocky areas were caught actively in that study region.
Leishmania majorH-line attenuated under pressure of gentamicin, induces a Th1 response which protects susceptible BALB/c mice against infection with virulentL. major
Authors: DANESHVAR HAMID , BURCHMORE RICHARD , HAGAN PAUL , PHILLIPS R. STEPHEN
Published: August 2009

An attenuated line ofLeishmania major(L. majorH-line) has been established by culturing promastigotesin vitrounder gentamicin pressure. A modification of the previously described method for the generation of attenuatedL. majoris described, giving rise to attenuated parasites after 8 rather than 12 subpassages. No lesions developed in BALB/c mice infected withL. majorH-line, whereasL. majorwild-type (WT) induced a Th2 like response with progressive lesions. Analysis of splenocyte IFN-γ and IL-4 production following stimulation with promastigotes shows that theL. majorH-line preferentially induces Th1-like responses and possibly down-regulates Th2 responses in BALB/c mice.L. majorH-line parasites remained localized in the skin and draining lymph node, whereasL. majorWT parasites disseminated into the visceral organs of BALB/c mice. Mice infected withL. majorH-line acquired some resistance againstL. majorWT. These results show that the attenuated cell line ofL. majoris not only avirulent but that it may also modulate the host immune response.
Schistosoma mansonicercariae experience influx of macromolecules during skin penetration
Authors: THORNHILL J. , COELHO P. M. Z. , McVEIGH P. , MAULE A. , JURBERG A. D. , KUSEL J. R.
Published: August 2009

We have observed that when cercariae penetrate the skin of mice, there is influx into their tissues of Lucifer Yellow and certain labelled molecules of up to 20 kDa molecular weight. This observation was made using a variety of fluorescent membrane-impermeant compounds injected into the skin before the application of cercariae. This unexpected phenomenon was investigated further by transforming cercariaein vitroin the presence of the membrane-impermeant compounds and examining the distribution by microscopy. In schistosomula derived from this procedure, the nephridiopore and surface membrane were labelled while the pre- and post-acetabular glands were not labelled. The region associated with the oesophagus within the pharyngeal muscle clearly contained the fluorescent molecules, as did the region adjacent to the excretory tubules and the germinal mass. We used cercariae stained with carmine to aid identification of regions labelled with Lucifer Yellow. Although the mechanism of this influx is unclear, the observation is significant. From it, we can suggest an hypothesis that, during skin penetration, exposure of internal tissues of the parasite to external macromolecules represents a novel host-parasite interface.
Parasite communities of a fish assemblage from the intertidal rocky zone of central Chile: similarity and host specificity between temporal and resident fish
Authors: MUÑOZ G. , CORTÉS Y.
Published: August 2009

The different species of a fish assemblage can, to some extent, be similar in terms of their parasite communities, which can be associated with certain ecological host traits. This study compared the parasite community descriptors between temporal and resident fish species composing an intertidal assemblage from central Chile. Host specificity and similarity indices of parasite communities among the fish species were also considered. A total of 1097 fish representing 14 species were collected during spring and summer of 2 consecutive years. A total spectrum of 40 parasite species was found, of which copepods and trematodes were the commonest. Congeneric fish species had the highest similarities in their parasite communities. Based on a cluster analysis, using only some fish species, no group was distinguished using abundance or prevalence of parasites, because 50% of parasite species had high host specificity and only few of them were shared among fish species. Adult parasites showed high host specificity and were found mainly in resident intertidal fish, whereas the temporal fish had parasites with different degrees of specificity. Consequently, resident intertidal fish were characterized by their own parasite species, meaning that their transmissions might be restricted to the intertidal zone.
Translation numbers for a class of maps on the dynamical systems arising from quasicrystals in the real line
Authors: ALISTE-PRIETO JOSÉ
Published: August 2009

In this paper, we study translation sets for non-decreasing maps of the real line with a pattern-equivariant displacement with respect to a quasicrystal. First, we establish a correspondence between these maps and self maps of the continuous hull associated with the quasicrystal that are homotopic to the identity and preserve orientation. Then, by using first-return times and induced maps, we provide a partial description for the translation set of the latter maps in the case where they have fixed points and obtain the existence of a unique translation number in the case where they do not have fixed points. Finally, we investigate the existence of a semiconjugacy from a fixed-point-free map homotopic to the identity on the hull to the translation given by its translation number. We concentrate on semiconjugacies that are also homotopic to the identity and, under a boundedness condition, we prove a generalization of Poincaré’s theorem, finding a sufficient condition for such a semiconjugacy to exist depending on the translation number of the given map.
Quasi-periodic motions in strongly dissipative forced systems
Authors: GENTILE GUIDO
Published: August 2009

We consider a class of ordinary differential equations describing one-dimensional systems with a quasi-periodic forcing term and in the presence of large damping. We discuss the conditions to be assumed on the mechanical force and the forcing term for the existence of quasi-periodic solutions which have the same frequency vector as the forcing.
Staphylococcus aureusis the most common identified cause of cellulitis: a systematic review
Authors: CHIRA S. , MILLER L. G.
Published: August 2009

