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We describe Urukul, a frequency synthesizer based on direct digital synthesis (DDS), optimized for wave generate control in atomic, molecular and optical (AMO) physics experiments. The Urukul module is a part of the Sinara family of modular, open-source hardware designed for the ARTIQ quantum operating system. The Urukul has 4-channel, sub-Hz frequency resolution, controlled phase steps and accurate output amplitude control. The module is available in two population variants. This paper presents Urukul module construction and obtained characteristics.

The Sinara hardware platform is a modular, opensource measurement and control system dedicated to quantum applications that require hard real-time performance. The hardware is controlled and managed by the ARTIQ, open-source software that provides nanosecond timing resolution and submicrosecond latency. The Sampler is a general-purpose precision ADC sampling unit with programmable gain and configurable interface. It is used in numerous applications like laser frequency and intensity servo. This paper presents the Sampler module construction and obtained characteristics.

Chalcodermus aeneus Boheman (Coleoptera: Curculionidae) has been the most destructive insect pest of black-eyed peas or cowpeas, Vigna unguiculata L. (Fabales: Fabaceae), over the last century in the southeastern United States. The historical distribution of this semitropical pest suggests the likelihood that diapause plays a key role in the overwintering success in parts of the United States. However, this report is the first to document biological evidence for diapause in C. aeneus. Our study assessed larval emergence from cowpea pods in the summer to fall growing seasons, egg development in female adults over the first (summer) and second (fall) generations, and adult emergence from infested soil after the first and second generations.There was a clear reduction in larval emergence from summer to fall. Egg and follicle development in female C. aeneus dropped off dramatically by September of each year.There was an extended emergence pattern of weevil adults from the soil in the fall as compared to the summer generation. Any future regional management of cowpea curculio will have to take into account the ability of this insect to diapause, thereby increasing its capacity to overwinter in regions where the cowpea crop, a warm-season, semitropical plant, is terminated with winter freezing temperatures.

This thesis is concerned with the development of an intermediate magnetic field \"clock-qubit\" in 43Ca+ at 146G and techniques to manipulate this qubit using microwaves and lasers. While 43Ca+ has previously been used as a qubit, its relatively complicated level structure - with a nuclear spin of 7/2 and low-lying D-states -- makes cooling it in the intermediate field an intimidating prospect. As a result, previous experiments have used small magnetic fields of a few gauss where coherence times are limited and off-resonant excitation is a significant source of experimental error. We demonstrate a simple scheme that allows 43Ca+ to be cooled in the intermediate field without any additional experimental complexity compared with low fields. Using the clock-qubit, we achieve a coherence time of T*2 = 50 (10)s - the longest demonstrated in any single qubit. We also demonstrate a combined state preparation and measurement error of 6.8(6)x 10-4 - the lowest achieved for a hyperfine trapped ion qubit [NVG+13] - and single-qubit logic gates with average errors of 1.0(3) x 10-6 - more than an order of magnitude better than the previous record [BWC+11]. These results represent the state-of-the-art in the field of single-qubit control. Moreover, we achieve them all in a single scalable room-temperature ion trap using experimentally robust techniques and without relying on the use of narrow-linewidth lasers, magnetic field screening or dynamical decoupling techniques. We also present work on a recent scheme [OWC+11] to drive two-qubit gates using microwaves. We have constructed an ion trap with integrated microwave circuitry to perform these gates. Using this trap, we have driven motional sideband transitions, demonstrating the spin-motion coupling that underlies the two-qubit gate. We present an analysis of likely sources of experimental error during a future two-qubit gate and the design and preliminary characterisation of apparatus to minimise the main error contributions. Using this apparatus, we hope to perform a two-qubit gate in the near future.

This thesis is concerned with the development of an intermediate magnetic field \"clock-qubit\" in 43Ca+ at 146G and techniques to manipulate this qubit using microwaves and lasers. While 43Ca+ has previously been used as a qubit, its relatively complicated level structure - with a nuclear spin of 7/2 and low-lying D-states -- makes cooling it in the intermediate field an intimidating prospect. As a result, previous experiments have used small magnetic fields of a few gauss where coherence times are limited and off-resonant excitation is a significant source of experimental error. We demonstrate a simple scheme that allows 43Ca+ to be cooled in the intermediate field without any additional experimental complexity compared with low fields. Using the clock-qubit, we achieve a coherence time of T*2 = 50 (10)s - the longest demonstrated in any single qubit. We also demonstrate a combined state preparation and measurement error of 6.8(6)x 10-4 - the lowest achieved for a hyperfine trapped ion qubit [NVG+13] - and single-qubit logic gates with average errors of 1.0(3) x 10-6 - more than an order of magnitude better than the previous record [BWC+11]. These results represent the state-of-the-art in the field of single-qubit control. Moreover, we achieve them all in a single scalable room-temperature ion trap using experimentally robust techniques and without relying on the use of narrow-linewidth lasers, magnetic field screening or dynamical decoupling techniques. We also present work on a recent scheme [OWC+11] to drive two-qubit gates using microwaves. We have constructed an ion trap with integrated microwave circuitry to perform these gates. Using this trap, we have driven motional sideband transitions, demonstrating the spin-motion coupling that underlies the two-qubit gate. We present an analysis of likely sources of experimental error during a future two-qubit gate and the design and preliminary characterisation of apparatus to minimise the main error contributions. Using this apparatus, we hope to perform a two-qubit gate in the near future.

