Orientation-dependent ionization energies and interface dipoles in ordered molecular assemblies

Although an isolated individual molecule clearly has only one ionization potential, multiple values are found for molecules in ordered assemblies. Photoelectron spectroscopy of archetypical pi-conjugated organic compounds on metal substrates combined with first-principles calculations and electrostatic modelling reveal the existence of a surface dipole built into molecular layers. Conceptually different from the surface dipole at metal surfaces, its origin lies in details of the molecular electronic structure and its magnitude depends on the orientation of molecules relative to the surface of an ordered assembly. Suitable pre-patterning of substrates to induce specific molecular orientations in subsequently grown films thus permits adjusting the ionization potential of one molecular species over up to 0.6 eV via control over monolayer morphology. In addition to providing in-depth understanding of this phenomenon, our study offers design guidelines for improved organic-organic heterojunctions, hole- or electron-blocking layers and reduced barriers for charge-carrier injection in organic electronic devices.     

Isolation and identification of residual chromophores in cellulosic materials

A general procedure was developed for the isolation of residual chromophores in or on cellulosic material, which were hitherto inaccessible to structure elucidation due to their extremely low content in the ppb concentration scale. It is applicable to cellulosic pulp, cellulosic fibers (viscose, Lyocell) and cellulose derivatives (acetate, carbonyl-labeled cellulose) as well. The chromophore identification comprises treatment of the cellulosic material with boron trifluoride-acetic acid complex (BF₃·2HOAc) containing sulfite, chromatographic separation of the resulting chromophore-containing mixture, and structure determination of the main constituents by NMR/MS and comparison to authentic samples. Both adsorbed and covalently bound aromatic and quinoid compounds are selectively released by the treatment. Covalent ester, ether and secondary alkyl links between chromophore and cellulose are broken.Four cellulosic example substrates have been analyzed for their chromophore content: Lyocell fibers, cellulose triacetate, pulp after thermal treatment in N,N-dimethylacetamide, and pulp containing carbonyl-selective labels, and up to 11 chromophores per sample have been identified.     

Clinical Phenotype of PDE6B-Associated Retinitis Pigmentosa

In this retrospective, longitudinal, observational cohort study, we investigated the phenotypic and genotypic features of retinitis pigmentosa associated with variants in the PDE6B gene. Patients underwent clinical examination and genetic testing at a single tertiary referral center, including best-corrected visual acuity (BCVA), kinetic visual field (VF), full-field electroretinography, full-field stimulus threshold, spectral domain optical coherence tomography, and fundus autofluorescence imaging. The genetic testing comprised candidate gene sequencing, inherited retinal disease gene panel sequencing, whole-genome sequencing, and testing for familial variants by Sanger sequencing. Twenty-four patients with mutations in PDE6B from 21 families were included in the study (mean age at the first visit: 32.1 ± 13.5 years). The majority of variants were putative splicing defects (8/23) and missense (7/23) mutations. Seventy-nine percent (38/48) of eyes had no visual acuity impairment at the first visit. Visual acuity impairment was mild in 4% (2/48), moderate in 13% (6/48), and severe in 4% (2/48). BCVA was symmetrical in the right and left eyes. The kinetic VF measurements were highly symmetrical in the right and left eyes, as was the horizontal ellipsoid zone (EZ) width. Regarding the genetic findings, 43% of the PDE6B variants found in our patients were novel. Thus, this study contributed substantially to the PDE6B mutation spectrum. The visual acuity impairment was mild in 83% of eyes, providing a window of opportunity for investigational new drugs. The EZ width was reduced in all patients and was highly symmetric between the eyes, making it a promising outcome measure. We expect these findings to have implications on the design of future PDE6B-related retinitis pigmentosa (RP) clinical trials.     

Structure Evolution in Polyethylene-Derived Carbon Fiber Using a Combined Electron Beam-Stabilization-Sulphurization Approach

A new approach is described for the production of poly(ethylene) (PE) derived carbon fibers (CFs) that entails the melt spinning of PE fibers from a suitable precursor, their cross-linking by electron beam (EB) treatment, and sulphurization with elemental sulphur (S₈), followed by pyrolysis and carbonization. Instead of focusing on mechanical properties, analysis of CF structure formation during all process steps is carried out by different techniques comprising solid-state nuclear magnetic resonance spectroscopy, thermogravimetric analysis coupled to mass spectrometry/infrared spectroscopy, elemental analysis, energy dispersive X-ray scattering, scanning electron microscopy, Raman spectroscopy, and wide-angle X-ray diffraction. A key step in structure formation is the conversion of PE into poly(thienothiophene)s during sulphurization; these species are stabile under inert gas up to 700 °C as confirmed by Raman analysis. Above this temperature, they condense into poly(napthathienophene)s, which are then converted into graphite-type structures during pyrolysis.     

