Spatial and Temporal Immune Response in House Flies in Response to Ingestion of Bacillus Cereus and Eschericha Coli 0157-H7

House flies (Musca domestica L.) feed and breed on septic substrates, putting them in direct contact with a multitude of disease causing agents and can act as a bridge for those agents to humans. The house fly has previously been shown to carry many different species of bacteria that are pathogenic. Escherichia coli O157:H7 is a pathogenic enterohemorrhagic serotype of E. coli that can be vectored by the house fly. Bacillus cereus is a foodborne pathogen that has also been isolated from the house fly in previous studies. To examine vector potential for these pathogens, house flies were fed green fluorescent protein (GFP)-expressing E. coli 157:H7 or B. cereus and then bacterial fate and localization of fly defensive responses were analyzed at various hours post-ingestion (h PI). Bacterial fate was assessed qualitatively by localizing bacteria via microscopy and quantitatively by culturing whole fly homogenate. House fly defensive responses, including three antimicrobial peptides (AMPs; Defensin, Diptericin, and Cecropin) and the peptidoglycan cleaving enzyme Lysozyme, were analyzed using immunofluorescent localization. Localization of B. cereus and E. coli O157:H7 at various time points correlated with evidence of lysed bacteria in microscopy, a decrease in recovered bacteria, and observed expression of AMPs and Lysozyme. Bacterial recovery showed that B. cereus decreased steadily up to 24 h PI and E. coli O157:H7 decreased steadily up to 12 h PI. Flies fed B. cereus induced Defensin, Diptericin, and Lysozyme expression that peaked in the midgut at 6 h PI. In contrast, flies fed E. coli O157:H7 showed noticeable expression of only Lysozyme and Diptericin at 2 and 6 h PI in the midgut and proventriculus. This study shows that B. cereus elicits a strong immune response from the house fly and can persist in the gut until 24 h PI, while E. coli O157:H7 elicits little immune response and can persist up to 12 h PI. These findings help to define whether or not pathogenic bacteria can survive at infectious levels within the fly, how the house fly responds to ingestion of these pathogens, and finally how long the bacteria can persist within the fly

Advances in the molecular classification of pediatric brain tumors: a guide to the galaxy

Central nervous system (CNS) tumors are the most common solid tumor in pediatrics, accounting for approximately 25% of all childhood cancers, and the second most common pediatric malignancy after leukemia. CNS tumors can be associated with significant morbidity, even those classified as low grade. Mortality from CNS tumors is disproportionately high compared to other childhood malignancies, although surgery, radiation, and chemotherapy have improved outcomes in these patients over the last few decades. Current therapeutic strategies lead to a high risk of side effects, especially in young children. Pediatric brain tumor survivors have unique sequelae compared to age-matched patients who survived other malignancies. They are at greater risk of significant impairment in cognitive, neurological, endocrine, social, and emotional domains, depending on the location and type of the CNS tumor. Next-generation genomics have shed light on the broad molecular heterogeneity of pediatric brain tumors and have identified important genes and signaling pathways that serve to drive tumor proliferation. This insight has impacted the research field by providing potential therapeutic targets for these diseases. In this review, we highlight recent progress in understanding the molecular basis of common pediatric brain tumors, specifically low-grade glioma, high-grade glioma, ependymoma, embryonal tumors, and atypical teratoid/rhabdoid tumor (ATRT). © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd

The Resummed Photon Spectrum in Radiative Upsilon Decays

We present a theoretical prediction for the photon spectrum in radiative Upsilon decay including the effects of resumming the endpoint region, E_\gamma -> M_\Upsilon/2. Our approach is based on NRQCD and the soft collinear effective theory. We find that our results give much better agreement with data than the leading order NRQCD prediction.Comment: 4 pages, 6 figure

Resummation of Large Endpoint Corrections to Color-Octet J/psi Photoproduction

An unresolved problem in J/psi phenomenology is a systematic understanding of the differential photoproduction cross section, dsigma/dz [gamma + p -> J/psi + X], where z= E_psi/E_gamma in the proton rest frame. In the non-relativistic QCD (NRQCD) factorization formalism, fixed-order perturbative calculations of color-octet mechanisms suffer from large perturbative and nonperturbative corrections that grow rapidly in the endpoint region, z -> 1. In this paper, NRQCD and soft collinear effective theory are combined to resum these large corrections to the color-octet photoproduction cross section. We derive a factorization theorem for the endpoint differential cross section involving the parton distribution function and the color-octet J/psi shape functions. A one loop matching calculation explicitly confirms our factorization theorem at next-to-leading order. Large perturbative corrections are resummed using the renormalization group. The calculation of the color-octet contribution to dsigma/dz is in qualitative agreement with data. Quantitative tests of the universality of color-octet matrix elements require improved knowledge of shape functions entering these calculations as well as resummation of the color-singlet contribution which accounts for much of the total cross section and also peaks near the endpoint.Comment: 30 pages, 6 figure

