A finite-step method for estimating the spanwise lift distribution of wings in symmetric, yawed, and rotary flight at low speeds

The finite-step method was programmed for computing the span loading and stability derivatives of trapezoidal shaped wings in symmetric, yawed, and rotary flight. Calculations were made for a series of different wing planforms and the results compared with several available methods for estimating these derivatives in the linear angle of attack range. The agreement shown was generally good except in a few cases. An attempt was made to estimate the nonlinear variation of lift with angle of attack in the high alpha range by introducing the measured airfoil section data into the finite-step method. The numerical procedure was found to be stable only at low angles of attack

Slender body theory programmed for bodies with arbitrary cross section

A computer program developed for determining the subsonic pressure, force, and moment coefficients for a fuselage-type body using slender body theory is described. The program is suitable for determining the angle of attack and sideslipping characteristics of such bodies in the linear range where viscous effects are not predominant. Procedures developed which are capable of treating cross sections with corners or regions of large curvature are outlined

Robust superconductivity and the suppression of charge-density wave in Ca3(Ir1−xRhx)4Sn13\text{Ca}_{3}(\text{Ir}_{1-x}\text{Rh}_{x})_{4}\text{Sn}_{13} single crystals at ambient pressure

Single crystals of Ca$_3$(Ir$_{1-x}$Rh$_x$)$_4$Sn$_{13}$ (3-4-13) were synthesized by flux growth and characterized by X-ray diffraction, EDX, magnetization, resistivity and radio frequency magnetic susceptibility tunnel diode resonator (TDR) techniques. Compositional variation of the Rh/Ir ratio was used to study the coexistence and competition between the charge density wave (CDW) and superconductivity. The superconducting transition temperature varies from approximately 7 K in pure Ir ($x=0$) to approximately 8.3 K in pure Rh ($x=1$). Temperature-dependent electrical resistivity reveals monotonic suppression of the CDW transition temperature, $T_{\text{CDW}}(x)$. The CDW starts in pure Ir, $x=0$, with $T_{\text{CDW}}\approx40$~K and extrapolates roughly linearly to zero at $x_c=0.58$ under the dome of superconductivity. Magnetization and transport measurements show a significant influence of CDW on the superconducting and normal state. Vortex pinning is substantially enhanced in the CDW region, and the resistivity is larger in this part of the phase diagram. The London penetration depth is attenuated exponentially upon cooling at low temperatures for all compositions, indicating a fully-gapped Fermi surface. We conclude that a novel $\text{Ca}_3(\text{Ir}_{1-x}\text{Rh}_x)_4\text{Sn}_{13}$ alloy with coexisting/competing CDW and superconductivity, is a good candidate to look for a composition-driven quantum critical point at ambient pressure

Itinerant G-type antiferromagnet SrCr2As2 studied by magnetization, heat capacity, electrical resistivity, and NMR measurements

The physical properties of itinerant antiferromagnetic (AFM) SrCr$_2$As$_2$ with body-centered tetragonal ThCr$_2$Si$_2$ structure were investigated in single crystalline and polycrystalline forms by electrical resistivity $\rho$, heat capacity $C_{\rm p}$, magnetic susceptibility $\chi$ versus temperature~$T$ and magnetization $M$ versus applied magnetic field $H$ isotherm measurements as well as $^{75}$As and $^{53}$Cr nuclear magnetic resonance (NMR) measurements in the wide temperature range $T$ = 1.6--900 K. From the $\chi(T)$ and $^{75}$As NMR measurements, the G-type AFM state below $T_{\rm N}$ = 615(15) K has been determined, consistent with the previous neutron-diffraction measurements. Direct evidence of magnetic ordering of the Cr spins was shown by the observation of the $^{53}$Cr NMR spectrum under $H$ = 0. From the $\chi(T)$ measurements on single-crystal SrCr$_2$As$_2$ under the two different magnetic field directions $H||ab$ and $H||c$ in the AFM state, the Cr ordered moments are shown to align along the $c$ axis in the G-type AFM state. The metallic state is directly evidenced by the $\rho$, $C_{\rm p}$, and NMR measurements, and the density of states at the Fermi energy ${\cal D}(E_{\rm F})$ in the AFM state is estimated to be 7.53 states/eV f.u. for both spin directions which is almost twice the bare ${\cal D}(E_{\rm F})$ estimated from first-principles calculations, suggesting an enhancement of the conduction-carrier mass by a factor of two in the AFM state. The ${\cal D}(E_{\rm F})$ is found to be nearly constant below at least 100 K and is independent of $H$. The $\rho(T)$ is found to show $T$-linear behavior above $T_{\rm N}$ and exhibits positive curvature below $T_{\rm N}$ where significant loss of spin-disorder scattering upon magnetic ordering is observed.Comment: 14 pages, 12 figures, accepted for publication in Phys. Rev.

Implants in the severely resorbed mandibles: whether or not to augment? What is the clinician’s preference?

