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We present a novel anti-counterfeiting and product security technique using a secure optical tag based on randomly distributed reflective micro particles. This technique can complement the existing security and logistics mechanisms like 1D/2D barcodes, DataMatrix, holograms etc. or can be used as a standalone solution too. The concept revolves around the use of random distribution of reflective microstructures as physically unclonable function (PUF). The particles are embedded into product surface or in the document. These particles are invisible to naked eye, the verification is done by imaging the reflections from these micro structures with a camera enabled cellphone equipped with some add-on optics. Here we present an overview of the system for using the secure optical tag, its registration and authentication.

Cardiovascular diseases are the leading cause of death and disability throughout the world and standard treatment in hospitals or rehabilitation centers remains one of the biggest cost-factors in healthcare. Therefore, the prevention and the secondary-prevention of cardiovascular illnesses are of paramount importance for the entire healthcare system. One possible method of prevention is the continuous telemonitoring of cardiovascular patients. Hence, the authors introduce a research project with the aim of developing a context-aware cardiovascular long-term monitoring system. The system should enable continuous patient-friendly measurements of blood-pressure and electrocardiogram (ECG). Furthermore, the system should allow an objective evaluation of the patient’s physiological parameters taking into consideration context information, such as individual activities and stress conditions. This paper places emphasis on the extraction of context-information, whereas for the evaluation of ECG and blood-pressure, the most significant factor is the physical activity. The patient’s activity or movement can be acquired from the three dimensional acceleration of the body caused by each movement. Thus, an inertial micro-sensor system with a triaxial accelerometer is presented. From the acceleration signals, different methods of movement detection and classification such as Nearest Neighbor rule, K-Nearest Neighbor rule and Neuro-fuzzy classification are investigated. Using the adaptive neuro-fuzzy inference method, an online activity recognition system has been implemented and its accuracy is shown.

Fifty-four patients with angiographically confirmed peripheral vascular disease (PVD) were examined in order to find out whether the occlusive form of this disease can be better diagnosed by measuring the reappearance time and mean velocity of the blood flow during reactive hyperemia than by determining the peripheral systolic blood pressure, using Doppler ultrasound for both measurements. It was shown that the Doppler pressure was only reliable for a screening diagnosis of PVD. However, using the reappearance time of reactive hyperemia, it was possible to distinguish specific localization types of sclerosis; while reactive hyperemia already reached its half maximum in controls in 4.6 s this occurred in the stenosis type of PVD after 6.9 s, in the upper leg occlusion type after 21.6 s, in the lower leg occlusion type after 46.6 s, and in the multilevel disease after 70.1 s. The delay in the half-maximum reappearance time was significantly different, not only in comparison with controls (P

Thalamic-striatal damage of symmetric bilateral distribution was found in four severely asphyxiated neonates born at term. Two patients showed evidence of bilateral thalamic-striatal necrosis and two showed hemorrhage of the same distribution. The four patients had a common history of prolonged asphyxia in the neonatal period combined with severe acidosis and respiratory insufficiency. The outcome was lethal in all children. Three patients survived for some time and showed additional evidence of generalized brain damage including cortical necrosis and subcortical leucomalacia and one patient was found to have intravital calcification of the putamen at 14 days of age. The appearance of thalamic-striatal damage in US, CCT and NMR imaging is discussed. Thalamic-striatal damage may not be detectable by US until several days after the initial insult. US does not permit a distinction between necrosis and hemorrhage, but CCT and NMR imaging may be successful. Only five infants with a comparable pattern of brain damage due to asphyxia have been described so far. Our own studies seem to indicate that thalamic-striatal damage is the hallmark of more widespread brain damage, and that it will be found more frequently if carefully looked for in asphyxiated neonates born at term.

Space-occupying lesions of the spinal cord and lower medulla oblongata still represent a clinical and diagnostic challenge to the neurosurgeon, and up until very recently a preoperative diagnosis of the tumor’s nature was impossible. This was because the conventional diagnostic neuro-radiological procedures such as myelography and computed tomography (CT) often fail to establish a diagnosis in the “problem” zones of the neu-raxis. These are areas with very close anatomical relations to surrounding bony structures, e.g., the temporobasal structures, the posterior fossa, and in particular the spinal cord. It is in these areas that the technique of magnetic resonance tomography (MRT) has revolutionized the neuroradiological workup and has been particularly helpful in diagnosing syringes and spinal cord tumors of various nature.

Significant progress in diagnosis of intracranial tumors has been made during the past decade. In the late 1970s, computed tomography (CT) became an established technique in neuroimaging, which had proven its diagnostic potential especially in regard to intracranial tumors [5]. In the early 1980s, magnetic resonance (MR) imaging was introduced into clinical practice [1]. Although MR is widely used nowadays and advances have been tremendous, a lot of difficulties still remain in interpreting MR data [1]. The correlation between histological diagnoses and tissue dignity on the one hand and ϱ, T1, and T2 parameters on the other hand is one area in which knowledge is limited [3, 4]: first results seem to be less promising than was hoped for at the beginning of the MR period [3, 4]. For these reasons, we reviewed some of our meningioma cases that were studied with MR and compared the very variable histological pattern of these tumors with their heterogeneous MR characteristics.

Soon after the introduction of computed tomography (CT), numerous reports documented its usefulness in detection of cerebral abnormalities in epileptic disease (e.g., 2, 3, 8, 10, 14). The total number of abnormal findings varies considerably (7, 17, 22). Magnetic resonance (MR) imaging is superior to CT in detecting cerebral demyelination, rivals CT in imaging of brain tumors, and has tremendous potential in evaluating structural disease of the central nervous system (5, 11, 21). Therefore, we investigated the value of MR in the examination of epileptic disease when CT has been normal.

During the past three years 27 patients with medullary and/or brainstem cavities were examined with MRI at the Institute of Roentgenology, and we report the radiological MRI correlative findings. Five patients were operated: postoperative MRI examinations were compared with preoperative studies.

The first images using magnetic resonance (MR) were realized in 1973 (12). Clinically useful MR scans of the head were published at the beginning of the current decade (9, 11, 16), and imaging quality has now attained high standards (3). At present the expensive MR technique is not only used in a research and university setting, but in private clinical practice too (2).

Two cases of colloid cyst of the third ventricle are reported. Their computed tomographic (CT), magnetic resonance (MR) and neuropathological features are presented. The MR findings were different in the two cases for reasons not yet fully explained, full biochemical and biophysical analyses of the cyst contents not being available. Neuropathologically, the only significant difference was the abundant presence of cholesterin crystals in the colloid of case 1 and their absence in case 2. One of our cases is also peculiar from a CT point of view, since it was primarily hypodense and did not enhance on intravenous contrast administration.