排序方式: 共有124条查询结果,搜索用时 0 毫秒
61.
Green alga Zygnema was exposed to three concentrations of selenium and two levels of UV-B radiation. The combined effects of both treatments
on energy availability; photochemical quantum yield and respiratory potential were studied. Our findings show that traces
of selenium enhance metabolic process connected with photochemical quantum yield and mitochondrial respiration. Surprisingly,
selenium does not diminish the effects of UV-B radiation; on the contrary, the combined action of UV-B radiation and traces
of selenium leads to pronounced negative effects on photochemical quantum yield and the respiratory potential. Selenium is
involved in the activation of energy resources in green alga Zygnema. The importance of selenium for activity of the mitochondria is possibly an evolutionary recollection from an endosymbiotic
bacterium. 相似文献
62.
Superior Performance of Microporous Aluminophosphate with LTA Topology in Solar‐Energy Storage and Heat Reallocation 下载免费PDF全文
Andraž Krajnc Jure Varlec Matjaž Mazaj Alenka Ristić Nataša Zabukovec Logar Gregor Mali 《Liver Transplantation》2017,7(11)
Hydrophilic porous materials are recognized as very promising materials for water‐sorption‐based energy storage and transformation. In this study, a porous, zeolite‐like aluminophosphate with LTA (Linde Type A) topology is inspected as an energy‐storage material. The study is motivated by the material's high predicted pore volume. According to sorption and calorimetric tests, the aluminophosphate outperforms all other zeolite‐like and metal‐organic porous materials tested so far. It adsorbs water in an extremely narrow relative‐pressure interval (0.10 < p /p 0 < 0.15) and exhibits superior water uptake (0.42 g g?1) and energy‐storage capacity (527 kW h m?3). It also shows remarkable cycling stability; after 40 cycles of adsorption/desorption its capacity drops by less than 2%. Desorption temperature for this material, which is one of crucial parameters in applications, is lower from desorption temperatures of other tested materials by 10–15 °C. Furthermore, its heat‐pump performance is very high, allowing efficient cooling in demanding conditions (with cooling power up to 350 kW h m?3 even at 30 °C temperature difference between evaporator and environment). On the microscopic scale, sorption mechanism in AlPO4‐LTA is elucidated by X‐ray diffraction, nuclear magnetic resonance measurements, and first‐principles calculations. In this aluminophosphate, energy is stored predominately in hydrogen‐bonded network of water molecules within the pores. 相似文献
63.
Ent3p and Ent5p exhibit cargo-specific functions in trafficking proteins between the trans-Golgi network and the endosomes in yeast 下载免费PDF全文
The phosphoinositide-binding proteins Ent3p and Ent5p are required for protein transport from the trans-Golgi network (TGN) to the vacuole in Saccharomyces cerevisiae. Both proteins interact with the monomeric clathrin adaptor Gga2p, but Ent5p also interacts with the clathrin adaptor protein 1 (AP-1) complex, which facilitates retention of proteins such as Chs3p at the TGN. When both ENT3 and ENT5 are mutated, Chs3p is diverted from an intracellular reservoir to the cell surface. However, Ent3p and Ent5p are not required for the function of AP-1, but rather they seem to act in parallel with AP-1 to retain proteins such as Chs3p at the TGN. They have all the properties of clathrin adaptors, because they can both bind to clathrin and to cargo proteins. Like AP-1, Ent5p binds to Chs3p, whereas Ent3p facilitates the interaction between Gga2p and the endosomal syntaxin Pep12p. Thus, Ent3p has an additional function in Gga-dependent transport to the late endosome. Ent3p also facilitates the association between Gga2p and clathrin; however, Ent5p can partially substitute for this function. We conclude that the clathrin adaptors AP-1, Ent3p, Ent5p, and the Ggas cooperate in different ways to sort proteins between the TGN and the endosomes. 相似文献
64.
