A promising biotechnical approach to pest management of the western corn rootworm in Illinois maize fields shielded with a MCA kairomone baited trap line

The leaf beetle Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), (D.v.v.), also called the western corn rootworm, is endemic to the New World and ranks among the top ten insect pests in worldwide grain production. D.v.v. causes annual damages of 1 billion US Dollars and is a notoriously difficult insect pest to control and manage, as entomological history of the past 50 years amply demonstrates (METCALF 1986). Considering recent emphasis on environmentally compatible and sustainable management strategies, entomologists and practitioners are encouraged to pay increased attention to novel approaches such as biotechnial methods which today are characterized by preferential use of signal compounds. Fortunately, both insect and plants provide a wide variety of such natural resources. In the case of D.v.v., sex pheromonesand plant kairomones as specific attractants and management tools are relatively well investigated through numerous contributions by GUSS et al. (1982), METCALF & METCALF (1992), METCALF (1994) and many recent publications on the advance and spread of D.v.v. within Europe (BERGER 1995-2004, HUMMEL 2003). Principle of MSD method: In this paper, the plant kairomone 4-methoxycinnamaldehyde (MCA), a specific attractant for D.v.v., is being used as a tool within the newly proposed "MSD" strategy. It combines a two pronge approach consisting as the well known mass trapping with the novel shielding and deflecting, called in short "diversion" and introduced here for the first time. An invisible “curtain” or “fence” of MCA vapor released from a MCA trap line establishes a behavioral barrier which the flying beetles cannot easily pass without being 1. either caught in one of the high capacity traps or 2. being diverted elsewhere. The net effect is a significant reduction in adult population density and oviposition within the MCA treated field as compared to an untreated control field. These effects can be experimentally measured by 1. adult beetle counts on maize plants, 2. by counts in independent monitoring traps baited with the D.v.v. sex pheromone, and 3. by egg counts taken in soil samples.Umweltgerechter und nachhaltiger Pflanzenschutz erfordert eine Vielzahl verschiedener Strategien zum Management von Schadinsekten auf ihren Wirtspflanzen. Insekten- und pflanzeneigene Signalstoffe sowie ihre synthetischen Analoga bieten einen nahezu unerschöpflichen Vorrat spezifischer Lockwirkungen und Interventionsmöglichkeiten an, der bisher leider nur unzureichend genutzt wird. Kürzliche Entdeckungen sowohl neuer Kairomon-Lockstoffe als auch neuer Verfahrensschritte für das Management des Westlichen Maiswurzelbohrers Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) (D.v.v.) erweitern das Spektrum anwendbarer Management- Optionen für diesen schwer bekämpfbaren Schädling im nordamerikanischen Maisanbau. Seit seiner Einschleppung nach Europa (ČAMPRAG & BAČA 1995) wird D.v.v. neuerdings auch zunehmend zum Problemschädling an Mais in Europa. Die neue "MSD"-Technik besteht aus einer Kombination von Massenabfang ("mass trapping"), Abschirmung ("shielding") und Umlenkung ("diversion") der Blattkäfer. Fallen hoher Fangkapazität, die das Kairomon 4-Methoxyzimtaldehyd (MCA) und Cucurbitacin- Pulver als fraßfördernden Stoff enthalten, können bei Aufstellung als "Fallenzaun" relativ geringer Dichte die Käfer so umlenken, dass zwischen den beiden Seiten dieses Zauns eine unsichtbare Geruchs-Barriere entsteht. Diese führt zu einer messbaren und signifikanten Verminderung der Käferzahl zwischen MCA behandelten Feldabschnitten gegenüber ihren unbehandelten Kontrollen. In 0,27 ha bzw. 0,12 ha großen Maisversuchsfeldern der Standorte Urbana und Champaign des US-Staates Illinois ließen sich während der Monate August und September 2003 und 2004 nach MCA-Behandlung gegenüber Kontrollen deutliche und signifikante Verminderungen von D.v.v. an Hand dreier Kriterien nachweisen: 1. Käferzahlen auf Maispflanzen innerhalb des "MSD-Feldes", 2. Käferzahlen in Sexuallockstoff-Fallen im MSD Feld und 3. die Zahl abgelegter D.v.v.-Eier im Boden des MSD Feldes nehmen ab. Der beobachtete Effekt läßt sich nicht allein auf die Populationsverminderung infolge hoher Abfangzahlen zurückführen. Es gibt darüber hinaus einen Abschirm- und Umlenkeffekt, dessen sinnes- und verhaltensphysiologische Mechanismen zusätzliche künftige Erforschungen erforderlich machen

