Organofunctionalized borotungstate polyoxometalates as tunable photocatalysts for oxidative dimerization of amines.

Organofunctionalized borotungstate Keggin polyoxometalates, ( BuN)H[HBWO(P(O)Ph)] (PBW), ( BuN)H[HBWO(As(O)Ph)] (AsBW), and ( BuN)[HBWO(PhSiOSiPh)] (SiBW), were synthesized and structurally characterized. Cyclic voltammetry showed that the electronic properties of the clusters are dependent on the nature of the appended main group atoms (P, As, or Si). The first reduction potentials were found to shift positively with respect to that of the unmodified parent species ( BuN)[BWO], with PBW showing the largest shift at +100 mV.

Ferric quinate (QPLEX) interacts with the major outer membrane protein (MOMP) of and enters through the porin channel into the periplasmic space.

Ferric chelates like ferric tyrosinate (TYPLEX) and the closely related ferric quinate (QPLEX) are structural mimics of bacterial siderophores. TYPLEX has been trialled as a feed additive in farming of commercial broilers, reducing Campylobacter loads by 2-3 log and leading to faster growth and better feed consumption. These ferric chelates offer a good alternative feed additive to antibiotics helping to reduce the indiscriminate use of preventative antibiotics in broiler farming to control Campylobacter infections.

Speech planning and execution in children who stutter: Preliminary findings from a fNIRS investigation.

Few studies have investigated the neural mechanisms underlying speech production in children who stutter (CWS), despite the critical importance of understanding these mechanisms closer to the time of stuttering onset. The relative contributions of speech planning and execution in CWS therefore are also unknown. Using functional near-infrared spectroscopy, the current study investigated neural mechanisms of planning and execution in a small sample of 9-12 year-old CWS and controls (N = 12) by implementing two tasks that manipulated speech planning and execution loads.

Biocatalytic access to betazole using a one-pot multienzymatic system in continuous flow.

As an alternative to classical synthetic approaches for the production of betazole drug, a one-pot biocatalytic system for this pharmaceutical molecule from its alcohol precursor has been developed. An ω-transaminase, an alcohol dehydrogenase and a water-forming NADH oxidase for cofactor recycling have been combined to catalyse this reaction, yielding 75% molar conversion in batch reactions with soluble enzymes. This multienzyme system was then co-immobilised through a newly established protocol for sequential functionalization of a methacrylate-based porous carrier to enable tailored immobilisation chemistries for each enzyme.

Increased tissue stiffness triggers contractile dysfunction and telomere shortening in dystrophic cardiomyocytes.

Duchenne muscular dystrophy (DMD) is a rare X-linked recessive disease that is associated with severe progressive muscle degeneration culminating in death due to cardiorespiratory failure. We previously observed an unexpected proliferation-independent telomere shortening in cardiomyocytes of a DMD mouse model. Here, we provide mechanistic insights using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).

Internet 'shellebrity' reflects on origin of rare mirror-image snails.

While animal bodies are typically bilaterally symmetric on the outside, the internal organs nearly always show an invariant left-right (LR) asymmetry. In comparison, snails are both internally and externally LR asymmetric, outwardly obvious in the shell coiling direction, or chirality. Although some species of snail are naturally variable for chirality, sinistral individuals occur very rarely in most species.

Antimicrobial resistance: the good, the bad, and the ugly.

As the Royal Society for Biology (RSB) was forming 10 years ago, antimicrobial resistance (AMR) was being heralded as the next threat with a magnitude on a par with global warming. Just a few years later, in 2016, Jim O'Neill's report was published laying out recommendations for tackling drug-resistant infections globally. Where are we now, and what are the challenges ahead? As a slow burner, how will the impact of AMR compare against the recent rapid devastation of the COVID-19 pandemic, and how can we channel some of the good things that come from it (like the awareness and technique of effective hand hygiene) to help us combat AMR speedily and definitively?

Monitoring the Formation and Reactivity of Organometallic Alkane and Fluoroalkane Complexes with Silanes and Xe Using Time-Resolved X-ray Absorption Fine Structure Spectroscopy.

