Analysing quadratic effects of formative constructs by means of variance-based structural equation modelling

Together with the development of information systems research, there has also been increased interest in non-linear relationships between focal constructs. This article presents six Partial Least Squares-based approaches for estimating formative constructs’ quadratic effects. In addition, these approaches’ performance is tested by means of a complex Monte Carlo experiment. The experiment reveals significant and substantial differences between the approaches. In general, the performance of the hybrid approach as suggested by Wold (1982) is most convincing in terms of point estimate accuracy, statistical power, and prediction accuracy. The two-stage approach suggested by Chin et al (1996) showed almost the same performance; differences between it and the hybrid approach – although statistically significant – were unsubstantial. Based on these results, the article provides guidelines for the analysis of non-linear effects by means of variance-based structural equation modelling.     

Response of seasonal vegetation development to climatic variations in eastern central Asia

Meteorological records show that central Asia has experienced one of the strongest warming signals in the world over the last 30 years. The objective of this study was to examine the seasonal vegetation response to the recent climatic variation on the Mongolian steppes, the third largest grassland in the world. The onset date of green-up for central Asia was estimated using time-series analysis of advanced very high resolution radiometer (AVHRR) normalized difference vegetation index (NDVI) biweekly composite data collected between January 1982 and December 1991. Monthly precipitation and mean temperature data (1982-1990) were acquired from 19 meteorological stations throughout the grasslands of the eastern Mongolian steppes in China. Our results showed that while the taiga forest north of the Mongolian steppes (>50°N) experienced an earlier onset of green-up during the study period, a later onset was observed at the eastern and northern edges of the Gobi Desert (40°N-50°N). Responses of different vegetation types to climatic variability appeared to vary with vegetation characteristics and spring soil moisture availability of specific sites. Plant stress caused by drought was the most significant contributor to later vegetation green-up as observed from satellite imagery over the desert steppe. Areas with greater seasonal soil moisture greened up earlier in the growing season. Our results suggested that water budget limitations determine the pattern of vegetation responses to atmospheric warming.     

RBS analysis of front contacts for surface-barrier detectors

Surface-barrier detector structures based on Au, WTi and Au/WTi contacts on (111) n-Si were analysed. The metal layers were deposited by evaporation or sputtering to 40–100 nm thicknesses. The aim was to improve the thermal stability of the surface-barrier structures and retain the favourable detector properties of the Au/Si system. Contact structures which contain WTi layers have shown a much better thermal stability compared to the Au/Si system, but the properties of the detectors were poorer. The probable reasons are the reactivity of W and Ti with the thin oxide layer on the silicon surface and perhaps the higher energy of adatoms during sputter-deposition. Both effects can influence the degradation of the surface-barrier properties.     

Tumor-Localized Administration of α-GalCer to Recruit Invariant Natural Killer T Cells and Enhance Their Antitumor Activity against Solid Tumors

Invariant natural killer T (iNKT) cells have the capacity to mount potent anti-tumor reactivity and have therefore become a focus in the development of cell-based immunotherapy. iNKT cells attack tumor cells using multiple mechanisms with a high efficacy; however, their clinical application has been limited because of their low numbers in cancer patients and difficulties in infiltrating solid tumors. In this study, we aimed to overcome these critical limitations by using α-GalCer, a synthetic glycolipid ligand specifically activating iNKT cells, to recruit iNKT to solid tumors. By adoptively transferring human iNKT cells into tumor-bearing humanized NSG mice and administering a single dose of tumor-localized α-GalCer, we demonstrated the rapid recruitment of human iNKT cells into solid tumors in as little as one day and a significantly enhanced tumor killing ability. Using firefly luciferase-labeled iNKT cells, we monitored the tissue biodistribution and pharmacokinetics/pharmacodynamics (PK/PD) of human iNKT cells in tumor-bearing NSG mice. Collectively, these preclinical studies demonstrate the promise of an αGC-driven iNKT cell-based immunotherapy to target solid tumors with higher efficacy and precision.     

AlphaFold2: A Role for Disordered Protein/Region Prediction?

The development of AlphaFold2 marked a paradigm-shift in the structural biology community. Herein, we assess the ability of AlphaFold2 to predict disordered regions against traditional sequence-based disorder predictors. We find that AlphaFold2 performs well at discriminating disordered regions, but also note that the disorder predictor one constructs from an AlphaFold2 structure determines accuracy. In particular, a naïve, but non-trivial assumption that residues assigned to helices, strands, and H-bond stabilized turns are likely ordered and all other residues are disordered results in a dramatic overestimation in disorder; conversely, the predicted local distance difference test (pLDDT) provides an excellent measure of residue-wise disorder. Furthermore, by employing molecular dynamics (MD) simulations, we note an interesting relationship between the pLDDT and secondary structure, that may explain our observations and suggests a broader application of the pLDDT for characterizing the local dynamics of intrinsically disordered proteins and regions (IDPs/IDRs).     

Study of the adhesion of Staphylococcus aureus to coated glass substrates

The adhesion of Staphylococcus aureus was studied using a selection of laboratory-prepared and commercially available coated glass substrates using a simple methodology. Substrates were examined by scanning electron microscopy, atomic force microscopy and water droplet contact angles. It was found that microbial adhesion was independent of surface roughness, when this was of a lower magnitude than microbial size. It was also found that microbial adhesion was greater for hydrophilic surfaces than for hydrophobic ones, but that on a photoinduced superhydrophilic surface, microbes were more spread out—a potential benefit for more effective photocatalytic disinfection. It is suggested that hydrophobic and photoinduced superhydrophilic surface coatings both have potential as a means of reducing microbial fouling of surfaces.     

消除产品良率隐藏的杀手--电子束检查是铜逻辑和晶圆代工厂的最佳方法

监控和消除隐藏的电路缺陷已成为130nm和130nm以下器件的关键。这使得电子束检查正在广泛应用于开发、试生产和量产的监控过程。我们将描述当前铜逻辑和晶圆代工厂电子束检查技术的执行情况,其中包括详细的案例研究,它说明了从开发到量产过程中应用电子束检查技术的好处。我们也描述了过去克服通用工具障碍的方法。然后,分别介绍了利用电子束检查技术的新进展,以及为假设的20000WSPMφ300mm工厂模拟的最理想执行情况的最佳实例。     

Performance Evaluation of a Novel Converged Architecture for Digital-Video Transmission Over Optical Wireless Channels

A robust channel coding architecture for multigigabit-per-second digital-video transmission over the optical wireless channel is introduced and evaluated. The proposed scheme combines low-density parity-check coding with channel interleaving to improve the transmission over turbulent temporally correlated optical wireless channels while satisfying real-time video delay constraints. Frame error rates of the presented code design are evaluated via simulation for intensity-modulation/direct-detection optical wireless links in both lognormal- and Rayleigh-fading channels. Results indicate that the performance of the proposed system is effective across a large range of atmospheric turbulence strengths and achieves significant temporal diversity in moderately long (10 ms) temporal correlation times while satisfying a 0.3-s real-time delay constraint. Moreover, the proposed design is shown to outperform the Reed-Solomon codes prevalent in the legacy fiber and wireless digital-television distribution systems.