BINA

The increasing interest and need to shift to sustainable energy give rise to the utilization of fuel cell technologies in various applications. The challenging task of hydrogen storage and transport led to the development of liquid hydrogen carriers (LHCs) as fuels for direct LHC fuel cells, such as methanol in direct methanol fuel cells (DMFCs). Although simpler to handle, most direct LHC fuel cells suffer from durability and price issues derived from high catalysts’ loadings and byproducts of the oxidation reaction of the fuel. Herein, we report on the development of direct hydroquinone fuel cells (DQFCs) based on anthraquinone-2,7-disulfonic acid (AQDS) as an LHC. We have shown that DQFC can operate with a continuous flow of quinone as a hydrogen carrier, outperforming the incumbent state-of-the-art DMFC by a factor of 3 in peak power density while completely removing the need for any catalyst at the anode. In …

Wilms’ tumors are pediatric malignancies that are thought to arise from faulty kidney development. They contain a wide range of poorly differentiated cell states resembling various distorted developmental stages of the fetal kidney, and as a result, differ between patients in a continuous manner that is not well understood. Here, we used three computational approaches to characterize this continuous heterogeneity in high-risk blastemal-type Wilms’ tumors. Using Pareto task inference, we show that the tumors form a triangle-shaped continuum in latent space that is bounded by three tumor archetypes with “stromal”,“blastemal”, and “epithelial” characteristics, which resemble the un-induced mesenchyme, the cap mesenchyme, and early epithelial structures of the fetal kidney. By fitting a generative probabilistic “grade of membership” model, we show that each tumor can be represented as a unique mixture of three hidden “topics” with blastemal, stromal, and epithelial characteristics. Likewise, cellular deconvolution allows us to represent each tumor in the continuum as a unique combination of fetal kidney-like cell states. These results highlight the relationship between Wilms’ tumors and kidney development, and we anticipate that they will pave the way for more quantitative strategies for tumor stratification and classification.

Neuroblastoma is a lethal childhood solid tumor of developing peripheral nerves. Two percent of children with neuroblastoma develop Opsoclonus Myoclonus Ataxia Syndrome (OMAS), a paraneoplastic disease characterized by cerebellar and brainstem-directed autoimmunity, but typically with outstanding cancer-related outcomes. We compared tumor transcriptomes and tumor infiltrating T- and B-cell repertoires from 38 OMAS subjects with neuroblastoma to 26 non-OMAS associated neuroblastomas. We found greater B- and T-cell infiltration in OMAS-associated tumors compared to controls, but unexpectedly showed that both were polyclonal expansions. Tertiary lymphoid structures (TLS) were enriched in OMAS-associated tumors. We identified significant enrichment of the MHC Class II allele HLA-DOB*01:01 in OMAS patients. OMAS severity scores were associated with the expression of several candidate autoimmune genes. We propose a model in which polyclonal autoreactive B lymphocytes act as antigen presenting cells and drive TLS formation, thereby crucially supporting both sustained polyclonal T-cell-mediated anti-tumor immunity and paraneoplastic OMAS neuropathology.

Particle hopping is a common feature in heterogeneous media. We explore such motion by using the widely applicable formalism of the continuous time random walk and focus on the statistics of rare events. Numerous experiments have shown that the decay of the positional probability density function P (X, t), describing the statistics of rare events, exhibits universal exponential decay. We show that such universality ceases to exist once the threshold of exponential distribution of particle hops is crossed. While the mean hop is not diverging and can attain a finite value; the transition itself is critical. The exponential universality of rare events arises due to the contribution of all the different states occupied during the process. Once the reported threshold is crossed, a single large event determines the statistics. In this realm, the big jump principle replaces the large deviation principle, and the spatial part of the decay is unaffected by the temporal properties of rare events.

