Development of a fiber optic high temperature strain sensor

From 1 Apr. 1991 to 31 Aug. 1992, the Georgia Tech Research Institute conducted a research program to develop a high temperature fiber optic strain sensor as part of a measurement program for the space shuttle booster rocket motor. The major objectives of this program were divided into four tasks. Under Task 1, the literature on high-temperature fiber optic strain sensors was reviewed. Task 2 addressed the design and fabrication of the strain sensor. Tests and calibration were conducted under Task 3, and Task 4 was to generate recommendations for a follow-on study of a distributed strain sensor. Task 4 was submitted to NASA as a separate proposal

Indicators of Resiliency Among Urban Elementary School Students At-Risk

This study was designed to investigate the phenomenon of resiliency among urban elementary school students in an at-risk environment. In contrast with previous studies narrowly focused upon the identification of risk factors, this study utilized a phenomenological qualitative approach to investigate indicators of resiliency from both individual and contextual perspectives. The narrative descriptions of 25 elementary school students in an at-risk environment were analyzed. The results indicated that the participants had strong individual and contextual resiliency indicators through the fifth grade despite being educated in a school district with almost a 60% drop-out rate before high school graduation

Nucleotide sequence of the luxA gene of Vibrio harveyi and the complete amino acid sequence of the alpha subunit of bacterial luciferase

The nucleotide sequence of the 1.85-kilobase EcoRI fragment from Vibrio harveyi that was cloned using a mixed-sequence synthetic oligonucleotide probe (Cohn, D. H., Ogden, R. C., Abelson, J. N., Baldwin, T. O., Nealson, K. H., Simon, M. I., and Mileham, A. J. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 120-123) has been determined. The alpha subunit-coding region (luxA) was found to begin at base number 707 and end at base number 1771. The alpha subunit has a calculated molecular weight of 40,108 and comprises a total of 355 amino acid residues. There are 34 base pairs separating the start of the alpha subunit structural gene and a 669-base open reading frame extending from the proximal EcoRI site. At the 3' end of the luxA coding region there are 26 bases between the end of the structural gene and the start of the luxB structural gene. Approximately two-thirds of the alpha subunit was sequenced by protein chemical techniques. The amino acid sequence implied by the DNA sequence, with few exceptions, confirmed the chemically determined sequence. Regions of the alpha subunit thought to comprise the active center were found to reside in two discrete and relatively basic regions, one from around residues 100-115 and the second from around residues 280-295

Computational modeling of growth: systemic and pulmonary hypertension in the heart

We introduce a novel constitutive model for growing soft biological tissue and study its performance in two characteristic cases of mechanically induced wall thickening of the heart. We adopt the concept of an incompatible growth configuration introducing the multiplicative decomposition of the deformation gradient into an elastic and a growth part. The key feature of the model is the definition of the evolution equation for the growth tensor which we motivate by pressure-overload-induced sarcomerogenesis. In response to the deposition of sarcomere units on the molecular level, the individual heart muscle cells increase in diameter, and the wall of the heart becomes progressively thicker. We present the underlying constitutive equations and their algorithmic implementation within an implicit nonlinear finite element framework. To demonstrate the features of the proposed approach, we study two classical growth phenomena in the heart: left and right ventricular wall thickening in response to systemic and pulmonary hypertension

VISOR: a versatile haplotype-aware structural variant simulator for short- and long-read sequencing.

Abstract Summary VISOR is a tool for haplotype-specific simulations of simple and complex structural variants (SVs). The method is applicable to haploid, diploid or higher ploidy simulations for bulk or single-cell sequencing data. SVs are implanted into FASTA haplotypes at single-basepair resolution, optionally with nearby single-nucleotide variants. Short or long reads are drawn at random from these haplotypes using standard error profiles. Double- or single-stranded data can be simulated and VISOR supports the generation of haplotype-tagged BAM files. The tool further includes methods to interactively visualize simulated variants in single-stranded data. The versatility of VISOR is unmet by comparable tools and it lays the foundation to simulate haplotype-resolved cancer heterogeneity data in bulk or at single-cell resolution. Availability and implementation VISOR is implemented in python 3.6, open-source and freely available at https://github.com/davidebolo1993/VISOR. Documentation is available at https://davidebolo1993.github.io/visordoc/. Supplementary information Supplementary data are available at Bioinformatics online

