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Corticothalamic pathways, responsible for the top-down control of the thalamus, have a canonical organization such that every cortical region sends output from both layer 6 (L6) and layer 5 (L5) to the thalamus. Here we demonstrate a qualitative, region-specific difference in the organization of mouse corticothalamic pathways. Specifically, L5 pyramidal cells of the frontal cortex, but not other cortical regions, establish monosynaptic connections with the inhibitory thalamic reticular nucleus (TRN). The frontal L5–TRN pathway parallels the L6–TRN projection but has distinct morphological and physiological features. The exact spike output of the L5-contacted TRN cells correlated with the level of cortical synchrony. Optogenetic perturbation of the L5–TRN connection disrupted the tight link between cortical and TRN activity. L5-driven TRN cells innervated thalamic nuclei involved in the control of frontal cortex activity. Our data show that frontal cortex functions require a highly specialized cortical control over intrathalamic inhibitory processes.

We present a site-specific elemental analysis of nano-scale patterns whereby the data acquisition is based on Rutherford backscattering spectrometry (RBS). The analysis builds on probing a large ensemble of identical nanostructures. This ensures that a very good limit of detection can be achieved. In addition, the analysis exploits the energy loss effects of the backscattered ions within the nanostructures to distinguish signals coming from different locations of the nanostructures. The spectrum deconvolution is based on ion-trajectory calculations. With this approach, we analyse the Ru area-selective deposition on SiO2-TiN line-space patterns with a linewidth of 35 nm and a pitch of 90 nm. We quantify the selectivity and the Ru local areal density on the top versus on the sidewall of the SiO2 lines. The sensitivity to probe ruthenium deposited on the various surfaces is as low as 1013 atoms/cm2. The analysis is quantitative, traceable, and highly accurate thanks to the intrinsic capabilities of RBS.

In the flourishing field of soft robotics, strategies to embody communication and collective motion are scarce. Here we report the synchronized oscillations of thin plastic actuators by an approach reminiscent of the synchronized motion of pendula and metronomes. Two liquid crystalline network oscillators fuelled by light influence the movement of one another and display synchronized oscillations in-phase and anti-phase in a steady state. By observing entrainment between the asymmetric oscillators we demonstrate the existence of coupling between the two actuators. We qualitatively explain the origin of the synchronized motion using a theoretical model and numerical simulations, which suggest that the motion can be tuned by the mechanical properties of the coupling joint. We thus anticipate that the complex synchronization phenomena usually observed in rigid systems can also exist in soft polymeric materials. This enables the use of new stimuli, featuring an example of collective motion by photo-actuation.

The propagation of blast and shock waves in confined environments is a complex phenomenon; yet, being able to derive valid predictions of such phenomena is highly relevant, for example, when it comes to the assessment of protection of personnel in military environments. This study looks at the propagation of blast waves inside a compound survival shelter. Experimental analyses are performed on a small-scale model of the actual configuration of the shelter subjected to the detonation of an explosive charge at different locations close to its entrance. Pressure-time signals are recorded on a number of locations in the model. A numerical model is also developed to complement the experimental programme, based on the explicit finite element (FE) code LS-DYNA. The recorded experimental data (e.g., pressure and impulse) are compared with the numerical predictions to validate the FE model. The authors discuss two different modelling approaches (the Lagrangian and the MM-ALE formulations) and analyse the influence of using a different number of ambient layers, the advection method, the time-step size, and level of discretisation. The proposed numerical model predicts and captures the relevant stages of the propagation of the shock wave very well, with error levels on the resulting specific impulse always lower than 19% when compared to the experimental observations.

The current knowledge about composite material machining is inadequate for its optimum utilization in many applications owing to the complexity of the phenomena involved in the cutting area. The objective of this study is to investigate the cutting mechanisms during carbon/epoxy composite drilling. It has been found that fiber orientation relative to the cutting direction is a key factor affecting machining results. Orthogonal cutting has helped to understand phenomena involved in the cutting area. The most common mechanisms noted are shearing, bending, and fiber/matrix interface debonding. It has been also noticed that surface quality, temperature fields’ cartographies, and cutting forces change markedly with fiber orientation.

Entomophagy is a common practice in many regions of the world but there are few examples of national regulations that govern insects for human consumption. Where entomophagy is not common, the current regulatory discourse focuses primarily on food safety and consumer protection. In countries where insects contribute to local diets, nature conservation is often an issue of high importance. This paper investigates the variation in the ways in which entomophagy and its related activities are currently regulated in Thailand, Switzerland, Kenya and Canada. Authoritative bodies who are responsible and the roles they play are discussed. Insects have only recently entered into the sustainable food dialogue, but have not yet been incorporated into policy documents and have been largely omitted from regulatory frameworks. Moreover, even in nations where there is a tradition of consuming a variety of insect species, they do not appear explicitly in dietary guidelines. Although food safety is a major concern, it can undermine the importance of nature conservation, traditional food culture, food security, and potential economic development. Thus, entomophagy should be viewed holistically and development of future legislation must take into consideration its multi-dimensional nature.

Na majeure orthopedische ingrepen is het gebruik van LMWH (laagmoleculair gewicht heparine) wereldwijd courant en verantwoord om het risico op veneuze trombo-embolie te verminderen.

The off-specular (diffuse) nuclear resonant reflectivity of synchrotron radiation is a sensitive measure of the lateral autocorrelation of the magnetisation in thin films and multilayers. The width of the diffuse scattering peak measured at an electronically forbidden reflection is inversely proportional to the in-plane correlation length of the magnetisation direction. The average size of the in-plane antiferromagnetic domains is determined in different states of the same Fe/Cr superlattice. The hyperfine magnetic fields in coexisting small and large domains are measured independently.

