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Bond of nanoinclusions reinforced concrete with old concrete: strength, reinforcing mechanisms and prediction model
Get PDFYesThis paper investigated the bond strength of eight nanoinclusions reinforced concrete with old concrete through a splitting tensile test. The reinforcing mechanisms of bond due to nanoinclusion was also explored by means of scanning electron microscope and energy dispersive spectrometer. A prediction model for the bond strength between nanoinclusion reinforced concrete with old concrete substrate was developed and calibrated against the experimental results obtained. The experimental results indicated that bond strength between nanoinclusions reinforced concrete and old concrete can reach 2.85 MPa, which is 0.8 MPa/39.0% higher than that between new concrete without nanoinclusions and old concrete. The reinforcing mechanisms can be attributed to the enrichment of nanoinclusions in the new-to-old concrete interface, compacting the interfacial microstructures and connecting hydration products in micropores of old concrete with that in bulk new concrete. In addition, the prediction model proposed on the basis of reinforcing mechanisms can accurately describe the relationship of the nanoinclusion content and the bond strength of nanoinclusions reinforced concrete with old concrete
The effects of knowledge integration and contextual ambidexterity on innovation in entrepreneurial ventures
Get PDFYesThis paper utilizes insights from the knowledge-based view and ambidexterity literature to examine the effects of knowledge integration (KI) on innovation via contextual ambidexterity (CA). The paper also investigates the potential moderating role of human resource (HR) slack on the relationship between KI and CA. Using survey data collected from 245 entrepreneurial firms operating in Ghana, the findings show that KI positively relates to CA, and this relationship is moderated by HR slack. In addition, we observed that CA mediates KI and innovation. The broader theoretical and practical implications of the study are outlined
Progress towards a clinically-successful ATR inhibitor for cancer therapy
Get PDFYesThe DNA damage response (DDR) is now known to play an important role in both cancer development and its treatment. Targeting proteins such as ATR (Ataxia telangiectasia mutated and Rad3-related) kinase, a major regulator of DDR, has demonstrated significant therapeutic potential in cancer treatment, with ATR inhibitors having shown anti-tumour activity not just monotherapies, but also in potentiating the effects of conventional chemotherapy, radiotherapy, and immunotherapy. This review focuses on the biology of ATR, its functional role in cancer development and treatment, and the rationale behind inhibition of this target as a therapeutic approach, including evaluation of the progress and current status of development of potent and specific ATR inhibitors that have emerged in recent decades. The current applications of these inhibitors both in preclinical and clinical studies either as single agents or in combinations with chemotherapy, radiotherapy and immunotherapy are also extensively discussed. This review concludes with some insights into the various concerns raised or observed with ATR inhibition in both the preclinical and clinical settings, with some suggested solutions
Developing supportive local communities: Perspectives from people with dementia participating in the IDEAL programme
No full textYesCommunities play an important role in supporting people living with affected by dementia. The aim of this study was to explore what could be changed in the local community to enable those with dementia to live well. People with dementia and carers taking part in the IDEAL programme responded to open-ended questions. Responses from 1,172 people with dementia and 702 caregivers were analysed using thematic analysis. Four themes were identified: raising awareness, improving access to support services, providing social events and activities, and supporting people to engage in the community. These highlight the role of individuals, resources and the environment in supporting those with dementia. Longer-term investment in services is needed to underpin dementia-inclusive communities.The IDEAL study was funded jointly by the Economic and Social Research Council (ESRC) and the National Institute for Health Research (NIHR) through grant ES/L001853/2. The IDEAL-2 study’ is funded by Alzheimer’s Society, grant number 348, AS-PR2-16-001. The support of ESRC, NIHR and Alzheimer’s Society is gratefully acknowledged
Comparative Techno-Economic Analysis of Carbon Capture Processes: Pre-Combustion, Post-Combustion, and Oxy-Fuel Combustion Operations
Get PDFYesEvaluation of economic aspects is one of the main milestones that affect taking rapid actions in dealing with GHGs mitigation; in particular, avoiding CO2 emissions from large source points, such as power plants. In the present study, three kinds of capturing solutions for coal power plants as the most common source of electricity generation have been studied from technical and economic standpoints. Aspen HYSYS (ver.11) has been used to simulate the overall processes, calculate the battery limit, and assess required equipment. The Taylor scoring method has been utilized to calculate the costliness indexes, assessing the capital and investment costs of a 230 MW power plant using anthracite coal with and without post-combustion, pre-combustion, and oxy-fuel combustion CO2 capture technologies. Comparing the costs and the levelized cost of electricity, it was found that pre-combustion is more costly, to the extent that the total investment for it is approximately 1.6 times higher than the oxy-fuel process. Finally, post-combustion, in terms of maturity and cost-effectiveness, seems to be more attractive, since the capital cost and indirect costs are less. Most importantly, this can be applied to the existing plants without major disruption to the current operation of the plants
Die US-Intervention in Afghanistan: Die Politik der Obama-Regierung
Get PDFYesThis contribution discusses the national security objectives and the political parameters of the Obama administration’s decision to shift towards a counterinsurgency strategy and increase troop levels in Afghanistan. On the basis of the key strategic documents that formed the basis of the interagency process, as well as the political constraints under which the Obama administration was operating, it is possible to understand the key factors that defined the policy. The article also explain the various contradictions between the geopolitical context, the strategic objectives as defined by Obama and means to achieve them. On the basis of such analysis it is clear that the policy could at best achieve a partial success
Determinants of Intellectual Capital Disclosure and its Impacts on Audit Effort and Analyst Forecast Accuracy: UK Evidence
Get PDFStructural changes in the knowledge economy have greatly affected the way business
is conducted and the processes firms create value. The financial reporting system is
inadequate as a result of such changes, and disclosure of intellectual capital (IC)
information has gained importance for communicating with capital markets. Empirical
research documents corporate governance (CG) factors influencing IC disclosure
practices, as well as demonstrates the value-relevance and predictive power of IC
information.
