Influence of Modifications to the Pechini Method on the Electroactivity and Stability of Pt-RuOx/C Catalysts

Since electrode electroactivity and stability depend directly on the nature, morphology, and structure of the material, we have investigated how modifications to the Pechini method during the synthesis of Pt-RuOx/C electrocatalysts affected catalyst activity. The structure and stability of the resulting materials were investigated after their submission to a large number of potential scans and to constant potential for a prolonged time period in sulfuric acid 0.5 mol L-1 and methanol 0.1 mol L-1 solution. DMFC tests were accomplished using membrane electrode assemblies (MEAs) prepared by hot-pressing a pretreated Nafion 117 membrane together with the prepared Pt-RuOx anodes and a Pt cathode (from E-TEK), in order to compare the catalytic activity of the materials prepared by different methods. The stability studies demonstrated that the catalyst whose resin/carbon support mixture was agitated in a balls mill before undergoing heat-treatment was more stable than the other prepared catalysts. The catalysts synthesized with the single resin consisting of Pt and Ru and subjected to ultrasound before heat-treatment furnished the highest power density in the single fuel cell. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.011208jes]

Molecular surveillance of the Newcastle disease virus in domestic and wild birds on the North Eastern Coast and Amazon biome of Brazil

Brazil is one of the world's largest countries with a rich diversity of wildlife, including resident and migratory wild birds, which may be natural reservoirs of the Newcastle disease virus (NDV). Because Brazil is a major global exporter of chicken meat, the emergence of such a disease may have a huge negative impact not only on the economy due to trade restrictions and embargoes, but also on the quality of life of the population. Samples were collected from 1,022 asymptomatic domestic and wild birds from the Brazilian coast and the Amazon region using tracheal/cloacal swabs and tested by RT-qPCR. The results showed 7 (0.7%) birds were positive for NDV. The positive samples were then isolated in embryonated chicken eggs and their matrix protein genes were partially sequenced, revealing a low-pathogenicity NDV. This study confirms the maintenance of the velogenic-NDV free status of Brazil.

Changes in plant metabolism induced by dioxygenase inhibitors and their effect on the epiphytic microbial community and fire blight (Erwinia amylovora) control

Fire blight, caused by the gram negative bacterium Erwinia amylovora, is one of the most destructive bacterial diseases of Pomaceous plants. Therefore, the development of reliable methods to control this disease is desperately needed. This research investigated the possibility to interfere, by altering plant metabolism, on the interactions occurring between Erwinia amylovora, the host plant and the epiphytic microbial community in order to obtain a more effective control of fire blight. Prohexadione-calcium and trinexapac-ethyl, two dioxygenase inhibitors, were chosen as a chemical tool to influence plant metabolism. These compounds inhibit the 2-oxoglutarate-dependent dioxygenases and, therefore, they greatly influence plant metabolism. Moreover, dioxygenase inhibitors were found to enhance plant resistance to a wide range of pathogens. In particular, dioxygenase inhibitors application seems a promising method to control fire blight. From cited literature, it is assumed that these compounds increase plant defence mainly by a transient alteration of flavonoids metabolism. We tried to demonstrate, that the reduction of susceptibility to disease could be partially due to an indirect influence on the microbial community established on plant surface. The possibility to influence the interactions occurring in the epiphytic microbial community is particularly interesting, in fact, the relationships among different bacterial populations on plant surface is a key factor for a more effective biological control of plant diseases. Furthermore, we evaluated the possibility to combine the application of dioxygenase inhibitors with biological control in order to develop an integrate strategy for control of fire blight. The first step for this study was the isolation of a pathogenic strain of E. amylovora. In addition, we isolated different epiphytic bacteria, which respond to general requirements for biological control agents. Successively, the effect of dioxygenase inhibitors treatment on microbial community was investigated on different plant organs (stigmas, nectaries and leaves). An increase in epiphytic microbial population was found. Further experiments were performed with aim to explain this effect. In particular, changes in sugar content of nectar were observed. These changes, decreasing the osmotic potential of nectar, might allow a more consistent growth of epiphytic bacteria on blossoms. On leaves were found similar differences as well. As far as the interactions between E. amylovora and host plant, they were deeply investigated by advanced microscopical analysis. The influence of dioxygenase inhibitors and SAR inducers application on the infection process and migration of pathogen inside different plant tissues was studied. These microscopical techniques, combined with the use of gpf-labelled E. amylovora, allowed the development of a bioassay method for resistance inducers efficacy screening. The final part of the work demonstrated that the reduction of disease susceptibility observed in plants treated with prohexadione-calcium is mainly due to the accumulation of a novel phytoalexins: luteoforol. This 3-deoxyflavonoid was proven to have a strong antimicrobial activity.

