The dynamic consequences of invasion: negative plant-soil feedbacks on natives increase ver the time course of invasion

*a) Background/Questions/Methods*
Exotic species can negatively impact native community members, directly through interference competition, or indirectly by altering interactions between native species and other species such as pathogens and mutualists. Soil microbial communities have been shown to respond to invasive species, yet are relatively stable and may take time to respond to perturbations. For this reason, microbe-mediated effects of invasives on natives may take time to develop and may change throughout the invasion process. Few studies have investigated how species interactions between natives and exotics change during invasions.

_Acer platanoides_ was introduced into the US from Europe in 1756 and has since invaded intact forests, lowering understory diversity and inhibiting native tree species regeneration. We hypothesize that _A. platanoides_ invasion will decrease seedling survival in the native _A. saccharum_ by changing the soil microbial community through plant-soil feedbacks (PSF), and this relationship will intensify over the course of an invasion. We collected soil samples from beneath the canopies of both species co-occurring in Michigan forests that had been invaded by _A. platanoides_ for varying time periods. In the greenhouse, we inoculated seedlings of both species with the microbial communities to determine how the soil community affects seedling survival and growth.

*b) Results/Conclusion*
The microbe-mediated negative effects of _A. platanoides_ on survival of the native congener _A. saccharum_ increased with increasing invasion age (negative correlation between invasion age and _A. saccharum_ survival; r = -0.806, R^2^ = 0.65, p = 0.032). This result was not related to _A. platanoides_ density, suggesting that age of invasion drives this pattern. Contrastingly, invasion age did not significantly influence survival of _A. platanoides_ seedlings, indicating that _A. platanoides’_ PSF impacts native species but not on conspecific regeneration. Overall, _A. platanoides_ seedlings had increased growth (more and larger leaves) when grown in soil communities collected from the native _A. saccharum_, but _A. saccharum_ seedlings had reduced growth when grown in conspecific soil (p = 0.044). These results suggest that invasive species may have increased performance in exotic ranges by their ability to modify the soil microbial community in a manner that suppresses the growth of native species.

We show the microbial community cultivated by an invader alters the performance of a native plant species, and this effect increases over the course of an invasion. In future work, we plan to identify changes in microbial community composition and the relative abundances of mutualists versus antagonists in response to invasion to identify potential mechanisms

The Uropathogenic Escherichia coli Effector YbcL Modulates the Innate Immune Response in the Urinary Tract

Uropathogenic Escherichia coli (UPEC) are the primary etiology of urinary tract infections (UTIs), one of the most common bacterial infections afflicting the human population. While UPEC cause disease throughout the urinary tract, bladder infection, or cystitis, is most prevalent. A key aspect of UPEC pathogenesis in the bladder is the modulation of the host inflammatory response. At acute time points, UPEC delay the arrival of immune cells, such as neutrophils, to the bladder. The lack of neutrophils in the bladder lumen enables UPEC to replicate freely in the urine and invade the bladder epithelium, a requirement for bacterial persistence, in the absence of immune pressure. The UPEC products responsible for delaying the arrival of immune cells to the bladder had not been identified. This thesis work identified a bacterial protein, YbcL, that was modestly up-regulated upon UPEC exposure to either cultured bladder epithelial cells or human neutrophils. We demonstrated that YbcL suppressed the migration of neutrophils across bladder epithelia in an in vitro model of transuroepithelial neutrophil migration and an in vivo murine model of cystitis. Suppression of PMN migration by YbcL was dependent upon the presence of threonine at position 78 (T78). In fact, T78 in YbcL is highly conserved in clinical UPEC isolates, suggesting that inhibition of neutrophil migration across epithelial barriers by YbcL is a conserved mechanism of immune modulation among UPEC. Using a number of complementary approaches, we demonstrated that liberation of YbcL from the bacterial periplasm was required for suppression of neutrophil migration across a bladder epithelium. YbcL was detected in the supernatant and in association with bladder epithelial cells and neutrophils. Release of YbcL from the periplasm occurred in a manner that was dependent upon the concentration of YbcL in the periplasm, the duration of the infection and the presence of bladder epithelial cells. Although YbcL was soluble in the supernatant, we demonstrated that YbcL was not secreted from the periplasm by a canonical secretion system. Despite the apparent absence of a dedicated secretion system, these findings demonstrate that YbcL functions as an exoprotein. Investigations into the mechanism underlying suppression of neutrophil migration by YbcL revealed that YbcL did not influence the production of chemoattractant molecules by bladder epithelial cells or bacteria or the ability of neutrophils to chemotax in response to stimuli, requirements for neutrophils to traverse epithelial barriers. This work identified and began the characterization of a bacterial protein, YbcL, that contributes to modulation of the innate immune response by UPEC. Additional experimentation is required to elucidate the importance of T78, the mode of delivery of YbcL from the periplasm, and the mechanism of action of YbcL. By delaying the arrival of immune cells, the activity of YbcL likely facilitates formation of the acute intracellular niche occupied by UPEC and required for persistence in the urinary tract

