13 research outputs found

    A Practical and Empirical Comparison of Three Topic Modeling Methods Using a COVID-19 Corpus: LSA, LDA, and Top2Vec

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    This study was prepared as a practical guide for researchers interested in using topic modeling methodologies. This study is specially designed for those with difficulty determining which methodology to use. Many topic modeling methods have been developed since the 1980s namely, latent semantic indexing or analysis (LSI/LSA), probabilistic LSI/LSA (pLSI/pLSA), naïve Bayes, the Author-Recipient-Topic (ART), Latent Dirichlet Allocation (LDA), Topic Over Time (TOT), Dynamic Topic Models (DTM), Word2Vec, Top2Vec, and \variation and combination of these techniques. Researchers from disciplines other than computer science may find it challenging to select a topic modeling methodology. We compared a recently developed topic modeling algorithm Top2Vec with two of the most conventional and frequently-used methodologiesLSA and LDA. As a study sample, we used a corpus of 65,292 COVID-19-focused abstracts. Among the 11 topics we identified in each methodology, we found high levels of correlation between LDA and Top2Vec results, followed by LSA and LDA and Top2Vec and LSA. We also provided information on computational resources we used to perform the analyses and provided practical guidelines and recommendations for researchers

    A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

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    The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

    One step effective removal of Congo Red in chitosan nanoparticles by encapsulation

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    WOS: 000385601300016PubMed: 27501485Chitosan nanoparticles (CNPs) were prepared with ionotropic gelation between chitosan and tripolyphosphate for the removal of Congo Red. The production of chitosan nanoparticles and the dye removal process was carried out in one-step. The removal efficiency of Congo Red by encapsulation within chitosan from the aqueous solution and its storage stability are examined at different pH values. The influence of some parameters such as the initial dye concentration, pH value of the dye solution, electrolyte concentration, tripolyphosphate concentration, mixing time and speed on the encapsulation is examined. Congo Red removal efficiency and encapsulation capacity of chitosan nanoparticles were determined as above 98% and 5107 mg Congo Red/g chitosan, respectively. (C) 2016 Elsevier B.V. All rights reserved.Hitit UniversityHitit University [MUH19002.15.002]This work was supported by the Research Fund of the Hitit University (MUH19002.15.002)

    Asymptomatic intracranial hemorrhage in a newborn with congenital factor VII deficiency and successful treatment with recombinant activated factor VII.

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    Intracranial hemorrhage is considered the most common cause of death in newborns with congenital factor VII (FVII) deficiency. Recombinant activated FVII (rFVIIa) provides specific replacement therapy, however there is limited experience with its neonatal use. We describe our experience about the treatment of intracranial hemorrhage in a newborn with congenital FVII deficiency and emphasize the importance of imaging in asymptomatic patients. She presented with ecchymoses on her skin, no other pathological clinical signs, prolonged PT, normal PTT and FVII activity of 2%. Intracranial hemorrhage was diagnosed while screening for internal bleedings. Treatment with rFVIIa resulted in stabilization and regression of the hematoma

    Phenolic compounds, carotenoids, and antioxidant capacities of a thermo-tolerant Scenedesmus sp. (Chlorophyta) extracted with different solvents

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    The human body can fight against the adverse effects of chronic exposure to environmental pollutants and stress by consumption of a diet rich in antioxidants. Although fruits and vegetables are the predominant sources, alternative sources of antioxidants such as microalgae are also being explored. Here, we investigate the antioxidant capacity, total phenolic, flavonoid, and carotenoid contents of novel thermo-resistant green microalga Scenedesmus sp. ME02. This strain has previously been shown to have a high polyunsaturated fatty acid content. Four different solvents were used for extraction and the antioxidant capacity was determined to be 3.71 +/- 0.11 and 47.01 +/- 3.14molTroloxeq.g(-1)DW in ethanol/water mixture by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays, respectively. Total phenolic, flavonoid, and carotenoid contents in ethanol/water were measured as 5.40 +/- 0.28mggallic acideq.g(-1)DW, 1.61 +/- 0.76mgquercetineq.g(-1)DW, 0.61 +/- 0.05mgg(-1), respectively. This is one of the few studies that reports the presence and quantification of total flavonoids in microalgae. The correlation between the total phenolic content and FRAP assay, but not the DPPH assay, was statistically significant. Finally, 12 different phenolic compounds were analyzed by reverse-phase HPLC and ethyl acetate extract showed substantial amounts of quercetin (0.84 +/- 0.12mgg(-1)DW) and rutin (0.11 +/- 0.08mgg(-1)DW). Quercetin amount was also high in the ethanol/water extract along with gallic acid, 4-hydroxy benzoic acid, and chlorogenic acid. To the best of our knowledge, this is the first study that reports significant amounts of quercetin and rutin in a microalgal species

