SiPM used as fast Photon-Counting Module and for Multiphoton Detection

We demonstrate fast counting and multiphoton detection abilities of a Silicon Photo Multiplier (SiPM). In fast counting mode we are able to detect two consecutive photons separated by only 2.3 ns corresponding to 430 MHz. The counting efficiency for small optical intensities at a wavelength of 532 nm was found to be around 8.3% with a dark count rate of 50 kHz at T=-7 degrees Celsius. Using the SiPM in multiphoton detection mode, we find a good signal discrimination for different numbers of simultaneous detected photons.Comment: 11 pages, 13 figure

GHz QKD at telecom wavelengths using up-conversion detectors

We have developed a hybrid single photon detection scheme for telecom wavelengths based on nonlinear sum-frequency generation and silicon single-photon avalanche diodes (SPADs). The SPAD devices employed have been designed to have very narrow temporal response, i.e. low jitter, which we can exploit for increasing the allowable bit rate for quantum key distribution. The wavelength conversion is obtained using periodically poled Lithium niobate waveguides (W/Gs). The inherently high efficiency of these W/Gs allows us to use a continuous wave laser to seed the nonlinear conversion so as to have a continuous detection scheme. We also present a 1.27GHz qubit repetition rate, one-way phase encoding, quantum key distribution experiment operating at telecom wavelengths that takes advantage of this detection scheme. The proof of principle experiment shows a system capable of MHz raw count rates with a QBER less than 2% and estimated secure key rates greater than 100 kbit/s over 25 km.Comment: 12 pages, 7 figure

Superexpressão do precursor de rubisco para aumento da produtividade e tolerância à seca em arroz.

O objetivo deste trabalho foi gerar plantas de arroz geneticamente modificado (GM) superexpressando o gene precursor da subunidade Large da enzima Rubisco (rbcL), com a finalidade de aumentar a produtividade de grão sob irrigação normal e sob deficit hídrico

Performances de systèmes viticoles à faible niveau d’intrants phytopharmaceutiques dans le vignoble bordelais

Afin de répondre aux exigences de réduction de l'usage des produits phytosanitaires, ce projet vise à concevoir et à évaluer des systèmes viticoles qui en sont très économes. Ces systèmes, menés en agriculture conventionnelle ou biologique, sont basés essentiellement sur des leviers d'efficience de la lutte chimique pour la gestion des maladies et des ravageurs (règles de décision de traitement), et de substitution pour la maîtrise des adventices (travail du sol, couverts végétaux). Un autre type de système teste aussi le levier de la résistance variétale contre le mildiou et l'oïdium. Une évaluation multicritères de ces systèmes est effectuée pendant 5 ans au vignoble (réduction d’IFT, présence de résidus, maîtrise des bioagresseurs, atteinte des objectifs de rendement, coûts de production, temps de travail). Les résultats montrent que des systèmes basés essentiellement sur l'efficience permettent de réduire significativement l'IFT en maintenant des performances agronomiques et économiques satisfaisantes. Néanmoins, compte tenu d'une certaine prise de risque engendrée par ces systèmes, la diffusion des règles de décisions doit impliquer les viticulteurs. En viticulture biologique, il apparaît difficile de réduire les doses de cuivre et de soufre par rapport aux pratiques actuelles en maintenant des performances agronomiques stables. La mise en œuvre de variétés résistantes au mildiou et à l'oïdium permet de réduire l’IFT de 90 % par rapport aux références régionales

Effects of sulfate starvation on agar polysaccharides of Gracilaria species (Gracilariaceae, Rhodophyta) from Morib, Malaysia

The effects of sulfate starvation on the agar characteristics of Gracilaria species was investigated by culturing two red algae from Morib, Malaysia, Gracilaria changii and Gracilaria salicornia in sulfate-free artificial seawater for 5 days. The seaweed samples were collected in October 2012 and March 2013, periods which have significant variation in the amount of rainfall. The agar yields were shown to be independent of sulfate availability, with only 0.60–1.20 % increment in treated G. changii and 0.31–1.40 % increment in treated G. salicornia while their gel strengths did not increase significantly (approximately 5–7 %) after sulfate starvation for both species. The gelling and melting temperatures did not vary between control and treated samples from both species, except for the treated G. changii collected in March 2013. The gel syneresis index of G. salicornia collected in March 2013 increased significantly after sulfate deprivation. Sulfate starvation introduced some variations in the content of 3, 6-anhydrogalactose and total sulfate esters, but the changes did not have a pronounced effect on the physical properties of agar

Motor signatures of emotional reactivity in frontotemporal dementia

Automatic motor mimicry is essential to the normal processing of perceived emotion, and disrupted automatic imitation might underpin socio-emotional deficits in neurodegenerative diseases, particularly the frontotemporal dementias. However, the pathophysiology of emotional reactivity in these diseases has not been elucidated. We studied facial electromyographic responses during emotion identification on viewing videos of dynamic facial expressions in 37 patients representing canonical frontotemporal dementia syndromes versus 21 healthy older individuals. Neuroanatomical associations of emotional expression identification accuracy and facial muscle reactivity were assessed using voxel-based morphometry. Controls showed characteristic profiles of automatic imitation, and this response predicted correct emotion identification. Automatic imitation was reduced in the behavioural and right temporal variant groups, while the normal coupling between imitation and correct identification was lost in the right temporal and semantic variant groups. Grey matter correlates of emotion identification and imitation were delineated within a distributed network including primary visual and motor, prefrontal, insular, anterior temporal and temporo-occipital junctional areas, with common involvement of supplementary motor cortex across syndromes. Impaired emotional mimesis may be a core mechanism of disordered emotional signal understanding and reactivity in frontotemporal dementia, with implications for the development of novel physiological biomarkers of socio-emotional dysfunction in these diseases

What’s retinoic acid got to do with it? Retinoic acid regulation of the neural crest in craniofacial and ocular development

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151310/1/dvg23308.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151310/2/dvg23308_am.pd

Atributos físicos e químicos de solos em áreas de barragens subterrâneas no agreste e no planalto da Borborema, Estado da Paraíba.

O presente trabalho fez uma avaliação da qualidade física e química do solo de quatro barragens subterrâneas, em duas regiões fisiográficas do Estado da Paraíba, visando fornecer informações que contribuirão para o melhor uso e manejo, consequentemente obtenção de melhores produções.bitstream/item/162907/1/CircTec-47-Atributos-barragens.pd