materials science

Electromagnetic radiation is energy that interacts with matter. The interaction process is of great importance to the sensing applications that characterize material media. Parameters like constant dielectric represent matter characteristics and they are identified using emission, interaction and reception of electromagnetic radiation in adapted environmental conditions. How the electromagnetic wave responds when it interacts with the material media depends on the range of frequency used and the medium parameters...

Since the embryonic stem cells have knocked the doorsteps, they have proved themselves in the field of science, research, and medicines, but the hovered restrictions confine their application in human welfare. Alternate approaches used to reprogram the cells to the pluripotent state were not up to par, but the innovation of induced pluripotent stem cells (iPSCs) paved a new hope for the researchers. Soon after the discovery, iPSCs technology is undergoing renaissance day by day, i.e., from the use of genetic material to recombinant proteins and now only chemicals are employed to convert somatic cells to iPSCs...

Several researchers recently outlined unacknowledged costs of open science practices, arguing these costs may outweigh benefits and stifle discovery of novel findings. We scrutinize these researchers' (a) statistical concern that heightened stringency with respect to false-positives will increase false-negatives and (b) metascientific concern that larger samples and executing direct replications engender opportunity costs that will decrease the rate of making novel discoveries. We argue their statistical concern is unwarranted given open science proponents recommend such practices to reduce the inflated Type I error rate from ...

Hundreds of positions for psychologists were established after the National Socialists seized power in 1933. It has accordingly been asserted that professional psychology in Germany experienced significant growth during the National Socialist period. An analysis of archival materials and of a recent collection of biographies indicates otherwise, however. German psychology, in fact, declined because of systematic persecution and a surge of emigration, a deficit that subsequent cohorts were barely able to make up until 1945...

The confinement of noble gases on nanostructured surfaces, in contrast to bulk materials, at non-cryogenic temperatures represents a formidable challenge. In this work, individual Ar atoms are trapped at 300 K in nano-cages consisting of (alumino)silicate hexagonal prisms forming a two-dimensional array on a planar surface. The trapping of Ar atoms is detected in situ using synchrotron-based ambient pressure X-ray photoelectron spectroscopy. The atoms remain in the cages upon heating to 400 K. The trapping and release of Ar is studied combining surface science methods and density functional theory calculations...

We present a review of the use of selected nanofabricated thin films to deliver a host of capabilities and insights spanning bioanalytical and biophysical chemistry, materials science, and fundamental molecular-level research. We discuss approaches where thin films have been vital, enabling experimental studies using a variety of optical spectroscopies across the visible and infrared spectral range, electron microscopies, and related techniques such as electron energy loss spectroscopy, X-ray photoelectron spectroscopy, and single molecule sensing...

Functional nanoscale structures consisting of a DNA molecule coupled to graphene or graphene oxide (GO) have great potential for applications in biosensors, biomedicine, nanotechnology, and materials science. Extensive studies using the most sophisticated experimental techniques and theoretical methods have still not clarified the dynamic process of single-stranded DNA (ssDNA) adsorbed on a GO surface. Based on a molecular dynamics simulation, this work shows that an ssDNA segment could be stably adsorbed on a GO surface through hydrogen bonding and a π-π stacking interaction, with preferential binding to an oxidized region rather than to an unoxidized region of the GO surface...

First administered in November 1963, the orthopedic in-training examination (OITE) is now distributed to more than 4000 residents in over 20 countries and has become important for evaluation of resident fund of knowledge. Several studies have assessed the effect of didactic programs on resident performance, but only recently has it become possible to assess detailed testtaking metrics such as time spent per question. Here, we report the first assessment of resident OITE performance utilizing this full electronic dataset from two large academic institutions...

Thermal annealing strongly impacts the nano- and microstructure of conjugated polymers. Despite the fundamental importance for the resulting optoelectronic behavior of this class of materials, the underlying crystallization processes have not received the same attention that is encountered in other disciplines of materials science. The question arises whether classical treatment of nucleation and growth phenomena is truly applicable to conjugated polymers? Here, the isothermal crystallization behavior of the conjugated polymer poly(3-(2'-ethyl)hexylthiophene) (P3EHT) is monitored with differential scanning calorimetry (DSC)...

The host immune system (T-lymphocytes and their pro-inflammatory cytokines) has been shown to compromise bone regeneration ability of mesenchymal stem cells (MSCs). We have recently shown that hydrogel, used as an encapsulating biomaterial affects the cross-talk among host immune cells and MSCs. However, the role of hydrogel elasticity and porosity in regulation of cross-talk between dental-derived MSCs and immune cells is unclear. In this study, we demonstrate that the modulus of elasticity and porosity of the scaffold influence T-lymphocyte-dental MSC interplay by regulating the penetration of inflammatory T cells and their cytokines...

