Regulatory mechanisms associating innate leaves senescence of incongruent species

Background: Senescence is the final developmental phase of a leaf which starts with nutrient salvage and ends with cell death. The first visible event during senescence is leaf yellowing, which typically starts at the leaf margins and progresses to the interior of the leaf blade. Though, regulators of senescence adopt a range of physiological and developmental mechanisms which undergo senescence of plant.Methods: Leaves of different species were collected from the green house, and then rinsed several times with sterilized distilled water. For discs of leaves, two same sized leaves were collected and made the same sized discs. The samples were infiltrated with specific senescence inhibitor. The discs then kept in distilled water and placed under condition at 250 C. Observed the phenotypes at two days interval, molecular based analysis was perfumed at 8th day of infiltration. Results: In this study, innate senescence approach comparison to inhibitor based senescence has been performed in order to check its consequences on leaves of different crops such as; cauliflower, apple, tobacco, rose and Arabidopsis. Arabidopsis and apple have resulted in a narrative phenotype with high level of ion leakage. While in case of rose and cauliflower, the phenotype was characterized with yellow fading of leaves. Interestingly, in the tobacco plants, intense yellowing of leaves developed along bottom. Further, in order to confirm the efficiency and pattern of senescence, we had also assessed the changes occurred during leaf senescence via ion leakage and chlorophyll content, expression of SAG12 (a senescence associated gene) and (PSA) photosynthetic associated genes expression as markers.Conclusions: It has been noted that progression of leaf senescence is a very critical and important factors affecting plant growth and development. It can be stated that initiation of leaves senescence can be controlled by using specific inhibitor.

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Characterization and Mapping of a Novel Premature Leaf Senescence Mutant in Common Tobacco (Nicotiana tabacum L.)

Plants ◽

10.3390/plants8100415 ◽

2019 ◽

Vol 8 (10) ◽

pp. 415 ◽

Cited By ~ 1

Author(s):

Xiaoming Gao ◽

Xinru Wu ◽

Guanshan Liu ◽

Zenglin Zhang ◽

Jiangtao Chao ◽

...

Keyword(s):

Nicotiana Tabacum ◽

Leaf Senescence ◽

Genetic Manipulation ◽

Recessive Gene ◽

Marker Genes ◽

Regulation Mechanism ◽

Nicotiana Tabacum L ◽

Genes Expression ◽

Leaf Yellowing ◽

Premature Leaf Senescence

As the last stage of plant development, leaf senescence has a great impact on plant’s life cycle. Genetic manipulation of leaf senescence has been used as an efficient approach in improving the yield and quality of crop plants. Here we describe an ethyl methane sulfonate (EMS) mutagenesis induced premature leaf senescence mutant yellow leaf 1 (yl1) in common tobacco (Nicotiana tabacum L.). The yl1 plants displayed early leaf yellowing. Physiological parameters and marker genes expression indicated that the yl1 phenotype was caused by premature leaf senescence. Genetic analyses indicated that the yl1 phenotype was controlled by a single recessive gene that was subsequently mapped to a specific interval of tobacco linkage group 11 using simple sequence repeat (SSR) markers. Exogenous plant hormone treatments of leaves showed that the yl1 mutant was more sensitive to ethylene and jasmonic acid than the wild type. No similar tobacco premature leaf senescence mutants have been reported. This study laid a foundation for finding the gene controlling the mutation phenotype and revealing the molecular regulation mechanism of tobacco leaf senescence in the next stage.