Contains fulltext : 96000.pdf (publisher's version ) (Open Access)INTRODUCTION: The aim of this study is to inventory in the Netherlands which therapy is the clinician's first choice when restoring the edentulous mandible. MATERIAL AND METHODS: A questionnaire was sent to all Dutch Oral and Maxillofacial surgeons. As part of this, the surgeons were invited to treat five virtual edentulous patients, differing only in mandibular residual height. RESULTS: In cases of a sufficient residual height of 15 mm, all surgeons were in favour to insert solely two implants to anchor an overdenture. In case of a residual height of 12 mm, 10% of the surgeons choose for an augmentation procedure. If a patient was presented with a mandibular height of 10 mm, already 40% of the OMF surgeons executed an augmentation procedure. Most (80%) surgeons prefer the (anterior) iliac crest as donor site. The choice of 'whether or not to augment' was not influenced by the surgeon's age; however, the hospital, where he was trained, did. Surgeons trained in Groningen were more in favour of installing short implants in mandibles with reduced vertical height. DISCUSSION: As the option overdenture supported on two interforaminal implants is reimbursed by the Dutch health assurance, this treatment modality is very popular in the Netherlands. From a point of costs and to minimize bypass comorbidity, surgeons should be more reluctant in executing augmentation procedures to restore the resorbed edentulous mandible as it is dated in literature that also in mandibles with a residual height of 10 mm or less, solely placing implants, thus without an augmentation procedure in advance, is a reliable treatment option

Antifibrotic Effects of the Dual CCR2/CCR5 Antagonist Cenicriviroc in Animal Models of Liver and Kidney Fibrosis

Background & Aims Interactions between C-C chemokine receptor types 2 (CCR2) and 5 (CCR5) and their ligands, including CCL2 and CCL5, mediate fibrogenesis by promoting monocyte/macrophage recruitment and tissue infiltration, as well as hepatic stellate cell activation. Cenicriviroc (CVC) is an oral, dual CCR2/CCR5 antagonist with nanomolar potency against both receptors. CVC’s anti-inflammatory and antifibrotic effects were evaluated in a range of preclinical models of inflammation and fibrosis. Methods Monocyte/macrophage recruitment was assessed in vivo in a mouse model of thioglycollate-induced peritonitis. CCL2-induced chemotaxis was evaluated ex vivo on mouse monocytes. CVC’s antifibrotic effects were evaluated in a thioacetamide-induced rat model of liver fibrosis and mouse models of diet-induced non-alcoholic steatohepatitis (NASH) and renal fibrosis. Study assessments included body and liver/kidney weight, liver function test, liver/kidney morphology and collagen deposition, fibrogenic gene and protein expression, and pharmacokinetic analyses. Results CVC significantly reduced monocyte/macrophage recruitment in vivo at doses ≥20 mg/kg/day (p < 0.05). At these doses, CVC showed antifibrotic effects, with significant reductions in collagen deposition (p < 0.05), and collagen type 1 protein and mRNA expression across the three animal models of fibrosis. In the NASH model, CVC significantly reduced the non-alcoholic fatty liver disease activity score (p < 0.05 vs. controls). CVC treatment had no notable effect on body or liver/kidney weight. Conclusions CVC displayed potent anti-inflammatory and antifibrotic activity in a range of animal fibrosis models, supporting human testing for fibrotic diseases. Further experimental studies are needed to clarify the underlying mechanisms of CVC’s antifibrotic effects. A Phase 2b study in adults with NASH and liver fibrosis is fully enrolled (CENTAUR Study 652-2-203; NCT02217475)

Barrier Tissue Macrophages: Functional Adaptation to Environmental Challenges

Macrophages are found throughout the body, where they have crucial roles in tissue development, homeostasis and remodeling, as well as being sentinels of the innate immune system that can contribute to protective immunity and inflammation. Barrier tissues, such as the intestine, lung, skin and liver, are exposed constantly to the outside world, which places special demands on resident cell populations such as macrophages. Here we review the mounting evidence that although macrophages in different barrier tissues may be derived from distinct progenitors, their highly specific properties are shaped by the local environment, which allows them to adapt precisely to the needs of their anatomical niche. We discuss the properties of macrophages in steady-state barrier tissues, outline the factors that shape their differentiation and behavior and describe how macrophages change during protective immunity and inflammation

CMC Materials for Lightweight and Low CTE Applications

Carbon fibre reinforced CMC materials, originally developed for the thermal protection of reusable spacecrafts, offer a great applicability for extreme lightweight and thin walled structures combining an excellent strength to density ratio with a close to zero thermal expansion behaviour. These outstanding properties and a cost efficient manufacturing route, predestine these C/C-SiC materials for a variety of low CTE applications e.g. for telescopes or calibration artefacts. This paper deals with principal correlations between the thermal expansion of different C/C-SiC materials as well as their microstructural characterisation. Additionally, two special applications designed, manufactured and tested successfully in collaboration with industrial partners will be described exemplarily. One is a telescope structure for the data link between satellites based on an optical concept. The other application is a new calibration ball plate for coordinate measuring machines