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Patients with Marfan syndrome often have severe life-threatening cardiovascular complications, including aortic aneurysmal dilatation or aortic dissection. Approximately two-thirds of people who have this syndrome suffer from chest wall deformities such as pectus excavatum (cobbler's chest) or pectus carinatum (bird's chest). When a patient with cobbler's chest requires aortic root surgery, the operator may face a major clinical challenge in selecting the optimal surgical access and approach. We present a case of a patient with Marfan syndrome and severe pectus excavatum who underwent aortic valve replacement, aortic root and ascending aorta reconstruction, coronary artery reimplantation (Bentall de Bono procedure ) via upper partial L-sternotomy and anterior left thoracotomy.

Introduction The EXPERIENCE project aims to enable the creation and sharing of extended-personal realities in virtual reality (VR). Currently, software and hardware technology are under development, that will automatically generate VR environments based on neurophysiological, psychological, cognitive, and behavioral data to support not only the recording of personal experiences but the transmission as well to another user. Potential use cases include enhanced treatment and the assessment of symptom severity of affective disorders. Objectives The objective is to design and create a virtual reality environment that enables the identification of between-group differences in behavioral measures when comparing depressed and healthy-control participants. Methods We conducted a literature review to identify measures that can be implemented in VR and have the potential to show differences between depressed and healthy-control participants. PubMed and ResearchGate databases were screened to identify potential cognitive tasks. A selection protocol was developed considering effect size, homogeneity of results, risk for cybersickness, cognitive demand, domain heterogeneity, and VR compatibility to choose 4 out of the 47 initial tasks. In addition to the cognitive tasks, behavior measures were considered as well and a virtual environment has been equipped to assess (1) exploratory behavior; (2) engagement with emotionally valenced stimuli (via eye-tracking); (3) metacognitive sensitivity, (4) persistence/grit, and (5) possible effects of mood induction. Results Based on the above review, a virtual environment has been developed which is composed of four rooms and a hallway where the starting point is. After an initial tutorial on how the environment/controllers work participants are free to explore and instructions are only provided for the specific cognitive tasks which have to be solved to open the doors and move between rooms. The rooms are equipped with numerous interactive objects and images with varying emotional valence. The engagement with the environment and general activity are continuously recorded and can be retrieved for analyses after participants exit the environment. Conclusions If the controlled VR environment will be proven effective for the assessment of depressive symptoms in future studies, the EXPERIENCE system could incorporate direct and objective behavioral measures into the assessment depressive symptoms. Consequently, the system has the potential to support the clinical diagnosis of affective disorders. Acknowledgement The EXPERIENCE project is funded by the European Commission H2020 Framework Program with the Grant No. 101017727. Disclosure of Interest None Declared

It is known that there are no local scalar Lie fields in more than two dimensions. Bilocal fields, however, which naturally arise in conformal operator product expansions, do generate infinite Lie algebras. It is demonstrated that these Lie algebras of local observables admit (highly reducible) unitary positive energy representations in a Fock space. The multiplicity of their irreducible components is governed by a compact gauge group. The mutually commuting observable algebra and gauge group form a dual pair in the sense of Howe. In a theory of local scalar fields of conformal dimension two in four space-time dimensions the associated dual pairs are constructed and classified.The paper reviews joint work of B. Bakalov, N. M. Nikolov, K.-H. Rehren and the author.

