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Are interpersonal comparisons of desire possible? Can we give an account of how facts about desires are grounded that underpins such comparisons? This paper supposes the answer to the first question is yes, and provides an account of the nature of desire that explains how this is so. The account is a modification of the interpretationist metaphysics of representation that the author has recently been developing. The modification is to allow phenomenological affective valence into the "base facts" on which correct interpretation is grounded. To use this extra resource within that theory to vindicate interpersonal comparisons, we will need to appeal rational connections between level of valence and level of desire, which this paper sets out and examines. [ABSTRACT FROM AUTHOR]

Information can be public among a group. Whether or not information is public matters, for example, for accounts of interdependent rational choice, of communication, and of joint intention. A standard analysis of public information identifies it with (some variant of) common belief. The latter notion is stipulatively defined as an infinite conjunction: for p to be commonly believed is for it to believed by all members of a group, for all members to believe that all members believe it, and so forth. This analysis is often presupposed without much argument in philosophy. Theoretical entrenchment or intuitions about cases might give some traction on the question, but give little insight about why the identification holds, if it does. The strategy of this paper is to characterize a practical-normative role for information being public, and show that the only things that play that role are (variants of) common belief as stipulatively characterized. In more detail: a functional role for "taking a proposition for granted" in non-isolated decision making is characterized. I then present some minimal conditions under which such an attitude is correctly held. The key assumption links this attitude to beliefs about what is public. From minimal a priori principles, we can argue that a proposition being public among a group entails common commitment to believe among that group. Later sections explore partial converses to this result, the factivity of publicity and publicity from the perspective of outsiders to the group, and objections to the aprioricity of the result deriving from a posteriori existential presuppositions. [ABSTRACT FROM AUTHOR]

Sinking particles are important in delivering carbon to the deep ocean where it may be stored out of contact with the atmosphere. Whilst particle sinking velocities are known to be influenced by a multitude of factors, size‐based parameterizations remain common in biogeochemical models and in the methods used to determine particulate fluxes from autonomous platforms. Here we carried out an extensive literature review (62 data sets) into the size‐sinking velocity relationship, and find the relationship is much weaker for studies examining particles in situ (median R2 = 0.09) compared with ex situ studies (median R2 = 0.35). This discrepancy may be because particles examined in the laboratory have more uniform properties than those studied in situ. Our review highlights the shortcomings of using a simple relationship between size and sinking velocity to calculate sinking particulate fluxes in the ocean; considering additional particle characteristics will enable more accurate calculations of particulate fluxes. Plain Language Summary: Sinking particles are important in delivering carbon to the deep ocean where it may be stored out of contact with the atmosphere. Sinking particle speeds are an important control on sinking particle fluxes, and are known to be influenced by many factors. However, methods used to study particle fluxes from particle image data sets commonly place size as an important determinant of sinking speed. Here we carried out an extensive literature review into the size‐sinking speed relationship, and find the relationship is much weaker for studies measuring particle sinking speeds in the ocean (in situ studies) compared with studies measuring sinking speeds in the laboratory (ex situ studies). This may be because other particle characteristics that can also influence particle sinking speeds are more constant in ex situ studies, allowing size to exert a stronger control on particle sinking speed. These results have implications for the use of novel in‐situ imaging methods to calculate sinking particle fluxes, highlighting that it is important to incorporate information about particle characteristics as well as size when using these methods. Key Points: Ex situ studies typically find size to be a strong predictor of sinking velocity; strong correlations are rarely observed in situ howeverIncreased homogeneity of other particle characteristics ex situ (e.g., density, composition) are responsible for this discrepancyResults suggest importance of these other factors when predicting particle sinking velocities and fluxes using size‐scaling relationships [ABSTRACT FROM AUTHOR]

