Effect of filtration on rolling-element-bearing life in contaminated lubricant environment

Fatigue tests were conducted on groups of 65 millimeter-bore ball bearings under four levels of filtration with and without a contaminated MIL-L-23699 lubricant. The baseline series used noncontaminated oil with 49 micron absolute filtration. In the remaining tests contaminants of the composition found in aircraft engine filters were injected into the filter's supply line at a constant rate of 125 milligrams per bearing-hour. The test filters had absolute particle removal ratings of 3, 30, 49, and 105 microns (0.45, 10, 30, and 70 microns nominal), respectively. Bearings were tested at 15,000 rpm under 4580 newtons radial load. Bearing life and running tract condition generally improved with finer filtration. The 3 and 30 micron filter bearings in a contaminated lubricant had statistically equivalent lives, approaching those from the baseline tests. The experimental lives of 49 micron bearings were approximately half the baseline bearing's lives. Bearings tested with the 105 micron filter experienced wear failures. The degree of surface distress, weight loss, and probable failure mode were found to be dependent on filtration level, with finer filtration being clearly beneficial

Tunable fibre-coupled multiphoton microscopy with a negative curvature fibre

Negative curvature fibre (NCF) guides light in its core by inhibiting the coupling of core and cladding modes. In this work, an NCF was designed and fabricated to transmit ultrashort optical pulses for multiphoton microscopy with low group velocity dispersion (GVD) at 800 nm. Its attenuation was measured to be <0.3 dB m(-1) over the range 600-850 nm and the GVD was -180 ± 70 fs(2)  m(-1) at 800 nm. Using an average fibre output power of ∼20 mW and pulse repetition rate of 80 MHz, the NCF enabled pulses with a duration of <200 fs to be transmitted through a length of 1.5 m of fibre over a tuning range of 180 nm without the need for dispersion compensation. In a 4 m fibre, temporal and spectral pulse widths were maintained to within 10% of low power values up to the maximum fibre output power achievable with the laser system used of 278 mW at 700 nm, 808 mW at 800 nm and 420 mW at 860 nm. When coupled to a multiphoton microscope, it enabled imaging of ex vivo tissue using excitation wavelengths from 740 nm to 860 nm without any need for adjustments to the set-up

Self-Assessment and Planned Change of Placement and Career Services Center

In the 1990s, college and university career services and placement units face many challenges which may influence their success including (a) increased budgetary constraints, (b) changing student demographics, (c) increased availability of computer technologies, (d) new service delivery models, and (e) changing employer recruitment practices. In an effort to address these issues and examine its role within the university (Roth, 1994), the Placement and Career Information Center (PCIC) at Central Michigan University undertook a program of applied research, self-assessment and planned change. The purpose of this article is to briefly report our experiences in conducting this program of applied research. The assessment strategy is presented in the first part of this report. Next, the methods used to collect data and assessment, sampling procedures and response rates are described. Following this, highlights of the assessment results are presented including a summary of some changes already made and those planned for the future. The results of this study are presented in detail in Adams, et at. (1994)

Adherence to the paediatric immunisation schedule in England

Both adequate coverage and adherence to paediatric immunisation schedules are required for optimal protection against vaccine preventable diseases. We studied the timeliness of routine paediatric vaccinations according to the NHS's immunisation schedule and potential factors of schedule adherence. Immunisation data was obtained from the Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC). We collected vaccine types, doses, and dates for all routine paediatric vaccines between 2008 and 2018: DTaP/IPV/Hib/HepB, DTaP/IPV/Hib, DTaP/IPV, dTaP/IPV, Td/IPV, MMR, PCV, MenB, MenC, MenACWY, Hib/MenC, RV, HPV. Adherence to the immunisation schedule was calculated for each vaccine and dose. Differences in adherence between genders, NHS regions, and IMD quintiles were analysed. Our study included 6'257'828 vaccinations in 1'005'827 children. Seventy-five percent of first doses were administered within one (for vaccines scheduled in the first year of life) or two months (for vaccines scheduled later in life) following the recommended age, 19% too late and 6% too early. About half of the subsequent doses were given timely. The time between first and second doses was too short for 36% of vaccinations while 13% of second doses were administered too long after the first dose. Third doses were administered timely for 45%, too short for 37%, and too long for 18% of vaccinations. Differences in immunisation schedule adherence between girls and boys were negligible, except for HPV, and differences between the four main NHS regions were small. Overall, immunisation schedule adherence improved slightly with decreasing deprivation according to the Index of Multiple Deprivation. Efforts are required to improve the timeliness of paediatric vaccinations and to assure adequate protection against vaccine preventable diseases. We propose developing a compound measure combining coverage and adherence to provide a better indication of the protection against vaccine preventable diseases in a community

Modification of classical electron transport due to collisions between electrons and fast ions

A Fokker-Planck model for the interaction of fast ions with the thermal electrons in a quasi-neutral plasma is developed. When the fast ion population has a net flux (i.e. the distribution of the fast ions is anisotropic in velocity space) the electron distribution function is significantly perturbed from Maxwellian by collisions with the fast ions, even if the fast ion density is orders of magnitude smaller than the electron density. The Fokker-Planck model is used to derive classical electron transport equations (a generalized Ohm's law and a heat flow equation) that include the effects of the electron-fast ion collisions. It is found that these collisions result in a current term in the transport equations which can be significant even when total current is zero. The new transport equations are analyzed in the context of a number of scenarios including $\alpha$ particle heating in ICF and MIF plasmas and ion beam heating of dense plasmas

