8,570 research outputs found
CO2-eq-emissions of organic and conventional foodstuffs in Austria
To date 74 products (in each case KONV, Bio-ZZU and, in part Bio-EU) have been evaluated: dairy products (47 products), fruit and vegetables (currently 15 products), bread products (currently 12 products). This summary only presents the results of selected products in the KONV and Bio-ZZU categories
Percolation, renormalization, and quantum computing with non-deterministic gates
We apply a notion of static renormalization to the preparation of entangled
states for quantum computing, exploiting ideas from percolation theory. Such a
strategy yields a novel way to cope with the randomness of non-deterministic
quantum gates. This is most relevant in the context of optical architectures,
where probabilistic gates are common, and cold atoms in optical lattices, where
hole defects occur. We demonstrate how to efficiently construct cluster states
without the need for rerouting, thereby avoiding a massive amount of
conditional dynamics; we furthermore show that except for a single layer of
gates during the preparation, all subsequent operations can be shifted to the
final adapted single qubit measurements. Remarkably, cluster state preparation
is achieved using essentially the same scaling in resources as if deterministic
gates were available.Comment: 5 pages, 4 figures, discussion of strategies to deal with further
imperfections extended, references update
The multifocal pattern electroretinogram in chloroquine retinopathy
Purpose: Optimal screening for ocular toxicity caused by chloroquine and hydroxychloroquine is still controversial. With the multifocal pattern electroretinogram (mfPERG), a new electrophysiological technique has recently become available to detect early changes of ganglion cells. In this study this new technique is applied to a series of 10 patients seen consecutively receiving long-term chloroquine medication. Methods: In 10 patients receiving chloroquine medication, clinical examination, Amsler visual field testing and computerized color vision testing were performed. If toxicity was suspected, automated perimetry was carried out. In addition, in all patients conventional pattern electroretinogram (PERG) and mfPERG testing were performed. Results: On clinical examination 8 patients showed no chloroquine-associated maculopathy, while 2 patients did. Of these 2, only 1 reported abnormalities when viewing the Amsler chart, while automated perimetry showed typical, ring-like paracentral scotomas in both affected patients and color vision was significantly abnormal. In the normal patients, 4 of 8 had a mild color vision disturbance, which correlated to age-related macular changes. The amplitudes of the PERG and the central (approximately 10degrees) responses of the mfPERG were markedly reduced in chloroquine maculopathy, while the latencies were unchanged. The peripheral rings of mfPERG (ranging to 48degrees) were not affected by chloroquine toxicity. Both PERG and mfPERG were less affected by age-related macular changes. Conclusions: The reduction of PERG and central mfPERG responses in chloroquine maculopathy may help with the early detection of toxicity. Copyright (C) 2004 S. Karger AG, Basel
On the Structure of the Observable Algebra of QCD on the Lattice
The structure of the observable algebra of lattice
QCD in the Hamiltonian approach is investigated. As was shown earlier,
is isomorphic to the tensor product of a gluonic
-subalgebra, built from gauge fields and a hadronic subalgebra
constructed from gauge invariant combinations of quark fields. The gluonic
component is isomorphic to a standard CCR algebra over the group manifold
SU(3). The structure of the hadronic part, as presented in terms of a number of
generators and relations, is studied in detail. It is shown that its
irreducible representations are classified by triality. Using this, it is
proved that the hadronic algebra is isomorphic to the commutant of the triality
operator in the enveloping algebra of the Lie super algebra
(factorized by a certain ideal).Comment: 33 page
Further genetic heterogeneity for autosomal dominant human sutural cataracts
A unique sutural cataract was observed in a 4-generation German family to be transmitted as an isolated autosomal, dominant trait. Since mutations in the gamma-crystallin encoding CRYG genes have previously been demonstrated to be the most frequent reason for isolated congenital cataracts, all 4 active CRYG genes have been sequenced. A single base-pair change in the CRYGA gene has been shown, leading to a premature stop codon. This was not observed in 170 control individuals. However, it did not segregate with the disease phenotype. This is the first truncating mutation in an active CRYG gene without a dominant phenotype. As the CRYGA mutation did not explain the cataract, several other candidate loci (CCV, GJA8, CRYBB2, BFSP2, MIP, GJA8, central pouch-like, CRYBA1) were investigated by micro-satellite markers and linkage analysis, but they were excluded based on the combination of haplotype analysis and two-point linkage analysis. The phenotype in this family is due to a mutation in another sutural cataract gene yet to be identified
