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The study seeks to confront the challenge of incorporating the role of inequality, identity, and intersectionality into political science teaching and learning. In this quasi-experimental design, we explore the variation in two introductory courses in public policy. The design and content were similar for both sections. For the experimental section, we integrated intersectional political science pedagogy. This section employed a flipped classroom, introducing innovative approaches to grading and assessment that were accessible, inclusive, and anti-racist. In the control group section, the course was traditionally taught without supplemental material on intersectionality or the more innovative and unconventional pedagogy. We hypothesize that students enrolled in the intersectional section will have more interest and knowledge in public policy, as well as a deeper understanding of racial progress as it relates to the policy process. Moreover, we predict that students will display some resistance and discomfort when it comes to participating in class discussions.

We evaluated the performance of self-collected anterior nasal swab (ANS) and saliva samples compared with healthcare worker-collected nasopharyngeal swab specimens used to test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We used the same PCR diagnostic panel to test all self-collected and healthcare worker-collected samples from participants at a public hospital in Atlanta, Georgia, USA. Among 1,076 participants, 51.9% were men, 57.1% were >50 years of age, 81.2% were Black (non-Hispanic), and 74.9% reported >1 chronic medical condition. In total, 8.0% tested positive for SARS-CoV-2. Compared with nasopharyngeal swab samples, ANS samples had a sensitivity of 59% and saliva samples a sensitivity of 68%. Among participants tested 3-7 days after symptom onset, ANS samples had a sensitivity of 80% and saliva samples a sensitivity of 85%. Sensitivity varied by specimen type and patient characteristics. These findings can help physicians interpret PCR results for SARS-CoV-2.

Stable catalysts are essential to address energy and environmental challenges, especially in harsh environment applications (high temperature, oxidizing atmosphere, steam). In such conditions, supported metal catalysts deactivate due to sintering – a process where initially small nanoparticles grow into larger ones with reduced active surface area. Strategies to stabilize them lead to decreased performance. Here, we report stable catalysts prepared through the encapsulation of platinum particles inside an alumina framework. These catalysts do not sinter at 800 °C in the presence of oxygen and steam, conditions in which conventional catalysts sinter to large extents, while showing similar reaction rates. Extending this approach to Pd/Pt bimetallic catalysts leads to maintained small particle size at temperatures as high as 1,100 °C in air and steam. This strategy can be broadly applied to other metal and metal oxides for applications where sintering is a major cause of materials deactivation.

Gastroesophageal adenocarcinoma (GEA) is the fastest rising cancer in North America. Over the course of five years, the survival rate is 200 GEA patients. A single-cell RNA sequencing atlas developed from >30 GEA DCF- or FLOT-treated patient samples will be used to identify CAF markers and targetable processes. CAF sub-populations will then be elucidated and correlated to tumor response. IF, FACS, and ELISA will be performed for subsequent CAF marker validation and characterization. Ex vivo drug testing with DCF or FLOT will be conducted on PDO-CAF co-cultures to recapitulate their drug response. Citation Format: Kulsum Tai, Sanjima Pal, Julie Bérubé, Iris Kong, Adam Hoffman, Swneke Bailey, Aki Kirbizakis, Sui Huang, Michael Strasser, David Gibbs, Nicholas Bertos, Veena Sangwan, Lorenzo Ferri. Dissecting the stromal drivers of gastroesophageal adenocarcinoma chemoresistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5959.

