CO_2, H_2O exchange and stomatal regulation of regenerated Camptotheca acuminata plantlets during ex vitro acclimatization

For finding the changes in CO2, H20 exchange and their stomatal regulation during ex vitro acclimatization of regenerated Camptotheca acuminata plantlets, the net photosynthesis rate （Pn）, respiration rate （Ro）, light compensation point （Lc） and light saturation point （Ls）, transpiration rate （Tr）, stomatal conductance （gs） and water use efficiency（WUE） were measured during 37 days of ex vitro acclimatization. The results showed that Pn sharply increased until 29 days, then slightly decreased. A substantial decrease in Lc and a substantial increase of Ls in the former two weeks were observed, indicating the light regime enlargement for effective leaf photosynthesis. Tr and gs abruptly decreased during the first week then linearly increased until 29days ex vitro acclimatization, reflecting the strong regulation effect of stomata on water changes of ex vitro acclimating plantlets. Stomatal regulation effect on CO2 exchange was different from that on water exchange, i.e. P, was almost independent of gs during the first week, while P. was significantly correlated with gs thereafter （i.e. dual patterns）. Different from dual patterns of gs-Pn relation, the Tr monotonously linearly increased with gs. Furthermore, WUE was almost independent on gs during the first week, while a marked decreasing tendency with gs was found thereafter. At the beginning of the acclimatization, WUE was mainly determined by photosynthetic capacity, while transpiration becomes a main determinant factor for WUE from 7 to 37 days＇ acclimatization.

Comparison Between Diltiazem and Cedilanid-D on Ventricular Rate Control of Atrial Fibrillation and Their Effect on Atrioventricular Conduction System.

Objectives This randomized study was designed to compare the safety and efficacy of intravenous diltiazem versus intravenous cedilanid-D （deslanoside） for ventricular rate control in patients with atrial fibrillation （AF）. Analysis of the effect on conduction system of these drugs was also performed. Methods Forty three patients with AF were randomly assigned to receive intravenous therapy with 0.25mg/kg diltiazem （n = 21） or 0.4rag cedilanid-D （n = 22）. If not effective at 120 minutes （〈 20% decrease in pretreatment ventricular rate or can not convert to sinus rhythm= another dose of diltiazem or 0.2mg cedilanid-D was administered. Blood pressure and electrocardiographic recordings were performed before and after 5, 10, 20, 30, 60 minutes of drug administration. Further recordings were performed at 120 minutes in noneffective patients, and at 180 minutes in patients who received second time drug administration. To evaluate the effect on conduction system of these two drugs by measuring PA, AH and HV intervals using His bundle electrogram test another nineteen sinus rhythm patients were randomized to dihiazem （n=9） and cedilanid （n= 10） group. His bundle electrogram recordings were performed before and after 5, 10, 20 and 30 minutes of drug administration. Statistical significance was assessed with the use of t test, Fisher＇s exact test, ANOVA and LSD methodology. Results At baseline and after 5, 10, 20, 30, 60 minutes of drug administration the heart rates （mean±SD） were（133±15）, （92±20）, （87±22）, （85 ±20）, （85±21）, （85 ±23）beats/minute in diltiazem group respectively and（ 140±21 ）, （ 122±24）, （118±25）, （110±26）, （112±25）, （110±28） beats/ minute in cedilanid-D group respectively. Heart rate reduction was higher in diltiazem group than cedilanid group during 5 （41±20 vs 17±14,P 〈 0.01）; 10 （46±21 vs 22±20, P〈0.01）; 20 （48±21 vs 29±22, P〈0.01 ） ; 30（48±22 vs 27±22,P〈0.01 ）and 60 minutes （48±23 vs 29±24, P〈 0.05）. Both drugs had no effect on both systolic and diastolic blood pressure （P 〉0.05） and no major side effects were noticed. Diltiazem maintained effective ventrieular rate in 20 patients, whereas eedilanid-D maintained in 15 patients within 180 minutes （95.2%vs 68.2%,P〈 0.05）. There were no statistical significance in baseline heart rate, age and weight between the two groups. Both diltiazem and cedilanid-D can increase AH interval, but have no effect on HV and PA intervals in sinus rhythm patients. Conclusions Both dihiazem and eedilanid-D decrease ventrieular heart rate, but heart rate reduction is significantly higher in diltiazem group, thus should be considered as a drug of choice for emergency control of ventrieular rate. Under clinical monitoring this dose of diltiazem seems to be safe and applicable in AF patients with congestive heart failure. Both drugs have no effect on PA and HV intervals but increase the AH interval thereby can reduce ventricular rate.

Capacitance Performances of Supramolecular Hydrogels Based on Conducting Polymers

The capacitance performances of poly（3,4-ethylenedioxythiophene）-poly（styrenesulfonate）（PEDOT-PSS） supramolecular hydrogels have been investigated systematically. The materials show a specific capacitance of 67 F/g and display excellent rate capability at the scan rate as high as 5000 m V/s in the cyclic voltammogram measurements, accompanied by good cycle stability. On the basis of the measurements of the microscale morphologies, specific areas and electrical conductivities, the mechanisms for the improvement of the electrochemical properties are discussed and ascribed to the novel porous microstructures of the hydrogels and the synergetic effect of the rigid PEDOT and soft PSS components. Furthermore, polyaniline（PAn） is compounded with the PEDOT-PSS hydrogels through an interfacial polymerization process, endowing the hydrogel materials with a higher specific capacitance of 160 F/g at the scan rate of 5000 m V/s. The significance of this work lies in the demonstration of a novel method to solve the problems of conducting polymers in electrochemical applications.