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Detection and mapping of Sosnowsky's hogweed (HS) using remote sensing data have proven effective, yet challenges remain in identifying, localizing, and eliminating HS in urban districts and regions. Reliable data on HS growth areas are essential for monitoring, eradication, and control measures. Satellite data alone are insufficient for mapping the dynamics of HS distribution. Unmanned aerial vehicles (UAVs) with high-resolution spatial data offer a promising solution for HS detection and mapping. This study aimed to develop a method for detecting and mapping HS growth areas using a proposed algorithm for thematic processing of multispectral aerial imagery data. Multispectral data were collected using a DJI Matrice 200 v2 UAV (Dajiang Innovation Technology Co., Shenzhen, China) and a MicaSense Altum multispectral camera (MicaSense Inc., Seattle, WA, USA). Between 2020 and 2022, 146 sites in the Moscow region of the Russian Federation, covering 304,631 hectares, were monitored. Digital maps of all sites were created, including 19 digital maps (orthophoto, 5 spectral maps, and 13 vegetation indices) for four experimental sites. The collected samples included 1080 points categorized into HS, grass cover, and trees. Student's t-test showed significant differences in vegetation indices between HS, grass, and trees. A method was developed to determine and map HS-growing areas using the selected vegetation indices NDVI > 0.3, MCARI > 0.76, user index BS1 > 0.10, and spectral channel green > 0.14. This algorithm detected HS in an area of 146.664 hectares. This method can be used to monitor and map the dynamics of HS distribution in the central region of the Russian Federation and to plan the required volume of pesticides for its eradication. [ABSTRACT FROM AUTHOR]

Synthesis of highly porous ceramic materials for catalytic converters based on coarse-dispersed αAl2O3 using a combination of compaction and thermochemical synthesis with the participation of active ultrafine binders is carried out. Using X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM), it is established that the morphology of the synthesized material simultaneously includes large pores between filler particles (dominant αAl2O3 phase) and submicron pores in transboundary regions that appeared during the processes of liquid-phase sintering and gas evolution. A significant amount of indialite (Mg2Al4Si5O18) and spinel (MgAl2O4) formed as a result of thermochemical synthesis on surfaces and in the gaps between coarse-dispersed particles is revealed. The dominant pore size (according to the volume of mercury intrusion) is from 20 to 60 μm (about 73%), as well as pores with size from 0.4 to 2 μm (about 6%).The average pore size is about 9 μm. Highly porous materials with these characteristics of the pore space can be effectively used after modification as catalytic converters for the dehydrogenation of alkyl aromatic hydrocarbons with large molecular sizes (about 400 nm) with a long mean free path on the order of ~3–4 μm. [ABSTRACT FROM AUTHOR]

We have calculated the time constants of the electron dynamics in traps in a metal–insulator–metal (MIM) plasmonic structure. Because of electron relaxation in metal, the surface plasmon polaritons decays into hot electrons near the surface of the metal, which facilitates the trap of electrons in the interfacial layer of the dielectric. We have calculated the capture and emission times separately as the electron does not follow the same mechanisms with the capture process when it is emitted from a trap at the metal/oxide interface. We have developed a quasi-two-dimensional treatment that has been modified from a previously used semiconductor/oxide junction by using Bardeen's function to calculate the capture time. Various parameters including trap's distance from the interface, temperature, voltage bias, and spectral nature of the hot electrons' energy distribution influence the interaction between a plasmonic hot electron and a neutral near-interface trap in the capture process. On the one hand, the emission time is independent of the capture time, and it is determined by the tunneling time to the metal depending on the temperature and the energy difference between the trap energy levels (ground and excited states). We have showed that a wide range of capture times from seconds to picoseconds is possible for an interfacial trap at the room temperature due to the spectral energy distribution of hot electrons and dependence of the capture process on the losses in metals. On the other hand, the temperature plays the dominant role in the emission time. For the trap with 250 meV energy difference between its levels, the emission time is in the range of picosecond at room temperature. Therefore, the MIM plasmonic device can respond to a wide range of ac voltage frequencies including the ultra-fast domain. These interesting findings are useful to understand the ac response of the MIM plasmonic devices with applications in integrated photonics and ultra-fast optoelectronics. [ABSTRACT FROM AUTHOR]

In this paper, we extend Open-set Semantic Segmentation (OSS) into a new image segmentation task called Generalized Open-set Semantic Segmentation (GOSS). Previously, with well-known OSS, the intelligent agents only detect unknown regions without further processing, limiting their perception capacity of the environment. It stands to reason that further analysis of the detected unknown pixels would be beneficial for agents' decision-making. Therefore, we propose GOSS, which holistically unifies the abilities of two well-defined segmentation tasks, i.e. OSS and generic segmentation. Specifically, GOSS classifies pixels as belonging to known classes, and clusters (or groups) of pixels of unknown class are labelled as such. We propose a metric that balances the pixel classification and clustering aspects to evaluate this newly expanded task. Moreover, we build benchmark tests on existing datasets and propose neural architectures as baselines. Our experiments on multiple benchmarks demonstrate the effectiveness of our baselines. Code is made available at https://github.com/JHome1/GOSS_Segmentor. [ABSTRACT FROM AUTHOR]

Background. MRI is an important tool for accurate detection and targeted biopsy of prostate lesions. However, the imaging appearances of some prostate cancers are similar to those of the surrounding normal tissue on MRI, which are referred to as MRI-invisible prostate cancers (MIPCas). The detection of MIPCas remains challenging and requires extensive systematic biopsy for identification. In this study, we developed a weakly supervised UNet (WSUNet) to detect MIPCas. Methods. The study included 777 patients (training set: 600; testing set: 177), all of them underwent comprehensive prostate biopsies using an MRI-ultrasound fusion system. MIPCas were identified in MRI based on the Gleason grade (≥7) from known systematic biopsy results. Results. The WSUNet model underwent validation through systematic biopsy in the testing set with an AUC of 0.764 (95% CI: 0.728-0.798). Furthermore, WSUNet exhibited a statistically significant precision improvement of 91.3% (p < 0.01) over conventional systematic biopsy methods in the testing set. This improvement resulted in a substantial 47.6% (p < 0.01) decrease in unnecessary biopsy needles, while maintaining the same number of positively identified cores as in the original systematic biopsy. Conclusions. In conclusion, the proposed WSUNet could effectively detect MIPCas, thereby reducing unnecessary biopsies. [ABSTRACT FROM AUTHOR]

