Rhombomere rotation reveals that multiple mechanisms contribute to the segmental pattern of hindbrain neural crest migration

Hindbrain neural crest cells adjacent to rhombomeres 2 (r2), r4 and r6 migrate in a segmental pattern, toward the first, second and third branchial arches, respectively. Although all rhombomeres generate neural crest cells, those arising from r3 and r5 deviate rostrally and caudally (J. Sechrist, G. Serbedzija, T. Scherson, S. Fraser and M. Bronner-Fraser (1993) Development 118, 691–703). We have altered the rostrocaudal positions of the cranial neural tube, adjacent ectoderm/mesoderm or presumptive otic vesicle to examine tissue influences on this segmental migratory pattern. After neural tube rotation, labeled neural crest cells follow pathways generally appropriate for their new position after grafting. For example, when r3 and r4 were transposed, labeled r3 cells migrated laterally to the second branchial arch whereas labeled r4 cells primarily deviated caudally toward the second arch, with some cells moving rostrally toward the first. In contrast to r4 neural crest cells, transposed r3 cells leave the neural tube surface in a polarized manner, near the r3/4 border. Surprisingly, some labeled neural crest cells moved directionally toward small ectopic otic vesicles that often formed in the ectoderm adjacent to grafted r4. Similarly, they moved toward grafted or displaced otic vesicles. In contrast, surgical manipulation of the mesoderm adjacent to r3 and r4 had no apparent effects. Our results offer evidence that neural crest cells migrate directionally toward the otic vesicle, either by selective attraction or pathway-derived cues

Osuuskunta- ja osuustoiminnan edistäminen Suomessa

Opinnäytetyömme tavoitteena oli tutkia osuuskunta- ja osuustoimintaa Suomessa ja etsiä keinoja sen edistämiseen. EU-rahoitteinen Conventus-projekti toimii opinnäyt-teemme hankkeistajana. Teimme kaksi erillistä kyselytutkimusta, joiden tarkoituksena oli selvittää, kuinka osuuskunta- ja osuustoimintaa voitaisiin edistää Suomessa. Tutkimus toteutettiin sekä kvantitatiivisesti että kvalitatiivisesti. Teoreettinen viite-kehys muodostui kirjallisesta tutkimusaineistosta liittyen osuustoimintaan ja osuus-toiminnan arvoihin sekä periaatteisiin. Tiedonkeruumenetelmänä käytimme kahta erillistä sähköpostikyselyä. Sähköpostikysely lähetettiin 37 osuuskuntayrittäjälle ja toinen erillinen sähköposti-kysely lähetettiin 11 osuustoimintaa tukevalle henkilölle. Kyselyt laadittiin ja toteu-tettiin Datan analysointi- ja kyselytyökalu Webropolin avulla. Osuuskuntayrittäjien kyselyyn saimme 14 vastausta ja osuustoimintaa tukevien henkilöiden kyselyyn 5 vastausta. Kyselyiden tuloksia ja teoriataustaa vertaillessa huomasimme, että osuus-kuntien alkuperäinen tarkoitus eli yleinen hyvinvointi ja hyväntekeväisyys, on väis-tymässä tavallisen yrittämisen ja voitontavoittelun edeltä.The aim of our thesis was to investigate the cooperatives in Finland and to find ways to promote them. The EU-funded project Conventus is the assignor of our thesis work. We made two separate surveys, which were designed to determine how coop-eratives could be promoted in Finland. The research for our thesis was conducted both quantitatively and qualitatively. The questionnaires contained primarily open questions to enable use to find in-depth an-swers and information. The theoretical frame of reference consists of written research materials related to the cooperative movement and cooperative values and principles of operation. We used two separate e-mail surveys as a data collection method. One e-mail survey was sent to 37 co-operative entrepreneurs and another separate e-mail survey was sent to 11 supporters of cooperatives. The questionnaires of these surveys were drawn up, and were carried out with the data analysis and query tool Webropol. We received 14 answers from the cooperative enterprises and 5 replies from the supporters of cooperatives. After receiving the responses to our question-naires we compared them to the theoretical background of our thesis and found out that the original ideology of cooperatives, the welfare of members, has been forgot-ten and it has been replaced with normal business standards, making profit

