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1.
In the present work, the potential of acaricidal activity of chamomile flowers' extract was studied against engorged Rhipicephalus annulatus tick under laboratory condition. For this purpose, the engorged females of Rhipicephalus annulatus were exposed to two-fold serial dilutions of chamomile flowers' extract (0.5%, 1.0%, 2.0%, 4.0% and 8.0%) using "dipping method" in vitro. The engorged ticks were immersed in different plant dilutions (five ticks for each dilution) for 1 min and they were imme-diately incubated in separate Petri dishes for each replicate at 26 °C and 80% relative humidity. Mortality rate for each treatment was recorded 5 d after incubation. The mortality rate caused by different dilutions of chamomile flowers' extract ranged from 6.67% to 26.7%, whereas no mortality was recorded for non-treated control group. The mass of produced eggs varied from 0.23 g (in 8.0% solution) to 0.58 g (in control), with no statistical differences between the treatments and control (P>0.05). Also the chamomile flowers' extract in highest concentration used (8.0%) caused 46.67% failure in egg laying in engorged females while no failure was observed for non-treated control group. Macroscopic observations indicated that in effective concentrations of plant (4.0% and 8.0%), patchy hemorrhagic swelling appeared on the skin of treated ticks. The results presented for the first time in this study imply that chamomile may be considered as a promising plant for biocontrol of cattle fever tick disease in the field condition.  相似文献   

2.
This study examined how much 4-year-old children know about herbs and spices. We researched how much knowledge children could obtain through experiential learning by growing plants in an herb garden and by using herbs and spices in their food. An experiment with one control and one experimental group was carried out, each comprising 18 children. With semi-structured interviews, the authors established the state of the children's previous knowledge on herbs and spices and recognition of plants, exemplified by growing plants and plants used in food dishes. Children from the experimental group then continued to grow herbs and spices and use them in food dishes. Following these activities, the acquired knowledge was established with repeated semi-structured interviews in both groups. At the beginning of the experiment, the children's prior knowledge and recognition of plants were very rudimentary. Only 33% of the children in the experimental group recognized parsley, 22% of them knew chamomile, and 17% of them knew sage and chamomile in tea. Following the activities, children of the experimental group showed statistically significant improvement in plant recognition (mint 100%, oregano on pizza 100%, chamomile 94%, parsley 94%, and oregano 94%). We conclude that through activities of growing plants in herb gardens and their use as food ingredients already in early childhood when eating patterns develop, children obtain much knowledge of herbs and spices.  相似文献   

3.
A brain-computer interface (BCI) -based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control system makes use of the amplitude enhancement of alpha-wave blocking in electroencephalogram (EEG) when eyes close for more than 1 s to constitute a BCI for the switch control of wheelchair movements. The system was formed by BCI control panel, data acquisition, signal processing unit and interface control circuit. Eight volunteers participated in the wheelchair control experiments according to the preset routes. The experimental results show that the mean success control rate of all the subjects was 81.3%, with the highest reaching 93.7%. When one subject's triggering time was 2.8 s, i.e., the flashing time of each cycle light was 2.8 s, the average information transfer rate was 8.10 bit/min, with the highest reaching 12.54 bit/min.  相似文献   

4.
Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects, none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%-100% whereas in S. zeamais, the mortality ranged from 87.5%-100% and 70%-100% in concentrations of 1 g extract+3 ml methanol and 1 g extract+5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract+l 5 ml methanol had no significant lethal effect on Sitophilus zeamais.  相似文献   

5.
The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO2-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO2-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO2 evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (Co) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation.  相似文献   