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Subjective factors affecting gun shooting accuracy among employees of internal affairs agencies in process of learning

Vestnik of the St. Petersburg University of the Ministry of Internal Affairs of Russia ◽

10.35750/2071-8284-2020-4-198-206 ◽

2020 ◽

Vol 2020 (4) ◽

pp. 198-206

Author(s):

Anton Rozhkov ◽

Anton Popov ◽

Vitaliy Balahonskiy

Keyword(s):

Subjective Experience ◽

Statistical Significance ◽

Self Regulation ◽

Sensorimotor Coordination ◽

Factors Affecting ◽

Intelligent Behavior ◽

Experience Of Stress ◽

Firing Line ◽

High Level ◽

In Fire

The article is devoted to the study of subjective factors affecting shooting accuracy of law enforcement officers. The empirical study identified some subjective factors reducing gun shooting accuracy and effectiveness among law enforcers. These characteristics include sensorimotor coordination and subjective experience of stress during the shooting process. Scientific analysis made it possible to determine statistical significance of the influence of these factors on the accuracy of shooting. To increase the effectiveness of shooting among officers with a low index of sensorimotor coordination, the authors suggest using exercises aimed at cultivating sensorimotor coordination in fire training classes. While working with employees being under a high level of subjectively experienced stress, more attention should be paid to training techniques to overcome stress and form intelligent behavior in extreme situations. The authors also draw readers’ attention to factors increasing the effectiveness of shooting: officers’ ability to determine the subjective level of stress, their knowledge of emotional self-regulation techniques, knowledge of the sequence of their actions in the firing line.

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Strategies for a Circular Economy in the Construction and Demolition Sector: Identifying the Factors Affecting the Recommendation of Recycled Concrete

Sustainability ◽

10.3390/su13084113 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4113

Author(s):

Valeria Superti ◽

Cynthia Houmani ◽

Ralph Hansmann ◽

Ivo Baur ◽

Claudia R. Binder

Keyword(s):

Circular Economy ◽

A Priori ◽

Recycled Concrete ◽

Recycled Aggregates ◽

Factors Affecting ◽

Structural Applications ◽

Adoption Of Innovation ◽

Decision Making Processes ◽

Behavioural Factors ◽

High Level

With increasing urbanisation, new approaches such as the Circular Economy (CE) are needed to reduce resource consumption. In Switzerland, Construction & Demolition (C&D) waste accounts for the largest portion of waste (84%). Beyond limiting the depletion of primary resources, implementing recycling strategies for C&D waste (such as using recycled aggregates to produce recycled concrete (RC)), can also decrease the amount of landfilled C&D waste. The use of RC still faces adoption barriers. In this research, we examined the factors driving the adoption of recycled products for a CE in the C&D sector by focusing on RC for structural applications. We developed a behavioural framework to understand the determinants of architects’ decisions to recommend RC. We collected and analysed survey data from 727 respondents. The analyses focused on architects’ a priori beliefs about RC, behavioural factors affecting their recommendations of RC, and project-specific contextual factors that might play a role in the recommendation of RC. Our results show that the factors that mainly facilitate the recommendation of RC by architects are: a senior position, a high level of RC knowledge and of the Minergie label, beliefs about the reduced environmental impact of RC, as well as favourable prescriptive social norms expressed by clients and other architects. We emphasise the importance of a holistic theoretical framework in approaching decision-making processes related to the adoption of innovation, and the importance of the agency of each involved actor for a transition towards a circular construction sector.

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Study on Tourism Flow Network Patterns on May Day Holiday

Sustainability ◽

10.3390/su13020947 ◽

2021 ◽

Vol 13 (2) ◽

pp. 947

Author(s):

Shanshan Wu ◽

Lucang Wang ◽

Haiyang Liu

Keyword(s):

Transportation Network ◽

Edge Structure ◽

Flow Network ◽

Factors Affecting ◽

Spatial Distribution Characteristics ◽

Transportation Modes ◽

May Day ◽

High Level ◽

Network Patterns ◽

Main Factor

The development of tourism is based on tourism flow and studying a tourism flow network can help to elucidate its mechanism of operation. Transportation network is the path to realize the spatial displacement of tourism flow. This study used “Tencent migration” big data to explore the spatial distribution characteristics and rules of tourism flow in China, providing suggestions for the development of tourism. The results demonstrate that the 361 cities studied can be divided into three types: destination-oriented, tourist-origin-oriented, and destination-oriented and tourist-origin-oriented. There are significant differences in the quantity of flow, the area of concentration, and the factors affecting the flow in the three types of cities. The larger the flow of tourism between cities, the higher the network level, and the wider the network range. The high-level nodes are closely related, while the peripheral nodes are more widely distributed, with weak attractiveness and inconvenient traffic, forming a “core-edge” structure. Different network patterns are established for different modes of transportation. The degree of response of different types of transportation to distance is the main factor influencing the network patterns of diverse paths. These findings have practical implications for the choice of appropriate travel destinations and transportation modes for tourists.

