176 research outputs found
Tailgut cyst and perineal hydatid cyst: A case report with multimodality imaging findings
A tailgut cyst is a rare developmental lesion and usually is located in the retrorectal or presacral space. Extrahepatic hydatid disease has been reported in several locations including the pelvis and it often poses a diagnostic challenge. There are very few reported cases of primary perineal hydatid cysts. We present the multimodality imaging findings of a tailgut cyst and concurrent perineal hydatid disease in a 32-year-old male patient
Energy-Aware Streaming Multimedia Adaptation: An Educational Perspective
As mobile devices are getting more powerful and more affordable the use of online educational multimedia is also getting very prevalent. Limited battery power is nevertheless, a major restricting factor as streaming multimedia drains battery power quickly. Many battery efficient multimedia adaptation techniques have been proposed that achieve battery efficiency by lowering presentation quality of entire multimedia. Adaptation is usually done without considering any impact on the information contents of multimedia. In this paper, based on the results of an experimental study, we argue that without considering any negative impact on information contents of multimedia the adaptation may negatively impact the learning process. Some portions of the multimedia that require a higher visual quality for conveying learning information may lose their learning effectiveness in the adapted lowered quality. We report results of our experimental study that indicate that different parts of the same learning multimedia do not have same minimum acceptable quality. This strengthens the position that power-saving adaptation techniques for educational multimedia must be developed that lower the quality of multimedia based on the needs of its individual fragments for successfully conveying learning informatio
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Laminar flow-induced scission kinetics of polymers in dilute solutions
AbstractKing Abdulaziz City for Science and Technology (KACST)
EPSRC (Grant No. EP/S009000/1
Mining network-level properties of Twitter altmetrics data
© 2019, AkadĂ©miai KiadĂł, Budapest, Hungary. Social networking sites play a significant role in altmetrics. While 90% of all altmetric mentions come from Twitter, the known microscopic and macroscopic properties of Twitter altmetrics data are limited. In this study, we present a large-scale analysis of Twitter altmetrics data using social network analysis techniques on the âmentionâ network of Twitter users. Exploiting the network-level properties of over 1.4 million tweets, corresponding to 77,757 scholarly articles, this study focuses on the following aspects of Twitter altmetrics data: (a) the influence of organizational accounts; (b) the formation of disciplinary communities; (c) the cross-disciplinary interaction among Twitter users; (d) the network motifs of influential Twitter users; and (e) testing the small-world property. The results show that Twitter-based social media communities have unique characteristics, which may affect social media usage counts either directly or indirectly. Therefore, instead of treating altmetrics data as a black box, the underlying social media networks, which may either inflate or deflate social media usage counts, need further scrutiny
Mechanical circulatory support in patients with severe aortic stenosis and left ventricular dysfunction undergoing percutaneous coronary intervention
Management of obstructive coronary artery disease in patients with aortic stenosis and severe left ventricular dysfunction is challenging. Mechanical circulatory support at the time of percutaneous coronary interventions may be necessary in these extreme-risk patients. We present a case in which the TandemHeart was used to support a patient with severe aortic stenosis, severe protected left main and circumflex disease, and severe cardiomyopathy and review the literature on this subject
First Case Report of Primary Testicular Diffuse Large B-Cell Lymphoma from the Western Region of Saudi Arabia
Primary testicular lymphoma (PTL) represents 1-2% of all types of non-Hodgkin lymphomas (NHLs) and 1-10% of testicular neoplasms. Up to the best of my knowledge, this is the first case of PTL of the diffuse large B-cell lymphoma (DLBCL) in a 60-year-old man presented with a painless mass in the left testis as revealed by physical examination in a tertiary care hospital in Al-Madinah Al-Munwarah in the western region of the Kingdom of Saudi Arabia (KSA). Radiological examination revealed a large well-defined heterogeneous predominantly hypo-echoic mass with increased vascularity in the upper portion of the testis. On the other hand, histopathological examination revealed a tumor involving the whole left testis, which was large (measuring 6 3.5 3.3 cm), solid and dark red with focal areas of hemorrhage and epididymal infiltration. Immunohistochemistry showed positivity of leucocyte common antigen (LCA), pan B-cell marker (CD20) and negativity of pan T-cell marker (CD3). Other immunohistochemical markers such as CD10, placental alkaline phosphatase (PLAP), cytokeratin, vimentin, desmin and S100 protein were also negative. However, there was a marked expression of Ki67 and Bcl2 markers. Accordingly, the diagnosis of DLBCL was established. The tumor was classified as stage I according to the Ann Arbor system. The case was treated by orchiectomy followed by prophylactic anthracycline-based chemotherapy and irradiation of the contralateral testis and central nervous system
Re-Evaluating the Classical Falling Body Problem
