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Iron (Fe) is an essential plant micronutrient, being a major limiting growth factor in calcareous soils. To increase Fe uptake, plants induce lateral roots growth, the expression of a Fe(III)-chelate reductase (FCR), a Fe(II)-transporter and a H+-ATPase and the secretion of flavins. Furthermore, auxin hormone family is involved in the Fe-deficiency responses but the action mechanism remains elusive. In this work, we evaluated the effect of the auxin-precursor indole-3-acetaldoxime (IAOx) on hydroponically grown Medicago truncatula plants under different Fe conditions. Upon 4-days of Fe starvation, the pH of the nutrient solution decreased, while both the FCR activity and the presence of flavins increased. Exogenous IAOx increased lateral roots growth contributing to superroot phenotype, decreased chlorosis, and delayed up to 3-days the pH-decrease, the FCR-activity increase, and the presence of flavins, compared to Fe-deficient plants. Gene expression levels were in concordance with the physiological responses. showed that IAOx was immediately transformed to IAN in roots and shoots to maintain auxin homeostasis. IAOx plays an active role in iron homeostasis delaying symptoms and responses in Fe-deficient plants. We may speculate that IAOx or its derivatives remobilize Fe from root cells to alleviate Fe-deficiency. Overall, these results point out that the IAOx-derived phenotype may have advantages to overcome nutritional stresses. • The superroot phenotype in IAOx-treated Medicago plants may improve iron nutrition. • IAOx plays an active role in iron homeostasis delaying symptoms and responses in Fe-deficient plants. • IAOx or its derivatives in a synergistic mechanism may well remobilize Fe from root cells to alleviate Fe-chlorosis. [ABSTRACT FROM AUTHOR]

The Central and Eastern European countries have experienced significant imbalances starting with 2008 that have affected their business environment profoundly. Thus, the firms operating in the region have faced, and continue to face, difficulties and major challenges. Through this paper we aim at analyzing the key indicators that characterize the business environment of a country, and by analyzing their values through time, we want to compare the situation from ten countries from CEE. We analyzed the indicators for a period of eight years, between 2007 and 2014. This period presents interest because it comprises the period of the recent financial crisis. By using indicators characterizing the business environment we analyze the ease of doing business, but also the ease of getting credit, domestic credit to private sector and reforms adopted in order to improve the access to credit by the CEE countries. We also analyze the time needed to start a business and the regulations regarding start-ups, which may encourage or discourage the new firms to enter the market. The results obtained show that the CEE countries are starting to recover from the current financial crisis, but are still lagging behind the developed countries of the European Union. However, the business environment has registered a series of improvements in the majority of the analyzed countries in the last two years, improving especially the areas of starting a business, getting a credit and paying taxes. [ABSTRACT FROM AUTHOR]

Two studies of the Effort–Reward Imbalance (ERI) model of work stress with different end points were undertaken in community samples from the Adelaide (Australia) metropolitan area. Study 1 examined the relationship between ERI at work and state anger. Study 2 extended the first and examined the relationship between ERI, anger and cardiovascular disease (CVD) symptoms. Hierarchical multiple regression confirmed a significant relationship between ERI and state anger in Study 1 even after controlling for extraneous variables. Study 2 showed that ERI increases CVD symptoms via the mediating variable of anger (an indirect effect). Furthermore, Study 2 revealed that people of lower income were more likely to experience higher anger. The results of both studies have far ranging consequences for the emotional and physical health of individuals who are experiencing an imbalance between their efforts and perceived rewards at work and those with lower incomes may be more vulnerable. The wider public health implications of the relationship between work stress, and emotional and physical well being in the community are discussed. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The increase in O2 tension after birth is a major factor stimulating ductus arteriosus (DA) constriction and closure. Here we. studied the role of the mitochondrial electron transport chain (ETC) as sensor, H2O2 as mediator, and voltage-gated potassium (Ky) channels and Rho kinase as effectors of O2-induced contraction in the chicken DA during fetal development. Switching from 0% to 21% O2 contracted the pulmonary side of the mature DA (mature pDA) but had no effect in immature pDA and relaxed the aortic side of the mature DA (mature aDA). This contraction of the pDA was attenuated by inhibitors of the mitochondrial ETC and by the H2O2 scavenger polyethylene glycol (PEG)-catalase. Moreover, O2 increased reactive oxygen species (ROS) production, measured with the fluorescent probes dihydroethidium and 2',7'-dichlorofluorescein, only in mature pDA. The H2O2 analog t-butyl-hydroperoxide mimicked the responses to O2 in the three vessels. In contrast to immature pDA cells, mature pDA cells exhibited high-amplitude O2-sensitive potassium currents. The Kv channel blocker 4-aminopyridine prevented the current inhibition elicited by O2. The L-type Ca2+ (CaL) channel blocker nifedipine and the Rho kinase inhibitors Y-27632 and hydroxyfasudil induced a similar relaxation when mature pDA were stimulated with O2 or H2O2. Moreover, the sensitivity to these drugs increased with maturation. Our results indicate the presence of a common mechanism for O2 sensing/signaling in mammalian and nonmammalian DA and favor the idea that, rather than a single mechanism, a parallel maturation of the sensor and effectors is critical for O2 sensitivity appearance during development. [ABSTRACT FROM AUTHOR]