6.
Objective: To evaluate the efficacy and the indication of basic fibroblast growth factor (bFGF) in the treatment of exposure of orbital implants. Design: Retrospective and observational case series. Methods: We reviewed 41 patients (41 eyes) suffering exposure of orbital implants from Jan. 2000 to June 2006. The study group patients with mild exposure received combined treatment with bFGF and antibiotic drops, and while the control group patients with mild exposure were treated with antibiotic drops only. The study group patients with moderate and severe exposure received combined treatment with bFGF and antibiotic drops, and after 2 months they were subjected to amniotic membrane transplantation, while the control group patients with moderate and severe exposure underwent amniotic membrane transplantation after using antibiotic drops. Observation of the growth of conjunctival epithelium and comparison of the healing rate of the two groups. Results: The healing rates of the mild, moderate and severe exposure study group were 100% and 92.3%. The healing rates of the mild, moderate and severe exposure control group were 55.6% and 66.7% respectively. The difference of the healing rates of the mild exposure study group and the control group was significant (P=-0.033). And the difference of the healing rates of the moderate and severe exposure study group and the control group was not significant (P=-0.167). Conclusion: bFGF may promote obviously the healing of orbital implant exposure, particularly it can be the first choice for the treatment of mild degree exposure. For the moderate and severe cases, it can be administered before surgical repair to enhance neovascularization and will tend to increase the success rate of surgical repair.  相似文献   

7.
Psidium guajava (guava) leaf is a phytotherapic used in folk medicine to treat gastrointestinal and respiratory disturbances and is used as anti-inflammatory medicine. In nuclear medicine, blood constituents (BC) are labelled with technetium-99m (^99mTc) and used to image procedures. However, data have demonstrated that synthetic or natural drugs could modify the labelling of BC with ^99mTC. The aim of this work was to evaluate the effects of aqueous extract of guava leaves on the labelling of BC with ^99mTc. Blood samples of Wistar rats were incubated with different concentrations of guava extract and labelled with ^99mTc after the percentage of incorporated radioactivity (%ATI) in BC was determined. The results suggest that aqueous guava extract could present antioxidant action and/or alters the membrane structures involved in ion transport into cells, thus decreasing the radiolabelling of BC with ^99mTc. The data showed significant (P〈0.05) alteration of ATI in BC from blood incubated with guava extract.  相似文献   

8.
9.
In national perception, education is essentially for all. This is fundamental to all-round development, material and spiritual. It refines sensitivities and perceptions that contribute to national cohesion, a scientific temper and independence of mind and spirit--thus furthering the goals of socialism secularism and democracy enshrined in our constitution. The objective of the study focuses on achievement of children with learning disability in science. There are 5 null hypothesis tested in this research. The sample used in this study includes 35 children with learning disabilities in experimental group and 42 children with learning disabilities in control group. The different views taken on special education have ignited spark of controversies over segregating some children from the mainstream and providing them with extra opportunities. There are arguments for and against both special education and integrated education. Special education means the specifically designed instruction that meets the unusual needs of special children. It requires special materials, teaching, techniques, equipment and facilities. The design was an experimental research pre and post-test equivalent group. The research shows that there is no significant difference in all learning objective such as knowledge, comprehension and skill between control group and experimental group in the pre-test. This two sample groups also did not show any significant difference in the pre-test irrespective of gender, educational qualification of the teacher, years of experience of the teacher, parents' education, parents' profession, parents' income, type of management and type of school. On the other hand, for the post-test all the characteristics show that there are significant differences. This shows that there are effects on the treatment group in learning objective. Furthermore the experimental group showed significantly higher gain score than the control group with regard to the learning objective which comprises of knowledge, comprehension, application and skill.  相似文献   

10.
Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance (TBARS) and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant (wild type). Leaf discs were incubated in 20%, 40% (w/v) polyethylene glycol (PEG) 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/(m^2·s)]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase (SOD), catalases (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and dehydroascorbate reductase (DHAR) were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation (TBARS content) was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress.  相似文献   

