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    Chemical reactivity of ultracold polar molecules: investigation of H + HCl and H + DCl collisions

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    Quantum scattering calculations are reported for the H+HCl(v,j=0) and H+DCl(v,j=0) collisions for vibrational levels v=0-2 of the diatoms. Calculations were performed for incident kinetic energies in the range 10-7 to 10-1 eV, for total angular momentum J=0 and s-wave scattering in the entrance channel of the collisions. Cross sections and rate coefficients are characterized by resonance structures due to quasibound states associated with the formation of the H...HCl and H...DCl van der Waals complexes in the incident channel. For the H+HCl(v,j=0) collision for v=1,2, reactive scattering leading to H_2 formation is found to dominate over non-reactive vibrational quenching in the ultracold regime. Vibrational excitation of HCl from v=0 to v=2 increases the zero-temperature limiting rate coefficient by about 8 orders of magnitude.Comment: 9 pages, 6 figures, submitted to Euro. Phys. J. topical issue on "Ultracold Polar Molecules: Formation and Collisions

    Circular 104

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    Fitness benefits of prolonged post-reproductive lifespan in women

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    Most animals reproduce until they die, but in humans, females can survive long after ceasing reproduction. In theory, a prolonged post-reproductive lifespan will evolve when females can gain greater fitness by increasing the success of their offspring than by continuing to breed themselves. Although reproductive success is known to decline in old age, it is unknown whether women gain fitness by prolonging lifespan post-reproduction. Using complete multi-generational demographic records, we show that women with a prolonged post-reproductive lifespan have more grandchildren, and hence greater fitness, in pre-modern populations of both Finns and Canadians. This fitness benefit arises because post-reproductive mothers enhance the lifetime reproductive success of their offspring by allowing them to breed earlier, more frequently and more successfully. Finally, the fitness benefits of prolonged lifespan diminish as the reproductive output of offspring declines. This suggests that in female humans, selection for deferred ageing should wane when one's own offspring become post-reproductive and, correspondingly, we show that rates of female mortality accelerate as their offspring terminate reproduction

    Soil and My Backyard

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    The purpose of this resource is to explore soil and soil properties. Students discover the variability of soils, derive relationships among soils and the soil forming factors, and link the GLOBE Soil Investigation to the students. local environment. Students use soil samples from their homes to identify properties that characterize their soils. They compare and contrast their soils to those of their classmates. As a class, students describe relationships between the properties of their soils and how and where they were sampled. Older students construct a soil classification schema. Educational levels: Primary elementary, Intermediate elementary, Middle school, High school

    Sound propagation over soft ground without and with crops and potential for surface transport noise attenuation

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    Growing demand on transportation, road, and railway networks has resulted in increased levels of annoyance from road traffic. Optimized use of green surfaces in combination with vegetation may be desirable as a method for reducing the noise impact of road traffic in urban and rural environments. Sound propagation over soft ground and through crops has been studied through outdoor measurements at short and medium ranges and through predictions. At lower frequencies, ground effect is dominant, and there is little or no attenuation due to crops. At higher frequencies above 3–4 kHz, the attenuation in crops is dominant. It was also found that the ground effects and the influence of crops can be treated independently and can be added to obtain the total effect. Sound attenuation by crops is the result of multiple scattering between the stems and leaves, loss of coherence, and viscous and thermal losses due to foliage. The major contribution is associated with viscous and thermal losses. A model for sound attenuation by vegetation is proposed. Insertion losses for a typical road traffic noise source have been calculated that result either by replacing hard ground with different types of acoustically soft ground or by growing crops along the road sides

    CORRELATION BETWEEN NEURAL RESPONSE TELEMETRY (NRT) MESUREMENT LEVEL AND BEHAVIORL (T-LEVEL AND C-LEVEL) IN PRELINGUAL COCHLEAR IMPLANT PATIENTS

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     Objectives: To study the correlation between Neural Response Telemetry (NRT) measurement level and behavioral (Threshold level and Comfort level) in pre lingual cochlear implant patients age between 2 -10 years old at one and three months post implant. Methods: A cross sectional study conducted at University Kebangsaan Malaysia Medical Center from September 2010 to January 2012. Total numbers of hundred patients were involved in this study.All recipients implanted with Nucleus 24 cochlear implant and had full insertion and normal activation of the electrode array. Comparison between intra-operative NRT measurement level and behavioral (T-level and C-level) in cochlear implant patients at one month and three months post implantation were obtained respectively. Results: This study showed the intra-operative NRT levels were seen to fall between the T and C levels in one and three months respectively. There was also a positive correlation between NRT value measurements and both T and C value measurements in both one and three months (p value 0.01). There is a fair strength of the linear relationship between NRT and behavioral level in both one and three month post implant as shown by the r value (0.4 at one month, 0.2 at three months) Conclusion: It is useful to use the NRT values to predict the behavioral T and C values in prelingual children and an additional tool for the mapping. Key words: Neural Response Telemetry (NRT); Threshold level; Comfort level; Nucleus 24 cochlear implant.

    MODEL TOURNAMENT BELAJAR ANTAR TIM (TOBAT) UNTUK PENINGKATAN PEMBELAJARAN MATAKULIAH BOLAVOLI

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    The objective of this research is revealing the efforts to improve volleyball subject instructions of Department of Health and Recreation Education, Faculty of Sport Science, Yogyakarta State University. This is an action research with one single cycle. The first cycle consisted of 4 meetings which was evaluated and reflected to plan the next cycle. The subjects of this research involved the 38 students of semester 1 of Department of Health and Recreation Education, Faculty of Sport Science, Yogyakarta State University who took the volleyball subject in the academic year of 2005. The setting of this research was in the class for 1 semester (4 meetings). The instruments of this research were observation sheets developed by the researcher. To synchronize the perception with the collaborator, the researcher conducted discussions and information sharing. On the basis of the analysis on the teaching and learning processes, it can be concluded that TGT model could improve the volleyball subject instructions in Department of Health and Recreation Education, Faculty of Sport Science, Yogyakarta State University. The improvements were in the aspects of students’ motivation, students’ participation, students’ cooperation in solving problems, more dynamic and conducive classroom situation, and active participation of the lecturer which also improved

    Guidance for students studying science

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