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  • 1
    Article
    Article
    2008
    ISSN: 0027-8424 
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 25 March 2008, Vol.105(12), pp.4541-6
    Description: The origin of plant chemical ecology generally dates to the late 1950s, when evolutionary entomologists recognized the essential role of plant secondary metabolites in plant-insect interactions and suggested that plant chemical diversity evolved under the selection pressure of herbivory. However, similar ideas had already flourished for a short period during the second half of the 19th century but were largely forgotten by the turn of the century. This article presents the observations and studies of three protagonists of chemical ecology: Anton Kerner von Marilaun (1831-1898, Innsbruck, Austria, and Vienna, Austria), who mainly studied the impact of geological, climatic, and biotic factors on plant distribution and survival; Léo Errera (1858-1906, Brussels, Belgium), a plant physiologist who analyzed the localization of alkaloids in plant cells and tissues histochemically; and Ernst Stahl (1848-1919, Jena, Germany), likely the first experimental ecologist and who performed feeding studies...
    Subject(s): Biochemistry -- History ; Ecology -- History
    ISSN: 0027-8424
    E-ISSN: 1091-6490
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  • 2
    Language: English
    In: NeuroImage, March 2012, Vol.60(1), pp.170-178
    Description: Increasing evidence underlines the functional importance of non-phase-locked cortical oscillatory rhythms. Among the different oscillations, alpha (8–12Hz) has been shown to be modulated by anticipation or attention, suggesting a top-down influence. However, most studies to date have been conducted in the visual modality and the extent to which this notion also applies to the auditory cortex is unclear. It is furthermore often difficult to dissociate bottom-up from top-down contributions in cases of different stimuli (e.g., standards vs. deviants) or stimuli that are preceded by different cues. This study addresses these issues by investigating neuronal responses associated with intrinsically fluctuating perceptions of an invariant sound. Sixteen participants performed a pseudo-frequency-discrimination task in which a “high-pitch” tone was followed by an aversive noise, while the “low-pitch” tone was followed by silence. The participants had to decide which tone was presented...
    Subject(s): Auditory Alpha ; Tau Rhythm ; Auditory Cortex ; Expectancy ; EEG ; Auditory Alpha ; Tau Rhythm ; Auditory Cortex ; Expectancy ; EEG ; Medicine
    ISSN: 1053-8119
    E-ISSN: 1095-9572
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  • 3
    Article
    Article
    2012
    ISSN: 1473-0952 
    Language: English
    In: Planning Theory, August 2012, Vol.11(3), pp.242-256
    Description: In 1973, Horst W Rittel and Malvin A Webber introduced the term ‘wicked problem’ in planning theory. They describe spatial planning as dealing with inherent uncertainty, complexity and inevitable normativity. This contribution picks up the concept of wicked problems, reflects on it from a planning-theoretical perspective, and proposes the use of Cultural Theory’s concept of clumsy solutions as a response to wicked planning problems. In discussing public participation processes in spatial planning, it is then shown what clumsy solutions mean for spatial planning. The four rationalities of Cultural Theory are then used to explain why public participation in planning can become wicked, and how these rationalities provide a response that copes with this wickedness.
    Subject(s): Polyrationality ; Participation ; Expectation Management ; Uncertainty ; Complexity ; Sociology & Social History
    ISSN: 1473-0952
    E-ISSN: 1741-3052
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  • 4
    Language: English
    In: Journal of The Electrochemical Society, 2011, Vol.158(3), p.E32
    Description: The reduction and electrodeposition of TcO{sub 4}{sup -} on a smooth gold foil electrode with an exposed area of 0.25 cm{sup 2} was performed in 1 M H{sub 2}SO{sub 4} supporting electrolyte using bulk electrolysis with a constant current density of 1.0 A/cm{sup 2} at a potential of -2.0 V. Significant hydrogen evolution accompanied the formation of Tc deposits. Tc concentrations consisted of 0.01 M and 2 x 10{sup -3} M and were electrodeposited over various times. Deposited fractions of Tc were characterized by powder x-ray diffraction, x-ray absorption fine structure spectroscopy, and scanning electron microscopy with the capability to measure semiquantitative elemental compositions by energy-dispersive x-ray emission spectroscopy. Results indicate the presence of Tc metal on all samples as the primary electrodeposited constituent for all deposition times and Tc concentrations. Thin films of Tc have been observed followed by the formation of beads that are removable by scratching. After 2000, the quantity of Tc removed from solution and deposited was 0.64 mg Tc per cm{sup 2}. The solution, after electrodeposition, showed characteristic absorbances near 500 nm corresponding to hydrolyzed Tc(IV) produced during deposition of Tc metal. No detectable Tc(IV) was deposited to the cathode.
