1,336 results on '"S. Perkins"'
Search Results
2. Response of Acala Cotton to Nitrogen Rates in the San Joaquin Valley of California
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R.B. Hutmacher, R.L. Travis, R.L. Nichols, D.E. Rains, B.A. Roberts, B.L. Weir, R. M. Vargas, B. H. Marsh, S. D. Wright, D. S. Munk, D. J. Munier, M. P. Keeley, F. Fritschi, R. L. Delgado, and S. Perkins
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Technology ,Medicine ,Science - Abstract
The responses of Acala cotton (Gossypium hirsutum L.) in California to a range of applied nitrogen (N) treatments were investigated in a 5-year, multisite experiment. The experiment’s goals were to identify crop growth and yield responses to applied N and provide information to better assess the utility of soil residual N estimates in improving fertilizer management. Baseline fertilizer application rates for the lowest applied N treatments were based on residual soil nitrate-N (NO3-N) levels determined on soil samples from the upper 0.6 m of the soil collected prior to spring N fertilization and within 1 week postplanting each year. Results have shown positive cotton lint yield responses to increases in applied N across the 56 to 224 kg N/ha range in only 41% (16 out of 39) of test sites. Soil NO3-N monitoring to a depth of 2.4 m in the spring (after planting) and fall (postharvest) indicate most changes in soil NO3- occur within the upper 1.2 m of soil. However, some sites (those most prone to leaching losses of soluble nutrients) also exhibited net increases in soil NO3-N in the 1.2- to 2.4-m depth zone when comparing planting time vs. postharvest data. The lack of yield responses and soil NO3-N accumulations at some sites indicate that more efforts should be put into identifying the amount of plant N requirements that can be met from residual soil N, rather than solely from fertilizer N applications.
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- 2001
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3. Report from the IAB Workshop on Environmental Impact of Internet Applications and Systems, 2022.
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Jari Arkko, Colin S. Perkins, and Suresh Krishnan
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- 2024
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4. WNT5B drives osteosarcoma stemness, chemoresistance and metastasis
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Rachel S. Perkins, Glenn Murray, Sarocha Suthon, Lindsey Davis, Nicholson B. Perkins III, Lily Fletcher, Amanda Bozzi, Saylor L. Schreiber, Jianjian Lin, Steven Laxton, Rahul R. Pillai, Alec J. Wright, Gustavo A. Miranda‐Carboni, and Susan A. Krum
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cancer stem cells ,metastasis ,osteosarcoma ,WNT5B ,Medicine (General) ,R5-920 - Abstract
Abstract Background Treatment for osteosarcoma, a paediatric bone cancer with no therapeutic advances in over three decades, is limited by a lack of targeted therapies. Osteosarcoma frequently metastasises to the lungs, and only 20% of patients survive 5 years after the diagnosis of metastatic disease. We found that WNT5B is the most abundant WNT expressed in osteosarcoma tumours and its expression correlates with metastasis, histologic subtype and reduced survival. Methods Using tumor‐spheroids to model cancer stem‐like cells, we performed qPCR, immunoblotting, and immunofluorescence to monitor changes in gene and protein expression. Additionally, we measured sphere size, migration and forming efficiency to monitor phenotypic changes. Therefore, we characterised WNT5B's relevance to cancer stem‐like cells, metastasis, and chemoresistance and evaluated its potential as a therapeutic target. Results In osteosarcoma cell lines and patient‐derived spheres, WNT5B is enriched in stem cells and induces the expression of the stemness gene SOX2. WNT5B promotes sphere size, sphere‐forming efficiency, and cell proliferation, migration, and chemoresistance to methotrexate (but not cisplatin or doxorubicin) in spheres formed from conventional cell lines and patient‐derived xenografts. In vivo, WNT5B increased osteosarcoma lung and liver metastasis and inhibited the glycosaminoglycan hyaluronic acid via upregulation of hyaluronidase 1 (HYAL1), leading to changes in the tumour microenvironment. Further, we identified that WNT5B mRNA and protein correlate with the receptor ROR1 in primary tumours. Targeting WNT5B through inhibition of WNT/ROR1 signalling with an antibody to ROR1 reduced stemness properties, including chemoresistance, sphere size and SOX2 expression. Conclusions Together, these data define WNT5B's role in driving osteosarcoma cancer stem cell expansion and methotrexate resistance and provide evidence that the WNT5B pathway is a promising candidate for treating osteosarcoma patients. Key points WNT5B expression is high in osteosarcoma stem cells leading to increased stem cell proliferation and migration through SOX2. WNT5B expression in stem cells increases rates of osteosarcoma metastasis to the lungs and liver in vivo. The hyaluronic acid degradation enzyme HYAL1 is regulated by WNT5B in osteosarcoma contributing to metastasis. Inhibition of WNT5B with a ROR1 antibody decreases osteosarcoma stemness.
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- 2024
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5. Report from the IAB Workshop on Environmental Impact of Internet Applications and Systems, 2022
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Arkko, J., primary, S. Perkins, C., additional, and Krishnan, S., additional
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- 2024
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6. The nutritional value of meat should be considered when comparing the carbon footprint of lambs produced on different finishing diets
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Louise C. McNicol, Lynda S. Perkins, James Gibbons, Nigel D. Scollan, Anne P. Nugent, Eleri M. Thomas, Elizabeth L. Swancott, Colin McRoberts, Alison White, Simon Chambers, Linda Farmer, and A. Prysor Williams
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sheep systems ,farm management ,fatty acids ,human nutrition ,environmental impacts of meat ,Omega-3 ,Nutrition. Foods and food supply ,TX341-641 ,Food processing and manufacture ,TP368-456 - Abstract
IntroductionLamb production systems are under increasing pressure to reduce their environmental footprint, particularly emissions of greenhouse gases (GHGs) such as methane. However, the metrics used to express the carbon footprint of lamb seldom consider its nutritional density and contribution to balanced diets in humans. Lamb production systems vary considerably, from low-input pastoral systems to higher-input systems feeding concentrates for the latter ‘finishing’ period. To date, no studies have explored the effect of finishing diet on the carbon footprint of lamb meat on a nutritional basis.MethodsData from 444 carcasses were collected from four abattoirs across Wales, United Kingdom. Lambs were derived from 33 farms with one of four distinct finishing diets: forage crops (n = 5), grass (n = 11), concentrates (n = 7), and grass and concentrates (n = 15). Carcass data were analysed using mixed effects models. Significant differences were found in fatty acid composition of two large commercial cuts of meat from different finishing diets. To illustrate the effect of different measures of footprint, mass (kg dwt) and omega-3 polyunsaturated fatty acid content (g omega-3) were selected as functional units. GHG emission estimates were calculated using Agrecalc.ResultsThe concentrates diet had the lowest average mass-based product emissions [25.0 kg CO2e/kg deadweight (dwt)] while the grass systems had the highest (28.1 kg CO2e/kg dwt; p < 0.001). The semimembranosus muscle cut from the forage crops diet had the lowest average nutrition-based product emissions (19.2 kg CO2e/g omega-3); whereas the same muscle cut from lambs finished on the grass and concentrates diet had the highest nutrition-based product emissions (29.4 kg CO2e/g omega-3; p < 0.001).DiscussionWhile mass-based functional units can be useful for comparing efficiencies of different farming systems, they do not reflect how farming systems impact the nutritional differences of the final product. This study demonstrates the importance of considering nutrition when expressing and comparing the carbon footprints of nutrient-dense foods such as lamb. This approach could also help inform discussions around the optimal diets for lamb production systems from both a human nutrition and environmental sustainability perspective.
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- 2024
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7. Percutaneous creation of a choledocho-choledochostomy for intractable iatrogenic bile duct injury
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Rui Dai, Charles Y. Kim, Debra L. Sudan, Scott S. Perkins, James W. Tamas, and Paul V. Suhocki
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Internal medicine ,RC31-1245 ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Published
- 2023
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8. Estimating the Impact of Climate and Vegetation Changes on Runoff Risk across the Hawaiian Landscape
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Lucas Berio Fortini, Lauren R. Kaiser, Kim S. Perkins, Lulin Xue, and Yaping Wang
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infiltration ,excess rainfall ,rainfall intensity ,runoff ,ecohydrology ,Ecology ,QH540-549.5 - Abstract
In Hawai’i, ecosystem conservation practitioners are increasingly considering the potential ecohydrological benefits from applied conservation action to mitigate the degrading impacts of runoff on native and restored ecosystems. One determinant of runoff is excess rainfall events where rainfall rates exceed the infiltration capacity of soils. To help understand runoff risks, we calculated the probability of excess rainfall events across the Hawaiian landscape by comparing the probability distributions of projected rainfall frequency and land-cover-specific infiltration capacity. We characterized soil infiltration capacity based on different land cover types (bare soil, grasses, and woody vegetation) and compared them to the frequency of large rainfall events under current and future climate scenarios. We then mapped the potential risk of excess rainfall across the main Hawaiian Islands. Our results show that land cover type has a very large effect on runoff risk as excess rainfall conditions are 234% more likely in bare soil and 75% more likely in grasslands compared to woody forests and shrublands. In contrast, projected shifts in rainfall intensity by end-of-century show little impact on these probabilities and thus, the risk of runoff. This indicates that the probability of excess rainfall is primarily driven by differences in land cover and not by current or potential shifts in rainfall patterns across the Hawaiian landscape. The ability to estimate the risk of potentially ecologically and economically costly runoff based on changes of land cover is useful for managers focused on invasive species control and restoration planning, especially for native and endemic ecosystems unique to the State of Hawai’i.
