Simple Composition Research Articles

Diffused Lattice Vibration and Ultralow Thermal Conductivity in the Binary Ln-Nb-O Oxide System.

In the pursuit of low thermal conductivity materials for thermal management, one always tries to increase the material entropy by increasing the number of components in the materials to scatter heat-carrying phonons. However, it also drastically increases the technological complexity to synthesize materials with the target complex composition. Here, a material family is presented with simple composition Ln3 NbO7 , which only contains binary oxides of Ln2 O3 (Ln = Dy, Er, Y, Yb) and Nb2 O5 . The thermal conductivities approach the theoretical minimum limit, where the large chemical inhomogeneity due to the charge disorder and fluctuation of bonding length in Ln3 NbO7 plays a major role. Despite the simple composition, Ln3 NbO7 demonstrates an unprecedentedly high scattering rate of vibration states, as confirmed by the highest elastic constant/thermal conductivity ratio, as well as the diffused wavevector-frequency dispersion. In contrast to the conventional wisdom that low thermal conductivity materials should be explored in the pool of "complex" multiple-component materials, this work points out an avenue to look into materials with simple composition but large internal chemical inhomogeneity, which would be of both scientific and technological significance in the fields of thermal barrier coating, thermoelectric materials, etc.

A microfluidic platform for multi-size 3D tumor culture, monitoring and drug resistance testing

The establishment of a miniaturized platform capable of microscale control for sequential, coordinated, and throughput biomimetic tumor manipulation and analysis offer a high degree of biological and clinical relevance to cancer therapy and pharmaceutical research. In this study, we developed a microfluidic system with well-established microwell arrays and simple double-layer composition that allows massive fabrication of biomimetic multi-size 3D tumors and their simultaneous manipulation and orthogonal analysis. Serial manipulations including cell localization, array-like self-assembly/cultivation, and dynamic analysis of different types of 3D tumors, were accomplished in the microfluidic device. We demonstrated that the microfluidic platform is stable and throughput cell trapping and tumor generation with quantity uniform. Furthermore, on-chip monitoring and throughput analysis of tumor phenotypes and responses to culture and different chemotherapies were also achieved in the device. The microfluidic advancement offers a new methodological approach for the development of high-performance and multifunctional 3D tumor systems and for tissue-mimicking cancer research and therapy evaluation. This microfluidic platform, which has the capability of multiple control in time and space, holds great potential for applications in the fields of tumor biology, tissue engineering, and clinical medicine.

Triacylglycerol Production in the Snow Algae Chlamydomonas nivalis under Different Nutrient Conditions.

Eukaryotic microalgae have been known for high competency in the accumulation of triacylglycerol (TAG), a representative class of storage lipid. The snow algal species, Chlamydomonas nivalis, is a unique green eukaryotic microalga that can grow and survive in a wide range of temperatures. Although a few metabolomic studies of C. nivalis were conducted, no study has reported on TAG accumulation in C. nivalis. Herein, the present work aimed to investigate TAG production in C. nivalis under nutrient-starved conditions at 22 °C. Compared to phosphorus starvation, C. nivalis under nitrogen starvation showed a less severe growth defect, greater capacity for TAG production, and simple acyl composition in TAG enriched with 18:1. These features suggest that C. nivalis may be a significant model species to investigate glycerolipid metabolism for basic and applied research.

Optimization of English Speaking Skill and English Grammatical Competence of Second Semester College Students in English Literature of Bung Hatta University Through Role-play Technique: Classroom Action Research of English As Foreign Language

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Synthesis of nanocellulose/cobalt oxide composite for efficient degradation of Rhodamine B by activation of peroxymonosulfate

In recent years, nanofibrous materials derived from biopolymers have attracted more interest due to their numerous applications. In our study, a simple composite of cellulose nanocrystals, and cobalt oxide nanoparticles was elaborated using sodium borohydride as a chemical reducer. It has been shown that Co3O4 nanoparticles were grown on the surface of cellulose nanocrystals. An important quantity of cobalt oxide nanoparticles was detected using ICP-OES (13.5 g contained in 100 mg of the composite). The size, the morphology and the thermal stability of the composite and the obtained nanoparticles were studied using X-ray powder diffraction, Fourier-transform infrared spectroscopy, Ultraviolet-Visible spectrophotometry, Scanning electron microscopic and Transmission electron microscopic. Our obtained material was used for the degradation of Rhodamine B and it was succeeded in degradation of Rhodamine B within very short period of time (16 min). The catalytic degradation of Rhodamine B was investigated and analyzed with UV-Visible absorption spectra.

