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Characteristics of healthcare personnel with SARS-CoV-2 infection: 10 emerging infections program sites in the United States, April 2020–December 2021
- Nora Chea, Taniece Eure, Rebecca Alkis Ramirez, Maria Zlotorzynska, Gregory T. Blazek, Joelle Nadle, Jane Lee, Christopher A. Czaja, Helen Johnston, Devra Barter, Melissa Kellogg, Catherine Emanuel, James Meek, Monica Brackney, Stacy Carswell, Stepy Thomas, Scott K. Fridkin, Lucy E. Wilson, Rebecca Perlmutter, Kaytlynn Marceaux-Galli, Ashley Fell, Sara Lovett, Sarah Lim, Ruth Lynfield, Sarah Shrum Davis, Erin C. Phipps, Marla Sievers, Ghinwa Dumyati, Christopher Myers, Christine Hurley, Erin Licherdell, Rebecca Pierce, Valerie L. S. Ocampo, Eric W. Hall, Christopher Wilson, Cullen Adre, Erika Kirtz, Tiffanie M. Markus, Kathryn Billings, Ian D Plumb, Glen R. Abedi, Jade James-Gist, Shelley S. Magill, Cheri T. Grigg
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- Journal:
- Infection Control & Hospital Epidemiology , First View
- Published online by Cambridge University Press:
- 21 May 2024, pp. 1-9
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Background:
Understanding characteristics of healthcare personnel (HCP) with SARS-CoV-2 infection supports the development and prioritization of interventions to protect this important workforce. We report detailed characteristics of HCP who tested positive for SARS-CoV-2 from April 20, 2020 through December 31, 2021.
Methods:CDC collaborated with Emerging Infections Program sites in 10 states to interview HCP with SARS-CoV-2 infection (case-HCP) about their demographics, underlying medical conditions, healthcare roles, exposures, personal protective equipment (PPE) use, and COVID-19 vaccination status. We grouped case-HCP by healthcare role. To describe residential social vulnerability, we merged geocoded HCP residential addresses with CDC/ATSDR Social Vulnerability Index (SVI) values at the census tract level. We defined highest and lowest SVI quartiles as high and low social vulnerability, respectively.
Results:Our analysis included 7,531 case-HCP. Most case-HCP with roles as certified nursing assistant (CNA) (444, 61.3%), medical assistant (252, 65.3%), or home healthcare worker (HHW) (225, 59.5%) reported their race and ethnicity as either non-Hispanic Black or Hispanic. More than one third of HHWs (166, 45.2%), CNAs (283, 41.7%), and medical assistants (138, 37.9%) reported a residential address in the high social vulnerability category. The proportion of case-HCP who reported using recommended PPE at all times when caring for patients with COVID-19 was lowest among HHWs compared with other roles.
Conclusions:To mitigate SARS-CoV-2 infection risk in healthcare settings, infection prevention, and control interventions should be specific to HCP roles and educational backgrounds. Additional interventions are needed to address high social vulnerability among HHWs, CNAs, and medical assistants.
Practices and activities among healthcare personnel with severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection working in different healthcare settings—ten Emerging Infections Program sites, April–November 2020
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- Nora Chea, Taniece Eure, Austin R. Penna, Cedric J. Brown, Joelle Nadle, Deborah Godine, Linda Frank, Christopher A. Czaja, Helen Johnston, Devra Barter, Betsy Feighner Miller, Katie Angell, Kristen Marshall, James Meek, Monica Brackney, Stacy Carswell, Stepy Thomas, Lucy E. Wilson, Rebecca Perlmutter, Kaytlynn Marceaux-Galli, Ashley Fell, Sarah Lim, Ruth Lynfield, Sarah Shrum Davis, Erin C. Phipps, Marla Sievers, Ghinwa Dumyati, Cathleen Concannon, Kathryn McCullough, Amy Woods, Sandhya Seshadri, Christopher Myers, Rebecca Pierce, Valerie L. S. Ocampo, Judith A. Guzman-Cottrill, Gabriela Escutia, Monika Samper, Sandra A. Pena, Cullen Adre, Matthew Groenewold, Nicola D. Thompson, Shelley S. Magill
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 43 / Issue 8 / August 2022
- Published online by Cambridge University Press:
- 02 June 2021, pp. 1058-1062
- Print publication:
- August 2022
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Healthcare personnel with severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection were interviewed to describe activities and practices in and outside the workplace. Among 2,625 healthcare personnel, workplace-related factors that may increase infection risk were more common among nursing-home personnel than hospital personnel, whereas selected factors outside the workplace were more common among hospital personnel.