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- 2023
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9. ‘Listen to my heart’: Qualitative researchers and people living with rheumatic heart disease collaborate to direct future RHD research
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C Read, A Mitchell, T D Johnson, M E Engel, O Mathshabane, I Ssinabulya, A Scheel, T Erio, J Lawrenson, S Perkins, J de Vries, and L Zühlke
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rheumatic heart disease ,Medicine ,Medicine (General) ,R5-920 - Abstract
Background. Rheumatic heart disease (RHD) is a preventable chronic cardiac condition that causes over 350 000 deaths annually, largely in low and middle-income countries, as a direct result of structural inequalities and inadequate access to comprehensive healthcare. People living with and affected by this disease are a key stakeholder group and need to be directing research priorities. Objective. To improve care and provide direction for future research, a group of qualitative researchers and pe living with RHD from six countries convened in Cape Town in 2016. Methods. People with RHD shared their lived experiences while RHD researchers, clinicians and advocates presented a spectrum of qualitative research methods to explore these experiences. The Continuum of Care© (CoC, developed by the Medtronic Foundation) was used as a framework to guide participant discussions. Thematic summaries of the discussions were undertaken in an iterative process throughout the workshop. Results. Three themes emerged in the summaries: there is no ‘typical’ patient journey; a biomedical focus on RHD does not reflect people’s lived experiences; and a diversity of research methods is required to investigate experiences of people living with RHD. Practice implications. Qualitative research methods are invaluable for allowing patient ‘voices’ to be heard. To this end, qualitative approaches should be incorporated in all RHD research to ensure maximum benefit for patients. Conclusion. Greater understanding of the patient journey was gained for strengthening and expanding the global RHD research agenda. Future research should reflect on and incorporate the realities of patients’ lived experiences, and these experiences should be integrated into healthcare models for chronic conditions.
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- 2023
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10. Report from the IAB Workshop on Analyzing IETF Data (AID) 2021.
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Niels ten Oever, Corinne Cath, Mirja Kühlewind, and Colin S. Perkins
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- 2022
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11. Modeling Post‐Wildfire Hydrologic Response: Review and Future Directions for Applications of Physically Based Distributed Simulation
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Brian A. Ebel, Zachary M. Shephard, Michelle A. Walvoord, Sheila F. Murphy, Trevor F. Partridge, and Kim S. Perkins
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wildfire ,wildland fire ,hydrologic model ,streamflow ,groundwater ,water supply ,Environmental sciences ,GE1-350 ,Ecology ,QH540-549.5 - Abstract
Abstract Wildfire is a growing concern as climate shifts. The hydrologic effects of wildfire, which include elevated hazards and changes in water quantity and quality, are increasingly assessed using numerical models. Post‐wildfire application of physically based distributed models provides unique insight into the underlying processes that affect water resources after wildfire. This work reviews and synthesizes post‐wildfire applications of physically based distributed models by examining the scales and geographic/ecohydrologic distribution of model applications, hydrologic response process representation, model parameterization, and model performance metrics. Highlighted gaps and opportunities for advancing physically based distributed hydrologic response modeling after wildfire include the following: (a) applying models in under‐represented geographic (S. America, Africa, Asia) and ecohydrologic regions (arid or dry subhumid climates), (b) incorporating all four major streamflow generation mechanisms (infiltration excess, saturation excess, subsurface storm flow, and groundwater flow), (c) representing integrated vadose zone and saturated zone processes to better capture subsurface streamflow generation, (d) building new remotely sensed model parameterization methods for precipitation interception, infiltration, and overland flow that account for burn severity and recovery, (e) incorporating distributed state variables (e.g., soil moisture, groundwater levels) in model performance assessment, (f) designing model intercomparison studies, including field datasets specifically for post‐wildfire model development and validation, (g) linking mechanistic vegetation regrowth models with hydrologic models to improve simulation of process shifts as ecosystems recover, and (h) creating a new community modeling framework to integrate modeling advances across the wildfire science community.
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- 2023
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12. The role of WNT10B in physiology and disease: A 10-year update
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Rachel S. Perkins, Rishika Singh, Amy N. Abell, Susan A. Krum, and Gustavo A. Miranda-Carboni
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WNT10B ,Wnt ,Wnt signaling ,bone ,disease ,cancer ,Biology (General) ,QH301-705.5 - Abstract
WNT10B, a member of the WNT family of secreted glycoproteins, activates the WNT/β-catenin signaling cascade to control proliferation, stemness, pluripotency, and cell fate decisions. WNT10B plays roles in many tissues, including bone, adipocytes, skin, hair, muscle, placenta, and the immune system. Aberrant WNT10B signaling leads to several diseases, such as osteoporosis, obesity, split-hand/foot malformation (SHFM), fibrosis, dental anomalies, and cancer. We reviewed WNT10B a decade ago, and here we provide a comprehensive update to the field. Novel research on WNT10B has expanded to many more tissues and diseases. WNT10B polymorphisms and mutations correlate with many phenotypes, including bone mineral density, obesity, pig litter size, dog elbow dysplasia, and cow body size. In addition, the field has focused on the regulation of WNT10B using upstream mediators, such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). We also discussed the therapeutic implications of WNT10B regulation. In summary, research conducted during 2012–2022 revealed several new, diverse functions in the role of WNT10B in physiology and disease.
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- 2023
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13. Regulation and Function of FOXC1 in Osteoblasts
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Sarocha Suthon, Jianjian Lin, Rachel S. Perkins, Gustavo A. Miranda-Carboni, and Susan A. Krum
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FOXC1 ,GATA4 ,osteoblast ,estrogen ,Biology (General) ,QH301-705.5 - Abstract
Estrogens, which bind to estrogen receptor alpha (ERα), are important for proper bone mineral density. When women go through menopause, estrogen levels decrease, and there is a decrease in bone quality, along with an increased risk for fractures. We previously identified an enhancer near FOXC1 as the most significantly enriched binding site for estrogen receptor alpha (ERα) in osteoblasts. FOXC1 is a transcription factor belonging to a large group of proteins known as forkhead box genes and is an important regulator of bone formation. Here, we demonstrate that 17β-estradiol (E2) increases the mRNA and protein levels of FOXC1 in primary mouse and human osteoblasts. GATA4 is a pioneer factor for ERα and it is also recruited to enhancers near Foxc1. Knockdown of Gata4 in mouse osteoblasts in vitro decreases Foxc1 expression as does knockout of Gata4 in vivo. Functionally, GATA4 and FOXC1 interact and regulate osteoblast proteins such as RUNX2, as demonstrated by ChIP-reChIP and luciferase assays. The most enriched motif in GATA4 binding sites from ChIP-seq is for FOXC1, supporting the notion that GATA4 and FOXC1 cooperate in regulating osteoblast differentiation. Together, these data demonstrate the interactions of the transcription factors ERα, GATA4, and FOXC1 to regulate each other’s expression and other osteoblast differentiation genes.
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- 2023
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14. Upregulation of an estrogen receptor-regulated gene by first generation progestins requires both the progesterone receptor and estrogen receptor alpha
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Meghan S. Perkins, Renate Louw-du Toit, Hayley Jackson, Mishkah Simons, and Donita Africander
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breast cancer ,estrogen receptor ,menopausal hormone therapy ,progesterone receptor ,progestins ,steroid receptor crosstalk ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Progestins, synthetic compounds designed to mimic the activity of natural progesterone (P4), are used globally in menopausal hormone therapy. Although the older progestins medroxyprogesterone acetate (MPA) and norethisterone (NET) have been implicated in increased breast cancer risk, little is known regarding newer progestins, and no significant risk has been associated with P4. Considering that breast cancer is the leading cause of mortality in women, establishing which progestins increase breast cancer incidence and elucidating the underlying mechanisms is a global priority. We showed for the first time that the newer-generation progestin drospirenone (DRSP) is the least potent progestin in terms of proliferation of the estrogen-responsive MCF-7 BUS breast cancer cell line, while NET and P4 have similar potencies to estradiol (E2), the known driver of breast cancer cell proliferation. Notably, MPA, the progestin most frequently associated with increased breast cancer risk, was significantly more potent than E2. While all the progestogens enhanced the anchorage-independent growth of the MCF-7 BUS cell line, MPA promoted a greater number of colonies than P4, NET or DRSP. None of the progestogens inhibited E2-induced proliferation and anchorage-independent growth. We also showed that under non-estrogenic conditions, MPA and NET, unlike P4 and DRSP, increased the expression of the estrogen receptor (ER) target gene, cathepsin D, via a mechanism requiring the co-recruitment of ERα and the progesterone receptor (PR) to the promoter region. In contrast, all progestogens promoted the association of the PR and ERα on the promoter of the PR target gene, MYC, thereby increasing its expression under non-estrogenic and estrogenic conditions. These results suggest that progestins differentially regulate the way the PR and ER converge to modulate the expression of PR and ER-regulated genes. Our novel findings indicating similarities and differences between P4 and the progestins, emphasize the importance of comparatively investigating effects of individual progestins rather than grouping them as a class. Further studies are required to underpin the clinical relevance of PR/ERα crosstalk in response to different progestins in both normal and malignant breast tissue, to either confirm or refute their suitability in combination therapy for ER-positive breast cancer.
