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Natural dihydrogen (H2) exploration is now active in various countries, but tools and workflows that help to characterize prospective zones are still poorly defined. This review paper is dedicated to share our experience in characterizing H2 plays based on exploration efforts carried out in many countries in Europe, North and South America, Africa, and Oceania between 2017 and 2023. We decided to focus on onshore exploration where three main reactions are generating H2: (i) redox reactions between Fe2+ and H2O, (ii) radiolysis of water and, (iii) organic late maturation where H2 comes from hydrocarbons. This leads to classify the H2 generating rocks (H2_GR) into four types that seem us the more likely to be of economic interest: basic and ultrabasic rocks of oceanic/mantellic affinity (H2_GR1), iron-rich bearing sedimentary and intrusive rocks, (H2_GR2), radioactive continental rocks (H2_GR3) and organic matter-rich rocks (H2_GR4). For the pre-fieldwork, the workflow aims to target new promising areas for H2 exploration. Cross-referencing the presence of H2_GR in the basement, classical geological-hydrodynamic features (fault, water source), and already-known H2 occurrences at the surface remain essential but should be accompanied by remote sensing analyses to detect possible H2 occurrences. For the fieldwork, the focus is made on gas and rocks. A discussion is led concerning the importance of punctual measurements and long-term monitoring of gas seepages, that allow to conclude on dynamics of H2 leakage from depth through space and time. For the post-fieldwork, we present the most useful analytical tools to characterize H2 gas seepages and the suspected H2_GR. The critical parameters to estimate the H2 potential of a rock are the content in Fe2+/Fetot (H2_GR1 and H2_GR2), the content of radioactive elements U, Th, K (H2_GR3), and the total organic content (H2_GR4). The hydrogen exploration is in its infancy and all the profession is attempting to define an automated and fast workflow. We are still far away from it due to a lack of data, yet this review presents a practical guide based on the current knowledge.

The Asal–Ghoubbet active rift in the Republic of Djibouti is a site of interest for geothermal energy and natural hydrogen, and previous studies have indicated that dihydrogen (H2) emanates from this rift. However, the well-known serpentinization reaction does not appear to be the main mechanism generating H2 at this site. Rather, the H2 is generated as follows: (1) by alteration of basaltic lava at depth via reaction with seawater flowing from Ghoubbet Bay towards Lake Asal; (2) by simple degassing of the volcanic chamber located a few kilometers below the Fiale Caldera in the rift axis; or (3) as a result of pyritization processes via the oxidation of H2S. Study of microorganisms did not indicate any production or consumption of H2, CO2, or CH4; therefore, it is unlikely that microorganisms affected H2 gas contents measured at the surface. However, air contamination at fumaroles is typically considerable and may limit interpretation of such processes. Drill cuttings from the Fiale 1 (F1) and Gale le Goma 1 (Glc1) wells (located on the inner and outer rift margins, respectively) were analyzed to determine where H2 is generated. Total rock analyses indicated distinct zones at depths of 464 m and 280 m for F1 and Glc1, respectively, representing the boundary between the Asal and Stratoïd Basalts. 57Fe Mössbauer analyses show a decrease in the percentage of Fe3+ at depth, indicating that Fe2+-rich minerals, particularly in the Stratoïd Basalts, may be a source of H2. Based on well data from the rift center and the outer rift margin, it is evident that H2 is present at the surface in the rift axis and that this area offers good remnant potential because of the presence of Fe-rich chlorite. Conversely, few H2 emissions were measured at the surface on the outer rift margins, although well data showed some H2 (∼0.25%) at depth. The presence of a cap rock in the rift axis has not yet been proven; however, the high loss on ignition and the mineralogy in well Glc1 may indicate that the rocks are sufficiently altered into clays to offer potential as a H2 seal. If so, the rift margins would offer greater exploration potential than the rift center.

Background: Dentinogenesis imperfecta is a genetic disorder of the dentin occurring during the tooth development. It leads to many structural changes that can be identified clinically (brownish colored teeth, cracked enamel) and radiologically (globular crown, cervical constriction, short roots, and obliterated pulp chamber and/or root canals). The aim of this study was to determine by panoramic radiographs assessment the incidence of dentinogenesis imperfecta in a group of patients attending a specialized maxillofacial imaging center in Paris, France., Material and Methods: A retrospective observational study was conducted using panoramic radiographs of 8830 patients (3723 males and 5107 females), which were used to search the radiological criteria of dentinogenesis imperfecta., Results: In our sample, the prevalence of dentinogenesis imperfecta was 0.057%. Out of the 8830 subjects, 0.080% of the males presented the radiological signs of the dentinogenesis imperfecta against 0.039% of the females., Conclusion: In our study, we found that dentinogenesis imperfecta is a relatively rare dental anomaly in France, with a rate different from the rates reported in other studies and with no disparity in prevalence among genders., Competing Interests: There are no conflicts of interest.

