Application of a novel reference material in an international round robin test on material emissions testing.

Emission testing of products is currently a rapidly increasing field of measurement activity. Labeling procedures for construction products are based on such emission test chamber measurements, and hence, measurement performance should be verified. One possible route is to conduct testing of one material in different laboratories within a round robin test (RRT), ideally using homogeneous reference materials, which can be used within interlaboratory studies or as part of the quality management system to ensure comparable results. The applicability of a lacquer system with nine added VOCs (hexanal, styrene, n-decane, limonene, 2-ethyl-1-hexanol, N-methyl-α-pyrrolidone, 2-ethylhexyl acrylate, dimethyl phthalate, and n-hexadecane) was evaluated in an international RRT with 55 participating laboratories. An intralaboratory quality check confirmed the homogeneity and reproducibility of the lacquer material for most of the compounds (RSD 5%-6%), which was confirmed in the RRT. However, emissions varied for the polar compound N-methyl-α-pyrrolidone and the higher boiling compounds 1,2-dimethyl phthalate, and n-hexadecane which could be traced back to analytical issues. In the RRT, the interlaboratory relative standard deviations (RSDs) ranged from 30% to 65% for all participants but for reference laboratories the range was between 20% and 45%.

Activated sludge rheology: a critical review on data collection and modelling.

Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling and filtration). It therefore is an important property related to process performance, including process economics. To account for this, rheological behaviour is being included in process design, necessitating its measurement. However, measurements and corresponding protocols in literature are quite diverse, leading to varying results and conclusions. In this paper, a vast amount of papers are critically reviewed with respect to this and important flaws are highlighted with respect to rheometer choice, rheometer settings and measurement protocol. The obtained rheograms from experimental efforts have frequently been used to build viscosity models. However, this is not that straightforward and a lot of errors can be detected with respect to good modelling practice, including fair model selection criteria, qualitative parameter estimations and proper model validation. These important steps are however recurrently violated, severely affecting the model reliability and predictive power. This is illustrated with several examples. In conclusion, dedicated research is required to improve the rheological measurements and the models derived from them. At this moment, there is no guidance with respect to proper rheological measurements. Moreover, the rheological models are not very trustworthy and remain very "black box". More insight in the physical background needs to be gained. A model-based approach with dedicated experimental data collection is the key to address this.

Electro-optical tunable waveguide Bragg gratings in lithium niobate induced by femtosecond laser writing.

We report the fabrication of femtosecond laser-induced, first-order waveguide Bragg gratings in lithium niobate in the low repetition rate regime. Type-II waveguides are written into an x-cut lithium niobate wafer and structured periodically to achieve narrowband reflections at wavelengths around 1550 nm. Additionally, electrodes are employed to allow for electro-optic tuning of the spectral response. We demonstrate wavelength control of the central reflection peak by applying a static external electric field. A maximum shift of the reflection peak of Δλ = 625 pm is observed.

[Intravitreal injections during anticoagulant treatment]. / Intravitreale Injektionen bei Antikoagulation.

BACKGROUND: The number of intravitreal injections has increased steadily over the past few years. The aim of this prospective study was to evaluate the safety of intravitreal injections in patients under concurrent oral anticoagulation or antiplatelet therapy. PATIENTS AND METHODS: 57 patients who underwent consecutively 80 intravitreal injections of Ranibizumab, Bevacizumab or triamcinolone were included in the study. The majority of the patients was treated with Ranibizumab and received antiplatelet therapy. Post-injection intra- or extraocular haemorrhages were documented. RESULTS: Small subconjunctival haemorrhages were noted in 45 % of the eyes. No patient experienced a subtotal subconjunctival or vitreous haemorrhage. There was no difference between patients who received oral anticoagulation and those with antiplatelet therapy. CONCLUSION: This study suggests that intravitreal injections can be performed without cessation of oral anticoagulation or antiplatelet therapy.

[Considering and tackling tobacco smoking in the context of adolescent development]. / Tabak-Konsum im Kontext adoleszenter Entwicklung - was wir dagegen tun können und sollen.

