Flavanols in grapevine: In vitro accumulation and defence reactions in shoots

Callus of two grapevine cultivars was cultivated for 4 weeks on MS-medium, half strength, which was additionally supplemented with abscisic acid (ABA), (+)-catechin or a combination of both. (+)-Catechin did not elevate the pool size of the callus flavanols. Application of 3 % sucrose caused a significant increase of the callus flavanols, whereas the response to ABA was quite variable. Leaves and shoots of cv. Spatburgunder (Pinot noir) were examined histologically on the mode of flavanol deposition. The flavanols of the leaf mesophyll were spread evenly throughout the central vacuole whereas those of the outer shoot cortex were confined to special intravacuolar globules. The amorphous leaf flavanols were converted into globdar ones in the vicinity of fungal infections. Apparently, the central vacuole acquires special adjustment under the influence of infection stress. When paraquat was applied to the shoots, amorphous material was attached towards the cell walls. Additionally, the globular flavanols disappeared which could be reversed by addition of (+)-catechin. Thus, (+)-catechin diminished the oxidative damage caused by the oxygen radical producing herbicide. (+)-Catechin and epicatechin are the dominant flavanols of the leaves, whereas the dimeric proanthocyanidins B3 and B1 (PAs) predominate in the callus

Ermittlung der Kalium- und Calciumverteilung in Traubenachsen von Vitis vinifera mit Hilfe der Röntgenstrahlenmikroanalyse am Rasterelektronenmikroskop

Bei einem Limberger-Klon wurden Untersuchungen durchgeführt, welche Beziehungen zwischen der Kalium/Calcium-Relation und der Stiellähmeerkrankung aufzeigen. Hierfür wurde ein Verfahren mit dem Rasterelektronenmikroskop und einem Röntgenspektrometer angewandt. Es gestattet die Analyse kleinster Gewebekomplexe im Anfangsstadium der Krankheit. Untersucht wurden völlig gesunde und kranke Pflanzen - bei letzteren sowohl gesund erscheinende Stellen an Traubenstielen als auch schwach erkrankte Gewebe. Die Messungen erfolgten an der Stieloberfläche und an Querschnitten.Alle Untersuchungen zeigen, daß mit Beginn der Stiellähmekrankheit der Kalium/Calcium-Quotient größer wird. Davon sind die Oberfläche, das Rindenparenchym und auch das Xylem betroffen. Die größte Disharmonie zwischen Kalium und Calcium besteht im großzelligen Rindenparenchym.Determination of the K/Ca ratio in rachises of the vine clusters (Vitis vinifera L.) by an X-ray microanalyser with a scanning electron microscopeThe present study was conducted on rachises of Vitis vinifera L. during the early phase of stalk necrosis disease ('Stiellähme'). Amounts of K and Ca were recorded by an energy dispersion X-ray analyser with a scanning electron microscope.Samples were taken from healthy and diseased plants, the affected plants being divided into seemingly healthy and slightly necrotic tissues.In the case of the healthy-looking tissue from diseased plants, the ratio of K/Ca is high when compared with healthy plants. This tendency is accentuated in tissues with visible symptoms in the early phase of stalk necrosis disease.The imbalance between K and Ca was considerable, especially in the large parenchyma cells of the cortex and was less accentuated in the xylem and on the surface of the rachis

Two-Loop Sudakov Form Factor in a Theory with Mass Gap

The two-loop Sudakov form factor is computed in a U(1) model with a massive gauge boson and a $U(1)\times U(1)$ model with mass gap. We analyze the result in the context of hard and infrared evolution equations and establish a matching procedure which relates the theories with and without mass gap setting the stage for the complete calculation of the dominant two-loop corrections to electroweak processes at high energy.Comment: Latex, 5 pages, 2 figures. Bernd Feucht is Bernd Jantzen in later publications. (The contents of the paper is unchanged.

Is the Earth Crying Wolf? Exploring Knowledge Source and Certainty in High School Students\u27 Analysis of Global Warming News

The marked contrast between the scientific consensus on global warming and public beliefs indicates a need to research how high schoolers, as future citizens, engage with and make meaning from news articles on such topics. In the case of socioscientific issues (SSIs) such as global warming, students’ acquisition of knowledge from the news is mediated by their epistemic understandings of the nature of science (NOS) and use of informal reasoning in evaluating claims, evidence, and sources. This exploratory qualitative study examined twelve U.S. high school students’ understandings, opinions, and epistemic beliefs concerning global warming knowledge. Researchers examined microgenetic changes as students discussed global warming during semi-structured interviews and a close reading of global warming news texts. Although results showed that most students could articulate a working concept of global warming, in follow-up questions, a subset offered personal opinions that differed from or contradicted their previously stated understandings. Meanwhile, students who offered opinions consistent with the scientific consensus often argued that the dangers of global warming were exaggerated by politicians and scientists who wished to profit from the issue. This study suggests a need for more explicit focus on NOS and scientific news literacy in curricula, as well as further research into the interplay between epistemic beliefs and the informal reasoning students use to negotiate diverse sources of SSI knowledge—from the classroom to the news media and public life

Impact of humoral alloreactivity early after transplantation on the long-term survival of renal allografts