We aimed to describe frequency of COVID-19 exposure risk factors among patients presenting for medical care at an urban, public hospital serving mostly uninsured/Medicare/Medicaid clients and risk factors associated with SARS-CoV-2 infection. Consenting, adult patients seeking care at a public hospital from August to November 2020 were enrolled in this cross-sectional investigation. Saliva, anterior nasal and nasopharyngeal swabs were collected and tested for SARS-CoV-2 using RT-PCR. Participant demographics, close contact, and activities ≤14 days prior to enrollment were collected through interview. Logistic regression was used to identify risk factors associated with testing positive for SARS-CoV-2. Among 1,078 participants, 51.8% were male, 57.0% were aged ≥50 years, 81.3% were non-Hispanic Black, and 7.6% had positive SARS-CoV-2 tests. Only 2.7% reported COVID-19 close contact ≤14 days before enrollment; this group had 6.79 adjusted odds of testing positive (95%CI = 2.78–16.62) than those without a reported exposure. Among participants who did not report COVID-19 close contact, working in proximity to ≥10 people (adjusted OR = 2.17; 95%CI = 1.03–4.55), choir practice (adjusted OR = 11.85; 95%CI = 1.44–97.91), traveling on a plane (adjusted OR = 5.78; 95%CI = 1.70–19.68), and not participating in an essential indoor activity (i.e., grocery shopping, public transit use, or visiting a healthcare facility; adjusted OR = 2.15; 95%CI = 1.07–4.30) were associated with increased odds of testing positive. Among this population of mostly Black, non-Hispanic participants seeking care at a public hospital, we found several activities associated with testing positive for SARS-CoV-2 infection in addition to close contact with a case. Understanding high-risk activities for SARS-CoV-2 infection among different communities is important for issuing awareness and prevention strategies.

Introduction The Throckmorton sign, or John Thomas sign, is a well-established orthopedic eponym, anecdotally used in orthopedic surgery to correlate the direction of male genitalia, observed on a pelvic radiograph, with the laterality of an associated orthopedic pathology. In earlier studies, the direction of pelvic shadowing on X-ray has been neither a credible nor a reliable predictor of fracture laterality. Given this small body of evidence, we sought to further investigate the relationship between peri-trochanteric hip fracture laterality and male genitalia lie. Method A single-center retrospective chart review was conducted of 397 consecutive male patients who received pelvic radiographs performed upon entry to an urban level 1 trauma center. Exclusion criteria included age less than 18 years or a prior history of pelvic or urological surgery. Of this cohort, 360 patients met the inclusion criteria and underwent investigation. Results The study population had an average age of 42 years (range: 18-91 years). Statistical analysis yielded a 4.24 relative risk with pelvic shadowing laterality and respective peri-trochanteric hip fracture sidedness. Additionally, there was a 4.63 and 9.88 relative risk of tibial shaft fractures and distal radius fractures having a concomitant positive Throckmorton Sign, respectively. Conclusion Pelvic shadowing can be used as an additional diagnostic tool in predicting peri-trochanteric hip fracture sidedness in a trauma bay setting.

The Trump administration has altered perceptions of United States politics in many ways, in particular in understandings of the role and importance of campaigns, elections, parties, and voting beha...

Introduction Home-based care (HBC) is a valuable tool to provide care to rural, medically underserved populations. By mitigating geographic and transportation barriers for vulnerable populations, HBC is a promising modality of health care delivery. Interprofessional education has become an integral part in undergraduate and professional curricula; however, applications of team-based training in HBC are often missing from curricula. When included, instruction in HBC often utilizes didactic instruction or laboratory experiences, which are discipline-specific and lack a focus on integration of team-based care. Methods We implemented a standardized patient (SP) simulation of a posthospital discharge home visit using a team of learners from nursing, physical therapy (PT), occupational therapy (OT), dentistry, pharmacy, and medicine in a simulated home environment. Pre- and postsimulation competencies of interprofessional care were measured using the 20-item Interprofessional Collaborative Competency Attainment Survey (ICCAS). Results Throughout the academic years of August 2018 – August 2020, 68 students from nursing, PT, OT, pharmacy, medicine, and dentistry completed a simulated home visit with an SP discharged from a hospital. For all 20 perceived abilities on the ICCAS, learners showed a statistically significant increase in postsurvey measurement. A modest to large (.31 ≤ r ≤ .94) effect size was observed in the majority of responses. Discussion This SP simulation described a novel, interdisciplinary approach to incorporating HBC into interprofessional curricula.

