REACTIVITY OF CHLOROPHYLL a/b-PROTEINS AND MICELLAR TRITON X-100 COMPLEXES OF CHLOROPHYLLS a OR b WITH BOROHYDRIDE

The reaction of several plant chlorophyll-protein complexes with NaBH4 has been studied by absorption spectroscopy. In all the complexes studied, chlorophyll b is more reactive than Chi a, due to preferential reaction of its formyl substituent at C-7. The complexes also show large variations in reactivity towards NaBH4 and the order of reactivity is: LHCI > PSII complex > LHCII > PSI > P700 (investigated as a component of PSI). Differential pools of the same type of chlorophyll have been observed in several complexes. Parallel work was undertaken on the reactivity of micellar complexes of chlorophyll a and of chlorophyll b with NaBH4 to study the effect of aggregation state on this reactivity. In these complexes, both chlorophyll a and b show large variations in reactivity in the order monomer > oligomer > polymer with chlorophyll b generally being more reactive than chlorophyll a. It is concluded that aggregation decreases the reactivity of chlorophylls towards NaBH4 in vitro, and may similarly decrease reactivity in naturally-occurring chlorophyll-protein complexes

Improved measurement of the K+->pi+nu(nu)over-bar branching ratio

An additional event near the upper kinematic limit for K+-->pi(+)nu(nu) over bar has been observed by experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+-->pi(+)nu(nu) over bar)=(1.47(-0.89)(+1.30))x10(-10) based on three events observed in the pion momentum region 211<P<229 MeV/c. At the measured central value of the branching ratio, the additional event had a signal-to-background ratio of 0.9

Improved Measurement of the K+ to pi+ nu nubar Branching Ratio

An additional event near the upper kinematic limit for K+ to pi+ nu nubar has been observed by Experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+ to pi+ nu nubar)= 1.47 (+1.30, - 0.89) x 10-10 based on three events observed in the pion momentum region 211<P<229 MeV/c. At the measured central value of the branching ratio, the additional event had a signal-to-background ratio of 0.9

3T MRI evaluation of regional catecholamine-producing tumor-induced myocardial injury.

Objective: Regional differences in cardiac magnetic resonance, which can reveal catecholamine-induced myocardial injury in patients with pheochromocytoma, have not yet been assessed using 3T magnetic resonance imaging. We evaluated these differences using myocardial T1-mapping and strain analysis. Design and Methods: We retrospectively reviewed 16 patients newly diagnosed with catecholamine-producing tumors (CPT group) and 16 patients with essential hypertension (EH group), who underwent cardiac magnetic resonance imaging between May 2016 and March 2018. We acquired 3T magnetic resonance cine and native T1-mapping images and performed feature-tracking-based strain analysis in the former. Results: Global cardiac function, morphology, global strain and peak strain rate were similar, but end-diastolic wall thickness differed between groups (CPT vs EH: 10.5 ± 1.7 vs 12.6 ± 2.8 mm; P < 0.05). Basal, but not apical, circumferential strain was significantly higher in the CPT than the EH group (19.4 ± 3.2 vs 16.8 ± 3.6 %; P < 0.05). Native T1 values were significantly higher in CPT than in EH patients, in both the basal septum (1307 ± 48 vs 1241 ± 45 ms; P < 0.01) and the apical septum (1377 ± 59 vs 1265 ± 58 ms; P < 0.01) mid-walls. In the CPT, but not in the EH group, native T1 values in the apical wall were significantly higher than those in the basal wall (P < 0.01). Conclusion: 3T magnetic resonance-based T1-mapping can sensitively detect subclinical catecholamine-induced myocardial injury; the influence of catecholamines may be greater in the apical than in the basal wall

Oxyanion doping strategies to enhance the ionic conductivity in Ba2In2O5

In this paper we report the successful incorporation of phosphate and sulphate groups into the ionic conductor, Ba2In2O5, with the samples analysed through a combination of X-ray diffraction, NMR, TGA, Raman spectroscopy and conductivity measurements. The results show that such oxyanion incorporation leads to a conversion from an ordered brownmillerite-type structure to a disordered perovskite-type, and hence increases the conductivity at temperatures < 800○C. In wet atmospheres, there is evidence for a significant enhancement of the conductivity through a protonic contribution.\u

Search for the decay K+ to pi+ gamma gamma in the pi+ momentum region P>213 MeV/c

We have searched for the K+ to pi+ gamma gamma decay in the kinematic region with pi+ momentum close to the end point. No events were observed, and the 90% confidence-level upper limit on the partial branching ratio was obtained, B(K+ to pi+ gamma gamma, P>213 MeV/c) < 8.3 x 10-9 under the assumption of chiral perturbation theory including next-to-leading order ``unitarity'' corrections. The same data were used to determine an upper limit on the K+ to pi+ gamma branching ratio of 2.3 x 10-9 at the 90% confidence level.Comment: 15 pages, 3 figures; no change in the results, accepted for publication in Physics Letters