Miracle-dz/UniFAR-FTUs huggingface dataset:
Quality Evaluation of Educational Websites Using Heuristic and Laboratory Methods

Performing quality evaluation of a website, targets to draw certain conclusions, in order to determine if and in which degree the evaluated website features the required usability, measuring at the same time the users’ subjective satisfaction. In this paper we examine the evaluation of the new version of the Hellenic Open University (HOU) website. Among a variety of alternative evaluation approaches, we chose to apply the methods of heuristic evaluation and performance measurement that have been used in generic-type software. The evaluation was performed at the Software Quality Laboratory of the Hellenic Open University, in collaboration with experts in assessing software quality and usability (members of the Software Quality Research Group) as well as regular users (students of the HOU), aiming to draw parallel conclusions and to compare the derived results. The combination of these two evaluation methods revealed users’ non satisfaction and also usability problems that had not been traced in the website’s developing phase. We indicate that, by correcting these detected deficiencies, the website can evolve to become effective, efficient, and handy, providing personal satisfaction to its users.
Man-machine interface and control of the shuttle digital flight system

The space shuttle main engine (SSME) presented new requirements in the design of controls for large pump fed liquid rocket engine systems. These requirements were the need for built in full mission support capability, and complexity and flexibility of function not previously needed in this type of application. An engine mounted programmable digital control system was developed to meet these requirements. The engine system and controller and their function are described. Design challenges encountered during the course of development included accommodation for a very severe engine environment, the implementation of redundancy and redundancy management to provide fail operational/fail safe capability, removal of heat from the package, and significant constraints on computer memory size and processing time. The flexibility offered by programmable control reshaped the approach to engine design and development and set the pattern for future controls development in these types of applications.
Learning to modulate one's own brain activity: the effect of spontaneous mental strategies

Using neurofeedback (NF), individuals can learn to modulate their own brain activity, in most cases electroencephalographic (EEG) rhythms. Although a large body of literature reports positive effects of NF training on behavior and cognitive functions, there are hardly any reports on how participants can successfully learn to gain control over their own brain activity. About one third of people fail to gain significant control over their brain signals even after repeated training sessions. The reasons for this failure are still largely unknown. In this context, we investigated the effects of spontaneous mental strategies on NF performance. Twenty healthy participants performed either a SMR (sensorimotor rhythm, 12–15 Hz) based or a Gamma (40–43 Hz) based NF training over ten sessions. After the first and the last training session, they were asked to write down which mental strategy they have used for self-regulating their EEG. After the first session, all participants reported the use of various types of mental strategies such as visual strategies, concentration, or relaxation. After the last NF training session, four participants of the SMR group reported to employ no specific strategy. These four participants showed linear improvements in NF performance over the ten training sessions. In contrast, participants still reporting the use of specific mental strategies in the last NF session showed no changes in SMR based NF performance over the ten sessions. This effect could not be observed in the Gamma group. The Gamma group showed no prominent changes in Gamma power over the NF training sessions, regardless of the mental strategies used. These results indicate that successful SMR based NF performance is associated with implicit learning mechanisms. Participants stating vivid reports on strategies to control their SMR probably overload cognitive resources, which might be counterproductive in terms of increasing SMR power.
Toxic Epidermal Necrolysis: A Step Forward in Treatment

Toxic epidermal necrolysis is an uncommon but severe form of epidermal sloughing with associated mucositis. Treated in a general hospital, it carries a high mortality (25% to 70%) and substantial long-term morbidity. If the patient is referred early to a burn center, where it can be treated with biologic dressings and intensive support care, the mortality can be reduced below 20% and there may be negligible long-term morbidity. We describe 19 patients so treated, with three deaths and no long-term complications. ( JAMA 1987;257:2171-2175)
A 0.7-MHz–10-MHz  ${\rm CT}+{\rm DT}$ Hybrid Baseband Chain With Improved Passband Flatness for LTE Application