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High expression of fibroblast activation protein (FAP) predicts poor outcome in high-grade serous ovarian cancer

BMC Cancer ◽

10.1186/s12885-020-07541-6 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Min Li ◽

Xue Cheng ◽

Rong Rong ◽

Yan Gao ◽

Xiuwu Tang ◽

...

Keyword(s):

Ovarian Cancer ◽

Cox Regression ◽

Paraffin Section ◽

Progression Free Survival ◽

High Grade ◽

Serous Ovarian Cancer ◽

Systematic Analysis ◽

Cox Regression Analysis ◽

Genes Expression ◽

High Level

Abstract Background High-grade serous ovarian cancer (HGSOC) is a fatal form of ovarian cancer. Previous studies indicated some potential biomarkers for clinical evaluation of HGSOC prognosis. However, there is a lack of systematic analysis of different expression genes (DEGs) to screen and detect significant biomarkers of HGSOC. Methods TCGA database was conducted to analyze relevant genes expression in HGSOC. Outcomes of candidate genes expression, including overall survival (OS) and progression-free survival (PFS), were calculated by Cox regression analysis for hazard rates (HR). Histopathological investigation of the identified genes was carried out in 151 Chinese HGSOC patients to validate gene expression in different stages of HGSOC. Results Of all 57,331 genes that were analyzed, FAP was identified as the only novel gene that significantly contributed to both OS and PFS of HGSOC. In addition, FAP had a consistent expression profile between carcinoma-paracarcinoma and early-advanced stages of HGSOC. Immunological tests in paraffin section also confirmed that up-regulation of FAP was present in advanced stage HGSOC patients. Prediction of FAP network association suggested that FN1 could be a potential downstream gene which further influenced HGSOC survival. Conclusions High-level expression of FAP was associated with poor prognosis of HGSOC via FN1 pathway.

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Understanding employee turnover in humanitarian organizations

Industrial and Commercial Training ◽

10.1108/ict-10-2015-0067 ◽

2016 ◽

Vol 48 (4) ◽

pp. 208-214 ◽

Cited By ~ 17

Author(s):

Rameshwar Dubey ◽

Angappa Gunasekaran ◽

Nezih Altay ◽

Stephen J Childe ◽

Thanos Papadopoulos

Keyword(s):

Employee Turnover ◽

Factor Loading ◽

Personal Factors ◽

Related Factors ◽

Content Type ◽

Factors Affecting ◽

Work Related ◽

Humanitarian Organizations ◽

Using Data ◽

High Level

Purpose – At a time when the number and seriousness of disasters seems to be increasing, humanitarian organizations find that besides their challenging work they are faced with problems caused by a high level of turnover of staff. The paper aims to discuss these issues. Design/methodology/approach – Based on the 24 variables leading to employee turnover identified by Cotton and Tuttle (1986) the authors analyse the work-related, external and personal factors affecting employee turnover in humanitarian organizations, using a survey of members of the Indian National Institute of Disaster Management. Findings – Results indicated that the three factors are present. Of the external factors, only employment perception had a factor loading over 0.7; of the work-related factors, all were significant; of the personal factors, biographical information, marital status, number of dependants, aptitude and ability and intelligence had the highest loadings. It was also shown that behavioural intentions and net expectation were not significant. Originality/value – Only a few studies reported on employee turnover and its reasons are not well understood in the context of humanitarian organizations. To address this need, the aim of this paper is to explore the personal reasons impacting employee turnover in humanitarian organizations. In the study the authors have adopted 24 variables used in Cotton and Tuttle (1986) and classified into constructs to explain turnover, and further tested the model using data gathered from humanitarian organizations.

