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Quantum interference (QI)—the constructive or destructive interference of conduction pathways through molecular orbitals—plays a fundamental role in enhancing or suppressing charge and spin transport in organic molecular electronics. Graphical models were developed to predict constructive versus destructive interference in polyaromatic hydrocarbons and have successfully estimated the large conductivity differences observed in single-molecule transport measurements. A major challenge lies in extending these models to excitonic (photoexcited) processes, which typically involve distinct orbitals with different symmetries. Here we investigate how QI models can be applied as bridging moieties in intramolecular singlet-fission compounds to predict relative rates of triplet pair formation. In a series of bridged intramolecular singlet-fission dimers, we found that destructive QI always leads to a slower triplet pair formation across different bridge lengths and geometries. A combined experimental and theoretical approach reveals the critical considerations of bridge topology and frontier molecular orbital energies in applying QI conductance principles to predict rates of multiexciton generation.Principles of quantum interference can guide the design of chromophores that undergo singlet fission. Now, ‘pencil and paper’ graphical models can be used to understand and predict the dynamics of triplet pairs generated through singlet fission in bridged dimers.

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In response to the continuing high demand for transportation fuel in the 21st century, microalgae cultivation has emerged as one technology that could supply fuel derived from renewable sources. To ensure proper health and optimal production in a microalgae culture, several environmental parameters such as temperature, pH, dissolved oxygen, nutrient content, and other factors should be monitored continuously. In a large scale cultivation facility, the problem of developing an appropriate instrumentation and control system is compounded by the need to collect sensor information from many different locations simultaneously. In this work, a wireless sensor network is proposed and demonstrated for the measurement of pH, dissolved oxygen, and temperature in a microalgae cultivation system. ISFET (Ion-sensitive field-effect transistor) technology is selected for pH measurement in this system, due to its advantages over traditional glass pH electrodes in durability and stability. The development of this sensor network is described in three main experimental phases: preliminary experimental work, a proof of concept experiment using a single pH sensor, and a performance evaluation using three pH sensors, one temperature sensor, and one dissolved oxygen sensor. The first two phases were designed for and tested at the NASA OMEGA (Offshore Membrane Enclosures for Growing Algae) project, and the third phase, the performance evaluation, took place in the open raceway ponds used for algae cultivation at the University of Nevada, Reno. A full description of each experiment is given, and the performance of the sensor network is described in terms of system reliability and drift characteristics.

Bitcoin is a peer-to-peer cryptographic currency system. Since its introduction in 2008, Bitcoin has gained noticeable popularity, mostly due to its following properties: (1) the transaction fees are very low, and (2) it is not controlled by any central authority, which in particular means that nobody can \"print\" the money to generate inflation. Moreover, the transaction syntax allows to create the so-called contracts, where a number of mutually-distrusting parties engage in a protocol to jointly perform some financial task, and the fairness of this process is guaranteed by the properties of Bitcoin. Although the Bitcoin contracts have several potential applications in the digital economy, so far they have not been widely used in real life. This is partly due to the fact that they are cumbersome to create and analyze, and hence risky to use. In this paper we propose to remedy this problem by using the methods originally developed for the computer-aided analysis for hardware and software systems, in particular those based on the timed automata. More concretely, we propose a framework for modeling the Bitcoin contracts using the timed automata in the UPPAAL model checker. Our method is general and can be used to model several contracts. As a proof-of-concept we use this framework to model some of the Bitcoin contracts from our recent previous work. We then automatically verify their security in UPPAAL, finding (and correcting) some subtle errors that were difficult to spot by the manual analysis. We hope that our work can draw the attention of the researchers working on formal modeling to the problem of the Bitcoin contract verification, and spark off more research on this topic.

BitCoin transactions are malleable in a sense that given a transaction an adversary can easily construct an equivalent transaction which has a different hash. This can pose a serious problem in some BitCoin distributed contracts in which changing a transaction's hash may result in the protocol disruption and a financial loss. The problem mostly concerns protocols, which use a \"refund\" transaction to withdraw a deposit in a case of the protocol interruption. In this short note, we show a general technique for creating malleability-resilient \"refund\" transactions, which does not require any modification of the BitCoin protocol. Applying our technique to our previous paper \"Fair Two-Party Computations via the BitCoin Deposits\" (Cryptology ePrint Archive, 2013) allows to achieve fairness in any Two-Party Computation using the BitCoin protocol in its current version.

Immunotherapy failures can result from the highly suppressive tumour microenvironment that characterizes aggressive forms of cancer such as recurrent glioblastoma (rGBM) 1 , 2 . Here we report the results of a first-in-human phase I trial in 41 patients with rGBM who were injected with CAN-3110—an oncolytic herpes virus (oHSV) 3 . In contrast to other clinical oHSVs, CAN-3110 retains the viral neurovirulence ICP34.5  gene transcribed by a nestin promoter; nestin is overexpressed in GBM and other invasive tumours, but not in the adult brain or healthy differentiated tissue 4 . These modifications confer CAN-3110 with preferential tumour replication. No dose-limiting toxicities were encountered. Positive HSV1 serology was significantly associated with both improved survival and clearance of CAN-3110 from injected tumours. Survival after treatment, particularly in individuals seropositive for HSV1, was significantly associated with (1) changes in tumour/PBMC T cell counts and clonal diversity, (2) peripheral expansion/contraction of specific T cell clonotypes; and (3) tumour transcriptomic signatures of immune activation. These results provide human validation that intralesional oHSV treatment enhances anticancer immune responses even in immunosuppressive tumour microenvironments, particularly in individuals with cognate serology to the injected virus. This provides a biological rationale for use of this oncolytic modality in cancers that are otherwise unresponsive to immunotherapy (ClinicalTrials.gov: NCT03152318 ). Treatment with the oncolytic herpes virus CAN-3110 is associated with improved survival responses in patients with recurrent glioblastoma, particularly in individuals who are seropositive for HSV1.

