scholarly journals Results of the Biochemical Study of Mandarin (Citrus reticulata Blanco) Mutants

Author(s):  
G.R. Memarne ◽  
N.I. Khalvashi ◽  
M.T. Gabaidze ◽  
D. Sh. Baratashvili ◽  
A.R. Kalandia ◽  
...  

Background: Induced mutagenesis has been used in citrus breeding, in Georgia, since 1960, resulting in many interesting and promising mutant forms that require morphological, physiological and biochemical studies. The present paper presents the results of biochemical research of some promising mutants. Methods: During the period 2017-2019 investigate on 13 promising mutant forms of mandarin has been carried out. In the current study, phenolic composition content in the fruits of mandarin mutants were determined using Ultraviolet Spectrophotometer and High Performance Liquid Chromatography (HPLC) and their antioxidant capacities were evaluated using 2.2-diphenyl-1-picrylhydrazyl (DPPH) radicals.Result: The results have shown that different concentrations of mutagen effect on mandarin seeds and, accordingly, on the biochemical components which they include. In most cases, this leads to a positive result. The impact of the mutagen significantly increases the range of changes in biochemical components and varies over a wide range. Analyzing the data, we can conclude that the solutions of all concentrations of the Nash mutagen effect a change in the biochemical indicators in mutant forms. However, a wide range of variability is largely associated with the use of medium and low concentrations of the mutagen. In most cases, the majority of mutant forms significantly outperform the control variants in the content of biochemical components. The study has revealed a variety of mutant forms (gene pool), which characterized a whole complex of positive signs. Their use in selection allows getting perspective forms with positive features.

2016 ◽  
Vol 24 (3) ◽  
pp. 318-334 ◽  
Author(s):  
Jie Li ◽  
Stacie Furst-Holloway ◽  
Larry Gales ◽  
Suzanne S. Masterson ◽  
Brian D. Blume

This study investigates how each dimension of transformational leadership directly and indirectly influences followers’ change-oriented behaviors. Using a sample of 329 independent leader–follower dyads from a wide range of Chinese organizations, we examine followers’ identification with leader as an intervening variable between the four dimensions of transformational leadership (“core” transformational behaviors, high-performance expectations, individualized support, and intellectual stimulation) and followers’ taking charge behaviors. Results showed that intellectual stimulation had the highest relative effect size that was largely due to its direct effect on taking charge. Individualized support only exerted a significant indirect effect. Additionally, the negative direct and positive indirect effects of high-performance expectations rendered its total effect nonsignificant. Furthermore, the direct, indirect, and total effects of “core” transformational behaviors were nonsignificant. We also found that followers’ value of modernity moderated the effect of identification with leader on taking charge. The indirect effects of intellectual stimulation, individualized support, and high-performance expectations were significant when modernity was high but nonsignificant when it was low. Implications for theory, practice, and future research are discussed.


2020 ◽  
Vol 10 (16) ◽  
pp. 5556
Author(s):  
Torsten Fischer ◽  
Bernd Kuhn ◽  
Detlef Rieck ◽  
Axel Schulz ◽  
Ralf Trieglaff ◽  
...  

Strong efforts are made internationally to optimize the process control of laser additive manufacturing processes. For this purpose, advanced detectors and monitoring software are being developed to control the quality of production. However, commercial suppliers of metal powders and part manufacturers are essentially focused on well-established materials. This article demonstrates the potential of optimized process control. Furthermore, we outline the development of a new high temperature structural steel, tailored to best utilize the advantages of additive manufacturing techniques. In this context, the impact of production-induced porosity on fatigue strength of austenitic 316L is presented. Additionally, we discuss the first conceptual results of a novel ferritic steel, named HiperFer (High Performance Ferrite), which was designed for increased fatigue strength. This ferritic, Laves phase-strengthened, stainless steel could be used for a wide range of structural components in power and (petro)chemical engineering at maximum temperatures ranging from about 580 to 650 °C. This material benefits from in situ heat treatment and counteracts process-related defects by “reactive” crack obstruction mechanisms, hampering both crack initiation and crack propagation. In this way, increased fatigue resistance and safety can be achieved.


