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91.
Barles S 《The Science of the total environment》2007,375(1-3):48-58
The flows of foodstuffs (and the nitrogen they contain) through the city of Paris in the 19th and early 20th century were evaluated. Between 1801 and 1914, the fivefold increase in the population of Paris, as well as the threefold increase in the number of horses used in urban transport, gave rise to increased needs for food and feed. The corresponding inputs of nitrogen increased from 6000 tN/year in 1817 to 25,000 tN/year from the rural hinterland to the city. The corresponding per capita inflows were relatively stable throughout the period and may be divided into four more or less equal parts (flour, meat, other human foodstuffs, forage), each representing about 6 gN per inhabitant per day. In total, the demand for foodstuffs was of the order of 24 gN per inhabitant per day, one quarter of which was for transport. The fate of this dietary nitrogen after consumption changed a lot with the techniques used for exploiting urban excreta of all kinds, particularly of nitrogen, which was in great demand until the development of synthetic fertilizers. Dietary nitrogen flow diagrams are established for the years 1817, 1869 and 1913, and reveal an increasing improvement of the agricultural reuse (from 20 to 40% of the inflowing N). 相似文献
92.
Geert R. Verheyen Filip Meersman Isabelle Noyens Sarah Goossens Sabine Van Miert 《European Journal of Lipid Science and Technology》2023,125(3):2200193
The depletion of natural resources, the increasing use of valuable land surface for human activities, and the generation of waste are detrimental to the planet. Sustainable alternatives to guarantee a sufficient supply of food, feed, and biomaterials are needed. Insects may hold an interesting position in a circular economy to tackle contemporary societal challenges. Using insects for food, feed, biomaterial production, and to valorize side-streams, have gained increased interest. Mealworms are amenable to large-scale farming. Herein, the potential of mealworm oil for implementation in a cosmetic hand cream is evaluated. It is shown that mealworms are rich in oil (≈30% of the dry weight), and the oil can be extracted using hexane or ethyl acetate as a solvent. The euthanization step of mealworms has profound effect on the free fatty acid content. The fatty acid profile indicates a large proportion of unsaturated fatty acids, which is promising for use in cosmetic applications. In a proof of concept, the mealworm oil is implemented in a hand cream and compared to hand cream containing macadamia nut oil. No differences in odor and aspect/stability are observed, but mealworm creams are slightly less white color. Mealworm oil is suitable for cosmetics applications. Practical applications: Several insect species can be sustainably reared on low-value organic side-streams, requiring only small amounts of land-surface, less water, and producing less greenhouse gases. In addition, they have short life cycles and can be reared continuously and locally. This implies that insects are an interesting source of biological materials including proteins and oils. Insect oils, including oil of mealworms, have interesting fatty acid profiles that make them amenable to replace oils of vegetable origin for applications within cosmetics. The results indicate that mealworm oil can be a novel, sustainable ingredient for use in the cosmetics industry. 相似文献
93.
94.
We have studied omphalopagus conjoined twins with a diamniotic monochorionic placenta. Although conjoined twins usually present in a single amniotic sac, one other example of diamniotic placenta has been reported in omphalopagus twins [Weston et al., 1990: Am J Med Genet 37:558-561]. Most theories concerning the pathogenesis of conjoined twinning exclude the possibility of diamniotic placentation. However, Spencer [1992: Teratology 45:591-602] recently elaborated a model for conjoined twinning based on duplication of organizing centers (primitive streaks) during gastrulation. We have considered the fate of embryonic membranes according to this model of omphalopagus twinning and show that diamniotic placentation is a predictable outcome. 相似文献
95.
