Some remarks on the dating of 12 Old Kingdom tombs at Giza

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Safer injections following a new national medicine policy in the public sector, Burkina Faso 1995 – 2000

BACKGROUND: The common failure of health systems to ensure adequate and sufficient supplies of injection devices may have a negative impact on injection safety. We conducted an assessment in April 2001 to determine to which extent an increase in safe injection practices between 1995 and 2000 was related to the increased access to injection devices because of a new essential medicine policy in Burkina Faso. METHODS: We reviewed outcomes of the new medicine policy implemented in1995. In April 2001, a retrospective programme review assessed the situation between 1995 and 2000. We visited 52 health care facilities where injections had been observed during a 2000 injection safety assessment and their adjacent operational public pharmaceutical depots. Data collection included structured observations of available injection devices and an estimation of the proportion of prescriptions including at least one injection. We interviewed wholesaler managers at national and regional levels on supply of injection devices to public health facilities. RESULTS: Fifty of 52 (96%) health care facilities were equipped with a pharmaceutical depot selling syringes and needles, 37 (74%) of which had been established between 1995 and 2000. Of 50 pharmaceutical depots, 96% had single-use 5 ml syringes available. At all facilities, patients were buying syringes and needles out of the depot for their injections prescribed at the dispensary. While injection devices were available in greater quantities, the proportion of prescriptions including at least one injection remained stable between 1995 (26.5 %) and 2000 (23.8 %). CONCLUSION: The implementation of pharmaceutical depots next to public health care facilities increased geographical access to essential medicines and basic supplies, among which syringes and needles, contributing substantially to safer injection practices in the absence of increased use of therapeutic injections

Transforming growth factor-β employs HMGA2 to elicit epithelial–mesenchymal transition

Epithelial–mesenchymal transition (EMT) occurs during embryogenesis, carcinoma invasiveness, and metastasis and can be elicited by transforming growth factor-β (TGF-β) signaling via intracellular Smad transducers. The molecular mechanisms that control the onset of EMT remain largely unexplored. Transcriptomic analysis revealed that the high mobility group A2 (HMGA2) gene is induced by the Smad pathway during EMT. Endogenous HMGA2 mediates EMT by TGF-β, whereas ectopic HMGA2 causes irreversible EMT characterized by severe E-cadherin suppression. HMGA2 provides transcriptional input for the expression control of four known regulators of EMT, the zinc-finger proteins Snail and Slug, the basic helix-loop-helix protein Twist, and inhibitor of differentiation 2. We delineate a pathway that links TGF-β signaling to the control of epithelial differentiation via HMGA2 and a cohort of major regulators of tumor invasiveness and metastasis. This network of signaling/transcription factors that work sequentially to establish EMT suggests that combinatorial detection of these proteins could serve as a new tool for EMT analysis in cancer patients

Lack of transparency and social participation undermine the fight against deforestation in Brazil

The Brazilian government wrapped up 2021 with a masquerade at COP26  (26th UN Climate Change Conference of the Parties): hiding PRODES (the annual Amazon deforestation report). After three years of denying and dismantling the public apparatus to fight Amazon deforestation, this is emblematic of how transparency and social participation have been neglected. Transparency of PRODES has been crucial to all initiatives against deforestation. Notwithstanding, the Brazilian government has not only worked to discredit PRODES, but limited access to other environmental data and decreed a ‘gag law’. Responses to requests of public data are largely unsatisfactory and information on deforestation permits (key to understanding the extent of legal and illegal deforestation) is either missing or incomplete. Social participation has been strongly limited after one-fifth of 22 national boards monitoring the public administration was extinct and almost half restructured. As an outcome, the Amazon Fund, the most important source of financial support against deforestation, was frozen. These systemic problems compromise the political struggle to combat Amazon deforestation and worsen the living conditions of those peoples protecting forests. Increasing transparency of environmental data through robust and reliable mechanisms, and ensuring social participation in the decision-making processes are crucial to halt deforestation and support Brazil’s role as an international player

Damage Analysis of a Ferritic SiMo Ductile Cast Iron Submitted to Tension and Compression Loadings in Temperature

Tensile and compression tests were carried out on a ductile cast iron for temperatures up to 1073 K. The damage caused inside and around graphite nodules was evaluated as a function of the local equivalent plastic strain by using microstructural quantifications. The mechanical properties are strongly dependent on a temperature above 773 K. Concerning tensile behavior, an evolutional law issued from the Gurson model representing the void growth as a function of the deformation and temperature was successfully employed. It is demonstrated that the strain state and the temperature have a strong influence on the void growth function. In the case of compression tests, the temperature has a weak influence on the nodule deformation for temperatures lower than 773 K, and the mechanical behavior is driven by the viscoplastic properties of the ferrite. For higher temperatures, the mechanical properties in compression are progressively modified, since graphite nodules tend to remain spherical, and ferrite grains are severely deformed. A synthesis of the damage mechanisms is proposed in the studied range of temperature and plastic strain. It appears that the graphite nodule aspect ratio can be used as an indicator of the deformation under compression loading for temperatures ranging from room temperature to 673 K