This paper re-analyzes the falling body problem in three dimensions, taking into account the effect of the Earthâs rotation (ER). Accordingly, the analytic solution of the three-dimensional model is obtained. Since the ER is quite slow, the three coupled differential equations of motion are usually approximated by neglecting all high order terms. Furthermore, the theoretical aspects describing the nature of the falling point in the rotating frame and the original inertial frame are proved. The theoretical and numerical results are illustrated and discussed.The authors would like to thank the referees for their valuable comments and suggestions, which helped to improve the manuscript. Moreover, the first author thanks Prince Sattam bin Abdulaziz University and Deanship of Scientific Research at Prince Sattam bin Abdulaziz University for their continuous support and encouragement.info:eu-repo/semantics/publishedVersio
Sialidase Inhibitors with Different Mechanisms
Sialidases, or neuraminidases, are enzymes that catalyze the hydrolysis of sialic acid (Sia)-containing molecules, mostly removal of the terminal Sia (desialylation). By desialylation, sialidase can modulate the functionality of the target compound and is thus often involved in biological pathways. Inhibition of sialidases with inhibitors is an important approach for under-standing sialidase function and the underlying mechanisms and could serve as a therapeutic approach as well. Transition-state analogues, such as anti-influenza drugs oseltamivir and zanamivir, are major sialidase inhibitors. In addition, difluoro-sialic acids were developed as mechanism-based sialidase inhibitors. Further, fluorinated quinone methide-based suicide substrates were reported. Sialidase product analogue inhibitors were also explored. Finally, natural products have shown competitive inhibiton against viral, bacterial, and human sialidases. This Perspective describes sialidase inhibitors with different mechanisms and their activities and future potential, which include transition-state analogue inhibitors, mechanism-based inhibitors, suicide substrate inhibitors, product analogue inhibitors, and natural product inhibitors
Myxovirus resistance 1 (MX1) is an independent predictor of poor outcome in invasive breast cancer
Background: Breast cancer (BC) is a disease with variable morphology, clinical behaviour and response to therapy. Identifying factors associated with the progression of early stage BC can help understand the risk of metastasis and guide treatment decisions. Myxovirus resistance 1 (MX1), which is involved in the cellular antiviral mechanism, plays a role in some solid tumours; however, its role in invasive BC remains unknown. In this study, we aimed to explore the clinicopathological and prognostic significance of MX1 in BC.Methods: MX1 was assessed at the protein level using tissue microarrays from a large well-annotated BC cohort (n=845). The expression of MX1 mRNA was assessed at the transcriptomic level using the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC; n=1980) and validated using three publicly available cohorts on Breast Cancer Gene-Expression Miner (bc-GenExMiner version 4.4). The associations between MX1 expression and clinicopathological factors, and outcome were evaluated.Results: High MX1 protein expression was associated with features of aggressiveness, including large tumour size, high tumour grade, high Nottingham prognostic index scores, hormone receptor negativity and high Ki67 expression. High MX1 expression showed an association with poor patient outcome and it was an independent predictor of short BC- specific survival (p=0.028; HR=1.5; 95%CI=1.0â2.2). Consistent with the protein results, high MX1 mRNA levels showed an association with features of aggressive behaviour and with shorter survival.Conclusion: This study identified MX1 as an independent predictor of poor outcome in patients with BC. Further functional studies are needed to investigate the biological role of MX1 in BC and its potential value as a therapeutic target
Sex Differences in the Utilization and Outcomes of Surgical Aortic Valve Replacement for Severe Aortic Stenosis
Background
Studies assessing the differential impact of sex on outcomes of aortic valve replacement (AVR) yielded conflicting results. We sought to investigate sexârelated differences in AVR utilization, patient risk profile, and inâhospital outcomes using the Nationwide Inpatient Sample. Methods and Results
In total, 166 809 patients (63% male and 37% female) who underwent AVR between 2003 and 2014 were identified, and 48.5% had a concomitant cardiac surgery procedure. Compared with men, women were older and had more nonatherosclerotic comorbid conditions including hypertension, diabetes mellitus, obstructive pulmonary disease, atrial fibrillation/flutter, and anemia but fewer incidences of coronary and peripheral arterial disease and prior sternotomies. Inâhospital mortality was significantly higher in women (5.6% versus 4%, P\u3c0.001). Propensity matching was performed to assess the impact of sex on the outcomes of isolated AVR and yielded 28 237 matched pairs of male and female participants. In the propensityâmatched groups, inâhospital mortality was higher in women (3.3% versus 2.9%, P\u3c0.001). Along with vascular complications and blood transfusion (6% versus 5.6%, P=0.027 and 40.4% versus 33.9%, P\u3c0.001, respectively). Rates of stroke, permanent pacemaker implantation, and acute kidney injury requiring dialysis were similar (2.4% versus 2.4%, P=0.99; 6% versus 6.3%, P=0.15; and 1.4% versus 1.3%, P=0.14, respectively). Length of stay median and interquartile range were both similar between groups (7±6 days). Rates of nonhome discharge were higher among women (27.9% versus 19.6%, P\u3c0.001). Conclusions
Women have worse inâhospital mortality following AVR compared with men. Coupled with the accumulating evidence suggesting higher magnitude of benefit of transcatheter AVR over AVRin women, women should perhaps be offered transcatheter AVR over AVR at a lower threshold than men
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