Binary Amplitude Reflection Gratings for X-ray Shearing and Hartmann Wavefront Sensors.

New, high-coherent-flux X-ray beamlines at synchrotron and free-electron laser light sources rely on wavefront sensors to achieve and maintain optimal alignment under dynamic operating conditions. This includes feedback to adaptive X-ray optics. We describe the design and modeling of a new class of binary-amplitude reflective gratings for shearing interferometry and Hartmann wavefront sensing. Compact arrays of deeply etched gratings illuminated at glancing incidence can withstand higher power densities than transmission membranes and can be designed to operate across a broad range of photon energies with a fixed grating-to-detector distance. Coherent wave-propagation is used to study the energy bandwidth of individual elements in an array and to set the design parameters. We observe that shearing operates well over a ±10% bandwidth, while Hartmann can be extended to ±30% or more, in our configuration. We apply this methodology to the design of a wavefront sensor for a soft X-ray beamline operating from 230 eV to 1400 eV and model shearing and Hartmann tests in the presence of varying wavefront aberration types and magnitudes.

Reflective binary amplitude grating for soft x-ray shearing and Hartmann wavefront sensing.

We demonstrate a reflective wavefront sensor grating suitable for the characterization of high-quality x-ray beamlines and optical systems with high power densities. Operating at glancing incidence angles, the optical element is deeply etched with a two-level pattern of shearing interferometry gratings and Hartmann wavefront sensor grids. Transverse features block unwanted light, enabling binary amplitude in reflection with high pattern contrast. We present surface characterization and soft x-ray reflectometry of a prototype grating array to demonstrate function prior to wavefront measurement applications. A simulation of device performance is shown.

A content analysis of research on technology use for teaching mathematics to students with disabilities: word networks and topic modeling.

The purpose of this study was to conduct a content analysis of research on technology use for teaching mathematics to students with disabilities. We applied word networks and structural topic modeling of 488 studies published from 1980 to 2021. Results showed that the words "computer" and "computer-assisted instruction" had the highest degree of centrality in the 1980s and 1990s, and "learning disability" was another central word in the 2000s and 2010s. The associated word probability for 15 topics also represented technology use within different instructional practices, tools, and students with either high- or low-incidence disabilities. A piecewise linear regression with knots in 1990, 2000, and 2010 demonstrated decreasing trends for the topics of computer-assisted instruction, software, mathematics achievement, calculators, and testing. Despite some fluctuations in the prevalence in the 1980s, the support for visual materials, learning disabilities, robotics, self-monitoring tools, and word problem-solving instruction topics showed increasing trends, particularly after 1990. Some research topics, including apps and auditory support, have gradually increased in topic proportions since 1980. Topics including fraction instruction, visual-based technology, and instructional sequence have shown increasing prevalence since 2010; this increase was statistically significant for the instructional sequence topic over the past decade.

Effects of Interventions Using Virtual Manipulatives for Students With Learning Disabilities: A Synthesis of Single-Case Research.

Virtual manipulatives are interactive and dynamic visual objects on a screen, which allow students to manipulate them to construct mathematical knowledge. The purpose of this study was to synthesize the literature on interventions that used virtual manipulatives to improve the mathematics performance of K-12 students with learning disabilities. A total of 19 single-case design studies (16 peer-reviewed articles and three dissertations) were selected using specific selection criteria. Overall, students with learning disabilities demonstrated mathematical improvement after receiving interventions involving virtual manipulatives. Although many students with learning disabilities maintained and generalized the intervention effects, further research is required to verify the current findings.

Improving the Mathematics Performance of Second-Grade Students with Mathematics Difficulties through an Early Numeracy Intervention.

The purpose of this study was to determine the effects of an early numeracy Tier 2 intervention on the mathematics performance of second-grade students with persistent mathematics difficulties. Whole number content and instructional design features were used to boost performance in second-grade early numeracy concepts and skills. Researchers employed a pretest-posttest control group design with randomized assignment of 83 students to the treatment condition and 38 students to the comparison condition. The research team's mathematics interventionists delivered instruction four days per week for 20 weeks to small groups of second-grade students who were identified with persistent mathematics difficulties. Proximal and distal measures were used to determine the effects of the intervention. Findings showed that students in the treatment group outperformed students in the comparison group on the proximal measure of mathematics performance. There were no differences between groups on the problem-solving measures.