Scoring system for optimal management of acute traumatic patellar dislocation: A multicenter study

BackgroundIn first-time acute traumatic patellar dislocations, numerous anatomic and clinical factors are complicatedly associated and should be comprehensively considered for the optimal management of conservative or surgical intervention. The purpose of this study was to establish a scoring system, using a concept that is not complicated and easily used in clinic. MethodsOf 131 first-time acute traumatic patellar dislocations, 81 patients (51 females, 30 males) with an average age of 19.6 (95%CI, 17.5–21.6) years and an average follow-up duration of 17.1 (95% CI, 12.3–21.9) months, who underwent conservative treatment after first-time dislocations, were reviewed. Based on the odds ratios applying logistic regression analysis, the scoring system was established. ResultsThe scoring system (total: 10 points) had simple composition of age <20 (2 points), sports injury (1 points), hemarthrosis (1 points), and image findings of a bony fragment (3 points), lateral shift of the patella (1 points), and trochlear dysplasia (2 points). A threshold score of 6.5 was determined using the area under receiver operating characteristic curve of 0.893 (p < 0.0001). In logistic regression analysis, a score of ≥7 was shown to be a dominant factor for recurrence (OR = 27.1, p < 0.0001). Furthermore, the association between the score and recurrence risk was as follows: a score of ≤4 = low risk (1/21 cases, 5%); a score of 5–7 = medium risk (13/27 cases, 48%); a score of ≥8 = high risk (30/33 cases, 91%). ConclusionsBased on the simple scoring system, patients who scored ≥8 were considered suitable for surgical treatment because of the high rate of recurrence, whereas those who scored ≤4 were considered suitable for conservative treatment because of the low rate of recurrence.

A Versatile Theranostic Nanoemulsion for Architecture-Dependent Multimodal Imaging and Dually Augmented Photodynamic Therapy.

To design a clinically translatable nanomedicine for photodynamic theranostics, the ingredients should be carefully considered. A high content of nanocarriers may cause extra toxicity in metabolism, and multiple theranostic agents would complicate the preparation process. These issues would be of less concern if the nanocarrier itself has most of the theranostic functions. In this work, a poly(ethylene glycol)-boron dipyrromethene amphiphile (PEG-F54 -BODIPY) with 54 fluorine-19 (19 F) is synthesized and employed to emulsify perfluorohexane (PFH) into a theranostic nanoemulsion (PFH@PEG-F54 -BODIPY). The as-prepared PFH@PEG-F54 -BODIPY can perform architecture-dependent fluorescence/photoacoustic/19 F magnetic resonance multimodal imaging, providing more information about the in vivo structure evolution of nanomedicine. Importantly, this nanoemulsion significantly enhances the therapeutic effect of BODIPY through both the high oxygen dissolving capability and less self-quenching of BODIPY molecules. More interestingly, PFH@PEG-F54 -BODIPY shows high level of tumor accumulation and long tumor retention time, allowing a repeated light irradiation after a single-dose intravenous injection. The "all-in-one" photodynamic theranostic nanoemulsion has simple composition, remarkable theranostic efficacy, and novel treatment pattern, and thus presents an intriguing avenue to developing clinically translatable theranostic agents.

