Artificial system inspired by climbing mechanism of galium aparine fabricated via 3D laser lithography

In this work, we present an artificial dry adhesive system inspired by the leaf-climbing mechanisms in Galium aparine. Among the different species of climbing plants, G. aparine shows a unique capability of adhesion to a wide range of roughness and stiffness objects, mainly via its leaves, using microscopic hooks for the physical interlocking. The adaxial (upper) and abaxial (lower) leaf surfaces differ significantly in attachment properties, which depend on the direction of the applied force (ratchet-like mechanism). In order to mimic this adhesive behavior, we designed artificial abaxial and adaxial leaf hooks by extracting the morphological parameters from the natural structures. We fabricated artificial hooks at different scales (1:1, 1:2, 1:4) using Direct Laser Lithography (DLL), a technique that allows a rapid prototyping of 3D microstructures. The adhesion of the artificial systems was tested on a polyester tissue substrate, obtaining adhesive forces comparable or higher than the natural counterpart. This biomimetic approach can open new opportunities to understand nature through artificial investigations and lead to several applications in the fields of robotics and space technology

SYNE1 ataxia is a common recessive ataxia with major non-cerebellar features: A large scale multi-centre study.

Mutations in the synaptic nuclear envelope protein 1 (SYNE1) gene have been reported to cause a relatively pure, slowly progressive cerebellar recessive ataxia mostly identified in Quebec, Canada. Combining next-generation sequencing techniques and deep-phenotyping (clinics, magnetic resonance imaging, positron emission tomography, muscle histology), we here established the frequency, phenotypic spectrum and genetic spectrum ofSYNE1in a screening of 434 non-Canadian index patients from seven centres across Europe. Patients were screened by whole-exome sequencing or targeted panel sequencing, yielding 23 unrelated families with recessive truncatingSYNE1mutations (23/434 = 5.3%). In these families, 35 different mutations were identified, 34 of them not previously linked to human disease. While only 5/26 patients (19%) showed the classicalSYNE1phenotype of mildly progressive pure cerebellar ataxia, 21/26 (81%) exhibited additional complicating features, including motor neuron features in 15/26 (58%). In three patients, respiratory dysfunction was part of an early-onset multisystemic neuromuscular phenotype with mental retardation, leading to premature death at age 36 years in one of them. Positron emission tomography imaging confirmed hypometabolism in extra-cerebellar regions such as the brainstem. Muscle biopsy reliably showed severely reduced or absent SYNE1 staining, indicating its potential use as a non-genetic indicator for underlyingSYNE1mutations. Our findings, which present the largest systematic series of SYNE1 patients and mutations outside Canada, revise the view that SYNE1 ataxia causes mainly a relatively pure cerebellar recessive ataxia and that it is largely limited to Quebec. Instead, complex phenotypes with a wide range of extra-cerebellar neurological and non-neurological dysfunctions are frequent, including in particular motor neuron and brainstem dysfunction. The disease course in this multisystemic neurodegenerative disease can be fatal, including premature death due to respiratory dysfunction. With a relative frequency of ∼5%, SYNE1 is one of the more common recessive ataxias worldwide