SummaryAccumulating data indicate that strigolactones (SLs) are implicated in the response to environmental stress, implying a potential effect of SLs on stomatal response and thus stress acclimatization. In this study, we investigated the molecular mechanism underlying the effect of SLs on stomatal response and their interrelation with abscisic acid (ABA) signaling.The impact of SLs on the stomatal response was investigated by conducting SL-feeding experiments and by analyzing SL-related mutants. The involvement of endogenous ABA and ABA-signaling components in SL-mediated stomatal closure was physiologically evaluated using genetic mutants. Pharmacological and genetic approaches were employed to examine hydrogen peroxide (H 2 O 2 ) and nitric oxide (NO) production.SL-related mutants exhibited larger stomatal apertures, while exogenous SLs were able to induce stomatal closure and rescue the more widely opening stomata of SL-deficient mutants. The SL-biosynthetic genes were induced by abiotic stress in shoot tissues. Disruption of ABA-biosynthetic genes, as well as genes that function in guard cell ABA signaling, resulted in no impairment in SL-mediated stomatal response. However, disruption of MORE AXILLARY GROWTH2 (MAX2), DWARF14 (D14), and the anion channel gene SLOW ANION CHANNEL-ASSOCIATED 1 (SLAC1) impaired SL-triggered stomatal closure. SLs stimulated a marked increase in H 2 O 2 and NO contents, which is required for stomatal closure.Our results suggest that SLs play a prominent role, together with H 2 O 2 /NO production and SLAC1 activation, in inducing stomatal closure in an ABA-independent mechanism.

Sulfonated poly(diphenylamine) (SPDPA) was used as a novel hole-collecting layer (HCL) in polymer photovoltaic (PV) cells. PV cells of poly(3-hexylthiophene) (P3HT):[6,6]-phenyl C 61 butyric acid methyl ester used as the active layer with SPDPA as HCL showed the higher power conversion efficiency (4.2%) and fill factor (0.68) than those with commercial poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (Baytron AI 4083) (3.6% and 0.65). The morphology change of the active layer was observed using atomic force microscopy and grazing-incidence X-ray diffraction. The hole-only device was fabricated to measure hole-injection current and hole mobility. The results show increased crystallinity of P3HT with SPDPA as HCL. The enhanced device performance is attributed to the improved hole mobility and the increased crystallinity of P3HT due to the properties of SPDPA.

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The main purpose of this quantitative research is to examine students' expectations and perceptions on the service quality of e-learning in a selected faculty of a public university in Malaysia. Data for the research are collected through a survey on sixth semester undergraduate students in one of the faculties in a public university. Questionnaire is adopted based on Parasuraman's (1994) SERVQUAL model which includes five dimensions: reliability, responsiveness, empathy, tangibility and assurance. Descriptive analysis is conducted to indicate the level of students' expectations and perceptions on service quality of e-learning as well as the gap between their expectations and perceptions. Paired t-test analysis is performed to test the significant difference between students' expectations and perceptions. The findings indicate that the level of students' expectations is high with tangibility regarded as the highest amongst the five domains examined. However, the level of students' perceptions is medium. Among the five dimensions, the level of perception towards assurance is the highest, while the level of perception towards empathy is the lowest. There exists a gap between students' expectations and students' perceptions. Paired ttest shows that there is a significant difference between students' expectations and perceptions indicating students are not highly satisfied with the service quality of e-earning provided by the selected university. Further initiatives should be taken by the university to improve the service quality of the e-learning facilities focusing on areas identified in the findings.