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Performance evaluation of masonry grout containing high volume of palm oil industry by-products
No full textThe rapid depletion of natural resources has led to the need to develop sustainable practices and material in various applications. One such sustainable practice is to divert the waste generated in the palm oil industry into production of building materials. In this study, palm oil clinker (POC) is used to replace cement and coarse aggregate. The POC chunks are crushed to be used as coarse aggregate and further ground to produce POC powder (POCP) to be used as a binder. The physical properties, chemical composition and scanning electronic microscopic studies were conducted to check the feasibility of substitution of up to 50% POCP as binder and up to 100% POC as coarse aggregate. Density, ultrsonic pulse velocity(UPV), compressive strength for air & water curing, flexural, tensile strength, modulus of elasticity in water cured regimes and structural efficiency were evaluated for the samples. Carbon footprint, cost effieciency and energy savings were also evaluated to understand the contribution of POC to sustainability. The results revealed that the ideal mixture of GPP (30% POCP & 50% POC) masonry grout achieved 79% of compressive strength, a 83% of flexural strength, 85% of tensile strength and about 85.5% of modulus elasticity, as compared to control masonry grout. Carbon emissions of GPP was reduced by 21% and 14.60% cost reduction was established, in addition, appreciable energy savings was notified. The study showed that that utilisation of POC as eco-friendly material in masonry grout is highly recommended based on performance and can provide a route to sustanable practices in the building industry. © 2019 Elsevier Lt
Collagen Induces a More Proliferative, Migratory and Chemoresistant Phenotype in Head and Neck Cancer via DDR1
Get PDFHead and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and includes squamous cell carcinomas of the oropharynx and oral cavity. Patient prognosis has remained poor for decades and molecular targeted therapies are not in routine use. Here we showed that the overall expression of collagen subunit genes was higher in cancer-associated fibroblasts (CAFs) than normal fibroblasts. Focusing on collagen8A1 and collagen11A1, we showed that collagen is produced by both CAFs and tumour cells, indicating that HNSCCs are collagen-rich environments. We then focused on discoidin domain receptor 1 (DDR1), a collagen-activated receptor tyrosine kinase, and showed that it is over-expressed in HNSCC tissues. Further, we demonstrated that collagen promoted the proliferation and migration of HNSCC cells and attenuated the apoptotic response to cisplatin. Knockdown of DDR1 in HNSCC cells demonstrated that these tumour-promoting effects of collagen are mediated by DDR1. Our data suggest that specific inhibitors of DDR1 might provide novel therapeutic opportunities to treat HNSCC
Machine learning methods for better water quality prediction
No full textIn any aquatic system analysis, the modelling water quality parameters are of considerable significance. The traditional modelling methodologies are dependent on datasets that involve large amount of unknown or unspecified input data and generally consist of time-consuming processes. The implementation of artificial intelligence (AI) leads to a flexible mathematical structure that has the capability to identify non-linear and complex relationships between input and output data. There has been a major degradation of the Johor River Basin because of several developmental and human activities. Therefore, setting up of a water quality prediction model for better water resource management is of critical importance and will serve as a powerful tool. The different modelling approaches that have been implemented include: Adaptive Neuro-Fuzzy Inference System (ANFIS), Radial Basis Function Neural Networks (RBF-ANN), and Multi-Layer Perceptron Neural Networks (MLP-ANN). However, data obtained from monitoring stations and experiments are possibly polluted by noise signals as a result of random and systematic errors. Due to the presence of noise in the data, it is relatively difficult to make an accurate prediction. Hence, a Neuro-Fuzzy Inference System (WDT-ANFIS) based augmented wavelet de-noising technique has been recommended that depends on historical data of the water quality parameter. In the domain of interests, the water quality parameters primarily include ammoniacal nitrogen (AN), suspended solid (SS) and pH. In order to evaluate the impacts on the model, three evaluation techniques or assessment processes have been used. The first assessment process is dependent on the partitioning of the neural network connection weights that ascertains the significance of every input parameter in the network. On the other hand, the second and third assessment processes ascertain the most effectual input that has the potential to construct the models using a single and a combination of parameters, respectively. During these processes, two scenarios were introduced: Scenario 1 and Scenario 2. Scenario 1 constructs a prediction model for water quality parameters at every station, while Scenario 2 develops a prediction model on the basis of the value of the same parameter at the previous station (upstream). Both the scenarios are based on the value of the twelve input parameters. The field data from 2009 to 2010 was used to validate WDT-ANFIS. The WDT-ANFIS model exhibited a significant improvement in predicting accuracy for all the water quality parameters and outperformed all the recommended models. Also, the performance of Scenario 2 was observed to be more adequate than Scenario 1, with substantial improvement in the range of 0.5% to 5% for all the water quality parameters at all stations. On validating the recommended model, it was found that the model satisfactorily predicted all the water quality parameters (R2 values equal or bigger than 0.9). © 201
Oil palm waste based phthaloyl cellulose: a product of photosynthesis as an electrolyte of photovoltaics
No full textAbstract: Waste to wealth extraction of cellulose from oil palm empty fruit bunch was performed. The extracted cellulose was then transformed to an organosoluble derivative, phthaloyl cellulose (PhC). Attachment of the aromatic group was verified by 13 C NMR and FTIR whereas XRD diffractograms endorsed the diminished crystalline nature of the derivative compared to its native form. Ionic conductivity of gels fabricated from PhC incorporated with LiI/I 2 /DMSO recorded a maximum value of 9.73 mS/cm at 13 wt% LiI. As the gel electrolytes were applied in N719 dye based dye-sensitized solar cell, the highest photoconversion efficiency of 3.29% was attained upon addition of 10 wt% LiI. Graphical abstract: [Figure not available: see fulltext.]. © 2019, Springer Nature B.V
Court referral and Nigeria's Financial Regulation Advisory Council of Experts (FRACE)
No full textPurpose: This paper aims to highlight resolution of Islamic finance dispute by common law-oriented courts in Nigeria with respect to Sharīʿah non-compliance and legal risks thereof, as well as the lesson to learn from Malaysia in that regard. This is with view to ensuring Sharīʿah compliance and legal safety of Islamic finance practice as prerequisites for sustainability of the Nigerian Islamic finance industry. Design/methodology/approach: A qualitative method was used; interviews were conducted with different categories of experts and primary data collected in relation to Sharīʿah non-compliance and legal risks in adjudicating Islamic finance dispute by civil courts and the role of expert advice as basis for court referral to Financial Regulation Advisory Council of Experts. A doctrinal approach was adopted to analyse relevant legislative provisions and content analysis of secondary data relevant to applicable provisions in matters of finance before civil courts. Findings: The paper discovers an indispensable role of conventional financial regulations in sustaining Islamic finance industry. Appropriate laws for Islamic finance under the conventional framework foster legal safety and Sharīʿah compliance of Islamic finance activities in related cases handled by courts. Nigeria civil courts can aid sustainability of Islamic finance when so equipped and enabled by laws that address apparent Sharīʿah non-compliance and legal risks in judicial dispute resolution. Inadequate legal provisions for dispute resolution breeds Sharīʿah non-compliance and legal risks in Islamic finance, undermine its prospects and stand inimical to its sustainability. Research limitations/implications: This research is limited by its focus on Sharīʿah non-compliance and legal risks alone, which emanate mainly from judicial resolution of Islamic finance dispute by Nigerian civil courts. Practical implications: This research seeks to motivate a determined and deliberate regulatory action and change in approach towards addressing apparent risks associated with Islamic finance while resolving disputes therein by civil courts. It has implications