The prevalence of smoking among young people is still on a high level. Many adolescents are incessantly attracted by advertising and other messages promising a fashionable, young and independent lifestyle with cigarettes as imperative symbols. Those adolescents suffering from cognitive, mental or social problems or being genetically more vulnerable have the greatest risk to misuse nicotine and to become addicted for many years. Unfortunately, being diagnosed with asthma or diabetes does not deter adolescents from smoking, thus increasing the burden of their chronic disease. Of similar concern is the considerable number of smoking young people at the reproductive age. In the last few years, only modest progress has been observed in the development of programmes, which are suited to diminish the rate of young smokers. There is a lack of effective strategies that could help them to get motivated and to stop smoking. Primary care physicians are in an unique position to contribute to adolescent smoking cessation. This article provides information to physicians on how to best accomplish this task. In order to reach sustainable changes in adolescent smoking behaviour, rigorous political steps are necessary which target on diminishing the social acceptance and attractiveness of smoking in general and on the reduction of the number of adult smokers, rather than exclusively focussing on adolescent smoking. This policy has to be supplemented with comprehensive steps to improve education and future life perspectives of adolescents.

[Development, implementation and evaluation of a program for the cessation of smoking for adolescents and young adult smokers]. / Entwicklung, Implementation und Evaluation eines Programms zur Entwöhnung vom Rauchen für jugendliche und junge erwachsene Raucher.

AIM: Assessment of the smoking cessation programme "Just be smoke free". METHOD: Follow-up data assessment of the participants who registered for the programme between April 2002 and March 2003. INTERVENTION: "Just be smoke free" is a smoking cessation programme targeting adolescents and young adults. Target groups are not only smokers, but also non- and ex-smokers. Moreover the project takes into account the different stages smokers undergo with regard to their motivation to stop smoking. Smokers who are not prepared to quit smoking are offered an individualised "smoker's profile" in order to sensitise them to their smoking behaviour, motives and risk situations. Smokers who are prepared to give up, are provided with a self-help cessation manual. As an incentive, on four occasions per year, participants can win cash prizes of up to 1,000 Euro. RESULTS: From April 2002 to March 2003, 1,417 smokers registered for the programme, of which 1,265 wanted to quit and 152 were interested in a "smoker's profile". The mean age of the participants was 21.5 years and 56.7 % were female. In addition, 2,132 used the internet page for the programme. 408 smokers took part in the follow-up measurement (retention rate 32.3 %). Of these, 46.1 % (N = 188) reported to have ceased to smoke. In a projected analysis considering those who did not take part in the follow-up measurement as smokers - the quit rate was 14.9 %. CONCLUSIONS: A large number of smoking adolescents and young adults were covered by the programme. The quit rate can be considered as good, also in comparison to international smoking cessation studies.

Using cartilage to repair bone: an alternative approach in tissue engineering.

Materials and techniques currently used for bone replacement/repair conform to the current paradigm, relying on bone or bone products to produce bone or induce bone formation. Yet, nature forms and heals most of the skeleton by ossification of a cartilaginous model. In this study, we cultured aggregates of E10.5 or E12 mouse embryonic limb cells in the bioreactor for 3 weeks, determined the stages of cartilage differentiation attained, and assessed the ossification and bone healing potential of the spheroids by implantation adjacent to, or directly in, a skull defect. Cultured spheroids had large cartilaginous areas, sometimes with cellular arrangements characteristic of growth plate zones. Aggregates implanted for 2 weeks adjacent to a defect mineralized and ossified (histology, micro-CT). Defects with implants had a central mass of differentiated and differentiating bone, with osteoclast activity, filling the defect. Controls had considerable remodeling on the bone edges demarcating the still present defect. This study shows that cartilage, grown in the bioreactor for 3 weeks, ossified when implanted adjacent to a bone defect, and when implanted directly in a defect, contributed to its healing. Our ability to grow differentiated bone-forming cartilage for implantation is an alternative approach in the field of bone repair.

[Structured concept for the establishment of a broad and ambulatory care of patients with type 2 diabetes: one-year evaluation of a regional teaching organization]. / Strukturkonzept zur Etablierung einer flächendeckenden ambulanten Versorgung von Patienten mit Typ-2-Diabetes. Ein-Jahres-Evaluation eines regionalen Schulungsvereins.