Methods for training collaborative biostatisticians
- Gina-Maria Pomann, L. Ebony Boulware, Shari Messinger Cayetano, Manisha Desai, Felicity T. Enders, John A. Gallis, Jonathan Gelfond, Steven C. Grambow, Alexandra L. Hanlon, Angelean Hendrix, Pandurang Kulkarni, Jodi Lapidus, Hui-Jie Lee, Jonathan D. Mahnken, Julie P. McKeel, Rebecca Moen, Robert A. Oster, Sarah Peskoe, Greg Samsa, Thomas G. Stewart, Tracy Truong, Lisa Wruck, Samantha M. Thomas
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- Journal:
- Journal of Clinical and Translational Science / Volume 5 / Issue 1 / 2021
- Published online by Cambridge University Press:
- 04 August 2020, e26
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The emphasis on team science in clinical and translational research increases the importance of collaborative biostatisticians (CBs) in healthcare. Adequate training and development of CBs ensure appropriate conduct of robust and meaningful research and, therefore, should be considered as a high-priority focus for biostatistics groups. Comprehensive training enhances clinical and translational research by facilitating more productive and efficient collaborations. While many graduate programs in Biostatistics and Epidemiology include training in research collaboration, it is often limited in scope and duration. Therefore, additional training is often required once a CB is hired into a full-time position. This article presents a comprehensive CB training strategy that can be adapted to any collaborative biostatistics group. This strategy follows a roadmap of the biostatistics collaboration process, which is also presented. A TIE approach (Teach the necessary skills, monitor the Implementation of these skills, and Evaluate the proficiency of these skills) was developed to support the adoption of key principles. The training strategy also incorporates a “train the trainer” approach to enable CBs who have successfully completed training to train new staff or faculty.
Cardiovascular risk factors, anxiety symptoms and inflammation markers: Evidence of association from a cross-sectional study
- G. Rioli, S. Tassi, G. Mattei, S. Alboni, S. Mancini, C. Artoni, M. Galletti, N. Giambalvo, G. Galli, M. Marchi, A. Minarini, G. Montardi, D. Perrone, G. Pollutri, L. Roncucci, S. Saraceni, G. Spiga, C. Visentini, G.M. Galeazzi, S. Ferrari
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- European Psychiatry / Volume 41 / Issue S1 / April 2017
- Published online by Cambridge University Press:
- 23 March 2020, p. s503
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Introduction
Anxiety disorders and Cardiovascular (CV) diseases, among the most common disorders in Western World, are often comorbid. A chronic systemic inflammatory state might be a shared underlining pathophysiological mechanism.
AimsTo investigate the association between anxiety symptoms, CV risks factors and inflammatory markers in an outpatient sample.
MethodsCross-sectional study. Inclusion criteria: outpatients aged ≥40 years, attending colonoscopy after positive faecal occult blood test, negative medical history for cancer. Collected data: blood pressure, glycaemia, lipid profile, waist circumference, BMI, PCR (C Reactive Protein), LPS (bacterial Lipopolysaccharide). Psychometric tests: HADS, TCI, IMSA, SF36. Statistical analysis performed with STATA13.
ResultsFifty four patients enrolled (27 males, 27 females). Sixteen patients (30.19%) were positive for anxiety symptoms. Thirty-three patients (61.11%) had hypertension, 14 (25.93%) hyperglycaemia and 64.81% were overweight, with frank obesity (BMI≥ 30) in 11 subjects (20.37%). Anxiety symptoms were associated with low hematic HDL values (OR = 0.01; P = 0.01) and high concentration of triglycerides (OR = 0.023; P = 0.02) at the multiple regression model. At the univariate logistic analysis, anxiety was associated with LPS (OR = 1.06; P = 0.04).
ConclusionsFurther evidence over the epidemiological link between common mental disorders and CV diseases was collected, with possible hints on pathophysiology and causative mechanisms related to inflammation. The importance of screening for anxiety and depression in medical populations is confirmed. Suggestions on future availability of screening tools based on inflammatory-related indicators should be the focus of future research.
