32 research outputs found
Dissemination of endometrial cancer MRI staging guidelines among young radiologists: an ESUR Junior Network survey
No full textObjectives: Imaging guidelines could play an important role in the training of radiologists, but the extent of their adoption in residency programs is unclear. With this survey, the European Society of Urogenital Radiology (ESUR) Junior Network aimed to assess the dissemination of the ESUR guidelines on endometrial cancer MRI staging (EC-ESUR guidelines) among young radiologists. Methods: An online questionnaire targeted to last year radiology residents and radiologists in the first year of their career was designed. It included 24 questions, structured in 4 sections (i.e., background, general, acquisition protocol, interpretation, and reporting). The survey was active between April and May 2022, accepting answers worldwide. Answers were solicited with a social media campaign and with the support of national scientific societies. Subgroup analysis was performed based on variables such as subspecialty of interest and number of EC-ESUR guidelines consultations using the Wilcoxon rank sum test. Results: In total, 118 participants completed the questionnaire, of which 94 (80%) were from Europe and 46 (39%) with a special interest in urogenital radiology. Overall, 68 (58%) stated that the guidelines were not part of their residency teaching programs while 32 (27%) had never even consulted the guidelines. Interest in urogenital radiology as a subspecialty and EC-ESUR guidelines consultations were associated with greater confidence in supervising scan acquisition, interpreting, and reporting EC MRI staging exams. Conclusion: Four years after publication, the adoption of EC-ESUR guidelines in residency programs is heterogeneously low. Despite a possible selection bias, our findings indicate that active promotion of EC-ESUR guidelines is required. Key points: • The adoption of ESUR guidelines on endometrial cancer in radiology residency programs is heterogeneous. • Almost one third of respondents stated they had never even consulted the guidelines. • Confidence toward guidelines was higher in those who were exposed to more endometrial cancer MRI staging scans. • Reading the guidelines was associated with a greater confidence in protocol acquisition, interpretation, and reporting. • Active efforts to promote their dissemination are required
Setting the Table for a Sustainable and Just Food System
No full text· As consumers and producers, people of color have been affected disproportionately by systemic problems in the food system.
· This article describes the Diversifying Leadership for Sustainable Food Policy initiative, a joint effort of the Jessie Smith Noyes Foundation and the W. K. Kellogg Foundation to build the capacity of organizations led by people of color to engage in policy and advocacy work.
· Grantees successfully built their capacity to engage in policy work (e.g., increased capacity to identify policy targets), increased their organizational capacity (e.g., diversified boards), improved their communities’ capacity (e.g., created opportunities for dialogue and improved access to fresh foods), and impacted policies related to sustainable food (e.g., provided resources for small and new farmers)
A collaborative defense mechanism against SYN flooding attacks in IP networks
No full textSYN flooding exploits the Transmission Control Protocol (TCP) three-way handshake process by sending many connection requests using spoofed source IP addresses to a victim's host. This keeps that host from handling legitimate requests, causing it to populate its backlog queue with forged TCP connections. In this article, we propose a novel defense mechanism that makes use of the edge routers that are associated with the spoofed IP addresses' networks to determine whether the incoming SYN-ACK segment is valid. This is accomplished by maintaining a matching table of the outgoing SYNs and incoming SYN-ACKs and also by using the ARP protocol. If an incoming SYN-ACK segment is not valid, the edge router resets the connection at the victim's host, freeing up an entry in the victim's backlog queue, and enabling it to accept other legitimate incoming connection requests. We also present a communication protocol to encourage collaboration between various networks to protect each other. We evaluated the performance of our proposed approach and studied its impact on the network. Our experimental and simulation results showed the efficiency of our proposed collaborative defense mechanism. © 2008 Elsevier Ltd. All rights reserved.