2-Undecanone : a new attractant for anthropophilic mosquitoes

Stechmücken der Art Stegomyia aegypti (ehemals Aedes aegypti, REINERT et al. 2004) sind die wichtigsten Überträger von Gelbfieber- und Dengueviren. Diverse Arten der Gattung Anopheles verbreiten die Erreger der Malaria. Bei Versuchen, Malaria, Gelbfieber und Dengue einzudämmen, wurden in den letzten Jahrzehnten wiederholt Kampagnen gegen Stechmücken geführt. Dabei wurden Insektizide vielfach flächendeckend ausgebracht. Dies führte kurzfristig zu geringeren Mückendichten, allerdings entwickelten sich auch vielerorts gegen diese Gifte resistente Mückenpopulationen. Anstelle des flächendeckenden Gifteinsatzes wird heute versucht, die Insektizide örtlich und zeitlich effektiv einzusetzen, um so die Gefahr weiterer Resistenzbildung zu minimieren und sowohl die Kosten als auch die Belastung für Umwelt und Bevölkerung möglichst gering zu halten. Um Insektizide zur richtigen Zeit gezielt ausbringen zu können, ist ein Monitoring der Mücken erforderlich. Mückenfallen, die durch optische Effekte und Duftstoffe gezielt anthropophile Stechmückenarten anlocken, sind für ein derartiges Bestandsmonitoring besonders geeignet. Auf der Suche nach attraktiven Duftstoffen, welche die Effektivität solcher Fallen erhöhen, wurde unter anderem auch 2-Undecanon getestet. In Verhaltensversuchen mit den anthropophilen Mückenarten Stegomyia aegypti und Anopheles stephensi konnte die Attraktivität dieser Substanz sowohl als Einzelreiz als auch in Kombination mit anderen Attraktanzien gezeigt und quantifiziert werden.The attractiveness of 2-undecanone to host-seeking female Stegomyia aegpyti (former Aedes aegypti) and female Anopheles stephensi (Diptera: Culicidae) mosquitoes was tested in a Y-tube bioassay under laboratory conditions. -Undecanone alone in a concentration of 40 ppm was significantly more attractive to S. aegypti mosquitoes than pure air. In combination with other kairomones such as caproic acid, lactic acid and ammonia doses of 2-undecanone from 4 ppm up to 130 ppm augmented significantly the attractiveness of these kairomones. The synergism of 2-undecanone with other attractants is comparable to that one described for lactic acid. The combination of 2-undecanone with lactic acid, however, was more attractive than the two compounds as single stimuli. Interestingly 2-undecanone is neither known as an human skin compound nor as a volatile in human breath. First field experiments near Regensburg in Germany with BG-Sentinel® mosquito traps could not confirm the attractive effect of 2-undecanone (ROSE et al. 2006) for Culex species. A possible explanation could be that the tested dose of 2-undecanone was not in the optimum range or that the studied species do not respond to this compound

VLT/X-Shooter Near-Infrared Spectroscopy and HST Imaging of Gravitationally-Lensed z~2 Compact Quiescent Galaxies

Quiescent massive galaxies at z~2 are thought to be the progenitors of present-day massive ellipticals. Observations revealed them to be extraordinarily compact. The determination of stellar ages, star formation rates and dust properties via spectroscopic measurements has up to now only been feasible for the most luminous and massive specimens (~3x M*). Here we present a spectroscopic study of two near-infrared selected galaxies which are close to the characteristic stellar mass M* (~0.9x M* and ~1.3x M*) and whose observed brightness has been boosted by the gravitational lensing effect. We measure the redshifts of the two galaxies to be z=1.71\pm0.02 and z=2.15\pm0.01. By fitting stellar population synthesis models to their spectro-photometric SEDs we determine their ages to be 2.4^{+0.8}_{-0.6} Gyr and 1.7\pm0.3 Gyr, respectively, which implies that the two galaxies have higher mass-to-light ratios than most quiescent z~2 galaxies in other studies. We find no direct evidence for active star-formation or AGN activity in either of the two galaxies, based on the non-detection of emission lines. Based on the derived redshifts and stellar ages we estimate the formation redshifts to be z=4.3^{+3.4}_{-1.2} and z=4.3^{+1.0}_{-0.6}, respectively. We use the increased spatial resolution due to the gravitational lensing to derive constraints on the morphology. Fitting Sersic profiles to the de-lensed images of the two galaxies confirms their compactness, with one of them being spheroid-like, and the other providing the first confirmation of a passive lenticular galaxy at a spectroscopically derived redshift z~2.Comment: accepted for publication in Ap

Qualität in der Kindertageseinrichtung aus Eltern- und Fachkräftesicht. Ergebnisse einer multiperspektivischen Fragebogenstudie. Kurzbericht

In der Fachabteilung „Kinder und Kinderbetreuung“ des Deutschen Jugendinstituts e.V. wurde zwischen Dezember 2016 und Dezember 2018 die Studie „MS-Kita“ (Methodenstudie: Qualität in der Kindertageseinrichtung) durchgeführt, die vom Bundesministerium für Familie, Senioren, Frauen und Jugend (BMFSFJ) gefördert wurde. Die Studie bestand aus zwei Projektbausteinen: der eine befasste sich mit pädagogischer Qualität aus Eltern- und Fachkräftesicht, der andere mit der Erhebung pädagogischer Qualität unter Anwendung standardisierter Beobachtungsinstrumente für den frühpädagogischen Bereich. In der vorliegenden Publikation werden zentrale Projektergebnisse des ersten Bausteins, der Eltern- und Fachkräftebefragung, dargestellt. (DIPF/Orig.