Effects of low-density lipoprotein receptor-related protein 4 and apolipoprotein E isoforms on bone metabolism in vivo

LRP4, member of the LDLR family, is a multifunctional membrane-bound receptor that is expressed in various tissues. The expression of LRP4 by osteoblasts, its novel interaction with Wnt-signaling inhibitors Dkk1 and SOST, and the lower levels of activated beta-catenin in different bone locations described here, adds another player to the long list of established factors that modulate canonical Wnt-signaling in bone. By demonstrating that in addition to Wise, LRP4 is able to interact with two additional important modulators of Wnt- and BMP-signaling, our perspective of the complexity of the integration of BMP and Wnt-signaling pathways on the osteoblast surface has expanded further. Nevertheless the recently described association of both the SOST and LRP4 genes with BMD in humans, together with our findings suggest that LRP4 plays a physiologically important role in the skeletal development and bone metabolism not only in rodents, but in humans as well. The efficiency with which LRP4 binds both SOST and Dkk1, presumably at the osteoblastic surface, LRP4 may act as a sink and competes with LRP5/6 for the binding of these Wnt antagonists, which then are no longer available for suppression of the signal through the LRP5/6 axis. rnApoE, a 299 amino acid glycoprotein, is a crucial regulator in the uptake of triglyceride, phospholipids, cholesteryl esters, and cholesterol into cells. ApoE has been linked to osteoporosis, and such a role is further strengthened by the present of a high bone mass phenotype in ApoE null mice. Until recently, the effects of respective ApoE isoforms E2, E3, and E4, and their impact on bone metabolism, have been unclear. Here we report that respective human ApoE knockin mice display diverse effects on bone metabolism. ApoE2 mice show decreased trabecular bone volume per total volume in femoral bone and lumbar spine in comparison to ApoE3 and E4 animals. In this context, urinary bone resorption marker DPD is increased in these animals, which is accompanied by a low ratio of osteoclastogenesis markers OPG/RANKL. Interestingly, serum bone formation markers ALP and OCN are diminished in ApoE4 mice. In contrast to this finding, ApoE2 mice show the lowest bone formation of all groups in vivo. These findings cannot be explained by the low receptor-affinity of ApoE2 and subsequent decreased uptake of triglyceride-rich lipoproteins by osteoblasts, resulting in elevated levels of undercarboxylated osteocalcin. Thus, other crucial pathways relevant for bone metabolism, e. g. Wnt/beta-catenin-signaling pathways, must be, compared to the ApoE3/4 isoforms, more affected by the ApoE2 isoform.

