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Co3O4 was synthesized on carbon paper (CP) using a facile method to improve electrochemical nitrate-toammonia conversion efficiency. The resulting Co3O4-CP electrode demonstrated an exceptional Faradaic efficiency of almost 100% across a broad range of application conditions, with a peak NH3 yield of 3.43 mmol h-1 cm-2 (2.25 mol gCo-1 h-1). [ABSTRACT FROM AUTHOR]

The presence of progesterone receptor (PR) and PR isoform B (PRB) in breast cancer is generally correlated with better clinical outcomes. Additionally, the significance of hormone-independent effects of PR/PRB correlated with better prognosis has been reported in non-small cell lung cancer (NSCLC). However, the detailed mechanism of that still remains unclear. In this study, we examined how microRNAs (miRNAs) could contribute to tumor inhibition via PR/PRB expression, in order to find miRNAs that have tumoragnostic effects between breast cancer and NSCLC. We obtained miRNA data using human tissues of breast cancer and NSCLC from The Cancer Genome Atlas (TCGA) database and PCR array from NSCLC patients of our cohort. Subsequently, we examined the function of the miRNA through in vitro study using breast cancer cell lines. As a result, only let-7b expression was significantly correlated with PR expression in both cancers. Additionally, the expression of let-7b significantly inhibited cell proliferation by inducing PR and PRB expression in breast cancer cell lines. However, the positive correlation of let-7b and PRB required a mediated factor, E2 promoter binding factor 1 (E2F1), obtained from TCGA database analysis. In vitro experiments showed that let-7b significantly inhibited E2F1, and E2F1 significantly inhibited PRB. This study revealed that PRB inhibits the proliferation of breast cancer cells by the let-7b-E2F1 interaction. In addition, the immunohistochemical analysis in NSCLC was also consistent with these in vitro data. Our results could contribute to developing novel therapeutic strategies for patients with PR/PRB-positive cancer by targeting let-7b or PRB expression in breast cancer and possibly NSCLC. [ABSTRACT FROM AUTHOR]

Arabidopsis halleri ssp. gemmifera is classified as Cd and Zn hyperaccumulator plant; however, the disparity accumulation preferences in organs (root, stem and leaves) between cadmium and zinc seems less understandable. Therefore, this study aimed to portray accumulation behaviour toward the presence of Cd and Zn in the hydroponic method employing A. halleri ssp. gemmifera. The experiment was conducted by applying this plant using 2 and 300 µM of Cd, and 2 and 200 µM Zn, together with 20% Hoagland solution for 7 days, separately. The results showed that Zn in the medium was uptake faster than Cd. Furthermore, increasing Cd/Zn supply at the medium resulted in an increasing accumulation of Cd/Zn in the organs of the plant. In both Cd treatments, the accumulation followed the order of stem>root>leaves, indicating Cd transportation to the upper part has occurred during this period. The same accumulation preference pattern was also reported in the 200 µM Zn supply. However, at 2 µM Zn supply, Zn accumulation was mainly found in the leaves, followed by the root and stem. A. halleri ssp. gemmifera uptake Zn faster from the medium and translocate rapidly to the leaves at low-level Zn supply. Increasing Zn supply concentration might inhibit the translocation of Zn from stem to leaves. Meanwhile, regardless of Cd supply concentrations, this plant could only translocate Cd to the stem mostly within a short-time exposure period. Therefore, this study concluded that A. halleri ssp. gemmifera exhibited different accumulation responses when exposed to different Cd and Zn supply concentrations. [ABSTRACT FROM AUTHOR]