2021 ◽  
Author(s):  
Aruna Kumari Neelam ◽  
Prithvi P

Abstract Nanosheet Field Effect Transistor (NSFET) is a viable contender for future scaling in sub-7-nm technology. This paper provides insights into the variations of DC FOMs for different geometrical configurations of the NSFET. In this script, DC performance of 3D GAA NSFET is analyzed by varying the width, thickness of the device. Moreover, the gate length is scaled from 20 nm to 5 nm to check for the device suitability in logic applications. The thickness and width of each nanosheet are varied in the range of 5 to 9 nm, and 10 to 50 nm respectively to analyse the performance dependency on the geometry of the device. The impact of geometry of NSFET on various DC performance metrics like transfer characteristics, sub-threshold swing (SS), on current (ION), off current (IOFF), switching ratio (ION/IOFF), threshold voltage (Vth) and drain induced barrier lowering (DIBL) are studied. On top of that, the device’s electrical characteristics are analyzed for a wide range of temperatures from -43oC to 127oC to identify the temperature compensation point and is observed at VGS = 0.55 V and ID = 3.86 × 10−6 A. Furthermore, the important process parameter, work function variations on transfer characteristics of the device is analyzed. Moreover, the analyses tell that, for sub -7 nm, the NSFET is a potential device for high performance and good logic applications.


2021 ◽  
Author(s):  
Cristina López-Duarte ◽  
Jane F. Maley ◽  
Marta M. Vidal-Suárez

AbstractThis study analyses international student mobility (ISM) in Europe since the 1999 Bologna Declaration. International mobility of higher education students is both a driver and a consequence of the Bologna Process and emerges as a relevant issue in a wide range of research areas. This literature review develops a qualitative content analysis of the set of high-performance articles published between 2000 and 2018 and identified through a wide range of bibliometric tools: direct (first generation) citation counts; indirect or accumulated impact; early influence; adjusted impact with respect to year of publication, type of document, and discipline; and alternative metrics that measure interactions in the internet and social media. The content analysis focuses on the pending achievements and main challenges to ISM, among them: attracting non-European students to whole degree programs, the need for actual and further convergence in programs and systems to ensure real compatibility, the impact of HE ISM on the promotion of the European citizenship and consciousness, the sharp imbalance between credit and degree mobility, the need to strengthen the link between ISM and employability, the existing social selectivity in European ISM, the frequent social segregation problems faced by international students.


1992 ◽  
Vol 10 (2) ◽  
pp. 304-310 ◽  
Author(s):  
C K Osborne ◽  
V J Wiebe ◽  
W L McGuire ◽  
D R Ciocca ◽  
M W DeGregorio

PURPOSE The antiestrogen tamoxifen is effective in therapy for breast cancer. However, its use is limited by the eventual development of acquired tamoxifen resistance in many patients. The mechanisms responsible for tamoxifen resistance remain unknown; loss of estrogen receptor (ER), selection of hormone-independent breast cancer clones, or alterations in serum tamoxifen levels after long-term use do not explain acquired resistance in most patients. Using an experimental model in which human breast cancer cells develop resistance in athymic mice treated with tamoxifen, we have recently shown that acquired resistance is associated with markedly reduced cellular concentrations of tamoxifen and by isomerization of the trans-4-hydroxy metabolite to the less potent cis isomer. MATERIALS AND METHODS Using a sensitive high-performance liquid chromatography (HPLC) assay, we have now measured levels of tamoxifen and its major metabolites in a series of 14 tumors from patients treated with tamoxifen. The duration of therapy ranged from 1 month to 6 years. RESULTS Tumor tamoxifen levels varied over a wide range. Low concentrations were observed in tumors from eight patients, all demonstrating progressive disease at the time of biopsy after a minimum duration of treatment of 6 months. Six tumors had moderate to high tamoxifen levels, two from patients responding to tamoxifen, one from a patient with stable disease, and three from patients with disease progression. Both the cis and trans isomers of the potent antiestrogenic metabolite 4-hydroxy-tamoxifen were detected in 11 tumors. Six tumors had high ratios of the cis to trans isomer (1.10:2.06), all from patients not responding to tamoxifen. The five tumors with low cis:trans ratios included the two tumors from responding patients and three from patients with progression. All but one of the 11 nonresponding patients had either a low tumor tamoxifen level, a high cis:trans ratio, or both. CONCLUSION This study clearly demonstrates a wide range of tumor tamoxifen levels and accumulation of the less antiestrogenic cis isomer of 4-hydroxytamoxifen in some patients on tamoxifen therapy. Additional study is necessary to determine if these metabolic profiles are related to the development of tamoxifen resistance.


