Interface (United Kingdom)

Every year, cancer is responsible for millions of deaths worldwide and, even though much progress has been achieved in medicine, there are still many issues that must be addressed in order to improve cancer therapy. For this reason, oncological research is putting a lot of effort towards finding new and efficient therapies which can alleviate critical side effects caused by conventional treatments. Different technologies are currently under evaluation in clinical trials or have been already introduced into clinical practice. While nanomedicine is contributing to the development of biocompatible materials both for diagnostic and therapeutic purposes, bioengineering of extracellular vesicles and cells derived from patients has allowed designing ad hoc systems and univocal targeting strategies. In this review, we will provide an in-depth analysis of the most innovative advances in basic and applied cancer research.

Research into alternative renewable energy generation is a priority, due to the ever-increasing concern of climate change. Microbial fuel cells (MFCs) are one potential avenue to be explored, as a partial solution towards combating the over-reliance on fossil fuel based electricity. Limitations have slowed the advancement of MFC development, including low power generation, expensive electrode materials and the inability to scale up MFCs to industrially relevant capacities. However, utilisation of new advanced electrode-materials (i.e. 2D nanomaterials), has promise to advance the field of electromicrobiology. New electrode materials coupled with a more thorough understanding of the mechanisms in which electrogenic bacteria partake in electron transfer could dramatically increase power outputs, potentially reaching the upper extremities of theoretical limits. Continued research into both the electrochemistry and microbiology is of paramount importance in order to achieve industrial-scale development of MFCs. This review gives an overview of the current field and knowledge in regards to MFCs and discusses the known mechanisms underpinning MFC technology, which allows bacteria to facilitate in electron transfer processes. This review focusses specifically on enhancing the performance of MFCs, with the key intrinsic factor currently limiting power output from MFCs being the rate of electron transfer to/from the anode; the use of advanced carbon-based materials as electrode surfaces is discussed.

Complex three-dimensional biophotonic nanostructures produce the vivid structural colors of many butterfly wing scales, but their exact nanoscale organization is uncertain. We used small angle X-ray scattering (SAXS) on single scales to characterize the 3D photonic nanostructures of five butterfly species from two families (Papilionidae, Lycaenidae). We identify these chitin and air nanostructures as single network gyroid (I4(1)32) photonic crystals. We describe their optical function from SAXS data and photonic band-gap modeling. Butterflies apparently grow these gyroid nanostructures by exploiting the self-organizing physical dynamics of biological lipid-bilayer membranes. These butterfly photonic nanostructures initially develop within scale cells as a core-shell double gyroid (Ia3d), as seen in block-copolymer systems, with a pentacontinuous volume comprised of extracellular space, cell plasma membrane, cellular cytoplasm, smooth endoplasmic reticulum (SER) membrane, and intra-SER lumen. This double gyroid nanostructure is subsequently transformed into a single gyroid network through the deposition of chitin in the extracellular space and the degeneration of the rest of the cell. The butterflies develop the thermodynamically favored double gyroid precursors as a route to the optically more efficient single gyroid nanostructures. Current approaches to photonic crystal engineering also aim to produce single gyroid motifs. The biologically derived photonic nanostructures characterized here may offer a convenient template for producing optical devices based on biomimicry or direct dielectric infiltration.

Stabilization of aqueous suspensions of graphene single sheets by single-stranded DNA is demonstrated using a range of physical methods. The negatively charged bio-functionalized graphene sheets are spontaneously assembled into layered hybrid nanocomposites containing intercalated DNA molecules, or co-intercalated mixtures of DNA and the redox protein, cytochrome c. Small-molecule reducing agents readily access the intercalated proteins.

