485 research outputs found
Who Cares? Attitudes of High School Students From Various Countries Towards Global and Domestic Environmental Issues
This study focused on attitudes of 16 year-old students from six countries towards environmental issues on domestic and global scales. Male and female students from China, Guinea, Japan, Malaysia, Ukraine and Vietnam expressed their level of concern about the following in regard to their country and the world: (a) air quality, (b) drinking water quality, (c) pollution caused by atomic power plants, (d) clearing of forests, (e) extinction of plants and animals, (f) climate change and (g) global disaster. This research focused on gender and cultural variability and invariance under diverse conditions of students’ backgrounds.
The most pronounced intercultural regularity found was the prioritization of certain issues. In all countries, both genders showed similar priorities when assessing global and domestic environmental issues. The differences were mainly in the level of anxiety expressed towards environmental problems. While in some countries the level of concern expressed by girls was higher than that of boys, there was no such pattern across all cultures. Only in Japan were the ratings given by boys higher when comparing to those of girls.
Another intercultural regularity was that the level of concern about the world’s environmental problems listed above is higher for both genders than about own country with exceptions of specific pressing national problems
Cellular excitability and the regulation of functional neuronal identity: from gene expression to neuromodulation
The intrinsic properties of a neuron determine the translation of synaptic input to axonal output. It is this input– output relationship that is the heart of all nervous system activity. As such, the overall regulation of the intrinsic excitability of a neuron directly determines the output of that neuron at a given point in time, giving the cell a unique “functional identity.” To maintain this distinct functional output, neurons must adapt to changing patterns of synaptic excitation. These adaptations are essential to prevent neurons from either falling silent as synaptic excitation falls or becoming saturated as excitation increases. In the absence of stabilizing mechanisms, activity-dependent plasticity could drive neural activity to saturation or quiescence. Furthermore, as cells adapt to changing patterns of synaptic input, presumably the overall balance of intrinsic conductances of the cell must be maintained so that reliable output is achieved (Daoudal and Debanne, 2003; Turrigiano and Nelson, 2004; Frick and Johnston, 2005). Although these regulatory phenomena have been well documented, the molecular and physiological mechanisms involved are poorly understood
Parents’ perceptions on previous and current science education system in Japan
Parents’ views, beliefs, and experiences greatly affect children’s attitudes toward education. The research aimed to identify the parents’ perception in the past, present, and their desired priorities in science education as well as investigated the adolescents’ perceptions based on gender and academic performance on science. As a survey study, this research relied on a questionnaire as the primary method of data collection which the data gained then was analysed by using statistical descriptive (percentage). The results showed that the priorities in education have shifted toward physics and chemistry in recent decades. Moreover, biology and earth science were found to be perceived as ‘easy’ and ‘secondary’ areas in comparison to the ‘superior’ ones (physics and chemistry). This has been strengthened by the critical situation for earth science, as the education system of Japan often does not al low the students to select it. Thus, the parents wished for a more balanced system. There was a difference in adolescents’ perceptions of science areas based on gender and academic performance. Physics and chemistry were associated with boys and top performers, while biology and earth science were supposed to ‘fit’ girls and low performers
Mining recent brain proteomic databases for ion channel phosphosite nuggets
Voltage-gated ion channels underlie electrical activity of neurons and are dynamically regulated by diverse cell signaling pathways that alter their phosphorylation state. Recent global mass spectrometric–based analyses of the mouse brain phosphoproteome have yielded a treasure trove of new data as to the extent and nature of phosphorylation of numerous ion channel principal or α subunits in mammalian brain. Here we compile and review data on 347 phosphorylation sites (261 unique) on 42 different voltage-gated ion channel α subunits that were identified in these recent studies. Researchers in the ion channel field can now begin to explore the role of these novel in vivo phosphorylation sites in the dynamic regulation of the localization, activity, and expression of brain ion channels through multisite phosphorylation of their principal subunits
The Dixmier property and tracial states for C*-algebras
A.T. was partially supported by an NSERC Postdoctoral Fellowship and through the EPSRC grant EP/N00874X/1. Acknowledgements We are grateful to Luis Santiago for helpful discussions at an early stage of this investigation. We would also like to thank the referee for providing helpful comments, which have led to a number of improvements.Peer reviewedPublisher PD
Clustering of the K<sup>+</sup> channel GORK of Arabidopsis parallels its gating by extracellular K<sup>+</sup>
GORK is the only outward-rectifying Kv-like K<sup>+</sup> channel expressed in guard cells. Its activity is tightly regulated to facilitate K<sup>+</sup> efflux for stomatal closure and is elevated in ABA in parallel with suppression of the activity of the inward-rectifying K<sup>+</sup> channel KAT1. Whereas the population of KAT1 is subject to regulated traffic to and from the plasma membrane, nothing is known about GORK, its distribution and traffic in vivo. We have used transformations with fluorescently-tagged GORK to explore its characteristics in tobacco epidermis and Arabidopsis guard cells. These studies showed that GORK assembles in puncta that reversibly dissociated as a function of the external K<sup>+</sup> concentration. Puncta dissociation parallelled the gating dependence of GORK, the speed of response consistent with the rapidity of channel gating response to changes in the external ionic conditions. Dissociation was also suppressed by the K<sup>+</sup> channel blocker Ba<sup>2+</sup>. By contrast, confocal and protein biochemical analysis failed to uncover substantial exo- and endocytotic traffic of the channel. Gating of GORK is displaced to more positive voltages with external K<sup>+</sup>, a characteristic that ensures the channel facilitates only K<sup>+</sup> efflux regardless of the external cation concentration. GORK conductance is also enhanced by external K<sup>+</sup> above 1 mM. We suggest that GORK clustering in puncta is related to its gating and conductance, and reflects associated conformational changes and (de)stabilisation of the channel protein, possibly as a platform for transmission and coordination of channel gating in response to external K<sup>+</sup>
SUMO modification of cell surface Kv2.1 potassium channels regulates the activity of rat hippocampal neurons
Voltage-gated Kv2.1 potassium channels are important in the brain for determining activity-dependent excitability. Small ubiquitin-like modifier proteins (SUMOs) regulate function through reversible, enzyme-mediated conjugation to target lysine(s). Here, sumoylation of Kv2.1 in hippocampal neurons is shown to regulate firing by shifting the half-maximal activation voltage (V1/2) of channels up to 35 mV. Native SUMO and Kv2.1 are shown to interact within and outside channel clusters at the neuronal surface. Studies of single, heterologously expressed Kv2.1 channels show that only K470 is sumoylated. The channels have four subunits, but no more than two non-adjacent subunits carry SUMO concurrently. SUMO on one site shifts V1/2 by 15 mV, whereas sumoylation of two sites produces a full response. Thus, the SUMO pathway regulates neuronal excitability via Kv2.1 in a direct and graded manner
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