Abstract Introduction The final aim of the EXPERIENCE project is to enable individuals to record and share extended-personal realities in Virtual Reality (VR) - which entails the consideration of a person’s neurophysiological, psychological, and cognitive states. One prospective application is using this technology to aid in assessing symptoms of affective disorders. Objectives The objective is to test the ability of a pre-designed VR environment to differentiate between individuals with depressive symptoms and healthy controls (HCs) via machine learning algorithms. Methods Conducted as a pilot study in Italy, we recruited 100 volunteers, comprising 50 HCs and 50 individuals with moderate depressive symptoms assessed via the PHQ-9. Through a 40–60-minute VR engagement, comprehensive data on cognitive (inc. cognitive flexibility, sustained attention, working memory, processing speed), behavioral (exploration, attentional bias), and physiological (heart-rate variability, skin conductance) variables was collected. Subsequently, an explainable artificial intelligence model (xAI) was trained on data from 80% of the sample and tested on the remaining 20% in terms of accuracy for between-group classification. Results Following an iterative process that considered both the importance assigned to each variable in the different models and the theoretical relevance of these variables to depression the final model achieved an average accuracy of 71% (with individual trials ranging from 64.5% to 77.1%). Key predictors included exploratory behaviors and heart-rate variability during both exploration and cognitive tasks. Conclusions These results are comparable, however remain below the levels of accuracy achieved based on fMRI and DTI data alone (around 80%). Nonetheless, the EXPERIENCE system, slated for refinement beyond this pilot phase, shows potential in integrating multimodal data for evaluating affective disorder symptoms, aiming for a more objective screening and diagnostic approach at a lower cost. Acknowledgement The EXPERIENCE project is funded by the European Commission H2020 Framework Program, Grant No. 101017727. Disclosure of Interest None Declared

In this study we report depleted uranium (DU) analysis in whole blood samples. Internal exposure to DU causes increased uranium levels as well as change in the uranium isotopic composition in blood specimen. For identification of DU exposure we used the 235U/238U ratio in blood samples, which ranges from 0.00725 for natural uranium to 0.002 for depleted uranium. Uranium quantification and isotopic composition analysis were performed by inductively coupled plasma mass spectrometry. For method validation we used eight spiked blood samples with known uranium concentrations and isotopic composition. The detection limit for quantification was determined to be 4 ng L−1uranium in whole blood. The data reproduced within 1–5% RSD and an accuracy of 1–4%. In order to achieve a 235U/238U ratio range of 0.00698–0.00752% with 99.7% confidence limit a minimum whole blood uranium concentration of 60 ng L¬1was required. An additional 10 samples from a cohort of veterans exposed to DU in Gulf War I were analyzed with no knowledge of their medical history. The measured 235U/238U ratios in the blood samples were used to identify the presence or absence of DU exposure within this patient group. [ABSTRACT FROM AUTHOR]

A crucial and important factor for successful treatment of burns is the early covering of the burned area with skin substitutes. The covering of the burn re-quires material that restores the epidermal function and integrates itself into the process of healing. Biological dressings are the golden standard for the temporary covering of burns. All biological skin substitutes are susceptible to early graft reaction and the only exception is the amnion membrane. The importance of the amnion membrane as a bio-logical dressing for burns amounts to: a barrier to bacterial colonization, hastens the epithelisation, and control of water loss. Amnioplasty is a method of application of amnion membrane on the recipient site. In this comparative study, 60 patients with dermal and sub-dermal burns were included. Research was made on an examination group of 30 patients with burns where the method of amnioplasty was applied, and for this amnion membrane conserved in 76% alcohol was used. The control group was made up of 30 patients with burns treated conventionally, and standard methods for the local treatment of burns were applied: exposition, occlusive dressing and initial excision with skin grafting. Pathohistological and microbiological analyses of the bioptical material were made. The degree of the burns was determined through a pathohistological analysis of the bioptical material taken the third day, and in some of the subjects where re-epithelialization was determined on the seventh day, the further re-epithelialization was observed clinically. Pathohistological examination enabled discrimination between bacterial colonization and the invasive bacterial infection. Furthermore, the type of bacterial colonization and infection was determined, which was confirmed with microbiological analysis. The analysis of the results from the microbiological and pathohistological researches of the bioptical material according to the bacterial colonization and infection showed that, although between the examined and the control group there was no statistically important difference, the value of p = 0.067 is close to the statistically important value of p < 0.05. The results of the pathohistological examination of the bioptical material taken the seventh day and analysed according to the re-epithelialization showed that there was a significant difference between the two groups of p < 0.035. It should be mentioned that, although according to the microbiological examinations of the bioptical material a statistically significant difference was not achieved, clinical significance was achieved. The obtained significance of p < 0.035 compared to the re-epithelialization in both groups approved the application of the method of amnioplasty. The histological analysis of the bioptical material not only determines the degree of the burns specifically, but facilitates the choice of method for further treatment, observes the speed of the re-epithelialization and plays an important part in the correct diagnosis and the early start of the specific therapy, important in preventing sepsis. The application of amnion membrane as a biological dressing speeds the re-epithelialization and prevents invasive bacterial infection. Pathohistological examination of the burns is recommended to be established as a standard method in clinical practice. [ABSTRACT FROM AUTHOR]