Disclosure of interestThe authors have not supplied their declaration of competing interest.
Prevalence of metabolic syndrome and of symptoms of anxiety and depression in patients undergoing colonoscopy
- M. Marchi, S. Alboni, A. Fabbrizi, L. Feltri, G. Galli, A. Guicciardi, S. Mancini, G. Mattei, A. Minarini, D. Perrone, G. Rioli, L. Roncucci, P. Sena, S. Ferrari
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- European Psychiatry / Volume 41 / Issue S1 / April 2017
- Published online by Cambridge University Press:
- 23 March 2020, pp. S318-S319
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Introduction
Metabolic syndrome (MetS) is defined by metabolic and cardio-vascular impairments and is frequently associated with anxiety and depressive disorders. Both MetS and anxiety-depressive syndromes feature similar systemic inflammatory alterations. Inflammation of the large bowel is also a key factor for the development of colorectal cancer (CRC).
ObjectiveTo measure the prevalence of MetS and symptoms of anxiety and depression among patients undergoing colonoscopy.
MethodsCross-sectional study. Patients undergoing colonoscopy aged 40 or more, with negative history for neoplasia or inflammatory bowel disease, were enrolled. Data collected: colonoscopy outcome, presence/absence of MetS (IDF and ATP III criteria), presence/absence of depressive and anxiety symptoms assessed with HADS.
ResultsThe sample was made up of 53 patients (female 24, 45.3%). Mean age was 60.66 ± 9.08. At least one adenoma was found to 23 patients (43.3%). Prevalence of MetS ranged from 34% to 36% (ATP III and IDF criteria, respectively). Prevalence of depressive and anxiety symptoms was 20% and 33%, respectively.
ConclusionPrevalence of MetS, anxiety and depressive symptoms among patients undergoing colonoscopy was higher than in the general population.
Disclosure of interestThe authors have not supplied their declaration of competing interest.
An Italian observational study on subclinical cardiovascular risk factors and depressive symptomatology. A suggestion for the potential utility of a sinergic cardio-psychiatric perspective
- S. Tassi, G. Rioli, G. Mattei, S. Mancini, S. Alboni, L. Roncucci, P. Sena, F. Mariani, M. Marchi, A. Fabbrizi, L. Feltri, C. Visentini, G. Pollutri, C. Artoni, S. Saraceni, G. Galli, G. Spiga, A. Minarini, D. Perrone, M. Galletti, N. Giambalvo, G. Montardi, G.M. Galeazzi, S. Ferrari, PNEI-MO Research Group
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- European Psychiatry / Volume 41 / Issue S1 / April 2017
- Published online by Cambridge University Press:
- 23 March 2020, p. S318
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Introduction
Growing evidence has been collected over the complex, intertwined pathophysiological connection among subclinical cardiovascular (CV) disease, i.e. atherosclerosis, systemic low pro-inflammatory states and psychiatric disorders/symptomatology (anxiety, depression), with controversial results.
AimAim of this study was to investigate the possible link between subclinical CV risk factors (atherosclerosis), depressive symptoms, and inflammation.
MethodsCross-sectional study. Inclusion criteria: outpatients aged ≥40 years, attending colonoscopy after positive faecal occult blood test, negative medical history for cancer. Collected data: blood pressure, glycaemia, lipid profile, waist circumference, BMI, PCR (C reactive protein), LPS (bacterial lipopolysaccharide), ultrasound carotid intima-media thickness (c-IMT). Psychometric tests: HADS, TCI, IMSA, SF36. Statistical analysis performed with STATA13.
ResultsThe 54 patients enrolled were equally distributed by gender. CV risk factors were common in the study population, with 33 patients (61.11%) with hypertension, 14 (25.93%) with hyperglycaemia, 20 (37.4%) with hypertriglyceridemia, 19 (35.19%) with low HDL and 64.81% with overweight. High levels of PCR were found in 24 subjects (44.44%). Right c-IMT was increased in 26.41% of the sample, and 11.32% had an atheromatous plaque. Left c-IMT was increased in 24.53% of patients, with a plaque in 7.55% of them. Clinically relevant depressive symptoms were found in the 18.87% of the sample and were statistically significantly associated with PCR (OR = 28.63; P = 0.01).
