A highly modular synthesis of BNB- and BOB-doped phenalenyls is presented. Treatment of the 1,8-naphthalenediyl-bridged boronic acid anhydride 1 with LiAlH4/Me3SiCl afforded the corresponding 1,8-naphthalenediyl-supported diborane(6) 2, which served as the starting material for all subsequent transformations. Upon addition of MesMgBr/Me3SiCl, 2 was readily converted to the tetraorganyl diborane(6) 5. The further heteroatoms were finally introduced through the reaction of 2 with (Me3Si)2NR′ or 5 with H2NR′ or H2O (R′ = H, Me, p-Tol). A helically twisted, fully BNB-embedded PAH 11 was prepared by combining 2 with a dibrominated m-terphenylamine, followed by a Grignard-mediated double ring-closure reaction. All compounds devoid of B–H bonds show favorable optoelectronic properties, such as luminescence and reversible reduction behavior. In the case of the BNB-phenalenyl 7 (BMes, NMe), the radical-anion salt K­[7 •] was generated through chemical reduction with K metal and characterized by EPR spectroscopy. K­[7 •] is not long-term stable in a THF/c-hexane solution, but abstracts an H atom with formation of the diamagnetic BNB-doped 1H-phenalene K­[7H].

This paper reviews the concepts, status and challenges for the DRAM scaling down to 40nm. The technologies that are discussed are the DRAM cell capacitor structures and materials, as well as the cell transistor structures.

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The eruption of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (corona virus disease, COVID-19) in Wuhan, China, and its global spread has led to an exponentially growing number of infected patients, currently exceeding over 6.6 million and over 390,000 deaths as of the 5th of June 2020. In this pandemic situation, health systems have been put under stress, and the demand for personal protective equipment (PPE) exceeded the delivery capabilities of suppliers. To address this issue, 3D printing was identified as a possible solution to quickly produce PPE items such as face shields, mask straps, masks, valves, and ear savers. Around the world, companies, universities, research institutions, and private individuals/hobbyists stepped into the void, using their 3D printers to support hospitals, doctors, nursing homes, and even refugee camps by providing them with PPE. In Germany, the makervsvirus movement took up the challenge and connected thousands of end users, makers, companies, and logistic providers for the production and supply of face shields, protective masks, and ear savers. The Karlsruhe Institute of Technology (KIT) also joined the makervsvirus movement and used its facilities to print headbands for face shield assemblies and ear savers. Within this paper, the challenges and lessons learned from the quick ramp up of a research laboratory to a production site for medium-sized batches of PPE, the limitations in material supply, selection criteria for suitable models, quality measures, and future prospects are reported and conclusions drawn.

Modern society is striving for digital connectivity that demands information security. As an emerging technology, printed electronics is a key enabler for novel device types with free form factors, customizability, and the potential for large-area fabrication while being seamlessly integrated into our everyday environment. At present, information security is mainly based on software algorithms that use pseudo random numbers. In this regard, hardware-intrinsic security primitives, such as physical unclonable functions, are very promising to provide inherent security features comparable to biometrical data. Device-specific, random intrinsic variations are exploited to generate unique secure identifiers. Here, we introduce a hybrid physical unclonable function, combining silicon and printed electronics technologies, based on metal oxide thin film devices. Our system exploits the inherent randomness of printed materials due to surface roughness, film morphology and the resulting electrical characteristics. The security primitive provides high intrinsic variation, is non-volatile, scalable and exhibits nearly ideal uniqueness.

The last decade of direct imaging (DI) searches for sub-stellar companions has uncovered a widely diverse sample that challenges the current formation models, while highlighting the intrinsically low occurrence rate of wide companions, especially at the lower end of the mass distribution. These results clearly show how blind surveys, crucial to constrain the underlying planet and sub-stellar companion population, are not an efficient way to increase the sample of DI companions. It is therefore becoming clear that efficient target selection methods are essential to ensure a larger number of detections. We present the results of the COPAINS Survey conducted with SPHERE/VLT, searching for sub-stellar companions to stars showing significant proper motion differences (Δμ) between different astrometric catalogues. We observed twenty-five stars and detected ten companions, including four new brown dwarfs: HIP 21152 B, HIP 29724 B, HD 60584 B and HIP 63734 B. Our results clearly demonstrates how astrometric signatures, in the past only giving access to stellar companions, can now thanks to Gaia reveal companions well in the sub-stellar regime. We also introduce FORECAST (Finley Optimised REtrieval of Companions of Accelerating STars), a tool which allows to check the agreement between position and mass of the detected companions with the measured Δμ. Given the agreement between the values of the masses of the new sub-stellar companions from the photometry with the model-independent ones obtained with FORECAST, the results of COPAINS represent a significant increase of the number of potential benchmarks for brown dwarf and planet formation and evolution theories.

Transmission electron cryo-microscopy (cryo­EM) of vitrified biological specimens is a powerful tool for structural biology. Current preparation of vitrified biological samples starts off with sample isolation and purification, followed by the fixation in a freestanding layer of amorphous ice. Here, we demonstrate that ultrathin (∼10 nm) smart molecular nanosheets having specific biorecognition sites embedded in a biorepulsive layer covalently bound to a mechanically stable carbon nanomembrane allow for a much simpler isolation and structural analysis. We characterize in detail the engineering of these nanosheets and their biorecognition properties employing complementary methods such as X-ray photoelectron and infrared spectroscopy, atomic force microscopy as well as surface plasmon resonance measurements. The desired functionality of the developed nanosheets is demonstrated by in situ selection of a His-tagged protein from a mixture and its subsequent structural analysis by cryoEM.

Several therapeutic methods have been employed in the management of localized granuloma annulare (GA), with varying degrees of success. We performed a prospective trial to evaluate the efficacy, cosmetic results, and safety of cryosurgical treatment in GA. Thirty-one patients with localized GA were treated by cryosurgery, using the contact method. Nitrous oxide (-86 degrees C) or liquid nitrogen (-196 degrees C) were used as refrigerants, and were applied with closed probes; each lesion was treated with one freeze-thaw cycle of 10-60 s per session. If necessary, treatment was repeated after 20-30 days. Resolution of the lesions was obtained in all patients, and in 25 of 31 patients (80.6%) they resolved after a single freeze-thaw cycle. Relapse occurred in only one of 11 patients who were followed for more than 2 years, and this occurred 16 months after treatment. Excellent cosmetic results were obtained in 14 of 28 patients who were eligible for evaluation (50%), and good results in 11 (39.3%). The cosmetic result obtained by cryosurgery with nitrous oxide was independent of the size of the lesion, whereas in the group of patients treated with liquid nitrogen a better cosmetic result was obtained with smaller lesions (comparison of lesions < or = 2.40 cm2 with those > 2.40 cm2; P = 0.04). The duration of the lesion, its location, previous treatment with another method, and the number of treatment sessions, did not have any influence on the cosmetic result. The treatment was generally well tolerated. Blister formation occurred in all patients.(ABSTRACT TRUNCATED AT 250 WORDS)