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Spearman CW, Desalegn H, Ocama P, Awuku YA, Ojo O, Elsahhar M, Abdo AA, Ndububa DA, Fouad Y, Borodo MM, Ng'wanasayi M, Ally R, Elwakil R. The sub-Saharan Africa position statement on the redefinition of fatty liver disease: From NAFLD to MAFLD. J Hepatol 2021; 74:1256-1258. [PMID: 33484771 DOI: 10.1016/j.jhep.2021.01.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 01/07/2021] [Accepted: 01/10/2021] [Indexed: 02/08/2023]
Affiliation(s)
- C Wendy Spearman
- Division of Hepatology, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa
| | - Hailemichael Desalegn
- Medical Department, St. Paul's Hospital, Millennium Medical College, Addis Ababa, Ethiopia
| | - Ponsiano Ocama
- School of Medicine, Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Yaw Asante Awuku
- Department of Medicine and Therapeutics, School of Medicine, University of Health and Allied Sciences, Ho, Ghana
| | - Olusegun Ojo
- Gastroenterology and Liver Pathology Unit, Department of Morbid Anatomy, Obafemi Awolowo University and Teaching Hospital Complex, Ile Ife, Nigeria
| | - Medhat Elsahhar
- Egyptian Association for the Study of Liver and Gastrointestinal Disease (EASLGD), Police Medical Academy, Cairo, Egypt
| | | | - Dennis Amajuoyi Ndububa
- Department of Medicine, Faculty of Clinical Sciences, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
| | - Yasser Fouad
- Department of Gastroenterology, Hepatology and Endemic Medicine, Faculty of Medicine, Minia University, Minia, Egypt
| | | | | | - Reidwan Ally
- Departement of Gastroenterology, University of Witwatersr, Chris Hani Baraguanath Academic Hospital, Johansberg, South Africa
| | - Reda Elwakil
- Tropical Medicine Department, Faculty of Medicine, Ain Shams University, Egypt.
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Al-Qahtani AA, Al-Anazi MR, Nazir N, Wani K, Abdo AA, Sanai FM, Khan MQ, Al-Ashgar HI, Albenmousa A, Al-Hamoudi WK, Alswat KA, Al-Ahdal MN. Association of single nucleotide polymorphisms in microRNAs with susceptibility to hepatitis B virus infection and HBV-related liver complications: A study in a Saudi Arabian population. J Viral Hepat 2017; 24:1132-1142. [PMID: 28685993 DOI: 10.1111/jvh.12749] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 05/26/2017] [Indexed: 12/14/2022]
Abstract
The aim of this study was to evaluate the association of 10 SNPs in different microRNAs (miRNAs) with susceptibility to hepatitis B virus (HBV) infection, HBV clearance, persistence of chronic HBV infection, and progression to liver cirrhosis and hepatocellular carcinoma (HCC). Patients were categorized into the following groups: inactive HBV carrier, active HBV carrier, HBV-cleared subject and cirrhosis+HCC. Samples were analysed for 10 SNPs in microRNAs using either PCR-based genotyping or the TaqMan assay. We found that rs1358379 was associated with susceptibility to HBV infection, HBV clearance, persistent chronic HBV infection and liver cirrhosis+HCC. In addition, we found that rs2292832 and rs11614913 were associated with risk of HBV infection, viral clearance and cirrhosis+HCC, whereas rs2910164 was associated with proneness to HBV infection, and ability to clear the virus. There was evidence of associations between rs6505162 and HBV clearance and the development of liver disease, whereas a single association was found between rs2289030 and HBV clearance. Similarly, rs7372209 and rs4919510 were specifically associated with the development of HBV-induced liver complications. SNPs in miRNAs affect the susceptibility, clearance and progression of HBV infection in Saudi Arabian patients. We found, using Gene Ontology or pathway analyses, that these genes may contribute to the pathophysiology of HBV infection and related liver complications. However, differences in the association of examined SNPs with various clinical stages indicate variations in the respective functional roles of these polymorphisms and their miRNAs, and thus, further investigation to fully explore their therapeutic potential is warranted.