Background & AimsHepatocellular carcinoma (HCC) is a model of a diverse spectrum of cancers because it is induced by well-known etiologies, mainly hepatitis C virus (HCV) and hepatitis B virus. Here, we aimed to identify HCV-specific mutational signatures and explored the link between the HCV-related regional variation in mutations rates and HCV-induced alterations in genome-wide chromatin organization.MethodsTo identify an HCV-specific mutational signature in HCC, we performed high-resolution targeted sequencing to detect passenger mutations on 64 HCC samples from 3 etiology groups: hepatitis B virus, HCV, or other. To explore the link between the genomic signature and genome-wide chromatin organization we performed chromatin immunoprecipitation sequencing for the transcriptionally permissive H3K4Me3, H3K9Ac, and suppressive H3K9Me3 modifications after HCV infection.Results …

Thermal effects are well known to influence the electronic and optical properties of materials through several physical mechanisms and are the basis for various optoelectronic devices. The thermo-optic (TO) effect-the refractive index variation with temperature (dn/dT), is one of the common mechanisms used for tunable optical devices, including integrated optical components, metasurfaces and nano-antennas. However, when a static and fixed operation is required, ie, temperature invariant performance-this effect becomes a drawback and may lead to undesirable behavior through drifting of the resonance frequency, amplitude, or phase, as the operating temperature varies over time. In this work, we present a systematic approach to mitigate thermally induced optical fluctuations in nanophotonic devices. By using hybrid subwavelength resonators composed from two materials with opposite TO dispersions (dn/dT< 0 …

Particle hopping is a common feature in heterogeneous media. We explore such motion by using the widely applicable formalism of the continuous time random walk and focus on the statistics of rare events. Numerous experiments have shown that the decay of the positional probability density function P (X, t), describing the statistics of rare events, exhibits universal exponential decay. We show that such universality ceases to exist once the threshold of exponential distribution of particle hops is crossed. While the mean hop is not diverging and can attain a finite value; the transition itself is critical. The exponential universality of rare events arises due to the contribution of all the different states occupied during the process. Once the reported threshold is crossed, a single large event determines the statistics. In this realm, the big jump principle replaces the large deviation principle, and the spatial part of the decay is unaffected by the temporal properties of rare events.

During embryonic development, mutually antagonistic signaling cascades determine gonadal fate toward a testicular or ovarian identity. Errors in this process result in disorders of sex development (DSDs), characterized by discordance between chromosomal, gonadal, and anatomical sex. The absence of an appropriate, accessible in vitro system is a major obstacle in understanding mechanisms of sex-determination/DSDs. Here, we describe protocols for differentiation of mouse and human pluripotent cells toward gonadal progenitors. Transcriptomic analysis reveals that the in vitro–derived murine gonadal cells are equivalent to embryonic day 11.5 in vivo progenitors. Using similar conditions, Sertoli-like cells derived from 46,XY human induced pluripotent stem cells (hiPSCs) exhibit sustained expression of testis-specific genes, secrete anti-Müllerian hormone, migrate, and form tubular structures. Cells derived …

Colloidal semiconductor nanocrystals have attracted much interest due to their unique optical properties, with applications ranging from displays to biomedical imaging. Nanocrystal optical properties depend on the structure of the surface, where defects can lead to traps. CdSe nanocrystals undergo surface reorganization, or self-healing, to eliminate defects, removing midgap traps from the band structure. However, the effect of this process on the optical spectrum is not well studied. Here, we show that self-healing not only eliminates midgap traps from the band structure but also brightens the spectrum and causes the excitonic states to emerge as the dominant features, in agreement with experimental annealing studies. We find that self-healing can lead to new traps like bonded Se–Se or Cd–Cd dimers, and their behavior is different from that of undercoordinated atom traps. These results suggest that eliminating …

This review describes the use of Electron Paramagnetic Resonance (EPR) to measure residue specific dynamics in proteins with a specific focus on Cu(II)‐based spin labels. First, we outline approaches used to measure protein motion by nitroxide‐based spin labels. Here, we describe conceptual details and outline challenges that limit the use of nitroxide spin labels to solvent‐exposed α‐helical sites. The bulk of this review showcases the use of newly developed Cu(II)‐based protein labels. In this approach, the strategic mutation of native residues on a protein to generate two neighboring Histidine residues (i.e., the dHis motif) is exploited to enable a rigid site‐selective binding of a Cu(II) complex. The chelation of the Cu(II) complex to dHis directly anchors the Cu(II) spin label to the protein backbone. The improvement in rigidity expands both the spin‐labeling toolkit as well as the resolution of many EPR …

