Electrode effects on the observability of destructive quantum interference in single-molecule junctions

Destructive quantum interference (QI) has been a source of interest as a new paradigm for molecular electronics as the electronic conductance is widely dependent on the occurrence or absence of destructive QI effects. In order to interpret experimentally observed transmission features, it is necessary to understand the effects of all components of the junction on electron transport. We perform non-equilibrium Green's function calculations within the framework of density functional theory to assess the structure-function relationship of transport through pyrene molecular junctions with distinct QI properties. The chemical nature of the anchor groups and the electrodes controls the Fermi level alignment, which determines the observability of destructive QI. A thorough analysis allows to disentangle the transmission features arising from the molecule and the electrodes. Interestingly, graphene electrodes introduce features in the low-bias regime, which can either mask or be misinterpreted as QI effects, while instead originating from the topological properties of the edges. Thus, this first principles analysis provides clear indications to guide the interpretation of experimental studies, which cannot be obtained from simple H\"uckel model calculations.Comment: 12 pages, 8 figure

Dynamic Transitions for Quasilinear Systems and Cahn-Hilliard equation with Onsager mobility

The main objectives of this article are two-fold. First, we study the effect of the nonlinear Onsager mobility on the phase transition and on the well-posedness of the Cahn-Hilliard equation modeling a binary system. It is shown in particular that the dynamic transition is essentially independent of the nonlinearity of the Onsager mobility. However, the nonlinearity of the mobility does cause substantial technical difficulty for the well-posedness and for carrying out the dynamic transition analysis. For this reason, as a second objective, we introduce a systematic approach to deal with phase transition problems modeled by quasilinear partial differential equation, following the ideas of the dynamic transition theory developed recently by Ma and Wang

High-Risk Artificial Intelligence Systems under the European Union’s Artificial Intelligence Act: Systemic Flaws and Practical Challenges

The European Union’s (EU) Artificial Intelligence Act (EU AI Act) has adopted a risk-based approach to artificial intelligence (AI) regulation, where AI systems are subjected to different regulatory standards depending on the seriousness of the risk they pose to public interest. High-risk AI systems, the largest category, are subject to strict regulatory requirements imposed throughout their life cycle, ranging from comprehensive conformity assessment to human rights impact assessment and risk management systems. However, the EU AI Act’s high-risk classification system has two systemic fundamental flaws that undermine its ability to strike a fair balance between the risks of various uses of AI technologies and their societal benefits. First, it defines high-risk AI systems through hyper-technical enumeration, potentially excluding certain AI systems from the high-risk category, even if they pose significant risks to public interest. The Act grants the European Commission the power to revise the high-risk category by adding new AI use cases to the list, if they pose similar or greater risks as the existing ones. But the Commission’s power to revise the list does not adequately address the potential loopholes to be created by the restrictive method of defining high-risk AI systems. Second, due to its failure to consider the specific contexts in which AI technologies are used, the EU AI Act could impose disproportionate regulatory burdens on providers and deployers by improperly classifying their AI use cases as high-risk. By using practical examples based on assessment of several real-world use cases of AI technologies conducted in July 2023 during the St. Gallen University First Grand Challenge on the EU AI Act, this paper argues that the EU AI Act requires revision to adequately regulate AI technologies. The paper proposes a solution to address the EU AI Act’s shortcomings, based on the way the law defines high-risk in the context of data protection impact assessment

A survey of adaptive services to cope with dynamics in wireless self-organizing networks

In this article, we consider different types of wireless networks that benefit from and, in certain cases, require self-organization. Taking mobile ad hoc, wireless sensor, wireless mesh, and delay-tolerant networks as examples of wireless self-organizing networks (WSONs), we identify that the common challenges these networks face are mainly due to lack of centralized management, device heterogeneity, unreliable wireless communication, mobility, resource constraints, or the need to support different traffic types. In this context, we survey several adaptive services proposed to handle these challenges. In particular, we group the adaptive services as core services and network-level services. By categorizing different types of services that handle adaptation and the types of adaptations, we intend to provide useful design guidelines for achieving self-organizing behavior in network protocols. Finally, we discuss open research problems to encourage the design of novel protocols for WSONs.</jats:p

Preliminary outcomes of five-year survival for ovarian malignancies in profiled Serbian Oncology Centre

Objective: The present study purposed to determine characteristics of ovarian carcinoma and to analyze predictors of survival in patients with ovarian carcinoma. Method: A retrospective cohort study was conducted including the patients with diagnosed ovarian carcinoma treated at the Clinic for Operative Oncology, Oncology Institute of Vojvodina in the period from January&nbsp;2012 to December&nbsp;2016. Seventy-two women with ovarian carcinoma were included in the analysis. The data about the histological type of tumor, disease stage, treatment, lymphatic infiltration, and surgical procedure were collected retrospectively, using the database of the institution where the research was conducted (BirPis&nbsp;21 SRC Infonet DOO ‒ Information System Oncology Institute of Vojvodina). Descriptive statistics and multivariate analysis using Cox proportional hazards model were performed. Results: The univariate Cox regression analysis identified histology, tumor grade, FIGO (International Federation of Gynecology and Obstetrics) stage, NACT (Neoadjuvant Chemotherapy), number of therapy cycles, type of surgery, and chemotherapy response as independent predictors of mortality. Finally, the type of tumor and chemotherapy response had an increased hazard ratio for mortality in the multivariate Cox regression model. Herewith, the percentage of high-grade, advanced-stage ovarian cancer patients with complete response to chemotherapy, absence of recurrent disease, and lymphovascular space invasion were significant predictors of survival in patients with ovarian carcinoma. Conclusions: Herein, emerging data regarding precision medicine and molecular-based personalized treatments are promising and will likely modify the way the authors provide multiple lines of treatments in the near future

Programmed cell death-1 and its ligands: Current knowledge and possibilities in immunotherapy

Programmed Cell Death-1 (PCD-1) is a key immune checkpoint receptor, which mainly expresses on activated T, B, Dendritic (DC), Natural Killer (NK), and Treg cells. On the surface of activated T-cells, PCD-1 expression is upregulated after the recognition of peripherals antigens by T cells; subsequently, the elevated binding of PD-1 to Programmed Death Ligand-1 (PD-L1) and Programmed Death Ligand-2 (PD-L2) becomes a key step for downstream inhibitory signaling. Although the role of PD-L1 has been evaluated more thoroughly by clinical research, and PD-L1 has also been used more widely in the clinical setting, PD-L2 also plays an important role in the negative regulation of T-cells, one of the necessary conditions that lead to immune tolerance. Expression of PD-L1 either in tumors or in infiltrating immune cells has been verified predominantly by Immunohistochemistry (IHC) in a variety of tumors, suggesting a role for the PD-1/PD-L1 axis as a prognostic trait and therapeutic target across multiple histotypes. The complex interplay between these factors plays a major role in the diffusion and clinical application of PD-L1 IHC assays as predictive biomarkers of response to PD-1/PD-L1 inhibitors. Checkpoint blockades are registered for the treatment of various cancers, including gynecological malignancies