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Affiliation(s)
- A A Al-Qahtani
- Department of Infection and Immunity, Research Center, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia.,Department of Microbiology and Immunology, Alfaisal University School of Medicine, Riyadh, Saudi Arabia
| | - M R Al-Anazi
- Department of Infection and Immunity, Research Center, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - N Nazir
- Department of Infection and Immunity, Research Center, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - K Wani
- Biomarkers Research Program, Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - A A Abdo
- Gastroenterology Section, Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia.,Liver Disease Research Center, King Saud University, Riyadh, Saudi Arabia
| | - F M Sanai
- Liver Disease Research Center, King Saud University, Riyadh, Saudi Arabia.,Gastroenterology Section, Department of Medicine, King Abdulaziz Medical City, Jeddah, Saudi Arabia
| | - M Q Khan
- Department of Medicine, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - H I Al-Ashgar
- Department of Medicine, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - A Albenmousa
- Department of Gastroenterology & Hepatology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - W K Al-Hamoudi
- Gastroenterology Section, Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia.,Liver Disease Research Center, King Saud University, Riyadh, Saudi Arabia
| | - K A Alswat
- Gastroenterology Section, Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia.,Liver Disease Research Center, King Saud University, Riyadh, Saudi Arabia
| | - M N Al-Ahdal
- Department of Infection and Immunity, Research Center, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia.,Department of Microbiology and Immunology, Alfaisal University School of Medicine, Riyadh, Saudi Arabia
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3
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Arabi NA, Musaad AM, Ahmed EE, Abdo AA, Elhassan AM, Hassan H, Adam N, Abdelazeem M, Ibnouf MA. Primary extragastrointestinal stromal tumour of the whole abdominal cavity, omentum, peritoneum and mesentery: a case report and review of the literature. J Med Case Rep 2014; 8:337. [PMID: 25303935 PMCID: PMC4197940 DOI: 10.1186/1752-1947-8-337] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 08/26/2014] [Indexed: 02/08/2023] Open
Abstract
Introduction The gastrointestinal stromal tumour is one of the common mesenchymal tumours of the gastrointestinal tract. It originates from the interstitial cells of Cajal. Gastrointestinal stromal tumours that present outside the gastrointestinal tract are called extragastrointestinal stromal tumours; they share the same morphological and immunohistochemical characteristics. Here we describe an unusual case of extragastrointestinal stromal tumour that presented with gooseberry-like multiple nodules involving the whole abdominal cavity. Case presentation A 65-year-old Sudanese man presented with vague abdominal pain and progressive abdominal distension for 6 months. The pain was associated with mild loss of weight despite good appetite. A physical examination revealed distended abdomen with multiple firm nodules involving his whole abdomen. The results of haematological tests were within normal range. Ultrasound of his abdomen showed multiple nodules of varying sizes in the peritoneal cavity. A computed tomography scan of his abdomen showed numerous nodules of different sizes (1 to 3cm in diameter) filling the whole peritoneal cavity with intense peripheral enhancement. Ultrasound-guided biopsy was not informative. Upper and lower gastrointestinal endoscopies were normal. Exploration of his abdomen revealed multiple firm gooseberry-like nodules of different sizes involving the greater omentum, peritoneal cavity and the mesentery. The liver, spleen and pancreas were normal. The result of the histopathology was conclusive for gastrointestinal stromal tumour. Conclusions Here we present a rare case of extragastrointestinal stromal tumour in a patient who presented with vague abdominal pain and progressive abdominal distension. A laparotomy showed gooseberry-like multiple nodules of different sizes involving his whole abdominal cavity. He underwent debulking surgery and received imatinib.
