398 research outputs found
Identification and Detection of Gaseous Effluents from Hyperspectral Imagery Using Invariant Algorithms
The ability to detect and identify effluent gases is, and will continue to be, of great importance. This would not only aid in the regulation of pollutants but also in treaty enforcement and monitoring the production of weapons. Considering these applications, finding a way to remotely investigate a gaseous emission is highly desirable. This research utilizes hyperspectral imagery in the infrared region of the electromagnetic spectrum to evaluate an invariant method of detecting and identifying gases within a scene. The image is evaluated on a pixel-by-pixel basis and is studied at the subpixel level. A library of target gas spectra is generated using a simple slab radiance model. This results in a more robust description of gas spectra which are representative of real-world observations. This library is the subspace utilized by the detection and identification algorithms. The subspace will be evaluated for the set of basis vectors that best span the subspace. The Lee algorithm will be used to determine the set of basis vectors, which implements the Maximum Distance Method (MaxD). A Generalized Likelihood Ratio Test (GLRT) determines whether or not the pixel contains the target. The target can be either a single species or a combination of gases. Synthetically generated scenes will be used for this research. This work evaluates whether the Lee invariant algorithm will be effective in the gas detection and identification problem
DIAGNOSTIC ACCURACY OF IXIP INDEX AND PROSTATE MRI IN THE DIAGNOSIS OF PROSTATE CANCER: PRELIMINARY RESULTS ON A COMBINED APPROACH
The purpose of this study was to assess whether Immune CompleX Predictive Index (iXip) improves diagnostic accuracy of multiparametric prostate MRI (mpMRI) for clinically significant prostate cancer. This study included 72 patients (mean age: 68±8 years) with suspicion of prostate cancer and available iXip score. mpMRI images were evaluated by two radiologists according to the PI-RADS v2.1. Reference standard was based on fusion biopsy and standard transperineal 12-point biopsy. Diagnostic accuracy of iXip, mpMRI and their combination were calculated. Optimal cutoff of iXip with sensitivity and specificity was identified using the Youden index. Patients with clinically significant prostate cancers had significantly higher iXip values compared to patients without clinically significant prostate cancers (median 0.411 vs 0.273; p=0.026). The AUROC for iXip was 0.795 (95% CI 0.579-1.000, p=0.026). Sensitivity and specificity were 75% and 100% respectively for mpMRI alone, and 100% and 80% respectively for mpMRI combined with iXip > 0.375. The combination of mpMRI with a cutoff value of iXip > 0.375 has a very high sensitivity for the diagnosis of prostate cancer and a moderately high specificity
Toxoplasma gondii in raw milk from Sicily
Toxoplasma gondii tachyzoites shed in milk of infected animals are a potential source of human infection often underestimated. Furthermore, limited risk assessment studies have been carried out to evaluate the transmission of toxoplasmosis by milk consumption. In this frame the availability of few and often not validated analytical methods can be a major shortcoming when investigating the extent of milk contamination and the parasite viability. To address the issue, 1381 samples of raw milk from unknown sero-status cows, donkeys, sheep and goats were examined for the detection of T. gondii DNA by a real time PCR method targeting the 529bp repeating element. The protozoan DNA was detected in 67 samples of cow’s milk (4,93% and 35% individual and herd prevalence respectively) and in one sample of donkey milk. Allegedly, on farm cats cohabitation as well as extensive management in the cattle farms that tested positive, can be accounted for environmental loading and transmission of T. gondii oocysts that are the unique sources of infection for milk-producing animals. Food safety-wise, results are noteworthy since recently raw cow’s milk consumption has become increasingly popular with the spread of automatic raw milk vending machines. Albeit heating treatment before consumption is mandatory for consumers, neglect of this requirement cannot be ruled out and could lead the way for foodborne infection. This is particularly true in view of evidences that T. gondii tachyzoites in experimentally spiked cow’s milk samples could be able to survive in gastric fluids for long enough (1 h) before reaching the intestine and infect the host
Evaluation of posttreatment response of hepatocellular carcinoma: comparison of ultrasonography with second-generation ultrasound contrast agent and multidetector CT
We evaluated the ability of one-month follow-up contrast-
enhanced ultrasound (CEUS) with second-generation
contrast agent in monitoring radio frequency
ablation (RFA) and transcatheter arterial chemoembolization
(TACE) treatments of hepatocellular carcinoma
(HCC). One-hundred forty-eight HCCs were studied
using CEUS: 110 nodules were treated with RFA [41/110
RFA were performed using a pretreatment and an
immediate postablation evaluation using CEUS (group
1); 69/110 using only US guidance (group 2)] and 38
nodules treated with TACE. For statistical analysis,
McNemar test was used. Overall complete response was
observed in 107/148 nodules (92/110 treated with RFA
and 15/38 with TACE). A better rate of complete response
was found in group 1 compared to group 2
(92.7% vs. 78.3%). In RFA treatment, CEUS showed a
sensitivity of 83.3% and a specificity of 100% (diagnostic
accuracy of 97%) using MDCT as reference standard
with no statistical difference (p > 0.05). CEUS detected
all cases of incomplete response in HCC treated with
TACE using angiography as reference standard (diagnostic
accuracy 100%).We recommend assessing residual
intratumoral flow on CEUS during RFA procedure to
determine the necessity of immediate additional treatment.
