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Levodopa is routinely co-administered with carbidopa in the management of Parkinson’s disease. Although the aforementioned combination therapy is effective, there may be fluctuating plasma levels of levodopa after oral administration. We formulated and evaluated the kinetic characteristics of the chitosan-pectin-based multiparticulate matrix of levodopa and carbidopa. Pectin was extracted from the cocoa husk, and the chitosan-pectin-based matrix was prepared by wet granulation. Formulations were evaluated for drug-excipient compatibility, drug content, precompression properties and in vitro release. For pharmacokinetic evaluation, rats were put into groups and administered either chitosan-pectin based matrix of levodopa/carbidopa, Sinemet® CR or levodopa/carbidopa immediate release powder. Rats were administered the different formulations of levodopa/carbidopa (20/5 mg/kg) per os every 12 hours. The pharmacokinetic parameters of levodopa were estimated for the various treatment groups. The percentage content of levodopa and carbidopa in the various formulations was within the acceptance criteria. The AUC0-24 for levodopa/carbidopa multiparticulate matrix (Formulation 3: 484.98 ± 18.70 µg.hr/mL); Formulation 4: 535.60 ± 33.04 µg.hr/mL), and Cmax (Formulation 3: 36.28 ± 1.52 μg/mL; Formulation 4: 34.80 ± 2.19 μg/mL) were higher than Sinemet® CR (AUC0-24 262.84 ± 16.73 µg.hr/mL and Cmax 30.62 ± 3.37 μg/mL). The t1/2 of the new formulation was longer compared to Sinemet® CR.

Medium Density Insulating Boards, based on vermiculite, are used for the insulating lining of ladles in steel production. In service, carbon monoxide is generated from oxidation of neighbouring Magnesia – Carbon bricks and diffuses through the refractory brick lining to deposit carbon in the colder insulating lining via the Boudouard reaction. Characterization by laser flash and hot disk measurements of original and post-mortem samples reveals an approximate increase by 26% in the overall thermal conductivity of the board to 0.34 W m−1 K−1 at room temperature following 15 months service. This is attributed to carbon and chloride phases detected by X-ray fluorescence and energy dispersive X-ray spectroscopy in the outermost zone of the board, cut into three zones for analysis along the heat flow direction. The increase in thermal conductivity is reduced to 17% when the thermal gradient in service conditions is considered.

The immune system offers several mechanisms of response to harmful microbes that invade the human body. As a first line of defense, neutrophils can remove pathogens by phagocytosis, inactivate them by the release of reactive oxygen species (ROS) or immobilize them by neutrophil extracellular traps (NETs). Although recent studies have shown that bacteriophages (phages) make up a large portion of human microbiomes and are currently being explored as antibacterial therapeutics, neutrophilic responses to phages are still elusive. Here, we show that exposure of isolated human resting neutrophils to a high concentration of the Pseudomonas phage PAK_P1 led to a 2-fold increase in interleukin-8 (IL-8) secretion. Importantly, phage exposure did not induce neutrophil apoptosis or necrosis and did not further affect activation marker expression, oxidative burst, and NETs formation. Similarly, inflammatory stimuli-activated neutrophil effector responses were unaffected by phage exposure. Our work suggests that phages are unlikely to inadvertently cause excessive neutrophil responses that could damage tissues and worsen disease. Because IL-8 functions as a chemoattractant, directing immune cells to sites of infection and inflammation, phage-stimulated IL-8 production may modulate some host immune responses.

