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Processes in the leaf apoplast are relevant for development, cell wall rheological properties, plant nutrition, sink-source portioning, microbe-host plant-interactions or intercellular information exchange and signaling and are therefore regulated or influenced by the composition of the leaf apoplastic solute.In contrast to the traditional methods for the extraction of apoplastic solutes that are more or less destructive, we propose a new method that allows extraction of leaf apoplastic solutes (i) non-invasively and, thus, (ii) over time. Moreover, the method has (iii) a high spatial resolution that allows identification of solute-microdomains in the leaf apoplast. The method was established forArabidopsis thalianaandVicia fabaleaves but should also be applicable to other plants species with similar leaf morphologies. It is based on the infiltration of an aqueous extraction solution into the apoplast followed by its recovery seconds later, both through the stomata. By this, the apoplast (and its solutes) of an identical leaf can be sampled on successive days with negligible symplastic contamination.A spatiotemporal mapping of leaf apoplastic ion and metabolite patterns within the identical leaf opens a window of opportunity for understanding apoplast biology. As for example, the existence of apoplastic abscisic acid gradients within a leaf in response to salinity was witnessed in this study, as was the unsuspected accumulation of kaempferol glycosides in the leaf apoplast.The presented method is relevant for plant developmental biologists, phytopathologists, plant physiologists, plant nutritionists and others that need to integrate apoplast biology into their research approaches.

Background: Tenofovir disoproxil fumarate (TDF) is associated with adverse renal outcomes when prescribed for HIV infection. There are few data concerning real-world renal outcomes amongst patients prescribed TDF for pre-exposure prophylaxis (PrEP). Methods and findings: Data were extracted from 52 sexual health clinics across Australia from 2009–2019. All patients prescribed TDF-containing antiretroviral therapy and PrEP were included. Rates of renal impairment (a fall in eGFR to

Chloride (Cl−) is required for photosynthesis and regulates osmotic balance. However, excess Cl− application negatively interacts with nitrate ($${\mathrm{NO}}_{3}^{-}$$ NO 3 - ) uptake, although its effect on $${\mathrm{NO}}_{3}^{-}$$ NO 3 - metabolism remains unclear. The aim was to test whether Cl− stress disturbs nitrate reductase activity (NRA). A maize variety (Zea mays L. cv. LG 30215) was hydroponically cultured in a greenhouse under the following conditions: control (2 mM CaCl2), moderate Cl− (10 mM CaCl2), high Cl− (60 mM CaCl2). To substantiate the effect of Cl− stress further, an osmotic stress with lower intensity was induced by 60 g polyethylene glycol (PEG) 6000 L−1 + 2 mM CaCl2), which was 57% of the osmotic pressure being produced by 60 mM CaCl2. Results show that high Cl− and PEG-induced osmotic stress significantly reduced shoot biomass, stomatal conductance and transpiration rate, but NRA was only decreased by high Cl− stress. The interference of NRA in chloride-stressed maize is supposed to be primarily caused by the antagonistic uptake of Cl− and $${\mathrm{NO}}_{3}^{-}$$ NO 3 - .

This paper highlights the main elements of a doctoral research regarding the efficiency of workers evaluation process in the workplace. Based on the global competition, organizations are in continuous quality improvement of their processes to stay competitive. The focus is on motivating and constantly offering constructive feedback to the employees by evaluating them on the following criteria: job description requirements, operational objectives and behavioral objectives. The aim of this study is to confirm that in the context of digitization, both evaluation based on objectives and 360-degree evaluation have its advantages and disadvantages and to analyze the impact of it in organization’s performance. Since this process is divided in two parts (mid-year review and final review), an interesting research question would be how useful is to offer feedback to employees at the middle of the evaluation period and its impact on the final review. The first part of the paper will focus on defining the evaluation process and its scope, pursue by an analysis of 360-degree evaluation, evaluation based on objectives, and the evaluation process in the digital era. It would be a challenge to discover the inclination of organizations for different types of evaluations as well as perception differences between employees and employers. Many researches consider that one of the used methods implemented in companies is the evaluation based on objectives. A larger documentation on this subject would delimit the types of evaluations to help companies to easily choose the type that fits its culture. For this purpose, we will perform an outline on the existing literature by analyzing authors’ opinions on this subject and identifying advantages and disadvantages of the two types of evaluation specified above.

