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  • Die Georgia Augusta feierte im September 1837 mit einem ganz Göttingen zur Bühne machenden Fest ihr Hundertjahrjubiläum. Die Feierlichkeiten dauerten drei Tage und waren glanzvoll. Um für eine breitere zeitgenössische Öffentlichkeit die Jubiläumsaktivitäten zu dokumentieren und um den Festmarathon als einen der Höhepunkte der Universitätsgeschichte für die Nachwelt festzuhalten, erschienen 1838 bei drei deutschen Verlegern in drei deutschen Städten drei Festbeschreibungen. Zwei davon halten für den Leser Überraschungen bereit: Eduard Beurmanns Prosabericht ist in höchstem Maße kritisch, ja zum Teil sogar sarkastisch, Christianus Juvenalis hat sich für eine hexametrische Satire (!) als Geburtstagsgeschenk entschieden, nur Friedrich Wilhelm Rettbergs Schilderung liegt auf der offiziellen (d.h. enkomiastischen) Linie. Das vorliegende Bändchen bietet eine vergleichende Interpretation dieser drei kulturgeschichtlich und wissenschaftspolitisch aufschlussreichen Texte, wobei der Schwerpunkt auf der Satire liegt, die in faksimilierter Form hier erstmals einer breiteren Öffentlichkeit zugänglich gemacht wird.
  • The formaldehyde molecule is an important model system for understanding dynamical processes in small polyatomic molecules. However, prior to this work, there have been no reports of a resonance-enhanced multiphoton ionization (REMPI) detection scheme for formaldehyde suitable for rovibrationally state-selective detection in molecular beam scattering experiments. Previously reported tunable REMPI schemes are either non-rotationally resolved, involve multiple resonant steps, or involve many-photon ionization steps. In the current work, we present a new 1 + 1' REMPI scheme for formaldehyde. The first photon is tunable and provides rotational resolution via the vibronically allowed à (1)A2 ← X[combining tilde] (1)A1 transition. Molecules are then directly ionized from the à state by one photon of 157 nm. The results indicate that the ionization cross section from the 4(1) vibrational level of the à state is independent of the rotational level used as intermediate, to within experimental uncertainty. The 1 + 1' REMPI intensities are therefore directly proportional to the à ← X[combining tilde] absorption intensities and can be used for quantitative measurement of X[combining tilde]-state population distributions.
  • The study aimed to quantify the color regression of enamel (E), dentine (D), and combined enamel–dentine (ED) of differently bleached ED specimens over a period of 12 months in vitro. Two ED samples were obtained from the labial surfaces of bovine teeth and prepared to a standardized thickness with the enamel and dentine layer each 1 mm. The ED samples were distributed on four groups (each n=80), in which the different bleaching products were applied on enamel (1, Whitestrips; 2, Illuminé 15%; 3, Opalescence Xtra Boost) or dentine surfaces (4, mixture of sodium perborate/distilled water). Eighty ED samples were not bleached (control). Color (L*a*b*) of ED was assessed at baseline, subsequently after bleaching and at 3, 6, and 12 months of storage after bleaching (each 20 samples/group). E and D samples were prepared by removing the dentine or enamel layer of ED samples to allow for separate color analysis. Bleaching resulted in a significant color change (ΔE) of ED specimens. Within the observation period, ΔL but not Δb declined to baseline. L* values of E and D samples also declined and were not significantly different from control samples after 12 months, while b* values did not decrease to baseline. Generally, no differences between the bleaching agents could be observed. Color change of enamel, dentine, and combined ED of in vitro bleached tooth samples is not stable over time with regard to lightness. However, yellowness did not return to baseline within 1 year.
  • The lithium derivative of tert-butyl(di-tert-butylfluorosilyl)-amine (1) reacts with sulfur or selenium to give the bis[(fluorosilyl)-amino]di- and -trisulfanes 2, 3 and -selane 4, respectively. The trisulfane 3 crystallizes from n-hexane and exhibits a helical structure (X-ray analysis).
