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Patterns of gene flow vary greatly among Aedes aegypti populations throughout Mexico. The populations are panmictic along the Pacific coast, isolated by distance in northeast Mexico, and exhibit moderate gene flow across the Yucatan peninsula. Nine Ae. aegypti collections from 6 cities in Oaxaca, Mexico, were taken to examine the local patterns of gene flow. Genetic variation was examined in a 387-bp region of the nicotinamide adenine dinucleotide dehydrogenase subunit 4 mitochondrial gene (ND4) using single-strand conformation polymorphism analysis, and 3 haplotypes were detected. Cluster analysis on the linearized FST genetic distances failed to group collections in geographic proximity. Regression analysis of linear or road distances on linearized FST indicated that proximal collections were as diverse as distant collections across an ∼800-km range. The geographical distribution of the Mexican mosquito haplotype frequencies was determined for the ND4 sequences from 524 individuals from Oaxaca (this study) and 2,043 individuals from our previous studies. Herein, we report on yet another pattern dominated by genetic drift among 9 Ae. aegypti collections from 6 cities in Oaxaca, Mexico, and compare it to those reported in other regions of Mexico. Molecular analysis of variance showed that there was as much genetic variation among collections 4 km apart as there was among all collections. The numbers of haplotypes and the amount of genetic diversity among the collections from Oaxaca were much lower than detected in previous studies in other regions of Mexico and may reflect the effects of control efforts or adaptations to the altitudinal limits (1,500 m) of the species in Mexico. The geographical distribution of mosquito haplotypes in Mexico is also reported. Furthermore, based on the distribution of the mosquito haplotypes in America, we suggest that mosquito dispersion is very efficient, most likely due to commercial transportation. [ABSTRACT FROM AUTHOR]

Haemagglutinins have been isolated from two red marine algae Bryothamnion seaforthii and B. triquetrum, which were harvested from the Caribbean Sea, Falcon State, Venezuela. The mass spectra of the haemagglutinins isolated from B. seaforthii showed five monomer peaks (9057.4–9088.8 Da) and those from B. triquetrum showed three peaks (8981.5–8990.2 Da). Isoelectric focusing, under denaturing conditions, gave rise to multiple bands for the haemagglutinins of both species but only one band was observed under native conditions. Gel permeation experiments suggest that the monomer haemagglutinins can readily associate to form dimers, trimers and tetramers. The haemagglutinins agglutinate papainized human A, B and O erythrocytes; the activity is inhibited by glycoconjugates, but not by simple sugars, and is maintained after heating to temperatures up to 90°C. The amino acid sequence of the haemagglutinin from B. seaforthii has been determined together with a partial sequence for that from B. triquetrum. The isolation, and some characterization, of haemagglutinins from B. seaforthii and B. triquetrum, collected from the Ceara coast of Brazil, have previously been reported. Some differences and similarities of these macromolecules obtained from the two different locations are discussed. [ABSTRACT FROM AUTHOR]

The Cambrian transgression across the Great Unconformity produced one of the largest expansions of shallow marine habitats and associated diversification of marine invertebrate faunas in Earth history. However, identification of the underlying controls on the pattern of transgression of Cambrian seas has been hampered by imprecise or inaccurate age assignments for many formations. Recovery of an Ehmaniella Zone trilobite fauna from the Lodore Formation in northwestern Colorado (United States) revises the age of this unit to be signifi- cantly older, specifically middle Miaolingian (upper Wuliuan). This expands the established distribution of thick Miaolingian deposits of the northern Rocky Mountains to within 90 km of a broad region of central Colorado where Miaolingian strata are missing and Furongian successions rest directly on basement. The boundary between these two regions marks the position of an 200 km east-west offset within the generally north-south--trending Cambrian paleoshoreline of western North America. The offset is co-located with a Precambrian continental suture zone (Cheyenne belt) at the northern Yavapai terrane margin and is directly east of an offset of similar magnitude and latitude in the early to middle Paleozoic shelf edge in Nevada. We thus posit that Precambrian deep-seated crustal-scale features controlled the Cambrian paleotopography of western Laurentia, strongly influencing the patterns of Cambrian transgression and structure of the shallow marine ecosystem established during continental submergence. These continental-scale structural elements remained a major control on marine paleogeography for >200 m.y. into the late Paleozoic. [ABSTRACT FROM AUTHOR]

A response by Sian L. Beilock and Gerardo Ramirez to a letter to the editor about their article "Writing About Testing Worries Boosts Exam Performance in the Classroom" in the January 14, 2011 issue.