A novel approach for video instance segmentation is presented using semisupervised learning. Our Cluster2Former model leverages scribble-based annotations for training, significantly reducing the need for comprehensive pixel-level masks. We augment a video instance segmenter, for example, the Mask2Former architecture, with similarity-based constraint loss to handle partial annotations efficiently. We demonstrate that despite using lightweight annotations (using only 0.5% of the annotated pixels), Cluster2Former achieves competitive performance on standard benchmarks. The approach offers a cost-effective and computationally efficient solution for video instance segmentation, especially in scenarios with limited annotation resources. [ABSTRACT FROM AUTHOR]

Mobility is an important parameter to estimate the performance of organic thin‐film transistors, one of the key factors affecting the mobility is the first several semiconductors molecular layers near the insulator surface. A strategy is proposed to introduce aromatic‐rings in the gate insulating layer to modulate the growth of pentacene, thus a series of aryl group containing polymers by reversible‐addition‐fragmentation chain‐transfer polymerization is synthesized for the preparation of organic thin‐film transistor insulators. The semiconductor layer is evaporated on the polymer insulators at room temperature. As the inducing function of the aromatic ring, greater weak interactions between dielectric materials and semiconductors by simulation, which makes the initial pentacene layer weak epitaxial growth, therefore pentacene could form better morphology, especially larger crystal domains and uniform thin‐film continuity. The results show that precision design and synthesis of polymer insulator layers provide new methods to achieve high performance of organic thin‐film transistors with easier fabricating process. [ABSTRACT FROM AUTHOR]

This article discusses the concept of ion trapping using a mechanical Paul trap, which was first introduced by Nobel laureate Wolfgang Paul in the 1950s. The mechanical Paul trap is a 3D-printed device that can be used to demonstrate and investigate the physical phenomena of ion trapping. The article provides information on the design and construction of the mechanical Paul trap, as well as student investigations that can be conducted using the trap. The investigations focus on topics such as the physical properties of a saddle point and the effects of varying frequency on trapping. The article emphasizes the pedagogical value of the mechanical Paul trap in teaching students about ion trapping and field strength. [Extracted from the article]

On the basis of developed individual-based model and empirical data the importance of anemochory for the dispersal of giant hogweed mericarpia over long distances (up to 55 m from the parent plant) was proved. The use of cellular automate for modelling of the plant population area increase allowed to reveal the influence of weather condition, number and spatial distribution of hogweed plants in the period of the beginning of introduction on the rate of invasion. Verification of the results of the cellular automaton work based on satellite images and field observations showed a significant level of compliance of theoretical calculations and observed results. The logistic functions parameters describing the change in the area of giant invasive hogweed stands were determined. A retrospective analysis of satellite images of model plots, starting from the 1990s of the 20th century, showed an annual increase in the area of hogweed populations by 20% in the exponential population growth phase. A significant variability in the rate of invasion (from 5 to 70% per year) depended on the initial conditions and stage of invasion, usage modes and ecological capacity of the available sites. [ABSTRACT FROM AUTHOR]

The phenomenon of oscillatory instability called 'flutter' was observed in aeroelasticity and rotor dynamics about a century ago. Driven by a series of applications involving non-conservative elasticity theory at different physical scales, ranging from nanomechanics to the mechanics of large space structures and including biomechanical problems of motility and growth, research on flutter is experiencing a new renaissance. A review is presented of the most notable applications and recent advances in fundamentals, both theoretical and experimental aspects, of flutter instability and Hopf bifurcation. Open problems, research gaps and new perspectives for investigations are indicated. [ABSTRACT FROM AUTHOR]

A variety of ribo-, 2′-deoxyribo-, and 5′-norcarbocyclic derivatives of the 8-aza-7-deazahypoxanthine fleximer scaffolds were designed, synthesized, and screened for antibacterial activity. Both chemical and chemoenzymatic methods of synthesis for the 8-aza-7-deazainosine fleximers were compared. In the case of the 8-aza-7-deazahypoxanthine fleximer, the transglycosylation reaction proceeded with the formation of side products. In the case of the protected fleximer base, 1-(4-benzyloxypyrimidin-5-yl)pyrazole, the reaction proceeded selectively with formation of only one product. However, both synthetic routes to realize the fleximer ribonucleoside (3) worked with equal efficiency. The new compounds, as well as some 8-aza-7-deazapurine nucleosides synthesized previously, were studied against Gram-positive and Gram-negative bacteria and M. tuberculosis. It was shown that 1-(β-D-ribofuranosyl)-4-(2-aminopyridin-3-yl)pyrazole (19) and 1-(2′,3′,4′-trihydroxycyclopent-1′-yl)-4-(pyrimidin-4(3H)-on-5-yl)pyrazole (9) were able to inhibit the growth of M. smegmatis mc2 155 by 99% at concentrations (MIC99) of 50 and 13 µg/mL, respectively. Antimycobacterial activities were revealed for 4-(4-aminopyridin-3-yl)-1H-pyrazol (10) and 1-(4′-hydroxy-2′-cyclopenten-1′-yl)-4-(4-benzyloxypyrimidin-5-yl)pyrazole (6). At concentrations (MIC99) of 40 and 20 µg/mL, respectively, the compounds resulted in 99% inhibition of M. tuberculosis growth. [ABSTRACT FROM AUTHOR]

In the present work, the energy donor 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) is used for the first time in combination with a pentacene dimer (Pnc2) to provide the conjugate BODIPYPnc2 that features absorption throughout a large part of the solar spectrum. Upon photoexcitation, the singlet excited state energy of BODIPY is transferred to the pentacene dimer via intramolecular Förster resonance energy transfer (FRET). Subsequently, the pentacene dimer undergoes intramolecular singlet fission. In this process, a singlet correlated triplet pair is generated from the first singlet excited state via coupling to an intermediate state. The results show that solvent polarity has an influence on the system, with the largest FRET rate (i.e., 7.46 × 1011 s−1) being obtained in the most polar solvent (namely, benzonitrile) along with the largest triplet quantum yield (i.e., 207 ± 20%). [ABSTRACT FROM AUTHOR]