We utilized Medline to perform a systematic review of the literature to quantify the aetiology of cellulitis with intact skin. Of 808 patients with cellulitis, 127–129 (15·7–16·0%) patients had positive needle aspiration and/or punch biopsy cultures from intact skin. Of the patients with positive cultures, 65 (50·4–51·2%) had cultures positive forStaphylococcus aureus, 35 (27·1–27·6%) for group A streptococcus, and 35–37 (27·1–29·1%) for other pathogens. The most common aetiology of cellulitis with intact skin, when it can be determined, isS. aureus, outnumbering group A streptococcus by a ratio of nearly 2:1. Given the increasing incidence of community-associated methicillin-resistantS. aureusinfections, our findings may have critical therapeutic implications.
Zircon U-Pb dating of Mesozoic volcanic and tectonic events in north-west Palmer Land and south-west Graham Land, Antarctica
Authors: Leat P.T. , Flowerdew M.J. , Riley T.R. , Whitehouse M.J. , Scarrow J.H. , Millar I.L.
Published: August 2009

New whole rock Rb-Sr and zircon U-Pb geochronological data and Sm-Nd isotopic data are presented from the central magmatic arc domain of the Antarctic Peninsula in the area of north-west Palmer Land and south-west Graham Land, Rb-Sr isochrons indicate an age of 169 ± 6 Ma for basement orthogneisses and 132 ± 9 to 71 ± 9 Ma for plutons. A U-Pb age of 183 ± 2.1 Ma, with no detectable inheritance, on zircons from an orthogneiss from Cape Berteaux provides the first reliable age for the orthogneisses, which are interpreted as metamorphosed silicic volcanic rocks, and Sm-Nd data indicate derivation in a mature volcanic arc. The age indicates they may be correlatives of the Jurassic ‘Chon Aike’ volcanism of the eastern Antarctic Peninsula. A U-Pb zircon age of 107 ± 1.7 Ma on a terrestrial volcanic sequence overlying an uncomformity strongly suggests a mid-Cretaceous age for the extensive volcanic cover of north-west Palmer Land that was previously thought to be Jurassic. The unconformity is interpreted to have been a result of compressional uplift related to the Palmer Land event. This is the first date for the event in the western part of the central magmatic arc terrane of the Antarctic Peninsula.
Hydrothermal time germination models for radiata pine (Pinus radiataD. Don)
Authors: Bloomberg M. , Sedcole J.R. , Mason E.G. , Buchan G.
Published: August 2009

The objective of this study was to fit a hydrothermal germination model to germination data for a seedlot of radiata pine (Pinus radiataD. Don). Seeds were incubated for 50 d at constant temperatures and water potentials (T = 12.5–32.5°C, Ψ = 0 to − 1.2 MPa). Most seeds completed germination within 50 d, but for low Ψ and/or non-optimal temperatures (T < 17.5°C,T>25°C) many seeds did not complete germination. In general, germination data conformed to the hydrothermal model. Departures from the model were encountered for slow-germinating seeds at suboptimal temperatures (T ≤ 20°C). To account for these departures, two alternative hydrothermal models were fitted with an additional term for an upwards shift in seed base water potential with increasing time to germination. The alternative models more correctly predicted germination time than the original model. Similarly, reduced percentage germination at supra-optimal temperatures (T>20°C) was explained by including a term in the hydrothermal model which shifted the base water potential of seeds upwards towards zero, which in turn reduced the predicted rate that hydrothermal time would be accumulated by seeds. The rate of this upwards shift in base water potential was dependent on time to complete germination and ambient water potential as well as supra-optimal temperature.
Soybean seed coat cup unloading on plants with low-raffinose, low-stachyose seeds
Authors: Kosina Suzanne M. , Castillo Alexander , Schnebly Steven R. , Obendorf Ralph L.
Published: August 2009

Sucrose, raffinose and stachyose accumulate in soybean [Glycine maxL. (Merrill)] embryos during seed maturation. To determine the relationship of plant maternal composition on seed composition, soluble carbohydrates in three 1-cm2leaf punches at three plant growth stages (R2, R3, R6) and in seed coat cup exudatesin plantawere analysed at four 30-min intervals on soybean plants (R5) with low-raffinose, low-stachyose (LRS) seeds expressing the mutantstc1phenotype; low-raffinose, low-stachyose and low-phytin (LRSP1, LRSP2) seeds expressing the mutantmipsphenotype; or normal raffinose, stachyose and phytin (CHECK) seeds expressing theStc1andMipsphenotype. Leaf sucrose (23.6 μg cm− 2),myo-inositol (9.3 μg cm− 2),d-chiro-inositol (6.7 μg cm− 2),d-ononitol (0.76 μg cm− 2),d-pinitol (50.1 μg cm− 2) and total soluble carbohydrates (107.1 μg cm− 2) were not significantly different between phenotypes.d-chiro-Inositol,myo-inositol,d-pinitol and sucrose were unloaded from soybean seed coat cupsin plantaat decreasing rates over the four sequential periods of sampling. Unloading rates of sucrose andmyo-inositol were highest for LRS,d-pinitol was highest for LRSP2, andd-chiro-inositol was not different between LRS, LRSP1, LRSP2 and CHECK. Free cyclitols were 60% of total soluble carbohydrates in leaves and 20% in seed coat cup exudates. Except for sucrose andd-pinitol, seed phenotype had little influence on the composition of compounds unloaded from seed coats to maturing embryos of low-raffinose, low-stachyose seeds. Maternally supplied cyclitols may contribute, in part, to changes in the composition of cyclitol galactosides stored in mature seeds.
DNA preservation and utility of a historic seed collection
Authors: Leino Matti W. , Hagenblad Jenny , Edqvist Johan , Strese Else-Marie Karlsson
Published: August 2009