    Subject(s): 08 Hydrogen ; Absorption ; Current Density ; Deposition ; Electrodeposition ; Electrodes ; Electrolysis ; Electrolytes ; Emission Spectroscopy ; Fine Structure ; Gold ; Hydrogen ; Scanning Electron Microscopy ; Spectroscopy ; Technetium ; Thin Films ; X-Ray Diffraction ; Engineering ; Chemistry;
    ISSN: 00134651
    E-ISSN: 19457111
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  • 5
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 04 March 2014, Vol.111(9), pp.3371-6
    Description: Simian virus 40 (SV40) large tumor antigen (LT) triggers oncogenic transformation by inhibition of key tumor suppressor proteins, including p53 and members of the retinoblastoma family. In addition, SV40 transformation requires binding of LT to Cullin 7 (CUL7), a core component of Cullin-RING E3 ubiquitin ligase 7 (CRL7). However, the pathomechanistic effects of LT-CUL7 interaction are mostly unknown. Here we report both in vitro and in vivo experimental evidence that SV40 LT suppresses the ubiquitin ligase function of CRL7. We show that SV40 LT, but not a CUL7 binding-deficient mutant (LT(Δ69-83)), impaired 26S proteasome-dependent proteolysis of the CRL7 target protein insulin receptor substrate 1 (IRS1), a component of the insulin and insulin-like growth factor 1 signaling pathway. SV40 LT expression resulted in the accumulation and prolonged half-life of IRS1. In vitro, purified SV40 LT reduced CRL7-dependent IRS1 ubiquitination in a concentration-dependent manner. Expression of SV40...
    Subject(s): Antigens, Viral, Tumor -- Metabolism ; Cullin Proteins -- Antagonists & Inhibitors ; Insulin Receptor Substrate Proteins -- Metabolism ; Signal Transduction -- Physiology ; Simian Virus 40 -- Chemistry
    ISSN: 0027-8424
    E-ISSN: 1091-6490
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  • 6
    Language: German
    In: Raumforschung und Raumordnung, 2011, Vol.69(4), pp.257-268
    Description: In den Jahren 1996, 2005 und zuletzt 2010 traten wichtige Änderungen des Wasserhaushaltsgesetzes in Kraft. Diese hatten jeweils zum Ziel, das wasserwirtschaftliche Planungsinstrumentarium zu stärken, um den Flüssen mehr Raum zu geben. Doch wie wirken diese rechtlichen Änderungen in der Praxis? Der vorliegende Beitrag untersucht dies mit Hilfe einer Politikfeldanalyse am Beispiel der Hochwasserkonzeption des Landes Sachsen-Anhalt. Diese Konzeption wurde erstmals 2003 mit dem Zielhorizont 2010 aufgestellt. Zwei Zeiträume werden betrachtet: vor und nach dem Inkrafttreten des Hochwasserschutzgesetzes 2005. Es wird gezeigt, dass die rechtlichen Änderungen nicht auf die Umsetzungsrestriktionen der Praxis antworten. Die Schwierigkeiten in der Praxis bestehen in erster Linie in den Bereichen, in denen andere Akteure als die Wasserwirtschaft – also etwa die Raumordnung, die Bauleitplanung oder Bodeneigentümer – eine wichtige Rolle bei der Umsetzung der wasserwirtschaftlichen Ziele einnehmen. Der Gesetzgeber folgt bei der Realisierung des räumlichen Hochwasserschutzes (Raum für die Flüsse) einem Kontrollparadigma: Es wird stets versucht, die Instrumente der Wasserwirtschaft zu stärken. Die tatsächlichen Praxisprobleme erfordern jedoch Instrumente, die integrative Planungsprozesse ermöglichen, um Konflikte mit räumlichem Hochwasserschutz zu begegnen und auf ein Umdenken in der Wasserwirtschaft hinzuwirken – von einer kontrollierenden zu einer integrativen Form von Governance . Integrativ bedeutet hier die frühzeitige und aktive Einbindung relevanter Stakeholder in die Planungsprozesse. In 1996, 2005, and most recently in 2010 the German Federal Water Act was revised. These revisions aimed at stronger instruments to give more space to the rivers. What is their impact in practice? This paper is going to answer this question with the help of a policy analysis along the flood protection concept of the Land Saxony-Anhalt. For the first time, this concept was prepared in 2003, with a planning horizon until 2010. In the analysis, two periods are regarded: before and after the Federal Flood Control Act 2005. It is shown in this article that the law has not responded to the restrictions for implementation in practice. The restrictions, namely, are in a realm where other stakeholders than water management—for example regional planning, local land use planning or landowners—play a key role in the implementation of aims of water management. In the process of spatial flood protection measures, the German legislator pursues a control paradigm: this means that there is a trend to strengthen the instruments of water management in each reform of the law. In fact, however, instruments are needed which would enable integrative planning processes in order to cope with conflicts in spatial flood protection, and in order to support a rethinking in water management—from a technocratic and controlling towards an integrating mode of governance. Integrative means an early and active enrolment of relevant stakeholders in planning processes.