  • Background The autosomal dominant tumor syndrome tuberous sclerosis complex is caused by the mutated TSC1 gene, hamartin, and the TSC2 gene, tuberin. Patients with this complex develop typical cutaneus symptoms such as peau chagrin or angiofibromas of the skin as well as other lesions such as astrocytomas in the brain and lymphangioleiomyomatosis in the lung. Only a few tuberous sclerosis patients have been described who showed a multifocal micronodular pneumocyte hyperplasia of the lung. Another benign tumor which often occurs together with tuberous sclerosis is the angiomyolipoma of the kidney. Furthermore, an increased incidence of renal cell carcinoma in connection with tuberous sclerosis has also been proven. Case presentation We report a 13-year-old white girl with epilepsy and hypopigmented skin lesions. Radiological studies demonstrated the typical cortical tubers leading to the diagnosis of tuberous sclerosis. In the following examinations a large number of angiomyolipomas were found in both kidneys. One lesion showed an increasing size and tumor like aspects in magnetic resonance imaging. The pathological examination of the following tumorectomy demonstrated an unclassified renal cell carcinoma. Four months postoperatively, a follow-up computer tomography revealed multiple bilateral pulmonary nodules. To exclude lung metastases of the renal cell carcinoma, multiple open-lung biopsies were performed. Conclusion Here we report a diagnostically challenging case of a 13-year-old patient with tuberous sclerosis and angiomyolipomas of the kidney who developed an unclassified renal cell carcinoma as well as multifocal micronodular pneumocyte hyperplasia.
  • N-methyl-D-aspartate receptor (NMDAR) activation induces excitotoxicity, contributing to post-stroke brain injury. Hitherto, NMDAR deactivation failed in clinical trials due to insufficient pre-clinical study designs and drug toxicity. Flupirtine is an indirect NMDAR antagonist being used as analgesic in patients. Taking into account its tolerability profile, we evaluated effects of flupirtine on post-stroke tissue survival, neurological recovery and brain remodeling. Mice were exposed to stroke and intraperitoneally treated with saline (control) or flupirtine at various doses (1-10 mg/kg) and time-points (0-12 hours). Tissue survival and cell signaling were studied on day 2, whereas neurological recovery and tissue remodeling were analyzed until day 84. Flupirtine induced sustained neuroprotection, when delivered up to 9 hours. The latter yielded enhanced neurological recovery that persisted over three months and which was accompanied by enhanced angioneurogenesis. On the molecular level, inhibition of calpain activation was noted, which was associated with increased signal-transducer-and-activator-of-transcription-6 (STAT6) abundance, reduced N-terminal-Jun-kinase and NF-κB activation, as well as reduced proteasomal activity. Consequently, blood-brain-barrier integrity was stabilized, oxidative stress was reduced and brain leukocyte infiltration was diminished. In view of its excellent tolerability, considering its sustained effects on neurological recovery, brain tissue survival and remodeling, flupirtine is an attractive candidate for stroke therapy.
  • International Journal of Production Research; Vol. 47, No. 08, p. 2079-2090. Taylor & Francis
    Zitationen bei Web of Science®: 11
    The planning of production capacity been extensively discussed in literature. Seasonal demand of products or seasonal availability of input materials can make the problem even more challenging, due to a constant need for capacity adjustments. For example, the energetic or industrial use of biomass has several distinct characteristics in contrast to conventional chemical processes, like a time dependent availability of raw materials. Therefore, suitable planning tools are required that take into account the dynamics of the production system (for example by following the seasons and the yearly changes). Thus a recently proposed heuristic approach for aggregate production planning when facing a seasonal demand is analyzed. This method is inspired by the graphical pinch analysis from chemical engineering; it is first illustrated with data from a bicycle company facing seasonal demand showing its plainness and some limitations. Then the transfer to situations with seasonal supplies of input materials is presented, as for biomass use in dynamic and seasonal markets. Using these applications, the uncomplex heuristic, its limits and its benefits are put up for discussion.