This review describes the use of Electron Paramagnetic Resonance (EPR) to measure residue specific dynamics in proteins with a specific focus on Cu(II)‐based spin labels. First, we outline approaches used to measure protein motion by nitroxide‐based spin labels. Here, we describe conceptual details and outline challenges that limit the use of nitroxide spin labels to solvent‐exposed α‐helical sites. The bulk of this review showcases the use of newly developed Cu(II)‐based protein labels. In this approach, the strategic mutation of native residues on a protein to generate two neighboring Histidine residues (i.e., the dHis motif) is exploited to enable a rigid site‐selective binding of a Cu(II) complex. The chelation of the Cu(II) complex to dHis directly anchors the Cu(II) spin label to the protein backbone. The improvement in rigidity expands both the spin‐labeling toolkit as well as the resolution of many EPR …

Efficient and stable electrocatalysts are critically needed for the development of practical overall seawater splitting. The nanocomposite of RuCoBO has been rationally engineered to be an electrocatalyst that fits these criteria. The study has shown that a calcinated RuCoBO-based nanocomposite (Ru2Co1BO-350) exhibits an extremely high catalytic activity for H2 and O2 production in alkaline seawater (overpotentials of 14 mV for H2 evolution and 219 mV for O2 evolution) as well as a record low cell voltage (1.466 V@10 mA cm–2) and long-term stability (230 h @50 mA cm–2 and @100 mA cm–2) for seawater splitting. The results show that surface reconstruction of Ru2Co1BO-350 occurs during hydrogen evolution reaction and oxygen evolution reaction, which leads to the high activity and stability of the catalyst. The reconstructed surface is highly resistant to Cl– corrosion. The investigation suggests that a new …

Metal transcription factors regulate metal concentrations in eukaryotic and prokaryotic cells. Copper is a metal ion that is being tightly regulated, owing to its dual nature. Whereas copper is an essential nutrient for bacteria, it is also toxic at high concentrations. CopY is a metal-sensitive transcription factor belonging to the copper-responsive repressor family found in Gram-positive bacteria. CopY represses transcription in the presence of Zn(II) ions and initiates transcription in the presence of Cu(I) ions. The complete crystal structure of CopY has not been reported yet, therefore most of the structural information on this protein is based on its similarity to the well-studied MecI protein. In this study, electron paramagnetic resonance (EPR) spectroscopy was used to characterize structural and local dynamical changes in Streptococcus pneumoniae CopY as a function of Zn(II), Cu(I), and DNA binding. We detected different …

The short time (large energy) behavior of the Sachdev-Ye-Kitaev model (SYK) is one of the main reasons for the growing interest garnered by this model. True chaotic behavior sets in at the Thouless time, which can be extracted from the energy spectrum. In order to do so, it is necessary to unfold the spectrum, ie, to filter out global tendencies. Using a simple ensemble average for unfolding results in a parametically low estimation of the Thouless energy. By examining the behavior of the spectrum as the distribution of the matrix elements is changed into a log-normal distribution, it is shown that the sample-to-sample level spacing variance determines this estimation of the Thouless energy. Using the singular value decomposition method, which filters out these global sample-to-sample fluctuations, the Thouless energy becomes parametrically much larger, essentially of the order of the band width. It is shown that the …

Metal transcription factors regulate metal concentrations in eukaryotic and prokaryotic cells. Copper is a metal ion that is being tightly regulated, owing to its dual nature. Whereas copper is an essential nutrient for bacteria, it is also toxic at high concentrations. CopY is a metal-sensitive transcription factor belonging to the copper-responsive repressor family found in Gram-positive bacteria. CopY represses transcription in the presence of Zn(II) ions and initiates transcription in the presence of Cu(I) ions. The complete crystal structure of CopY has not been reported yet, therefore most of the structural information on this protein is based on its similarity to the well-studied MecI protein. In this study, electron paramagnetic resonance (EPR) spectroscopy was used to characterize structural and local dynamical changes in Streptococcus pneumoniae CopY as a function of Zn(II), Cu(I), and DNA binding. We detected different …

