Coma imaging of comet P/Brorsen-Metcalf at Calar Alto in late July to mid August 1989

Comet P/Brorsen-Metcalf was observed on 1989/07/28+30 and on 1989/08/04+12(+14) with the 3.5 m telescope and the 0.8 m Schmidt camera at Calar Alto/Spain. The images exhibit a narrow plasma tail pointing into anti-solar direction. On 1989/07/30 a triple tail was found which can be interpreted as tail ray event. The coma isophotes show prominent asymmetries with the nucleus located on the tailward side of the isophote foci and with a slightly higher brightness in the Northern Hemisphere of the coma. A strong curved jet feature was detected in the coma on 1989/07/30. The jet extended at least 30,000 km into the sunward coma hemisphere. The rotation period of about 1.3 days, estimated from the curvature of the coma jet, needs verification by other observations

Introduction : Waging Health: Women in Nineteenth-Century American Wars

Thinking of war from a U.S.-American perspective will almost immediately evoke associations of male soldiers fighting heroic battles for a good cause such as democracy and/or the liberation of people from dictatorships, tyrannies, and torture. However, as more detailed and on-site news coverage has increasingly shown, this vision is entirely too limited. Among many possible revisionist perspectives is that of those women who have been involved in wars from a medical point of view and have sig..

"The significance of sensomotoric-coordinative abilities for improvement of golfing performance of junior golfers"

Zusammenfassung "Die Bedeutung sensomotorisch-koordinativer Fähigkeiten für die Verbesserung von Golfleistungen im Nachwuchsbereich" In dieser Arbeit werden Verbesserungen von Golfleistungen im Nachwuchsbereich mittels "sensomotorisch-koordinativen Trainings" untersucht. Es wird anhand von sechs neu entwickelten golfspezifischen Testparametern festgestellt, ob sich durch das sensomotorisch-koordinative Training die Golfleistungen verbessern können. Neben den eingesetzten Testparametern wird zur Feststellung von Spielverbesserungen (beschleunigte Lernfortschritte) das DGV Vorgabensystem eingesetzt. Für das methodische Vorgehen werden fünf verschiedene Einzelgruppen einschließlich einer Kontrollgruppe mit quantitativen Messungen (Vorher-Nachher) erfasst. Mit Hilfe eines Leitfadeninterviews mit vier ausgewählten Fragen werden die Teilnehmer außerdem zum sensomotorisch-koordinativen Training befragt, um festzustellen, inwieweit sich das Training auf die intrinsische Motivation und der Freude im Training auswirkt. Bei der Frage, ob die Probanden das sensomotorisch-koordinative Training über den Untersuchungszeitraum hinaus selbstständig weiterführen würden, entschieden sich 91 % der Probanden dafür, diesen Aspekt in ihrem eigenen Training künftig weiter anzuwenden, wobei auch die bevorzugten Übungen genannt wurden. Ergebnisse der Einzelgruppen (Vorher-Nachher) werden ausgewertet und analysiert. Danach erfolgt aus den Ergebnissen der Einzelgruppen und den Gruppenvergleichen sowie den qualitativen Aussagedaten eine Interpretation der Untersuchungen. Aus den vorhandenen Ergebnissen kann gefolgert werden, dass das sensomotorisch-koordinative Training die Golfleistungen (Technik-anwendung) und die Lernfortschritte im Golfspiel beschleunigt. Ein Nachwuchsspieler kann im Rahmen seines Techniktrainings individuell große Fortschritte machen und mittel- und langfristig seine Spielstärke (HCP) im Leistungsaufbau ständig verbessern. Begleitend zum Trainingsalltag wird die Freude am Lernen gesteigert. Mehr Motivation erhöht die Bereitschaft, komplexe Aufgaben/Herausforderungen (golfspezifische Situationen) von innen heraus (intrinisch) zu lösen. Um den präventiven Charakter im gesamten Nachwuchssport zu erhalten, sollte das sensomotorisch-koordinative Training von der Grundausbildung bis zum Hochleistungssport ein immer zu trainierender Part im sportartspezifischen Training sein. Dies gilt im besonderen Sinne für Nachwuchsgolfer. Das sensomotorisch-koordinative Training sollte altersgemäß und der Leistungsstärke der jeweiligen Trainingsgruppe angepasst und standardisiert werden. So können im langfristigen Leistungsaufbau die Lernerfolge nachhaltig ausgebaut und gesichert werden.Abstract "The significance of sensomotoric-coordinative abilities for improvement of golfing performance of junior golfers" This study investigates the improvements of golfing performance of junior golfers using "sensomotoric-coordinative training". Employing six newly developed golf-specific test parameters it will be determined whether golfing abilities can be improved by sensomotoric-coordinative training exercises. To quantify the gaming improvements (accelerated learning progress) the DGV handicap system is used in addition to the test parameters. For the methodical approach, five different individual groups plus a control group are gauged by quantitative measurements (before-after). By means of a guided interview including four selected questions the participants are additionally interrogated about their sensomotoric-coordinative training to determine to what extent the training impacts on the intrinsic motivation and enjoyment of training. On the issue whether the test persons might independently continue the sensomotoric-coordinative training beyond the evaluation period 91 % of them declare to further include this aspect in the own training in future, also stating their preferred exercises. The results of the individual groups (before-after) are evaluated and analyzed. The investigations are then interpreted using the group results and comparisons as well as the qualitative statement data. The existing results support the conclusion that sensomotoric-coordinative training improves the golfing performance (application of techniques) and expedites the learning process in golfing. Junior golfers may achieve good individual progress within the scope of his or her technical training and continually improve their play level (handicap) during the medium - and long-term performance build-up. Enjoyment in learning increases, joining the everyday training. Higher motivation heightens the willingness to resolve complex tasks and challenges (in golfing-specific situations) "from within", i.e. intrinsically. To maintain the preventive character in the entire youth sports area, sensomotoric-coordinative training should remain an essential training aspect from basic golfing training through to high-performance sport, in particular for junior golfers. Sensomotoric-coordinative training should be specifically tailored and standardized to the trainees' age group and performance level. This will allow to sustainably increase and secure the learning achievements during the long-term performance building

