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Effect of drought stress induced by mannitol on secondary products in callus of Golden Sunrise cherry tomatoes were studied in vitro. Seeds were irradiated with gamma at the doses (0, 20, or 40 Gy), and germinated on Murashige and Skoog, (MS) basal medium. Callus were initiated from cotyledon leaf explants using a combination of (2.0 kin + 2.0 IAA mg. l-1) then transferred into MS medium supplemented with mannitol at concentrations of (0, 40, and 60 g.l-1). Vitamin C(vit C), enzyme activity, Ascorbate peroxidase (Apx), and Amylase enzymes, Proline amino acid and β- carotene were quantified by high-performance Performance Liquid Chromatography (HPLC). Results revealed that, highest contents of (Apx) 128.16 µg. ml-1 and 132.6 µg. ml-1 for amylase at 60 g.l-1 of mannitol and 0 Gy of gamma, respectively. Furthermore, the content of VIT C (265.57 µg. ml-1 ) at 20 Gy and 60 g.l-1 of mannitol. The results also showed that a combination of 40 Gy and 60 g.l-1 of mannitol was optimum for the production of high proline amino acids (761.0 µg. ml-1 ) and (113.54 µg. ml-1 ) for β- carotene content in callus culture.

Background: Density is difficult to learn and teach in middle schools. This study, hypothesizing that the density concept develops as part of a conceptual system, used a conceptual change approach to teaching density. The approach emphasized the use of multiple strategies to teach the density concept and the associated concepts in the conceptual system. Purpose: This study assessed post-instructional understanding of different aspects of density in a sample of seventh grade students, examined the effectiveness of the multi-dimensional approach in teaching density, investigated the relations between prior student characteristics and their post-instructional understanding, and investigated if the concept of density develops as part of a conceptual system. Program description: In the first part of the study, student understanding of density was assessed in regular classrooms. In the second part, the investigator and a science teacher co-taught the density unit over a two-week period emphasizing relations between density, mass, volume, part-whole relations, and a scientific particulate conception of matter. A conceptual change approach was used which emphasized multiple representations of knowledge and the use of analogies. Sample: The sample in regular classes consisted of 1,645 seventh graders in 51 schools in the West Bank, Palestine. The intervention group consisted of 29 students in one school. Design and methods: The post-instructional understanding of density in 51 regularly taught classrooms was assessed in the first part of the study using a pencil-and paper test. In the second part, a pre-test was used with the intervention group. Students in both parts of the study took the same post-test. Descriptive statistics were calculated to describe student performance. Comparison between pre-test and post-test performance of students in the intervention group was conducted using "t"-test and ANOVA. Correlations between pre-test sub-scores and post-test scores for students in the intervention class also were calculated. ?[superscript 2] was used to test for co-development of the density concept and other concepts using the different items of the post-test for all groups. Results: Student understanding of density was found poor after instruction, while the intervention had a moderate effect on understanding. Students who started with a basic understanding of some aspects of density gained more from the intervention. The density concept co-developed with the concept of volume and a particulate conception of matter. Conclusions: Teaching density as part of a conceptual system helps promote understanding of the concept. This requires the continuous development and refinement of a learning progression of density, volume, and the particulate nature of matter on the one hand, and an in-depth treatment while teaching the concept on the other hand.

A brief review of the history of pedagogical content knowledge reveals various definitions and conceptualizations of the construct, as well as some conceptual problems. A new conceptualization--teacher pedagogical constructions--is offered to address some of the problems associated with PCK. Seven assertions that comprise the new conceptualization are presented, explained and defended. These are: (1) PCK represents personal and private knowledge; (2) PCK is a collection of basic units called teacher pedagogical constructions; (3) teacher pedagogical constructions result mainly from planning, but also from the interactive and post-active phases of teaching; (4) pedagogical constructions result from an inventive process that is influenced by the interaction of knowledge and beliefs from different categories; (5) pedagogical constructions constitute both a generalized event-based and a story-based kind of memory; (6) pedagogical constructions are topic specific; and (7) pedagogical constructions are (or should ideally be) labeled in multiple interesting ways that connect them to other categories and subcategories of teacher knowledge and beliefs. The proposed definition results from a reconceptualization of the nature of PCK as originally proposed, taking the results of major later studies and conceptualizations of PCK into consideration, appropriating new ideas about the structure of memory, and undertaking a reanalysis and presentation of data from a previous study. The article calls for viewing PCK as neither a subcategory of subject matter (subject matter knowledge for teaching) nor as a general generic form of knowledge. It presents a view of PCK as a collection of teacher professional constructions, as a form of knowledge that preserves the planning and wisdom of practice that the teacher acquires when repeatedly teaching a certain topic. Viewing PCK as a collection of TPCs, more precisely defining it, clarifying its relations to other knowledge and beliefs entities, and speculating about its development should facilitate future investigations of PCK. (Contains 4 figures.)

