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981.
Reis Bruna Paolinelli Szitár Katalin Kövendi-Jakó Anna Török Katalin Sáradi Nóra Csákvári Edina Halassy Melinda 《Landscape and Ecological Engineering》2022,18(4):429-440
Landscape and Ecological Engineering - To help upscale ecological restoration of degraded lands, landscape factors and longer time scales should be considered when assessing restoration efforts. We... 相似文献
982.
Eric Cornes Montserrat Porta-De-La-Riva David Aristizábal-Corrales Ana María Brokate-Llanos Francisco Javier García-Rodríguez Iris Ertl Mònica Díaz Laura Fontrodona Kadri Reis Robert Johnsen David Baillie Manuel J. Mu?oz Mihail Sarov Denis Dupuy Julián Cerón 《RNA (New York, N.Y.)》2015,21(9):1544-1553
983.
984.
985.
Birgit Gemeinholzer Laura Demant Martin Dieterich Uta Eser Nina Farwig Christian Geske Heike Feldhaar Daniel Lauterbach Michael Reis Wolfgang Weisser Klaus Werk 《当今生物学》2019,49(6):444-455
Species loss despite nature conservation: need for action and research About 40 per cent of all plant and animal species occurring in Germany (insects, mammals, fish, birds, amphibians and reptiles) are endangered or threatened with extinction; 3–4 per cent are already considered lost. A comparison with other European countries shows that the risk situation in Germany is also very serious from an international point of view. In order to better anchor nature conservation in modern society as a prerequisite for globally sustainable development, it is necessary (1) to rethink and change the actions of each individual through education, communication and discussion; (2) to refocus policy and existing funding instruments; (3) to strengthen biodiversity and nature conservation concerns in and through universities and colleges, and (4) to invest in nature conservation in order to preserve nature as the basis of human life (ecosystem services) and on account of its intrinsic value. Conservation must be economically viable. This should not only be the case for farmers, but also for any land use that meets the requirements of nature conservation. Any conservation effort should be rewarded. To ensure that the actually set and clearly defined objectives of the EU nature conservation directives can be achieved, the Federal Working Group on Nature Conservation, Landscape Conservation and Recreation (LANA) predicts that at least 1.4 billion euros additionally will be needed annually. This would correspond to about 17 euros per inhabitant and year. This comparatively small amount would more than double the budget available in Germany for the protection of biodiversity. 相似文献
986.
Gabriela da Silva Luís Felipe Costa Ramos Henrique dos Santos Seckler Fabio Mendona Gomes Juliana Reis Cortines Isabela Ramos Cristiane Dinis Anobom Ednildo de Alcantara Machado Danielle Maria Perptua de Oliveira 《Archives of insect biochemistry and physiology》2019,102(1)
In Brazil, the use of transgenic plants expressing the insect‐toxic Bacillus thuringiensis endotoxin has been successfully used as pest control management since 2013 in transgenic soybean lineages against pest caterpillars such as Helicoverpa armigera. These toxins, endogenously expressed by the plants or sprayed over the crops, are ingested by the insect and bind to receptors in the midgut of these animals, resulting in disruption of digestion and lower insect survival rates. Here, we identified and characterized a membrane‐associated alkaline phosphatase (ALP) in the midgut of Anticarsia gemmatalis, the main soybean defoliator pest in Brazil, and data suggested that it binds to Cry1Ac toxin in vitro. Our data showed a peak of ALP activity in homogenate samples of the midgut dissected from the 4th and 5th instars larvae. The brush border membrane vesicles obtained from the midgut of these larvae were used to purify a 60 kDa ALP, as detected by in‐gel activity and in vitro biochemical characterization using pharmacological inhibitors and mass spectrometry. When Cry1Ac toxin was supplied to the diet, it was efficient in decreasing larval weight gain and survival. Indeed, in vitro incubation of Cry1Ac toxin with the purified ALP resulted in a 43% decrease in ALP specific activity and enzyme‐linked immunosorbent assay showed that ALP interacts with Cry1Ac toxin in vitro, thus suggesting that ALP could function as a Cry toxin ligand. This is a first report characterizing an ALP in A. gemmatalis. 相似文献
987.