Substantial leaps in the understanding of quantum systems have been driven by exploring geometry, topology, dimensionality and interactions in ultracold atomic ensembles1–6. A system where atoms evolve while confined on an ellipsoidal surface represents a heretofore unexplored geometry and topology. Realizing an ultracold bubble—potentially Bose–Einstein condensed—relates to areas of interest including quantized-vortex flow constrained to a closed surface topology, collective modes and self-interference via bubble expansion7–17. Large ultracold bubbles, created by inflating smaller condensates, directly tie into Hubble-analogue expansion physics18–20. Here we report observations from the NASA Cold Atom Lab21 facility onboard the International Space Station of bubbles of ultracold atoms created using a radiofrequency-dressing protocol. We observe bubble configurations of varying size and initial temperature, and explore bubble thermodynamics, demonstrating substantial cooling associated with inflation. We achieve partial coverings of bubble traps greater than one millimetre in size with ultracold films of inferred few-micrometre thickness, and we observe the dynamics of shell structures projected into free-evolving harmonic confinement. The observations are among the first measurements made with ultracold atoms in space, using perpetual freefall to explore quantum systems that are prohibitively difficult to create on Earth. This work heralds future studies (in orbital microgravity) of the Bose–Einstein condensed bubble, the character of its excitations and the role of topology in its evolution.Bubbles of ultracold atoms have been created, observed and characterized at the NASA Cold Atom Lab onboard the International Space Station, made possible by the microgravity environment of the laboratory. [ABSTRACT FROM AUTHOR]

Phosphorous and nitrogen are electrically active species at the SiO2/SiC interface in SiC MOSFETs. We compare the concentration, chemical bonding, and etching behavior of P and N at the SiO2/SiC(0001) interface using photoemission, ion scattering, and secondary ion mass spectrometry. Both interfacial P and N are found to be resistant to buffered HF solution etching at the SiO2/SiC(0001) interface while both are completely removed from the SiO2/Si interface. The medium energy ion scattering results of etched phosphosilicate glass/SiC not only provide an accurate coverage but also indicate that both the passivating nitrogen and phosphorus are confined to within 0.5 nm of the interface. Angle resolved photoemission shows that P and N are likely situated in different chemical environments at the interface. We conclude that N is primarily bound to Si atoms at the interface while P is primarily bound to O and possibly to Si or C. Different interface passivating element coverages and bonding configurations on different SiC crystal faces are also discussed. The study provides insights into the mechanisms by which P and N passivate the SiO2/SiC(0001) interface and hence improve the performance of SiC MOSFETs. [ABSTRACT FROM AUTHOR]

The article presents the discussion on interpretations of the concepts assigning bizarre and unnatural denotations to the general concepts using in framing the hypotheses.

A Josephson junction (JJ) couples the supercurrent flowing between two weakly linked superconductors to the phase difference between them via a current-phase relation (CPR). While a sinusoidal CPR is expected for conventional junctions with insulating weak links, devices made from some exotic materials may give rise to unconventional CPRs and unusual Josephson effects. In this work, we present such a case: we investigate the proximity-induced superconductivity in SnTe nanowires by incorporating them as weak links in JJs and observe a deviation from the standard CPR. We report on indications of an unexpected breaking of time-reversal symmetry in these devices, detailing the unconventional characteristics that reveal this behavior. These include an asymmetric critical current in the DC Josephson effect, a prominent second harmonic in the AC Josephson effect, and a magnetic diffraction pattern with a minimum in critical current at zero magnetic field. The analysis examines how multiband effects and the experimentally visualized ferroelectric domain walls give rise to this behavior, giving insight into the Josephson effect in materials that possess ferroelectricity and/or multiband superconductivity. [ABSTRACT FROM AUTHOR]

Capacitance-voltage (C-V) and Deep-Level-Transient Spectroscopy (DLTS) measurements were performed on Metal-Oxide-Semiconductor (MOS) capacitors fabricated on 4H-SiC with the SiO2 layer grown by Sodium-Enhanced Oxidation. This technique has yielded 4H-SiC MOS transistors with record channel mobility, although with poor bias stability. The effects of the mobile positive charge on the C-V characteristics and DLTS spectra were investigated by applying a sequence of positive and negative bias-temperature stresses, which drifted the sodium ions toward and away from the SiO2/4H-SiC interface, respectively. Analytical modeling of the C-V curves shows that the drift of sodium ions in the SiO2 layer during the voltage sweep can explain the temperature dependence of the C-V curves. The effects of lateral fluctuations of the surface potential (due to a non-uniform charge distribution) on the inversion layer mobility of MOS transistors are discussed within a two-dimensional percolation model. [ABSTRACT FROM AUTHOR]

