682 research outputs found

    Culturally Sustaining Math Word Problem Instruction with Hip-Hop Story Schemas

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    On August 11, 2023, Hip-Hop celebrated its 50th anniversary. In honor of this milestone, we share an activity that is designed to harness the power and art of Hip-Hop to support learning in mathematics for students with and without exceptionalities. Using a vignette, we examine why culturally sustaining practices are pivotal to learning and how teachers can collaborate with middle-school students to strengthen an evidence-based practice such as schema-based instruction by honoring the funds of knowledge that students possess. The activity includes (a) the creation of culturally relevant word problems in mathematics, (b) schema-based instruction for solving additive-type word problems, and (c) the development of Hip-Hop rhymes to communicate problem-solving math schemas. Schema-based instruction supports students’ mathematical reasoning and word-problem solving by teaching students to identify underlying problem structures and reasons for addition/subtraction or multiplication/division and is an evidence-based practice for supporting word problem solving skills for students with exceptionalities. Herein we provide a practitioner-ready guide for implementing these activities so that educators may replicate or adapt them to meet their students’ needs. Although we focus on schema-based instruction, the Hip-Hop pedagogical tools shared could be applied to enhance instruction in other academic areas

    Seasonality of birth outcomes in rural Sarlahi District, Nepal: a population-based prospective cohort

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    Background While seasonality of birth outcomes has been documented in a variety of settings, data from rural South Asia are lacking. We report a descriptive study of the seasonality of prematurity, low birth weight, small for gestational age, neonatal deaths, and stillbirths in the plains of Nepal. Methods Using data collected prospectively during a randomized controlled trial of neonatal skin and umbilical cord cleansing with chlorhexidine, we analyzed a cohort of 23,662 babies born between September 2002 and January 2006. Project workers collected data on birth outcomes at the infant’s household. Supplemental data from other studies conducted at the same field site are presented to provide context. 95% confidence intervals were constructed around monthly estimates to examine statistical significance of findings. Results Month of birth was associated with higher risk for adverse outcomes (neonatal mortality, low birthweight, preterm, and small for gestational age), even when controlling for maternal characteristics. Infants had 87% (95% CI: 27 – 176%) increased risk of neonatal mortality when born in August, the high point, versus March, the low point. Conclusion Seasonality of neonatal deaths, stillbirths, birth weight, gestational age, and small for gestational age were found in Nepal. Maternal factors, meteorological conditions, infectious diseases, and nutritional status may be associated with these adverse birth outcomes. Further research is needed to understand the causal mechanisms that explain the seasonality of adverse birth outcomes

    Infant vaccination timing: Beyond traditional coverage metrics for maximizing impact of vaccine programs, an example from southern Nepal.

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    Background Immunization programs currently measure coverage by assessing the proportion of children 12–24 months who have been immunized but this does not address the important question of when the scheduled vaccines were administered. Data capturing the timing of vaccination in first 6 months, when severe disease is most likely to occur, are limited. Objective To estimate the time to Bacillus Calmette–Guérin (BCG) (recommended at birth), diphtheria-tetanus-pertussis-H, influenza b-hepatitis B (DTP-Hib-HepB), and oral polio vaccine (OPV) (recommended at 6, 10, and 14 weeks) vaccinations and risk factors for vaccination delay in infants \u3c6 months of age in a district in southern Nepal where traditional coverage metrics are high. Design/methods Infants enrolled in a randomized controlled trial of maternal influenza vaccination were visited weekly at home from birth through age 6 months to ascertain if any vaccinations had been given in the prior week. Infant, maternal, and household characteristics were recorded. BCG, DTP-Hib-HepB, and OPV vaccination coverage at 4 and 6 months was estimated. Time to vaccination was estimated through Kaplan–Meier curves; Cox-proportional hazards models were used to examine risk factors for delay for the first vaccine. Results The median age of BCG, first OPV and DTP-Hib-HepB receipt was 22, 21, and 18 weeks, respectively. Almost half of infants received no BCG by age 6 months. Only 8% and 7% of infants had received three doses of OPV and DTP-Hib-HepB, respectively, by age 6 months. Conclusion A significant delay in receipt of infant vaccines was found in a prospective, population-based, cohort in southern Nepal despite traditional coverage metrics being high. Immunization programs should consider measuring time to receipt relative to the official schedule in order to maximize benefits for disease control and child health

    Pertussis Seroepidemiology in Women and Their Infants in Sarlahi District, Nepal.