Thin films of polythiophene: Linear and nonlinear optical characterization

Wir haben die linearen und nichtlinearen optischen Eigenschaften von dünnen Schichten und planaren Wellenleitern aus mehreren konjugierten Polymeren (MEH-PPV und P3AT) und Polymeren mit -Elektronen Systemen in der Seitenkette (PVK und PS) untersucht und verglichen. PVK und PS haben relativ kleine Werte des nichtlinearen Brechungsindex n2 bei 532 nm, nämlich (1,2 ± 0,5)10-14 cm2/W und (2,6 ± 0,5) 10-14 cm2/W.rnWir haben die linearen optischen Konstanten von mehreren P3ATs untersucht, insbesondere den Einfluss der Regioregularität und Kettenlänge der Alkylsubstituenten. Wir haben das am besten geeignete Polymere für Wellenleiter Anwendungen identifiziert, welches P3BT-ra genannt ist. Wir haben die linearen optischen Eigenschaften dünner Schichten des P3BT-ra untersucht, die mit Spincoating aus verschiedenen Lösungsmitteln mit unterschiedlichen Siedetemperaturen präparieret wurden. Wir haben festgestellt, dass P3BT-ra Filme aus Toluol-Lösungen die am besten geeigneten Wellenleiter für die intensitätsabhängigen Prismen-Kopplungs Experimente sind, weil diese geringe Wellenleiterdämpfungsverluste bei = 1064 nm haben. rnWir haben die Dispersionen des Wellenleiterdämfungsverlustes gw, des nichtlinearen Brechungsindex n2 und des nichtlinearen Absorptionskoeffizienten 2 von Wellenleitern aus P3BT-ra im Bereich von 700 - 1500 nm gemessen. Wir haben große Werte des nichtlinearen Brechungsindex bis 1,5x10-13 cm2/W bei 1150 nm beobachtet. Wir haben gefunden, dass die Gütenkriterien (“figures of merit“) für rein optische Schalter im Wellenlängebereich 1050 - 1200 nm erfüllt sind. Dieser Bereich entspricht dem niederenergetischen Ausläufer der Zwei-Photonen-Absorption. Die Gütekriterien von P3BT-ra gehören zu den besten der bisher bekannten Werte von konjugierten Polymeren.rnWir haben gefunden, dass P3BT-ra ein vielversprechender Kandidat für integriert-optische Schalter ist, weil es eine gute Kombination aus großer Nichtlinearität dritter Ordnung, geringen Wellenleiterdämpfungverlusten und ausreichender Photostabilität zeigt. rnWir haben einen Vergleich der gemessenen Dispersion von gw, n2 und 2 mit der Theorie durchgeführt. Durch Kurvenanpassung der Dispersion von gw haben wir gefunden, dass Rayleigh-Streuung der dominierende Dämpfungsmechanismus in MEH-PPV und P3BT-ra Wellenleitern ist. Ein quantenmechanischer Ansatz wurde zur Berechnung der nichtlinearen Suszeptibilität dritter Ordnung (3) verwendet, um die gemessenen Spektren von n2 und 2 von P3BT-ra und MEH-PPV zu simulieren. Dies kann erklären, dass sättigbare Absorption und Zwei-Photonen Absorption die hauptsächlichen Effekte sind, welche die Dispersion von n2 und 2 verursachen. rn

Understanding of stuck fermentations : investigations on the relationship between the microbial diversity and chemical composition of must

Das Ziel dieser Arbeit war es, mehr Informationen über unkonventionelle Gründe für Gärstockungen zu gewinnen und neue Wege zu finden, diese zu überwinden. Mikrobielle Sukzession und die chemische Zusammensetzung bei der Gärung wurden in zwei aufeinander folgenden Jahren in einem Weingut von der oberen Mosel in Deutschland studiert. Es gab keinen Hinweis darauf, dass die isolierten Bakterienspezies oder chemischen Komponenten von Most und Jungwein an schleppenden oder stockenden Gärungen beteiligt waren. Ferner konnte während dieser Arbeit gezeigt werden, dass Saccharomyces bayanus die dominierende Weinhefe in diesem Weingut war statt der klassischen und bekannten Weinhefe Saccharomyces cerevisiae. Während der Gärstockung konnte ein Dreifach-Hybrid Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus wachsen, Saccharomyces bayanus ersetzen und die Gärung beenden. Beide isolierten Hefestämme Saccharomyces bayanus Stamm HL 77 und der Dreifach-Hybrid Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus Stamm HL 78 konnten Glucose und Fructose von Anfang an verwerten und konnten bei niedrigen Temperaturen von 15 °C und in der Abwesenheit von Hefe-verwertbarem Stickstoff in Form von Ammonium wachsen, solange Aminosäuren im Medium vorhanden waren, im Gegensatz zu einer kommerziellen Saccharomyces cerevisiae-Starterkultur. Chemische Untersuchungen ergaben, dass Hefe-verwertbarer Stickstoff in dem kooperierenden Weingut mit einem Maximum von 160 mg/l zu Beginn der Gärung vorhanden war und auf 40 mg/L verringert war nach zwei Wochen. Aus diesem Grund sind beide isolierten Hefestämme interessant als Starterkulturen in diesem Weingut und dies kann neben der niedrigen Temperatur im Keller auch ein Grund sein, warum Saccharomyces cerevisiae nicht die dominierende Weinhefe in diesem Fall ist. Der Dreifach-Hybrid Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus Stamm HL 78 ist in der Lage, Fructose noch effizienter zu nutzen als Saccharomyces bayanus Stamm HL 77 und ist weniger abhängig von der Aminosäurekonzentration. Dieser Stamm wurde bereits erfolgreich bei diesem Projekt eingesetzt, um eine Gärstockung in dem kooperierenden Weingut zu beheben. Es ist bekannt, dass Saccharomyces-Hybride in der Weinherstellung vorkommen aber ihre Rolle bei der Überwindung von Gärstockungen wurde bisher noch nicht beschrieben. Diese Ergebnisse sind nützlich, um Gärstockungen zu vermeiden oder zu überwinden mit der selektiven Verwendung dieser Hefestämme in verschiedenen Stadien der Gärung. Das kooperierende Weingut, welches im oberen Qualitätssegment platziert ist, hatte jedes Jahr Probleme mit Gärstockungen. Daher ist die Anwendung der Dreifach-Hybriden Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus Stamm HL 78 eine große Chance, Gärstockungen und finanzielle Verluste ohne kommerzielle Starterkulturen oder andere übliche Praktiken, die zu einer Veränderung des Aromaprofils führen können, zu vermeiden. Die beschriebenen Untersuchungen stellen ein Modell dar, um Gärstockungen auch in anderen Weingütern, die Spontangärungen anwenden, zu überwinden.