We report on the concentration, chemical bonding, and etching behavior of N at the SiC(0001)/SiO2 interface using photoemission, ion scattering, and computational modeling. For standard NO processing of a SiC MOSFET, a sub-monolayer of nitrogen is found in a thin inter-layer between the substrate and the gate oxide (SiO2). Photoemission shows one main nitrogen related core-level peak with two broad, higher energy satellites. Comparison to theory indicates that the main peak is assigned to nitrogen bound with three silicon neighbors, with second nearest neighbors including carbon, nitrogen, and oxygen atoms. Surprisingly, N remains at the surface after the oxide was completely etched by a buffered HF solution. This is in striking contrast to the behavior of Si(100) undergoing the same etching process. We conclude that N is bound directly to the substrate SiC, or incorporated within the first layers of SiC, as opposed to bonding within the oxide network. These observations provide insights into the chemistry and function of N as an interface passivating additive in SiC MOSFETs. [ABSTRACT FROM AUTHOR]

We report on optical band gap and valence electronic structure of two Eu2+-based perovskites, EuTiO3 and EuZrO3 as revealed by diffuse optical scattering, electron energy loss spectroscopy, and valence-band x-ray photoelectron spectroscopy. The data show good agreement with the first-principles studies in which the top of the valence band structure is formed by the narrow Eu 4f7 electron band. The O 2p band shows the features similar to those of the Ba(Sr)TiO3 perovskites except that it is shifted to higher binding energies. Appearance of the Eu2+ 4f7 band is a reason for narrowing of the optical band gap in the title compounds as compared to their Sr-based analogues. [ABSTRACT FROM AUTHOR]

Background and purpose: The purpose was to determine the test–retest reliability, practice effects, convergent validity and sensitivity to multiple sclerosis (MS) disability of neuroperformance subtests from the patient self‐administered Multiple Sclerosis Performance Test (MSPT) designed to assess low contrast vision (Contrast Sensitivity Test, CST), upper extremity motor function (Manual Dexterity Test, MDT) and lower extremity motor function (Walking Speed Test, WST) and to introduce the concept of regression‐based norms to aid clinical interpretation of performance scores using the MSPT cognition test (Processing Speed Test, PST) as an example. Methods: Substudy 1 assessed test–retest reliability, practice effects and convergent validity of the CST, MDT and WST in 30 MS patients and 30 healthy controls. Substudy 2 examined sensitivity to MS disability in over 600 MS patients as part of their routine clinic assessment. Substudy 3 compared performance on the PST in research volunteers and clinical samples. Results: The CST, MDT and WST were shown to be reliable, valid and sensitive to MS outcomes. Performance was comparable to technician‐administered testing. PST performance was poorer in the clinical sample compared with the research volunteer sample. Conclusions: The self‐administered MSPT neuroperformance modules produce reliable, objective metrics that can be used in clinical practice and support outcomes research. Published studies which require patient voluntary consent may underestimate the rate of cognitive dysfunction observed in a clinical setting. [ABSTRACT FROM AUTHOR]

Observations since 1998 have revealed that repeating earthquakes, and particularly small repeating earthquakes, occur less often than expected given their seismically derived slip and the regional fault slip rate. Here we test the hypothesis that small repeaters occur infrequently because they occur on fault segments or strands with low slip rates. We analyze the recurrence interval‐moment scaling of earthquake sequences near Parkfield, California. We find that closely spaced sequences, which likely occur on the same fault strand and respond to the same slip rate, follow a M013 scaling consistent with seismic slip rates while widely spaced sequences, which likely occur on different strands, follow a M00.17 scaling consistent with the previous counterintuitive observations. These results suggest that spatially varying slip rates could create the M00.17 recurrence interval scaling, though we cannot exclude other explanations. Plain Language Summary: We study repeating earthquakes, which repeatedly rupture part of a fault. Previous observations have shown that the cumulative slip in repeating earthquakes is smaller than the slip estimated from geological observations. This difference in slip means that the intervals between earthquakes are longer than expected, especially for smaller earthquakes. We examine whether the time between repeating earthquakes is long because small repeating earthquakes occur on a collection of shorter fault strands that exist within and contribute to the larger fault regime. We suggest that smaller earthquakes are more likely to occur on shorter fault strands and that shorter strands are likely to have lower slip rates than longer strands. Earthquake patches on shorter strands may be loaded slowly, so that the small earthquakes occur less often than expected. To test this possibility, we examine whether earthquakes that occur close together respond to the same slip rate. We find that closely spaced earthquakes do respond to the same slip rate, and widely spaced earthquakes respond to different slip rates. Our observations indicate that small repeating earthquakes may occur on short low slip rate fault strands. Key Points: We explore why small repeating earthquakes have surprisingly long recurrence intervalsFind that the scaling between recurrence interval and moment differs between closely and widely spaced earthquake sequencesSpacing‐dependent recurrence interval scaling could result from spatially variable or fault strand‐dependent slip rates [ABSTRACT FROM AUTHOR]