BACKGROUND: The increasing prevalence of diabetes mellitus and its long-term complications are associated with an expanding social medical problem. In order to originate an established teaching and training program on a physician-based level in short time, three specialist diabetes centers from Lübeck transferred their concept to a diabetes organization based on 17 physicians who had only rarely undertaken any diabetes teaching before. We investigated the achievement and effectiveness of this concept in a prospective multicenter evaluation one year after the patients had received structured diabetes teaching by the organization. PATIENTS AND METHODS: Physicians and their teaching staff were trained by the specialists from the diabetes centers according to an official agreement. Patients were treated by each practice, while the diabetes teaching was done centrally by the organization through a diabetes assistant/dietician based on a modified official diabetes teaching and training program (ZI-program). 230 of 250 patients (120 male, 110 female) were reinvestigated one year after they had received the teaching. The group consisted of 179 non-insulin-treated (NIB; 94 via physicians, 85 via specialists) and 51 insulin-treated (IB; 19 via physicians, 32 via specialists) participants. RESULTS: The average age of NIB was 60.4+/-9.8 years, while IBs were 68.8+/-7.3 years old. HbA (1c) values were reduced in both groups, NIB and IB, by approximately 1% (NIB: 7.59+/-1.97% to 6.59+/-1.84%; IB: 8.47+/-1.35% to 7,36+/-1,38 %; p < 0,001). In the NIB-group the BMI was reduced by 0,64+/-0,14 kg x m (-2), whereas it was increased in the IB-group by 0.33+/-0.24 kg x m(-2) (NIB: 30.55+/-0.40 to 29.91+/-0.39 kg x m(-2), p < 0.001; IB: 28.83+/-0.74 to 29.16+/-0.75 kg x m(-2), p = 0.82). CONCLUSION: The transfer of established teaching and training concepts of specialist diabetes centers to a newly founded, physician-based diabetes organization resulted in a broad, effective and long-lasting medical care of patients with type 2 diabetics treated without or with insulin. The results are superior to those of other evaluations based on diabetes training ZI-programs.

Conjugated linoleic acid supplementation in humans: effects on fatty acid and glycerol kinetics.

Recent studies with mouse adipocytes have shown that dietary conjugated linoleic acid (CLA) may reduce body fat by increasing lipolysis. The present study examined the effect of CLA supplementation on fatty acid and glycerol kinetics in six healthy, adult women who were participating in a controlled metabolic ward study. These women were fed six CLA capsules per day (3.9 g/d) for 64 d following a baseline period of 30 d. The subjects were confined to a metabolic suite for the entire 94-d study, where diet and activity were controlled and held constant. The rate of appearance (Ra) of glycerol, which indicates lipolytic rates, was similar at baseline and after 4 wk of CLA supplementation at rest (1.87 +/- 0.21 and 2.00 +/- 0.39 micromol/kg/min, respectively) and during exercise (7.12 +/- 0.74 and 6.40 +/- 0.99 micromol/kg/min, respectively). Likewise, the Ra of free fatty acids (FFA) was not significantly different after 4 wk of dietary CLA at rest (2.72 +/- 0.06 and 2.74 +/- 0.12 micromol/kg/min, respectively) or during exercise (6.99 +/- 0.40 and 5.88 +/- 0.29 micromol/kg/min, respectively). CLA supplementation also had no effect on the percentage of FFA released from lipolysis that were re-esterified. The apparent rate of FFA re-esterification was 65.2 +/- 4.2% at rest and 32.1 +/- 3.44% during exercise. Four weeks of CLA supplementation had no significant effect on fatty acid or glycerol metabolism in healthy, weight-stable, adult women.

AI in medicine on its way from knowledge-intensive to data-intensive systems.

The last 20 years of research and development in the field of artificial intelligence in medicine (AIM) show a path from knowledge-intensive systems, which try to capture the essential knowledge of experts in a knowledge-based system, to data-intensive systems available today. Nowadays enormous amounts of information is accessible electronically. Large datasets are collected continuously monitoring physiological parameters of patients. Knowledge-based systems are needed to make use of all these data available and to help us to cope with the information explosion. In addition, temporal data analysis and intelligent information visualization can help us to get a summarized view of the change over time of clinical parameters. Integrating AIM modules into the daily-routine software environment of our care providers gives us a great chance for maintaining and improving quality of care.

Accidents and injuries among U.S. Navy crewmembers during extended submarine patrols, 1997 to 1999.