A MXene‐Based Wearable Biosensor System for High‐Performance In Vitro Perspiration Analysis

Wearable electrochemical biosensors for sweat analysis present a promising means for noninvasive biomarker monitoring. However, sweat‐based sensing still poses several challenges, including easy degradation of enzymes and biomaterials with repeated testing, limited detection range and sensitivity of enzyme‐based biosensors caused by oxygen deficiency in sweat, and poor shelf life of sensors using all‐in‐one working electrodes patterned by traditional techniques (e.g., electrodeposition and screen printing). Herein, a stretchable, wearable, and modular multifunctional biosensor is developed, incorporating a novel MXene/Prussian blue (Ti₃C₂T_x/PB) composite designed for durable and sensitive detection of biomarkers (e.g., glucose and lactate) in sweat. A unique modular design enables a simple exchange of the specific sensing electrode to target the desired analytes. Furthermore, an implemented solid–liquid–air three‐phase interface design leads to superior sensor performance and stability. Typical electrochemical sensitivities of 35.3 µA mm ^?1 cm^?2 for glucose and 11.4 µA mm ^?1 cm^?2 for lactate are achieved using artificial sweat. During in vitro perspiration monitoring of human subjects, the physiochemistry signals (glucose and lactate level) can be measured simultaneously with high sensitivity and good repeatability. This approach represents an important step toward the realization of ultrasensitive enzymatic wearable biosensors for personalized health monitoring.     

Participants’ personal note-taking in meetings and its value for automatic meeting summarisation

This paper reports the results of novel quantitative research on multiple people’s personal note-taking in meetings with the long-term aim of aiding the creation of innovative meeting understanding applications. We present three experiments using a large number of group meetings taken from the Augmented Multi-party Interaction meeting corpus. Statistical techniques were employed for this work. Our findings suggest that temporal note-taking overlap information and the semantic content of the written private notes taken by many meeting participants both point to the majority of the most informative meeting events. Thus, the characteristics of note-taking can be seen as a contributing feature for new automatic meeting summarisation approaches and for the development of future meeting browser environments that better support the needs of individuals and organisations.     

The Proteome Profiles of the Cerebellum of Juvenile,Adult and Aged Rats—An Ontogenetic Study

In this study, we searched for proteins that change their expression in the cerebellum (Ce) of rats during ontogenesis. This study focuses on the question of whether specific proteins exist which are differentially expressed with regard to postnatal stages of development. A better characterization of the microenvironment and its development may result from these study findings. A differential two-dimensional polyacrylamide gel electrophoresis (2DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis of the samples revealed that the number of proteins of the functional classes differed depending on the developmental stages. Especially members of the functional classes of biosynthesis, regulatory proteins, chaperones and structural proteins show the highest differential expression within the analyzed stages of development. Therefore, members of these functional protein groups seem to be involved in the development and differentiation of the Ce within the analyzed development stages. In this study, changes in the expression of proteins in the Ce at different postnatal developmental stages (postnatal days (P) 7, 90, and 637) could be observed. At the same time, an identification of proteins which are involved in cell migration and differentiation was possible. Especially proteins involved in processes of the biosynthesis and regulation, the dynamic organization of the cytoskeleton as well as chaperones showed a high amount of differentially expressed proteins between the analyzed dates.     

Superporous Poly(ethylene glycol) Diacrylate Cryogel with a Defined Elastic Modulus for Prostate Cancer Cell Research

The physical and mechanical properties of the tumor microenvironment are crucial for the growth, differentiation and migration of cancer cells. However, such microenvironment is not found in the geometric constraints of 2D cell culture systems used in many cancer studies. Prostate cancer research, in particular, suffers from the lack of suitable in vitro models. Here a 3D superporous scaffold is described with thick pore walls in a mechanically stable and robust architecture to support prostate tumor growth. This scaffold is generated from the cryogelation of poly(ethylene glycol) diacrylate to produce a defined elastic modulus for prostate tumor growth. Lymph node carcinoma of the prostate (LNCaP) cells show a linear growth over 21 d as multicellular tumor spheroids in such a scaffold with points of attachments to the walls of the scaffold. These LNCaP cells respond to the growth promoting effects of androgens and demonstrate a characteristic cytoplasmic‐nuclear translocation of the androgen receptor and androgen‐dependent gene expression. Compared to 2D cell culture, the expression or androgen response of prostate cancer specific genes is greatly enhanced in the LNCaP cells in this system. This scaffold is therefore a powerful tool for prostate cancer studies with unique advantages over 2D cell culture systems.     

Plasma-printing and galvanic metallization hand in hand—A new technology for the cost-efficient manufacture of flexible printed circuits

A new potentially cost-efficient technology combining patterned atmospheric pressure dielectric barrier discharge (DBD) treatment, here referred to as «plasma-printing», and galvanic plating for the production of flexible printed circuits (FPC) is presented in this contribution. The technology is being jointly developed by partners from industry and academia, a major aim being the realization of the processes in a reel-to-reel production system. So far, plasma-printing experiments have been carried out using lab-scale batch plants. Using suitable plasma conditions and electroless plating baths, RFID-like tag and interdigital structures with line widths and spaces down to 100 μm could already be produced. Adhesion of copper on DBD treated polyimide foil reached up to about 1 N/mm, as was determined in a peel test similar to that described in the DIN 53494.