Complexes with weakly coordinating ligands are often formed in chemical reactions and can play key roles in determining the reactivity, particularly in catalytic reactions. Using time-resolved X-ray absorption fine structure (XAFS) spectroscopy in combination with time-resolved IR (TRIR) spectroscopy and tungsten hexacarbonyl, W(CO), we are able to structurally characterize the formation of an organometallic alkane complex, determine the W-C distances, and monitor the reactivity with silane to form an organometallic silane complex. Experiments in perfluorosolvents doped with xenon afford initially the corresponding solvated complex, which is sufficiently reactive in the presence of Xe that we can then observe the coordination of Xe to the metal center, providing a unique insight into the metal-xenon bonding.

Phonon Spectroscopy with Chirped Shear and Compressive Acoustic Pulses.

Picosecond duration compressive and shear phonon wave packets injected into (311) GaAs slabs transform after propagation through ∼1  mm into chirped acoustic pulses with a frequency increasing in time due to phonon dispersion. By probing the temporal optical response to coherent phonons in a near surface layer of the GaAs slab, we show that phonon chirping opens a transformational route for high-sensitivity terahertz and subterahertz phonon spectroscopy. Temporal gating of the chirped phonon pulse allows the selection of a narrow band phonon spectrum with a central frequency up to 0.

Probing the Carbon-Hydrogen Activation of Alkanes Following Photolysis of Tp'Rh(CNR)(carbodiimide): A Computational and Time-Resolved Infrared Spectroscopic Study.

Carbon-hydrogen bond activation of alkanes by Tp'Rh(CNR) (Tp' = Tp = trispyrazolylborate or Tp* = tris(3,5-dimethylpyrazolyl)borate) were followed by time-resolved infrared spectroscopy (TRIR) in the υ(CNR) and υ(B-H) spectral regions on Tp*Rh(CNCHCMe), and their reaction mechanisms were modeled by density functional theory (DFT) on TpRh(CNMe). The major intermediate species were: κ-η-alkane complex (1); κ-η-alkane complex (2); and κ-alkyl hydride (3). Calculations predict that the barrier between 1 and 2 arises from a triplet-singlet crossing and intermediate 2 proceeds over the rate-determining C-H activation barrier to give the final product 3.

Waterjet and laser etching: the nonlinear inverse problem.

In waterjet and laser milling, material is removed from a solid surface in a succession of layers to create a new shape, in a depth-controlled manner. The inverse problem consists of defining the control parameters, in particular, the two-dimensional beam path, to arrive at a prescribed freeform surface. Waterjet milling (WJM) and pulsed laser ablation (PLA) are studied in this paper, since a generic nonlinear material removal model is appropriate for both of these processes.

An imaging photoelectron-photoion coincidence investigation of homochiral 2R,3R-butanediol clusters.

We report an experimental investigation of homochiral cluster formation in seeded molecular beam expansions of (2R,3R)-butanediol. Synchrotron radiation vacuum ultraviolet photoionization measurements have been performed using a double imaging electron-ion spectrometer in various configurations and modes of operation. These include measurements of the cluster ion mass spectra, wavelength scanned ion yields, and threshold electron spectra.

The Role of Unconventional Hydrogen Bonds in Determining BII Propensities in B-DNA.

An accurate understanding of DNA backbone transitions is likely to be the key for elucidating the puzzle of the intricate sequence-dependent mechanical properties that govern most of the biologically relevant functions of the double helix. One factor believed to be important in indirect recognition within protein-DNA complexes is the combined effect of two DNA backbone torsions (ε and ζ) which give rise to the well-known BI/BII conformational equilibrium. In this work we explain the sequence-dependent BII propensity observed in RpY steps (R = purine; Y = pyrimidine) at the tetranucleotide level with the help of a previously undetected C-H···O contact between atoms belonging to adjacent bases.

Reverse energy partitioning-An efficient algorithm for computing the density of states, partition functions, and free energy of solids.

A robust and model free Monte Carlo simulation method is proposed to address the challenge in computing the classical density of states and partition function of solids. Starting from the minimum configurational energy, the algorithm partitions the entire energy range in the increasing energy direction ("upward") into subdivisions whose integrated density of states is known. When combined with the density of states computed from the "downward" energy partitioning approach [H.

Milliseconds Make the Difference in the Far-from-Equilibrium Self-Assembly of Supramolecular Chiral Nanostructures.