2021 ◽  
Vol 9 ◽  
Author(s):  
Ying Chen ◽  
Jian Guo ◽  
Shipei Xing ◽  
Huaxu Yu ◽  
Tao Huan

Hair is a unique biological matrix that adsorbs short-term exposures (e. g., environmental contaminants and personal care products) on its surface and also embeds endogenous metabolites and long-term exposures in its matrix. In this work, we developed an untargeted metabolomics workflow to profile both temporal exposure chemicals and endogenous metabolites in the same hair sample. This analytical workflow begins with the extraction of short-term exposures from hair surfaces through washing. Further development of mechanical homogenization extracts endogenous metabolites and long-term exposures from the cleaned hair. Both solutions of hair wash and hair extract were analyzed using ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS)-based metabolomics for global-scale metabolic profiling. After analysis, raw data were processed using bioinformatic programs recently developed specifically for exposome research. Using optimized experimental conditions, we detected a total of 10,005 and 9,584 metabolic features from hair wash and extraction samples, respectively. Among them, 274 and 276 features can be definitively confirmed by MS2 spectral matching against spectral library, and an additional 3,356 and 3,079 features were tentatively confirmed as biotransformation metabolites. To demonstrate the performance of our hair metabolomics, we collected hair samples from three female volunteers and tested their hair metabolic changes before and after a 2-day exposure exercise. Our results show that 645 features from wash and 89 features from extract were significantly changed from the 2-day exposure. Altogether, this work provides a novel analytical approach to study the hair metabolome and exposome at a global scale, which can be implemented in a wide range of biological applications for a deeper understanding of the impact of environmental and genetic factors on human health.


1997 ◽  
Vol 77 (03) ◽  
pp. 504-509 ◽  
Author(s):  
Sarah L Booth ◽  
Jacqueline M Charnley ◽  
James A Sadowski ◽  
Edward Saltzman ◽  
Edwin G Bovill ◽  
...  

SummaryCase reports cited in Medline or Biological Abstracts (1966-1996) were reviewed to evaluate the impact of vitamin K1 dietary intake on the stability of anticoagulant control in patients using coumarin derivatives. Reported nutrient-drug interactions cannot always be explained by the vitamin K1 content of the food items. However, metabolic data indicate that a consistent dietary intake of vitamin K is important to attain a daily equilibrium in vitamin K status. We report a diet that provides a stable intake of vitamin K1, equivalent to the current U.S. Recommended Dietary Allowance, using food composition data derived from high-performance liquid chromatography. Inconsistencies in the published literature indicate that prospective clinical studies should be undertaken to clarify the putative dietary vitamin K1-coumarin interaction. The dietary guidelines reported here may be used in such studies.


2009 ◽  
Vol 8 (1) ◽  
Author(s):  
Chalimah .

eamwork is becoming increasingly important to wide range of operations. It applies to all levels of the company. It is just as important for top executives as it is to middle management, supervisors and shop floor workers. Poor teamwork at any level or between levels can seriously damage organizational effectiveness. The focus of this paper was therefore to examine whether leadership practices consist of team leader behavior, conflict resolution style and openness in communication significantly influenced the team member’s satisfaction in hotel industry. Result indicates that team leader behavior and the conflict resolution style significantly influenced team member satisfaction. It was surprising that openness in communication did not affect significantly to the team members’ satisfaction.


2021 ◽  
Author(s):  
Ekaterina Mosolova ◽  
Dmitry Sosin ◽  
Sergey Mosolov

During the COVID-19 pandemic, healthcare workers (HCWs) have been subject to increased workload while also exposed to many psychosocial stressors. In a systematic review we analyze the impact that the pandemic has had on HCWs mental state and associated risk factors. Most studies reported high levels of depression and anxiety among HCWs worldwide, however, due to a wide range of assessment tools, cut-off scores, and number of frontline participants in the studies, results were difficult to compare. Our study is based on two online surveys of 2195 HCWs from different regions of Russia during spring and autumn epidemic outbreaks revealed the rates of anxiety, stress, depression, emotional exhaustion and depersonalization and perceived stress as 32.3%, 31.1%, 45.5%, 74.2%, 37.7% ,67.8%, respectively. Moreover, 2.4% of HCWs reported suicidal thoughts. The most common risk factors include: female gender, nurse as an occupation, younger age, working for over 6 months, chronic diseases, smoking, high working demands, lack of personal protective equipment, low salary, lack of social support, isolation from families, the fear of relatives getting infected. These results demonstrate the need for urgent supportive programs for HCWs fighting COVID-19 that fall into higher risk factors groups.


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