  • The iminophosphane, tBu2PPNNR2 (RSiMe3), produced by base-catalyzed elimination of ClSiMe3 from the corresponding phosphane, possesses an unusually long PN bond (162 pm), which is in accord with quantum chemical calculations.
  • Astronomy and Astrophysics; Vol. 406, No. 1, p. 253-257
    Zitationen bei Web of Science®: 15
    We present the results of 50 hours time-resolved R-band photometry of the ROSAT all-sky survey source 1RXS J062518.2+733433. The source was identified by Wei et al. (1999) as a cataclysmic variable. Our photometry, performed in 10 nights between February 11, 2003, and March 21, 2003, reveals two stable periodicities at 19.7874 and 283.118 min, which are identified as probable spin and orbital periods of the binary. We therefore classify 1RXS J062518.2+733433 as an intermediate polar. Analysis of the RASS X-ray observations reveal a variability of 100% in the X-ray flux and a likely soft X-ray excess. The new IP thus joins the rare group of soft IPs with only four members so far.
  • Alport syndrome, historically referred to as hereditary glomerulonephritis with sensorineural deafness and anterior lenticonus, is a genetic disease of collagen α3α4α5(IV) resulting in renal failure. The collagen α3α4α5(IV) heterotrimer forms a network that is a major component of the kidney glomerular basement membrane (GBM) and basement membranes in the cochlea and eye. Alport syndrome, estimated to affect 1 in 5000-10,000 individuals, is caused by mutations in any one of the three genes that encode the α chain components of the collagen α3α4α5(IV) heterotrimer: COL4A3, COL4A4, and COL4A5. Although angiotensin-converting enzyme inhibition is effective in Alport syndrome patients for slowing progression to end-stage renal disease, it is neither a cure nor an adequate long-term protector. The 2014 International Workshop on Alport Syndrome, held in Oxford, UK, from January 3-5, was organized by individuals and families living with Alport syndrome, in concert with international experts in the clinical, genetic, and basic science aspects of the disease. Stakeholders from diverse communities-patient families, physicians, geneticists, researchers, Pharma, and funding organizations-were brought together so that they could meet and learn from each other and establish strategies and collaborations for the future, with the overall aim of discovering much needed new treatments to prolong kidney function.
  • Aristaless-like homeobox 4 (ALX4) gene is an important transcription regulator in skull and limb development. In humans and mice ALX4 mutations or loss of function result in a number of skeletal and organ malformations, including polydactyly, tibial hemimelia, omphalocele, biparietal foramina, impaired mammary epithelial morphogenesis, alopecia, coronal craniosynostosis, hypertelorism, depressed nasal bridge and ridge, bifid nasal tip, hypogonadism, and body agenesis. Here we show that a complex skeletal malformation of the hind limb in Galloway cattle together with other developmental anomalies is a recessive autosomal disorder most likely caused by a duplication of 20 bp in exon 2 of the bovine ALX4 gene. A second duplication of 34 bp in exon 4 of the same gene has no known effect, although both duplications result in a frameshift and premature stop codon leading to a truncated protein. Genotyping of 1,688 Black/Red/Belted/Riggit Galloway (GA) and 289 White Galloway (WGA) cattle showed that the duplication in exon 2 has allele frequencies of 1% in GA and 6% in WGA and the duplication in exon 4 has frequencies of 23% in GA and 38% in WGA. Both duplications were not detected in 876 randomly selected German Holstein Friesian and 86 cattle of 21 other breeds. Hence, we have identified a candidate causative mutation for tibial hemimelia syndrome in Galloway cattle and selection against this mutation can be used to eliminate the mutant allele from the breed.
