Transdisciplinary research knits together knowledge from diverse epistemic communities in addressing social-environmental challenges, such as biodiversity loss, climate crises, food insecurity, and public health. This article reflects on the roles of philosophy of science in transdisciplinary research while focusing on Indigenous and other subjugated forms of knowledge. We offer a critical assessment of demarcationist approaches in philosophy of science and outline a constructive alternative of transdisciplinary philosophy of science. While a focus on demarcation obscures the complex relations between epistemic communities, transdisciplinary philosophy of science provides resources for meeting epistemic and political challenges of collaborative knowledge production.

The development of a millimeter-wave transparent antenna integrated inside a headlamp for automotive radar application is presented. The antenna consists of two radiating elements: the primary and secondary ones. The primary antenna is the one that is fabricated on RF PCB material (e.g., patch, slot, sectoral horn) and connected directly to the transceiver chip, while the secondary antenna is made of optically transparent materials such as glass, but with a optical transparent electrically conductive coating, well known as transparent conductive oxide (TCO). This antenna is realized as a planar offset reflector to collimate and shape the incoming wave from the primary antenna. This reflector is designed based on the Fresnel theory and the reflectarray concept. The division of the primary and secondary antenna enables the placement of the radar module (that contains the primary antenna) at the base of the headlamp, and therefore it is concealed from the surroundings and hidden from the optical path of the light. The secondary antenna is inserted in the space between the headlamp cover and the light unit. The main challenge here is to provide a maximum on transparency in the visible range of the spectrum with a specially designed and laser-based generated microstructure for the resonant reflection of the radar wavelength. An antenna demonstrator has been fabricated, and together with the headlamp cover, the radiation pattern and realized gain are measured. We reported here the measurement results for several reflector designs and concluded that the headlamp cover gives minimal influence on the antenna performance.

In the field of gas-turbine engineering, entropy waves and fluctuations in fuel–air mixing are of significant importance. The impact of either mechanism on thermoacoustic stability of the engine and combustion noise considerably depends on how they are convected in the combustion chamber. In this work, a novel method is employed to analyse their convection. Both effects are modelled using a transport equation of a passive scalar linearized around the mean field. The linearized transport equation is discretized using finite elements. It is shown that turbulent passive scalar transport can be described by an eddy diffusivity in the linear framework. The method is furthermore validated against direct numerical simulation (DNS) of passive scalar transport in a turbulent channel flow. Taking the mean flow from the DNS as input, the method reproduces transport of periodic passive scalar fluctuations with high accuracy at negligible numerical expense. Previous studies investigated destructive interference of the passive scalar due to a non-uniform mean flow profile, a process termed mean flow shear dispersion. The method introduced in this study, however, allows us to additionally quantify the impact of molecular and turbulent diffusion. For the channel flow under investigation, mean flow shear dispersion is the dominant mechanism at low frequencies while, at higher frequencies, turbulent diffusion needs to be accounted for to reproduce the DNS results. Molecular diffusion, however, only has a minor effect on the overall convection in the turbulent channel flow.

During glacial times, the North Atlantic region was affected by serious climate changes corresponding to Dansgaard-Oeschger cycles that were linked to dramatic shifts in sea temperature and moisture transfer to the continents. However, considerable efforts are still needed to understand the effects of these shifts on terrestrial environments. In this context, the Iberian Peninsula is particularly interesting because of its close proximity to the North Atlantic, although the Iberian interior lacks paleoenvironmental information so far because suitable archives are rare. Here we provide an accurate impression of the last glacial environmental developments in central Iberia based on comprehensive investigations using the upper Tagus loess record. A multi-proxy approach revealed that phases of loess formation during Marine Isotope Stage (MIS) 2 (and upper MIS 3) were linked to utmost aridity, coldness, and highest wind strengths in line with the most intense Greenland stadials also including Heinrich Events 3–1. Lack of loess deposition during the global last glacial maximum (LGM) suggests milder conditions, which agrees with less-cold sea surface temperatures (SST) off the Iberian margin. Our results demonstrate that geomorphological system behavior in central Iberia is highly sensitive to North Atlantic SST fluctuations, thus enabling us to reconstruct a detailed hydrological model in relation to marine–atmospheric circulation patterns.