The effect of diffusion-controlled microfluidic conditions in the very initial stages of a far-from-equilibrium self-assembly process on the evolution of aggregate chirality in a multicomponent supramolecular system is shown.

White matter tract and glial-associated changes in 5-hydroxymethylcytosine following chronic cerebral hypoperfusion.

White matter abnormalities due to age-related cerebrovascular alterations is a common pathological hallmark associated with functional impairment in the elderly which has been modeled in chronically hypoperfused mice. 5-Methylcytosine (5mC) and its oxidized derivative 5-hydroxymethylcytosine (5hmC) are DNA modifications that have been recently linked with age-related neurodegeneration and cerebrovascular pathology. Here we conducted a pilot investigation of whether chronic cerebral hypoperfusion might affect genomic distribution of these modifications and/ or a Ten-Eleven Translocation protein 2 (TET2) which catalyses hydroxymethylation in white and grey matter regions of this animal model.

The association of physiological cortisol and IVF treatment outcomes: a systematic review.

Purpose: A systematic review was conducted to (1) collate and synthesise the available evidence for the role of cortisol in relation to IVF treatment outcomes; (2) to establish the strength of an association between cortisol and IVF; and (3) to assess the overall quality of the studies and guide future research in this area.

Methods: Seven electronic databases, including the reference lists of published papers, were searched. Inclusion criteria qualified any prospective/observational cohort study that reported original data.

Probing affinity and ubiquitin linkage selectivity of ubiquitin-binding domains using mass spectrometry.

Non-covalent interactions between ubiquitin (Ub)-modified substrates and Ub-binding domains (UBDs) are fundamental to signal transduction by Ub receptor proteins. Poly-Ub chains, linked through isopeptide bonds between internal Lys residues and the C-terminus of Ub, can be assembled with varied topologies to mediate different cellular processes. We have developed and applied a rapid and sensitive electrospray ionization-mass spectrometry (ESI-MS) method to determine isopeptide linkage-selectivity and affinity of poly-Ub·UBD interactions.

Understanding the factors affecting the activation of alkane by Cp'Rh(CO)2 (Cp' = Cp or Cp*).

Fast time-resolved infrared spectroscopic measurements have allowed precise determination of the rates of activation of alkanes by Cp'Rh(CO) (Cp(') = η(5)-C(5)H(5) or η(5)-C(5)Me(5)). We have monitored the kinetics of C─H activation in solution at room temperature and determined how the change in rate of oxidative cleavage varies from methane to decane. The lifetime of CpRh(CO)(alkane) shows a nearly linear behavior with respect to the length of the alkane chain, whereas the related Cp*Rh(CO)(alkane) has clear oscillatory behavior upon changing the alkane.

Is the direction of second-order, contrast-defined motion patterns visible to standard motion-energy detectors: a model answer?

Previous psychophysical studies (e.g., Smith & Ledgeway, 1997) have provided evidence that under some conditions, the detection of a particular class of stimuli (contrast-modulated static noise) widely employed to study second-order motion processing may be inadvertently based on encoding local imbalances in luminance motion energy.

Five-year-old children's difficulty with false belief when the sought entity is a person.

A total of 153 children (excluding those who erred on control questions), mainly 5 and 7 years of age, participated in two experiments that involved tests of false belief. In the task, the sought entity was first at Location 1 and then, unknown to the searching protagonist, it moved to Location 2. In Experiment 1, performance was well below ceiling in 5-year-olds when the sought entity was a person, and this contrasted with a task in which the sought entity was a physical object.

Spatial frequency selective masking of first-order and second-order motion in the absence of off-frequency 'looking'.

Converging evidence suggests that, at least initially, first-order (luminance defined) and second-order (e.g. contrast defined) motion are processed independently in human vision.

Chasing the genes that control resistance to gastrointestinal nematodes.

The host-protective immune response to infection with gastrointestinal (GI) nematodes involves a range of interacting processes that begin with recognition of the parasite's antigens and culminate in an inflammatory reaction in the intestinal mucosa. Precisely which immune effectors are responsible for the loss of specific worms is still not known although many candidate effectors have been proposed. However, it is now clear that many different genes regulate the response and that differences between hosts (fast or strong versus slow or weak responses) can be explained by allelic variation in crucial genes associated with the gene cascade that accompanies the immune response and/or genes encoding constitutively expressed receptor/signalling molecules.