11.
12.
A quasi-experiment was conducted at an elementary school to investigate if guided collaboration would facilitate programming learning of 6 graders. Sixty-six students of two intact classes learned to program in KPL (kid's programming language) for 18 weeks during the experiment. One class was randomly assigned to the control group (i.e., free-collaboration) and the other to the experimental group (i.e., guided-collaboration). Students in both groups formed heterogeneous teams of 3 persons. The guided-collaboration teams in experimental group were provided with a worksheet for every programming task. The worksheet contained a set of task-specific guiding questions to guide students through the problem-solving process in a systematic and disciplined manner. An analysis of test scores showed that the experimental group significantly outperformed the control group in the achievement tests, suggesting that the guiding questions were useful in enhancing students' comprehension of programming concepts and developing their programming skills. A comparison of the amount of time spent at each problem-solving step showed that the experimental group spent significantly more time than the control group at the analysis/design/coding step as well as the reflection step. Conversely, the control group spent considerably more time at the debugging step. With the help of the guiding questions, students in the experimental group were also more able to conduct meaningful discussions.  相似文献   

13.
This paper was intended to investigate the effects of using e-books (or texts with multimedia support) in an ERP (extensive reading program) on EFL (English as a foreign language) learners' attitudes toward reading in English. In a junior high school in northern Taiwan, 109 students from 3 intact classes were recruited in the 10-week ERP of e-books. Each class was introduced to a list of 140 selected e-books for the reading program; each student was then encouraged to read e-books after school, with the target of reading 4 e-books every week. The degree of changes in reading attitudes was assessed by using the reading attitudes scale (Stokmans, 1999) before and after the e-book ERP. In addition, the teacher's class notes of the students' reading behaviors and reactions as well as their spontaneous oral or written feedback were analyzed to be triangulated with the quantitative data. The results showed that the e-books had positive effects on the students' attitudinal changes in all dimensions of reading attitudes, namely, utility, development, enjoyment and escape, as well as in all the cognitive, affective and conative components. The results also showed that the features of the e-books, especially oral reading, highlighting, animations and music/sound effects, were considered important to change their attitudes. The implementation of interaction and learner control in the e-books guaranteed positive attitudinal changes as well.  相似文献   

14.
This study aims to measure girls' technical and vocational high school students' information and communication technology (ICT) skills and to investigate these in terms of different variables. The singular and relational survey model was used in this study. The sample composed of 119 technical and vocational high school students. The data were collected through a paper-based survey composed of two parts. In the first part of the survey, there are 15 items about personal information and demographic information about the participating students. In the second part, there is a scale about ICT skills. The data were analyzed by Statistical Package for Social Sciences (SPSS) Version 21.0 by means of percent, frequency, mean, mode, median, Mann-Whitney U, and Kruskall-Wallis test. The results showed that there were no significant differences in the technical and vocational high school students' ICT skills with respect to gender, class level, experience in the use of computers, frequency of using the Internet, working style, learning style, and motivation style. As for the "number of aim using the Internet" variable, a significant difference in the ICT skills scale was observed.  相似文献   

