141 research outputs found
Finanzielle Berichterstattung von PPP unter IPSAS : Ein Projekt in Zusammenarbeit mit der Förderagentur fĂŒr Innovation des Bundes KTI
In der wissenschaftlichen und politischen Debatte fĂ€llt die ambivalente Haltung gegenĂŒber den PPP auf. Auf der einen Seite wird PPP wegen seiner Effizienz- und EffektivitĂ€tsvorteile gepriesen und auf der anderen Seite wird PPP als ein Mittel zur Umgehung der Schuldenbremsen betrachtet.
Das Ziel unserer Studie ist mit Hilfe der wirtschaftlichen Betrachtungsweise aus der Rechnungslegungstheorie ("Substance over form") eine BrĂŒcke zwischen den beiden Lagern zu schlagen: Indem man klare Regeln fĂŒr eine transparente Berichterstattung festlegt, kann man eine Instrumentalisierung von PPP fĂŒr fiskalpolitische Spielereien verhindern und rĂŒckt so die Wirtschaftlichkeitsbetrachtung von PPP in den Vordergrund.
Um dieses Ziel zu erreichen, steht die Beantwortungen der folgenden beiden Forschungsfragen im Zentrum dieser Arbeit:
⹠Wie sind PPP gemÀss einer wirtschaftlichen Betrachtungsweise in der Rechnungslegung nach IPSAS abzubilden und wie kann insbesondere der neue IPSAS zu den Dienstleistungskonzessionen in der Praxis angewendet werden?
âą Welche Auswirkungen hat die wirtschaftliche Betrachtungsweise auf die finanzielle Berichterstattung und die Schuldenbremse?
Um diese Fragen zu beantworten, wird in einem ersten Schritt der Forschungsgegenstand PPP umschrieben. Insbesondere wird auf die zwei in der Praxis und Theorie am meisten diskutierten Gesichtspunkte rund um das Konzept PPP eingegangen: Die verdeckte Verschuldung sowie Effizienz- und EffektivitĂ€tsvorteile. Diese beiden Aspekte stehen in einem unmittelbaren Zusammenhang mit den Anforderungen der modernen Rechnungslegung und so wird der Bogen zur Darstellung von PPP in der Rechnungslegung auf Basis einer wirtschaftlichen Betrachtungsweise gespannt. Nach einem Ăberblick ĂŒber die verschiedenen internationalen AnsĂ€tze wird der neue Lösungsansatz vom IPSAS-Board aufgezeigt. Die International Federation of Accountants, welche Projektpartner beim KTI-Projekt PPP unter IPSAS ist, hat unter Mitarbeit des Instituts fĂŒr Verwaltungs-Management einen Lösungsvorschlag erarbeitet, der vom IPSAS-Board im September 2009 verabschiedet wird.
Dieser neue Ansatz von IPSAS wird auf Praxisbeispiele angewendet und dadurch werden die Prinzipien dieses Ansatzes fĂŒr die Anwendung in der Praxis aufbereitet. Mit den Praxisbeispielen und der strukturierten Ăbersicht im Anhang soll ein Leitfaden fĂŒr die Anwendung dieses neuen Ansatzes in der Praxis gegeben werden. Im letzten Kapitel wird der IPSAS-Ansatz aus einer theoretischen Sicht gewĂŒrdigt und es werden die Auswirkungen auf die finanzielle Berichterstattung sowie die Schuldenbremse aufgezeigt
Robust Tumor Segmentation with Hyperspectral Imaging and Graph Neural Networks
Segmenting the boundary between tumor and healthy tissue during surgical
cancer resection poses a significant challenge. In recent years, Hyperspectral
Imaging (HSI) combined with Machine Learning (ML) has emerged as a promising
solution. However, due to the extensive information contained within the
spectral domain, most ML approaches primarily classify individual HSI
(super-)pixels, or tiles, without taking into account their spatial context. In
this paper, we propose an improved methodology that leverages the spatial
context of tiles for more robust and smoother segmentation. To address the
irregular shapes of tiles, we utilize Graph Neural Networks (GNNs) to propagate
context information across neighboring regions. The features for each tile
within the graph are extracted using a Convolutional Neural Network (CNN),
which is trained simultaneously with the subsequent GNN. Moreover, we
incorporate local image quality metrics into the loss function to enhance the
training procedure's robustness against low-quality regions in the training
images. We demonstrate the superiority of our proposed method using a clinical
ex vivo dataset consisting of 51 HSI images from 30 patients. Despite the
limited dataset, the GNN-based model significantly outperforms context-agnostic
approaches, accurately distinguishing between healthy and tumor tissues, even
in images from previously unseen patients. Furthermore, we show that our
carefully designed loss function, accounting for local image quality, results
in additional improvements. Our findings demonstrate that context-aware GNN
algorithms can robustly find tumor demarcations on HSI images, ultimately
contributing to better surgery success and patient outcome.Comment: 11 pages, 6 figure
Wavelet-Based Angiographic Reconstruction of Computed Tomography Perfusion Data Diagnostic Value in Cerebral Venous Sinus Thrombosis