A new family of sodium niobate-based dielectrics for electrical energy storage applications

Although tremendous achievements have been made in enhancing recoverable energy storage density (Wrec) of lead-free dielectric ceramics for electrical energy storage applications in recent years, these ceramics with high Wrec still have two disadvantages: complex chemical composition and difficult preparation process. In this work, we selected NaNbO3 (NN)-based ceramics as base materials and used Bi2O3 as a sintering aid to reduce porosity and enhance dielectric breakdown strengths. Encouragingly, high Wrec, simple chemical composition and facile preparation process were simultaneously realized in 0.77NaNbO3-0.23BaTiO3 (0.77NN-0.23BT) ceramics. A large Wrec of 1.5 J cm−3 at 175 kV cm−1 and excellent thermal stability (variation of Wrec < 15% over the temperature range of 20˜140 °C) were simultaneously achieved in 0.77NN-0.23BT ceramics. More importantly, this work could bring out the development of a series of NN-based ceramics for electrical energy storage in the future such as NN-ABO3 (A = Ca and Sr; B = Ti and Zr).

Improving the film-forming ability of BaTiO3/epoxy resin suspension by adjusting the solvent composition for the fabrication of embedded capacitance materials

Embedded capacitance materials (ECMs) are gradually taking the place of traditional discrete capacitors in the fabrication of high-end electronic devices. However, the exploration of suspensions with simple compositions and improved performance remains an important topic for the further development of ECMs. In this work, commonly used auxiliaries are not employed, and ethanol is added to a BaTiO3/epoxy resin ethyl acetate suspension, which improves the film-forming ability. The corresponding ECMs show increased mechanical and electrical performance due to the better dispersion of the BaTiO3 nanoparticles. The fabricated embedded capacitors have low tolerances and can pass reliability tests, which verifies their applicability in printed circuit board manufacturing.

More superior pyroelectric performance of synthesized dravite by high-pressure solid-state method

It’s of great significance to explore the synthesis of tourmaline with simple chemical composition to study the mechanism of its pyroelectric properties due to the presence of crystal defects and isomorphous substitution in natural tourmaline. In the present work, dravite is firstly synthesized by high pressure solid-state method at 5-6 GPa and 550-650 °C. X-ray powder diffraction and electron microprobe analysis data indicate that the synthesized sample is the compound of the dravite with the formula of NaMg3Al6Si6B3O27(OH)4 and a small amount of SiO2. Compared with the natural dravite, the pyroelectric coefficient of the synthesized dravite is improved by an order of magnitude due to the great increase of the intrinsic dipole moment in synthesized dravite. The temperature dependent infrared spectra shows that the dipole moment of each ionic group in the synthesized dravite increases with temperature, leading to the raise of the pyroelectric coefficient with the increment of temperature. And in all ionic groups, [SiO4] tetrahedron and [BO3] triangle are the most important ionic groups that caused the pyroelectricity of tourmaline.

A High Efficient Method to Isolate Exosomes from Small Intestinal Epithelium.

The intestinal epithelium is an important receptor that is not only exposed to nutrients but also to pathogens, such as ingested toxins, bacterial flora, and their metabolites. The sensory information is communicated to extensive endocrine, neural, immune systems, and the exosomes acts as carriers of communication from cell-to-cell. Isolation of exosomes from small intestinal epithelium remains more complex to obtain as a source of exosomes, as it contains varying proportions of exosomes derived from many different cells. Current studies on exosomes have been largely performed using supernatants of cultured cells. This is because, in a cell culture, the origin of exosomes can be determined and isolation of exosomes devoid of 'contaminating' proteins, lipids, and sugars involves relatively simple composition of most culture media facilitates. However, this is hard to achieve in intestinal epithelial cells (IECs) due to several technical issues, including recapitulation of in vivo physiology, operational simplicity, culture stability over time, and assay throughput. Meanwhile, separation of exosomes from a specific cell type remains to be a considerable problem, as the isolated supernatant exosomal fraction may represent only a small fraction of the total instead of reflecting the overall situation. Herein, we proposed an efficient protocol for enrichment of exosomes from the interstitial space of small intestinal epithelium. This method maintains the integrity of the vesicles as well as their contents. Also, it may help to better understand the properties of exosomes and explore their role in cell-to-cell communication of small intestinal epithelium.

Design, antimicrobial activity and mechanism of action of Arg-rich ultra-short cationic lipopeptides.