[Anonymous], 2006, NS 2 SIMULATOR; *CERT, 1998, CA199801 CERT; CHEN YW, 2000, P NETW OP MAN S 2000, P593; *CISC SYST INC, 1998, CISC SEC ADV 7XX ROU; Cisco Systems Inc., 1999, DEF STRAT PROT TCP S; Crosby S.A., 2003, P 12 USENIX SEC S, P29; Ferguson P., 2000, RFC2827; GONCALVES M, 1999, CHECK POINT FIREWALL, V1; Hu YP, 2004, PROCEEDINGS OF THE 3RD INTERNATIONAL SYMPOSIUM ON HEAT TRANSFER ENHANCEMENT AND ENERGY CONSERVATION, VOLS 1 AND 2, P39; Jin C., 2003, P 10 ACM C COMP COMM, P30; Kargl F., 2001, P 10 INT C WORLD WID, P514, DOI 10.1145-371920.372148; Karig D., 2001, CEL2001002 PRINC U D; KEROMYTIS AD, 2003, IEEE J SELECTED AREA; LEMON J, 2002, P USENIX BSDC 02 C F; LEVINE JR, 1992, O REILLY MEDIA; libpcap, 2011, LIBPCAP PACKET CAPTU; MACCLURE S, 1999, HACKING EXPOSED NETW; *NISCC, 2006, 012006 NISCC; NOURELDEIN NA, P TENCON 2000, P259; Ohsita Y., 2005, Proceedings. 14th International Conference on Computer Communications and Networks (IEEE Cat. No. 05EX1184), DOI 10.1109-ICCCN.2005.1523897; Paxson V, 2001, ACM SIGCOMM COMP COM, V31, P38, DOI 10.1145-505659.505664; Postel J., 1981, 792 RFC; Schuba CL, 1997, P IEEE S SECUR PRIV, P208, DOI 10.1109-SECPRI.1997.601338; Stevens R., 1994, TCP IP ILLUSTRATED, V1; TUPAKULA UK, 2004, P IEEE GLOB TEL C GL, P2240; VENEMA W, TCP WRAPPER NETWORK; WANG H, 2002, P 22 INT C DISTR COM, P421; Wangs H, 2002, P IEEE INFOCOM 2002, P1530; Zuquete A., 2002, P 6 IFIP COMM MULT S, P57; CYBER CRIME TARGETS; SUNS TCP SYN FLOODIN72
A critical reassessment of the role of mitochondria in tumorigenesis
No full text<p><b>Background:</b> Mitochondrial DNA (mtDNA) is being analyzed by an increasing number of laboratories in order to investigate its potential role as an active marker of tumorigenesis in various types of cancer. Here we question the conclusions drawn in most of these investigations, especially those published in high-rank cancer research journals, under the evidence that a significant number of these medical mtDNA studies are based on obviously flawed sequencing results.</p>
<p><b>Methods and Findings:</b> In our analyses, we take a phylogenetic approach and employ thorough database searches, which together have proven successful for detecting erroneous sequences in the fields of human population genetics and forensics. Apart from conceptual problems concerning the interpretation of mtDNA variation in tumorigenesis, in most cases, blocks of seemingly somatic mutations clearly point to contamination or sample mix-up and, therefore, have nothing to do with tumorigenesis.</p>
<p><b>Conclusion:</b> The role of mitochondria in tumorigenesis remains unclarified. Our findings of laboratory errors in many contributions would represent only the tip of the iceberg since most published studies do not provide the raw sequence data for inspection, thus hindering a posteriori evaluation of the results. There is no precedent for such a concatenation of errors and misconceptions affecting a whole subfield of medical research.</p>
Policy Networks. IHS Political Science Series: 2003, No. 90
No full textModern democratic governance occurs only rarely via traditional Weberian hierarchies or pure ‘markets’. Rather, public policies are made via some kind of hybrid arrangement involving a range of different actors, including some representing private or non-governmental institutions. The concept of policy networks - clusters of actors, each with an interest, or ‘stake’ in a given policy sector and the capacity to help determine policy success or failure - has been developed and refined as a way to try to describe, explain and predict the outcomes of policy-making via such hybrid arrangements. Governance by policy network is rife at the level of the European Union because it is such a highly differentiated polity which is dominated (in important ways) by experts and highly dependent on ‘government by committee’. Research on EU policy networks has produced useful results but we remain some distance away from an agreed, plausible ‘theory’ of policy networks
Open Access Bibliography: Liberating Scholarly Literature with E-Prints and Open Access Journals
No full textThe Open Access Bibliography: Liberating Scholarly Literature with E-Prints and Open Access Journals provides an overview of open access concepts, and it presents over 1,300 selected English-language books, conference papers (including some digital video presentations), debates, editorials, e-prints, journal and magazine articles, news articles, technical reports, and other printed and electronic sources that are useful in understanding the open access movement's efforts to provide free access to and unfettered use of scholarly literature. Most sources have been published between 1999 and August 31, 2004; however, a limited number of key sources published prior to 1999 are also included. Where possible, links are provided to sources that are freely available on the Internet (approximately 78 percent of the bibliography's references have such links). The 129-page bibliography has been published in print and PDF formats by the Association of Research Libraries (ARL). The print version is available from ARL. The book is licensed under the Creative Commons Attribution-NonCommercial License