We introduce an extended version of oxDNA, a coarse-grained model of deoxyribonucleic acid (DNA) designed to capture the thermodynamic, structural, and mechanical properties of single- and double-stranded DNA. By including explicit major and minor grooves and by slightly modifying the coaxial stacking and backbone-backbone interactions, we improve the ability of the model to treat large (kilobase-pair) structures, such as DNA origami, which are sensitive to these geometric features. Further, we extend the model, which was previously parameterised to just one salt concentration ([Na+] = 0.5M), so that it can be used for a range of salt concentrations including those corresponding to physiological conditions. Finally, we use new experimental data to parameterise the oxDNA potential so that consecutive adenine bases stack with a different strength to consecutive thymine bases, a feature which allows a more accurate treatment of systems where the flexibility of single-stranded regions is important. We illustrate the new possibilities opened up by the updated model, oxDNA2, by presenting results from simulations of the structure of large DNA objects and by using the model to investigate some salt-dependent properties of DNA.

Current density-voltage characteristics are presented for a molecular structure of the form metal/organic-multilayer/metal for which the rectifierlike forward bias current density dependence is unequivocally associated with zwitterionic molecules. By placing passive organic barriers between the metal layers and the active molecules we prove that Schottky barrier effects are not important. This is the clearest evidence so far for molecularly controlled rectification, the basis for molecular electronics.

A detailed analysis of the surface modes of a thin slab of material of dielectric constant ${\mathrm{\ensuremath{\epsilon}}}_{2}$ (=${\mathrm{\ensuremath{\epsilon}}}_{\mathit{r}2}$-i${\mathrm{\ensuremath{\epsilon}}}_{\mathit{i}2}$) surrounded symmetrically by dielectric media is presented. Results show that in the thin-film limit, as well as the well-known long-range surface plasmon for a thin metal layer and the TM guided mode for a thin dielectric, a long-range surface mode exists for almost any value of ${\mathrm{\ensuremath{\epsilon}}}_{2}$. This is even true if the imaginary part of ${\mathrm{\ensuremath{\epsilon}}}_{2}$, ${\mathrm{\ensuremath{\epsilon}}}_{\mathit{i}2}$, is much larger than the real part ${\mathrm{\ensuremath{\epsilon}}}_{\mathit{r}2}$. We also find that a long-range surface mode may arise from the coupling between two surfaces which individually cannot support a surface mode. These are a pair of special coupled-surface modes which may exist below a certain critical film thickness and which have two separate propagation vectors each with the same field symmetry. It is also found that the inverse situation may pertain, that is for certain relative values of dielectric constants even though ordinary surface modes may exist, below a critical thickness the resulting coupled long-range mode no longer exists. The analysis has also been extended to practical situations with weakly absorbing surrounding media and to circumstances where the dielectric constants of the surrounding media are slightly different. Both of these effects modify the dispersion relations obtained for the simple case and introduce further limit thicknesses into the problem. Analytic formulas in the thin-film limit are presented for all the above situations and field distributions and energy flow (Poynting vector) profiles presented to illustrate as necessary the nature of the modes supported by these systems. Finally experimental results are presented which illustrate the rather sweeping conclusion that a long-range surface mode may exist on a thin film for almost all values of ${\mathrm{\ensuremath{\epsilon}}}_{\mathit{r}2}$ and ${\mathrm{\ensuremath{\epsilon}}}_{\mathit{i}2}$. This result paves the way for a range of optics experiments on absorbing structures.

Darkening of parts of the Greenland ice sheet surface during the summer months leads to reduced albedo and increased melting. Here we show that heavily pigmented, actively photosynthesising microalgae and cyanobacteria are present on the bare ice. We demonstrate the widespread abundance of green algae in the Zygnematophyceae on the ice sheet surface in Southwest Greenland. Photophysiological measurements (variable chlorophyll fluorescence) indicate that the ice algae likely use screening mechanisms to downregulate photosynthesis when exposed to high intensities of visible and ultraviolet radiation, rather than non-photochemical quenching or cell movement. Using imaging microspectrophotometry, we demonstrate that intact cells and filaments absorb light with characteristic spectral profiles across ultraviolet and visible wavelengths, whereas inorganic dust particles typical for these areas display little absorption. Our results indicate that the phototrophic community growing directly on the bare ice, through their photophysiology, most likely have an important role in changing albedo, and subsequently may impact melt rates on the ice sheet.