Radiocarbon calibration beyond the dendrochronology range

The radiocarbon timescale has been calibrated by dendrochronology back to 11.8 ka cal BP, and extended to 14.8 ka cal BP using laminated marine sediments from the Cariaco Basin. Extension to nearly 23.5 ka cal BP is based on comparison between 14C and U-Th ages of corals. Recently, attempts to further extend the calibration curve to >40 kyr are based on laminated sediments from Lake Suigetsu, Japan, foraminifera in North Atlantic sediments, South African cave deposits, tufa from Spain, and stalagmites from the Bahamas. Here we compare these records with a new comparison curve obtained by 234U-230Th ages of aragonite deposited at Lake Lisan (the last Glacial Dead Sea). This comparison reveals broad agreement for the time interval of 20–32 ka cal BP, but the data diverge over other intervals. All records agree that Δ14C values range between ∼250–450‰ at 20–32 ka cal BP. For ages >32 ka cal BP, the Lake Suigetsu data indicate low Δ14C values of less than 200‰ and small shifts. The other records broadly agree that Δ14C values range between ∼250 and 600‰ at 32–39 ka cal BP. At ∼42 ka cal BP, the North Atlantic calibration shows low Δ14C values, while the corals, Lisan aragonites, and the Spanish tufa indicate a large deviations of 700–900‰. This age is slightly younger than recent estimates of the timing of the Laschamp Geomagnetic Event, and are consistent with increased 14C production during this event

Assessment of vocational guidance: the berufsbilder test

The object of this study is to assess informative possibilities of some technical indicators of the Test of Photos of Professions (BBT – Berufsbilder test), a projective method to clarify professional inclination, proposed by Martin Achtnich. This psychological evaluation technique is composed of 96 photos of professionals, performing various types of activities. The test subject classifies the photos into three groups: positive (agreeable), negative (disagreeable) and indifferent (neutral). Among those chosen positively, five preferences are chosen and a story is developed that includes them, an activity that is requested two times during the Vocational Guidance process: in the beginning (or middle) and at the end of the intervention. In this study, 160 stories were created by 80 youths, between 15 and 20 years of age, in public and private schools in a mid-sized Brazilian city. The stories were compared in three analytical categories: protagonist, professional conflict and resolution. The results were submitted to Wilcoxon nonparametric statistical analysis (p < .05), significant and relevant indicators of resolution being found in the process of occupational choice. This technical resource was shown, from this empirical evidence, to be promising for use in evaluation of intervention processes of Vocational Guidance.El objetivo de este estudio es evaluar las posibilidades informativas de algunos indicadores técnicos del Test de Fotos de Profesiones (BBT – Berufsbilder test), un método proyectivo para clarificar la inclinación profesional, propuesto por Martin Achtnich. Esta técnica de evaluación psicológica se compone de 96 fotografías de profesionales, realizando varios tipos de actividades. El sujeto del test clasifica las fotos en tres grupos: positivas (agradables), negativas (desagradables) e indiferentes (neutrales). Entre las fotos clasificadas positivamente, se eligen tres preferencias y se desarrolla una historieta que las incluya, actividad que es llevada a cabo dos veces durante el proceso de Orientación Vocacional: al principio (o en medio) y al final de la intervención. En este estudio, 80 jóvenes, de edades entre los 15 y los 20 años, procedentes de escuelas públicas y privadas de una ciudad de tamaño intermedio de Brasil, crearon 160 historietas. Se dividieron las historietas en tres categorías analíticas: protagonista, conflicto profesional, y resolución. Los resultados se sometieron al análisis estadístico no paramétrico Wilcoxon (p < .05), ), encontrando indicadores significativos y relevantes de haber llegado a resolución en el proceso de elección profesional. Debido a esta evidencia empírica, este recurso técnico se muestra prometedor para la evaluación de los procesos de intervención de Orientación Vocacional

Geologic context of geodetic data across a Basin and Range normal fault, Crescent Valley, Nevada

