BINA

The synchronization of human networks is essential for our civilization and understanding the motivations, behavior, and basic parameters which govern the dynamics of human networks are important for many aspects of our lives. We studied complex human networks in different configurations with full control over the network connectivity, the coupling strength of each connection and the delay between coupled individuals. Our system is based on coupling violin players in different configurations and measuring the synchronization of their phase, period, frequency and volume. In our system, each player is connecting it's violin output to our computer system and has headphones for the input. We found that humans tend to find a non-trivial solution for frustration situations and spontaneously change the connectivity of the network in order to reach a stable solution. We also found that out-of-phase synchronized state is …

Development of high power devices with improved energy density is a highly desired target for advanced energy storage applications. Herein we propose a new strategy of triply-hybridized supercapacitive energy storage device composed of hybrid battery–supercapacitor negative electrode [Mo6S8 (Chevrel-phase)/Ti3C2 (MXene)] coupled with positive nanoporous carbon electrode, integrated with novel yet unexplored saturated (14 M) aqueous solution of LiCl. The electrochemical stability window of this electrolyte solution (2.70 V) significantly exceeds the cell voltage (2.05 V) relevant for the asymmetrical (hybrid anode vs. carbon cathode) cells. The aqueous 14 M LiCl solution has far superior characteristics to that of the previously studies 21 m LiTFSI aqueous solution. The paper is also focused on a deep electroanalytical analysis of a peculiar redox/capacitive heterogeneity of hybrid electrodes. It establishes …

LepI is a novel multifunctional enzyme that catalyzes stereoselective dehydration, Diels–Alder reaction, and retro-Claisen rearrangement. Here we report the crystal structure of LepI in complex with its co-factor S-adenosyl methionine (SAM). LepI forms a tetramer via the N-terminal helical domain and binds to a SAM molecule in the C-terminal catalytic domain. The binding modes of various LepI substrates are investigated by docking simulations, which suggest that the substrates are bound via both hydrophobic and hydrophilic forces, as well as cation–π interactions with the positively charged SAM. The reaction starts with a dehydration step in which H133 possibly deprotonates the pyridone hydroxyl group of the substrate, while D296 might protonate an alkyl-chain hydroxyl group. Subsequent pericyclization may be facilitated by the correct fold of the substrate's alkyl chain and a thermodynamic driving force …

Nanostructured mixed multi-metal compounds (NCM) based on nickel (Ni), cobalt (Co), and manganese (Mn) are considered as promising electrode materials owing to their multiple valence states, facile accessibility to active sites, and low activation energy for electron transfer. Herein, we demonstrated the fabrication of a hexagonal nanoplate-like architecture of ternary NCM hydroxide with controlled size and composition by a facile one-pot hydrothermal process. The size and composition of the hexagonal NCM nanoplates were controlled by varying the ratio of Ni to (Co + Mn) sources. Accordingly, the maximum capacitance of the optimum NCM is 1188 F g−1 at 1 A g−1 with high rate capacitance due to abundant active sites of the Ni-rich phase and rapid charge transfer kinetics of the nanoplate architecture. By integrating high-capacity Ni-rich NCM hydroxide as a positive electrode with activated carbon as a …

We demonstrate coherent supercontinuum generation (SCG) in a monolithically integrated lithium-niobate waveguide, under the presence of second- and third-order nonlinear effects. We achieve more than two octaves of optical bandwidth in a 0.5-cm-long waveguide with 100-picojoule-level pulses. Dispersion engineering of the waveguide allows for spectral overlap between the SCG and the second harmonic, which enables direct detection of the carrier–envelope offset frequency f_CEO using a single waveguide. We measure the f_CEO of our femtosecond pump source with a 30-dB signal-to-noise ratio.

Li-rich nickel cobalt manganese (NCM) oxides are among the most promising cathode materials for lithium-ion batteries owing to their high specific charges and operating voltages. However, their crystal structures are unstable upon prolonged cycling, leading to a collapse of their electrochemical performance. In this study, we investigated Fe doping of Li-rich NCM materials and explored various Li/Fe ratios. Compared with the reference Li-rich NCM material, the Li1.16(Ni0.18Co0.10Mn0.52Fe0.02)O2 composition exhibited a higher specific charge, potential drop mitigation at fast cycling rates, and an enhanced rate capability. At a rate of 4C, this composition exhibited a specific charge of 150 mA h g−1, which was as much as 50% higher than that of the reference (100 mA h g−1). Neutron and X-ray diffraction data for compounds with different Fe doping concentrations indicated that the crystallographic structure was …

We present a so-called “split-well direct-phonon” active region design for terahertz quantum cascade lasers (THz-QCLs). Lasers based on this scheme profit from both elimination of high-lying parasitic bound states and resonant-depopulation of the lower laser level. Negative differential resistance is observed at room temperature, which indicates that each module behaves as a clean 3-level system. We further use this design to investigate the impact of temperature on the dephasing time of GaAs/AlGaAs THz-QCLs.

