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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.

Versuche, durch Transfer eines Kerns aus einer somatischen Zelle eines Patienten in eine entkernte Ovum-Zelle Stammzell-Kulturen zu erhalten, zielen auf Therapien mit Hilfe von Patienten identischem Gewebe-Ersatz (regenerative Therapie). Die erhofften Vorteile dieser Therapie sind gros, und entsprechend intensiv ist die Suche nach ihrer Verwirklichung. Der limitierende Faktor bei derartigen Versuchen ist die geringe Zahl an verfugbaren Ova-Zellen. Die Situation eines knappen und sehr nachgefragten Gutes ist zur Kommerzialisierung dieses Gutes, in diesem Falle eines Teiles des menschlichen Korpers, geeignet. Dieser Beitrag untersucht das Spende-Verhalten in dieser Situation.

Foldable intraocular lenses (IOLs) are established in ophthalmic surgery and increasingly more complex geometries are available. This study investigates different designs of the optics of the IOL as well as the imaging quality of these optics utilizing electron microscopic photographs and mathematical approximations.Included in this study were two different lens powers of common IOLs (+ 13 D and + 26 D). All studied IOLs were processed depending upon their water content: Aqueous IOLs with up to 25 % water content were fixed with 2.5 % glutaraldehyde in 0.1 M phosphate buffer (mPP), and then contrasted with 2 % OsO (4) and processed in an alcohol series of 30 - 100 % propanol. Subsequently, the IOLs were transferred into EPON (epoxy resin) and polymerization took place at 60 degrees C. After hardening, the samples were cut out with a leaves saw and divided into halves. Afterwards these were polished with glass and diamond knifes at the ultramicrotom (Ultracut, Rückert-Jung). After coal vaporization measurement took place in the scanning electron microscope (DSM 962, Zeiss). In the case of dry stored IOLs, the samples were sputtered with Au-Pd 20 nm and afterwards measurement was performed as described above. The measurement of the optical imaging quality was performed with correctly and inversely oriented IOLs according to the standard EN ISO 11979 -- 2 by means of a measuring system which works on the basis of the point spread function (PSF) and/or the modulation transfer function (MTF). From this the Strehl ratio was computed in each case.Utilizing a correlation of the electron microscopic investigation of the optics of different IOLs with their imaging quality (Strehl ratio), we were able to show that the optical design of the IOL has substantial influence on the imaging quality of an intraocular lens. In particular, with non-symmetrical designs of the optics (e. g., AR40 e; AMO) the orientation of an IOL in the eye is crucial; i. e., the Strehl ratio increased thereby from 0.68 to 0.87.The design of asymmetrical optics is crucial and much attention should be paid to the fact that the imaging quality can substantially be affected. A correct orientation of the lens within the eye is very important with these asymmetrical optics.

Contrast imaging of new multifocal intraocular lens (MIOL) designs with 5 and 7 refractive zones was examined by in vitro measurement of the modulation transfer function (MTF) and by testing contrast sensitivity with Regan 96% and 11% contrast sensitivity charts after "optical implantation" of MIOLs in 20 healthy subjects by means of a new optical device developed by Reiner. The results were compared with those obtained with a monofocal IOL and a diffractive MIOL. We found that the MTF of both refractive MIOLs showed a reduction in contrast at corresponding spatial frequencies compared with the monofocal and with the diffractive IOL, resulting in a Strehl ratio of below 30%. Contrast sensitivity after "optical implantation" was significantly reduced for the refractive 5- and 7-zone models in high contrast (Regan 96%), but for all MIOL models in low contrast (Regan 11%) compared with the monofocal IOL. The refractive 5-zone MIOL and diffractive MIOL showed no statistical difference in contrast sensitivity.

The effective refractive index of a high frequency grating can be altered by changing its duty cycle. First experiments for infrared optical distributed index components are presented.

Optical interconnects enable the transmission of signals with ultra high frequencies with small crosstalk and rather low waste energy per transmission line. Two fields of application for optical wiring concepts can be discerned, i.e. fixed pattern chip to chip (or board to board) interconnects and reconfigurable switching networks or bus systems where the interconnect path is selected out of a number of fixed interconnects by means of e.g. so-called exchange bypass modules (EBM)1,2.

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

The infrared and Raman spectra of potassium dithioformate- d 0 and - d 1 have been interpreted and vibration frequencies assigned on the basis of a normal coordinate analysis. The force constant of the S bond is in the range 4.3–4.6 mdyn/A.

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.

For a family {T + Nλ: λ ϵ [a, b]} of semilinear operators T + Nλ in L2(Ω) the solution set {(λ, uλ) ϵ J × D(T): Tuλ + Nλuλ = h} is investigated with respect to turning points. By Ljapunov-Schmidt-reduction and calculation of the derivatives of the bifurcation equation a class of turning points is characterized by properties of these derivatives.