The disclosure of IC information by listed firms is a topic that has attracted
considerable attention from contemporary researchers, but scant empirical evidence
exists. Much of the researchers has examined CG as a key determinant of IC (and
nonfinancial) disclosure; in contrast, few provides evidence for explaining their
controversial findings of board independence on disclosure. In addition, a lack of
studies confirms the literature about the use of IC information by capital market
participants. Therefore, this thesis aims to examine disclosure of IC information in
relation to outside directors, auditors, and sell-side analysts respectively.
The specific objectives of this thesis are to examine whether outside directors’
expertise is a determinant of IC disclosure; and the extent to which the disclosure of
IC information impacts on audit effort and analysts’ forecasts. In order to address these research objectives, a content analysis of IC disclosure (a self-constructed index of 64
coded items) in strategic reports released by FTST 350 companies is used. The
content analysis captures and measures IC disclosure by category (i.e., human,
structural & relational capital), notion (i.e., static vs. dynamic), and connection (i.e.,
across categories vs. with strategies). Using multivariate regression models that were
primarily developed upon information asymmetry arguments and agency theory, the
specific objectives of this thesis are addressed in three empirical chapters.
The findings in Chapter 3 showed that proportion of outside directors (NEDs) with
cross-directorship, nonaccounting and academia expertise has a positive association
with IC disclosures, whereas board independence itself has no effect on the
disclosures. The findings indicates that the monitoring role of NEDs alone is
inadequate in promoting IC disclosure. Rather, it supports the importance of the dual
role (i.e., monitor and advisory) of a supervisory board. The results also respond to
the UK CG Code in their recommendation that the combination of skills, experience
and knowledge guarantees a sound information environment to the market.
Nonetheless, findings raised a further concern about the quantity of IC disclosures
when companies have more NEDs with accounting expertise.
On whether and how disclosure of IC information impacts on audit effort, Chapter 4
found that firms with high levels of IC disclosure in the previous year pay more audit
fees (proxied for audit effort) in the current year regardless of their earnings quality
conditions. It was also found that firms greatly disclosing dynamic IC information are
charged more than those of focusing on static IC disclosure. In addition, findings in
Chapter 5 revealed that there is a negative relation between IC disclosure and analyst
forecast errors, indicating that UK sell-side analysts appreciate the disclosure of IC
information and thus confirming that IC information has predictive ability of explaining a firm’s future value. It was further identified that disclosed IC information absorbs the
negative effect of concentrated executive ownership and opaque financial
environment.
Overall, the results of this thesis suggest that IC reporting process could be improved
by having sufficient outside directors with certain types of expertise on the board. In
doing so, improved IC disclosure helps to reduce information asymmetry (proxied by
analyst forecast accuracy) between firms and outside investors, albeit firms bear a
significant increase in audit fees. This study calls for guidelines for IC disclosure in the
UK and the support of assurance services to enhance credibility of firm-provided IC
information in a bid to promote the communication of IC information with the capital
market
Compressive properties and underlying mechanisms of nickel coated carbon nanotubes modified concrete
No full textNoNickel coated multi-walled carbon nanotubes (Ni-MWCNTs) having exceptional mechanical properties, thermal conductivity and dispersibility can effectively overlap in cementitious matrix, thus forming an enhanced and thermal conductive network. They are therefore a promising nanofiller for modifying cement and concrete materials. This paper studies the compressive properties of reactive powder concrete (RPC) filled with different aspect ratios of Ni-MWCNTs, including strength, toughness, Young's modulus and Poisson's ratio. It is concluded that the incorporation of 0.06 vol.% Ni-MWCNTs with an aspect ratio of 1500 maximally increases the compressive strength and toughness of RPC by 20.24%/20.39 MPa and 43.89%/56.35 (N·m), respectively. However, Young's modulus and Poisson's ratio of Ni-MWCNTs modified composites do not significantly be improved. Besides, a constitutive model of Ni-MWCNTs reinforced RPC under uniaxial compression is established based on the continuum damage mechanics theory, reasonably predicting the relationship between compressive strength and deformation of composites. The modification mechanism of Ni-MWCNTs is also investigated through the temperature distribution monitoring inside composites, Scanning Electron Microscope (SEM) observation and energy dispersive x-ray spectrometry (EDS) analysis of Ni-MWCNTs reinforced RPC. The thermal conductive network formed by Ni-MWCNTs in matrix reduces the temperature difference and improves the temperature uniformity inside composites, thereby decreasing thermal stresses, primary cracks and defects of composites. Furthermore, the incorporation of Ni-MWCNTs makes the RPC microstructures dense, decreases the average CaO to SiO2 ratio, and inhibits the development of cracks inside RPC, thus achieving effective enhancement to RPC.National Science Foundation of China (52178188, 51978127 and 51908103), and the Fundamental Research Funds for the Central Universities (DUT21RC(3)039)
