Intelligent E-Learning System with Personalized Misconception Diagnose and Learning Path Guidance

In recent years, to advances network technology, IT-enabled learning and support learning are important in on-line education. More learners obtain knowledge by the Web-Learning Instruction (WBI). Learners usually induce the problem of misconception and cognitive overload when they use Web-based learning system. At present, most of the studies in the on-line education either concentrate on the technological aspect (e.g. personalization technology development) or focus on adapting learner’s interests or browsing behaviors, while, learner’s ability and level of knowledge is neglected. Therefore, it is important to consider learner’s ability while designing web-based learning system. This study developed an On-line Knowledge Diagnose System (OKDS) to diagnose learner’s misconception and provide personalized remedial guidance that based on a graphic organizer technology - concept map. The results indicate that the OKDS can effectiveness enhance learners learner’s learning performance and learner also has positive perception of OKDS

MicroRNA in Diabetic and TGFbeta-Related Renal Glomerulopathy.

Chronic kidney disease (CKD) decreases quality of life, increases mortality, and has limited treatment options. Glomerular injury is an early stage of diabetic nephropathy (DN), which is a leading cause of CKD, and is characterized by mesangial cell proliferation and hypertrophy, loss of podocytes, and increased extracellular matrix (ECM) deposition. Critical aspects of these cellular events are mediated by activation of the Transforming Growth Factor-beta (TGFβ) signaling cascade. MicroRNAs (miRNAs) regulate gene expression in a post-transcriptional level and have been implicated as important regulatory elements in the TGFβ signaling cascade. To determine the role of miRNAs in DN, we examined miRNA expression in micro-dissected glomeruli from kidney biopsies of patients with clinically early DN and correlated the expression levels with clinical manifestations. We determined that miR-21 exhibits high expression in renal glomeruli and significant correlation with urine albumin-to-creatinine-ratio (ACR) of patients. miR-21 is a known regulator of TGFβ signaling and its level is positively associated with severity of renal phenotype in TGFβ transgenic mice. We further found that loss of miR-21 in TGFβ transgenic mice resulted in accelerated podocyte apoptosis and glomerulosclerosis. A similar phenotype was detected in streptozotocin-induced diabetic mice. In cultured glomerular cells, loss or inhibition of miR-21 led to increased apoptosis of podocytes and increased proliferation of primary mesangial cells. Further studies showed that miR-21 represses multiple pro-apoptotic pathways, including TGFβ/Smad7, P53, and PDCD4, cell cycle-related genes such as Cdk6 and Cdc25a, and ECM-related genes. These results suggest that miR-21 ameliorates glomerular injury through repression of multiple injury-mediating signaling pathways. To further elucidate a miRNA-mediated network mediating DN progression, we examined mRNA expression in the same glomerular samples. We identified ACR-associated genes that are predicted targets of ACR-associated miRNAs and experimentally validated the sequence-dependent repression of candidate target genes of miR-200a. This led to the discovery of EXOC7 as a sequence-dependent target of miR-200a. In summary, correlating miRNA expression with specific clinical outcomes identified novel mechanisms regulating DN, including a protective role for miR-21 in glomerular injury. Furthermore, the approach, which links disease-associated miRNAs and mRNAs by target prediction, appears to facilitate identification of context-relevant miRNA-mRNA interactions.PHDCellular & Molecular BiologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/100077/1/chunlai_1.pd

Endoscopic dacryocystorhinostomy with short-term, pushed-type bicanalicular intubation vs. pulled-type monocanalicular intubation for primary acquired nasolacrimal duct obstruction