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- 2022
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15. Performance analysis of single board computer clusters.
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Philip James Basford, Steven J. Johnston, Colin S. Perkins, Tony Garnock-Jones, Fung Po Tso 0001, Dimitrios Pezaros, Robert D. Mullins, Eiko Yoneki, Jeremy Singer, and Simon J. Cox 0001
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- 2020
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16. The Fermi-LAT Lightcurve Repository
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S. Abdollahi, M. Ajello, L. Baldini, J. Ballet, D. Bastieri, J. Becerra Gonzalez, R. Bellazzini, A. Berretta, E. Bissaldi, R. Bonino, A. Brill, P. Bruel, E. Burns, S. Buson, R. A. Cameron, R. Caputo, P. A. Caraveo, N. Cibrario, S. Ciprini, P. Cristarella Orestano, M. Crnogorcevic, S. Cutini, F. D’Ammando, S. De Gaetano, S. W. Digel, N. Di Lalla, L. Di Venere, A. Domínguez, V. Fallah Ramazani, S. J. Fegan, E. C. Ferrara, A. Fiori, H. Fleischhack, A. Franckowiak, Y. Fukazawa, P. Fusco, V. Gammaldi, F. Gargano, S. Garrappa, C. Gasbarra, D. Gasparrini, N. Giglietto, F. Giordano, M. Giroletti, D. Green, I. A. Grenier, S. Guiriec, M. Gustafsson, E. Hays, D. Horan, X. Hou, G. Jóhannesson, M. Kerr, D. Kocevski, M. Kuss, L. Latronico, J. Li, I. Liodakis, F. Longo, F. Loparco, L. Lorusso, B. Lott, M. N. Lovellette, P. Lubrano, S. Maldera, A. Manfreda, G. Martí-Devesa, M. N. Mazziotta, I. Mereu, M. Meyer, P. F. Michelson, T. Mizuno, M. E. Monzani, A. Morselli, I. V. Moskalenko, M. Negro, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, G. Panzarini, J. S. Perkins, M. Persic, M. Pesce-Rollins, R. Pillera, T. A. Porter, G. Principe, J. L. Racusin, S. Rainò, R. Rando, B. Rani, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, M. Sánchez-Conde, P. M. Saz Parkinson, Jeff Scargle, L. Scotton, D. Serini, C. Sgrò, E. J. Siskind, G. Spandre, P. Spinelli, D. J. Suson, H. Tajima, D. J. Thompson, D. F. Torres, J. Valverde, T. Venters, Z. Wadiasingh, S. Wagner, and K. Wood
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Gamma-ray astronomy ,Active galactic nuclei ,Light curves ,Astrophysics ,QB460-466 - Abstract
The Fermi Large Area Telescope (LAT) lightcurve repository (LCR) is a publicly available, continually updated library of gamma-ray lightcurves of variable Fermi-LAT sources generated over multiple timescales. The Fermi-LAT LCR aims to provide publication-quality lightcurves binned on timescales of 3, 7, and 30 days for 1525 sources deemed variable in the source catalog of the first 10 yr of Fermi-LAT observations. The repository consists of lightcurves generated through full likelihood analyses that model the sources and the surrounding region, providing fluxes and photon indices for each time bin. The LCR is intended as a resource for the time-domain and multimessenger communities by allowing users to search LAT data quickly to identify correlated variability and flaring emission episodes from gamma-ray sources. We describe the sample selection and analysis employed by the LCR and provide an overview of the associated data access portal.
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- 2023
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17. Report from the IAB Workshop on Analyzing IETF Data (AID) 2021
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ten Oever, N., primary, Cath, C., additional, Kühlewind, M., additional, and S. Perkins, C., additional
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- 2022
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18. Through Death to Rebirth
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James S. Perkins
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- 2020
19. Reduced neutralisation of the Delta (B.1.617.2) SARS-CoV-2 variant of concern following vaccination.
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Chris Davis, Nicola Logan, Grace Tyson, Richard Orton, William T Harvey, Jonathan S Perkins, Guy Mollett, Rachel M Blacow, COVID-19 Genomics UK (COG-UK) Consortium, Thomas P Peacock, Wendy S Barclay, Peter Cherepanov, Massimo Palmarini, Pablo R Murcia, Arvind H Patel, David L Robertson, John Haughney, Emma C Thomson, Brian J Willett, and COVID-19 DeplOyed VaccinE (DOVE) Cohort Study investigators
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Vaccines are proving to be highly effective in controlling hospitalisation and deaths associated with SARS-CoV-2 infection but the emergence of viral variants with novel antigenic profiles threatens to diminish their efficacy. Assessment of the ability of sera from vaccine recipients to neutralise SARS-CoV-2 variants will inform the success of strategies for minimising COVID19 cases and the design of effective antigenic formulations. Here, we examine the sensitivity of variants of concern (VOCs) representative of the B.1.617.1 and B.1.617.2 (first associated with infections in India) and B.1.351 (first associated with infection in South Africa) lineages of SARS-CoV-2 to neutralisation by sera from individuals vaccinated with the BNT162b2 (Pfizer/BioNTech) and ChAdOx1 (Oxford/AstraZeneca) vaccines. Across all vaccinated individuals, the spike glycoproteins from B.1.617.1 and B.1.617.2 conferred reductions in neutralisation of 4.31 and 5.11-fold respectively. The reduction seen with the B.1.617.2 lineage approached that conferred by the glycoprotein from B.1.351 (South African) variant (6.29-fold reduction) that is known to be associated with reduced vaccine efficacy. Neutralising antibody titres elicited by vaccination with two doses of BNT162b2 were significantly higher than those elicited by vaccination with two doses of ChAdOx1. Fold decreases in the magnitude of neutralisation titre following two doses of BNT162b2, conferred reductions in titre of 7.77, 11.30 and 9.56-fold respectively to B.1.617.1, B.1.617.2 and B.1.351 pseudoviruses, the reduction in neutralisation of the delta variant B.1.617.2 surpassing that of B.1.351. Fold changes in those vaccinated with two doses of ChAdOx1 were 0.69, 4.01 and 1.48 respectively. The accumulation of mutations in these VOCs, and others, demonstrate the quantifiable risk of antigenic drift and subsequent reduction in vaccine efficacy. Accordingly, booster vaccines based on updated variants are likely to be required over time to prevent productive infection. This study also suggests that two dose regimes of vaccine are required for maximal BNT162b2 and ChAdOx1-induced immunity.
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- 2021
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20. Next generation single board clusters.
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Jeremy Singer, Herry Herry, Philip James Basford, Wajdi Hajji, Colin S. Perkins, Fung Po Tso 0001, Dimitrios Pezaros, Robert D. Mullins, Eiko Yoneki, Simon J. Cox 0001, and Steven J. Johnston
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- 2018
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21. Commodity single board computer clusters and their applications.