High-resolution core- and valence-level photoemission spectra of Nb-doped ${\mathrm{TiO}}_{2}$ ceramics $({\mathrm{Ti}}_{1\ensuremath{-}x}{\mathrm{Nb}}_{x}{\mathrm{O}}_{2}$ with $0.01<x<0.8)$ have been measured using monochromatic x-ray excitation. Nb doping produces a well-defined photoemission peak in the bulk band gap of rutile, whose intensity increases with increasing doping level. Core-level spectroscopy shows that the Nb is incorporated within the rutile lattice at low doping levels mainly as Nb(V) and that the gap state is associated with Ti(III) ions. This conclusion is reinforced by variable energy photoemission measurements on ${\mathrm{Ti}}_{0.9}{\mathrm{Nb}}_{0.1}{\mathrm{O}}_{2}$ in the vicinity of the Ti $3p$ and Nb $4p$ core thresholds. The photoemission resonance profile for the gap states reaches half maximum intensity at the same energy as found for oxygen-deficient ${\mathrm{TiO}}_{2\ensuremath{-}x}$ but is shifted from the resonance profile for the Nb $4d$ states of ${\mathrm{NbO}}_{2}.$ STM images on Nb-doped ${\mathrm{TiO}}_{2}(110)$ are considered in relation to the spectroscopic measurements. Nb dopant atoms are imaged as ``bright spot'' clusters, implying delocalization of charge from Nb onto neighboring Ti ions. The experimental x-ray photoelectron spectroscopy data are compared with density-of-states profiles derived from local-density approximation calculations on pure and Nb-doped ${\mathrm{TiO}}_{2}$ clusters. These calculations show that Nb doping of ${\mathrm{TiO}}_{2}$ introduces new states of mixed $\mathrm{Nb}4d--\mathrm{Ti}3d$ character above the O $2p$ valence band of the host material. In addition, there is increased x-ray photoemission intensity across the O $2p$ valence band owing to strong $\mathrm{Nb}4d/\mathrm{O}2p$ hybridization and a cross section for ionization of Nb $4d$ states that is an order of magnitude larger than that for O $2p$ or Ti $3d$ states.

has significantly increased. Besides traditional approaches, the synthesis, shaping, structural patterning, and postprocessing chemical functionalization of the materials surface is inspired by strategies which mimic processes in nature. Would such materials deliver new technologies? Answering this question requires the merging of historical knowledge and current research from different fields of science. Practically, we need an effective defragmentation of the research area. From our perspective, the superficial accounting of material properties, chemistry of the surfaces, and the behavior of biomolecules next to such surfaces is a problem. This is particularly of concern when we wish to bridge between technologies in vitro and biotechnologies in vivo. Further, besides the potential practical technological efficiency and advantages such materials might exhibit, we have to consider the wider long-term implications of material stability and toxicity. In this contribution, we present a critical review of recent advances in the chemistry and engineering of MO-based biocomposites, highlighting the role of interactions at the interface and the techniques by which these can be studied. At the end of the article, we outline the challenges which hamper progress in research and extrapolate to developing and promising directions including additive manufacturing and synthetic biology that could benefit from molecular level understanding of interactions occurring between inanimate (abiotic) and living (biotic) materials.

Contact of Mycobacterium tuberculosis (M.tb) with the immune system requires interactions between microbial surface molecules and host pattern recognition receptors. Major M.tb-exposed cell envelope molecules, such as lipomannan (LM), contain subtle structural variations that affect the nature of the immune response. Here we show that LM from virulent M.tb (TB-LM), but not from avirulent Myocobacterium smegmatis (SmegLM), is a potent inhibitor of TNF biosynthesis in human macrophages. This difference in response is not because of variation in Toll-like receptor 2-dependent activation of the signaling kinase MAPK p38. Rather, TB-LM stimulation leads to destabilization of TNF mRNA transcripts and subsequent failure to produce TNF protein. In contrast, SmegLM enhances MAPK-activated protein kinase 2 phosphorylation, which is critical for maintaining TNF mRNA stability in part by contributing microRNAs (miRNAs). In this context, human miRNA miR-125b binds to the 3' UTR region of TNF mRNA and destabilizes the transcript, whereas miR-155 enhances TNF production by increasing TNF mRNA half-life and limiting expression of SHIP1, a negative regulator of the PI3K/Akt pathway. We show that macrophages incubated with TB-LM and live M.tb induce high miR-125b expression and low miR-155 expression with correspondingly low TNF production. In contrast, SmegLM and live M. smegmatis induce high miR-155 expression and low miR-125b expression with high TNF production. Thus, we identify a unique cellular mechanism underlying the ability of a major M.tb cell wall component, TB-LM, to block TNF biosynthesis in human macrophages, thereby allowing M.tb to subvert host immunity and potentially increase its virulence.