Ammonia emissions from cattle urine and dung excreted on pasture

Twelve cattle were kept for three days in a circular area of 16 m radius on short pasture and fed with freshly-cut pasture. Ammonia (NH&lt;sub&gt;3&lt;/sub&gt;) emissions from the urine and dung excreted by the cattle were measured with a micrometeorological mass-balance method, during the cattle presence and for 10 subsequent days. Daily-integrated emission rates peaked on Day 3 of the experiment (last day of cattle presence) and declined steadily for five days thereafter. Urine patches were the dominant sources for these emissions. On Day 9, a secondary emissions peak occurred, with dung pats likely to be the main sources. This interpretation is based on simultaneous observations of the pH evolution in urine patches and dung pats created next to the circular plot. Feed and dung samples were analysed to estimate the amounts of nitrogen (N) ingested and excreted. Total N volatilised as NH&lt;sub&gt;3&lt;/sub&gt; was 19.8 (± 0.9)% of N intake and 22.4 (± 1.3)% of N excreted. The bimodal shape of the emissions time series allowed to infer separate estimates for volatilisation from urine and dung, respectively, with the result that urine accounted for 88.6 (± 2.6)% of the total NH&lt;sub&gt;3&lt;/sub&gt; emissions. The emissions from urine represented 25.5 (± 2.0)% of the excreted urine-N, while the emissions from dung amounted to 11.6 (± 2.7)% of the deposited dung-N. Emissions from dung may have continued after Day 13 but were not resolved by the measurement technique. A simple resistance model shows that the magnitude of the emissions from dung is controlled by the resistance of the dung crust

Fibre-coupled multiphoton microscope with adaptive motion compensation

To address the challenge of sample motion during in vivo imaging, we present a fibre-coupled multiphoton microscope with active axial motion compensation. The position of the sample surface is measured using optical coherence tomography and fed back to a piezo actuator that adjusts the axial location of the objective to compensate for sample motion. We characterise the system’s performance and demonstrate that it can compensate for axial sample velocities up to 700 µm/s. Finally we illustrate the impact of motion compensation when imaging multiphoton excited autofluorescence in ex vivo mouse skin

11 beta-hydroxysteroid dehydrogenase type 1 regulates glucocorticoid-induced insulin resistance in skeletal muscle

OBJECTIVE: Glucocorticoid excess is characterized by increased adiposity, skeletal myopathy, and insulin resistance, but the precise molecular mechanisms are unknown. Within skeletal muscle, 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) converts cortisone (11-dehydrocorticosterone in rodents) to active cortisol (corticosterone in rodents). We aimed to determine the mechanisms underpinning glucocorticoid-induced insulin resistance in skeletal muscle and indentify how 11beta-HSD1 inhibitors improve insulin sensitivity. \ud RESEARCH DESIGN AND METHODS: Rodent and human cell cultures, whole-tissue explants, and animal models were used to determine the impact of glucocorticoids and selective 11beta-HSD1 inhibition upon insulin signaling and action. \ud RESULTS: Dexamethasone decreased insulin-stimulated glucose uptake, decreased IRS1 mRNA and protein expression, and increased inactivating pSer$^{307}$ insulin receptor substrate (IRS)-1. 11beta-HSD1 activity and expression were observed in human and rodent myotubes and muscle explants. Activity was predominantly oxo-reductase, generating active glucocorticoid. A1 (selective 11beta-HSD1 inhibitor) abolished enzyme activity and blocked the increase in pSer$^{307}$ IRS1 and reduction in total IRS1 protein after treatment with 11DHC but not corticosterone. In C57Bl6/J mice, the selective 11beta-HSD1 inhibitor, A2, decreased fasting blood glucose levels and improved insulin sensitivity. In KK mice treated with A2, skeletal muscle pSer$^{307}$ IRS1 decreased and pThr$^{308}$ Akt/PKB increased. In addition, A2 decreased both lipogenic and lipolytic gene expression.\ud CONCLUSIONS: Prereceptor facilitation of glucocorticoid action via 11beta-HSD1 increases pSer$^{307}$ IRS1 and may be crucial in mediating insulin resistance in skeletal muscle. Selective 11beta-HSD1 inhibition decreases pSer$^{307}$ IRS1, increases pThr$^{308}$ Akt/PKB, and decreases lipogenic and lipolytic gene expression that may represent an important mechanism underpinning their insulin-sensitizing action

Ammonia emissions from cattle urine and dung excreted on pasture

Twelve cattle were kept for three days in a circular area of 16 m radius on short pasture and fed with freshly-cut pasture. Ammonia (NH₃) emissions from the urine and dung excreted by the cattle were measured with a micrometeorological mass-balance method, during the cattle presence and for 10 subsequent days. Daily-integrated emission rates peaked on Day 3 of the experiment (last day of cattle presence) and declined steadily for five days thereafter. Urine patches were the dominant sources for these emissions. On Day 9, a secondary emissions peak occurred, with dung pats likely to be the main sources. This interpretation is based on simultaneous observations of the pH evolution in urine patches and dung pats created next to the circular plot. Feed and dung samples were analysed to estimate the amounts of nitrogen (N) ingested and excreted. Total N volatilised as NH₃ was 19.8 (± 0.9)% of N intake and 22.4 (± 1.3)% of N excreted. The bimodal shape of the emissions time series allowed to infer separate estimates for volatilisation from urine and dung, respectively, with the result that urine accounted for 88.6 (± 2.6)% of the total NH₃ emissions. The emissions from urine represented 25.5 (± 2.0)% of the excreted urine-N, while the emissions from dung amounted to 11.6 (± 2.7)% of the deposited dung-N. Emissions from dung may have continued after Day 13 but were not resolved by the measurement technique. A simple resistance model shows that the magnitude of the emissions from dung is controlled by the resistance of the dung crust. © Author(s) 2013

Technical note: A comparison of editing criteria for lying-behaviour data derived from three-dimensional accelerometer devices on grazing dairy cows

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