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Learning to evaluate through that-clauses: Evidence from a longitudinal learner corpus
No full textThe language of evaluation in academic writing has been increasingly studied. However, little is known about how students learn to make evaluative meanings. This article reports on a study of evaluative that-clauses based on a longitudinal corpus of 632 argumentative essays by 158 Chinese undergraduate students. The findings of the study show a non-linear trajectory of change in the use of evaluative that-clauses over time. It was found that the proportion of verb that-clauses decreased whereas the proportions of noun that-clauses and adjective that-clauses increased. Further, while the range of the lexical words co-occurring with evaluative that-clauses expanded, the authorial visibility in stance expression decreased. These changes indicate signs of agency and suggest that the development of evaluative language resources is an organic, dynamic process. Overall the study points to the value of developing and exploring longitudinal learner corpora for studying language learning in general and development in evaluative language in particular. Taking an approach to treating learner language in its own right, the study further contributes to a small but growing body of research based on an empowering ideology and to the empirical literature on evaluation and language learning. Implications for writing instruction are considered
Optical and thermal characterization of silver nanoparticles dispersion in lamellar liquid crystal matrix
No full textThe lamellar lyotropic liquid crystal (LLLC) was used as a host to assemble silver nanopar- ticles (AgNPs) through in situ technique. At first, a mixture of HDTABr/1-pentanol/water was prepared to observe the liquid crystal texture via polarizer microscope. The lamellar texture with intensely arrangement at lower water content was observed, that was also similar texture by replacing Ag solution at lower volume. The UV–vis showed surface plasmon resonance bands were influenced by the concentration of AgNO3. Transmission electron microscopy (TEM) showed nanoparticles were nearly monodispers with an average particles size 4–5 nm at lower Ag+ meanwhile produced even larger with separate aggregate, ∼11 nm average particles size at the highest concentration Ag solution. The emission peaks were enhanced as the AgNO3 concentrations increased. Thermal studies showed evidently most stable at 710 °C for highly concentrated nanoparticles
Anti-ulcerogenic activity of dentatin from clausena excavata Burm.f. against ethanol-induced gastric ulcer in rats: Possible role of mucus and anti-oxidant effect
No full textBackground: Clausena excavata Burm.f. (Rutaceae) has been used for the treatment of stomach disorders including peptic ulcer. Purpose: In this study, we aimed to investigate dentatin isolated from C. excavata Burm.f., for anti-ulcer activity against ethanol ulcer model in rats. Methods: Gastric acid output, ulcer index, serum profile, histological evaluation using Hematoxylin and eosin (HE), periodic acid Schiff base stainings and immunohistochemical localization for heat shock proteins 70 (HSP70) were all investigated. Possible involvement of reduced glutathione (GSH), lipid peroxidation, prostaglandin E2 (PGE2), superoxide dismutase (SOD) enzymes, radical scavenging, and anti-Helicobacter pylori activity were investigated. Results: Dentatin showed anti-secretory activity against the pylorus ligature model and protected the gastric mucosa from ethanol ulceration, as revealed by the improved macroscopic and histological appearance. Dentatin significantly increased the gastric homogenate content of PGE2 GSH and SOD. Dentatin inhibited the lipid peroxidation as revealed by the reduced gastric content of malondialdehyde (MDA). Moreover, dentatin up-regulated HSP70 expression. However, dentatin showed insignificant anti-H. pylori activity. Conclusion: Dentatin possesses gastro-protective activity, which could be attributed to the anti-secretory, mucus production, anti-oxidant, and HSP70 activities
Addressing procedural challenges of ethical review system: Towards a better ethical quality of clinical trials review in Malaysia
No full textThe review of clinical trials with human participants in Malaysia is governed by a decentralized control system. The clinical trial protocols are reviewed by 13 registered research ethics committees (RECs) in Malaysia. A governmental body, the National Pharmaceutical Control Bureau, is responsible for the inspection and oversight of these registered RECs to ensure that they comply with the regulatory requirements. However, this study highlights that each REC in Malaysia has a different standard operating procedure and ethical review process. Other procedural challenges identified include inadequate membership, poor mechanism for research monitoring after ethical approval, and insufficient resources. Establishments of a national standard of REC and a central ethics committee are suggested to ensure procedural compliance in the oversight of clinical trials in Malaysia. While there is a growing concern that procedural compliance may not have a direct impact on the protection of human subjects, our key point is that an ethical review system compliant with the national standards could serve as a strong framework to support and enhance the ethical quality of decision-making and judgement. We believe that being aware of how influential procedural compliance can be would help committees improve the ethical quality of their research review