High Latitude Radio Emission in a Sample of Edge-On Spiral Galaxies

We have mapped 16 edge-on galaxies at 20 cm using the VLA. For 5 galaxies, we could form spectral index, energy and magnetic field maps. We find that all but one galaxy show evidence for non-thermal high latitude radio continuum emission, suggesting that cosmic ray halos are common in star forming galaxies. The high latitude emission is seen over a variety of spatial scales and in discrete and/or smooth features. In general, the discrete features emanate from the disk, but estimates of CR diffusion lengths suggest that diffusion alone is insufficient to transport the particles to the high latitudes seen (> 15 kpc in one case). Thus CRs likely diffuse through low density regions and/or are assisted by other mechanisms (e.g. winds). We searched for correlations between the prevalence of high latitude radio emission and a number of other properties, including the global SFR, supernova input rate per unit star forming, and do not find clear correlations with any of these properties.Comment: 40 pages of text, 3 figures, 6 tables, and an appendix of 21 jpeg figures (which is a radio continuum catalogue of 17 galaxies). to appear in A. J. (around January 1999

Instant Two-Body Equation in Breit Frame

A quasipotential formalism for elastic scattering from relativistic bound states is based on applying an instant constraint to both initial and final states in the Breit frame. This formalism is advantageous for the analysis of electromagnetic interactions because current conservation and four momentum conservation are realized within a three-dimensional formalism. Wave functions are required in a frame where the total momentum is nonzero, which means that the usual partial wave analysis is inapplicable. In this work, the three-dimensional equation is solved numerically, taking into account the relevant symmetries. A dynamical boost of the interaction also is needed for the instant formalism, which in general requires that the boosted interaction be defined as the solution of a four-dimensional equation. For the case of a scalar separable interaction, this equation is solved and the Lorentz invariance of the three-dimensional formulation using the boosted interaction is verified. For more realistic interactions, a simple approximation is used to characterize the boost of the interaction.Comment: 20 pages in revtex 3, 3 figures. Fixed reform/tex errors

Electromagnetic Scattering from Relativistic Bound States

The quasipotential formalism for elastic scattering from relativistic bound states is formulated based on the instant constraint in the Breit frame. The quasipotential electromagnetic current is derived from Mandelstam's five-point kernel and obeys a two-body Ward identity. Breit-frame wave functions are obtained directly by solving integral equations with nonzero total three-momentum, thus accomplishing a dynamical boost. Calculations of electron-deuteron elastic form factors illustrate the importance of the dynamical boost versus kinematic boosts of the rest frame wave functions.Comment: RevTeX 3.0 manuscript, 9 pages. UU-file is a single PostScript file of the manuscript including figures. U. MD PP #93-17

The neem tree Azadirachta indica A.Juss (Meliaceae) and its close relatives are plants of versatile properties with many applications

Ausgangspunkt für den Enthusiasmus von Seiten der Pflanzenschützer und Mediziner für Niem war eine Zufallsbeobachtung von H. Schmutterer, der während seines Aufenthalts im Sudan zwischen 1959 und 1961 einen Heuschreckeneinfall von Schistocerca gregaria erlebte. In dessen Folge war, wie seit biblischen Zeiten (2. Mose, Kapitel 10, Verse 1-20) wohl bekannt, meilenweit kein Grün mehr verblieben, mit Ausnahme einiger Niembäume, an denen die gefräßigen Heuschrecken vorübergezogen waren. Schmutterer ging dieser Beobachtung nach und fand, dass der Baum ein fraßabschreckendes Prinzip enthalten muss, das die Heuschrecken auf Distanz hält. Tatsächlich konnten Butterworth & Morgan 1972 einen niemeigenen Stoff dieser Wirkung dingfest machen. Wir wissen heute als Resultat eines Zusammenwirkens einer Reihe von Forschergruppen in Europa, USA, Indien, China und Japan von der Existenz des Azadirachtins, des kompliziert gebauten Hauptwirkstoffs, dessen chemische Struktur vor 22 Jahren von mehreren Gruppen unabhängig und zweifelsfrei identifiziert wurde. Azadirachtin hat sich in der Folgezeit hartnäckig der Totalsynthese widersetzt (Ley & al. 1993). Lediglich sterile Suspensionskulturen von Azadirachta indica lieferten Azadirachtin und seine Kongeneren sowie die verwandten Limonoide Salannin und Nimbin biosynthetisch, freilich in sehr schlechten Ausbeuten und unter hohen Kosten (Morgan & Allen 2002). Erst kürzlich wurde die erste gelungene Totalsynthese von Veitch & al. (2007) bekannt, die wegen der Komplexität der Struktur eine echte Herausforderung an die Kunst der beteiligten Chemiker darstellte. Angesichts des hohen Preises der synthetischen Wirkstoffe wird der Anwender von Niemprodukten auch künftig nach günstigen natürlichen Quellen des Rohmaterials Ausschau halten, wofür hauptsächlich Samen, aber auch Blätter in Frage kommen. Der Niembaum gedeiht in allen subtropischen und tropischen Ländern der Erde. Eine frosttolerante Variante mit Anwendungspotenzial in gemäßigten Breiten ist aus den Gebirgstälern des Himalaya bekannt. Im Folgenden seien einige jüngere Entwicklungen der Niemforschung und -anwendung skizziert. Der Problematik des organischen Landbaus wird dabei ein eigener kurzer Abschnitt eingeräumt.Their effectiveness in medicine, plant and stored product protection are age old cultural heritage in southeast Asia. Recently this knowledge was confirmed by experiments with modern entomological, chemical and biochemical methodology. Natural products of the neem tree are used in medicine for the treatment of malaria, eczema, lice and mites. Applications also extend to the art of sustainable, environmentally benign plant protection. In the course of the last third of the 20th century Giessen became one of the leading universities of European neem research. Mode of action studies, comparative investigations on feeding inhibition and molting in arthropods, but also numerous field applications directed against agriculturally and medically important pests lured a large number of candidates, graduate students and postdocs to Giessen to receive their training under Prof. Dr. H. Schmutterer. Because of increasing pesticide resistance and a significantly reduced number of pesticide registrations worldwide, natural products of the neem tree are gaining additional importance in the world market. Today, they are valued as prime examples for sustainable, environmentally benign alternatives in crop protection where other approaches are beginning to fail. Particularly critical is the situation in ecological farming where synthetic pesticides and mineral fertilizers are forbidden and where some natural products can fill a significant even if expensive gap. New large scale efforts of afforestation with rapidly growing neem trees in southeast Asia will pretty soon facilitate the worldwide supply with less expensive neem products

