Migration, Risk and Livelihoods: A Chinese Case

China has turned from a ‘low risk’ to a ‘high risk’ society since the start of the market reforms in the late 1970s. Market, while bringing diverse livelihood opportunities to rural people, has simultaneously distributed risks, and the exposure and vulnerability to them unequally among different social groups. This paper attempts to apply the risk concept to the study of one of the most socially disadvantaged groups in China, namely rural-urban migrants, through analysing the narratives of members of a migratory family of the Hui Muslim national minority from the Qinghai-Tibet Plateau, who run a business in the northern city of Tianjin. Drawing on ethnographic fieldwork, the research adopts an actor-oriented perspective combined with qualitative longitudinal research methodology (or ‘extended case method’) to delineate a livelihood trajectory of this family, and explore the relationships between livelihood, risk, social networks, agency and public policy interventions

Les punitions à l’école primaire

Le sujet de ce travail étant la punition, différents types de sanctions seront évoqués. En effet, la punition fait partie d’une des catégories de sanctions : celles dites « négatives ». Il sera également évoqué des sanctions dites « positives » pouvant remplacer l’usage de la punition. Dans ce travail, je ne m’intéresserai pas à toutes les sanctions. Je ne m’intéresserai qu’aux sanctions données dans le cadre scolaire suite à un problème de discipline uniquement. Je laisserai donc de côté les sanctions données après un travail non‐fait ou mal fait ainsi que celles données dans le cercle familial ou autre. De plus, à l’aide de cette recherche, je m’intéresserai aux habitants et aux enseignants du canton de Neuchâtel uniquement afin d’éviter les comparaisons pédagogiques entre les différents cantons. Il aurait pu être intéressant de confronter les cantons de Genève et de Neuchâtel sur le plan pédagogique, car je suis moi‐même genevoise. Cependant, pour ce travail, j’ai choisi de comparer l’évolution pédagogique dans le temps et dans les genres et non par l’aspect géographique. [...] Mon travail consistera donc à savoir si l’abolition de la punition est possible et surtout ce que pense la société sur le sujet puisqu’une telle décision ne peut être prise, d’après moi, sans que la société soit prête à mettre cela en place et à changer ses habitudes

Hybrid GMR Sensor Detecting 950 pT/sqrt(Hz) at 1 Hz and Room Temperature.

Advances in the magnetic sensing technology have been driven by the increasing demand for the capability of measuring ultrasensitive magnetic fields. Among other emerging applications, the detection of magnetic fields in the picotesla range is crucial for biomedical applications. In this work Picosense reports a millimeter-scale, low-power hybrid magnetoresistive-piezoelectric magnetometer with subnanotesla sensitivity at low frequency. Through an innovative noise-cancelation mechanism, the 1/f noise in the MR sensors is surpassed by the mechanical modulation of the external magnetic fields in the high frequency regime. A modulation efficiency of 13% was obtained enabling a final device's sensitivity of ~950 pT/Hz1/2 at 1 Hz. This hybrid device proved to be capable of measuring biomagnetic signals generated in the heart in an unshielded environment. This result paves the way for the development of a portable, contactless, low-cost and low-power magnetocardiography device

Utility and lower limits of frequency detection in surface electrode stimulation for somatosensory brain-computer interface in humans

Objective: Stimulation of the primary somatosensory cortex (S1) has been successful in evoking artificial somatosensation in both humans and animals, but much is unknown about the optimal stimulation parameters needed to generate robust percepts of somatosensation. In this study, the authors investigated frequency as an adjustable stimulation parameter for artificial somatosensation in a closed-loop brain-computer interface (BCI) system. Methods: Three epilepsy patients with subdural mini-electrocorticography grids over the hand area of S1 were asked to compare the percepts elicited with different stimulation frequencies. Amplitude, pulse width, and duration were held constant across all trials. In each trial, subjects experienced 2 stimuli and reported which they thought was given at a higher stimulation frequency. Two paradigms were used: first, 50 versus 100 Hz to establish the utility of comparing frequencies, and then 2, 5, 10, 20, 50, or 100 Hz were pseudorandomly compared. Results: As the magnitude of the stimulation frequency was increased, subjects described percepts that were “more intense” or “faster.” Cumulatively, the participants achieved 98.0% accuracy when comparing stimulation at 50 and 100 Hz. In the second paradigm, the corresponding overall accuracy was 73.3%. If both tested frequencies were less than or equal to 10 Hz, accuracy was 41.7% and increased to 79.4% when one frequency was greater than 10 Hz (p = 0.01). When both stimulation frequencies were 20 Hz or less, accuracy was 40.7% compared with 91.7% when one frequency was greater than 20 Hz (p < 0.001). Accuracy was 85% in trials in which 50 Hz was the higher stimulation frequency. Therefore, the lower limit of detection occurred at 20 Hz, and accuracy decreased significantly when lower frequencies were tested. In trials testing 10 Hz versus 20 Hz, accuracy was 16.7% compared with 85.7% in trials testing 20 Hz versus 50 Hz (p < 0.05). Accuracy was greater than chance at frequency differences greater than or equal to 30 Hz. Conclusions: Frequencies greater than 20 Hz may be used as an adjustable parameter to elicit distinguishable percepts. These findings may be useful in informing the settings and the degrees of freedom achievable in future BCI systems

