Humboldt University of Berlin

About: Humboldt University of Berlin is a education organization based out in Berlin, Germany. It is known for research contribution in the topics: Population & Medicine. The organization has 33671 authors who have published 61781 publications receiving 1908102 citations. The organization is also known as: Humboldt-Universität zu Berlin & Universitas Humboldtiana Berolinensis.

Migraine and Ménière's disease: Is there a link?

Abstract: Background: A possible link between Meniere’s disease (MD) and migraine was originally suggested by Prosper Meniere. Subsequent studies of the prevalence of migraine in MD produced conflicting results. Objective: To determine the lifetime prevalence of migraine in patients with MD compared to sex- and age-matched controls. Methods: The authors studied 78 patients (40 women, 38 men; age range 29 to 81 years) with idiopathic unilateral or bilateral MD according to the criteria of the American Academy of Otolaryngology. Diagnosis of migraine with and without aura was made via telephone interviews according to the criteria of the International Headache Society. Additional information was obtained concerning the concurrence of vertigo and migrainous symptoms during Meniere attacks. The authors interviewed sex- and age-matched orthopedic patients (n = 78) as controls. Results: The lifetime prevalence of migraine with and without aura was higher in the MD group (56%) compared to controls (25%; p Conclusions: The lifetime prevalence of migraine is increased in patients with MD when strict diagnostic criteria for both conditions are applied. The frequent occurrence of migrainous symptoms during Meniere attacks suggests a pathophysiologic link between the two diseases. Alternatively, because migraine itself is a frequent cause of audio-vestibular symptoms, current diagnostic criteria may not differentiate between MD and migrainous vertigo.

Impact of Environmental Factors on Product Quality of Greenhouse Vegetables for Fresh Consumption

Abstract: Consumer interest worldwide in the quality of vegetable products has increased in recent years. Product quality is a complex issue. As well as visual characteristics, properties such as texture, the content of minerals and vitamins, flavor and other organoleptic characteristics must be considered. In addition, new knowledge shows that vegetables are appreciated for their beneficial health effects in humans and underlines the importance of nutraceutic properties. Many research studies have documented methods for achieving a high-quality vegetable product. Indoor production for fresh vegetables offers advantages compared to outdoor production with regard to quality assurance principally, because the products are not exposed directly to the rapid changes of climate conditions. On the other hand, vegetable cultivation in a greenhouse under artificially created conditions also affects the internal quality of the product. This is reflected in a different taste and flavor compared with field vegetables. Changes ...

A detailed spectral and morphological study of the gamma-ray supernova remnant RX J1713.7-3946 with HESS

Abstract: We present results from deep observations of the Galactic shell-type supernova remnant (SNR) RX J1713.7-3946 (also known as G347.3-0.5) conducted with the complete H.E.S.S. array in 2004. Detailed morphological and spatially resolved spectral studies reveal the very-high-energy (VHE -- Energies E > 100 GeV) gamma-ray aspects of this object with unprecedented precision. Since this is the first in-depth analysis of an extended VHE gamma-ray source, we present a thorough discussion of our methodology and investigations of possible sources of systematic errors. Gamma rays are detected throughout the whole SNR. The emission is found to resemble a shell structure with increased fluxes from the western and northwestern parts. The differential gamma-ray spectrum of the whole SNR is measured over more than two orders of magnitude, from 190 GeV to 40 TeV, and is rather hard with indications for a deviation from a pure power law at high energies. Spectra have also been determined for spatially separated regions of RX J1713.7-3946. The flux values vary by more than a factor of two, but no significant change in spectral shape is found. There is a striking correlation between the X-ray and the gamma-ray image. Radial profiles in both wavelength regimes reveal the same shape almost everywhere in the region of the SNR. The VHE gamma-ray emission of RX J1713.7-3946 is phenomenologically discussed for two scenarios, one where the gamma rays are produced by VHE electrons via Inverse Compton scattering and one where the gamma rays are due to neutral pion decay from proton-proton interactions. In conjunction with multi-wavelength considerations, the latter case is favoured. However, no decisive conclusions can yet be drawn regarding the parent particle population dominantly responsible for the gamma-ray emission from RX J1713.7-3946.

Pixel-Based Image Compositing for Large-Area Dense Time Series Applications and Science

Abstract: Free and open access to the more than 40 years of data captured in the Landsat archive, combined with improvements in standardized image products and increasing computer processing and storage capabilities, have enabled the production of large-area, cloud-free, surface reflectance pixel-based image composites. Best-available-pixel (BAP) composites represent a new paradigm in remote sensing that is no longer reliant on scene-based analysis. A time series of these BAP image composites affords novel opportunities to generate information products characterizing land cover, land cover change, and forest structural attributes in a manner that is dynamic, transparent, systematic, repeatable, and spatially exhaustive. Herein, we articulate the information needs associated with forest ecosystem science and monitoring in a Canadian context, and indicate how these new image compositing approaches and subsequent derived products can enable us to address these needs. We highlight some of the issues and opportu...

Electrospun Nanomaterials for Supercapacitor Electrodes: Designed Architectures and Electrochemical Performance

Abstract: Electrospinning is the most facile and highly versatile approach to produce 1D polymeric, inorganic, and hybrid nanomaterials with a small diameter, controllable dimensions, and designed architectures In particular, with large surface area, high porosity, low density, good directionality, and tunable composition, electrospun nanofibers and mats are regarded as ideal candidates for various kinds of electrochemical energy storage devices such as supercapacitors (SCs) In this review, the recent progress in electrospun electrode materials for SCs is presented, covering the architecture design and their electrochemical performance After a brief introduction about SCs, the basic principles of the electrospinning technique are discussed Following, attention is paid to the discussion of various electrospun nanofibers and mats including 1D carbons, metal oxides, metal sulfides, metal nitrides, conducting polymers and composite nanomaterials with various types of architectures as electrodes for SCs The relationship between the composition, architecture, and the electrochemical performance is discussed in detail Finally, some challenges and perspectives of future research of the electrospun nanofibers and mats for high performance SCs are highlighted It is anticipated that this review would provide the researchers some inspiration for constructing new types of energy storage devices