BINA

Single atom platinum catalysts, characterized by isolated Pt atoms dispersed on suitable supports, exhibit high hydrogen evolution catalytic mass activity. The activity is usually limited by the low density of Pt atoms on the substrate. Herein, we report on a single step synthesis from organometallic precursors of Ni and Pt which yields a high density of Pt atoms on Ni nanoparticles dispersed on carbon support. The spontaneous formation of Pt single atoms on the surface of Ni has not been reported in a single step reaction and is a unique feature of the organometallic route. This route allowed us to increase the atomic ratio of single Pt atoms to Ni up to 10% compared to 2% in previous reports. Single Pt atoms on Ni catalyst display high hydrogen evolution reaction activity of 660 mA/mgPt (9 times more than commercial Pt) and stability as HER catalysts compared with commercial Pt/C catalysts.

Simultaneous field- and aperture-plane (back-focal plane, BFP) imaging enriches the information content of fluorescence microscopy. In addition to the usual density and concentration maps of sample-plane images, BFP images provide information on the surface proximity and orientation of molecular fluorophores. They also give access to the refractive index of the fluorophore-embedding medium. However, in the high-NA, wide-field detection geometry commonly used in single-molecule localisation microscopies, such measurements are averaged over all fluorophores present in the objective’s field of view, thus limiting spatial resolution and specificity. We here solve this problem and demonstrate how an oblique, variable-angle, coherent ring illumination can be used to generate a Bessel beam that - for supercritical excitation angles - produces an evanescent needle of light. Scanning the sample through the this …

Chronic inflammatory diseases, like rheumatoid arthritis (RA) have been described to cause central nervous system (CNS) activation. Less is known about environmental factors that enable the CNS to suppress peripheral inflammation in RA. Here, we identified gut microbiota-derived histamine as such factor. We show that low levels of histamine activate the enteric nervous system, increase inhibitory neurotransmitter concentrations in the spinal cord and restore homeostatic microglia, thereby reducing inflammation in the joints. Selective histamine 3 receptor (H3R) signaling in the intestine is critical for this effect, as systemic and intrathecal application did not show effects. Microglia depletion or pharmacological silencing of local nerve fibers impaired oral H3R agonist-induced pro-resolving effects on arthritis. Moreover, therapeutic supplementation of the SCFA propionate identified one way to expand local intestinal histamine concentrations in mice and humans. Thus, we define a gut-CNS-joint axis pathway where microbiota-derived histamine initiates the resolution of arthritis via the CNS.

The testis is responsible for sperm production and androgen synthesis. Abnormalities in testis development and function lead to disorders of sex development and male infertility. Currently, no in vitro system exists for modelling the testis. Here, we generated testis organoids from neonatal mouse primary testicular cells using transwell inserts and show that these organoids generate tubule-like structures and cellular organization resembling that of the in vivo testis. Gene expression analysis of organoids demonstrates a profile that recapitulates that observed in in vivo testis. Embryonic testicular cells, but not adult testicular cells are also capable of forming organoids. These organoids can be maintained in culture for 8-9 weeks and shows signs of entry into meiosis. We further developed defined media compositions that promote the immature versus mature Sertoli cell and Leydig cell states, enabling organoid …

Gold nanorods with small dimensions demonstrate better cellular uptake and absorption efficiency. The ability to synthesize gold nanorods while maintaining a tunable high aspect ratio is challenging as it requires careful control of reaction conditions, often employing additional steps such as pH modification or the use of polymeric additives. We demonstrate a seedless approach for the synthesis of mini (width < 10 nm) gold nanorods with tunable longitudinal surface plasmon resonance from ∼700 nm to >1000 nm and aspect ratios ranging from ∼3 to ∼7 without the use of any polymeric additives or pH modification. A single mild reducing agent, hydroquinone, allowed for up to ∼98% reaction yield from a gold precursor. A mechanism for elongation is proposed based on partial silver decoupling from the reaction. Finally, the particles were coated with various capping agents to allow functionalization and …