Abstract Background Sarcoidosis most commonly affects lungs and intrathoracic lymph nodes, but any other organ can be involved. In epidemiological studies, many occupational and environmental exposures have been linked to sarcoidosis but their relationship with the disease phenotype has barely been studied. Objective To investigate how occupational and environmental exposures prior to diagnosis relate to organ involvement in patients with sarcoidosis Methods We retrospectively studied patients seen at a sarcoidosis clinic between 2017 and 2020. Patients were included if they had a clinical presentation consistent with sarcoidosis and histologically confirmed epithelioid granulomas or had Löfgren syndrome. In a case–case analysis using multivariable logistic regression we calculated odds ratios (OR) of prespecified exposure categories (based on expert ascertainment) for cases with a given organ involvement versus cases without this organ involvement. Results We included 238 sarcoidosis patients. Sarcoidosis limited to pulmonary involvement was associated with exposure to inorganic dust prior to diagnosis (OR 2.11; 95% confidence interval [CI] 1.11–4.17). Patients with liver involvement had higher odds of contact with livestock (OR 3.68; 95% CI 0.91–12.7) or having jobs with close human contact (OR 4.33; 95% CI 1.57–11.3) than patients without liver involvement. Similar associations were found for splenic involvement (livestock: OR 4.94, 95% CI 1.46–16.1; close human contact: OR 3.78; 95% CI 1.47–9.46). Cardiac sarcoidosis was associated with exposure to reactive chemicals (OR 5.08; 95% CI 1.28–19.2) or livestock (OR 9.86; 95% CI 1.95–49.0). Active smokers had more ocular sarcoidosis (OR 3.26; 95% CI 1.33–7.79). Conclusions Our study indicates that, in sarcoidosis patients, different exposures might be related to different organ involvements—hereby providing support for the hypothesis that sarcoidosis has more than one cause, each of which may promote a different disease phenotype.

The article highlights challenges that face the tourism industry due to the COVID-19 pandemic. The analytical reports identified key negative trends and the impact of the tourism industry on socio-economic development indicators. The analysis of the historical facts of the development of crisis phenomena in the tourism sector provided an opportunity to state the fact of cyclical formation on the basis of biological threats in different regions of the world. In the context of this study, the main problems ofthe development of the tourism industry of Ukraine against the background of the pandemic and economic crisis are highlighted. Roadmap for overcoming the crisis presents innovative tools based on cognitive technologies such as neuromarketing, mobile marketing, blog marketing, event marketing, branding, as well as diversification of tourism entities, proposed to support small and medium-sized businesses operating in the tourism sector that have suffered the most from coronavirus measures. This article summarizes and analyses the successful examples of implementation of these tools for tourism enterprises in Ukraine and the world. It is concluded that the main condition to overcome the crisis, to develop successful tourism destinations, and to create sustainable development is the collaboration between businesses, community, and policymakers.

The wide dispersion of the properties of plant fiber bundles further limits their use. In this study, manual and retting methods were used to extract fiber bundles from the available and underutilized Ananas comosus (AC) leaf waste in Cameroon. These fibers were sampled in three zones: base, middle and head. The fibers extracted by retting in the different zones were found to have better thermal stability. A 2.5% solution of sodium hypochlorite was used for bleaching the various pineapple fibers. Density, fineness, functional groups, mechanical properties, water absorption and morphology of different fibers were characterized. Density and fineness decreased from the head to the base of the leaf and were lower for manually obtained fiber bundles. The peaks of the infrared spectra associated with the functional groups of the pineapple fibers change very little along with the leaf but are clearly more pronounced for the fibers extracted manually. Fibers in the middle of the leaf have been found to have slightly better mechanical and water absorption properties. All fiber bundles can rapidly absorb water following simple exponential kinetics. Bleaching partially removes non-cellulosic materials from the fibers with a transverse shrinkage effect, which improves their fineness, density and hydrophilic function. Unfortunately, it reduces their tensile strength and fracture toughness. These results show that the whole leaf can be used without restriction to extract manually or by retting the fiber bundles intended for the manufacture of textiles and composites. Furthermore, bleaching with sodium hypochlorite seems ineffective due to fiber degradation.

Plastics are widely used in every part of life. Microplastics (MPs) are classified as emerging contaminants in nature. Yet, microplastic transportation parameters in groundwater are not characterized well. In this study, microplastic transport in saturated homogeneous media was investigated. For this purpose, one-dimensional column tests were performed using the fluorescent and microplastic tracers to figure out the hydrodynamic conditions for the microplastic transport. Large silica, small silica, sand, and coarse gravel were the tested media. The hydrodynamic transport parameters were calculated by inverse solution methodology using the experimental and the analytical solution results. Only the coarse gravel medium with a minimum 1 mm and maximum 20 mm (5 mm of median) pore sizes and kinematic porosity 40.2% were found to be suitable for the transport of the used polyethylene (PE) whose particle size was between 200 and 500 µm. It is not possible to transport PE particles of selected size from fine-grained media. Transportation occurred in coarse-grained media such as coarse gravel. The calculated dispersivity values for the coarse gravel were 2.58 and 3.02 cm by using fluorescent and PE tracers, respectively. The experiments showed that the used PE particles cannot be transported if the mean flow velocity is lower than 2.02 cm/min in the coarse gravel medium. The microplastic accumulation might be an issue for an actual aquifer rather than the transportation of it considering the actual groundwater flow velocity is generally much lower.