Phase transition in BaThO3 from Pbnm to Ibmm turn the fundamental energy band gap from indirect to direct
No full textThe influence of phase transition on the electronic structure and the optical properties of BaThO3 is investigated by means of density functional theory. At room temperature BaThO3 is stable in the Pbnm phase, whereas it is stable in the Ibmm phase at high temperature. The transition from the Pbnm to the Ibmm phase cause a change in the band gap (Eg) nature from indirect to direct and a reduction by around 0.3 eV. The calculated Eg is about 4.9 eV (Pbnm) and 4.6 eV (Ibmm). The phase transition influences the k-dispersion of bands around the Fermi level and, hence, the effective masses resulting in increasing the mobility of the charge carrier and enhancing the charge transfer mechanism. The obtained optical properties clearly show the influence of phase transition on the electronic structure. It was noticed that moving from Pbnm →Ibmm phase leads to shift the whole spectral structure towards lower energies by around 0.3 eV and increase the magnitudes of the optical components. It is found that the Pbnm and Ibmm phases exhibit negative uniaxial anisotropy and negative birefringence
Evaluating the effectiveness of information retrieval systems using effort-based relevance judgment
No full textPurpose: The effort in addition to relevance is a major factor for satisfaction and utility of the document to the actual user. The purpose of this paper is to propose a method in generating relevance judgments that incorporate effort without human judges’ involvement. Then the study determines the variation in system rankings due to low effort relevance judgment in evaluating retrieval systems at different depth of evaluation. Design/methodology/approach: Effort-based relevance judgments are generated using a proposed boxplot approach for simple document features, HTML features and readability features. The boxplot approach is a simple yet repeatable approach in classifying documents’ effort while ensuring outlier scores do not skew the grading of the entire set of documents. Findings: The retrieval systems evaluation using low effort relevance judgments has a stronger influence on shallow depth of evaluation compared to deeper depth. It is proved that difference in the system rankings is due to low effort documents and not the number of relevant documents. Originality/value: Hence, it is crucial to evaluate retrieval systems at shallow depth using low effort relevance judgments
Recent developments in metamodel based robust black-box simulation optimization: An overview
No full textIn the real world of engineering problems, in order to reduce optimization costs in physical processes, running simulation experiments in the format of computer codes have been conducted. It is desired to improve the validity of simulation-optimization results by attending the source of variability in the model’s output(s). Uncertainty can increase complexity and computational costs in Designing and Analyzing of Computer Experiments (DACE). In this state-of the art review paper, a systematic qualitative and quantitative review is implemented among Metamodel Based Robust Simulation Optimization (MBRSO) for black-box and expensive simulation models under uncertainty. This context is focused on the management of uncertainty, particularly based on the Taguchi worldview on robust design and robust optimization methods in the class of dual response methodology when simulation optimization can be handled by surrogates. At the end, while both trends and gaps in the research field are highlighted, some suggestions for future research are directed
Molecular characterization of Trichuris species isolated from humans, dogs and cats in a rural community in Peninsular Malaysia
