Superhumps in a Peculiar SU UMa-Type Dwarf Nova ER Ursae Majoris

We report the photometry of a peculiar SU UMa-type dwarf nova - ER UMa for ten nights during 1998 December and 1999 March covering a complete rise to the supermaximum and a normal outburst cycle. Superhumps have been found during the rise to the superoutburst. A negative superhump appeared in Dec.22 light curve, while the superhump on the next night became positive and had large amplitude and distinct waveform from that of the previous night. In the normal outburst we captured, superhumps with larger or smaller amplitudes seem to always exist, although it is not necessarily true for every normal outburst. These results show great resemblance with V1159 Ori (Patterson et al. 1995). It is more likely that superhumps occasionally exist at essentially all phases of the eruption cycles of ER UMa stars, which should be considered in modeling.Comment: 4 pages, 5 figures, Accepted by ApJ Letter

MECHANISM OF ALUMINUM TOXICITY AVOIDANCE IN TROPICAL RICE (Oryza sativa), MAIZE (Zea mays), AND SOYBEAN (Glycine max)

Planting Al tolerant crops is an economically justifiable approach in crop production on acid soils. Experiments were conducted to study the mechanisms of Al tolerance among species and varieties of tropical rice, maize, and soybean with previously known levels of Al tolerance. These varieties were hydroponically cultured in 0, 5, 10, and 30 mg l-1 Al with complete nutrient solution at pH 4. The results show that root/shoot ratio of dry weight at 10 mg l-1 Al treatment was an important parameter to indicate differential Al tolerance in maize. Oxalic acid exudation from roots cannot always explain the Al tolerance. Total organic acid concentration in roots at 10 mg l-1 Al treatment indicated a difference of Al tolerance in soybean and lowland rice. Aluminum translocation from roots to shoots was lower in  tolerant varieties than in sensitive varieties of soybean. Increased Al concentration in shoots with increased Al level in the solution was larger in soybean and maize than in lowland or upland rice. Among varieties of  soybean, the Al concentration in shoots increased drastically in Wilis (Al-sensitive variety) with increase Al level, while in Kitamusume (Al-tolerant variety) it did not

In-the-Gap SU UMa-Type Dwarf Nova, Var73 Dra with a Supercycle of about 60 Days

An intensive photometric-observation campaign of the recently discovered SU UMa-type dwarf nova, Var73 Dra was conducted from 2002 August to 2003 February. We caught three superoutbursts in 2002 October, December and 2003 February. The recurrence cycle of the superoutburst (supercycle) is indicated to be $\sim$60 d, the shortest among the values known so far in SU UMa stars and close to those of ER UMa stars. The superhump periods measured during the first two superoutbursts were 0.104885(93) d, and 0.10623(16) d, respectively. A 0.10424(3)-d periodicity was detected in quiescence. The change rate of the superhump period during the second superoutburst was $1.7\times10^{-3}$, which is an order of magnitude larger than the largest value ever known. Outburst activity has changed from a phase of frequent normal outbursts and infrequent superoutbursts in 2001 to a phase of infrequent normal outbursts and frequent superoutbursts in 2002. Our observations are negative to an idea that this star is an related object to ER UMa stars in terms of the duty cycle of the superoutburst and the recurrence cycle of the normal outburst. However, to trace the superhump evolution throughout a superoutburst, and from quiescence more effectively, may give a fruitful result on this matter.Comment: 9 pages, 8 figures, submitted to A&

Expression of membrane-anchored matrix metalloproteinase inhibitor reversion inducing cysteine rich protein with kazal motifs in murine cell lines

