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In this study, the arsenic (As) removal characteristics of a Mn–Fe binary coating formed on waste sand filter of an acid mine drainage treatment facility are investigated. Owing to the Mn–Fe binary coating forming on the surfaces of the sand grains, its potential for arsenic removal, particularly As(III), was evaluated and characterized through batch experiments and x-ray absorption spectroscopy. Sorption isotherms reveal that the Mn–Fe binary coating exhibits comparable removal efficiencies for As(III) and As(V) under low initial As concentrations. However, at higher initial As(III) and As(V) concentrations, the As(III) removal efficiency increases because of newly formed active adsorption sites from reductive dissolution of Mn. The oxidation of the As(III) and reduction of the Mn oxide phases are verified through As K-edge and Mn K-edge X-ray absorption near edge fine structure analysis. The outstanding As(III) removal efficiency of the Mn–Fe binary coating suggests synergy of Fe- and Mn-oxides, highlighting a potential application for this coating system. The natural formation of binary coating through acid mine drainage treatment reported in this study indicates that similar coating can form naturally in other environments, thus, providing plausible natural attenuation processes for arsenic immobilization.

Methane-oxidizing bacteria are crucial players in controlling methane emissions. This study aimed to isolate and characterize a novel wetland methanotroph to reveal its role in the wetland environment based on genomic information. Based on phylogenomic analysis, the isolated strain, designated as B8, is a novel species in the genus Methylocystis. Strain B8 grew in a temperature range of 15 °C to 37 °C (optimum 30–35 °C) and a pH range of 6.5 to 10 (optimum 8.5–9). Methane, methanol, and acetate were used as carbon sources. Hydrogen was produced under oxygen-limited conditions. The assembled genome comprised of 3.39 Mbp and 59.9 mol% G + C content. The genome contained two types of particulate methane monooxygenases (pMMO) for low-affinity methane oxidation (pMMO1) and high-affinity methane oxidation (pMMO2). It was revealed that strain B8 might survive atmospheric methane concentration. Furthermore, the genome had various genes for hydrogenase, nitrogen fixation, polyhydroxybutyrate synthesis, and heavy metal resistance. This metabolic versatility of strain B8 might enable its survival in wetland environments.

During isometric activation of airway smooth muscle (ASM), cross‐bridge cycling and ATP hydrolysis rates decline across time even though isometric force is sustained. Thus, tension cost (i.e., ATP hydrolysis rate per unit of force during activation) decreases with time. The “latch‐state” hypothesis attributes the dynamic change in cross‐bridge cycling and ATP hydrolysis rates to changes in phosphorylation of the regulatory myosin light chain (rMLC20). However, we previously showed that in ASM, the extent of rMLC20 phosphorylation remains unchanged during sustained isometric force. As an alternative, we hypothesized that cytoskeletal remodeling within ASM cells results in increased internal loading of contractile proteins that slows cross‐bridge cycling and ATP hydrolysis rates. To test this hypothesis, we simultaneously measured isometric force and ATP hydrolysis rate in permeabilized porcine ASM strips activated by Ca2+ (pCa 4.0). The extent of rMLC20 phosphorylation remained unchanged during isometric activation, even though ATP hydrolysis rate (tension cost) declined with time. The effect of cytoskeletal remodeling was assessed by inhibiting actin polymerization using Cytochalasin D (Cyto‐D). In Cyto‐D treated ASM, isometric force was reduced while ATP hydrolysis rate increased compared to untreated ASM strips. These results indicate that external transmission of force, cross‐bridge cycling and ATP hydrolysis rates are affected by internal loading of contractile proteins. An increase in internal loading of the contractile proteins resulting from actin cytoskeletal remodeling during isometric activation is associated with a decrease in cross‐bridge cycling rate and ATP hydrolysis rate.

Background/Objectives: Trefoil factor 1 (TFF1) plays a role in the mucus barrier. Methods: To evaluate the prevalence of TFF1 expression in cancer, a tissue microarray containing 18,878 samples from 149 tumor types and 608 samples of 76 normal tissue types was analyzed through immunohistochemistry (IHC). Results: TFF1 staining was detectable in 65 of 149 tumor categories. The highest rates of TFF1 positivity were found in mucinous ovarian carcinomas (76.2%), colorectal adenomas and adenocarcinomas (47.1–75%), breast neoplasms (up to 72.9%), bilio-pancreatic adenocarcinomas (42.1–62.5%), gastro-esophageal adenocarcinomas (40.4–50.0%), neuroendocrine neoplasms (up to 45.5%), cervical adenocarcinomas (39.1%), and urothelial neoplasms (up to 24.3%). High TFF1 expression was related to a low grade of malignancy in non-invasive urothelial carcinomas of the bladder (p = 0.0225), low grade of malignancy (p = 0.0003), estrogen and progesterone receptor expression (p < 0.0001), non-triple negativity (p = 0.0005) in invasive breast cancer of no special type, and right-sided tumor location (p = 0.0021) in colorectal adenocarcinomas. Conclusions: TFF1 IHC has only limited utility for the discrimination of different tumor entities given its expression in many tumor entities. The link between TFF1 expression and parameters of malignancy argues for a relevant biological role of TFF1 in cancer. TFF1 may represent a suitable therapeutic target due to its expression in only a few normal cell types.