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    Background Infants are at greatest risk for pertussis morbidity and mortality. Maternal vaccination during pregnancy has been shown to prevent pertussis in young infants in high- and middle-income countries. However, data on the levels of maternal pertussis antibodies and the efficiency of transplacental transfer in low-income South Asian settings are limited. Objective To estimate the prevalence of maternal pertussis antibodies and the efficiency of transplacental transfer in rural southern Nepal. Design/methods Paired maternal-infant blood samples were collected from a subsample of participants in a randomized, controlled trial of maternal influenza immunization (n = 291 pairs). Sera were tested by enzyme-linked immunosorbent assays for pertussis toxin, filamentous hemagglutinin, pertactin, and fimbriae. Maternal and infant pertussis antibody levels and transplacental transfer efficiency were determined and potential factors associated with both were assessed. Results Elevated maternal antibodies to pertussis toxin, suggesting recent pertussis infection, were rarely detected (4%, tested n = 305). However, paired maternal-cord sera were highly correlated across all antibodies; transplacental antibody transfer ratios for pertussis toxin were 1.14 (n = 291, 95% CI 1.07–1.20); filamentous hemagglutinin 1.10 (n = 120, 95% CI: 1.01–1.20); fimbriae 2/3 1.05 (n = 120, 95% CI: 0.96–1.15) and pertactin 0.96 (n = 289, 95% CI: 0.91–1.00). Older gestational age was associated with increased pertussis toxin and decreased fimbriae 2/3 antibody transport. Conclusions A low prevalence of maternal antibody to all four pertussis antigens was noted in Nepal, but transplacental antibody transfer was efficient. No consistent demographic factors were associated with elevated maternal antibody levels or efficiency of transplacental transfer. If an increase in infant pertussis disease burden was detected in this population, maternal immunization could be an effective intervention to prevent disease in early infancy

    Population-Based Pertussis Incidence and Risk Factors in Infants Less Than 6 Months in Nepal.

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    Background. Pertussis is estimated to cause 2 percent of childhood deaths globally and is a growing public health problem in developed countries despite high vaccination coverage. Infants are at greatest risk of morbidity and mortality. Maternal vaccination during pregnancy may be effective to prevent pertussis in young infants, but population-based estimates of disease burden in infants are lacking, particularly in low-income countries. The objective of this study was to estimate the incidence of pertussis in infants less than 6 months of age in Sarlahi District, Nepal. Methods. Nested within a population-based randomized controlled trial of influenza vaccination during pregnancy, infants were visited weekly from birth through 6 months to assess respiratory illness in the prior week. If any respiratory symptoms had occurred, a nasal swab was collected and tested with a multitarget pertussis polymerase chain reaction (PCR) assay. The prospective cohort study includes infants observed between May 2011 and August 2014. Results. The incidence of PCR-confirmed Bordetella pertussis was 13.3 cases per 1000 infant-years (95% confidence interval, 7.7–21.3) in a cohort of 3483 infants with at least 1 day of follow-up. Conclusions. In a population-based active home surveillance for respiratory illness, a low risk for pertussis was estimated among infants in rural Nepal. Nepal’s immunization program, which includes a childhood whole cell pertussis vaccine, may be effective in controlling pertussis in infants

    Directly interrogating single quantum dot labelled UvrA2 molecules on DNA tightropes using an optically trapped nanoprobe

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    AbstractIn this study we describe a new methodology to physically probe individual complexes formed between proteins and DNA. By combining nanoscale, high speed physical force measurement with sensitive fluorescence imaging we investigate the complex formed between the prokaryotic DNA repair protein UvrA2 and DNA. This approach uses a triangular, optically-trapped “nanoprobe” with a nanometer scale tip protruding from one vertex. By scanning this tip along a single DNA strand suspended between surface-bound micron-scale beads, quantum-dot tagged UvrA2 molecules bound to these ‘”DNA tightropes” can be mechanically interrogated. Encounters with UvrA2 led to deflections of the whole nanoprobe structure, which were converted to resistive force. A force histogram from all 144 detected interactions generated a bimodal distribution centered on 2.6 and 8.1 pN, possibly reflecting the asymmetry of UvrA2’s binding to DNA. These observations successfully demonstrate the use of a highly controllable purpose-designed and built synthetic nanoprobe combined with fluorescence imaging to study protein-DNA interactions at the single molecule level.</jats:p

    Real-time single-molecule imaging reveals a direct interaction between UvrC and UvrB on DNA tightropes