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Alhamlan FS, Al-Ahdal MN, Khalaf NZ, Abdo AA, Sanai FM, Al-Ashgar HI, Elhefnawi M, Zaid A, Al-Qahtani AA. Hepatitis C virus genotype 1: how genetic variability of the core protein affects the response to pegylated-interferon and ribavirin therapy. J Med Virol 2013; 86:224-34. [PMID: 24166351 DOI: 10.1002/jmv.23823] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2013] [Indexed: 12/29/2022]
Abstract
Hepatitis C virus subgenotypes 1a and 1b are found worldwide and cause 60% of all hepatitis C cases. It has been reported recently that viral genetic variations have a critical impact on the patient treatment outcome. In particular, polymorphisms of the HCV core protein have been linked to poor treatment response. However, most of these studies were conducted on Asian populations, Japanese in particular who are infected with HCV subgenotype 1b. Hence, we aimed in this study to examine the core protein polymorphisms in Saudi patients who are infected with chronic HCV genotype 1 (1a and 1b subtypes) and its association with treatment outcome. Direct sequencing of full-length core protein and data mining analyses were utilized. Results have shown that the response to treatment is dependent on subgenotypes. Indeed, HCV-1b showed different point mutations that are associated with treatment outcome where the point mutations at positions 70 (Arg(70) Gln) and 75 (Thr(75) Ala) in HCV-1b are significantly associated with PEG-IFN/RBV treatment response. In contrast, HCV-1a showed no significant association between core protein mutations and response to treatment. In addition, analyses of HCV-1a core protein sequences revealed a highly conserved region especially in the responder group. This study provides a new insight in the genetic variability of full-length core protein in HCV genotype 1 in Saudi infected patients.
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Affiliation(s)
- F S Alhamlan
- Department of Infection and Immunity, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
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5
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Sanai FM, Helmy A, Bzeizi KI, Babatin MA, Al-Qahtani A, Al-Ashgar HA, Al-Mdani AS, Al-Akwaa A, Almutharea S, Khan MQ, Alghamdi AS, Farah T, Al-Hamoudi W, Saadeh M, Abdo AA. Discriminant value of serum HBV DNA levels as predictors of liver fibrosis in chronic hepatitis B. J Viral Hepat 2011; 18:e217-25. [PMID: 21692936 DOI: 10.1111/j.1365-2893.2011.01437.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Current guidelines recommend antiviral therapy in chronic hepatitis B (HBV) patients with significant histological disease. We aimed to compare histological fibrosis (METAVIR, ≥F2) in patients with HBV DNA ≥20,000 IU/mL vs. ≥2000 IU/mL and identify predictors of fibrosis. We performed prospective liver biopsies on 203 HBeAg-negative patients in four groups: Group I (n = 55): HBV DNA ≥20,000 IU/mL and persistently elevated alanine aminotransferase (ALT) levels (PEALT; >40 U/L); Group II (n = 34): HBV DNA ≥20,000 IU/mL and persistently normal ALT (PNALT); Group III (n = 40): HBV DNA <20,000 IU/mL and PEALT; and Group IV (n = 74): HBV DNA <20,000 IU/mL, and PNALT. We reanalysed all groups in relation to updated cut-off for treatable viremia (2000 IU/mL). Genotype D was detected in 86% of patients. Hepatic fibrosis ≥F2 was detected in 72.7%, 52.9%, 57.5% and 18.9% in Groups I-IV, respectively (P < 0.0001). Except in Group II with a trend for lower ≥F2 fibrosis (P = 0.067), there was no significant difference by using HBV DNA cut-off 20,000 vs. 2000 IU/mL. Multivariate logistic regression analysis identified study Group IV (OR, 0.0276; CI: 0.088-0.868; P = 0.0276) and milder (A0-1) necroinflammatory grade (OR, 0.135; CI: 0.063-0.287; P < 0.0001) as independent predictors of ≥F2 fibrosis. The specificity, positive and negative predictive values for PEALT in detection of ≥F2 fibrosis for viremia ≥2000 IU/mL (80%, 69% and 65%, respectively) or ≥20,000 IU/mL (86%, 73% and 63%, respectively) were similar, with a marginal gain in sensitivity (51% vs. 42%, respectively). Significant fibrosis is prevalent in a large proportion of HBeAg-negative patients with high viremia and persistently normal ALT. Lower HBV DNA cut-offs could be adopted with marginal gains in fibrosis detection and without loss of diagnostic accuracy.
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Affiliation(s)
- F M Sanai
- Department of Hepatobiliary Sciences, King Abdulaziz Medical City, Riyadh, KSA.