Historic collections of biological material are important genetic resources for taxonomic, evolutionary and historical research. In this paper we describe a seed collection dating from 1862 to 1918 maintained at the Swedish Museum of Cultural History. The collection contains over 3000 well-documented seed samples of various agricultural crops, mostly cereals. A subset of 100 samples divided over ten species frequently represented in the collection and a range of ages were tested for germinability and DNA preservation. None of these accessions were found to contain viable seeds. DNA extracted from the seeds was degraded, but the amount of degradation varied between species. DNA quality was evaluated by yield, fragment size and size of amplification product. Quality was highest for DNA extracted fromPisum sativumandVicia sativa. DNA extracted fromBrassica napus,Beta vulgarisandTrifolium pratensewas more fragmented, and DNA extracted fromTriticum aestivum,Secale sereale,Hordeum vulgare,Avena sativaandPhleum pratensewas most degraded. Polymerase chain reaction (PCR) amplification of ribosomal DNA fragments of up to 700 bp was permitted for most samples in all species. To test whether single-copy nuclear genes could be amplified from the extracted DNA, microsatellite markers were used on thePisum sativumandHordeum vulgaresamples. Polymorphisms of microsatellite markers were detected between samples for both species. The results show that the 19th-century seed collection can be utilized to infer genetic relationships among obsolete cultivars as well as for other types of genetic research based on sequence or marker analysis.
Seed germination ecology of the endemic Iberian winter annualsIberis pectinataandZiziphora aragonensis
Authors: Copete Miguel Á. , Herranz José M. , Ferrandis Pablo
Published: August 2009

The germination ecology of the winter annual Iberian endemicsIberis pectinataandZiziphora aragonensiswas investigated in order to better understand adaptations of rare species to their natural habitat and to improveex-situpropagation techniques and management of their habitat. Specifically, we analysed the following aspects: (1) influence of temperature, light conditions and seed age on germination patterns; (2) phenology of germination; (3) germinative response of buried seeds to seasonal temperature changes; and (4) temperature requirements for induction and breaking of secondary dormancy. Germination was substantially lower in darkness than with a photoperiod in both taxa, with this difference being more pronounced inZ. aragonensis. Freshly matured seeds showed conditional physiological dormancy, germinating at low and medium temperatures but not at high temperatures (28/14 and 32/18°C). Germination capability increased with time of dry storage in both species, suggesting the existence of non-deep physiological dormancy. Under greenhouse conditions, germination of both taxa was mostly concentrated in autumn (October–November), while spring percentages were less than 1% of total accumulated germination recorded during the study.I. pectinataandZ. aragonensisseeds buried and exposed to natural seasonal temperature variations in an unheated greenhouse came out of conditional dormancy in summer and re-entered it in winter, thus exhibiting an annual conditional dormancy/non-dormancy cycle. Dormant seeds of both species which were stratified at 28/14 or 32/18°C during an 8-week period, were non-dormant when they were subsequently incubated over a range of temperatures from 5 to 25/10°C. Non-dormant seeds were induced into dormancy when stratified at 5 or 15/4°C for 8 weeks, showing a particularly low germination response at high temperatures. Recommendations for wild-population reinforcement programmes and for the management of the natural habitat of both endemics are discussed.
Definition grundlegender ethischer Fachbegriffe
Authors: Arn Christof
Published: August 2009

Die Ethik nutzt präzise Fachbegriffe zur Analyse von Dilemmasituationen. In diesem Beitrag werden anhand eines konkreten Fallbeispiels Grundbegriffe der Ethik eingeführt. Dabei lässt sich auch zeigen, in welcher Art und Weise diese Fachbegriffe die Problemwahrnehmung schärfen, den Lösungshorizont erweitern und die Kommunikation klären können. Der Beitrag endet mit einem Ausblick auf Möglichkeiten, sich mit ethischer Methodik vertiefter vertraut zu machen.
Der Reanimationsentscheid
Authors: Gerber Andreas U.
Published: August 2009

Herr H., ein 78-jähriger, altersentsprechend gesunder, privat versicherter ehemaliger Kaufmann, wird an einem Samstagabend wegen erstmaliger Angina pectoris notfallmäßig hospitalisiert. Die ärztliche Empfehlung einer stabilisierenden Therapie auf der Intensivpflegestation lehnt er ab. Am nächsten Morgen liegt Herr H. nach erfolgreicher Reanimation intubiert und maschinell beatmet auf der Intenivpflegestation. Sein neurologischer Zustand und seine Prognose sind kritisch. In der Cafeteria gehen die Emotionen hoch: Hat jemand falsch entschieden und gehandelt? Oder doch nicht? Sind die kürzlich unter dem Titel „Reanimationsentscheidungen“ publizierten medizinisch-ethischen Richtlinien der Schweizerischen Akademie der Medizinischen Wissenschaften in und für solche Situationen eine brauchbare Hilfe? Der vorliegende Artikel hat zum Ziel, die Komplexität des Reanimationsentscheides bewusst zu machen. Das diskutierte Beispiel steht dabei stellvertretend für zahlreiche andere medizinisch-ethische Entscheidungssituationen. Der Artikel wirft grundsätzliche Fragen der medizinischen Ethik auf, und gibt einen ersten Einblick in die strukturierte ethische Entscheidungsfindung. Der jungen Ärztin und dem jungen Arzt kann er gut als Start in die faszinierende Welt der medizinischen Ethik dienen und steht deshalb am Anfang dieses Heftes.
Ethische Richtlinien – eine Hilfe im ärztlichen Alltag?
Authors: Pfister Eliane
Published: August 2009

