AGROBACTERIUM VIRB10 CONTRIBUTIONS TO TYPE IV SUBSTRATE SECRETION, T-PILUS BIOGENESIS, AND OUTER MEMBRANE PORE FORMATION

The VirB/D4 type IV secretion system (T4SS) of Agrobacterium tumefaciens functions to transfer substrates to infected plant cells through assembly of a translocation channel and a surface structure termed a T-pilus. This thesis is focused on identifying contributions of VirB10 to substrate transfer and T-pilus formation through a mutational analysis. VirB10 is a bitopic protein with several domains, including a: (i) cytoplasmic N-terminus, (ii) single transmembrane (TM) α-helix, (iii) proline-rich region (PRR), and (iv) large C-terminal modified β-barrel. I introduced cysteine insertion and substitution mutations throughout the length of VirB10 in order to: (i) test a predicted transmembrane topology, (ii) identify residues/domains contributing to VirB10 stability, oligomerization, and function, and (iii) monitor structural changes accompanying energy activation or substrate translocation. These studies were aided by recent structural resolution of a periplasmic domain of a VirB10 homolog and a ‘core’ complex composed of homologs of VirB10 and two outer membrane associated subunits, VirB7 and VirB9. By use of the substituted cysteine accessibility method (SCAM), I confirmed the bitopic topology of VirB10. Through phenotypic studies of Ala-Cys insertion mutations, I identified “uncoupling” mutations in the TM and β-barrel domains that blocked T-pilus assembly but permitted substrate transfer. I showed that cysteine replacements in the C-terminal periplasmic domain yielded a variety of phenotypes in relation to protein accumulation, oligomerization, substrate transfer, and T-pilus formation. By SCAM, I also gained further evidence that VirB10 adopts different structural states during machine biogenesis. Finally, I showed that VirB10 supports substrate transfer even when its TM domain is extensively mutagenized or substituted with heterologous TM domains. By contrast, specific residues most probably involved in oligomerization of the TM domain are required for biogenesis of the T-pilus.

Headache and transient aphasia in a 35-year-old female patient

We describe the case of a 35-year-old female patient who suffered from fulminant tick-borne encephalitis and subsequently died. Remarkable about this case was that the woman was not living in an endemic area and that the disease occurred outside the usual season. Furthermore, this indicates that an increase in transmission of tick-borne encephalitis can be expected outside the classical endemic areas in higher altitudes, possibly as a consequence of climate changes.

Geschichte der Juden in C��ln und Umgebung : aus ältester Zeit bis auf die Gegenwart ; nach hs. u. gedr. Quellen bearb.

von Carl Brisch

Shoresh davar oder Hebreisches Wörter-Buch : welches der eigentlichen Bedeutung der hebreischen Wörter in der Heiligen Schrift und auch dem geistlichen Sinn derselben als der Wurtzel des Worts der göttlichen Verheissung ... nachforschet

von Ludwig Christoph Schefer

De invaliditate librorum mercaturam concernentium Iudaica lingua conscriptorum ...

Marburg, Univ., Diss., 1766

Cyclooxygenase-2 and 5-lipoxygenase in dogs with chronic enteropathies.

BACKGROUND Cyclooxygenase-2 (COX-2) is a key enzyme in the synthesis of pro-inflammatory prostaglandins and 5-lipoxygenase (5-LO) is the major source of leukotrienes. Their role in IBD has been demonstrated in humans and animal models, but not in dogs with chronic enteropathies (CCE). HYPOTHESIS COX-2 and 5-LO are upregulated in dogs with CCE. ANIMALS Fifteen healthy control dogs (HCD), 10 dogs with inflammatory bowel disease (IBD), and 15 dogs with food-responsive diarrhea (FRD). METHODS Prospective study. mRNA expression of COX-2, 5-LO, IL-1b, IL-4, IL-6, TNF, IL-10 and TFG-β was evaluated by quantitative real-time RT-PCR in duodenal and colonic biopsies before and after treatment. RESULTS COX-2 expression in the colon was significantly higher in IBD and FRD before and after treatment (all P < .01). IL-1b was higher in FRD in the duodenum after treatment (P = .021). TGF-β expression was significantly higher in the duodenum of HCD compared to FRD/IBD before treatment (both P < .001) and IBD after treatment (P = .012). There were no significant differences among groups and within groups before and after treatment for IL-4, IL-6, TNF, and IL-10. There was a significant correlation between COX-2 and IL-1b in duodenum and colon before treatment in FRD and IBD, whereas 5-LO correlated better with IL-6 and TNF. IL-10 and TGF-β usually were correlated. CONCLUSIONS AND CLINICAL IMPORTANCE COX-2 is upregulated in IBD and FRD, whereas IL-1b and TGF-β seem to be important pro- and anti-inflammatory cytokines, respectively. The use of dual COX/5-LO inhibitors could be an interesting alternative in the treatment of CCE.