Linear and nonlinear optical properties of silica aerogel

Scattering media have traditionally been seen as a hindrance to the controlled transport of light through media, creating the familiar speckle pattern. However such matter does not cause the loss of information but instead performs a highly complex deterministic operation on the incoming flux. Through sculpting the properties of the incoming wavefront, we can unlock the hidden characteristics of these media, affording us far more degrees of freedom than that which is available to us in traditional ballistic optics. These additional degrees of freedom have allowed for the creation of compact sophisticated optical devices based only on the deterministic nature of light scattering. Such devices include diffraction-limit-beating lenses, polarimeters, spectrometers, and some which can transmit entire images through a scattering substance. Additional degrees of freedom would allow for the creation of even more powerful devices, in new working regimes. In particular, the application of related techniques where the scattering material is actively modified is limited. This thesis is concerned with the use of optothermal nonlinearity in random media as a way to provide an additional degree of control over light which scatters through it. Specifically, we are concerned with silica aerogel as a platform for this study. Silica aerogel is a lightweight skeletal structure of silica fibrils, which results in a material which is up to 99.98 % by volume. This material exhibits a unique cocktail of properties of use such as near unitary refractive index, an order of magnitude lower thermal conductivity, and high optothermal nonlinearity. The latter two of these properties allow for the creation of localised steep thermal gradients, proportionally affecting the low refractive index significantly. Additionally through differing fabrication steps, the opacity, and as a result, we can adjust the scattering strength. In line with the development of light deterministic light scattering techniques in linear media, we develop through the use of pump-probe setups, a framework for the development of a similar line of techniques in nonlinear scattering media. We show that we can reversibly control the far-field propagation of light in weakly scattering silica aerogel. Following this, we show that nonlinear perturbation can be used to extend and modify the optical memory effect, where slight adjustments in scattering direction maintain the overall correlation of the scattered profile. Finally, we measure the nonlinear transmission matrix, a complete description of how any wavefront would pass through at a particular point in a scattering media, and how that scattering can be modified through the application of an optothermal nonlinearity. Extending the tool of scattering media into the nonlinear regime helps pave the way toward the next set of advances in the field of light scattering control."This work was supported by the Engineering and Physical Sciences Research Council [grant number EP/M508214/1]" -- Fundin

Exclusive Radiative Decays of Upsilon in SCET

We study exclusive radiative decays of the $\Upsilon$ using soft-collinear effective theory and non-relativistic QCD. In contrast to inclusive radiative decays at the endpoint we find that color-octet contributions are power suppressed in exclusive decays, and can safely be neglected, greatly simplifying the analysis. We determine the complete set of Lorentz structures that can appear in the SCET Wilson coefficients and match onto them using results from a previous calculation. We run these coefficients from the scale \mups to the scale $\Lambda \sim 1 \textrm{GeV}$, thereby summing large logarithms. Finally we use our results to predict the ratio of branching fractions $B(\Upsilon \to \gamma f_2)/B(J/\psi \to \gamma f_2)$, $B(J/\psi \to \gamma f_2)/B(\psi' \to \gamma f_2)$, and the partial rate for $\Upsilon \to \gamma \pi \pi$.Comment: 17 pages, 2 figures. Updated to reflect published versio

The Systematics of Quarkonium Production at the LHC and Double Parton Fragmentation

In this paper we discuss the systematics of quarkonium production at the LHC. In particular, we focus on the necessity to sum logs of the form log(Q/p_perp) and log(p_perp/m_Q). We show that the former contributions are power suppressed, while the latter, whose contribution in fragmentation is well known, also arise in the short distance (i.e., non-fragmentation) production mechanisms. Though these contributions are suppressed by powers of m_Q/p_perp, they can be enhanced by inverse powers of v, the relative velocity between heavy quarks in the quarkonium. In the limit p_perp >> m_Q short distance production can be thought of as the fragmentation of a pair of partons (i.e., the heavy quark and anti-quark) into the final state quarkonium. We derive an all order factorization theorem for this process in terms of double parton fragmentation functions (DPFF) and calculate the one-loop anomalous dimension matrix for the DPFF.Comment: 27 pages, 11 figure