On the traces of XPD: cell cycle matters - untangling the genotype-phenotype relationship of XPD mutations

Abstract Mutations in the human gene coding for XPD lead to segmental progeria - the premature appearance of some of the phenotypes normally associated with aging - which may or may not be accompanied by increased cancer incidence. XPD is required for at least three different critical cellular functions: in addition to participating in the process of nucleotide excision repair (NER), which removes bulky DNA lesions, XPD also regulates transcription as part of the general transcription factor IIH (TFIIH) and controls cell cycle progression through its interaction with CAK, a pivotal activator of cyclin dependent kinases (CDKs). The study of inherited XPD disorders offers the opportunity to gain insights into the coordination of important cellular events and may shed light on the mechanisms that regulate the delicate equilibrium between cell proliferation and functional senescence, which is notably altered during physiological aging and in cancer. The phenotypic manifestations in the different XPD disorders are the sum of disturbances in the vital processes carried out by TFIIH and CAK. In addition, further TFIIH- and CAK-independent cellular activities of XPD may also play a role. This, added to the complex feedback networks that are in place to guarantee the coordination between cell cycle, DNA repair and transcription, complicates the interpretation of clinical observations. While results obtained from patient cell isolates as well as from murine models have been elementary in revealing such complexity, the Drosophila embryo has proven useful to analyze the role of XPD as a cell cycle regulator independently from its other cellular functions. Together with data from the biochemical and structural analysis of XPD and of the TFIIH complex these results combine into a new picture of the XPD activities that provides ground for a better understanding of the patophysiology of XPD diseases and for future development of diagnostic and therapeutic tools.

Influence of diurnal hyperosmotic loading on the metabolism and matrix gene expression of a whole-organ intervertebral disc model

It is generally agreed that the mechanical environment of intervertebral disc cells plays an important role in maintaining a balanced matrix metabolism. The precise mechanism by which the signals are transduced into the cells is poorly understood. Osmotic changes in the extracellular matrix (ECM) are thought to be involved. Current in-vitro studies on this topic are mostly short-term and show conflicting data on the reaction of disc cells subjected to osmotic changes which is partially due to the heterogenous and often substantially-reduced culture systems. The aim of the study was therefore to investigate the effects of cyclic osmotic loading for 4 weeks on metabolism and matrix gene expression in a full-organ intervertebral disc culture system. Intervertebral disc/endplate units were isolated from New Zealand White Rabbits and cultured either in iso-osmotic media (335 mosmol/kg) or were diurnally exposed for 8 hours to hyper-osmotic conditions (485 mosmol/kg). Cell viability, metabolic activity, matrix composition and matrix gene expression profile (collagen types I/II and aggrecan) were monitored using Live/Dead cell viability assay, tetrazolium reduction test (WST 8), proteoglycan and DNA quantification assays and quantitative PCR. The results show that diurnal osmotic stimulation did not have significant effects on proteoglycan content, cellularity and disc cell viability after 28 days in culture. However, hyperosmolarity caused increased cell death in the early culture phase and counteracted up-regulation of type I collagen gene expression in nucleus and annulus cells. Moreover, the initially decreased cellular dehydrogenase activity recovered with osmotic stimulation after 4 weeks and aggrecan gene down-regulation was delayed, although the latter was not significant according to our statistical criteria. In contrast, collagen type II did not respond to the osmotic changes and was down-regulated in both groups. In conclusion, diurnal hyper-osmotic stimulation of a whole-organ disc/endplate culture partially inhibits a matrix gene expression profile as encountered in degenerative disc disease and counteracts cellular metabolic hypo-activity.