Testing Radiatively-Inefficient Accretion Flow Theory: an XMM-Newton Observation of NGC 3998

We present the results of a 10 ks XMM-Newton observation of NGC 3998, a ``type-I'' LINER galaxy. Our goal is to test the extent to which radiatively-inefficient accretion flow (RIAF) models and/or scaled-down AGN models are consistent with the observed properties of NGC 3998. The upper-limit for narrow Fe-K emission derived from a combined fit of the XMM-Newton and BeppoSAX spectra is 25 eV, which is one of the strictest limits to date for any AGN. This significantly rules out Fe-K emission as is expected to be observed in typical Seyfert 1 galaxies. The lack of any reflection features suggests that any optically-thick, geometrically-thin accretion disk must be truncated, probably at a radius of order 100-300 R_s. RIAF models fit the UV to X-ray spectral energy distribution of NGC 3998 reasonably well. In these models the mid-IR flux also constrains the emission from any outer thin disk component that might be present. The UV to X-ray SED is also consistent with a Comptonized thin disk with a very low accretion rate, in which case the lack of Fe-K emission may be due to an ionized accretion disk. Accretion models in general do not account for the observed radio flux of NGC 3998, and the radio flux may be due to a jet. Recent jet models may also be consistent with the nuclear fluxes of NGC 3998 in general, including the X-ray, optical/UV and mid-IR bands. We also derive nuclear fluxes using archival HST WFPC2 data to constrain the SED of NGC 3998. We discuss a possible OM U band and USNO-B detection of the NGC 3998 ULX.Comment: Accepted for publication in ApJ. 13 pages and 5 figures formatted with emulateapj. Version with black-and-white only plots available at http://www.pha.jhu.edu/~ptak/paper

Cicrumnuclear Supernova Remnants and HII Regions in NGC 253

Archival VLA data has been used to produce arcsecond-resolution 6- and 20-cm images of the region surrounding the nuclear 200-pc (~15") starburst in NGC 253. Twenty-two discrete sources stronger than 0.4 mJy have been detected within ~2 kpc (~3') of the galaxy nucleus; almost all these sources must be associated with the galaxy. None of the radio sources coincides with a detected X-ray binary, so they appear to be due to supernova remnants and H II regions. The region outside the central starburst has a derived radio supernova rate of <~0.1/yr, and may account for at least 20% of the recent star formation in NGC 253. Most of the newly identified sources have steep, nonthermal radio spectra, but several relatively strong thermal sources also exist, containing the equivalent of tens of O5 stars. These stars are spread over tens of parsecs, and are embedded in regions having average ionized gas densities of 20-200/cm^3, much lower than in the most active nuclear star-forming regions in NGC 253 or in the super star clusters seen in other galaxies. The strongest region of thermal emission coincides with a highly reddened area seen at near-infrared wavelengths, possibly containing optically obscured H II regions.Comment: 17 pages, 3 postscript figures, AASTeX format, in press for Astronomical Journal, July 200

