Open problems in nuclear density functional theory

This note describes five subjects of some interest for the density functional theory in nuclear physics. These are, respectively, i) the need for concave functionals, ii) the nature of the Kohn-Sham potential for the radial density theory, iii) a proper implementation of a density functional for an "intrinsic" rotational density, iv) the possible existence of a potential driving the square root of the density, and v) the existence of many models where a density functional can be explicitly constructed.Comment: 10 page

Strontium isotope geochemistry of alluvial groundwater: a tracer for groundwater resources characterisation

International audienceThis study presents strontium isotope and major ion data of shallow groundwater and river water from the Ile du Chambon catchment, located on the Allier river in the Massif Central (France). There are large variations in the major-element contents in the surface- and groundwater. Plotting of Na vs. Cl contents and Ca, Mg, NO3, K, SO4, HCO3, Sr concentrations reflect water–rock interaction (carbonate dissolution for Ca, Mg, HCO3 and Sr because the bedrock contains marly limestones), agricultural input (farming and fertilising) and sewage effluents (for NO3, K, SO4), although some water samples are unpolluted. Sr contents and isotope ratios (87Sr/86Sr vary from 0.70892 to 0.71180 along the hydrological cycle) in the groundwater agree with previous work on groundwater in alluvial aquifers in the Loire catchment. The data plot along three directions in a 87Sr/86Sr v. 1/Sr diagram as a result of mixing, involving at least three geochemical signatures–Allier river water, and two distinct signatures that might be related to different water-rock interactions in the catchment. Mixing proportions are calculated and discussed. The alluvial aquifer of the Ile du Chambon catchment is considered, within the Sr isotope systematic, in a larger scheme that includes several alluvial aquifers of the Loire Allier catchment. Keywords: : Loire river, major and trace elements, Sr isotopic ratio, alluvial aquifer, hydrolog

Bypassing Android isolation with fuel gauges: new risks with advanced power ICs

Efficient power management is critical for embedded devices, both for extending their lifetime and ensuring safety. However, this can be a challenging task due to the unpredictability of the batteries commonly used in such devices. To address this issue, dedicated Integrated Circuits known as fuel gauges are often employed outside of the System-On-Chip. These devices provide various metrics about the available energy source and are highly accurate. However, their precision can also be exploited by malicious actors to compromise platform confidentiality if the Operating System fails to intervene. Depending on the fuel gauge and OS configuration, several attack scenarios are possible. In this article, we focus on Android and demonstrate how it is possible to bypass application isolation to recover PINs entered in other processes

Biomarker Identification for Breast Cancer Types Using Feature Selection and Explainable AI Methods

This paper investigates the impact the LASSO, mRMR, SHAP, and Reinforcement Feature Selection techniques on random forest models for the breast cancer subtypes markers ER, HER2, PR, and TN as well as identifying a small subset of biomarkers that could potentially cause the disease and explain them using explainable AI techniques. This is important because in areas such as healthcare understanding why the model makes a specific decision is important it is a diagnostic of an individual which requires reliable AI. Another contribution is using feature selection methods to identify a small subset of biomarkers capable of predicting if a specific RNA sequence will have one of the cancer labels positive. The study begins by obtaining baseline accuracy metric using a random forest model on The Cancer Genome Atlas\u27s breast cancer database to then explore the effects of feature selection, selecting different numbers of features, significantly influencing model accuracy, and selecting a small number of potential biomarkers that may produce a specific type of breast cancer. Once the biomarkers were selected, the explainable AI techniques SHAP and LIME were applied to the models and provided insight into influential biomarkers and their impact on predictions. The main results are that there are some shared biomarkers between some of the subsets that had high influence over the model prediction, LASSO and Reinforcement Feature selection sets scoring the highest accuracy of all sets and obtaining some insight into how the models used the features by using existing explainable AI methods SHAP and LIME to understand how these selected features are affecting the model\u27s prediction

Flight hardware and software operations performance review for BAMMsat-on-BEXUS – a BioCubeSat prototype flown on BEXUS30

BAMMsat-on-BEXUS is a student-led project in which a CubeSat-compatible payload was designed, manufactured, and flown on the BEXUS30 stratospheric balloon. The prototype payload – BAMMsat (Biology, Astrobiology, Medicine, and Materials Science on satellite) – is a modular CubeSat-compatible miniaturised laboratory termed a bioCubeSat. The core flight objective was to perform technology demonstration of the bioCubeSat technology, demonstrating capability to perform experiments in space, and to understand system performance and identify future requirements. The mission aimed to validate pre-flight, flight, and post-flight operations, with a focus on biological and autonomous operations and the novel payload hardware. C. elegans samples were flown in the payload. The mission was partially successful, as the BAMMsat systems and autonomous software operated successfully despite challenging conditions and a large volume of payload performance data was collected; however there were issues maintaining the viability of the samples during flight and microfluidic system issues that impeded sample containment and imaging operations. Post-flight analysis has been performed, the root causes of the issues identified, and upgraded novel payload hardware is currently being developed and tested

