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Source apportionment of PM2.5 oxidative potential in an East Mediterranean site
No full textInternational audienceThe East Mediterranean is the third region with the highest ambient and household air pollution attributable death rate, with an average of 125 per 100,000 population in 2016. This number could tend to rise in the future with the increase of aerosol concentrations due to climate change . These high concentrations of PM result mainly from transported pollution mixed with anthropogenic emissions (road traffic, industrial, and residential emissions), and natural emissions (Saharan and African deserts) . Therefore, it is crucial to determine the pollution sources and the species that contribute the most to the toxicity in order to develop efficient air quality strategies.The objectives of this work are to study the relationship between oxidative potential (OP) results and the PM2.5 chemical components, and to conduct a source apportionment of PM2.5 OP by coupling PMF results and multiple linear regression models. PM2.5 samples were collected for almost a year in Zouk Mikael (ZK), an urban site under industrial influence in Lebanon. ZK is characterized by the biggest power plant in the country which runs on heavy fuel oil, a high density of population (4,200 inhabitants/km2) along with high road traffic and the use of diesel generators for electricity generation. These samples were characterized for their carbonaceous fraction, water-soluble ions, elements, and organic species. Several tracer compounds were gathered in the PMF model to assess the contribution of the sources to PM2.5. Additionally, the oxidative properties of PM components were studied using the OP with two acellular methods: the ascorbic acid (AA) and the dithiothreitol (DTT) assays. The mean volume normalized OP-AAv value was 0.64 ± 0.29 nmol.min¬-1.m-3 and the mean OP-DTTv was 0.49 ± 0.32 nmol.min-1.m-3. Spearman correlations revealed strong correlations between OP-AAv and the carbonaceous fraction as well as organic compounds while OP-DTTv seemed to be more correlated with elements emitted from different anthropogenic activities. The apportionment of OP showed that local anthropogenic sources such as biomass burning (26% of OP-AAv and 10% of OP-DTTv), vehicular emissions (20% and 19%), and heavy fuel oil combustion (23% and 33%) contribute the most to the OP-AAv and OP-DTTv, respectively . The contribution of biomass burning in winter to OP was at least 33 times higher compared to summer while the highest contribution between the sources was found for HFO combustion during summer
The Contribution of Various In Vitro Methodologies to Comprehending the Filling Ability of Root Canal Pastes in Primary Teeth
No full textA void-free obturation during root canal treatment on primary teeth is currently very difficult to attain. In this study, the pulpectomy filling abilities of Bio-C Pulpecto (Angelus, Basil, Londrina, Paraná, Brazil) and of zinc oxide eugenol, or "ZOE" (DenPro, Prevest, New York, NY, USA), were compared using several in vitro techniques. Therefore, 30 primary anterior teeth were used in the present in vitro study. Analysis of variance (ANOVA), including a multiple comparison procedure (Holm-Sidak method, Dunn's Method, or Tukey test), was used. On micro-CT, Bio-C Pulpecto exhibited higher void percentages than did ZOE (10.3 ± 3.8%, and 3.5 ± 1.3%), respectively (p < 0.05). With digital microscopy, higher total void percentages were found in the BC (13.2 ± 26.7%) group compared to the ZOE (2.7 ± 2.8%) group (p < 0.05). With the CLSM, mean tubular penetration depths were higher for Bio-C Pulpecto than for ZOE in all canal thirds (p < 0.05). SEM images demonstrated no tags into dentinal tubules in either group throughout the three thirds. Moreover, higher statistically significant flowability was found for Bio-C (2.657 ± 0.06 mm) compared to ZOE (1.8 ± 0.13 mm) (p < 0.05). The findings of this study indicate that neither ZOE nor Bio-C Pulpecto appears to meet the criteria for an ideal root canal filling paste for primary teeth. This study laid the groundwork for future research by determining how micro-CT, digital microscopy, SEM, and CLSM contribute to our understanding of the filling process of primary teeth. More thorough research on the mechanism of root canal obturation on primary teeth is required to achieve a long-term successful root canal therapy in young children
Effects of Biscriptuality on Graphomotor Coordination Dynamics
No full textInternational audienceBiscriptuality is the ability to write in two different writing systems. The aim of this study was toexamine the effects of biscriptuality on graphomotor coordination dynamics in right-handed adults.Thirty-four French monoscriptuals and 34 French-Arabic biscriptual participants traced series of loopsin two writing directions, and in two directions of rotation. We found that biscriptuals displayed ageneral advantage over monoscriptuals in terms of tracing frequency, while both groups displayed apreference for the left to right direction. These results provide novel evidence on the effects of writingdirection and type of expertise on graphomotor performance by showing that biscriptuality could be anasset
Differences in Kinematic Changes From Self-Selected to Fast Speed Gait in Asymptomatic Adults With Radiological Signs of Femoro-Acetabular Impingement
