Interest In Linkages Research Articles

From the Steam Engine to STEAM Education: An Experience with Pre-Service Mathematics Teachers

In this paper, we describe an educational experience in the context of the Master’s degree that is compulsory in Spain to become a secondary education mathematics teacher. Master’s students from two universities in Madrid (Spain) attended lectures that addressed—emphasizing the concourse of a dynamic geometry software package—some historical, didactic and mathematical issues related to linkage mechanisms, such as those arising in the 18th and 19th centuries during the development of the steam engine. Afterwards, participants were asked to provide three different kinds of feedback: (i) working on an assigned group task, (ii) individually answering a questionnaire, and (iii) proposing some classroom activity, imagining it would be addressed to their prospective pupils. All three issues focused on the specific topic of the attended lectures. In the framework of Mason’s reflective discourse analysis, the information supplied by the participants has been analyzed. The objective was to explore what they have learned from the experience and what their perception is of the potential interest in linkages as a methodological instrument for their future professional activity as teachers. This analysis is then the basis upon which to reflect on the opportunities (and problems) that this particular bar-joint linkages methodological approach could bring towards providing future mathematics teachers with attractive tools that would contribute to enhancing a STEAM-oriented education. Finally, the students’ answers allow us to conclude that the experience was beneficial for these pre-service teachers, both in improving their knowledge on linkages history, mathematics, industrial, technological and artistic applications, and in enhancing the use in the classroom of this very suitable STEAM context.

Interest in Clinic-Based Financial Services among Low-Income Prenatal Patients and its Association with Health-Related Social Risk Factors.

BackgroundPoverty and financial stress affect prenatal health and well-being as well as early childhood development. This study sought to examine interest in clinic-based financial services to address financial stress in low-income, Medicaid-enrolled prenatal patients and its relationship with self-reported social risks.MethodsWe conducted a cross-sectional study of patients at a large safety-net prenatal clinic. Participants completed a written survey on interest in linkage to financial services, poverty-related financial stress, difficulty affording social needs, and interest in services to address material hardships. We compared interest in financial and social needs services by level of financial stress using multivariate regression.ResultsRespondents (N = 108) were entirely Medicaid-enrolled, with a majority identifying as Hispanic/Latinx (57%) or Black/African American (20%). Sixty-four percent indicated interest in connection to any of the financial services surveyed. Interest was highest in employment (52%), savings and budgeting (49%), job training/adult education (49%), and financial counseling (48%) services. Individuals with high financial stress, compared to those with low financial stress, expressed a higher level of interest in financial services (aRR = 1.61 [95% CI 1.12-2.39]). Interest in financial services was associated with difficulty affording social needs (aRR = 2.24 [95% CI 1.33-4.43]) and interest in services addressing social needs (aRR = 1.45 [95% CI 1.13-1.92]).ConclusionIn this study of low-income, Medicaid-insured prenatal patients, there was a high degree of interest in clinic-based financial services. Integrating financial services into prenatal health care appears to be an approach that low-income patients would be interested in to directly address poverty and financial stress.

Interest in linkage to PrEP among people who inject drugs accessing syringe services; Miami, Florida.

BackgroundPeople who inject drugs (PWID) are at an increased risk for HIV infection due to injection and sexual risk behaviors. This study aims to examine PrEP knowledge, awareness, and willingness to be linked to PrEP services at a syringe services program (SSP), and examine the relationship between substance use and interest in PrEP linkage.MethodsData were collected using a cross-sectional survey of IDEA SSP clients in Miami, FL (N = 157). Based on reported substance injected, participants were classified into opioid-only injection or polysubstance injection. Socio-demographics and HIV risk were examined using Pearson’s Chi-Squared analysis. Bivariate and multivariable logistic regression models were used to test for significant correlates of interest in PrEP linkage.ResultsOnly 28.3% of PWID surveyed had previously heard of PrEP. However, 57.2% were interested in receiving more information about PrEP. In the adjusted model, people with opioid-only use were significantly less likely to report interest in being linked to PrEP.ConclusionKnowledge, awareness, and interest in being linked to PrEP were low among PWID surveyed. No participants of the study were successfully linked to PrEP services through direct referrals. Further research is needed to examine low threshold service delivery of PrEP to PWID at SSPs.

