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21.
Gerrit Hornung 《Datenschutz und Datensicherheit - DuD》2007,31(3):181-185
Die Bundesregierung hat die erste Stufe der Ver?nderungen des Reisepasses — die Erg?nzung um einen RFID-Chip mit biometrischen
Gesichtsdaten — ohne Ver?nderung der passrechtlichen Grundlagen vorgenommen. Für die nunmehr in der zweiten Stufe geplante
zus?tzliche Speicherung der Fingerabdrucksdaten existiert seit Anfang 2007 ein Gesetzesentwurf, der die Vorgaben der EG-Verordnung
2252/2004 übernimmt, notwendige Folgeregelungen umsetzt und weitere Ver?nderungen des Passgesetzes enth?lt. Der Beitrag skizziert
die bisherige Entwicklung, erl?utert den Inhalt des Entwurfs und der Stellungnahme des Bundesrates und nimmt eine rechtliche
Bewertung vor. 相似文献
22.
To investigate the inductive activities of the vertebrate organizer, we transplanted the chicken organizer (Hensen's node) into zebrafish gastrula and analyzed resulting secondary axes. Grafted Hensen's node did not differentiate or participate in the secondary axis. It also did not induce a secondary notochord or expression of the genes normally expressed by the fish organizer including no tail, axial, goosecoid. Nevertheless, it recruited fish cells to organize a variety of tissues: the dorsal portion of the central nervous system including Rohon-Beard sensory neurons, otic vesicles, dorsal pigment stripe, dorsal fin, somites, heart, and pronephric ducts. Enlarged neural plate induced by the organizer was shown by the expression pattern of dlx3 and msxB genes, which demarcates the early presumptive neural tissue. In addition, Hensen's node of an earlier stage chicken embryo displayed differential movement in zebrafish from that of a later stage. This might reflect unknown differences in properties between the organizer at two different developmental stages related to its normal organizer activity. To create a model system to study the molecular mechanisms of the organizer, we next transplanted genetically modified mouse cells into zebrafish embryos. We found that Wnt3A-transfected NIH3T3 cells are much more potent in inducing a secondary axis than NIH3T3 cells alone. These results suggest that formation of a variety of tissues are controlled by signalling from the organizer itself with no requirement of participation of the organizer-derived tissues. Additionally, the activities of the organizer may involve a function of Wnt-family genes. 相似文献
23.
Vinciane Lacroix 《Pattern recognition letters》1990,11(12):797-802
In this article, we consider techniques that provide edge strength at each pixel using two orthogonal directions and question their invariance with respect to a rotation. 相似文献
24.
This paper describes an analytical method to determine the visible parts of a Cartesian product surface. The bounds of these visible areas are determined in terms of the (u, v)-parameter-plane. This leads to many advantages over approximating algorithms. The new method allows the calculation and display of only the boundaries and contour curves with high precision. It calculates the critical points of a surface (contours, overlapping contours, penetrations) with machine precision, independent of the resolution of the output device and makes the parallel output on vector- and raster-devices possible. The results of this method are invarying under image-transformations. 相似文献
25.
Faster solutions to 3-D visibility problems and better distribution of multiprocessor systems can be achieved when this new connectivity data algorithm is used. 相似文献
26.
DE Hornung DB Kurtz CB Bradshaw DM Seipel PF Kent DC Blair P Emko 《Canadian Metallurgical Quarterly》1998,64(4):549-556
Acute low back pain is a common problem in the emergency department (ED). Effective management of acute pain enhances early rehabilitation and recovery. Given the importance of inflammatory mediators in pain generation and the adverse effects associated with opioids, it is logical to expect that a non-opioid agent with antiinflammatory and analgesic properties would provide excellent analgesia with fewer adverse effects. This double-blind, randomized, multicenter clinical trial, performed in six university and community hospital EDs, compares the analgesic efficacy and adverse effects of ketorolac to those of acetaminophen-codeine in ED patients with acute musculoskeletal low back pain. Our hypothesis was that ketorolac would provide superior analgesia with fewer adverse effects. One hundred twenty-three patients with acute low back pain were randomized to receive ketorolac (KET, N = 63) or acetaminophen-codeine (ACOD, N = 60). Most (79%) were males, and the mean age was 34.5 years. After baseline clinical assessment, patients were treated with ketorolac (10 mg every 4 to 6 h as needed, up to four daily doses) or acetaminophen-codeine (600 mg-60 mg, respectively, every 4 to 6 h as needed, up to six daily doses) and followed for one week. Pain intensity was assessed on visual analogue and categorical scales. Functional capacity, overall pain relief, and overall medication rating were assessed on categorical scales. Adverse events were documented. Primary outcomes included: 1) Pain intensity differences, based on visual analogue scores, for the 0 to 6 h treatment phase. 2) Incidence of adverse events. Secondary outcomes included analgesic efficacy, functional capacity, and overall subjective drug evaluation at one week. Both drugs provided substantial pain relief, with maximal effect 2.2 h after oral dosing. There were no significant differences in analgesic efficacy, functional capacity, or overall pain relief between the two groups. Sixteen patients (10 KET vs. 6 ACOD, NS) withdrew prematurely because of drug inefficacy. Patients in the ACOD group reported significantly more adverse drug events and serious adverse drug events. Seven patients--all in the ACOD group--withdrew from the study because of adverse drug events. Based on comparable efficacy and a superior adverse event profile, ketorolac was preferable to acetaminophen with codeine for the treatment of acute low back pain in the ED. 相似文献
27.
