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181.
Tom Deliens Benedicte Deforche Lieven Annemans Ilse De Bourdeaudhuij Peter Clarys 《PloS one》2016,11(11)
ObjectivesThis study examined the effect of a 10 and 20% meal price increase when choosing French fries and a 10 and 20% meal price reduction when choosing fruit for dessert on university students’ purchasing behaviour in an on-campus restaurant. The moderating effect of gender was also investigated. Secondly, this study aimed at gaining further insight into reasons why these price manipulations did or did not change students’ purchasing behaviour.SignificancePricing may be a promising strategy to improve university students’ eating behaviour. The likelihood of intervention success may increase when combining pricing strategies with offering healthy, tasty and meal matching starchy alternatives to French fries and offering a variety of fresh and appealing fruits. 相似文献
182.
Jelle Van Cauwenberg Veerle Van Holle Ilse De Bourdeaudhuij Peter Clarys Jack Nasar Jo Salmon Liesbet Goubert Benedicte Deforche 《PloS one》2014,9(11)
Experimental evidence of environmental features important for physical activity is challenging to procure in real world settings. The current study aimed to investigate the causal effects of environmental modifications on a photographed street''s appeal for older adults'' walking for transport. Secondly, we examined whether these effects differed according to gender, functional limitations, and current level of walking for transport. Thirdly, we examined whether different environmental modifications interacted with each other. Qualitative responses were also reported to gain deeper insight into the observed quantitative relationships. Two sets of 16 panoramic photographs of a streetscape were created, in which six environmental factors were manipulated (sidewalk evenness, traffic level, general upkeep, vegetation, separation from traffic, and benches). Sixty older adults sorted these photographs on appeal for walking for transport on a 7-point scale and reported qualitative information on the reasons for their rankings. Sidewalk evenness appeared to have the strongest influence on a street''s appeal for transport-related walking. The effect of sidewalk evenness was even stronger when the street''s overall upkeep was good and when traffic was absent. Absence of traffic, presence of vegetation, and separation from traffic also increased a street''s appeal for walking for transport. There were no moderating effects by gender or functional limitations. The presence of benches increased the streetscape''s appeal among participants who already walked for transport at least an hour/week. The protocols and methods used in the current study carry the potential to further our understanding of environment-PA relationships. Our findings indicated sidewalk evenness as the most important environmental factor influencing a street''s appeal for walking for transport among older adults. However, future research in larger samples and in real-life settings is needed to confirm current findings. 相似文献
183.
Ilse Foissner 《Protoplasma》1990,154(2-3):80-90
Summary The formation of wall appositions (plugs) by ionophore A 23187, CaCl2, LaCl3, and nifedipine was studied in mature internodal cells of characeaen algae. CaCl2 at concentrations above 10–2M induces thick fibrillar plugs without callose inNitella flexilis. InChara corallina andNitella flexilis ionophore A 23187 (1.25×10–5 to 5×10–5M) and LaCl3 (7.5×10–5 to 2.5×10–4M) cause flat appositions which contain callose and have a more granular structure. Plug formation by ionophore A 23187, CaCl2, and LaCl3 is pH-dependent and occurs beneath the alkaline regions of the cell. Nifedipine (10–4 to 10–5M) induces plugs inNitella flexilis after previous injury. These callose-containing wall appositions consist of a heterogeneous granular core which is covered by a fibrillar layer. The results of this work are compared with previous studies on wound wall formation and chlortetracycline (CTC)-induced plug formation which reveal that abundant coated vesicles occur only when a thick fibrillar wall layer is formed. Neither LaCl3 nor nifedipine inhibit the formation of CaCl2- or CTC-plugs. The unusual effects of these substances, which normally act as Ca2+ antagonists and therefore should prevent and not induce plug formation, are discussed. It is suggested that La3+ mimicks the effects of calcium and that nifedipine binding to the Ca2+ channels is altered in the alkaline regions of characean internodes and allows an influx of Ca2+.Abbreviations AFW
artificial fresh water
- CTC
chlortetracycline
- DCMU
dichlorphenyldimethylurea
- DMSO
dimethylsulfoxide
- EGTA
ethyleneglycoltetraacetic acid
- MES
2-(N-morpholino) ethanesulfonic acid
- HEPES
N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid
- TAPS
N-tris[hydroxymethyl]methyl-3-aminopropanesulfonic acid 相似文献
184.
Karl Jürss Ilse Junghahn Ralf Bastrop 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1992,162(4):345-350
Summary Protein synthesis-stimulating activity was assayed in the cytosolic fraction of white muscle from teleost fish (rainbow trout, carp) and of rat liver. In vitro protein synthesis-stimulating activity in the cytosolic fraction is reduced by food deprivation. The addition of elongation factors EF1, EF2, or EF1+EF2 compensates for the starvation-induced loss of protein synthesis-stimulating activity in trout muscle cytosol. The action of EF2 is stronger than that of EF1 in this respect. However, EF1 enhances in vitro protein synthesis-stimulating activity in rat liver cytosol more than EF2. The EF2 concentration in the cytosolic fraction of white muscle from starved trout is significantly lower than in fed specimens.Abbreviations EF
elongation factor(s)
- SGR
specific growth rate
- TCA
trichloroacetic acid 相似文献
185.
