Cytoplasmic polyadenylation controls cdc25B mRNA translation in rat oocytes resuming meiosis

Resumption of meiosis in oocytes represents the entry into M-phase of the cell cycle and is regulated by the maturation-promoting factor (MPF). Activation of MPF is catalyzed by the dual specificity phosphatase, cdc25. In mammals, cdc25 is represented by a multigene family consisting of three isoforms: A, B and C. A recent report that female mice lacking cdc25B exhibit impaired fertility suggests a role for this isoform in regulating the G2- to M-transition in mammalian oocytes. Supporting the above-mentioned observation, we demonstrate herein that microinjection of neutralizing antibodies against cdc25B interfered with the ability of rat oocytes to undergo germinal vesicle breakdown (GVB). We also show accumulation of cdc25B in GVB oocytes and a transient reduction in its amount at metaphase I of meiosis. The accumulation of cdc25B was associated with its mRNA cytoplasmatic polyadenylation and was prevented by the protein synthesis inhibitor cyclohexamide as well as by the polyadenylation inhibitor cordycepin. Immunofluorescence staining revealed translocation of cdc25B to the metaphase II spindle apparatus. Taken together, our findings provide evidence that cdc25B is involved in resumption of meiosis in rat oocytes. We further demonstrate for the first time, a periodic accumulation of cdc25B throughout meiosis that is translationally regulated and involves cdc25B mRNA polyadenylation.     

Consultant's involvement and its consequences in consultant–client verbal interaction.

48 undergraduate psychology students, forming 24 consultant–client dyads, role-played in 2 consultation sessions, each of which was under a different type of consultant's involvement. Tape recordings of these 48 simulated sessions were analyzed. As hypothesized, instructions eliciting the consultant's involvement in the "problem," as compared with those instructions creating involvement with the "client," resulted in a higher level of verbal activity on the part of the consultant, more frequent mutual interruptions, and more response incongruence in the conversation. Individual differences tended to be preserved consistently across the experimental conditions. The present study and other studies concerning noncontent measures of verbal behavior in interviews are discussed, concluding that investigation of interviewers' attitudes towards their clients is of value for defining different approaches to counseling according to what is done and for training programs based on behavior. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Biological activity of synthetic hydrocarbon mixtures of cuticular components of the female housefly (Musca domestica L.)

Mixtures of (Z)-9-alkenes (C₂₁-C₃₃),n-alkanes (C₂₁-C₃₃), and mono- and dimethylalkanes (C₂₇, C₂₉), as components of the cuticular lipids washed from the female housefly (Musca domestica L.), were synthesized and assayed for their biological activity on male houseflies. The (Z)-9-alkenes and their hydrogenatedn-alkanes were synthesized from jojoba wax components by the appropriate chain elongation. The methylalkanes were prepared by Grignard coupling reaction of the appropriate alkyl halides, catalyzed by Li₂CuCl₄. Six- to 7-day-old virgin male houseflies exhibited the highest mating strike activity toward 6- to 7-day-old virgin females. The mating strike activity of the synthetic hydrocarbons was studied by exposing 6- to 7-day old virgin males to petrol-ether-rinsed 1 to 2-day-old dead females treated with these chemicals. (Z)-9-Tricosene was the most active hydrocarbon tested when it was applied in amounts of 10 g to a washed dead female. Amounts of 5 g of (Z)-9-tricosene did not cause sexual activity in the males. Mixture of (Z)-9-alkenes showed low activity when applied at 10-g amounts. However, when mixtures were made of 5 g of (Z)-9-tricosene with 5 fig of each of certain mixtures of (Z)-9-alkenes, the striking activity became as high as that of 10 g of (Z)-9-tricosene. This might be a synergism effect. The mixtures ofn-alkanes, as well as the mono- and dimethylalkanes, showed moderate activity. When (Z)-9-tricosene was added to these materials no increase in male activity was observed.     

Investigating the possibility of using different hub height wind turbines in a wind farm

Many researchers have focused on the layout design of a wind farm using the computational methods. Most of previous researches focused on relevant large cell size and using same hub height wind turbines. In this paper, the authors investigate the possibility of using different hub height wind turbines in a wind farm. A limited area (2?km?×?2?km) with constant wind speed and direction is considered as the potential wind farm area, and a nested genetic algorithm is used as optimisation algorithm. Two different hub height wind turbines are introduced with two different cell sizes. Power output, cost, payback period, and total profit are selected as evaluation criteria when comparing the layouts with same hub height wind turbines with the layouts with different hub height wind turbines. The results demonstrate that it is feasible and possible to use different hub height wind turbines in a wind farm.     

