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Single steps in cleaning a fouled heat exchanger surface eventually determine the cleaning kinetic and thus the overall performance of a cleaning process. Up to date the complex mechanisms of the mutual supportive processes in cleaning are not yet fully understood. This contribution presents a stepwise approach to investigate the individual process steps starting with the diffusion of the cleaning agent NaOH into a WPI gel, studied at stationary and flow conditions. In the experiments, temperature affected both the diffusion step and the subsequent removal but to different extents. This was further specified and it was found that there is an induction time for the release of disengaged proteins, accounting for the speed of the temperature dependent degrading reactions. [ABSTRACT FROM AUTHOR]

CIP processes in milk processing plants are frequently oversized to reliably meet hygienic and safety requirements. Cleaning follows a fixed protocol, but the exact mechanisms and intermediate products are often unknown. This study presents an experimental approach to elucidate the interaction between alkaline and acidic treatment with special regard to the impact of acid on proteinaceous deposits. The protein containing fouling layers become yellowish in colour by acidic treatment; this is attributed to the xantho-proteic reaction and no efficient removal is thereby achieved. In contrast, the removal is efficient if an efficient initial alkaline treatment step is performed. An efficient initial alkaline treatment step was identified as crucial for the further course of cleaning and a short alkaline treatment soaked the entire soil, which enabled an efficient subsequent acidic removal. Lower concentrations of HNO 3 demonstrate more efficient cleaning than higher ones, suggesting an optimum acid concentration during CIP. [ABSTRACT FROM AUTHOR]

The concentration dependence (range 1–40 %) of the dynamics of monodisperse polymer latex dispersions (particle diameters 41–326 nm) is studied by fiber-optic quasielastic light scattering (FOQELS). The experiments reveal that despite the high turbidity of the samples multiple light scattering has negligible influence on the data when single-mode fibers are employed. This is explained by the diameter of the single-mode fiber core being much smaller than the scattering mean free paths in the dispersions. It is further shown that the autocorrelation functions can be interpreted in terms of the dynamic structure factor of the dispersions. When the particle diameter is raised from 41 to 326 nm the data show that FOQELS probes mutual diffusion for the smaller particles and self-diffusion for the larger ones. [ABSTRACT FROM AUTHOR]

Abstract: Background: CPAP remains the treatment of choice for Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS), but compliance with CPAP is poor. Of many interventions tried to improve CPAP compliance, only education and humidification have been shown to be of benefit. Our purpose was to develop and pilot test a video to enhance patient understanding of obstructive sleep apnea and of the purpose, logistics, and benefits of CPAP use in patients newly diagnosed with OSAHS. A patient''s CPAP compliance in the first few weeks after starting its use is predictive of long-term compliance with CPAP treatment. It is imperative that patients grasp at the outset both the severity of OSAHS and the effectiveness of CPAP therapy. Methods: An educational video script was written based on recommendations for patient educational video materials and covering identified misconceptions about OSAHS and perceived barriers to CPAP use. The videotape is 15min in length and features two middle-aged males, one African-American and one Euro-American, discussing OSAHS and CPAP in a factory break room. Results: In a randomized two-group design with a control group, patients with newly diagnosed OSAHS, and who viewed the CPAP educational video on their first clinic, were significantly more likely to use their machine and to return for a 1-month clinic visit than were those in the control group. Conclusion:Viewing of a patient education video at the initial visit was found to significantly improve the rate of return for the follow-up visit. [Copyright &y& Elsevier]

This article examines the relationship between substance use and violence across rural-urban and Appalachian places of residence. The data come from a larger study on the health service use of 637 men who have a history of chronic substance abuse and who were incarcerated in four Kentucky prisons. The findings generally support previous research on substance use and violence but do not support Fischer's (1995) subculture theory of urbanism. Contrary to expectations, the population size of the prisoners' residence was not significantly associated with the prisoners' levels of violent victimization, violence toward others, violence toward intimate partners, or overall violence in the year prior to incarceration. Appalachian residency was also not associated with violence. Recognizing that the effect of substance use on violence perpetrated against others does not vary significantly by urban or rural residence may be helpful for designing violence prevention programs and planning law enforcement efforts. [ABSTRACT FROM AUTHOR]

It has been recognised that the success of any clinical encounter rests largely on the effectiveness of the patient-provider interaction. While it is clear that practitioners must deal sensitively with patients of other cultural backgrounds, what is lacking is skills-based training on precisely how these concepts should be applied within real life situations. A module on interpreter use with limited English proficiency patients was introduced for the first time into the communication and interviewing course undertaken by second year medical students at the UK College of Medicine, Kentucky. The goals of the module were to alert students to the necessity of skills training in interpreter use and to teach them several specific skills.

