In this study, two experiments are reported which investigated the relative importance of five different image based factors and one human factor (training) in mediating threat detection performance of human operators in airport security x-ray screening. Experiment 1 was based on a random sample of roughly 16’000 records of threat image projection (TIP) data. TIP is a software function availabl...

We present evidence of X-ray rotational modulation on VXR45, a young fast rotator star, member of IC 2391. It is a dG9 spectral type star whose rotational period and X-ray luminosity make it a supersaturated star. Our X-ray observation, made with EPIC/PN on XMM-Newton, covers about two photometric rotational periods. The detection of˚modulation implies the presence of structural inhomogeneities...

The International Monitoring System (IMS) employs some special radiation detectors to monitor atmospheric or underground nuclear weapons tests around the world. These detectors should be able to detect ultra low concentrations of xenon radioisotopes in the atmosphere where the background level is relatively high. Exploiting the fact that the most interesting xenon radioisotopes (Xe, Xe, Xe, and...

Background: Currently, the detection of retained wood is a frequent but challenging task in emergency care. The purpose of this study is to demonstrate improved foreign-body detection with the novel approach of preclinical X-ray dark-field radiography. Methods: At a preclinical dark-field x-ray radiography, setup resolution and sensitivity for simultaneous detection of wooden and metallic parti...

A new method in differentiation of chiral molecules is reported based on the fluorescence quenching of functionalized CdS quantum dots (CdS-QDs) as nanosensor by differing in the chirality of functionalization species. The chemically functionalized CdS-QDs with strong yellow emission were prepared using chiral L-cysteine (L-Cyst) and D-cysteine (D-Cyst) molecules. Then, the functionalized CdS-Q...

Objective: The annual incidence of cancer in the world is growing rapidly. The most important factor in the cure of cancers is their early diagnosis. miRNA, as a biomarker for early detection of cancer, has attracted a lot of attention. Methods: In this study, an electrochemical biosensor was developed to detect the amount of miR-106a, the biomarker of gastric cancer, by modifying a glass...

Ray-tracing algorithms can be used to render a virtual scene and to detect collisions between objects. Numerous ray-tracing algorithms have been proposed which use data structures optimized for specific cases (rigid objects, deformable objects, etc.). Some solutions try to optimize performance by combining several algorithms to use the most efficient algorithm for each ray. This paper presents ...

The performance of 5,717 aviation security screeners in detecting prohibited items in x-ray images of passenger bags was analyzed over a period of 4 years. The measure used in this study was detection performance on the X-Ray Competency Assessment Test (X-Ray CAT) and performance on this measure was obtained on an annual basis. Between tests, screeners performed varying amounts of training in t...

We report the detection of well resolved, extended X-ray emission from the young planetary nebula BD +30 3639 using the Advanced CCD Imaging Spectrometer (ACIS) aboard the Chandra X-ray Observatory. The X-ray emission from BD +30 3639 appears to lie within, but is concentrated to one side of, the interior of the shell of ionized gas seen in high-resolution optical and IR images. The relatively ...

We present the Xand γ-ray detection of GRB 990704 and the discovery and study of its X-ray afterglow, 1SAX J1219.5-0350. Two pointed BeppoSAX observations with the narrow field instruments were performed on this source, separated in time by one week. The decay of the X-ray flux within the first observation appears unusually slow, being best-fit by a power law with negative index 0.83±0.16. Such...