Metal-oxide-semiconductor (MOS) interfaces on n-type 4H and 6H-SiC annealed in nitric oxide (NO) for various times were electrically characterized by high-frequency capacitance-voltage and deep-level-transient spectroscopy (DLTS) measurements. Different types of traps were distinguished by DLTS based on the energy-resolved DLTS spectra and comparing DLTS spectra from the two polytypes. Oxide traps, found at much higher densities in the larger bandgap 4H-SiC, are reduced by NO annealing, and their capture behavior is analytically modeled with a tunneling-dependent capture rate. An interface trap distribution is found in 6H-SiC MOS centered at 0.5 eV below the conduction band. Near interface traps in the SiC within 0.1 eV below the conduction band edge, detected at equal concentrations in both polytypes, are not passivated by NO annealing. [ABSTRACT FROM AUTHOR]

Oxidation of SiC with the incorporation of Na in the gate oxide was recently found to lead to significantly enhanced electron mobilities in the SiC inversion layer but the underlying mechanism has remained elusive. Here, we report a combination of density functional first-principles calculations and experiments. The new findings demonstrate that neutral Na is essentially a spectator impurity that occupies near interfacial interstitial sites and does not interact with the interface or with interfacial defects. Na ions, however, introduce an effective mass hydrogenic impurity band at the edge of the SiC conduction band that can account for the observed effects. [ABSTRACT FROM AUTHOR]

Nitridation of the SiO2/SiC interface yields a reduction in interface state density, immunity to electron injection, as well as increased hole trapping. It is shown that the accumulation of nitrogen at the oxide/semiconductor interface is solely responsible for these three effects. The evolution of the density of interface states, electron traps, and hole traps is measured in metal-oxide-semiconductor capacitors as a function of the nitrogen content which is varied by adjusting the gate oxide NO annealing time. A rate equation is derived to model the change in the interface state density, observed at various energy levels, in terms of nitrogen binding cross-sections. While the generation of acceptor interface states upon electron injection is suppressed after minimum N incorporation, the density of oxide hole traps appears to scale linearly with the amount of nitrogen. The origin and the properties of the N-induced hole traps resembles those of the defects responsible for enhanced negative bias temperature instability observed in nitrided silicon devices. It is proposed that the binding of nitrogen is not exclusively driven by the passivation of defects at the semiconductor surface but also results in the formation of a silicon oxynitride layer redefining the interface. [ABSTRACT FROM AUTHOR]

Nitrogen incorporation at the SiO2/SiC interface via high temperature nitric oxide annealing leads to the passivation of electrically active interface defects, yielding improved inversion mobility in the semiconductor. However, we find that such nitrided oxides can possess a larger density of hole traps than as-grown oxides, which is detrimental to the reliability of devices (e.g., can lead to large threshold voltage instabilities and to accelerated failure). Three different charge injection techniques are used to characterize this phenomenon in metal–oxide–semiconductor structures: x-ray irradiation, internal photoemission and Fowler–Nordheim tunneling. Some nitrogen-based atomic configurations that could act as hole traps in nitrided SiO2 are discussed based on first-principles density functional calculations. [ABSTRACT FROM AUTHOR]

