3,605 research outputs found
TESTING FOR DIFFERENCES IN CONSUMER ACCEPTANCE OF IDENTICALLY APPEARING POTATO VARIETIES
Like many other vegetables, potatoes are marketed by type (russet, round white, red), rather than by variety (Burbak, Katahdin, Pontiac). Although varieties of the same type have similar outward appearances, they are also known to have different internal and cooking characteristics. There has been considerable controversy over the need for variety identification promotion in the potato industry. A consumer response study that distinguished between user satisfaction with different potato varieties was viewed as a step toward resolving this issue.Consumer/Household Economics,
Ultrasonic Thermometry for Recession Measurements in Ablative Materials
Recent developments in ultrasonic instrumentation & sensors, improved signal processing, and high speed data acquisition have rekindled interest in ultrasonic thermometry and made temperature localization feasible and economically attractive to a wider range of applications. Ultrasound-based temperature measurements offer several advantages: they are non-intrusive, have high temporal response, isolate the sensor from explosive or chemically harsh environments and do not adversely influence thermal transport. Ultrasonic thermometry techniques rely on precise measurements of ultrasonic time-of-flight (ToF) which forms the basis for many applications including measurements of flow, heat flux, temperature, ablation and strain. In this report, we characterize the ultrasonic propagation characteristics of several ablative materials. Properties relevant to ultrasonic thermometry include backscattering properties, attenuation coefficient, ultrasonic velocity, and velocity-temperature coefficient. We will present preliminary experiments directed at developing ultrasonic methods for simultaneous temperature and recession measurements on ablators. Various approaches to measuring recession, heat flux, and internal temperature profiles in ablators will be described
Convergence Conditions for Random Quantum Circuits
Efficient methods for generating pseudo-randomly distributed unitary
operators are needed for the practical application of Haar distributed random
operators in quantum communication and noise estimation protocols. We develop a
theoretical framework for analyzing pseudo-random ensembles generated through a
random circuit composition. We prove that the measure over random circuits
converges exponentially (with increasing circuit length) to the uniform (Haar)
measure on the unitary group and describe how the rate of convergence may be
calculated for specific applications.Comment: 4 pages (revtex), comments welcome. v2: reference added, title
changed; v3: published version, minor changes, references update
Quantum Process Tomography of the Quantum Fourier Transform
The results of quantum process tomography on a three-qubit nuclear magnetic
resonance quantum information processor are presented, and shown to be
consistent with a detailed model of the system-plus-apparatus used for the
experiments. The quantum operation studied was the quantum Fourier transform,
which is important in several quantum algorithms and poses a rigorous test for
the precision of our recently-developed strongly modulating control fields. The
results were analyzed in an attempt to decompose the implementation errors into
coherent (overall systematic), incoherent (microscopically deterministic), and
decoherent (microscopically random) components. This analysis yielded a
superoperator consisting of a unitary part that was strongly correlated with
the theoretically expected unitary superoperator of the quantum Fourier
transform, an overall attenuation consistent with decoherence, and a residual
portion that was not completely positive - although complete positivity is
required for any quantum operation. By comparison with the results of computer
simulations, the lack of complete positivity was shown to be largely a
consequence of the incoherent errors during the quantum process tomography
procedure. These simulations further showed that coherent, incoherent, and
decoherent errors can often be identified by their distinctive effects on the
spectrum of the overall superoperator. The gate fidelity of the experimentally
determined superoperator was 0.64, while the correlation coefficient between
experimentally determined superoperator and the simulated superoperator was
0.79; most of the discrepancies with the simulations could be explained by the
cummulative effect of small errors in the single qubit gates.Comment: 26 pages, 17 figures, four tables; in press, Journal of Chemical
Physic
A Dichotomous Role for Nitric Oxide During Acute Toxoplasma gondii Infection in Mice
Production of nitric oxide by macrophages is believed to be an important microbicidal mechanism for a variety of intracellular pathogens, including Toxoplasma gondii. Mice with a targeted disruption of the inducible nitric oxide synthase gene (iNOS) were infected orally with T. gondii tissue cysts. Time to death was prolonged compared with parental controls. Histologic analysis of tissue from infected mice showed scattered small foci of inflammation with parasites in various tissues of iNOS−/− mice, whereas tissue from the parental C57BL/6 mice had more extensive tissue inflammation with few visible parasites. In particular, extensive ulceration and necrosis of distal small intestine and fatty degeneration of the liver was seen in the parental mice at day 7 postinfection, as compared with the iNOS−/− mice where these tissues appeared normal. Serum interferon γ and tumor necrosis factor α levels postinfection were equally elevated in both mouse strains. Treatment of the parental mice with a NO synthase inhibitor, aminoguanidine, prevented early death in these mice as well as the hepatic degeneration and small bowel necrosis seen in acutely infected control parentals. These findings indicate that NO production during acute infection with T. gondii can kill intracellular parasites but can be detrimental, even lethal, to the host
Experimental Implementation of the Quantum Baker's Map
This paper reports on the experimental implementation of the quantum baker's
map via a three bit nuclear magnetic resonance (NMR) quantum information
processor. The experiments tested the sensitivity of the quantum chaotic map to
perturbations. In the first experiment, the map was iterated forward and then
backwards to provide benchmarks for intrinsic errors and decoherence. In the
second set of experiments, the least significant qubit was perturbed in between
the iterations to test the sensitivity of the quantum chaotic map to applied
perturbations. These experiments are used to investigate previous predicted
properties of quantum chaotic dynamics.Comment: submitted to PR
Metastatic prostate cancer masquerading clinically and radiologically as a primary caecal carcinoma
BACKGROUND: Prostatic carcinoma is the second most common cause of cancer-related deaths in males in the West. Approximately 20% of patients present with metastatic disease. We describe the case of a patient with metastatic prostate cancer to the bowel presenting clinically and radiologically as a primary caecal cancer. CASE PRESENTATION: A 72 year-old man presented with abdominal discomfort and a clinically palpable caecal mass and a firm nodule on his thigh, the latter behaving clinically and radiologically as a lipoma. Computed tomographic (CT) scan showed a luminally protuberant caecal mass with regional nodal involvement. The patient was being treated (Zoladex(®)) for prostatic cancer diagnosed 6 years previously and was known to have bony metastases. On admission his PSA was 245.4 nmol/ml. The patient underwent a right hemicolectomy. Histology showed a poorly differentiated adenocarcinoma which was PSA positive, confirming metastatic prostatic adenocarcinoma to the caecum. The patient underwent adjuvant chemotherapy and is free from recurrence a year later. CONCLUSION: Metastasis of prostatic carcinoma to the bowel is a very rare occurrence and presents a challenging diagnosis. The diagnosis is supported by immunohistochemistry for PSA. The treatment for metastatic prostate cancer is mainly palliative
A tailored Internet of Things lighting solution to support circadian rhythms and wellbeing for people living with dementia
Light is a requirement for setting and maintaining the body’s circadian rhythm, however our knowledge of the spectral content, timing and duration of lighting exposure for the indoors is not well defined. For people living with dementia, this knowledge gap is important to address since they experience more heavily disrupted circadian rhythms, which can heighten symptoms of sundowning, agitation, low mood and poor sleep quality. This paper focuses on the required design aspects for a dynamic lighting and sensing device tailored towards supporting the wellbeing of people living with dementia. The authors discuss the current understanding of lighting for health, identify the gaps to be addressed and propose the design and research protocol for an indoor lighting and sensing solution. The device is currently deployed within a care home and analysis of results is forthcoming
- …