Face and Object Recognition and Detection Using Colour Vector Quantisation

In this paper we present an approach to face and object detection and recognition based on an extension of the contentbased image retrieval method of Lu and Teng (1999). The method applies vector quantisation (VQ) compression to the image stream and uses Mahalonobis weighted Euclidean distance between VQ histograms as the measure of image similarity. This distance measure retains both colour and spatial feature information but has the useful property of being relatively insensitive to changes in scale and rotation. The method is applied to real images for face recognition and face detection applications. Tracking and object detection can be coded relatively efficiently due to the data reduction afforded by VQ compression of the data stream. Additional computational efficiency is obtained through a variation of the tree structured fast VQ algorithm also presented here

Homogenised Virtual Support Vector Machines

In many domains, reliable a priori knowledge exists that may be used to improve classifier performance. For example in handwritten digit recognition, such a priori knowledge may include classification invariance with respect to image translations and rotations. In this paper, we present a new generalisation of the Support Vector Machine (SVM) that aims to better incorporate this knowledge. The method is an extension of the Virtual SVM, and penalises an approximation of the variance of the decision function across each grouped set of "virtual examples", thus utilising the fact that these groups should ideally be assigned similar class membership probabilities. The method is shown to be an efficient approximation of the invariant SVM of Chapelle and Scholkopf, with the advantage that it can be solved by trivial modification to standard SVM optimization packages and negligible increase in computational complexity when compared with the Virtual SVM. The efficacy of the method is demonstrated on a simple problem

Implicit surfaces with globally regularised and compactly supported basis functions

We consider the problem of constructing a function whose zero set is to represent a surface, given sample points with surface normal vectors. The contributions include a novel means of regularising multi-scale compactly supported basis functions that leads to the desirable properties previously only associated with fully supported bases, and show equivalence to a Gaussian process with modified covariance function. We also provide a regularisation framework for simpler and more direct treatment of surface normals, along with a corresponding generalisation of the representer theorem. We demonstrate the techniques on 3D problems of up to 14 million data points, as well as 4D time series data

Schlafstörungen bei kritisch kranken Patienten

Zusammenfassung: Schlaf ist ein essenzieller Bestandteil des Lebens. Für eine intakte Immunabwehr, für kognitive und muskuläre Funktionen scheint Schlaf wichtig zu sein. Subjektive Schlafstörungen wurden in 20% der arbeitenden Population gefunden und nehmen mit dem Alter zu. Schlafstörungen konnten bei mehr als 50% der Patienten in kritischem Zustand nachgewiesen werden. Bei kritisch kranken Patienten ist der Schlaf bisher nur unzureichend wissenschaftlich untersucht worden. Zur Schlafmessung stehen Fragebogen und als einziges objektivierendes Verfahren die Polysomnographie zur Verfügung. Schlafstörungen in der Intensivstation haben meist multifaktorielle Ursachen: patientenbedingte Pathologien, wie Status nach größerer Chirurgie, Sepsis, akuter oder chronischer Lungenschaden, Herzinsuffizienz, Schlaganfall oder Epilepsie; therapeutische Interventionen, wie z.B. die mechanische Ventilation, Lärm verursachende technische Geräte, Schmerzen und Medikamente. Neben pharmakologischen Behandlungskonzepten mit Analgetika und zeitlich limitierten Sedativa sollten umwelthygienische Maßnahmen mit Musik zur Entspannung, nächtliche Lärmreduktion und Tageszeitpräsentation ergriffen werden. Bevor evidenzbasierte "guidelines" erstellt werden können, muss eine intensivierte Forschung im Bereich Schlaf und kritische Krankheit durchgeführt werden. Mit großen Kohortenstudien sollte untersucht werden: 1. Welche Anteile der Schlafstörungen kritisch kranker Patienten Folge von Krankheiten oder Trauma und damit nichtbeeinflussbar sind, 2. ob der Schweregrad der Schlafstörungen Ausdruck von der Schwere der Krankheit oder des Traumas ist, 3. welcher Anteil Folge medizinischer Interventionen und damit beeinflussbar ist. Mithilfe der nach Pathologie stratifizierten und randomisierten Studien sollten nichtpharmakologische und pharmakologische Konzepte zur Schlafverbesserung getestet werden. Dabei sollten sowohl nosokomiale Infektionen als auch kognitive Funktionen und respiratorische Muskelkraft berücksichtigt werden. Dann kann beurteilt werden, ob es sinnvoll ist, Schlafstörungen engmaschig zu überwachen, um sie als Verlaufsmaß des Therapieerfolgs und der kurzfristigen Lebensqualität zu nutzen. Wichtig ist, dass solche Studien einen genügend langen Follow-up-Zeitraum haben, um allfällige Entzugserscheinungen pharmakologischer Interventionen zu erfasse

A critique of the evidence for active host defence against cancer, based on personal studies of 27 murine tumours of spontaneous origin.