A systematic review of evidence on malignant spinal metastases : natural history and technologies for identifying patients at high risk of vertebral fracture and spinal cord compression
No full textBackground: Spinal metastases can lead to significant morbidity and reduction in quality of life due to spinal cord compression (SCC). Between 5% and 20% of patients with spinal metastases develop metastatic spinal cord compression during the course of their disease. An early study estimated average survival for patients with SCC to be between 3 and 7 months, with a 36% probability of survival to 12 months. An understanding of the natural history and early diagnosis of spinal metastases and prediction of collapse of the metastatic vertebrae are important.
Objective: To undertake a systematic review to examine the natural history of metastatic spinal lesions and to identify patients at high risk of vertebral fracture and SCC.
Data sources: The search strategy covered the concepts of metastasis, the spine and adults. Searches were undertaken from inception to June 2011 in 13 electronic databases [MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations; EMBASE; Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials (CENTRAL); Database of Abstracts of Reviews of Effects (DARE), NHS Economic Evaluation Database (NHS EED), HTA databases (NHS Centre for Reviews and Dissemination); Science Citation Index and Conference Proceedings (Web of Science); UK Clinical Research Network (UKCRN) Portfolio Database; Current Controlled Trials; ClinicalTrials.gov].
Review methods: Titles and abstracts of retrieved studies were assessed by two reviewers independently. Disagreement was resolved by consensus agreement. Full data were extracted independently by one reviewer. All included studies were reviewed by a second researcher with disagreements resolved by discussion. A quality assessment instrument was used to assess bias in six domains: study population, attrition, prognostic factor measurement, outcome measurement, confounding measurement and account, and analysis. Data were tabulated and discussed in a narrative review. Each tumour type was looked at separately.
Results: In all, 2425 potentially relevant articles were identified, of which 31 met the inclusion criteria. No study examined natural history alone. Seventeen studies reported retrospective data, 10 were prospective studies, and three were other study designs. There was one systematic review. There were no randomised controlled trials (RCTs). Approximately 5782 participants were included. Sample sizes ranged from 41 to 859. The age of participants ranged between 7 and 92 years. Types of cancers reported on were lung alone (n= 3), prostate alone (n= 6), breast alone (n= 7), mixed cancers (n= 13) and unclear (n= 1). A total of 93 prognostic factors were identified as potentially significant in predicting risk of SCC or collapse. Overall findings indicated that the more spinal metastases present and the longer a patient was at risk, the greater the reported likelihood of development of SCC and collapse. There was an increased risk of developing SCC if a cancer had already spread to the bones. In the prostate cancer studies, tumour grade, metastatic load and time on hormone therapy were associated with increased risk of SCC. In one study, risk of SCC before death was 24%, and 2.37 times greater with a Gleason score 7 than with a score of < 7 (p= 0.003). Other research found that patients with six or more bone lesions were at greater risk of SCC than those with fewer than six lesions [odds ratio (OR) 2.9, 95% confidence interval (CI) 1.012 to 8.35, p= 0.047]. For breast cancer patients who received a computerised tomography (CT) scan for suspected SCC, multiple logistic regression in one study identified four independent variables predictive of a positive test: bone metastases 2 years (OR 3.0 95% CI 1.2 to 7.6; p= 0.02); metastatic disease at initial diagnosis (OR 3.4, 95% CI 1.0 to 11.4; p= 0.05); objective weakness (OR 3.8, 95% CI 1.5 to 9.5; p= 0.005); and vertebral compression fracture on spine radiograph (OR 2.6, 95% CI 1.0 to 6.5; p= 0.05). A further study on mixed cancers, among patients who received surgery for SCC, reported that vertebral body compression fractures were associated with presurgery chemotherapy (OR 2.283, 95% CI 1.064 to 4.898; p= 0.03), cancer type [primary breast cancer (OR 4.179, 95% CI 1.457 to 11.983; p= 0.008)], thoracic involvement (OR 3.505, 95% CI 1.343 to 9.143; p= 0.01) and anterior cord compression (OR 3.213, 95% CI 1.416 to 7.293; p= 0.005).