on common law jurisdictions generally that adopt similar approach as Nigeria's while introducing Islamic finance into their conventional finance framework. Originality/value: Dispute resolution and other regulatory functions of civil courts are important to Islamic finance though apparently overlooked while introducing Islamic finance in Nigeria as in other emerging jurisdictions. This research ascertains the role of the civil courts as indispensable for Islamic Financial Institution (IFIs) operations and demonstrates that such courts are needed for the development and sustainability of Islamic finance industry. The research demonstrates the end-to-end requirement of Sharīʿah compliance of Islamic financial transactions as absolute and needs be ensured and guarded at dispute resolution level by properly equipped courts. © 2019, Zakariya Mustapha, Sherin Kunhibava and Aishath Muneeza
Q-Switched Thulium-Doped Fiber Laser with Pure Titanium-Film-Based Saturable Absorber
No full textWe demonstrate the generation of Q-switching pulse train in thulium-doped fiber laser (TDFL) cavity by employing titanium-based saturable absorber (Ti-SA). The Ti-SA was fabricated by depositing titanium particles molecules using electron beam evaporation on the surface of a polyvinyl alcohol (PVA) film. Subsequently, stable Q-switched pulses were obtained within the 1,552 nm pump power range from 272.1 to 467 mW, with repetition rate tuned from 21.8 to 39.1 kHz. At the maximum pump power, the TDFL showed that the pulse duration of 2.22 μs and the maximum pulse energy of 124 nJ. © 2019, © 2019 Taylor & Francis
Composition and thickness dependence of TLD relative dose sensitivity: A Monte Carlo study
No full textAbsorbed dose sensitivity (SAD) of a dosimeter results from absorbed dose energy dependence (f) and intrinsic energy dependence (kbq) both influenced by compositional and dimensional details. Within attenuating media the SAD is also affected by the depth at which measurements are made as beam quality varies. Monte Carlo simulations allow for studying absorbed dose, importantly providing an effective means by which correction terms for detector response (frel) can be determined. Among the wide range of TLD materials that are available, most generally in particular geometries and size, the commercial products TLD-100 and TLD-100H are perhaps the types most commonly favoured by users. Comprising lithium fluoride (Li natural) co-doped with the activators Mg and Ti or Mg, Cu and P and compressed in a teflon binder to form thicknesses of from 1 mm to a few mm, these have been investigated in previous studies. For some common TLD materials available in small thickness, from 0.125 mm up to 1.000 mm, present study seeks to calculate and compare frel values obtained at different measurement depths in water relative to a reference depth. In simulating a reference radiation field, use has been made of the MCNPX code, calculation providing the correction factors at various depths in a water phantom. Results show that at sub-millimeter dimensions, the effect of detector thickness is more pronounced than the effective atomic number, Zeff, and density of the TLDs. Smaller thickness and higher Zeff TLDs need significant correction factors, with their deviation from unity increasing with the depth up to 15 cm; frel values in the range of 0.96–1.01 were obtained in this study. Perturbation resulting from the presence of the dosimeter was also evaluated in terms of dosimeter size and material composition. Although dosimeter size, density and Zeff are well-known parameters, all important in assessing the amount of perturbation, it has been shown herein that the effect of density is more pronounced than Zeff. For the particular TLDs it is also shown that 0.125 mm thick dosimeters produce a perturbation that might be considered negligible for radiation fields larger than a few centimeters. © 2019 Elsevier Lt
Hirshfeld surface analysis of some new heteroleptic Copper(I) complexes