Peripheral and central mechanisms involved in hormonal control of male and female reproduction
Reproduction involves the integration of hormonal signals acting across multiple systems togenerate a synchronized physiological output. A critical component of reproduction is the luteinizinghormone (LH) surge, which is mediated by estradiol (E2) and neuroprogesterone interacting tostimulate kisspeptin release in the rostral periventricular nucleus of the third ventricle in rats. Recentevidence has shown that both classical and membrane E2 and progesterone signaling is involved inthis pathway. A metabolite of gonadotropin-releasing hormone (GnRH), GnRH-(1-5), has been shownto stimulate GnRH expression, secretion, and has a role in the regulation of lordosis. Additionally,gonadotropin-inhibitory hormone (GnIH) projects to and influences the activity of GnRH neurons inbirds. Stress-induced changes in GnIH have been shown to alter breeding behaviors in birds,demonstrating another molecular control of reproduction. Peripherally, paracrine and autocrineactions within the gonad have been suggested as therapeutic targets for infertility in both males andfemales. Dysfunction of testicular prostaglandin synthesis is a possible cause of idiopathic maleinfertility. Indeed, local production of melatonin and corticotropin-releasing hormone (CRH) couldinfluence spermatogenesis via immune pathways in the gonad. In females, vascular endothelialgrowth factor A (VEGF-A) has been implicated in an angiogenic process that mediates developmentof the corpus luteum and thus fertility via the Notch signaling pathway. Age-induced decreases infertility involve ovarian kisspeptin and its regulation of ovarian sympathetic innervation. Finally,morphological changes in the arcuate nucleus of the hypothalamus influence female sexualreceptivity in rats. The processes mediating these morphological changes have been shown toinvolve rapid effects of E2 controlling synaptogenesis in this hypothalamic nucleus. Together, thisreview highlights new research in these areas, focusing on recent findings in the molecularmechanisms of central and peripheral hormonal control of reproduction.Fil: Rudolph, L. M.. University of California at Los Angeles; Estados UnidosFil: Bentley, G. E.. University of California Berkeley; Estados UnidosFil: Calandra, Ricardo Saul. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Paredes, A. H.. Universidad de Chile; ChileFil: Tesone, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Wu, T. J.. Uniformed Services University; Estados UnidosFil: Micevych, P. E.. University of California at Los Angeles; Estados Unido
Distinct Quantum States Can Be Compatible with a Single State of Reality
Perhaps the quantum state represents information about reality, and not
reality directly. Wave function collapse is then possibly no more mysterious
than a Bayesian update of a probability distribution given new data. We
consider models for quantum systems with measurement outcomes determined by an
underlying physical state of the system but where several quantum states are
consistent with a single underlying state---i.e., probability distributions for
distinct quantum states overlap. Significantly, we demonstrate by example that
additional assumptions are always necessary to rule out such a model.Comment: 5 pages, 2 figure
Discovering Implicational Knowledge in Wikidata
Knowledge graphs have recently become the state-of-the-art tool for
representing the diverse and complex knowledge of the world. Examples include
the proprietary knowledge graphs of companies such as Google, Facebook, IBM, or
Microsoft, but also freely available ones such as YAGO, DBpedia, and Wikidata.
A distinguishing feature of Wikidata is that the knowledge is collaboratively
edited and curated. While this greatly enhances the scope of Wikidata, it also
makes it impossible for a single individual to grasp complex connections
between properties or understand the global impact of edits in the graph. We
apply Formal Concept Analysis to efficiently identify comprehensible
implications that are implicitly present in the data. Although the complex
structure of data modelling in Wikidata is not amenable to a direct approach,
we overcome this limitation by extracting contextual representations of parts
of Wikidata in a systematic fashion. We demonstrate the practical feasibility
of our approach through several experiments and show that the results may lead
to the discovery of interesting implicational knowledge. Besides providing a
method for obtaining large real-world data sets for FCA, we sketch potential
applications in offering semantic assistance for editing and curating Wikidata
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