The official school regulator in England (OFSTED) recently reported that the delivery of science lessons has been significantly diminished in many primary schools. There is concern that the lack of good quality science in school can reduce the recruitment of young scientists, and the level of science literacy among the general public. We believe university scientists and undergraduate students can have a significant impact in the delivery of science in primary schools. However, a relatively small proportion of scientists engage with young children to improve curricular primary school science education...

Lanthanide-doped photon-upconversion nanoparticles (UCNPs) have been the focus of many research activities in materials and life sciences in the last 15 years because of their potential to convert light between different spectral regions and their unique photophysical properties. To fully exploit the application potential of these fascinating nanomaterials, a number of challenges have to be overcome, such as the low brightness, particularly of small UCNPs, and the reliable quantification of the excitation-power-density-dependent upconversion luminescence...

Chemical sensing is one of the most important applications of nanoscience, whose ultimate aim is to seek higher sensitivity. In recent years, graphene with intriguing quantum properties has spurred dramatic advances ranging from materials science to optoelectronics and mechanics, showing its potential to realize individual molecule solid-state sensors. However, for optical sensing, the single atom thickness of graphene greatly limits the light-graphene interaction, bottlenecking their performances. Here we demonstrate a novel approach based on the forward phase-matched Brillouin optomechanics in a graphene inner-deposited high Q (> 2×106) microfluidic resonator, expanding the 'electron-photon' interaction in conventional graphene optical devices to the 'electron-phonon-photon' process...

Lignin is a natural, renewable biopolymer synthesized by plants. It is a macromolecule consisting of aromatic structures with high density of functional groups making it an ideal precursor for the design of sustainable biomaterials for applications such as drug delivery. The rational design of these materials requires an in-depth understanding of the underlying lignin self-assembly in solution. Colloidal transformations from nano-sized lignin assemblies to sub-micron sized spherical particles upon solvent exchange were studied using small angle X-ray scattering, dynamic light scattering and electron microscopy...

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We consider wall-to-wall transport of a passive tracer by divergence-free velocity vector fields u. Given an enstrophy budget ⟨|∇u|^{2}⟩≤Pe^{2} we construct steady two-dimensional flows that transport at rates Nu(u)≳Pe^{2/3}/(logPe)^{4/3} in the large enstrophy limit. Combined with the known upper bound Nu(u)≲Pe^{2/3} for any such enstrophy-constrained flow, we conclude that maximally transporting flows satisfy Nu∼Pe^{2/3} up to possible logarithmic corrections. Combined with known transport bounds in the context of Rayleigh-Bénard convection, this establishes that while suitable flows approaching the "ultimate" heat transport scaling Nu∼Ra^{1/2} exist, they are not always realizable as buoyancy-driven flows...

This essay considers some of the major theological differences between Eastern and Western traditions of Christianity and puts forward proposals about how these might be related to the divergent trajectories of the formal study of nature in these two cultural contexts. A key difference lies in the “other-worldly” orientation of Eastern Orthodoxy and its emphasis on deification, which contrast sharply with ideas of original sin and fall–redemption theology in the West. These latter ideas came to play a significant role in the rise of Western science, with the sciences being understood as part of a practical redemptive exercise that could help alleviate the material consequences of original sin...

This essay offers an overview of the history of the relations between science and Eastern Christianity based on Greek-language sources. The civilizations concerned are the Byzantine Empire, the Christian Orthodox communities of the Ottoman Empire, and modern Greece, as a case study of a national state. Beginning with the Greek Church Fathers, the essay investigates the ideas of theologians and scholars on nature. Neoplatonism, the theological debates of Iconoclasm and Hesychasm, the proposed union of the Eastern and Western Churches, and the complex relations with the Hellenic past all had notable impacts on the conception of science held by the Byzantine Orthodox...

At the turn of the nineteenth century, at its headquarters in the City of London, the Honourable East India Company established a new museum and library. By midcentury this museum would contain one of Europe’s most extensive collections of the natural history, arts, and sciences of Asia. This essay uses the early history of the company’s museum, focusing in particular on its natural history collections, to explore the material relationship between scientific practice and the imperial political economy. Much of the collections had been gathered in the wake of military campaigns, trade missions, or administrative surveys...

Nanomedicine is an emerging field that combines knowledge of nanotechnology and material science with pharmaceutical and biomedical sciences, aiming to develop nanodrugs with increased efficacy and safety. Compared to conventional therapeutics, nanodrugs manifest higher stability and circulation time, reduced toxicity and improved targeted delivery. Despite the obvious benefit, the accumulation of imaging agents and nanocarriers in the body following their therapeutic or diagnostic application generates concerns about their safety for human health...