Gender,text, and discussion: Examining intellectual safety in the science classroom

It is clear from the extant literature that gender inequities exist in a myriad of ways in science classrooms. Past research, however, has been conducted solely from researchers' observations and has neglected to investigate students' awareness of and reactions to their own experiences. Hence, this study focused on students' perceptions of gender differences in instructional activity and talk about that activity in physics and honors physics classes. Data analysis showed that although teachers may be unaware of gender inequities, students of both sexes are not unaware of such inequities. Females explained their fears of offering their opinions and participating in activities like labs and small-group or whole-class discussions. Differential language patterns were found for males and females, particularly when discussion was structured and rewarded for refutation. Explanations are offered for these disparities and suggestions are given for addressing gender bias in science classrooms. It has been well documented that science classrooms are not gender fair (Bazler & Simonis, 1991; Bianchini, 1993; Tobin, 1988). Teachers, texts, and the forms of instruction they perpetuate contribute to gender inequities in science instruction. For example, research tracing changes in science textbooks over time has shown that current texts have failed to eliminate barriers to women in science (Bianchini, 1993). Science textbooks are criticized for their unequal treatment of genders, with illustrations, photos, and texts of males far outnumbering those of females, despite the approximate 50/50 male/female ratio of our population (Bazler & Simonis, 1991). In addition to the proclivity of science textbooks to favor males, researchers speculate that the tendency for boys to achieve higher than girls in science may be a result of more opportunity to engage in academic tasks (Tobin & Garnett, 1987). Their behavior shows that teachers have differential expectations for students' responses in activities like teacher-led discussion. In teacher-led, whole-class discussion, boys are spoken to more frequently and are asked more higher-order questions (Becker, 1991; Hall & Sadler, 1982). Teachers in science classrooms elaborate more on males' responses than females' responses in large-group discussion of scientific concepts (Jones & Wheatley, 1990). © 1996 John Wiley & Sons, Inc.     

Mineralogy of the deep lower mantle in the presence of H2O

Understanding the mineralogy of the Earth''s interior is a prerequisite for unravelling the evolution and dynamics of our planet. Here, we conducted high pressure-temperature experiments mimicking the conditions of the deep lower mantle (DLM, 1800–2890 km in depth) and observed surprising mineralogical transformations in the presence of water. Ferropericlase, (Mg, Fe)O, which is the most abundant oxide mineral in Earth, reacts with H₂O to form a previously unknown (Mg, Fe)O₂H_x (x ≤ 1) phase. The (Mg, Fe)O₂H_x has a pyrite structure and it coexists with the dominant silicate phases, bridgmanite and post-perovskite. Depending on Mg content and geotherm temperatures, the transformation may occur at 1800 km for (Mg_0.6Fe_0.4)O or beyond 2300 km for (Mg_0.7Fe_0.3)O. The (Mg, Fe)O₂H_x is an oxygen excess phase that stores an excessive amount of oxygen beyond the charge balance of maximum cation valences (Mg²⁺, Fe³⁺ and H⁺). This important phase has a number of far-reaching implications including extreme redox inhomogeneity, deep-oxygen reservoirs in the DLM and an internal source for modulating oxygen in the atmosphere.     

Coronavirus disease(COVID-19):The need to maintain regular physical activity while taking precautions

The on-going Coronavirus disease(COVID-19)outbreak in China has become the world's leading health headline and is causing major panic and public concerns.On January 30,2020,the World Health Organization(WHO)declared that the new coronavirus outbreak is a public health emergency of international concern.1 The virus has already had a direct impact on more than 10 million people in the city of Wuhan and has reached other parts of China as well,posing a health threat of unknown magnitude globally.As of February 8,2020,WHO reported 34,886 confirmed cases of COVID-19 globally,with 34,589 of them occurring in China(including 6101 severe cases and 723 deaths).A total of 288 other confirmed cases(with 1 death)have been reported in 24 countries,including Japan,Australia,Germany,and United States.2 However,these daily estimates are expected to rise even higher as reports from health authorities in China3 are gathered and near real-time updates of the Johns Hopkins virus dashboard are made 4 The outbreak has caused governments in various countries to take swift and protective measures.In China,these included putting cities on lockdown,5 implementing travel wamings/bans and cancellations,6 extending national holidays,and closing schools and postponing classes7.     

DNA microarray wet lab simulation brings genomics into the high school curriculum

We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula.     

