The first male of the extinct bee tribe Melikertini (Hymenoptera: Apidae)

This is the publisher's version, also available electronically from https://journals.ku.edu/index.php/melittology/article/view/4698.The first male bee of the extinct corbiculate tribe Melikertini Engel (Apinae) is described and figured. Mochlomelikertes hoffeinsorum Engel, Breitkreuz, & Ohl, new genus and species, is easily distinguished from other groups within the tribe based on unique male modifications as well as a distinctive forewing venation. Some melikertines are famous for their peculiar modifications and processes, specifically the uniquely enlarged clypeal protrusions found in the genus Succinapis Engel. Mochlomelikertes hoffeinsorum has its own singularly bizarre modifications, particularly an elongate, narrow extension of the mesoscutellum which projects posteriorly over the metanotum, propodeum, and part of the metasoma. The significance of these structures is briefly discussed

Treatments To Produce Stabilized Aluminum Mirrors for Cryogenic Uses

Five metallurgical treatments have been tested as means of stabilizing mirrors that are made of aluminum alloy 6061 and are intended for use in cryogenic applications. Aluminum alloy 6061 is favored as a mirror material by many scientists and engineers. Like other alloys, it shrinks upon cool-down from room temperature to cryogenic temperature. This shrinkage degrades the optical quality of the mirror surfaces. Hence, the metallurgical treatments were tested to determine which one could be most effective in minimizing the adverse optical effects of cooldown to cryogenic temperatures. Each of the five metallurgical treatments comprises a multistep process, the steps of which are interspersed with the steps of the mirror-fabrication process. The five metallurgical-treatment/fabrication.- process combinations were compared with each other and with a benchmark fabrication process, in which a mirror is made from an alloy blank by (1) symmetrical rough machining, (2) finish machining to within 0.006 in. (. 0.15 mm) of final dimensions, and finally (3) diamond turning to a mirror finish

Phylogeny of "Sphecidae" (Hymenoptera: Apoidea) based on molecular data

Die Grabwespen (Sphecidae sensu Bohart & Menke 1976; Sphecidae sensu lato in neueren, phylogenetischen Arbeiten), zu denen nach Day (1984) und späteren Autoren auch die Heterogynaidae zählen, umfassen derzeit 266 Gattungen mit 9559 beschriebene Arten (Pulawski 2006). Zusammen mit den Bienen (= Apiformes nach Michener 2000, bzw. Anthophila nach Engel 2005) bilden die Grabwespen ein gut begründetes Monophylum, das nach Michener (1986) den Namen Apoidea trägt und eine der drei Hauptlinien innerhalb der aculeaten Hymenoptera ist. Die Monophylie der aculeaten Hymenoptera, der Apoidea sowie die der Bienen ist jeweils gut begründet (z.B. Brothers 1975, Königsmann 1978, Lomholdt 1982, Alexander 1992, Brothers & Carpenter 1993). Anders verhält es sich mit den Grabwespen. Neben der phylogenetischen Untersuchung von Brothers & (1993), die die Monophylie der Grabwespen unterstützt, haben andere morphologische als auch molekularsystematische Analysen starken Zweifel an dieser Hypothese aufkommen lassen (z.B. Königsmann 1978, Lomholdt 1982, Alexander 1992, Prentice 1998, Melo 1999, Ohl & Bleidorn 2006).Sequences from the nuclear long-wavelength-rhodopsin and the mitochondrial cytochrom-c-oxidase (subunit I) from different representatives of the Apoidea, with special emphasis on digger wasps (Sphecidae sensu lat), were analysed using maximum parsimony, maximum likelihood and Baysian inference methods. Compared with previous phylogenetic studies based on morphology, the results of the molecular analyses are controversial but correspond in the absence of support for the Sphecidae s. l (sensu Bohart & Menke). The relationships within the Sphecidae sensu stricto correspond largely with recent morphological studies. There is circumstantial evidence that the Ampulicidae and Sphecidae s. str. together form a monophyletic group, whereas the relationships within this taxon are still uncertain. Although there is no evidence for a definitive phylogenetic position of the Heterogynaidae; it can be excluded that they are the sistertaxon to all other Apoidea. Instead, they are probably a derived group within the Crabronidae. In conflict to the majority of current morphological studies, the molecular analyses provide no support for the Crabronidae and Bembicinae. Some molecular analyses imply a close relationship between Philanthinae and bees

What are effective therapies for Clostridium difficile- associated diarrhea?

