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991.
Jana Pospíšilová 《Biologia Plantarum》1975,17(6):392-399
The mutual relationship between the water potential (γ w ), its components, namely the osmotic potential (γ s ) and the pressure potential (γ p ), and the water saturation deficit (ΔW sat ) were determined in the leaves of different insertion levels. During the water stress development in kale plants induced by decreasing soil moisture theγ w decreased, parallely in all the leaves but the same decrease ofγ q was accompanied by the highest decrease of theγ p , probably due to the accumulation of osmotically active solutes, and the lowest decrease ofγ p in the upper leaves and with the lowest decrease ofγ s and the highest decrease ofγ p in the lower leaves. Also the corresponding values of the ΔW sat were always lower in the upper than in the middle and lower leaves. Thus the upper leaves wilted at more negative values ofγ w than the other leaves. On the contrary, during the wilting of the cut off leaves the relationship betweenγ w and ΔW sat in the upper, middle and lower leaves was practically the same. The very slightly higher decrease ofγ s in the upper leaves in comparison with the other leaves was compensated by a lower deerease of theirγ p . These changes in the ratios ofγ w ,γ s ,γ p and ΔW sat with the leaf insertion levels enabled the preference of the upper leaves in retaining the necessary water supply during the wilting of plantsin situ. 相似文献
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993.
Lenice de Castro Muniz de Quadros Luciana de Avila Quevedo Janaína Vieira dos Santos Motta André Carraro Felipe Garcia Ribeiro Bernardo Lessa Horta Denise Petrucci Gigante 《PloS one》2015,10(10)
This study aimed to evaluate the relationship between mental disorders at 30 years of age and social mobility by formally testing three hypotheses: Risk Accumulation; Critical Period; and Social Mobility. The study was performed using data from the 30-year follow-up of the Pelotas Birth Cohort Study, conducted in 1982, and data from previous follow-ups. The tool used to evaluate mental health was the Self Report Questionnaire (SRQ-20). For the statistical analysis, the chi-square test with the Yates correction was used to estimate the prevalence of mental disorder, and the Poisson regression with robust variance was used to formally test the hypotheses according to the Risk Accumulation, Critical Period and Social Mobility Models. The analyses were stratified by gender. The prevalence of Common Mental Disorders (CMDs) was 24.3% (95% CI 22.9–25.7) when the whole sample was considered. The highest prevalence, 27.1% (95% CI 25.1–29.2), was found in women, and the difference between genders was significant (p < 0.001). CMDs were more frequent in participants who remained “poor” in the three follow-ups. In both men and women, the best fit was obtained with the Risk Accumulation Model, with p = 0.6348 and p = 0.2105, respectively. The results indicate the need to rethink public income maintenance policies. Finally, we suggest further studies to investigate the role of different public policies in decreasing the prevalence of mental disorders and thus contribute proposals of new policies that may contribute to the prevention of these disorders. 相似文献
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995.
996.
Abha Saxena Suryateja Ravutla Vikas Upadhyay Soumya Jana David Murhammer Lopamudra Giri 《Biotechnology and bioengineering》2020,117(5):1483-1501
Packaging during the passaging of viruses in cell cultures yields various phenotypes and is regulated by viral protein expression in infected cells. Although such a packaging mechanism has a profound effect in controlling the virus yield, little is known about the underlying statistical models followed by virus packaging and protein expression among cells infected with the virus. A predictive framework combining identification of the probability density function (PDF) based on log-likelihood and using the PDF for Monte-Carlo simulations is developed. The Birnbaum–Saunders distribution was found to be consistent with all three-virus packaging levels, including nucleocapsids/occlusion-derived virus (ODV), ODVs/polyhedra, and polyhedra/cell for both wild-type and genetically modified AcMNPV. Next, it was demonstrated that PDF fitting could be used to compare two viruses having distinctly different genetic configurations. Finally, the identified PDF can be incorporated in RNA synthesis parameters for baculovirus infection to predict the cell-to-cell variability in protein expression using Monte-Carlo simulations. The proposed tool can be used for the estimation of uncertainty in the kinetic parameter and prediction of cell-to-cell variability for other biological systems. 相似文献
997.
Janeczko Anna Biesaga-Kościelniak Jolanta Dziurka Michał Filek Maria Hura Katarzyna Jurczyk Barbara Kula Monika Oklestkova Jana Novak Ondrej Rudolphi-Skórska Elżbieta Skoczowski Andrzej 《Journal of Plant Growth Regulation》2020,39(1):507-507
Journal of Plant Growth Regulation - The original version of this article unfortunately contained an error in Dr. Andrzej Skoczowski’s affiliation. The author would like to correct the error... 相似文献
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999.
The biosynthesis of xanthan by Xanthomonas campestris was found to be affected by the addition of citric acid in fed batch mode. Under oxygen-limiting conditions, the addition of up to 2.6 g citric acid per litre improved cell viability as well as increasing xanthan yield by up to 80%. Comparative xanthan formation profiles at different operating conditions indicate that at higher aeration (when there was no oxygen limitation), citric acid addition did not improve xanthan production. 相似文献
1000.
Jana Schmuch Sabine Beckert Simone Brandt Gesine L?hr Fabian Hermann Thomas J. Schmidt Thomas Beikler Andreas Hensel 《PloS one》2015,10(3)