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Red soils in subtropical regions are often low in available phosphorus (P), a vital plant nutrient. Phosphate‐solubilizing microorganisms (PSMs) can release P from phosphate reservoir, making it accessible to plants. However, the complex interactions between PSMs and minerals in red soils are not yet fully understood. In this study, we investigated the effects of Aspergillus niger, a typical phosphate‐solubilizing fungus (PSF), on phosphate dissolution in two representative red soils – an acidic soil and an alkaline soil. In the acidic red soil, the fungal abundance reached 3.01 × 10 7 cfu g−1 after a 28‐day incubation period, with respiration of ~2000 mg C kg−1. The secretion of oxalic acid promoted P release from inorganic phosphate (from ~1 to 187 mg kg−1). Additionally, the contents of amorphous Fe/Al oxides decreased, which otherwise could have contributed to P sorption in the soil. In contrast, P availability declined in the alkaline red soil after the addition of A. niger, regardless of the P source (inorganic or organic phosphate). Meanwhile, the fungal respiration decreased to ~780 mg C kg−1. Therefore, alkaline red soils with abundant carbonates are susceptible to P deficiency due to both the diminished function of PSMs and strong soil buffering. These findings have important implications for sustainable agriculture on alkaline red soils, as they suggest that the use of PSMs to improve P availability may be limited. [ABSTRACT FROM AUTHOR]

Dental caries is one of the most common disorders in dentistry. Typically, it is caused by the dissolution of the tooth mineral due to cariogenic organisms. Bioapatite is vulnerable to acid‐etching ascribed to a variety of substitutions. This study applied Pb2+ cations to probe the dissolution of synthetic carbonated hydroxylapatite (CHAp) in the acidic environment induced by Enterobacter sp. It indicated a decreasing tendency of crystallite size (from ∼400 nm to 10–20 nm) during gradual incorporation of carbonate (from 2.5 to 13.8 wt %). Meanwhile, the shape of CHAp crystals was transformed from elongated to plate‐like. Addition of Enterobacter sp. enhanced P release from CHAp (especially for the CHAp with ∼8 wt % CO3) around 10 times. Moreover, the bacterium provided a moderately acidic environment to cause more formation of stable pyromorphite over other Pb‐minerals, for example, Pb3(PO4)2, and PbCO3. Then, transmission electron microscopy‐energy dispersive X‐Ray spectroscopy mapping successfully confirmed the Pb labeling on the newly formed phosphate mineral as Pb (with high‐atomic weight) has strong signal under electron microscopy. This study therefore elucidated that Pb labeling has a bright future to explore the degradation of tooth mineral by microorganisms, as well as to evaluate the resistance of calcium phosphate dental restorative materials. [ABSTRACT FROM AUTHOR]

Summary: Successful application of microorganisms to heavy metal remediation depends on their resistance to toxic metals. This study contrasted the differences of tolerant mechanisms between Pb2+ and Cd2+ in Enterobacter sp. Microbial respiration and production of formic acid showed that Enterobacter sp. had a higher tolerant concentration of Pb (>1000 mg l−1) than Cd (about 200 mg l−1). Additionally, SEM confirmed that most of Pb and Cd nanoparticles (NPs) were adsorbed onto cell membrane. The Cd stress, even at low concentration (50 mg l−1), significantly enlarged the sizes of cells. The cellular size raised from 0.4 × 1.0 to 0.9 × 1.6 μm on average, inducing a platelet‐like shape. In contrast, Pb cations did not stimulate such enlargement even up to 1000 mg l−1. Moreover, Cd NPs were adsorbed homogeneously by almost all the bacterial cells under TEM. However, only a few cells work as 'hot spots' on the sorption of Pb NPs. The heterogeneous sorption might result from a 'self‐sacrifice' mechanism, i.e., some cells at a special life stage contributed mostly to Pb sorption. This mechanism, together with the lower mobility of Pb cations, caused higher microbial tolerance and removal efficiency towards Pb2+. This study sheds evident contrasts of bacterial resistance to the two most common heavy metals. [ABSTRACT FROM AUTHOR]

