72 research outputs found

    Light Curves and Period Changes of Type II Cepheids in the Globular Clusters M3 and M5

    Full text link
    Light curves in the B, V, and I_c passbands have been obtained for the type II Cepheids V154 in M3 and V42 and V84 in M5. Alternating cycle behavior, similar to that seen among RV Tauri variables, is confirmed for V84. Old and new observations, spanning more than a century, show that V154 has increased in period while V42 has decreased in period. V84, on the other hand, has shown large, erratic changes in period that do not appear to reflect the long term evolution of V84 through the HR diagram.Comment: 28 pages, 12 figure

    The Lantern Vol. 62, No. 1, December 1994

    Get PDF
    • Hollow • A Little Knowledge is Dangerous • My Old Block • Life • The Natural Born Fool • Oracle • Formation of a Triangle • Marie on the Beach • The Tweed Derby • Tripping • In Vitro • The Character • Coming Home for Christmas • Unkempt • Too Much • Reimertanti-Ode • Seeds • Secrethttps://digitalcommons.ursinus.edu/lantern/1145/thumbnail.jp

    Host Galaxies of z=4 Quasars

    Full text link
    We have undertaken a project to investigate the host galaxies and environments of a sample of quasars at z~4. In this paper, we describe deep near-infrared imaging of 34 targets using the Magellan I and Gemini North telescopes. We discuss in detail special challenges of distortion and nonlinearity that must be addressed when performing PSF subtraction with data from these telescopes and their IR cameras, especially in very good seeing. We derive black hole masses from emission-line spectroscopy, and we calculate accretion rates from our K_s-band photometry, which directly samples the rest-frame B for these objects. We introduce a new isophotal diameter technique for estimating host galaxy luminosities. We report the detection of four host galaxies on our deepest, sharpest images, and present upper limits for the others. We find that if host galaxies passively evolve such that they brighten by 2 magnitudes or more in the rest-frame B band between the present and z=4, then high-z hosts are less massive at a given black hole mass than are their low-z counterparts. We argue that the most massive hosts plateau at <~10L*. We estimate the importance of selection effects on this survey and the subsequent limitations of our conclusions. These results are in broad agreement with recent semi-analytical models for the formation of luminous quasars and their host spheroids by mergers of gas-rich galaxies, with significant dissipation, and self-regulation of black hole growth and star-formation by the burst of merger-induced quasar activity.Comment: 61 pages including 18 figures, to appear in 2009 Oct 15 Ap

    Effect of a MUC5AC Antibody (NPC-1C) Administered With Second-Line Gemcitabine and Nab-Paclitaxel on the Survival of Patients With Advanced Pancreatic Ductal Adenocarcinoma: A Randomized Clinical Trial

    Get PDF
    Importance: Treatment options are limited for patients with advanced pancreatic ductal adenocarcinoma (PDAC) beyond first-line 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX), with such individuals commonly being treated with gemcitabine and nab-paclitaxel. Objective: To determine whether NPC-1C, an antibody directed against MUC5AC, might increase the efficacy of second-line gemcitabine and nab-paclitaxel in patients with advanced PDAC. Design, setting, and participants: This multicenter, randomized phase II clinical trial enrolled patients with advanced PDAC between April 2014 and March 2017 whose disease had progressed on first-line FOLFIRINOX. Eligible patients had tumors with at least 20 MUC5AC staining by centralized immunohistochemistry review. Statistical analysis was performed from April to May 2022. Interventions: Patients were randomly assigned to receive gemcitabine (1000 mg/m2) and nab-paclitaxel (125 mg/m2) administered intravenously on days 1, 8, and 15 of every 4-week cycle, with or without intravenous NPC-1C 1.5 mg/kg every 2 weeks. Main outcomes and measures: The primary end point was overall survival (OS). Secondary end points were progression-free survival (PFS), objective response rate (ORR), and safety. Pretreatment clinical variables were explored with Cox proportional hazards analysis. Results: A total of 78 patients (median [range] age, 62 [36-78] years; 32 [41%] women; 9 [12%] Black; 66 [85%] White) received second-line treatment with gemcitabine plus nab-paclitaxel (n = 40) or gemcitabine plus nab-paclitaxel and NPC-1C (n = 38). Median OS was 6.6 months (95% CI, 4.7-8.4 months) with gemcitabine plus nab-paclitaxel vs 5.0 months (95% CI, 3.3-6.5 months; P = .22) with gemcitabine plus nab-paclitaxel and NPC-1C. Median PFS was 2.7 months (95% CI, 1.9-4.1 months) with gemcitabine plus nab-paclitaxel vs 3.4 months (95% CI, 1.9-5.3 months; P = .80) with gemcitabine plus nab-paclitaxel and NPC-1C. The ORR was 3.1% (95% CI, 0.4%-19.7%) in the gemcitabine plus nab-paclitaxel and NPC-1C group and 2.9% (95% CI, 0.4%-18.7%) in the gemcitabine plus nab-paclitaxel group. No differences in toxicity were observed between groups, except that grade 3 or greater anemia occurred more frequently in patients treated with gemcitabine plus nab-paclitaxel and NPC-1C than gemcitabine plus nab-paclitaxel (39% [15 of 38] vs 10% [4 of 40]; P = .003). The frequency of chemotherapy dose reductions was similar in both groups (65% vs 74%; P = .47). Lower performance status, hypoalbuminemia, PDAC diagnosis less than or equal to 18 months before trial enrollment, lymphocyte-to-monocyte ratio less than 2.8, and CA19-9 greater than 2000 IU/mL were independently associated with poorer survival. Conclusions and relevance: In this randomized clinical trial of advanced PDAC, NPC-1C did not enhance the efficacy of gemcitabine/nab-paclitaxel. These data provide a benchmark for future trials investigating second-line treatment of PDAC. Trial registration: ClinicalTrials.gov Identifier: NCT01834235