Extensive experience with isotransplants of 27 different tumours (leukaemias, sarcomata, carcinomata), all of strictly spontaneous origin in laboratory bred mice of low cancer strains CBA/Ht and WHT/Ht, has revealed no evidence of tumour immunogenicity. Of approximately 20,000 maintenance transplants, none failed and none regressed; of almost 10,000 carefully observed tumours arising from small or minimal inocula of tumour cells, none spontaneously regressed. The number of injected viable tumour cells required to give a 50% probability of successful transplantation (the TD50) ranged from approximately 1 cell to greater than 10,000 cells among the 27 tumours; high TD50 values, which were dramatically reduced by various procedures having no immunological significance, did not signify active "resistance" of the hosts. In the case of all of 7 randomly selected tumours, prior "immunization" of recipients with homologous lethally irradiated cells increased their tumour receptivity. Several experiments using various tumours failed to give evidence that immunity could be non-specifically induced or that a massive preponderance of lymphocytes from specifically sensitized mice could inhibit tumour transplantation or growth in vivo; no trace of "resistance" to tumour was adopted by isogeneic recipients of lymphocytes from regional nodes of tumour bearers. A limited review of the recent literature on tumour immunity shows that practically all the animal data presented in support of a general theory of tumour immunogenicity or to provide a basis for active clinical immunotherapy have been obtained from transplanted tumour systems which entail artefactual immunity associated with viral or chemical induction of the tumours or their allogeneic transplantation. It is suggested that isotransplants of spontaneously arising tumours are the only appropriate models of human cancer and that any genuine rapport between the animal laboratory and the clinic requires their exclusive use

Systemische Sklerose: Zielkriterien der Behandlung

Zusammenfassung: Die systemische Sklerose (SSc) ist eine Multisystemfibrose mit weltweitem Vorkommen und hoher Morbidität und Mortalität. Charakteristika der Erkrankung sind ausgedehnte Vaskulopathie, Entzündung, Autoimmunität und Fibrose. Therapieerfolge der letzten Jahre beinhalten im Wesentlichen ein besseres Management von Organkomplikationen. Bis heute gibt es jedoch keine zugelassene spezifische Therapie, die das Fortschreiten der Erkrankung verhindern oder auch nur verlangsamen kann. Konventionelle DMARDs ("disease-modifying antirheumatic drugs") haben keinen substanziellen Einfluss auf den Erkrankungsverlauf und verlängern das Gesamtüberleben nicht. Aufgrund molekularbiologischer Studien und verschiedener Tiermodelle konnten in den letzten Jahren Schlüsselmoleküle der Pathogenese von Fibrose und Vaskulopathie in SSc identifiziert werden. Vor diesem Hintergrund müssen nun Zielkriterien der Behandlung neu überdacht und definiert werden. In diesem Artikel werden mit Bezug auf pulmonal-arterielle Hypertonie, Lungenfibrose und Haut-/Systemfibrose aktuelle und künftige Therapiekonzepte, Ziele der Behandlung und Erfassung/Bewertung von Verlaufsparametern diskutier

Combined macro- and micro-rheometer for use with Langmuir monolayers

A Langmuir monolayer trough that is equipped for simultaneous microrheology and standard rheology measurements has been constructed. The central elements are the trough itself with a full range of optical tools accessing the air-water interface from below the trough and a portable knife-edge torsion pendulum that can access the interface from above. The ability to simultaneously measure the mechanical response of Langmuir monolayers on very different lengths scales is an important step in for our understanding of the mechanical response of such systems

A Holistic Scenario of Turbulent Molecular Cloud Evolution and Control of the Star Formation Efficiency. First Tests

We compile a holistic scenario for molecular cloud (MC) evolution and control of the star formation efficiency (SFE), and present a first set of numerical tests of it. A {\it lossy} compressible cascade can generate density fluctuations and further turbulence at small scales from large-scale motions, implying that the turbulence in MCs may originate from the compressions that form them. Below a {\it sonic} scale \ls, turbulence cannot induce any further subfragmentation, nor be a dominant support agent against gravity. Since progressively smaller density peaks contain progressively smaller fractions of the mass, we expect the SFE to decrease with decreasing \ls, at least when the cloud is globally supported by turbulence. Our numerical experiments confirm this prediction. We also find that the collapsed mass fraction in the simulations always saturates below 100% efficiency. This may be due to the decreased mean density of the leftover interclump medium, which in real clouds (not confined to a box) should then be more easily dispersed, marking the ``death'' of the cloud. We identify two different functional dependences (``modes'') of the SFE on \ls, which roughly correspond to globally supported and unsupported cases. Globally supported runs with most of the turbulent energy at the largest scales have similar SFEs to those of unsupported runs, providing numerical evidence of the dual role of turbulence, whereby large-scale turbulent modes induce collapse at smaller scales. We tentatively suggest that these modes may correspond to the clustered and isolated modes of star formation, although here they are seen to form part of a continuum rather than being separate modes. Finally, we compare with previous proposals that the relevant parameter is the energy injection scale.Comment: 6 pages, 3 figures. Uses emulateapj. Accepted in ApJ Letter

Bilateral Pneumothoraces Following Central Venous Cannulation

We report the occurrence of a bilateral pneumothoraces after unilateral central venous catheterization of the right subclavian vein in a 70-year-old patient. The patient had no history of pulmonary or pleural disease and no history of cardiothoracic surgery. Two days earlier, she had a median laparotomy under general and epidural anaesthesia. Prior to the procedure, the patient was hemodynamically stable and her transcutaneous oxygen saturation was 97% in room air. We punctured the right pleural space before cannulation of the right subclavian vein. After the procedure, the patient slowly became hemodynamically instable with respiratory distress. A chest radiograph revealed a complete left-side pneumothorax and a mild right-side pneumothorax. The right-side pneumothorax became under tension after left chest tube insertion. The symptoms finally resolved after insertion of a right chest tube. After a diagnostic work-up, we suspect a congenital “Buffalo chests” explaining bilateral pneumothoraces and a secondary tension pneumothorax