Abstract Background Air pollution is one of the world’s leading mortality risk factors contributing to seven million deaths annually. COVID-19 pandemic has claimed about one million deaths in less than a year. However, it is unclear whether exposure to acute and chronic air pollution influences the COVID-19 epidemiologic curve. Methods We searched for relevant studies listed in six electronic databases between December 2019 and September 2020. We applied no language or publication status limits. Studies presented as original articles, studies that assessed risk, incidence, prevalence, or lethality of COVID-19 in relation with exposure to either short-term or long-term exposure to ambient air pollution were included. All patients regardless of age, sex and location diagnosed as having COVID-19 of any severity were taken into consideration. We synthesised results using harvest plots based on effect direction. Results Included studies were cross-sectional (n = 10), retrospective cohorts (n = 9), ecological (n = 6 of which two were time-series) and hypothesis (n = 1). Of these studies, 52 and 48% assessed the effect of short-term and long-term pollutant exposure, respectively and one evaluated both. Pollutants mostly studied were PM2.5 (64%), NO2 (50%), PM10 (43%) and O3 (29%) for acute effects and PM2.5 (85%), NO2 (39%) and O3 (23%) then PM10 (15%) for chronic effects. Most assessed COVID-19 outcomes were incidence and mortality rate. Acutely, pollutants independently associated with COVID-19 incidence and mortality were first PM2.5 then PM10, NO2 and O3 (only for incident cases). Chronically, similar relationships were found for PM2.5 and NO2. High overall risk of bias judgments (86 and 39% in short-term and long-term exposure studies, respectively) was predominantly due to a failure to adjust aggregated data for important confounders, and to a lesser extent because of a lack of comparative analysis. Conclusion The body of evidence indicates that both acute and chronic exposure to air pollution can affect COVID-19 epidemiology. The evidence is unclear for acute exposure due to a higher level of bias in existing studies as compared to moderate evidence with chronic exposure. Public health interventions that help minimize anthropogenic pollutant source and socio-economic injustice/disparities may reduce the planetary threat posed by both COVID-19 and air pollution pandemics.

Whether chronic inflammation contributes to metabolic disease through the dysregulation of circadian systems remains incompletely understood in humans. Here the authors show that circadian clock function is perturbed in adipose tissue from individuals with obesity, and that inhibition of NFkB improves clock function.

Abstract Telomere length (TL) is a marker of ageing and mitochondrial DNA (mtDNA) is an early marker of inflammation caused by oxidative stress. We determined TL and mtDNA content among active pulmonary tuberculosis (PTB) patients to assess if these cellular biomarkers differed between artisanal miners and non-miners, and to assess if they were predictive of treatment outcome. We conducted a prospective cohort study from August 2018 to May 2019 involving newly diagnosed PTB patients at three outpatient TB clinics in a rural Democratic Republic of Congo. We measured relative TL and mtDNA content in peripheral blood leukocytes (at inclusion) via qPCR and assessed their association with PTB treatment outcome. We included 129 patients (85 miners and 44 non-miners) with PTB (median age 40 years; range 5–71 years, 22% HIV-coinfected). For each increase in year and HIV-coinfection, TL shortened by − 0.85% (− 0.19 to − 0.52) (p ≤ 0.0001) and − 14% (− 28.22 to − 1.79) (p = 0.02) respectively. Independent of these covariates, patients with longer TL were more likely to have successful TB treatment [adjusted hazard ratio; 95% CI 1.27 for a doubling of leucocyte telomere length at baseline; 1.05–1.44] than patients with a shorter TL. Blood mtDNA content was not predictive for PTB outcome. For a given chronological age, PTB patients with longer telomeres at time of diagnosis were more likely to have successful PTB treatment outcome.