A hybrid baseband chain for Long-Term Evolution (LTE) was implemented in a TSMC 65-nm CMOS process. It has an active area of 0.75 mm2 and a power consumption of 10.8 mW at a supply of 1.8 V. The proposed baseband chain consists of a continuous-time (CT) lowpass filter and a charge-domain discrete-time (DT) filter with a variable gain amplifier (VGA) and a DC-offset canceller (DCOC). The passband distortion of the DT filter is calibrated by varying the quality (Q)-factor of the CT filter, which is easily tuned by switched-resistors. The charge-domain DT filter is adopted for anti-aliasing filtering and efficient interferer rejection with small size and low power consumption. By combining the CT and the DT filters, the baseband chain acquires improved passband flatness with an in-band ripple of less than 1 dB from 0.7 MHz to 10 MHz. It also has a gain of 50.8 dB, input-referred noise of 22.8 nV/√Hz, and an out-of-band IIP3 of 29 dBm.
Transvenous closure of moderate and large secundum atrial septal defects in adults using the Amplatzer septal occluder

The aim was to determine the feasibility of using the Amplatzer septal occluder for closure of moderate and large secundum atrial septal defects in adults. Fifty patients aged 16–76 years (mean ± SD, 40 ± 15.5), underwent successful device implantation. Flow ratios of 1.4–8.5 (mean ± SD, 2.6 ± 1.6) were calculated. The defects were: centrally placed (n = 31), antero‐superior with partial or total deficiency of aortic rim (n = 19), multiple (n = 3) and with aneurysmal septum (n = 23). They measured 4–25 mm (median 14) on echocardiography and balloon sized 7–31 mm (median 19.5). Devices of 7–34 mm (median 20) were implanted. Patient follow up for 1 month (50/50 patients), 3 months (40/50) and 12 months (13/50), achieved respective rates of 90%, 92% and 98% of complete occlusion. In one patient a transient atrioventricular block (2:1) developed, and one had a transient STT elevation. One female had an episode of 30 min loss of vision over the lateral aspect of the left eye 3 months after implantation. In conclusion, transvenous occlusion of secundum atrial septal defects with the Amplatzer septal occluder in adults is safe, and can be performed without significant complications. Large defects, defects with a very deficient or absent aortic rim, defects with an aneurysmal septum as well as some multiple defects can be closed with an almost 100% early complete occlusion rate. This makes the procedure an alternative to surgery for selected adult patients. Cathet Cardiovasc Intervent 2001;52:188–193. © 2001 Wiley‐Liss, Inc.
A population-based incidence of acute large vessel occlusions and thrombectomy eligible patients indicates significant potential for growth of endovascular stroke therapy in the USA

Background Data on large vessel strokes are important for resource allocation and infrastructure development. Objective To determine an annual incidence of large vessel occlusions (LVOs) and a thrombectomy eligible patient population. Methods All patients with acute ischemic stroke discharged over 3 years from a tertiary-level hospital serving a large geographic area were evaluated for an LVO (M1, internal carotid artery terminus, basilar artery). The incidence of LVO was determined for the hospital's 4-county primary service area (PSA, population 210 000) based on each county's discharges and extrapolated to the US population. ‘Thrombectomy eligibility’ for anterior circulation LVOs was based on time (onset <6 hours) and imaging (Alberta Stroke Program Early CT Score (ASPECTS) ≥6). The number of annual thrombectomy procedures was calculated for Medicare and private payer patients using federally available databases. Results 1157 patients were discharged from the hospital's PSA, of whom 129 (11.1%, 95% CI 9.5% to 13.1%) had an LVO. This translated into an LVO incidence of 24 per 100 000 people per year (95% CI 20 to 28). 20 per 100 000 people per year had anterior circulation LVOs (95% CI 19 to 22), of whom 10/100 000/year (95% CI 8 to 11) were ‘thrombectomy eligible’. An additional 5/100 000/year (95% CI 3 to 6) presented with favorable ASPECTS after 6 hours of symptom onset. Basilar occlusion incidence was estimated at 4/100 000/year (95% CI 2 to 5). These rates yield 77 569 (95% CI 65 835 to 91 091) new LVOs per year in the USA. An estimated 10 284 mechanical thrombectomy procedures were performed in 2015. Conclusions This study estimates an LVO incidence of 24 per 100 000 person-years (95% CI 20 to 28). A current estimated annual thrombectomy rate of three procedures per 100 000 people indicates significant potential increase in the volume of endovascular procedures and the need to develop systems of care.
Epigenetic Regulation of BMP2 by 1,25-dihydroxyvitamin D3 through DNA Methylation and Histone Modification