Summary: Environmental microorganisms have been widely applied in heavy metal remediation. This study explored the mechanisms of lead tolerance of two typical filamentous fungi, Aspergillus niger and Penicillium oxalicum. It is shown that the mechanisms of reducing Pb toxicity by these two fungi have three major pathways. The secreted oxalic acid can react with Pb (II) to form insoluble Pb minerals, primarily lead oxalate. Then, the enhanced biosorption via forming new border of cell wall prevents the transportation of Pb (II) into hypha. In addition, the fungal activity could be maintained even at high Pb concentration due to the intracellular accumulation. It was confirmed that A. niger has the higher Pb tolerance (up to 1500 mg l−1 Pb level) compared with P. oxalicum (up to 1000 mg l−1). Meanwhile, Pb levels below 1000 mg l−1 partially stimulate the bioactivity of A. niger, which was confirmed by its elevated respiration (from 53 to 63 mg C l−1 medium h−1). This subsequently enhanced microbial functions of A. niger to resist Pb toxicity. A better understanding of Pb tolerance of these two fungi sheds a bright future of applying them to remediate lead‐contaminated environments. [ABSTRACT FROM AUTHOR]

This study proposed a novel system for recognising emotional content in music, and the proposed system is based on particle swarm optimisation (PSO)‐based fuzzy hyper‐rectangular composite neural networks (PFHRCNNs), which integrates three computational intelligence tools, i.e. hyper‐rectangular composite neural networks (HRCNNs), fuzzy systems, and PSO. PFHRCNN is flexible to the complex data due to the fuzzy membership estimation, and an optimisation of the parameters is provided by PSO. First, raw features are extracted from each music clips. After feature extraction, a HRCNN is separately constructed for each class. Each trained HRCNN will result in a set of crisp rules. A problem associated with these generated crisp rules is that some of them are ineffective; therefore, a crisp rule is transformed into a fuzzy rule incorporated with a confidence factor. Next, PSO is adopted to simultaneously trim the rules, search a set of good confidence factors, and fine‐tune the locations of the selected hyper‐rectangles to increase their effectiveness. Finally, a PFHRCNN consisted of a set of fuzzy rules can be generated to recognise the emotion state of music. The experimental result shows that the proposed system has a good performance. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSNs) have been widely evaluated for their potential use as carriers for cancer diagnosis and therapy. Understanding the toxicity of MSNs is crucial to their biomedical applications. Although several groups have reported the cytotoxicity of MSNs, the genotoxicity (inducing genetic aberrations) of MSNs in normal human cells has not been extensively investigated. Gene amplification and mutation may initiate and promote carcinogenesis, and changes in mRNA expression can affect normal human physical functions. In this study, human embryonic kidney 293 (HEK293) cells were treated overnight with MSNs at a concentration of 120 µg/mL. The cells were assayed with fluorescent in situ hybridization to check for chromosome changes and gene amplification. Mutations in the epidermal growth factor receptor 1 ( EGFR1) and KRAS genes were checked with DNA sequencing. The effects of MSNs on mRNA expression were investigated with an Agilent human mRNA microarray. No chromosomal alterations or gene mutations in EGFR or KRAS were observed in the control HEK293 cells or HEK293 cells exposed to MSNs. The microarray analysis showed that MSNs significantly altered gene expression. The expression of 579 genes was upregulated and that of 1263 genes was downregulated in HEK293 cells treated with MSNs compared with the control HEK293 cells. Our findings suggest that exposure to MSNs is genotoxic to normal human cells, leading to changes in the expression of some genes. This genotoxicity may cause cellular dysfunction and certain benign diseases. We have not shown that MSN exposure induces serious genotoxicity involving carcinogenesis. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Software avatars are increasingly applied to support children's collaborative storytelling because avatars may serve as a transparent shield or as embodied agents to facilitate creativity in children. However, when using avatars, it is not easy for children to practise and refine their speaking skills by narrating their stories to an audience. The programming difficulties involved in that process tend to distract attention away from the collaborative storytelling activity itself. This study therefore proposes an interaction model featuring tangible story avatars (TSAs) that can serve as a platform to scaffold collaborative story creation, revision and narrative. A 9-week study with 16 children aged 8 years was conducted to evaluate the interaction model with the TSAs. The results suggest that the TSAs may play three primary roles in facilitating collaborative storytelling: as a tool for developing confidence, as a tool for reflective story development and as a group artefact. Researchers and educators may find it valuable to consider these three roles in designing the TSAs in support of collaborative storytelling in similar contexts. [ABSTRACT FROM AUTHOR]