Abstract: Recent Eddy current investigations on the cladding of nuclear fuel pins have shown that the apparent oxide layers are falsified due to unexpected magnetic properties of corrosion product deposits. Analyses by Scanning Electron Microscopy (SEM) or Electron Probe Micro Analysis (EPMA) demonstrated that the deposit layer consists of complex 3-d element oxides (Ni, Mn, Fe) along with Zn, since the reactor operates with a Zn addition procedure to reduce buildup of radiation fields on the recirculation system surfaces. The oxides crystallise in ferritic spinel structures. These spinels are well-known for their magnetic behaviour. Since non-magnetic zinc ferrite (ZnFe2O4) may become magnetic when doped with even small amounts of Ni and/or Mn, their occurrence in the deposit layer has been analyzed. The magnetic permeability of zinc ferrite, trevorite and jacobsite and their solid solutions are estimated by magnetic moment additivity. From the void history examination, the low elevation sample (810mm) did not face significant boiling during the irradiation cycles suggesting growth of crystals with theoretical value of the magnetic permeability for the averaged heterogeneous CRUD layer of 9.5±3. Meanwhile, crystallizes at the mid elevation (1810mm) with theoretical magnetic permeability for the CRUD layer of 4.2±1.5 at the investigated azimuthal location. These theoretical data are compared with the magnetic permeability of the corrosion product deposited layers gained from reactor pool side Eddy current (EC) analyses (9.0±1.0 for low and 3.5±1.0 for high elevation). The calculated thicknesses and magnetic permeability values of the deposition layers (estimated by MAGNACROX multifrequency EC method) match together with these estimated using an “ion magnetic moment additivity” model. [Copyright &y& Elsevier]

Nebel K, Stude P, Lüdecke C, Wiese H, Diener H-C&Keidel M. Prospective PC-interactive pressure algesimetry of post-traumatic neck pain after whiplash injury. Cephalalgia 2004. London. ISSN 0333-1024Cervical pain is a prominent symptom in both acute whiplash injury and late whiplash syndrome. However, no systematic analysis of post-traumatic pain development covering several weeks has yet been performed in whiplash patients. It was the aim of the present study to analyse the duration and course of post-traumatic muscle pain due to whiplash injury in a prospective follow-up examination with short investigation intervals. A recovery of initially increased muscle pain after whiplash injury within 1 month was hypothesized. Pressure pain of the splenius and trapezius muscles was recorded using PC-interactive pressure algesimetry. Whiplash patients were investigated during the acute injury stage and after 3, 4, and 6 weeks and compared with matched controls. We found significantly increased pressure pain of the splenius and trapezius muscles in the acute stage of whiplash injury. After 4 weeks patients’ scores of pain parameters were comparable to those of healthy control subjects. Within the patient group the first changes of pressure pain were observed within 3 (splenius) and 4 weeks (trapezius). For most patients the recovery dynamics lasted 4–6 weeks. A minority of patients did not show any improvement after 6 weeks. The present study shows that the dynamics of pressure pain due to whiplash injury can be quantified by means of PC-interactive pressure algesimetry. Our results confirm the clinical experience that the acute post-traumatic cervical syndrome normally subsides within weeks. [ABSTRACT FROM AUTHOR]

Stude P, Nebel K, Lüdecke C, Wiese H, Diener H-C&Keidel M. Quantification of acute neck pain following whiplash injury by computer-aided pressure algesimetry. Cephalalgia 2004. London. ISSN 0333-1024Until now the clinical investigation of cervical pain due to whiplash injury is mainly based on finger palpation. The present study introduces a PC-interactive pressure algesimetry to standardize cervical pain measurement. Pressure pain scores of the splenius and trapezius muscles of 23 patients with an acute cervical syndrome after whiplash injury were compared to those of 24 healthy subjects. The pressure painfulness of neck and shoulder muscles was significantly increased in whiplash patients. The splenii muscles showed an equally increased muscle pain whereas the trapezii muscles showed a left-sided preponderance of painfulness, possibly due to the seat belt position in this group of motor vehicle drivers. The computer-interactive pressure algesimetry enables a standardized and rater-independent quantification of the cervical syndrome with neck and shoulder pain caused by whiplash injury. [ABSTRACT FROM AUTHOR]

River bank or slow sand filtration is a major procedure for processing surface water to drinking water in central europe. In order to model the performance of river bank and slow sand filtration plants, we are studying the different mechanisms by which the elimination of pathogens is realized. An important question concerning the mode of action of slow sand filters and river bank filtration units is the role of the colmation layer or "schmutzdecke" on the elimination of human pathogens. The schmutzdecke is an organic layer which develops at the surface of the sand filter short after the onset of operation. We have inoculated a pilot plant for slow sand filtration with coliphages and determined their rate of breakthrough and their final elimination. In the first experiment, with a colmation layer still missing, the breakthrough of the coliphages in the 80 cm mighty sandy bed amounted to ca. 40 %. In contrast, less than 1 % of coliphages escaped from the filter as the same experiment was repeated two months later, when a substantial colmation layer had developed. Our preliminary conclusions are that the colmation layer is extremely efficient in eliminating of viruses. [ABSTRACT FROM AUTHOR]

The used fuel discharged from nuclear power plants constitutes the main contribution to nuclear waste in countries which do not undertake reprocessing. As such, its disposal requires isolation from the biosphere in stable deep geological formations for long periods of time (some hundred thousand years) until its radioactivity decreases through the process of radioactive decay. Ways for significantly reducing the volumes and radiotoxicities of the waste and to shorten the very long times for which the waste must be stored safely are being investigated. This is the motivation behind the partitioning and transmutation (P&T) activities worldwide. This paper addresses the potential impact of P&T on the long-term disposal of nuclear waste. In particular, it evaluates how realistic P&T scenarios can lead to a reduction in the time required for the waste to be stored safely. The calculations have been done independently by three research groups: ITU and FZK in Germany, and by the CEA in France. [ABSTRACT FROM AUTHOR]