The increasing emergence of multidrug-resistant microorganisms represents one of the greatest challenges in the clinical management of infectious diseases, and requires the development of novel antimicrobial agents. To this aim, we de novo designed a library of Arg-rich ultra-short cationic antimicrobial lipopeptides (USCLs), based on the Arg-X-Trp-Arg-NH2 peptide moiety conjugated with a fatty acid, and investigated their antibacterial potential. USCLs exhibited an excellent antimicrobial activity against clinically pathogenic microorganisms, in particular Gram-positive bacteria, including multidrug resistant strains, with MIC values ranging between 1.56 and 6.25 μg/mL. The capability of the two most active molecules, Lau-RIWR-NH2 and Lau-RRIWRR-NH2, to interact with the bacterial membranes has been predicted by molecular dynamics and verified on liposomes by surface plasmon resonance. Both compounds inhibited the growth of S. aureus even at sub MIC concentrations and induced cell membranes permeabilization by producing visible cell surface alterations leading to a significant decrease in bacterial viability. Interestingly, no cytotoxic effects were evidenced for these lipopeptides up to 50–100 μg/mL in hemolysis assay, in human epidermal model and HaCaT cells, thus highlighting a good cell selectivity. These results, together with the simple composition of USCLs, make them promising lead compounds as new antimicrobials.

A Thermal Study of a Simple Al−CuO Pyrotechnic Crackle Composition

AbstractThe reaction temperature in ignited samples of a novel, chemically simple pyrotechnic crackle composition was monitored at 1 ms intervals by means of a small embedded thermocouple. Analysis of the results reveals that an exothermic reaction is detectable at temperatures as low as 500 K. The reaction is found to progress in at least three – and probably four – steps that correlate well with similar findings from the study of nanocomposites of the same composition. The first two steps are shown to be associated with the crackle's delay phase. The transition to the explosive phase is shown to occur at a temperature significantly above the melting point of aluminum, being triggered at or beyond the temperature of operation of the third reaction step. The results provide a behavioral baseline for the future study of more complex crackle compositions.

An Easy Method for Cryopreservation of Zebrafish (Danio rerio) Sperm.

We developed an easy, efficient, and cheap protocol for zebrafish sperm cryopreservation carried out on dry ice (20 min) using simple composition solution (200 mM glucose, 40 mM KCl, 30 mM Tris, pH = 8.0). The average efficiency of the present cryopreserve method was between 10% and 20% (expressed as fertilization rate). The experiments were conducted and repeated at two different locations, in different countries, yielding very similar results, showing the reproducibility and applicability of the method.

The Fornax 3D project: dust mix and gas properties in the centre of early-type galaxy FCC 167

Galaxies continuously reprocess their interstellar material. We can therefore expect changing dust grain properties in galaxies that have followed different evolutionary pathways. Determining the intrinsic dust grain mix of a galaxy helps in reconstructing its evolutionary history. Early-type galaxies occasionally display regular dust lanes in their central regions. Owing to the relatively simple geometry and composition of their stellar bodies, these galaxies are ideal to disentangle dust mix variations from geometric effects. We therefore modelled the various components of such a galaxy (FCC 167). We reconstructed its recent history and investigated the possible fate of the dust lane. Observations from MUSE and the Atacama Large Millimeter/submillimeter Array (ALMA) reveal a nested interstellar medium structure. An ionised-gas disc pervades the central regions of FCC 167, including those occupied by the main dust lane. Inward of the dust lane, we also find a disc/ring of cold molecular gas where stars are forming and HII regions contribute to the ionised-gas emission. Further in, the gas ionisation points towards an active galactic nucleus and the fuelling of a central supermassive black hole from its surrounding ionised and molecular reservoir. Observational constraints and radiative transfer models suggest the dust and gas are distributed in a ring-like geometry and the dust mix lacks small grains. The derived dust destruction timescales from sputtering in hot gas are short, and we conclude that the dust must be strongly self-shielding and clumpy or will quickly be eroded and disappear. Our findings show how detailed analyses of individual systems can complement statistical studies of dust-lane ETGs.

Aerogel-Directed Energy-Storage Films with Thermally Stimulant Multiresponsiveness.