Identification and assessment of markers of biotin status in healthy adults

Human biotin requirements are unknown and the identification of reliable markers of biotin status is necessary to fill this knowledge gap. Here, we used an outpatient feeding protocol to create states of biotin deficiency, sufficiency and supplementation in sixteen healthy men and women. A total of twenty possible markers of biotin status were assessed, including the abundance of biotinylated carboxylases in lymphocytes, the expression of genes from biotin metabolism and the urinary excretion of biotin and organic acids. Only the abundance of biotinylated 3-methylcrotonyl-CoA carboxylase (holo-MCC) and propionyl-CoA carboxylase (holo-PCC) allowed for distinguishing biotin-deficient and biotin-sufficient individuals. The urinary excretion of biotin reliably identified biotin-supplemented subjects, but did not distinguish between biotin-depleted and biotin-sufficient individuals. The urinary excretion of 3-hydroxyisovaleric acid detected some biotin-deficient subjects, but produced a meaningful number of false-negative results and did not distinguish between biotin-sufficient and biotin-supplemented individuals. None of the other organic acids that were tested were useful markers of biotin status. Likewise, the abundance of mRNA coding for biotin transporters, holocarboxylase synthetase and biotin-dependent carboxylases in lymphocytes were not different among the treatment groups. Generally, datasets were characterised by variations that exceeded those seen in studies in cell cultures. We conclude that holo-MCC and holo-PCC are the most reliable, single markers of biotin status tested in the present study

Pharmacokinetic-pharmacodynamic correlation of imipenem in pediatric burn patients using a bioanalytical liquid chromatographic method

A bioanalytical method was developed and applied to quantify the free imipenem concentrations for pharmacokinetics and PK/PD correlation studies of the dose adjustments required to maintain antimicrobial effectiveness in pediatric burn patients. A reverse-phase Supelcosil LC18 column (250 x 4.6 mm 5 micra), binary mobile phase consisting of 0.01 M, pH 7.0 phosphate buffer and acetonitrile (99:1, v/v), flow rate of 0.8 mL/min, was applied. The method showed good absolute recovery (above 90%), good linearity (0.25-100.0 µg/mL, r;2;=0.999), good sensitivity (LLOQ: 0.25 µg/mL; LLOD: 0.12 µg/mL) and acceptable stability. Inter/intraday precision values were 7.3/5.9%, and mean accuracy was 92.9%. A bioanalytical method was applied to quantify free drug concentrations in children with burns. Six pediatric burn patients (median 7.0 years old, 27.5 kg), normal renal function, and 33% total burn surface area were prospectively investigated; inhalation injuries were present in 4/6 (67%) of the patients. Plasma monitoring and PK assessments were performed using a serial blood sample collection for each set, totaling 10 sets. The PK/PD target attained (40%T>;MIC) for each minimum inhibitory concentration (MIC: 0.5, 1.0, 2.0, 4.0 mg/L) occurred at a percentage higher than 80% of the sets investigated and 100% after dose adjustment. In conclusion, the purification of plasma samples using an ultrafiltration technique followed by quantification of imipenem plasma measurements using the LC method is quite simple, useful, and requires small volumes for blood sampling. In addition, a small amount of plasma (0.25 mL) is needed to guarantee drug effectiveness in pediatric burn patients. There is also a low risk of neurotoxicity, which is important because pharmacokinetics are unpredictable in these critical patients with severe hospital infection. Finally, the PK/PD target was attained for imipenem in the control of sepsis in pediatric patients with burns.;Desenvolveu-se e aplicou-se método bioanalítico para quantificar concentrações de imipenem livre para estudos de farmacocinética (PK) e de correlação PK/PD dos ajustes de dose requeridos para manter a efetividade antimicrobiana em pacientes pediátricos queimados. Utilizou-se coluna Supelcosil LC18 (250 x 4,6 mm 5 micra), fase móvel binária, consistindo de tampão fosfato 0,01M pH 7,0 e acetonitrila (99:1, v/v) e fluxo de 0,8 mL/min. O método mostrou boa recuperação absoluta (acima de 90%), boa linearidade (0,25-100,0 µg/mL, r;2;=0.999), boa sensibilidade (LLOQ: 0,25 µg/mL; LLOD: 0,12 µg/mL) e estabilidade aceitável. Os valores de precisão inter/intradia foram 7,3/5,9% e a exatidão média foi de 92,9%. O método bioanalítico foi aplicado para quantificar concentrações de fármaco livre em crianças com queimaduras, Seis pacientes pediátricos queimados (idade média de 7,0 anos, 27,5 kg), com função renal normal e 33% da superfície total queimada foram investigados prospectivamente. Lesões por inalação estavam presentes em 4/6 (67%) dos pacientes. O monitoramento plasmático e a as avaliações de PK foram efetuadas utilizando coleção de amostras seriais de sangue para cada série, totalizando 10 conjuntos. O alvo PK/PD alcançado (40%T>;MIC) para cada concentração inibitória mínima (MIC: 0,5, 1,0, 2,0, 4,0 mg/L) ocorreu em porcentagem maior do que 80% dos conjuntos investigados e 100% após o ajuste de dose. Em conclusão, a purificação das amostras do plasma usando técnica de ultrafiltração seguida de quantificação das medidas do imipenem no plasma usando método de cromatografia líquida é bastante simples, útil e necessita de pequenos volumes para as amostras de sangue. Além disso, pequena quantidade de plasma (0,25 mL) é necessário para garantir a efetividade do fármaco nos pacientes pediátricos queimados. Há, ainda, baixo risco de neurotoxicidade, o que é importante, visto que as farmacocinéticas são imprevisíveis nesses pacientes críticos, com grave infecção hospitalar. Finalmente, o alvo PK/PD foi alcançado para o imipenem no controle da sepse em pacientes pediátricos com queimaduras.