Ethische Richtlinien in der Medizin sind entstanden, um die Interessen von Teilnehmern wissenschaftlicher Studien und von Patienten und Patientinnen in der medizinischen Praxis zu schützen. In der Schweiz sind neben bedeutenden internationalen Richtlinien insbesondere die medizinisch-ethischen Richtlinien der Schweizerischen Akademie der Medizinischen Wissenschaften relevant. In ethisch schwierigen Situationen und für umstrittene Entscheide bedeuten die Richtlinien eine große Hilfe im ärztlichen Alltag. Sie haben das primäre Ziel, in rechtlich ungenügend geregelten Bereichen der Medizin Orientierung zu bieten und ethisch schwierige Entscheidungen zu erleichtern. Die meisten ethischen Richtlinien der SAMW sind für FMH-Mitglieder standesrechtlich verbindlich.
Die Patientenverfügung als Kommunikations- und Entscheidungsinstrument
Authors: Ritzenthaler-Spielmann Daniela
Published: August 2009

Die heutigen Möglichkeiten in der Intensivmedizin und die vielen Therapieoptionen auch bei multimorbiden Patienten führen zu immer öfter notwendigen medizinisch-ethischen Entscheidungen am Lebensende. Wenn der Patient nicht mehr urteilsfähig ist, sind Patientenverfügungen hilfreiche Instrumente, welche diese existentiellen Entscheidungen erleichtern. Kann der Patient aufgrund einer Urteilsunfähigkeit nicht in eine Therapie einwilligen, gilt sein mutmaßlicher Wille als Ausgangspunkt für die stellvertretende Entscheidung. Eine im Voraus schriftlich erstellte Patientenverfügung hilft den mutmaßlichen Willen des Patienten herauszufinden. Patientenverfügungen sollen aber schon vor der Entscheidsituation als Gesprächsinstrument zwischen dem Patienten und seinen Bezugspersonen, aber auch zwischen dem Patient und den behandelnden Ärzten dienen. Ziel der Verfügung ist es, dass der Patient sein Selbstbestimmungsrecht wahrnehmen kann, dass möglichst transparente ethische Entscheidungen in seinem Sinn getroffen werden, aber auch dass seine Bezugspersonen und die medizinischen Behandlungsteams entlastet werden.
Die ärztliche Einweisung – eine Zwangsmaßnahme in der Medizin
Authors: Meier-Allmendinger Diana
Published: August 2009

Zwangsmaßnahmen in der Medizin sind massive Eingriffe in die garantierten Freiheitsrechte einer Person. Sie stehen im Widerspruch zur Selbstbestimmung der betreffenden Person und bedürfen deshalb einer gesetzlichen und ethischen Legitimation. Die ärztliche Einweisung vollzieht sich in einem Spannungsfeld zwischen therapeutischem Auftrag und dem gesellschaftlichen Interesse nach öffentlicher Sicherheit. Für Betroffene bedeutet sie eine schwere Kränkung mit Verletzung ihrer Autonomie. Die ethischen Fragen sind demnach: Ist es gerechtfertigt, die Selbstbestimmung einer Person durch eine Zwangseinweisung als Form von Fürsorgehandeln vorübergehend aufzuheben? In welchem Verhältnis steht die Zwangseinweisung zu den medizinethischen Prinzipien Autonomie, Gutes tun, Nicht schaden und Gerechtigkeit? Es stehen dazu keine Antworten oder Checklisten zur Verfügung. Die Begründung kann letztlich nur in einer Gewichtung der Prinzipien im Einzelfall erfolgen und in Abwägung der Prinzipien untereinander.
Palliative Care – schwierige Entscheidungen am Lebensende
Authors: Kunz Roland
Published: August 2009

Palliative Care strebt die Erhaltung der Lebensqualität von Menschen mit unheilbaren, fortschreitenden Krankheiten an. Ihr Schwerpunkt liegt in der Zeit, in der Sterben und Tod absehbar werden. Neben einer möglichst guten Symptomlinderung kommt der sorgfältigen Entscheidungsfindung unter Respektierung der Autonomie und Würde des Patienten eine zentrale Bedeutung zu. Entscheidungen werden möglichst vorausblickend mit dem Patienten diskutiert und orientieren sich an seinen Wünschen und Prioritäten. Häufige Fragen betreffen den Abbruch laufender Therapien oder den Verzicht auf mögliche Behandlungen, die Behandlung von Schmerzen oder Atemnot unter Inkaufnahme einer möglichen Verkürzung der Überlebenszeit oder eine palliative Sedation. Als hilfreich im Entscheidungsprozess erweist sich das Modell der Balance of Burden and Benefit.
Ethische Probleme der Transplantationsmedizin
Authors: Bosshard Georg
Published: August 2009