No full textInternational audienceFemoro-acetabular impingement (FAI) may present as alterations in the skeletal morphology of the hip. Repercussions of FAI can be witnessed in self-selected speed walking as well as physical exercise such as running or fast speed walking. The aim of this study was to investigate changes in kinematics at different gait speeds in subjects presenting with radiological findings invoking FAI. One hundred thirty asymptomatic adults underwent biplanar X-rays with a calculation of 3D hip parameters: acetabular anteversion, abduction and tilt, vertical center edge angle (VCE), femoral anteversion, neck-shaft angle, acetabular coverage of the femoral head, femoral head diameter and neck length. Parameters were classified according to FAI clinical thresholds. Two groups were created: Control group (63 subjects having up to one subnormal hip parameter in favour of FAI) and Radiographic FAI group (67 subjects having ≥2 subnormal hip parameters that might cause FAI). All subjects underwent 3D gait analysis at self-selected and fast speed, from which kinematic parameters were generated. Arithmetic differences between fast and self-selected speed gait were considered as gait changes. Subjects in the Radiographic FAI group had decreased acetabular tilt (24 vs. 19˚), anteversion (19 vs. 16˚), abduction (55 vs. 53˚), femoral anteversion (18 vs. 14˚) and increased VCE (29 vs. 33˚, all p<0.05), compared to controls. Changes from self-selected to fast speed showed that subjects in the Radiographic FAI group had lower range of motion (ROM) pelvic rotation (7 vs. 4˚) and ROM hip flexion/extension (10 vs. 7˚), reduced hip extension (-4 vs. -2˚) and step length (16 vs. 13 cm; all p<0.05). The Radiographic FAI group had decreased acetabular abduction, anteversion and femoral anteversion in favour of FAI. When adapting from self-selected to fast speed gait, the Radiographic FAI group seemed to limit pelvic rotation and hip flexion/extension resulting in a decrease in step length. These kinematic limitations were previously reported in subjects with symptomatic FAI. Gait analysis could be considered as a functional diagnostic tool to assess FAI along with radiological assessment
Combined gait analysis and radiologic examination in children with X-linked hypophosphatemia
No full textInternational audienceBackground: X-linked hypophosphataemia causes bone deformities and gait abnormalities that tend to worsen with age in the absence of appropriate treatment. However, doctors do not currently use quantitative tools to characterize these symptoms and their possible interactions.Methods: Radiographs and 3D gait data from 43 non-surgical growing children with X-linked hypophosphataemia were acquired prospectively. Data from age-matched typically developing children were used to form the reference group. Subgroups based on radiological parameters were compared with each other and with the reference population. Linear correlations between radiographic parameters and gait variables were examined.Finding: X-linked hypophosphatemic patients differed from the control group in pelvic tilt, ankle plantarflexion, knee flexion moment and power. High correlations with tibiofemoral angle were found for trunk lean, knee and hip adduction, and knee abduction moment. The Gait Deviation Index was below 80 for 88% of the patients with a high tibiofemoral angle (varus). Compared to other subgroups, varus patients had augmented trunk lean (+3°) and knee adduction (+10°) and decreased hip adduction (-5°) and ankle plantarflexion (-6°). Femoral torsion was associated with alterations in rotation at the knee, and hip.Interpretation: Gait abnormalities induced in X-linked hypophosphataemia have been described in a large cohort of children. Links between gait alterations and lower limb deformities were found, with varus deformities standing out. Since bony deformities appear when X-linked hypophosphatemic children start walking and have been found to alter gait patterns, we suggest that combining radiology with gait analysis may improve the clinical management of X-linked hypophosphataemia
Femoral neck version in the spinopelvic and lower limb 3D alignment: a full-body EOS® study in 400 healthy subjects
No full textInternational audienceBackground: The goal of this study was to better understand the variation of femoral neck version according to spinopelvic and lower limb 3D alignment using biplanar X-rays in standing position.Methods: This multicentric study retrospectively included healthy subjects from previous studies who had free-standing position biplanar radiographs. Subjects were excluded if they presented spinal or any musculo-skeletal deformity, and reported pain in the spine, hip or knee. Age, sex, and the following 3D-reconstructed parameters were collected: spinal curvatures, pelvic parameters, sagittal vertical axis (SVA), T1 pelvic angle (TPA), spino-sacral angle (SSA), femoral torsion angle (FTA), sacro-femoral angle (SFA), knee flexion angle (KA), ankle angle (AA), pelvic shift (PS) and ankle distance. Femoral neck version angle (FVA) was calculated between horizontal plane projection of the bi-coxo-femoral axis and the line passing through the femoral neck barycenter and femoral head center. Analysis according to age subsets was performed.Results: A total of 400 subjects were included (219 females); mean age was 29 ± 18 years (range: 4-83). Subjects with high