In-water ships’ hull cleaning enables significant fuel savings through removal of marine fouling from surfaces. However, cleaning may also shorten the lifetime of hull coatings, with a subsequent increase in the colonization and growth rate of fouling organisms. Deleterious effects of cleaning would be minimized by matching cleaning forces to the adhesion strength of the early stages of fouling, or microfouling. Calibrated waterjets are routinely used to compare different coatings in terms of the adhesion strength of microfouling. However, an absolute scale is lacking for translating such results into cleaning forces, which are of interest for the design and operation of hull cleaning devices. This paper discusses how such forces can be determined using computational fluid dynamics. Semi-empirical formulae are derived for forces under immersed waterjets, where the normal and tangential components of wall forces are given as functions of different flow parameters. Nozzle translation speed is identified as a parameter for future research, as this may affect cleaning efficacy. 相似文献
988.
Cipolla L Fernandes MR Gregori M Airoldi C Nicotra F 《Carbohydrate research》2007,342(12-13):1813-1830
Novel nojirimycin-derived bicyclic structures, containing cyclic carbamate, urea and guanidine moieties have been synthesised starting from suitably protected alpha-C-vinylnojirimycin and alpha-C-allylnojirimycin, respectively, and their biological activity against different glycosidases and as antibacterial agents tested. 相似文献
989.
Assessing the effects of surfactants on the physical properties of liposome membranes 总被引:1,自引:0,他引:1
Knowledge of the partition process of environmentally significant molecules between biological membranes and their surroundings is of vital importance to explain their activity and toxicity, as well as phenomena like absorption, distribution and metabolism. In this research effort, we have studied membrane interactions of three surfactants: t-octylphenoxypolyethoxyethanol (Triton X-100), cetyltrimethylammonium chloride (CTAC) and dodecylbenzene sulphonate (SDBS). Unilamellar liposomes (LUVs) of egg yolk phosphatidylcholine (EPC) were used as membrane models. The partition coefficient, a fundamental parameter in assessing the behaviour of xenobiotic compounds, was determined for SDBS and Triton X-100 by derivative spectrophotometry and fluorescence quenching. The effect of these surfactants upon the physico-chemical characteristics (fluidity, diameter and surface charge) of the liposome membrane was also determined. Results show that all the three surfactants cause an increase in fluidity of the liposome membrane, although for low surfactant concentrations uncharacteristic membrane rigidity was observed, probably due to a change in lipid packing density. 相似文献
990.
Vieira LB Pimenta AM Richardson M Bemquerer MP Reis HJ Cruz JS Gomez MV Santoro MM Ferreira-de-Oliveira R Figueiredo SG Snutch TP Cordeiro MN 《Cellular and molecular neurobiology》2007,27(1):129-146
Summary Various neurotoxins have been described from the venom of the Brazilian spider Phoneutria nigriventer, but little is known about the venoms of the other species of this genus. In the present work, we describe the purification
and some structural and pharmacological features of a new toxin (PRTx3-7) from Phoneutria reidyi that causes flaccid paralysis in mice. The observed molecular mass (4627.26 Da) was in accordance with the calculated mass
for the amidated form of the amino acid sequence (4627.08 Da). The presence of an α-amidated C-terminus was confirmed by MS/MS
analysis of the C-terminal peptide, isolated after enzymatic digestion of the native protein with Glu-C endoproteinase. The
purified protein was injected (intracerebro-ventricular) into mice at dose levels of 5 μg/mouse causing immediate agitation
and clockwise gyration, followed by the gradual development of general flaccid paralysis. PRTx3-7 at 1 μM inhibited by 20%
the KCl-induced increase on [Ca2+]i in rat brain synaptosomes. The HEK cells permanently expressing L, N, P/Q and R HVA Ca2+ channels were also used to better characterize the pharmacological features of PRTx3-7. To our surprise, PRTx3-7 shifted
the voltage-dependence for activation towards hyperpolarized membrane potentials for L (−4 mV), P/Q (−8 mV) and R (−5 mV)
type Ca2+ currents. In addition, the new toxin also affected the steady state of inactivation of L-, N- and P/Q-type Ca2+ currents.
L. B. Vieira and A. M. C. Pimenta contributed equally to this work. 相似文献