ConclusionsEvidence contributing to the so-called “inflammation theory” of depression and supporting the association between mood and CV disorders was here collected, supporting the need for a multidisciplinary approach to the diagnosis and treatment of such conditions, assuming a clinically-translated PNEI (psycho-neuro-endocrino-immunological) perspective.
Disclosure of interestThe authors have not supplied their declaration of competing interest.
Recommended nomenclature for zeolite minerals: report of the subcommittee on zeolites of the International Mineralogical Association, Commission on New Minerals and Mineral Names
- Douglas S. Coombs, Alberto Alberti, Thomas Armbruster, Gilberto Artioli, Carmine Colella, Ermanno Galli, Joel D. Grice, Friedrich Liebau, Joseph A. Mandarino, Hideo Minato, Ernest H. Nickel, Elio Passaglia, Donald R. Peacor, Simona Quartieri, Romano Rinaldi, Malcolm Ross, Richard A. Sheppard, Ekkehart Tillmanns, Giovanna Vezzalini
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- Mineralogical Magazine / Volume 62 / Issue 4 / August 1998
- Published online by Cambridge University Press:
- 05 July 2018, pp. 533-571
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This report embodies recommendations on zeolite nomenclature approved by the International Mineralogical Association Commission on New Minerals and Mineral Names. In a working definition of a zeolite mineral used for this review, interrupted tetrahedral framework structures are accepted where other zeolitic properties prevail, and complete substitution by elements other than Si and Al is allowed. Separate species are recognized in topologically distinctive compositional series in which different extra-framework cations are the most abundant in atomic proportions. To name these, the appropriate chemical symbol is attached by a hyphen to the series name as a suffix except for the names harmotome, pollucite and wairakite in the phillipsite and analcime series. Differences in spacegroup symmetry and in order—disorder relationships in zeolites having the same topologically distinctive framework do not in general provide adequate grounds for recognition of separate species. Zeolite species are not to be distinguished solely on Si : Al ratio except for heulandite (Si : Al < 4.0) and clinoptilolite (Si : Al ⩾ 4.0). Dehydration, partial hydration, and over-hydration are not sufficient grounds for the recognition of separate species of zeolites. Use of the term ‘ideal formula’ should be avoided in referring to a simplified or averaged formula of a zeolite.
Newly recognized species in compositional series are as follows: brewsterite-Sr, -Ba; chabazite-Ca, - Na, -K; clinoptilolite-K, -Na, -Ca; dachiardite-Ca, -Na; erionite-Na, -K, -Ca; faujasite-Na, -Ca, -Mg; ferrierite-Mg, -K, -Na; gmelinite-Na, -Ca, -K; heulandite-Ca, -Na, -K, -Sr; levyne-Ca, -Na; paulingite-K, -Ca; phillipsite-Na, -Ca, -K; stilbite-Ca, -Na.
Key references, type locality, origin of name, chemical data, IZA structure-type symbols, space-group symmetry, unit-cell dimensions, and comments on structure are listed for 13 compositional series, 82 accepted zeolite mineral species, and three of doubtful status. Herschelite, leonhardite, svetlozarite, and wellsite are discredited as mineral species names. Obsolete and discredited names are listed.
Monitoring and assessment of ingestive chewing sounds for prediction of herbage intake rate in grazing cattle
- J. R. Galli, C. A. Cangiano, M. A. Pece, M. J. Larripa, D. H. Milone, S. A. Utsumi, E. A. Laca
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Accurate measurement of herbage intake rate is critical to advance knowledge of the ecology of grazing ruminants. This experiment tested the integration of behavioral and acoustic measurements of chewing and biting to estimate herbage dry matter intake (DMI) in dairy cows offered micro-swards of contrasting plant structure. Micro-swards constructed with plastic pots were offered to three lactating Holstein cows (608±24.9 kg of BW) in individual grazing sessions (n=48). Treatments were a factorial combination of two forage species (alfalfa and fescue) and two plant heights (tall=25±3.8 cm and short=12±1.9 cm) and were offered on a gradient of increasing herbage mass (10 to 30 pots) and number of bites (~10 to 40 bites). During each grazing session, sounds of biting and chewing were recorded with a wireless microphone placed on the cows’ foreheads and a digital video camera to allow synchronized audio and video recordings. Dry matter intake rate was higher in tall alfalfa than in the other three treatments (32±1.6 v. 19±1.2 g/min). A high proportion of jaw movements in every grazing session (23 to 36%) were compound jaw movements (chew-bites) that appeared to be a key component of chewing and biting efficiency and of the ability of cows to regulate intake rate. Dry matter intake was accurately predicted based on easily observable behavioral and acoustic variables. Chewing sound energy measured as energy flux density (EFD) was linearly related to DMI, with 74% of EFD variation explained by DMI. Total chewing EFD, number of chew-bites and plant height (tall v. short) were the most important predictors of DMI. The best model explained 91% of the variation in DMI with a coefficient of variation of 17%. Ingestive sounds integrate valuable information to remotely monitor feeding behavior and predict DMI in grazing cows.