Techniques for preventing and managing tube-related complications.

BACKGROUND: The management of jejunostomy and gastrostomy tubes that are not well stabilized and leak effluent around the insertion site present significant challenges to WOC nursing practice. The result is often peritubular skin erosion, patient discomfort, and high-volume fluid losses that are not measurable. CASE: WOC nursing was consulted when a 70-year-old woman with a jejunostomy tube experienced leakage, skin erosion, and pain. A novel technique for tube stabilization and local treatment of the peritubular skin was successful in stabilizing her jejunostomy tube, protecting the skin surrounding the tube, relieving associated pain, and enabling accurate measurement of output from the tube. Alternative strategies for stabilization and treatment are discussed. CONCLUSION: The outcomes of patients who have been treated with these strategies has been improved comfort since they do not feel any tube movement and decreased pain since the skin is protected from the caustic effluent and remains healthy and intact.

Teaching reading to students with learning disabilities: Effects of combined iPad-assisted and peer-assisted instruction on oral reading fluency performance.

Students with reading learning disabilities (RLDs) often face struggles in acquiring basic reading abilities, including oral reading fluency. The current study builds on previous work that compared peer-assisted instruction (PAI) to iPad-assisted instruction (IAI) on oral reading fluency, which led to the conclusion that a combined approach may be more effective than either approach alone. A multiple baseline design was used to examine the effectiveness of a combined PAI and IAI approach on oral reading fluency of four 5th grade students with RLD. Overall, there were moderate and positive experimental effects on oral reading fluency. Student gains were similar to expectations for typically achieving students from winter to spring.

A broadly distributed toxin family mediates contact-dependent antagonism between gram-positive bacteria.

The Firmicutes are a phylum of bacteria that dominate numerous polymicrobial habitats of importance to human health and industry. Although these communities are often densely colonized, a broadly distributed contact-dependent mechanism of interbacterial antagonism utilized by Firmicutes has not been elucidated. Here we show that proteins belonging to the LXG polymorphic toxin family present in Streptococcus intermedius mediate cell contact- and Esx secretion pathway-dependent growth inhibition of diverse Firmicute species. The structure of one such toxin revealed a previously unobserved protein fold that we demonstrate directs the degradation of a uniquely bacterial molecule required for cell wall biosynthesis, lipid II. Consistent with our functional data linking LXG toxins to interbacterial interactions in S. intermedius, we show that LXG genes are prevalent in the human gut microbiome, a polymicrobial community dominated by Firmicutes. We speculate that interbacterial antagonism mediated by LXG toxins plays a critical role in shaping Firmicute-rich bacterial communities.

The Effects of a Tier 3 Intervention on the Mathematics Performance of Second Grade Students With Severe Mathematics Difficulties.

The purpose of this study was to determine the effectiveness of a systematic, explicit, intensive Tier 3 (tertiary) intervention on the mathematics performance of students in second grade with severe mathematics difficulties. A multiple-baseline design across groups of participants showed improved mathematics performance on number and operations concepts and procedures, which are the foundation for later mathematics success. In the previous year, 12 participants had experienced two doses (first and second semesters) of a Tier 2 intervention. In second grade, the participants continued to demonstrate low performance, falling below the 10th percentile on a researcher-designed universal screener and below the 16th percentile on a distal measure, thus qualifying for the intensive intervention. A project interventionist, who met with the students 5 days a week for 10 weeks (9 weeks for one group), conducted the intensive intervention. The intervention employed more intensive instructional design features than the previous Tier 2 secondary instruction, and also included weekly games to reinforce concepts and skills from the lessons. Spring results showed significantly improved mathematics performance (scoring at or above the 25th percentile) for most of the students, thus making them eligible to exit the Tier 3 intervention.

Prescription for excellence: an ostomy clinic.