Die Transplantationschirurgie ist heute aus der modernen Spitzenmedizin nicht mehr wegzudenken. Sie hat große Therapieerfolge vorzuweisen. Die Möglichkeiten der Transplantationsmedizin werfen aber auch eine Reihe schwerwiegender ethischer Probleme auf. Nach wie vor wird der Großteil der verpflanzten Organe von sogenannten „hirntoten“ Spendern gewonnen. Hier wird die Frage diskutiert, wie weit es berechtigt ist, die irreversibel erloschene Hirnfunktion (Hirntod) mit dem Tod eines individuellen Menschen gleichzusetzen. Ein weiteres Problem betrifft die Verteilung der von hirntoten Menschen gespendeten Organe. Angesichts der zunehmenden Diskrepanz zwischen Organangebot und -nachfrage stellt sich hier unter anderem die Frage, wieweit es gerechtfertigt ist, das Kriterium der Dringlichkeit vor das Kriterium des Nutzens zu stellen. Schließlich konfrontiert uns die zunehmende Praxis der Lebendspende (Leber, Niere) mit der Frage, was „Freiwilligkeit“ in einer solchen Ausnahmesituation bedeutet, und wie diese adäquat abgeklärt werden kann. Erhebliche Probleme wirft in diesem Zusammenhang auch der sogenannte „Transplantationstourismus“ respektive das „organ trafficking“ auf, dessen Häufigkeit heute weltweit auf 5–10% aller Nierentransplantationen geschätzt wird.
Sand oder Öl? – Ethik im Getriebe des Gesundheitswesens. Eine Reflexion über die Rolle der Ethik im Gesundheitswesen und ihr Verhältnis zur Ökonomie
Authors: Baumann-Hölzle Ruth , Streuli Jürg C.
Published: August 2009

Das Eidgenössische Departement des Inneren (EDI) der Schweiz hat im Auftrag von Bundesrat Pascal Couchepin die Auflage gemacht, Ethik und Gesundheitsökonomie gemeinsam in der ärztlichen Weiterbildung als obligatorische Themen einzuführen. Dies, obgleich Ethik und Gesundheitsökonomie oft als sich widersprechende Fachgebiete wahrgenommen werden. Der Artikel zeigt, dass diese Widersprüchlichkeit nur dann besteht, wenn Ethik und Ökonomie gegensätzlichen Grundwerten verpflichtet sind. In einem Gesundheitswesen, das den leidenden Menschen in den Mittelpunkt stellt und die stets begrenzten Leistungen und Mittel fair verteilt, schließen sich Ethik und Ökonomie nicht aus, sondern ergänzen und unterstützen sich gegenseitig. Auf dieser Wertebasis hat Ethik die Aufgabe, bewusste ethische Entscheidungsfindung in Organisationen des Gesundheitswesens strukturell und damit nachhaltig wirksam zu machen und so die Entscheidungsqualität zu fördern, während Ökonomie für einen effizienten Umgang mit den vorhandenen Leistungen und Mitteln sorgt.
Die moderne Medizin als Dienstleistungsunternehmen? Eine ethische Kritik der Marktorientierung in der Medizin
Authors: Maio Giovanni
Published: August 2009

Die moderne Medizin ist gegenwärtig einem beträchtlichen Transformationsprozess unterworfen. Die Sorge um den Kranken wird zunehmend als Dienstleistung verstanden und der Patient in weiten Bereichen der modernen Medizin zum Kunden umdefiniert. Diese Veränderungen sind nicht nur Produkt äußerer Vorgaben, sondern zugleich auch Ausdruck eines bestimmten Selbstverständnisses des modernen Menschen. Gleichzeitig wirken sich diese Veränderungen auf die Identitätsbildung der heilenden Berufe aus, so dass sich die moderne Medizin nicht nur äußerlich, sondern vor allem von innen her verändert. In einer solchen Umbruchszeit erscheint es umso notwendiger, sich mit der Frage zu beschäftigen, was Medizin als Medizin ausmacht und wie die Grundidentität der Medizin als Heil-Kunst auch in Zeiten bewahrt werden kann, in denen mehr von Dienstleistung als von ärztlicher Hilfe die Rede ist.
Psychosoziale Interventionen für Paare, die mit einer Krebserkrankung leben. Eine Literaturübersicht
Authors: Busch Ada-Katrin , Schnepp Wilfried , Spirig Rebecca
Published: August 2009