The enteric nervous system (ENS) senses microbiota-derived signals and orchestrates mucosal immunity and epithelial barrier functions, in health and disease. However, mechanistic dissections of intestinal neuro-immune-microbiota communications remain challenging and existing research methods limit experimental controllability and throughput. Here, we present a novel optogenetics-integrated gut organ culture system that enables real-time, whole-tissue stimulation of specific ENS lineages, allowing for detailed analysis of their functional impact. We demonstrate that optogenetic activation of enteric cholinergic neurons rapidly modulates intestinal physiology. Interestingly, distinct neuronal firing patterns differentially modulate neuro-immunological gene expression and epithelial barrier integrity. Furthermore, diverse enteric neuronal lineages exert distinct regulatory roles. While cholinergic activation promotes gene-sets associated with type-2 immunity, tachykininergic enteric neurons differentially control mucosal defense programs. Remarkably, luminal introduction of the immunomodulatory bacterium C. ramosum significantly remodeled cholinergic-induced neuro-immunological transcription. These findings suggest that complex combinatorial signals delivered by gut microbes and enteric neurons are locally integrated to fine-tune intestinal immunity and barrier defense. Collectively, we provide a powerful platform for systematic discovery and mechanistic exploration of functional neuroimmune connections, and their potential modulation by drugs, microbes, or metabolites.

A major hypothesis for the etiology of type 1 diabetes (T1D) postulates initiation by viral infection, leading to double-stranded RNA (dsRNA)-mediated interferon response; however, a causal virus has not been identified. Here we use a mouse model, corroborated with human data, to demonstrate that endogenous dsRNA in beta-cells can lead to a diabetogenic immune response, thus identifying a virus-independent mechanism for T1D initiation. We found that disruption of the RNA editing enzyme ADAR in beta-cells triggers a massive interferon response, islet inflammation and beta-cell failure, with features bearing striking similarity to early-stage human T1D. Glycolysis via calcium enhances the interferon response, suggesting an actionable vicious cycle of inflammation and increased beta-cell workload.

Currently, layered Ni-rich oxides cathodes of LiNi1-xMnyCozO2 (x ≥ 0.8) have gained a major attention for the high energy density Li-ion batteries (LIBs), due to their high specific capacity of ~200 mAh g-1 within the limited voltage. However, the large-scale use of these cathodes is severely limited by the poor structural stability, high surface reactivity, and severe capacity fade resulting from the intergranular micro cracks triggered by large volume changes and formation of rock salts at highly de-lithiated state. Knowing the demand for high specific capacity and high cycling stability, a core-shell oxide material 0.8LiNi0.85Mn0.10Co0.05O2-0.2Li1.2Ni0.16Mn0.56Co0.08O2 (NR-CS) with a core Ni-rich oxide, LiNi0.85Mn0.10Co0.05O2 (NMC85) and an outer shell of Mn-based Li-rich Li1.2Ni0.16Mn0.56Co0.08O2 oxide is synthesized, which delivers an initial discharge capacity of 212 mAh g-1 when cycled at 20 mA g -1 …

A-to-I RNA editing is an important cellular process that modifies genomically encoded information during transcription, to generate various RNA isoforms from a single DNA sequence. It involves the conversion of specific adenosines in the RNA sequence to inosines by ADAR proteins, resulting in their recognition as guanosines by cellular machinery, and as such plays a vital role in neuronal and immune functions. Given the widespread occurrence of A-to-I RNA editing events across the animal kingdom, with thousands to millions of editing sites found in the transcriptomes of organisms such as flies and humans, identifying the critical sites and understanding their in-vivo functions remains a challenging task. Here we show for the first time the physiological importance of a single editing site, found within the extracellular domain of the glutamate-gated chloride channel (GluClα), and bridge the gap between its evolutionary conservation across Drosophila species and its function in shaping the behavior of adult flies. We used genomic editing to ablate editing at this specific site, such that the endogenous channel harbors only the unedited version and used a battery of behavioral paradigms to analyze the effects on various features of adult behavior. We provide evidence that GluClαunedited flies exhibit reduced olfactory responses to both appetitive and aversive odors, as well as impaired pheromone-dependent social interactions, and that editing of this site is required for proper processing of olfactory information in olfactory projection neurons. Our findings demonstrate that evolutionary conservation is a useful criterion to pinpoint which of the many …