Emerging and re-emerging viruses periodically cause outbreaks and epidemics around the world, which ultimately lead to global events such as the COVID-19 pandemic. Thus, the urgent need for new antiviral drugs is obvious. Over more than a century of antiviral development, nucleoside analogs have proven to be promising agents against diversified DNA and RNA viruses. Here, we present the synthesis and evaluation of the antiviral activity of nucleoside analogs and their deglycosylated derivatives based on a hydroxybenzo[4,5]imidazo[1,2-c]pyrimidin-1(2H)-one scaffold. The antiviral activity was evaluated against a panel of structurally and phylogenetically diverse RNA and DNA viruses. The leader compound showed micromolar activity against representatives of the family Coronaviridae, including SARS-CoV-2, as well as against respiratory syncytial virus in a submicromolar range without noticeable toxicity for the host cells. Surprisingly, methylation of the aromatic hydroxyl group of the leader compound resulted in micromolar activity against the varicella-zoster virus without any significant impact on cell viability. The leader compound was shown to be a weak inhibitor of the SARS-CoV-2 RNA-dependent RNA polymerase. It also inhibited biocondensate formation important for SARS-CoV-2 replication. The active compounds may be considered as a good starting point for further structure optimization and mechanistic and preclinical studies. [ABSTRACT FROM AUTHOR]

The mechanisms of the production of vibrationally excited NO and N2 molecules at the altitudes of the middle atmosphere of the Earth during high‐energetic proton precipitation on 20 January 2005 are considered. The study of vibrational populations N2(X1Σg+,v′ > 0) during high‐energetic proton precipitation has shown different principal mechanisms in the N2(X1Σg+,v′ > 0) excitation. First, the excitation by secondary electrons is principal for vibrational levels v′ = 1−10. Second, it is obtained that intramolecular electron energy transfer process in N2(A3Σu+)+N2 collisions dominates in vibrational excitation of high vibrational levels v′ = 20−30. It is shown that the chemical reaction of metastable atomic nitrogen with molecular oxygen is the main production mechanism of vibrationally excited NO(X2Π,v > 0) and of the radiation of 5.3 and 2.7 μm infrared emissions at these altitudes. The calculated intensities of the 5.3 μm emission are compared with experimental data from SABER instrument on TIMED spacecraft received at the time of the proton precipitation. The role of VV′‐processes in the radiation of 5.3 μm infrared emission is discussed. Plain Language Summary: The Ground Level Enhancement on 20 January 2005 is the strongest event of precipitation of energetic protons in the Earth's atmosphere. We study molecular processes at the altitudes of the middle atmosphere during the precipitation. Special attention is paid to a modeling of vibrational kinetics of molecular nitrogen N2 and nitric oxide NO. The influence of electronically excited states of N2 and NO molecules on the vibrational kinetics is considered. The intensities of NO 5.3 and 2.7 μm infrared emissions are calculated. The calculated intensities of the 5.3 μm emission are compared with experimental data from SABER instrument on TIMED spacecraft received at the time of the proton precipitation. Key Points: Vibrational kinetics of NO and N2 in the middle atmosphere during high‐energetic proton precipitation is consideredIntramolecular and intermolecular electron energy transfers are taken into account in calculations of vibrational populations of moleculesIt is shown that there is a dependence of calculated vibrational populations on atmospheric altitude [ABSTRACT FROM AUTHOR]

Polymer semiconductors (PSCs) are essential active materials in mechanically stretchable electronic devices. However, many exhibit low fracture strain due to their rigid chain conformation and the presence of large crystalline domains. Here, a PSC/elastomer blend, poly[((2,6‐bis(thiophen‐2‐yl)‐3,7‐bis(9‐octylnonadecyl)thieno[3,2‐b]thieno[2′,3′:4,5]thieno[2,3‐d]thiophene)‐5,5′‐diyl)(2,5‐bis(8‐octyloctadecyl)‐3,6‐di(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4‐dione)‐5,5′‐diyl]] (P2TDPP2TFT4) and polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene (SEBS) are systematically investigated. Specifically, the effects of molecular weight of both SEBS and P2TDPP2TFT4 on the resulting blend morphology, mechanical, and electrical properties are explored. In addition to commonly used techniques, atomic force microscopy‐based nanomechanical images are used to provide additional insights into the blend film morphology. Opposing trends in SEBS‐induced aggregation are observed for the different P2TDPP2TFT4 molecular weights upon increasing the SEBS molecular weight from 87 to 276 kDa. Furthermore, these trends are seen in device performance trends for both molecular weights of P2TDPP2TFT4. SEBS molecular weight also has a substantial influence on the mesoscale phase separation. Strain at fracture increases dramatically upon blending, reaching a maximum value of 640% ± 20% in the blended films measured with film‐on‐water method. These results highlight the importance of molecular weight for electronic devices. In addition, this study provides valuable insights into appropriate polymer selections for stretchable semiconducting thin films that simultaneously possess excellent mechanical and electrical properties. [ABSTRACT FROM AUTHOR]

The correlations between semiconductor type and gas sensing properties in soluble acene/polymer blends have not yet been examined. Here, the phase separation mechanism in pseudo‐liquid phase blend film is investigated and an unusual solid‐state morphology that is effective for amperometric gas sensing performance is demonstrated. In 6,13‐bis(triisopropylsilylethynyl) pentacene (TIPS–pentacene)/poly(fluorine‐co‐triarylamine) (PTAA) blend, two phases are uniformly mixed, without being completely phase‐separated due to the similar solubility and surface tension. On the other hand, in 2,8‐difluoro‐5,11‐bis(triethylsilylethynyl) anthradithiophene (diF–TES ADT)/PTAA blend, the diF−TES ADT molecules are segregated both at the air–film, and film–substrate interfaces, and subsequently crystallized with a high degree of crystal perfection. In the meanwhile, Marangoni‐flow induces crater‐like via hole structure of PTAA at the middle layer. In situ measurement of (ultraviolet–visible) UV–vis absorption spectra and computational calculation reveal kinetics of liquid–solid–crystal transition in relation to the functional groups of soluble acene. Interestingly, flow driven hole structure of PTAA in diF–TES ADT/PTAA blend film allows the target NO2 gas to selectively penetrate the channel region, thereby enhancing sensitivity toward NO2, while decreasing affinity with other gases. The results provide protocols for fabricating highlperformance field‐effect transistors and gas sensors in a blending system. [ABSTRACT FROM AUTHOR]