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Abdo AA, Ackermann M, Ajello M, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bouvier A, Brandt TJ, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett TH, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Carrigan S, Casandjian JM, Cecchi C, Celik O, Charles E, Chaty S, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Corbel S, Corbet R, DeCesar ME, den Hartog PR, Dermer CD, de Palma F, Digel SW, Donato D, do Couto e Silva E, Drell PS, Dubois R, Dubus G, Dumora D, Favuzzi C, Fegan SJ, Ferrara EC, Fortin P, Frailis M, Fuhrmann L, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guiriec S, Hadasch D, Harding AK, Hayashida M, Hays E, Healey SE, Hill AB, Horan D, Hughes RE, Itoh R, Jean P, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kerr M, Knödlseder J, Koerding E, Kuss M, Lande J, Latronico L, Lee SH, Lemoine-Goumard M, Garde ML, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Makeev A, Mazziotta MN, McConville W, McEnery JE, Mehault J, Michelson PF, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nakamori T, Naumann-Godo M, Nestoras I, Nolan PL, Norris JP, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes JF, Ozaki M, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Rainò S, Rando R, Ray PS, Razzano M, Razzaque S, Rea N, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Romani RW, Roth M, Sadrozinski HFW, Sander A, Parkinson PMS, Scargle JD, Schinzel FK, Sgrò C, Shaw MS, Siskind EJ, Smith DA, Smith PD, Sokolovsky KV, Spandre G, Spinelli P, Stawarz Ł, Strickman MS, Suson DJ, Takahashi H, Takahashi T, Tanaka T, Tanaka Y, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wallace E, Wang P, Winer BL, Wolff MT, Wood KS, Yang Z, Ylinen T, Ziegler M, Maehara H, Nishiyama K, Kabashima F, Bach U, Bower GC, Falcone A, Forster JR, Henden A, Kawabata KS, Koubsky P, Mukai K, Nelson T, Oates SR, Sakimoto K, Sasada M, Shenavrin VI, Shore SN, Skinner GK, Sokoloski J, Stroh M, Tatarnikov AM, Uemura M, Wahlgren GM, Yamanaka M. Gamma-ray emission concurrent with the nova in the symbiotic binary V407 Cygni. Science 2010; 329:817-21. [PMID: 20705855 DOI: 10.1126/science.1192537] [Citation(s) in RCA: 146] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce pi(0) decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.
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Affiliation(s)
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- Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA
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Allam N, Al Saghier M, El Sheikh Y, Al Sofayan M, Khalaf H, Al Sebayel M, Helmy A, Kamel Y, Aljedai A, Abdel-Dayem H, Kenetman NM, Al Saghier A, Al Hamoudi W, Abdo AA. Clinical outcomes for Saudi and Egyptian patients receiving deceased donor liver transplantation in China. Am J Transplant 2010; 10:1834-41. [PMID: 20353478 DOI: 10.1111/j.1600-6143.2010.03088.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Long waiting list times in liver transplant programs in Saudi Arabia and unavailability of deceased donor transplantation in Egypt have led several patients to seek transplantation in China. All patients who received transplants in China and followed in three centers from January 2003-January 2007 were included. All patients' charts were reviewed. Mortality and morbidity were compared to those transplanted in King Faisal Specialist Hospital & Research Centre (KFSH&RC) during the same period. Seventy-four adult patients were included (46 Saudi nationals; 28 Egyptians). One-year and 3-year cumulative patient survival rates were 83% and 62%, respectively compared to 92% and 84% in KFSH&RC. One-year and 3-year cumulative graft survival rates were 81% and 59%, respectively compared to 90% and 84% in KFSH&RC. Compared to KFSH&RC, the incidence of complications was significantly higher especially biliary complications, sepsis, metastasis and acquired HBV infection posttransplant. Requirements of postoperative interventions and hospital admissions were also significantly greater. Our data show high mortality and morbidity rates in Saudi and Egyptian patients receiving transplants in China. This could be related to more liberal selection criteria, use of donation after cardiac death (DCD) donors or possibly more limited posttransplant care.