This study examined whether the promotion of mindfulness in psychotherapists in training can influence the treatment results of their patients. The therapeutic course and treatment results of 196 inpatients, who were treated during a nine week period by nine psychotherapists in training, were compared: in the first phase of the study, the treatment group without (CG, historical control group, n = 55), and in the second phase the treatment group with, (MFG, n = 58) therapists who were currently practicing Zen meditation. The results of treatment were examined (according to the intent-to-treat principle) with the Session Questionnaire for General and Differential Individual Psychotherapy (STEP), the Questionnaire of Changes in Experience and Behaviour (VEV) and the Symptom Checklist (SCL-90-R), and showed significantly better results in the MFG.

The appearances of palaeosurfaces intercalated into palaeo-dune fields on Fuerteventura are multifaceted. Although reddened layers in these dune sediments might suggest that strong soil-formation processes have taken place, the combination of aridity and parent material, namely biogenic carbonate sand of shelf origin, reveals that strong soil formation seems unlikely. These sediments rather represent de- and recalcification processes only. Solely in the case of admixed material of volcanic origin and dust deposits further soil-forming processes seem to be possible. Hematite-rich Saharan dust contributes to reddish colouration of the palaeosurfaces. In addition, CaCO3-coated iron particles appear to be ingredients of dust being leached after deposition and transformed to hematite. Overall, we propose much weaker soil-forming processes during the Pleistocene than previously postulated. Our findings support the relevance of local environments. Carbonate sands of shelf origin hinder strong soil formation and the reddish layers separating dune generations are palaeosurfaces, which mainly consist of Saharan dust. After deposition of allochthonous material, these layers are overprinted by weak soil-forming processes. The formation of palaeosurfaces primarily depends on morphodynamically stable periods during limited sand supply. Our data suggest a cyclicity of processes in the following order: (1) sand accumulation, (2) dust accumulation and weak soil formation, and (3) water-induced erosion. For the Canary Islands, we support the assumption of glacial maxima being periods of increased levels of moisture. In combination with rising sea level, we propose that favorable conditions of surface stability occur immediately after glacial maxima during periods of starting transgression, whereas regression periods immediately after sea-level high stands seem to yield the highest sand supply for the study area.

Titanium–tantalum based alloys can demonstrate a martensitic transformation well above 100 °C, which makes them attractive for shape memory applications at elevated temperatures. In addition, they provide for good workability and contain only reasonably priced constituents. The current study presents results from functional fatigue experiments on a binary Ti–25Ta high-temperature shape memory alloy. This material shows a martensitic transformation at about 350 °C along with a transformation strain of 2 pct at a bias stress of 100 MPa. The success of most of the envisaged applications will, however, hinge on the microstructural stability under thermomechanical loading. Thus, light and electron optical microscopy as well X-ray diffraction were used to uncover the mechanisms that dominate functional degradation in different temperature regimes. It is demonstrated the maximum test temperature is the key parameter that governs functional degradation in the thermomechanical fatigue tests. Specifically, ω-phase formation and local decomposition in Ti-rich and Ta-rich areas dominate when T max does not exceed ≈430 °C. As T max is increased, the detrimental phases start to dissolve and functional fatigue can be suppressed. However, when T max reaches ≈620 °C, structural fatigue sets in, and fatigue life is again deteriorated by oxygen-induced crack formation.

The mechanical properties of porous ceramics are greatly influenced by their microstructure. Therefore, mechanical behavior of highly porous ceramics is different from that of dense ceramics. In this work, we evaluate different mechanical testing methods such as static compression, Brazilian disc test and 3-point bending on their suitability for comparison of highly porous ceramic materials. It is shown that 3-point bending is more suitable than static compression or Brazilian disc testing, as the material exhibits no critical crack propagation under compressive loading. With 3-point bending tests, a quantitative comparison of the mechanical properties of foams with different microstructures and porosities is possible. Under cyclic compression the foams exhibit a very high degree of crack tolerance in combination with preservation of their structural integrity even at high strains of 10%.