Introduction: Esophagogastric adenocarcinomas with microsatellite instability (MSI) high status often display chemoresistance, as the current therapies are ineffective. It is hypothesized that the poor response of MSI-high esophagogastric adenocarcinomas to therapies is due to the extensive genomic mutational heterogeneity, which can be overcome by identifying, stratifying, and targeting multiple genetic alterations concurrently. The goals of this project are to: 1) Identify a matched retrospective cohort of 20 MSI-high to 20 microsatellite stable organoids, derived from biobanked tumor tissue. 2) Analyze mismatch repair protein function/loss, to confirm that the primary tumor microsatellite status is recapitulated in 3D organoid models. 3) Test standard of care chemotherapies, and explore alternative approaches to prevent chemoresistance by evaluating targeted agents based on genomic sequencing. Methods: Patient-derived organoids grow for ~14 days, after which they are enzymatically disrupted and plated in Matrigel. I will confirm that the organoid models accurately represent clinal response, by treating them with the same chemotherapy received by the patient. 10 different drug concentrations are added in triplicate using a drug dispenser, then after 72 hours, organoid viability is determined with a plate reader. Results: Genomic characterization of 13/226 MSI-high cases has been conducted with a 234 gene gastric cancer specific panel to identify and target genomic alterations. Preliminary robotic drug screens guided by these mutation profiles have been conducted, yielding promising alternative treatments. Conclusions: By targeting the particular mutations found in MSI-high patients, it could help explain the chemoresistance mechanism, so promising personalized treatment approaches for esophagogastric adenocarcinomas can be clinically implemented. Sources of Funding: This project is funded by the Inez and Willena Beaton Award in Oncology, valued at $7,500 and provided by the RI-MUHC. The operating grants that support the research are $120,000 over 2 years from the Cancer Research Society, and $1,200,000 USD over 3 years given by the Department of Defense. Citation Format: Adam Hoffman, Sanjima Pal, Veena Sangwan, Lorenzo Ferri. Personalized chemotherapy treatments for microsatellite instable tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2625.

Nasopharyngeal swabs (NPS) collected by trained healthcare professionals are the preferred specimen for SARS-CoV-2 testing. Self-collected specimens might decrease patient discomfort, conserve healthcare resources, and be preferred by patients. During August – November 2020, 1,806 adults undergoing SARS-CoV-2 testing in Denver, Colorado and Atlanta, Georgia, provided self-collected anterior nares swabs (ANS) and saliva specimens before NPS collection. Compared to NPS, sensitivity for SARS-CoV-2 detection by rRT-PCR appeared higher for saliva than for ANS (85% versus 80% in Denver; 67% versus 58% in Atlanta) and higher among participants reporting current symptoms (94% and 87% in Denver; 72% and 62% in Atlanta, for saliva and ANS, respectively) than among those reporting no symptoms (29% and 50% in Denver; 50% and 44% in Atlanta, for saliva and ANS, respectively). Compared to ANS, saliva was more challenging to collect and process. Self-collected saliva and ANS are less sensitive than NPS for SARS-CoV-2 detection; however, they offer practical advantages and might be most useful for currently symptomatic patients.

Self-collected specimens can expand access to SARS-CoV-2 testing. At a large inner-city hospital 1,082 participants self-collected saliva and anterior nasal swab (ANS) samples before healthcare workers collected nasopharyngeal swab (NPS) samples on the same day. To characterize patient preferences for self-collection, this investigation explored ability, comfort, and ease of ANS and saliva self-collection for SARS-CoV-2 testing along with associated patient characteristics, including medical history and symptoms of COVID-19. With nearly all participants successfully submitting a specimen, favorable ratings from most participants (at least >79% in ease and comfort), and equivocal preference between saliva and ANS, self-collection is a viable SARS-CoV-2 testing option.

Understanding the organizational framework and predictive powers of the periodic table is paramount in preparing students for success in chemistry. An interactive classroom activity was developed to engage students as they analyzed and evaluated the repeating trends in physical and chemical properties of elements displayed on the periodic table. This activity transforms the class into a “representative” periodic table, with each student portraying a unique element as they analyze their relation to their elemental neighbors, evaluate statements regarding their periodic peers, and explore of the power of periodicity present within the periodic table. Prior to this activity, the students correctly answered just over 10% of the questions asking them to evaluate periodic trends, while after the activity the students correctly answered over 50% of the questions covering the same content. Student feedback was positive and highlighted the interactive and engaging qualities of the activity. The People Periodic Tab...