Postoxidation annealing in nitric oxide (NO) results in a significant reduction of electronic states at SiO2/4H-SiC interfaces. Measurements of electron trapping dynamics at interface states in both thermally oxidized and NO annealed SiO2/4H-SiC interfaces were performed using constant-capacitance deep level transient spectroscopy (CCDLTS) and double-CCDLTS. We show that the interface state density in as-oxidized samples consists of overlapping distributions of electron traps that have distinctly different capture cross sections. The dominant trap distributions, centered at Ec-0.24 eV with σ∼7×10-19 cm2, and at Ec-0.46 eV with σ∼4×10-17 cm2 are passivated by NO annealing. The remaining interface states all have capture cross sections in the range 10-19-10-21 cm2. [ABSTRACT FROM AUTHOR]

Dry oxidations between 0.25 and 4 atm at 1150 °C are used to characterize the pressure dependence of the growth kinetics of SiO2 along three orientations of the 4H-SiC polytype. The growth curves are studied using the Deal-Grove model. The extracted linear and parabolic constants are found to scale linearly with the pressure up to 2 atm. However, the data indicate that the (0001) Si-face exhibits a retarded growth rate above 2 atm. It is also found that, like Si, there is a critical oxide thickness below which the linear-parabolic model cannot be applied. This value is found to be between 36 and 40 nm for SiO2 on 4H-SiC, and is apparently independent of the crystal orientation and oxidation pressure. The extracted critical thickness and its properties are similar to what is observed on Si, suggesting that the fast growth regime is dictated by the nature of the oxide. Finally, it is shown that the density of interface states (Dit) on the (0001) Si-face is not reduced by faster oxide growth rates within the monitored energy window. [ABSTRACT FROM AUTHOR]

Postgrowth annealing was carried out to investigate the photoluminescence of zinc oxide (ZnO) nanorods synthesized using a thermal chemical vapor deposition method. The observed change in photoluminescence after the annealing processes strongly suggests that positively charged impurity ions or interstitial Zn ions are the recombination centers for green luminescence observed in the present sample. A model based on the interplay between the band bending at the surface and the migration of positively charged impurity ions or Zn ions was proposed, which satisfactorily explains the observed photoluminescence. [ABSTRACT FROM AUTHOR]

We report on the observation of ultraviolet lasing in optically pumped ZnO nanonails synthesized by thermal chemical vapor deposition method. The lasing threshold was found to be 17 MW cm-2. Very sharp emission peaks (full width at half maximum of 0.08 nm) were observed in the emission spectrum, indicating a high Q factor of the cavity formed by the hexagonally shaped nanonail head. The analysis of the lasing spectra strongly suggests the whispering gallery mode lasing from a hexagonally shaped head of the single ZnO nanonail. [ABSTRACT FROM AUTHOR]

Interface trap passivation at the SiO2/carbon-terminated (0001) face of 4H-SiC utilizing nitridation and hydrogenation has been evaluated. The SiO2/SiC interface, created by dry thermal oxidation on the C face, shows appreciably higher interface state density near the conduction band compared to the (0001) Si face. A postoxidation anneal in nitric oxide followed by a postmetallization anneal in hydrogen results in dramatic reduction of the trap density by over an order of magnitude near the conduction band. The electrical measurements have been correlated with the interfacial chemistry. [ABSTRACT FROM AUTHOR]

High-resolution elemental profiles were obtained from SiO2(N) /4H-SiC structures by spatially resolved electron energy-loss spectroscopy (EELS) performed in the scanning transmission electron microscopy mode. The results show that following annealing in NO, N was exclusively incorporated within ~1 nm of the SiO2(N) /4H-SiC interface. Mean interfacial nitrogen areal densities measured by EELS were ~(1.0±0.2)×1015 cm-2 in carbon-face samples and (0.35±0.13)×1015 cm-2 in Si-face samples; these results are consistent with nuclear reaction analysis measurements. Some of the interface regions in the C-face samples also showed excess carbon that was not removed by the NO annealing process, in contrast with previous results on Si-face samples. [ABSTRACT FROM AUTHOR]

Nitrogen incorporation at the SiO2/SiC interface due to annealing in NO is measured and shown to be a strong function of crystal face. The annealing process involves two major solid-state chemical reactions: nitrogen uptake at the interface and N loss associated with second-order oxidation. An ad hoc kinetics model explains the experimental observations of anisotropy and nitrogen saturation. [ABSTRACT FROM AUTHOR]