    Histopathological evaluation of the effects of thymoquinone and resveratrol on the liver in rats administered doxorubicin

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    Aim:&nbsp;The purpose was to investigate the effects of various dosages of thymoquinone and resveratrol (5 and 20 mg/kg) on doxorubicin-induced hepatotoxicity in rats from a pathological standpoint.Materials and Methods:&nbsp;Eighty male Wistar Albino rats were used in this study. Animals were divided in to 10 groups: Control (physiological saline, PO); Doxorubicin (physiological saline, PO and Dox,15mg/kg Dox in 10th days, IP); Thymoquinone -5 (TQ-5, 5 mg/kg TQ, PO); TQ-20 (20 mg/ kg TQ, PO); Resveratrol-5 (Res-5, 5 mg/kg Res, PO); Res-20 (20 mg/kg Res, PO); Dox+TQ-5 ; Dox+TQ-20; Dox+Res-5; Dox+Res-20. After the 21-day experiment, 6 replicates were randomly selected from the groups. After weighing the body weight, the livers of the euthanized rats were dissected and weighed. Routine tissue processing processes were applied to liver samples. Hepatocyte degeneration, necrosis/apoptosis, bile duct hyperplasia, dissociation, congestion, karyomegaly, mononuclear cell infiltration, binuclear hepatocytes, and mitosis were all examined microscopically, and a liver total lesion score was calculatedResults:&nbsp;Dox treatment increased relative liver weight, but the TQ and Res groups prevented this increase (p&lt;0.05). The liver total lesion score, which increased with Dox, was shown to be lower in the TQ and Res groups (p&lt;0.05). However, the Dox+TQ-5, Dox+TQ-20, and Dox+Res-20 groups, showed no amelioration in necrosis/apoptosis.Conclusion:&nbsp;TQ and Res (5 and 20 mg/kg) decreased the total liver lesion score induced by Dox. Although TQ and RES diminish degeneration and inflammation, their poor protective effects on necrosis/apoptosis, one of the key criteria, were considered as a limiting cause for their uncontrolled usage.</p

    Coexistence of Obstructive Sleep Apnea Syndrome and Narcolepsy: Four Cases

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    Excessive daytime sleepiness is a common clinical application of Obstructive Sleep Apnea syndrome and narcolepsy patients. Although both medical conditions can be different in extensive daytime sleepiness features and accompanying symptomatology, distinctive features may be masked in some cases. In our four reported cases, there were obstructive sleep apnea syndrome and narcolepsy type 1 coexistence. We aimed to discuss the possibility of this condition being comorbidity, the possibility of masking the type clinics in their association or the possibility of causing each other's risk factors

    Evaluation of the Carbapenem Inactivation Method for Detection of Carbapenemase-Producing Gram-Negative Bacteria in Comparison with the RAPIDEC CARBA NP

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    SANDALLI, Cemal/0000-0002-1298-3687; aktas, elif/0000-0003-3087-5425WOS: 000402567800007PubMed: 27575912Timely detection of carbapenemases by both phenotypic and genotypic methods is essential for developing strategies to control the spread of infections by carbapenem-resistant isolates and related morbidity and mortality. the aim of this study was to compare the performance of a commercial kit, the RAPIDEC (R) CARBA NP, and an in-house technique, the carbapenem inactivation method (CIM), against a panel of 136 carbapenemase and noncarbapenemase-producing Enterobacteriaceae, Acinetobacter baumannii, and Pseudomonas aeruginosa isolates. RAPIDEC CARBA NP displayed 99% sensitivity and 100% specificity, whereas the sensitivity and specificity were 78% and 100% for the CIM test, respectively. A slight modification of the CIM test, a prolonged incubation time of 4 hours instead of two, increased the sensitivity of the test to 90% by diminishing false negativity particularly for A. baumannii. in conclusion, both tests possess a high performance and are practical for the detection of carbapenemases. Although RAPIDEC CARBA NP is a more rapid and reliable method, the CIM test may represent a useful tool for microbiology laboratories due to its simplicity and availability at any laboratory with low cost.Sisli Hamidiye Etfal Training and Research HospitalThis work was supported by internal funding of Sisli Hamidiye Etfal Training and Research Hospital (decision date: July 12, 2015)
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