Does Village Chicken-Keeping Contribute to Young Children's Diets and Growth? A Longitudinal Observational Study in Rural Tanzania.

There is substantial current interest in linkages between livestock-keeping and human nutrition in resource-poor settings. These may include benefits of improved diet quality, through animal-source food consumption and nutritious food purchases using livestock-derived income, and hazards of infectious disease or environmental enteric dysfunction associated with exposure to livestock feces. Particular concerns center on free-roaming chickens, given their proximity to children in rural settings, but findings to date have been inconclusive. This longitudinal study of 503 households with a child under 24 months at enrolment was conducted in villages of Manyoni District, Tanzania between May 2014, and May 2016. Questionnaires encompassed demographic characteristics, assets, livestock ownership, chicken housing practices, maternal education, water and sanitation, and dietary diversity. Twice-monthly household visits provided information on chicken numbers, breastfeeding and child diarrhea, and anthropometry was collected six-monthly. Multivariable mixed model analyses evaluated associations between demographic, socioeconomic and livestock-associated variables and (a) maternal and child diets, (b) children’s height-for-age and (c) children’s diarrhea frequency. Alongside modest contributions of chicken-keeping to some improved dietary outcomes, this study importantly (and of substantial practical significance if confirmed) found no indication of a heightened risk of stunting or greater frequency of diarrhea being associated with chicken-keeping or the practice of keeping chickens within human dwellings overnight.

Hysteresis Effects During the Phase Transition in Solutions of Temperature Sensitive Polymers

It is demonstrated, for the first time,that well-known phase transitions induced by changes in temperature in solutions of polymers containing both hydrophilic and hydrophobic functional groups could be followed by noticeable hysteresis effects. A<br />well-known phase transitions accompanied by a sharp change in fluid properties, in particular its optical density can be induced by many external influences, including temperature changes occurring in the solutions of polymers containing both<br />hydrophilic and hydrophobic functional groups. Since intensification subsequent hydrophobic interactions, leading to loss of solubility of the polymer molecules, resulting, in particular, a significant increase in the turbidity of the medium and are accompanied by a pronounced hysteresis phenomena. Hysteresis phenomena in the processes of molecular-scale play an important theoretical and practical interest in linkage with the development of advanced nano-level technology. In particular, the issue of the development of molecular "trigger" switches, and other analog electronic systems, implemented on submolecular level was actively discussed. In fact, under the same physical conditions of the environment of macromolecules system can be in two different states, which resolves the issue of programming such molecules. State of these polymers depends on their way of formation and thermodynamic variables. Observed effect could be utilized directly for information recording into the structure on the basis of stimulus-sensitive macromolecular chains. In fact, it is a first step towards creating memory of quasi-biological elements.

PedWiz: a web-based tool for pedigree informatics

A novel web-based tool PedWiz that pipelines the informatics process for pedigree data is introduced. PedWiz is designed to assist researchers in the analysis of pedigree data. It provides a convenient tool for pedigree informatics: descriptive statistics, relative pairs, genetic similarity coefficients, the variance-covariance matrix for three estimated coefficients of allele identical-by-descent sharing as well as mean allele sharing, a plot of the pedigree structures, and a visualization of the identity coefficients. With a renewed interest in linkage and other family based methods, PedWiz will be a valuable tool for the analysis of family data.

