480 research outputs found
Two new species of plant parasitic nematodes Hirschmanniella bananae n.sp. (Nematoda: Pratylenchidae) and Scutellonema tanlamense n.sp. (Nematoda: Hoplolaimidae) associated with banana in Vienam
During investigation on the plant parasitic nematodes on bananas in North and Central provinces of Vietnam carried out in 1995 two new species were found, Hirschmanniella bananae n.sp. and Scutellonema tanlamese n.sp. Hirschmanniella bananae n.sp. is characterized by having 6 annuli in lip region, areolation of entire lateral field and presence of a mid-terminal mucro at the tail end. The new species is close to H. shamini Ahmad, 1972 but differs from H. shamini by longer body length in females (1450-1750 µm vs 1190-1360 mm), longer stylet longer (18-20.5 mm vs 16-19 mm) and longer spicule longer (28-29.5 mm vs 22-25 mm). Scutellonema tanlamese n.sp. is characterized by lip region with three annuli and numerous longitudinal ridges (18) in basal annulus and structure of lateral field at the tail region with inner lines extending to tail terminus. The new species is closest to S. brachyurus type B (African populations) described by Van Den Berg et al. in 2013 but can be distinguished by body length shorter (643-708 µm vs 777-820 µm), stylet length shorter ((24.5-26.5 µm vs 28-29.5 mm, and also by structure of lateral field with two inner lines going throught at tail region and vulval edge distinct with epiptygma appearing double and folded into vagina. Citation: Nguyen Ngoc Chau, 2017. Two new species of plant parasitic nematodes Hirschmanniella bananae n.sp. (Nematoda: Pratylenchidae) and Scutellonema tanlamense n.sp. (Nematoda: Hoplolaimidae) associated with banana in Vienam. Tap chi Sinh hoc, 39(3): 253-263. DOI: 10.15625/0866-7160/v39n3.10665. *Corresponding author: [email protected] Received 19 August 2017, accepted 12 September 201
Pursuing environmental sustainability in the fast fashion industry: A qualitative exploratory research
Objectives: The main objectives of this study were to explore processes associated with producing fast fashion apparels that negatively impact the environment, to explore the sustainability initiatives that big clothing manufacturers and retailers in the fast fashion industry have adopted, and to explore the reporting practice of fast fashion firms concerning their environmental performance.
Summary: For this study, a qualitative content analysis was conducted to analyze a sample of five corporate reports or sustainability reports of fast fashion companies for the fiscal year of 2016. The findings related to the environmental impact of fast fashion industry were addressed by the literature review, while findings on environmental initiatives and reporting practices on environmental performance of fast fashion companies were based on the content analysis of the reports.
Conclusions: The environmental impact of the fast fashion industry stems from transportation, cultivation of raw materials, processing of fibers, and textile waste. Environmental initiatives taken by fast fashion companies can be categorized into product design, process design, supply chain, and customer engagement and awareness. Reporting practices of fast fashion firms on their performance are found to be focused on certain indicators; putting the environmental indicators within the context of the sustainability measures taken, it can be concluded that the measures bring about positive environmental performance outcomes for companies
TEACHERS’ PERCEPTIONS OF SCAFFOLDING EFL STUDENTS’ READING COMPREHENSION AT HIGH SCHOOLS IN THE MEKONG DELTA, VIETNAM
Scaffolding has held great appeal for teachers of English as a foreign language (EFL) and scholars in helping students take greater responsibility or ownership in their language learning and reach academic success. However, little is known about how teachers perceived this type of support as improving students’ reading comprehension in English within the teaching and learning context in Vietnam high schools. This paper therefore reports a descriptive study that explored teachers’ perceptions of scaffolding EFL students’ reading comprehension at high schools in the Mekong Delta, Vietnam. Questionnaires and semi-structured interviews were employed to collect data from seventy-nine high school teachers. The findings provide insightful views into teachers’ perceptions about scaffolding students’ reading comprehension. The findings also reveal how teachers experienced varying degrees of their perceptions of scaffolding and challenges while delivering their scaffolding practices in reading instruction.