Background: Bone preservation is an essential issue in the context of last teeth extraction and complete edentulism. The intended treatment, whether a complete denture or an implant placement, is facilitated with a voluminous residual ridge. Bone resorption after multiple extractions has not been as well studied as the bone resorption that occurs after the extraction of a single tooth. Recent advances in bone substitute materials have revived this issue. The purpose of this study is to evaluate the interest in using bone substitute material to fill the socket after last teeth extraction in a maxillary immediate complete denture procedure compared with the conventional protocol without socket filling., Methods/design: A randomized, controlled, clinical trial was designed. The 34 participants eligible for maxillary immediate complete denture were divided into two groups. Complete dentures were prepared despite persistence of the last anterior teeth. The control group received a conventional treatment including denture placement immediately after extractions. In the experimental group, in addition to the immediate denture placement, a xenograft bone-substitute material (Bio-Oss Collagen®) was placed in the fresh sockets. The primary outcome of the study is to compare mean bone ridge height loss 1 year after maxillary immediate complete denture placement, with or without bone-substitute material, in incisor and canine sockets. The secondary outcomes are to compare the average bone ridge height and width loss for each extraction site. An original quantitative evaluation method using cone beam computed tomography was designed for reproducible measurements, with a radio-opaque denture duplicate. Two independent operators perform the radiologic measurements., Discussion: The immediate complete denture technique limits bone resorption in multiple extraction situations and thus allows better denture retention and better options for implant placement. To compare the benefit of using any bone socket-filling material, we proposed a quantitative evaluation protocol of resorption in the specific case of the last anterior maxillary teeth extraction with immediate denture placement., Trial Registration: ClinicalTrials.gov, NCT02120053 . Registered on 18 April 2014.

Starting from potent inhibitors of PI3Kα having poor general kinase selectivity (e.g., 1 and 2), optimisation of this series led to the identification of 25, a potent inhibitor of PI3Kα (wild type, E545K and H1047R mutations) and PI3Kδ, selective versus PI3Kβ and PI3Kγ, with excellent general kinase selectivity. Compound 25 displayed low metabolic turnover and suitable physical properties for oral administration. In vivo, compound 25 showed pharmacodynamic modulation of AKT phosphorylation and near complete inhibition of tumour growth (93% tumour growth inhibition) in a murine H1047R PI3Kα mutated SKOV-3 xenograft tumour model after chronic oral administration at 25mg/kg b.i.d. Compound 25, also known as AZD8835, is currently in phase I clinical trials., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The authors, both working as radiologist in private practice, have initiated the Cone Beam technique as soon as 1999 and report their own experience. Cone Beam Computerized Tomography (CBCT) is dedicated to hard tissues imaging thus specifically adapted to oral implantology and maxillofacial surgery. It has the advantage to deliver low dose radiation, compared to other techniques. CBCT permits anatomical volume acquisition. After data analysis on computer, distances and implants 3D simulation can be checked. CBCT differs from CT scan because it is more adapted to hard tissues, it has a better resolution than CT, and because it delivers lower doses. Its isotropic pixel particularity which gives exact linear measurements, and the fact that metallic artifacts are significatively diminished, gives CBCT its high interest in implantology. These advantages of CBCT and the small place needed for its installation explain its global wide spreading. CBCT is now considered to be the gold standard in dental and maxillofacial sectional imaging. Because of its biomeasuring capacity, its bi- and tridimensional reconstruction possibilities, its surgical navigation and simulation capacity, it is now widely used in implantology., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

A new series of quinoline ether inhibitors, which potently and selectively inhibit PDGFR tyrosine kinases, is described in this Letter. Compounds 23 and 33 are selective, low nanomolar inhibitors of PDGFRα and β, display good pharmacokinetics in rat and dog and are active in vivo at low doses when given orally twice daily. Further evaluation of these compounds is warranted., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A new series of Quinazoline Ether Inhibitor which potently inhibits VEGFR-2 and PDGFR tyrosine kinases is described here. In vitro, pharmacokinetics and in vivo evaluations led to the selection of AZD2932., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Every imaging test is justified by clinical facts and optimized to reduce the X-rays dose delivered to patients. If results from orthopantomogram are inadequate, a cross-sectional tomographic technique is indicated. Today, cone beam computed tomography yields images comparable to CT scan or even better. Some dedicated cone beam machines allow the study of small volumes with a very high definition. Dental and maxillofacial imaging as a whole, including endodontic imaging, formerly dreaded by imagers, is now accessible to cross-sectional imaging.