British Escherichia coli O157 in Cattle Study (BECS): to determine the prevalence of E. coli O157 in herds with cattle destined for the food chain
- M. K. HENRY, S. C. TONGUE, J. EVANS, C. WEBSTER, I. J. McKENDRICK, M. MORGAN, A. WILLETT, A. REEVES, R. W. HUMPHRY, D. L. GALLY, G. J. GUNN, M. E. CHASE-TOPPING
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- Journal:
- Epidemiology & Infection / Volume 145 / Issue 15 / November 2017
- Published online by Cambridge University Press:
- 19 September 2017, pp. 3168-3179
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Escherichia coli O157 are zoonotic bacteria for which cattle are an important reservoir. Prevalence estimates for E. coli O157 in British cattle for human consumption are over 10 years old. A new baseline is needed to inform current human health risk. The British E. coli O157 in Cattle Study (BECS) ran between September 2014 and November 2015 on 270 farms across Scotland and England & Wales. This is the first study to be conducted contemporaneously across Great Britain, thus enabling comparison between Scotland and England & Wales. Herd-level prevalence estimates for E. coli O157 did not differ significantly for Scotland (0·236, 95% CI 0·166–0·325) and England & Wales (0·213, 95% CI 0·156–0·283) (P = 0·65). The majority of isolates were verocytotoxin positive. A higher proportion of samples from Scotland were in the super-shedder category, though there was no difference between the surveys in the likelihood of a positive farm having at least one super-shedder sample. E. coli O157 continues to be common in British beef cattle, reaffirming public health policy that contact with cattle and their environments is a potential infection source.
Designing defect spins for wafer-scale quantum technologies
- William F. Koehl, Hosung Seo, Giulia Galli, David D. Awschalom
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- Journal:
- MRS Bulletin / Volume 40 / Issue 12 / December 2015
- Published online by Cambridge University Press:
- 27 November 2015, pp. 1146-1153
- Print publication:
- December 2015
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The past decade has seen remarkable progress in the development of the nitrogen-vacancy (NV) defect center in diamond, which is one of the leading candidates for quantum information technologies. The success of the NV center as a solid-state qubit has stimulated an active search for similar defect spins in other technologically important and mature semiconductors, such as silicon carbide. If successfully combined with the advanced microfabrication techniques available to such materials, coherent quantum control of defect spins could potentially lead to semiconductor-based, wafer-scale quantum technologies that make use of exotic quantum mechanical phenomena like entanglement. In this article, we describe the robust spin property of the NV center and the current status of NV center research for quantum information technologies. We then outline first-principles computational modeling techniques based on density functional theory to efficiently search for potential spin defects in nondiamond hosts suitable for quantum information applications. The combination of computational modeling and experimentation has proven invaluable in this area, and we describe the successful interplay between theory and experiment achieved with the divacancy spin qubit in silicon carbide.
Optical Detection of Radiocarbon Dioxide: First Results and AMS Intercomparison
- I Galli, S Bartalini, P Cancio, P De Natale, D Mazzotti, G Giusfredi, M E Fedi, P A Mandò
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- Radiocarbon / Volume 55 / Issue 2 / 2013
- Published online by Cambridge University Press:
- 09 February 2016, pp. 213-223
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- 2013
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The first results of an optical method for measuring radiocarbon concentrations, based on mid-infrared laser spectroscopy of a carbon dioxide gas sample, are presented with the theoretical bases explained in detail. The first measurements on modern and highly enriched samples show the extreme linearity of this technique over more than 5 decades. An intercomparison with accelerator mass spectrometry (AMS) is performed both for modern and 14C-dead samples, assessing the almost perfect agreement of their respectively measured concentration values. The main features of our technique are compared with liquid scintillation counting (LSC) and AMS, and future developments of the current setup are discussed.
