Characterization of the Impact of Wheat Stem Sawfly,Cephus cinctusNorton, on Pigment Composition and Photosystem Ii Photochemistry of Wheat Heads

Plants have evolved photoprotective mechanisms in order to counteract the damaging effects of excess light in hyper-arid desert environments. We evaluated the impact of surface canopy positions on the photosynthetic adjustments and chlorophyll fluorescence attributes (photosystem II photochemistry, quantum yield, fluorescence quenching, and photon energy dissipation), leaf biomass and nutrient content of sun-exposed leaves at the south east (SE canopy position) and shaded-leaves at the north west (NW canopy position) in the invasive Prosopis juliflora and native Prosopis cineraria in the extreme environment (hyper-arid desert area, United Arab Emirates (UAE)). The main aim of this research was to study the photoprotection mechanism in invasive and native Prosopis congeners via the safe removal—as thermal energy—of excess solar energy absorbed by the light collecting system, which counteracts the formation of reactive oxygen species. Maximum photosynthetic efficiency (Fv/Fm) from dark-adapted leaves in P. juliflora and P. cineraria was higher on NW than SE canopy position while insignificant difference was observed within the two Prosopis congeners. Greater quantum yield was observed in P. juliflora than P. cineraria on the NW canopy position than SE. With the change of canopy positions from NW to SE, the reduction of the PSII reaction center activity in the leaves of both Prosopis congeners was accelerated. On the SE canopy position, a significant decline in the electron transport rate (ETR) of in the leaves of both Prosopis congeners occurred, which might be due to the blockage of electron transfer from QA to QB on the PSII acceptor side. On the SE canopy position; Prosopis leaves dissipated excess light energy by increasing non-photochemical quenching (NPQ). However, in P. cineraria, the protective ability of NPQ decreased, which led to the accumulation of excess excitation energy (1 − qP)/NPQ and the aggravation of photoinhibition. The results also explain the role of different physiological attributes contributing to invasiveness of P. juliflora and to evaluate its liaison between plasticity of these characters and invasiveness.

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Characterization of photosystem II photochemistry in transgenic tobacco plants with lowered Rubisco activase content

Journal of Plant Physiology ◽

10.1016/j.jplph.2010.05.004 ◽

2010 ◽

Vol 167 (17) ◽

pp. 1457-1465 ◽

Cited By ~ 7

Author(s):

Bin Cai ◽

Aihong Zhang ◽

Zhipan Yang ◽

Qingtao Lu ◽

Xiaogang Wen ◽

...

Keyword(s):

Photosystem Ii ◽

Transgenic Tobacco ◽

Rubisco Activase ◽

Transgenic Tobacco Plants ◽

Tobacco Plants ◽

Photosystem Ii Photochemistry

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Photosynthetic pigment composition and photosystem II photochemistry of wheat ears

Plant Physiology and Biochemistry ◽

10.1016/j.plaphy.2004.02.008 ◽

2004 ◽

Vol 42 (5) ◽

pp. 395-402 ◽

Cited By ~ 21

Author(s):

Qingtao Lu ◽

Congming Lu

Keyword(s):

Photosystem Ii ◽

Photosynthetic Pigment ◽

Pigment Composition ◽

Photosystem Ii Photochemistry

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Characterization of photosystem II with the atomic-force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130365 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1146-1147

Author(s):

Kathleen M. Marr ◽

Mary K. Lyon

Keyword(s):

Photosystem Ii ◽

Atomic Force Microscope ◽

Three Dimensional ◽

Biologically Active ◽

Atomic Force ◽

Freeze Etching ◽

Image Averaging ◽

Oxygen Evolving ◽

Averaging Techniques

Photosystem II (PSII) is different from all other reaction centers in that it splits water to evolve oxygen and hydrogen ions. This unique ability to evolve oxygen is partly due to three oxygen evolving polypeptides (OEPs) associated with the PSII complex. Freeze etching on grana derived insideout membranes revealed that the OEPs contribute to the observed tetrameric nature of the PSIl particle; when the OEPs are removed, a distinct dimer emerges. Thus, the surface of the PSII complex changes dramatically upon removal of these polypeptides. The atomic force microscope (AFM) is ideal for examining surface topography. The instrument provides a topographical view of individual PSII complexes, giving relatively high resolution three-dimensional information without image averaging techniques. In addition, the use of a fluid cell allows a biologically active sample to be maintained under fully hydrated and physiologically buffered conditions. The OEPs associated with PSII may be sequentially removed, thereby changing the surface of the complex by one polypeptide at a time.