Polar ecosystems are the most important storage and source of climatically active gases. Currently, natural biogeochemical processes of organic matter circulation in the soil-atmosphere system are disturbed in urban ecosystems of the cryolithozone. Urbanized ecosystems in the Arctic are extremely under-investigated in terms of their functions in regulating the cycle of climatically active gases. The role of urban soils and soil-like bodies in the sequestration and stabilization of organic matter is of particular interest. The percentage of gravimetric concentrations of organic matter in Arctic urban soils are almost always determined by the method of dichromate oxidation and are subject to extreme variability (from tenths of a percent to more than 90% in man-made soil formations), but the average carbon content in the surface soil horizons can be estimated at 5–7%. The surface humus-accumulative horizons are represented by a variety of morphological forms with the content of organic matter of various origins. The work also focuses on those forms of organic matter, the content of which is extremely small, but very important for the biogeochemical functioning of soils-polycyclic aromatic hydrocarbons and components of petroleum products, as well as labile forms of soil organic matter. We recommend that further studies of the organic matter system be conducted in urbanized areas since the carbon cycle there is severely disrupted, as well as carbon flows. The urbanization and industrialization processes in the Arctic are progressing, which could lead to a radical transformation of carbon ecosystem services. [ABSTRACT FROM AUTHOR]

Background: Patient motions are a repeatedly reported phenomenon in oral and maxillofacial cone beam CT scans, leading to reconstructions of limited usability. In certain cases, independent movements of the mandible induce unpredictable motion patterns. Previous motion correction methods are not able to handle such complex cases of patient movements. Purpose: Our goal was to design a combined motion estimation and motion correction approach for separate cranial and mandibular motions, solely based on the 2D projection images from a single scan. Methods: Our iterative three‐step motion correction algorithm models the two articulated motions as independent rigid motions. First of all, we segment cranium and mandible in the projection images using a deep neural network. Next, we compute a 3D reconstruction with the poses of the object's trajectories fixed. Third, we improve all poses by minimizing the projection error while keeping the reconstruction fixed. Step two and three are repeated alternately. Results: We find that our marker‐free approach delivers reconstructions of up to 85% higher quality, with respect to the projection error, and can improve on already existing techniques, which model only a single rigid motion. We show results of both synthetic and real data created in different scenarios. The reconstruction of motion parameters in a real environment was evaluated on acquisitions of a skull mounted on a hexapod, creating a realistic, easily reproducible motion profile. Conclusions: The proposed algorithm consistently enhances the visual quality of motion impaired cone beam computed tomography scans, thus eliminating the need for a re‐scan in certain cases, considerably lowering radiation dosage for the patient. It can flexibly be used with differently sized regions of interest and is even applicable to local tomography. [ABSTRACT FROM AUTHOR]

The recent discovery of HfO2-based and nitride-based ferroelectrics that are compatible to the semiconductor manufacturing process has revitalized the field of ferroelectric-based nanoelectronics. Guided by a simple design principle of charge compensation and density functional theory calculations, we discover that HfO2-like mixed-anion materials, TaON and NbON, can crystallize in the polar Pca 2 1 phase with a strong thermodynamic driving force to adopt anion ordering spontaneously. Both oxynitrides possess large remnant polarization, low switching barriers, and unconventional negative piezoelectric effect, making them promising piezoelectrics and ferroelectrics. Distinct from HfO2 that has a wide bandgap, both TaON and NbON can absorb visible light and have high charge carrier mobilities, suitable for ferroelectric photovoltaic and photocatalytic applications. This class of multifunctional nonperovskite oxynitride containing economical and environmentally benign elements offers a platform to design and optimize high-performing ferroelectric semiconductors for integrated systems. [ABSTRACT FROM AUTHOR]

Object reidentification (ReID) in cluttered rigid scenes is a challenging problem especially when same-looking objects coexist in the scene. ReID is accepted to be one of the most powerful tools for matching the correct identities to each individual object when issues such as occlusion, missed detections, multiple same-looking objects coexisting in the same scene, and disappearance of objects from the view and/or revisiting the same region arise. We propose a novel framework towards more efficient object ReID, improved object reidentification (IO-ReID), to perform object ReID in challenging scenes with real-time processing in mind. The proposed approach achieves distinctive and efficient object embedding via training with the triplet loss, with input from both the foreground/background split by bounding box, and the full input image. With extensive experiments on two datasets serving for Object ReID, we demonstrate that the proposed method, IO-ReID, obtains a higher ReID accuracy and runs faster compared to the state-of-the-art methods on object ReID. [ABSTRACT FROM AUTHOR]

Automated cell segmentation from optical microscopy images is usually the first step in the pipeline of single-cell analysis. Recently, deep-learning based algorithms have shown superior performances for the cell segmentation tasks. However, a disadvantage of deep-learning is the requirement for a large amount of fully annotated training data, which is costly to generate. Weakly-supervised and self-supervised learning is an active research area, but often the model accuracy is inversely correlated with the amount of annotation information provided. Here we focus on a specific subtype of weak annotations, which can be generated programmably from experimental data, thus allowing for more annotation information content without sacrificing the annotation speed. We designed a new model architecture for end-to-end training using such incomplete annotations. We have benchmarked our method on a variety of publicly available datasets, covering both fluorescence and bright-field imaging modality. We additionally tested our method on a microscopy dataset generated by us, using machine-generated annotations. The results demonstrated that our models trained under weak supervision can achieve segmentation accuracy competitive to, and in some cases, surpassing, state-of-the-art models trained under full supervision. Therefore, our method can be a practical alternative to the established full-supervision methods. A cell segmentation model is presented that is trained on weak annotations which can be generated programmably from experimental data, allowing for more annotation information content without sacrificing annotation speed. [ABSTRACT FROM AUTHOR]