pelvic tilt values presented significantly higher FVA than average and low-PT individuals, respectively, 7.8 ± 7.1°, 2 ± 9° and 2.1 ± 9.5° (p < 0.001). These subjects also presented lower lumbar lordosis values and higher acetabulum anteversion in the horizontal plane than the two other groups. SVA correlation with FVA was weaker (r = 0.1, p = 0.03) than SSA and TPA (r = - 0.3 and r = 0.3, respectively, p < 0.001). A strong correlation was found with femoral torsion (r = 0.5, p < 0.001). SFA (r = - 0.3, p < 0.001), pelvic shift (r = 0.2, p < 0.001) and ankle distance (r = 0.3, p < 0.001) were also significantly correlated. Multivariate analysis confirmed significant association of age, pelvic tilt, lumbar lordosis, pelvic shift, ankle distance and femoral torsion with FVA.Conclusion: Patients with lower lumbar lordosis present pelvic retroversion which induces a higher femoral neck version. This finding may help positioning implants in total hip replacement procedures. Higher pelvic shift, age, male gender and increased femoral torsion were also correlated with higher FVA
Biochemical limitations of Bacillus thuringiensis based biopesticides production in a wheat bran culture medium
No full textInternational audienceBacillus thuringiensis, a gram-positive sporulating bacteria found in the environment, produces, during its sporulation phase, crystals responsible for its insecticidal activity, constituted of an assembly of pore-forming δ-endotoxins. This has led to its use as a biopesticide, an eco-friendly alternative to harmful chemical pesticides. To minimize production cost, one endemic Bacillus thuringiensis sv. kurstaki (Btk) strain Lip, isolated from Lebanese soil, was cultivated in a wheat bran (WB) based medium (IPM-4-Citrus project EC n° 734921). With the aim of studying the biochemical limitations of Btk biopesticide production in a wheat bran based medium, the WB was sieved into different granulometries, heat treated, inoculated with Btk Lip at flask scale, then filtered and separated into an insoluble and a permeate fractions. Several biochemical analyses, ie. bio performances, starch, elemental composition, total nitrogen and ashes, were then conducted on both fractions before and after culture. On a morphological level, two populations were distinguished, the fine starch granules and the coarse lignocellulosic particles. The biochemical analyses showed that both the raw and sieved WB have a similar proteins content (0.115 g/gdm WB), water content (0.116 g/gdm WB) and elemental composition (carbon: 45%, oxygen: 37%, nitrogen: 3%, hydrogen: 6%, ashes: 5%). The starch content was 17%, 14% and 34% and the fermentable fraction was estimated to 32.1%, 36.1% and 51.1% respectively for classes 2, 3 and 4. Both the elemental composition and Kjeldahl analyses showed that the nitrogen is the limiting nutrient of the culture
Profiles of Parental Burnout Around the Globe: Similarities and Differences Across 36 Countries
No full textInternational audienceParental burnout (PB) is a pervasive phenomenon. Parenting is embedded in cultural values, and previous research has shown the role of individualism in PB. In this paper, we reanalyze previously collected data to identify profiles based on the four dimensions of PB, and explore whether these profiles vary across countries’ levels of collectivistic-individualistic (COL-IND) values. Our sample comprised 16,885 individuals from 36 countries (73% women; 27% men), and we used a latent profile approach to uncover PB profiles. The findings showed five profiles: Fulfilled, Not in PB, Low risk of PB, High risk of PB and Burned out. The profiles pointed to climbing levels of PB in the total sample and in each of the three country groups (High COL/Low IND, Medium COL-IND, Low COL/High IND). Exploratory analyses revealed that distinct dimensions of PB had the most prominent roles in the climbing pattern, depending on the countries’ levels of COL/IND. In particular, we found contrast to be a hallmark dimension and an indicator of severe burnout for individualistic countries. Contrary to our predictions, emotional distance and saturation did not allow a clear differentiation across collectivistic countries. Our findings support several research avenues regarding PB measurement and intervention
Estimating urban seismic damages and debris from building-level simulations: Application to the city of Beirut, Lebanon
No full textInternational audienceThe estimation of seismic damages and debris at the urban scale-at a building-by-building level-is challenging for several reasons. First, commonly used methodologies for seismic damage estimation rarely take into account the local site effects, precisely at the building-level. Second, the available methods for debris estimation fail to estimate at the same time the quantity of debris generated per building according to its damage level and the distribution of the debris (extent and height) around buildings. Finally, the lack of comprehensive data on the building stock and the relevant building properties and their taxonomy further increases the complexity of assessing possible earthquake consequences at an urban scale. This paper addresses these challenges and proposes improvements to the assessment of seismic damages and debris from building-level simulations, along with the development of a 3D building model based on satellite images and heterogeneous data. These developments