Spatially modulated magnetic structure of EuS due to the tetragonal domain structure of SrTiO3_3

The combination of ferromagnets with topological superconductors or insulators allows for new phases of matter that support excitations such as chiral edge modes and Majorana fermions. EuS, a wide-band-gap ferromagnetic insulator with a Curie temperature around 16 K, and SrTiO$_3$ (STO), an important substrate for engineering heterostructures, may support these phases. We present scanning superconducting quantum interference device (SQUID) measurements of EuS grown epitaxially on STO that reveal micron-scale variations in ferromagnetism and paramagnetism. These variations are oriented along the STO crystal axes and only change their configuration upon thermal cycling above the STO cubic-to-tetragonal structural transition temperature at 105 K, indicating that the observed magnetic features are due to coupling between EuS and the STO tetragonal structure. We speculate that the STO tetragonal distortions may strain the EuS, altering the magnetic anisotropy on a micron-scale. This result demonstrates that local variation in the induced magnetic order from EuS grown on STO needs to be considered when engineering new phases of matter that require spatially homogeneous exchange

Optimisation des paramètres de formulation des bétons destinés à la préfabrication des blocs de béton par une approche RNA (Réseaux de Neurones Artificiels)

Le présent travail a pour objectif l'optimisation du dosage de ciment, de la durée de vibration et du dosage de l'eau dans la formulation des bétons fermes, destinés à la préfabrication des blocs de construction. Ce type de béton n'a pas de méthode de formulation propre, comme dans le cas des bétons classiques. Pour ce, nous avons réalisés 100 compositions, en faisant varier le dosage d'eau (4, 6, 8, 10 et 12%) et celui du ciment (5, 7.5, 10, 12.5 et 15%), tout en appliquant différentes durées de vibration (15, 30, 60, 120s). La réponse qui a été mesurée dans notre cas et prise comme critère de formulation est la densité sèche. Une approche dite « Réseaux de Neurones Artificiels (RNA) » a été utilisée afin d‟apprécier l'effet de chaque paramètre sur la densité sèche. Les résultats obtenus montrent l'efficacité de cette approche pour l'optimisation des paramètres de formulations. Des dosages optimaux en ciment et en eau, pour lesquels la densité sèche est maximale, ont été trouvés

Rose geranium essential oil as a source of new and safe anti-inflammatory drugs

Background: Since the available anti-inflammatory drugs exert an extensive variety of side effects, the search for new anti-inflammatory agents has been a priority of pharmaceutical industries.Aims: The aim of the present study was to assess the anti-inflammatory activities of the essential oil of rose geranium (RGEO).Methods: The chemical composition of the RGEO was investigated by gas chromatography. The major components were citronellol (29.13%), geraniol (12.62%), and citronellyl formate (8.06%). In the carrageenaninduced paw edema, five different groups were established and RGEO was administered orally in three different doses.Results: RGEO (100 mg/kg) was able to significantly reduce the paw edema with a comparable effect to that observed with diclofenac, the positive control. In addition, RGEO showed a potent anti-inflammatory activity by topical treatment in the method of croton oil-induced ear edema. When the dose was 5 or 10 ml of RGEO per ear, the inflammation was reduced by 73 and 88%, respectively. This is the first report to demonstrate a significant anti-inflammatory activity of Algerian RGEO. In addition, histological analysis confirmed that RGEO inhibited the inflammatory responses in the skin.Conclusion: Our results indicate that RGEO may have significant potential for the development of novel antiinflammatory drugs with improved safety profile.Keywords: essential oils; rose geranium; citronellol; anti-inflammatory effect; skin inflammation; histopathology; carrageenan; croto

Lemon grass (Cymbopogon citratus) essential oil as a potent anti-inflammatory and antifungal drugs

Background: Volatile oils obtained from lemon grass [Cymbopogon citratus (DC.) Stapf, Poaceae family] are used in traditional medicine as remedies for the treatment of various diseases.Aims: In the present study, lemon grass essential oil (LGEO) was evaluated for its in vivo topical and oral  antiinflammatory effects, and for its in vitro antifungal activity using both liquid and vapor phases.Methods:The chemical profile ofLGEOas determined bygas chromatography-mass spectrometry analysis revealed twomajor components: geranial (42.2%), and neral (31.5%). The antifungal activity of LGEOwas evaluated against several pathogenic yeasts and filamentous fungi using disc diffusion and vapor diffusion methods.Results: LGEO exhibited promising antifungal effect against Candida albicans, C. tropicalis, and Aspergillus niger, with different inhibition zone diameters (IZDs) (35-90 mm). IZD increased with increasing oil volume. Significantly, higher anti-Candida activity was observed in the vapor phase. For the evaluation of the antiinflammatory effect, LGEO (10 mg/kg, administered orally) significantly reduced carrageenan-induced paw edema with a similar effect to that observed for oral diclofenac (50 mg/kg), which was used as the positive control. Oral administration of LGEO showed dose-dependent anti-inflammatory activity. In addition, topical application of LGEO in vivo resulted in a potent anti-inflammatory effect, as demonstrated by using the mouse model of croton oil-induced ear edema. To our knowledge, this is the first such report to be published. The topical application of LGEO at doses of 5 and 10 mL/ear significantly reduced acute ear edema induced by croton oil in 62.5 and 75% of the mice, respectively. In addition, histological analysis clearly confirmed that LGEO inhibits the skin inflammatory response in animal models.Conclusion: Results of the present study indicate that LGEO has a noteworthy potential for the development of drugs for the treatment of fungal infections and skin inflammation that should be explored in future studies.Keywords: lemon grass; essential oil; antifungal activity; anti-inflammatory effect; citral; aromatherap

Paediatric Behcet's Disease: A Comprehensive Review with an Emphasis on Monogenic Mimics