In case of positive CEUS results, HCC treated
with TACE should be considered still viable
Radiomics and prostate MRI: Current role and future applications
Multiparametric prostate magnetic resonance imaging (mpMRI) is widely used as a triage test for men at a risk of prostate cancer. However, the traditional role of mpMRI was confined to prostate cancer staging. Radiomics is the quantitative extraction and analysis of minable data from medical images; it is emerging as a promising tool to detect and categorize prostate lesions. In this paper we review the role of radiomics applied to prostate mpMRI in detection and localization of prostate cancer, prediction of Gleason score and PI-RADS classification, prediction of extracapsular extension and of biochemical recurrence. We also provide a future perspective of artificial intelligence (machine learning and deep learning) applied to the field of prostate cancer
Imaging appearance of treated hepatocellular carcinoma.
Surgical resection and imaging guided treatments play a crucial role in the management of hepatocellular carcinoma (HCC). Although the primary end point of treatment of HCC is survival, radiological response could be a surrogate end point of survival, and has a key role in HCC decision-making process. However, radiological assessment of HCC treatment efficacy is often controversial. There are few doubts on the evaluation of surgical resection; in fact, all known tumor sites should be removed. However, an unenhancing partial linear peripheral halo, in most cases, surrounding a fluid collection reducing in size during follow-up is demonstrated in successfully resected tumor with bipolar radiofrequency electrosurgical device. Efficacy assessment of locoregional therapies is more controversial and differs between percutaneous ablation (e.g., radiofrequency ablation and percutaneous ethanol injection) and transarterial treatments (e.g., conventional transarterial chemoembolization, transarterial chemoembolization with drug eluting beads and radioembolization). Finally, a different approach should be used for new systemic agent that, though not reducing tumor mass, could have a benefit on survival by delaying tumor progression and death. The purpose of this brief article is to review HCC imaging appearance after treatment
The synthesis of quinolone natural products from pseudonocardia sp.
Abstract The synthesis of four quinolone natural products from the actinomycete Pseudonocardia sp. is reported. The key step involved a sp2–sp3 Suzuki–Miyaura reaction between a common boronic ester lateral chain and various functionalised quinolone cores. The quinolones slowed growth of E. coli and S. aureus by inducing extended lag phases.The research leading to these results has received funding from the European Reserach Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) ERC grant agreement no [279337/DOS]. Research in the DRS lab is also supported by the Engineering and Physical Sciences Research Council, Biotechnology and BiologicalSciences Research Council, Medical Research Council, Cancer Research UK, and the Wellcome Trust. Work in the MW lab is supported by the BBSRC and MRC. JTH was supported by Trinity College Cambridge. Data accessibility: all data supporting this study are provided as Supplementary Information accompanying this paper.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/ejoc.20150140
Collaborative asteroid photometry for 3653 Klimishin, 4748 Tokiwagozen and 9951 Tyrannoasurus
Photometric observations of three main-belt asteroids were made in order to acquire lightcurves. The synodic
period and light curve amplitude were found for: 3653 Klimishin 6.783 ± 0.001 h, 0.21 mag; 4748 Tokiwagozen 39.78 ± 0.01 h, 0.42 mag.; 9951 Tyrannosaurus 3.767 ± 0.004 h, 0.21 mag. Asteroid 4748’s lightcurve shows a few interesting features which suggest the opportunity of further observations in order to verify a possible ”tumbling” nature.peer-reviewe
CT imaging findings of abdominopelvic vascular compression syndromes: what the radiologist needs to know
Abdominopelvic vascular compression syndromes include a variety of uncommon conditions characterized by either extrinsic compression of blood vessels by adjacent anatomical structures (i.e., median arcuate ligament syndrome, nutcracker syndrome, May-Thurner syndrome) or compression of hollow viscera by adjacent vessels (i.e., superior mesenteric artery syndrome, ureteropelvic junction obstruction, ureteral vascular compression syndromes, portal biliopathy). These syndromes can be unexpectedly diagnosed even in asymptomatic patients and the predisposing anatomic conditions can be incidentally discovered on imaging examinations performed for other indications, or they can manifest with atypical abdominal symptoms and acute complications, which may lead to significant morbidity if unrecognized. Although computed tomography (CT) is an accurate noninvasive technique for their detection, the diagnosis remains challenging due to the uncommon clinical presentation and often overlooked imaging features. Dynamic imaging may be performed in order to evaluate patients with inconstant symptoms manifesting in a specific position. The purposes of this paper are to review the CT imaging findings of abdominopelvic vascular compression syndromes, correlating with anatomical variants and to provide key features for the noninvasive imaging diagnosis
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