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This paper reports the first successful synthesis and the structural characterization of nanocrystalline and stacking-disordered β-cristobalite AlPO4that is chemically stabilized down to room temperature and free of crystalline impurity phases. Several batches of the title compound were synthesized and thoroughly characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectroscopy mapping in SEM, solid-state 31P nuclear magnetic resonance (31P-NMR) spectroscopy including the TRAPDOR method, differential thermal analysis (DTA), gas-sorption methods, optical emission spectroscopy, X-ray fluorescence spectroscopy, and ion chromatography. Parameters that are critical for the synthesis were identified and optimized. The synthesis procedure yields reproducible results and is well documented. A high-quality XRD pattern of the title compound is presented, which was collected with monochromatic copper radiation at room temperature in a wide 2θrange of 5°–100°.

Long-term genetic data from intensively monitored natural populations are important for understanding how effective population sizes (Ne) can vary over time. We therefore genotyped 1622 common buzzard (Buteo buteo) chicks sampled over 12 consecutive years (2002–2013 inclusive) at 15 microsatellite loci. This data set allowed us to both compare single-sample with temporal approaches and explore temporal patterns in the effective number of parents that produced each cohort in relation to the observed population dynamics. We found reasonable consistency between linkage disequilibrium-based single-sample and temporal estimators, particularly during the latter half of the study, but no clear relationship between annual Neestimates () and census sizes. We also documented a 14-fold increase in between 2008 and 2011, a period during which the census size doubled, probably reflecting a combination of higher adult survival and immigration from further afield. Our study thus reveals appreciable temporal heterogeneity in the effective population size of a natural vertebrate population, confirms the need for long-term studies and cautions against drawing conclusions from a single sample.

Cuckoos (family Cuculidae) show the highest diversity of breeding strategies within one bird family (parental care, facultative and obligate brood parasites). We used independent contrasts from two phylogenies to examine how this variation was related to 13 ecological and life–history variables. The ancestral state was probably tropical, resident, forest cuckoos with parental care. The evolution of brood parasitism was correlated with a shift to more open habitats, a change in diet, increases in species breeding–range size and migration, and a decrease in egg size. Once parasitism had evolved, more elaborate parasitic strategies (more harmful to host fitness) were correlated with decreased egg size, a change in diet, increased breeding–range size and migration, a shortened breeding season and a decrease in local abundance. Establishing the most probable evolutionary pathways, using the method of Pagel, shows that changes in ecological variables (such as migration, range size and diet type) preceded the evolution of brood parasitism, which is likely to be a later adaptation to reduce the cost of reproduction. By contrast, brood parasitism evolved before changes in egg size occurred, indicating that egg size is an adaptive trait in host–parasite coevolution. Our results suggest that the evolution of cuckoo brood parasitism reflects selection from both ecological pressures and host defences.