Behçet’s disease (BD) is a polygenic condition with a complex immunopathogenetic background and challenging diagnostic and therapeutic concepts. Advances in genomic medicine have provided intriguing insights into disease pathogenesis over the last decade, especially into monogenic mimics of BD. Although a rare condition, paediatric BD should be considered an important differential diagnosis, especially in cases with similar phenotypes. Emerging reports of monogenic mimics have indicated the importance of genetic testing, particularly for those with early-onset, atypical features and familial aggregation. Treatment options ought to be evaluated in a multidisciplinary setting, given the complexity and diverse organ involvement. Owing to the rarity of the condition, there is a paucity of paediatric trials; thus, international collaboration is warranted to provide consensus recommendations for the management of children and young people. Herein, we summarise the current knowledge of the clinical presentation, immunopathogenetic associations and disease mechanisms in patients with paediatric BD and BD-related phenotypes, with particular emphasis on recently identified monogenic mimics

FRESH CONCRETE PROPERTIES AND COMPRESSIVE STRENGTH OF SELF COMPACTING CONCRETES WITH SILICA FUME AND FLY ASH

Kendiliğinden yerleşen betonlar (KYB), geleneksel betona oranla işlenebilirlik, işçilik maliyetindeki azalmalar ve yüksek dayanım gibi önemli faydalar sağlayan beton teknolojisindeki gelişmelerdendir. KYB üretiminde yüksek oranda su azaltıcı süperakışkanlaştırıcı kimyasal katkılar, fazla miktarda toz malzeme ve/veya viskozite düzenleyici katkı maddesi kullanılmalıdır. Kendiliğinden yerleşme yeteneği; doldurma yeteneği, ayrışmaya karşı direnç ve geçiş yeteneği olmak üzere 3 parametre ile karakterize edilebilir. KYB üretiminde toz malzeme olarak genellikle kireçtaşı tozu, uçucu kül, granüle yüksek fırın cürufu ve silis dumanı kullanılmaktadır. Bu çalışmada mineral katkı maddesi olarak çimento yerine ağırlıkça % 5, % 10 ve % 15 oranlarında silis dumanı ve % 25, % 40 ve % 55 oranlarında uçucu kül kullanılarak KYB üretilmiş ve taze beton özellikleri ile sertleşmiş betonların 3, 7 ve 28 günlük basınç dayanımları belirlenmiştir. silis dumanı ilavesi basınç dayanımlarında artışa yol açarken uçucu kül katkılı betonlarda dayanım azalmaları tespit edilmiştir. En yüksek basınç dayanımı değeri 88 MPa değeri ile %15 silis dumanı kullanılarak üretilen betonlardan elde edilmiştir.Self Compacting Concrete, is one of the developments in concrete technology, which have important benefitsas workability, labor cost reductions and high-strength, compared to traditional concrete. In SCC production, high-range water reducing super plasticizer chemical additives, powder material and/or viscosity regulators additive must be used. Self-settlement capability may be characterized with 3 parameters; filling ability, resistance to decomposition and, passing ability between reinforcement bars. Limestone powder, fly ash, granulated blast furnace slag and silica fume is used as a powder material in SCC production. In this study SCC were produced with using silica fume instead of cement by weight, by the ratios of 5%, 10% and 15%, and fly ash with the ratios of 25%, 40% and 55%. Fresh concrete properties and 3, 7 and 28 days compressive strengths were determined. While SF increased compressive strength, addition of fly ash, on the contrary, decreased it. The highest compressive strength was observed from the concrete specimens with using 15% silica fume, with the value of 88 MPa.&nbsp

Linear magnetoresistance in topological insulators: Quantum phase coherence effects at high temperatures

In addition to the weak antilocalization cusp observed in the magnetoresistance (MR) of topological insulators at low temperatures and low magnetic fields, we find that the high-field MR in Bi2Te2Se is linear in field. At fields up to B=14T the slope of this linear-like MR is nearly independent of temperature over the range T=7 to 150K. We find that the linear MR arises from the competition between a logarithmic phase coherence component and a quadratic component. The quantum phase coherence dominates up to high temperatures, where the coherence length remains longer than the mean free path of electrons

Modified electrical transport probe design for standard magnetometer

Making electrical transport measurements on a material is often a time consuming process that involves testing a large number of samples. It is thus inconvenient to wire up and rewire samples on to a sample probe. We therefore present a method of modifying Quantum Design's MPMS SQUID magnetometer transport probe that simplifies the process of sample mounting. One of the difficulties to overcome is the small diameter of the sample space. A small socket is designed and mounted on the probe so that various samples mounted on individual headers can be readily exchanged in the socket. We also present some test results on the topological insulator Bi2Te2Se using the modified probe

Inducing magnetism onto the surface of a topological crystalline insulator

Inducing magnetism onto a topological crystalline insulator (TCI) has been predicted to result in several novel quantum electromagnetic effects. This is a consequence of the highly strain-sensitive band topology of such symmetry-protected systems. We thus show that placing the TCI surface of SnTe in proximity to EuS, a ferromagnetic insulator, induces magnetism at the interface between SnTe and EuS and thus breaks time-reversal-symmetry in the TCI. Magnetotransport experiments on SnTe-EuS-SnTe trilayer devices reveal a hysteretic lowering of the resistance at the TCI surface that coincides with an increase in the density of magnetic domain walls. This additional conduction could be a signature of topologically-protected surface states within domain walls. Additionally, a hysteretic anomalous Hall effect reveals that the usual in-plane magnetic moment of the EuS layer is canted towards a perpendicular direction at the interface. These results are evidence of induced magnetism at the SnTe-EuS interfaces resulting in broken time-reversal symmetry in the TCI.Comment: Accepted for publication in Physical Review