Limitations: Many of the included studies provided limited information about patient populations and selection criteria and they varied in methodological quality, rigour and transparency. Several studies identified type of cancer (e.g. breast, lung or prostate cancer) as a significant factor in predicting SCC, but it remains difficult to determine the risk differential partly because of residual bias. Consideration of quantitative results from the studies does not easily allow generation of a coherent numerical summary, studies were heterogeneous especially with regard to population, results were not consistent between studies, and study results almost universally lacked corroboration from other independent studies.
Conclusion: No studies were found which examined natural history. Overall burden of metastatic disease, confirmed metastatic bone involvement and immediate symptomatology suggestive of spinal column involvement are already well known as factors for metastatic SCC, vertebral collapse or progression of vertebral collapse. Although we identified a large number of additional possible prognostic factors, those which currently offer the most potential are unclear. Current clinical consensus favours magnetic resonance imaging and CT imaging modalities for the investigation of SCC and vertebral fracture. Future research should concentrate on: (1) prospective randomised designs to establish clinical and quality-of-life outcomes and cost-effectiveness of identification and treatment of patients at high risk of vertebral collapse and SCC; (2) Service Delivery and Organisation research on magnetic resonance imaging (MRI) scans and scanning (in tandem with research studies on use of MRI to monitor progression) in order to understand best methods for maximising use of MRI scanners; and (3) investigation of prognostic algorithms to calculate probability of a specified event using high-quality prospective studies, involving defined populations, randomly selected and clearly identified samples, and with blinding of investigators
RNAseq analysis of fast skeletal muscle in restriction-fed transgenic coho salmon (Oncorhynchus kisutch) : an experimental model uncoupling the growth hormone and nutritional signals regulating growth
No full textBackground Coho salmon (Oncorhynchus kisutch) transgenic for growth hormone (Gh) express Gh in multiple tissues which results in increased appetite and continuous high growth with satiation feeding. Restricting Gh-transgenics to the same lower ration (TR) as wild-type fish (WT) results in similar growth, but with the recruitment of fewer, larger diameter, muscle skeletal fibres to reach a given body size. In order to better understand the genetic mechanisms behind these different patterns of muscle growth and to investigate how the decoupling of Gh and nutritional signals affects gene regulation we used RNA-seq to compare the fast skeletal muscle transcriptome in TR and WT coho salmon. Results Illumina sequencing of individually barcoded libraries from 6 WT and 6 TR coho salmon yielded 704,550,985 paired end reads which were used to construct 323,115 contigs containing 19,093 unique genes of which >10,000 contained >90 % of the coding sequence. Transcripts coding for 31 genes required for myoblast fusion were identified with 22 significantly downregulated in TR relative to WT fish, including 10 (vaspa, cdh15, graf1, crk, crkl, dock1, trio, plekho1a, cdc42a and dock5) associated with signaling through the cell surface protein cadherin. Nineteen out of 44 (43 %) translation initiation factors and 14 of 47 (30 %) protein chaperones were upregulated in TR relative to WT fish. Conclusions TR coho salmon showed increased growth hormone transcripts and gene expression associated with protein synthesis and folding than WT fish even though net rates of protein accretion were similar. The uncoupling of Gh and amino acid signals likely results in additional costs of transcription associated with protein turnover in TR fish. The predicted reduction in the ionic costs of homeostasis in TR fish associated with increased fibre size were shown to involve multiple pathways regulating myotube fusion, particularly cadherin signaling.Peer reviewe
Universal service obligations in utility concession contracts and the needs of the poor in Argentina's privatization
