Hasil untuk "History"

K. B. Oldham, J. Spanier, Alain Oustaloup

J. Pausas, J. Keeley

Peter A. Cawood, A. Kröner, W. Collins et al.

C. Woodman, S. Collins, L. Young

H. Allen Orr

Q. Skinner

H. Putnam

J. Cairns

L. Dickson

L. C. Cole

B. Leiner, V. Cerf, D. Clark et al.

This paper was first published online by the Internet Society in December 20031 and is being re-published in ACM SIGCOMM Computer Communication Review because of its historic import. It was written at the urging of its primary editor, the late Barry Leiner. He felt that a factual rendering of the events and activities associated with the development of the early Internet would be a valuable contribution. The contributing authors did their best to incorporate only factual material into this document. There are sure to be many details that have not been captured in the body of the document but it remains one of the most accurate renderings of the early period of development available.

H. Schulz

Michael Baur

Nancy Fraser

D. Reich, N. Patterson, D. Campbell et al.

The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved. One contentious issue is whether the settlement occurred by means of a single migration or multiple streams of migration from Siberia. The pattern of dispersals within the Americas is also poorly understood. To address these questions at a higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. Here we show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call ‘First American’. However, speakers of Eskimo–Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan speakers on both sides of the Panama isthmus, who have ancestry from both North and South America.

R. Westbrook, G. Dusheiko

There has long been evidence that hepatitis C can lead to persistent infection in a high proportion of infected individuals, and can progress to chronic liver disease, cirrhosis and hepatocellular carcinoma (HCC). The transition from acute to chronic hepatitis C is usually sub-clinical. Accurate studies of the time course for clearance of acute hepatitis C are difficult to carry out because of the silent onset of the acute disease. The likelihood of spontaneous HCV resolution is associated with several genetic factors, including IL28B inheritance and the DQB1*0301 allele of the major histocompatibility complex class II. Most data suggest that resolution in the acute phase without progression to chronic disease is not accompanied by significant disease, but minor histological lesions have been observed in anti-HCV positive, HCV RNA negative individuals. The risk of reinfection remains a possibility after clearance of acute hepatitis C. High rates of sexually-transmitted infection are being reported in HIV positive men who have sex with men (MSM). Chronic infection with HCV is the leading cause of end-stage liver disease, hepatocellular carcinoma (HCC) and liver related death in the Western world. The natural history of the chronic disease remains incompletely defined. It is generally a slowly progressive disease characterized by persistent hepatic inflammation, leading to the development of cirrhosis in approximately 10-20% of patients over 20-30 years of HCV infection. However, the published data indicate varying progression rates to cirrhosis. Overall, once cirrhosis has developed there is a 1-5% annual risk of HCC and a 3-6% annual risk of hepatic decompensation. Following an episode of decompensation the risk of death in the following year is between 15% and 20%. The high number of chronically infected individuals, the burden of disease, and the absence of a vaccine indicates that treatment will form part of the disease control but the impact, effectiveness and outcomes of treatment in various groups remain uncertain. Several studies and meta-analysis have concluded that eradication of HCV with antiviral therapy reduces the risk of HCC in patients with chronic hepatitis C, independent of fibrosis stage, but the risk is not eliminated.

K. Gallagher

M. Rowlinson, J. Hassard, S. Decker

J. Bennett

Fahimeh Pakravan, Ali Yousefian Najafabadi, Zohreh Meshkati et al.

Abstract Introduction Injuries sustained during physical activities are a common concern among athletes, with dental trauma representing a significant yet often under-addressed component. Timely and appropriate intervention is critical to successful outcomes, making the awareness and performance of first-line responders—particularly physical education graduates—an essential focus. This study evaluates their knowledge and practices regarding emergency management of dental trauma. Materials and methods This cross-sectional descriptive study assessed 206 physical education graduates in Isfahan between 2024 and 2025. Data were collected using a researcher-designed questionnaire comprising 12 targeted items, validated with a content validity ratio (CVR > 0.51) and confirmed reliability (ICC = 0.884). Statistical analysis was performed using SPSS (Version 26), including descriptive measures (mean, standard deviation, frequency) and inferential tests (independent t-tests, ANOVA). Results Participants demonstrated moderate proficiency in dental trauma awareness and self-reported practical knowledge, with an overall mean score of 9.74 ± 4.80 (scale: 0–20). Awareness and performance scores were closely aligned (9.08 ± 4.99 and 9.07 ± 5.39, respectively). Significant predictors of higher competency included academic achievement (P = 0.023), direct exposure to dental trauma (P = 0.001), engagement in high-contact sports such as martial arts (P = 0.016), and formal training in trauma management (P = 0.012). Conversely, gender, general athletic history, and school-level sports involvement were not statistically associated with performance outcomes. Conclusion Most PE graduates demonstrated limited preparedness for managing dental trauma. Academic progression, trauma exposure, and targeted training were associated with better awareness and applied knowledge. These findings support the integration of oral emergency response modules into sports education curricula and certification programs—promoting health literacy and alignment with WHO health promotion objectives.