Beryllium fastener technology

Program was conducted to develop, produce, and test optimum-configuration, beryllium prestressed and blind fasteners. The program was carried out in four phases - phase 1, feasibility study, phase 2, development, phase 3, evaluation of beryllium alloys, and phase 4, fabrication and testing

Extending the theory of Owicki and Gries with a logic of progress

This paper describes a logic of progress for concurrent programs. The logic is based on that of UNITY, molded to fit a sequential programming model. Integration of the two is achieved by using auxiliary variables in a systematic way that incorporates program counters into the program text. The rules for progress in UNITY are then modified to suit this new system. This modification is however subtle enough to allow the theory of Owicki and Gries to be used without change

Which mathematics for the Information Society?

MathIS is a new project that aims to reinvigorate secondary- school mathematics by exploiting insights of the dynamics of algorithmic problem solving. This paper describes the main ideas that underpin the project. In summary, we propose a central role for formal logic, the development of a calculational style of reasoning, the emphasis on the algorithmic nature of mathematics, and the promotion of self-discovery by the students. These ideas are discussed and the case is made, through a number of examples that show the teaching style that we want to introduce, for their relevance in shaping mathematics training for the years to come. In our opinion, the education of software engineers that work effectively with formal methods and mathematical abstractions should start before university and would benefit from the ideas discussed here.Long-term collaboration with J. N. Oliveira on calculational approaches to mathematics is deeply acknowledged. We are also grateful to the anonymous referees for their valuable comments. This research was supported by FCT (the Portuguese Foundation for Science and Technology), in the context of the MATHIS Project under contract PTDC/EIA/73252/2006. The work of Joao F. Ferreira and AlexandraMendeswas further supported by FCT grants SFRH/BD/24269/2005 and SFRH/BD/29553/2006, respectively

Suspension-adapted Chinese hamster ovary-derived cells expressing green fluorescent protein as a screening tool for biomaterials

Synthetic biomaterials play an important role in regenerative medicine. To be effective they must support cell attachment and proliferation in addition to being non-toxic and non-immunogenic. We used a suspension-adapted Chinese hamster ovary-derived cell line expressing green fluorescent protein (GFP) to assess cell attachment and growth on synthetic biomaterials by direct measurement of GFP-specific fluorescence. To simplify operations, all cell cultivation steps were performed in orbitally-shaken, disposable containers. Comparative studies between this GFP assay and previously established cell quantification assays demonstrated that this novel approach is suitable for rapid screening of a large number of samples. Furthermore the utility of our assay system was confirmed by evaluation of cell growth on three polyvinylidene fluoride polymer scaffolds that differed in pore diameter and drawing conditions. The data presented here prove the general utility of GFP-expressing cell lines and orbital shaking technology for the screening of biomaterials for tissue engineering application

Extreme Events, Entrepreneurial Start-Ups, and Innovation: Theoretical Conjectures

Abstract: In light of the COVID-19 pandemic, we scrutinize what has been established in the literature on whether entrepreneurship can cause and resolve extreme events, the immediate and long-run impacts of extreme events on entrepreneurship, and whether extreme events can positively impact (some) entrepreneurship and innovation. Based on this, we utilize a partial equilibrium model to provide several conjectures on the impact of COVID-19 on entrepreneurship, and to derive policy recommendations for recovery. We illustrate that while entrepreneurship recovery will benefit from measures such as direct subsidies for start-ups, firms’ revenue losses, and loan liabilities, it will also benefit from aggregate demand-side support and income redistribution measures, as well as from measures that facilitate the innovation-response to the Keynesian supply-shock caused by the pandemic, such as access to online retail and well-functioning global transportation and logistics

Do Semantics Matter in Empathetic Person Perception of Children or Adults with Mental Illness?

Experiences of stigma, discrimination, or aggression negatively affect the well-being of people experiencing symptoms of psychopathology. However, empathy is thought to undermine prejudice and discrimination and is linked with positive outcomes (e.g., greater well-being, more social support, etc.) among those with stigmatized mental illnesses. The current work investigates the influence of target age (adult or child) and language type (person-first or identity-first) on how much empathic concern perceivers report toward individuals with a hypothetical mental health condition. This research contributes to an ongoing debate about whether person-first or identity-first language carries stigmatizing or protective effects, while also considering a novel potential moderator: target age (i.e., does person-first and identity-first language similarly affect perceptions of adults and children?). To this end, we employed an experimental vignette design examining empathy expressed toward individuals with a mental health condition, where age was manipulated within subjects and language was manipulated between subjects. The results determine that perceivers report greater empathy towards children than adults. However, the use of person-first and identity-first language did not result in significant findings. Thus, whether language type influences empathic concern remains uncertain. These findings suggest a need for increased empirical examination of interventions to inspire empathy towards people, perhaps especially adults, experiencing symptoms of psychopathology