To evaluate medication abortion (MAB) outcomes for participants receiving intramuscular depot medroxyprogesterone acetate (DMPA) injections or subdermal etonogestrel implants concurrently with mifepristone compared to those who did not in a real-world setting. This retrospective cohort study included MAB patients from one Planned Parenthood health center in St. Paul, MN, between 2017 and 2019. We abstracted electronic health records and compared sociodemographic variables, clinical information, and treatment failure rates (primary outcome) between study groups with logistic regression (generating odds ratios [OR] and 95% confidence intervals [CI]). Among 7296 MAB participants, 224 (3.1%) received DMPA injections and 309 (4.2%) received etonogestrel implants concurrently with mifepristone; 141 (62.9%) and 200 (64.7%) completed follow-up respectively. From a random sample of 1000, 990 comparison participants met inclusion criteria; 704 (71.1%) completed follow-up. Fourteen (9.9%) DMPA participants (aOR 4.26, 95% CI 1.87–9.68, p < 0.001) and 6 (3.0%) etonogestrel implant participants (aOR 1.38, 95% CI 0.48–3.55, p = 0.522) required additional treatment to empty the uterus and/or had an ongoing pregnancy, each contrasted with 15 (2.1%) comparison patients (models adjusted for gestational duration, patient age, parity, and race). Although our study is limited by high rates of loss to follow-up, our analysis suggests that concurrent administration of DMPA with mifepristone may decrease MAB efficacy, while etonogestrel implant placement does not appear to alter MAB outcomes. These findings are overall consistent with prior literature and inform post-MAB contraception counseling. This retrospective cohort study reinforces prior randomized controlled trial findings that concurrent depot medroxyprogesterone acetate injection with mifepristone administration may decrease medication abortion efficacy. Conversely, concurrent etonogestrel contraceptive implant placement with mifepristone administration does not appear to decrease medication abortion efficacy. These findings inform post-abortion contraception counseling. [ABSTRACT FROM AUTHOR]

This paper presents an experimental platform for regulating the DC motor angular speed powered by photovoltaic cells. The experimental platform comprises an Eco Green Energy EGE-260P-60 solar panel, DC/DC SEPIC converter, DC bus, DC/DC buck converter, DC motor and Nexys 4 board with an Artix-7 100T FPGA. The DC/DC SEPIC converter is used for harvesting the maximum amount of energy from the PV cells using the perturb and observe algorithm to track the maximum power point. The DC/DC buck converter is used as the motor drive using the active disturbance rejection control to regulate the angular speed of the DC motor. In addition, the FPGA architecture design is presented using a hierarchical top-down methodology with the VHDL hardware description language and Xilinx System Generator tool. The software takes advantage of the FPGA's concurrency to simultaneously evaluate the different processes, which is the main reason for choosing this digital device. Several tests were performed on the platform such as irradiance changes, DC bus variations, DC motor connection and load torque variations applied in the motor shaft. The results indicate that the maximum power is obtained from the photovoltaic cells, establishing the minimum operating conditions. In addition, the control approach estimates and cancels the effects of disturbances caused by variations in the environmental conditions, photovoltaic system, DC bus, and load changes in order to regulate DC motor speed. [ABSTRACT FROM AUTHOR]