Investigation of the internal structure of flax fibre cell walls by transmission electron microscopy

The development of the use of flax fibre as reinforcement of eco-friendly composite materials requires a good knowledge of its hydrothermal and mechanical behaviours. To this end the fibre internal structure must be finely investigated. Transmission electron microscopy was used to analyse the morphology of the fibre cell walls in terms of the arrangement of the layers and their thickness. Thus, an alternative eco-friendly staining method, based on oolong tea extract was successfully implemented. The results reveal an arrangement at the nanoscale slightly different from the classical four layer model encountered in the literature: the inner layer includes three to four sub-layers. The cell walls comprises two outer layers of relative thickness of about 10 %, a middle layer of about 70 % and a group of thinner layers (called sub-layers) that are contiguous to the lumen with relative thickness of about 20 %

3D individual based model for simultaneous growth and interaction of L. Monocytogenes and lactic acid bacteria

International audienceBy interacting with pathogens, lactic acid bacteria (LAB) are able to contribute to food safety. By means of their lactic acid production which induces pH decrease, LAB influence the growth of pathogens. The aim of this study is to model and simulate lactic acid production, pH evolution, according to carbohydrate concentration in media, temperature, water activity and ratio of both population

A Decision Support Tool based on microbial safety prediction for a better dimensioning of modified atmosphere packaging

Predicting microbial safety of fresh products in Modified Atmosphere Packaging (MAP) systems implies to take into account the dynamic of O2 and CO2 exchanges in the system and its effect on microbial growth. In this purpose we coupled mathematical models of gas transfer (permeation through packaging and solubilisation / diffusion within food) with predictive microbiology models that take into account the effect of CO2 and O2 partial pressure in headspace and corresponding dissolved concentrations in the food. This mechanistic model was validated in simplified and in real conditions using dedicated challenge-tests performed on poultry meat, fresh salmon and processed cheese, inoculated with either Listeria monocytogenes or Pseudomonas fluorescens.Once validated, this model could be used as a Decision Support Tool in order to optimize the initial packaging atmosphere (level of O2 and CO2) and / or the geometry (ratio headspace volume to food mass). This tool could also be used to identify the packaging gas permeability the most suitable for maintaining the targeted % of gas initially flushed in the pack within a given tolerance. This approach permits a better dimensioning of MAP of fresh produce by selecting the packaging material fitted to “just necessary” (and not by default the most barrier one). The connexion of this model with dedicated databases gathering gas permeabilities of commonly used packaging materials allows us to obtain as output a ranking of the most suitable materials. This tool would be very useful for all stakeholders of the fresh produce chain. A demonstration of this Decision Support Tool is here proposed with the pipeline between mathematical models and related databases

Fracture toughness of glasses and hydroxyapatite: a comparative study of 7 methods by using Vickers indenter

Numerous methods have been proposed to estimate the indentation fracture toughness Kic for brittle materials. These methods generally uses formulæ established from empirical correlations between critical applied force, or average crack length, and classical fracture mechanics tests. This study compares several models of fracture toughness calculation obtained by using Vickers indenters. Two optical glasses (Crown and Flint), one vitroceramic (Zerodur) and one ceramic (hydroxyapatite) are tested. Fracture toughness and hardness are obtained by using instrumented Vickers indentation at micrometer scale. Young's moduli are obtained by instrumented Berkovich indentation at nanometer scale. Fracture toughness is calculated with models involving crack length measurements, and by models free of crack length measurements by considering critical force, chipping, pop-in. Finally, method based on the cracking energy, commonly employed for coated materials is also used. The aim of this work is to compare seven methods, which enable the facture toughness determination, on four brittle materials. To do so, it was necessary to determine some specific constant in the case of Vickers tip use. On the one hand, results show that methods using crack length, critical force, edge chipping or pop-in lead to comparable results, and the advantages and drawbacks are highlighted. On the other hand, the indentation energy method leads to underestimated results of about 20%

Mechanical properties of thermally sprayed porous alumina coating by Vickers and Knoop indentation

Depending on the thermal spraying conditions, coatings obtained can present different defects, like pores, cracks and/or unmelted particles, and different surface roughnesses, that can affect the determination of the hardness and elastic modulus. The present work investigates the mechanical properties, determined by means of Knoop and Vickers indentations, of a plasma as-sprayed alumina coating, obtained with a nano-agglomerated powder sprayed using a PTF4 torch, in order to highlight how the surface defects interfere into the indentation process. As a main result, Knoop indentation compared to Vickers one gives less dispersive results (15% and 33%, respectively), that are, in addition, more representative of the coating properties. The mean values obtained are 110 ± 40 GPa for the elastic modulus and 1.75 ± 0.42 GPa for the hardness. In addition, and for the two indenter types used, multicyclic indentation has been performed because it allows a more appropriate characterization of such heterogeneous coatings due to the representation of the mechanical properties as a function of the indentation load and/or the penetration depth, leading to more reliable results according to the depth-variability of the coating microstructure