Accidents and injuries, the most common cause of morbidity in military populations, result in a significant number of work days lost each year and account for 75% of all active duty deaths. Rates of accidents and injuries during U.S. Navy submarine deployments have not been evaluated previously. A database designed to monitor the health of submarine crew-members was used to examine the rates and causes of accidents among deployed crewmembers aboard 196 submarine patrols between 1997 and mid 1999. The most common category of injuries was open wounds, followed by sprains and strains, contusions, superficial injuries, burns, and others. Rates of accidents and injuries decreased with increasing age and duration of military service. Among submariners working in supply departments, the rates were more than two times those of crewmembers working in other departments. Based on these data, among a submarine crew of 100 men at sea for 100 days, approximately four to five accidents or injuries might be expected and would result in an average of about 2 days of light or no duty per injury. Rates of accidents and injuries were very low; however, focused safety training could reduce rates among younger and less experienced crewmembers as well as among those working in particular areas of the submarine.

Support for fast comprehension of ICU data: visualization using metaphor graphics.

OBJECTIVES: The time-oriented analysis of electronic patient records on (neonatal) intensive care units is a tedious and time-consuming task. Graphic data visualization should make it easier for physicians to assess the overall situation of a patient and to recognize essential changes over time. METHODS: Metaphor graphics are used to sketch the most relevant parameters for characterizing a patient's situation. By repetition of the graphic object in 24 frames the situation of the ICU patient is presented in one display, usually summarizing the last 24 h. RESULTS: VIE-VISU is a data visualization system which uses multiples to present the change in the patient's status over time in graphic form. Each multiple is a highly structured metaphor graphic object. Each object visualizes important ICU parameters from circulation, ventilation, and fluid balance. CONCLUSION: The design using multiples promotes a focus on stability and change. A stable patient is recognizable at first sight, continuous improvement or worsening condition are easy to analyze, drastic changes in the patient's situation get the viewers attention immediately.

In vitro effects of fenretinide on cell-matrix interactions.

BACKGROUND: Understanding the molecular basis of the metastatic spread of cancer and the underlying mechanisms is crucial for the development and appropriate clinical use of novel therapeutic agents directed at prevention of metastasis. Retinoids have been reported to inhibit cell proliferation, modulate cell differentiation, enhance apoptosis and to prevent the conversion of in situ cancer to locally invasive malignancy by suppressing the invasive process as well as by inhibiting angiogenesis. Fenretinide (4-HPR), a synthetic derivative of retinoic acid, is less toxic than natural retinoids and is active in the prevention and treatment of a variety of tumours in animal models. Its efficacy in cancer chemoprevention and therapy has been investigated in clinical trials. MATERIALS AND METHODS: In order to evaluate the effects of 4-HPR on the late stages of tumour progression, chemically transformed BALB/c 3T3 cells, showing a fully malignant phenotype, were exposed to 4-HPR (0.25-10 microM; 72 hours pre-treatment) and then analysed for in vitro invasive ability. The possible mechanisms of action responsible for the anti-invasive activity of 4-HPR were investigated, analysing cellular adhesion, motility, and proteolytic capability. RESULTS: Data showed that 4-HPR significantly inhibited the invasive phenotype of chemically transformed cells; the reduction in Matrigel invasion was dose-dependent and seemed not to be related to cytotoxic effects or reduction in cell proliferation rates induced by 4-HPR assayed doses. The 4-HPR-induced decrease in chemotactic motility of transformed cells correlated well with the invasion inhibition. 4-HPR, at active concentrations, differently affected cell adhesion to the extracellular matrix, depending on the coating substrate used (laminin, collagen IV, fibronectin and vitronectin). 4-HPR treatment significantly enhanced cell adhesion to laminin, while reducing cell-vitronectin attachment. It did not modify the attachment of the cells to fibronectin and collagen IV. Zymographic analysis failed to demonstrate 4-HPR involvement in the modulation of the activity and expression of gelatine degrading enzymes. CONCLUSION: These data suggest that 4-HPR inhibits tumour cell invasion through a basement-like matrix, by suppressing chemotactic motility and by altering cell-matrix interactions.

Graftskin heals an ulcer on an amputation stump.

