The effect of drought and vapour pressure deficit on gas exchange of young kiwifruit (Actinidia deliciosa var. deliciosa) vines

To evaluate the effect of drought and vapour pressure deficit (VPD) on stomatal behaviour and gas exchange parameters, young kiwifruit vines (Actinidia deliciosa var. deliciosa cv. Hayward) were exposed to alternating periods of drought and drought-relief over two growing seasons. Vines were grown either in the field or in containers. Stomatal conductance of fully- expanded leaves rapidly decreased as pre-dawn leaf water potential was reduced below a threshold value of -0.3 MPa. Stomatal conductance reached minimum values of 10-20 mmol m-2 s-1. Transpiration rate was similarly sensitive to changes in leaf water status, whereas more severe drought levels were necessary to affect photosynthesis significantly. Net daily carbon gains were estimated at 4.7 and 2.7 g m-2 for irrigated and droughted vines, respectively. Gas exchange parameters recovered to values of irrigated vines within a few hours after relief of stress. Rate of recovery depended on the level of stress reached during the previous drought period. There was a steady decline in stomatal conductance when VPD was increased from 0.8 to 2.5 kPa in both irrigated and droughted vines. The VPD at which stomatal conductance reached 50% of maximum values was 2.1-2.2 kPa for both treatments. We conclude that stomata were highly sensitive to changes in soil water status and that midday depression of photosynthesis measured in kiwifruit vines was related to water deficits arising in the leaf because of both transpirational losses and to the direct effect of increasing VPD

Productivity and fruit quality of Vaccinium corymbosum cv. Elliott under photo-selective shading nets

Lobos, GA (Lobos, G. A.)[ 1 ] ; Retamales, JB (Retamales, J. B.)[ 1 ] ; Hancock, JF (Hancock, J. F.)[ 2 ] ; Flore, JA (Flore, J. A.)[ 2 ] ; Romero-Bravo, S (Romero-Bravo, S.)[ 1 ] ; del Pozo, A (del Pozo, A.)[ 1 ] 1 ] Univ Talca, Fac Ciencias Agr, Talca, ChileMichigan State Univ, Dept Hort, E Lansing, MI 48824 USAThe productivity and development of northern highbush blueberry plants (Vaccinum corymbosum L cv. Elliott) was examined under photo-selective nets of different colors (black, red and white) and shade intensities (25%, 50% and 75%) in Michigan-USA over two growing seasons. Photoselective nets influenced the photosynthetic active radiation (PAR) transmitted through the canopy, with white nets allowing significantly higher radiation to penetrate than red and black nets at all shade levels. After one year of treatment, the rate of flower bud development decreased linearly as % PAR increased, but the total number of flower buds per cane and terminal shoots increased gradually as light levels increased, reaching an asymptote at 50% PAR. The percentage of mature fruit on a particular date was higher in the control plants and decreased as the % PAR was reduced. The harvest delay was maximum at the lowest light level (20%) and decreased exponentially with increasing % PAR. Fruit soluble solids increased linearly (r(2) = 0.86; P < 0.0001) and fruit water content decreased linearly (r(2) = 0.88; P < 0.0001) as % PAR increased. Fruit yield showed a positive, curvilinear relationship With % PAR and reached an asymptote at 50% PAR. The interaction between color and shade was not significant. However, fruit quality (fruit weight, soluble solid and firmness) showed significant color x shade and color x harvest time (fruit weight, soluble solids and titratable acidity) interactions. Our results indicate that placing red and white nets over mature plants at intermediate shade levels (40-60% PAR) provide a harvest delay without detrimental effects on return bloom, yield or fruit quality. (C) 2013 Elsevier B.V. All rights reserved

Evaluatie van prestaties van de politie: Deel 2 van de evaluatie van de Politiewet 2012