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The Analyses of Learning Strategies in English as a Second Language: Theoretical Classification and Measurement Test

Voices of English Language Education Society ◽

10.29408/veles.v4i2.2199 ◽

2020 ◽

Vol 4 (2) ◽

pp. 118-129

Author(s):

Asti Gumartifa ◽

◽

Indah Windra Dwie Agustiani

Keyword(s):

Language Learning ◽

Learning Outcomes ◽

Learning Strategies ◽

Learning Process ◽

English Learners ◽

English Language ◽

Point Of View ◽

Effective Learning ◽

The Impact

Gaining English language learning effectively has been discussed all years long. Similarly, Learners have various troubles outcomes in the learning process. Creating a joyful and comfortable situation must be considered by learners. Thus, the implementation of effective learning strategies is certainly necessary for English learners. This descriptive study has two purposes: first, to introduce the classification and characterization of learning strategies such as; memory, cognitive, metacognitive, compensation, social, and affective strategies that are used by learners in the classroom and second, it provides some questionnaires item based on Strategy of Inventory for Language Learning (SILL) version 5.0 that can be used to examine the frequency of students’ learning strategies in the learning process. The summary of this study explains and discusses the researchers’ point of view on the impact of learning outcomes by learning strategies used. Finally, utilizing appropriate learning strategies are certainly beneficial for both teachers and learners to achieve the learning target effectively.

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Modulation of Gut Microbiota and Oxidative Status by β-Carotene in Late Pregnant Sows

Frontiers in Nutrition ◽

10.3389/fnut.2020.612875 ◽

2020 ◽

Vol 7 ◽

Author(s):

Xupeng Yuan ◽

Jiahao Yan ◽

Ruizhi Hu ◽

Yanli Li ◽

Ying Wang ◽

...

Keyword(s):

Gut Microbiota ◽

Dietary Supplementation ◽

Basal Diet ◽

Fecal Microbiota ◽

Control Group ◽

Metabolic Activities ◽

The Impact ◽

Positive Effect ◽

Β Carotene

Recent evidences suggest that gut microbiota plays an important role in regulating physiological and metabolic activities of pregnant sows, and β-carotene has a potentially positive effect on reproduction, but the impact of β-carotene on gut microbiota in pregnant sows remains unknown. This study aimed to explore the effect and mechanisms of β-carotene on the reproductive performance of sows from the aspect of gut microbiota. A total of 48 hybrid pregnant sows (Landrace × Yorkshire) with similar parity were randomly allocated into three groups (n = 16) and fed with a basal diet or a diet containing 30 or 90 mg/kg of β-carotene from day 90 of gestation until parturition. Dietary supplementation of 30 or 90 mg/kg β-carotene increased the number of live birth to 11.82 ± 1.54 and 12.29 ± 2.09, respectively, while the control group was 11.00 ± 1.41 (P = 0.201). Moreover, β-carotene increased significantly the serum nitric oxide (NO) level and glutathione peroxidase (GSH-Px) activity (P < 0.05). Characterization of fecal microbiota revealed that 90 mg/kg β-carotene increased the diversity of the gut flora (P < 0.05). In particular, β-carotene decreased the relative abundance of Firmicutes including Lachnospiraceae AC2044 group, Lachnospiraceae NK4B4 group and Ruminococcaceae UCG-008, but enriched Proteobacteria including Bilophila and Sutterella, and Actinobacteria including Corynebacterium and Corynebacterium 1 which are related to NO synthesis. These data demonstrated that dietary supplementation of β-carotene may increase antioxidant enzyme activity and NO, an important vasodilator to promote the neonatal blood circulation, through regulating gut microbiota in sows.

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Clonal approaches to understanding the impact of mutations on hematologic disease development

Blood ◽

10.1182/blood-2018-11-835405 ◽

2019 ◽

Vol 133 (13) ◽

pp. 1436-1445 ◽

Cited By ~ 6

Author(s):

Jyoti Nangalia ◽

Emily Mitchell ◽

Anthony R. Green

Keyword(s):

Somatic Mutations ◽

Clonal Selection ◽

Single Cells ◽

Driver Mutations ◽

Great Promise ◽

Tumor Evolution ◽

Disease Development ◽

Hematopoietic Tissue ◽

The Impact

Abstract Interrogation of hematopoietic tissue at the clonal level has a rich history spanning over 50 years, and has provided critical insights into both normal and malignant hematopoiesis. Characterization of chromosomes identified some of the first genetic links to cancer with the discovery of chromosomal translocations in association with many hematological neoplasms. The unique accessibility of hematopoietic tissue and the ability to clonally expand hematopoietic progenitors in vitro has provided fundamental insights into the cellular hierarchy of normal hematopoiesis, as well as the functional impact of driver mutations in disease. Transplantation assays in murine models have enabled cellular assessment of the functional consequences of somatic mutations in vivo. Most recently, next-generation sequencing–based assays have shown great promise in allowing multi-“omic” characterization of single cells. Here, we review how clonal approaches have advanced our understanding of disease development, focusing on the acquisition of somatic mutations, clonal selection, driver mutation cooperation, and tumor evolution.

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