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Steven J. Johnston, Philip James Basford, Colin S. Perkins, Herry Herry, Fung Po Tso 0001, Dimitrios Pezaros, Robert D. Mullins, Eiko Yoneki, Simon J. Cox 0001, and Jeremy Singer
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- 2018
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22. Improving the Low-energy Transient Sensitivity of AMEGO-X using Single-site Events
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I. Martinez-Castellanos, Henrike Fleischhack, C. Karwin, M. Negro, D. Tak, Amy Lien, C. A. Kierans, Zorawar Wadiasingh, Yasushi Fukazawa, Marco Ajello, Matthew G. Baring, E. Burns, R. Caputo, Dieter H. Hartmann, Jeremy S. Perkins, Judith L. Racusin, and Yong Sheng
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- 2022
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23. The POEMMA (Probe of Extreme Multi-Messenger Astrophysics) Observatory
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A. V. Olinto, J. Krizmanic, J. H. Adams, R. Aloisio, L. A. Anchordoqui, M. Bagheri, D. Barghini, M. Battisti, D. R. Bergman, M. E. Bertaina, P. F. Bertone, F. Bisconti, M. Bustamante, M. Casolino, K. Cerny, M. J. Christi, A. L. Cummings, I. de Mitri, R. Diesing, R. Engel, J. Eser, K. Fang, F. Fenu, G. Filippatos, E. Gazda, C. Guepin, A. Haungs, E. A. Hays, E. G. Judd, P. Klimov, V. Kungel, E. Kuznetsov, S. Mackovjak, D. Mandat, L. Marcelli, J. McEnery, G. Medina-Tanco, K. -D. Merenda, S. S. Meyer, J. W. Mitchell, H. Miyamoto, J. M. Nachtman, A. Neronov, F. Oikonomou, Y. Onel, A. N. Otte, E. Parizot, T. Paul, M. Pech, J. S. Perkins, P. Picozza, L. W. Piotrowski, Z. Plebaniak, G. Prevot, P. Reardon, M. H. Reno, M. Ricci, O. Romero Matamala, F. Sarazin, P. Schovanek, K. Shinozaki, J. F. Soriano, F. Stecker, Y. Takizawa, R. Ulrich, M. Unger, T. M. Venters, L. Wiencke, D. Winn, R. M. Young, and M. Zotov
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Astrophysics - Abstract
The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) is designed to accurately observe ultra-high-energy cosmic rays (UHECRs) and cosmic neutrinos from space with sensitivity over the full celestial sky. POEMMA will observe the air fluorescence produced by extensive air showers (EASs) from UHECRs and potentially UHE neutrinos above 20 EeV. Additionally, POEMMA has the ability to observe the Cherenkov signal from upward-moving EASs induced by Earth-interacting tau neutrinos above 20 PeV. The POEMMA spacecraft are designed to quickly re-orientate to follow up transient neutrino sources and obtain currently unparalleled neutrino flux sensitivity. Developed as a NASA Astrophysics Probe-class mission, POEMMA consists of two identical satellites flying in loose formation in 525 km altitude orbits. Each POEMMA instrument incorporates a wide field-of-view (45°) Schmidt telescope with an optical collecting area of over 6 sq. m. The hybrid focal surface of each telescope includes a fast (1 μs) near-ultraviolet camera for EAS fluorescence observations and an ultrafast (10 ns) optical camera for Cherenkov EAS observations. In a 5-year mission, POEMMA will provide measurements that open new multi-messenger windows onto the most energetic events in the universe, enabling the study of new astrophysics and particle physics at these extreme energies.
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- 2021
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24. Multiresolution HEALPix Maps for Multiwavelength and Multimessenger Astronomy
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I. Martinez-Castellanos, Leo P. Singer, E. Burns, D. Tak, Alyson Joens, Judith L. Racusin, and Jeremy S. Perkins
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- 2022
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25. Synthesis, Structure, and Hydrolytic Activation of Ruthenium (III)-Pyrazole Complex
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Mylene Planques, Arushi Shyam, Richard S. Perkins, Frank R. Fronczek, and Radhey S. Srivastava
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Article Subject ,General Chemistry - Abstract
We report here the synthesis of water-soluble mer-[RuCl3(DMSO-S) (pyz)2] 2 prepared by the reaction of mer-RuCl3(DMSO-S)31 with pyrazole in anhydrous CH2Cl2. Compound 2 was characterized by IR and UV-visible spectroscopy, X-ray diffraction, cyclic voltammetry, and DFT calculations. The X-ray diffraction analysis disclosed that compound 2 has two independent molecules present in the asymmetric unit with different conformations for one of the pyrazoles and different hydrogen bonding. The DFT calculations suggest the structure-activity relationship and hydrolytic activity of these complexes.
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- 2022
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26. BurstCube: A CubeSat for Gravitational Wave Counterparts
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Jeremy S Perkins, Isabella Brewer, Michael S Briggs, Alessandro Bruno, Eric Burns, Regina Caputo, Brad Cenko, Antonino Cucchiara, Georgia de Nolfo, Jeff Dumonthier, Sean Griffin, Lorraine Hanlon, Dieter H Hartmann, Boyan Hristov, Michelle Hui, Alyson Joens, Carolyn Kierans, Marc Kippen, Dan Kocevski, John Krizmanic, Sibasish Laha, Amy Lien, Israel Martinez-Castellanos, Sheila McBreen, Julie E McEnery, J G Mitchell, Lee Mitchell, David Morris, David Murphy, Judith L Racusin, Oliver Roberts, Peter Shawhan, Jacob R Smith, George Suarez, Teresa Tatoli, Alexey Uliyanov, Carlos Vazquez, Sarah Walsh, and Colleen Wilson-hodge
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Astronomy - Published
- 2020
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27. Fermi Large Area Telescope Fourth Source Catalog
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S. Abdollahi, F. Acero, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, J. Becerra Gonzalez, R. Bellazzini, A. Berretta, E. Bissaldi, R. D. Blandford, E. D. Bloom, R. Bonino, E. Bottacini, T. J. Brandt, J. Bregeon, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, R. A. Cameron, R. Caputo, P. A. Caraveo, J. M. Casandjian, D. Castro, E. Cavazzuti, E. Charles, S. Chaty, S. Chen, C. C. Cheung, G. Chiaro, S. Ciprini, J. Cohen-Tanugi, L. R. Cominsky, J. Coronado-Blázquez, D. Costantin, A. Cuoco, S. Cutini, F. D'Ammando, M. DeKlotz, P. de la Torre Luque, F. de Palma, A. Desai, S. W. Digel, N. Di Lalla, M. Di Mauro, L. Di Venere, A. Dominguez, D. Dumora, F. Fana Dirirsa, S. J. Fegan, E. C. Ferrara, A. Franckowiak, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, D. Green, I. A. Grenier, S. Griffin, M.-H. Grondin, J. E. Grove, S. Guiriec, A. K. Harding, K. Hayashi, E. Hays, J. W. Hewitt, D. Horan, G. Jóhannesson, T. J. Johnson, T. Kamae, M. Kerr, D. Kocevski, M. Kovac’evic’, M. Kuss, D. Landriu, S. Larsson, L. Latronico, M. Lemoine-Goumard, J. Li, I. Liodakis, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, S. Maldera, D. Malyshev, A. Manfreda, E. J. Marchesini, L. Marcotulli, G. Martí-Devesa, P. Martin, F. Massaro, M. N. Mazziotta, J. E. McEnery, I. Mereu, M. Meyer, P. F. Michelson, N. Mirabal, T. Mizuno, M. E. Monzani, A. Morselli, I. V. Moskalenko, M. Negro, E. Nuss, R. Ojha, N. Omodei, M. Orienti, E. Orlando, J. F. Ormes, M. Palatiello, V. S. Paliya, D. Paneque, Z. Pei, H. Peña-Herazo, J. S. Perkins, M. Persic, M. Pesce-Rollins, V. Petrosian, L. Petrov, F. Piron, H. Poon, T. A. Porter, G. Principe, S. Raino', R. Rando, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, Q. Remy, T. Reposeur, R. W. Romani, P. M. Saz Parkinson, F. K. Schinzel, D. Serini, C. Sgro', E. J. Siskind, D. A. Smith, G. Spandre, P. Spinelli, A. W. Strong, D. J. Suson, H. Tajima, M. N. Takahashi, D. Tak, J. B. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, E. Torresi, J. Valverde, B. Van Klaveren, P. van Zyl, K. Wood, M. Yassine, and G. Zaharijas
- Subjects
Astrophysics - Abstract
We present the fourth Fermi Large Area Telescope catalog (4FGL) of gamma-ray sources. Based on the first eight years of science data from the Fermi Gamma-ray Space Telescope mission in the energy range from 50 MeV to 1 TeV, it is the deepest yet in this energy range. Relative to the 3FGL catalog, the 4FGL catalog has twice as much exposure as well as a number of analysis improvements, including an updated model for the Galactic diffuse gamma-ray emission, and two sets of light curves (one-year and two-month intervals). The 4FGL catalog includes 5064 sources above 4 sigma significance, for which we provide localization and spectral properties. Seventy-five sources are modeled explicitly as spatially extended, and overall, 358 sources are considered as identified based on angular extent, periodicity, or correlated variability observed at other wavelengths. For 1336 sources, we have not found plausible counterparts at other wavelengths. More than 3130 of the identified or associated sources are active galaxies of the blazar class, and 239 are pulsars.
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- 2020
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28. Is Explicit Congestion Notification usable with UDP?