Earth's critical zone (CZ) is the uppermost layer of Earth's continents, which supports ecosystems and humans alike. CZ science aims to understand how interactions among rock, soil, water, air, and terrestrial organisms influence Earth as a habitable system. Thus, CZ science provides the framework for a holistic-systems approach to teaching Earth surface and environmental science, especially related to environmental sustainability. Here, we describe efforts by an interdisciplinary team to create a full-semester, university curriculum that introduces upper-division students to CZ science. Course topics include a background in CZ science, key concepts and methods of CZ science, and units on land–atmosphere interactions, water budgets, landscape evolution, and biogeochemistry. The course culminates with a unit on human interactions within the CZ. Through interactive activities that use data sets from U.S. CZ observatories, the course emphasizes how a CZ framework is appropriate for teaching concepts...

In this study, I look at 15 introductory American government textbooks to assess the degree to which they move beyond traditional models of pluralism and toward a more critical approach of one that reflects recent scholarship. I find that the great majority of texts, perhaps fearing that a more critical approach would lead to political and civic disengagement by undergraduates, present an overly idealized version of American government and politics.

Author(s): Gay, David; Steratore, Anthony; Hoffman, Adam; Neidhardt, Jessica; Cundiff, Courtney; Shaver, Erica; Kiefer, Autumn; Kiefer, Christopher

Runoff of nutrients and erosion of soil from agricultural lands affect soil fertility and are important nonpoint contributors of P and N to surface and ground waters, yet studies of edge-of-field nutrient transport from snowmelt or rainfall runoff on frozen ground are limited. The objective of this study was to quantify the temporal and spatial variation in edge-of-field snowmelt, rain, and mixed (rain on snow) runoff events for sediment and P loadings in five agricultural subwatersheds over a 12-yr period. Edge-of-field runoff events from five subwatersheds at Pioneer Farm near Platteville, WI, ranging in size from approximately 4 to 30 ha were sampled using automated samplers from 2002 through 2014 to determine sediment and P yields (mass loads). Mean dissolved reactive P (DRP) runoff concentrations for each event type (rain = 1.24 mg L, snow = 1.90 mg L, mix = 2.23 mg L) were above total P (TP) water quality guidelines for surface waters. The percentages of TP that was DRP for snow, mixed, and rain events were 74, 84, and 39%, respectively. Although variation in total annual P yield in edge-of-field runoff was noted between years and among sites within a given year, when aggregated over the study period, the subwatersheds showed similar transport characteristics with respect to DRP and TP yield. This study highlights the importance of examining long-term datasets in quantifying annual yields and understanding the timing of DRP and TP transport for developing best management practices and improving model accuracy in cold weather agricultural systems.

In this paper, we compare the accuracy of four bifacial irradiance models used in the photovoltaic industry, by benchmarking them against field measurements. Using the bifacial irradiance modeling tools bifacial_radiance (ray tracing), bifacialvf, pvfactors and PVSyst, we modeled the front- and backside irradiance at two test sites: a fixed-tilt PV system installed in Albuquerque, NM and a single-axis tracker PV system installed in Davis, CA. We found that all four models predicted annual energy impact of bifacial gain within ±1% of one another, and the fast view-factors-based models matched the accuracy of the more computationally intensive ray tracing model. We also investigated the impact of albedo and found bifacial gain values of about 4% for the 0.16 albedo condition and about 9% for the 0.56 albedo condition for the single-axis tracking system. Our model validation work shows that pvfactors is an accurate and highly customizable solution for evaluating the front and backside irradiance in bifacial PV systems.