This study focuses on how to solve cadmium (Cd) contamination in soil because this contaminant decreases soil quality. Soil remediation using the hyperaccumulator plants is an optional process to solve soil contamination. Arabidopsis halleri ssp. gemmifera (hereinafter referred to as A. halleri), is one of the candidate plants expected to be used for phytoremediation of Cd contaminated soil. The A. halleri promote solubilization of Cd in the soil directly or indirectly using its secreted root exudate. However, the effect of the metabolites profile of this plant to Cd uptake from contaminated soil is still unclear. The purpose of this study was to examine the contribution of root exudates of A. halleri to extract Cd in the soil. Cd-contaminated soil used in this study was a farmland soil containing 5.8 mg kg-1 of Cd and 648 mg kg-1 of Zn taken from Tome City, Miyagi Prefecture, Japan. Soil leaching tests were conducted using the solution containing the root exudates from A. halleri plant. The accelerating effect of root exudates of A. halleri on solubilization of Cd is fundamental information to construct the benefit of phytoremediation. [ABSTRACT FROM AUTHOR]

As shown in our previous studies, the intratrachealadministration of STC1 (stanniocalcin-1) ameliorates pulmonary fibrosis by reducing oxidative and endoplasmic reticulum stress through the uncoupling of respiration in a bleomycin-treated mouse model. However, the overall effect of STC1 on metabolism was not examined. Therefore, we first conducted a comprehensive metabolomics analysis to screen the overall metabolic changes induced by STC1 in an alveolar epithelial cell line using capillary electrophoresis time-of-flight mass spectrometry. The results were subsequently validated in multiple alveolar epithelial and fibroblast cell lines by performing precise analyses of each substance. STC1 stimulated glycolysis, acetyl-CoA synthesis, and the methionine and cysteine-glutathione pathways, which are closely related to the uncoupling of respiration, modulation of epigenetics, and reduction in oxidative stress. These results are consistent with our previous study. Subsequently, we focused on the inhibitory factor SMAD7, which exerts an antifibrotic effect and is susceptible to epigenetic regulation. STC1 upregulates SMAD7 in an uncoupling protein 2-dependent manner, induces demethylation of the SMAD7 promoter region and acetylation of the SMAD7 protein in human alveolar epithelial and fibroblast cell lines and a bleomycin-treated mouse model, and subsequently attenuates fibrosis. The antifibrotic effects of STC1 may partially depend on the regulation of SMAD7. In the evaluation using lung tissue from patients with idiopathic pulmonary fibrosis, SMAD7 expression and acetylation were high in the alveolar structure-preserving region and low in the fibrotic region. The intratracheal administration of STC1 may prevent the development of pulmonary fibrosis by regulating the metabolism-mediated epigenetic modification of SMAD7 in patients. [ABSTRACT FROM AUTHOR]

A metal spark generated by grinding carbon steel has been recognized proceeding multiple bursting events, akin to the luminous branching fireworks. The mechanism of successive fragmentation observed in carbon steel spark, however, has not been elucidated yet. In the present study, we develop a new comprehensive analytical framework for estimating the droplet size of carbon steel sparks, time of flight, and time-variant temperature, combined with high-speed images of the spreading sparks, for the quantitative discussion of the timescale of bursting metal sparks. We find that the flight time to burst for a mother droplet is independent of the content of carbon, corresponding to the Fourier number for the molecular diffusion of unity. The successive fragmentation of carbon steel sparks is rate-controlled by the molecular diffusion of ambient oxygen inside the droplet. Since the measured temperature indicates that the heat is produced by the oxidation of iron, the successive fragmentation stops when the iron in the spark is fully oxidized, immediately becoming a solid particle. [ABSTRACT FROM AUTHOR]

This research presents the development of an online speaking test of English for students at the end of primary and beginning of secondary school education in state schools in Uruguay. Following the success of the Plan Ceibal one computer-tablet per child initiative, there was a drive to further utilize technology to improve the language ability of students, particularly in speaking, where the majority of students are at CEFR levels pre-A1 and A1. The national concern over a lack of spoken communicative skills amongst students led to a decision to develop a new speaking test, specifically tailored to local needs. This paper provides an overview of the speaking test development and validation project designed with the following objectives in mind: to establish, track, and report annually learners' achievements against the Common European Framework of Reference for Languages (CEFR) targeting CEFR levels pre-A1 to A2, to inform teaching and learning, and to promote speaking practice in classrooms. Results of a three-phase mixed-methods study involving small-scale and large-scale trials with learners and examiners as well as a CEFR-linking exercise with expert panelists will be reported. Different sources of evidence will be brought together to build a validity argument for the test. The paper will also focus on some of the challenges involved in assessing young learners and discuss how design decisions, local knowledge and expertise, and technological innovations can be used to address such challenges with implications for other similar test development projects. [ABSTRACT FROM AUTHOR]