OBJECTIVES: Fiberglass-reinforced plastics (FRP) manufacturing has been related to cases of severe airway obstruction and elevated risk of respiratory mortality. But the specific job content risk is not clear. This study evaluated the respiratory health effects of the FRP lamination process. METHODS: A questionnaire was used to evaluate respiratory symptoms of workers in two yacht-building plants. Pre-shift (07:30–08:30 hours) and post-shift (17:00–18:00 hours) lung function was measured, while post-shift induced sputum was collected on the first day of the week. The participants were grouped into FRP laminators and non-laminators. Linear and logistic regression was used to investigate the effects of the lamination process on lung function. RESULTS: Laminators had a higher prevalence of chronic cough, lower pre-shift forced expiratory volume in first second (FEV1) and FEV1/force vital capacity (FVC) (-3.3% and -1.5%), lower post-shift FVC and FEV1 (-3.6% and -4.9%), and larger post-shift reduction of FVC (-2.1%) compared to non-laminators. The laminators also had higher risk of early obstructive and overall (obstructive plus restrictive) lung function impairment, and post-shift reduction of FVC >10% [odds ratio (OR) 5.98, 4.98, and 3.87, respectively). They also had higher percentages of neutrophils and lymphocytes in the induced sputum. CONCLUSION: Laminators should undergo regular check-ups of respiratory symptoms and lung function. Further toxicologic studies are warranted to identify the specific causal agent in the FRP lamination process.

Arms races between herbivores and plants have likely affected their evolutionary histories, which could have led to their high diversity. Allio et al. find that butterflies shifting to new host plants have more adaptive molecular signatures across their genomes and show repeated bursts of speciation rates.

Domestic cleaners have an increased risk of asthma-like and other respiratory symptoms and conditions. Uncertainty exists about which products are most hazardous. We aimed to investigate, among professional domestic cleaners, the associations of ocular/respiratory outcomes with using specific types of products at work and with the ability to choose their own products.Among domestic cleaners employed by “service vouchers” companies in Belgium, we administered an online questionnaire on ocular/respiratory symptoms (frequency and time relation to workdays), frequency of use of 40 types of products, and ability to choose one’s own products. Work-relatedness was defined as symptoms improving/disappearing on days off-work. We studied associations between frequency of product-use with work-related outcomes (eye irritation, rhinitis symptoms, sore throat, laryngeal symptoms, asthma symptoms, cough) and with chronic bronchitis, using multivariable logistic and elastic net regression. Adjusted odds ratios (OR) with 95%-confidence intervals were obtained per time a product was used per week.Among 1,586 domestic cleaners (99% women), the number of times sprays were used (median 13/week) was significantly associated with all outcomes (ORs between 1.012 and 1.024 per time sprays were used per week). Bleach/disinfectant-containing liquid products were associated with all outcomes, except for laryngeal symptoms (ORs 1.086 to 1.150); ammonia with work-related upper airway symptoms and chronic bronchitis. Cleaners able to choose their own products had fewer work-related eye symptoms (OR 0.728;0.556–0.954), rhinitis (OR 0.735;0.571–0.946) and cough (OR 0.671;0.520–0.865). Using elastic net regression, work-related rhinitis was most strongly associated with mould removal spray (OR 1.108;1.006–1.248), carpet/seat/curtain spray (OR 1.099;1.001–1.304) and ammonia (OR 1.081;1.002–1.372); work-related asthma with carpet/seat/curtain spray (OR 1.103;1.017–1.322), mould removal spray (OR 1.029;0.995–1.199) and drain cleaner (OR 1.023;0.979–1.302).In a large group of domestic cleaners, we documented that cleaning products have a range of adverse respiratory effects. Empowering cleaners to choose their products may reduce the burden of symptoms.

Abstract Background Nyamulagira and Nyiragongo are active volcanoes situated close to Goma (North Kivu, Democratic Republic of Congo). These volcanoes are among the most prolific sources of volcanic SO2 pollution on earth. Objective We investigated the possible spatiotemporal relationships between volcanic degassing represented by eruptive emissions of SO2 that occurred between 2000 and 2010, and the incidence of acute respiratory symptoms (ARS) in populations living in areas up to more than 100 km from the volcanoes. Methodology The total flux of SO2 emitted during eruptions since 2000 and the average spatial distribution of the volcanic plume (2004–2008) were based on publicly available remote sensing data. The monthly numbers of adults and children reporting acute respiratory symptoms were extracted from health data collected routinely by selected local health centres and hospitals between 2000 and 2010. The monthly numbers of persons with ARS recorded during or after eruptions were compared with those recorded before eruptions, using negative binomial regression models allowing the calculation of incidence rate ratios (IRR) and their 95% confidence intervals. We first compared years with and without eruptions and then considered shorter time-windows (months). Results In the investigated area, ARS were the second most frequent cause of medical visits (12.2%, n = 3.2 million cases), after malaria (32.3%, n = 8.4 million cases). SO2 emissions gradually increased 30 to 50 times in 2010 compared to 2002. Taking 1999 as a reference, the IRR for ARS increased three-fold between 2000 [0.9 (0.8, 1.1)] and 2009 [2.8 (2.2, 3.7)]. Although the incidence of ARS appeared to increase after some eruptions, especially in areas close (

