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The snow physical parameters are closely related to the sizes, shapes, and chemical composition of light‐absorbing particles (LAPs). By utilizing a computer‐controlled scanning electron microscope software called IntelliSEM‐EPASTM, we first report the measured size‐resolved concentration of soot, dust, and fly ash particles in fresh (wet) and aged (dry deposition) snow samples collected at an industrial city in China during and after a snowfall at intervals of 6–8 days. Due to wet scavenging by seasonal snow, soot and dust particles in snow are absorbed by 69.7% and 30.3% at wavelengths of 550 nm, lowering snow albedo by 0.0089 and 0.0039, respectively. Soot particle size increases slightly during dry deposition, whereas size‐resolved mineral dust does not undergo a significant shift in particle size. These results indicate the essentiality to involve the effects of accurate size and composition of in‐snow LAPs for a better assessment of snow light absorption and reflectance. Plain Language Summary: A field survey was undertaken to collect freshly fallen (1) and aged surface (15) snow samples at 1‐day intervals in the center of Changchun city, China, which is surrounded by heavy industrial emission sources. We used an advanced computer‐controlled scanning electron microscope to determine particle size and number distributions of three major light‐absorbing particle types with diameters of 0.2–10 μm in seasonal snow, namely soot, dust, and fly ash. Soot and dust particles deposited in various ice‐grain sizes via wet and dry deposition were also examined in terms of their contributions to light absorption and snow albedo reduction. We report here a first attempt to detect a combination of log‐normal soot, dust, and fly ash in seasonal snow, as well as their potential effects on the reduction of snow albedo. Key Points: Computer‐controlled scanning electron microscopy was used to identify size‐resolved light‐absorbing particles in surface snowSoot particle size increases slightly during dry deposition, whereas size‐resolved dust doesn't undergo a significant shift in particle sizeSize‐resolved soot and dust are critical factors in the determination of snow light absorption and albedo [ABSTRACT FROM AUTHOR]

Light‐addressable potentiometric sensor (LAPS) is highly attractive in many sectors, including human disease detection, drug screening, and environmental monitoring. Currently, classical LAPS chips adopt inorganic semiconductors, such as silicon, as the photosensitive layer. Organic semiconductors can provide the next generation of the photosensitive layer because of their high absorption efficiency, large structural variability, eco‐friendliness, and bendability. However, no promising organic materials have been reported so far for the construction of LAPS chips. Here, the authors demonstrate the potential of fullerene (C60), a π‐conjugated carbon molecule with high n‐type conduction, as a candidate material for the photosensitive layer of LAPS. They report on a peculiar bipolar photo‐response under both reverse and forward biased conditions for C60‐based LAPS. An oxygen‐trap‐induced space‐charge mechanism is proposed to explain the unique bipolar photo‐response phenomenon. The proposed C60‐based LAPS exhibits an excellent pH sensitivity of 150 mV/pH as well as a high spatial resolution of 3.8 µm. The authors anticipate that these results will spark interest in this field and enable the replacement of the inorganic‐semiconductor photosensitive layer by organic semiconductor materials for the construction of high‐performance LAPS. [ABSTRACT FROM AUTHOR]

Large diameter bars and high reinforcement ratios – part 1: anchorages and laps According to Eurocode 2, large diameter bars > ∅ 32 mm may only be positioned taking additional rules into account. In contrast, the proposal for Eurocode 2 does not include any additional rules for large diameter bars. The additional rules were investigated with ∅ 40 mm reinforcing bars within two comprehensive experimental investigations at three institutes. After the investigation of ∅ 40 mm reinforcing bars, tests with ∅ 28 mm bars were also conducted to find the connection to conventional bar diameters. This article describes the experimental bond tests conducted at RWTH Aachen University that comprised beam‐end tests, four‐point bending tests with laps and end anchorages in simply supported beams. The test results are used to relax some additional rules. In the following, different design approaches are analysed with a database evaluation for the maximum steel stress to be developed in anchorages and laps. The design approaches for the calculation of necessary anchorage and lap lengths were compared on the basis of a database. [ABSTRACT FROM AUTHOR]

Myhre syndrome ( MS) is a developmental disorder characterized by typical facial dysmorphism, thickened skin, joint limitation and muscular pseudohypertrophy. Other features include brachydactyly, short stature, intellectual deficiency with behavioral problems and deafness. We identified SMAD4 as the gene responsible for MS. The identification of SMAD4 mutations in Laryngotracheal stenosis, Arthropathy, Prognathism and Short stature ( LAPS) cases supports that LAPS and MS are a unique entity. The long-term follow up of patients shows that these conditions are progressive with life threatening complications. All mutations are de novo and changing in the majority of cases Ile500, located in the MH2 domain involved in transcriptional activation. We further showed an impairment of the transcriptional regulation via TGFβ target genes in patient fibroblasts. Finally, the absence of SMAD4 mutations in three MS cases may support genetic heterogeneity. [ABSTRACT FROM AUTHOR]

Light-addressable potentiometric sensors (LAPS) are semiconductor-based potentiometric sensors, with the advantage to detect the concentration of a chemical species in a liquid solution above the sensor surface in a spatially resolved manner. The addressing is achieved by a modulated and focused light source illuminating the semiconductor and generating a concentration-depending photocurrent. This work introduces a LAPS set-up that is able to monitor the electrical impedance in addition to the photocurrent. The impedance spectra of a LAPS structure, with and without illumination, as well as the frequency behaviour of the LAPS measurement are investigated. The measurements are supported by electrical equivalent circuits to explain the impedance and the LAPS-frequency behaviour. The work investigates the influence of different parameters on the frequency behaviour of the LAPS. Furthermore, the phase shift of the photocurrent, the influence of the surface potential as well as the changes of the sensor impedance will be discussed. [ABSTRACT FROM AUTHOR]