People's fear and anxiety about doing math-over and above actual math ability-can be an impediment to their math achievement. We show that when the math-anxious individuals are female elementary school teachers, their math anxiety carries negative consequences for the math achievement of their female students. Early elementary school teachers in the United States are almost exclusively female (>90%), and we provide evidence that these female teachers' anxieties relate to girls' math achievement via girls' beliefs about who is good at math. First- and second-grade female teachers completed measures of math anxiety. The math achievement of the students in these teachers' classrooms was also assessed. There was no relation between a teachers math anxiety and her students' math achievement at the beginning of the school year. By the school years end, however, the more anxious teachers were about math, the more likely girls (but not boys) were to endorse the commonly held stereotype that "boys are good at math, and girls are good at reading" and the lower these girls' math achievement. Indeed, by the end of the school year, girls who endorsed this stereotype had significantly worse math achievement than girls who did not and than boys overall. In early elementary school, where the teachers are almost all female, teachers' math anxiety carries consequences for girls' math achievement by influencing girls' beliefs about who is good at math. [ABSTRACT FROM AUTHOR]

The purpose of this study is to critically and systematically examine current discourse within scholarship on the internationalization of higher education. Our study engages critical discourse analysis to review articles from four top-tier higher education academic journals published between 2000 and 2016. Findings across journals/articles demonstrate the absence of a clear definition of the concept of internationalization, a strong Western focus, and often inexplicit recommendations for practical application of research findings. Through critical discourse analysis, we explore the orientation of higher education research towards equity and inclusivity and challenge the perception of international higher education research and its distribution through academic journals as value-neutral. By continuing to recognize, articulate, and critique biases in research development and dissemination, higher education researchers and discourse may become more accountable and continue to develop a more critical lens for promoting globally inclusive scholarship. This study contributes to the ways in which discourse both shapes and is shaped by knowledge production in the higher education landscape, and future directions for this field. [ABSTRACT FROM AUTHOR]

Precise sedimentological, stratigraphic, paleontological, and geochronological data collected from Paleozoic strata of the Dinosaur National Monument (DNM) area (NW Colorado and NE Utah) allow for comprehensive revision of the depositional history of that part of the central Rocky Mountains. Recovery of multiple species of the trilobite genus Elrathiella from sandstone beds in the middle of the Lodore Formation assigns those deposits to the mid-Miaolingian Ehmaniella Zone near the top of the Wuliuan Stage. This is significantly older than the previous "Dresbachian" age estimate for those coarse clastics, which attributed them to deposition during the late Miaolingian (latest Drumian or Guzhangian). This age revision re-positions the southernmost boundary of widespread Miaolingian inner detrital belt deposits of Wyoming to within 90 km of an extensive area of central Colorado where strata of this age are absent, and middle Furongian successions rest directly on basement. The boundary between these two regions, one with and one without Miaolingian strata, is nearly coincident with the Cheyenne belt, an east–west oriented Precambrian continental suture zone at the northern margin of the Yavapai Terrane. This association supports the idea that deep-seated crustal-scale features controlled the Cambrian paleotopography of the Rocky Mountain region and, in turn, the regional pattern of Cambrian transgression across western Laurentia. Early cursory paleontological work suggested a Devonian age for a thick sandstone interval near the top of the Lodore Formation, based on phosphatic fossils. We demonstrate that these fossils are in fact Cambrian obolid brachiopod shells. However, we provide multiple lines of evidence, including carbonate δ13C chemostratigraphic data, distinctive lithofacies, and stratigraphic relationships to argue that a thin interval of shale and dolostone, as well as a previously unrecognized paleokarst and regolith interval at the top of what was mapped as Lodore Formation, are in fact part of the Upper Devonian Parting Formation. The thick sub-Mississippian paleoregolith is consistent with elevated rates of weathering during the Late Devonian–Early Mississippian. δ13C chemostratigraphic data for the Madison Limestone include a large double-peaked Kinderhookian positive isotopic excursion (up to ~6.5 ‰), providing a precise estimate of the timing of Mississippian transgression in this part of the Rocky Mountain region. Detrital zircon geochronologic data for Cambrian to Pennsylvanian strata show remarkably consistent patterns dominated by ~1100 Ma, ~1400 Ma, and ~1700 Ma peaks, reflecting relative igneous quiescence over much of the Paleozoic for this region, a span of ~200 m.y., despite some orogenic activity (e.g., Antler Orogeny, Ancestral Rockies) during that time interval. [ABSTRACT FROM AUTHOR]