No full textThe authors summarize the main lessons emerging from Argentina's experience, including universal service obligations in concession contracts. They discuss free-riding risks, moral hazard problems, and other issues that arise when social concerns are delegated to private operators. After reporting on Argentina's experience, the authors suggest some guidelines: 1) Anticipate interjurisdictional externalities. Users'mobility makes targeting service obligations difficult. 2) Minimize the risks imposed by elusive demand. In providing new services, a gradual policy may work better than a"shock". 3) Realize that unemployment leads to delinquency and lower expected tariffs. Elasticity of fixed and usage charges is important. 4) Deal with the fact that the poor have limited access to credit. Ultimately, plans that included credit for the payment of infrastructure charges were not that successful. 5) Coordinate regulatory, employment, and social policy. One successful plan to provide universal service involved employing workers from poor families in infrastructure extension works. 6) Beware of the latent opportunism of users who benefit from special programs. Special treatment of a sector may encourage free-riding (for example, pensioners overused the telephone until a limit was placed on the number of subsidized phone calls they could make). 7) Fixed allocations for payment of services do not ensure that universal service obligations will be met. How do you deal with the problem that many pensioners do not pay their bills? 8) anticipate that operators will have more information than regulators do. If companies exaggerate supply costs in remote areas, direct interaction with poor users there may lead to the selection of more cost-effective technologies. 9)"Tailored"programs are often much more effective than standardized programs. They are clearly more expensive but, when demand-driven, are also more effective.Payment Systems&Infrastructure,Economic Theory&Research,Enterprise Development&Reform,Decentralization,Environmental Economics&Policies,Governance Indicators,Health Economics&Finance,Consumption,Environmental Economics&Policies,Economic Theory&Research
Returning culture to peacebuilding : contesting the liberal peace in Sierra Leone
No full textThis thesis investigates the advantages and limitations of applying culture to the analysis of violent conflict and peacebuilding, with a particular focus on liberal peacebuilding in Sierra Leone. While fully aware of the critique of the concept of culture in terms of its uses for the production of difference and ‘otherness,’ it also seeks to respond to the critique of liberal peacebuilding on the account of its low sensitivity towards local culture, which allegedly undermines the peace effort. After a careful examination of the terms of discussion about culture enabled by theoretical approaches to conflict in Chapter 2, the thesis presents a theoretical framework for the analysis of cultural aspects of conflict and peace based on the processes and effects of meaning-generation (Chapter 3), developing the conceptual apparatus and vocabulary for the subsequent empirical study. Instead of bracketing out the recursive nature of cultural theorising, the developed approach embraces the recursive dynamics which arise as a result of cultural ‘embeddedness’ of the analyst and the processes which s/he seeks to elucidate, mirroring similar dynamics in the cultural production of meaning and knowledge. The framework of ‘embedded cultural enquiry’ is then used to analyse the practices of liberal peacebuilding as a particular culture, which shapes the interaction of the liberal peace with its ‘subjects’ and critics as well as framing its reception of the cultural problematic generally (Chapter 4). The application of the analytical framework to the case study investigates the interaction between the liberal peace and ‘local culture,’ offering an alternative reading of the conflict and peace process in Sierra Leone (Chapter 5). The study concludes that a greater attention to cultural meaning-making offers a largely untapped potential for peacebuilding, although any decisions with regard to its deployment will inevitably be made from within an inherently biased cultural perspective