We generalize Deddens' theorem for nest algebras in the case of w*-closed nest algebras bimodules. For each such bimodule, we introduce a norm closed sub-bimodule of it, which corresponds to the radical of a nest algebra and describe it in a number of ways, generalizing known facts about nest algebras. [ABSTRACT FROM AUTHOR]

Abstract  We relate the convergence of a net of maximal Abelian selfadjoint algebras (masas) to that of the net of their corresponding supports. This is achieved by using a family of capacities on the collection of subsets of X × Y (where the masas are realized as collections of operators of multiplication by essentially bounded functions on the measure spaces X and Y), which extends a capacity studied previously by Haydon and Shulman. [ABSTRACT FROM AUTHOR]

In this study, we explore the functional role of striatal cholinergic interneurons, hereinafter referred to as tonically active neurons (TANs), via computational modeling; specifically, we investigate the mechanistic relationship between TAN activity and dopamine variations and how changes in this relationship affect reinforcement learning in the striatum. TANs pause their tonic firing activity after excitatory stimuli from thalamic and cortical neurons in response to a sensory event or reward information. During the pause striatal dopamine concentration excursions are observed. However, functional interactions between the TAN pause and striatal dopamine release are poorly understood. Here we propose a TAN activity-dopamine relationship model and demonstrate that the TAN pause is likely a time window to gate phasic dopamine release and dopamine variations reciprocally modulate the TAN pause duration. Furthermore, this model is integrated into our previously published model of reward-based motor adaptation to demonstrate how phasic dopamine release is gated by the TAN pause to deliver reward information for reinforcement learning in a timely manner. We also show how TAN-dopamine interactions are affected by striatal dopamine deficiency to produce poor performance of motor adaptation.

Motor adaptation to perturbations is provided by learning mechanisms operating in the cerebellum and basal ganglia. The cerebellum normally performs motor adaptation through supervised learning using information about movement error provided by visual feedback. However, if visual feedback is critically distorted, the system may disengage cerebellar error-based learning and switch to reinforcement learning mechanisms mediated by basal ganglia. Yet, the exact conditions and mechanisms of cerebellum and basal ganglia involvement in motor adaptation remain unknown. We use mathematical modeling to simulate control of planar reaching movements that relies on both error-based and non-error-based learning mechanisms. We show that for learning to be efficient only one of these mechanisms should be active at a time. We suggest that switching between the mechanisms is provided by a special circuit that effectively suppresses the learning process in one structure and enables it in the other. To do so, this circuit modulates learning rate in the cerebellum and dopamine release in basal ganglia depending on error-based learning efficiency. We use the model to explain and interpret experimental data on error- and non-error-based motor adaptation under different conditions.

As an RNA virus, hepatitis C virus (HCV) is able to rapidly acquire drug resistance, and for this reason the design of effective anti-HCV drugs is a real challenge. The HCV subgenomic replicon-containing cells are widely used for experimental studies of the HCV genome replication mechanisms, for drug testing in vitro and in studies of HCV drug resistance. The NS3/4A protease is essential for virus replication and, therefore, it is one of the most attractive targets for developing specific antiviral agents against HCV. We have developed a stochastic model of subgenomic HCV replicon replication, in which the emergence and selection of drug resistant mutant viral RNAs in replicon cells is taken into account. Incorporation into the model of key NS3 protease mutations leading to resistance to BILN-2061 (A156T, D168V, R155Q), VX-950 (A156S, A156T, T54A) and SCH 503034 (A156T, A156S, T54A) inhibitors allows us to describe the long term dynamics of the viral RNA suppression for various inhibitor concentrations. We theoretically showed that the observable difference between the viral RNA kinetics for different inhibitor concentrations can be explained by differences in the replication rate and inhibitor sensitivity of the mutant RNAs. The pre-existing mutants of the NS3 protease contribute more significantly to appearance of new resistant mutants during treatment with inhibitors than wild-type replicon. The model can be used to interpret the results of anti-HCV drug testing on replicon systems, as well as to estimate the efficacy of potential drugs and predict optimal schemes of their usage.