Examining arts education policy development through policy frameworks

ABSTRACT

While policy formation frameworks are commonly used to understand public policy developments, scholars rarely have used them to reflect on arts education policies. Such analysis is important because it can assist both in identifying the genesis of past policies, including who the important actors are, how issues are framed and problematized, and how specific solutions are designed, as well as how to interpret unfolding policies. In this article, I review three prominent policy frameworks: Kingdon's “multiple streams framework,” Sabatier and Jenkins-Smith's “advocacy coalition framework,” and Baumgartner and Jones' “punctuated equilibrium framework.” After reviewing the frameworks, I address the following questions: (a) How would these conceptual frameworks predict arts education policy development to proceed? (b) How would these conceptual frameworks explain constituents and coalitions that affect the arts education policy sphere? (c) How would these conceptual frameworks illuminate precipitating events that drive the policy development process? I apply the frameworks to several instances of arts education policy development, including the formal designation of the arts as a core subjects under the Goals 2000: Educate America Act of 1994 (P.L. 103-227), the development of the 2014 National Core Arts Standards, and music's enumeration in the Every Student Succeeds Act of 2015. Because these three policy issues differ in important ways, they can help to illuminate the breadth of arts education policy.     

The genetic basis of developmental abnormalities in interpopulation hybrids of the moss Ceratodon purpureus

Divergent populations are intrinsically reproductively isolated when hybrids between them either fail to develop properly or do not produce viable offspring. Intrinsic isolation may result from Dobzhansky-Muller (DM) incompatibilities, in which deleterious interactions among genes or gene products lead to developmental problems or underdominant chromosome structure differences between the parents. These mechanisms can be tested by studying marker segregation patterns in a hybrid mapping population. Here we examine the genetic basis of abnormal development in hybrids between two geographically distant populations of the moss Ceratodon purpureus. Approximately half of the hybrid progeny exhibited a severely reduced growth rate in early gametophyte development. We identified four unlinked quantitative trait loci (QTL) that interacted asymmetrically to cause the abnormal development phenotype. This pattern is consistent with DM interactions. We also found an excess of recombination between three marker pairs in the abnormally developing progeny, relative to that estimated in the normal progeny. This suggests that structural differences in these regions contribute to hybrid breakdown. Two QTL coincided with inferred structural differences, consistent with recent theory suggesting that rearrangements may harbor population divergence alleles. These observations suggest that multiple complex genetic factors contribute to divergence among populations of C. purpureus.     

Maximizing antibody production in a targeted integration host by optimization of subunit gene dosage and position

Historically, therapeutic protein production in Chinese hamster ovary (CHO) cells has been accomplished by random integration (RI) of expression plasmids into the host cell genome. More recently, the development of targeted integration (TI) host cells has allowed for recombination of plasmid DNA into a predetermined genomic locus, eliminating one contributor to clone-to-clone variability. In this study, a TI host capable of simultaneously integrating two plasmids at the same genomic site was used to assess the effect of antibody heavy chain and light chain gene dosage on antibody productivity. Our results showed that increasing antibody gene copy number can increase specific productivity, but with diminishing returns as more antibody genes are added to the same TI locus. Random integration of additional antibody DNA copies in to a targeted integration cell line showed a further increase in specific productivity, suggesting that targeting additional genomic sites for gene integration may be beneficial. Additionally, the position of antibody genes in the two plasmids was observed to have a strong effect on antibody expression level. These findings shed light on vector design to maximize production of conventional antibodies or tune expression for proper assembly of complex or bispecific antibodies in a TI system.     

A New Player in the Spermiogenesis Pathway of Caenorhabditis elegans

Precise timing of sperm activation ensures the greatest likelihood of fertilization. Precision in Caenorhabditis elegans sperm activation is ensured by external signaling, which induces the spherical spermatid to reorganize and extend a pseudopod for motility. Spermatid activation, also called spermiogenesis, is prevented from occurring prematurely by the activity of SPE-6 and perhaps other proteins, termed “the brake model.” Here, we identify the spe-47 gene from the hc198 mutation that causes premature spermiogenesis. The mutation was isolated in a suppressor screen of spe-27(it132ts), which normally renders worms sterile, due to defective transduction of the activation signal. In a spe-27(+) background, spe-47(hc198) causes a temperature-sensitive reduction of fertility, and in addition to premature spermiogenesis, many mutant sperm fail to activate altogether. The hc198 mutation is semidominant, inducing a more severe loss of fertility than do null alleles generated by CRISPR-associated protein 9 (Cas9) technology. The hc198 mutation affects an major sperm protein (MSP) domain, altering a conserved amino acid residue in a β-strand that mediates MSP–MSP dimerization. Both N- and C-terminal SPE-47 reporters associate with the forming fibrous body (FB)-membranous organelle, a specialized sperm organelle that packages MSP and other components during spermatogenesis. Once the FB is fully formed, the SPE-47 reporters dissociate and disappear. SPE-47 reporter localization is not altered by either the hc198 mutation or a C-terminal truncation deleting the MSP domain. The disappearance of SPE-47 reporters prior to the formation of spermatids requires a reevaluation of the brake model for prevention of premature spermatid activation.     