GaN template layer strain effects on the growth of InGaN/GaN light emitting diodes devices were investigated. Seven-period InGaN/GaN multiple quantum well structures (MQW) were deposited on 5 and 15 μm GaN template layers. It was found that the electroluminescence emission of the 15 μm device was redshifted by approximately 132 meV. Triple-axis x-ray diffraction and cross-sectional transmission electron microscopy show that the 15 μm template layer device was virtually unstrained while the 5 μm layer experienced tensile strain. Dynamic secondary ion mass spectrometry depth profiles show that the 15 μm template layer device had an average indium concentration of 11% higher than that of the 5 μm template layer device even though the MQW structures were deposited during the same growth run. It was also found that the 15 μm layer device had a higher average growth rate than the 5 μm template layer device. This difference in indium concentration and growth rate was due to changes in thermodynamic limitations caused by strain differences in the template layers. [ABSTRACT FROM AUTHOR]

A modified Deal Grove model for the oxidation of 4H-SiC is presented, which includes the removal of the carbon species. The model is applied to data on the oxidation rates for the (0001) Si, (0001) C, and (1120) a faces, which are performed in 1 atm dry oxygen and in the temperature range 950–1150 °C. Analysis within the model provides a physical explanation for the large crystal-face dependent oxidation rates observed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The relationship between nitrogen content and interface trap density (D[sub it]) in SiO[sub 2]/4H-SiC near the conduction band has been quantitatively determined. Nitridation using NO significantly reduces D[sub it] near the conduction band, but the effect saturates after ≈2.5 × 10[sup 14] cm[sup -2] of nitrogen. These results are consistent with a model of the interface in which defects such as carbon clusters or silicon suboxide states produce traps with energies corresponding to the sizes of the defects. Nitrogen passivation results in the dissolution of the defects, which then lowers the energies of the traps in the band gap. [ABSTRACT FROM AUTHOR]

The kinetics of nitrogen incorporation in SiO[sub 2]/4H-SiC using NO are presented. Samples were annealed in NO at pressures of 100 Torr and 1 atm, at temperatures from 1050 to 1175 °C, and for times from 0.5 to 6 h. Annealing in NO incorporates ∼10[sup 14] cm[sup -2] of nitrogen at the SiO[sub 2]/SiC interface. The nitrogen content initially increases with time and temperature, but nitrogen is removed at later times at temperatures above 1050 °C. This nitrogen removal, and the associated oxide growth in the SiC substrate, is caused by O[sub 2] formed by the thermal decomposition of NO. Eventually, the nitridation and oxidation reactions reach equilibrium, and the nitrogen content saturates as the oxide thickness increases. [ABSTRACT FROM AUTHOR]

The article presents the discussion on the book 'The Metaphysics of Representation' requiring a specification of alien psychological structure and alien rationality.

Abstract: Assessments of impacts of future climate change on widely grown sugarcane varieties can guide decision‐making and help ensure the economic stability of numerous rural households. This study assessed the potential impact of future climatic change on sugarcane grown under dryland conditions in Mexico and identified key climate factors influencing yield. The Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) model was used to simulate sugarcane growth and yield under current and future climate conditions. Management, soil and climate data from farm sites in Jalisco (Pacific Mexico) and San Luis Potosi (Northeastern Mexico) were used to simulate baseline yields. Baseline climate was developed with 30‐year historical data from weather stations close to the sites. Future climate for three decadal periods (2021–2050) was constructed by adding forecasted climate values from downscaled outputs of global circulation models to baseline values. Climate change impacts were assessed by comparing baseline yields with those in future decades under the A2 scenario. Results indicate positive impacts of future climate change on sugarcane yields in the two regions, with increases of 1%–13% (0.6–8.0 Mg/ha). As seen in the multiple correlation analysis, evapotranspiration explains 77% of the future sugarcane yield in the Pacific Region, while evapotranspiration and number of water and temperature stress days account for 97% of the future yield in the Northeastern Region. The midsummer drought (canicula) in the Pacific Region is expected to be more intense and will reduce above‐ground biomass by 5%–13% (0.5–1.7 Mg/ha) in July–August. Harvest may be advanced by 1–2 months in the two regions to achieve increases in yield and avoid early flowering that could cause sucrose loss of 0.49 Mg ha−1 month−1. Integrating the simulation of pest and diseases under climate change in crop modelling may help fine‐tune yield forecasting. [ABSTRACT FROM AUTHOR]

