2,569 research outputs found
The Goddard Project
The goal of this project was to design and build a robotic dog modeled after Goddard from the 2001 television series, The Adventures of Jimmy Neutron Boy Genius. Sheet metal was used for the body of the robot in order to keep the frame lightweight. Goddard travels on two wheels powered by electric motors and two caster wheels. The robot utilizes a Raspberry Pi as its master device and an Arduino Uno in order to control the robot. Essentially, Goddard acts and behaves like an ordinary dog from barking, to moving around, to being a great companion and friend. In addition, Goddard also has access to the extensive knowledge of the Wolfram Alpha database and can be controlled over a wireless internet connection using a keyboard or voice controls. This project was successfully presented and demonstrated at the 2014 University of New Hampshire Undergraduate Research Conference and received an Award of Excellence
The pol3-t Hyperrecombination Phenotype and DNA Damage-Induced Recombination in Saccharomyces cerevisiae Is RAD50 Dependent
The DNA polymerase δ (POL3/CDC2) allele pol3-t of Saccharomyces cerevisiae has previously been shown to be sensitive to methylmethanesulfonate (MMS) and has been proposed to be involved in base excision repair. Our results, however, show that the pol3-t mutation is synergistic for MMS sensitivity with MAG1, a known base excision repair gene, but it is epistatic with rad50Δ, suggesting that POL3 may be involved not only in base excision repair but also in a RAD50 dependent function. We further studied the interaction of pol3-t with rad50Δ by examining their effect on spontaneous, MMS-, UV-, and ionizing radiation-induced intrachromosomal recombination. We found that rad50Δ completely abolishes the elevated spontaneous frequency of intrachromosomal recombination in the pol3-t mutant and significantly decreases UV- and MMS-induced recombination in both POL3 and pol3-t strains. Interestingly, rad50Δ had no effect on γ-ray-induced recombination in both backgrounds between 0 and 50 Gy. Finally, the deletion of RAD50 had no effect on the elevated frequency of homologous integration conferred by the pol3-t mutation. RAD50 is possibly involved in resolution of replication forks that are stalled by mutagen-induced external DNA damage, or internal DNA damage produced by growing the pol3-t mutant at the restrictive temperature
Holographic second laws of black hole thermodynamics
Recently, it has been shown that for out-of-equilibrium systems, there are
additional constraints on thermodynamical evolution besides the ordinary second
law. These form a new family of second laws of thermodynamics, which are
equivalent to the monotonicity of quantum R\'enyi divergences. In black hole
thermodynamics, the usual second law is manifest as the area increase theorem.
Hence one may ask if these additional laws imply new restrictions for
gravitational dynamics, such as for out-of-equilibrium black holes? Inspired by
this question, we study these constraints within the AdS/CFT correspondence.
First, we show that the R\'enyi divergence can be computed via a Euclidean path
integral for a certain class of excited CFT states. Applying this construction
to the boundary CFT, the R\'enyi divergence is evaluated as the renormalized
action for a particular bulk solution of a minimally coupled gravity-scalar
system. Further, within this framework, we show that there exist transitions
which are allowed by the traditional second law, but forbidden by the
additional thermodynamical constraints. We speculate on the implications of our
findings.Comment: 81 pages, 19 figures; v2: clarifications and reference added, minor
typos corrected, published versio
Observation of crystallization slowdown in supercooled para-hydrogen and ortho-deuterium quantum liquid mixtures
We report a quantitative experimental study of the crystallization kinetics
of supercooled quantum liquid mixtures of para-hydrogen (pH) and
ortho-deuterium (oD) by high spatial resolution Raman spectroscopy of
liquid microjets. We show that in a wide range of compositions the
crystallization rate of the isotopic mixtures is significantly reduced with
respect to that of the pure substances. To clarify this behavior we have
performed path-integral simulations of the non-equilibrium pH-oD liquid
mixtures, revealing that differences in quantum delocalization between the two
isotopic species translate into different effective particle sizes. Our results
provide first experimental evidence for crystallization slowdown of quantum
origin, offering a benchmark for theoretical studies of quantum behavior in
supercooled liquids.Comment: 6 pages, 3 figure
Visual field loss and vision-related quality of life in the Italian Primary Open Angle Glaucoma Study.
The aim of this study was to examine the relationship between visual field (VF) loss, vision-related quality of life (QoL) and glaucoma-related symptoms in a large cohort of primary open angle glaucoma (POAG) patients. POAG patients with or without VF defects or "glaucoma suspect" patients were considered eligible. QoL was assessed using the validated versions of the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and glaucoma-related symptoms were assessed using the Glaucoma Symptom Scale (GSS). Patients were classified as having VF damage in one eye (VFD-1), both eyes (VFD-2), or neither eye (VFD-0). 3227 patients were enrolled and 2940 were eligible for the analysis. 13.4% of patients were classified in the VFD-0, 23.7% in the VFD-1, and 62.9% in the VFD-2 group. GSS visual symptoms domain (Func-4) and GSS non-visual symptoms domain (Symp-6) scores were similar for the VFD-0 and VFD-1 groups (p = 0.133 and p = 0.834 for Func-4 and Symp-6, respectively). VFD-0 group had higher scores than VFD-2 both in Func-4 (p < 0.001) and Symp-6 domains (p = 0.035). Regarding the NEI-VFQ-25, our data demonstrated that bilateral VF defects are associated with vision-related QoL deterioration, irrespective of visual acuity
Knowledge, attitudes and practices towards malaria diagnostics among healthcare providers and healthcare-seekers in Kondoa district, Tanzania: a multi-methodological situation analysis.