Effet de la Densité de Mise en Charge sur la Croissance de la Palourde Amiantis umbonella Élevée sur les Sites de Douda et Obock (Djibouti)

La palourde Amiantis umbonella présente dans les zones intertidales sablonneuses/vaseuses en Asie constitue une source de protéines bon marché de ces régions. Malgré ces potentialités économiques, elle demeure peu étudiée à Djibouti où elle est fait l’objet d’une production. Cette étude a pour but d’étudier l’effet de la densité d’élevage sur la croissance de la palourde Amiantis umbonella. Les expériences ont été conduites sur les sites de Douda avec des densités de 50 individu/m2 et de 100 individu/m2 et Obock avec 50 individu/m2. La taille et le poids des spécimens ont été mesurés toutes les deux semaines, pendant 6 mois de mars à aout 2018. La température moyenne était de 36°C.  Les paramètres de croissance des palourdes ont été estimés avec l’équation de Von Bertalanffy. A la densité de 50 individus/m2, les constantes de croissance K étaient de 0,13 cm/mois et 0,15 cm/mois respectivement à Douda et Obock tandis qu’elle était de 0,11cm/mois pour une densité de 100 individus/m2à Douda. Ainsi, il ressort que la taille commerciale (40 mm) a été obtenue plutôt après 8 semaines à Douda à la densité 50 individus/m2 et Obock contre 14 semaines d’élevage à la densité de 100 individus/m2à Douda. Ces résultats révèlent une amélioration de la croissance de la palourde Amiantis umbonella à la  densité de 50 individus/m2 dans les  conditions d’élevage à Douda et Obock.    The clam Amiantis umbonella found in sandy/muddy intertidal zones in Asia constitutes a cheap source of protein in these regions. Despite its economic potential, it remains little studied in Djibouti where it is produced. This study aims to investigate the effect of stocking density on the growth of the clam Amiantis umbonella. The experiments were conducted at the sites of Douda with densities of 50 individuals/m2 and 100 individuals/m2 and Obock with 50 individuals/m2. The size and weight of the specimens were measured every two weeks, during 6 months from March to August 2018. The average temperature was 36°C. Clam growth parameters were estimated with the Von Bertalanffy equation. At a density of 50 individuals/m2, the growth constants K were 0.13 cm/month and 0.15 cm/month respectively in Douda and Obock while it was 0.11cm/month for a density of 100 individuals/m2 in Douda. Thus, it appears that the commercial size (40 mm) was obtained after 8 weeks in Douda at a density of 50 individuals/m2 and Obock against 14 weeks of rearing at a density of 100 individuals/m2 in Douda. These results reveal an improvement of the growth of the clam Amiantis umbonella at the density of 50 individuals/m2 under the rearing conditions in Douda and Obock.&nbsp