  • World Journal of Microbiology and Biotechnology; Vol. 27, No. 9, p. 2071-2079. Springer Netherlands
    Zitationen bei Web of Science®: 6
    2,4-Diacetylphloroglucinol (DAPG) produced by Pseudomonas fluorescens, shows toxicity to many microorganisms including fungi, bacteria, and peronosporomycetes. Zoosporogenesis and motility of zoospores are critical for a complete disease cycle and pathogenicity of the peronosporomycete phytopathogens. The aim of this study was to test the effects of DAPG and its derivatives on zoosporogenesis and motility of zoospores of a downy mildew pathogen, Plasmopara viticola, and a damping-off pathogen, Aphanomyces cochlioides. In both cases, DAPG inhibited zoosporogenesis (5 μg/ml) and the motility of zoospores (10 μg/ml) in a dose-dependent manner. Generally, zoospores became immotile shortly after exposure to DAPG followed by lysis. However, a fraction of DAPG treated A. cochlioides zoospores formed round cystospores instead of lysis and then germinated with excessively-branched germ tubes. All derivatives of DAPG had similar inhibitory activities but at varying doses. Among them, 2,4-dipropylphloroglucinol exerted the highest inhibitory activity against both zoosporogenesis and motility of zoospores. This revealed that the degree of hydrogen atoms substitution in the benzene ring by acyl groups and the length of substituted acyl groups were related to the level of bioactivity. This is the first report of inhibitory activities of DAPG and its derivatives against zoosporogenesis and motility of zoospores of two important peronosporomycete phytopathogens.
  • Aus Reaktionen subvalenter Species, die durch die Reaktion von Dichlor(diisopropylamino)boran mit Natrium/Kalium Legierung entstehen, mit ungesättigten aliphatischen Kohlenwasserstoffen, wurden folgende Verbindungen isoliert: Mit 1,3-Dienen die 2,5-Dihydroborole I und II; mit Alkinen die 1,3-Dihydro-1,3-diborete III und IV und mit Bis(trimethylsilyl)ethin das 1-Bis(diisopropylamino)boryl-2-trimethylsilylethin V. Die Verbindungen sind elementaranalytisch, spektroskopisch (Mp. NMR: 1H, 11B und 13C, zum Teil auch 15N und 29Si) charakterisiert. Von II wurde eine Röntgenstrukturanalyse angefertigt. Abstract: The reactions of subvalent species generated by the reaction of dichloro(diisopropylamino)borane with sodium/potassium alloy with unsaturated aliphatic hydrocarbons, have yielded the following compounds: the 2,5-dihydroboroles I and II from 1,3-dienes; the 1,3-dihydrodiboretes III and IV from alkynes and the 1-bis(diisopropylamino)boryl-2-trimethylsilylethyne V from bis(trimethylsilyl)ethyne. The compounds have been characterized by elemental analyses and by mass and NMR (1H, 11B, 13C and in part 15N and 29Si) spectroscopy. An X-ray diffraction study has been performed on II.
  • Ethik in der Medizin; Vol. 23, No. 3, p. 175-176. Springer-Verlag
  • Astronomy and Astrophysics; Vol. 378, No. 3, p. 1078-1086
    Zitationen bei Web of Science®: 31
    The radial variation of the Evershed flow in two small sunspots (NOAA 8737 and NOAA 9145) is studied by means of two-dimensional spectrograms of high spatial resolution. We find a systematic decrease of the flow velocity with photospheric height and a shift of the velocity maximum towards larger penumbral radii in higher layers but no clear correlation between flow velocity and continuum intensity. At the outer penumbral boundaries the Evershed flow ceases abruptly and even downward directed flow velocities in the deepest probed photospheric layers were found. Furthermore, granules adjacent to the penumbral boundary show a systematic redshift of their spot-side parts which is attributed to fast, eventually supersonic, downflows between them and the penumbral boundary.