BACKGROUND
Despite the large-scale rollout of malaria rapid diagnostic tests (RDTs) in Tanzania, many healthcare providers (HCPs) continue using blood film microscopy (BFM) and clinical examination to diagnose malaria, which can increase the risk of mal-diagnosis and over-prescribing of anti-malarials. Patients disregarding negative test results and self-treating exacerbate the problem. This study explored the knowledge, attitudes and practices of HCPs and healthcare-seekers regarding RDTs in comparison to BFM testing.
METHODS
A situational analysis was, therefore, conducted in Kondoa District, Dodoma Region, Tanzania. A multi-methodological approach was adopted including (i) a health facility inventory and screening of logbooks from May 2013 to April 2014 with 77,126 patient entries from 33 health facilities; (ii) a survey of 40 HCPs offering malaria services; and iii) a survey of 309 randomly selected household members from the facilities' catchment area. Surveys took place in April and May 2014.
RESULTS
Health facility records revealed that out of 77,126 patient entries, 22% (n = 17,235) obtained a malaria diagnosis. Of those, 45% were made with BFM, 33% with RDT and 22% with clinical diagnosis. A higher rate of positive diagnoses was observed with BFM compared with RDT (71% vs 14%). In the HCP survey, 48% preferred using BFM for malaria testing, while 52% preferred RDT. Faced with a negative RDT result for a patient presenting with symptoms typical for malaria, 25% of HCPs stated they would confirm the result with a microscopy test, 70% would advise or perform a clinical diagnosis and 18% would prescribe anti-malarials. Interviews with household members revealed a preference for microscopy testing (58%) over RDT (23%), if presented with malaria symptoms. For participants familiar with both tests, a second opinion was desired in 45% after a negative microscopy result and in 90% after an RDT.
CONCLUSIONS
Non-adherence to negative diagnostics by HCPs and patients continues to be a concern. Frequent training and supportive supervision for HCPs diagnosing and treating malaria and non-malaria febrile illnesses is essential to offer quality services that can instil confidence in HCPs and patients alike. The introduction of new diagnostic devices should be paired with context-specific behaviour change interventions targeting healthcare-seekers and healthcare providers
First law of holographic complexity
We investigate the variation of holographic complexity for two nearby target
states. Based on Nielsen's geometric approach, we find the variation only
depends on the end point of the optimal trajectory, a result which we designate
the first law of complexity. As an example, we examine the complexity=action
conjecture when the AdS vacuum is perturbed by a scalar field excitation, which
corresponds to a coherent state. Remarkably, the gravitational contributions
completely cancel and the final variation reduces to a boundary term coming
entirely from the scalar field action. Hence the null boundary of
Wheeler-DeWitt patch appears to act like the "end of the quantum circuit".Comment: 7 pages + supplemental material, 2 figures; v2: clarifications and
reference added, published versio
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Electronic structure of aqueous solutions: Bridging the gap between theory and experiments
Predicting the electronic properties of aqueous liquids has been a long-standing challenge for quantum mechanical methods. However, it is a crucial step in understanding and predicting the key role played by aqueous solutions and electrolytes in a wide variety of emerging energy and environmental technologies, including battery and photoelectrochemical cell design. We propose an efficient and accurate approach to predict the electronic properties of aqueous solutions, on the basis of the combination of first-principles methods and experimental validation using state-of-the-art spectroscopic measurements. We present results of the photoelectron spectra of a broad range of solvated ions, showing that first-principles molecular dynamics simulations and electronic structure calculations using dielectric hybrid functionals provide a quantitative description of the electronic properties of the solvent and solutes, including excitation energies. The proposed computational framework is general and applicable to other liquids, thereby offering great promise in understanding and engineering solutions and liquid electrolytes for a variety of important energy technologies
Aspects of The First Law of Complexity
We investigate the first law of complexity proposed in arXiv:1903.04511,
i.e., the variation of complexity when the target state is perturbed, in more
detail. Based on Nielsen's geometric approach to quantum circuit complexity, we
find the variation only depends on the end of the optimal circuit. We apply the
first law to gain new insights into the quantum circuits and complexity models
underlying holographic complexity. In particular, we examine the variation of
the holographic complexity for both the complexity=action and complexity=volume
conjectures in perturbing the AdS vacuum with coherent state excitations of a
free scalar field. We also examine the variations of circuit complexity
produced by the same excitations for the free scalar field theory in a fixed
AdS background. In this case, our work extends the existing treatment of
Gaussian coherent states to properly include the time dependence of the
complexity variation. We comment on the similarities and differences of the
holographic and QFT results.Comment: 108 pages, 15 figures; v2: references adde
Música y cine: musicalización del cortometraje <i>Memorias</i>
A partir del año 2019, los departamentos de Música y Artes Audiovisuales de la Facultad de Artes (FdA-UNLP) vienen llevando adelante un proyecto de producción en colaboración, mediante las cátedras de Música Incidental y Realización 4. La situación de pandemia que hemos padecido, paradójicamente afianzó los vínculos de aquel momento inicial.
El presente trabajo narra los distintos momentos de la elaboración de la música de un cortometraje producido durante 2021. En él, se relata cómo estudiantes músicos y cineastas comenzaron a vincularse y luego a trabajar juntos, tomando las decisiones necesarias para lograr un producto digno de exposición.
Mediante la difusión de estos procesos de trabajo, esperamos hacer un aporte como antecedente hacia una producción audiovisual integral, vinculada con nuestra identidad: universitaria, platense, nacional.Facultad de Arte
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