Eine Krebserkrankung wird von den betroffenen Paaren als Dyade erlebt. Schritt für Schritt müssen diese lernen, die Krankheit in ihr Leben zu integrieren. Es wird vermutet, dass eine psychosoziale Pflegeintervention hier eine wirksame Unterstützung darstellen könnte, wobei unklar ist, welche Maßnahmen die Paare in ihrem Krankheitsmanagement effektiv unterstützen können. Im Rahmen einer Literaturarbeit wurde deshalb den folgenden Forschungsfragen nachgegangen: 1) Welche Interventionen werden Paaren, bei denen eine Partnerin/ein Partner an Krebs erkrankt ist, im Rahmen von Unterstützungsprogrammen zur Verarbeitung der Erkrankung angeboten? 2) Welche Instrumente werden zur Überprüfung der Wirksamkeit dieser Interventionen verwendet und welche Ergebnisse resultieren aus den Evaluationen? 3) Inwieweit tragen solche Interventionen zu einer besseren Krankheitsverarbeitung der Paare bei? In fünf Studien, welche den Ein- und Ausschlusskriterien der Literaturarbeit entsprechen, wurden Interventionsprogramme evaluiert, welche sich im Aufbau und Inhalt stark von einander unterscheiden. Eine große Heterogenität zeigte sich auch bei den eingesetzten Untersuchungsinstrumenten. Dennoch lässt sich zusammenfassend sagen, dass sich die untersuchten psychosozialen Interventionen bei beiden Partnern positiv auf die Paarbeziehung auswirken und Gefühle von Depression und Hoffnungslosigkeit reduziert werden. Zudem fiel es den Partnern leichter, sich in Alltagssituationen beratend zur Seite zu stehen. Aus den Ergebnissen wird der Schluss gezogen, dass Informationsmaterialien und Informationsveranstaltungen in Kombination mit Beratungssequenzen effiziente psychosoziale Pflegeinterventionen für Paare, die mit einer Krebserkrankung leben, darstellen können.
Hautpflege und Hautschutz beim unreifen Frühgeborenen. Eine systematische Literaturübersicht
Authors: Körner Astrid , Dinten-Schmid Barbara , Stoffel Lilian , Hirter Kathrin , Käppeli Silvia
Published: August 2009

Aufgrund der Unreife von Organsystemen und Organfunktionen bestehen bei der Haut des Frühgeborenen physiologische und anatomische Besonderheiten. Die unterentwickelte Haut des sehr kleinen Frühgeborenen sowie die Notwendigkeit der Intensivpflegeüberwachung und der Intensivpflegemaßnahmen erhöhen das Verletzungsrisiko und den Verlust der Hautintegrität. Der unreifen Haut muss in den ersten zwei bis drei Lebenswochen eine hohe Beachtung geschenkt werden – insbesondere bei Kindern, die vor der 28. Schwangerschaftswoche (SSW) geboren wurden. Ritualisierte Handlungen müssen hinterfragt werden. Die vorliegende systematische Literaturübersicht geht der Frage nach der Effektivität pflegerischer Interventionen zur Hautschutzbehandlung des Frühgeborenen unterhalb der 32. Gestationswoche nach. Eine Literatursuche erfolgte in verschiedenen Datenbanken zu folgenden Themen: Assessment der Hautbeschaffenheit, Auswahl und Anwendung von Pflasterprodukten,  Hautpflege mit Emulsion und Körperreinigung (Waschintervall). Obwohl die analysierten Studien einige methodologische Mängel aufweisen, lassen sich folgende Ergebnisse formulieren: Aufgrund des veränderten kindlichen Verhaltens und der gleichbleibenden Keimbesiedlung der Haut soll das Waschintervall auf vier Tage erhöht werden. Als Emulsionstherapie wird in den ersten 2 bis 4 Lebenswochen die Anwendung von Sonnenblumenöl empfohlen. Es wirkt desinfizierend und ist ein relatives kostengünstiges Produkt. Allfällige präventive und therapeutische Hautschutzverbände werden unter Berücksichtigung des Gestationsalters befürwortet. Die Einschätzung der Hautbeschaffenheit mittels eines validen Assessment-Instrumentes und prophylaktischen Maßnahmen sind unerlässlich. Schlussfolgerung: Fundiertes Wissen, Verständnis bezüglich der Prinzipien der Hautpflege bei den Frühgeborenen und eine einheitliche Vorgehensweise in der Hautpflege während der neonatalen Intensivpflege können die Risiken und die Kosten der Behandlung dieser speziellen Population senken. Die Implementierung einer standardisierten, forschungsgestützten Hautpflegerichtlinie kann das Bewusstsein des Neonatologie-Pflegefachpersonals bezüglich der Hautpflegebedürfnisse dieser vulnerablen Patientengruppe erhöhen.
Burnout-Symptome bei österreichischen PflegeschülerInnen im dritten Ausbildungsjahr
Authors: Hausmann Clemens
Published: August 2009

Das Burnout-Syndrom gilt als schwere Belastungsfolge in helfenden Berufen, insbesondere in der Pflege. In der vorliegenden Untersuchung wurden 179 PflegeschülerInnen im dritten Ausbildungsjahr sowie 47 Diplompflegepersonen im Bundesland Salzburg mittels Maslach Burnout Inventory und Satisfaction With Life Scale befragt. Die Burnout-Belastung der PflegeschülerInnen entspricht regional sowie national jener von Diplompflegepersonen und vergleichbaren Beschäftigten in Sozial- und Pflegeberufen. Die spezifischen Stressoren der Pflegeausbildung führen zu etwa gleich großen Belastungsfolgen wie langjährige Berufserfahrung und Belastungsexposition von berufstätigen Pflegepersonen. Die relativ hohe Lebensqualität der PflegeschülerInnen weist auf besondere Ressourcen und Kompensationsmöglichkeiten hin, die noch weiter untersucht werden sollten. Stadt-Land-Unterschiede (geringere Burnout-Werte und höhere Lebenszufriedenheit im ländlichen Raum) sind bei PflegeschülerInnen besonders deutlich ausgeprägt. Im internationalen Vergleich ist die Burnout-Belastung der untersuchten PflegeschülerInnen und Diplompflegepersonen relativ gering. Von allen zum Vergleich herangezogenen Gruppen weisen die Diplompflegepersonen im ländlichen Raum die geringste emotionale Erschöpfung und die PflegeschülerInnen im ländlichen Raum die geringste Depersonalisierung überhaupt auf.
Velocity observations of the California Current derived from satellite imagery
Authors: Matthews D. K. , Emery W. J.
Published: August 2009