Intercellular communication is not only mediated by extracellular transmitters, but also directly by gap junction channels. One channel is composed of two hexameric hemichannels which consist of six polypeptide subunits called connexines (Cx). In the mammalian heart the following connexines have been documented: Cx37, Cx40, Cx43, Cx45, Cx46, Cx50 and Cx57. The labeling by number represents the rounded, molecular mass of the amino acid sequences given in kD. If identical connexin-isotypes form both connexons of a gap junction channel, homotypic coupling exists and a homomeric gap junction channel is formed. Different connexin-isotypes within both connexons cause form heterotypic coupling and heteromeric gap junction channels. Each channel type has specific properties regarding permeability and electrical conductance. Beside a typical age-dependent alignement of gap junction channels on the surface of the cardiac myocytes, regional distribution of the different connexins is different at distinct parts of the mouse heart. Cx40 is not found in the ventricular working myocardium of mice. In the atria as well as in the conduction system, Cx40 is the most frequently expressed. In line with the localization and the conduction properties of distinct homotypic gap junction channels, the Cx40 deficient mouse is suitable for analysis of atrial arrhythmias. Cx40-deficiency in the mouse heart results in characteristic ECG changes like first degree atrioventricular block and prolongation of the QRS duration. Thus, an impairment of the sinuatrial, intraatrial and atrioventricular conduction properties is documented in Cx40 deficient mice. These observations are associated with an increased atrial vulnerability.¶ ??The Cx40 deficient mouse provides a good example of the relevance of transgenic mouse models to clarify the mechanisms of arrhythmogenesis. The clinical impact of future transgenic mouse models depends on the cooperation of geneticists, basic researchers and clinicians. Benachbarte Zellen in einem Zellverband kommunizieren nicht nur über extrazelluläre Botenstoffe, sondern auch über eine über Gap-Junction-Kanäle vermittelte direkte Kopplung. Ein Gap-Junction-Kanal besteht aus jeweils zwei Halbkanälen, den Connexonen, welche ihrerseits aus sechs Proteinuntereinheiten, den Connexinen (Cx) bestehen. Im Herzen wurden bisher die Connexin-Proteine Cx37, Cx40, Cx43, Cx45, Cx46, Cx50 und Cx57 nachgewiesen. Die Zahlen-Bezeichnung entspricht der aus der Aminosäuren-Sequenz errechneten, abgerundeten Molekülmasse in kilo Daltons. Identische Connexin-Isotypen innerhalb eines Connexons und innerhalb beider Connexone des Gap-Junction-Kanals bilden eine homotypische Koppelung und einen homomeren Gap-Junction-Kanal. Unterschiedliche Connexin-Isotopen führen zur heterotypischen Kopplung und zu heterotypischen Gap-Junction-Kanälen. Die verschiedenen Connexin-Isotypen verleihen den Gap-Junction-Kanälen spezifische Eigenschaften im Hinblick auf Permeabilität und elektrische Leitfähigkeit. Neben einer typischen Membranlokalisation der Gap-Junction-Kanäle in der Myokardzelle bestehen zusätzlich noch regionale Unterschiede der Connexine innerhalb einzelner Herzstrukturen. Cx40 wird nicht im Arbeitsmyokard des Ventrikels bei der Maus nachgewiesen. Im Vorhofmyokard und im Erregungsleitungssystem ist das Cx40 vorherrschend. Entsprechend der Lokalisation und der Leitungseigenschaften der einzelnen Gap-Junction-Kanäle eignet sich die Cx40-defiziente Maus zur Analyse von Vorhofrhythmusstörungen. Cx40-Defizienz verursacht charakteristische Oberflächen-EKG-Veränderungen im Sinne eines atrioventrikulären Blocks 1. Grades sowie einer Verbreiterung des QRS-Komplexes. In Übereinstimmung mit diesen Befunden werden bei der Cx40-defizienten Maus sinuatriale, intraatriale und atrioventrikuläre Leitungsverzögerungen und eine gesteigerte atriale Vulnerabilität beobachtet.¶ ??Die Cx40-defiziente Maus ist ein gutes Beispiel für die Bedeutung transgener Mausmodelle in der Rhythmologie. Die klinische Relevanz zukünftiger transgener Mausmodelle kann nur durch die Zusammenarbeit von Genetikern, Grundlagenforschern und Kliniker erarbeitet werden.

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The recombination activity of crystal defects was studied along cross-sections of cleaved multicrystalline silicon wafers (Silso®) grown by block casting. The temperature dependence of the electron-beam-induced current (EBIC) contrast c(T) was analyzed to study defect passivation by remote hydrogen plasma treatment with respect to (i) the extension and (ii) the degree of passivation. Based upon model calculations, the c(T) behavior allows estimating the degree of contamination of recombination active crystal defects. After hydrogen treatment of 1 h at 310 °C the number of defect-related deep levels at grain boundaries is reduced by a factor of three to four. Low-temperature EBIC reveals that hydrogenation also reduces the density of active centers at defects which exhibit already very low or no (detectable) EBIC contrast at room temperature such as intragrain defects. Both defects in intragrain regions and grain boundaries are passivated down to about 100 μm. No indications were found for significantly enhanced hydrogen diffusion along grain boundaries.