The present paper describes a project that emphasized the use of case-writing by teachers engaged in an educational innovation. The aims of the paper are threefold: to provide a somewhat detailed description of the case-writing process, to explicate the varied functions of cases and case-writing by teachers, and to discuss an important feature of cases and case-writing that might explain their power. The main argument is that cases could be used to achieve three purposes: to promote, to describe, and to explain teacher and educational change. The description of the case-writing process and an analysis of the cases themselves reveal their great potential in achieving these three aims. Additionally, it is argued that cases and case-writing facilitate border-crossing, or the integration of theory/practice, research/narration, and cognition/emotion, an integration necessary for authentic professional activities. This seminal feature of cases and case-writing also accounts for their potential in achieving the previously mentioned functions.

The study aimed to determine how the oil refinery water affected the growth characteristics of the radish plant. The refinery's water treatment unit's main isolation basins, representing the first factor, pre-treatment water, initiate the cycle, while the final sedimentation basin provides the second factor, post-treatment water. It was used two factors and three replications, with each factor containing seven volumes: 0.00, 0.05, 0.1, 0.15, 0.2, 0.25, and 0.3 Ml/kg. After soil preparation, wastewater was added. It was sowed radish seeds and, after 55 days, doubled the quantity of oil waste water to irrigate the plants. It was harvested the plants during the flowering stage, 129 days after sowing and measured the plant's height, number of leaves, leaf area, total chlorophyll content, root length and diameter, and fresh weight and dry weight. The pre-treatment water had a positive effect on the total chlorophyll content, the length of the roots, and the fresh weight of the root part. These two factors went up by the most, by 12.37%, 26.7%, and 17.05%, respectively. The effect of the pre-treatment water ranged from a decrease to an increase in the average number of leaves, root diameter, fresh weight of the vegetative part, and dry weight of the vegetative and root parts. While its effect was negative for all volumes in the characteristics of plant height and leaf area, it gave the lowest rate of decrease by 20.2% and 26.63% compared to untreated plants. The post-treatment water had a positive impact on the plant height, number of leaves, total chlorophyll content, and fresh weight of the root part. However, it recorded the highest average increases of 61.26%, 36.12%, 6.71%, and 141.71%. While its effect varied according to the amount of water in terms of leaf area, root length, root diameter, and dry weight of the root part, it gave a negative effect in all treatments in terms of the fresh and dry weight of the vegetative part.

Proposes that teachers who undergo accommodative change do so if they are internally motivated to learn; become aware of their implicit ideas and practices and critically examine them; construct alternative knowledge, beliefs, and practices; resolve conflicts between the prior and the new set of ideas and practices; and do so in a social climate characterized by collaboration, trust, reflection, and deliberation. A teacher- written case demonstrates these assertions. (SM)

Describes Palestinian teachers' and students' emotional and cognitive conflicts when introduced to a problem- and case-based approach to democracy education. Observation and case study data indicated that participants sometimes held initial beliefs about democracy, student-teacher interactions, and appropriate classroom behaviors reflecting an authoritarian culture. However, many underwent important changes in their ideas and behavior to reflect democratic relations. (SM)

The main objective of this study is to evaluate the effects of waste water from the Dora refinery's treatment unit on tomato Lycopersicon esculentum grown in three types of soil taken from the same area, with consideration to the number of leaves, lycopene, and beta-carotene content in tomato yield, as well as the plant's ability to absorb the toxic compounds furfural and -1, 2 dibromoethane. The experiment was carried out using pots in the glass house belonging to the Department of Biology, College of Education for Pure Sciences/Ibn Al-Haytham, University of Baghdad, for the seasons 20/9/2022–19/3/2023. The experiment included 45 treatments with 3 types of soil (clay, mixed, and sandy), and each type of soil had 5 treatments with 3 replicates. Control plants were left without treatment for each type of soil. The soil was sprayed with different volumes of water discarded from the treatment unit (0.1, 0.2, 0.3, and 0.4 ml/kg) before planting, and adding the same treatments with irrigation water was repeated after 53 days of planting at the stage of 4-6 leaves. The results showed that the treatment exceeded 0.1 ml. kg-1 soil in leaf area, number of leaves, lycopene, and beta-carotene content, as it gave the highest mean with an increase of 16.48%, 7.52%, 1.21%, and 0.54%, respectively, compared to untreated plants. As for the ability of the fruits to store furfural and 1,2-dibromoethane, it reached the highest average with a volume of 0.4 ml. kg-1 soil. The results also indicated that the mixed soil was superior in all traits except for the fruit content of furfural, which was superior to the clay soil.

Shurshirin Valley and surrounding areas are the most wonderful places as tourist areas in the east of Iraq. Many rock slopes appear as dangerous geological locations along this valley. One of the most effective geological structures on the rock slope stability is the orientation of the joints concerning the attitude of the bedding plane and the slope (inclination angle and direction), thus a geometrical analysis for joints has been performed for rock slopes along Shurshirin Valley to assess their instability; Five stations have been studied for both Tertiary rocks and Alluvial fan sediments which exist in three stations only. The main failure types in the study area are rock fall in all stations, toppling in two stations, and (potentially wedge sliding )in one station along the intersection line of the joint sets concerning the lateral slope of station No.2. While the suggested ways to improve the slope stability and protection versus rock failures are re-slope, trimming, ditches, and wire mesh.