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Affiliation(s)
- N Allam
- Department of Hepatology, Menofeya University, Egypt
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Abdo AA, Ackermann M, Ajello M, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cavazzuti E, Cecchi C, Celik O, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Cominsky LR, Conrad J, Costamante L, Cutini S, Davis DS, Dermer CD, de Angelis A, de Palma F, Digel SW, do Couto e Silva E, Drell PS, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan SJ, Finke J, Focke WB, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Georganopoulos M, Germani S, Giebels B, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier IA, Grove JE, Guillemot L, Guiriec S, Hanabata Y, Harding AK, Hayashida M, Hays E, Hughes RE, Jackson MS, Jóhannesson G, Johnson AS, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Rainò S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Romani RW, Roth M, Ryde F, Sadrozinski HFW, Sambruna R, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Sgrò C, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Stawarz Ł, Strickman MS, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wallace E, Wang P, Winer BL, Wood KS, Ylinen T, Ziegler M, Hardcastle MJ, Kazanas D. Fermi Gamma-Ray Imaging of a Radio Galaxy. Science 2010; 328:725-9. [PMID: 20360067 DOI: 10.1126/science.1184656] [Citation(s) in RCA: 175] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Abdo AA, Ackermann M, Ajello M, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cavazzuti E, Cecchi C, Celik O, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky LR, Conrad J, Cutini S, Dermer CD, de Angelis A, de Palma F, Digel SW, Di Bernardo G, do Couto e Silva E, Drell PS, Drlica-Wagner A, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Gustafsson M, Hanabata Y, Harding AK, Hayashida M, Hughes RE, Itoh R, Jackson MS, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Roth M, Ryde F, Sadrozinski HFW, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Sellerholm A, Sgrò C, Shaw MS, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Strickman MS, Strong AW, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wang P, Winer BL, Wood KS, Ylinen T, Ziegler M. Spectrum of the isotropic diffuse gamma-ray emission derived from first-year Fermi Large Area Telescope data. Phys Rev Lett 2010; 104:101101. [PMID: 20366411 DOI: 10.1103/physrevlett.104.101101] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Indexed: 05/29/2023]
Abstract
We report on the first Fermi Large Area Telescope (LAT) measurements of the so-called "extragalactic" diffuse gamma-ray emission (EGB). This component of the diffuse gamma-ray emission is generally considered to have an isotropic or nearly isotropic distribution on the sky with diverse contributions discussed in the literature. The derivation of the EGB is based on detailed modeling of the bright foreground diffuse Galactic gamma-ray emission, the detected LAT sources, and the solar gamma-ray emission. We find the spectrum of the EGB is consistent with a power law with a differential spectral index gamma = 2.41 +/- 0.05 and intensity I(>100 MeV) = (1.03 +/- 0.17) x 10(-5) cm(-2) s(-1) sr(-1), where the error is systematics dominated. Our EGB spectrum is featureless, less intense, and softer than that derived from EGRET data.
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Affiliation(s)
- A A Abdo
- Space Science Division, Naval Research Laboratory, Washington, D.C. 20375, USA
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Abdo AA, Ackermann M, Ajello M, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom ED, Bonamente E, Borgland AW, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Carrigan S, Casandjian JM, Cecchi C, Celik O, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer CD, de Angelis A, de Palma F, Digel SW, do Couto E Silva E, Drell PS, Drlica-Wagner A, Dubois R, Dumora D, Edmonds Y, Essig R, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grove JE, Guillemot L, Guiriec S, Gustafsson M, Hadasch D, Harding AK, Horan D, Hughes RE, Jackson MS, Jóhannesson G, Johnson AS, Johnson RP, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kuss M, Lande J, Latronico L, Llena Garde M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Makeev A, Mazziotta MN, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Ozaki M, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Rodriguez AY, Roth M, Sadrozinski HFW, Sander A, Parkinson PMS, Scargle JD, Schalk TL, Sellerholm A, Sgrò C, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Strickman MS, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JB, Thayer JG, Tibaldo L, Torres DF, Uchiyama Y, Usher TL, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wang P, Winer BL, Wood KS, Ylinen T, Ziegler M. Fermi large area telescope search for photon lines from 30 to 200 GeV and dark matter implications. Phys Rev Lett 2010; 104:091302. [PMID: 20366979 DOI: 10.1103/physrevlett.104.091302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Indexed: 05/29/2023]
Abstract
Dark matter (DM) particle annihilation or decay can produce monochromatic gamma rays readily distinguishable from astrophysical sources. gamma-ray line limits from 30 to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a gamma-ray line analysis, and integrated over most of the sky. We obtain gamma-ray line flux upper limits in the range 0.6-4.5x10{-9} cm{-2} s{-1}, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed.