The decomposition of jellyfish after major bloom events results in the release of large amounts of nutrients, which can significantly
alter nutrient and oxygen dynamics in the surrounding environment. The response of the ambient bacterial community to decomposing
jellyfish biomass was evaluated in two marine ecosystems, the Gulf of Trieste (northern Adriatic Sea) and Big Lake (Mljet
Island, southern Adriatic Sea). The major difference between these two ecosystems is that Aurelia sp. medusae occur throughout the year in the oligotrophic Big Lake, whereas in the mesotrophic Gulf of Trieste, they occur
only seasonally and often as blooms. Addition of homogenized jellyfish to enclosed bottles containing ambient water from each
of these systems triggered considerable changes in the bacterial community dynamics and in the nutrient regime. The high concentrations
of protein, dissolved organic phosphorous (DOP), and PO4
3− immediately after homogenate addition stimulated increase in bacterial abundance and production rate, coupled with NH4
+ accumulation in both ecosystems. Our preliminary results of the bacterial community structure, as determined with denaturing
gradient gel electrophoresis, indicated differences in the bacterial community response between the two ecosystems. Despite
divergence in the bacterial community responses to jellyfish homogenate, increased bacterial biomass and growth rates in both
distinctive marine systems indicate potentially significant effects of decaying jellyfish blooms on microbial plankton. 相似文献
65.
Darko Perovic Marija Milavic Stjepan Dokuzovic Ivan Krezic Slaven Gojkovic Hrvoje Vranes Igor Bebek Vide Bilic Nenad Somun Ivan Brizic Ivan Skorak Klaudija Hriberski Suncana Sikiric Eva Lovric Sanja Strbe Milovan Kubat Alenka Boban Blagaic Anita Skrtic Sven Seiwerth Predrag Sikiric 《Current issues in molecular biology》2022,44(5):1901
Recently, marked therapeutic effects pertaining to the recovery of injured rat spinal cords (1 min compression injury of the sacrocaudal spinal cord (S2-Co1) resulting in tail paralysis) appeared after a single intraperitoneal administration of the stable gastric pentadecapeptide BPC 157 at 10 min post-injury. Besides the demonstrated rapid and sustained recovery (1 year), we showed the particular points of the immediate effect of the BPC 157 therapy that began rapidly after its administration, (i) soon after injury (10 min), or (ii) later (4 days), in the rats with a definitive spinal cord injury. Specifically, in counteracting spinal cord hematoma and swelling, (i) in rats that had undergone acute spinal cord injury, followed by intraperitoneal BPC 157 application at 10 min, we focused on the first 10–30 min post-injury period (assessment of gross, microscopic, and gene expression changes). Taking day 4 post-injury as the definitive injury, (ii) we focused on the immediate effects after the BPC 157 intragastric application over 20 min of the post-therapy period. Comparable long-time recovery was noted in treated rats which had definitive tail paralysis: (iii) the therapy was continuously given per orally in drinking water, beginning at day 4 after injury and lasting one month after injury. BPC 157 rats presented only discrete edema and minimal hemorrhage and increased Nos1, Nos2, and Nos3 values (30 min post-injury, (i)) or only mild hemorrhage, and only discrete vacuolation of tissue (day 4, (ii)). In the day 4–30 post-injury study (iii), BPC 157 rats rapidly presented tail function recovery, and no demyelination process (Luxol fast blue staining). 相似文献
66.