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Stephen McQuistin and Colin S. Perkins
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- 2015
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29. GATA4 and estrogen receptor alpha bind at SNPs rs9921222 and rs10794639 to regulate AXIN1 expression in osteoblasts
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Sarocha Suthon, Rachel S. Perkins, Jianjian Lin, John R. Crockarell, Gustavo A. Miranda-Carboni, and Susan A. Krum
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Genetics ,Genetics (clinical) - Published
- 2022
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30. AstroPix: Status and Outlook of Monolithic Active Pixel Sensors for Future Gamma-ray Telescopes
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Caputo, Regina, primary, L Steinhebel, Amanda, additional, Fleischhack, Henrike, additional, Striebig, Nicolas, additional, Jadhav, Manoj, additional, Suda, Yusuke, additional, Luz, Ricardo, additional, Violette, Daniel, additional, Kierans, Carolyn, additional, Tajima, Hiroyasu, additional, Fukazawa, Yasushi, additional, Leys, Richard, additional, Peric, Ivan, additional, Metcalfe, Jessica, additional, Negro, Michela, additional, and S Perkins, Jeremy, additional
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- 2023
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31. Estrogen receptor alpha and NFATc1 bind to a bone mineral density-associated SNP to repress WNT5B in osteoblasts
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Sarocha Suthon, Jianjian Lin, Rachel S. Perkins, John R. Crockarell, Gustavo A. Miranda-Carboni, and Susan A. Krum
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Polymorphism, Single Nucleotide ,Article ,Histones ,Mice ,Bone Density ,Osteogenesis ,Databases, Genetic ,Genetics ,Animals ,Humans ,Alleles ,Cells, Cultured ,Genetics (clinical) ,Adipogenesis ,Binding Sites ,Osteoblasts ,NFATC Transcription Factors ,Estrogen Receptor alpha ,Cell Differentiation ,Immunohistochemistry ,Wnt Proteins ,Gene Expression Regulation ,Gene Knockdown Techniques ,Female ,Genome-Wide Association Study ,Protein Binding ,Signal Transduction - Abstract
Genetic factors and estrogen deficiency contribute to the development of osteoporosis. The single-nucleotide polymorphism (SNP) rs2887571 is predicted from genome-wide association studies (GWASs) to associate with osteoporosis but has had an unknown mechanism. Analysis of osteoblasts from 110 different individuals who underwent joint replacement revealed that the genotype of rs2887571 correlates with WNT5B expression. Analysis of our ChIP-sequencing data revealed that SNP rs2887571 overlaps with an estrogen receptor alpha (ERα) binding site. Here we show that 17β-estradiol (E2) suppresses WNT5B expression and further demonstrate the mechanism of ERα binding at the enhancer containing rs2887571 to suppress WNT5B expression differentially in each genotype. ERα interacts with NFATc1, which is predicted to bind directly at rs2887571. CRISPR-Cas9 and ChIP-qPCR experiments confirm differential regulation of WNT5B between each allele. Homozygous GG has a higher binding affinity for ERα than homozygous AA and results in greater suppression of WNT5B expression. Functionally, WNT5B represses alkaline phosphatase expression and activity, decreasing osteoblast differentiation and mineralization. Furthermore, WNT5B increases interleukin-6 expression and suppresses E2-induced expression of alkaline phosphatase during osteoblast differentiation. We show that WNT5B suppresses the differentiation of osteoblasts via receptor tyrosine kinase-like orphan receptor 1/2 (ROR1/2), which activates DVL2/3/RAC1/CDC42/JNK/SIN3A signaling and inhibits β-catenin activity. Together, our data provide mechanistic insight into how ERα and NFATc1 regulate the non-coding SNP rs2887571, as well as the function of WNT5B on osteoblasts, which could provide alternative therapeutic targets for osteoporosis.
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- 2022
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32. The Fermi-LAT Light Curve Repository
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S. Abdollahi, M. Ajello, L. Baldini, J. Ballet, D. Bastieri, J. Becerra Gonzalez, R. Bellazzini, A. Berretta, E. Bissaldi, R. Bonino, A. Brill, P. Bruel, E. Burns, S. Buson, R. A. Cameron, R. Caputo, P. A. Caraveo, N. Cibrario, S. Ciprini, P. Cristarella Orestano, M. Crnogorcevic, S. Cutini, F. D’Ammando, S. De Gaetano, S. W. Digel, N. Di Lalla, L. Di Venere, A. Domínguez, V. Fallah Ramazani, S. J. Fegan, E. C. Ferrara, A. Fiori, H. Fleischhack, A. Franckowiak, Y. Fukazawa, P. Fusco, V. Gammaldi, F. Gargano, S. Garrappa, C. Gasbarra, D. Gasparrini, N. Giglietto, F. Giordano, M. Giroletti, D. Green, I. A. Grenier, S. Guiriec, M. Gustafsson, E. Hays, D. Horan, X. Hou, G. Jóhannesson, M. Kerr, D. Kocevski, M. Kuss, L. Latronico, J. Li, I. Liodakis, F. Longo, F. Loparco, L. Lorusso, B. Lott, M. N. Lovellette, P. Lubrano, S. Maldera, A. Manfreda, G. Martí-Devesa, M. N. Mazziotta, I. Mereu, M. Meyer, P. F. Michelson, T. Mizuno, M. E. Monzani, A. Morselli, I. V. Moskalenko, M. Negro, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, G. Panzarini, J. S. Perkins, M. Persic, M. Pesce-Rollins, R. Pillera, T. A. Porter, G. Principe, J. L. Racusin, S. Rainò, R. Rando, B. Rani, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, M. Sánchez-Conde, P. M. Saz Parkinson, Jeff Scargle, L. Scotton, D. Serini, C. Sgrò, E. J. Siskind, G. Spandre, P. Spinelli, D. J. Suson, H. Tajima, D. J. Thompson, D. F. Torres, J. Valverde, T. Venters, Z. Wadiasingh, S. Wagner, K. Wood, and UAM. Departamento de Física Teórica
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Active galactic nuclei ,Light Curves (918) ,Gamma-ray astronomy ,Space and Planetary Science ,Física ,FOS: Physical sciences ,Gamma-ray astronomy, Active galactic nuclei, Light curves, Astrophysics - High Energy Astrophysical Phenomena ,Gamma-Ray Astronomy (628) ,Astronomy and Astrophysics ,Active Galactic Nuclei (16) ,Light curves ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboración, si lo hubiere, The Fermi Large Area Telescope (LAT) lightcurve repository (LCR) is a publicly available, continually updated library of gamma-ray lightcurves of variable Fermi-LAT sources generated over multiple timescales. The Fermi-LAT LCR aims to provide publication-quality lightcurves binned on timescales of 3, 7, and 30 days for 1525 sources deemed variable in the source catalog of the first 10 yr of Fermi-LAT observations. The repository consists of lightcurves generated through full likelihood analyses that model the sources and the surrounding region, providing fluxes and photon indices for each time bin. The LCR is intended as a resource for the time-domain and multimessenger communities by allowing users to search LAT data quickly to identify correlated variability and flaring emission episodes from gamma-ray sources. We describe the sample selection and analysis employed by the LCR and provide an overview of the associated data access portal, M.N. and J.V. acknowledge that the material is based upon work supported by NASA under award number 80GSFC21M0002. D.K. and M.N. acknowledge support to this work from NASA Fermi GI Program under grant number 80NSSC23K0242. A.B. is supported by the NASA Postdoctoral Program at NASA Goddard Space Flight Center, administered by Oak Ridge Associated Universities. INFN and ASI personnel performed in part under ASI-INFN Agreements No. 2021-43-HH.0. Work at NRL is supported by NASA. The Fermi-LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat à l’Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucléaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K. A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica in Italy and the Centre National d’Études Spatiales in France. This work performed in part under DOE Contract DE-AC02-76SF00515
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- 2023
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33. UZIG Research: Measurement and Characterization of Unsaturated Zone Processes under Wide-Ranging Climates and Changing Conditions
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Jared J. Trost, Kimberlie S. Perkins, Wesley Henson, Benjamin B. Mirus, John R. Nimmo, and Rafael Muñoz-Carpena
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Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Unsaturated zone properties and processes are central to understanding the interacting effects of land-use change, contamination, and hydroclimate on our ability to grow food, sustain clean water supplies, and minimize loss of life and property. Advances in unsaturated zone science are being achieved through collaborations across traditional boundaries where information from biological, physical, and chemical disciplines is combined for new insights. The Unsaturated Zone Interest Group (UZIG) is an organization that exists principally to promote multidisciplinary collaborations and the sharing of ideas, expertise, and technical assets. Here we summarize key findings from 14 papers, several of which originated from a meeting convened by UZIG in 2017 at the University of Florida in Gainesville titled “Land-Use Change, Climate Change, and Hydrologic Extremes: Unsaturated Zone Responses and Feedbacks.” This special section of contains multidisciplinary research in three general categories relevant to measuring and understanding unsaturated zone responses to changing land uses and climate: (i) unsaturated zone properties and processes; (ii) soil–plant–atmosphere interactions; and (iii) novel field sampling devices. A strong cross-cutting theme in these papers is the value of continuous monitoring data and ways of utilizing them to discover novel hydrologic, biologic, and pedologic information. As climatic and land-use conditions change and demands for resources and stresses on ecosystems continue to intensify, it is vital to improve our fundamental understanding of the processes at work in the unsaturated zone. Toward that goal, we discuss the need for improved ground-based unsaturated zone monitoring networks.
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- 2018
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34. Automation of the Solution of Kakuro Puzzles.
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R. P. Davies, Paul A. Roach, and S. Perkins
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- 2008
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35. Synthesis, structure, and magnetic properties of the quaternary oxysulfides Ln 5V3O7S6 (Ln = La, Ce)
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Crystal Ferels, Jürgen Köhler, Chong Zheng, Reinhard K. Kremer, Arndt Simon, Roald Hoffmann, Roxanna Fotovat, Frank Calvagna, Alyssa Mohr, Kejun Bu, Timothy S. Perkins, and Fuqiang Huang
- Subjects
Crystallography ,Chemistry ,General Chemistry ,Quaternary - Abstract
Two rare earth oxysulfides Ln 5V3O7S6 (Ln = La, Ce) have been synthesized and their structures determined. The two isostructural compounds crystallize in the orthorhombic space group Pmmn (no. 59). The structure features one-dimensional edge-sharing VS4O2 octahedron chains parallel to the b axis. The bonding between V and S/O is covalent, and between Ln 3+ and the rest of the matrix ionic. Magnetic susceptibility measurement revealed that V is in a mixed valence state of V3+ and V4+. Its magnetic behavior follows the Curie-Weiss law.