Dacryocystorhinostomy (DCR) has been a primary treatment for adults with nasolacrimal duct obstruction, while the optimal approach and technique remain controversial. With the advancement of endoscopic DCR and the silicone stents, an update of the surgical outcomes and preferable approaches is required. This study aims at comparing the surgical outcomes of endoscopic DCR using pushed bicanalicular intubation (BCI) to pulled monocanalicular intubation (MCI) in adults with primary acquired nasolacrimal duct obstruction (PANDO). Forty five eyes of 45 patients were enrolled, including 22 eyes of 22 patients treated with endoscopic DCR with pulled MCI and 23 eyes of 23 patients with pushed BCI from January 2014 to June 2021. The success rates at stent removal, 1 month and 3 months after removal were 95, 91, and 82%, respectively, in the MCI group, and 100, 87, and 87% in the BCI group. The BCI group had better success rates but failed to reach a significant difference (p = 0.49, p = 0.67, p = 0.24, respectively). After analyzing with binary logistic regression, the implant material was demonstrated as the predictive of surgical success (p = 0.045). There was no significant difference in success rates between patients with dacryocystitis and those without dacryocystitis. We conclude that endoscopic DCR with pushed BCI is easily manipulated and has a promising surgical outcome over pulled MCI. Stent indwelling duration as well as history of dacryocystitis have less influence on the success rates

Deferoxamine retinopathy: spectral domain-optical coherence tomography findings

Al-Djamiʿ li Ibn al-BaïtharNumérisation effectuée à partir d'un document de substitution

Deferoxamine retinopathy: spectral domain-optical coherence tomography findings

BACKGROUND: To describe the spectral domain optical coherence tomography (SD-OCT) findings of a patient who developed pigmentary retinopathy following high-dose deferoxamine administration. CASE PRESENTATION: A 34-year-old man with thalassemia major complained of nyctalopia and decreased vision following high-dose intravenous deferoxamine to treat systemic iron overload. Fundus examination revealed multiple discrete hypo-pigmented lesions at the posterior pole and mid-peripheral retina. Recovery was partial following cessation of desferrioxamine six weeks later. A follow-up SD-OCT showed multiple accumulated hyper-reflective deposits primarily in the choroid, retina pigment epithelium (RPE), and inner segment and outer segment (IS/OS) junction. CONCLUSION: Deferoxamine retinopathy primarily targets the RPE–Bruch membrane–photoreceptor complex, extending from the peri-fovea to the peripheral retina with foveola sparing. An SD-OCT examination can serve as a simple, noninvasive tool for early detection and long-term follow-up

The Chitinolytic Activities of Streptomyces sp. TH-11

Chitin is an abundant biopolymer composed of units of N-acetyl-D-glucosamine linked by β-1,4 glycosidic bonds. Chitin is the main component of the shells of mollusks, the cell wall of fungi and yeast and of the exoskeleton of crustaceans and insects. The degradation of chitin is catalyzed by chitinases that occur in a wide range of organisms. Among them, the chitinases from microorganisms are extremely important for the degradation and recycling of the carbon and nitrogen trapped in the large amount of insoluble chitin in nature. Streptomyces sp. TH-11 was isolated from the sediment of the Tou-Chien River, Taiwan. The chitinolytic enzyme activities were detected using a rapid in-gel detection method from the cell-free preparation of the culture medium of TH-11. The chitinolytic enzyme activity during prolonged liquid culturing was also analyzed by direct measurement of the chitin consumption. Decomposition of the exoskeleton of shrimps was demonstrated using electron microscopy and atomic force microscopy

Electrochemical Oxidation of Fragrances 4-Allyl and 4-Propenylbenzenes on Platinum and Carbon Paste Electrodes

The electrochemical oxidation behaviors of 4-allylbenzenes (estragole, safrole and eugenol) and 4-propenylbenzenes (anethole, asarone and isoeugenol) on platinum and carbon paste electrodes were investigated in a Britton-Robinson buffer (pH = 2.93 and 10.93), acetate buffer, phosphate buffer solutions (pH = 2.19 and 6.67), and acetonitrile containing various supporting electrolytes examined lithium perchlorate. Their oxidation potential with Hammett (free-energy relationships) and possible reaction mechanisms were discussed

Cadmium burden and the risk and phenotype of prostate cancer

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