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8463. Ferredoxin-quinone reductase benefits cyclic electron flow around photosystem 1 in tobacco leaves upon exposure to chilling stress under low irradiance

Creator:
Li, X.-G., Xu, P.-L., Zhao, J.-P., Meng, J.-J., and He, Q.-W.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chlorophyll fluorescence, cyclic electron flow, ferrodoxin quinone reductase, Nicotiana, non-photochemical quenching, photosystem 2, and xanthophyll cycle
Language:
Multiple languages
Description:
The function of chloroplast ferredoxin quinone reductase (FQR)-dependent flow was examined by comparing a wild type tobacco and a tobacco transformant (ΔndhB) in which the ndhB gene had been disrupted with their antimycin A (AA)-fed leaves upon exposure to chilling temperature (4 °C) under low irradiance (100 µmol m-2 s-1 photon flux density). During the chilling stress, the maximum photochemical efficiency of photosystem (PS) 2 (Fv/Fm) decreased markedly in both the controls and AA-fed leaves, and P700+ was also lower in AA-fed leaves than in the controls, implying that FQR-dependent cyclic electron flow around PS1 functioned to protect the photosynthetic apparatus from chilling stress under low irradiance. Under such stress, non-photochemical quenching (NPQ), particularly the fast relaxing NPQ component (qf) and the de-epoxidized ratio of the xanthophyll cycle pigments, (A+Z)/(V+A+Z), formed the difference between AA-fed leaves and controls. The lower NPQ in AA-fed leaves might be related to an inefficient proton gradient across thylakoid membranes (ΔpH) because of inhibiting an FQR-dependent cyclic electron flow around PS1 at chilling temperature under low irradiance. and X.-G. Li ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8464. Ferredoxin: the central hub connecting photosystem I to cellular metabolism

Creator:
Mondal, J. and Bruce, B. D.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
přenos elektronů, electron transfer, cellular metabolism, ferredoxin, global interaction, oxidation-reduction, 2, and 581
Language:
Multiple languages
Description:
Ferredoxin (Fd) is a small soluble iron-sulfur protein essential in almost all oxygenic photosynthetic organisms. It contains a single [2Fe-2S] cluster coordinated by four cysteine ligands. It accepts electrons from the stromal surface of PSI and facilitates transfer to a myriad of acceptors involved in diverse metabolic processes, including generation of NADPH via Fd-NADP-reductase, cyclic electron transport for ATP synthesis, nitrate reduction, nitrite reductase, sulfite reduction, hydrogenase and other reductive reactions. Fd serves as the central hub for these diverse cellular reactions and is integral to complex cellular metabolic networks. We describe advances on the central role of Fd and its evolutionary role from cyanobacteria to algae/plants. We compare structural diversity of Fd partners to understand this orchestrating role and shed light on how Fd dynamically partitions between competing partner proteins to enable the optimum transfer of PSI-derived electrons to support cell growth and metabolism., J. Mondal, B. D. Bruce., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8465. Ferroptosis-related long noncoding RNA signature predicts prognosis of clear cell renal carcinoma

Creator:
Liu, J. W., Supandi, F., and Dhillon, Sarinder Kaur
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
clear cell renal carcinoma, ferroptosis, long noncoding RNA, prognosis, and biomarker
Language:
English
Description:
Clear cell renal cell carcinoma (ccRCC) is very common and accounts for most kidney cancer deaths. While many studies are being conducted in finding the prognostic signatures of ccRCC, we believe that ferroptosis, which involves programmed cell death dependent on iron accumulation, has therapeutic potential in ccRCC. Recent research has shown that long noncoding RNAs (lncRNAs) are involved in ferroptosis-related tumour processes and are closely related to survival in patients with ccRCC. Hence, in this study we aim to further explore the role of ferroptosis-related lncRNAs (FRLs) in ccRCC, hoping to establish a signature to predict the survival outcome of ccRCC. We analysed transcriptome data from The Cancer Genome Atlas database (TCGA) and ferroptosis-related genes (FRGs) from FerrDb to identify FRLs using Pearson’s correlation. Lasso Cox regression analysis and multivariate Cox proportional hazards models screened seventeen optimal FRLs for developing prognostic signatures. Kaplan-Meier survival curves and ROC curves were then plotted for validating the sensitivity, specificity, and accuracy of the identified signatures. Gene Set Enrichment Analysis and CIBERSORT algorithm were deployed to explore the role of these FRLs in the tumour microenvironment. It was concluded that these models demonstrate excellent performance in predicting prognosis among patients with ccRCC, also indicating association with the clinicopathologic parameters such as tumour grade, tumour stage and tumour immune infiltration. In conclusion, our findings provide novel insights into ferroptosis-related lncRNAs in ccRCC, which are important targets for investigating the tumorigenesis of ccRCC.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8466. Fertilization regimes under hot conditions alter photosynthetic response of bean plants