Genetic hypercalciuric stone-forming (GHS) rats have increased intestinal Ca absorption, decreased renal tubule Ca reabsorption and low bone mass, all of which are mediated at least in part by elevated tissue levels of the vitamin D receptor (VDR). Both 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and bone morphogenetic protein 2 (BMP2) are critical for normal maintenance of bone metabolism and bone formation, respectively. The complex nature of bone cell regulation suggests a potential interaction of these two important regulators in GHS rats. In the present study, BMP2 expression is suppressed by the VDR-1,25(OH)2D3 complex in Bone Marrow Stromal Cells (BMSCs) from GHS and SD rat and in UMR-106 cell line. We used chromatin immunoprecipitation (ChIP) assays to identify VDR binding to only one of several potential binding sites within the BMP2 promoter regions. This negative region also mediates suppressor reporter gene activity. The molecular mechanisms underlying the down-regulation of BMP2 by 1,25(OH)2D3 were studied in vitro in BMSCs and UMR-106 cells using the DNA methyltransferase inhibitor 5-aza-2′-deoxycytidine (DAC) and the histone deacetylase inhibitor trichostatin A (TSA). Both DAC and TSA activate BMP2 expression in combination with 1,25(OH)2D3. Bisulfite DNA pyrosequencing reveals 1,25(OH)2D3 to completely hypermethylate a single CpG site in the same BMP2 promoter region identified by the ChIP and reporter gene assays. ChIP assays also show that 1,25(OH)2D3 can increase the repressive histone mark H3K9me2 and reduce the acetylation of histone H3 at the same BMP2 promoter region. Taken together, our results indicate that 1,25(OH)2D3 binding to VDR down-regulates BMP2 gene expression in BMSCs and osteoblast-like UMR-106 cells by binding to the BMP2 promoter region. The mechanism of this 1,25(OH)2D3-induced transcriptional repression of BMP2 involves DNA methylation and histone modification. The study provides novel evidence that 1,25(OH)2D3 represses bone formation through down-regulating BMP2 expression both in vivo and in vitro.
A growth factor signaling cascade confined to circular ruffles in macrophages

Summary The formation of macropinosomes requires large-scale movements of membranes and the actin cytoskeleton. Over several minutes, actin-rich surface ruffles transform into 1–5 µm diameter circular ruffles, which close at their distal margins, creating endocytic vesicles. Previous studies using fluorescent reporters of phosphoinositides and Rho-family GTPases showed that signals generated by macrophages in response to the growth factor Macrophage Colony-Stimulating Factor (M-CSF) appeared transiently in domains of plasma membrane circumscribed by circular ruffles. To address the question of how signaling molecules are coordinated in such large domains of plasma membrane, this study analyzed the relative timing of growth factor-dependent signals as ruffles transformed into macropinosomes. Fluorescent protein chimeras expressed in macrophages were imaged by microscopy and quantified relative to circular ruffle formation and cup closure. The large size of macropinocytic cups allowed temporal resolution of the transitions in phosphoinositides and associated enzyme activities that organize cup closure. Circular ruffles contained transient and sequential spikes of phosphatidylinositol (4,5)-bisphosphate (PI(4,5)P2), phosphatidylinositol (3,4,5)-trisphosphate (PIP3), diacylglycerol, PI(3,4)P2, PI(3)P and the activities of protein kinase C-&agr;, Rac1, Ras and Rab5. The confinement of this signal cascade to circular ruffles indicated that diffusion barriers present in these transient structures focus feedback activation and deactivation of essential enzyme activities into restricted domains of plasma membrane.
Bilateral Context Modeling for Residual Coding in Lossless 3D Medical Image Compression

