Chimeras in the two-community Kuramoto model with an external drive

We study the bifurcations of a special case of the Kuramoto model with two communities of oscillators and an external drive. We use Ott-Antonsens ansatz to derive the low-dimensional system of differential equations that governs the macroscopic dynamics of the high-dimensional problem. The choice of parameters of the system is motivated by the search for so-called Chimera states; stable phase configurations with partial synchronization. Our main result is the derivation of the low-dimensional system following Ott-Antonsens Ansatz and findings of periodic and chaotic Chimeras

Ultrafast band structure control of a two-dimensional heterostructure

The electronic structure of two-dimensional (2D) semiconductors can be signicantly altered by screening effects, either from free charge carriers in the material itself, or by environmental screening from the surrounding medium. The physical properties of 2D semiconductors placed in a heterostructure with other 2D materials are therefore governed by a complex interplay of both intra- and inter-layer interactions. Here, using time- and angle-resolved photoemission, we are able to isolate both the layer-resolved band structure and, more importantly, the transient band structure evolution of a model 2D heterostructure formed of a single layer of MoS 2 on graphene. Our results reveal a pronounced renormalization of the quasiparticle gap of the MoS 2 layer. Following optical excitation, the band gap is reduced by up to ∼400 meV on femtosecond timescales due to a persistence of strong electronic interactions despite the environmental screening by the n-doped graphene. This points to a large degree of tuneability of both the electronic structure and electron dynamics for 2D semiconductors embedded in a van der Waals-bonded heterostructure.PostprintPeer reviewe

Quantitative phosphoproteomics of cytotoxic T cells to reveal Protein Kinase D 2 regulated networks

The focus of the present study was to characterize the phosphoproteome of cytotoxic T cells and to explore the role of the serine threonine kinase PKD2 (Protein Kinase D2) in the phosphorylation networks of this key lymphocyte population. We used Stable Isotope Labeling of Amino acids in Culture (SILAC) combined with phosphopeptide enrichment and quantitative mass-spectrometry to determine the impact of PKD2 loss on the cytotoxic T cells phosphoproteome. We identified 15,871 phosphorylations on 3505 proteins in cytotoxic T cells. 450 phosphosites on 281 proteins were down-regulated and 300 phosphosites on 196 proteins were up-regulated in PKD2 null cytotoxic T cells. These data give valuable new insights about the protein phosphorylation networks operational in effector T cells and reveal that PKD2 regulates directly and indirectly about 5% of the cytotoxic T-cell phosphoproteome. PKD2 candidate substrates identified in this study include proteins involved in two distinct biological functions: regulation of protein sorting and intracellular vesicle trafficking, and control of chromatin structure, transcription, and translation. In other cell types, PKD substrates include class II histone deacetylases such as HDAC7 and actin regulatory proteins such as Slingshot. The current data show these are not PKD substrates in primary T cells revealing that the functional role of PKD isoforms is different in different cell lineages

Phenotype and genotype of 87 patients with Mowat-Wilson syndrome and recommendations for care

Mowat-Wilson syndrome (MWS) is a rare intellectual disability/multiple congenital anomalies syndrome caused by heterozygous mutation of the ZEB2 gene. It is generally underestimated because its rarity and phenotypic variability sometimes make it difficult to recognize. Here, we aimed to better delineate the phenotype, natural history, and genotype-phenotype correlations of MWS.MethodsIn a collaborative study, we analyzed clinical data for 87 patients with molecularly confirmed diagnosis. We described the prevalence of all clinical aspects, including attainment of neurodevelopmental milestones, and compared the data with the various types of underlying ZEB2 pathogenic variations.ResultsAll anthropometric, somatic, and behavioral features reported here outline a variable but highly consistent phenotype. By presenting the most comprehensive evaluation of MWS to date, we define its clinical evolution occurring with age and derive suggestions for patient management. Furthermore, we observe that its severity correlates with the kind of ZEB2 variation involved, ranging from ZEB2 locus deletions, associated with severe phenotypes, to rare nonmissense intragenic mutations predicted to preserve some ZEB2 protein functionality, accompanying milder clinical presentations.ConclusionKnowledge of the phenotypic spectrum of MWS and its correlation with the genotype will improve its detection rate and the prediction of its features, thus improving patient care.GENETICS in MEDICINE advance online publication, 4 January 2018; doi:10.1038/gim.2017.221

Phenotype and genotype of 87 patients with Mowat–Wilson syndrome and recommendations for care

Purpose: Mowat–Wilson syndrome (MWS) is a rare intellectual disability/multiple congenital anomalies syndrome caused by heterozygous mutation of the ZEB2 gene. It is generally underestimated because its rarity and phenotypic variability sometimes make it difficult to recognize. Here, we aimed to better delineate the phenotype, natural history, and genotype–phenotype correlations of MWS. Methods: In a collaborative study, we analyzed clinical data for 87 patients with molecularly confirmed diagnosis. We described the prevalence of all clinical aspects, including attainment of neurodevelopmental milestones, and compared the data with the various types of underlying ZEB2 pathogenic variations. Results: All anthropometric, somatic, and behavioral features reported here outline a variable but highly consistent phenotype. By presenting the most comprehensive evaluati

Enhanced promotion of Ru-based ammonia catalysts by <i>in situ</i> dosing of Cs

Ammonia synthesis via the high-temperature and -pressure Haber–Bosch (HB) process at large centralized facilities has a significant contribution to global CO2 emissions. Radically new catalysts should be discovered to enable sustainable ammonia synthesis processes that can operate at much lower temperatures to relax the demand for high pressure in the current HB process. In this manner, the capital requirement and energy consumption for making ammonia would decrease considerably and a de-centralized production could become feasible. Herein, we present a new class of ruthenium-based catalysts promoted with metallic cesium using an in situ preparation technique. The catalysts prepared with this new technique showed up to a factor of ∼10 higher activity compared to the ones prepared by traditional ex situ promotion methods. The in situ promoted catalyst also has a smaller apparent activation energy and is less susceptible to H2 poisoning. We systematically investigate the promotional role of in situ dosed Cs and propose a detailed model supported by extensive density functional theory calculations to explain the difference between the promotional effect of the in situ and traditionally ex situ prepared catalysts