Objective: The aim of this study was to test the diagnostic value of wavelet-based angiographic reconstruction of CT perfusion data (waveletCTA) to detect cerebral venous sinus thrombosis (CVST) in patients who underwent whole-brain CT perfusion imaging (WB-CTP). Materials and Methods: Datasets were retrospectively selected from an initial cohort of 2863 consecutive patients who had undergone multiparametric CT including WB-CTP. WaveletCTA was reconstructed from WB-CTP: the angiographic signal was generated by voxel-based wavelet transform of time attenuation curves (TACs) from WB-CTP raw data. In a preliminary clinical evaluation, waveletCTA was analyzed by 2 readers with respect to presence and location of CVST. Venous CT and MR angiography (venCTA/venMRA) served as reference standard. Diagnostic confidence for CVST detection and the quality of depiction for venous sections were evaluated on 5-point Likert scales. Thrombus extent was assessed by length measurements. The mean CT attenuation and waveletCTA signal of the thrombus and of flowing blood were quantified. Results: Sixteen patients were included: 10 patients with venCTA-/venMRAconfirmed CVST and 6 patients with arterial single-phase CT angiography (artCTA)-suspected but follow-up-excluded CVST. The reconstruction of waveletCTA was successful in all patients. Among the patients with confirmed CVST, waveletCTA correctly demonstrated presence, location, and extent of the thrombosis in 10/10 cases. In 6 patients with artCTA-suspected but follow-up-excluded CVST, waveletCTA correctly ruled out CVST in 5 patients. Reading waveletCTA in addition to artCTA significantly increased the diagnostic confidence concerning CVST compared with reading artCTA alone (4.4 vs 3.6, P = 0.044). The mean flowing blood-to-thrombus ratio was highest in waveletCTA, followed by venCTA and artCTA (146.2 vs 5.9 vs 2.6, each with P < 0.001). In waveletCTA, the venous sections were depicted better compared with artCTA (4.2 vs 2.6, P < 0.001), and equally well compared with venCTA/venMRA (4.2 vs 4.1, P = 0.374). Conclusions: WaveletCTA was technically feasible in CVST patients and reliably identified CVST in a preliminary clinical evaluation. WaveletCTA might serve as an additional reconstruction to rule out or incidentally detect CVST in patients who undergo WB-CTP
Crossed cerebellar diaschisis in acute ischemic stroke: Impact on morphologic and functional outcome
Crossed cerebellar diaschisis (CCD) is the phenomenon of hypoperfusion and hypometabolism of the contralateral cerebellar hemisphere caused by dysfunction of the related supratentorial region. Our aim was to analyze its influence on morphologic and functional outcome in acute ischemic stroke. Subjects with stroke caused by a large vessel occlusion of the anterior circulation were selected from an initial cohort of 1644 consecutive patients who underwent multiparametric CT including whole-brain CT perfusion. Two experienced readers evaluated the posterior fossa in terms of CCD absence (CCD-) or presence (CCD+). A total of 156 patients formed the study cohort with 102 patients (65.4%) categorized as CCD- and 54 (34.6%) as CCD+. In linear and logistic regression analyses, no significant association between CCD and final infarction volume (beta = -0.440, p = 0.972), discharge mRS2 (OR = 1.897, p = 0.320), or 90-day mRS <= 2 (OR = 0.531, p = 0.492) was detected. CCD+ patients had larger supratentorial cerebral blood flow deficits (median: 164 ml vs. 115 ml;p = 0.001) compared to CCD-patients. Regarding complications, CCD was associated with a higher rate of parenchymal hematomas (OR = 4.793, p = 0.035). In conclusion, CCD is frequently encountered in acute ischemic stroke caused by large vessel occlusion of the anterior circulation. CCD was associated with the occurrence of parenchymal hematoma in the ipsilateral cerebral infarction but did not prove to significantly influence patient outcome
Clinical and molecular characterization of a brazilian cohort of campomelic dysplasia patients, and identification of seven new SOX9 mutations