Linking vegetation change, carbon sequestration and biodiversity: insights from island ecosystems in a long‐term natural experiment

Summary1. Despite recent interest in linkages between above‐ and below‐ground communities and their consequences for ecosystem processes, much remains unknown about their responses to long‐term ecosystem change. We synthesize multiple lines of evidence from a long‐term ‘natural experiment’ to illustrate how ecosystem retrogression (the decline in ecosystem process rates due to long‐term absence of major disturbance) drives vegetation change, and thus above‐ground and below‐ground carbon (C) sequestration, and communities of consumer biota.2. Our study system involves 30 islands in Swedish boreal forest that form a 5000‐year, fire‐driven retrogressive chronosequence. Here, retrogression leads to lower plant productivity and slower decomposition and a community shift from plants with traits associated with resource acquisition to those linked with resource conservation.3. We present consistent evidence that above‐ground ecosystem C sequestration declines, while below‐ground and total C storage increases linearly for at least 5000 years following fire absence. This increase is driven primarily by changes in vegetation characteristics, impairment of decomposer organisms and absence of humus combustion.4. Data from contrasting trophic groups show that during retrogression, biomass or abundance of plants and decomposer biota decreases, while that of above‐ground invertebrates and birds increases, due to different organisms accessing resources via distinct energy channels. Meanwhile, diversity measures of vascular plants and above‐ground (but not below‐ground) consumers respond positively to retrogression.5. We show that taxonomic richness of plants and above‐ground consumers are positively correlated with total ecosystem C storage, suggesting that conserving old‐growth forests simultaneously maximizes biodiversity and C sequestration. However, we find little observational or experimental evidence that plant diversity is a major driver of ecosystem C storage on the islands relative to other biotic and abiotic factors.6. Synthesis.Our study reveals that across contrasting islands differing in exposure to a key extrinsic driver (historical disturbance regime and resulting retrogression), there are coordinated responses of soil fertility, vegetation, consumer communities and ecosystem C sequestration, which all feed back to one another. It also highlights the value of well‐replicated natural experiments for tackling questions about above‐ground–below‐ground linkages over temporal and spatial scales that are otherwise unachievable.

Influence of individual body size on reproductive traits in melanopline grasshoppers (Orthoptera: Acrididae)

Body size affects many aspects of an organism's performance, including reproduction. Ecologists have shown an increased interest in linkages between body size variation and population dynamics. Fecundity in a number of insect orders is often positively correlated with body weight or structural size, but reproductive characteristics and body size are not always positively correlated, particularly in field studies. Numerous biotic and environmental factors can influence individual body size and reproduction in grasshoppers under field conditions. Intraspecific relationships between reproductive traits and individual body size in melanopline grasshoppers were examined using data from four field experiments. Significant positive correlations between body size and reproductive traits occurred in three of four field experiments involving Melanoplus sanguinipes (Fabricius) and Phoetaliotes nebrascensis (Thomas) where per capita resource availability was manipulated, with a highly significant relationship between femur length and functional ovarian follicles when statistical results were combined from all correlations. In addition, individual femur length was a significant covariate for at least one reproductive trait in three experiments. Biotic factors such as food availability and predation could be more important than body size in determining reproductive output under field conditions, but further work is required to examine under what conditions individual body size affects reproduction in grasshoppers.

Tests and estimates of allelic association in complex inheritance.

Family-based procedures such as the transmission disequilibrium test (TDT) were motivated by concern that sample-based methods to map disease genes by allelic association are not robust to population stratification, migration, and admixture. Other factors to consider in designing a study of allelic association are specification of gene action in a weakly parametric model, efficiency, diagnostic reliability for hypernormal individuals, interest in linkage and imprinting, and sibship composition. Family-based samples lend themselves to the TDT despite its inefficiency compared with cases and unrelated normal controls. The TDT has an efficiency of 1/2 for parent-offspring pairs and 2/3 for father-mother-child trios. Against cases and hypernormal controls, the efficiency is only 1/6 on the null hypothesis. Although dependent on marker gene frequency and other factors, efficiency for hypernormal controls is always greater than for random controls. Efficiency of the TDT is increased in multiplex families and by inclusion of normal sibs, approaching a case-control design with normal but not hypernormal controls. Isolated cases favor unrelated controls, and only in exceptional populations would avoidance of stratification justify a family-based design to map disease genes by allelic association.