69 research outputs found
Normal soaking extraction (NSE) of rotenone from Derris elliptica
Derris elliptica or the tuba plant contains rotenone, bio-active compound known that has the potential to be used as bio-pesticide. Bio-pesticide is the best-known alternative bio-pesticide which has the potential to replace the use of conventional pesticides, as it is more environmentally friendly. The main objective of the paper is to obtain the best extraction solvent for optimizing the yield in rotenone extraction. Rotenone was extracted from Derris root using three different parts of roots and three types of solvent in Normal Soaking Extraction (NSE). The types of Derris roots are: (1) Fine root (2) Coarse root (3) Stem. The three types of solvent system are: (1) Acetone 95 % (v/v), (2) Chloroform 99.9 % (v/v) and (3) a mixture of ethanol: H2O (9:1) added with oxalic acid (1mg/ml). The liquid crude extracts were further cleaned up to remove the fine debris of roots. The presence of rotenone was confirmed using qualitative analysis Thin Layer Chromatography (TLC) and thereupon the determination of rotenone content was carried out using High Performance Liquid Chromatography (HPLC). From the results obtained, it was found that the Normal Soaking Extraction (NSE) using acetone 95 % (v/v) was the best method to extract the highest yield of rotenone; 1.14 % (w/w)
Boerhaave\u27s syndrome: a diagnostic dilemma in the emergency room
Boerhaave\u27s syndrome is a potential lethal condition which presents not only a diagnostic but also a therapeutic challenge. Errors in diagnosis are usually caused by unawareness of its varied and atypical presentations. All clinicians need to be aware of this lethal disease, its frequent unusual presentations and the importance of early diagnosis
Exploring the relationship between writing apprehension and writing performance: a qualitative study
Writing skill is seen as a cornerstone of university students’ success in both academic and career life. This
qualitative study was conducted to further explore the teachers’ and students’ perceptions on the relationship
between writing apprehension and writing performance, contributing factors of writing apprehension, and
strategies to reduce writing apprehension. Semi-structured interviews were conducted to get more in-depth
information from two respondents: one experienced instructor of teaching writing at the Centre for Languages
and Pre-University Academic Development (CELPAD), International Islamic University Malaysia, and another,
a graduate student who was reported to having a high level of writing apprehension using Daly and Miller’s
(1975) questionnaire on writing apprehension. Thematic analysis approach was used for data analysis. Both
respondents were convinced that writing apprehension has a negative influence on students’ writing performance;
the sources of contributing factors could be students, instructors, and teaching learning setting; and writing
apprehension could be reduced through suggested strategies. It is recommended that instructors should be more aware of students’ problems in the writing skill
INTER-RELATIONSHIPS AMONG SPEAKING ANXIETY, CONFIDENCE AND PERCEIVED ABILITY IN ENGLISH ORAL COMMUNICATION OF MALAYSIAN SCIENCE AND TECHNOLOGY UNDERGRADUATES
The use of English as a second language (ESL) in oral communication is crucial for science and technology
undergraduates. However, studies have found that Malaysian undergraduates continue to struggle with
low levels of English oral communication due to several factors such as speaking anxiety, low selfconfidence and low perceived ability in oral communication. There is still a need for further research to
investigate the inter-relationships among these factors, and how they affect the English oral
communication level among Malaysian science and technology undergraduates. Hence, this study aimed
to identify the levels of English speaking anxiety, self-confidence and perceived ability in English oral
communication, and find inter-relationships among the three factors. Three hundred (300) final year
science and technology undergraduates were selected from three Malaysian public universities to
complete a survey on factors affecting English oral communication. The Rasch Measurement modeling
for polytomous data, descriptive statistics and Pearson correlation coefficient test were utilized to
analyze the collected data. Overall, science and technology undergraduates showed moderate level of
speaking anxiety, low self-confidence, and yet, high level of perceived ability in English oral
communication. There are significant negative relationships between English speaking anxiety with self confidence and perceived ability in English oral communication. Recommendations are presented based
on the research findings
English language speaking anxiety, self-confidence and perceived ability among science and technology undergraduate students: a rasch analysis
The purpose of this paper is to analyse English language speaking anxiety, self-confidence, and perceived ability in English oral communication among Science and Technology undergraduate students. It also aims to identify any significant differences in these constructs based on selected students’ demographic variables. The study employed the survey method with a 41-item questionnaire administered to a voluntary response sample of three hundred 3rd and 4th-year science and technology undergraduates from three Malaysian public universities. The Polytomous Rasch model was used to analyse the data. The analysis showed that the participants experienced English speaking anxiety, low confidence, and high perceived ability in English oral communication. There were significant mean differences in English speaking anxiety across the type of university as well as in confidence and perceived ability based on academic program. The participants were more confident and could perform better in familiar situations and communicate on familiar topics to familiar audiences. The findings suggest that the participants need more training on English oral communication. More authentic situations are also needed for them to practise and improve their proficiency levels. Other suggestions include providing lecturers with training modules, re-assessing the current language policies, and implementing certain programmes at the tertiary education level. Language programmes could be directed towards more social situations to enable undergraduates to make English a social practice, lower English speaking anxiety, and boost confidence
Factorial validity and invariance of the MUET essay writing rating scale: empirical and theoretical correspondence
Purpose – The validity of any performance assessment depends substantially on the rating scale used in the assessment procedure. It delineates the theoretical construct being measured and influences how performances are judged and interpreted. This study examined the factorial validity and invariance of the rating scale used for the assessment of the essay writing component of the Malaysian University English Test (MUET) in terms of the correspondence to empirical data and the theoretical construct of ESL writing. Methodology – To determine the factorial validity of the MUET essay writing rating scale, a measurement model was developed based on the criteria description of the scale. Model-data ft was
tested using CFA. The data comprised 392 essays, taken from a university English profciency examination. Factorial invariance was tested through consecutively more restrictive models. Results – A 3-factor structure model was found to produce the best ft to the data. Factorial invariance was tested by examining the
comparability of the structure and values of parameters within the model across two groups. A more restrictive model was subsequently tested, where variances and covariances of the latent constructs together with factor loadings were constrained to be equal for the two groups. The resultant goodness-of-ft indices showed a better ft to the data, providing support for the factorial invariance of the 3-factor structure model.
