Nitrate and Inhibition of Ruminal Methanogenesis : Microbial Ecology, Obstacles, and Opportunities for Lowering Methane Emissions from Ruminant Livestock

Acknowledgments CY was supported by a scholarship from the China Scholarship Council. IC was supported by the SRUC International Engagement Strategy Fund. The nitrate project was funded by EBLEX, a Division of the Agriculture and Horticulture Development Board. RINH and SRUC are funded by the Rural and Environment Science and Analytical Services Division (RESAS) of the Scottish Government.Peer reviewedPublisher PD

High-K materials and metal gates for CMOS applications

The scaling of complementary metal oxide semiconductor (CMOS) transistors has led to the silicon dioxide layer used as a gate dielectric becoming so thin that the gate leakage current becomes too large. This led to the replacement of SiO2 by a physically thicker layer of a higher dielectric constant or ‘high-K’ oxide such as hafnium oxide. Intensive research was carried out to develop these oxides into high quality electronic materials. In addition, the incorporation of Ge in the CMOS transistor structure has been employed to enable higher carrier mobility and performance. This review covers both scientific and technological issues related to the high-K gate stack – the choice of oxides, their deposition, their structural and metallurgical behaviour, atomic diffusion, interface structure, their electronic structure, band offsets, electronic defects, charge trapping and conduction mechanisms, reliability, mobility degradation and oxygen scavenging to achieve the thinnest oxide thicknesses. The high K oxides were implemented in conjunction with a replacement of polycrystalline Si gate electrodes with metal gates. The strong metallurgical interactions between the gate electrodes and the HfO2 which resulted an unstable gate threshold voltage resulted in the use of the lower temperature ‘gate last’ process flow, in addition to the standard ‘gate first’ approach. Work function control by metal gate electrodes and by oxide dipole layers is discussed. The problems associated with high K oxides on Ge channels are also discussed.RMW acknowledges an IBM Faculty award and JR acknowledges funding from EPSRC.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.mser.2014.11.00

Computer control of a scanning electron microscope for digital image processing of thermal-wave images

Using a recently developed technology called thermal-wave microscopy, NASA Lewis Research Center has developed a computer controlled submicron thermal-wave microscope for the purpose of investigating III-V compound semiconductor devices and materials. This paper describes the system's design and configuration and discusses the hardware and software capabilities. Knowledge of the Concurrent 3200 series computers is needed for a complete understanding of the material presented. However, concepts and procedures are of general interest

Maintenance energy and molar growth yields of Escherichia coli

Maintenance is that fraction of the metabolic activity of growing cells which does not result in the net synthesis of new cell material. The maintenance coefficient (m) is assumed to be constant, and independent of specific growth rate (mu). It can be measured by, examining the distribution of carbon to new cells and to energy production at various mu. In the arithmetic growth systems employed in this work mu changes in a predictable way and at the slow growth rates attained (mu = 0.01 - 0.1 h-1) m is a large fraction of the total energy utilisation. These factors made more simple the accurate measurement of m in comparison with methods employed by other workers. Both the maximum molar growth yield (YG) and m were readily measured using arithmetic-type continuous culture. Value of YG and YGO2 were similar to those obtained by other workers using different growth systems. The main conclusions were (i) anabolic and catabolic processes in carbon-limited were tightly coupled, but coupling broke down under nitrogen limitation; (ii) using the Bauchop and Elsden YATP of 10.5 g/mole, P/0 ratios for carbon-limited E. coli were 2 for growth on glucose, malate and glycerol, and 3 for growth on lactose. Addition of 0.5 M sodium chloride to a glycerol-limited culture reduced the P/0 ratio to 1. These P/0 ratios seemed reasonable, implying that the previous assumption of the value for YATP was probably valid, and hence YATP was considerably less than the theoretical maximum of ~30 g/mole. Maintenance in terms of carbon source and oxygen was measured in the same experiments. Findings were (i) carbon source used for maintenance was completely oxidised; (ii) maintenance energy is small in E. coli. mATP was 1 - 3 mmol (g dry wt)-1 h-1 at 3

Continental breakup and UHP rock exhumation in action: GPS results from the Woodlark Rift, Papua New Guinea

We show results from a network of campaign Global Positioning System (GPS) sites in the Woodlark Rift, southeastern Papua New Guinea, in a transition from seafloor spreading to continental rifting. GPS velocities indicate anticlockwise rotation (at 2–2.7°/Myr, relative to Australia) of crustal blocks north of the rift, producing 10–15 mm/yr of extension in the continental rift, increasing to 20–40 mm/yr of seafloor spreading at the Woodlark Spreading Center. Extension in the continental rift is distributed among multiple structures. These data demonstrate that low-angle normal faults in the continents, such as the Mai'iu Fault, can slip at high rates nearing 10 mm/yr. Extensional deformation observed in the D'Entrecasteaux Islands, the site of the world's only actively exhuming Ultra-High Pressure (UHP) rock terrane, supports the idea that extensional processes play a critical role in UHP rock exhumation. GPS data do not require significant interseismic coupling on faults in the region, suggesting that much of the deformation may be aseismic. Westward transfer of deformation from the Woodlark Spreading Center to the main plate boundary fault in the continental rift (the Mai'iu fault) is accommodated by clockwise rotation of a tectonic block beneath Goodenough Bay, and by dextral strike slip on transfer faults within (and surrounding) Normanby Island. Contemporary extension rates in the Woodlark Spreading Center are 30–50% slower than those from seafloor spreading-derived magnetic anomalies. The 0.5 Ma to present seafloor spreading estimates for the Woodlark Basin may be overestimated, and a reevaluation of these data in the context of the GPS rates is warranted

Application of Real Time Inverse Eddy Current Analysis

Rapid reduction of multifrequency eddy current data to direct material properties of conductivity and dimension has been a task for a number of years by Wallace et al. (1) and Seigfried (2,3). The direct solution of the electromagnetic boundary value problem and fitting data to experimental data can be accomplished but is slow and tedious(4,5,6). The direct solution approach has a slow cycle time and reduces both the spontaneous interaction of the operator to the test in progress and the resulting understanding of the process. The inverse approach of taking the raw eddy current data and producing physical data rapidly opens two possibilities for the measurement technique. In the area of process development and in difficult environments such as crystal growers, chemical reactors or heat treatment furnaces. It is possible to detect and stimulate transient events and isolate these reaction rapidly. Extending this application to automated operation one can use the resulting inverse data for control particularly in temperature measurement, where there is a conductivity dependence on temperature

PCDDB: new developments at the Protein Circular Dichroism Data Bank

The Protein Circular Dichroism Data Bank (PCDDB) has been in operation for more than 5 years as a public repository for archiving circular dichroism spectroscopic data and associated bioinformatics and experimental metadata. Since its inception, many improvements and new developments have been made in data display, searching algorithms, data formats, data content, auxillary information, and validation techniques, as well as, of course, an increase in the number of holdings. It provides a site (http://pcddb.cryst.bbk.ac.uk) for authors to deposit experimental data as well as detailed information on methods and calculations associated with published work. It also includes links for each entry to bioinformatics databases. The data are freely available to accessors either as single files or as complete data bank downloads. The PCDDB has found broad usage by the structural biology, bioinformatics, analytical and pharmaceutical communities, and has formed the basis for new software and methods developments

Twelfth award of the Medal of the Seismological Society of America

The medal of the Seismological Society of America was established as Article XII of the Constitution and Bylaws in the 1975 annual election. The Medal recognizes outstanding contributions in Seismology and Earthquake Engineering. The twelfth award, in 1989, was made to Dr. Robert E. Wallace