A rare case of rapidly growing osteosarcoma that developed in the uterine corpus of a 62-year-old woman is presented. The tumor occupied almost the entire pelvic cavity and extended into the abdominal cavity, with marked involvement of the intestines. Histopathologically, the tumor was composed of an osteoblastic component, accompanied by conspicuous bone formation, and a fibroblastic component. The tumor cells were positive for vimentin and osteocalcin, as well as desmin, α-smooth muscle actin and muscle-specific actin, but negative for h-caldesmon. The results indicated myofibroblastic differentiation in a part of the tumor. A review of 14 reported cases and our case of uterine osteosarcoma revealed that this tumor has a biologically aggressive nature, although its histopathological and immunohistochemical features are similar to those of osteosarcomas in soft tissue and bone. As the prognosis of patients with this tumor is poor, it is of importance to differentiate this tumor from other types of tumors arising from the uterine corpus. [ABSTRACT FROM AUTHOR]

Mild hypothermia is considered to have a protective effect during ischemic neuronal cell death. The present study provides experimental evidence for this beneficial role of mild hypothermia using reversible middle cerebral artery occlusion (MCAo) in a Sprague–Dawley (SD) rat model. MCAo was induced in rats for 1 h followed by reperfusion at different periods. Hematoxylin–eosin (HE) staining in normothermic (NT) 37°C and hypothermic (HT) 33°C groups of rats confirmed cerebral infarcts. The mean per cent infarct area was significantly reduced in the HT group of rats. Immunohistochemical analysis was done using anti-Fas and caspase-3 antibodies. The immunohistochemical expression of Fas and caspase-3 was demonstrable as early as 5 h after reperfusion, but the expression pattern maximized at 24 h after reperfusion. The expression of Fas and caspase-3 proteins showed a clear decrease in the HT group over the NT group. In situ detection of DNA fragmentation was done using the terminal deoxy-nucleotidyl transferase-mediated dUTP-biotin nick end- labeling method (TUNEL). TUNEL-positive cells were first observed at 5 h after reperfusion and progressively increased by 24 h. A higher number of TUNEL-positive cells was found in the NT group, but they were significantly decreased in the HT group. Further, DNA fragmentation was confirmed by size fractionation in agarose gel. These findings demonstrate a positive relation between the expression of Fas, caspase-3 and TUNEL-positive cells. Mild expression of Fas and caspase-3 proteins and a reduced number of TUNEL-positive cells in the HT group is clear evidence for the protective role of hypothermia in ischemia-induced cell death. [ABSTRACT FROM AUTHOR]

The article focuses on the study of Dinesh Rakheja and colleagues related to the incidence of isocitrate dehydrogenase (IDH) mutations in acute myeloid leukemia (AML) with cuplike nuclei. It mentions that the study is undertaken through a review of Wright-Giemsa-stained peripheral blood, hematoxylin-eosin-stained bone marrow dot, and bone marrow aspirate smears. The results of the study show that IDH mutations is associated with outcome in AML patients.

Objective: People with chronic vestibular dysfunction can be treated with balance rehabilitation. Virtual reality (VR) technology may serve as a useful therapeutic tool to facilitate rehabilitation. The aim of this pilot study was to investigate the clinical applicability of VR technology in treating patients with vestibular dysfunction. Method: Five patients with chronic vestibular dysfunction were recruited for this uncontrolled clinical study. The rehabilitation protocol (modified Cawthorne‐Cooksey exercises, MCCE) was adapted into a VR‐based training system. Patients followed the instructions of MCCE to complete 20 sessions of vestibular rehabilitation within a 4‐week period. Results: A VR‐based rehabilitation system was developed with various latest technologies, including Kinect Xbox for full‐body interaction, 3D‐ready projector with shutter‐glasses for stereo imaging, Wii Fit pressure pad for tracing the center of gravity, and Unity game engine for leveled‐difficulty design. Five VR tasks were built, and more than 100 training trials were designed. Subjectively, all patients experienced the improvement of balance function performing daily activities and were overall positive to the training protocol. After intervention the fast component of postural sway (P <. 05) was reduced. The follow‐up interview showed decreased disability and increased general health. Conclusion: VR has many advantages over traditional rehabilitation techniques in improving the testing or training environment of human performance. This study demonstrates that VR technology offers great promise in the field of vestibular rehabilitation. [ABSTRACT FROM AUTHOR]