Under ultrasonication, cuprous oxide (Cu2O) microparticles (<5 µm) were fragmented into nanoparticles (NPs, ranging from 10 to 30 nm in diameter), and interacted strongly with alkali lignin (Mw = 10 kDa) to form a nanocomposite. The ultrasonic wave generates strong binding interaction between lignin and Cu2O. The L-Cu nanocomposite exhibited synergistic effects with enhanced antibiofilm activities against E. coli, multidrug-resistant (MDR) E. coli, S. aureus (SA), methicillin-resistant SA, and P. aeruginosa (PA). The lignin-Cu2O (L-Cu) nanocomposite also imparted notable eradication of such bacterial biofilms. Experimental evidence unraveled the destruction of bacterial cell walls by L-Cu, which interacted strongly with the bacterial membrane. After exposure to L-Cu, the bacterial cells lost the integrated structural morphology. The estimated MIC for biofilm inhibition for the five tested pathogens was 1 mg …

Being nearly unlimited natural resource containing mostly Na cations, the use of seawater as an electrolyte solution (aka seawater batteries) for electrochemical energy storage has received growing attention. To date, the vast majority of studies have focused on the use of seawater in Na-metal batteries protected by ion-conductive membranes hermetic to water. These systems, however, are complex and expensive, and suffer from a short cycling life. Here, we present alternative seawater batteries that utilize polyimide anodes. With its high capacity of more than 140 mAh/g, impressive rate capability, and excellent long-term stability (98% capacity retention after more than 9000 cycles), the prepared polyimide electrodes demonstrated to be promising candidate anodes for seawater electrochemical energy storage devices. Looking for a suitable cathode, we explored the use of nickel hexacyanoferrate (Ni-HCF) and …

We study optimal restart times for the quantum first hitting time problem. Using a monitored one-dimensional lattice quantum walk with restarts, we find an instability absent in the corresponding classical problem. This instability implies that a small change in parameters can lead to a rather large change of the optimal restart time. We show that the optimal restart time versus a control parameter, exhibits sets of staircases and plunges. The plunges, are due to the mentioned instability, which in turn is related to the quantum oscillation of the first hitting time probability, in the absence of restarts. Furthermore, we prove that there are only two patterns of the staircase structures, dependent on the parity of the distance between the target and source in units of lattice constant.

Superhydrophobic surface preparation is developed by inspiration from nature. As it is a natural fact that lotus leaves are water repellant, thus researchers tried their best to develop superhydrophobic coatings by using several materials. The materials are categorized by inorganic, organic, and their synergistic hybrids. Polymeric coatings are more usable by scientists because of its tunable chemical features and their internal morphologies. This chapter will discuss in brief the coating materials and how polymer systems influenced the superhydrophobicity.

Opto-electronic oscillators are sources of microwave-frequency tones that may reach very low noise levels. Much effort is being dedicated to the realization of oscillators based on photonic integrated devices. In this work, we propose and demonstrate a thermo-elastic opto-electronic oscillator at 2.213 GHz frequency based on a standard silicon-photonic integrated circuit. A microwave-frequency electrical signal modulates an optical pump wave carrier. The modulated waveform launches surface acoustic waves in a silicon-on-insulator substrate, through absorption in a metallic grating and thermo-elastic actuation. The waveform is reconverted to the optical domain through photoelastic modulation of an optical probe wave carrier in a standard racetrack resonator waveguide. Both the thermo-elastic actuation and the photoelastic modulation are radio-frequency selective. The output probe wave is detected, and the receiver voltage is amplified and fed back to modulate the optical pump input. Sufficient gain drives the loop into oscillations. The oscillator does not involve piezoelectricity and can be realized on any substrate. Long acoustic delays may be implemented in compact devices. The frequency of operation is scalable to tens of GHz. The principle may be useful in integrated microwave-photonic signal processing and in the elastic analysis of surfaces and thin layers.