Phase change materials offer enormous potential for thermal energy storage due to their high latent heat and chemical stability. Researchers have developed numerous innovative strategies to overcome the leakage of organic phase change materials and enhance thermal performance. However, the manufacture of form-stable, free-standing energy storage films based on phase change materials with high latent heat remains difficult. Therefore, the present study focused on the production of free-standing, form-stable energy storage films with high phase-change enthalpy and thermally stimulant multiresponsiveness from the simple composite of paraffin with a polytetrafluoroethylene/silica (PTFE/SiO2) aerogel framework, where paraffin was effectively confined in PTFE/SiO2. The resulting paraffin/PTFE/SiO2 films exhibited a large phase change enthalpy (128 J/g) at a paraffin content of 62.8 wt %. The temperature-dependent wettability, transmittance, and mechanical properties of this composite film have also been investigated.

Milk Lipids: A Complex Nutrient Delivery System.

The evolution of lactation and the composition, structures, and functions of milk's biopolymers illustrates that the Darwinian pressure on lactation selected for gene products with considerable structural complexity and diverse functions within the digestive system. For example, complex sugar polymers - oligosaccharides - possess unique properties in guiding the growth of intestinal bacteria that are not possible by feeding their simple sugars. The proteins of milk are diverse with some exhibiting enzymatic activities towards other milk components rendering those components both more digestible but also releasing biologically active products. Thus, research into milk's biopolymers has been most enlightening when milk was investigated for the formation and disassembly of its structures and for the functions within the infant. To date however, the most complex structure in mammalian milk, the fat globule, has not been effectively examined beyond its simple composition. The globules of milk are heterogeneous in size, composition, and function. With new research tools, scientists are beginning to understand the mechanisms that control the assembly of globules in the mammary gland and the disassembly within the infant.

Elemental Se: fundamentals and its optoelectronic applications

Elemental selenium (Se), as the oldest photovoltaic material, has many advantages such as a direct band gap, earth-abundance, simple composition, nontoxicity, and a low melting point for optoelectronic applications.

The use of a fertile doubled haploid apple line for QTL analysis of fruit traits.

Apple is an economically important crop, and various approaches to genetic analysis in breeding programs have been attempted, including the production of doubled haploid (DH) lines, which are genetically homozygous. In this study, we used a DH line for QTL analyses, for the first time in a fruit tree, expecting it to simplify the analysis of the inheritance of quantitative traits and thus to enhance QTL detection power. Using an F1 population from ‘Prima’ × ‘Apple Chukanbohon 95P6’ (DH), we constructed a genetic map of ‘Prima’, and identified 19 QTLs for 13 traits. These QTLs had comparatively high LOD scores and explained a large part of the variation of the phenotypes. In particular, acidity, juice browning, and skin splitting clearly segregated at a 1:1 ratio, consistent with the segregation of the alleles at the detected QTLs in linkage group 16; these traits appeared to be regulated by single genes, despite general consideration that they are quantitative traits. Using this simple genetic composition of the F1 population, we concluded that the skin splitting of apple fruit has recessive inheritance, and that the allele for splitting is tightly linked with those for high acidity and low juice browning in ‘Prima’.

Stretchable, Bifacial Si-Organic Hybrid Solar Cells by Vertical Array of Si Micropillars Embedded into Elastomeric Substrates.

Stretchable electronics has enabled many unforeseen applications in a variety of fields. Mechanical design concepts to achieve the stretchability without affecting the device functionality, however, are limited to few known practices, such as mechanical buckling, serpentine shape, or simple elastomeric composites. In this paper, we propose another mechanics design principle for high stretchability (>100%) based on the composite of vertical array of Si micropillars embedded into elastomer poly(dimethylsiloxane). The orthogonalization of active functional elements to applied strain direction enables highly stretchable electronic devices, where the applied strain is mostly absorbed into elastomer on interpillar space. On the other hand, the vertical pillars do not experience any noticeable strain at all. As a proof-of-concept demonstration, we fabricate stretchable Si-organic hybrid solar cells using such a design and the cell shows reasonable level of cell efficiency compared with planar counterparts. The cell can be stretched reversibly without any noticeable performance degradation. Furthermore, the cell can be operated in a bifacial mode by employing stretchable, transparent Ag nanowire-based electrodes. The mechanical design for stretchability demonstrated here would provide new opportunities for stretchable electronics.