Article visualizations
New records of ring nematodes, Bakernema enormese n. sp. and Criconema (Nothocriconemella) graminicola Loof, Wouts & Yeates, 1997 (Nematoda: Criconematidae) from natural forests of Vietnam
Bakernema enormese sp. n., collected from rhizosphere of forest wood trees in Muong Phang, Dien Bien Province (north Vietnam) is described and illustrated. The new species is characterized by large body size and stylet. In general, this new species is close to two existing species of the same genus, B. inaequale and B. dauniense by cuticle structure in transparent membranous projections which appear in lateral view as spine-like structures on each annulus. These structure arranged into several rows along the body. In morphology, the new species differs from B. inaequale and B. dauniense by body and stylet length, i.e. 609–842 µm and 143.5–150 µm vs. 391–578 µm and 59–74 µm for B. inaequale and vs. 391–461 µm and 65–74 µm for B. dauniense. In addition, new species can be distinguished from B. inaequale by the longer membranous projection, 8–12 vs. 6–10 µm and vagina shape, curved vs. sigmoid. From B. dauniense, the new species differs by the much longer membranous projection, 8–12 vs. 1.4–2.2 µm and less number annules between vulva and tail end (RV), 3–4 vs. 7.8 annules. The presence of Criconema (Nothocriconemella) graminicola Loof, Wouts Yeates, in Vietnam with morphometrics, illustrators and remarks given
BLENDED LEARNING IN BADMINTON TRAINING FOR PROFESSIONALS: STUDENTS’ PERCEPTIONS AND PERFORMANCE IMPACTS
As with other subject areas, badminton instruction for practitioners is experiencing a lot of changes under the impact of technology. Recently there has been the possibility of moving badminton training classes to the online platform but there is no consensus on its efficacy. This study is conducted to study the effects of blended learning activities on the perceptions and performance of students in physical education. Forty students in physical education are selected and divided into two groups: an experimental group, and a control group. All groups in face-to-face learning sessions have the same curriculum, course-book, equipment and teaching method. The questionnaire and interview data show that students in blended class sessions had positive perceptions of learning activities. Article visualizations
Nematode morphometry and biomass patterns in relation to community characteristics and environmental variables in the Mekong Delta, Vietnam
Nematode morphometry and biomass were investigated in the dry season of 2009 at the mouth of eight Mekong estuaries in Vietnam. We investigated how morphometry and biomass of nematodes were related to community characteristics and environmental gradients. Mean nematode lengths were significantly greater along the Co Chien estuary. In contrast, there were no significant differences in nematode width, length/width ratio, individual biomass and total biomass between stations at the estuarine mouth and along the Co Chien estuary. This study further confirmed that nematode morphometry and biomass distribution reflect specific modes of life in terms of feeding strategies, life history, and diversity. There were also particular morphotypes associated with specific environmental conditions. Over the whole area and especially along the mouth stations, nematodes were especially longer in sandy substrates where chlorophyll a concentrations were low, possibly due to the presence of predators and an associated reduction in the density of small opportunistic deposit feeders. An increase in the silt fraction together with pigment concentrations, especially along the Co Chien estuary, was positively correlated with the number, total biomass and abundances of small opportunistic genera resulting in a low maturity index and a high number of nematode genera
Numerical modeling of thermal dust polarization from aligned grains in the envelope of evolved stars with updated POLARIS
Magnetic fields are thought to influence the formation and evolution of
evolved star envelopes. Thermal dust polarization from magnetically aligned
grains is potentially a powerful tool for probing magnetic fields and dust
properties in these circumstellar environments. In this paper, we present
numerical modeling of thermal dust polarization from the envelope of IK Tau
using the magnetically enhanced radiative torque (MRAT) alignment theory
implemented in our updated POLARIS code. Due to the strong stellar radiation
field, the minimum size required for RAT alignment of silicate grains is . Additionally, ordinary paramagnetic grains can achieve
perfect alignment by MRAT in the inner regions of due to
stronger magnetic fields of mG - 1G, producing thermal dust
polarization degree of . The polarization degree can be enhanced
to for grains with embedded iron inclusions. We also find that
the magnetic field geometry affects the alignment size and the resulting
polarization degree due to the projection effect in the plane-of-sky. We also
study the spectrum of polarized thermal dust emission and find the increased
polarization degree toward due to the alignment of
small grains by MRAT. Furthermore, we investigate the impact of rotational
disruption by RATs (RAT-D) and find the RAT-D effect cause a decrease in the
dust polarization fraction. Finally, we compare our numerical results with
available polarization data observed by SOFIA/HAWC+ for constraining dust
properties, suggesting grains are unlikely to have embedded iron clusters and
might have slightly elongated shapes. Our modeling results suggest further
observational studies at far-infrared/sub-millimeter wavelengths to understand
the properties of magnetic fields and dust in AGB envelopes.Comment: 27 pages, 23 figures, 1 table, to be submitte
HIỆU LỰC GÂY CHẾT VÀ KHẢ NĂNG SINH SẢN CỦA BỐN CHỦNG TUYẾN TRÙNG KÝ SINH GÂY BỆNH CÔN TRÙNG TRÊN SÂU QUY (Zophobas morio)
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