When metal is cut and ground with a grinder, chips are heated by friction and oxidation, and scattered, which look like sparks. The temperature varies depending on the particle properties with changing in time accordingly. It is difficult to obtain quantitative information simultaneously such as each particle size, unsteady velocity, and temperature varying over 1000 K. In the present study, we developed a new framework for estimating the particle size of pure iron sparks by fitting the equation of motion to the trajectory of the time􀀎resolved images, and for calculating the spark temperature by solving the unsteady thermal equation. The validity is convinced through the comparison with the high􀀎speed images, SEM images, and temperature measurement results. We succeeded in finding the time􀀎dependent changes in temperature and heat balance, which are closely related to the colors of sparks, starting from the grinder to the end. The heat production by surface oxidization deteriorates as the spark decelerates due to the aerial drag force. The heat dissipation of heat transfer is dominantly affected by the spark temperature rather than the boundary layer thickness. The effect of the heat of fusion is insignificant in the temperature change. [ABSTRACT FROM AUTHOR]

For attitude control and orbital transfer of satellites, bipropellant thrusters are crucial components in space propulsion systems. The overall performance of the thruster is evaluated by the specific impulse (ISP), which directly determines the lifetime and propellant mass of satellites. Therefore, in the present study, a new theoretical framework is firstly proposed to predict ISP directly from injection conditions and nozzle configurations by considering the distribution of mixture and mass flow rates in the thrust chamber. As the performance index of the combustion chamber, the characteristic velocity is formulated. The frozen flow assumption is applied to the nozzle internal flow to calculate the thrust coefficient. The analytical results of ISP are compared to the corresponding combustion test of a 10N bipropellant thruster using a propellant combination of mixed nitrogen oxides with 3% nitric oxide and monomethyl hydrazine, which validates the prediction model proposed. [ABSTRACT FROM AUTHOR]

In bi-propellant thrusters, impinging type injectors are widely used to deliver propellants to a combustion chamber. By impinging the jet streams of fuel and oxidizer, the spray spreads while the two liquids mix. To design the injectors, several correlations related to injection conditions have been proposed (e.g., Rupe factor), and practically utilized over the last half-century. However, the physical meanings of the past correlations are not well understood, because the essential scale of the spray structure is elusive. In this paper, we derive the global length scale of the spray produced by impinging injectors of unlike doublet, fuel-oxidizer-fuel triplet, and oxidizer-fuel-oxidizer triplet in a consistent manner. The unified length scale is found representing the spray width ratio of oxidizer to fuel evidenced by comprehensive cold-flow tests including several past studies, covering various parameters such as injector types, nozzle diameters, physical properties of working liquids, and injection velocities. Finally, we clearly provide the physical meaning based on practical correlations in a phenomenological sense. [ABSTRACT FROM AUTHOR]

Epidermal growth factor receptor–tyrosine kinase inhibitor (EGFR-TKI) resistance is one of the most important problems in lung cancer therapy. Lung adenocarcinoma with EGFR-TKI resistance was reported to have higher abilities of invasion and migration than cancers sensitive to EGFR-TKI, but the function of matrix metalloproteinases (MMPs) has not been explored in EGFR-TKI–resistant lung adenocarcinoma. This study aims to clarify the significance of MMP-1 in EGFR-TKI–resistant lung adenocarcinoma. From the results of in vitro studies of migration and invasion assays using EGFR-TKI–sensitive and –resistant cell lines and phosphorylation antibody arrays using EGF and rapamycin, we first demonstrate that overexpression of MMP-1, which might follow activation of a mammalian target of rapamycin (mTOR) pathway, plays an important role in the migration and invasion abilities of EGFR-TKI–resistant lung adenocarcinoma. Additionally, immunohistochemical studies using 89 cases of lung adenocarcinoma demonstrate that high expression of MMP-1 is significantly correlated with poor prognosis and factors such as smoking history and the subtype of invasive mucinous adenocarcinoma. These are consistent with the results of this in vitro study. To conclude, this study provides insights into the development of a possible alternative therapy manipulating MMP-1 and the mTOR signaling pathway in EGFR-TKI–resistant lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