OBJECTIVE: To evaluate prospectively the recently developed method of extracorporeal shock-wave treatment of stones of the parotid gland. PATIENTS AND METHODS: 76 patients with symptomatic, sonographically proven, solitary stones of the parotid gland (36 females, 40 males; aged 2-80 years) were treated with extracorporeal piezoelectric shock-wave lithotripsy (ESWL) after failed conservative management (sialagogues, gland massage, duct bougie dilation). RESULTS: Parotid stones were no longer demonstrable after a mean follow-up time of 48 (6-71) months in 38 of the 76 patients; they were symptom-free and no new stones had formed. A residual, but symptom-free, stone was found in another 20 patients (26%) of whom 13 (17%) reported marked improvement after ESWL. No change from pretreatment symptoms occurred in five patients (7%) so that operative removal had to be performed. The success rate of the lithotripsy was independent of size and site of the stone. CONCLUSION: ESWL is the method of first choice in the treatment of parotid gland stones after unsuccessful conservative treatment and obviates operative gland removal in most cases. 相似文献
28.
R Sader HF Zeilhofer H Deppe HH Horch B Nuber B Hornung 《Canadian Metallurgical Quarterly》1995,16(6):269-274
AIM: The use of a new 3D ultrasound system should reduce the drawbacks of former 3D workstations (long image generation time, limited use due to the need for special 3D transducers), so that it is now applicable in daily clinical routine. METHOD: An ultrasound 3D workstation was used based on a pentium PC platform, employing a magnetoelectronic position detection system for spatial reconstruction of conventional 2D B-scan image sequences. RESULTS: Better assessment of topographico-anatomical spatial relationships was achieved when presenting pathological findings, especially in assessing lymph nodes and salivary stones. Pathological processes in the maxillofacial area occurring during a period of five months were visualised. CONCLUSION: The method of 3D reconstruction of standard two-dimensional electronic scans, as presented here, is the first method of its kind enabling applicability in daily clinical routine thanks to rapid imaging. The images can be produced with any ultrasound unit or transducer. First clinical results in maxillofacial surgery clearly show improved diagnostic possibilities although there still room for an improvement of the image quality. The possibility of semi-automatic exact volumetry appears meaningful especially in the investigation of lymph nodes. Integration of colour duplex sonography will further enhance the diagnostic value of this method. 相似文献
29.
Mariana Tasso Thomas Pons Nicolas Lequeux Julie Nguyen Zsolt Lenkei Diana Zala 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(47)
Single‐particle tracking with quantum dots (QDs) constitutes a powerful tool to track the nanoscopic dynamics of individual cell membrane components unveiling their membrane diffusion characteristics. Here, the nano‐resolved population dynamics of QDs is exploited to reconstruct the topography and structural changes of the cell membrane surface with high temporal and spatial resolution. For this proof‐of‐concept study, bright, small, and stable biofunctional QD nanoconstructs are utilized recognizing the endogenous neuronal cannabinoid receptor 1, a highly expressed and fast‐diffusing membrane protein, together with a commercial point‐localization microscope. Rapid QD diffusion on the axonal plasma membrane of cultured hippocampal neurons allows precise reconstruction of the membrane surface in less than 1 min with a spatial resolution of tens of nanometers. Access of the QD nanoconstructs to the synaptic cleft enables rapid 3D topological reconstruction of the entire presynaptic component. Successful reconstruction of membrane nano‐topology and deformation at the second time‐scale is also demonstrated for HEK293 cell filopodia and axons. Named “nanoPaint,” this super‐resolution imaging technique amenable to any endogenous transmembrane target represents a versatile platform to rapidly and accurately reconstruct the cell membrane nano‐topography, thereby enabling the study of the rapid dynamic phenomena involved in neuronal membrane plasticity. 相似文献
30.
Modeling of a Methanol Synthesis Reactor for Storage of Renewable Energy and Conversion of CO2 – Comparison of Two Kinetic Models
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Johannes J. Meyer Pepe Tan Andreas Apfelbacher Robert Daschner Andreas Hornung 《化学工程与技术》2016,39(2):233-245
The storage of renewable energy over a long time period, via methanol synthesis, will become very important to reach a greenhouse gas‐free energy supply. A steady‐state methanol synthesis flowsheet, containing a 2D pseudo‐homogeneous reactor, flash, and recycle, is modeled in MATLAB. With the kinetic models of Graaf and Bussche & Froment, two frequently used kinetic models for conventional methanol synthesis are compared and evaluated for applicability regarding methanol synthesis from CO2/H2. The results are presented for different cases of synthesis gas compositions. Both kinetic models produce similar results when the system is limited by thermodynamic equilibrium. However, differences in reaction rates are observable from the reactor axial molar component profiles of the reaction products. 相似文献