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    Nucleotide excision DNA repair is mechanistically conserved across all kingdoms of life. In prokaryotes, this multi-enzyme process requires six proteins: UvrA?D, DNA polymerase I and DNA ligase. To examine how UvrC locates the UvrB? DNA pre-incision complex at a site of damage, we have labeled UvrB and UvrC with different colored quantum dots and quantitatively observed their interactions with DNA tightropes under a variety of solution conditions using oblique angle fluorescence imaging. Alone, UvrC predominantly interacts statically with DNA at low salt. Surprisingly, however, UvrC and UvrB together in solution bind to form the previously unseen UvrBC complex on duplex DNA. This UvrBC complex is highly motile and engages in unbiased one-dimensional diffusion. To test whether UvrB makes direct contact with the DNA in the UvrBC?DNA complex, we investigated three UvrB mutants: Y96A, a b-hairpin deletion and D338N. These mutants affected the motile properties of the UvrBC complex, indicating that UvrB is in intimate contact with the DNA when bound to UvrC. Given the in vivo excess of UvrB and the abundance of UvrBC in our experiments, this newly identified complex is likely to be the predominant form of UvrC in the cell. Š 2013 The Author(s)

    Decline in Lung Function From Mid-to Late-Life With Central Arterial Stiffness: The Atherosclerosis Risk in Communities Study

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    We investigated the association of lung function at mid-life, later in life, and its 20-year decline, with arterial stiffness later in life. We examined 5720 Atherosclerosis Risk in Communities Study participants who attended Visits 1 (1987-1989) and 5 (2011-2013). Lung function measures were forced expiratory volume in one second (FEV1) and forced vital capacity (FVC), obtained at Visits 1, 2 (1990–1992), and 5. Central artery stiffness (carotid-femoral pulse wave velocity [cfPWV]) was measured at Visit 5. We evaluated associations of lung function with later-life central artery stiffness and cfPWV >75th percentile by multivariable linear and logistic regressions. Lung function at Visit 1 (FEV1 β: −26, 95% Confidence Interval [CI]: −48, −5; FVC β: −14, 95% CI: −32, 5) and Visit 5 (FEV1 β: −22, 95% CI: −46, 2; FVC β: −18, 95% CI: −38, 2) were inversely associated with cfPWV at Visit 5, and with odds of high cfPWV in fully adjusted models. Twenty-year decline in lung function was not associated with continuous or dichotomous measures of arterial stiffness (FEV1 β: 11, 95% CI: −46, 68; FVC β: −4, 95% CI: −52, 43). Lung function at mid-life and late-life was inversely associated with arterial stiffness in later life

    Podocalyxin in the Diagnosis and Treatment of Cancer

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    Kelly M. McNagny, Michael R. Hughes, Marcia L. Graves, Erin J. DeBruin, Kimberly Snyder, Jane Cipollone, Michelle Turvey, Poh C. Tan, Shaun McColl and Calvin D. Roskelle

    Using Threshold Concepts to generate a new understanding of teaching and learning Biology

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    Students come to tertiary institutions with misconceptions of key concepts in the disciplines they are studying. Their misconceptions commonly relate to conceptually difficult or troublesome knowledge (Perkins 1999) and can be: incomplete, contradictory, stable and highly resistant to change and remain intact despite repeated instruction at successively higher levels, being perhaps reinforced by teachers and textbooks (Driver 1983; Driver, Guesne and Tiberghien, 1985; Gabel 1994). For sometime, we have known that a range of concepts in Biology are conceptually difficult e.g. biochemical pathways, evolution and genetics (Brown 1995; Ross and Tronson 2007, Taylor 2006, 2008), but whether these are the ‘threshold concepts’ of (Meyer and Land 1995) is a question that needs to be explored further. We propose an alternative perspective where threshold crossing can be envisaged more productively as a cognitive process with students transported across a conceptual chasm or threshold. Misconceptions may then lie with an underlying ‘cognitive threshold’ and not a ‘threshold concept’ (Ross et al 2008). This current ALTC funded collaborative project involves three Australian universities and aims to identify the cognitive processes which underlie difficult Biological concepts; develop intervention strategies to improve students’ framework of conceptual understanding, in one or more related concept areas (that is, to help the students cross a conceptual threshold); test whether students can subsequently transfer this thinking process to aid their understanding of other similarly difficult concepts (that is, to see if they have learnt how to cross unfamiliar thresholds). In this paper we present the preliminary results of a survey which asked biology academics (both nationally and internationally) to identify troublesome biological concepts in their teaching, describe the cognitive process that underlies them which may determine why they are troublesome, and to identify the links they perceive with our nominated cognitive thresholds
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