Hans-Josef Schroers Metka
erjav Alenka Munda Francois Halleen Pedro W. Crous 《Mycological Research》2008,112(1):82-92
A Cylindrocarpon species with up to 10 μm wide, straight and predominantly 3-septate macroconidia, subglobose to ovoidal microconidia and chlamydospores, is described as Cyl. pauciseptatum. It is most similar to Cyl. austrodestructans but no chlamydospores and microconidia are formed in the latter. Similar macroconidia also occur in Cyl. theobromicola, which forms oval to ellipsoidal microconidia at least sparsely and has slightly curved macroconidia, and Cyl. destructans var. crassum, which forms abundant 1-celled microconidia. DNA sequence data of the internal transcribed spacer regions 1 and 2 plus the 5.8S rDNA and the partial beta-tubulin gene were used for phylogenetic inferences. Cylindrocarpon pauciseptatum and Cyl. macrodidymum are monophyletic and are closely related to other species of Cylindrocarpon sensu stricto including members of the Cyl. destructans (teleomorph, Neonectria radicicola) species complex, which accommodates Cyl. liriodendri (teleomorph, Neon. liriodendri), Cyl. destructans var. crassum and Cyl. austrodestructans (teleomorph, Neonectria austroradicicola comb. nov.). Cylindrocarpon theobromicola is distantly related to species of Cylindrocarpon sensu stricto or Neonectria sensu stricto. It clustered among cylindrocarpon-like species with curved macroconidia, of which some belong to the Neon. mammoidea group. Relatively voluminous cells in sporodochial conidiophores of Cyl. theobromicola resembled those described for Campylocarpon, which is closely related to members of the Neon. mammoidea group including Cyl. theobromicola. Cylindrocarpon pauciseptatum has been isolated from roots of Vitis spp. in South-eastern Europe (Slovenia) as well as New Zealand, where it also occurs on roots of Erica melanthera. 相似文献
67.
The responses of Norway spruce [Picea abies (L.) Karst.] to enhanced UV-B radiation during the 5-year treatment performed outdoors have been subjected to ecophysiological
and growth analysis. The plants were exposed to UV-B radiation, simulating 17% ozone depletion. Ecophysiological parameters
were monitored three times a year on three needle age classes, while growth was analysed at the end of each growth season.
Spruce exhibited great variability in the amounts of photosynthetic pigments and methanol-soluble UV-B absorbing compounds,
light use efficiency, photosynthesis and respiratory potential. The needle, branch and plant biomass production was not significantly
affected during the 5-year treatment. The repeated-measures procedure comparing growth parameters through subsequent seasons,
revealed a decrease of branch diameter under enhanced UV-B, which could be interpreted as a cumulative UV-B effect. The effects
of UV-B radiation depended on needle development stage, interaction with environmental conditions and stresses. A reduced
negative effect of UV-B radiation was observed during the prolonged drought in 2003, which was hypothesised as an alleviating
effect. The tolerance of Norway spruce to elevated UV-B was to a large extent due to the high content of methanol-soluble
UV-B absorbing compounds that was related neither to environmental conditions, including UV-B dose, nor to the developmental
stage of the needles. The current year needles exhibited a tendency to increased production of UV-B absorbing compounds under
elevated UV-B radiation. The outdoor study performed under variable environmental conditions showed great complexity of spruce
response to enhanced UV-B. 相似文献
68.
Andrej Čokl Alenka Žunič Meta Virant-Doberlet 《Central European Journal of Biology》2011,6(3):431-439
The Asopinae (Heteroptera: Pentatomidae) are a subfamily of stinkbugs with predaceous feeding habits and poorly understood
communication systems. In this study we recorded vibratory signals emitted by Picromerus bidens L. on a non-resonant substrate and investigated their frequency characteristics. Males and females produced signals by vibration
of the abdomen and tremulation. The female and male songs produced by abdominal vibrations showed gender-specific time structure.
There were no differences in the temporal patterns of male or female tremulatory signals. The signals produced by abdominal
vibrations were emitted below 600 Hz whereas tremulatory signals had frequency ranges extending up to 4 kHz. Spectra of male
vibratory signals produced by abdominal vibrations contained different peaks, each of which may be dominant within the same
song sequence. Males alternated with each other during production of rivalry signals, using different dominant frequency levels.
We show that the vibratory song repertoire of P. bidens is broader than those of other predatory stinkbugs that have been investigated. The emission of vibrational signals with
different dominant frequencies but the same production mechanism has not yet been described in heteropteran insects, and may
facilitate location of individual sources of vibration within a group. 相似文献
69.
70.