A source of thermal, ground-state atomic oxygen has been used to expose thin copper films at a flux of 1.4×1017 atoms/cm2 s for times up to 50 min for each of five temperatures between 140 and 200 °C. Rutherford backscattering spectroscopy was used to characterize the oxide formed during exposure. The observations are consistent with the oxide phase Cu2O. The time dependence and the temperature dependence of the oxide layer thickness can be described using oxide film growth theory based on rate limitation by diffusion. Within the time and temperature ranges of this study, the growth of the oxide layers is well described by the equation L(T,t)=3.6×108 exp(-1.1/2kBT)t12, where L, T, and t are measured in angstroms, degrees Kelvin, and minutes, respectively. The deduced activation energy is 1.10±0.15 eV, with the attendant oxidation rate being greater than that for the corresponding reaction in molecular oxygen. [ABSTRACT FROM AUTHOR]

Discusses a study on phase determination and spatial distribution of ion-beam mixing of tin on iron. Application of tin to the surface of iron is known to retard high-temperature oxidation; Iron-tin specimen after completion of sample preparation procedures; Iron-tin specimen treatments.

Discusses the radiation damage caused by heavier [sup4]He[sup+] ions. Significance of capacitance-voltage measurements; Development of a compensated region in the vicinity of oxide-semiconductor interface; Equivalence circuits of metal-oxide-n-p-n structures with thin oxide layer.

Objectives: To assess five-year local control and ultimate local control rates of patients treated for locally advanced T3–4 glottic carcinoma with surgery only, radiotherapy only, or surgery plus radiotherapy. Cancer-specific survival, overall survival and rates of malignancy development were also assessed. Methods: A retrospective review was conducted on patients from 1967 to 2015, with analysis of local control, ultimate local control, overall survival and cancer-specific survival performed using Kaplan–Meier and Cox regression. Results: Of 169 eligible patients, the majority (59 per cent) were treated with surgery plus radiotherapy, with laryngectomy being the most common surgical procedure. Local control and ultimate local control rates were higher with surgery only (94.1 per cent) and surgery plus radiotherapy (87.9 and 86.8 per cent respectively), compared to radiotherapy only (46.8 and 52.4 per cent) (both p < 0.001). Cancer-specific survival, overall survival and malignancy development did not differ between groups. Conclusion: Surgery, with or without radiotherapy, offers significantly higher five-year local control and ultimate local control for patients with advanced glottic carcinoma, compared to radiotherapy only. [ABSTRACT FROM AUTHOR]

Toheroa (Paphies ventricosa) were formerly abundant on west and south-facing New Zealand surf beaches. Harvesting of this surf clam was intense during the early to mid-1900s, and populations declined to levels where harvesting was no longer viable. Despite having now been protected for 35-45 years, toheroa have failed to recover. This paper reviews the history of human interactions with toheroa and our understanding of their ecology, with a view to identifying knowledge requirements for management and restoration. Historical and legal documents pertaining to the use of marine resources are reviewed and scientific understanding compared with customary and local knowledge. We consider the factors that may be preventing toheroa recovery and make recommendations for research into life history, habitat requirements and the ecological consequences of changing land use. Management options are suggested to address the effects of vehicle use on beaches, poaching and the failings of the customary harvest system. [ABSTRACT FROM AUTHOR]

Investigates specific contact resistance measured at elevated temperatures for nickel ohmic contacts to hydrogen-silicon carbide. Application of the linear transmission line method; Fabrication of a van der Pauw pattern; Findings of Auger analysis of the nickel film.