Britta Troppmann Sabine Balfanz Christian Krach Arnd Baumann Wolfgang Blenau 《International journal of molecular sciences》2014,15(1):629-653
We have isolated a cDNA coding for a putative invertebrate-type dopamine receptor (Peadop2) from P. americana brain by using a PCR-based strategy. The mRNA is present in samples from brain and salivary glands. We analyzed the distribution of the PeaDOP2 receptor protein with specific affinity-purified polyclonal antibodies. On Western blots, PeaDOP2 was detected in protein samples from brain, subesophageal ganglion, thoracic ganglia, and salivary glands. In immunocytochemical experiments, we detected PeaDOP2 in neurons with their somata being located at the anterior edge of the medulla bilaterally innervating the optic lobes and projecting to the ventro-lateral protocerebrum. In order to determine the functional and pharmacological properties of the cloned receptor, we generated a cell line constitutively expressing PeaDOP2. Activation of PeaDOP2-expressing cells with dopamine induced an increase in intracellular cAMP. In contrast, a C-terminally truncated splice variant of this receptor did not exhibit any functional property by itself. The molecular and pharmacological characterization of the first dopamine receptor from P. americana provides the basis for forthcoming studies focusing on the significance of the dopaminergic system in cockroach behavior and physiology. 相似文献
96.
Sabine Leutheusser-Schnarrenberger 《Datenschutz und Datensicherheit - DuD》2010,34(8):519-522
Nachdem als letzter Mitgliedstaat der Europ?ischen Union auch Tschechien im November 2009 den Lissaboner Vertrag ratifiziert
hatte, konnte das Vertragswerk1 zum 01. Dezember 2009 in Kraft treten. Seither sind allerdings die mit der neuen Rechtsgrundlage der Europ?ischen Union verbundenen
vielf?ltigen Wirkungen kaum ins Bewusstsein der europ?ischen ?ffentlichkeit gelangt. Sie werden von den globalen Banken- und
Wirtschaftsproblemen sowie von der aktuellen Krise der europ?ischen W?hrungsunion überlagert, die die nationalen Politiken
der EU-Mitgliedstaaten und die gemeinschaftliche europ:aische Politik vor gro?e Herausforderungen stellen und deren Aufmerksamkeit
in hohem Ma?e in Anspruch nehmen. Es mag also noch dauern, bis Europa in absehbarer Zeit und hoffentlich ohne an seinen politischkonstitutiven
Fundamenten Schaden zu nehmen die aktuellen Krisen überwunden haben wird. Erst dann dürfte den Bürgerinnen und Bürgern Europas
deutlicher werden, dass mit dem Inkrafttreten des Vertrages von Lissabon eine unter mehreren Gesichtspunkten neue Epoche des
Europ?ischen Integrationsprozesses begonnen hat. Das gilt nicht nur, aber vor allem für die Innen- und Rechtspolitik — für
jene Bereiche europ?ischer Politik also, die die Herstellung des seit 1999 im Amsterdamer Vertrag avisierten „Raumes der Freiheit,
der Sicherheit und des Rechts“ zum Ziel haben. Innerhalb dieser im hohen Ma?e grundrechtssensiblen Politikfelder wird die
neue Epoche vor allem von erheblichen Ver?nderungen sowohl im materiellen, rechtlichen als auch im institutionellen, gerichtlichen
Schutz der Grund- und Freiheitsrechte der europ?ischen Bürgerinnen und Bürger gepr?gt sein. 相似文献
97.
饮料中的蛋白-多酚混浊 总被引:3,自引:0,他引:3
了解混浊活性(HA)蛋白和多酚的性质与相互作用,有助于生产出更好的饮料产品,使用更好的分析方法及稳定手段。 相似文献
98.
Matthias Engleder Dr. Tea Pavkov‐Keller Dr. Anita Emmerstorfer Altijana Hromic Sabine Schrempf Dr. Georg Steinkellner Dr. Tamara Wriessnegger Prof. Erich Leitner Dr. Gernot A. Strohmeier Dr. Iwona Kaluzna Dr. Daniel Mink Dr. Martin Schürmann Dr. Silvia Wallner Prof. Peter Macheroux Prof. Karl Gruber Dr. Harald Pichler 《Chembiochem : a European journal of chemical biology》2015,16(12):1730-1734
Hydratases provide access to secondary and tertiary alcohols by regio‐ and/or stereospecifically adding water to carbon‐carbon double bonds. Thereby, hydroxy groups are introduced without the need for costly cofactor recycling, and that makes this approach highly interesting on an industrial scale. Here we present the first crystal structure of a recombinant oleate hydratase originating from Elizabethkingia meningoseptica in the presence of flavin adenine dinucleotide (FAD). A structure‐based mutagenesis study targeting active site residues identified E122 and Y241 as crucial for the activation of a water molecule and for protonation of the double bond, respectively. Moreover, we also observed that two‐electron reduction of FAD results in a sevenfold increase in the substrate hydration rate. We propose the first reaction mechanism for this enzyme class that explains the requirement for the flavin cofactor and the involvement of conserved amino acid residues in this regio‐ and stereoselective hydration. 相似文献
99.