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Somaclonal variation on in vitro callus culture potato cultivars

Horticultura Brasileira ◽

10.1590/s0102-05362004000200027 ◽

2004 ◽

Vol 22 (2) ◽

pp. 300-304 ◽

Cited By ~ 28

Author(s):

Patricia N. Bordallo ◽

Derly H. Silva ◽

José Maria ◽

Cosme D. Cruz ◽

Elizabeth P. Fontes

Keyword(s):

Somaclonal Variation ◽

Culture Media ◽

Callus Formation ◽

Potato Cultivars ◽

Synthetic Seed ◽

Arbitrary Sequence ◽

Stem Explants ◽

Factors Affecting ◽

High Level

Synthetic seeds can be an alternative for those species in which botanical seeds are not viable. One of the major problems of in vitro plant cultivation is the high level of somaclonal variation. The most common factors affecting somaclonal variation are genotype, explant source, in vitro period and cultivation conditions in which the culture is established. In this work, calli were induced using leaf and stem explants of the commercial potato cultivars Achat, Baraka, Baronesa, Bintje, and Contenda in MS culture media supplemented with 1.65 mM of picloram and 11.5 mM of 2,4-D. Seventy and 90 days after induction, DNA samples of 40 calli were compared concerning the effects of the two explant (leaf and stem) and two growth regulator sources on five potatoes cultivars. A total of 20 arbitrary sequence primers were evaluated. The RAPD pattern generated by these primers suggested a high percentage of polymorphic fragments among the five genotypes, indicating a high level of genetic variation among cultivars. Cultivar Baronesa showed the highest number of polymorphic fragments for all treatments. The cultivar Contenda showed the smallest somaclonal variation, for most of the treatments, except for the treatment which consisted of stem explants, picloram (1.65 mM) application, and a 70-day period of callus formation. 'Contenda' is, therefore, the most suitable cultivar for synthetic seed production.

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Two methods of assessing the mortality factors affecting the larvae and pupae of Cameraria ohridella in the leaves of Aesculus hippocastanum in Switzerland and Bulgaria

Bulletin of Entomological Research ◽

10.1017/s0007485307005111 ◽

2007 ◽

Vol 97 (5) ◽

pp. 445-453 ◽

Cited By ~ 17

Author(s):

S. Girardoz ◽

R. Tomov ◽

R. Eschen ◽

D.L.J. Quicke ◽

M. Kenis

Keyword(s):

Leaf Senescence ◽

Sampling Method ◽

Plant Defence ◽

Leaf Miner ◽

Mortality Factor ◽

Horse Chestnut ◽

Mortality Factors ◽

Grab Sampling ◽

Defence Reaction ◽

Factors Affecting

AbstractThe horse-chestnut leaf miner, Cameraria ohridella, is an invasive alien species defoliating horse-chestnut, a popular ornamental tree in Europe. This paper presents quantitative data on mortality factors affecting larvae and pupae of the leaf miner in Switzerland and Bulgaria, both in urban and forest environments. Two sampling methods were used and compared: a cohort method, consisting of the surveying of pre-selected mines throughout their development, and a grab sampling method, consisting of single sets of leaves collected and dissected at regular intervals. The total mortality per generation varied between 14 and 99%. Mortality was caused by a variety of factors, including parasitism, host feeding, predation by birds and arthropods, plant defence reaction, leaf senescence, intra-specific competition and inter-specific competition with a fungal disease. Significant interactions were found between mortality factors and sampling methods, countries, environments and generation. No mortality factor was dominant throughout the sites, generations and methods tested. Plant defence reactions constituted the main mortality factor for the first two larval stages, whereas predation by birds and arthropods and parasitism were more important in older larvae and pupae. Mortality caused by leaf senescence was often the dominant mortality factor in the last annual generation. The cohort method detected higher mortality rates than the grab sampling method. In particular, mortality by plant defence reaction and leaf senescence were better assessed using the cohort method, which is, therefore, recommended for life table studies on leaf miners.