In this work, we synthesized N, F, P ternary doped macroporous carbon fibers (NFPC) for the first time and it exhibits efficient electrocatalytic activity as a bifunctional catalyst for ORR, OER and Zn-air batteries.

BACKGROUND: Socioeconomic inequalities in alcohol-related mortality have been documented in several European countries, but it is unknown whether the magnitude of these inequalities differs between countries and whether these inequalities increase or decrease over time. METHODS AND FINDINGS: We collected and harmonized data on mortality from four alcohol-related causes (alcoholic psychosis, dependence, and abuse; alcoholic cardiomyopathy; alcoholic liver cirrhosis; and accidental poisoning by alcohol) by age, sex, education level, and occupational class in 20 European populations from 17 different countries, both for a recent period and for previous points in time, using data from mortality registers. Mortality was age-standardized using the European Standard Population, and measures for both relative and absolute inequality between low and high socioeconomic groups (as measured by educational level and occupational class) were calculated. Rates of alcohol-related mortality are higher in lower educational and occupational groups in all countries. Both relative and absolute inequalities are largest in Eastern Europe, and Finland and Denmark also have very large absolute inequalities in alcohol-related mortality. For example, for educational inequality among Finnish men, the relative index of inequality is 3.6 (95% CI 3.3-4.0) and the slope index of inequality is 112.5 (95% CI 106.2-118.8) deaths per 100,000 person-years. Over time, the relative inequality in alcohol-related mortality has increased in many countries, but the main change is a strong rise of absolute inequality in several countries in Eastern Europe (Hungary, Lithuania, Estonia) and Northern Europe (Finland, Denmark) because of a rapid rise in alcohol-related mortality in lower socioeconomic groups. In some of these countries, alcohol-related causes now account for 10% or more of the socioeconomic inequality in total mortality. Because our study relies on routinely collected underlying causes of death, it is likely that our results underestimate the true extent of the problem. CONCLUSIONS: Alcohol-related conditions play an important role in generating inequalities in total mortality in many European countries. Countering increases in alcohol-related mortality in lower socioeconomic groups is essential for reducing inequalities in mortality. Studies of why such increases have not occurred in countries like France, Switzerland, Spain, and Italy can help in developing evidence-based policies in other European countries.

We describe the evolution of the novel shared drawing medium ClearBoard which was designed to seamlessly integrate an interpersonal space and a shared workspace. ClearBoard permits coworkers in two locations to draw with color markers or with electronic pens and software tools while maintaining direct eye contact and the ability to employ natural gestures. The ClearBoard design is based on the key metaphor of “talking through and drawing on a transparent glass window.” We describe the evolution from ClearBoard-1 (which enables shared video drawing) to ClearBoard-2 (which incorporates TeamPaint, a multiuser paint editor). Initial observations and findings gained through the experimental use of the prototype, including the feature of “gaze awareness,” are discussed. Further experiments are conducted with ClearBoard-0 (a simple mockup), ClearBoard-1, and an actual desktop as a control. In the settings we examined, the ClearBoard environment led to more eye contact and potential awareness of collaborator's gaze direction over the traditional desktop environment.

In the world of crystal engineering in which the focus of effort is on the assembly of molecular species by crystallisation, surprisingly little attention has been paid to the actual nucleation and crystallisation processes involved. This Highlight explores the structural aspects of the nucleation process in a range of small molecule systems. It uses a combination of thermodynamic, structural and modelling approaches in order to progress our understanding of the link between liquid phase molecular assemblies, which constitute crystal growth units, and their solid state counterparts, the supramolecular synthons.