This study aimed to quantify the amount of nitrogen (N) mineralized from the organic fraction of farm manures under field conditions. Nine different farm manures were stripped of their ammonium-N content prior to soil incorporation and establishment of ryegrass at two sites in England. Grass N uptake and nitrate-N leaching were measured for five consecutive seasons and compared with an untreated control, with the sum of N uptake + leaching (net of the control) used as an estimate of the amount of organic N mineralized from the applied manures. The amount mineralized was related to thermal time (cumulative day degrees above 5 °C - CDD), with two distinct phases - an initial phase up to 2300 CDD ( c.18 months under UK climatic conditions) where mineralization proceeded at rates ranging between 0.005 and 0.027%mineralized/ CDD and a slower phase at >2300 CDD, where rates were negligible at <0.001%mineralized/ CDD. There was no difference between soil types, both being light-textured (<20% clay), but there were differences between manure types depending on the manure C: organic N ratios. For pig slurry and layer manure (C:organic N = 9-12:1), up to 70% of the organic N was mineralized, compared to 10-30% mineralization from the cattle slurry and straw-based farmyard manures- FYMs (C:organic N = 10-21:1).The relationships derived provide a useful tool for predicting both the amount and timing of manure N release, with important implications for both crop N uptake and leaching risk. [ABSTRACT FROM AUTHOR]

In November 2016, the Council for International Organizations of Medical Sciences (CIOMS) published its revised International Ethical Guidelines for Health-related Research Involving Humans. In relation to earlier versions, the scope of the new guidelines has been expanded to include public-health research. While successful to some extent, the document does not take into sufficient account the differences between public-health research and other types of health research. It is silent on some issues of importance to public-health research, such as its definition, health inequities and novel research methodologies. Its treatment of some other issues, including the need for researchethics committee approval, consent, community involvement and dissemination of research results, are deficient in some respects. The guidelines that are particularly applicable to and useful for public-health research deal with social value, the health needs of communities and populations, community engagement, disasters and disease outbreaks, cluster randomised trials and data sharing. Much further development of the foundations and applications of public-health research ethics is needed to inform future revisions of the guidelines and of other international and national research-ethics documents. [ABSTRACT FROM AUTHOR]

The effects of soil erosion and sedimentation are important for natural resources conservation planning. However, although tremendous resources have been invested in developing more erosion models, the prevailing modeling studies are relying on a single model due to various reasons. The Agricultural Policy Environmental Extender (APEX) provides multiple water erosion equations. This study tests and evaluates the Bayesian model averaging (BMA) scheme on sediment predictions based on four water erosion methods in the APEX model using data from two watersheds. The APEX hydrology and soil erosion and sedimentation components were calibrated simultaneously using the APEX autocalibration tool APEX-CUTE. The BMA scheme is employed to obtain consensus predictions by weighing individual predictions based on their probabilistic likelihood measures. Simulated monthly flow was satisfactory for both the calibration and validation periods, with BMA resulting in Nash--Sutcliffe efficiency (NSE) values from 0.56 to 0.87 and percent bias (PBIAS) within ±17%. No individual soil erosion method in APEX is consistently outperformed other method over the entire sediment yield regimes at both watersheds. The BMA scheme led to improved predictions compared with individual methods and resulted in satisfactory performance statistics (NSE from 0.55 to 0.88) for both the calibration and validation periods based on the optimal solutions. BMA also led to relatively higher Brier scores and narrower prediction bounds than individual methods. The methodology is unrestrictedly general and can be applied to any other combination of models in the environmental sciences. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present study was to analyse the mineralization pattern of enamel and dentin in patients affected by X-linked hypophosphatemic rickets (XLHR) using micro-CT (µCT), and to associate enamel and dentin mineralization in primary and permanent teeth with tooth position, gender and the presence/absence of this disease. Methods: 19 teeth were collected from 5 individuals from the same family, 1 non-affected by XLHR and 4 affected by XLHR. Gender, age, tooth position (anterior/posterior) and tooth type (deciduous/permanent) were recorded for each patient. Following collection, teeth were placed in 0.1% thymol solution until µCT scan. Projection images were reconstructed and analysed. A plot profile describing the greyscale distance relationship in µCT images was achieved through a line bisecting each tooth in a region with the presence of enamel and dentin. The enamel and dentin mineralization densities were measured and compared. Univariate ANOVA and post hoc Tukey tests were used for all comparisons. Results: Teeth of all affected patients presented dentin with a different mineralization pattern compared with the teeth of healthy patients with dentin defects observed next to the pulp chambers. Highly significant differences were found for gray values between anterior and posterior teeth (p?