This paper introduces a comprehensive study on vibration damping of a lumped aeroelastic wing model with translational linear and torsional nonlinear spring elements considering different actuation scenarios. The wing models have two degrees of freedom (DoFs) representing translational and torsional oscillations. On the other hand, the flap angles represent the control inputs that attempt to regulate the wing vibrations. Depending on the number of flaps designed, three actuation scenarios are investigated including fully actuated, overactuated, and underactuated wing models. For a fully actuated wing system (Scenario 1), conventional adaptive control strategies can be used for damping wing oscillations; however, adaptive approximation control is adopted in this work due to its capabilities for controlling (regulating) the dynamic system in the presence of the unknown system parameters. On the other hand, in the overactuated wing model (Scenario 2), the wing system has more control inputs than the DoFs and hence infinite solutions for the control input response are obtained. The Pseudoinverse matrix is a powerful tool to resolve this problem. In Scenario 3, the control inputs are less than the DoFs and hence a partial feedback linearization control strategy with an adaptive approximation compensator is used for regulation purposes; however, the internal dynamics of the underactuated wing system should be stable. Simulation experiments are performed to prove the effectiveness of control methods of the investigated scenarios. [ABSTRACT FROM AUTHOR]

Materials science and technology, with the advent of nanotechnology, has brought about innumerable nanomaterials and multi-functional materials, with intriguing yet profound properties, into the scientific realm. Even a minor functionalization of a nanomaterial brings about vast changes in its properties that could be potentially utilized in various applications, particularly for biological applications, as one of the primary needs at present is for point-of-care devices that can provide swifter, accurate, reliable, and reproducible results for the detection of various physiological conditions, or as elements that could increase the resolution of current bio-imaging procedures. In this regard, iron oxide nanoparticles, a major class of metal oxide nanoparticles, have been sweepingly synthesized, characterized, and studied for their essential properties; there are 14 polymorphs that have been reported so far in the literature. With such a background, this review's primary focus is the discussion of the different synthesis methods along with their structural, optical, magnetic, rheological and phase transformation properties. Subsequently, the review has been extrapolated to summarize the effective use of these nanoparticles as contrast agents in bio-imaging, therapeutic agents making use of its immune-toxicity and subsequent usage in hyperthermia for the treatment of cancer, electron transfer agents in copious electrochemical based enzymatic or non-enzymatic biosensors and bactericidal coatings over biomaterials to reduce the biofilm formation significantly. [ABSTRACT FROM AUTHOR]

This article is devoted to the landscape and urban planning system formation issues of the Moscow region, based on the integration of landscape and urban planning approaches. The current proposal considers the landscape both as a system and as an active part of the completely urban planning process. The article aims to present landscape and urban planning as systemic tools for transforming the spatial and planning structure of the macro-region - the Moscow region, offering opportunities for the physical and spatial restructuring of regional landscapes into a single green infrastructure of the region. The relevance of the study is related to the lack of documents in the Town Planning Code of Russia substantiating the need for the development of landscape planning projects, which are necessary for the landscape and urban planning system formation of cities, agglomerations, provinces, regions. In creating the landscape and urban planning system of the Moscow region, it is necessary to rely on the theory and practice of landscape urbanism, which shows the possibilities of its active use in the modern process of urban planning development. Furthermore, this article specifies modern research in the landscape and urban planning transformation field of spatial planning structures at the macro-regional level (macro-regional scale). The article will be useful for training researchers and specialists who could improve planning methodology and, consequently, existing landscape and urban planning practices. [ABSTRACT FROM AUTHOR]

Factory extraction from satellite images is a key step in urban factory planning, and plays a crucial role in ecological protection and land-use optimization. However, factory extraction is greatly underexplored in the existing literature due to the lack of large-scale benchmarks. In this paper, we contribute a challenging benchmark dataset named SFE4395, which consists of 4395 satellite images acquired from Google Earth. The features of SFE4395 include rich multiscale factory instances and a wide variety of factory types, with diverse challenges. To provide a strong baseline for this task, we propose a novel bidirectional feature aggregation and compensation network called BACNet. In particular, we design a bidirectional feature aggregation module to sufficiently integrate multiscale features in a bidirectional manner, which can improve the extraction ability for targets of different sizes. To recover the detailed information lost due to multiple instances of downsampling, we design a feature compensation module. The module adds the detailed information of low-level features to high-level features in a guidance of attention manner. In additional, a point-rendering module is introduced in BACNet to refine results. Experiments using SFE4395 and public datasets demonstrate the effectiveness of the proposed BACNet against state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The implementation of organic semiconductor (OSC) materials in X‐ray detectors provides exciting new opportunities for developing a new generation of biocompatible devices with high potential for the fabrication of sensitive and low‐cost X‐ray imaging systems. Here, the fabrication of high performance organic field‐effect transistors (OFETs) based on blends of 1,4,8,11‐tetramethyl‐6,13‐triethylsilylethynyl pentacene (TMTES) with polystyrene is reported. The films are printed employing a low cost and high‐throughput deposition technique. The devices exhibit excellent electrical characteristics with a high mobility and low density of hole traps, which is ascribed to the favorable herringbone packing (different from most pentacene derivatives) and the vertical phase separation in the blend films. As a consequence, an exceptional high sensitivity of (4.10 ± 0.05) × 1010 µC Gy–1cm–3 for X‐ray detection is achieved, which is the highest reported so far for a direct X‐ray detector based on a tissue equivalent full organic active layer, and is higher than most perovskite film‐based X‐ray detectors. As a proof of concept to demonstrate the high potential of these devices, an X‐ray image with sub‐millimeter pixel size is recorded employing a 4‐pixel array. This work highlights the potential exploitation of high performance OFETs for future innovative large‐area and highly sensitive X‐ray detectors for medical dosimetry and diagnostic applications. [ABSTRACT FROM AUTHOR]

A porous ceramic catalytic converter was synthesized on the basis of a coarse α-Al2O3 powder filler using ultrafine strengthening binders of the MgO + SiC + SiO2 composition and catalytically active Re2O7 and WO3 components (up to 4 wt %). Double-sided compression of the starting mixture under a pressure from 70 to 90 MPa followed by sintering of the samples at temperatures from 1200 to 1400°C was applied. The synthesized ceramic catalytic converters possessed an open porosity of about 40% and a pore size of 0.5 to 1.5 μm. The styrene selectivity of about 30% and the productivity up to 30 g h–1 dm–3 in the temperature range from 600 to 700°С were experimentally achieved. The degree of catalyst carbonization within the experimental time (6 h) did not exceed 0.31 wt %. The scientific principles of a one-step technology for the synthesis of a porous ceramic with simultaneous imparting of catalytic properties thereto were developed. The obtained ceramic catalytic converters of the [Re,W]/α-Al2O3 composition can produce styrene with a high efficiency in a wide temperature range. [ABSTRACT FROM AUTHOR]