Structural Insights into the Recognition of N2‐Aryl‐ and C8‐Aryl DNA Lesions by the Repair Protein XPA/Rad14 下载免费PDF全文
Charlotte Ebert Nina Simon Dr. Sabine Schneider Prof. Dr. Thomas Carell 《Chembiochem : a European journal of chemical biology》2017,18(14):1379-1382
Aromatic amines are strongly carcinogenic. They are activated in the liver to give reactive nitrenium ions that react with nucleobases within the DNA duplex. The reaction occurs predominantly at the C8 position of the dG base, thereby giving C8‐acetyl‐aryl‐ or C8‐aryl‐dG adducts in an electrophilic aromatic substitution reaction. Alternatively, reaction with the exocyclic 2‐NH2 group is observed. Although the C8 adducts retain base‐pairing properties, base pairing is strongly compromised in the case of the N2 adducts. Here we show crystal structures of two DNA lesions, N2‐acetylnaphthyl‐dG and C8‐fluorenyl‐dG, within a DNA duplex recognized by the repair protein Rad14. The structures confirm that two molecules of the repair protein recognize the lesion and induce a 72 or 78° kink at the site of the damage. Importantly, the same overall kinked structure is induced by binding of the repair proteins, although the structurally different lesions result in distinct stacking interactions of the lesions within the duplex. The results suggest that the repair protein XPA/Rad14 is a sensor that recognizes flexibility. The protein converts the information that structurally different lesions are present in the duplex into a unifying sharply kinked recognition motif. 相似文献
100.
Dong H. Cha Alejandro E. Mieles Paola F. Lahuatte Andrea Cahuana Marie Piedad Lincango Charlotte E. Causton Sabine Tebbich Arno Cimadom Stephen A. Teale 《Journal of chemical ecology》2016,42(11):1101-1111
We investigated the role of olfactory cues from actively fermenting yeast (Saccharomyces cerevisiae) in attraction of adult Philornis downsi and identified two synergistically attractive yeast volatiles. Larvae of this invasive fly parasitize the hatchlings of passerines and threaten the Galapagos avifauna. Gas chromatography coupled with electroantennographic detection (GC-EAD), coupled gas chromatography-mass spectrometry (GC-MS), and field trapping experiments were used to identify volatile compounds from a yeast-sugar solution. EAD responses were consistently elicited by 14 yeast volatiles. In a series of field trapping experiments, a mixture of the 14 EAD-active compounds was similarly attractive to P. downsi when compared to the yeast-sugar solution, and we found that acetic acid and ethanol were essential for attraction. A mixture of 0.03 % acetic acid and 3 % ethanol was as attractive as the 14-component blend, but was not as attractive as the yeast-sugar solution. Philornis downsi showed positive and negative dose-responses to acetic acid in the ranges of 0.01 ~ 0.3 % and 0.3 ~ 9 %, respectively. Further optimization showed that the mixture of 1 % acetic acid and 3 % ethanol was as attractive as the yeast-sugar solution. Both mixtures of acetic acid and ethanol were more selective than the yeast-sugar solution in terms of non-target moths and Polistes versicolor wasps captured. These results indicate that acetic acid and ethanol produced by yeasts are crucial for P. downsi attraction to fermented materials on which they feed as adults and can be used to manage this invasive fly in Galapagos. 相似文献