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Affiliation(s)
- A A Abdo
- Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA
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Abdo AA, Ackermann M, Ajello M, Anderson B, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dereli H, Dermer CD, de Angelis A, de Palma F, Digel SW, Di Bernardo G, Dormody M, do Couto e Silva E, Drell PS, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Hanabata Y, Harding AK, Hayashida M, Hays E, Hughes RE, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, Kuehn F, Kuss M, Lande J, Latronico L, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes JF, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez AY, Roth M, Ryde F, Sadrozinski HFW, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Sellerholm A, Sgrò C, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Stecker FW, Striani E, Strickman MS, Strong AW, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wang P, Winer BL, Wood KS, Ylinen T, Ziegler M. Fermi large area telescope measurements of the diffuse gamma-ray emission at intermediate galactic latitudes. Phys Rev Lett 2009; 103:251101. [PMID: 20366246 DOI: 10.1103/physrevlett.103.251101] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Indexed: 05/29/2023]
Abstract
The diffuse galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray Observatory indicated excess gamma-ray emission greater, > or approximately equal to 1 GeV relative to diffuse galactic gamma-ray emission models consistent with directly measured CR spectra (the so-called "EGRET GeV excess"). The Large Area Telescope (LAT) instrument on the Fermi Gamma-Ray Space Telescope has measured the diffuse gamma-ray emission with improved sensitivity and resolution compared to EGRET. We report on LAT measurements for energies 100 MeV to 10 GeV and galactic latitudes 10 degrees < or = |b| < or = 20 degrees. The LAT spectrum for this region of the sky is well reproduced by a diffuse galactic gamma-ray emission model that is consistent with local CR spectra and inconsistent with the EGRET GeV excess.
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Affiliation(s)
- A A Abdo
- Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA
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Abdo AA, Ackermann M, Ajello M, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Celik O, Charles E, Chaty S, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dermer CD, de Palma F, Digel SW, Dormody M, do Couto e Silva E, Drell PS, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grove JE, Guillemot L, Guiriec S, Hanabata Y, Harding AK, Hayashida M, Hays E, Horan D, Hughes RE, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kawai N, Kerr M, Knödlseder J, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Makeev A, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pierbattista M, Piron F, Porter TA, Rainò S, Rando R, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Romani RW, Roth M, Ryde F, Sadrozinski HFW, Sanchez D, Sander A, Saz Parkinson PM, Sgrò C, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Strickman MS, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Vasileiou V, Vilchez N, Vitale V, Wang P, Webb N, Winer BL, Wood KS, Ylinen T, Ziegler M. Detection of high-energy gamma-ray emission from the globular cluster 47 Tucanae with Fermi. Science 2009; 325:845-8. [PMID: 19679807 DOI: 10.1126/science.1177023] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We report the detection of gamma-ray emissions above 200 megaelectron volts at a significance level of 17sigma from the globular cluster 47 Tucanae, using data obtained with the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. Globular clusters are expected to emit gamma rays because of the large populations of millisecond pulsars that they contain. The spectral shape of 47 Tucanae is consistent with gamma-ray emission from a population of millisecond pulsars. The observed gamma-ray luminosity implies an upper limit of 60 millisecond pulsars present in 47 Tucanae.