In the United States, Salmonella enterica ser. Enteritidis (SE) is among the leading bacterial cause of foodborne illness via consumption of raw or undercooked eggs. The top Salmonella serovars implicated in U.S. foodborne outbreaks associated with chicken consumption include SE, Typhimurium (ST), Heidelberg (SH), Montevideo, Mbandka, Braenderup, and Newport. While enforcement actions target the eradication of SE from layer hens, there is a growing concern that other serovars could occupy this niche and be a cause of egg-transmitted human salmonellosis. Therefore, we tested the invasion and survival of SE, SH, ST, and Salmonella enterica ser. Hadar (S. Hadar) at 4 and 20 h post infection (hpi) in chicken ovarian granulosa cells (cGC); a cellular layer which surrounds the previtelline layer and central yolk in egg-forming follicles. We also evaluated cGC transcriptional changes, using an antibacterial response PCR array, to assess host response to intracellular Salmonella. We observed that invasion of cGC by SE, SH, and ST was significantly higher than invasion by S. Hadar, with ST showing the highest level of invasion. The Bacterial Survival Index, defined as the ratio of intracellular bacteria at 20 and 4 h, were 18.94, 7.35, and 15.27 for SE, SH, and ST, respectively, with no significant difference in survival between SE or ST compared to SH. Evaluation of cGC anti-Salmonella gene responses indicated that at 4 hpi there was a significant decrease in Toll-like receptor (TLR)-4 mRNA in cGC infected with SE, whereas TLR5 and myeloid differentiation primary response gene 88 were significantly down regulated across all serovars. At 4 hpi, invasion by Salmonella serovars resulted in significant upregulation of several antimicrobial genes, and proinflammatory cytokines and chemokines (PICs). At 20 hpi, all the serovars induced PICs with SH being the strongest inducer. Additionally, SE, SH and ST differentially induced signal transduction pathways. Although only a single strain from each serovar was tested, cGC presents a useful ex vivo cell culture model to assess the virulence potential of Salmonella serovars. [ABSTRACT FROM AUTHOR]

• Higher-math-anxious parents report feeling more negative emotions during math homework-help. • These relations are not due to differences in math ability or general anxiety. • These findings have important implications for educational practices and policy. In two separate studies, we examined the relation between parents' math anxiety and their perceptions of their math homework-helping interactions with their children. Specifically, we surveyed parents of children in Grades 1–6 across North America on the time they spend helping their child with their math homework and the level of confidence, conflict, stress, frustration, and emotionality that they feel during math homework interactions as a function of their math anxiety. As predicted, parents who were higher in math anxiety reported feeling a more negative emotional experience surrounding the homework environment when helping their child with math homework. Understanding this dynamic has important implications for educational practices, especially given the push for parents to be involved in their children's learning. [ABSTRACT FROM AUTHOR]

Women reliably perform worse than men on measures of spatial ability, particularly those involving mental rotation. At the same time, females also report higher levels of spatial anxiety than males. What remains unclear, however, is whether and in what ways gender differences in these cognitive and affective aspects of spatial processing may be interrelated. Here, we tested for robust gender differences across six different datasets in spatial ability and spatial anxiety (N = 1257, 830 females). Further, we tested for bidirectional mediation effects. We identified indirect relations between gender and spatial skills through spatial anxiety, as well as between gender and spatial anxiety through spatial skills. In the gender → spatial anxiety → spatial ability direction, spatial anxiety explained an average of 22.4% of gender differences in spatial ability. In the gender → spatial ability → spatial anxiety direction, spatial ability explained an average of 25.9% of gender differences in spatial anxiety. Broadly, these results support a strong relation between cognitive and affective factors when explaining gender differences in the spatial domain. However, the nature of this relation may be more complex than has been assumed in previous literature. On a practical level, the results of this study caution the development of interventions to address gender differences in spatial processing which focus primarily on either spatial anxiety or spatial ability until such further research can be conducted. Our results also speak to the need for future longitudinal work to determine the precise mechanisms linking cognitive and affective factors in spatial processing.