Creator:
Hassan, I. A., Abou Zeid, H. M., Taia, W., Haiba, N. S., Zahran, A., Badr, R. H., El Dakak, R. A., and Shalaby, E. A.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, fazol obecný, photosynthesis, Phaseolus vulgaris, heat stress, nitrogen fertilization, photosynthetic performance, Phaseolus vulgaris L, French bean, 2, and 581
Language:
Multiple languages
Description:
We examined the effects of foliar application of various nitrogen (urea) concentrations on gas-exchange and chlorophyll (Chl) fluorescence characteristics in bean plants treated by heat stress (42/30°C, day/night temperatures). Heat stress caused reductions in contents of Chl a, Chl b, and in maximum photochemical efficiency of PSII by 13, 20, and 27%, respectively, regardless of the N treatment. However, N fertilization caused significant increases in these parameters, especially at higher N concentrations. The net photosynthetic rate and stomatal conductance were enhanced by 32, 60, and 69% and by 25, 88, and 100% due to addition of 5, 10, and 15 mM N, respectively. However, gas-exchange parameters were reduced by 24% due to heat stress. N fertilization alleviated adverse effects of heat stress., I. A. Hassan, H. M. Abou Zeid, W. Taia, N. S. Haiba, A. Zahran, R. H. Badr, R. A. El Dakak, E. A. Shalaby., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8467. Festivity vesnické komunity z pohledu školních kronik. Sondy do záznamů školních kronik vybraných lokalit z konce 19. století

Creator:
Valešová, Barbora and Kuthanová, Veronika
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chronicle, school, festivity, teacher, and students
Language:
Czech
Description:
Spreading of school chronicles in the second half of the 19th century allows collection of information from larger geographic areas.Despite being significantly different in terms of length and nature of records, individual chronicles represent a valuable source of information for researchers. Authors of the chronicles were teachers, through whom we find out more about the lives of school children, troubles of teachers in the 19th century or about disputes accompanying attempts to build own schools in municipalities, but also about municipalities themselves, national and international events and natural disasters.The paper focused on festivities in a social group of the municipality from the perspective of school chronicles as a unique and not quite yet explored source. Thanks to these records, it is possible to rebuild the course of official visits of high state and church representatives, sanctification of buildings or celebrations of Christmas trees, but mainly the position of the school and its involvement in social life. Thanks to the chronological recording, the development of the festive life in the municipality can be observed, and despite the fact that it is primarily a source from the school environment, information recorded in it is of indisputable importance for the creation of a complex view of the culture and life in a municipality in the 19th century.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

8469. Feyerabend’s alternative theories within goodman’s worldmaking

Creator:
Fišerová, Nicole
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
alternative theories, methodological anarchism, Nelson Goodman, Paul Feyerabend, philosophy of science, theory of symbols, worldmaking, and world-versions
Language:
Slovak
Description:
The main purpose of this paper is to compare two pluralistic approaches to knowledge, Goodman’s theory of worldmaking and Feyerabend’s methodological anarchism. It therefore examines firstly, the concept of world-versions, which according to Goodman create our worlds and at the same time are crucial for achieving a better understanding of reality; and secondly, the concept of alternative theories which are built upon pluralism and, according to Feyerabend, secure knowledge and make scientific progress possible. Feyerabend’s concept has been rejected by many, seemingly for its lack of limitations. In line with this argument, I propose that based on the comparison of these two pluralistic approaches, the alternative theories can be understood as a part of worldmaking, for Goodman’s theory has wider applicability since it encompasses not only science but also art. Furthermore, I suggest adopting Goodman’s principle of rightness, the criterion of functionality in his worldmaking, as a criterion within Feyerabend’s methodological anarchism when establishing the prevailing theory. It is to be expected that such a juxtaposition will uncover inconsistencies, in particular regarding boundless relativism and the vague terminology in both conceptions.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

8470. Fiber product preserving bundle functors as modified vertical Weil functors

Creator:
Mikulski , Włodzimierz M.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, Weil algebra, Weil functor, vertical Weil functor, Weil algebra bundle functor, modified Weil functor, modified vertical Weil functor, bundle functor, fiber product preserving bundle functor, natural transformation, 13, and 51
Language:
English
Description:
We introduce the concept of modified vertical Weil functors on the category \mathcal{F}\mathcal{M}_m of fibred manifolds with m-dimensional bases and their fibred maps with embeddings as base maps. Then we describe all fiber product preserving bundle functors on \mathcal{F}\mathcal{M}_m in terms of modified vertical Weil functors. The construction of modified vertical Weil functors is an (almost direct) generalization of the usual vertical Weil functor. Namely, in the construction of the usual vertical Weil functors, we replace the usual Weil functors T^{a} corresponding to Weil algebras A by the so called modified Weil functors T^{a} corresponding to Weil algebra bundle functors A on the category \mathcal{F}\mathcal{M}_m of m-dimensional manifolds and their embeddings., Włodzimierz M. Mikulski., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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