On the Accelerated Failure Time Model for Current Status and Interval Censored Data

This paper introduces a novel approach to making inference about the regression parameters in the accelerated failure time (AFT) model for current status and interval censored data. The estimator is constructed by inverting a Wald type test for testing a null proportional hazards model. A numerically efficient Markov chain Monte Carlo (MCMC) based resampling method is proposed to simultaneously obtain the point estimator and a consistent estimator of its variance-covariance matrix. We illustrate our approach with interval censored data sets from two clinical studies. Extensive numerical studies are conducted to evaluate the finite sample performance of the new estimators.

Impact of preservation solution on the extent of blood-air barrier damage and edema formation in experimental lung transplantation

A major aim in lung transplantation is to prevent the loss of structural integrity due to ischemia and reperfusion (I/R) injury. Preservation solutions protect the lung against I/R injury to a variable extent. We compared the influence of two extracellular-type preservation solutions (Perfadex, or PX, and Celsior, or CE) on the morphological alterations induced by I/R. Pigs were randomly assigned to sham (n = 4), PX (n = 5), or CE (n = 2) group. After flush perfusion with PX or CE, donor lungs were excised and stored for 27 hr at 4 degrees C. The left donor lung was implanted into the recipient, reperfused for 6 hr, and, afterward, prepared for light and electron microscopy. Intra-alveolar, septal, and peribronchovascular edema as well as the integrity of the blood-air barrier were determined stereologically. Intra-alveolar edema was more pronounced in CE (219.80 +/- 207.55 ml) than in PX (31.46 +/- 15.75 ml). Peribronchovascular (sham: 13.20 +/- 4.99 ml; PX: 15.57 +/- 5.53 ml; CE: 31.56 +/- 5.78 ml) and septal edema (thickness of alveolar septal interstitium, sham: 98 +/- 33 nm; PX: 84 +/- 8 nm; CE: 249 +/- 85 nm) were only found in CE. The blood-air barrier was similarly well preserved in sham and PX but showed larger areas of swollen and fragmented epithelium or endothelium in CE. The present study shows that Perfadex effectively prevents intra-alveolar, septal, and peribronchovascular edema formation as well as injury of the blood-air barrier during I/R. Celsior was not effective in preserving the lung from morphological I/R injury.

Life-patterns on the periphery : a humanities base for development imperatives and their application in the Chicago city-region

Life-Patterns on the Periphery: A Humanities Base for Development Imperatives and their Application in the Chicago City-Region is informed by the need to bring diverse fields together in order to tackle issues related to the contemporary city-region. By honouring the long-term economic, social, political, and ecological imperatives that form the fabric of healthy, productive, sustainable communities, it becomes possible to setup political structures and citizen will to develop distinct places that result in the overlapping of citizen life patterns, setting the stage for citizen action and interaction. Based in humanities scholarship, the four imperatives act as checks on each other so that no one imperative is solely honoured in development. Informed by Heidegger, Arendt, deCerteau, Casey, and others, their foundation in the humanities underlines their importance, while at the same time creating a stage where all fields can contribute to actualizing this balance in practice. For this project, theoretical assistance has been greatly borrowed from architecture, planning theory, urban theory, and landscape urbanism, including scholarship from Saskia Sassen, John Friedmann, William Cronon, Jane Jacobs, Joel Garreau, Alan Berger, and many others. This project uses the Chicago city-region as a site, specifically the Interstate 80 and 88 corridors extending west from Chicago. Both transportation corridors are divided into study regions, providing the opportunity to examine a broad variety of population and development densities. Through observational research, a picture of each study region can be extrapolated, analyzed, and understood with respect to the four imperatives. This is put to use in this project by studying region-specific suggestions for future development moves, culminating in some universal steps that can be taken to develop stronger communities and set both the research site specifically and North American city-regions in general on a path towards healthy, productive, sustainable development.