186.
Jure Škraban Ilse Cleenwerck Peter Vandamme Lijana Fanedl Janja Trček 《Systematic and applied microbiology》2018,41(6):581-592
Strains T5K1 and AV446 isolated from apple cider vinegars during a submerged vinegar production in two separate vinegar facilities showed 94% 16S rRNA gene similarity to its closest neighbors Komagataeibacter maltaceti LMG 1529T and Gluconacetobacter entanii LTH 4560T. Further phylogenetic and phenotypic characterizations indicated that the isolates belonged to a novel species of the Komagataeibacter genus. Comparison based on 16S–23S rRNA gene ITS sequences and concatenated partial sequences of the housekeeping genes dnaK, groEL and rpoB, grouped both strains to a single phylogenetic cluster well separated from the other species of the Komagataeibacter genus. Average nucleotide identity of T5K1 and AV446 draft genome sequences compared to other Komagataeibacter type strains was below 94% and at the same time, in-silico DNA–DNA hybridization was below 70%. Both strains on the other hand showed approximately 98% (average nucleotide identity) and 87% (in silico DNA–DNA hybridization) similarity to each other. Strains T5K1 and AV446 can be differentiated from other Komagataeibacter type strains based on their ability to produce 2-keto-d-gluconic acid and at the same time inability to produce 5-keto-d-gluconic acid. Furthermore, strains of the new species do not grow on Asai medium supplemented with d-glucose or d-mannitol. The growth is also absent (T5K1) or weak (AV446) on Hoyer–Frateur medium supplemented with afore mentioned sugars. Both strains produce cellulose. In addition, draft genome analysis revealed that strains T5K1 and AV446 possess genes involved in the synthesis of acetan-like extracellular heteropolysaccharide. We propose the name Komagataeibacter pomaceti sp. nov. for the new species with LMG 30150T [= CCM 8723T = ZIM B1029T] as the type strain. Data collected in this study and in a previous study also revealed that Komagataeibacter kombuchae is a later heterotypic synonym of Komagataeibacter hansenii. 相似文献
187.
188.
Abstract: Desiccation tolerance is a fundamental principle for resting stages of plant development which include the dormancy of seeds and the quiescent stages of resurrection plants. To prevent the deleterious effects of cellular desiccation, a complex interplay of several adaption mechanisms is required. The ability to cope with free radicals, the formation of which is well documented in desiccated tissues, is one of these basic requirements. Detoxification of free radicals by several antioxidants and scavenging enzymes include reactions of reduced glutathione (GSH) resulting in the formation of glutathione disulfide (GSSG). In free radical processing pathways GSSG is considered to be immediately reduced back to GSH by the action of glutathione reductase (EC 1.6.4.2.). However, in desiccated tissues GSSG accumulates. Protein-glutathione mixed disulfides (PSSG) are also reported to increase in plants under drought leading to the hypothesis that glutathione protects protein thiol groups from auto-oxidation. The irreversible formation of intramolecular disulfides resulting in denaturation of proteins would be one of the primary sites of desiccation injury. We suggest that PSSG is formed by the reaction of GSSG with high molecular weight thiols and introduce a thiol-disulfide cycle that involves reduction/oxidation processes of glutathione and protein thiol groups during the dehydration/rehydration processes in desiccation tolerant tissues. 相似文献
189.
Ilse C. Van Dromme Elsie Premereur Bram-Ernst Verhoef Wim Vanduffel Peter Janssen 《PLoS biology》2016,14(4)
The primate visual system consists of a ventral stream, specialized for object recognition, and a dorsal visual stream, which is crucial for spatial vision and actions. However, little is known about the interactions and information flow between these two streams. We investigated these interactions within the network processing three-dimensional (3D) object information, comprising both the dorsal and ventral stream. Reversible inactivation of the macaque caudal intraparietal area (CIP) during functional magnetic resonance imaging (fMRI) reduced fMRI activations in posterior parietal cortex in the dorsal stream and, surprisingly, also in the inferotemporal cortex (ITC) in the ventral visual stream. Moreover, CIP inactivation caused a perceptual deficit in a depth-structure categorization task. CIP-microstimulation during fMRI further suggests that CIP projects via posterior parietal areas to the ITC in the ventral stream. To our knowledge, these results provide the first causal evidence for the flow of visual 3D information from the dorsal stream to the ventral stream, and identify CIP as a key area for depth-structure processing. Thus, combining reversible inactivation and electrical microstimulation during fMRI provides a detailed view of the functional interactions between the two visual processing streams. 相似文献
190.
Hannah Verhoeven Dorien Simons Delfien Van Dyck Jelle Van Cauwenberg Peter Clarys Ilse De Bourdeaudhuij Bas de Geus Corneel Vandelanotte Benedicte Deforche 《PloS one》2016,11(1)