Contributors
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- By Kumar Alagappan, Janet G. Alteveer, Kim Askew, Paul S. Auerbach, Katherine Bakes, Kip Benko, Paul D. Biddinger, Victoria Brazil, Anthony FT Brown, Andrew K. Chang, Alice Chiao, Wendy C. Coates, Jamie Collings, Gilbert Abou Dagher, Jonathan E. Davis, Peter DeBlieux, Alessandro Dellai, Emily Doelger, Pamela L. Dyne, Gino Farina, Robert Galli, Gus M. Garmel, Daniel Garza, Laleh Gharahbaghian, Gregory H. Gilbert, Michael A. Gisondi, Steven Go, Jeffrey M. Goodloe, Swaminatha V. Gurudevan, Micelle J. Haydel, Stephen R. Hayden, Corey R. Heitz, Gregory W. Hendey, Mel Herbert, Cherri Hobgood, Michelle Huston, Loretta Jackson-Williams, Anja K. Jaehne, Mary Beth Johnson, H. Brendan Kelleher, Peter G Kumasaka, Melissa J. Lamberson, Mary Lanctot-Herbert, Erik Laurin, Brian Lin, Michelle Lin, Douglas Lowery-North, Sharon E. Mace, S. V. Mahadevan, Thomas M. Mailhot, Diku Mandavia, David E. Manthey, Jorge A. Martinez, Amal Mattu, Lynne McCullough, Steve McLaughlin, Timothy Meyers, Gregory J. Moran, Randall T. Myers, Christopher R.H. Newton, Flavia Nobay, Robert L. Norris, Catherine Oliver, Jennifer A. Oman, Rita Oregon, Phillips Perera, Susan B. Promes, Emanuel P. Rivers, John S. Rose, Carolyn J. Sachs, Jairo I. Santanilla, Rawle A. Seupaul, Fred A. Severyn, Ghazala Q. Sharieff, Lee W. Shockley, Stefanie Simmons, Barry C. Simon, Shannon Sovndal, George Sternbach, Matthew Strehlow, Eustacia (Jo) Su, Stuart P. Swadron, Jeffrey A. Tabas, Sophie Terp, R. Jason Thurman, David A. Wald, Sarah R. Williams, Teresa S. Wu, Ken Zafren
- Edited by S. V. Mahadevan, Stanford University School of Medicine, California, Gus M. Garmel
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- An Introduction to Clinical Emergency Medicine
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- 05 May 2012
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- 10 April 2012, pp xi-xvi
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. 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Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. 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Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. 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Van Bavel, Steven Vanderputten, Peter Van der Veer, Huub Van de Sandt, Louis Van Tongeren, Luke A. Veronis, Noel Villalba, Ramón Vinke, Tim Vivian, David Voas, Elena Volkova, Katharina von Kellenbach, Elina Vuola, Timothy Wadkins, Elaine M. Wainwright, Randi Jones Walker, Dewey D. Wallace, Jerry Walls, Michael J. Walsh, Philip Walters, Janet Walton, Jonathan L. Walton, Wang Xiaochao, Patricia A. Ward, David Harrington Watt, Herold D. Weiss, Laurence L. Welborn, Sharon D. Welch, Timothy Wengert, Traci C. West, Merold Westphal, David Wetherell, Barbara Wheeler, Carolinne White, Jean-Paul Wiest, Frans Wijsen, Terry L. Wilder, Felix Wilfred, Rebecca Wilkin, Daniel H. Williams, D. Newell Williams, Michael A. Williams, Vincent L. Wimbush, Gabriele Winkler, Anders Winroth, Lauri Emílio Wirth, James A. Wiseman, Ebba Witt-Brattström, Teofil Wojciechowski, John Wolffe, Kenman L. Wong, Wong Wai Ching, Linda Woodhead, Wendy M. Wright, Rose Wu, Keith E. Yandell, Gale A. Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Beryllium abundances and the formation of the halo and the thick disk
- Rodolfo Smiljanic, L. Pasquini, P. Bonifacio, D. Galli, B. Barbuy, R. Gratton, S. Randich
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- Journal:
- Proceedings of the International Astronomical Union / Volume 5 / Issue S268 / November 2009
- Published online by Cambridge University Press:
- 23 April 2010, pp. 483-488
- Print publication:
- November 2009
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The single stable isotope of beryllium is a pure product of cosmic-ray spallation in the ISM. Assuming that the cosmic-rays are globally transported across the Galaxy, the beryllium production should be a widespread process and its abundance should be roughly homogeneous in the early-Galaxy at a given time. Thus, it could be useful as a tracer of time. In an investigation of the use of Be as a cosmochronometer and of its evolution in the Galaxy, we found evidence that in a log(Be/H) vs. [α/Fe] diagram the halo stars separate into two components. One is consistent with predictions of evolutionary models while the other is chemically indistinguishable from the thick-disk stars. This is interpreted as a difference in the star formation history of the two components and suggests that the local halo is not a single uniform population where a clear age-metallicity relation can be defined. We also found evidence that the star formation rate was lower in the outer regions of the thick disk, pointing towards an inside-out formation.