A Study on the Origin of Banded Agate

Agate in any of its varieties presents numerous problems in regard to its origin. Many types have been described and their beauty elaborated upon, but little has been written concerning their formation and the problems involved. The genesis of agate implicates an amazing complexity of physical and colloid­al chemistry, as well as, various principles of geology.

Values of children and family models of adolescents: An eleven-culture study

Starting from Kagitcibasi's (2007) conceptualization of family models, this study compared N = 2961 adolescents' values across eleven cultures and explored whether patterns of values were related to the three proposed family models through cluster analyses. Three clusters with value profiles corresponding to the family models of interdependence, emotional interdependence, and independence were identified on the cultural as well as on the individual level. Furthermore, individual-level clusters corresponded to culture-level clusters in terms of individual cluster membership. The results largely support Kagitcibasi's proposition of changing family models and demonstrate their representation as individual-level value profiles across cultures.

A survey on the feeding of eventing horses during competition

This study aims at the comparison of the actual feeding of horses with the recommendations from the literature, and it studies the effects of feeding and exercise on several blood metabolic parameters before and after exercise. Blood samples were collected from 25 horses during one-star eventing competitions and evaluated for blood glucose, insulin, lactate, free fatty acids and triglyceride levels. Questionnaires on the feeding practices of the horses were evaluated. The questionnaires revealed that during training, and on tournament days, horses received on average 4.3 kg of concentrate per day (min. 1.54 kg, max. 8 kg). The statistical analysis showed no significant effect of the amount of concentrate fed before exercise on the measured blood values. Oil was supplied as a supplementary energy source to 30% of the horses, but most of them only received very small quantities (0.02–0.4 l/day). Five horses (20%) had no access to salt supplements at all, and eleven horses (45%) had no access to salt on tournament days. Fifteen horses (60%) were supplied with mineral feed. Twenty-one horses (84%) had daily access to pasture during the training period. During competition, 55% of the horses received roughage ad libitum, compared with 37% during training. The majority of the horses received less roughage on days before the cross-country competition. It could not be ascertained whether feeding a large amounts of roughage had a beneficial effect on performance, because only a few horses in this study were fed with very restrictive roughage. Feeding of most of the horses was in agreement with the recommendations from the literature, except the need for sodium and chloride. The sodium and chloride need for sport horses may be overestimated in literature and needs to be re-evaluated.

The emergence of the social determinants of health on the policy agenda in Britain: A case study, 1980--2003

Numerous theories have been advanced in the effort to explain how a given policy issue manages to take root in the public sphere and subsequently move forward on the public legislative agenda—or not. This study examined how the social determinants of health (SDOH) came to be part of the legislative policy agenda in Britain from 1980 to 2003. ^ The specific objectives of the research were: (1) to conduct a sociopolitical analysis grounded in alternative agenda-setting theories to identify the factors responsible for moving the social determinants health perspective onto the British policy agenda; and (2) to determine which of the theories and related dimensions best accounted for the emergence of this perspective. ^ A triangulated content and context analysis of British news articles, historical accounts, and research commentaries of the SDOH movement was conducted guided by relevant agenda-setting theories set within a social movement framework to chronicle the emergence of the SDOH as a significant policy issue in Britain. ^ The most influential social movement and agenda setting elements in the emergence of the SDOH in Britain were issue generation tactics, framing efforts, mobilizing structures, and political opportunities grounded in social movement and agenda setting theories. Policy content or the details of the policy had comparatively little impact on the successful emergence of the SDOH. Despite resistance by the government, from 1980 to 1996 interest groups created a political understanding of the SDOH utilizing a framing package encompassing notions of inequality, fairness, and justice. This frame transmitted a powerful idea connected to a core set of British values and beliefs. After 1996, a shift in political opportunities cemented the institutional arrangements needed to sustain an environment conducive to the development and implementation of SDOH policies and programs. ^ This research demonstrates that the U.S. emergence of the SDOH on the policy agenda will depend upon: (1) U.S. ideals and values regarding poverty, inequality, race, health, and health care that will determine issue framing; (2) political opportunities that will emerge—or not—to advance the SDOH policy agenda; and (3) the mobilizing structures that support or oppose the issue. ^