Synthesis and functionalisation of various magnetic nanoparticles for enzyme immobilisation and cascade reactions

Enzymes can be considered as sustainable catalysts due to their high activities with lower energy requirements while being derived from renewable resources. Enzymes have shown high chemo-, regio- and enantioselectivity which allows for higher conversion efficiencies and reduction in waste generation. However, they can be sensitive to the reaction environment and can denature when used beyond their normal operating conditions. To improve their operational stability, immobilisation of enzymes on a solid support can be adapted. This would also allow for the possibility of continuous processing, ease of separation, recyclability and recovery. Magnetic nanoparticles (MNPs) provide an elegant solution for enzyme immobilisation because of their high surface area to volume ratio, enhanced separation/recovery using an external magnetic field and easily modifiable surface. This thesis investigates enzyme immobilisation using Fe3O4 MNPs through covalent binding and NiFe2O4 MNPs via his-tag immobilisation. Initially a model protein and enzyme are immobilised onto a (3-aminopropyl)triethoxysilane (APTES) functionalised Fe3O4 MNPs by covalently binding the protein/enzyme to the available amine group. Then using NiFe2O4 MNPs, two enzymes halomonas elongata omega transaminase (HeωT) and D-phenylglycine transaminase (D-phgAT) are immobilised through their available his-tags. The application of NiFe2O4 MNPs was taken further and used in a one pot purification and immobilisation of HeωT, D-phgAT and Bacillus subtilis glucose dehydrogenase (Bs-GDH) directly from cell lysates. Finally, a free and immobilised tri-enzymatic system for the production of a 1-phenylethanol from s-methylbenzyl amine using HeωT, GDH and alcohol dehydrogenase (ADH) from saccharomyces cerevisiae is studied. Generally, the studies carried out are shown to be successful and highlight the versatility of MNPs for enzyme immobilisation especially how easily they can be separated, recycled and recovered.Engineering and Physical Sciences Research Council (EPSRC) CRITICAT CDT fundin

Sharing and Preserving Computational Analyses for Posterity with encapsulator

Open data and open-source software may be part of the solution to science's "reproducibility crisis", but they are insufficient to guarantee reproducibility. Requiring minimal end-user expertise, encapsulator creates a "time capsule" with reproducible code in a self-contained computational environment. encapsulator provides end-users with a fully-featured desktop environment for reproducible research.Comment: 11 pages, 6 figure

A Simulation Activity to Assess Student Pharmacists\u27 Knowledge and Perceptions of Oncology Pharmacy

Objective. To assess the impact of an interactive activity on student pharmacists’ confidence in answering oncology-related questions and their perceptions of an oncology pharmacists’ roles in practice. Methods. Two cohorts (2016 and 2017) of third-year student pharmacists completed a two-hour, interactive, four-station activity during the fourth week of an oncology module. Each station simulated a different oncology-related scenario that represented a specific practice settings. Pre- and post-activity surveys were administered to determine changes in students’ confidence levels and perceptions. Results. Over the two years, 66 student pharmacists completed the pre- and post-activity survey instruments. In both cohorts, there was a significant increase in scores on all items regarding students’ confidence. Student pharmacists’ perceptions of pharmacists\u27 roles also improved significantly. Conclusion. The simulation activity was effective as confirmed by improvement in student pharmacists’ post-activity scores on confidence and perception. Determining student pharmacists’ comfort in responding to oncology scenarios is important to prepare them for practice in any setting

Achieving change in primary care—causes of the evidence to practice gap : systematic reviews of reviews

Acknowledgements The Evidence to Practice Project (SPCR FR4 project number: 122) is funded by the National Institute of Health Research (NIHR) School for Primary Care Research (SPCR). KD is part-funded by the National Institute for Health Research (NIHR) Collaborations for Leadership in Applied Research and Care West Midlands and by a Knowledge Mobilisation Research Fellowship (KMRF-2014-03-002) from the NIHR. This paper presents independent research funded by the National Institute of Health Research (NIHR). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. Funding This study is funded by the National Institute for Health Research (NIHR) School for Primary Care Research (SPCR).Peer reviewedPublisher PD

Valores motivacionales y autoatribución de comportamientos socialmente responsables en estudiantes del Programa de Estudios Básicos de la Universidad Ricardo Palma 2017