Sex-biased dispersal and the speed of two-sex invasions

Population models that combine demography and dispersal are important tools for forecasting the spatial spread of biological invasions. Current models describe the dynamics of only one sex (typically females). Such models cannot account for the sex-related biases in dispersal and mating behavior that are typical of many animal species. In this article, we construct a two-sex integrodifference equation model that overcomes these limitations. We derive an explicit formula for the invasion speed from the model and use it to show that sex-biased dispersal may significantly increase or decrease the invasion speed by skewing the operational sex ratio at the invasion's low-density leading edge. Which of these possible outcomes occurs depends sensitively on complex interactions among the direction of dispersal bias, the magnitude of bias, and the relative contributions of females and males to local population growth.     

Placenta growth factor-1 exerts time-dependent stabilization of adherens junctions following VEGF-induced vascular permeability

Increased vascular permeability is an early event characteristic of tissue ischemia and angiogenesis. Although VEGF family members are potent promoters of endothelial permeability the role of placental growth factor (PlGF) is hotly debated. Here we investigated PlGF isoforms 1 and 2 and present in vitro and in vivo evidence that PlGF-1, but not PlGF-2, can inhibit VEGF-induced permeability but only during a critical window post-VEGF exposure. PlGF-1 promotes VE-cadherin expression via the trans-activating Sp1 and Sp3 interaction with the VE-cadherin promoter and subsequently stabilizes transendothelial junctions, but only after activation of endothelial cells by VEGF. PlGF-1 regulates vascular permeability associated with the rapid localization of VE-cadherin to the plasma membrane and dephosphorylation of tyrosine residues that precedes changes observed in claudin 5 tyrosine phosphorylation and membrane localization. The critical window during which PlGF-1 exerts its effect on VEGF-induced permeability highlights the importance of the translational significance of this work in that PLGF-1 likely serves as an endogenous anti-permeability factor whose effectiveness is limited to a precise time point following vascular injury. Clinical approaches that would pattern nature's approach would thus limit treatments to precise intervals following injury and bring attention to use of agents only during therapeutic windows.     

Morphologically cryptic biological species within the liverwort Frullania asagrayana

? Premise of the study: The Frullania tamarisci complex includes eight Holarctic liverwort species. One of these, F. asagrayana, is distributed broadly throughout eastern North America from Canada to the Gulf Coast. Preliminary genetic data suggested that the species includes two groups of populations. This study was designed to test whether the two groups are reproductively isolated biological species. ? Methods: Eighty-eight samples from across the range of F. asagrayana, plus 73 samples from one population, were genotyped for 13 microsatellite loci. Sequences for two plastid loci and nrITS were obtained from 13 accessions. Genetic data were analyzed using coalescent models and Bayesian inference. ? Key results: Frullania asagrayana is sequence-invariant at the two plastid loci and ITS2, but two clear groups were resolved by microsatellites. The two groups are largely reproductively isolated, but there is a low level of gene flow from the southern to the northern group. No gene flow was detected in the other direction. A local population was heterogeneous but displayed strong genetic structure. ? Conclusions: The genetic structure of F. asagrayana in eastern North America reflects morphologically cryptic differentiation between reproductively isolated groups of populations, near-panmixis within groups, and clonal propagation at local scales. Reproductive isolation between groups that are invariant at the level of nucleotide sequences shows that caution must be exercised in making taxonomic and evolutionary inferences from reciprocal monophyly (or lack thereof) between putative species.     