Campomelic dysplasia (CD) is an autosomal, dominantly inherited, skeletal abnormality belonging to the subgroup of bent bone dysplasias. In addition to bowed lower limbs, CD typically includes the following: disproportionate short stature, flat face, micrognathia, cleft palate, bell-shaped thorax, and club feet. Up to three quarters of 46,XY individuals may be sex-reversed. Radiological signs include scapular and pubic hypoplasia, narrow iliac wings, spaced ischia, and bowed femora and tibiae. Lethal CD is usually due to heterozygous mutations in SOX9, a major regulator of chondrocytic development. We present a detailed clinical and molecular characterization of nine Brazilian CD patients. Infants were either stillborn (n = 2) or died shortly after birth and presented similar phenotypes. Sex-reversal was observed in one of three chromosomally male patients. Sequencing of SOX9 revealed new heterozygous mutations in seven individuals. Six patients had mutations that resulted in premature transcriptional termination, while one infant had a single-nucleotide substitution at the conserved splice-site acceptor of intron 1. No clear genotype-phenotype correlations were observed. This study highlights the diversity of SOX9 mutations leading to lethal CD, and expands the group of known genetic alterations associated with this skeletal dysplasia
An IRT Analysis of Motive Questionnaires: The Unified Motive Scales
Multiple inventories claiming to assess the same explicit motive (achievement, power, or affiliation) show only mediocre convergent validity. In three studies (N = 1685) the structure, nomological net, and content coverage of multiple existing motive scales was investigated with exploratory factor analyses. The analyses revealed four
approach factors (achievement, power, affiliation, and intimacy) and a general avoidance factor with a facet structure. New scales (the Unified Motive Scales; UMS) were developed using IRT, reflecting these underlying dimensions. In comparison to existing questionnaires, the UMS have the highest measurement precision and provide short (6-item) and ultra-short (3-item) scales. In a fourth study (N = 96), the UMS demonstrated incremental validity over existing motive scales with respect to several outcome criteria
Charge-Induced Structural Changes in a Single Molecule Investigated by Atomic Force Microscopy
Intramolecular structural relaxations occurring upon electron transfer are crucial in determining the rate of redox reactions. Here, we demonstrate that subangstrom structural changes occurring upon single-electron charging can be quantified by means of atomically resolved atomic force microscopy (AFM) for the case of single copper(II)phthalocyanine (CuPc) molecules deposited on an ultrathin NaCl film. Imaging the molecule in distinct charge states (neutral and anionic) reveals characteristic differences in the AFM contrast. In comparison to density functional theory simulations these changes in contrast can be directly related to relaxations of the molecule's geometric structure upon charging. The dominant contribution arises from a nonhomogeneous vertical relaxation of the molecule, caused by a change in the electrostatic interaction with the surface
Kleinzelliges neuroendokrines Karzinom des Kopf-Hals-Bereichs: eine Ăbersichtsarbeit und Fallserie
EinleitungâKleinzellige neuroendokrine Karzinome (KNK) des Larynx sind eine seltene TumorentitĂ€t mit schlechter Prognose bei einer 5-Jahres-Ăberlebensrate nach Standardtherapie mit primĂ€rer Radiochemotherapie (pRCT) von 5â%.
MethodenâEs erfolgte eine systematische Literaturrecherche auf PubMed mit den Suchbegriffen âsmall cell neuroendocrine carcinomaâ und âhead and neckâ sowie die Aufarbeitung von PatientenfĂ€llen aus unserer Klinik.
ErgebnisseâDie Recherche ergab keine groĂen randomisierten kontrollierten Studien zur Standardtherapie. Bisherige Therapiestrategien basieren auf den Erfahrungen bei kleinzelligen Karzinomen der Lunge. 0,5â% aller KNK treten im Kopf-Hals-Bereich auf. In unserer Klinik wurden in 12 Jahren 9 KNK diagnostiziert, 2 davon mit laryngealer Manifestation. Wir berichten ĂŒber einen 29-jĂ€hrigen Patienten mit Erstdiagnose (ED) eines Larynx-KNK im FrĂŒhjahr 2018. Im Staging zeigten sich zervikale Lymphknotenmetastasen, eine Fernmetastasierung wurde ausgeschlossen. Es erfolgte eine pRCT mit Cisplatin/Etoposid mit darauffolgender Komplettremission. Im Re-Staging 6 Monate nach ED zeigten sich Metastasen-suspekte Lungenherde. Unter 6 Zyklen palliativer Systemtherapie mit Cyclophosphamid, Adriamycin und Vincristin kam es zu einer partiellen Remission. Nach 12 Monaten erfolgte bei Progress die Therapieumstellung auf den PD-1-Antikörper Nivolumab. Der Patient verstarb 22 Monate nach ED an einer tumorbedingten Massenblutung mit Verlegung der Atemwege.
SchlussfolgerungâBisher existieren keine Studienergebnisse ĂŒber den Einsatz von Nivolumab als Third-Line-Therapie bei KNK. Die Analyse einer NTRK-Fusion (neurotrophe Tyrosin-Rezeptor-Kinase) oder einer Folatrezeptor-Expression sollte erwogen werden zur Evaluation einer Tropomyosin-Rezeptor-Kinase-Inhibitor- oder einer Radionuklidtherapie
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