Near-Death-Experiences: Between Spiritual Transmigration and Psychopathological Hallucinations

The research in the field of Near-Death-Experiences (NDE) shows us various reports of the process of dying which contradict the widely shared medical opinions in the past. Based on these observations, Raymond Moody developed and differentiated specific stages in the process of dying. Although these stages cannot be empirically proven, for some of the described stages scientific explanations can be found. For example, NDE have been reported in the terminal phase of life-threatening diseases, which can be explained by neurobiological changes of transmitter substances in dying person's brains. Further explanatory models fall back on other influences, e.g. side effects of sedative medication, psychedelic drugs, meditation, epilepsy, migraine or oneiroid psychosis. The large number of different visual experiences (tunnel vision, encounter with close relatives, bright lights, God, flowering gardens etc.) which appear in the course of a NDE, can be interpreted as visual hallucinations or oneiroid dreams as a consequence of medication or endogenous opioid production; in addition, a genetic predisposition could play an essential role. A NDE possibly is a final protective mechanism of the brain in agonizing patients, which leads to feelings of euphoria and experiences of hallucinations, caused by the explosive release of neurotransmitters. Positive emphasis should be given to the fact that in periods of increasing secularization the investigations of NDE have provided new hope of a life after death in the past 30 years. For many patients, caregivers, physicians and nurses, Moody's book was a great help in overcoming fears of dying and death. In spite of all legitimate criticism, the "nine elements of the Near-Death Experiences", still inspires researchers to have a different look on the process of dying

The high A_V Quasar Survey: A z=2.027 metal-rich damped Lyman-alpha absorber towards a red quasar at z=3.21

To fully exploit the potential of quasars as probes of cosmic chemical evolution and the internal gas dynamics of galaxies it is important to understand the selection effects behind the quasar samples and in particular if the selection criteria exclude foreground galaxies with certain properties (most importantly a high dust content). Here we present spectroscopic follow-up from the 10.4-m GTC telescope of a dust-reddened quasar, eHAQ0111+0641, from the extended High A_V Quasar (HAQ) survey. We find that the z=3.21 quasar has a foreground Damped Lyman-alpha Absorber (DLA) at z=2.027 along the line of sight. The DLA has very strong metal lines due to a moderately high metallicity (with an inferred lower limit of 25% of the solar metallicity), but a very large gas column density along the line-of-sight in its host galaxy. This discovery is further evidence that there is a dust bias affecting the census of metals, caused by the combined effect of dust obscuration and reddening, in existing samples of z>2 DLAs. The case of eHAQ0111+0641 illustrates that dust bias is not only caused by dust obscuration, but also dust reddening.Comment: 7 pages, 4 figures. Accepted for publication in A&A. A few typos have been correcte

Extinction curve template for intrinsically reddened quasars

We analyze the near-infrared to UV data of 16 quasars with redshifts ranging from 0.71 $<$ $z$ $<$ 2.13 to investigate dust extinction properties. The sample presented in this work is obtained from the High $A_V$ Quasar (HAQ) survey. The quasar candidates were selected from the Sloan Digital Sky Survey (SDSS) and the UKIRT Infrared Deep Sky Survey (UKIDSS), and follow-up spectroscopy was carried out at the Nordic Optical Telescope (NOT) and the New Technology Telescope (NTT). To study dust extinction curves intrinsic to the quasars, from the HAQ survey we selected 16 cases where the Small Magellanic Cloud (SMC) law could not provide a good solution to the spectral energy distributions (SEDs). We derived the extinction curves using Fitzpatrick & Massa 1986 (FM) law by comparing the observed SEDs to the combined quasar template from Vanden Berk et al. 2001 and Glikman et al. 2006. The derived extinction, $A_V$, ranges from 0.2-1.0 mag. All the individual extinction curves of our quasars are steeper ($R_V=2.2$-2.7) than that of the SMC, with a weighted mean value of $R_V=2.4$. We derive an `average quasar extinction curve' for our sample by fitting SEDs simultaneously by using the weighted mean values of the FM law parameters and a varying $R_V$. The entire sample is well fit with a single best-fit value of $R_V=2.2\pm0.2$. The `average quasar extinction curve' deviates from the steepest Milky Way and SMC extinction curves at a confidence level $\gtrsim95\%$. Such steep extinction curves suggest a significant population of silicates to produce small dust grains. Moreover, another possibility could be that the large dust grains may have been destroyed by the activity of the nearby active galactic nuclei (AGN), resulting in steep extinction curves.Comment: 8 pages, 4 figures, 1 tabl