Antibody Specificities Associated with Neutralization Breadth in Plasma from Human Immunodeficiency Virus Type 1 Subtype C-Infected Blood Donors

Defining the specificities of the anti-human immunodeficiency virus type 1 (HIV-1) envelope antibodies able to mediate broad heterologous neutralization will assist in identifying targets for an HIV-1 vaccine. We screened 70 plasmas from chronically HIV-1-infected individuals for neutralization breadth. Of these, 16 (23%) were found to neutralize 80% or more of the viruses tested. Anti-CD4 binding site (CD4bs) antibodies were found in almost all plasmas independent of their neutralization breadth, but they mainly mediated neutralization of the laboratory strain HxB2 with little effect on the primary virus, Du151. Adsorption with Du151 monomeric gp120 reduced neutralizing activity to some extent in most plasma samples when tested against the matched virus, although these antibodies did not always confer cross-neutralization. For one plasma, this activity was mapped to a site overlapping the CD4-induced (CD4i) epitope and CD4bs. Anti-membrane-proximal external region (MPER) (r = 0.69; P < 0.001) and anti-CD4i (r = 0.49; P < 0.001) antibody titers were found to be correlated with the neutralization breadth. These anti-MPER antibodies were not 4E10- or 2F5-like but spanned the 4E10 epitope. Furthermore, we found that anti-cardiolipin antibodies were correlated with the neutralization breadth (r = 0.67; P < 0.001) and anti-MPER antibodies (r = 0.6; P < 0.001). Our study suggests that more than one epitope on the envelope glycoprotein is involved in the cross-reactive neutralization elicited during natural HIV-1 infection, many of which are yet to be determined, and that polyreactive antibodies are possibly involved in this phenomenon.The generation of an antibody response capable of neutralizing a broad range of viruses remains an important goal of human immunodeficiency virus type 1 (HIV-1) vaccine development. Despite multiple efforts in the design of immunogens capable of inducing such humoral responses, little progress has been made (18, 20, 39). The sequence variability of the virus, as well as masking mechanisms exhibited by the envelope glycoprotein, has further hindered this pursuit (6, 22). It is known that while the majority of HIV-infected individuals mount a strong neutralization response against their own virus within the first 6 to 12 months of infection, breadth is observed in only a few individuals years later (5, 10, 15, 26, 33, 40, 41). However, very little is known about the specificities of the antibodies that confer this broad cross-neutralization. It is plausible that broadly cross-neutralizing (BCN) plasmas contain antibodies that target conserved regions of the envelope glycoprotein, as exemplified by a number of well-characterized broadly neutralizing monoclonal antibodies (MAbs). The b12 MAb recognizes the CD4 binding site (CD4bs), and 2G12 binds to surface glycans (7, 42, 44, 56). The 447-52D MAb recognizes the V3 loop, and 17b, E51, and 412d bind to CD4-induced (CD4i) epitopes that form part of the coreceptor binding site (13, 21, 51, 54). Finally, the MAbs 2F5, 4E10, and Z13e1 recognize distinct linear sequences in the gp41 membrane-proximal external region (MPER) (36, 57). The targets of these neutralizing MAbs provide a rational starting point for examining the complex nature of polyclonal plasma samples.Several groups have addressed the need to develop methodologies to elucidate the presence of certain neutralizing-antibody specificities (1, 8, 9, 29, 30, 43, 55). A number of these studies reported that the BCN antibodies in plasma can in some cases be adsorbed using gp120 immobilized on beads (1, 9, 29, 30, 43). Furthermore, the activities of some of these anti-gp120 neutralizing antibodies could be mapped to the CD4bs, as the D368R mutant gp120 failed to adsorb them (1, 29, 30, 43).Antibodies to CD4i epitopes are frequently found in HIV-1-infected individuals and are thought to primarily target the coreceptor binding site, which includes the bridging sheet and possibly parts of the V3 region. Decker and colleagues (8) showed that MAbs to HIV-1 CD4i epitopes can neutralize HIV-2 when pretreated with soluble CD4 (sCD4), indicating that the CD4i epitope is highly conserved among different HIV lineages. The poor accessibility of CD4i epitopes, however, has precluded this site from being a major neutralizing-antibody target (24), although a recent study suggested that some of the cross-neutralizing activity in polyclonal sera mapped to a CD4i epitope (30).Another site that has attracted considerable attention as a target for cross-neutralizing antibodies is the MPER, a linear stretch of 34 amino acids in gp41. Anti-MPER antibodies have been detected in the plasma of HIV-infected individuals by using chimeric viruses with HIV-1 MPER grafted into a simian immunodeficiency virus or an HIV-2 envelope glycoprotein (15, 55). These studies concluded that 2F5- and 4E10-like antibodies were rarely found in HIV-1-infected plasmas; however, other specificities within the MPER were recognized by around one-third of HIV-1-infected individuals (15). More recently, 4E10-like and 2F5-like antibodies (30, 43), as well as antibodies to novel epitopes within the MPER (1), have been shown to be responsible for neutralization breadth in a small number of plasma samples. The anti-MPER MAb 4E10 has been shown to react to autoantigens, leading to the suggestion that their rarity in human infection is due to the selective deletion of B cells with these specificities (17, 35). Furthermore, a recent study found an association between anti-MPER and anti-cardiolipin (CL) antibodies, although an association with neutralization was not examined (31).A recent study by Binley and coworkers used an array of methodologies to determine the antibody specificities present in subtype B and subtype C plasma samples with neutralization breadth (1). While antibodies to gp120, some of which mapped to the CD4bs, and to MPER were identified, most of the neutralizing activity in the BCN plasma could not be attributed to any of the known conserved envelope epitopes. Furthermore, it is not clear how common these specificities are among HIV-1-positive plasmas and whether they are only associated with BCN activity.In this study, we investigated a large collection of HIV-1-infected plasmas obtained from the South African National Blood Services. We aimed to determine if there is a relationship between the presence of certain antibody specificities, such as those against CD4i epitopes, MPER, or the CD4bs, and the neutralizing activities present in these plasmas. Furthermore, we evaluated the presence of various autoreactive antibodies and analyzed whether they might be associated with neutralization breadth.     

