403 research outputs found
Analysis of carbon dioxide bands near 2.2 micrometers
Carbon dioxide is one of the more important atmospheric infrared-absorbing gases due to its relatively high, and increasing, concentration. The spectral parameters of its bands are required for understanding radiative heat transfer in the atmosphere. The line intensities, positions, line half-widths, rotational constants, and band centers of three overlapping bands of CO2 near 2.2 microns are presented. Non-linear least squares (NLLS) regression procedures were employed to determine these parameters
Microstructure, Elastic and Inelastic Properties of Partially Graphitized Biomorphic Carbons
The microstructural characteristics and amplitude dependences of the Young’s modulus E and
internal friction (logarithmic decrement δ) of biocarbon matrices prepared by beech wood carbonization at
temperatures Tcarb = 850–1600°C in the presence of a nickelcontaining catalyst have been studied. Using
Xray diffraction and electron microscopy, it has been shown that the use of a nickel catalyst during carbon
ization results in a partial graphitization of biocarbons at Tcarb ≥ 1000°C: the graphite phase is formed as 50
to 100nm globules at Tcarb = 1000°C and as 0.5 to 3.0μm globules at Tcarb = 1600°C. It has been found that
the measured dependences E(Tcarb) and δ(Tcarb) contain three characteristic ranges of variations in the
Young’s modulus and logarithmic decrement with a change in the carbonization temperature: E increases and
δ decreases in the ranges Tcarb 1300°C; in the range 1000 < Tcarb < 1300°C, E sharply
decreases and δ increases. The observed behavior of E(Tcarb) and δ(Tcarb) for biocarbons carbonized in the
presence of nickel correlates with the evolution of their microstructure. The largest values of E are obtained
for samples with Tcarb = 1000 and 1600°C. However, the samples with Tcarb = 1600°C exhibit a higher suscep
tibility to microplasticity due to the presence of a globular graphite phase that is significantly larger in size and
total volume.Peer reviewe
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A narrative inquiry into the identity formation of Chinese doctoral students in relation to study abroad
The present study explores a topic which has been under-studied to date, namely the identity formation of Chinese PhD students in relation to study abroad. Underpinned by Giddens' (1991) "reflexive project of the self", which privileges agency and reflexivity, and using a narrative inquiry approach, it presents four students' 'stories' collected through semi-structured interviews and focus group discussions in the form of a trajectory of development fro past to future. In building a picture of theways in which students' self-identity is shaped by and shapes their experience of study abroad, the stories illustrate individual agency, motivation, self-determination and reflexivity. In doing so, they challenge the essentialised view of Chinese students as a homogeneous and sometimes problematic group and point to implications for action by the host institutions
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Chinese overseas doctoral student narratives of intercultural adaptation
This study aims to explore how Chinese overseas doctoral students adjust to a different academic, social and cultural environment, using Giddens’ theoretical framework of self-identity (1991). The findings indicate the participants proactively used various coping strategies in meeting challenges, and adapting to new social environments. Continuity and stability of self-identity were achieved either culturally or academically through self-reflexivity, autonomy, creativity, authenticity, and reliance on an ontological identity. The result is to challenge the grand narrative of essentialised “problematic Chinese learners”
Short-Term Effects of Biogas Digestates and Pig Slurry Application on Soil Microbial Activity
The effect of four biogas digestates (BD-A, BD-B, BD-C, and BD-D) and pig slurry (PS) on soil microbial functions was assessed at application rates corresponding to 0–1120 kg NH4+-N ha−1. At dose corresponding to 140 kg NH4+-N ha−1, 30.9–32.5% of the carbon applied in BD-A, BD-C, and PS was utilized during 12 days, while for BD-B and BD-D corresponding utilization was 19.0 and 16.9%, respectively. All BDs resulted in net nitrogen assimilation at low rates (17.5–140 kg NH4+-N ha−1) but net mineralization dominated at higher rates. PS resulted in net mineralization at all application rates. All residues inhibited potential ammonium oxidation (PAO), with EC50-values ranging between 45 and 302 kg NH4+-N ha−1. Low rates of BDs appeared to weakly stimulate potential denitrification activity (PDA), while higher rates resulted in logarithmic decrease. The EC50-values for PDA were between 238 and 347 kg NH4+-N ha−1. No inhibition of PDA was observed after amendment with PS. In conclusion, biogas digestates inhibited ammonia oxidation and denitrification, which could be an early warning of potential hazardous substances in the digestates. However, this effect can also be regarded as positive, since it may reduce nitrogen losses
Using Artificial Neural Network as an Approach to Analyze People Sentiment Level Based on Social Media Data
The internet has become an essential online communication tool for many people today. For a variety of reasons, many researches have been done lately in the field of Artificial Neural Network (ANN) considering people sentiments based on social media data. This analytical study conducted to analyze happiness of Libyan people based on twitter data sets.