The goal of this thesis was to characterize the nonlinear response properties of the perforant path projection from the entorhinal cortex to granule cells in open-loop conditions, i.e., in the absence of all other modulatory influences mediated by interneurons and connections between subsystems. These studies made use of the transverse, in vitro hippocampal slice to investigate open-loop conditions because granule cells can be activated by perforant path stimulation, but multisynaptic feedback connections involving other hippocampal subsystems are eliminated in this preparation. However, many different populations of interneurons reside in the dentate gyrus and the other subsystems of the hippocampus that could influence granule cell nonlinear response properties in a slice preparation. For example, GABAergic neurons are abundant in all layers of the dentate gyrus, and both GABA$\\sb{\\rm A}$ and GABA$\\sb{\\rm B}$ receptors are activated by stimulation of the perforant path in a slice preparation. The influence of GABAergic interneurons was pharmacologically eliminated with the use of the GABA$\\sb{\\rm A}$ antagonist, bicuculline, and the GABA$\\sb{\\rm B}$ antagonist, saclofen. To eliminate non-GABAergic populations of interneurons, a portion of the dentate gyrus was isolated from the slice preparation. The isolation procedure had no effect on granule cell nonlinear response properties, demonstrating that interneurons in the deep hilus, CA1 and CA3 do not influence granule cell input/output properties. Finally, to determine the influence of interneurons with axons that project in the longitudinal axis of the hippocampus, granule cell response properties in 600 $\\mu$m and 300 $\\mu$m slices were compared. Based on these studies, the optimal open-loop conditions for examining the contribution of intrinsic properties of granule cells to their nonlinear response characteristics consists of 300 $\\mu$m slices in the presence of GABA antagonists. (Abstract shortened with permission of author.)

A good part of the population is definitely diet-conscious these days.

It must be rugged to be a grade-school teacher in this day and age. This is the time of year they meet 40 or 60 strange little humans, each with his or her own plan.

Sepsis, an amplified immune response to systemic infection, is characterized by a transient cytokine storm followed by chronic immune dysfunction. Consequently, sepsis survivors are highly susceptible to newly introduced infections, suggesting sepsis can influence the function and composition of the naïve CD8 T cell pool and resulting pathogen-induced primary CD8 T cell responses. Here, we explored the extent to which sepsis induces phenotypic and functional changes within the naïve CD8 T cell pool. To interrogate this, the cecal ligation and puncture (CLP) mouse model of polymicrobial sepsis was used. In normal, non-septic mice, we show type-I interferon (IFN I)-mediated signaling plays an important role in driving the phenotypic and functional heterogeneity in the naïve CD8 T cell compartment leading to increased representation of Ly6C + naïve CD8 T cells. In response to viral infection after sepsis resolution, naïve Ly6C + CD8 T cells generated more primary effector and memory CD8 T cells with slower conversion to a central memory CD8 T cell phenotype (Tcm) than Ly6C - naïve CD8 T cells. Importantly, as a potent inducer of cytokine storm and IFN I production, sepsis leads to increased representation of Ly6C + naïve CD8 T cells that maintained their heightened ability to respond (i.e., effector and memory CD8 T cell accumulation and cytokine production) to primary LCMV infection. Lastly, longitudinal analyses of peripheral blood samples obtained from septic patients revealed profound changes in CD8 T cell subset composition and frequency compared to healthy controls. Thus, sepsis has the capacity to alter the composition of naïve CD8 T cells, directly influencing primary CD8 T cell responses to newly introduced infections.

Chronically infected mice upregulate expression of inhibitory molecules on exhausted T cells. Harty and colleagues report similar findings in human patients with malaria and show that blockade of the inhibitory receptors PD-L1 and LAG-3 restores antimalaria responses in mice. Infection of erythrocytes with Plasmodium species induces clinical malaria. Parasite-specific CD4 + T cells correlate with lower parasite burdens and severity of human malaria and are needed to control blood-stage infection in mice. However, the characteristics of CD4 + T cells that determine protection or parasite persistence remain unknown. Here we show that infection of humans with Plasmodium falciparum resulted in higher expression of the inhibitory receptor PD-1 associated with T cell dysfunction. In vivo blockade of the PD-1 ligand PD-L1 and the inhibitory receptor LAG-3 restored CD4 + T cell function, amplified the number of follicular helper T cells and germinal-center B cells and plasmablasts, enhanced protective antibodies and rapidly cleared blood-stage malaria in mice. Thus, chronic malaria drives specific T cell dysfunction, and proper function can be restored by inhibitory therapies to enhance parasite control.