Observational results from strong lensing and dynamical modeling indicate that the total density profiles of early-type galaxies are close to isothermal, i.e. ρtot ∝ rγ with γ ≈ −2. To understand the origin of this universal slope we study a set of simulated spheroids formed in cosmological hydrodynamical zoom-in simulations (see Oser et al. 2010 for more details). We find that the total stellar plus dark matter density profiles of all our simulations on average can be described by a power law with a slope of γ ≈ −2.1, with a tendency towards steeper slopes for more compact, lower mass ellipticals, while the total intrinsic velocity dispersion is flat for all simulations, independent of the values of γ. Our results are in good agreement with observations of Coma cluster ellipticals (Thomas et al. 2007) and results from strong lensing (Sonnenfeld et al. 2012). We find that for z ≳ 2 the majority of the stellar build-up occurs through in-situ star formation, i.e. the gas falls to the center of the galaxy and forms stars, causing the galaxy to be more compact and thus the stellar component to be more dominant. As a result, the total density slopes at z ≈ 2 are generally steeper (around γ ≈ −3). Between z = 2 and z = 0 galaxies grow mostly through dry merging, with each merging event shifting the slope more towards γ ≈ −2. We conclude from our simulations that the steepness of the slope of present day galaxies is a signature of the importance of mostly dry mergers in the formation of an elliptical, and suggest that all elliptical galaxies will with time end up in a configuration with a density slope of γ ≈ −2. For a more detailed analysis with a larger sample of simulations see Remus et al. (2013).

The members of the Commission 36 Organizing Committee attending the IAU General Assembly in Rio de Janeiro met for a business session on August 7. Both members from the previous (2006–2009) and the new (2009–2012) Organizing Committee partook in the discussions. Past president John Landstreet described the work he had done over the past three years in terms of supporting proposed conferences on the topic. He has also spent significant amount of time establishing an updated mailing list of all >350 members of the commission, which is unfortunately not provided automatically by the IAU. Such a list is critical for a rapid dissemination of information to the commission members and for a correct and smooth running of elections of IAU officials. Everyone present thanked John effusively for all of his hard work over the past three years to stimulate a high level of activity within the discipline.

Electron microscopy of the composite-forming alloys Ti60Cu14Ni12Sn4Nb10 and Ti60Cu14Ni12Sn4Ta10, shows that for both alloys, the microstructure consists of an array of micron-scale dendrites surrounded by a nanoscale binary eutectic. In the Ta-containing alloy, one of the eutectic phases has been identified as having a bcc crystal structure similar to that of the dendrites. In the Nb-containing alloy, one of the eutectic phases has been found to have a similar composition to that of the dendrites. Further detailed structural and compositional characterization is needed in order to understand the solidification behaviour of such materials. This knowledge may then be used to improve the casting conditions and subsequent mechanical properties of the materials.

Enthalpies of formation were determined for β-sialon phases (Si6–zAlzOzN8–z, z = 0.46 to 3.6) by high-temperature oxidative drop solution calorimetry using an alkali-metal borate (52 wt% LiBo2; 48 wt% NaBO2) solvent. Oxygen gas was bubbled through the melt to accelerate oxidation of the oxynitride samples during dissolution. Sialons near z = 2 appear less stable energetically than ones with higher or lower nitrogen content. A large configurational entropy contribution for sialons with z > 2 may further stabilize these materials. This larger free energy driving form may be the reason for success in pulse-activated processing of these materials. The enthalpies of formation further suggest that a greater driving form for oxynitride formation exists in batch synthesis using SiO2 rather than Al2O3.

The enthalpies of formation of two rare-earth silicates (Y2SiO5 and Yb2SiO5) and a N-containing rare-earth silicate Y10(SiO4)6N2 have been determined using high-temperature drop solution calorimetry. Alkali borate (52 wt% LiBO2·48 wt% NaBO2) solvent was used at 800 °C, and oxygen gas was bubbled through the melt. The nitrogen-containing silicate was oxidized during dissolution. The standard enthalpies of formation are for Y2SiO5, Yb2SiO5, and Y10(SiO4)6N2, respectively, –22868.54 ± 5.34, –22774.75 ± 8.21, and –14145.20 ± 16.48 kJ/mol from elements, and –52.53 ± 4.83, –49.45 6 ± 8.35, and –94.53 ± 11.66 kJ/mol from oxides (Y2O3 or Yb2O3, SiO2) and nitride (Si3N4). The silicates and N-containing silicate are energetically stable with respect to binary oxides and Si3N4, but the N-containing silicate may be metastable with respect to assemblages containing Y2SiO5, Si3N4, and SiO2. A linear relationship was found between the enthalpy of formation of a series of M2SiO5 silicates from binary oxides and the ionic potential (z/r) of the metal cation.