In recent years, there has been a lot of interest in biodegradable surface-engineered iron oxide nanoparticles (IONPs) because they could be used in drug delivery and other biomedical fields. This chapter gives an overview of the current state of research on how to make biodegradable IONPs, how to engineer their surfaces, and how to make them work for drug delivery and other biomedical applications. Because these nanoparticles are biodegradable, they will break down and leave the body in a safe way, reducing worries about toxicity. Also, the surface of IONPs can be changed to make them more stable, biocompatible, and able to target specific cells or tissues. This makes it easier for drugs to get to where they need to go. The review talks about how natural polymers, peptides, and targeting ligands are used to change the surface, as well as how these changes affect the physicochemical properties and …

Self‐healing (SH) of (opto)electronic material damage can have a huge impact on resource sustainability. The rising interest in halide perovskite (HaP) compounds over the past decade is due to their excellent semiconducting properties for crystals and films, even if made by low‐temperature solution‐based processing. Direct proof of self‐healing in Pb‐based HaPs is demonstrated through photoluminescence recovery from photodamage, fracture healing and their use as high‐energy radiation and particle detectors. Here, the question of how to find additional semiconducting materials exhibiting SH, in particular lead‐free ones is addressed. Applying a data‐mining approach to identify semiconductors with favorable mechanical and thermal properties, for which Pb HaPs are clear outliers, it is found that the Cs2AuIAuIIIX6, (X = I, Br, Cl) family, which is synthesized and tested for SH. This is the first demonstration of …

The performance of lithium–sulfur (Li–S) rechargeable batteries is strongly dependent on the entrapment of the higher‐order intermediate polysulfides at the sulfur cathode. An attracting way of preventing the polysulfide shuttle is by introducing a polar host which can form a Lewis acid–base complex with polysulfides. Herein, the Li–S battery by incorporating iron sulfides (FeS2) as a polar Lewis acid to entrap higher‐order polysulfides at the cathode center is investigated. FeS2/S cathode demonstrates largely improved retention of capacity compared to C/S cathode (capacity fading per cycle of 0.12% and 0.80% for FeS2/S and C/S respectively) and good rate performance in Li–S batteries compared to conventional carbon–sulfur (C/S) cathode. This is attributed to the decrease in polysulfide dissolution and better retention of active sulfur in the cathode during battery cycling which is due to the polar FeS2 additive …

Super-resolution optical imaging has become a prominent tool in life and material sciences, allowing one to decipher structures at increasingly greater spatial detail. Among the utilized techniques in this field, super-resolution optical fluctuation imaging (SOFI) has proved to be a valuable approach. A major advantage of SOFI is its less restrictive requirements for generating super-resolved images of neighboring nanostructures or molecules, as it only assumes that the detected fluctuating light from neighboring emitters is statistically uncorrelated, but not necessarily separated in time. While most optical super-resolution microscopies depend on signals obtained from fluorescence, they are limited by photobleaching and phototoxicity. An alternative source for optical signals can be acquired by detecting the light scattered from molecules or nanoparticles. However, the application of coherent scattering-based imaging modalities for super-resolution imaging has been considerably limited compared to fluorescence-based modalities. Here, we develop scattering-based super-resolution optical fluctuation imaging (sSOFI), where we utilize the rotation of anisotropic particles as a source of fluctuating optical signals. We discuss the differences in the application of SOFI algorithms for coherent and incoherent imaging modalities, and utilize interference microscopy to demonstrate super-resolution imaging of rotating nanoparticle dimers. We present a theoretical analysis of the relevant model systems, and discuss the possible effects of cusp artifacts and electrodynamic coupling between nearby nano-scatterers. Finally, we apply sSOFI as a label-free novelty …