    Subject(s): Flood protection ; Water management ; German Federal Water Act ; Planning law ; Implementation
    ISSN: 0034-0111
    E-ISSN: 1869-4179
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  • 7
    In: Cerebral Cortex, 2014, Vol. 24(5), pp.1278-1288
    Description: We investigated the sound-induced flash illusion, an example for the influence of auditory information on visual perception. It consists of the perception of 2 visual stimuli upon the presentation of a single visual stimulus alongside 2 auditory stimuli. We used magnetoencephalography to assess the influence of prestimulus oscillatory activity on varying the perception of invariant stimuli. We compared cortical activity from trials in which subjects perceived an illusion with trials in which subjects did not perceive the illusion, keeping the stimulation fixed. Subjects perceived the illusion in approximately 50% of trials. Prior to the illusion, we found stronger beta-band power in left temporal sensors, localized to the left middle temporal gyrus. Illusory perceptions were preceded by increased beta-band phase synchrony between the left middle temporal gyrus and auditory areas as well as by decreased phase synchrony with visual areas. Alpha-band phase synchrony between visual and temporal, parietal, and frontal cortical areas as well as alpha-band phase synchrony between auditory and visual areas were modulated. This supports and extends reports on the influence of brain states prior to stimulation on subsequent perception. We suggest that prestimulus local and network activities form predispositions if sensory streams will be integrated.
    Subject(s): Audiovisual Illusion ; Connectivity ; Magnetoencephalography ; Oscillatory Activity ; Perception
    ISSN: 1047-3211
    E-ISSN: 1460-2199
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  • 8
    In: Physical Chemistry Chemical Physics, 2011, Vol.13(30), pp.13730-13737
    Description: The hydrothermal crystallizations of two zeolite topologies (FAU and LTA) have been studied by simultaneous UV-Raman spectroscopy and X-ray diffraction in a home built setup. A wide angle X-ray diffractometer has been redesigned and combined with Raman components. The results revealed, despite similar structures of the starting gels, different aluminosilicate species evolved in the two systems, prior to emerging Bragg scattering. Based on this the sodalite cage could be ruled out as a common building unit for both frameworks.
    Subject(s): Chemistry;
    ISSN: 1463-9076
    E-ISSN: 1463-9084
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  • 9
    Article
    Article
    2013
    ISSN: 1868-1743 
    Language: English
    In: Molecular Informatics, January 2013, Vol.32(1), pp.9-9
    Subject(s): Pharmacy, Therapeutics, & Pharmacology;
    ISSN: 1868-1743
    E-ISSN: 1868-1751
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  • 10
    In: Psychophysiology, November 2016, Vol.53(11), pp.1651-1659
    Description: Unexpected novel sounds capture one's attention, even when irrelevant to the task pursued (e.g., playing video game). This often comes at a cost to the task (e.g., slower responding). The neural basis for this behavioral distraction effect is not well understood and is subject of this study. Our approach was motivated by findings from cuing paradigms suggesting a link between modulations in oscillatory activity and voluntary attention shifts. The current study tested whether oscillatory activity is also modulated by a task‐irrelevant auditory distractor, reflecting a neural signature of an involuntary shift of attention and accounting for the impaired task performance. We reanalyzed magnetoencephalographic data collected via an auditory‐visual distraction paradigm in which a task‐relevant visual stimulus was preceded by a task‐irrelevant sound on each trial. In 87.5% this was a regular sound (Standard); in 12.5% this was a novel sound (Distractor). We compared nonphase locked oscillatory activity in a time window prior to the visual target as a function of the experimental manipulation (Distractor, Standard). We found low power in the pretarget time window for Distractors compared to Standards in the alpha and beta frequency bands. Importantly, individual alpha power correlated with response speed on a trial‐by‐trial basis for the Distractor only. Sources were localized to the occipital cortex, and also to the parietal and supratemporal cortices. These findings support our hypothesis that the distractor‐related alpha power modulation indexes an involuntary shift of attention which accounts for the impaired task performance.
    Subject(s): Cross‐Modal Distraction ; Involuntary Attention ; Magnetoencephalography Meg ; Alpha Oscillations
    ISSN: 0048-5772
    E-ISSN: 1469-8986
    E-ISSN: 15405958
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