This research examines the potential of ocean velocity observations generated from the maximum cross‐correlation technique (MCC) applied to thermal infrared imagery to capture the total current at a high sampling rate, especially in the nearshore region, allowing for a novel view of the California Current. Comparison of 12 years of weekly ocean velocity fields derived from the MCC method with velocity observations from drifting buoys reveals strong correspondence between the data sets. The MCC method, however, is able to produce over ∼10 times the number of observations. Comparison of MCC velocities with geostrophic velocities from altimetry demonstrates differences that suggest ageostrophic currents in the MCC observations that are likely wind driven. The time‐averaged mean velocity field from MCC observations reveals strong offshore jet‐like features that extend off of coastline promontories. Eddy statistics from the MCC velocity observations indicate dramatically different dynamics in the nearshore and offshore regions. Differences in spatial statistics derived from the MCC observations compared to previous studies of the region are attributed to wind‐driven currents in the observations that can dominate the variability of the current in the nearshore region.
Impact of solar radiation on bacterioplankton in Laguna Vilama, a hypersaline Andean lake (4650 m)
Authors: Farías María Eugenia , Fernández‐Zenoff Verónica , Flores Regina , Ordóñez Omar , Estévez Cristina
Published: August 2009

Laguna Vilama is a hypersaline Lake located at 4660 m altitude in the northwest of Argentina high up in the Andean Puna. The impact of ultraviolet (UV) radiation on bacterioplankton was studied by collecting samples at different times of the day. Molecular analysis (DGGE) showed that the bacterioplankton community is characterized by Gamma‐proteobacteria (Halomonas sp., Marinobacter sp.), Alpha‐proteobacteria (Roseobacter sp.), HGC (Agrococcus jenensis and an uncultured bacterium), and CFB (uncultured Bacteroidetes). During the day, minor modifications in bacterial diversity such as intensification of Bacteroidetes' signal and an emergence of Gamma‐proteobacteria (Marinobacter flavimaris) were observed after solar exposure. DNA damage, measured as an accumulation of Cyclobutane Pyrimidine Dimers (CPDs), in bacterioplankton and naked DNA increased from 100 CPDs MB−1 at 1200 local time (LT) to 300 CPDs MB−1 at 1600 LT, and from 80 CPDs MB−1 at 1200 LT to 640 CPDs MB−1 at 1600 LT, respectively. In addition, pure cultures of Pseudomonas sp. V1 and Brachybacterium sp. V5, two bacteria previously isolated from this environment, were exposed simultaneously with the community, and viability of both strains diminished after solar exposure. No CPD accumulation was observed in either of the exposed cultures, but an increase in mutagenesis was detected in V5. Of both strains only Brachybacterium sp. V5 showed CPD accumulation in naked DNA. These results suggest that the bacterioplankton community is well adapted to this highly solar irradiated environment showing little accumulation of CPDs and few changes in the community composition. They also demonstrate that these microorganisms contain efficient mechanisms against UV damage.
Tsunamis and splay fault dynamics
Authors: Wendt James , Oglesby David D. , Geist Eric L.
Published: August 2009

The geometry of a fault system can have significant effects on tsunami generation, but most tsunami models to date have not investigated the dynamic processes that determine which path rupture will take in a complex fault system. To gain insight into this problem, we use the 3D finite element method to model the dynamics of a plate boundary/splay fault system. We use the resulting ground deformation as a time‐dependent boundary condition for a 2D shallow‐water hydrodynamic tsunami calculation. We find that if the stress distribution is homogeneous, rupture remains on the plate boundary thrust. When a barrier is introduced along the strike of the plate boundary thrust, rupture propagates to the splay faults, and produces a significantly larger tsunami than in the homogeneous case. The results have implications for the dynamics of megathrust earthquakes, and also suggest that dynamic earthquake modeling may be a useful tool in tsunami research.
Ion and electron temperature evolution during equatorial spread F
Authors: Huba J. D. , Joyce G. , Krall J. , Fedder J.
Published: August 2009

The first simulation study of ion (O+ and H+) and electron temperature evolution during equatorial spread F (ESF) is presented. The simulation results are based on the Naval Research Laboratory (NRL) SAMI3/ESF three‐dimensional code. It is found that the ions and electrons undergo both cooling and heating during bubble evolution. The main cause of cooling is adiabatic, associated with the increase of the flux tube volume as the plasma bubble rises. Ion heating is primarily caused by the compression of ions as they stream down the converging magnetic field. The electrons are heated by collisional coupling with the ions. Additionally, it is found that the electrons are heated at high altitudes (≳1200 km) because of thermal conduction, and that hydrogen ions can be heated at relatively low altitudes (≃300 km) because of ion‐neutral frictional heating. We compare the simulation results with observations from the ROCSAT and Hinotori satellites.
Increase in background stratospheric aerosol observed with lidar at Mauna Loa Observatory and Boulder, Colorado
Authors: Hofmann David , Barnes John , O'Neill Michael , Trudeau Michael , Neely Ryan
Published: August 2009