BACKGROUND: A 51-year-old man presented with a chronic ulcer of 28 years' duration on the amputation stump of his right foot. The prosthesis was aggravating the ulcer, despite multiple therapies. OBJECTIVE: To heal the ulcer and avoid a below-the-knee amputation. Graftskin, a bilayered living skin construct, was applied. METHODS: Graftskin was sutured in place following gentle debridement. Pentoxifylline was given to improve circulation. The dressing was changed 5 days after Graftskin application, then weekly for 7 weeks. RESULTS: Crusting was evident at 3 weeks, with an underlying white coating at 4 weeks. By 7 weeks, full reepithelialization was present under the crust and no ulceration remained. Over succeeding weeks the ulcer bed became flush with the surrounding skin. The patient's pain ceased, and some sensation and warmth returned to the stump. CONCLUSION: Graftskin treatment successfully healed a chronic ulcer, possibly preventing a more extensive amputation.

Conjugated linoleic acid supplementation in humans: effects on circulating leptin concentrations and appetite.

Conjugated linoleic acid (CLA) has been demonstrated to reduce body fat in animals. However, the mechanism by which this reduction occurs is unknown. Leptin may mediate the effect of CLA to decrease body fat. We assessed the effects of 64 d of CLA supplementation (3 g/d) on circulating leptin, insulin, glucose, and lactate concentrations in healthy women. Appetite was assessed as a physiological correlate of changes in circulating leptin levels. Analysis of plasma leptin concentrations adjusted for adiposity by using fat mass as a covariate showed that CLA supplementation significantly decreased circulating leptin concentrations in the absence of any changes of fat mass. Mean leptin levels decreased over the first 7 wk and then returned to baseline levels over the last 2 wk of the study in the CLA-treated group. Appetite parameters measured at around the time when the greatest decreases in leptin levels were observed showed no significant differences between supplementation and baseline determinations in the CLA-supplemented group or between the CLA and placebo-supplemented groups. There was a nonsignificant trend for mean insulin levels to increase toward the end of the supplementation period in CLA-treated subjects. CLA did not affect plasma glucose and lactate over the treatment period. Thus, 64 d of CLA supplementation in women produced a transient decrease in leptin levels but did not alter appetite. CLA did not affect these parameters in a manner that promoted decreases of adiposity.

A method for monitoring the health of US Navy submarine crewmembers during periods of isolation.

BACKGROUND: With the expansion of the manned space program, an essential consideration in planning is the medical support necessary for long-term missions. Information on analogous populations serving in isolated and/or contained environments may be useful in predicting health risks for astronauts. METHODS: The present study evaluates rates of health events that occur in a highly screened, healthy military population during periods of isolation. A centralized database was designed to collect medical encounter data from U.S. Navy submarines and contains demographic information, crew rosters for each patrol, medical encounter notes, accident reports, medical evacuation reports, vital signs and laboratory data. The population included in the present analysis is composed of crewmembers aboard 136 submarine patrols between January 1, 1997 and December 31, 1998. RESULTS: A total of 2,044 initial visits to medical staff and 973 re-visits for the same condition were recorded during these patrols. Potentially mission-impacting medical events reported among crewmembers were rare (i.e., among a crew of 10 individuals, only 1-2 medical events would be expected to occur during a 100 d-mission). The most common category of medical events was injury, followed by respiratory illnesses (URIs), skin problems (minor infections, ingrown toenail), symptoms and ill-defined conditions, digestive disorders, infectious conditions, sensory organ problems (ear and eye), and musculoskeletal conditions.

Factors associated with patients' participation in rehabilitation services: a comparative injury analysis 12 months post-discharge.

PURPOSE: To determine key characteristics or factors associated with rehabilitation participation during the first year following discharge for persons with either traumatic brain injury (TBI), spinal cord injury (SCI), intra-articular fracture (IAF), or burn injury (BURNS). METHOD: Medical records and longitudinal survey [telephone questionnaire] data were collected for persons in the four injury groups and analyzed using hierarchical logistic regression procedures for each domain of factors. RESULTS: The only significant predictors with odds ratios greater than one were those for vocational rehabilitation participation. TBI patients lacking private insurance were 2.6 times more likely to participate in vocational rehabilitation; older SCI and TBI patients are about twice as likely to participate in vocational rehabilitation; and finally those with IAF or BURNS who are married at 12 months post discharge are 11.5 and 4.4 times respectively more likely to participate in vocational rehabilitation. CONCLUSION: Those lacking valuable socio-economic resources, such as private insurance (for TBI) and social support systems provided by marriage (for BURNS and IAF patients) are much more likely to be referred to vocational rehabilitation. This is true for older SCI and TBI patients as well. Lacking such resources, patients may be viewed by referral agents as less likely to benefit from in or outpatient rehabilitation.