A view of the Galactic halo using beryllium as a time scale
- Rodolfo Smiljanic, L. Pasquini, P. Bonifacio, D. Galli, B. Barbuy, R. Gratton, S. Randich
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- Journal:
- Proceedings of the International Astronomical Union / Volume 5 / Issue S265 / August 2009
- Published online by Cambridge University Press:
- 09 March 2010, pp. 134-135
- Print publication:
- August 2009
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Beryllium stellar abundances were suggested to be a good tracer of time in the early Galaxy. In an investigation of its use as a cosmochronometer, using a large sample of local halo and thick-disk dwarfs, evidence was found that in a log(Be/H) vs. [α/Fe] diagram the halo stars separate into two components. One is consistent with predictions of evolutionary models while the other is chemically indistinguishable from the thick-disk stars. This is interpreted as a difference in the star formation history of the two components and suggests that the local halo is not a single uniform population where a clear age-metallicity relation can be defined.
Developmentally regulated markers of in vitro-produced preimplantation bovine embroys
- D. Shehu, G. Marsicano, J.-E. Fléchon, C. Galli
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Expression of various developmentally regulated markers was screened throughout the preimplantation stages of in vitro-derived bovine embryos. This was done by investigating the distribution of several nuclear, cytoplasmic and extracellular proteins by means of immunofluorescence microscopy. While lamin B appeared as a constitutive component of nuclei of all preimplantation stages, lamins A/C had a stage-related distribution. The early cleavage stage nuclei contained lamins A/C which generally disappeared in the following stages, with the possible exception of a few positive nuclei in the morula and early blastocyst stage. In the expanded blastocyst stage the nuclei of trophectoderm cells became positive while no positivity was observed in the inner cell mass cells. Starting from day 6, the appearance and/or polarised distribution of various cytoskeletal and cytoskeleton-related components such as Factin, α-catenin and E-cadherin gave an insight into the timing of events related to compaction of bovine e bryos. Compaction was correlated with the first differentiation event, i.e. the formation of trophectoderm; this is the first embryonic epithelium, characterised by cytokeratins and desmoplakin. Extracellular fibronectin was first detected in the early blastocyst stage shortly before the morphological differentiation of primitive endoderm, and in the later stages it was localised at the interface between trophectoderm and extraembryonic endoderm. Laminin and collagen IV were expressed by the endoderm cells and contributed to the extracellular matrix underlying the trophectoderm. This study is a first attempt to characterise the cells of in vitro-derived bovine embryos valid for cell line derivation.
Beryllium and the formation of the Thick Disk and of the Halo
- Luca Pasquini, R. Smiljanic, P. Bonifacio, R. Gratton, D. Galli, S. Randich
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- Journal:
- Proceedings of the International Astronomical Union / Volume 4 / Issue S254 / June 2008
- Published online by Cambridge University Press:
- 01 June 2008, pp. 203-208
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- June 2008
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We use Beryllium to investigate star formation in the early Galaxy. Be has been demonstrated to be a good indicator of time in these early epochs. By analyzing the so-far largest sample of halo and thick disk metal poor stars, we find a clear scatter in Be for a given value of [Fe/H] and [O/H]. The scatter is very pronounced for Halo stars, while it is marginal for thick disk stars. Our halo stars separate in the [α/Fe] - Be diagram, showing two main branches: one indistinguishable from the thick disk stars, and one with lower [α/Fe] ratio. The stars belonging to this branch are characterized by highly eccentric orbits and small perigalactic radius (Rmin). Their kinematics are consistent with an accreted component.
