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The in situ dry matter disappearance technique (Ørskov and McDonald, 1979) evaluates forages for their rate and extent of degradation in the rumen. However, this method does not allow the evaluation of a large number of samples at one and the same time and therefore which limits screening of treatments applied to forages. The in vitro gas production method is faster and allows handling of many samples per batch; therefore, gas production could be an alternative to the use of nylon bags if the response to treatments between the two methods is similar among treated forages. The objective of this experiment was to compare results obtained with both the gas production and the nylon bag techniques for forages treated with four levels of maceration and conserved as hay or silage.
Gloss, Carr, Reichman, Abdul-Nasiru, and Oestereich (2017) present a compelling argument (or rallying call) for there being a “moral imperative for I-O psychology to overrepresent people living in the deepest forms of poverty in both science and practice” (p. 330). We agree. Our research has been dominated by a POSH perspective, and it is incumbent upon us to ensure that our science benefits those who are most affected by poverty. We believe the interest in engaging in humanitarian work psychology is growing among industrial and organizational (I-O) psychologists, yet many of us may not feel prepared to conduct such research and/or we may feel that we lack the skills to do so. Further, as Gloss et al. (2017) note, to the extent that we are unprepared to engage in research that benefits those living in poverty, in particular, we run the added risk of harming the very populations we are wanting to help. As such, the interest is there, but we may be daunted by the method. We argue that in order to heed that rallying call, without harm, we need to develop our own capabilities to engage in this important work.
The loss of natural habitats is a major threat to biodiversity, and protected area designation is one of the standard responses to this threat. However, greater understanding of the drivers of habitat loss and of the circumstances under which protected areas succeed or fail is still needed. We use visual assessment of satellite images to quantify land-cover change over periods of up to 30 years in and around a matched sample of protected and unprotected Important Bird and Biodiversity Areas (IBAs) in Africa. We modelled the annual survival of forests and other natural land covers as a function of a range of environmental and anthropic predictors of plausible drivers. The best-supported model indicated that survival rates of natural land cover were highest in steeper areas, at higher altitudes, in areas with lower human population densities and in areas where the cover of natural habitats was already higher at the start of the period. Survival rates of natural land cover in protected areas were, on average, around twice those in unprotected areas, but the differences between them varied along different environmental gradients. The overall survival rates of both protected and unprotected forests were significantly lower than those of other natural land-cover types, but the net benefit of protection, in terms of the absolute difference in rates of loss between protected and unprotected sites, was higher in forests. Interaction terms indicated that as slope and altitude increased, the natural protection offered by topography increasingly nullified the additional benefits of legislative protection. Furthermore, protected area designation offered reduced additional benefits to the survival of natural land cover in areas where rates of conversion were higher at the start of the observation period. Variation in the impacts of protected area status along different environmental gradients indicates that targets to improve the world's protected area network, such as Aichi Target 11 of the Convention on Biological Diversity, need to look beyond simple area-based metrics. Our methods and results contribute to the development of a protocol for prioritizing places where protection is likely to have the greatest effect.
BOUT++ is a 3D nonlinear finite-difference plasma simulation code, capable of solving quite general systems of Partial Differential Equations (PDEs), but targeted particularly on studies of the edge region of tokamak plasmas. BOUT++ is publicly available, and has been adopted by a growing number of researchers worldwide. Here we present improvements which have been made to the code since its original release, both in terms of structure and its capabilities. Some recent applications of these methods are reviewed, and areas of active development are discussed. We also present algorithms and tools which have been developed to enable creation of inputs from analytic expressions and experimental data, and for processing and visualisation of output results. This includes a new tool Hypnotoad for the creation of meshes from experimental equilibria. Algorithms have been implemented in BOUT++ to solve a range of linear algebraic problems encountered in the simulation of reduced Magnetohydrodynamics (MHD) and gyro-fluid models: A preconditioning scheme is presented which enables the plasma potential to be calculated efficiently using iterative methods supplied by the PETSc library (the Portable, Extensible Toolkit for Scientific Computation) (Balay et al. 2014), without invoking the Boussinesq approximation. Scaling studies are also performed of a linear solver used as part of physics-based preconditioning to accelerate the convergence of implicit time-integration schemes.
Clovis sites occur throughout the southwestern United States and northwestern Mexico, but are poorly documented in the central Rio Grande rift region. Here, we present data from two relatively unknown Clovis projectile point assemblages from this region: the first is from the Mockingbird Gap Clovis site and the second is from a survey of the surrounding region. Our goals are to reconstruct general features of the paleoecological adaptation of Clovis populations in the region using raw material sourcing and then to compare the point technology in the region to other Clovis assemblages in the Southwest and across the continent. Our results show that both assemblages were manufactured from similar suites of raw materials that come almost exclusively from the central Rio Grande rift region and the adjacent mountains of New Mexico. Additionally, we show that Clovis projectile points in the study region are significantly smaller than the continental average. Our results suggest that Clovis populations in this region operated within a large, well-known, and relatively high-elevation territory encompassing much of northern and western New Mexico.