Desalination of masonry structures: Fine tuning of pore size distribution of poultices to substrate properties

Desalination is a relatively new intervention in the field of conservation of architectural heritage. Especially the desalination of immovable objects, such as masonry structures, is still a trial-error practice. In the field, different desalination materials and methods are used, sometimes with unsatisfactory results. Better understanding of the desalination process is needed in order to support the conservator with clear guidelines for choosing a suitable desalination material and method. The research presented in this paper constitutes the first step towards the development of a modular system of poultices, which can be adapted, i.e. fine-tuned to different types of substrates. Starting point is to make use of advection, i.e. the transport of salt ions with water flow. This transport mechanism is faster than diffusion and the application on immovable objects is relatively easy. In order to optimize salt extraction, a poultice working by advection should have smaller pores than the substrate. Starting from this principle the pore sizes of different desalination materials (sand, cellulose, kaolin and bentonite) mixed in different proportions, have been measured. Interesting results were obtained, showing that the desalination materials commonly used in the field are often not the most suitable ones. On the basis of the results, recipes for poultices, adapted to a specific substrate, can be formulated.     

Psychometric Properties of a Parental Questionnaire for Assessing Correlates of Toddlers’ Physical Activity and Sedentary Behavior

This study examined the psychometric properties of a questionnaire developed with the guidance of the socialization model of child behaviour to understand modifiable correlates of toddlers’ physical activity and sedentary behaviour. Findings are based on 118 parents (33.7 ± 4.9 years; 86% female) of toddlers (19.3 ± 2.7 months; 48% female) from Edmonton, Canada in The Parents’ Role in Establishing healthy Physical activity and Sedentary behaviour habits study (PREPS). The PREPS questionnaire encompassed 21 variables across the constructs of the socialization model of child behaviour. Of the nine variables assessed for internal consistency reliability, eight had good (α ≥ 0.70) reliability. Of the 15 continuous variables assessed for 1-week test–retest reliability, 10 had moderate (intra-class correlation = 0.50–0.74) and 5 had good (intra-class correlation ≥ 0.75) reliability. Of the six categorical variables assessed for 1-week test–retest reliability, two had fair (К = 0.21–0.40), one had moderate (К = 0.41–0.60), one had substantial (К = 0.61–0.80), and two had almost perfect (К = 0.81–1.00) reliability. Of the 12 sedentary behaviour variables assessed for convergent validity, 7 were significantly correlated with children’s screen time, of which three were small (r ≤ 0.29), two were medium (r = 0.30–0.49), and two were large (r ≥ 0.50) effect sizes.     

Relationship between foot strike pattern,running speed,and footwear condition in recreational distance runners

Compared to competitive runners, recreational runners appear to be more prone to injuries, which have been associated with foot strike patterns. Surprisingly, only few studies had examined the foot strike patterns outside laboratories. Therefore, this study compared the foot strike patterns in recreational runners at outdoor tracks with previously reported data. We also investigated the relationship between foot strike pattern, speed, and footwear in this cohort. Among 434 recreational runners analysed, 89.6% of them landed with rearfoot strike (RFS). Only 6.9 and 3.5% landed with midfoot and forefoot, respectively. A significant shift towards non-RFS was observed in our cohort, when compared with previously reported data. When speed increased by 1 m/s, the odds of having forefoot strike and midfoot strike relative to RFS increased by 2.3 times and 2.6 times, respectively. Runners were 9.2 times more likely to run with a forefoot strike in minimalists compared to regular running shoes, although 70% of runners in minimalists continued to use a RFS. These findings suggest that foot strike pattern may differ across running conditions and runners should consider these factors in order to mitigate potential injury.     

“She My Friend”: Implications of Friend Ideologies,Identities, and Relationships for Bilingual Kindergarteners

This study identifies how the contextual features of an elementary school setting shaped and often restricted bilingual kindergarten students' access to friendships within their grade-level English-dominant classroom. Data demonstrate how students utilized a teacher-designed lunch card routine to initiate, maintain, and display friendships in addition to indicating their lunch selection. Findings from the study prompted changes in my instructional practices as well as in the ESL and bilingual program design at the school in order to allow greater interaction between native English and native Spanish speakers. Implications of these findings include the significance of social relationships for language learning, for gaining status, and for motivating bilingual students to remain in school over the course of their K-12 education.     

Use of the token economy system to intervene on a school-wide level

Many writers have suggested that professionals dealing with psychological problems in school settings need to consider procedures for consulting on a system level, rather than on an individual or a group level. In this report, a token economy system was implemented for all 459 students in a K-6 elementary school. Managing an intervention program at the system level required comprehensive procedures for staff training and program modification. The results showed a major decrease in classroom disruptions and a decrease in negative teacher interactions during the token economy system compared with baseline data. Data analysis the following summer on system-wide variables demonstrated that the number of suspended students and number of days of suspension decreased, that the rate of gain on achievement tests in reading and mathematics increased compared with the yearly rates suggested by test scores the previous year, and that the teacher turnover rate decreased. Several variables considered necessary for the effective implementation of the program were discussed.