Met de invoering van de Politiewet 2012 (Pw2012) wilde de minister van Veiligheid en Justitie (VenJ) zorgen voor een effectieve, efficiënte en maatschappelijk gewaardeerde politieorganisatie, die zowel rechtstatelijk als democratisch goed is ingebed.Artikel 74 van de Pw2012 bepaalt dat de minister van VenJ binnen vijf jaar na inwerkingtreding van de wet aan de Staten-Generaal een verslag dient te sturen over de doeltreffendheid en de effecten van de wet in de praktijk. Deze evaluatie wordt uitgevoerd in vier deelonderzoeken; het voorliggende onderzoek heeft betrekking op prestaties van de politie.De centrale vraag van het onderzoek ‘prestaties’ is of de keuze voor één politie met één beheerder tot betere prestaties van de politie heeft geleid. Om die vraag te beantwoorden is goed hanteerbare, geldige en betrouwbare informatie nodig over de prestaties van de nationale politie zoals beoogd en in praktijk gebracht met de inwerkingtreding van de Pw2012.Aangestuurd door een begeleidingscommissie hebben Berenschot en de TU Delft in de periode november 2016 – juni 2017 gezamenlijk onderzoek gedaan naar de vraag: Wat is de bijdrage van de Pw2012 aan het doelmatiger en slagvaardiger werken en beter presteren van de nationale politie

Evaluatie van prestaties van de politie: Deel 2 van de evaluatie van de Politiewet 2012

Met de invoering van de Politiewet 2012 (Pw2012) wilde de minister van Veiligheid en Justitie (VenJ) zorgen voor een effectieve, efficiënte en maatschappelijk gewaardeerde politieorganisatie, die zowel rechtstatelijk als democratisch goed is ingebed.Artikel 74 van de Pw2012 bepaalt dat de minister van VenJ binnen vijf jaar na inwerkingtreding van de wet aan de Staten-Generaal een verslag dient te sturen over de doeltreffendheid en de effecten van de wet in de praktijk. Deze evaluatie wordt uitgevoerd in vier deelonderzoeken; het voorliggende onderzoek heeft betrekking op prestaties van de politie.De centrale vraag van het onderzoek ‘prestaties’ is of de keuze voor één politie met één beheerder tot betere prestaties van de politie heeft geleid. Om die vraag te beantwoorden is goed hanteerbare, geldige en betrouwbare informatie nodig over de prestaties van de nationale politie zoals beoogd en in praktijk gebracht met de inwerkingtreding van de Pw2012.Aangestuurd door een begeleidingscommissie hebben Berenschot en de TU Delft in de periode november 2016 – juni 2017 gezamenlijk onderzoek gedaan naar de vraag: Wat is de bijdrage van de Pw2012 aan het doelmatiger en slagvaardiger werken en beter presteren van de nationale politie?Organisation and GovernanceMulti Actor System

Safe and effective cryopreservation methods for long-term storage of human-amniotic-fluid-derived stem cells

What's already known about this topic? Stem cells can be isolated from amniotic fluid and may be used for cell therapy and tissue engineering applications in perinatal medicine. Clinical implementation requires development of an adapted cell banking system including optimal processing and cryopreservation of amniotic fluid samples, with maintenance of cell viability and characteristics after thawing. What does this study add? We identified three suitable cryopreservation protocols of fresh amniotic fluid samples with high cell recovery rate and unchanged stem cell characteristics post-thawing. One of these is compatible with current good manufacturing practice legislation and can be performed in fetal medicine units without stem cell culture expertise. Objectives: Stem cells (SCs) can be isolated from amniotic fluid (AF) for a variety of perinatal applications. In view of this, we compared different cryopreservation protocols for these AFSCs. Methods: We screened seven freezing and thawing protocols using two well-established human AFSC lines: freezing protocol 1 (FP1), 10% dimethyl sulfoxide (DMSO); FP2, 2.5% DMSO, caspase inhibitor, and catalase; FP3, 5% glycerol, caspase inhibitor, and catalase; FP4, sperm freezing medium; FP5, slow-freezing solution; FP6, ethylene glycol, sucrose, and Ficoll 70; and FP7, vitrification solution. Outcome measures were post-thawing cell viability, recovery, doubling time and mesenchymal SC markers. The three best performing protocols were subsequently tested on cells isolated from clinical consecutive freshly harvested AF samples from two fetal medicine units. Results: Protocols 1, 5, and 6 performed significantly better on well-characterized cell lines. They performed equally well on cell pellets from freshly harvested AF (n=28). Conclusions: We identified three suitable cryopreservation protocols because of high cell recovery and unchanged SC characteristics. Given one of these, the slow-freezing solution, is compatible with current good manufacturing practice legislation, it may be ultimately clinically used.SCOPUS: ar.jFLWINinfo:eu-repo/semantics/publishe