Several neuroimaging studies have investigated brain grey matter in people with body dysmorphic disorder (BDD), showing possible abnormalities in the limbic system, orbitofrontal cortex, caudate nuclei and temporal lobes. This study takes these findings forward by investigating white matter properties in BDD compared with controls using diffusion tensor imaging. It was hypothesized that the BDD sample would have widespread significantly reduced white matter connectivity as characterized by fractional anisotropy (FA).
A total of 20 participants with BDD and 20 healthy controls matched on age, gender and handedness underwent diffusion tensor imaging. FA, a measure of water diffusion within a voxel, was compared between groups on a voxel-by-voxel basis across the brain using tract-based spatial statistics within the FSL package.
Results showed that, compared with healthy controls, BDD patients demonstrated significantly lower FA (p < 0.05) in most major white matter tracts throughout the brain, including in the superior longitudinal fasciculus, inferior fronto-occipital fasciculus and corpus callosum. Lower FA levels could be accounted for by increased radial diffusivity as characterized by eigenvalues 2 and 3. No area of higher FA was found in BDD.
This study provided the first evidence of compromised white matter integrity within BDD patients. This suggests that there are inefficient connections between different brain areas, which may explain the cognitive and emotion regulation deficits within BDD patients.
The Hayes-Martin manoeuvre involves ligation of the posterior facial vein and superior reflection of the investing fascia below the mandible to preserve the marginal mandibular nerve. The peri-facial nodes thus remain undissected. We perform this manoeuvre routinely during modified radical neck dissection for metastatic oropharyngeal squamous cell cancer. Here, we review the oncological safety and marginal mandibular nerve preservation rates of this manoeuvre from 2004 to 2009.
Retrospective review of the head and neck oncology database (2004–2009) at Addenbrooke's Hospital, Cambridge, UK, a tertiary referral centre for head and neck oncology.
Thirty-four patients underwent modified radical neck dissection for metastatic oropharyngeal squamous cell carcinoma. The primary tumour included the tonsil in 19 cases, base of tongue in 10 and posterior pharyngeal wall in 5. The neck nodal status was N1 in 4 cases, N2a in 11, N2b in 10, N2c in 4 and N3 in 5. All patients had adjuvant radiotherapy. Median follow up was four years (range, two to five). No peri-facial nodal region recurrences were seen. Four patients had temporary marginal mandibular nerve weakness; beyond two months, no weakness was seen.
In neck dissections for oropharyngeal squamous cell carcinoma, the marginal mandibular nerve and accompanying facial nodes can be safely preserved without oncological risk using the Hayes-Martin manoeuvre.
We document patterns of distribution and relative abundance of marine megavertebrate fauna around Cornwall and the Isles of Scilly from a combination of aerial and boat-based surveying. Between January 2006 and November 2007, 20 aerial surveys were undertaken, comprising over 40 hours of on-effort flying time. In April to October of these years, 27 effort-corrected ferry surveys were also conducted from a passenger ferry travelling between Cornwall and the Isles of Scilly. Opportunistic sightings were also logged by the crew members of the ferry and another vessel travelling regularly along the same route on 155 days. Ten megavertebrate species were sighted: basking sharks Cetorhinus maximus, sunfish Mola mola, common dolphins Delphinus delphis, harbour porpoise Phocoena phocoena, grey seals Halichoerus grypus, Risso's dolphins Grampus griseus, bottlenose dolphins Tursiops truncatus, minke whales Balaenoptera acutorostrata, long-finned pilot whales Globicephala melas and killer whale Orcinus orca. During aerial surveys, 206 sighting events of seven species were made, compared with 145 sighting events of eight species during ferry surveys and 293 sighting events of 10 species from opportunistic ship-board data collection efforts. Seasonal and spatial patterns in species occurrence were evident. Basking sharks were the most commonly-sighted species in the region and were relatively abundant throughout the estimated 5 km-wide strip of coastal waters covered by the aerial surveys, during spring and summer. Ferry surveys and opportunistic vessel-based sightings data confirmed that the distribution of surface-feeding aggregations of this species was largely around the coasts. Despite the limited scope of this study, it has provided valuable baseline data, and possible insights into the marine biodiversity of the region.