Individuals scheduled for ostomy surgery and those with a new or established stoma benefit from the services of a Certified Ostomy Care Nurse or Certified Wound Ostomy Continence Nurse provided in an ostomy clinic. The clinic can provide pre- and postoperative services as well as long-term holistic care. Developing a clinic requires an organized and well thought-out plan that identifies unmet patient needs to justify the importance of this ambulatory service to facility administrators. The plan should include configuring and preparing the area where care will be provided, advertising the services offered, and determining hours, staff, policies, and procedures with particular attention paid to facility and regulatory specifications. After establishing a clinic in a large, urban, acute care hospital, patient visits averaged 33 per month and the scheduled 6 hours per week of clinic time needed to be expanded to meet the needs of those requesting appointments. Once established, patient outcomes and provider satisfaction should be recorded. Certified Ostomy Care Nurses and Certified Wound Ostomy Continence Nurses have a responsibility to inform their patients about the ostomy clinic option when it is available and clinic clinicians should continue to share the results of their efforts to proliferate the ostomy clinic concept.

A synthesis of mathematical and cognitive performances of students with mathematics learning disabilities.

The purpose of this study was to synthesize the findings from 23 articles that compared the mathematical and cognitive performances of students with mathematics learning disabilities (LD) to (a) students with LD in mathematics and reading, (b) age- or grade-matched students with no LD, and (c) mathematical-ability-matched younger students with no LD. Overall results revealed that students with mathematics LD exhibited higher word problem-solving abilities and no significant group differences on working memory, long-term memory, and metacognition measures compared to students with LD in mathematics and reading. Findings also revealed students with mathematics LD demonstrated significantly lower performance compared to age- or grade-matched students with no LD on both mathematical and cognitive measures. Comparison between students with mathematics LD and younger students with no LD revealed mixed outcomes on mathematical measures and generally no significant group differences on cognitive measures.

A comparison of the effects of reading interventions on engagement and performance for fourth-grade students with learning disabilities.

Inexpensive software applications designed to teach reading, writing, mathematics, and other academic areas have become increasingly popular. Although previous research has demonstrated the potential efficacy of such applications, there is a paucity of research that compares applications instruction (AI) with traditional teacher-directed instruction (TDI), and the relative effectiveness and efficiency of these instructional approaches remains largely unknown. This study used an alternating treatment design to compare academic engagement and outcomes (i.e., word identification and reading fluency) during an AI condition and a TDI condition for four students with learning disabilities (LD) attending a charter school. Instructional conditions (i.e., TDI, AI) were randomly alternated 7 times each, for a total of 14 instructional sessions. Results indicated that both approaches fostered high levels of engagement although students were more engaged during AI. With regard to academic performance, visual and quantitative analysis suggest that TDI was more effective than AI in terms of passage fluency and word identification. Students completed social validity rating scales to examine instructional preference. Results indicated that both approaches, TDI and AI, were popular with the students.

Effects of the Good Behavior Game on classwide off-task behavior in a high school basic algebra resource classroom.

This study investigated the effects of the Good Behavior Game (GBG) on classwide off-task behavior in two ninth-grade basic algebra resource classes. Ten students with a variety of disabilities, in two classrooms, and their special education resource teacher participated in this study. A reversal design was employed, in which the special education teacher implemented GBG compared to typical practice-algebra readiness instruction. Results showed that classwide off-task behavior decreased in the GBG conditions compared to the baseline and reversal conditions. Fidelity measures indicated that the teacher implemented GBG with fidelity. Students and the teacher rated GBG favorably. Overall findings support the use of GBG for reducing classwide off-task behavior. Implications for practice and future research directions are presented.

Early mathematics achievement trajectories: English-language learner and native English-speaker estimates, using the Early Childhood Longitudinal Survey.

This study used data from the Early Childhood Longitudinal Survey, Kindergarten Class of 1998-1999, to (a) estimate mathematics achievement trends through 5th grade in the population of students who are English-language proficient by the end of kindergarten, (b) compare trends across primary language groups within this English-language proficient group, (c) evaluate the effect of low socioeconomic status (SES) for English-language proficient students and within different primary language groups, and (d) estimate language-group trends in specific mathematics skill areas. The group of English-language proficient English-language learners (ELLs) was disaggregated into native Spanish speakers and native speakers of Asian languages, the 2 most prevalent groups of ELLs in the United States. Results of multilevel latent variable growth modeling suggest that primary language may be less salient than SES in explaining the mathematics achievement of English-language proficient ELLs. The study also found that mathematics-related school readiness is a key factor in explaining subsequent achievement differences and that the readiness gap is prevalent across the range of mathematics-related skills.