Effects of the protease inhibitor antipain on cell malignant transformation.

BACKGROUND: Several natural products have been found to exhibit a chemopreventive activity both in in vivo and in vitro experimental systems. Among them, protease inhibitors seem to play a key role in the regulation of growth and phenotypic expression of transformed cells as well as in the regulation of the late events of carcinogenesis. We evaluated the effect of antipain (AP), a natural protease inhibitor, on chemically induced BALB/c 3T3 cell transformation, on invasion and chemotactic motility of transformed cells and on their gelatinase expression. METHODS: BALB/c 3T3 cells were plated and exposed to 2.5 micrograms/ml 3-MCA or 50 micrograms/ml, 1,2-DBE. The effect of a non-cytotoxic dosage of AP (10 microM) was studied by: a) pretreating cells with AP for 48 hours before the carcinogen exposure; b) adding AP simultaneously to the carcinogen treatment; c) chronic addition of AP at each medium change throughout the experimental duration. The effectiveness of the treatment was analysed as the ability to reduce or inhibit the occurrence of transformed foci. Modulation of the invasive phenotype by anti-transforming dosages of AP was evaluated by in vitro Matrigel invasion assay. Gelatin zymography was performed in order to assess AP regulation of proteolytic enzymes, such as metalloproteases, involved in invasion and metastasis. RESULTS: AP treatment can reduce the transformation rate both in 3-MCA- and 1,2-DBE-initiated cells. Its effectiveness depends on the administration schedule, and chronic addition seems to be the most effective treatment. The concentration of AP, which is effective in the antitransformation assay, is not able to significantly affect the migration and invasion of chemically transformed cells or their gelatinase activity. CONCLUSIONS: AP can suppress chemically induced BALB/c 3T3 cell transformation through mechanisms which do not involve modulation of the invasive phenotype.

Determinants of self-efficacy among persons with spinal cord injuries.

The purpose of this study was to determine the factors affecting self-efficacy among persons with spinal cord injury (SCI). The study population consisted of 105 persons with SCI who were discharged from one of eight hospitals in north central Alabama between October 1989 and September 1992. Data were derived from a retrospective acute-care medical record review and 12-month annual follow-up telephone interviews. The findings indicate that high self-efficacy is significantly associated with less severe neurological impairment, being white, employed at injury, having a high-school education or beyond, and having an unintentional injury. In terms of marital status our data indicate the odds of divorced persons having high self-efficacy are 8.2 (CL = 0.919, 74.1) times those of married persons. In addition, 64% of those who were divorced during the 12 months after injury had high self-efficacy compared to 50% of those who were divorced prior to injury.

Effective data validation of high-frequency data: time-point-, time-interval-, and trend-based methods.

Real-time systems for monitoring and therapy planning, which receive their data from on-line monitoring equipment and computer-based patient records, require reliable data. Data validation has to utilize and combine a set of fast methods to detect, eliminate, and repair faulty data, which may lead to life-threatening conclusions. The strength of data validation results from the combination of numerical and knowledge-based methods applied to both continuously-assessed high-frequency data and discontinuously-assessed data. Dealing with high-frequency data, examining single measurements is not sufficient. It is essential to take into account the behavior of parameters over time. We present time-point-, time-interval-, and trend-based methods for validation and repair. These are complemented by time-independent methods for determining an overall reliability of measurements. The data validation benefits from the temporal data-abstraction process, which provides automatically derived qualitative values and patterns. The temporal abstraction is oriented on a context-sensitive and expectation-guided principle. Additional knowledge derived from domain experts forms an essential part for all of these methods. The methods are applied in the field of artificial ventilation of newborn infants. Examples from the real-time monitoring and therapy-planning system VIE-VENT illustrate the usefulness and effectiveness of the methods.