Síntesis, reactividad, estructura y propiedades de compuestos de metales del grupo del platino con enlaces M-N amido, amino e imino. ataques nucleofílicos sobre iminas coordinadas a paladio

El trabajo se centra en el estudio del ataque nucleófilo de diferentes reactivos sobre iminas coordinadas a paladio. En la primera parte del se observa la reactividad de complejos de paladio(II) con ligandos imina frente a NaBH4. Observándose la formación de especies amiduro y especies amina coordinadas al metal. No obstante, la formación de paladio metálico (por reducción con borohidruro de sodio) es importante en muchos de los casos.. En la segunda parte de este trabajo se examina la reactividad de iminas coordinadas a paladio frente a ataques nucleofílicos con acetona, acetilacetonato y dimetilacetilacetonato, intentando evitar la naturaleza reductora del anterior nucleófilo. En una tercera parte se estudia la reactividad de complejos imina [Pd(acac)(NN’)][BF4] en CH3NO2 y MeLi. También se observa el ataque nucleófilico sobre la imina con formación de enlaces C-C

The role of the periplasmic chaperones SurA, Skp and DegP in fitness, outer membrane integrity, antibiotic susceptibility and virulence of Acinetobacter baumannii: same-same, but different?

The number of nosocomial infections with multidrug-resistant (MDR) strains of Acinetobacter baumannii (Ab) rises worldwide. Hence, MDR Ab became the leading pathogen for which the development of novel antibiotics is of utmost importance. The extreme antibiotic resistance of Ab is especially provided by the composition of its outer membrane (OM). Tightly regulated and specific outer membrane proteins (OMPs) contribute to the efficient barrier function as well as the virulence of Ab. Upon biogenesis, nascent OMPs are guided through the periplasm to the β-barrel assembly machinery (BAM) by periplasmic chaperones. The BAM finally enables insertion of OMPs into the OM. In most Gram-negative bacteria SurA, Skp and DegP represent the major periplasmic chaperones. In Escherichia coli (Ec), Yersinia enterocolitica (Ye) as well as Pseudomonas aeruginosa (Pa) a reduced OM integrity, as well as an increased susceptibility against antibiotics could be observed upon the deletion of SurA. Therefore, the aim of this work was to determine the relevance of SurA and the two other periplasmic chaperones, Skp and DegP in Ab. Markerless single gene knockout mutants for surA, skp and degP were created in AB5075, a highly virulent MDR Ab strain, and analyzed with regards to consequences on OM integrity, antibiotic susceptibility and virulence. In contrast to what has been observed for other Gram-negative pathogens, in Ab only weak phenotypes resulted. Also, the concurrent lack of surA + skp, surA + degP, and skp + degP, which is lethal in Ec, was tolerated well by AB5075. Most surprisingly, even a triple knockout strain, lacking all three periplasmic chaperones was viable. A mass spectrometric analysis revealed no significant reduction in the abundance of the major OMPs of Ab including OmpA and CarO. Thus, our findings suggest the existence of mechanisms that allow Ab to tolerate or compensate for the concurrent lack of the three periplasmic chaperones SurA, Skp and DegP

J004457+4123 (Sharov 21): not a remarkable nova in M31 but a background quasar with a spectacular UV flare

We announce the discovery of a quasar behind the disk of M31, which was previously classified as a remarkable nova in our neighbour galaxy. The paper is primarily aimed at the outburst of J004457+4123 (Sharov 21), with the first part focussed on the optical spectroscopy and the improvement in the photometric database. Both the optical spectrum and the broad band spectral energy distribution of Sharov 21 are shown to be very similar to that of normal, radio-quiet type 1 quasars. We present photometric data covering more than a century and resulting in a long-term light curve that is densely sampled over the past five decades. The variability of the quasar is characterized by a ground state with typical fluctuation amplitudes of ~0.2 mag around B~20.5, superimposed by a singular flare of ~2 yr duration (observer frame) with the maximum at 1992.81 where the UV flux has increased by a factor of ~20. The total energy in the flare is at least three orders of magnitudes higher than the radiated energy of the most luminous supernovae, provided that it comes from an intrinsic process and the energy is radiated isotropically. The profile of the flare light curve appears to be in agreement with the standard predictions for a stellar tidal disruption event where a ~10 M_sun giant star was shredded in the tidal field of a ~2...5 10^8 M_sun black hole. The short fallback time derived from the light curve requires an ultra-close encounter where the pericentre of the stellar orbit is deep within the tidal disruption radius. Gravitational microlensing provides an alternative explanation, though the probability of such a high amplification event is very low.Comment: Accepted for publication in Astronomy and Astrophysics, 14 pages, 11 figure