Relativistic calculations of the structural and spectral properties of the PbO molecule can provide fundamental information about the importance of a proper treatment of angular momentum coupling among electrons in order to achieve accurate computational results for spectral properties. Specifically, the nature of these couplings in PbO is expected to be intermediate between the LS - and jj -coupling limits because of its light/heavy element composition. This article reports potential energy curves, transition energies, electric dipole transition moments, permanent dipole moments and spectroscopic constants of PbO calculated using a multireference single plus double excitations spin-orbit configuration interaction approach in the context of relativistic effective core potentials and their concomitant spin-orbit coupling operators. The calculated results are in general agreement with both available experimental results as well as earlier calculations. New values for properties of excited states are also reported. It is noteworthy that certain properties show larger deviations from previous calculations. These deviations are attributed to direct and indirect relativistic effects resulting from diatomic electron-electron angular momentum coupling effects, which are included consistently in the calculations reported herein., (© 2022 IOP Publishing Ltd.)

Background: Traditional math instruction that emphasizes procedures and rote memorization is common in math classes, particularly within the United States. Students may be able to perform steps and recite information, but flexible thinking in math is also an important ability. Lay theories assume that extensive experience in math would lead to increased flexibility, but some research has posited a change-resistant account, which argues that experience with traditional instruction may make it difficult to think flexibly about even simple concepts., Aims: The current study explored the mathematical flexibility of college students who completed their K-12 education in the United States, and investigated how affective and cognitive factors contributed to flexible thinking., Sample: Participants were 128 undergraduate students at a competitive U.S. public university., Method: Mathematical flexibility was measured through a novel task that asked participants to generate as many strategies as they could for a simple arithmetic problem. These strategies were coded to create scores of fluency (number of strategies) and flexibility (number of unique strategies)., Results and Conclusions: On average, participants were only able to provide little more than three unique strategies beyond the primary strategy taught in K-12 classrooms. Measures of math anxiety, math identity, need for cognition, and working memory were all unrelated to flexibility. However, student perceptions of how many possible solutions exist were significantly related to flexibility. These results provide evidence for a change-resistance account and provide further evidence that math flexibility is a unique construct., (© 2020 The British Psychological Society.)

In this study, we assessed the impact of providing students with short video clips highlighting the relevance of material they are learning in the genetics classroom to their everyday lives. These interesting but non-learning objective oriented clips, referred to as "seductive details," have been studied extensively in laboratory contexts. In laboratory studies, seductive details have been shown to actually decrease learning, leading some to recommend that any information not directly pertaining to academic learning outcomes be removed from education materials. We aimed to uncover effects of seductive details in an actual college course, in a manner divorced from the confounding variation introduced by instructor-level differences in personality and lecture styles. Our results show that, in a flipped-classroom environment, seductive details do not harm students' content attainment, interest, or perceived learning, but they are memorable. Students with high background knowledge of genetics reported greater learning after watching videos containing seductive details than students who watched equivalent videos without seductive details, but there was no difference in quiz scores between the groups. These results contradict some of the major effects observed throughout decades of studies conducted in artificial psychology laboratory environments and highlight possible affective benefits of instructors using seductive details.

Gender gaps in exam scores or final grades are common in introductory college science and engineering classrooms, with women underperforming relative to men with the same admission test scores or college grade point averages. After failing to close a historically documented gender gap in a large introductory biology course using interventions targeted at training a growth mindset, we implemented interventions designed to reduce student test anxiety. We combined evidence-based exercises based on expressive writing and on reappraising physiological arousal. We also used a valid measure to quantify test anxiety at the start and end of the course. This instrument measures an individual's self-declared or perceived test anxiety-also called trait anxiety-but not the immediate or "state" anxiety experienced during an actual exam. Consistent with previous reports in the literature, we found that women in this population declared much higher test anxiety than men and that students who declared higher test anxiety had lower exam scores than students who declared lower test anxiety. Although the test anxiety interventions had no impact on the level of self-declared trait anxiety, they did significantly increase student exam performance. The treatment benefits occurred in both men and women. These data suggest that 1) a combination of interventions based on expressive writing and reappraising physiological arousal can be a relatively easy manner to boost exam performance in a large-enrollment science, technology, engineering, and mathematics (STEM) course and encourage emotion regulation; 2) women are more willing than men to declare that they are anxious about exams, but men and women may actually experience the same level of anxiety during the exam itself; and 3) women are underperforming in STEM courses for reasons other than gender-based differences in mindset or test anxiety.