Impact of humoral alloreactivity early after transplantation on the long-term survival of renal allografts.BackgroundThe contribution of humoral alloreactivity to the rejection of renal allografts is not well defined because humoral antigraft reactions are not easily detectable in transplant biopsies, and serial measurements of circulating allo-antibodies in the post-transplantation period are not routinely performed. We have developed diagnostic techniques that improve the assessment of humoral alloreactivity in vivo and in vitro.MethodsHumoral alloreactivity in transplant biopsies derived from 218 single kidney grafts was detected by assessing the deposition of complement fragment C4d in interstitial capillaries. Circulating alloantibodies were determined in corresponding serum samples by flow cytometry using lymphoblastoid cell lines of donor DR-type as target cells and by a conventional microcytotoxicity test. The impact of capillary C4d and other selected variables on renal graft survival was calculated by univariate and multivariate analysis.ResultsCapillary C4d, present in 46% of biopsies from first grafts and 72% of regrafts, is related to circulating alloantibodies. Grafts with capillary C4d have a markedly shorter survival than grafts without capillary C4d (50% graft survival, 4 vs. 8 years, P = 0.0001). Among several risk factors, capillary C4d is the strongest predictor of subsequent graft loss in a multivariate analysis (relative risk, 2.1, 95% CI, 1.4 to 3.1). Humoral alloreactivity detectable within six months after transplantation has a much stronger impact on graft survival than alloreactivity detected beyond this period.ConclusionsHumoral alloreactivity, manifested by the capillary deposition of complement C4d in about 50% of biopsied renal grafts, exerts a strong impact on graft survival when it operates within six months after transplantation

Differential functional benefits of ultra highfield MR systems within the language network

Several investigations have shown limitations of fMRI reliability with the current standard field strengths. Improvement is expected from ultra highfield systems but studies on possible benefits for cognitive networks are lacking. Here we provide an initial investigation on a prominent and clinically highly-relevant cognitive function: language processing in individual brains. 26 patients evaluated for presurgical language localization were investigated with a standardized overt language fMRI paradigm on both 3T and 7T MR scanners. During data acquisition and analysis we made particular efforts to minimize effects not related to static magnetic field strength differences. Six measures relevant for functional activation showed a large dissociation between essential language network nodes: although in Wernicke's area 5/6 measures indicated a benefit of ultra highfield, in Broca's area no comparison was significant. The most important reason for this discrepancy was identified as being an increase in susceptibility-related artifacts in inferior frontal brain areas at ultra high field. We conclude that functional UHF benefits are evident, however these depend crucially on the brain region investigated and the ability to control local artifacts

The Two Loop Crossed Ladder Vertex Diagram with Two Massive Exchanges

We compute the (three) master integrals for the crossed ladder diagram with two exchanged quanta of equal mass. The differential equations obeyed by the master integrals are used to generate power series expansions centered around all the singular (plus some regular) points, which are then matched numerically with high accuracy. The expansions allow a fast and precise numerical calculation of the three master integrals (better than 15 digits with less than 30 terms in the whole real axis). A conspicuous relation with the equal-mass sunrise in two dimensions is found. Comparison with a previous large momentum expansion is made finding complete agreement.Comment: 42 pages, 1 figur

Return-to-activity after anatomical reconstruction of acute high-grade acromioclavicular separation

BACKGROUND: To evaluate return-to-activity (RtA) after anatomical reconstruction of acute high-grade acromioclavicular joint (ACJ) separation. METHODS: A total of 42 patients with anatomical reconstruction of acute high-grade ACJ-separation (Rockwood Type V) were surveyed to determine RtA at a mean 31 months follow-up (f-u). Sports disciplines, intensity, level of competition, participation in overhead and/or contact sports, as well as activity scales (DASH-Sport-Module, Tegner Activity Scale) were evaluated. Functional outcome evaluation included Constant score and QuickDASH. RESULTS: All patients (42/42) participated in sporting activities at f-u. Neither participation in overhead/contact sports, nor level of activity declined significantly (n.s.). 62 % (n = 26) of patients reported subjective sports specific ACJ integrity to be at least the same as prior to the trauma. Sporting intensity (hours/week: 7.3 h to 5.4 h, p = .004) and level of competition (p = .02) were reduced. If activity changed, in 50 % other reasons but clinical symptoms/impairment were named for modified behavior. QuickDASH (mean 6, range 0–54, SD 11) and DASH-Sport-Module (mean 6, range 0–56, SD 13) revealed only minor disabilities at f-u. Over time Constant score improved significant to an excellent score (mean 94, range 86–100, SD 4; p < .001). Functional outcome was not correlated with RtA (n.s.). CONCLUSION: All patients participated in sporting activities after anatomical reconstruction of high-grade (Rockwood Type V) ACJ-separation. With a high functional outcome there was no significant change in activity level (Tegner) and participation in overhead and/or contact sports observed. There was no correlation between functional outcome and RtA. Limiting, there were alterations in time spent for sporting activities and level of competition observed. But in 50 % those were not related to ACJ symptoms/impairment. Unrelated to successful re-established integrity and function of the ACJ it should be considered that patients decided not return-to-activity but are very content with the procedure