Optical Properties of Polystyrene Opals Infiltrated with Cyanine Dyes in the form of J-Aggregates
- F. Marabelli, D. Comoretto, D. Bajoni, M. Galli, L. Fornasari
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- MRS Online Proceedings Library Archive / Volume 846 / 2004
- Published online by Cambridge University Press:
- 01 February 2011, DD12.11
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- 2004
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We report preliminary data on the infiltration of polystyrene opals with cyanine dye water solutions, which are known to form J-aggregates. Different approaches are used to infiltrate cyanines inside opals. The degree of infiltration is evaluated by scanning and transmission electron microscopy as well as micro reflectance spectroscopy. Data show that in spite of the low wettability of polystyrene with water solutions, some infiltration can be achieved. Even though this degree of infiltration is still not enough to observe strong modification on the photonic band structures, further strategies to improve it are in progress.
Optical Spectroscopy of Silicon-On-Insulator Waveguide Photonic Crystals
- D. Bajoni, M. Galli, M. Belotti, F. Paleari, M. Patrini, G. Guizzetti, D. Gerace, M. Agio, L.C. Andreani, Y. Chen
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- Journal:
- MRS Online Proceedings Library Archive / Volume 817 / 2004
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- 15 March 2011, L2.8
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- 2004
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We report on a complete optical investigation on two-dimensional silicon-on-insulator (SOI) waveguide photonic crystals obtained by electron beam lithography and reactive ion etching. The dispersion of photonic modes is fully investigated both above and below the light-line by means of angle- and polarization-resolved micro-reflectance and attenuated total reflectance measurements.
The investigated samples consisted in a) large area (300 × 300 μm2) two-dimensional (2D) triangular lattices of air holes containing repeated line–defects; b) small area triangular lattices of holes with different number of periods and /or line defects integrated in a ridge type waveguide structure.
In the case of large area samples, variable-angle reflectance and ATR is measured from the sample surface in a wide spectral range from 0.2 to 2 eV both in TE and TM polarizations. The sharp resonances observed in the polarized reflectance and ATR spectra allow mapping of the photonic dispersion of both radiative and guided modes. Experimentally determined and compared to those calculated by means of an expansion on the basis of the waveguide modes.
In the case of ridge type waveguide-integrated photonic crystals, transmission is measured in the 0.9-1.7 eV spectral range by an edge-coupling technique. Transmission spectra exhibit significant attenuation corresponding to the photonic gaps along the Γ–M and Γ–K directions respectively, even when a small number of hole periods is integrated in the ridge waveguide. Good agreement is obtained by comparing the measured transmission spectra with the calculated photonic bands.
The Role of H2 Molecules in Primordial Star Formation
- from 4 - Extragalactic and Cosmology
- Edited by F. Combes, Observatoire de Paris, DEMIRM, G. Pineau des Forets, Observatoire de Paris de Meudon, DAEC
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- Molecular Hydrogen in Space
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- 04 August 2010
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- 06 November 2000, pp 247-258
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Summary
H2 and HD molecules provide the cooling needed for the fragmentation and collapse of the first structures in the universe. In this review, we describe the main chemical and physical processes occurring in the primordial gas after the recombination epoch. We also highlight the areas where improvements in the determination of reaction rates and excitation coefficients are necessary to reduce the remaining uncertainties in the predictions of the numerical models. The interaction of primordial molecules with the CBR and the role of H2 and HD cooling in the early universe are discussed. Finally, we comment on the results of recent simulations of the fragmentation and collapse of primordial clouds, with an emphasis on the typical mass scale of the first objects.
Introduction
The formation of the first stellar objects in the universe is a fascinating, yet little understood process. Although we have now observational data on bright quasars and galaxies out to redshifts of about 5 (corresponding to 109 yr after the Big Bang) and on the density fluctuations at redshifts about 1000 (or an age of ∼ 106 yr), there is no direct evidence as to when and how the first structures formed. This unique epoch and the nature of the primordial objects define what has been called the end of the “Dark Ages” (Rees 1999).
According to Big Bang cosmology, there must have been an epoch in the history of the universe during which the original gas mixture was altered by the manufacture of heavy elements inside stars.
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