Geodetic strain and late Quaternary faulting in the Basin and Range province is distributed over a region much wider than historic seismicity, which is localized near the margins of the province. In the relatively aseismic interior, both the magnitude and direction of geodetic strain may be inconsistent with the Holocene faulting record. We document the best example of such a disagreement across the NE striking, ~55° NW dipping Crescent normal fault, where a NW oriented, 70 km geodetic baseline records contemporary shortening of ~2 mm/yr orthogonal to the fault trace. In contrast, our geomorphic, paleoseismic, and geochronologic analyses of the Crescent fault suggest that a large extensional rupture occurred during the late Holocene epoch. An excavation across the fault at Fourmile Canyon reveals that the most recent event occurred at 2.8 ± 0.1 ka, with net vertical tectonic displacement of 4.6 ± 0.4 m at this location, corresponding to the release of ~3 m of accumulated NW-SE extension. Measured alluvial scarp profiles suggest a minimum rupture length of 30 km along the range front for the event, implying a moment magnitude M_w of at least 6.6. No prior event occurred between ~2.8 ka and ~6.4 ± 0.1 ka, the ^(14)C calender age of strata near the base of the exposed section. Assuming typical slip rates for Basin and Range faults (~0.3 mm/yr), these results imply that up to one third, or ~1 m, of the extensional strain released in the previous earthquake could have reaccumulated across the fault since ~2.8 ka. However, the contemporary shortening implies that the fault is unloading due to a transient process, whose duration is limited to between 6 years (geodetic recording time) and 2.8 ka (the age of the most recent event). These results emphasize the importance of providing accurate geologic data on the timescale of the earthquake cycle in order to evaluate geodetic measurements

RIC-3 expression and splicing regulate nAChR functional expression

Effects of FL human RIC-3 vs. mouse FL on α7 nAChR functional expression in X. leavis oocytes. Results were normalized to currents recorded in oocytes expressing the respective receptors in the absence of RIC-3 in the same experiment. Each bar represents 10–20 oocytes from 2 to 3 independent X. laevis. The y-axis ordinates are on a log scale. * indicates a p value of less than 0.05; ** indicates a p value of less than 0.01. (PDF 714 kb

The deleted in brachydactyly B domain of ROR2 is required for receptor activation by recruitment of Src

The transmembrane receptor 'ROR2' resembles members of the receptor tyrosine kinase family of signalling receptors in sequence but its' signal transduction mechanisms remain enigmatic. This problem has particular importance because mutations in ROR2 are associated with two human skeletal dysmorphology syndromes, recessive Robinow Syndrome (RS) and dominant acting Brachydactyly type B (BDB). Here we show, using a constitutive dimerisation approach, that ROR2 exhibits dimerisation-induced tyrosine kinase activity and the ROR2 C-terminal domain, which is deleted in BDB, is required for recruitment and activation of the non-receptor tyrosine kinase Src. Native ROR2 phosphorylation is induced by the ligand Wnt5a and is blocked by pharmacological inhibition of Src kinase activity. Eight sites of Src-mediated ROR2 phosphorylation have been identified by mass spectrometry. Activation via tyrosine phosphorylation of ROR2 receptor leads to its internalisation into Rab5 positive endosomes. These findings show that BDB mutant receptors are defective in kinase activation as a result of failure to recruit Src

Excavation at Aguas Buenas, Robinson Crusoe Island, Chile, of a gunpowder magazine and the supposed campsite of Alexander Selkirk, together with an account of early navigational dividers

Excavations were undertaken of a ruined building at Aguas Buenas, identified as an 18th-century Spanish gunpowder magazine. Evidence was also found for the campsite of an early European occupant of the island. A case is made that this was Alexander Selkirk, a castaway here from 1704 to 1709. Selkirk was the model for Defoe’s Robinson Crusoe. A detailed discussion is given of a fragment of copper alloy identifi ed as being from a pair of navigational dividers

Depth electrode neurofeedback with a virtual reality interface

Invasive brain–computer interfaces (BCI) provide better signal quality in terms of spatial localization, frequencies and signal/noise ratio, in addition to giving access to deep brain regions that play important roles in cognitive or affective processes. Despite some anecdotal attempts, little work has explored the possibility of integrating such BCI input into more sophisticated interactive systems like those which can be developed with game engines. In this article, we integrated an amygdala depth electrode recorder with a virtual environment controlling a virtual crowd. Subjects were asked to down regulate their amygdala using the level of unrest in the virtual room as feedback on how successful they were. We report early results which suggest that users adapt very easily to this paradigm and that the timing and fluctuations of amygdala activity during self-regulation can be matched by crowd animation in the virtual room. This suggests that depth electrodes could also serve as high-performance affective interfaces, notwithstanding their strictly limited availability, justified on medical grounds only