Aim: It has been demonstrated that the endogenous matrix metalloproteinases (MMPs) inhibitor reversion inducing cysteine rich protein with Kazal motifs (RECK) is a reliable prognostic marker for detecting several types of tumors. However, the RECK expressions in most of the normal and neoplastic tissues were extremely low, and to measure its expression is quite complicated. The purpose of the present study is to establish an easy method to quantify murine RECK mRNA expression for use in future experimental studies. Subsequently, in order to verify the reliability of the established quantification technique, we examined the change in RECK expression and gelatinase secretion in tumor cells when stimulated by the extracellular matrix. Methods: Several murine tumor cells were used in the present study. The real-time polymerase chain reaction (PCR) method and measurement conditions for murine RECK mRNA were studied using these tumor cells. Gelatinase activities were also examined by gelatin zymography. Results: Murine RECK mRNA expression was accurately quantified using real-time PCR. Among the tumor cells used in the study, osteosarcoma cells showed significantly higher RECK mRNA expression than the others. The RECK expression in the osteosarcoma cells was down-regulated by contact with matrigel-coated culture flasks due to increased secretion of gelatinases. Conclusion: The real-time PCR method employed in our study is useful to quantify RECK expression.Показано, что эндогенный ингибитор матриксных протеиназ (MMП) RECK может служить надежным прогностическим маркером для некоторых типов опухолей, однако его экспрессия в большинстве нормальных и неопластических тканей крайне низкая, поэтому возникают сложности, связанные с детекцией таковой. Цель работы — разработка количественного метода определения экспрессии мРНК для использования в экспериментальных исследованиях. Для дальнейшего подтверждения надежности разработанного метода исследованы изменения экспрессии RECK и секреции желатиназ в опухолевых клетках при стимуляции внеклеточным матриксом. Методы: в работе использовали несколько линий опухолевых клеток мыши, в которых экспрессию мРНК RECK анализировали методом ПЦР в режиме реального времени, активность желатиназ — методом зимографии. Результаты: экспрессию мРНК RECK количественно оценили методом ПЦР в режиме реального времени, причем среди исследованных клеточных линий наиболее высокий уровень экспрессии RECK выявили в клетках остеосаркомы. Экспрессия RECK в клетках остеосаркомы подавлялась при контакте с культуральным пластиком, обработанным матригелем, вследствие повышения секреции желатиназ. Выводы: для количественной оценки экспрессии мРНК RECK может быть использован метод ПЦР в режиме реального времени

Anisotropic magnetic fluctuations in the ferromagnetic superconductor UCoGe studied by angle-resolved ^{59}Co NMR

We have carried out direction-dependent ^{59}Co NMR experiments on a single crystal sample of the ferromagnetic superconductor UCoGe in order to study the magnetic properties in the normal state. The Knight shift and nuclear spin-lattice relaxation rate measurements provide microscopic evidence that both static and dynamic susceptibilities are ferromagnetic with strong Ising anisotropy. We discuss that superconductivity induced by these magnetic fluctuations prefers spin-triplet pairing state.Comment: 4 pages, 4 figure

Is CSR a magic word?: An exploring study of consumer behaviour in cosmetic market in Thailand

Many authors stated that decision-making today is more complex than in the past, especially when they are being confronted by various kinds of product (eg.: Hafstrom et al., 1992; Lysonski et al., 1995; Mitchell et al., 1998). Thailand is an example of a developing country where a huge number of products from various countries imported cosmetic products. Due to the competition in Thailand, cosmetic market is always very intense; therefore it is important for firms to understand the factors that affect the consumers purchasing behaviour. At the same time, Corporate Social Responsibility (CSR) has been one of the most popular theme for academics and marketers when they analyse its impact on consumers’ behaviour (Maignan and Ferrel, 2004; Smith, 2003). Does CSR have a positive impact on Thai consumers’ purchasing intention? To investigate this theme based on quantitative approach, we analyse the impact of CSR factor as an antecedent factor for Thai consumers’ attitudes towards cosmetic products, drawing the pathways resulting in their final decision of purchasing

Gravitational level effects o optical properties of electrodeposited ZnO nanowire arrays

The coupling phenomena between the interfacial reaction rate and the microstructural/morphological variation rate must be reasonably well controlled to fabricate nano/meso- structural devices in a large scale. Otherwise, the physical property uniformity inside the device is not guaranteed to lose its superiority in the market. Free standing ZnO nanowire array was successfully synthesized on ITO/FTO substrate by template-free method in Zn(NO3)2 aqueous solutions. Two types of electrode configurations were employed in order to quantitatively examine the effect of gravitational strength on electrodeposited ZnO nanowire array: (a) a horizontal cathode surface facing downward over an anode (C/A) and (b) an anode over a cathode (A/C). The former configuration may simulate the microgravitational environment, because macroscopic natural convection is not induced. PL of ZnO nanowire array was measured. More uniform nanowires are synthesized in C/A configuration than in A/C. Seeding ZnO nanoparticles on ITO/FTO substrate can control the diameter as well as the orientation. Please click Additional Files below to see the full abstract