The stratospheric aerosol layer has been monitored with lidars at Mauna Loa Observatory in Hawaii and Boulder in Colorado since 1975 and 2000, respectively. Following the Pinatubo volcanic eruption in June 1991, the global stratosphere has not been perturbed by a major volcanic eruption providing an unprecedented opportunity to study the background aerosol. Since about 2000, an increase of 4–7% per year in the aerosol backscatter in the altitude range 20–30 km has been detected at both Mauna Loa and Boulder. This increase is superimposed on a seasonal cycle with a winter maximum that is modulated by the quasi‐biennial oscillation (QBO) in tropical winds. Of the three major causes for a stratospheric aerosol increase: volcanic emissions to the stratosphere, increased tropical upwelling, and an increase in anthropogenic sulfur gas emissions in the troposphere, it appears that a large increase in coal burning since 2002, mainly in China, is the likely source of sulfur dioxide that ultimately ends up as the sulfate aerosol responsible for the increased backscatter from the stratospheric aerosol layer. The results are consistent with 0.6–0.8% of tropospheric sulfur entering the stratosphere.
Coherent multidecadal variability in North Atlantic sea level
Authors: Frankcombe L. M. , Dijkstra H. A.
Published: August 2009

Tide gauge records from around the North Atlantic are examined and found to show variability on 20–30 year time scales. Sea surface height variability along the western boundary of the North Atlantic shows a particularly strong and coherent signal. Similar variability is also found in an ensemble of runs using a state‐of‐the‐art climate model (GFDL CM2.1). This sea surface height variability is linked to variability of temperatures in the upper layers of the ocean and thence to the Atlantic Multidecadal Oscillation. The variability is consistent with the excited internal ocean mode mechanism of multidecadal variability derived from idealised models and the timescale is consistent with that derived from observations of sub‐surface temperature variability.
Generalization of n-ary Nambu algebras and beyond
Authors: Ataguema H. , Makhlouf A. , Silvestrov S.
Published: August 2009

The aim of this paper is to introduce n-ary Hom-algebra structures generalizing the n-ary algebras of Lie type including n-ary Nambu algebras, n-ary Nambu–Lie algebras and n-ary Lie algebras, and n-ary algebras of associative type including n-ary totally associative and n-ary partially associative algebras. We provide examples of the new structures and present some properties and construction theorems. We describe the general method allowing one to obtain an n-ary Hom-algebra structure starting from an n-ary algebra and an n-ary algebra endomorphism. Several examples are derived using this process. Also we initiate investigation of classification problems for algebraic structures introduced in the article and describe all ternary three-dimensional Hom–Nambu–Lie structures with diagonal homomorphism.
Characterization and merger of oscillatory mechanisms in an artificial genetic regulatory network
Authors: Yang D. , Li Y. , Kuznetsov A.
Published: August 2009

Regulatory molecular networks have numerous pharmacological and medical applications. The oscillatory mechanisms and the role of oscillations in these regulatory networks are not fully understood. In this paper, we explore two oscillatory mechanisms: the hysteresis-based relaxation oscillator and the repressilator. We combine these mechanisms into one regulatory network so that only two parameters, the strength of an additional regulatory connection and the timescale separation for one of the variables, control the transition from one mechanism to the other. Our data support a qualitative difference between the oscillatory mechanisms, but in the parameter space, we found a single oscillatory region, suggesting that the two mechanisms support each other. We examine interactions in a basic population: that is, a pair of the composite oscillators. We found that the relaxation oscillation mechanism is much more resistant to oscillatory death as the cells are diffusively coupled in a population. Additionally, stationary pattern formation has been found to accompany the relaxation oscillation but not the repressilator mechanism. These properties may guide the identification of oscillatory mechanisms in complex natural regulatory networks.
Magnetic, dielectric, magnetoelectric, and microstructural studies demonstrating improved magnetoelectric sensitivity in three-phase BaTiO3–CoFe2O4–poly(vinylidene-fluoride) composite
Authors: Gupta Arti , Chatterjee Ratnamala
Published: August 2009

A three-phase BaTiO3–CoFe2O4–poly(vinylidene-fluoride) (BT-CF-PVDF) particulate composite showing a maximum magnetoelectric voltage coefficient αE33∼26 mV/cm Oe, at a small applied magnetic field HDC=263 Oe, has been demonstrated in this work. Large magnetoelectric response in this composite (particulate BT-CF embedded in PVDF matrix) is possibly a result of the effective mechanical interaction between CF and BT through the PVDF matrix. Processing temperatures for composite preparation are low, ensuring no chemical reaction or interdiffusion between the atoms of piezoelectric and magnetostrictive phases, leading to large value of magnetoelectric voltage coefficient. Detailed measurements of dielectric, magnetic, and static magnetoelectric data are reported. Peak in the dielectric spectrum is shown to correlate with the buildup of magnetization in the composite. Although the M-H loop gives Ms, Mr, and Hc (=37.2 emu/g, 16.4 emu/g, and 830 Oe, respectively) in accordance with the expected values (wt % of CF in the composite is 52.5%), the overall magnetic behavior of the composite is identified as “spin glass.”