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

    Get PDF
    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

    Get PDF
    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    James Prosek: An Un-Natural History

    Get PDF
    Scott Lacy is a contributing author, Un-Natural History and Transcendental Funk: The Artful Biology of James Prosek. Book description: Fully illustrated catalog for the James Prosek: Un-Natural History exhibition at Fairfield University\u27s Bellarmine Museum of Art (October 21-December, 2011), Fairfield, CT. Includes essays by three Fairfield University faculty members: Jill Deupi (Director, Bellarmine Museum of Art and Assistant Professor of Art History), Brian Walker (Associate Professor of Biology), and Scott Lacy (Assistant Professor of Anthropology). Seventeen full-color plates of works included in the exhibition as well as installation shots of the show.https://digitalcommons.fairfield.edu/sociologyandanthropology-books/1014/thumbnail.jp

    A Single Institution's Experience with Bevacizumab in Combination with Cytotoxic Chemotherapy in Progressive Malignant Glioma

    No full text
    Background Bevacizumab and irinotecan may represent one of the most active treatments in progressive malignant glioma. Limited published experience with bevacizumab in patients with CNS tumors raises concerns regarding toxicity, particularly in regards to hemorrhage and thromboembolism. Methods We retrospectively reviewed 36 patients with progressive malignant glioma after prior resection, chemotherapy and radiation who were treated with bevacizumab at our institution. Patients were evaluated for bevacizumab-related adverse events, time to treatment failure (TTF) and overall survival (OS). Two patients who progressed or died prior to completion of 4 cycles of therapy were analyzed for adverse events only. Results Patients were treated with bevacizumab alone (1), bevacizumab plus irinotecan (31), or bevacizumab plus carboplatin (4). In 34 patients who received >4 cycles of bevacizumab, median TTF and OS were 16 and 32 weeks, respectively. Toxicities included 1 arterial thrombosis, 4 venous thromboses, and 3 clinically significant CNS hemorrhages. Conclusion Overall, our results confirm the efficacy and safety of bevacizumab in combination with chemotherapy in patients with progressive malignant glioma. Although the TTF and OS were less than previously reported with the combination of bevacizumab and irinotecan, this was an unselected patient population with 50% of patients having received >1 prior chemotherapy regimen

    Pseudocirrhosis in a pancreatic cancer patient with liver metastases: A case report of complete resolution of pseudocirrhosis with an early recognition and management

    No full text
    We report a case of pseudocirrhosis arising in the setting of regression of liver metastases from pancreatic cancer. A 55-year-old asymptomatic woman presented to our clinic with newly diagnosed metastatic pancreatic cancer with extensive liver metastases. She underwent systemic chemotherapy with gemcitabine and oxaliplatin (GEMOX). After 8 cycles of therapy, she had a remarkable response to the therapy evidenced by decline of carcinoembryonic antigen (CEA) and CA19 by > 50% and nearly complete resolution of hepatic metastases in computed tomography (CT) scan. Shortly after, she developed increasing bilateral ankle edema and ascites, associated with dyspnea, progressive weight gain, and declining performance status. Gemcitabine and oxaliplatin were discontinued as other causes of her symptoms such as congestive heart disease or venous thrombosis were ruled out. CT scan 6 mo after the initiation of GEMOX revealed worsening ascites with a stable pancreatic mass. However, it also revealed a lobular hepatic contour, segmental atrophy, and capsular retraction mimicking the appearance of cirrhosis. She was managed with aggressive diuresis and albumin infusions which eventually resulted in a resolution of the above-mentioned symptoms as well as complete resolution of pseudocirrhotic appearance of the liver and ascites in CT scan. This case demonstrates that pancreatic cancer patients can develop pseudocirrhosis. Clinicians and radiologist should be well aware of this entity as early recognition and management can lead to a near complete recovery of liver function and much improved quality of life as illustrated in this case
    corecore