No full textTrichuris trichiura (whipworm) are soil-transmitted helminths (STHs) that causing trichuriasis in human. Trichuris vulpis, a canine whipworm has also been reported occasionally in humans. However, an overlapping dimension in the morphology and due to limited external characters between both species may lead to the potential for misidentification. Although there has been an extensive study on the distribution of whipworm in both human and animal hosts, little is known about the molecular epidemiology of Trichuris species in both hosts. To investigate to characterize the whipworm species and to determine the genetic relationship between species infecting both humans and animals, we sequenced the small subunit ribosomal RNA (SSU rRNA) regions of Trichuris egg isolated from humans, dogs and cats in a rural community in Malaysia. A total of 524 fresh fecal samples were collected from humans and animals. The overall prevalence of Trichuris was 59.9% as determined by microscopy examination. The molecular analysis showed that 98.7% were identified as T. trichiura in the human fecal sample. Interestingly, 1.3% were identified as T. vulpis. As for animal fecal sample, 56.8% and 43.2% were identified as T. trichiura and T. vulpis, respectively. Phylogenetic and sequence analysis demonstrated that T. trichiura isolates were genetically distinct from T. vulpis isolates from both hosts. This finding implies that companion animals can be a reservoir and mechanical transmitter for T. trichiura infection in human and also highlighting the possible zoonotic potential of T. vulpis. This finding may also suggest that cross-transmission between humans and animal hosts in sympatric setting may be a source of infection in both hosts. More studies are needed to better understand the transmission dynamic and public health significance of Trichuris infection in both hosts
LCSS-Based Algorithm for Computing Multivariate Data Set Similarity: A Case Study of Real-Time WSN Data
No full textMultivariate data sets are common in various application areas, such as wireless sensor networks (WSNs) and DNA analysis. A robust mechanism is required to compute their similarity indexes regardless of the environment and problem domain. This study describes the usefulness of a non-metric-based approach (i.e., longest common subsequence) in computing similarity indexes. Several non-metric-based algorithms are available in the literature, the most robust and reliable one is the dynamic programming-based technique. However, dynamic programming-based techniques are considered inefficient, particularly in the context of multivariate data sets. Furthermore, the classical approaches are not powerful enough in scenarios with multivariate data sets, sensor data or when the similarity indexes are extremely high or low. To address this issue, we propose an efficient algorithm to measure the similarity indexes of multivariate data sets using a non-metric-based methodology. The proposed algorithm performs exceptionally well on numerous multivariate data sets compared with the classical dynamic programming-based algorithms. The performance of the algorithms is evaluated on the basis of several benchmark data sets and a dynamic multivariate data set, which is obtained from a WSN deployed in the Ghulam Ishaq Khan (GIK) Institute of Engineering Sciences and Technology. Our evaluation suggests that the proposed algorithm can be approximately 39.9% more efficient than its counterparts for various data sets in terms of computational time
Electrical Behavior of a Nanoporous Nb2O5/Pt Schottky Contact at Elevated Temperatures
No full textThis paper discusses the effects of temperature on Schottky behavior of anodized niobium pentoxide (Nb2O5) used to form a nanoporous structure film. The application of a typical Schottky diode is limited at high temperature, and studies of different materials used in the fabrication are still in demand. Nb2O5 as a Schottky diode operation at elevated temperature has yet to be investigated. A nanoporous structure has the potential of producing high conductivity and also has the ability to spread heat since it has higher surface area. The structure was synthesized by anodizing niobium foils in ethylene glycol-based solution with 0.4 wt.% of H2O in different anodization times; 4 min, 8 min, 10 min, 40 min and 60 min. The anodized films were then annealed for 30 min at 440°C. The metal contact used for current–voltage (I–V) testing was platinum (Pt) and it was deposited via thermal evaporator at 30-nm thickness. Various characterization tests were conducted. Field emission scanning electron microscopy (FESEM) images suggested that longer anodization time produced larger pore sizes. The x-ray diffraction (XRD) confirmed the crystallization of Nb2O5 to be in an orthorhombic phase, while atomic force microscopy (AFM) showed surface roughness decreasing with longer anodization time. Higher surface roughness produced lower leakage current. I–V tests were conducted under different temperatures of 25°C, 50°C, 75°C, 100°C and 125°C to study the heat effect on I–V Schottky behavior of anodized nanoporous Nb2O5. By testing the I–V characteristics at elevated temperature, the electrical parameters were observed to have strong dependency on temperature. A device with lower thickness and operating at higher temperature produced higher current contribution. From I–V tests, it was observed that the increment of barrier height and decrement of ideality factor will be affected by increased temperature. For Schottky Pt/Nb2O5, barrier height increased in the range from 0.91 to 1.05, while the ideality factor decreased from 2.24 to 1.42