For organic thin‐film transistors (OTFTs) made of solution processed stacks of organic semiconductor and dielectric materials, it is a grand challenge to eliminate the leakage current paths. With a top‐gate bottom‐contact structure, this work introduces a strong dipole interfacial layer made of self‐assembled monolayer (SAM) molecules at metal‐semiconductor contacts to suppress minority carrier injection for low leakage and stable operation, while not affecting majority carrier injection. Both gate insulator (GI) leakage and parasitic leakage in the device architecture are also effectively suppressed with a sputtering‐resistant polymer GI layer and photolith patterned OSC islands, respectively. The devices present a decent mobility with a typical value of 1.98 cm2 V–1 s–1, record‐low leakage current at 10–18 A µm−1 and large ON/OFF ratio (>1010) in a wide gate voltage range (100 V), reaching the theoretical limit and also the best level of inorganic counterparts despite much lower processing temperature (120 °C). Manufacturability of the material stack is verified on a 200 mm × 200 mm substrate and the fabricated 4.7 in. active‐matrix organic light‐emitting diode display, integrating more than 150 000 OTFTs, can be operated at ultra‐low frame‐rate (0.1 Hz) for power saving. [ABSTRACT FROM AUTHOR]

In recent years, topological insulators have drawn growing interest as a unique electronic state of matter toward quantum information technology. Despite the logic devices with magnetization switching through spin–orbit torque or the topological magneto-electric effect, realizing memory devices based on topological insulators has been urged in quantum computing applications. In this work, we report the design and fabrication of a non-volatile memory device that employs polarization of Bi2Se3 thin films achieving fast memory speed, sufficient memory window, and good reliability. The Bi2Se3 film polarizes under an external electrical field with charges accumulated on the top and bottom surfaces separating the electrons and holes. Such polarization is much faster than the carrier tunneling in conventional floating-gate flash memory and ferroelectric-based memory devices. In addition, good memory retention and endurance properties have also been obtained, showing great potential in high-performance memory application in future topological insulator-involved information technology. [ABSTRACT FROM AUTHOR]

Self‐assembled monolayers (SAMs) have been widely employed as an effective way to modify interfaces of electronic/optoelectronic devices. To achieve a good control of the growth and molecular functionality of SAMs, we develop a co‐assembled monolayer (co‐SAM) for obtaining efficient hole selection and suppressed recombination at the hole‐selective interface in inverted perovskite solar cells (PSCs). By engineering the position of methoxy substituents, an aligned energy level and favorable dipole moment can be obtained in our newly synthesized SAM, ((2,7‐dimethoxy‐9H‐carbazol‐9‐yl) methyl) phosphonic acid (DC‐PA). An alkyl ammonium containing SAM is co‐assembled to further optimize the surface functionalization and interaction with perovskite layer on top. A champion device with an excellent power conversion efficiency (PCE) of 23.59 % and improved device stability are achieved. This work demonstrates the advantage of using co‐SAM in improving performance and stability of PSCs. [ABSTRACT FROM AUTHOR]

In most deep learning-based brain tumor segmentation methods, training the deep network requires annotated tumor areas. However, accurate tumor annotation puts high demands on medical personnel. The aim of this study is to train a deep network for segmentation by using ellipse box areas surrounding the tumors. In the proposed method, the deep network is trained by using a large number of unannotated tumor images with foreground (FG) and background (BG) ellipse box areas surrounding the tumor and background, and a small number of patients (<20) with annotated tumors. The training is conducted by initial training on two ellipse boxes on unannotated MRIs, followed by refined training on a small number of annotated MRIs. We use a multi-stream U-Net for conducting our experiments, which is an extension of the conventional U-Net. This enables the use of complementary information from multi-modality (e.g., T1, T1ce, T2, and FLAIR) MRIs. To test the feasibility of the proposed approach, experiments and evaluation were conducted on two datasets for glioma segmentation. Segmentation performance on the test sets is then compared with those used on the same network but trained entirely by annotated MRIs. Our experiments show that the proposed method has obtained good tumor segmentation results on the test sets, wherein the dice score on tumor areas is (0.8407, 0.9104), and segmentation accuracy on tumor areas is (83.88%, 88.47%) for the MICCAI BraTS'17 and US datasets, respectively. Comparing the segmented results by using the network trained by all annotated tumors, the drop in the segmentation performance from the proposed approach is (0.0594, 0.0159) in the dice score, and (8.78%, 2.61%) in segmented tumor accuracy for MICCAI and US test sets, which is relatively small. Our case studies have demonstrated that training the network for segmentation by using ellipse box areas in place of all annotated tumors is feasible, and can be considered as an alternative, which is a trade-off between saving medical experts' time annotating tumors and a small drop in segmentation performance. [ABSTRACT FROM AUTHOR]

Providing strong carbon-metal (C–M) bonds, N-heterocyclic carbenes (NHCs) recently were introduced as surface modifiers for various applications. Here we report a fluorinated NHC (F-NHC) monolayer chemically bonded to Au with high thermal stability up to 200 °C. The effect of F-NHC modification on contact resistance in organic field-effect transistors (OFETs) was further investigated. In comparison to devices without F-NHC modification, transistors with the F-NHC modified gold electrodes show a significant improvement in carrier mobility in the saturation region owing to the reduced contact resistance (Rc). Density Functional Theory (DFT) calculations indicate that, when bonding to Au, the F-NHC molecule transfers 0.40 e to Au and creates a doping interface between Au and p-type organic semiconductors. The charge transfer between the F-NHC and Au leads to a generation of holes at the F-NHC/organic semiconductor interface, which may cause an efficient carrier tunneling for contact resistance improvement. The work lays the foundation for the future applications of carbenes in organic electronics. [ABSTRACT FROM AUTHOR]