In order to reveal the biological function(s) of the gap-junction protein connexin 45 (Cx45), we generated Cx45-deficient mice with targeted replacement of the Cx45-coding region with the lacZ reporter gene. Heterozygous Cx45(+/)(-) mice showed strong expression of the reporter gene in vascular and visceral smooth muscle cells. Cx45-deficient embryos exhibited striking abnormalities in vascular development and died between embryonic day (E) 9.5 and 10.5. Differentiation and positioning of endothelial cells appeared to be normal, but subsequent development of blood vessels revealed impaired formation of vascular trees in the yolk sac, impaired allantoic mesenchymal ingrowth and capillary formation in the labyrinthine part of the placenta, and arrest of arterial growth, including a failure to develop a smooth muscle layer surrounding the major arteries of the embryo proper. As a consequence, the hearts of most Cx45-deficient embryos were dilated. The abnormal development of the vasculature in the yolk sac of Cx45(-)(/)(-) embryos could be caused by defective TGFbeta signalling, as the amount of TGF beta1 protein in the epithelial layer of the yolk sac was largely decreased in the E9.5 Cx45(-)(/)(-) embryo, compared with the wild-type embryo. The defective vascular development was accompanied by massive apoptosis, which began in some embryos at E8.5 and was abundant in virtually all tissues of the embryos at E9.5. We conclude that in Cx45(-)(/)(-) embryos, vasculogenesis was normal, but subsequent transformation into mature vessels was interrupted. Development of different types of vessels was impaired to a varying extent, which possibly reflects the complementation by other connexin(s).

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The genetic population structures of the freshwater snail Bulinus globosus and its trematode parasite Schistosoma haematobium from 8 river sites in the Zimbabwean highveld were compared using randomly amplified DNA(RAPD) markers. There was significant variability between snail populations collected at different sites, but schistosome populations only showed differentiation at a wider geographical scale (between 2 non-connected river systems). For snails, genetic distance was better correlated with proximity along rivers than absolute geographical separation. In contrast, schistosome genetic distance was better correlated with absolute geographical separation than proximity along rivers. These results are consistent with different dispersal mechanisms for snails and schistosomes and the implications for host–parasite coevolution are discussed.

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This study aimed to examine regional urban-rural differences in mortality from ischaemic heart disease, including sudden death of unknown cause (IHD/SUD) in Norway from 1966-89, for men and women aged 30-69 years.

Summary In order to further elucidate the pathogenesis of the direct carotid cavernous fistulas (dCCF) clinical, patho-anatomical, and physicomechanical studies were performed.

Blood samples of people from three Mediterranean countries were investigated for different enzyme polymorphisms. The following gene frequencies were found:

Human fascia has been examined with the aid of a universal test equipment as to its mechanical properties in relation to age, conservation and texture.

Broadband transmitters for radio links in the millimeter band are key building blocks for future wireless communication systems. Such components can be realized by means of an InP-on-BiCMOS technology. This allows the combination of the high performance of III-V transistors with the advantages of BiCMOS circuits. Critical performance trade-offs can be avoided in comparison to the pure III-V or BiCMOS versions. The passive elements and the interconnections between InP and BiCMOS were fabricated in a first run. The results are shown in the present work. This run showed the feasibility of the wafer bond process for the hetero-integration of InP and BiCMOS. An aluminum back-end was built on the silicon wafer with silicon dioxide as interlayer dielectric. A gold metallization in benzocyclobutene (BCB) as insulating dielectric represented the environment for the InP hetero-junction bipolar transistors. Thin film micro strip lines and specially designed interconnections between the two metallization systems were characterized in dependence on frequencies up to 100 GHz.

Approaches towards fast switching GaN devices for applications in power electronics are discussed. First, an overview on the most prominent techniques towards increased breakdown voltage will be given for devices grown on SiC and Si substrates. These tech-niques will then be set in relation to dynamic switching properties at different bias voltage levels. Dynamic switching properties are still lagging behind competing devices, especially if switching at high bias levels is considered. The switching properties are usually expressed by the so-called dynamic on-state resistance. It signifi-cantly depends on technological parameters such as epitaxial layer design and crystalline quality of the buffer layer, passivation layers and, last but not least the lateral device designs (e.g. field plate ar-rangements). A balanced trade-off between all these influencing quantities is shown and correlated to current state of GaN high voltage switching devices.

Summary A total of 180 jugular-venous cathethers (Cavafix Certo GS, Frekathether Pur, Vygoflex-in, Alpha Set J 30) were clinically tested under prospective standardized conditions (experimental flow, elasticity, thrombin-formation, X-ray contrast, puncture characteristics) Polyurethane (Cavafix Certo, Frekatheter Pur) proved to be of a high quality, especially with respect to flow and thrombin-producing ability. Vena cava catheters, with laterally situated outflow holes, have an increased outflow area and are therefore superior to the other catheters in this respect. The polyethylene catheters showed increased activity during radio-fibrinogen testing in vitro — a sign of thrombin formation.