- Published
- 2021
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36. (Z)-4-Chloro-N-{3-[(4-chlorophenyl)sulfonyl]-2,3-dihydrobenzo[d]thiazol-2-ylidene}benzenesulfonamide
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Sydney M. Watkins, Timothy J. Hagen, Timothy S. Perkins, and Chong Zheng
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crystal structure ,IspF inhibitor ,bis-sulfonamide ,Crystallography ,QD901-999 - Abstract
The title compound, C19H12Cl2N2O4S3, is related to a ditosylated 2-iminobenzothiazole with the two methyl groups on the two phenyl rings replaced by chlorine. There is a weak intramolecular π–π contact between the two phenyl rings, with a centroid-to-centroid distance of 4.004 (2) Å. The dihedral angle between the rings is 9.96 (13)°. An intramolecular C—H...O hydrogen bond stabilizes the molecular conformation.
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- 2017
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37. Report from the IAB Workshop on Analyzing IETF Data (AID) 2021
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N. ten Oever, C. Cath, M. Kühlewind, and C. S. Perkins
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- 2022
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38. Twist angle controlled collinear Edelstein effect in van der Waals heterostructures
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Alessandro Veneri, David T. S. Perkins, Csaba G. Péterfalvi, and Aires Ferreira
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Condensed Matter - Materials Science ,Condensed Matter - Mesoscale and Nanoscale Physics ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,ddc:530 ,Disordered Systems and Neural Networks (cond-mat.dis-nn) ,Condensed Matter - Disordered Systems and Neural Networks - Abstract
The generation of spatially homogeneous spin polarization by application of electric current is a fundamental manifestation of symmetry-breaking spin--orbit coupling (SOC) in solid-state systems, which underpins a wide range of spintronic applications. Here, we show theoretically that twisted van der Waals heterostructures with proximity-induced SOC are candidates par excellence to realize exotic spin-charge transport phenomena due to their highly tunable momentum-space spin textures. Specifically, we predict that graphene/group-VI dichalcogenide bilayers support room temperature spin--current responses that can be manipulated via twist-angle control. For critical twist angles, the non-equilibrium spin density is pinned parallel to the applied current. This effect is robust against twist-angle disorder, with graphene/$\text{WSe}_{2}$ possessing a critical angle (purely collinear response) of $\theta_{c} \simeq 14^{\circ}$. A simple electrical detection scheme to isolate the collinear Edelstein effect is proposed., Comment: 12 pages, 6 figures, includes supplemental material. Accepted version in Physical Review B Letters
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- 2022
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39. Phase slips and metastability in granular boron-doped nanocrystalline diamond microbridges
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Georgina M. Klemencic, Jonathan M. Fellows, Scott Manifold, M. Salman, Soumen Mandal, Sean Giblin, C. M. Muirhead, Oliver A. Williams, Robert A. Smith, and D. T. S. Perkins
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Josephson effect ,Materials science ,Nanowire ,Phase (waves) ,FOS: Physical sciences ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Superconductivity (cond-mat.supr-con) ,Condensed Matter::Superconductivity ,Metastability ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,General Materials Science ,Superconductivity ,Condensed Matter - Materials Science ,Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed matter physics ,Condensed Matter - Superconductivity ,Materials Science (cond-mat.mtrl-sci) ,General Chemistry ,021001 nanoscience & nanotechnology ,Microstructure ,0104 chemical sciences ,Slippage ,0210 nano-technology ,Coherence (physics) - Abstract
A phase slip is a localized disturbance in the coherence of a superconductor allowing an abrupt 2$\pi$ phase shift. Phase slips are a ubiquitous feature of one-dimensional superconductors and also have an analogue in two-dimensions. Here we present electrical transport measurements on boron-doped nanocrystalline diamond (BNCD) microbridges where, despite their three-dimensional macroscopic geometry, we find clear evidence of phase slippage in both the resistance-temperature and voltage-current characteristics. We attribute this behavior to the unusual microstructure of BNCD. We argue that the columnar crystal structure of BNCD forms an intrinsic Josephson junction array that supports a line of phase slippage across the microbridge. The voltage-state in these bridges is metastable and we demonstrate the ability to switch deterministically between different superconducting states by applying electromagnetic noise pulses. This metastability is remarkably similar to that observed in $\delta$-MoN nanowires, but with a vastly greater response voltage.
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- 2021
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40. Abstract 3527: WNT5B drives osteosarcoma stemness, metastasis and chemoresistance
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Rachel S. Perkins, Sarocha Suthon, Gustavo A. Miranda-Carboni, and Susan A. Krum
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Cancer Research ,Oncology - Abstract
Osteosarcoma is a pediatric bone cancer that has no targeted therapy and has had no treatment advances for the last three decades. Osteosarcoma frequently metastasizes to the lungs, reducing patient survival with metastatic disease to 20% after 5 years. The goal of this study is to describe the function of WNT5B and its signaling pathway in osteosarcoma stem cells, metastasis and chemoresistance and its potential as a therapeutic target. Using RNA sequencing from publicly available datasets and immunohistochemistry on tumor microarrays, we reveal that WNT5B is the most expressed WNT in osteosarcoma patients and correlates with both metastasis and survival. Osteosarcoma is thought to result from a block in differentiation, and based on WNT5B’s role in inhibiting osteoblast differentiation of mesenchymal stem cells from normal bone, we hypothesized a role for WNT5B in osteosarcoma stem cells. In spheroids, we show that both protein and mRNA levels of WNT5B are enhanced in the stem cell population compared to adherent cells. We found that WNT5B upregulates the expression of the stemness gene SOX2 and directs stemness phenotypes, such as sphere forming efficiency, proliferation and migration. We show a reduction in sphere forming efficiency with 143B-WNT5B-knockdown cells compared to parental control cells which can be rescued with re-introduction of WNT5B. Additionally, we show that WNT5B drives proliferation and migration of osteosarcoma stem cells through increasing sphere size and capability to migrate on collagen matrix. Further, WNT5B enhances osteosarcoma chemoresistance to methotrexate. Through revealing a novel role for WNT5B in osteosarcoma cancer stem cells and therapy resistance, we present the WNT5B pathway as a candidate for therapeutically targeting osteosarcoma stem cells in patients. Citation Format: Rachel S. Perkins, Sarocha Suthon, Gustavo A. Miranda-Carboni, Susan A. Krum. WNT5B drives osteosarcoma stemness, metastasis and 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 3527.
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- 2023
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41. Abstract 72: Ablation of WNT10B alters the tumor microenvironment in highly metastatic breast cancer, altering paclitaxel response
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Hannah R. Kelso, Rachel S. Perkins, Ikbale El Ayachi, Jackelyn A. Alva-Ornelas, Tiffany N. Seagroves, Victoria L. Seewaldt, Susan A. Krum, and Gustavo Adolfo Miranda-Carboni
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Cancer Research ,Oncology - Abstract
Triple-negative breast cancer (TNBC) has the worst survival outcome and the greatest incidence of metastasis among breast cancer subtypes. We have shown that the WNT10B network, composed of β-CATENIN, HMGA2, and EZH2, is predictive of higher rates of TNBC metastasis and poorer overall survival in TNBC. The stroma-tumor microenvironment (TME) interactions in metastatic breast cancer remain poorly defined, and prior to our work, the role of WNT10B signaling in the TME was unknown. Global gene expression profiling of the Wnt10bKO total mammary glands demonstrated a gene signature consistent with altered metabolism and markers promoting adipocyte differentiation. Wnt10b ablation in the mammary gland increases adipogenic differentiation and decreases the number of mammary gland terminal-end buds, and epithelia to stroma/fibroblast cell ratios. Therefore, we questioned the role of WNT10B in stromal cancer-associated fibroblast (CAFs) and cancer-associated adipocytes (CAAs) in the TME of transformed mammary glands. By backcrossing our Wnt10bKO mice to the highly metastatic MMTV-PyMT (PyMT) transgenic mammary tumor model, we demonstrated alteration in the age of tumor onset, changes in the incidence of transformation of thoracic and abdominal-inguinal tumors, and impacts on survival rates. Moreover, adipogenic markers are higher and persist through transformation in PyMTWnt10bKO mice compared to PyMT mice. Proliferation, migration, and invasion are also impacted in the PyMTWnt10bKO CAFs when co-cultured with PyMT tumor cells. The ability of PyMTWnt10bKO CAFs to alter cellular plasticity and generate CAAs is higher than PyMT CAFs. Additionally, PyMTWnt10bKO CAFs lose expression of canonical Wnt markers DVL and LRP and gain non-canonical Wnt signaling via WNT5B/ROR pathways that persist in the KO CAAs. We also observed alterations in chemoresistance in KO tumor epithelium. The resistance to paclitaxel from enriched PyMT epithelia from thoracic tumors was higher than epithelia enriched from the abdominal-inguinal tumors. Interestingly, the Wnt10bKO TME inverted the response to paclitaxel and the abdominal-inguinal epithelial tumor cells were more resistant than those from the thoracic epithelium. Furthermore, resistance to paclitaxel was associated with higher responses to PRI-724, a CBP-β-CATENIN inhibitor. Neither WT nor KO epithelial subtypes were resistant to olaparib exposure. Therefore, we conclude that Wnt10b is essential to educate highly metastatic breast cancer stromal cells to promote growth, metastatic colonization, and resistance to paclitaxel. Citation Format: Hannah R. Kelso, Rachel S. Perkins, Ikbale El Ayachi, Jackelyn A. Alva-Ornelas, Tiffany N. Seagroves, Victoria L. Seewaldt, Susan A. Krum, Gustavo Adolfo Miranda-Carboni. Ablation of WNT10B alters the tumor microenvironment in highly metastatic breast cancer, altering paclitaxel response [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 72.