This paper analyzes the distribution of Heracleum persicum, H. mantegazzianum, and H. sosnowskyi at the northern limit of their secondary ranges in Europe based on original and published data. The northernmost H. persicum occurrences are localized in coastal regions in the northern and central parts of the Scandinavian Peninsula (up to 71° N). In Fennoscandia, H. mantegazzianum and H. sosnowskyi were noted up to 69° N. The gradient of climatic resources in the subarctic and temperate zones made it possible to identify factors limiting further expansion of these species in northern Europe and determine their tolerance limits to these factors. The duration of the frostless season at the northern boundary of the secondary range of invasive Heracleum species is 80–150 days. The probability of cold damage to vegetating plants in areas located north of 66° N (i.e., in the northern part of Finland and in the continental northern part of European Russia) is high. The biological minimum for the sum of active air temperatures ≥5°C is 1150°C, while the minimum requirement of the studied plants for the sum of active temperatures ≥10°C is over 450°C. If available thermal resources exceed this level, then invasive Heracleum species can naturalize in climatic conditions of subarctic Europe. The presence of a sustainable snow cover more than 25 cm depth in areas where the minimum winter temperatures are less than –30°C prevents the freezing of renewal buds and seedlings, thus, preserving the viability of plants. It is proposed to use climatic indices computed as ratios between the air temperature and the snow cover depth (or the precipitation amount in winter) as climatic markers characterizing wintering conditions for plants. The main factors limiting the spread and naturalization of invasive Heracleum species in northern Europe are lack of heat, soil freezing to temperatures critical for hibernating plant organs, and early autumn frosts. [ABSTRACT FROM AUTHOR]

The total boll count from a plant is one of the most important phenotypic traits for cotton breeding and is also an important factor for growers to estimate the final yield. With the recent advances in deep learning, many supervised learning approaches have been implemented to perform phenotypic trait measurement from images for various crops, but few studies have been conducted to count cotton bolls from field images. Supervised learning models require a vast number of annotated images for training, which has become a bottleneck for machine learning model development. The goal of this study is to develop both fully supervised and weakly supervised deep learning models to segment and count cotton bolls from proximal imagery. A total of 290 RGB images of cotton plants from both potted (indoor and outdoor) and in-field settings were taken by consumer-grade cameras and the raw images were divided into 4350 image tiles for further model training and testing. Two supervised models (Mask R-CNN and S-Count) and two weakly supervised approaches (WS-Count and CountSeg) were compared in terms of boll count accuracy and annotation costs. The results revealed that the weakly supervised counting approaches performed well with RMSE values of 1.826 and 1.284 for WS-Count and CountSeg, respectively, whereas the fully supervised models achieve RMSE values of 1.181 and 1.175 for S-Count and Mask R-CNN, respectively, when the number of bolls in an image patch is less than 10. In terms of data annotation costs, the weakly supervised approaches were at least 10 times more cost efficient than the supervised approach for boll counting. In the future, the deep learning models developed in this study can be extended to other plant organs, such as main stalks, nodes, and primary and secondary branches. Both the supervised and weakly supervised deep learning models for boll counting with low-cost RGB images can be used by cotton breeders, physiologists, and growers alike to improve crop breeding and yield estimation. [ABSTRACT FROM AUTHOR]

The recent realization of topology as a mathematical concept in condensed matter systems has shattered Landau's widely accepted classification of phases by spontaneous symmetry breaking as he famously said, "a particular symmetry property exists or does not exist." Topological materials (TMs) such as topological insulators and topological semimetals, are characterized by properties that depend on the topology of the band structure. Such dependence has drastic implications on the optical, electrical, and thermal properties of the material. Fundamental physics of TMs is currently under active research in condensed matter, materials science, and high energy physics. In this review, recent advances in exploiting the unique properties of TMs to realize functional optoelectronic devices are surveyed. Current and future applications that are, or may be, enabled by their unique properties are discussed. Although many theoretical ideas have been proposed over the past decade or so on using TMs in optoelectronic applications, the focus will be on experimentally realized devices. [ABSTRACT FROM AUTHOR]

Probing the surface states in Bi2Se3 via electronic transport measurements is difficult due to the significantly larger numbers of bulk carriers. Herein, we report the contribution of both bulk and surface states on the measured photocurrent at room temperature and the electrical transport measurements at low temperatures in an epitaxial thin film of intrinsic Bi2Se3 capped with a high K dielectric, Al2O3. The measured photocurrent continuously increases when the gate voltage is swept toward the negative side from 10 to −10 V, indicating the movement of the Fermi level below the conduction band edge. Moreover, the contribution of the surface state conduction increases when the Fermi level moves inside the bandgap toward the Dirac point. Furthermore, the measured Seebeck coefficient (S) continuously increases with sweeping gate voltage from 10 to −10 V. Similar correlations of the photocurrent and S value with the gate voltage illustrate the contribution of the photothermoelectric effect due to the conduction of both bulk and surface states. Additionally, the ambipolar charge transport was observed in the electrical measurement at 32 K for the four-probe configuration. The ambipolar charge transport is possibly indicative of surface state transport. [ABSTRACT FROM AUTHOR]

Organic molecular semiconductors have been paid great attention due to their advantages of low-temperature processability, low fabrication cost, good flexibility, and excellent electronic properties. As a typical example of five-ring-fused organic semiconductors, a single crystal of pentacene shows a high mobility of up to 40 cm2 V−1 s−1, indicating its potential application in organic electronics. However, the photo- and optical instabilities of pentacene make it unsuitable for commercial applications. But, molecular engineering, for both the five-ring-fused building block and side chains, has been performed to improve the stability of materials as well as maintain high mobility. Here, several groups (thiophenes, pyrroles, furans, etc.) are introduced to design and replace one or more benzene rings of pentacene and construct novel five-ring-fused organic semiconductors. In this review article, ∼500 five-ring-fused organic prototype molecules and their derivatives are summarized to provide a general understanding of this catalogue material for application in organic field-effect transistors. The results indicate that many five-ring-fused organic semiconductors can achieve high mobilities of more than 1 cm2 V−1 s−1, and a hole mobility of up to 18.9 cm2 V−1 s−1 can be obtained, while an electron mobility of 27.8 cm2 V−1 s−1 can be achieved in five-ring-fused organic semiconductors. The HOMO–LUMO levels, the synthesis process, the molecular packing, and the side-chain engineering of five-ring-fused organic semiconductors are analyzed. The current problems, conclusions, and perspectives are also provided. [ABSTRACT FROM AUTHOR]