Onions (Allium cepa L.) are considered a salt-sensitive crop. However, to date, little evidence supports this claim and information about the physiological and metabolomic effects of Na+ accumulation in onion plants is lacking. The purpose of our research has been to assess changes in onion bulbs of three different cultivars after soil and foliar applications with moderate doses of chloride-free Na2SO4. The antioxidative defense mechanism in onion and the accumulation of Na+ within the plant has also been analyzed. Based on Na+ leaf and bulb concentrations, our findings demonstrate that Na+ is only transported from bulbs to leaves not vice versa, therefore foliar application does not lead to Na+ accumulation in the bulbs. Soil application with Na2SO4 results in an accumulation of Na+ in the leaves and bulbs, but with the exception of one onion variety this accumulation does not alter the metabolite profile of onions significantly. Even the K+ concentration and organic solute levels are unchanged after accumulation of Na+. Nevertheless, after Na2SO4 treatment, the antioxidative defense system moderately increases in onion bulbs. This study demonstrates that onion plants have the ability to exclude Na+ at moderate Na2SO4 treatment, and that the potential for quality onion production in soils with increased sodium concentration is much higher than previously assumed.

Maize is the most important crop worldwide in terms of production and yield, but every year a considerable amount of yield is lost due to drought. The foreseen increase in the number of drought spells due to climate change raises the question whether the ability to recover quickly after a water pulse may be a relevant trait for overall drought resistance. We here address the following hypotheses: (i) different maize hybrids exhibit distinct physiological adaptive responses to drought stress and (ii) these responses affect the ability to recover from the stress. (iii) The relative biomass production of maize hybrids, which show severe drought symptoms but are able to recover quickly after a water pulse, is comparable to those hybrids, which invest more energy into tolerance mechanisms. The physiological responses of eight maize hybrids to repeated drought were elucidated employing physiological parameters such as electrolyte leakage, osmolality, relative water content, growth rate and gas-exchange measurements. Only one hybrid was able to maintain biomass production under drought conditions. Amongst the others, two hybrids with similar growth inhibition but contrasting physiological responses were identified by a PCA analysis. Both strategies, i.e. stabilization of leaf water content via resistance mechanisms versus high recovery potential were equally effective in maintaining aboveground biomass production in the scenario of a long drought intermitted by a water-pulse. However, each strategy might be advantageous under different drought stress scenarios. Overall, the recovery potential is underestimated in drought resistance under natural conditions, which includes periodic cycles of drought and rewatering, and should be considered in screening trials.

Objectives Bacterial contamination of breast implants and biofilm formation has been discussed as a major reason for implant loss and capsular contraction. Intra- and perioperative treatment of breast implants with disinfectants to prevent bacterial contamination has been frequently reported. Given the increasing awareness of concerns about product liability the question of whether short-time irrigation of implants with antimicrobial substances during the operative procedure would potentially alter the integrity of the implant shell has attracted legal and medical interest. In this study we therefore investigated whether irrigating breast implants with antimicrobials commonly used in clinical practice with a clinically relevant application time would affect the physical integrity of the implant shell. Materials and methods Samples, which were previously punched from the shell of explanted standard silicone gel filled breast implants in a defined way, were exposed to different disinfectant solutions for two minutes. Multiple defined specimens from 5 different explants from 4 different producers (including PIP) were tested. The testing included tensile strength and disruption tests. Results In our prospective test series we could not find a significant influence of a single distinct disinfectant on silicone shell implant surfaces. Conclusion Despite the potential legal implications that might be considered when a surgeon manipulates an implant with disinfectants intraoperatively, we find it worthwhile to state that from a material and surgical standpoint there is no evidence that short-time treatment of alloplastic materials would be detrimental to the physical properties of the implant shell.