Abstract Background Plagiarism is considered as serious research misconduct, together with data fabrication and falsification. However, little is known about biomedical researchers’ views on plagiarism. Moreover, it has been argued – based on limited empirical evidence – that perceptions of plagiarism depend on cultural and other determinants. The authors explored, by means of an online survey among 46 reputable universities in Europe and China, how plagiarism is perceived by biomedical researchers in both regions. Methods We collected work e-mail addresses of biomedical researchers identified through the websites of 13 reputable universities in Europe and 33 reputable universities in China and invited them to participate in an online anonymous survey. Our questionnaire was designed to assess respondents’ views about plagiarism by asking whether they considered specific practices as plagiarism. We analyzed if respondents in China and Europe responded differently, using logistic regression analysis with adjustments for demographic and other relevant factors. Results The authors obtained valid responses from 204 researchers based in China (response rate 2.1%) and 826 researchers based in Europe (response rate 5.6%). Copying text from someone else’s publication without crediting the source, using idea(s) from someone else’s publication without crediting the source and republishing one’s own work in another language without crediting the source were considered as plagiarism by 98, 67 and 64%, respectively. About one-third of the respondents reported to have been unsure whether they had been plagiarizing. Overall, the pattern of responses was similar among respondents based in Europe and China. Nevertheless, for some items significant differences did occur in disadvantage of Chinese respondents. Conclusions Findings indicate that nearly all biomedical researchers understand (and disapprove of) the most obvious forms of plagiarism, but uncertainties and doubts were apparent for many aspects. And the minority of researchers who did not recognize some types of plagiarism as plagiarism was larger among China-based respondents than among Europe-based respondents. The authors conclude that biomedical researchers need clearer working definitions of plagiarism in order to deal with grey zones.

BackgroundParkinson disease is a neurodegenerative disease causing a progressive loss of autonomy. This requires long-term rehabilitation care. Currently, new technologies are being developed for use in daily life, and there is a progressive implementation of telerehabilitation. ObjectiveThe aim of this study (the TELEP@RK study) is to evaluate the uses of a digital self-rehabilitation device in patients with Parkinson disease and their independent physiotherapists on the scale of a health territory. MethodsA total of 10 independent physiotherapists and 31 patients with Parkinson disease were followed for 1 year to evaluate the use of a telerehabilitation tool (digital tablet and inertial sensor) via questionnaires of the Unified Theory of Acceptance and Use of Technology (UTAUT). The questionnaires were submitted to participants at 0, 2, and 12 months from the start of follow-up. The averages of the scores of the different determinants and constructs of the UTAUT questionnaires were compared at the different follow-up times. ResultsAmong professionals, the averages of the various determinants were generally high at the beginning of the study with an average (out of 5) performance expectancy of 4.19, effort expectancy of 3.88, social influence of 3.95, facilitating conditions of 4, and intention to use of 3.97. These averages decreased over time. ConclusionsAcceptability, acceptance, and appropriation of the tool were very high among the physiotherapists as well as the patients, despite the tool’s lack of evolution during the study. In the current health care context, these results allow us to envision a new organization of the care pathway for patients with chronic diseases, with the increased use of new technologies associated with telecare.

The C-terminus of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) protein E contains a PBM (PDZ-binding motif) targeting PDZ (PSD-95/Dlg/ZO-1) domains, which is identical to the PBM of SARS-CoV. The latter is involved in the pathogenicity of the virus. Recently, we identified 10 human PDZ-containing proteins showing significant interactions with SARS-CoV-2 protein E PBM. We selected several of them involved in cellular junctions and cell polarity (TJP1, PARD3, MLLT4, and LNX2) and MPP5/PALS1 previously shown to interact with SARS-CoV E PBM. Targeting cellular junctions and polarity components is a common strategy by viruses to hijack cell machinery to their advantage. In this study, we showed that these host PDZ domains TJP1, PARD3, MLLT4, LNX2, and MPP5/PALS1 interact in a PBM-dependent manner in vitro and colocalize with the full-length E protein in cellulo, sequestrating the PDZ domains to the Golgi compartment. We solved three crystal structures of complexes between human LNX2, MLLT4, and MPP5 PDZs and SARS-CoV-2 E PBM highlighting its binding preferences for several cellular targets. Finally, we showed different affinities for the PDZ domains with the original SARS-CoV-2 C-terminal sequence containing the PBM and the one of the beta variant that contains a mutation close to the PBM. The acquired mutations in the E protein localized near the PBM might have important effects both on the structure and the ion-channel activity of the E protein and on the host machinery targeted by the variants during the infection.