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- 2023
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42. Landscape level effects of invasive plants and animals on water infiltration through Hawaiian tropical forests
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Makani Gregg, Lucas B. Fortini, Kim S. Perkins, Christina R. Leopold, Kai’ena I Bishaw, Stephanie G. Yelenik, Oliver A. Chadwick, and James D. Jacobi
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0106 biological sciences ,geography ,geography.geographical_feature_category ,Ungulate ,Ecology ,010604 marine biology & hydrobiology ,Community structure ,Groundwater recharge ,Biology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Grassland ,Invasive species ,Ecosystem services ,Infiltration (hydrology) ,Ecosystem ,Ecology, Evolution, Behavior and Systematics - Abstract
Watershed degradation due to invasion threatens downstream water flows and associated ecosystem services. While this topic has been studied across landscapes that have undergone invasive-driven state changes (e.g., native forest to invaded grassland), it is less well understood in ecosystems experiencing within-system invasion (e.g. native forest to invaded forest). To address this subject, we conducted an integrated ecological and ecohydrological study in tropical forests impacted by invasive plants and animals. We measured soil infiltration capacity in multiple fenced (i.e., ungulate-free)/unfenced and native/invaded forest site pairs along moisture and substrate age gradients across Hawaii to explore the effects of invasion on hydrological processes within tropical forests. We also characterized forest composition, structure and soil characteristics at these sites to assess the direct and vegetation-mediated impacts of invasive species on infiltration capacity. Our models show that invasive ungulates negatively affect soil infiltration capacity consistently across the wide moisture and substrate age gradients considered. Additionally, several soil characteristics known to be affected by invasive ungulates were associated with local infiltration rates, indicating that the long-term secondary effects of high ungulate densities in tropical forests may be stronger than effects observed in this study. The effect of invasive plants on infiltration was complex and likely to depend on their physiognomy within existing forest community structure. These results provide clear evidence for managers that invasive ungulate control efforts can improve ecohydrological function of mesic and wet forest systems critical to protecting downstream and nearshore resources and maintaining groundwater recharge.
- Published
- 2021
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43. PRELIMINARY RESULTS OF A PHASE 2 TRIAL OF OBINUTUZUMAB, IN COMBINATION WITH IFOSFAMIDE, CARBOPLATIN AND ETOPOSIDE (O-ICE) IN CHILDREN, ADOLESCENTS AND YOUNG ADULTS WITH RELAPSED/ REFRACTORY MATURE B-CELL NON-HODGKIN LYMPHOMA
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J. Hochberg, M. Cohen, M. Barth, L. Harrison, L. Klejmont, Q. Shi, S. Goldman, P. Galardy, S. Perkins, R. Miles, M. Lim, and M. Cairo
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Cancer Research ,Oncology ,Hematology - Published
- 2022
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44. When the Great Mimickers Mock Each Other: A Clinical Conundrum
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K. Kolbe, R. Zemans, J. Miller, Y. Engenda, and S. Perkins
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- 2022
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45. Cosmic-ray electron-positron spectrum from 7 GeV to 2 TeV with the Fermi Large Area Telescope
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S. Abdollahi, M. Ackermann, M. Ajello, W. B. Atwood, L. Baldini, G. Barbiellini, D. Bastieri, R. Bellazzini, E. D. Bloom, R. Bonino, T. J. Brandt, J. Bregeon, P. Bruel, R. Buehler, R. A. Cameron, R. Caputo, M. Caragiulo, D. Castro, E. Cavazzuti, C. Cecchi, A. Chekhtman, S. Ciprini, J. Cohen-Tanugi, F. Costanza, A. Cuoco, S. Cutini, F. D’Ammando, F. de Palma, R. Desiante, S. W. Digel, N. Di Lalla, M. Di Mauro, L. Di Venere, P. S. Drell, A. Drlica-Wagner, C. Favuzzi, W. B. Focke, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Giglietto, F. Giordano, M. Giroletti, D. Green, L. Guillemot, S. Guiriec, A. K. Harding, T. Jogler, G. Jóhannesson, T. Kamae, M. Kuss, G. La Mura, L. Latronico, F. Longo, F. Loparco, P. Lubrano, S. Maldera, D. Malyshev, A. Manfreda, M. N. Mazziotta, P. F. Michelson, N. Mirabal, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. E. Monzani, A. Morselli, I. V. Moskalenko, M. Negro, E. Nuss, E. Orlando, D. Paneque, J. S. Perkins, M. Pesce-Rollins, F. Piron, G. Pivato, T. A. Porter, G. Principe, S. Rainò, R. Rando, M. Razzano, A. Reimer, O. Reimer, C. Sgrò, D. Simone, E. J. Siskind, F. Spada, G. Spandre, P. Spinelli, H. Tajima, J. B. Thayer, L. Tibaldo, D. F. Torres, E. Troja, M. Wood, A. Worley, G. Zaharijas, and S. Zimmer
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- 2017
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46. Search for Cosmic-Ray Electron and Positron Anisotropies with Seven Years of Fermi Large Area Telescope Data
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S. Abdollahi, M. Ackermann, M. Ajello, A. Albert, W. B. Atwood, L. Baldini, G. Barbiellini, R. Bellazzini, E. Bissaldi, E. D. Bloom, R. Bonino, E. Bottacini, T. J. Brandt, P. Bruel, S. Buson, M. Caragiulo, E. Cavazzuti, A. Chekhtman, S. Ciprini, F. Costanza, A. Cuoco, S. Cutini, F. D’Ammando, F. de Palma, R. Desiante, S. W. Digel, N. Di Lalla, M. Di Mauro, L. Di Venere, B. Donaggio, P. S. Drell, C. Favuzzi, W. B. Focke, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Giglietto, F. Giordano, M. Giroletti, D. Green, S. Guiriec, A. K. Harding, T. Jogler, G. Jóhannesson, T. Kamae, M. Kuss, S. Larsson, L. Latronico, J. Li, F. Longo, F. Loparco, P. Lubrano, J. D. Magill, D. Malyshev, A. Manfreda, M. N. Mazziotta, M. Meehan, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. E. Monzani, A. Morselli, M. Negro, E. Nuss, T. Ohsugi, N. Omodei, D. Paneque, J. S. Perkins, M. Pesce-Rollins, F. Piron, G. Pivato, G. Principe, S. Rainò, R. Rando, M. Razzano, A. Reimer, O. Reimer, C. Sgrò, D. Simone, E. J. Siskind, F. Spada, G. Spandre, P. Spinelli, A. W. Strong, H. Tajima, J. B. Thayer, D. F. Torres, E. Troja, J. Vandenbroucke, G. Zaharijas, and S. Zimmer
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- 2017
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47. A descriptive analysis of an outbreak of measles and a multilevel mixed-effects analysis of factors associated with case isolation in healthcare settings, London (February–June 2016)
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Neville Q. Verlander, Rebecca Cordery, M. Meltzer, L. Begum, S. Rana, A. Bell, Yimmy Chow, Sooria Balasegaram, C. Heffernan, A. Wright, R. Mohammed-Klein, S. Perkins, and Maria Saavedra-Campos
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Adult ,Male ,medicine.medical_specialty ,Infectious Disease Transmission, Patient-to-Professional ,Adolescent ,Isolation (health care) ,Measles Vaccine ,Measles ,Occupational safety and health ,Disease Outbreaks ,Cohort Studies ,Patient Isolation ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,London ,Epidemiology ,Humans ,Infection control ,Medicine ,030212 general & internal medicine ,Child ,Infection Control ,business.industry ,030503 health policy & services ,Public health ,Public Health, Environmental and Occupational Health ,Infant ,General Medicine ,medicine.disease ,Triage ,Child, Preschool ,Family medicine ,Multilevel Analysis ,Female ,Health Facilities ,Factor Analysis, Statistical ,0305 other medical science ,business ,Cohort study - Abstract
Objectives We described the epidemiology and healthcare exposures during a measles outbreak in London and identified factors associated with isolation on arrival to healthcare premises. Study design We conducted a cohort study including all confirmed measles cases in London residents from February 1, 2016, to June 30, 2016, and semistructured interviews with two infection prevention and control teams (IPCTs). Methods We described the outbreak and conducted a multilevel mixed-effects analysis to assess the relationship between sociodemographic and clinical factors and isolation on arrival to healthcare premises. We summarised the interviews. Results There were 182 cases, mostly aged 17–35 years (46%; 84). Excluding cases younger than one year, 76% (92/120) were unvaccinated, including two healthcare workers. The majority presented with rash (97%; 174), and 42% (70/166) required hospitalisation. Of the recorded cases, 93% of cases (164/178) had visited a healthcare setting during their infectious period (median number of visits = 2). In 33% (59/178) of the visits, the case was isolated on arrival; when not isolated, four healthcare exposures resulted in further transmission. Presenting to the hospital as opposed to a general practitioner (GP) was associated with higher odds of isolation (odds ratio = 2.23, 95% confidence interval = 1.1–4.4) when adjusted for age, gender and presenting with a cough. The IPCT identified measles training using standardised risk assessments by triage nurses in accident and emergency and intelligence regarding measles activity in the community as positive measures to prevent healthcare exposures. Conclusions We recommend opportunistic immunisation of unvaccinated young adults by GPs and that occupational health departments ensure their staff are protected against measles. Raising measles awareness in healthcare settings via training or regular sharing of current measles surveillance activity from public health to the IPCT and GP may improve triage and isolation of cases on arrival to healthcare premises.