Interface to high-performance periodic coupled-cluster theory calculations with atom-centered, localized basis functions

Coupled cluster (CC) theory is often considered the gold standard of quantum-chemistry. For solids, however, the available software is scarce. We present CC-aims, which can interface ab initio codes with localized atomic orbitals and the CC for solids (CC4S) code by the group of A. Gr\"uneis. CC4S features a continuously growing selection of wave function-based methods including perturbation and CC theory. The CC-aims interface was developed for the FHI-aims code (https://fhi-aims.org) but is implemented such that other codes may use it as a starting point for corresponding interfaces. As CC4S offers treatment of both molecular and periodic systems, the CC-aims interface is a valuable tool, where DFT is either too inaccurate or too unreliable, in theoretical chemistry and materials science alike

Chandra Observations of NGC 4438: An Environmentally Damaged Galaxy in the Virgo Cluster

We present results from a 25 ksec CHANDRA ACIS-S observation of galaxies NGC4438 and NGC4435 in the Virgo Cluster. X-ray emission in NGC4438 is observed in a ~700 pc nuclear region, a 2.3 kpc spherical bulge, and a network of filaments extending 4-10 kpc to the W and SW of the galaxy. The X-ray emission in all 3 regions is highly correlated to similar features observed in Halpha. Spectra of the filaments and bulge are well represented by a 0.4 keV MEKAL model with combined 0.3-2 keV intrinsic luminosity of 1.24x10^{40}erg/s, electron densities ~ 0.02-0.04 cm^{-3}, cooling times of 400-700 Myr and X-ray gas mass <~ 3.7x10^8 Msolar. In the nuclear region of NGC4438 X-ray emission is seen from the nucleus and from two outflow bubbles extending 360(730) pc to the NW(SE) of the nucleus. The spectrum of the NW outflow bubble plus nucleus is well fitted by an absorbed (n_H=1.9x10^{21} cm^{-2}) 0.58 keV MEKAL plasma model plus a heavily absorbed (n_H = 2.9 x10^{22} cm^{-2}) Gamma = 2, power law component. The electron density, cooling time, and X-ray gas mass in the NW outflow are ~0.5 cm^{-3}, 30 Myr and 3.5x10^6 Msolar. Weak X-ray emission is observed in the central region of NGC4435 with the peak of the hard emission coincident with the galaxy's optical center; while the peak of the soft X-ray emission is displaced 316 pc to the NE. The spectrum of NGC 4435 is well fitted by a non-thermal power law plus a thermal component from 0.2-0.3 keV diffuse ISM gas. We argue that the X-ray properties of gas outside the nuclear region in NGC4438 and in NGC4435 favor a high velocity, off-center collision between these galaxies ~ 100 Myr ago; while the nuclear X-ray emitting outflow gas in NGC4438 has been heated only recently (within ~ 1-2 Myr) by shocks (v_s ~ 600 kms^{-1}) possibly powered by a central AGN.Comment: 40 pages, 7 figures; minor changes to conform to published version, improved spectral fits to NGC 4435, improved figures 3,5; new figures 6b,

Infrared Spectroscopy of a Massive Obscured Star Cluster in the Antennae Galaxies (NGC 4038/4039) with NIRSPEC

We present infrared spectroscopy of the Antennae Galaxies (NGC 4038/4039) with NIRSPEC at the W. M. Keck Observatory. We imaged the star clusters in the vicinity of the southern nucleus (NGC 4039) in 0.39" seeing in K-band using NIRSPEC's slit-viewing camera. The brightest star cluster revealed in the near-IR (M_K(0) = -17.9) is insignificant optically, but coincident with the highest surface brightness peak in the mid-IR (12-18 micron) ISO image presented by Mirabel et al. (1998). We obtained high signal-to-noise 2.03 - 2.45 micron spectra of the nucleus and the obscured star cluster at R ~ 1900. The cluster is very young (4 Myr old), massive (16e6 M_sun), and compact (density ~ 115 M_sun pc^(-3) within a 32 pc half-light radius), assuming a Salpeter IMF (0.1 - 100 M_sun). Its hot stars have a radiation field characterized by T_eff ~ 39,000 K, and they ionize a compact H II region with n_e ~ 1e4 cm^(-3). The stars are deeply embedded in gas and dust (A_V ~ 9-10 mag), and their strong FUV field powers a clumpy photodissociation region with densities n_H >= 1e5 cm^(-3) on scales of up to 200 pc, radiating L[H_2 1-0 S(1)] = 9600 L_sun.Comment: 4 pages, 5 embedded figures. To appear in proceedings of 33d ESLAB Symposium: Star Formation from the Small to the Large Scale, held in Noordwijk, The Netherlands, Nov. 1999. Also available at http://astro.berkeley.edu/~agilber