Verena A. Neufeld opened a general discussion of the paper by Andreas Grüneis: In Table 6 of your article (https://doi. org/10.1039/d4fd00085d), EX top-fcc with CCSD (cT) is 0.41 eV which is similar in magnitude to the (cT)-corr. contribution (− 0.44 eV). How con dent can we be about the EX top and EX fcc comparison at the CCSD (cT) level since full con guration interaction could lower EX top-fcc further?Andreas Grüneis responded: Thank you for raising this important point. On the one hand, we agree that the large triples contribution indicate that higherorder correlation effects could be important. If possible, one should try to apply FCIQMC or other cost-effective and accurate approaches to this system and provide benchmark numbers for CC. On the other hand, the reasonable agreement with the experimentally measured adsorption energy suggests, that higherorder effects could potentially cancel out or are …

Coupling superconducting (SC) contacts to light-emitting layers can lead to remarkable effects, as seen in inorganic quantum-well LEDs with superconducting contacts, where an enhancement in radiative recombination was observed. Additional dramatic effects were theorized if both electrodes are SC, such as correlated emission and 2-photon entanglement. Motivated by this and by the question if proximity induced SC is possible in organic light emitting materials, we studied the electronic properties of stacked SC-organic-SC devices. Our structures consisted of Nb (bottom) and NbN (top) SC electrodes and a spin-coated light emitting semiconductor polymer, MEH-PPV. Sputtering the SC directly on the polymer causes pinhole, which we prevent by ultra-slow deposition of a 5 nm aluminum film, before depositing the top SC in-situ. The Al protects the organic film from damage and pinhole formation, while preserving SC in the top electrodes due to proximity effect between Al and NbN. Electrical transport measurements of the completed junctions indicate that indeed, the top and bottom contacts are superconducting and the protected MEH-PPV layer is pinholefree, as supported by HR-TEM and EDS. Most important, we find that as the temperature is decreased below the critical temperature of the SCs, the device shows evidence for proximity effect in the MEH-PPV and for a Josephson effect in the device.

Tunnel type Na0.44MnO2 (tt-NMO) is a promising cathode for sodium-ion batteries having excellent structural stability, diffusion kinetics, and low cost. However, this cathode is reported to suffer from low initial charge capacity (e.g. ≤60 mA h g-1) due to limited accessibility of sodium ion extraction (0.22 ̶ 0.24 Na+ per formula unit) from the structure which hinders the practical viability of this material in a full battery cell. In this study, we report a tailored tt-NMO structure, synthesized using a two-step facile and scalable process, with >95% yield. Our tt-NMO demonstrated a 1st charge capacity of 110 A h g-1 followed by a 115 mA h g-1 discharge capacity within the potential window of 4 ̶ 1.7V versus Na/Na+. The long-term cycling performance at 0.5C rate and 1C rate (1C = 120 mA h g-1) shows excellent structural integrity for over 400 cycles with >75% capacity retention. We show experimentally and support it by …

Fe single atoms in N‐doped C (Fe‐N‐C) present the most promising replacement for carbon‐supported Pt‐based catalysts for the O2 reduction reaction at the cathode of proton exchange membrane fuel cells (PEMFCs). However, it remains unclear how the I/C ratio affects Fe‐N‐C degradation and the stability of single Fe atom active sites (FeNx). Here, an accelerated stress test (AST) protocol is combined with emerging electrochemical techniques for a porous Fe‐N‐C in PEMFC with a range of I/C ratios. The PEMFC current density degradation rates are found to be comparable; however, with increased I/C ratio the additional FeNx sites accessed are more stable, as shown by their higher active site stability number (electrons passed per FeNx lost) at the end of the AST protocol. Meanwhile, the initial rate of TOF decay is suppressed with increasing I/C. Electrochemical process changes are studied via distribution …