Recommendations for the Use of Programmable Logic Controllers (PLCs) at CERN

Programmable Logic Controllers (PLCs) have been increasingly used at CERN for several years. In future control solutions, PLCs will initially be considered for the rejuvenation of old and obsolete systems, and then for the control of new equipment to be installed in technical services, accelerators and experiments. Many industrial systems will be installed for the control of equipment during the next 5 to 10 years, particularly for the construction of the LHC project. In order to increase efficiency, to reduce the initial investment and to minimise the long term maintenance costs in terms of money and human resources the Working Group recommends that all CERN equipment control projects, based on PLCs, select or specify PLCs from the product lines of the recommended PLC manufacturers

The Future of U.S. Natural Gas Production, Use, and Trade

Abstract and PDF report are also available on the MIT Joint Program on the Science and Policy of Global Change website (http://globalchange.mit.edu/)Two computable general equilibrium models, one global and the other providing U.S. regional detail, are applied to analysis of the future of U.S. natural gas as an input to an MIT study of the topic. The focus is on uncertainties including the scale and cost of gas resources, the costs of competing technologies, the pattern of greenhouse gas mitigation, and the evolution of global natural gas markets. Results show that the outlook for gas over the next several decades is very favorable. In electric generation, given the unproven and relatively high cost of other low-carbon generation alternatives, gas likely is the preferred alternative to coal. A broad GHG pricing policy would increase gas use in generation but reduce use in other sectors, on a balance increasing its role from present levels. The shale gas resource is a major contributor to this optimistic view of the future of gas, but it is far from a panacea over the longer term. Gas can be an effective bridge to a lower emissions future, but investment in the development of still lower CO2 technologies remains an important priority. Also, international gas resources may well prove to be less costly than those in the U.S., except for the lowest-cost domestic shale resources, and the emergence of an integrated global gas market could result in significant U.S. gas imports.American Clean Skies Foundation, with additional support from the Hess Corporation, the Agencia Nacional de Hidrocarburos (Columbia), the Energy Futures Coalition, and the MIT Energy Initiative

Studying boundary layer methane isotopy and vertical mixing processes at a rewetted peatland site using an unmanned aircraft system

The combination of two well-established methods, of quadrocopter-borne air sampling and methane isotopic analyses, is applied to determine the source process of methane at different altitudes and to study mixing processes. A proof-of-concept study was performed to demonstrate the capabilities of quadrocopter air sampling for subsequently analysing the methane isotopic composition δ13C in the laboratory. The advantage of the system compared to classical sampling on the ground and at tall towers is the flexibility concerning sampling location, and in particular the flexible choice of sampling altitude, allowing the study of the layering and mixing of air masses with potentially different spatial origin of air masses and methane. Boundary layer mixing processes and the methane isotopic composition were studied at Polder Zarnekow in Mecklenburg–West Pomerania in the north-east of Germany, which has become a strong source of biogenically produced methane after rewetting the drained and degraded peatland. Methane fluxes are measured continuously at the site. They show high emissions from May to September, and a strong diurnal variability. For two case studies on 23 May and 5 September 2018, vertical profiles of temperature and humidity were recorded up to an altitude of 650 and 1000 m, respectively, during the morning transition. Air samples were taken at different altitudes and analysed in the laboratory for methane isotopic composition. The values showed a different isotopic composition in the vertical distribution during stable conditions in the morning (delta values of −51.5 ‰ below the temperature inversion at an altitude of 150 m on 23 May 2018 and at an altitude of 50 m on 5 September 2018, delta values of −50.1 ‰ above). After the onset of turbulent mixing, the isotopic composition was the same throughout the vertical column with a mean delta value of −49.9 ± 0.45 ‰. The systematically more negative delta values occurred only as long as the nocturnal temperature inversion was present. During the September study, water samples were analysed as well for methane concentration and isotopic composition in order to provide a link between surface and atmosphere. The water samples reveal high variability on horizontal scales of a few tens of metres for this particular case. The airborne sampling system and consecutive analysis chain were shown to provide reliable and reproducible results for two samples obtained simultaneously. The method presents a powerful tool for distinguishing the source process of methane at different altitudes. The isotopic composition showed clearly depleted delta values directly above a biological methane source when vertical mixing was hampered by a temperature inversion, and different delta values above, where the air masses originate from a different footprint area. The vertical distribution of methane isotopic composition can serve as tracer for mixing processes of methane within the atmospheric boundary layer