De roep om verantwoord antibioticagebruik klinkt alsmaar luider; de nadelige gevolgen van antibioticagebruik worden op diverse terreinen dan ook steeds meer aangetoond.

‘Zou u verrast zijn mocht uw patient in de komende 6 tot 12 maanden overlijden?’ Deze surprise question werd meer dan tien jaar geleden ontwikkeld en wereldwijd gebruikt om patienten te identificeren met een verhoogde palliatieve zorgnood.

In vele landen staat de eerstelijnsgezondheidzorg onder druk, onder andere door de toenemende levensverwachting, multimorbiditeit en chroniciteit van zorg. Taakdelegatie van artsen naar verpleegkundigen in de eerste lijn is een belangrijke strategie om deze druk te doen zakken.

Meer dan 90% van de borstkankerpatienten krijgt de diagnose in een vroeg stadium, maar toch sterft uiteindelijk 25% ten gevolge van metastasen op afstand. Vele patienten zoeken dan ook actief naar allerlei soorten manieren om dit risico te verkleinen.

Rutherford backscattering and channeling spectrometry (RBS), photoluminescence (PL) spectroscopy and transmission electron microscopy (TEM) have been used to investigate macroscopic and microscopic segregation in MOCVD grown InGaN layers. The PL peak energy and In content (measured by RBS) were mapped at a large number of distinct points on the samples. An indium concentration of 40%, the highest measured in this work, corresponds to a PL peak of 710 nm, strongly suggesting that the light-emitting regions of the sample are very indium-rich compared to the average measured by RBS. Cross-sectional TEM observations show distinctive layering of the InGaN films. The TEM study further reveals that these layers consist of amorphous pyramidal contrast features with sizes of order 10 nm. The composition of these specific contrast features is shown to be In-rich compared to the nitride matrix.

This experimental study concerns the tribological properties of different carbon/porous silicon carbide couples. The aim of this is to characterize the optimum friction couple (carbon/silicon carbide) for dynamic sealing elements in automotive water pumps. A tribometer was used to determine the wear of these material couples. The parameters able to influence the wear, namely the surface finish of the porous silicon carbide material, the quality of the carbon material, the normal load, the surroundings and the speed (in the case of dynamic friction), have been studied. It is evident from this study that the estimated average wear calculated by an empirical mathematical model is reliable except under conditions of extreme friction.

Crystalline and magnetic structure as well as the interlayer exchange coupling in MBE grown Fe/FeSi multilayers are investigated. From conversion electron Mossbauer spectroscopy and ion beam channeling measurements the spacer FeSi material is found to be stabilized in a crystalline metastable metallic FeSi phase with the CsCl structure. Strong non-oscillatory interlayer exchange coupling is identified with magnetometry and synchrotron Mossbauer reflectometry. From the fits of the time spectrum and the resonant ϕ—ϕ scans a model for the sublayer magnetization of the multilayer is deduced.

A mixed numerical experimental approach is the basis of a new method for the identification of the material damping properties of fibre reinforced polymers, which provides an answer to many problems encountered in experimental damping characterization. Experimental modal parameters, measured on a plate specimen, are compared with corresponding results from a numerical calculation, thus allowing to determine the stiffness and damping properties of the material. The relation between the modal parameters (structural parameters) and the material parameters, is obtained by using a numerical model of the specimen in combination with the modal strain energy method.

Previous reports have described antigens that are recognized on human melanoma cells by autologous cytolytic T lymphocytes (CTL). The genes coding for a number of these antigens have been identified. Here we report the cloning of a gene that codes for an antigen recognized by autologous CTL on a human renal carcinoma cell line. This antigen is presented by HLA-B7 and is encoded by a new gene that we have named RAGE1. No expression of RAGE1 was found in normal tissues other than retina. RAGE1 expression was found in only one of 57 renal cell carcinoma samples, and also in some sarcomas, infiltrating bladder carcinomas, and melanomas. This represents the first identification of an antigen recognized by autologous CTL on a renal tumor.

We have shown through Mossbauer spectroscopy that the electric field gradient (EFG), associated with an atomic defect, is sensitive to the bending of ultrathin Si crystals. The changes in the EFG depend on the bending direction. A direct application is the derivation of the orientation of defects that are located in the crystal's surface region. We have used this observation for determining the configuration of Co dimers in Si. Based on the bending experiments, the pair axis is found to point in the direction with respect to the host lattice.

A new spectrum component is observed in Mossbauer spectra of thin body centered cubic Co layers prepared in Fe/Co superlattices doped with57Co. It is characterized by a large magnetic hyperfine field (31.2 T) and an isomer shift nearly equal to that of α-Fe. The decrease of the isomer shift in bcc Co with respect to hcp Co is consistent with smaller s to d charge transfer in bcc Co as compared to hcp Co. The cubic structure of the CoFe superlattices is evidenced with X-ray diffraction and ion-channeling measurements. The Fe/Co interface is investigated with conversion electron Mossbauer spectroscopy. It is shown that the interface alloy thickness is about six monolayers for growth temperatures up to 450 K and that increasing alloying occurs for higher growth temperatures.

We compare both the strain and damage that 100 keV Si irradiation at room temperature introduces in pseudomorphic and relaxed GexSi1−x films grown on Si(100) substrates. The ion range is such that the Si/GexSi1−x interface is not significantly damaged. The amount of damage produced in pseudomorphic and relaxed GexSi1−x layers of similar x for irradiation doses up to 2.5 × 1014 Si/cm2 is the same, which proves that a pre-existing uniform strain does not noticeably affect the irradiation-induced damage. However, the irradiation-induced strain does depend on the pre-existing strain of the samples. Possible interpretations are discussed.