Response of Sorghum Enhanced in Monolignol Biosynthesis to Stalk Rot Pathogens

To increase phenylpropanoid constituents and energy content in the versatile C4 grass sorghum (Sorghum bicolor [L.] Moench), sorghum genes for protiens related to monolignol biosynthesis were overexpressed: SbMyb60 (transcriptional activator), SbPAL (phenylalanine ammonia ase), Bmr2 (4-coumarate: CoA ligase), and SbC3H (coumaroyl shikimate 3-hydroxylase). Overexpression lines were evaluted for responses to stalk pahtogens under greenhouse and field conditions. Greenhouse-grown plants were inoculated with Fusarium thapsinum (Fusarium stalk rot) and Macrophomia phaseolina (charocal rot), which cause yield-reducing diseases. F. thapsinum-inoculated overexpression plants had mean lesion lengths not significantly different than wild-type, except for significantly smaller lesions on two of three SbMyb60 and one of two SbCCoAOMT lines. M. phaseolina-inoculated expression lines had lesions not significantly different from wild-type except one SbPAL line (of two lines studied) with mean lesion lengths significantly larger. Field-grown SbMyb60 and SbCCoAOMT overexpression plants were inoculated with F. thapsinum. Mean lesions of SbMyb60 lines were similar to wild-type, one SbCCoAOMT had larger lesions, whereas the other line was not significantly different than wild-type. Because overexpression of SbMyb60, Bmr2, or SbC3H may not render sorghum more supceptible to stalk rots, these lines may provide sources for development of sorghum with increased phenylpropaniod concentrations

Interaction of (3-Aminopropyl)triethoxysilane with Pulsed Ar-O 2 Afterglow: Application to Nanoparticles Synthesis

International audienceThe interaction of (3-Aminopropyl)triethoxysilane (APTES) with pulsed late Ar-O 2 afterglow is characterized by the synthesis of OH, CO and CO 2 in the gas phase as main by-products. Other minor species like CH, CN and C 2 H are also produced. We suggest that OH radicals are produced in a first step by dehydrogenation of APTES after interaction with oxygen atoms. In a second step, the molecule is oxidized by any O 2 state, to form peroxides that transform into by-products, break thus the precursor CC bonds. If oxidation is limited, i.e. a low duty cycle, fragmentation of the precursor is limited and produced nanoparticles keep the backbone structure of the precursor, but contain amide groups produced from the amine groups initially available in APTES. At high duty cycle, silicon-containing fragments contain some carbon and react together and produce nanoparticles with a non-silica-like structure

Characterization of novel \u3ci\u3eBrown midrib 6\u3c/i\u3e mutations affecting lignin biosynthesis in sorghum

The presence of lignin reduces the quality of lignocellulosic biomass for forage materials and feedstock for biofuels. In C4 grasses, the brown midrib phenotype has been linked to mutations to genes in the monolignol biosynthesis pathway. For example, the Bmr6 gene in sorghum (Sorghum bicolor) has been previously shown to encode cinnamyl alcohol dehydrogenase (CAD), which catalyzes the final step of the monolignol biosynthesis pathway. Mutations in this gene have been shown to reduce the abundance of lignin, enhance digestibility, and improve saccharification efficiencies and ethanol yields. Nine sorghum lines harboring five different bmr6 alleles were identified in an EMS-mutagenized TILLING population. DNA sequencing of Bmr6 revealed that the majority of the mutations impacted evolutionarily conserved amino acids while three-dimensional structural modeling predicted that all of these alleles interfered with the enzyme’s ability to bind with its NADPH cofactor. All of the new alleles reduced in vitro CAD activity levels and enhanced glucose yields following saccharification. Further, many of these lines were associated with higher reductions in acid detergent lignin compared to lines harboring the previously characterized bmr6-ref allele. These bmr6 lines represent new breeding tools for manipulating biomass composition to enhance forage and feedstock quality

Global Responses of Resistant and Susceptible Sorghum (\u3ci\u3eSorghum bicolor\u3c/i\u3e) to Sugarcane Aphid (\u3ci\u3eMelanaphis sacchari\u3c/i\u3e)

The sugarcane aphid (Melanaphis sacchari) has emerged as a significant pest for sorghum. The use of sugarcane aphid-resistant sorghum germplasm with integrated pest management strategies appears to be an excellent solution to this problem. In this study, a resistant line (RTx2783) and a susceptible line (A/BCK60) were used to characterize the differences in plant responses to the sugarcane aphid through a series of experiments, which examined global sorghum gene expression, aphid feeding behavior and inheritance of aphid resistance. The global transcriptomic responses to sugarcane aphids in resistant and susceptible plants were identified using RNA-seq and compared to the expression profiles of uninfested plants at 5, 10, and 15 days post-infestation. The expression of genes from several functional categories were altered in aphid-infested susceptible plants, which included genes related to cell wall modification, photosynthesis and phytohormone biosynthesis. In the resistant line, only 31 genes were differentially expressed in the infested plants relative to uninfested plants over the same timecourse. However, network analysis of these transcriptomes identified a co-expression module where the expression of multiple sugar and starch associated genes were repressed in infested resistant plants at 5 and 10 days. Several nucleotide-binding-site, leucine-rich repeat (NBS-LRR) and disease resistance genes similar to aphid resistance genes identified in other plants are identified in the current study which may be involved in sugarcane aphid resistance. The electrical penetration graph (EPG) results indicated that sugarcane aphid spent approximately twice as long in non-probing phase, and approximately a quarter of time in phloem ingestion phase on the resistant and F1 plants compared to susceptible plant. Additionally, network analysis identified a phloem protein 2 gene expressed in both susceptible and resistant plants early (day 5) of infestation, which may contribute to defense against aphid feeding within sieve elements. The resistant line RTx2783 displayed both antixenosis and antibiosis modes of resistance based on EPG and choice bioassays between susceptible, resistant and F1 plants. Aphid resistance from RTx2783 segregated as a single dominant locus in the F2 generation, which will enable breeders to rapidly develop sugarcane aphid-resistant hybrids using RTx2783 as the male parent