Dynamic and thermal analysis of high speed tapered roller bearings under combined loading

The development of a computer program capable of predicting the thermal and kinetic performance of high-speed tapered roller bearings operating with fluid lubrication under applied axial, radial and moment loading (five degrees of freedom) is detailed. Various methods of applying lubrication can be considered as well as changes in bearing internal geometry which occur as the bearing is brought to operating speeds, loads and temperatures

Chorioretinitis And Detached Retina as Post-Distemper Lesions in the Canine

In the canine species there are many causes of chorioretinitis and detachment of the retina. Among these are: fungal infections such as Blastomycosis and Cocidiodomicosis; invasion by Toxoplasma organisms; trauma to structures of the eye with subsequent hemorrhage, infection or rupture of the vitreous; tumors of the choroid or retina; parasitic larval migrans such as Toxacara vanis; progressive hereditary diseases; and those of unknown etiology

AsS2Cl - An arsenic(V) compound? Formation, stability and structure of gaseous AsSCl and AsS2Cl - A combined experimental and theoretical study

By reaction of solid As4S4 with gaseous Cl2 at a temperature of 410 K gaseous AsSCl and AsS2Cl are formed. Unexpectedly in AsS2Cl the arsenic is not of formal oxidation state +V but +III: the molecular structure of AsS2Cl is arranged as a 1-chloro-dithia-arsirane and comprises an hitherto unknown AsS2 three-membered ring. Thermodynamic data on AsSCl and AsS2Cl are obtained by mass spectrometry (MS). The experimental data are extended and confirmed by ab initio quantum chemical calculations (QC). The following values are given: ΔfH0298(AsSCl) = −5.2 kJ mol−1 (MS), ΔfH0298(AsSCl) = 1.7 kJ mol−1 (QC), S0298(AsSCl) = 296.9 J K−1 mol−1 (QC) and cp0T(AsSCl) = 55.77 + 3.97 × 10−3T − 4.38 × 105T−2 − 1.83 × 10−6T2 and ΔfH0298(AsS2Cl) = −39.0 kJ mol−1 (MS), ΔfH0298(AsS2Cl) = −20.2 kJ mol−1 (QC), S0298(AsS2Cl) = 321.3 J K−1 mol−1 (QC) and cp0T(AsS2Cl) = 80.05 + 5.09 × 10−3T − 7.61 × 105T−2 − 2.35 × 10−6T2 (298.15 K < T < 1000 K) (QC). The ionization energies are determined (IP(AsSCl) = 10.5, IP(AsS2Cl) = 10.2 eV). The IR spectrum of AsSCl is detected by means of matrix isolation spectroscopy. The estimated force constant f(As[double bond, length as m-dash]S) = 4.47 mdyn·Å−1 gives rise to an As[double bond, length as m-dash]S double bond

Silicon and oxygen self diffusion in enstatite polycrystals: the Milke et al. (2001) rim growth experiments revisited

Milke et al. (Contrib Mineral Petrol 142:15-26, 2001) studied the diffusion of Si, Mg and O in synthetic polycrystalline enstatite reaction rims. The reaction rims were grown at 1,000°C and 1GPa at the contacts between forsterite grains with normal isotopic compositions and a quartz matrix extremely enriched in 18O and 29Si. The enstatite reaction rim grew from the original quartz-forsterite interface in both directions producing an inner portion, which replaced forsterite and an outer portion, which replaced quartz. Here we present new support for this statement, as the two portions of the rim are clearly distinguished based on crystal orientation mapping using electron backscatter diffraction (EBSD). Milke et al. (Contrib Mineral Petrol 142:15-26, 2001) used the formalism of LeClaire (J Appl Phys 14:351-356, 1963) to derive the coefficient of silicon grain boundary diffusion from stable isotope profiles across the reaction rims. LeClaire's formalism is designed for grain boundary tracer diffusion into an infinite half space with fixed geometry. A fixed geometry is an undesired limitation in the context of rim growth. We suggest an alternative model, which accounts for simultaneous layer growth and superimposed silicon and oxygen self diffusion. The effective silicon bulk diffusivity obtained from our model is approximately equal within both portions of the enstatite reaction rim: D Si,En eff =1.0-4.3×10−16m2s−1. The effective oxygen diffusion is relatively slow in the inner portion of the reaction rim, D O,En eff =0.8-1.4×10−16m2s−1, and comparatively fast, D O,En eff =5.9-11.6×10−16m2s−1, in its outer portion. Microstructural evidence suggests that transient porosity and small amounts of fluid were concentrated at the quartz-enstatite interface during rim growth. This leads us to suspect that the presence of an aqueous fluid accelerated oxygen diffusion in the outer portion of the reaction rim. In contrast, silica diffusion does not appear to have been affected by the spatial variation in the availability of an aqueous flui