Phenotypic differences between microvascular and macrovascular smooth muscle cells and their contribution to coronary microvascular dysfunction
Get PDFYesCoronary microvascular dysfunction (CMD) is an under-diagnosed condition characterized by functional alteration of the small coronary arterioles and the cardiac capillary bed. The vessels do not dilate appropriately in response to changes in cardiac oxygen demand, leading to chest pain and symptoms of angina. These blood vessels contain two major cell types: the endothelial cells, which line the blood vessels and detect changes in oxygen demand, and smooth muscle cells (SMC) which respond to these changes by contracting or relaxing to provide an optimal blood supply to the cardiac tissue. Many CMD studies have focused on the endothelial cells as these cells secrete vasorelaxants and vasoconstrictors. However, comparably fewer studies have examined SMC despite their functional role in contracting and relaxing. A variety of health conditions and lifestyle choices, such as diabetes, hypertension and cigarette smoking, can promote the development of both CMD and macrovascular coronary artery disease; a condition where SMC have been studied extensively. This review article will consider the influence of CMD on SMC phenotype. It will discuss the structural, cellular and molecular changes in CMD, and will summarise how co-morbidities can have differing effects on micro- and macro-vascular SMC phenotype and function, which complicates the development of new therapeutic avenues for CMD
Impacts of dried Athel leaves and silica fume as eco-friendly wastes on behaviour of lime-treated heavy clay
No full textConstruction on problematic soils is challenging owing to the potential of volume changes due to
variation of moisture content. Lime stabilisation can be used to treat problematic soils. The main
drawbacks of lime addition to the clayey soils are the need for lengthy curing periods and
relatively large quantities of lime for significant improvement and also loss in ductility. Using
eco-friendly agricultural and industrial wastes, that can partially be substituted by the material
responsible for greenhouse gases such as lime, can overcome these drawbacks and decrease global
warming. In the current study, variables controlling the unconfined compressive strength of lime
treated clay with a focus on assessing the effects of moisture content were investigated.
Furthermore, the effects of adding agricultural waste (Dried Athel Leaves (DAL)) and industrial
waste (Silica Fume (SF)) on hydromechanical properties of lime treated clay were assessed. The
performance of the treated mixtures was examined based on results attained from unconfined
compressive strength, swelling pressure and permeability. Specimens were treated with deferent
percentages of lime and cured at different periods and temperatures to observe the strength
behaviour. In oedometer tests, the specimens were prepared and tested immediately after compaction.
The failure patterns were also studied to better understand the ultimate behaviour of lime
stabilised clays. The appearance and presence of cementitious products were identified by using the
scanning electron microscope and energy dispersive X-ray spectrometer techniques to elucidate their
strength development.
The findings indicated that the effect of moisture content is controlled by the clay content and
unit weight. The addition of 7% lime to clay caused a remarkable increase in the unconfined
compressive strength by 363%. The incorporation of
2% DAL and 5% SF within lime treated clay further increased the strength by 6% and 33% respectively
after curing of 28 days at 20 °c in comparison with those attained by lime treatment only. The improvement of the strength of the lime treated clay augmented with both wastes continued in long term. Temperature and lime content have positive effects on the improvement of strength, however, increasing lime content to 11% negatively affected the strength of lime treated specimens with 2% DAL. The formation of cementitious products was observed in SEM images and detected quantitatively through EDS analysis.
The results of the recorded oedometric tests for lime-DAL and lime-SF mixtures revealed that
incorporation of the 2% DAL and 5% SF reduced the clay swelling pressures by 25% and 10% compared
to that attained by lime treatment only resulting in total reductions of 93.6% and 68% from that
recorded on untreated clay. In addition, the impermeable clay transformed into permeable material
by adding DAL and SF. Of the two types of wastes considered in this research, DAL demonstrated more
superior improving capability. A further study was conducted to develop ANN model based on collated
laboratory data for the prediction of the UCS values of lime treated soils. The promising outcomes
of this research suggest that the drawbacks of lime stabilisation can be overcome by the addition
of agricultural and industrial wastes. Consequently, the findings attained could be considered in
future practice standards with regards to the requirement of lime stabilisation.Ministry of Higher Education and Scientific Research in Liby