Residual coding has gained prevalence in lossless compression, where a lossy layer is initially employed and the reconstruction errors (i.e., residues) are then losslessly compressed. The underlying principle of the residual coding revolves around the exploration of priors based on context modeling. Herein, we propose a residual coding framework for 3D medical images, involving the off-the-shelf video codec as the lossy layer and a Bilateral Context Modeling based Network (BCM-Net) as the residual layer. The BCM-Net is proposed to achieve efficient lossless compression of residues through exploring intra-slice and inter-slice bilateral contexts. In particular, a symmetry-based intra-slice context extraction (SICE) module is proposed to mine bilateral intra-slice correlations rooted in the inherent anatomical symmetry of 3D medical images. Moreover, a bi-directional inter-slice context extraction (BICE) module is designed to explore bilateral inter-slice correlations from bi-directional references, thereby yielding representative inter-slice context. Experiments on popular 3D medical image datasets demonstrate that the proposed method can outperform existing state-of-the-art methods owing to efficient redundancy reduction. Our code will be available on GitHub for future research.
Plasma Transglutaminase in Hypertrophic Chondrocytes: Expression and Cell-specific Intracellular Activation Produce Cell Death and Externalization

We previously used subtractive hybridization to isolate cDNAs for genes upregulated in chick hypertrophic chondrocytes (Nurminskaya, M., and T.F. Linsenmayer. 1996. Dev. Dyn. 206:260–271). Certain of these showed homology with the “A” subunit of human plasma transglutaminase (factor XIIIA), a member of a family of enzymes that cross-link a variety of intracellular and matrix molecules. We now have isolated a full-length cDNA for this molecule, and confirmed that it is avian factor XIIIA. Northern and enzymatic analyses confirm that the molecule is upregulated in hypertrophic chondrocytes (as much as eightfold). The enzymatic analyses also show that appreciable transglutaminase activity in the hypertrophic zone becomes externalized into the extracellular matrix. This externalization most likely is effected by cell death and subsequent lysis—effected by the transglutaminase itself. When hypertrophic chondrocytes are transfected with a cDNA construct encoding the zymogen of factor XIIIA, the cells convert the translated protein to a lower molecular weight form, and they initiate cell death, become permeable to macromolecules and eventually undergo lysis. Non-hypertrophic cells transfected with the same construct do not show these degenerative changes. These results suggest that hypertrophic chondrocytes have a novel, tissue-specific cascade of mechanisms that upregulate the synthesis of plasma transglutaminase and activate its zymogen. This produces autocatalytic cell death, externalization of the enzyme, and presumably cross-linking of components within the hypertrophic matrix. These changes may in turn regulate the removal and/or calcification of this hypertrophic matrix, which are its ultimate fates.
Outward Currents Contributing to Inspiratory Burst Termination in preBötzinger Complex Neurons of Neonatal Mice Studied in Vitro

We studied preBötzinger Complex (preBötC) inspiratory interneurons to determine the cellular mechanisms that influence burst termination in a mammalian central pattern generator. Neonatal mouse slice preparations that retain preBötC neurons generate respiratory motor rhythms in vitro. Inspiratory-related bursts rely on inward currents that flux Na+, thus outward currents coupled to Na+ accumulation are logical candidates for assisting in, or causing, burst termination. We examined Na+/K+ ATPase electrogenic pump current (Ipump), Na+-dependent K+ current (IK–Na), and ATP-dependent K+ current (IK–ATP). The pharmacological blockade of Ipump, IK–Na, or IK–ATP caused pathological depolarization akin to a burst that cannot terminate, which impeded respiratory rhythm generation and reversibly stopped motor output. By simulating inspiratory bursts with current-step commands in synaptically isolated preBötC neurons, we determined that each current generates approximately 3–8 mV of transient post-burst hyperpolarization that decays in 50–1600 ms. Ipump, IK–Na, and – to a lesser extent – IK–ATP contribute to terminating inspiratory bursts in the context of respiratory rhythm generation by responding to activity dependent cues such as Na+ accumulation.
Design of linear dispersion codes: asymptotic guidelines and their implementation

In this paper, a design method is developed for the class of linear-dispersion (LD) codes - a diverse set of space-time codes that subsumes several standard designs. The development begins by showing that for systems that employ a large number of transmit antennas, LD codes constructed from unitary coding matrices are asymptotically optimum from different design perspectives, viz., minimum mean square error (MMSE), mutual information, and average pairwise error probability (PEP). Those measures have a direct impact on the detection complexity, data rate, and error performance that a space-time code can achieve. Using the insight generated by the asymptotic result, a structured design technique for the LD coding matrices, that suits a broad class of configurations is provided. The resulting codes can support high data rates and provide performance advantages over current designs when decoded with a standard detector. Based on the asymptotic results, a row interleaving scheme is proposed, and it is shown to result in significant performance enhancement.
Incomplete Mitral Leaflet Closure in Patients with Papillary Muscle Dysfunction