InGaN alloys are widely researched in diverse optoelectronic applications. This material has also been demonstrated as a photovoltaic material. This paper presents the study to achieve optimum electrically active p-type InGaN epi-layers. Mg doped InGaN films with 20% In composition are grown on GaN templates/sapphire substrates by MOCVD. It is found that the hole concentration of p-type InGaN depends strongly on the Mg flow rate and V/III molar ratio and hole concentration greater than 2×1019 cm−3 has been achieved at room temperature. The optimum activation temperature of Mg-doped InGaN layer has been found to be 550-600°C, which is lower than that of Mg-doped GaN. A solar cell was realized successfully using the InGaN epi-layers presented here.
This study presents two methods for preparing the High Tc superconducting YBa2Cu3O7−x compound. Aqueous nitrate solutions consisting of Yttrium, Barium and Copper were mixed, dried, blended and the resulting homogeneous mixture calcined at 700–900°C for 2–4h to develop the superconducting (1,2,3) phase. As an alternative, oxalates of Yttrium, Copper and Barium were coprecipitated from the mixed metal nitrate solution using (Et3NH)2C2O4. The resulting pale blue coprecipitate was dried and calcined in air at 700–900°C/2–4h. Both methods provided high homogeneity precursors for the High Tc YBa2Cu3O7−x superconductor. Resistance measurements, SEM, x-ray and VSM were used to characterize the microstructures and properties.
Although silicon-on-insulator (SOI) materials made by standard energy (150–200 keV) SIMOX processes have shown great promise for meeting the needs of radiation hard microelectronics, there are still problems relating to the radiation hardness and economic viability of standard SIMOX. A low energy SIMOX (LES) process reduces cost and improves radiation hardness and increased throughput of any implanter because much smaller doses are required. In addition, the process is uniquely able to produce high quality thin SIMOX structures that are of particular interest for fully depleted device structures. In this paper, we address the formation of high quality ultrathin SIMOX structures by low energy implantation.
Substantial reduction of defect density in silicon-on-sapphire (SOS) material is required to broaden its range of applications to include CMOS and bipolar devices. In recent years, solid phase epitaxy and regrowth (SPEAR) and double solid phase epitaxy (DSPE) processes were applied to SOS to reduce the density of defects in the silicon. These methods result in improved carrier mobilities, but also in increased leakage current, even before irradiation. In a radiation environment, this material has a large increase in radiation induced back channel leakage current as compared to standard wafers. In other words, the radiation hardness quality of the SOS declines when the crystalline quality of the Si near the sapphire interface is improved.
In this paper, we will demonstrate that Ge implantation, rather than Si implantation normally employed in DSPE and SPEAR processes, is an efficient and more effective way to reduce the density of defects near the surface silicon region without improving the Si/sapphire interface region. Ge implantation may be used to engineer defects in the Si/sapphire interface region to eliminate back channel leakage problems.
Single shot pulses from a Nd:YAG laser were used to generate different sized holes and patterns in tape-cast ceramic sheets for electronic packaging applications. The ceramic sheets were based on formulations in the BaTiO3 and MgO-Al2O3-SiO2 systems. The single shot laser pulses were targeted using a computer controlled mirror deflection system and a programmed (cavitation) pattern which could readily be modified. Morphology and structure of the drilled holes before and after sintering were examined by SEM. The surface radial temperature profile resulting from the laser pulse was directly mapped using a lacquer thermocoat. Effects of the laser pulse energy and beam spot size on laser/ceramic interactions and cavitation process were also explored.
CoSi2, or TiSi2 formation on gate polysilicon can degrade the current-voltage and capacitance-voltage characteristics of MOS capacitors. Degradation of the gate oxide breakdown field is much more severe for capacitors with TiSi2 than for those with COSi2 TEM reveals evidence for a reaction at the interface between TiSi2 and SiO2, whereas there is no observable reaction between COSi2 and SiO2- The low breakdown fields for devices with TiSi2 may be due to thinning of the gate oxide by the interfacial reaction or mechanical deformation. A high density of electron traps and a small reduction in the breakdown field is observed when COSi2 contacts the gate, possibly due to a compressive stress in the oxide exerted by the suicide. In addition, an increase in the interface state density at the Si-SiO2 interface is seen for all samples exposed to a rapid thermal anneal (RTA) at 800°C, possibly due to the release of H from dangling bonds.
Silicon-on-insulator (SOI) wafers made by standard energy (150–200 keV) Separation by IMplantation of Oxygen (SIMOX) processes have shown great promise for meeting the needs of radiation-hard microelectronics. However, if SIMOX material is to become a competitive substrate material for manufacturing commercial integrated circuits, the cost of the SIMOX wafers must be greatly reduced. The low energy SIMOX (LES) process accomplishes the needed reduction in cost by producing ultrathin layers which require much lower ion doses. These ultrathin layers are necessary for the next generation of commercial ultra high density CMOS integrated circuits, and must be of very high quality to be utilized for commercial applications. In this paper we discuss characterization of ultrathin LES structures.