Light-induced magnetisation switching is one of the most intriguing and promising areas where an ultrafast phenomenon can be utilised in technological applications. So far, experiment and theory have considered the origin of all-optical helicity-independent magnetisation switching (AO-HIS) in individual magnetic films only as a microscopically local, thermally-driven process of angular momentum transfer between different subsystems. Here, we demonstrate that this local picture is insufficient and that AO-HIS must also be regarded as a spatially inhomogeneous process along the depth within a few-nanometre thin magnetic layer. Two regions of opposite magnetisation directions are observed, separated by a highly mobile boundary, which propagates along the depth of a 9.4 nm thin Gd 25 Co 75 alloy. The dynamics of this transient boundary determines the final magnetisation state as well as the speed of AO-HIS throughout the entire magnetic layer. The ability to understand the influence of nanoscale and transient inhomogeneities on ultrafast switching phenomena and more generally on phase transitions will open new routes for material design and excitation scenarios in future devices for transferring and storing information. The authors reveal that even within a few-nanometre thin films, ultrafast all-optical magnetisation switching is spatially inhomogeneous along the depth and driven by the picosecond propagation of a transient domain boundary.

This paper presents the investigation of the effect of electron radiation or the combined action of this radiation and triallyl isocyanurate (TAIC) on the structural, thermal, and mechanical properties of epoxy resin filled with a fraction of dust fibers (DFs) from recycled wind turbine blades. The resin containing 20 wt% of DF was irradiated with doses of 40, 80, 120, and 160 kGy. The results showed that electron radiation had only a slight effect on the properties of the studied composite, mainly on its glass transition temperature. More significant changes were observed with the combined action of radiation and TAIC. The main effect that occurred after the TAIC addition was the plasticization of the polymer matrix. With its participation, the glass transition temperature, thermal stability, and the hardness of the material and its flexural modulus were significantly reduced. The degree of change in these properties was regulated by the radiation dose. Furthermore, no significant changes in the composite structure were observed after radiation treatment, while the introduction of TAIC into the polymer matrix caused the formation of gas cells, probably due to the partial decomposition of TAIC.

The aim of this study was to ascertain whether the combined action of metal nanoparticles (silver, copper, zinc oxide, iron oxide) would ensure the appropriate biocidal properties oflow-density polyethylene (LDPE) against pathogenic microorganisms. According to the research hypothesis, appropriately selected concentrations of the applied metal nanoparticles allow for a high level of biocidal activity of polymeric materials against both model and pathogenic bacterial strains (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Legionella pneumophila, Salmonella enterica subsp. enterica) and fungi (Aspergillus brasiliensis, Saccharomyces cerevisiae, Candida albicans, Penicilium expansum), whilst ensuring the safety of use due to the lack of migration of particles to the surrounding environment. Studies have shown that adding 4% of a biocide containing Ag, Cu, ZnO, and Fe2O3 nanoparticles is the most optimal solution to reduce the number of S. aureus, S. enterica and P. aeruginosa by over 99%. The lowest effectiveness was observed against L. pneumophila bacteria. As for E. coli, a higher biocide content did not significantly increase the antibacterial activity. The results showed a high efficiency of the applied biocide at a concentration of 2% against fungal strains. The high efficiency of the obtained biocidal results was influenced by the uniform dispersion of nanoparticles in the material and their low degree of agglomeration. Furthermore, a slight migration of components to the environment is the basis for further research in the field of the application of the developed materials in industry.

The search for waste management opportunities is crucial for achieving environmentally friendly waste practices and ensuring the country’s energy security. This research aimed to valorize biomass and waste generated in greenhouses and to analyze the potential for electricity production from this waste. The analyses compared the situations in Turkey and Poland, where greenhouse production of vegetables is developing and constitutes an important link in agricultural activities, despite differences in climatic conditions. The cultivation of vegetables and flowers under cover is rapidly expanding in both countries and, with changing climatic conditions, is expected to shape the future of agriculture. In addition to estimating the energy that can be obtained, the study also evaluated the economic benefits of such a solution and the volume of avoided CO2 emissions from fossil fuels. The issue of utilizing these wastes is significant because current methods of their management do not lead to energy production, so their considerable energy potential is wasted, as highlighted in this study. Moreover, there is a lack of similar studies in the literature. The plant species chosen as materials in this study were tomatoes, peppers, eggplant, watermelon, and melon in the case of Turkey. For Poland, the analysis was conducted for tomatoes and greenhouse cucumbers. These crops represent the largest cultivated areas under cover in the respective countries. Results indicated that the average yearly amount of vegetable residue is approximately 463 thousand Mg in Turkey, and 77 thousand Mg in Poland. The estimated annual electricity potential is 430 GWh in Turkey and 80 GWh in Poland. Considering the efficiency of power generation in a typical power plant, the real amount of electricity to be obtained is 0.46 MWh per Mg of waste in Turkey and 0.52 MWh in Poland.