Hierarchically porous materials are an ideal material platform for constructing high performance Li-ion batteries (LIBs), offering great advantages such as large contact area between the electrode and the electrolyte, fast and flexible transport pathways for the electrolyte ions and the space for buffering the strain caused by repeated Li insertion/extraction. In this work, NiO microspheres with hierarchically porous structures have been synthesized via a facile thermal decomposition method by only using a simple precursor. The superstructures are composed of nanocrystals with high specific surface area, large pore volume, and broad pore size distribution. The electrochemical properties of 3D hierarchical mesoporous NiO microspheres were examined by cyclic voltammetry and galvanostatic charge-discharge studies. The results demonstrate that the as-prepared NiO nanospheres are excellent electrode materials in LIBs with high specific capacity, good retention and rate performance. The 3D hierarchical mesoporous NiO microspheres can retain a reversible capacity of 800.2 mA h g(-1) after 100 cycles at a high current density of 500 mA g(-1).

Nonpolar phase synthesized hydrophobic nanocrystals show attractive properties and have demonstrated prominent potential in biomedical applications. However, the preparation of biocompatible nanocrystals is made difficult by the presence of hydrophobic surfactant stabilizer on their surfaces. To address this limitation, we have developed a facile, high efficiency, single-phase and low-cost method to convert hydrophobic magnetic nanoparticles (MNPs) to an aqueous phase using tetrahydrofuran, NaOH and 3,4-dihydroxyhydrocinnamic acid without any complicated organic synthesis. The as-transferred hydrophilic MNPs are water-soluble over a wide pH range (pH = 3-12), and the solubility is pH-controllable. Furthermore, the as-transferred MNPs with carboxylate can be readily adapted with further surface functionalization, varying from small molecule dyes to oligonucleotides and enzymes. Finally, the strategy developed here can easily be extended to other types of hydrophobic nanoparticles to facilitate biomedical applications of nanomaterials.

Molecular analysis of grassland rhizosphere soil has demonstrated complex and diverse bacterial communities, with resultant difficulties in detecting links between plant and bacterial communities. These studies have, however, analyzed "bulk" rhizosphere soil, rather than rhizoplane communities, which interact most closely with plants through utilization of root exudates. The aim of this study was to test the hypothesis that plant species was a major driver for bacterial rhizoplane community composition on individual plant roots. DNA extracted from individual roots was used to determine plant identity, by analysis of the plastid tRNA leucine (trnL) UAA gene intron, and plant-related bacterial communities. Bacterial communities were characterized by analysis of PCR-amplified 16S rRNA genes using two fingerprinting methods: terminal restriction fragment length polymorphisms (T-RFLP) and denaturing gradient gel electrophoresis (DGGE). Links between plant and bacterial rhizoplane communities could not be detected by visual examination of T-RFLP patterns or DGGE banding profiles. Statistical analysis of fingerprint patterns did not reveal a relationship between bacterial community composition and plant species but did demonstrate an influence of plant community composition. The data also indicated that topography and other, uncharacterized, environmental factors are important in driving bacterial community composition in grassland soils. T-RFLP had greater potential resolving power than DGGE, but findings from the two methods were not significantly different.

The addition of Triton X-100 slows down the crystallization rate of TS-1, while the rota-crystallization accelerates the incorporation rate of Ti.

A new modeling system to determine the optical response function of a multilayer structure with imposed periodicity in the plane of the layers, a multilayer diffraction grating, is described. This new model has two essential ingredients. This model is based on the well-established coordinate transformation procedure developed by Chandezon et al. [ J. Opt. Soc. Am.72, 839– 846 ( 1982)] in which a periodically modulated surface is transformed into a frame in which it is flat, permitting simpler use of Maxwell’s boundary conditions. Then, instead of using the conventional transfer-matrix method, we developed a scattering-matrix technique that permits the modeling of very thick (of the order of 1 μm or greater) multilayer systems with many field components without numerical instability. Model programs have been developed based on this new scattering-matrix approach and tested by comparison with other models and experimental data.