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We establish the existence of a cusp in the curvature of a solid sheet at its contact with a liquid subphase.

 

The interface characteristics of the matrix and fibers significantly influence the evolution of residual stress in composite materials. In this study, we provide a methodology for reducing the residual stress in laminated composites by modifying the thermomechanical properties at the fiber–matrix interface. A hydrothermal chemical growth method was used to grow Zinc Oxide nanowires on the carbon fibers. We then utilized a novel digital image correlation approach to evaluate strains and residual stresses, in situ, throughout the autoclave curing of composites. We find that interface modification results in the reduction of residual stress and an increase in laminate strength and stiffness. Upon growing ZnO NWs on the carbon fibers, the maximum in situ in-plane strain components were reduced by approximately 55% and 31%, respectively, while the corresponding maximum residual stresses were decreased by 50.8% and 49.33% for the cross-play laminate [0°/90°] layup in the x and y directions, respectively. For the [45°/-45°] angle ply layup in the x-direction, the strain was decreased by 27.3%, and the maximum residual stress was reduced by 41.5%, whereas in the y-direction, the strain was decreased by 166.3%, and the maximum residual stress was reduced by 17.8%. Furthermore, mechanical testing revealed that the tensile strength for the [45°/-45°] and [0°/90°] laminates increased by 130% and 20%, respectively, with the interface modification. 

Abstract—We conduct the first large-scale user study examining how users interact with an AI Code assistant to solve a variety of security related tasks across different programming languages. Overall, we find that participants who had access to an AI assistant based on OpenAI’s codex-davinci-002 model wrote significantly less secure code than those without access. Additionally, participants with access to an AI assistant were more likely to believe they wrote secure code than those without access to the AI assistant. Furthermore, we find that participants who trusted the AI less and engaged more with the language and format of their prompts (e.g. re-phrasing, adjusting temperature) provided code with fewer security vulnerabilities. Finally, in order to better inform the design of future AI-based Code assistants, we provide an in-depth analysis of participants’ language and interaction behavior, as well as release our user interface as an instrument to conduct similar studies in the future. 

Abstract—We conduct the first large-scale user study examining how users interact with an AI Code assistant to solve a variety of security related tasks across different programming languages. Overall, we find that participants who had access to an AI assistant based on OpenAI’s codex-davinci-002 model wrote significantly less secure code than those without access. Additionally, participants with access to an AI assistant were more likely to believe they wrote secure code than those without access to the AI assistant. Furthermore, we find that participants who trusted the AI less and engaged more with the language and format of their prompts (e.g. re-phrasing, adjusting temperature) provided code with fewer security vulnerabilities. Finally, in order to better inform the design of future AI-based Code assistants, we provide an in-depth analysis of participants’ language and interaction behavior, as well as release our user interface as an instrument to conduct similar studies in the future. 

Variable-pressure electron-beam lithography (VP-EBL) employs an ambient gas at subatmospheric pressures to reduce charging during electron-beam lithography. VP-EBL has been previously shown to eliminate pattern distortion and provide improved resolution when patterning poly(methyl methacrylate) (PMMA) on insulating substrates. However, it remains unknown how water vapor affects the contrast and clearing dose nor has the effect of water vapor on the negative-tone behavior of PMMA been studied. In addition, water vapor has recently been shown to alter the radiation chemistry of the VP-EBL process for Teflon AF. Such changes in radiation chemistry have not been explored for PMMA. In this work, VP-EBL was conducted on conductive substrates to study the effect of water vapor on PMMA patterning separately from the effects of charge dissipation. In addition, both positive and negative-tone processes were studied to determine the effect of water vapor on both chain scission and cross-linking. The contrast of PMMA was found to improve significantly with increasing water vapor pressure for both positive and negative-tone patterning. The clearing dose for positive-tone patterning increases moderately with vapor pressure as would be expected for electron scattering in a gas. However, the onset set dose for negative-tone patterning increased dramatically with pressure revealing a more significant change in the exposure mechanism. X-ray photoelectron spectra and infrared transmission spectra indicate that water vapor only slightly alters the composition of exposed PMMA. Also, electron scattering in water vapor yielded a much larger clear region around negative-tone patterns. This effect could be useful for increasing the range of the developed region around cross-linked PMMA beyond the backscattered electron range. Thus, VP-EBL for PMMA introduces a new means of tuning clearing/onset dose and contrast, while allowing additional control over the size of the cleared region around negative-tone patterns.

 

The over-enrichment of phosphorus in waste streams can lead to eutrophication and oxygen limitations for aquatic life. To understand the release of phosphorus from a soybean processing facility, it is imperative to track the flow of phosphorus in different streams during the processing of soybeans. The objective of the study is to develop process simulation models to study the flow of phosphorus in the soy-biodiesel process and evaluate strategies to mitigate phosphorus release by recovering phosphorous from soapstock and wastewater. Since most of the P is found in soybean meal, the processing of which releases phosphorus, a third case of lecithin recovery was also studied to reduce the amount of phosphorous in soybean meal. It was observed that phosphorus can be economically recovered from the soapstock, as well as the wastewater stream, with an estimated operating cost of USD 1.65 and 3.62 per kg of phosphorous recovered, respectively. The phosphorus recovered from both streams can be potentially applied as fertilizer to more than 13,000 acres of corn or 96,000 acres of soybean, respectively. The lecithin recovery case was found to have the highest revenue, and it led to a 54% reduction in phosphorous during soybean meal processing. 

Abstract Tumor necrosis factor-α-induced protein 8 (TNFAIP8) is a member of the TIPE/TNFAIP8 family which regulates tumor growth and survival. Our goal is to delineate the detailed oncogenic role of TNFAIP8 in skin cancer development and progression. Here we demonstrated that higher expression of TNFAIP8 is associated with basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma development in patient tissues. Induction of TNFAIP8 expression by TNFα or by ectopic expression of TNFAIP8 in SCC or melanoma cell lines resulted in increased cell growth/proliferation. Conversely, silencing of TNFAIP8 decreased cell survival/cell migration in skin cancer cells. We also showed that miR-205-5p targets the 3′UTR of TNFAIP8 and inhibits TNFAIP8 expression. Moreover, miR-205-5p downregulates TNFAIP8 mediated cellular autophagy, increased sensitivity towards the B-RAF V600E mutant kinase inhibitor vemurafenib, and induced cell apoptosis in melanoma cells. Collectively our data indicate that miR-205-5p acts as a tumor suppressor in skin cancer by targeting TNFAIP8.