Steerable optical tweezers for ultracold atom studies

We report on the implementation of an optical tweezer system for controlled transport of ultracold atoms along a narrow, static confinement channel. The tweezer system is based on high-efficiency acousto-optical deflectors and offers two-dimensional control over beam position. This opens up the possibility for tracking the transport channel when shuttling atomic clouds along the guide, forestalling atom spilling. Multiple clouds can be tracked independently by time-shared tweezer beams addressing individual sites in the channel. The deflectors are controlled using a multichannel direct digital synthesizer, which receives instructions on a sub-microsecond time scale from a field-programmable gate array. Using the tweezer system, we demonstrate sequential binary splitting of an ultracold $\rm^{87}Rb$ cloud into $2^5$ clouds.Comment: 4 pages, 5 figures, 1 movie lin

Measuring the local gravitational field using survival resonances in a dissipatively driven atom-optics system

We do a proof-of-principle demonstration of an atomic gravimeter based on survival resonances of dissipatively driven atoms. Exposing laser-cooled atoms to a sequence of near-resonant standing-wave light pulses reveals survival resonances when the standing-wave interference pattern accelerates. The resonant accelerations determine the local gravitational acceleration and we achieve a precision of 5 ppm with a drop distance less than 1 mm. The incisiveness of the resonances scales with the square of the drop time. Present results indicate that an appropriately designed atomic gravimeter based on survival resonances might be able to reach a precision of 1μGal with a 10-cm-high fountain. The relatively simple experimental construction of this technique may be of interest for a compact absolute atomic gravimeter

Quantum storage of heralded single photons in a praseodymium-doped crystal

We report on experiments demonstrating the reversible mapping of heralded single photons to long-lived collective optical atomic excitations stored in a Pr3+:Y2SiO5 crystal. A cavity-enhanced spontaneous down-conversion source is employed to produce widely nondegenerate narrow-band (≈2 MHz) photon pairs. The idler photons, whose frequency is compatible with telecommunication optical fibers, are used to herald the creation of the signal photons, compatible with the Pr3þ transition. The signal photons are stored and retrieved using the atomic frequency comb protocol. We demonstrate storage times up to 4.5 μs while preserving nonclassical correlations between the heralding and the retrieved photon. This is more than 20 times longer than in previous realizations in solid state devices, and implemented in a system ideally suited for the extension to spin-wave storage

Survival resonances in an atom-optics system driven by temporally and spatially periodic dissipation

We investigate laser-cooled atoms periodically driven by pulsed standing waves of light tuned close to an open atomic transition. This nonunitary system displays survival resonances for certain driving frequencies. The survival resonances emerge as a result of the matter-wave Talbot-Lau effect, similar to the Talbot effect causing quantum resonances in the atom optics δ-kicked rotor. Since the Talbot-Lau effect occurs for incoherent waves, the survival resonances can be observed using thermal atoms. A microlensing effect can enhance the height and incisiveness of the resonances. This may find applications in precision measurements

Caracterización de accesiones de garbanzo (Cicer arietinum L.) mediante descriptores morfo agronómicos cuantitativos en una colección del Banco de Germoplasma de la Universidad Nacional de Córdoba

El garbanzo (Cicer arietinum L) es la segunda leguminosa más cultivada en el mundo. La producción nacional está basada en pocos cultivares (Norteño, Chañaritos S-156, Kiara UNC-INTA, Felipe UNC-INTA, TUC 403, TUC 464 y TUC G 470). Debido a que el área cultivada está creciendo resulta importante disponer de nuevos materiales genéticos mejor adaptados a diferentes condiciones agroecológicas. Los objetivos del presente trabajo fueron caracterizar diferentes accesiones de garbanzo mediante descriptores morfo agronómicos cuantitativos, evaluar la variabilidad fenotípica de los materiales genéticos, determinar los descriptores que efectivamente contribuyen a la discriminación de las accesiones estudiadas y obtener una función canónica que permita clasificar nuevas accesiones según su origen. Se estudiaron 93 accesiones de garbanzo de diferentes orígenes utilizando diferentes aproximaciones estadísticas uni y multivariadas. La caracterización de las accesiones se realizó sobre cinco plantas, evaluando 17 descriptores morfo agronómicos. Los resultados de los estadísticos simples revelaron que las variables número de vainas por planta y peso de 100 semillas presentaron valores altos de CV. Los componentes de peso y volumen de semillas resultaron asociarse positivamente entre sí, pero negativamente con el número de vainas por planta. En el gráfico del perfil multivariado los caracteres que permitieron la mayor diferenciación de las accesiones fueron número de semillas por planta, número de vainas por planta y rendimiento por planta. En el análisis de conglomerados se dio la conformación de tres grupos diferenciados por las variables pesos de 100 semillas, altura de planta, número de vainas y semillas por planta. En el análisis de componentes principales se encontró que las tres primeras componentes principales explicaron el 66% de la variación total. En el C1 las variables que mayor contribución realizaron a la separación de los tipos de garbanzo fueron: número de vainas y semillas por planta, tamaño de semillas, peso de 100 semillas y altura de planta. Mediante el análisis discriminante se lograron detectar las variables morfo agronómicas que mejor discriminan (número de vainas y semillas por planta) las accesiones. Este estudio permitió concluir que existe una considerable variabilidad en todos los caracteres estudiados. De este modo podría ser utilizada la información para introducir germoplasma con mayor divergencia genética, seleccionando los progenitores con los mayores contrastes genéticos para los programas de mejora y ampliar la base genética para el garbanzo en Argentina.Chickpea (Cicer arietinum L.) is the second most important cultivated legume in the world. The production of Argentina is based on few cultivars (Norteño, Chañaritos S-156, Kiara UNC-INTA, Felipe UNC-INTA, TUC 403, TUC 464 and TUC G 470). As the cultivated area is increasing, it would be important to select new genetic materials better adapted to different agroecological conditions. The objectives of this research were to characterize different accessions of chickpea using quantitative morpho agronomic descriptors, to evaluate the phenotypic variability of genetic materials, determine the descriptors that effectively contribute to the discrimination of genetic materials of the accessions and obtain a canonical function that allows classifying new accessions according to its origin. The characterization of the accessions was carried out on five plants, evaluating 17 agronomic morpho descriptors in the field and laboratory. The results of descriptive statistics revealed that the pod numbers per plant and 100 seed weight variables presented high CV values. Seed weight and volume components were positively associated among them, but negatively correlated to pod numbers per plant. In the Multivariate Profile Analisys, the characters that allowed the greatest differentiation of accessions were seed numbers per plant, pod numbers per plant and yield per plant. In the cluster analysis, there were three groups differentiated by 100 seed weight, height of plant, pod numbers per plant and seed numbers per plant variables. In the principal component analysis, it was found that the first three main components accounted for 66% of the total variation. In C1 the variables that made the greatest contribution to the separation of chickpea types were: pod numbers per plant, seed numbers per plant, seed size, 100 seed weight and height of plant. Discriminant Analysis detected that the most discriminating morpho-agronomic variables were pod numbers per plant and seed numbers per plant. This study allows us to conclude that there is significant variation for all the characters studied. This variability can be used for safe introducing different germplasm and for selecting parents with the highest genetic contrasts for chickpea genetic improvement programs, and broadening the genetic bases of this crop in Argentina.EEA SaltaFil: Pocovi, Mariana Ines. Universidad Nacional de Salta. Facultad de Ciencias Naturales; ArgentinaFil: Collavino, Norma Graciela. Universidad Nacional de Salta. Facultad de Ciencias Naturales; ArgentinaFil: Farfan, Emilce Cristina. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Laboratorio de Marcadores Moleculares; ArgentinaFil: Carreras, Julia. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Fekete, Ana Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; ArgentinaFil: Pocovi, Mariana Ines. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentin

An environmental monitoring network for quantum gas experiments and devices

Quantum technology is approaching a level of maturity, recently demonstrated in space-borne experiments and in-field measurements, which would allow for adoption by non-specialist users. Parallel advancements made in microprocessor-based electronics and database software can be combined to create robust, versatile and modular experimental monitoring systems. Here, we describe a monitoring network used across a number of cold atom laboratories with a shared laser system. The ability to diagnose malfunction, unexpected or unintended behavior and passively collect data for key experimental parameters, such as vacuum chamber pressure, laser beam power, or resistances of important conductors, significantly reduces debugging time. This allows for efficient control over a number of experiments and remote control when access is limited

Therapeutic drug monitoring in adolescents with anorexia nervosa for safe treatment with adjunct olanzapine

Objective: Medication is commonly used in anorexia nervosa (AN) despite largely missing high grade evidence. Olanzapine (OLZ) is the best-evidenced substance used off-label in this group, with conflicting outcome regarding BMI, clinical and safety parameters. Therefore, it is important to strictly assure quality of treatment with OLZ in AN by using 'Therapeutic Drug Monitoring' according to AGNP-guidelines, including serum levels and adverse drug reactions (ADRs) to support safety for adolescents with AN and attempt to generate an initial age- and disorder-specific therapeutic reference range. Method: Sixty-five adolescents with AN (aged 10-18) treated with OLZ (98% female; 97.5% AN-restricting-type) were prospectively observed, ADRs reported, and correlations between dosage and serum levels measured at trough level were calculated, a preliminary therapeutic range defined. Results: Mean dosage of OLZ was 8.15 (SD: 2.91) mg and 0.19 (SD: 0.07) mg/kg respectively, average concentration was 26.57 (SD: 13.46) ng/mL. Correlation between daily dosage/dosage per kg and serum level was 0.72 (**p < 0.001)/0.65 (**p < 0.001), respectively. ADRs with impairment were rare (6.3%). 75% improved clinically (CGI). BMI increased significantly by 1.5 kg/m2 (t = 10.6, p < 0.001). A preliminary therapeutic reference range is 11.9 and 39.9 ng/mL. Conclusions: OLZ in the hands of specialists is a well-tolerated and safe treatment adjunct for adolescents with AN

Chronic Activation of γ2 AMPK Induces Obesity and Reduces β Cell Function.

Despite significant advances in our understanding of the biology determining systemic energy homeostasis, the treatment of obesity remains a medical challenge. Activation of AMP-activated protein kinase (AMPK) has been proposed as an attractive strategy for the treatment of obesity and its complications. AMPK is a conserved, ubiquitously expressed, heterotrimeric serine/threonine kinase whose short-term activation has multiple beneficial metabolic effects. Whether these translate into long-term benefits for obesity and its complications is unknown. Here, we observe that mice with chronic AMPK activation, resulting from mutation of the AMPK γ2 subunit, exhibit ghrelin signaling-dependent hyperphagia, obesity, and impaired pancreatic islet insulin secretion. Humans bearing the homologous mutation manifest a congruent phenotype. Our studies highlight that long-term AMPK activation throughout all tissues can have adverse metabolic consequences, with implications for pharmacological strategies seeking to chronically activate AMPK systemically to treat metabolic disease

2017 Research & Innovation Day Program

A one day showcase of applied research, social innovation, scholarship projects and activities.https://first.fanshawec.ca/cri_cripublications/1004/thumbnail.jp