Lignin, an aromatic biopolymer, in the terrestrial lignocellulosic biomass constitutes the single largest and sustainable source of biofuels and biochemicals. The recalcitrant nature of lignin is a hindrance to its chemical or biochemical conversion. Moreover, its insolubility in water too is a major challenge in its quantification which is a necessary step prior to and after its conversion. Though there are celebrated quantification methods like the classical Klason lignin method and the acetyl bromide solubilisation (ABSL) method they are not environmentally friendly as harmful chemicals are used in these processes. State of the art analytical techniques based on NMR, HPLC and GC-MS are also being developed for the quantification of lignin owing to the strategic significance of its detection and estimation. Addressing these issues, herein we report a simple and environmentally friendly method for the quantification of lignin (alkali, low sulfonate content) in a two-step process using water as the solvent for the solubilisation of lignin, which is indeed a breakthrough. Clear aqueous solutions of lignin were obtained by high-speed stirring using an ultra-turrax. The aqueous solutions of lignin showed characteristic absorbance at 306 nm. A linear relationship between the amount of lignin and the absorbance at 306 nm is observed that formed the basis of this novel analytical method for the quantification of lignin.

The progression of kidney damage in chronic kidney disease (CKD) involves multiple post-injury stages and complex cellular and molecular mechanisms that are not yet fully understood. In our study we set to characterize the dynamics of mRNA splicing following kidney injury. To this end, we analyzed publicly available bulk RNA-seq data covering nine time points following a kidney ischemia-reperfusion injury (IRI) mouse experiment. Using topic modeling we discerned five distinct temporal phases corresponding to the following cell states: 'early injury response', 'injury', 'repairing', 'failed recovery', and 'healthy proximal tubule'. Additionally, we discovered a set of genes that are alternatively spliced between selected time points associated with these cell states, some of which are related to injury, stress, EMT, and apoptosis. Finally, we found several putative splicing regulators that are differentially expressed between the different time points and whose binding motifs are enriched in the vicinity of alternatively spliced exons, indicating that they may play critical roles in mRNA splicing dynamics following kidney injury and repair. These findings enhance our understanding of the molecular mechanisms involved in kidney injury and repair, offering potential avenues for developing targeted therapeutic strategies for acute kidney injury (AKI) and its progression to CKD.

Optical properties determine how light interacts with biological tissues. The current methods for measuring these optical properties are influenced by both deep and superficial skin layers. Polarization‐based methods have been proposed in order to determine the influence of deep layer scattering. Polarized light allows for the separation of ballistic photons from diffuse ones, enhancing image contrast and resolution while providing additional tissue information. The Q‐sensing technique captures co‐polarized I∥$$ \left({I}_{\parallel}\right) $$ and cross‐polarized I⊥$$ \left({I}_{\perp}\right) $$ signals, making it possible to isolate the superficial scattering. However, the random structure of tissues leads to rapid depolarization of the polarized light. Detecting where the light becomes depolarized aids in sensing abnormalities within the tissues. Hence, this research focuses on identifying where depolarization occurs …

Zinc metal, with its high theoretical capacity and low cost, stands out as a promising anode material for affordable high energy-density storage technologies in rechargeable batteries. However, obtaining a high level of reversibility in zinc electrodeposition, which is pivotal for the success of rechargeable zinc-metal-based batteries, remains a significant challenge. A critical factor in this regard is the physicochemical characteristics of the electrolyte solution. Previous studies have indicated that adjusting the electrolyte solutions’ composition with additives or co-solvents, along with fine-tuning concentrations and pH levels, can enhance the reversibility and kinetics of Zn deposition/stripping. However, the precise impact of Zn salts counter anions in the electrolyte solutions on these processes is not fully understood yet. Aiming to focus on the key fundamental aspects related to the electrolytes’ influences on the Zn …