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Changes in levels of foliar carbohydrates and myo-inositol before premature leaf senescence of Populus nigra induced by a mixture of O3 and SO2

Canadian Journal of Botany ◽

10.1139/b96-120 ◽

1996 ◽

Vol 74 (6) ◽

pp. 965-970 ◽

Cited By ~ 11

Author(s):

R. C. Fialho ◽

J. Bücker

Keyword(s):

Air Pollution ◽

Leaf Senescence ◽

Populus Nigra ◽

Continuous Exposure ◽

Nonstructural Carbohydrates ◽

Progressive Decline ◽

Total Nonstructural Carbohydrates ◽

Leaf Yellowing ◽

Premature Leaf Senescence ◽

Early Indication

Specimens of Populus nigra L. cv. Loenen exhibit premature leaf senescence when exposed for a few weeks to realistic air pollution. In this study, the changes in levels of foliar carbohydrates and myo-inositol (MI) due to 30 ± 1 nL/L O3 + 12 ± 1 nL/L SO2 from the onset of exposure to the occurrence of premature abscission is presented. Petioles and laminae of the 12 oldest leaves were separately analysed on days 0, 4, 8, 12, 16, 20, 22, and 32 of continuous exposure, which was performed in open-top chambers (OTC). On days 8 to 12, clearly prior to yellowing (starting on day 22), total nonstructural carbohydrates (TNC; starch + raffinose + sucrose + glucose + fructose + MI) in the fumigated laminae exceeded that in controls by about 30%. This increase was due to higher amounts of different soluble forms, while starch remained unaltered. From day 20 onwards, the level of TNC in the fumigated laminae progressively fell below that in controls. This decrease was due to a progressive decline in starch, which had started on day 16 and was dominating, although glucose and raffinose increased significantly. In the petioles, starch, sucrose, and glucose decreased because of fumigation with the occurrence of leaf yellowing, while raffinose increased. In contrast, MI in the petioles progressively accumulated directly on exposure until leaf yellowing occurred. The results are discussed in terms of the "general adaption syndrome" of H. Selye (1936. Nature (London), 138: 32). The marked MI response in petioles is concluded to be an early indication of phytorelevant O3 + SO2 pollution. Keywords: air pollution, carbohydrates, myo-inositol, pigments, Populus nigra L., senescence, stress.

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INHERITANCE OF RESISTANCE TO NET BLOTCH IN BARLEY. I. FACTORS AFFECTING THE PENETRANCE AND EXPRESSIVITY OF GENE(S) CONDITIONING HOST RESISTANCE

Canadian Journal of Genetics and Cytology ◽

10.1139/g69-068 ◽

1969 ◽

Vol 11 (3) ◽

pp. 587-591 ◽

Cited By ~ 10

Author(s):

T. N. Khan

Keyword(s):

Environmental Conditions ◽

Net Blotch ◽

Host Reaction ◽

Susceptible Parent ◽

Breeding Programs ◽

Genetic Studies ◽

Factors Affecting ◽

Drechslera Teres ◽

Resistant Varieties ◽

High Level

Variability in the host-reaction of barley to infection by Drechslera teres was examined in the parents and progeny of selected crosses under different environmental conditions of testing.The Ethiopian variety C.I. 5791 exhibits a consistently high level of resistance under a range of environmental conditions, which is in contrast to the Manchurian variety C.I. 2330. The sensitivity of the genes for resistance possessed by these varieties to environmental modifications is considered to depend upon their respective genetic backgrounds. Furthermore, variability of host reaction in the progeny of these resistant varieties was shown to be influenced by the genetic background of the susceptible parent used.The implications of these findings in the conduct and interpretation of genetic studies and in backcross breeding programs is discussed.

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