  • Astronomy and Astrophysics; Vol. 473, No. 3, p. 761-770
    Zitationen bei Web of Science®: 21
    We investigate distortions in the velocity fields of disc galaxies and their use in revealing the dynamical state of interacting galaxies at different redshifts. We model disc galaxies in combined N-body/hydrodynamic simulations. 2D velocity fields of the gas are extracted, which we place at different redshifts from z=0 to z=1 to investigate resolution effects on the properties of the velocity field. To quantify the structure of the velocity field we also perform a kinemetry analysis. If the galaxy is undisturbed we find that the rotation curve extracted from the 2D field agrees well with long-slit rotation curves. This is not true for interacting systems, as the kinematic axis is not well defined and in general does not coincide with the photometric axis of the system. For large (Milky way type) galaxies we find that distortions are still visible at intermediate redshifts but are partly smeared out. Thus a careful analysis of the velocity field is necessary before using it for a Tully-Fisher study. For small galaxies (disc scale length ~2 kpc) even strong distortions are not visible in the velocity field at $z\approx0.5$ with currently available angular resolution. Therefore we conclude that current distant Tully-Fisher studies cannot give reliable results for low-mass systems. Additionally we confirm the power of near-infrared integral field spectrometers in combination with adaptive optics (such as SINFONI) to study velocity fields of galaxies at high redshift ($z\sim2$).
  • We report the discovery of a new eclipsing system less than one arcminute south of the pulsating DB white dwarf KUV05134+2605. The object could be identified with the point source 2MASSJ0516288+260738 published by the Two Micron All Sky Survey.We present and discuss the first light curves as well as some additional colour and spectral information. The eclipse period of the system is 1.29 d, and, assuming this to be identical to the orbital period, the best light curve solution yields a mass ratio of m2/m1 = 0.11, a radius ratio of r2/r1 ≈ 1 and an inclination of 74◦. The spectral anaylsis results in a Teff = 4200 K for the primary. On this basis, we suggest that the new system probably consists of a late K + Brown dwarf (which would imply a system considerably younger than ≈0.01 Gyr to have r2/r1 ≈ 1), and outline possible future observations.
  • It is claimed that wound closure with 2-octyl-cyanoacrylate has the advantages that band-aids are not needed in the postoperative period, that the wound can get in contact with water and that removal of stitches is not required. This would substantially enhance patient comfort, especially in times of reduced in-hospital stays. Postoperative wound infection is a well-known complication in spinal surgery. The reported infection rates range between 0% and 12.7%. The question arises if the advantages of wound closure with 2-octyl-cyanoacrylate in spinal surgery are not surpassed by an increase in infection rate. This study has been conducted to identify the infection rate of spinal surgery if wound closure was done with 2-octyl-cyanoacrylate. A total of 235 patients with one- or two-level surgery at the cervical or lumbar spine were included in this prospective study. Their pre- and postoperative course was evaluated. Analysis included age, sex, body mass index, duration and level of operation, blood examinations, 6-week follow-up and analysis of preoperative risk factors. The data were compared to infection rates of similar surgeries found in a literature research and to a historical group of 503 patients who underwent wound closure with standard skin sutures after spine surgery. With the use of 2-octyl-cyanoacrylate, only one patient suffered from postoperative wound infection which accounts for a total infection rate of 0.43%. In the literature addressing infection rate after spine surgery, an average rate of 3.2% is reported. Infection rate was 2.2% in the historical control group. No risk factor could be identified which limited the usage of 2-octyl-cyanoacrylate. 2-Octyl-cyanoacrylate provides sufficient wound closure in spinal surgery and is associated with a low risk of postoperative wound infection.
  • Efficient and scalable syntheses of enantiomerically pure (2R,1'S,2'R)- and (2S,1'S,2'R)-3-[2-mono(di,tri)fluoromethylcyclopropyl]alanines 9a-c, as well as allo-D-threonine (4) and (2S,3R)-β-methylphenylalanine (3), using the Belokon' approach with (S)- and (R)-2-[(N-benzylprolyl)amino]benzophenone [(S)- and (R)-10] as reusable chiral auxiliaries have been developed. Three new fluoromethyl analogues of the naturally occurring octadepsipeptide hormaomycin (1) with (fluoromethylcyclopropyl)alanine moieties have been synthesized and subjected to preliminary tests of their antibiotic activity.



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