15.
Objective: The prevalence of non-alcoholic fatty liver disease (NAFLD) has markedly increased. Insulin resistance has been implicated in the pathogenesis of NAFLD. This study was aimed at observing the relationship between insulin resistance and NAFLD, and evaluating the role of pioglitazone (PGZ) acting as insulin-sensitizing agents in the prevention and treatment of rat fatty liver induced by high fat feeding. Methods: The rats were separated randomly into 6 groups: model group Ⅰ were fed high fat diet for 8 weeks, PGZ prevention group were given PGZ 4 mg/(kg.d) simultaneously, while control group Ⅰ were fed normal food for 8 weeks; model group Ⅱ were fed high fat diet for 16 weeks, PGZ treatment group were given PGZ 4 mg/(kg.d) orally simultaneous with high fat diet for 8 weeks after high fat feeding for 8 weeks, control group Ⅱ were fed normal food for 16 weeks. The rats were sacrificed after 8 weeks and 16 weeks respectively. Liver weight, body weight, serum activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), tumor necrosis factor alpha (TNF-α), fasting blood glucose (FBG), fasting plasma insulin (FINS), HOMA (homeostasis model assessment) insulin resistance index (HOMA-IR), and the liver histology of rats of all groups were assayed. Results: After 8 weeks, the liver in model group Ⅰ showed typical steatosis, accompanied with mild to moderate lobular inflammatory cell infiltration, liver indexes and serum levels of ALT, AST, ALP, TNF-α were significantly increased (P〈0.05) compared with control group Ⅰ. Whereas, the degree of hepatic injury was attenuated in PGZ prevention group, liver indexes and serum levels of ALT, ALP were significantly decreased (P〈0.05) compared with model group Ⅰ. After 16 weeks, notable steatosis, and lobular inflammation were observed in model group Ⅱ rat liver, while the degree of hepatic injury was attenuated in the PGZ treatment group. Liver index, serum levels ofALT, AST, ALP, FINS and HOMA-IR were significantly increased (P〈0.05) in model group Ⅱ compared with control group Ⅱ. Whereas, in PGZ treatment group, serum levels of AST and FINS showed decreasing tendency, liver indexes, serum levels of ALT, ALP, TNF-α and HOMA-IR were significantly decreased compared with model group Ⅱ. Conclusion: Insulin resistance plays a role in the pathogenesis of NAFLD in rats. Pioglitazone can attenuate insulin resistance and biochemical and histological injury in high fat-induced fatty liver in rats.  相似文献   

16.
Establishing the NCEDL (National Centre for E-learning and Distance Learning), electronic universities are some initiatives to introduce e-learning to the KSA (Kingdom of Saudi Arabia), which have led to a fast, strong, and impressive movement toward e-learning in the Kingdom. However, e-learning in Saudi Arabia is still in the early stage of its development due to many challenges of e-learning that will still have to be faced. E-learning in Saudi higher education has been examined in a number of studies. Yet, focusing on e-learning among Saudi women through the social and religious customs of society is not sufficiently examined. Therefore, this research seeks to investigate the possibilities that exist for the utilization of e-learning in the enhancement of the higher education opportunities of women in Saudi Arabia within the social customs and religious beliefs by identifying the barriers to higher education for Saudi women, the modes of e-learning that currently exist within the higher education programmes in the Saudi higher education system, how e-learning can support higher education opportunities for women in Saudi Arabia, and a successful model of e-learning to improve higher education opportunities for women in the KSA. In order to achieve the aim of this research, a pilot study was made by using a semi-structured interview as a method of data collection from Saudi females who live with their related (mahram) male in the United Kingdom and a three stage coding analysis of the grounded theory analyzing the data collected from the field to formulate a theory and a model. A primarily model was presented which described the contributions of e-learning to higher education of Saudi women. The model is presented consisting of three main categories: (1) social and religious barriers; (2) women's use of the Intemet; and (3) women's use of e-learning, as well as a number of sub-subcategories. In addition, the need to illuminate the ability of Saudi women to convert e-learning into a valuable educational achievement is demonstrated. The next stage of our research will investigate all of the issues indicated by the pilot study in order to improve the success of using e-learning for Saudi women's higher education and eventually to devise a research theory.  相似文献   

17.
The bioactivity of the aqueous extracts of the leaf and stem bark of the medicinal plant, Alstonia boonei De Wild (Apocyanaceae), against the pink stalk borer, Sesamia calamistis Hampson (Lepidoptera: Noctuidae) was studied in a laboratory bioassay. The extracts were incorporated into artificial diet at a rate of 0.0% (control), 1.0%, 2.5%, 5.0%, and 10.0% (w/w). Both extracts significantly (P<0.01) reduced larval survival and weight in a dose dependent manner. The concentrations that killed 50% of the larvae (LC50) for the stem bark extract were 2.8% and 2.1% at 10 and 20 DAI (days after introduction), respectively, while those for the leaves extract were 5.6% and 3.5%. The weights of the larvae also varied significantly (P<0.05) between the treatments in a dose dependent manner. We conclude that both leaf and stem bark extracts of A. boonei are toxic, used as growth inhibitors to S. calamistis larvae, and hold good promise for use as alternative crop protectants against S. calamistis.  相似文献   

