14 research outputs found
First results from the HAYSTAC axion search
The axion is a well-motivated cold dark matter (CDM) candidate first
postulated to explain the absence of violation in the strong interactions.
CDM axions may be detected via their resonant conversion into photons in a
"haloscope" detector: a tunable high- microwave cavity maintained at
cryogenic temperature, immersed a strong magnetic field, and coupled to a
low-noise receiver.
This dissertation reports on the design, commissioning, and first operation
of the Haloscope at Yale Sensitive to Axion CDM (HAYSTAC), a new detector
designed to search for CDM axions with masses above . I
also describe the analysis procedure developed to derive limits on axion CDM
from the first HAYSTAC data run, which excluded axion models with two-photon
coupling , a
factor of 2.3 above the benchmark KSVZ model, over the mass range .
This result represents two important achievements. First, it demonstrates
cosmologically relevant sensitivity an order of magnitude higher in mass than
any existing direct limits. Second, by incorporating a dilution refrigerator
and Josephson parametric amplifier, HAYSTAC has demonstrated total noise
approaching the standard quantum limit for the first time in a haloscope axion
search.Comment: Ph.D. thesis. 346 pages, 58 figures. A few typos corrected relative
to the version submitted to ProQues
Endoscopic Cryotherapy of Lung and Bronchial Tumors: A Systematic Review
Background/Aims: We made a systematic review and evaluation of endoscopic cryotherapy of endobronchial tumors, investigating safety and efficacy. Methods: Qualified studies regarding endoscopic cryotherapy of lung tumors were systemically evaluated using available databases according to predefined criteria. Results: In total, 16 publications were included in the final assessment. A narrative synthesis was performed because a formal meta-analysis was not viable due to the lack of controlled studies and study heterogeneity. Overall success rates for significant recanalization of the obstruction were approximately 80%, although they varied, depending on disease status in the patient population. Complications from the procedure developed in 0-11.1% of cases, most of which were minor and controlled by conservative management. Although limited data were available on comprehensive functional assessment, some studies showed that respiratory symptoms, pulmonary function tests, and performance status were significantly improved. Conclusions: Endoscopic cryotherapy was found to be a safe and useful procedure in the management of endobronchial tumors although its efficacy and appropriate indications have yet to be determined in well-designed controlled studies
Baseline characteristics of the study patients and nodules.
<p>Baseline characteristics of the study patients and nodules.</p
Distribution of the probability of malignancy according to the four risk prediction models.
<p>Distribution of the probability of malignancy according to the four risk prediction models.</p
Decision curve analysis for the four risk prediction models.
<p>Decision curve analysis for the four risk prediction models.</p
Receiver operator characteristic curves for the four risk prediction models.
<p>Receiver operator characteristic curves for the four risk prediction models.</p
Histopathological results of pulmonary nodules.
<p>Histopathological results of pulmonary nodules.</p