The Shozu-gawa river, located in the Aomori Prefecture, northern Japan, is affected by volcanic activities and acid thermal waters. The river is unique because both solid arsenic (As; as orpiment, As2S3) and dissolved As are supplied to the river from the uppermost caldera lake (Usori-ko Lake) and thermal ponds. The watershed is an excellent site for investigating the fate of different As species in a fluvial system. Upstream sediments near the caldera lake and geothermal ponds are highly contaminated by orpiment. This solid phase is transported as far as the mouth of the river. On the other hand, dissolved As is removed from the river system by hydrous ferric oxides (HFOs); however, HFO formation and removal of dissolved As do not occur in the uppermost area of the watershed, resulting in further downstream transport of dissolved As. Consequently, upstream river sediments are enriched in orpiment, whereas As(V), which is associated with HFOs in river sediments, increases downstream. Furthermore, orpiment particles are larger, and possibly heavier, than those of HFO with sorbed As. Fractionation between different chemical states of As during transport in the Shozu-gawa river is facilitated not only by chemical processes (i.e., sorption of dissolved As by HFOs), but also by physical factors (i.e., gravity). In contrast to acid mine drainage (AMD), in some areas of the Shozu-gawa river, both solid forms of As (as sulfide minerals) and dissolved As are introduced into the aquatic system. Considering that the stabilities of sulfide minerals are rather different from those of oxides and hydroxides, river sediments contacted with thermal waters possibly act as sources of As under both aerobic and anaerobic conditions. [ABSTRACT FROM AUTHOR]

Abstract  The merC gene from Acidithiobacillus ferrooxidans functions as a mercury uptake pump. MerC protein localizes in the cytoplasmic membrane of plant cells. When Arabidopsis thaliana and tobacco plants were transformed with the merC gene under the control of the Cauliflower mosaic virus 35S promoter, the resulting overexpression of merC rendered the host plants hypersensitive to Hg2+ and they accumulated approximately twice as much Hg2+ ion as the wild type plants. Thus, bacterial mercuric ion transporters such as MerC may be useful molecular tools for producing transgenic plants that hyperaccumulate Hg2+ ion. [ABSTRACT FROM AUTHOR]

By means of functional screening using the cadmium (Cd)-sensitive ycf1 yeast mutant, we have isolated a novel cDNA clone, DcCDT1, from Digitaria ciliaris growing in a former mining area in northern Japan, and have shown that it confers Cd tolerance to the yeast cells, which accumulated almost 2-fold lower Cd levels than control cells. The 521 bp DcCDT1 cDNA contains an open reading frame of 168 bp and encodes a deduced peptide, DcCDT1, that is 55 amino acid residues in length, of which 15 (27.3%) are cysteine residues. Five DcCDT1 homologs (here termed OsCDT1–OsCDT5) have been identified in rice, and all of them were up-regulated to varying degrees in the above-ground tissues by CdCl2 treatment. Localization of green fluorescent protein fusions suggests that DcCDT1 and OsCDT1 are targeted to both cytoplasmic membranes and cell walls of plant cells. Transgenic Arabidopsis thaliana plants overexpressing DcCDT1 or OsCDT1 displayed a Cd-tolerant phenotype and, consistent with our yeast data, accumulated lower amounts of Cd when grown on CdCl2. Collectively, our data suggest that DcCDT1 and OsCDT1 function to prevent entry of Cd into yeast and plant cells and thereby enhance their Cd tolerance. [ABSTRACT FROM AUTHOR]