Simplified methods for monitoring petroleum‐contaminated ground water and soil vapor

Portable meters and simplified gas Chromatographic (GC) techniques were investigated for monitoring volatile hydrocarbon (HC), CO₂, and O₂, concentrations in groundwater, exhaust gases, and soil vapor during in situ remediation using soil vapor extraction (SVE) and air sparging (AS). Results of groundwater samples analyzed in‐house using a headspace technique compared well to split samples analyzed by a certified analytical laboratory (r² = 0.94). SVE exhaust gas HC and CO₂ concentrations measured using a GT201 portable HC/O₂ meter and a RA‐411A meter (GasTech), respectively, were highly correlated with in‐house laboratory GC analyses (r² = 0.91). O₂ concentrations fell in a small range and meter analyses were not well correlated with laboratory analyses. Results of soil gas monitoring were not as well correlated as those for exhaust gases for HC, CO₂, or O₂, perhaps due to environmental conditions such as changes in relative humidity or the wider range of soil gas values. Overall, the meters were good indicators of vapor contamination, they greatly simplified estimates of total HC mass removal, and they allowed estimates of the biological contribution to contaminant removal during the remediation process.     

Characterization of immune responses against gastrointestinal nematodes in weaned lambs grazing willow fodder blocks

A 131-day rotational grazing experiment was conducted in the summer autumn of 2007/2008 to compare effects of feeding condensed tannin (CT)-containing willow (Salix spp.) fodder blocks (i.e., silvopastoral system) or perennial ryegrass (Lolium perenne)/white clover (Trifolium repens) control pasture upon the immune response to gastrointestinal nematode parasite infection in Romney weaned lambs. Groups of lambs (n = 40) were allocated to either willow fodder blocks or control pasture; half of each group (n = 20) were regularly-drenched with anthelmintic at approximately 21 day intervals, whilst the remaining 20 weaned lambs were not drenched unless pre-determined faecal nematode egg counts (FEC) were reached, when all weaned lambs in that group were drenched with anthelmintic (i.e., trigger-drenching). Metabolizable energy and CT concentrations were higher in willow fodder versus pasture herbages. Weaned lambs grazing willow fodder blocks had lower live weight gain (92 g/day) and carcass weight (14.4 kg) than those grazing control pasture (134 g; 15.3 kg), with no effect of anthelmintic drenching. Regular anthelmintic treatment maintained similar and low FEC up to day 82, which then increased, whilst trigger-drenched lambs grazing willow fodder blocks had higher FEC than lambs grazing control pasture on three out of eight occasions. As judged by faecal larval cultures, grazing willow fodder blocks reduced the relative proportions of abomasal-dwelling parasites (Haemonchus contortus and Teladorsagia spp.). Trigger-drenched willow fodder block-fed sheep had higher platelet, eosinophil, total white blood cell and lymphocyte counts, greater CD21⁺ and greater γδ (Gamma Delta) TCR⁺ (T cell receptor) lymphocyte subsets than control pasture-fed sheep, and higher plasma levels of Immunoglobulin A (IgA) specific for carbohydrate larval antigen (CarLa) on day 105 (P<0.001). None of these parameters were affected by grazing treatment in regularly-drenched lambs. Higher immunological measurements in trigger-drenched lambs grazing willow fodder blocks could be due to higher larval intake and/or to the effects of secondary compounds in willow fodder blocks priming the immune system. Further research is required to separate these effects.