Author(s): Steratore, Anthony; Shaver, Erica; Sharon, Melinda; Hoffman, Adam; Martin, Peter; Kiefer, Christopher

The Interdisciplinary Teaching about Earth Science for a Sustainable Future (InTeGrate) course “Critical Zone Science” (CZS) teaches undergraduate students about the services and resources provided by the critical zone (CZ), Earth’s terrestrial layer that extends from the top of vegetation to unweathered bedrock. The course was developed through the InTeGrate program, which aims to improve undergraduate geosciences education by teaching earth science within the context of societal grand challenges. CZ science provides a valuable transdisciplinary framework through which students learn the nature and methods of geosciences and apply systems thinking as they investigate grand challenges facing society. Using a CZ approach to learn about Earth systems and the services provided by the CZ has the potential to deeply engage students and develop skills necessary to consider how we can achieve environmental sustainability. While teaching the CZS course, instructors employ active learning pedagogical practices using authentic data and current research from the National Science Foundation CZ Observatory program. The CZS course was piloted across a range of institutions and most recently at the University of Nebraska Omaha (UNO), a large, 4-year public and primarily nonresidential campus. Here we present a case study of implementing the course into UNO’s undergraduate curriculum, including strategies and challenges of delivering the course, and describe additional attempts to assess course outcomes, including a new summative assessment tool. Assessment data from pilot courses and the most recent UNO course offering show that students leave the course with a high interest level in earth science and sustainability and the ability to apply complex thinking skills, but additional assessment tools are needed to more effectively assess the ways in which these materials impact student learning and critical thinking skills.

In this quasi-experimental design, I examine the impact of a political engagement program on students, looking at traditional measures of internal efficacy, as well as other areas of political engagement including levels of political knowledge, the development of political skills, and interest in media coverage of politics.

A multipart laboratory activity introducing microbeads was created to meet engineering and engineering design practices consistent with new Next Generation Science Standards (NGSS). Microbeads are a current topic of concern as they have been found to cause adverse impacts in both marine and freshwater systems resulting in multiple states proposing or adopting legislation to ban their manufacture or sale. The activity allows for student inquiry, discovery, and engineering design using inexpensive, readily available, and safe chemicals. In addition, the products tested (toothpastes, facial-cleansers, and/or hand-cleansers) will be familiar items to the students, stressing the ubiquitous nature of chemistry. The activity fostered confidence in the students through designing and testing procedures, introduced them to a topic that most knew nothing about, and drew praise for achieving the learning goals while investigating a relevant real-world problem.

The authors propose a working definition of ethical Scholarship of Teaching and Learning (SoTL), advance an ethical framework for SoTL inquiry, and present a case study that illustrates the complexity of ethical issues in SoTL. The Ethical SoTL Matrix is a flexible framework designed to support SoTL practitioners, particularly in the formative stages of their inquiries. Three dominant ethical traditions form the basis of the matrix: teleological or pragmatic, external, and deontological. The key message of the paper is that SoTL practitioners should reflect on different perspectives in their efforts to do what is right in any given situation. The matrix introduces three dominant ethical traditions, but SoTL practitioners may ultimately move beyond these traditions to explore a range of ethical considerations appropriate to their projects and disciplines.

Internal regulatory controls of phosphorus (P) via iron (Fe) scavenging were quantified in four contrasting dimictic Wisconsin lakes: Mendota (eutrophic, calcareous), Fish (mesotrophic, calcareous), Devil’s (mesotrophic, noncalcareous), and Sparkling (oligotrophic, noncalcareous). Hypolimnetic enrichment of P was highest in Mendota and Devil’s and least in Fish and Sparkling. This enrichment was attributed mainly to internal loading in the noncalcareous lakes and regeneration of sedimenting epilimnetic P in the calcareous lakes. Differences in Fe scavenging efficiencies at fall turnover were related to hypolimnetic Fe:P molar ratios as well as Fe availability and its control by sulfate–sulfide chemistries. In the noncalcareous lakes with high hypolimnetic Fe enrichment (Fe:P > 2), 45% of whole-lake total P was removed. P removal was low (