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Affiliation(s)
- A A Abdo
- Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA
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13
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Abdo AA, Ackermann M, Ajello M, Anderson B, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring MG, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Bignami GF, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Celik O, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dermer CD, de Angelis A, de Luca A, de Palma F, Digel SW, Dormody M, do Couto e Silva E, Drell PS, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan SJ, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Gwon C, Hanabata Y, Harding AK, Hayashida M, Hays E, Hughes RE, Jóhannesson G, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Marelli M, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter TA, Primack JR, Rainò S, Rando R, Ray PS, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Romani RW, Ryde F, Sadrozinski HFW, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Sgrò C, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Strickman MS, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JG, Thompson DJ, Tibaldo L, Tibolla O, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Van Etten A, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wang P, Watters K, Winer BL, Wolff MT, Wood KS, Ylinen T, Ziegler M. Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT. Science 2009; 325:840-4. [PMID: 19574346 DOI: 10.1126/science.1175558] [Citation(s) in RCA: 237] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently only seven were observed to pulse in gamma rays, and these were all discovered at other wavelengths. The Fermi Large Area Telescope (LAT) makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics, and the energetics of pulsar wind nebulae and supernova remnants.
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Affiliation(s)
- A A Abdo
- Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA
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Abdo AA, Ackermann M, Ajello M, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Battelino M, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bogaert G, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Carlson P, Casandjian JM, Cecchi C, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky LR, Conrad J, Cutini S, Dermer CD, de Angelis A, de Palma F, Digel SW, Di Bernardo G, do Couto E Silva E, Drell PS, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Focke WB, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grasso D, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Hanabata Y, Harding AK, Hartman RC, Hayashida M, Hays E, Hughes RE, Jóhannesson G, Johnson AS, Johnson RP, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocevski D, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Massai MM, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Moretti E, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Ozaki M, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Pohl M, Porter TA, Profumo S, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Romani RW, Roth M, Ryde F, Sadrozinski HFW, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Schalk TL, Sellerholm A, Sgrò C, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Stephens TE, Strickman MS, Strong AW, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, Tibolla O, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Van Etten A, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wallace E, Wang P, Winer BL, Wood KS, Ylinen T, Ziegler M. Measurement of the cosmic ray e+ +e- spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope. Phys Rev Lett 2009; 102:181101. [PMID: 19518855 DOI: 10.1103/physrevlett.102.181101] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Indexed: 05/27/2023]
Abstract
Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m;{2} sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.
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Affiliation(s)
- A A Abdo
- National Research Council Research Associate and Space Science Division, Naval Research Laboratory, Washington, D.C. 20375, USA
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Abdo AA, Allen B, Aune T, Berley D, Blaufuss E, Casanova S, Chen C, Dingus BL, Ellsworth RW, Fleysher L, Fleysher R, Gonzalez MM, Goodman JA, Hoffman CM, Hüntemeyer PH, Kolterman BE, Lansdell CP, Linnemann JT, McEnery JE, Mincer AI, Nemethy P, Noyes D, Pretz J, Ryan JM, Parkinson PMS, Shoup A, Sinnis G, Smith AJ, Sullivan GW, Vasileiou V, Walker GP, Williams DA, Yodh GB. Discovery of localized regions of excess 10-TeV cosmic rays. Phys Rev Lett 2008; 101:221101. [PMID: 19113471 DOI: 10.1103/physrevlett.101.221101] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Revised: 09/29/2008] [Indexed: 05/27/2023]
Abstract
The 7 year data set of the Milagro TeV observatory contains 2.2 x 10(11) events of which most are due to hadronic cosmic rays. These data are searched for evidence of intermediate scale structure. Excess emission on angular scales of approximately 10 degrees has been found in two localized regions of unknown origin with greater than 12sigma significance. Both regions are inconsistent with pure gamma-ray emission with high confidence. One of the regions has a different energy spectrum than the isotropic cosmic-ray flux at a level of 4.6sigma, and it is consistent with hard spectrum protons with an exponential cutoff, with the most significant excess at approximately 10 TeV. Potential causes of these excesses are explored, but no compelling explanations are found.