Gemini Cationic Surfactants: Synthesis and Influence of Chemical Structure on the Surface Activity

Three cationic gemini surfactants were synthesized and characterized using different methods. Their surface activities were measured using surface and interfacial tension measurements. The effect of the spacer chain length on the surface activity, emulsification power and interfacial tension was studied. The thermodynamic parameters showed the tendency towards micellization and adsorption. The results showed that longer spacers increased the micellization tendencies of the surfactants, while shorter spacers increased the adsorption tendency at the air–water interface.     

Synthesis,Characterization, Surface,and Thermodynamic Studies of Alkyl Tetrachloroferrates: Performance Evaluation of Their Nanostructures as Biocides

Decyl and dodecylamino tetrachloroferrates were synthesized and characterized using Fourier-transform infrared spectroscopy (FTIR), elemental analysis, X-ray diffraction (XRD), nuclear magnetic resonance (¹H-NMR), and atomic absorption spectroscopy (AAS). The surface properties of the cationic surfactants including critical micelle concentration, effectiveness, minimum surface area, and maximum surface excess were determined using surface tension measurements. The effectiveness of surface tension reduction (π_cmc) was found to increase as the hydrophobic chain length increases with values of 30 and 34 mN m⁻¹ for C₁₀ and C₁₂, respectively. Moreover, the effect of temperature on micellization was determined over the range of 35–55 °C. Thermodynamic parameters (ΔG°, ΔS°, and ΔH°) were calculated and the results indicate a spontaneous process for both micellization and adsorption. The nanoparticles (NC₁₀ and NC₁₂) of the prepared surfactants were obtained using the ball mill technique. The particle size and morphology of the nanoparticles were determined using transmission electron microscope measurements. The antibacterial study of the nanoparticle surfactants revealed their strong efficiency against fungi and different pathogenic bacteria compared with the original surfactants.     

Assessment of post-Kyoto climate change mitigation regimes impact on sustainable development

This article analyzes post-Kyoto climate change mitigation regimes and their impact on sustainable development. Wide range of post-Kyoto climate change mitigation architectures have different impact on different groups of countries, therefore sustainability assessment is performed for four main group of countries: EU and other Annex-I countries, USA, Advanced Developing Countries and Least Developed Countries. The post-Kyoto climate change mitigation regimes are evaluated based on their economical, environmental, social and political impact for different groups of countries. For the assessment the scoring is applied. The architectures are further ranked according to the best results or highest score obtained during assessment according to all criteria and for all groups of countries.     

Modulation of sensorimotor rhythms for brain-computer interface using motor imagery with online feedback

This research studies the impact of the imagination of movements and associated feedbacks on the modulation of sensorimotor electroencephalographic (EEG) rhythms, for the online controls of a brain-computer interface (BCI). Nine subjects with no physical or mental impairments were selected. The number of sessions was five: one calibration and four feedback sessions. A computer screen’s cursor movement was controlled in one dimension using EEG-based four-class BCI involving motor imagery tasks of moving the right hand, the left hand, both hands, or both feet. Our findings reveal that the visual feedback applied during motor imagery movement modulates sensorimotor EEG rhythms clearly in the mu and beta bands. The analyses of event-related desynchronization/synchronization (ERD/ERS) suggest significant differences between brain activities in the calibration and feedback sessions; large ERDs during the online feedback sessions compared to that in the calibration session have been observed. The increasing ERDs in the online feedback session were noticed over the mu1 (8–10 Hz) and upper beta (18–24 Hz) rhythms, resulting in the cursor control success rate at 73.3%.     

Computer-supported reflective learning: how apps can foster reflection at work

ABSTRACT

This paper discusses the potential of ICT to support reflective learning for professionals. We aggregated data collected in 20 field studies with 12 different applications, involving a total of 321 participants. The applications addressed individual reflection as well as collaborative reflection. Such a systematic analysis with different applications used across industry sectors and companies is unique in the current literature on computer-supported reflective learning in the workplace. Primarily, we assessed the reaction to reflection applications and their effectiveness regarding learning, behaviour change, and organisational impact. In addition, we investigated differences with respect to work experience. Results show that users had a positive reaction to the apps and perceived their use to be beneficial for their work by using them. In collaborative reflection an inexperienced employee can benefit from the experiences and perspectives of more experienced (co-)workers. In contrast, individual reflection was more profitable for more experienced workers. Notwithstanding the overall positive results, the actual implementation of reflection applications requires careful adaptation to the specific organisational and situational context, as well as introductory and accompanying measures to assure efficient and beneficial usage of the tools.