Se partió del supuesto de que existe una relación significativa entre los valores humanos y la autoatribución de comportamientos socialmente responsables de los estudiantes del Programa de Estudios Básicos de la Universidad Ricardo Palma. El diseño de la investigación es no experimental, ex post facto, en base a un muestreo probabilístico de tamaño n= 353 (185 hombres y 168 mujeres; rango de edad: 16-21 años), de una población de 4297 estudiantes. Se aplicó el Cuestionario de valores por retratos (PVQ), de Schwartz (2006) y el cuestionario de auto-atribución de comportamientos socialmente responsables diseñado y validado para esta investigación. Para probar la hipótesis se diseñó un modelo sustentado en el marco teórico que diagnosticara la influencia de los valores en los comportamientos socialmente responsables, basado en el análisis de las estructuras de covarianzas y de correlaciones de las variables latentes y las variables observables. Con los datos, se comprobó que el modelo teórico de las relaciones causales entre los valores y los comportamientos socialmente responsables es un modelo adecuado. El modelo permite concluir que existe una correlación positiva y significativa (r=0.550, p_valor<0.05) entre los valores y la auto-atribución de frecuencias de comportamientos socialmente responsables.Trabado de investigacio

Bacterial lysis liberates the neutrophil migration suppressor YbcL from the periplasm of uropathogenic Escherichia coli

Uropathogenic Escherichia coli (UPEC) modulates aspects of the innate immune response during urinary tract infection to facilitate bacterial invasion of the bladder epithelium, a requirement for the propagation of infection. For example, UPEC-encoded YbcL suppresses the traversal of bladder epithelia by neutrophils in both an in vitro model and an in vivo murine cystitis model. The suppressive activity of YbcL requires liberation from the bacterial periplasm, though the mechanism of release is undefined. Here we present findings on the site of action of YbcL and demonstrate a novel mode of secretion for a UPEC exoprotein. Suppression of neutrophil migration by purified YbcL(UTI), encoded by cystitis isolate UTI89, required the presence of a uroepithelial layer; YbcL(UTI) did not inhibit neutrophil chemotaxis directly. YbcL(UTI) was released to a greater extent during UPEC infection of uroepithelial cells than during that of neutrophils. Release of YbcL(UTI) was maximal when UPEC and bladder epithelial cells were in close proximity. Established modes of secretion, including outer membrane vesicles, the type II secretion system, and the type IV pilus, were dispensable for YbcL(UTI) release from UPEC. Instead, YbcL(UTI) was liberated during bacterial death, which was augmented upon exposure to bladder epithelial cells, as confirmed by detection of bacterial cytoplasmic proteins and DNA in the supernatant and enumeration of bacteria with compromised membranes. As YbcL(UTI) acts on the uroepithelium to attenuate neutrophil migration, this mode of release may represent a type of altruistic cooperation within a UPEC population during colonization of the urinary tract

Esterase Variants in Four Species of the Paramecium aurelia Complex 1

One hundred eighty-eight stocks of Paramecium primaurelia, P. biaurelia, P. tetraurelia , and P. octaurelia were grown axenically and tested for five esterases, visualized by starch gel electrophoresis, in a search for variant stocks. The five esterases can be distinguished on the bases of their substrate specificity, sensitivity to an inhibitor, and response to different growth conditions. This paper addresses the nature of the electrophoretic change in mobility of the variant stocks in order that species relationships can be more accurately assessed. Crosses carried out in all four species show that single genes determine the differences in mobility between variant and common subtypes. Extracts of variant stocks that gave similar patterns were run against each other, tested for their sensitivity to the inhibitor, and the pattern was compared to that found in extracts of stocks with variant and common subtypes in other species. The majority of the variants in P. primaurelia, P. tetraurelia , and P. octaurelia show an electrophoretic mobility characteristic of a common subtype, or a variant, in another species. The same proportion of variant subtypes as common subtypes have mobilities similar to esterase subtypes found in other species. Of the four species examined in this paper, P. tetraurelia and P. octaurelia appear to be most closely related on the basis of shared esterase subtypes. In P. biaurelia the mobilities of most of the variants are unique, as are the common esterase subtypes in this species. P. biaurelia stands out as having the greatest number of esterase subtypes, with very few of them homologous to subtypes found in other species. This observation supports the idea of greater diversification of stocks within P. biaurelia than for the other three species.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75741/1/j.1550-7408.1982.tb01346.x.pd

Managing for Change: Achieving Systemic Reform Through the Effective Implementation of Networks for School Improvement

In August 2018, the Bill & Melinda Gates Foundation (“the foundation”) launched its Networks for School Improvement (NSIs) initiative. To further its own continuous learning as well as the learning of its grantees and the educational field, the foundation engaged the Center for Public Research and Leadership (CPRL) to conduct a formative evaluation of the NSIs initiative during its first two years. The research questions that guided this study were: How are network hubs implementing the Network for School Improvement (NSI) strategy? What are the characteristics of effective networks and network hubs? To answer these questions, CPRL used a qualitative research design to deeply explore the work of nine networks representative of the broader pool of grantees. Selection was designed to ensure diversity with respect to the following characteristics: (a) geographic location, (b) number of schools in the network, (c) number of districts in the network, (d) grade band targeted, and (e) problem of practice. The findings presented in this paper emerge from an analysis of data collected from these networks across two years. In total, CPRL conducted over 160 interviews, observed 22 network convenings, and analyzed nearly 1,000 artifacts and documents