Endophytic bacteria have been shown to provide several advantages to their host, including enhanced growth. Inoculating biofuel species with endophytic bacteria is therefore an attractive option to increase the productivity of biofuel feedstocks. Here, we investigated the effect of inoculating hard wood cuttings of Populus deltoides Bartr. x Populus. nigra L. clone OP367 with Enterobacter sp. 638. After 17 weeks, plants inoculated with Enterobacter sp. 638 had 55% greater total biomass than un-inoculated control plants. Study of gas exchange and fluorescence in developing and mature leaves over a diurnal cycle and over a 5 week measurement campaign revealed no effects of inoculation on photosynthesis, stomatal conductance, photosynthetic water use efficiency or the maximum and operating efficiency of photosystem II. However, plants inoculated with Enterobacter sp. 638 had a canopy that was 39% larger than control plants indicating that the enhanced growth was fueled by increased leaf area, not by improved physiology. Leaf nitrogen content was determined at two stages over the 5 week measurement period. No effect of Enterobacter sp. 638 on leaf nitrogen content was found indicating that the larger plants were acquiring sufficient nitrogen. Enterobacter sp. 638 lacks the genes for N{sub 2} fixation, therefore the increased availability more » of nitrogen likely resulted from enhanced nitrogen acquisition by the 84% larger root system. These data show that Enterobacter sp. 638 has the potential to dramatically increase productivity in poplar. If fully realized in the production environment, these results indicate that an increase in the environmental and economic viability of poplar as a biofuel feedstock is possible when inoculated with endophytic bacteria like Enterobacter sp. 638. « less

CASE Traumatic bilateral asymmetric hip dislocation represents an exceedingly rare injury pattern in which one hip dislocates anteriorly and the contralateral hip dislocates posteriorly. Few reports of this injury pattern have been published in the English literature, and no report of this pattern with arterial occlusion has been described. We report a case of asymmetric hip dislocations presenting with a pulseless lower extremity after a motor vehicle accident. No arterial injury was identified on computed tomography angiogram. Fractures of the proximal femur and acetabulum were also absent, bilaterally. CONCLUSIONS We present a patient who patient underwent successful closed reduction with return of pulses in the left leg and required no further intervention for his hip dislocations.

Students explore the fundamental chemical concepts of vapor pressure and flash point in a real-world technical context, while gaining insight into the contemporary societal issue of biofuels. Lab activities were developed using a closed-cup instrument to measure the flash point of various biodiesel samples. Pre- and post-tests revealed that the student’s grasp of the relationship between vapor pressure and flash point went from 46% to 91% after completing the lab and 76% of students responded that measurement of flash point helped them better understand the concept of vapor pressure. In the 3-h lab, students produce a small sample of biodiesel fuel and then evaluate the safety and quality of their product compared with a commercially available reference fuel that meets ASTM specifications. The experiment illustrates how fuel properties depend on the production process and the resulting composition and purity of the fuel product. The observed differences in fuel flash points provide for an introduction of the concepts of chemical quality assurance and quality control. The goal of this lab is to increase understanding of biofuels and associated chemical concepts that influence the properties of various renewable and fossil fuels.

In 2006, we collected flow, sediment, and phosphorus (P) data at stream locations upstream and downstream of a small degraded wetland in south-central Wisconsin traversed by a stream draining a predominantly agricultural watershed. The amount of sediment that left the wetland in the two largest storms, which accounted for 96% of the exported sediment during the observation period, was twice the amount that entered the wetland, even though only 50% of the wetland had been inundated. This apparently anomalous result is due to erosion of sediment that had accumulated in the low-gradient channel and to the role of drainage ditches, which trapped sediment during the wetland-filling phase. In the case of total P, the inflow to the wetland approximately equaled the outflow, although the wetland sequestered 30% of the incoming dissolved reactive P. The discrepancy is almost certainly due to net export of sediment. Many wetlands in the glaciated midwestern United States are ditched and traversed by low-gradient channels draining predominantly agricultural areas, so the processes observed in this wetland are likely to be common in that region. Knowledge of this behavior presents opportunities to improve water quality in this and similar regions.