The i.r. and Raman spectra of the monothio-, 1,1-dithio-, 1,2-dithio- and trithio-oxalate ion in the solid state and in solution are reported. The fundamentals are assigned on the basis of normal coordinate analyses and of Raman polarisation data. Force constants for identical internal coordinates can be transferred without change within this series. In all ions the carboxylic groups are in a staggered conformation. A possible exception is the monothio-oxalate ion in the barium and lead salt.

Die IR- und RAMAN-Spektren von Metalldithiobenzoaten (M = KI, TlI, PbII, CdII, HgII und InIII) wurden registriert und mit Hilfe von Modellberechnungen zugeordnet. Die A1-Schwingungen der Dithiocarboxylatgruppe (νCCS2, νs CS2 und δ CS2) sind mit gleichrassigen Schwingungen des Phenylrings stark gekoppelt. νas CS2 liegt bei 980–1020 cm−1. Vibrational Spectra of Metal Dithiobenzoates The IR- and RAMAN spectra of metal dithiobenzoates (M = KI, TlI, PbII CdII, HgII, and InIII) have been registered and assigned on the basis of frequency calculations. The A1 modes of the dithiocarboxylic group are strongly mixed with vibrations of the phenyl ring. vas CS2 is found at 980–1020 cm−1.

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.

Die nukleare magnetische Resonanz (NMR), von S. Bloch und E.M. Purcell 1946 erstmals angewandt und inzwischen in Physik und Chemie in Form der Spektroskopie als Mes- und Analysemethode genutzt, gewinnt neuerdings im Rahmen der bildgebenden Verfahren als magnetische Resonanz-Tomographie MRT (Synonyma: MRI, Kemspintomographie) zunehmende Bedeutung in der Medizin und eroffnet speziell in der Diagnostik des Spinalkanals und des Ruckenmarkes bisher unbekannte Moglichkeiten.

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. Syringomyelia was present in 21 cases, syringobulbia in 2, and syringobulbomyelia in 4. Additional pathology such as the Arnold Chiari malformation or hydrocephalus was found at the craniospinal junction in 8 patients. Two instances of associated intraspinal tumours were noted too. In all cases the syringomyelic cavities involved the cervical cord and in most of them the lesion extended down to the thoracic or even lumbar level. Several patients were shown to have multilocular cavities. In the patients with syringomyelia a syringoarachnoidal shunting procedure was performed. This resulted in cyst collapse as proved by postoperative MRI examinations; neurological symptomatology was ameliorated too. Conventional radiological imaging with computed tomography (CT) and myelography was not as efficient as MRI in imaging syringomyelia. The extent of intramedullary cavities as well as the presence of associated pathology is best appreciated on sagittal MRI. The use of special surface coils clearly results in better image quality due to higher resolution. According to our experience MRI should be the primary examination in syringomyelia; myelography and CT are obsolete in the management of syringomyelia; the insertion of a syringoarachnoidal shunt is a convenient surgical procedure, resulting in clinical amelioration in most cases.

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.

A total of 52 patients with prostatic carcinoma were examined by MR imaging; 14 of them subsequently underwent radical prostatectomy and were included in this study. The resected prostates were sectioned axially and compared with the corresponding MR scans with special reference to the location and extent of the pathological changes. The prostatic carcinoma was visualized in 10 cases, but the size of the tumor was underestimated in 6 patients. In 9 of 10 patients the carcinoma was identifiable as an area of low signal intensity within the peripheral zone on T2-weighted images. The MR features of benign nodular hyperplasia are discussed.

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.

The "perfect shuffle" (PS) is a well-known concept for global interconnection networks in parallel computers. It performs a certain permutation of N = 2k elements. Fig. 1 shows two different graphical representations of the PS-operation. In Fig. 1a the actual pathways of the N elements in one PS-step are drawn. If the addresses (positions) of the elements are represented by binary numbers, ranging from 0 to N-1, it is apparent that the PS can be described as a cyclical rotation (to the left) of the address bits (Fig. 1b).

The frequency of bilateral primary (simultaneous and nonsimultaneous) breast cancer in 1420 patients was reported. The number of cases of bilateral breast cancer not caused by metastases amounted to 1,75%. The problems and significance of follow-up checks was discussed.

THE recorded annual incidence of tornadoes in the United States has increased steadily and dramatically in the past four decades, by at least a factor of six1. We have examined the thesis that the development of widespread motor vehicle traffic in the United States over the last 40 yr has perturbed atmospheric vorticity in such a way as to exacerbate the tornado incidence, principally by the introduction of cyclonic vorticity. Surprisingly, both the analysis and the evidence support the thesis.