A new class of 1-acetanilide-4-aminopyrazole-substituted quinazoline Aurora kinase inhibitors has been discovered possessing highly potent cellular activity. Continuous infusion into athymic mice bearing SW620 tumors of the soluble phosphate derivative 2 led to dose-proportional exposure of the des-phosphate compound 8 with a high-unbound fraction. The combination of potent cell activity and high free-drug exposure led to pharmacodynamic changes in the tumor at low doses, indicative of Aurora B-kinase inhibition and a reduction in tumor volume.

From the first dental image in 1895 and the first image of the head in 1896 by Otto Walkhoff to 3D modern cephalic assessment there has been a continuous evolution in imaging techniques. Digital cephalic volume data processing allows 2D and 3D reformations in accordance with morphologic, topographic and biodimensional anatomic needs. In France, Jacques Treil demonstrated its application in cephalometry through his CT scan research. The transcription of European Directives to national laws leads to rigorous radioprotection measures. The worldwide spread of cone beam technique devoted specifically to dentomaxillofacial imaging should now reduce the reluctance of orthodontists to provide radiological examinations to children by significantly reducing radiation exposure. This is certainly the technique of the future.

The Aurora kinases have been the subject of considerable interest as targets for the development of new anticancer agents. While evidence suggests inhibition of Aurora B kinase gives rise to the more pronounced antiproliferative phenotype, the most clinically advanced agents reported to date typically inhibit both Aurora A and B. We have discovered a series of pyrazoloquinazolines, some of which show greater than 1000-fold selectivity for Aurora B over Aurora A kinase activity, in recombinant enzyme assays. These compounds have been designed for parenteral administration and achieve high levels of solubility by virtue of their ability to be delivered as readily activated phosphate derivatives. The prodrugs are comprehensively converted to the des-phosphate form in vivo, and the active species have advantageous pharmacokinetic properties and safety pharmacology profiles. The compounds display striking in vivo activity, and compound 5 (AZD1152) has been selected for clinical evaluation and is currently in phase 1 clinical trials.

In this work, we report on the realization of an innovating micro system for NMR spectroscopy on small sample volume (30-100 nL). We propose a micro system based on Printed Circuit Board (PCB) technology for the NMR probe associated to a micro fluidic system made with polymer (COC). The comparison of several samples during the same NMR experiments could provide more precise information. In that context, we have realized a micro-fluidic system with two cavities, each cavity presenting a volume of 37 nl. The fabrication process is described, and first results are reported. The tight sealing of the micro-fluidic system has been demonstrated and preliminary NMR experiment results are presented.

Although NMR has the ability to investigate biological systems non-destructively, its low sensitivity primarily has hampered their investigation compared to other analytical techniques. Therefore, optimi zing radio frequency (RF) coils to improve sensitivity do offer benefits in MR spectroscopy (MRS). Sensitivity may be improved for mass- and volume-limited samples if the size of the detection RF coils matches the sample size. In this paper, the mass- and concentration-limit of detection (LOD(m), LOD(c)) for an implantable microcoil will be estimated by MRS measurements and then compared with their analytical values. For a sample containing a solution of several cerebral metabolites, for the Choline case, the LODm is 5.7 . 10(-9)mol and LODc of 3.8 mM. These preliminary results enable to open largely the biomedical applications based on cerebral metabolism investigation on small animal experiments.

The synthesis of a novel series of quinazolines substituted at C4 by five-membered ring aminoheterocycles is reported. Their in vitro structure-activity relationships versus Aurora A and B serine-threonine kinases is discussed. Our results demonstrate that quinazolines with a substituted aminothiazole at C4 possess potent Aurora A and B inhibitory activity and excellent selectivity against a panel of various serine-threonine and tyrosine kinases, as exemplified by compound 46. We found also that the position and nature of the substituent on the thiazole play key roles in cellular potency. Compounds with an acetanilide substituent at C5' have the greatest cellular activity. The importance of the C5' position for substitution has been rationalized by ab initio molecular orbital calculations. Results show that the planar conformation with the sulfur of the thiazole next to the quinazoline N-3 is strongly favored over the other possible planar conformation. Compound 46 is a potent suppressor of the expression of phospho-histone H3 in tumor cells in vitro as well as in vivo, where 46, administered as its phosphate prodrug 54, suppresses the expression of phospho-histone H3 in subcutaneously implanted tumors in nude mice.