The association of endophytic bacteria with their plant hosts has a beneficial effect for many different plant species. Our goal is to identify endophytic bacteria that improve the biomass production and the carbon sequestration potential of poplar trees ( Populus spp.) when grown in marginal soil and to gain an insight in the mechanisms underlying plant growth promotion. Members of the Gammaproteobacteria dominated a collection of 78 bacterial endophytes isolated from poplar and willow trees. As representatives for the dominant genera of endophytic gammaproteobacteria, we selected Enterobacter sp. strain 638, Stenotrophomonas maltophilia R551-3, Pseudomonas putida W619, and Serratia proteamaculans 568 for genome sequencing and analysis of their plant growth-promoting effects, including root development. Derivatives of these endophytes, labeled with gfp , were also used to study the colonization of their poplar hosts. In greenhouse studies, poplar cuttings ( Populus deltoides × Populus nigra DN-34) inoculated with Enterobacter sp. strain 638 repeatedly showed the highest increase in biomass production compared to cuttings of noninoculated control plants. Sequence data combined with the analysis of their metabolic properties resulted in the identification of many putative mechanisms, including carbon source utilization, that help these endophytes to thrive within a plant environment and to potentially affect the growth and development of their plant hosts. Understanding the interactions between endophytic bacteria and their host plants should ultimately result in the design of strategies for improved poplar biomass production on marginal soils as a feedstock for biofuels.

We investigated the accumulation and influence of bioavailable P (BAP) in sediments of a stream located in an agricultural area of the Lake Mendota watershed in Wisconsin, USA. During hydrologic events, the stream carried high concentrations of suspended sediment (up to 250 mg/l) and BAP (up to 2.5 mg/l). Bed sediments were highly enriched in BAP, as inventories of BAP in the top 10 cm of sediment ranged from 143 to 14,500 μg P/cm2. Space variations in BAP inventories were related to site-specific hydrodynamics and geochemical factors, including iron (Fe; r2 = 0.71) and aluminum (Al; r2 = 0.54) concentrations. Most sites behaved as potential sinks for dissolved reactive phosphate during hydrologic events and potential sources during base-flow periods. Through the combination of site-specific factors and geochemical controls, Dorn Creek modifies the amount, timing, and composition of P delivered from the watershed to downstream sites and water bodies.

Heart development is a complex process, involving temporally and spatially restricted morphogenic events that ultimately give rise to a multichambered heart. Discoidin domain receptors (DDRs) 1 and 2 are receptor tyrosine kinases which bind and are activated by multiple types of collagen, a structural protein found within the myocardium and valves of the heart. Both DDR1 and DDR2 are expressed in the developing heart, with DDR1 expression detected on both cardiac myocytes and fibroblasts, whereas DDR2 was only detected on fibroblasts. To date most studies examining DDRs during heart development have focused on the role of DDR2 in this process. DDR2 is upregulated on activated endothelial cells of cardiac cushions during epithelial-mesenchymal transformation associated with valve development. Inhibition of DDR2 results in incomplete transformation and a lack of mesenchymal cell formation in vitro; however, in vivo there appears to be a compensatory mechanism which allows for mesenchymal cell formation. DDR1 and DDR2 have both been implicated in fibroblast-mediated collagen remodeling. Additional studies are necessary to characterize the consequences of DDR1 or DDR2 deletion on cardiac function and to examine how these receptors may participate in matrix remodeling in cardiovascular disease.

Background Local natural laboratories, designated by us as the “Evolution Canyon” model, are excellent tools to study regional and global ecological dynamics across life. They present abiotic and biotic contrasts locally, permitting the pursuit of observations and experiments across diverse taxa sharing sharp microecological subdivisions. Higher solar radiation received by the “African savannah-like” south-facing slopes (AS) in canyons north of the equator than by the opposite “European maquis-like” north-facing slopes (ES) is associated with higher abiotic stress. Scorpions are a suitable taxon to study interslope biodiversity differences, associated with the differences in abiotic factors (climate, drought), due to their ability to adapt to dry environments. Methodology/Principal Findings Scorpions were studied by the turning stone method and by UV light methods. The pattern observed in scorpions was contrasted with similar patterns in several other taxa at the same place. As expected, the AS proved to be significantly more speciose regarding scorpions, paralleling the interslope patterns in taxa such as lizards and snakes, butterflies (Rhopalocera), beetles (families Tenebrionidae, Dermestidae, Chrysomelidae), and grasshoppers (Orthoptera). Conclusions/Significance Our results support an earlier conclusion stating that the homogenizing effects of migration and stochasticity are not able to eliminate the interslope intra- and interspecific differences in biodiversity despite an interslope distance of only 100 m at the “EC” valley bottom. In our opinion, the interslope microclimate selection, driven mainly by differences in insolance, could be the primary factor responsible for the observed interslope pattern.