The intermittent ‘stick-slip’ dynamics in frictional sliding of solid bodies is common in everyday life and technology. This dynamics has been widely studied on a macroscopic scale, where the thermal motion can usually be neglected. However, the microscopic mechanisms behind the periodic stick-slip events are yet unclear. We employ confocal microscopy of colloidal spheres, to study the frictional dynamics at the boundary between two quasi-two-dimensional (2D) crystalline grains, with a single particle resolution. Such unprecedentedly-detailed observations of the microscopic-scale frictional solid-on-solid sliding have never been previously carried out. At this scale, the particles undergo an intense thermal motion, which masks the avalanche-like nature of the underlying frictional dynamics. We demonstrate that the underlying sliding dynamics involving out-of-plane buckling events, is intermittent and periodic, like …

Export of mRNA transcripts from the cell nucleus is a complex and multistep process, regulated by various proteins and control mechanisms. Recent studies have demonstrated the rapid passage of mRNA–protein complexes (mRNPs) through the nuclear pore complex (NPC) as well as the ability to detect mRNPs stalled at the NPC during inhibition of the mRNA export process. In this chapter, we describe ways to block mRNA export and present an image analysis method to identify mRNPs stuck at the NPC during such blocks. Using the MS2 mRNA-tagging system to track single mRNPs in living cells we are able to examine their intracellular distribution and dynamics both in the nucleoplasm and at the nuclear periphery. We use this method to identify and count the number of static mRNPs anchored to the nuclear envelope under different conditions of mRNA export inhibition.

Nonfunctionalized carbon nanotubes featuring length over than 500 μm, were mixed with an amino-functionalized sol-gel precursor and a highly volatile solvent in order to obtain a well-dispersed solution. Finally, a thickener was added to the nanotubes dispersion thus obtaining a viscous paste, which was deposited on cotton fabrics through knife-over-roll technique thus achieving a surface coating with high electrical conductivity. The as-prepared conductive cotton fabrics were characterized by different chemical-physical techniques and showed a sheet resistance of about 9.5• 102 Ω/sq. Developed conductive fabrics can find applications as conductive material or wearable sensors.

Micro-patterning of a metal organic framework (MOF) from a solution of precursors is achieved by local laser heating. Nano-sized MOFs are formed, followed by rapid assembly due to convective flows around a heat-induced micro-bubble. This laser-induced bottom-up technique is the first to suggest simultaneous synthesis and micro-patterning of MOFs, alleviating the need for pre-preparation and stabilization.

The synthesis of chiral nanoporous carbons based on chiral ionic liquids (CILs) of amino acids as precursors is described. Such unique precursors for the carbonization of CILs yield chiral carbonaceous materials with high surface area (≈620 m2 g−1). The enantioselectivities of the porous carbons are examined by advanced techniques such as selective adsorption of enantiomers using cyclic voltammetry, isothermal titration calorimetry, and mass spectrometry. These techniques demonstrate the chiral nature and high enantioselectivity of the chiral carbon materials. Overall, we believe that the novel approach presented here can contribute significantly to the development of new chiral carbon materials that will find important applications in chiral chemistry, such as in chiral catalysis and separation and in chiral sensors. From a scientific point of view, the approach and results reported here can significantly deepen …

Optical trapping is a powerful optical manipulation technique for controlling various mesoscopic systems that allows formation of tailor-made polymeric micro-sized colloids by directed coalescence of nucleation sites. However, control over the size of a single colloid requires constant monitoring of the growth process and deactivation of the optical trap once it reaches the required dimensions. Moreover, producing more than one colloid requires moving the sample to a pristine location where the process must be repeated. Here, we present a novel method for continuous control over formation of polydimethylsiloxane colloids based on directed coalescence induced by optical traps under flow inside microfluidic channels. Once the drag force on a growing colloid exceeds the trapping force, it leaves the optical trap, and a new colloid starts to form at the same location. We demonstrate repeatability of the process and …

Poly(4,4′-oxybisbenzenamine) (POBBA) and poly(4,4′-oxybisbenzenamine-pyrrole) (COP) with mixed macro–nano sizes were synthesized by a facile one-step reaction using multifunctional carbon dots as the initiator. The two polymers were proven as effective adsorbents for four popular organic dyes in solution: Congo red, crystal violet, methylene blue, and rhodamine B. The adsorption between the adsorbate and the adsorbent was probed by Fourier transform infrared spectroscopy (FTIR). The adsorption mechanism was governed by the pseudo-second-order model, whereas the Freundlich isotherm fitted the adsorption data well for both adsorbent materials.

Although Pb Halide perovskites (HaPs) can be prepared as organic electronic materials, they resemble top-quality inorganic semiconductors, especially with respect to their low defect densities, as derived from optical and electronic transport studies. Among causes for such low defect densities were ‘defect-tolerance’ (proposed) and ‘self-healing’ (experimentally identified). We show that HaPs are likely an example of a class of materials that cannot support static bulk defect densities significantly above thermodynamically-dictated densities. The reasons are (a) the free energy to form HaPs (from binary halides) is less than the formation energies of (static) defects in them and (b) the small kinetic stabilization of such defects. We summarize the evidence for such a situation and conclude that higher defect densities in polycrystalline films likely result from the (expected) smaller defect formation energy at surfaces and …