No full textSeven new coordination complexes namely, [Cu(T1) (I) (PPh3)2] (CT1), [Cu(T2) (I) (PPh3)2] (CT2), [Cu(T3) (I) (PPh3)2] (CT3), [Cu(T4) (I) (PPh3)2] (CT4), [Cu(T5) (I) (PPh3)2] (CT5), [Cu(T6) (I) (PPh3)2] (CT6) and [Cu(T7) (I) (PPh3)2] (CT7), were synthesized and characterized by using spectroscopic and crystallographic methods. The results from spectroscopic data and crystal structure analysis showed that in all complexes, the acylthiourea ligands coordinated as monodentate S-donor mode. All of the complexes displayed distorted tetrahedral geometry with one iodide anion, two triphenylphosphine ligands and one acylthiourea ligand (N-benzoyl-N′-(substituted phenyl)thiourea bearing different ortho/meta-substituents; R–H, 3-Me, 3-OMe, 3-OH, 3-Cl, 2-Me and 2-OMe, T1-T7 respectively) attached to the Cu(I) central metal atom. The acylthiourea ligands behaved as a monodentate S-donor ligand instead of its common O, S-bidentate nature due to the tetrahedrally favored geometry of the copper(I) metal and the presence of two bulky group of triphenylphosphine ligand as the co-ligand. Interestingly, CT1-CT4 and CT7 crystals are isostructural and crystallized in the monoclinic P21/c crystal system whereas CT5 and CT6 are also isostructurally crystallized in the triclinic P1¯ crystal system. Isostructural structures of these two crystal systems illustrated almost similar crystal packing but with significantly different interactions as determined by Hirshfeld surface analysis which is discussed herein. © 201
Perceptions on radioprotective garment usage and underlying reasons for non-adherence among medical radiation workers from public hospitals in a middle-income Asian setting: A qualitative exploration
No full textBackground: Radioprotective garments protect medical radiation workers from exposure to radiation at workplace. However, previous studies have found poor adherence to the use of radioprotective garments. Objectives: We explored the perceptions and practices related to the use of radioprotective garments among medical radiation workers in public hospitals, and sought to understand the reasons for non-adherence. Design and setting: A qualitative approach was applied by conducting face-to-face in-depth interviews with 18 medical radiation workers from three university hospitals using a semi-structured interview guide. Results: Five themes emerged with respect to perceptions on the use of radioprotective garments: (i) the dilemmas in practising radiation protection, (ii) indication of workers' credibility, (iii) physical appearance of radioprotective garments, (iv) practicality of radioprotective garment use, and (v) impact on workflow. Actual lack of radioprotective garment use was attributed to inadequate number of thyroid shield and other garments, radioprotective garments' unsightly appearance including being dirty and defective, impracticality of using radioprotective garments for some nuclear medicine procedures, disruption of workflow because of workers’ limited movements, attitudes of workers, and organisational influences. Conclusion: Medical radiation workers demonstrated a definitive practice of using radioprotective aprons, but often neglected to use thyroid shields and other garments. Availability and hygiene are reported as the core issues, while unclear guidelines on practical use of radioprotective garments appear to lead to confusion among medical radiation workers. To the best of our knowledge, this is the first qualitative study of its kind from a middle-income Asian setting. © 201
Functional characterization of two variants in the 3’-untranslated region (UTR) of transcription factor 4 gene and their association with schizophrenia in sib-pairs from multiplex families
No full textTranscription factor 4 (TCF4) gene plays an important role in nervous system development and it always associated with the risk of schizophrenia. Since miRNAs regulate targetgenes by binding to 3'UTRs of target mRNAs, the functional variants located in 3′UTR of TCF4 are highly suggested to affect the gene expressions in schizophrenia. To test the hypothesis regarding the effects of the variants located in 3'UTR of TCF4, we conducted an in silico analysis to identify the functional variants and their predicted functions. In this study, we sequenced the 3'UTR of TCF4 in 13 multiplex schizophrenia families and 14 control families. We found two functional variants carried by three unrelated patients. We determined that the C allele of rs1272363 and the TC insert of rs373174214 might suppress post- transcriptional expression. Secondly, we cloned the region that flanked these two variants into a dual luciferase reporter system and compared the luciferase activities between the pmirGLO-TCF4 (control), pmirGLO-TCF4-rs373174214 and pmirGLO-TCF4-rs1273263. Both pmirGLO-TCF4-rs373174214 and pmirGLO-TCF4-rs1273263 caused lower reporter gene activities, as compared to the control. However, only the C allele of rs1272363 reduced the luciferase activity significantly (p = 0.0231). Our results suggested that rs1273263 is a potential regulator of TCF4 expression, and might be associated with schizophrenia. © 2019 Elsevier B.V