Matlab used in this study to code around 1,000 status/comments data. Processing consists of five processes, namely cleansing, Tokenization, case folding, removal stop word, and stemming. The study represents Artificial Neural Network model for the mining of Twitter opinions using an Artificial Neural Network model approach for the abstracting and visualization scheme of Twitter feeds and a classification and prediction approach. This study presented a contribution in the form of proposing a new visualization model for Twitter mood prediction based on the ANN approach
Expression of auxin-binding protein1 during plum fruit ontogeny supports the potential role of auxin in initiating and enhancing climacteric ripening
Auxin-binding protein1 (ABP1) is an active element involved in auxin signaling and plays critical roles in auxin-mediated plant development. Here, we report the isolation and characterization of a putative sequence from Prunus salicina L., designated PslABP1. The expected protein exhibits a similar molecular structure to that of well-characterized maize-ABP1; however, PslABP1 displays more sequence polarity in the active-binding site due to substitution of some crucial amino-acid residues predicted to be involved in auxin-binding. Further, PslABP1 expression was assessed throughout fruit ontogeny to determine its role in fruit development. Comparing the expression data with the physiological aspects that characterize fruit-development stages indicates that PslABP1 up-regulation is usually associated with the signature events that are triggered in an auxin-dependent manner such as floral induction, fruit initiation, embryogenesis, and cell division and elongation. However, the diversity in PslABP1 expression profile during the ripening process of early and late plum cultivars seems to be due to the variability of endogenous auxin levels among the two cultivars, which consequently can change the levels of autocatalytic ethylene available for the fruit to co-ordinate ripening. The effect of auxin on stimulating ethylene production and in regulating PslABP1 was investigated. Our data suggest that auxin is involved in the transition of the mature green fruit into the ripening phase and in enhancing the ripening process in both auxin- and ethylene-dependent manners thereafter
Inhibition of the JAK2/STAT3 pathway in ovarian cancer results in the loss of cancer stem cell-like characteristics and a reduced tumor burden
Background Current treatment of ovarian cancer patients with chemotherapy leaves behind a residual tumor which results in recurrent ovarian cancer within a short time frame. We have previously demonstrated that a single short-term treatment of ovarian cancer cells with chemotherapy in vitro resulted in a cancer stem cell (CSC)-like enriched residual population which generated significantly greater tumor burden compared to the tumor burden generated by control untreated cells. In this report we looked at the mechanisms of the enrichment of CSC-like residual cells in response to paclitaxel treatment. Methods The mechanism of survival of paclitaxel-treated residual cells at a growth inhibitory concentration of 50% (GI50) was determined on isolated tumor cells from the ascites of recurrent ovarian cancer patients and HEY ovarian cancer cell line by in vitro assays and in a mouse xenograft model. Results Treatment of isolated tumor cells from the ascites of ovarian cancer patients and HEY ovarian cancer cell line with paclitaxel resulted in a CSC-like residual population which coincided with the activation of Janus activated kinase 2 (JAK2) and signal transducer and activation of transcription 3 (STAT3) pathway in paclitaxel surviving cells. Both paclitaxel-induced JAK2/STAT3 activation and CSC-like characteristics were inhibited by a low dose JAK2-specific small molecule inhibitor CYT387 (1 μM) in vitro. Subsequent, in vivo transplantation of paclitaxel and CYT387-treated HEY cells in mice resulted in a significantly reduced tumor burden compared to that seen with paclitaxel only-treated transplanted cells. In vitro analysis of tumor xenografts at protein and mRNA levels demonstrated a loss of CSC-like markers and CA125 expression in paclitaxel and CYT387-treated cell-derived xenografts, compared to paclitaxel only-treated cell-derived xenografts. These results were consistent with significantly reduced activation of JAK2 and STAT3 in paclitaxel and CYT387-treated cell-derived xenografts compared to paclitaxel only-treated cell derived xenografts. Conclusions This proof of principle study demonstrates that inhibition of the JAK2/STAT3 pathway by the addition of CYT387 suppresses the ‘stemness’ profile in chemotherapy-treated residual cells in vitro, which is replicated in vivo, leading to a reduced tumor burden. These findings have important implications for ovarian cancer patients who are treated with taxane and/or platinum-based therapies. Keywords: Ovarian carcinoma, Cancer stem cell, Metastasis, Ascites, Chemoresistance, Recurrence, JAK2/STAT3 pathwa
SPARC 2017 retrospect & prospects : Salford postgraduate annual research conference book of abstracts
Welcome to the Book of Abstracts for the 2017 SPARC conference. This year we not only celebrate the work of our PGRs but also the 50th anniversary of Salford as a University, which makes this year’s conference extra special. Once again we have received a tremendous contribution from our postgraduate research community; with over 130 presenters, the conference truly showcases a vibrant PGR community at Salford. These abstracts provide a taster of the research strengths of their works, and provide delegates with a reference point for networking and initiating critical debate. With such wide-ranging topics being showcased, we encourage you to exploit this great opportunity to engage with researchers working in different subject areas to your own. To meet global challenges, high impact research inevitably requires interdisciplinary collaboration. This is recognised by all major research funders. Therefore engaging with the work of others and forging collaborations across subject areas is an essential skill for the next generation of researchers
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