Repeated use of the same drill bit during drilling wears off the cutting edges, which can lead to a significant increase in heat as a result of friction, which is harmful to a bone above 55 °C. Few previous studies have examined the effects of using the same drill bit several times, on temperature. The objective of this study was to determine the effect of each drilling on temperature and force. 72 trials were performed. A total of 24 stainless steel drill bits of ∅3.2 mm were used to drill bovine bone samples. Each drill bit was used at least 3 times. T thermocouples were used to measure temperatures during each drilling test. Possible correlations of cutting parameters were studied. Tests were performed on a test rig measuring forces and temperatures during drilling. Effects of spindle speed (N), feed rate (Vf), and several trials (E) on temperature and forces were measured. Images of the drill bits were analyzed by digital microscopy before and after the drilling series for signs of wear. Temperatures increased significantly from E1 to E3. They decreased moderately with Vf. The best cutting conditions were at N = 200 rpm for Vf = 60 mm/min and N = 100 rpm for Vf = 30 mm/min drilling. At N > 200 rpm, they were very high. Temperature rise is significantly related to number of drilling (E), spindle speed (N), and inversely to feed rate (Vf). Analysis of images by digital microscopy confirmed drill bits wearing off, following the number of trials.

Background. Environmental pollution by trace metals is of concern in the African Copperbelt, a region of intense mining situated on either side of the border between the Democratic Republic of Congo (DRC) and Zambia. Scientists from both countries undertook a collaborative study using the same sampling and analytical methodologies to assess metal contamination of water and food in both countries.Methods. In six mining areas (Lubumbashi, Likasi, Kipushi in DRC; Chingola, Kitwe, Luanshya in Zambia) samples of water (surface, boreholes, taps) and various crops were collected in two residential sites near mining operations, and in rural villages farther away (controls). Nine elements (Mn, Co, Ni, Cu, Zn, As, Cd, Pb, U) were measured by ICP-MS or ICP-OES.Results. In drinking water obtained close to mining, the median concentrations (µg/L) of all trace elements, except Zn, were substantially higher in DRC (n=20) than Zambia (n=18), this being most pronounced for Pb (27 vs 0.08), Cd (0.7 vs

As part of a broader multidisciplinary research project dealing with the association between health and green/blue environments, this paper aims at exploring the spatial variation of medication reimbursements within Belgium. These data were potentially and a priori considered as a proxy for health. This paper is purely exploratory: statistical maps, correlations, PCAs and cluster analyses corroborate the results. Five groups of medications prescribed for health disorders associated with the environment have been selected. We show that – at the level of the municipalities – the spatial distributions of the five medication groups are positively correlated to each other (medication consumption co-vary positively in space, whatever their type), but are independent of the environmental and socio-economic conditions measured. Against our expectation, they prove to be negatively correlated to air pollution and green spaces. Strikingly, the spatial distribution of medication prescriptions follows the linguistic border between Flanders and Wallonia. This implies that the observed differences are mainly due to administrative/political regional differences in terms of health policies, medical schools, pharmaceutical commercial activities, etc. that are hard to quantify (no data, diversity of actors) but should be taken into account in any further explanatory model. Medication reimbursements data correspond to a new type of data, and despite their potential attractiveness for health analyses, extreme care has to be taken when interpreting their spatial variation and their link to health.

Measurements of thermal conductivity with the heat flow meter, laser flash method, hot disk method and hot wire method are compared on two kinds of refractory materials: Insulating Boards and Insulating Fireclay Bricks. Heat losses, humidity, anisotropy and heterogeneity can explain the variation in thermal conductivity values obtained with the different techniques. If they are taken into account in the analysis, discrepancy within 10% can be found. The choice of the technique depends on the investigated material and on the level of information required.