Airway diseases such as asthma are triggered by inflammation and mediated by proinflammatory cytokines such as tumor necrosis factor alpha (TNFα). Our goal was to systematically examine the potential mechanisms underlying the effect of TNFα on airway smooth muscle (ASM) contractility. Porcine ASM strips were incubated for 24 h with and without TNFα. Exposure to TNFα increased maximum ASM force in response to acetylcholine (Ach), with an increase in ACh sensitivity (hyperreactivity), as reflected by a leftward shift in the dose–response curve (EC50). At the EC50, the [Ca2+]cyt response to ACh was similar between TNFα and control ASM, while force increased; thus, Ca2+ sensitivity appeared to increase. Exposure to TNFα increased the basal level of regulatory myosin light chain (rMLC) phosphorylation in ASM; however, the ACh‐dependent increase in rMLC phosphorylation was blunted by TNFα with no difference in the extent of rMLC phosphorylation at the EC50 ACh concentration. In TNFα‐treated ASM, total actin and myosin heavy chain concentrations increased. TNFα exposure also enhanced the ACh‐dependent polymerization of G‐ to F‐actin. The results of this study confirm TNFα‐induced hyperreactivity to ACh in porcine ASM. We conclude that the TNFα‐induced increase in ASM force, cannot be attributed to an enhanced [Ca2+]cyt response or to an increase in rMLC phosphorylation. Instead, TNFα increases Ca2+ sensitivity of ASM force generation due to increased contractile protein content (greater number of contractile units) and enhanced cytoskeletal remodeling (actin polymerization) resulting in increased tethering of contractile elements to the cortical cytoskeleton and force translation to the extracellular matrix. The tumor necrosis factor alpha (TNFα)‐induced increase in airway smooth muscle (ASM) force cannot be attributed to an enhanced [Ca2+]cyt response or to an increase in regulatory myosin light chain phosphorylation. Instead, TNFα increases Ca2+ sensitivity of ASM force generation due to increased contractile protein content and enhanced cytoskeletal remodeling resulting in increased tethering of contractile elements to the plasma membrane and force translation to the extracellular matrix.

We developed and applied a multidisciplinary approach to the impact of an accidentally spilled acid on the underlying geomedia and subsurface environment, based on the concept of geoecosystem. We used mineralogical, geochemical, microbiological, and ecotoxicological techniques to identify and assess the multiple aspects involved. First, we constructed a conceptual model for the acid interactions with the underlying subsurface environment by introducing the concept of a geoecosystem —a multicomponent system composed of inorganic, organic, and biological components to describe the subsurface environment. Second, we designed and manufactured a two dimensional cell to visualize acid transport through geomedia. Third, we hypothesized that the acids are neutralized through dissolution of minerals and protonation of functional groups on the surfaces of minerals and organic matter. We tested this hypothesis by conducting batch-type geomedia-acid reaction and surface titration experiments. Fourth, we observed changes in soil microbial communities before and after the acid exposure and neutralization treatment. Fifth, we performed flow-through experiments using columns packed with soil samples pre-contaminated with arsenic to investigate potential longer term, secondary effects of remnant acids on geoecosystems. Finally, we conducted ecotoxicological investigations using various geomedia and observed that suitability of the geoecosystem as a habitat deteriorated to different degrees depending on the respective systems’ acid neutralizing power. We conclude that a holistic understanding of the interactions among the multiple components of geoecosystems and subsequent estimation of the influenced area requires a multidisciplinary approach such as those used in this study. Based on the findings of this study, we propose geoecosystems’ vulnerability defined as the reciprocal of their acid-neutralizing capacity against the moving acid fronts and present this concept as central to a quantitative assessment of the impact of acid spills on geoecosystems. We also inventoried the essential components, factors, and parameters necessary in developing geoecosystems’ acid vulnerability assessment system.