Educational attainment is one lever that can increase opportunity for economically disadvantaged families-especially in Science, Technology, Engineering, and Math (STEM). Unfortunately, students from lower-income backgrounds often perform poorly and fail high school STEM courses, which are a necessary step in pursuing fast-growing and lucrative STEM careers, graduating high school, and matriculating to college. We reasoned that, because high school STEM courses often use high-stakes tests to gauge performance, and such tests can be especially stressful for lower-income students, interventions that help students regulate their negative emotions during tests should reduce the achievement gap between higher- and lower-income students. In a large-scale ( n = 1,175) field experiment conducted in ninth grade science classrooms, students were asked to complete a control exercise, or they were given the opportunity to complete an exercise to help them regulate their worries and reinterpret their anxious arousal before their tests. We found significant benefits of emotion regulation activities for lower-income students in terms of their science examination scores, science course passing rate, and students' attitudes toward examination stress, suggesting that students' emotions are one factor that impacts performance. For example, 39% of lower-income students failed the course in the control group compared with only 18% of students failing the course if they participated in the emotion regulation interventions-a reduction in course failure rate by half. Our work underscores the crucial importance of targeting students' emotions during impactful points in their academic trajectories for improving STEM preparedness and enhancing overall academic success., Competing Interests: The authors declare no conflict of interest., (Copyright © 2019 the Author(s). Published by PNAS.)

Elementary school teachers' math anxiety has been found to play a role in their students' math achievement. The current study addresses the role of teacher math anxiety on ninth-grade students' math achievement and the mediating factors underlying this relationship. Using data from the National Mindset Study, we find that higher teacher math anxiety is associated with lower math achievement. This relationship is partially mediated by the students' perception that their teacher believes not everyone can be good at math and is not explainable by teachers' usable knowledge to teach mathematics. In subsequent analyses, we find that higher teacher math anxiety relates to a reduction in process-oriented (as opposed to ability-oriented) teaching practices, which in turn predict students' perception of teacher mindset. We argue that math anxious teachers and their use of particular teaching strategies have the potential to shape students' math achievement and their perceptions of what their teacher believes about math.

Even at young ages, children self-report experiencing math anxiety, which negatively relates to their math achievement. Leveraging a large dataset of first and second grade students' math achievement scores, math problem solving strategies, and math attitudes, we explored the possibility that children's math anxiety (i.e., a fear or apprehension about math) negatively relates to their use of more advanced problem solving strategies, which in turn relates to their math achievement. Our results confirm our hypothesis and, moreover, demonstrate that the relation between math anxiety and math problem solving strategies is strongest in children with the highest working memory capacity. Ironically, children who have the highest cognitive capacity avoid using advanced problem solving strategies when they are high in math anxiety and, as a result, underperform in math compared with their lower working memory peers., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A large field study of children in first and second grade explored how parents' anxiety about math relates to their children's math achievement. The goal of the study was to better understand why some students perform worse in math than others. We tested whether parents' math anxiety predicts their children's math achievement across the school year. We found that when parents are more math anxious, their children learn significantly less math over the school year and have more math anxiety by the school year's end-but only if math-anxious parents report providing frequent help with math homework. Notably, when parents reported helping with math homework less often, children's math achievement and attitudes were not related to parents' math anxiety. Parents' math anxiety did not predict children's reading achievement, which suggests that the effects of parents' math anxiety are specific to children's math achievement. These findings provide evidence of a mechanism for intergenerational transmission of low math achievement and high math anxiety., (© The Author(s) 2015.)

Two laboratory and two randomized field experiments tested a psychological intervention designed to improve students' scores on high-stakes exams and to increase our understanding of why pressure-filled exam situations undermine some students' performance. We expected that sitting for an important exam leads to worries about the situation and its consequences that undermine test performance. We tested whether having students write down their thoughts about an upcoming test could improve test performance. The intervention, a brief expressive writing assignment that occurred immediately before taking an important test, significantly improved students' exam scores, especially for students habitually anxious about test taking. Simply writing about one's worries before a high-stakes exam can boost test scores.