OSL-thermochronometry of feldspar from the KTB borehole, Germany

The reconstruction of thermal histories of rocks (thermochronometry) is a fundamental tool both in Earth science and in geological exploration. However, few methods are currently capable of resolving the low-temperature thermal evolution of the upper ∼2 km of the Earth's crust. Here we introduce a new thermochronometer based on the infrared stimulated luminescence (IRSL) from feldspar, and validate the extrapolation of its response to artificial radiation and heat in the laboratory to natural environmental conditions. Specifically, we present a new detailed Na-feldspar IRSL thermochronology from a well-documented thermally-stable crustal environment at the German Continental Deep Drilling Program (KTB). There, the natural luminescence of Na-feldspar extracted from twelve borehole samples (0.1–2.3 km depth, corresponding to 10–70 °C) can be either (i) predicted within uncertainties from the current geothermal gradient, or (ii) inverted into a geothermal palaeogradient of 29 ± 2  °C���km−1, integrating natural thermal conditions over the last ∼65 ka. The demonstrated ability to invert a depth–luminescence dataset into a meaningful geothermal palaeogradient opens new venues for reconstructing recent ambient temperatures of the shallow crust (<0.3 Ma, 40–70 °C range), or for studying equally recent and rapid transient cooling in active orogens (<0.3 Ma, >200 °C���Ma−1 range). Although Na-feldspar IRSL is prone to field saturation in colder or slower environments, the method's primary relevance appears to be for borehole and tunnel studies, where it may offer remarkably recent (<0.3 Ma) information on the thermal structure and history of hydrothermal fields, nuclear waste repositories and hydrocarbon reservoirs.

Zur Geschichte der Juden in Mähren und Oesterr.-Schlesien mit Rücksicht auf Oesterreich-Ungarn überhaupt und die Nachbarländer

von Christian Ritter d'Elvert

Global carbon budget 2013

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates, consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil-fuel combustion and cement production (EFF) are based on energy statistics, while emissions from land-use change (ELUC), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (GATM) is computed from the annual changes in concentration. The mean ocean CO2 sink (SOCEAN) is based on observations from the 1990s, while the annual anomalies and trends are estimated with ocean models. The variability in SOCEAN is evaluated for the first time in this budget with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (SLAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models forced by observed climate, CO2 and land cover change (some including nitrogen–carbon interactions). All uncertainties are reported as ± 1 σ, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2003–2012), EFF was 8.6 ± 0.4 GtC yr − 1, ELUC 0.9 ± 0.5 GtC yr − 1, GATM 4.3 ± 0.1 GtC yr − 1, S OCEAN 2.5 ± 0.5 GtC yr − 1, and S LAND 2.8 ± 0.8 GtC yr − 1. For year 2012 alone, EFF grew to 9.7 ± 0.5 GtC yr − 1, 2.2 % above 2011, reflecting a continued growing trend in these emissions, GATM was 5.1 ± 0.2 GtC yr − 1, SOCEANwas 2.9 ± 0.5 GtC yr −1, and assuming an ELU Cof 1.0 ± 0.5 GtC yr − 1 (based on the 2001–2010 average), SLAND was 2.7 ± 0.9 GtC yr − 1. GATM was high in 2012 compared to the 2003–2012 average, almost entirely reflecting the high EFF. The global atmospheric CO2 con- centration reached 392.52 ± 0.10 ppm averaged over 2012. We estimate that EFF will increase by 2.1 % (1.1–3.1 %) to 9.9 ± 0.5 GtC in 2013, 61 % above emissions in 1990, based on projections of world gross domestic product and recent changes in the carbon intensity of the economy. With this projection, cumulative emissions of CO2 will reach about 535 ± 55 GtC for 1870–2013, about 70 % from EFF (390 ± 20 GtC) and 30 % from ELUC (145 ± 50 GtC). This paper also documents any changes in the methods and data sets used in this new carbon budget from previous budgets (Le Quéré et al., 2013). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center.

Plasma environment of a weak comet – Predictions for Comet 67P/Churyumov–Gerasimenko from multifluid-MHD and Hybrid models

The interaction of a comet with the solar wind undergoes various stages as the comet’s activity varies along its orbit. For a comet like 67P/Churyumov–Gerasimenko, the target comet of ESA’s Rosetta mission, the various features include the formation of a Mach cone, the bow shock, and close to perihelion even a diamagnetic cavity. There are different approaches to simulate this complex interplay between the solar wind and the comet’s extended neutral gas coma which include magnetohydrodynamics (MHD) and hybrid-type models. The first treats the plasma as fluids (one fluid in basic single fluid MHD) and the latter treats the ions as individual particles under the influence of the local electric and magnetic fields. The electrons are treated as a charge-neutralizing fluid in both cases. Given the different approaches both models yield different results, in particular for a low production rate comet. In this paper we will show that these differences can be reduced when using a multifluid instead of a single-fluid MHD model and increase the resolution of the Hybrid model. We will show that some major features obtained with a hybrid type approach like the gyration of the cometary heavy ions and the formation of the Mach cone can be partially reproduced with the multifluid-type model.