Oral metronidazole and oral vancomycin are equally effective treatments for Clostridium difficile- associated diarrhea (CDAD) (strength of recommendation [SOR]: A, based on randomized trials). Oral vancomycin is considerably more expensive and may select for colonization with vancomycin-resistant enterococci, leading the American College of Gastroenterology to recommend oral metronidazole as preferred therapy (SOR: C, expert opinion). They recommend therapy with vancomycin for those who are pregnant, breast feeding, less than 10years old, nonresponders to metronidazole, critically ill, or allergic or intolerant to metronidazole (SOR: C, expert opinion)

Dynamics of the extended and intermediate range order in model polymer electrolyte poly(ethylene oxide) and lithium bis(trifluoromethanesulfonyl)imide

The dynamics of lithium ions and polymer chains were investigated at the molecular scale in the model polymer electrolyte Poly (ethylene oxide) (PEO)/Lithium bis(trifluoromethanesulfonyl)imide as a function of temperature. This system is known to present an intermediate range order from the arrangement of neighboring chain segments as well as an extended range order of cylindrically arranged chains. The collective dynamics of the systems at lengthscales matching these structural features was measured using Neutron Spin Echo spectroscopy, gaining insights into their lifetime. Moreover, using isotope substitution techniques the dynamics of the lithium ions with respect to the other atoms was probed. The obtained results are compared with the conductivity and the lithium self-diffusion coefficient measured by NMR to gain experimental insight on the molecular processes triggering lithium transport

Characteristic length scales of the secondary relaxations in glass-forming glycerol

We investigate the secondary relaxations and their link to the main structural relaxation in glass-forming liquids using glycerol as a model system. We analyze the incoherent neutron scattering signal dependence on the scattering momentum transfer, Q , in order to obtain the characteristic length scale for different secondary relaxations. Such a capability of neutron scattering makes it somewhat unique and highly complementary to the traditional techniques of glass physics, such as light scattering and broadband dielectric spectroscopy, which provide information on the time scale, but not the length scales, of relaxation processes. The choice of suitable neutron scattering techniques depends on the time scale of the relaxation of interest. We use neutron backscattering to identify the characteristic length scale of 0.7 Å for the faster secondary relaxation described in the framework of the mode-coupling theory (MCT). Neutron spin-echo is employed to probe the slower secondary relaxation of the excess wing type at a low temperature ( ∼ 1.13Tg . The characteristic length scale for this excess wing dynamics is approximately 4.7 Å. Besides the Q -dependence, the direct coupling of neutron scattering signal to density fluctuation makes this technique indispensable for measuring the length scale of the microscopic relaxation dynamics

Visual short‐term memory‐related EEG components in a virtual reality setup

Virtual reality (VR) offers a powerful tool for investigating cognitive processes, as it allows researchers to gauge behaviors and mental states in complex, yet highly controlled, scenarios. The use of VR head-mounted displays in combination with physiological measures such as EEG presents new challenges and raises the question whether established findings also generalize to a VR setup. Here, we used a VR headset to assess the spatial constraints underlying two well-established EEG correlates of visual short-term memory: the amplitude of the contralateral delay activity (CDA) and the lateralization of induced alpha power during memory retention. We tested observers' visual memory in a change detection task with bilateral stimulus arrays of either two or four items while varying the horizontal eccentricity of the memory arrays (4, 9, or 14 degrees of visual angle). The CDA amplitude differed between high and low memory load at the two smaller eccentricities, but not at the largest eccentricity. Neither memory load nor eccentricity significantly influenced the observed alpha lateralization. We further fitted time-resolved spatial filters to decode memory load from the event-related potential as well as from its time-frequency decomposition. Classification performance during the retention interval was above-chance level for both approaches and did not vary significantly across eccentricities. We conclude that commercial VR hardware can be utilized to study the CDA and lateralized alpha power, and we provide caveats for future studies targeting these EEG markers of visual memory in a VR setup.Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347Cooperation between the Max Planck Society and the Fraunhofer GesellschaftDeutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Peer Reviewe