Peer Review Panel: A New Zealand approach to regulatory compliance of landfills

New Zealand is increasingly using a Peer Review Panel (PRP) system for regulatory compliance of complex and contentious environmental infrastructure facilities, such as landfills. The PRP is a set of experts who serve as an advisor to the operator and the regulator, and are responsible to both parties for independent assessments. The PRP for the Kate Valley landfill facility is presented as a case study in the motivation for, and operation of, a PRP. The use of the PRP arises partly from the effects-based environmental legislation in New Zealand, which leads to a lack of standardization in construction/operation and unique permit conditions at each site. The PRP meets with operators on a regular basis, conducts site visits, receives relevant documentation, and prepares an annual report for regulatory authorities. The PRP is able to examine and discuss safety, financial, and operational issues with the operators while maintaining confidentiality. This allows for open discussions of these issues where they might impact on environmental performance. The PRP also assists operators by providing them with technical information and experience from outside the operator’s business environment. The PRP is a valuable option for regulatory bodies and project proponents to consider when developing permits for any one-off, complex facility with potentially large environmental impacts, and with great public concern

Erioflorin stabilizes the tumor suppressor Pdcd4 by inhibiting its interaction with the E3-ligase β-TrCP1

Loss of the tumor suppressor Pdcd4 was reported for various tumor entities and proposed as a prognostic marker in tumorigenesis. We previously characterized decreased Pdcd4 protein stability in response to mitogenic stimuli, which resulted from p70S6K1-dependent protein phosphorylation, β-TrCP1-mediated ubiquitination, and proteasomal destruction. Following high-throughput screening of natural product extract libraries using a luciferase-based reporter assay to monitor phosphorylation-dependent proteasomal degradation of the tumor suppressor Pdcd4, we succeeded in showing that a crude extract from Eriophyllum lanatum stabilized Pdcd4 from TPA-induced degradation. Erioflorin was identified as the active component and inhibited not only degradation of the Pdcd4-luciferase-based reporter but also of endogenous Pdcd4 at low micromolar concentrations. Mechanistically, erioflorin interfered with the interaction between the E3-ubiquitin ligase β-TrCP1 and Pdcd4 in cell culture and in in vitro binding assays, consequently decreasing ubiquitination and degradation of Pdcd4. Interestingly, while erioflorin stabilized additional β-TrCP-targets (such as IκBα and β-catenin), it did not prevent the degradation of targets of other E3-ubiquitin ligases such as p21 (a Skp2-target) and HIF-1α (a pVHL-target), implying selectivity for β-TrCP. Moreover, erioflorin inhibited the tumor-associated activity of known Pdcd4- and IκBα-regulated αtranscription factors, that is, AP-1 and NF-κB, altered cell cycle progression and suppressed proliferation of various cancer cell lines. Our studies succeeded in identifying erioflorin as a novel Pdcd4 stabilizer that inhibits the interaction of Pdcd4 with the E3-ubiquitin ligase β-TrCP1. Inhibition of E3-ligase/target-protein interactions may offer the possibility to target degradation of specific proteins only as compared to general proteasome inhibition

Dissecting the knee - Air shower measurements with KASCADE

Recent results of the KASCADE air shower experiment are presented in order to shed some light on the astrophysics of cosmic rays in the region of the knee in the energy spectrum. The results include investigations of high-energy interactions in the atmosphere, the analysis of the arrival directions of cosmic rays, the determination of the mean logarithmic mass, and the unfolding of energy spectra for elemental groups

Testing the proposed link between cosmic rays and cloud cover

A decrease in the globally averaged low level cloud cover, deduced from the ISCCP infra red data, as the cosmic ray intensity decreased during the solar cycle 22 was observed by two groups. The groups went on to hypothesise that the decrease in ionization due to cosmic rays causes the decrease in cloud cover, thereby explaining a large part of the presently observed global warming. We have examined this hypothesis to look for evidence to corroborate it. None has been found and so our conclusions are to doubt it. From the absence of corroborative evidence, we estimate that less than 23%, at the 95% confidence level, of the 11-year cycle change in the globally averaged cloud cover observed in solar cycle 22 is due to the change in the rate of ionization from the solar modulation of cosmic rays

Effects of CO\u3csub\u3e2\u3c/sub\u3e on Growth Rate, C:N:P, and Fatty Acid Composition of Seven Marine Phytoplankton Species

Carbon dioxide (CO2) is the primary substrate for photosynthesis by the phytoplankton that form the base of the marine food web and mediate biogeochemical cycling of C and nutrient elements. Specific growth rate and elemental composition (C:N:P) were characterized for 7 cosmopolitan coastal and oceanic phytoplankton species (5 diatoms and 2 chlorophytes) using low density, nutrient-replete, semi-continuous culture experiments in which CO2 was manipulated to 4 levels ranging from post-bloom/glacial maxima (ppm) to geological maxima levels (\u3e2900 ppm). Specific growth rates at high CO2 were from 19 to 60% higher than in low CO2 treatments in 4 species and 44% lower in 1 species; there was no significant change in 2 species. Higher CO2 availability also resulted in elevated C:P and N:P molar ratios in Thalassiosira pseudonana (~60 to 90% higher), lower C:P and N:P molar ratios in 3 species (~20 to 50% lower), and no change in 3 species. Carbonate system-driven changes in growth rate did not necessarily result in changes in elemental composition, or vice versa. In a subset of 4 species for which fatty acid composition was examined, elevated CO2 did not affect the contribution of polyunsaturated fatty acids to total fatty acids significantly. These species show relatively little sensitivity between present day CO2 and predicted ocean acidification scenarios (year 2100). The results, however, demonstrate that CO2 availability at environmentally and geologically relevant scales can result in large changes in phytoplankton physiology, with potentially large feedbacks to ocean biogeochemical cycles and ecosystem structure