Mineral processing requires large amounts of water, but, often in the remote locations of many mines, sufficient fresh water frequently cannot be supplied. Therefore, recycling of water is important in mineral processing and enhancing the efficiency of the liquid-solid separation and dewatering steps in mineral processing wastewater treatment is critical. The objectives of the study were to evaluate the effect of anionic flocculant dosage and sludge recycling (SR) on solid removal and sludge dewaterability. Different combinations of the flocculant dosage with and without SR were applied in a mineral-processing wastewater treatment pilot plant. Increasing the amount of flocculant dose of 1.1% v/v (flocculant solution to wastewater) did not significantly decrease the turbidity of the treated water, while the combination of a flocculant with SR increased the zeta potential. Increasing flocculant dose adversely affected dewaterability, although the dewaterability of the 0.6% v/v flocculant-treated sludge significantly increased after aging of the sludge. Sludge recycling was effective for increasing the dewaterability, and a flocculant dose of 1.1% v/v with SR led to formation of large flocs that were stable during aging and sonication.

The role of molecular weight during shish-kebab formation is an important issue in flow-induced polymer crystallization. In our previous study on the shish-kebab formation of polyethylene [ Macromolecules 40 , 3650–3654 (2007)], we have shown that ultrahigh molecular weight components are dominantly included in the shish. In contrast, in the same month (May 2007), a completely opposite experimental result was published for isotactic polypropylene [ Science 316 , 1014–1017 (2007)], wherein more low molecular weight components were found to be included in the shish than high molecular weight components. To understand this contradiction, we conducted small-angle neutron and X-ray-scattering experiments using blends of deuterated polyethylene and hydrogenated polyethylene with various molecular weights drawn just below the melting temperature at three drawing rates. We found that more low molecular weight components than high molecular weight components were included in the shish, even in polyethylene under such experimental conditions, and this tendency was enhanced as the drawing rate decreased. The results suggested that there are various mechanisms for shish-kebab formation that depend on the factors such as the type of flow fields, flow rate, type of polymer, temperature, molecular weight and molecular weight distribution. Small-angle neutron and X-ray scattering measurements were conducted on blends of deuterated polyethylene and hydrogenateted polyethylene with various molecular weights drawn just below the melting temperature at three drawing rates to study role of molecular weigh in shish-kebab formation. It was found that low molecular weight component was mainly included in shish for the present experimental condition. The result contradicts our previous result, showing that there are various shish-kebab formation mechanisms that are not known so far.

Open communication about patient safety concerns is necessary to enable a learning environment where lessons can be learned to improve patient safety, but nurses often hesitate to speak up even in situations where their patients may be at risk. One way to create a safe environment for speaking up is through the use of unit-level daily huddles. This study aimed to assess the effects of a 12-week huddle intervention on nine unit, nurse and patient care outcomes and describe nurses’ experiences with the intervention. We used a single group, pre- and post-test mixed-methods design, with a dominant quantitative thread, and a final sample of 89 staff nurses. The intervention was conducted in four surgical units in a tertiary teaching hospital in Seoul, Korea. The intervention included two educational workshops for huddle leaders, two workshops for staff nurses, and 12-week huddles with coaching visits. We collected quantitative data on nine outcomes using online surveys before and after the intervention and qualitative data on nurse experiences of the intervention after the intervention. Paired t-tests were used for quantitative data analysis, and content analysis was used for qualitative data. We examined four unit-level outcomes (organizational learning, situation monitoring, mutual support, and speaking-up climate), three nurse-level outcomes (promotive and prohibitive voice behaviors and job satisfaction), and two patient care outcomes (patient safety and quality of care). Significant improvements were found in six of the nine outcomes. Findings from the qualitative data confirmed the benefits of the intervention but also identified challenges to huddle participation. Patient safety huddles can contribute to a learning environment by flattening hierarchies and encouraging nurses to speak up regarding safety issues. Leadership is a key in role modelling and creating the foundation for a more collaborative patient safety culture in healthcare organizations, for example, through the use of daily huddles.

The phase behavior of amphiphilic Pluronic block copolymers in aqueous solution is of importance for a broad spectrum of practical applications but has not been fully exploited yet. Here, the phase behavior of the mixture of the Pluronic P65 and P105 triblock copolymer, (which have the same composition of PEO and PPO but the different molecular weight) and organic derivative, 5-methyl salicylic acid (5mS), in aqueous solution has been investigated by using small angle neutron scattering (SANS). According to the temperature and the 5mS concentration, SANS measurements showed that the P65-5mS mixtures sequentially transform into a random coil, sphere, vesicle, cylinder, and vesicle again, while the P105-5mS mixtures form spherical particles with two different sizes without any topological phase transition. Upon heating, the formation of two different kinds of the vesicle structure of amphiphilic block copolymer in aqueous solution is very unusual. This phase behavior was explained as the coupled effect of the simultaneous increase of the hydrophobicity of the polymer and the solubility of 5mS molecules upon heating. This result gives fundamental information for the practical use of Pluronic polymers in nano- and bio-science and it provides a simple route for the fabrication of the nanostructure without a complicated procedure.