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- 2020
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48. Reticular Growth of Graphene Nanoribbon 2D Covalent Organic Frameworks
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Cameron Rogers, Gregory Veber, Juan Pablo Llinas, Wade S. Perkins, Alexander Liebman-Peláez, Felix R. Fischer, Jim Ciston, Christian S. Diercks, Jeffrey Bokor, Chenhui Zhu, and Kyunghoon Lee
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Materials science ,Graphene ,General Chemical Engineering ,Bilayer ,Biochemistry (medical) ,Nanotechnology ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Exfoliation joint ,0104 chemical sciences ,law.invention ,Crystal ,Chemical bond ,Covalent bond ,law ,Materials Chemistry ,Environmental Chemistry ,0210 nano-technology ,Graphene nanoribbons ,Macromolecule - Abstract
Summary The reticular synthesis of covalent organic frameworks (COFs), extended porous two-dimensional (2D) or three-dimensional (3D) networks held together by strong, highly directional chemical bonds, has thus far been restricted to small, shape-persistent, molecular building blocks. Here, we demonstrate the growth of crystalline 2D COFs from a polydisperse macromolecule derived from single-layer graphene, bottom-up synthesized quasi-one-dimensional (1D) graphene nanoribbons (GNRs). X-ray scattering and transmission electron microscopy reveal that 2D sheets of GNR-COFs self-assembled at a liquid-liquid interface stack parallel to the layer boundary and exhibit an orthotropic crystal packing. Liquid-phase exfoliation of multilayer GNR-COF crystals gives access to large-area (>105 nm2) bilayer and trilayer cGNR-COF films. The functional integration of extended 1D materials into crystalline COFs greatly expands the structural complexity and the scope of mechanical and physical materials properties accessible through a deterministic reticular bottom-up approach.
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- 2020
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49. Live-animal imaging of native hematopoietic stem and progenitor cells
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Sergei A. Vinogradov, Negar Seyedhassantehrani, Archibald S. Perkins, Tatiana V. Esipova, Azucena Ramos, Guoji Guo, Charles P. Lin, Raffaele A. Calogero, Joel A. Spencer, Riccardo Panero, Constantina Christodoulou, Stuart H. Orkin, Sarah Rudzinskas, Raphaël Turcotte, Shu-Chi A. Yeh, Timm Schroeder, Konstantinos D. Kokkaliaris, Yi Zhang, and Fernando D. Camargo
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0301 basic medicine ,Endosteum ,Multidisciplinary ,Motility ,hemic and immune systems ,single-cell sequencing ,Biology ,Article ,Bone remodeling ,Cell biology ,Transplantation ,03 medical and health sciences ,Haematopoiesis ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,medicine ,Bone marrow ,Stem cell ,Progenitor cell - Abstract
The biology of hematopoietic stem cells (HSCs) has predominantly been studied under transplantation conditions1,2. Particularly challenging has been the study of dynamic HSC behaviors given that live animal HSC visualization in the native niche still represents an elusive goal in the field. Here, we describe a dual genetic strategy in mice that restricts reporter labeling to a subset of the most quiescent long-term HSCs (LT-HSCs) and that is compatible with current intravital imaging approaches in the calvarial bone marrow (BM)3–5. We find that this subset of LT-HSCs resides in close proximity to both sinusoidal blood vessels and the endosteal surface. In contrast, multipotent progenitor cells (MPPs) display a broader distance distribution from the endosteum and are more likely to be associated with transition zone vessels. LT-HSCs are not found in BM niches with the deepest hypoxia and instead are found in similar hypoxic environments as MPPs. In vivo time-lapse imaging reveals that LT-HSCs display limited motility at steady-state. Following activation, LT-HSCs display heterogenous responses, with some cells becoming highly motile and a fraction of HSCs expanding clonally within spatially restricted domains. These domains have defined characteristics, as HSC expansion is found almost exclusively in a subset of BM cavities exhibiting bone-remodeling activities. In contrast, cavities with low bone-resorbing activities do not harbor expanding HSCs. These findings point to a new degree of heterogeneity within the BM microenvironment, imposed by the stages of bone turnover. Overall, our approach enables direct visualization of HSC behaviors and dissection of heterogeneity in HSC niches.
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- 2020
50. Investigating the Nature of Late-Time High-Energy GRB Emission Through Joint
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M, Ajello, L, Baldini, G, Barbiellini, D, Bastieri, R, Bellazzini, E, Bissaldi, R D, Blandford, R, Bonino, E, Bottacini, J, Bregeon, P, Bruel, R, Buehler, R A, Cameron, R, Caputo, P A, Caraveo, G, Chiaro, S, Ciprini, J, Cohen-Tanugi, D, Costantin, F, D'Ammando, F, DE Palma, N, DI Lalla, M, DI Mauro, L, DI Venere, A, Domínguez, C, Favuzzi, A, Franckowiak, Y, Fukazawa, S, Funk, P, Fusco, F, Gargano, D, Gasparrini, N, Giglietto, F, Giordano, M, Giroletti, D, Green, I A, Grenier, S, Guiriec, C, Holt, D, Horan, G, Jóhannesson, D, Kocevski, M, Kuss, G, LA Mura, S, Larsson, J, Li, F, Longo, F, Loparco, P, Lubrano, J D, Magill, S, Maldera, A, Manfreda, M N, Mazziotta, P F, Michelson, T, Mizuno, M E, Monzani, A, Morselli, M, Negro, E, Nuss, N, Omodei, M, Orienti, E, Orlando, V S, Paliya, J S, Perkins, M, Persic, M, Pesce-Rollins, F, Piron, G, Principe, J L, Racusin, S, Rainò, R, Rando, M, Razzano, S, Razzaque, A, Reimer, O, Reimer, C, Sgrò, E J, Siskind, G, Spandre, P, Spinelli, D, Tak, J B, Thayer, D F, Torres, G, Tosti, J, Valverde, M, Vogel, and K, Wood
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Astrophysics::High Energy Astrophysical Phenomena ,Article - Abstract
We use joint observations by the Neil Gehrels Swift X-ray Telescope (XRT) and the Fermi Large Area Telescope (LAT) of gamma-ray burst (GRB) afterglows to investigate the nature of the long-lived high-energy emission observed by Fermi LAT. Joint broadband spectral modeling of XRT and LAT data reveal that LAT non-detections of bright X-ray afterglows are consistent with a cooling break in the inferred electron synchrotron spectrum below the LAT and/or XRT energy ranges. Such a break is sufficient to suppress the high-energy emission so as to be below the LAT detection threshold. By contrast, LAT-detected bursts are best fit by a synchrotron spectrum with a cooling break that lies either between or above the XRT and LAT energy ranges. We speculate that the primary difference between GRBs with LAT afterglow detections and the non-detected population may be in the type of circumstellar environment in which these bursts occur, with late-time LAT detections preferentially selecting GRBs that occur in low wind-like circumburst density profiles. Furthermore, we find no evidence of high-energy emission in the LAT-detected population significantly in excess of the flux expected from the electron synchrotron spectrum fit to the observed X-ray emission. The lack of excess emission at high energies could be due to a shocked external medium in which the energy density in the magnetic field is stronger than or comparable to that of the relativistic electrons behind the shock, precluding the production of a dominant synchrotron self-Compton (SSC) component in the LAT energy range. Alternatively, the peak of the SSC emission could be beyond the 0.1–100 GeV energy range considered for this analysis.
- Published
- 2022
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