Cardiac fibroblasts are organized into a three-dimensional network in the heart. This organization follows the endomysial weave network that surrounds groups of myocytes. Reverse transcriptase-polymerase chain reaction, Western blots, and immunohistochemistry were used to show that discoidin domain receptor 2 (DDR2) was specific for cardiac fibroblasts and not expressed on endothelial cells, smooth muscle cells, or cardiac myocytes. DDR2 is expressed early in development and in the adult heart. High voltage electron microscopy (HVEM), scanning electron microscopy, and laser scanning confocal microscopy document the three-dimensional organization of fibroblasts in the heart. Antibodies against connexin 43 and 45 showed different patterns but confirmed, along with HVEM, that fibroblasts are connected to each other as well as cardiac myocytes. The implications of this arrangement of fibroblasts can be important to cardiac function. The signaling of DDR2 and the expression of matrix metalloproteinase 2 in relation to collagen turnover and remodeling is discussed.

Enterobacter sp. 638 is an endophytic plant growth promoting gamma-proteobacterium that was isolated from the stem of poplar (Populus trichocarpa×deltoides cv. H11-11), a potentially important biofuel feed stock plant. The Enterobacter sp. 638 genome sequence reveals the presence of a 4,518,712 bp chromosome and a 157,749 bp plasmid (pENT638-1). Genome annotation and comparative genomics allowed the identification of an extended set of genes specific to the plant niche adaptation of this bacterium. This includes genes that code for putative proteins involved in survival in the rhizosphere (to cope with oxidative stress or uptake of nutrients released by plant roots), root adhesion (pili, adhesion, hemagglutinin, cellulose biosynthesis), colonization/establishment inside the plant (chemiotaxis, flagella, cellobiose phosphorylase), plant protection against fungal and bacterial infections (siderophore production and synthesis of the antimicrobial compounds 4-hydroxybenzoate and 2-phenylethanol), and improved poplar growth and development through the production of the phytohormones indole acetic acid, acetoin, and 2,3-butanediol. Metabolite analysis confirmed by quantitative RT–PCR showed that, the production of acetoin and 2,3-butanediol is induced by the presence of sucrose in the growth medium. Interestingly, both the genetic determinants required for sucrose metabolism and the synthesis of acetoin and 2,3-butanediol are clustered on a genomic island. These findings point to a close interaction between Enterobacter sp. 638 and its poplar host, where the availability of sucrose, a major plant sugar, affects the synthesis of plant growth promoting phytohormones by the endophytic bacterium. The availability of the genome sequence, combined with metabolome and transcriptome analysis, will provide a better understanding of the synergistic interactions between poplar and its growth promoting endophyte Enterobacter sp. 638. This information can be further exploited to improve establishment and sustainable production of poplar as an energy feedstock on marginal, non-agricultural soils using endophytic bacteria as growth promoting agents., Author Summary Poplar is considered as the model tree species for the production of lignocellulosic biomass destined for biofuel production. The plant growth promoting endophytic bacterium Enterobacter sp. 638 can improve the growth of poplar on marginal soils by as much as 40%. This prompted us to sequence the genome of this strain and, via comparative genomics, identify functions essential for the successful colonization and endophytic association with its poplar host. Analysis of the genome sequence, combined with metabolite analysis and quantitative PCR, pointed to a remarkable interaction between Enterobacter sp. 638 and its poplar host with the endophyte responsible for the production of a phytohormone, and a precursor for another that poplar is unable to synthesize, and where the production of the plant growth promoting compounds depended on the presence of plant synthesized compounds, such as sucrose, in the growth medium. Our results provide the basis to better understanding the synergistic interactions between poplar and Enterobacter sp. 638. This information can be further exploited to improve establishment and sustainable production of poplar on marginal, non-agricultural soils using endophytic bacteria such as Enterobacter sp. 638 as growth promoting agents.

Special Topic: Babies, Boys, and Men of Color; International audience