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Affiliation(s)
- A A Abdo
- Naval Research Laboratory, Washington, DC, USA
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Abdo AA, Ackermann M, Atwood WB, Baldini L, Ballet J, Barbiellini G, Baring MG, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bogaert G, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Carlson P, Casandjian JM, Cecchi C, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky LR, Conrad J, Cutini S, Davis DS, Dermer CD, de Angelis A, de Palma F, Digel SW, Dormody M, do Couto E Silva E, Drell PS, Dubois R, Dumora D, Edmonds Y, Farnier C, Focke WB, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Harding AK, Hartman RC, Hays E, Hughes RE, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Kanai Y, Kanbach G, Katagiri H, Kawai N, Kerr M, Kishishita T, Kiziltan B, Knödlseder J, Kocian ML, Komin N, Kuehn F, Kuss M, Latronico L, Lemoine-Goumard M, Longo F, Lonjou V, Loparco F, Lott B, Lovellette MN, Lubrano P, Makeev A, Marelli M, Mazziotta MN, McEnery JE, McGlynn S, Meurer C, Michelson PF, Mineo T, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nakamori T, Nolan PL, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes JF, Ozaki M, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piano G, Pieri L, Piron F, Porter TA, Rainò S, Rando R, Ray PS, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Romani RW, Roth M, Ryde F, Sadrozinski HFW, Sanchez D, Sander A, Parkinson PMS, Schalk TL, Sellerholm A, Sgrò C, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Strickman MS, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Thorsett SE, Tibaldo L, Torres DF, Tosti G, Tramacere A, Usher TL, Van Etten A, Vilchez N, Vitale V, Wang P, Watters K, Winer BL, Wood KS, Yasuda H, Ylinen T, Ziegler M. The Fermi Gamma-Ray Space Telescope discovers the pulsar in the young galactic supernova remnant CTA 1. Science 2008; 322:1218-21. [PMID: 18927355 DOI: 10.1126/science.1165572] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The pulsar, discovered through its gamma-ray pulsations, has a period of 316.86 milliseconds and a period derivative of 3.614 x 10(-13) seconds per second. Its characteristic age of 10(4) years is comparable to that estimated for the SNR. We speculate that most unidentified Galactic gamma-ray sources associated with star-forming regions and SNRs are such young pulsars.
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Affiliation(s)
- A A Abdo
- National Research Council Research Associate, National Academy of Sciences, Washington, DC 20001, USA
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González I, Abdo AA, López O, Hernández JC, Samada M, Cepero M, Ramos L, Ysla R, Madrigal G, Collera SA, Dominguez J, Diaz J, Benitez PP, Castellanos R. First 100 liver transplants at the medico-surgical research center (CIMEQ). Transplant Proc 2006; 38:2473-4. [PMID: 17097971 DOI: 10.1016/j.transproceed.2006.08.088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In July 1999 we began a liver transplant program that to October 2005 has included 100 liver transplants in 92 patients, eight retransplants, and two combined liver and kidney grafts. Twelve transplants were in pediatric patients, who showed a 92% survival rate in the first year. Fifty-four percent of the patients were male and 46% female. The most frequent etiologies of cirrhosis were 27% hepatitis virus C, 18% alcoholic, 13% cryptogenic, and 11% autoimmune. In 95% of the patients, we preserved the retrohepatic vena cava. The bile duct was reconstructed with a Kehr tube in 46% of patients with 31% using end-to-end suture with a tutor and 15% an end-to-end suture without a tutor. A hepaticojejunostomy was performed in 8%. The immunosuppression included cyclosporine (Neoral) or Prograf combined with mycophenolate mofetil or mycophenolate sodium and steroids. The most frequent biliary complications were local anastomosis leaks (6%) and stenosis (10%). The overall 1-year survival rate was 72%.
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Affiliation(s)
- I González
- Centro de Investigaciones Médico Quirúrgicas, Havana, Cuba
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Abstract
Collagenous and lymphocytic colitis are two inflammatory conditions of the colon that are often collectively referred to as microscopic colitis. The present report describes what is believed to be the third published case of familial microscopic colitis. A 55-year-old woman who suffered from chronic diarrhea was diagnosed with lymphocytic colitis on colonic biopsy. Subsequently, her 36-year-old daughter was diagnosed with collagenous colitis. The familial occurrence of these diseases may support an immunological hypothesis for their etiology. In addition, it supports the assumption that collagenous and lymphocytic colitis are two manifestations of the same disease process rather than two completely separate entities. The familial tendency of this disease may make a case for early colonoscopy and biopsy in relatives of patients diagnosed with microscopic colitis if they present with suggestive symptoms.
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Affiliation(s)
- A A Abdo
- University of British Columbia, Vancouver, Canada
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