Significance – The results support a 3-factor structure model,congruent with the theory of ESL writing. However, further validation needs to be carried out across different ESL populations to ensure accurate representation and assessment of ESL writing
performance
English language speaking anxiety, self-confidence and perceived ability among Science and Technology undergraduate students: a rasch analysis
The purpose of this paper is to analyse English language speaking anxiety, self-confidence, and perceived ability in English oral communication among Science and Technology
undergraduate students. It also aims to identify any significant differences in these constructs based on selected students’ demographic variables. The study employed the survey method with a 41-item questionnaire administered to a voluntary response sample of three hundred 3rd and 4th-year science and technology undergraduates from three Malaysian public universities. The Polytomous Rasch model was used to analyse the data. The analysis showed that the participants experienced English speaking anxiety, low confidence, and high perceived ability in English oral communication. There were significant mean
differences in English speaking anxiety across the type of university as well as in confidence and perceived ability based on academic program. The participants were more confident and could perform better in familiar situations and communicate on familiar topics to familiar audiences. The findings suggest that the participants need more training on
English oral communication. More authentic situations are also needed for them to practise and improve their proficiency levels. Other suggestions include providing lecturers with training modules, re-assessing the current
language policies, and implementing certain
programmes at the tertiary education level. Language programmes could be directed towards more social situations to enable undergraduates to make English a social
practice, lower English speaking anxiety,
and boost confidence
A phase 1b/2, open-label, dose-escalation, and dose-confirmation study of eribulin mesilate in combination with capecitabine
Background: Capecitabine and eribulin are widely used as single agents in metastatic breast cancer (MBC) and have nonoverlapping toxicities.
Methods: In phase 1b (dose escalation), patients with advanced, treatment-refractory, solid tumours received eribulin mesilate intravenously in 21-day cycles according to schedule 1 (day 1) or schedule 2 (days 1, 8) with twice-daily oral capecitabine (1000 mg/m² days 1–14). In phase 2 (dose confirmation), women with advanced/MBC and ≤3 prior chemotherapies received eribulin mesilate at the maximum tolerated dose (MTD) per the preferred schedule plus capecitabine. Primary objectives were MTD and dose-limiting toxicities (DLTs; phase 1b) and objective response rate (ORR; phase 2). Secondary objectives included progression-free survival (PFS), safety, and pharmacokinetics.
Results: DLTs occurred in 4/19 patients (schedule 1) and 2/15 patients (schedule 2). Eribulin pharmacokinetics were dose proportional, irrespective of schedule or capecitabine coadministration. The MTD of eribulin was 1.6 mg/m² day 1 for schedule 1 and 1.4 mg/m² days 1 and 8 for schedule 2. ORR in phase 2 (eribulin 1.4 mg/m² days 1, 8 plus capecitabine) was 43% and median PFS 7.2 months. The most common treatment-related adverse events were neutropenia, leukopenia, alopecia, nausea, and lethargy.
Conclusions: The combination of capecitabine and eribulin showed promising efficacy with manageable tolerability in patients with MBC
Hidrogel berasaskan pektin kulit buah naga (Hylocereus polyrhizus) sebagai pembawa ubat melalui sistem penghantar oral
Kajian ini memfokuskan kepada aplikasi hidrogel berasaskan ekstrak pektin daripada kulit buah naga (Hylocereus polyrhizus) yang digunakan sebagai biobahan pembawa ubat. Sebanyak 5 sampel telah disediakan dengan peratus komposisi pektin yang berbeza (0%, 0.5%, 1.0%, 1.5%, 2.0%). Keputusan menunjukkan hidrogel dengan 1.0% pektin telah mengembang secara maksimum pada pH 7. Imej daripada mikroskop elektron pengimbas (SEM) mendapati saiz keporosan hidrogel meningkat dengan penambahan pektin. Potensi hidrogel sebagai agen pembawa ubat telah dilakukan dengan melihat kecekapan muatan ubat, ujian perlepasan ubat dan ujian biodegradasi di dalam saluran pencernaan menggunakan medium simulasi perut (SGF), usus (SIF) dan kolon (SCF) secara in-vitro secara tanpa/kehadiran enzim. Hasil ujian ketoksikan menggunakan kaedah embrio ikan kuda belang (Danio rerio) telah memberikan keputusan yang negatif terhadap hidrogel yang diuji
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