Discovery of Two Simultaneous Kilohertz Quasi-Periodic Oscillations in KS 1731-260

We have discovered two simultaneous quasi-periodic oscillations (QPOs) at 898.3+/-3.3 Hz and 1158.6+/-9.0 Hz in the 1996 August 1 observation of the low-mass X-ray binary KS 1731-260 with the Rossi X-ray Timing Explorer. The rms amplitude and FWHM of the lower frequency QPO were 5.3+/-0.7 % and 22+/-8 Hz, whereas those of the higher frequency QPO were 5.2+/-1.0 % and 37+/-21 Hz. At low inferred mass accretion rate both QPOs are visible, at slightly higher mass accretion rate the lower frequency QPO disappears and the frequency of the higher frequency QPO increases to ~1178 Hz. At the highest inferred mass accretion rate this QPO is only marginally detectable (2.1 sigma) near 1207 Hz, which is the highest frequency so far observed in an X-ray binary. The frequency difference (260.3+/-9.6 Hz) between the QPOs is equal to half the frequency of the oscillations observed in a type I burst in this source (at 523.92+/-0.05 Hz, Smith, Morgan and Bradt 1997). This suggests that the neutron star spin frequency is 261.96 Hz (3.8 ms), and that the lower frequency QPO is the beat between the higher frequency QPO, which could be a preferred orbital frequency around the neutron star, and the neutron star spin. During the 1996 August 31 observation we detected an additional QPO at 26.9+/-2.3 Hz, with a FWHM and rms amplitude of 11+/-5 Hz and 3.4+/-0.6 %.Comment: 6 pages including 3 figures, Astrophysical Journal Letters, in press (issue 482

The Production of Cauliflower Microshoots using Curd Meristematic Tissues and Hypocotyl–derived Callus.

The capacity for microshoot production from cauliflower was investigated applying two different protocols. In the first, cauliflower curd meristematic tissue was used as a source of explants. The meristematic layer was shaved off and the clusters produced were homogenised using a commercial blender. In terms of its effect on the number and viability of microshoots, the use of 30 s blending duration treatment was found to be optimal between several treatments tested in the range 15 to 120 sec. Explants were cultivated in agitated S23 (MS (Murashige and Skoog, 1962) + 3 % sucrose) liquid media supplemented with different combinations of plant growth regulators. The use of 2 mg/L kinetin and 1 mg/L IBA gave the optimal results in terms of the number and viability of microshoots. The second protocol was designed to investigate the regeneration potential of hypocotyl explants of cauliflower via callus culture. The callus tissue was initiated from hypocotyl explants in callus induction medium (CIM), which consisted of S23 supplemented with 2,4-D at 1 mg/L and kinetin at 1.5 mg/L. The highest number of shoots was obtained after 28 days from sub-cultured hypocotyl derived callus on S23 basal media containing 0.5 mg/L of kinetin. This study demonstrated the ability of producing microshoots using various parts of cauliflower through both callus and without callus formation which can be useful in the later applications of cauliflower tissue culture such as the production of artificial seeds

Évaluer le potentiel en économie d'énergie du centre scolaire et de l'église de la commune de Chippis

L’objectif principal de ce travail est d’effectuer un audit énergétique sur l’ancien centre scolaire et l’église de Chippis. Il convient cependant de noter que ce travail sera un préaudit énergétique et servira de support d’introduction pour un éventuel audit approfondi. Ce projet permettra d’améliorer l’efficacité énergétique des bâtiments étudiés, une analyse complète de solutions envisageables sera proposée