18.
Experimental study on behaviors of polypropylene fibrous concrete beams   总被引:1,自引:0,他引:1  
Synthetic fibers made from nylon or polypropylene have gained application when loose and woven into geo textile form although no information on the matrix's mechanical performance is obtained so that more understanding of their structural contribution to resist cracking can be determined. This paper presents the results of an experimental investigation to determine the performance characteristics of concrete reinforced with a polypropylene structural fiber. In this investigation "Fiber mesh" brand of fibers manufactured by SL Concrete System, Tennessee, USA and marketed by M/S Millennium Building System, Inc., Bangalore, India are used. The lengths of the fibers used were 24 mm. Fiber dosages used were 0.9, 1.8, 2.7 kg/m^3. A total of three mixtures, one for each fiber dosage were made. A standard slump cone test was conducted on the fresh concrete mix with and without fibers to determine the workability of the mix. The test program included the evaluation of hardened concrete properties such as compressive, split tensile, modulus of rupture and flexural strengths. The increase in compressive strength is about 36.25%, 26.20%, and 23.75% respectively that of plain concrete. This increase in strength was directly proportional to amount of fibers present in the mix. The increase in flexural strength for Mixes I-III is about 21%, 16.6%, and 23% respectively that of plain concrete specimens. An experimental investigation was also made to study the behaviors of reinforced fibers concrete beams (with longitudinal reinforcements) under two-point loading. The deflection and crack patterns were also studied. The improvements in strength and ductility characteristics were discussed.  相似文献   

19.
The purpose of this study is to examine the attitudes of non-thesis master's degree program: geography teacher candidates towards teaching profession regarding several socio-cultural features. The study was conducted in different universities with 218 geography teacher candidates enrolled in the geography education non-thesis master's degree program. The study was made by survey model. Data were collected by the "Attitude Scales Towards Teaching Profession" developed by ~etin (2006) and "Personal Information Form" developed by the authors. Data were analyzed by t-test, ANOVA (the one-way analysis of variance) (F) and LSD (least significant difference) techniques. The results are given as follows: (1) The average of candidates' attitude grades are in favor of female candidates; (2) There is no difference between whether candidates work at a job; (3) According to variables of the types of high school graduated, educational level of the parents, occupations, income level and living place, there is no difference in candidates' attitudes scores; and (4) Candidates' enrolled in the geography education non-thesis master's degree program reason of preference influence on attitudes to teaching profession.  相似文献   

20.
This paper deals with 2 focal points of inclusive education, which is the integral segment of the current education reform in the Bosnia and Herzegovina: its position in various proclamations and in primary school teachers' reality, i.e., legislative aspects vs. everyday situation in primary schools. The survey research was carried out through the 5-level Liken scale, on the sample of 105 primary school teachers working in Herzegovina-Neretva Canton (specific for its education reform implementation). The aim was to examine the attitudes of the direct implementators of the education reform and the inclusive education (2003-2009)--primary school teachers, with particular reference to: teachers' acquaintance with inclusive education requirements; their involvement in its designing, planning and organization; relevant professional education; school preparedness for inclusive education; level of partnership with relevant subjects; and evaluation of the inclusive education implementation. The results obtained have indicated exactly the lack of the mentioned as the main issues of the implementation of inclusive education within compulsory primary schools in Herzegovina-Neretva Canton. Therefore, this paper gives a kind of guidelines for the improvement of the inclusive education, derived directly from the teachers' everyday experiences, problems, proposals, notes and suggestions.  相似文献   

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