Clinical acceptance of an association between papillary muscle dysfunction and mitral regurgitation is widespread, despite the lack of objective support. To evaluate a possible association, we performed echocardiographic examinations on 22 patients with prior myocardial infarction and clinical evidence of papillary muscle dysfunction, 40 patients with prior myocardial infarction and no clinical evidence of papillary muscle dysfunction, and 20 normal subjects. There was a unique pattern of incomplete mitral leaflet closure ina high percentage (91%) of infarct patients with mitral regurgitation. In these patients, one or both leaflets we3e effectively arrested within the cavity of the left ventricle during ventricular systole. Dyskinetic wall motion in the region immediately surrounding one of the papillary muscles was present in 23 of 24 patients (96%) with demonstrated incomplete closure. This study provides the first objective evidence that de novo mitral regurgitation in patients with prior myocardial infarction is due to dyskinesis involving the left ventricular myocardium beneath one of the papillary muscles, producing increased tension on the mitral leaflets and preventing normal closure.
In vitro anti‐Trichomonas gallinae effects of Ziziphus vulgaris L. and Camellia sinensis (L.) Kuntze extracts

Abstract Background Trichomonas gallinae is a parasite that causes canker and severe loss and death, especially in young pigeons. Metronidazole (MTZ) is the recommended drug for treating avian trichomoniasis. Due to drug resistance, non‐chemical alternatives, such as medicinal plant extracts, are also considered possible therapies for this disease. Objectives This study compares the antitrichomonal effects of MTZ with extracts of Camellia sinensis and Ziziphus vulgaris on T. gallinae in vitro. Methods Samples of T. gallinae were taken from infected pigeons. Multi‐well plates with different concentrations (5, 10, 25, 50 and 100 µg/mL) of plant extracts were used for the in vitro study. Results The minimum inhibitory concentration (MIC) of C. sinensis extract was 25 µg/mL over 24 h, compared to 50 µg/mL for MTZ. The MIC value of the Z. vulgaris extracts was 50 µg/mL. Conclusions The results suggest that the extracts of Z. vulgaris and C. sinensis, as potential natural agents, could have anti‐avian trichomoniasis properties. This study also shows that MTZ, C. sinensis and Z. vulgaris are equally effective in preventing the growth of T. gallinae trophozoites in the culture.
Advanced Glycation End Products Induce Endothelial-to-Mesenchymal Transition via Downregulating Sirt 1 and Upregulating TGF-β in Human Endothelial Cells

In the present study, we examined the advanced glycation end products- (AGEs-) induced endothelial-to-mesenchymal transition (EndMT) in human umbilical vein endothelial cells (HUVECs). Results demonstrated that AGE-BSAs significantly reduced the cluster of differentiation 31 (CD 31) expression, whereas they promoted the expression of fibroblast-specific protein-1 (FSP-1), α-smooth muscle antibody (α-SMA), and collagen I at both mRNA and protein levels in HUVECs. And the AGE-BSAs also promoted the receptors for AGEs (RAGEs) and receptor I for TGF-β (TGFR I) markedly with a dose dependence, whereas the Sirt 1 was significantly downregulated by the AGE-BSA at both mRNA and protein levels. Moreover, the Sirt 1 activity manipulation with its activator, resveratrol (RSV), or its inhibitor, EX527, markedly inhibited or ameliorated the AGE-mediated TGF-β upregulation. And the manipulated Sirt 1 activity positively regulated the AGE-induced CD31, whereas it negatively regulated the AGE-induced FSP-1. Thus, Sirt 1 was confirmed to regulate the AGE-induced EndMT via TGF-β. In summary, we found that AGE-BSA induced EndMT in HUVECs via upregulating TGF-β and downregulating Sirt 1, which also negatively regulated TGF-β in the cell. This study implied the EndMT probably as an important mechanism of AGE-induced cardiovascular injury.