A single‐crystal Bi2Se3 topological insulator is fabricated using the Bridgman–Stockbarger method. The crystal structure and atomic lattice parameters are identified by X‐ray diffraction analysis. The nanoindentation size effect on creep displacement, activation volume, and strain rate sensitivity (SRS) with different maximum holding loads between 1000 and 5000 μN is investigated using depth‐sensing nanoindentation. Furthermore, the effect of the loading rate on the steady‐state creep displacement and SRS is analyzed and discussed. Results show Bi2Se3's low resistance to plastic deformation and a significant increase of creep displacement with increasing holding load and holding rate. Additionally, creep strain rate, activation volume, and SRS are also calculated from the secondary stage creep, and results are compared with those of other flexible electronic materials. [ABSTRACT FROM AUTHOR]

Organic phototransistors (OPTs) are playing an indispensable role in organic optoelectronics, which greatly show their promising application in optical communication, video imaging, missile guidance, and night vision. However, because the thermally activated mode dominated for thin‐film devices leads to a sharp drop in mobility at low temperatures, until now, most of the studies about OPTs are performed at room temperature, severely hindering their further potential optoelectronic application over a broad range of temperatures, especially at low temperature environment. In this work, the optoelectronic properties of a small molecule (2,6‐diphenylanthracene, DPA) based OPTs with band‐like transport are studied at low temperatures. The devices exhibit outstanding optoelectronic properties in terms of mobility (2.6 cm2 V−1 s−1), on/off ratio (≈104), detectivity (1013 Jones), and external quantum efficiency (2500%) even at 150 K, which is superior to the performance of devices with thermally activated mode. In addition, the organic photodetector at low temperatures is also fabricated. Our results demonstrate that organic π‐conjugated DPA small‐molecule has great potential in low‐temperature application. [ABSTRACT FROM AUTHOR]

Two solution‐processable organic semiconductors, DFPT‐DTTR (1) and DFPbT‐DTTR (2), composed of pentafluorophenyl (FP) end‐capped 3,5‐dialkyl dithienothiophene (DTTR) core with thiophene (T) or bithiophene (bT) as π‐bridged spacers are developed and investigated for their optical, electrochemical, microstructural, and electrical properties. With more conjugated bithiophene units, compound 2 exhibits a red‐shifted UV–vis absorption band and upshifted HOMO/downshifted LUMO energy levels. According to the density functional theory, compound 2 features a more twisted molecular structure due to the intrinsic non‐coplanar blocks in the π‐backbones. Compound 1‐based organic field effect transistors exhibit efficient hole transport with mobility up to 0.48 cm2 V−1 s−1. This is one of the high mobility organic semiconductors exhibiting p‐channel characteristics based on solution‐processable small molecular FP end‐capped fused/oligothiophenes. With large and interconnected crystalline morphologies, decreased π–π stacking distance, and less steric hindrance, compound 1 exhibits two orders of magnitude higher mobility than the more distorted 2, which exhibits lower hole mobility of 1.82 × 10−3 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

A porous, catalytically active converter was synthesized based on coarse SiC. For the synthesis of the converter, ultrafine additives of the eutectic composition MgO and SiC were introduced into the original SiC powder. The resulting mixture was pressed at the maximum pressure from 75 to 125 MPa, followed by sintering in the range from 1200 to 1450°C. The open porosity of the converters was ~40%, the size of the pores ranged from 4 to 6 μm. At 600°C, ethylbenzene conversion was ~73%, styrene yield ~9%, selectivity of styrene ~12.3%. The degree of carbonization of the catalyst after 2.5 h did not exceed ~0.003 wt.%, which is an ultra-low indicator that radically increases the life of a catalytic converter without the need for regeneration or replacement. [ABSTRACT FROM AUTHOR]

Caucasian hogweeds, mainly the Sosnowsky's hogweed Heracleum sosnowskyi and the giant hogweed Heracleum mantegazzianum, create one of the most problematic plant invasions in the world. Due to their large size (weeds reaching 4–5 meters in height), they seem to be herbaceous plants that can threaten birds living in forest stands. This research quantified the structure and diversity of the forest birds' community in forests with varying areas of invasive hogweeds located in south-eastern Poland. Changes in the accompanying non-forest birds' community were also assessed. The study addressed the following questions: 1. How does the invaded area correlate with the abundance of forest birds? 2. How do communities and species respond to invaded vegetation? 3. How do the invading plants affect the various types of diversity of forest and non-forest birds? It turned out that both surveyed bird communities had a lower alpha diversity in invaded sites. Only forest birds, not able to change their location easily, formed a unique community (i.e., had a higher beta diversity) near invaders. Forest birds showed unchanged functional diversity based on the relative bird abundance and their connection, or lack of it, with the forest development phases. The effect of hogweeds on the abundance of forest birds was more negative in severely invaded areas with anthropogenic habitats. Non-forest birds showed higher species loss near the invasion, constant beta diversity and decreased functional diversity. This study is important as the forest is a climax community in the temperate zone, and unused open areas become spontaneously overgrown with young forests. Weeds disseminating after crop abandonment can highly and commonly affect forest and non-forest bird communities co-occurring in this type of overgrowing area. [ABSTRACT FROM AUTHOR]

Caucasian hogweeds are plants introduced to Europe from the Caucasus area. This review concerns the two most common ones—the giant hogweed Heracleum mantegazzianum and the Sosnowsky's hogweed Heracleum sosnowskyi. The first of them was imported as garden decorations from the 19th century, mainly to Western Europe, while the second one was introduced from the mid–20th century to agricultural areas in Eastern Europe. Nowadays, these two species create one of the most problematic invasions in the world. This review aimed to synthesize research on those invaders based on 277 articles selected from the "Scopus" database. Most of the articles concerned their extensive distribution, at least on a continental scale and the rapid dispersal. The reviewed research showed that the complex physicochemical properties of hogweeds tissues and secretions significantly affected insects, aphids, ants, nematodes, fungi, soil microorganisms, plant communities, birds, and many other components of the ecosystems. This knowledge turned out to be disproportionately small to the scale of the problem. The review also showed what ecological traits of hogweeds were responsible for their wide and various role in the environment. Thus far, no effective method to eradicate Caucasian hogweeds has been found. This could be a growing mistake, given that they are probably during the rapid evolutionary changes within the range of their invasion. [ABSTRACT FROM AUTHOR]