207 research outputs found
Headspace solid-phase microextraction and gas chromatography–mass spectrometry of volatile components of Chrysanthemum morifolium Ramat
Purpose: To extract and analyze the volatile components of Chrysanthemum morifolium Ramat. 'huaiju' by headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry (GC–MS).Methods: Volatile components were extracted by HS-SPME and identified by GC–MS. The relative contents of the components were determined by area normalization.Results: The enhanced SPME conditions of C. morifolium involved sample extraction using a 65 μm polydimethylsiloxane/divinylbenzene extraction fiber after balancing for 40 min at 80 °C. A total of 48 components of the essential oil were identified. The major constituents are 2,6,6-trimethylbicyclo[3.1.1]hept-2-en-4-ol, acetate (15.90 %), 4,6,6-trimethyl-bicyclo[3.1.1]hept-3-en-2-one (14.86 %), 2,7,7-trimethyl-bicyclo[3.1.1]hept-2-en-6-one (13.08 %), and cyclohexene,3-(1,5-dimethyl-4-hexenyl)-6- methylene (5.97 %).Conclusion: HS-SPME and GC–MS are convenient, rapid, and reliable approaches for analyzing the volatile components of C. morifolium.Keywords: Chrysanthemum morifolium Ramat., Headspace Solid-phase Microextraction, Gas Chromatography–Mass Spectrometry, Volatile componen
Multi-level Extensible Synthetic Evaluation of the Quality of Passenger Transport Service of High-speed Rail
Abstract: This study establishes the evaluation index system of the quality of passenger transport service of highspeed rail based on the characteristics of passenger transport and determines the index weights with the Fuzzy Analytic Hierarchy Process. In order to make up for the deficiencies of present quality evaluation method of passenger transport service of high-speed rail, this study develops the multi-level extensible synthetic evaluation model of the quality of passenger transport service of high-speed rail with the core of extension method based on the questionnaire survey to the passengers. This study tests the model with the data surveyed in a passenger station of high-speed rail, which can not only expand extension application areas, but also provide new ideas and means for the evaluation of the quality of passenger transport service of high-speed rail
The REST Gene Signature Predicts Drug Sensitivity in Neuroblastoma Cell Lines and Is Significantly Associated with Neuroblastoma Tumor Stage
Neuroblastoma is the most common and deadly solid tumor in children, and there is currently no effective treatment available for neuroblastoma patients. The repressor element-1 silencing transcription (REST) factor has been found to play important roles in the regulation of neural differentiation and tumorigenesis. Recently, a REST signature consisting of downstream targets of REST has been reported to have clinical relevance in both breast cancer and glioblastoma. However it remains unclear how the REST signature works in neuroblastoma. Publicly available datasets were mined and bioinformatic approaches were used to investigate the utility of the REST signature in neuroblastoma with both preclinical and real patient data. The REST signature was found to be associated with drug sensitivity in neuroblastoma cell lines. Further, neuroblastoma patients with enhanced REST activity are significantly associated with higher clinical stages. Loss of heterozygosity on chromosome 11q23, which occurs in a large subset of high-risk neuroblastomas, tends to be correlated with high REST activity, with marginal significance. In conclusion, the REST signature has important implications for targeted therapy, and it is a prognostic factor in neuroblastoma patients
Improve Affective Learning with EEG Approach
With the development of computer science, cognitive science and psychology, a new paradigm, affective learning, has emerged into e-learning domain. Although scientists and researchers have achieved fruitful outcomes in exploring the ways of detecting and understanding learners affect, e.g. eyes motion, facial expression etc., it sounds still necessary to deepen the recognition of learners affect in learning procedure with innovative methodologies. Our research focused on using bio-signals based methodology to explore learner's affect and the study was primarily made on Electroencephalography (EEG). After the EEG signals were collected from EEG equipment, we tidied the EEG data with signal processing algorithms and then extracted some features. We applied k-Nearest-Neighbor classifier and Naive Bayes classifier to these features to find out a combination, which may mostly contribute to reflect learners' affect, for example, Attention. In the classification algorithm, we presented a different way of using the Self-Assessment Manikin (SAM) model to classify and analyze learners attention, although the SAM was normally used for classifying emotions, for example, happiness etc. For the purpose of evaluating our findings, we also developed an affective learning prototype based on university e-learning web site. A real time EEG feedback window and an attention report were integrated into the system. The result of the experiment was encouraging and further discussion was also included in this paper
Acupuncture for Chronic Urinary Retention due to Spinal Cord Injury: A Systematic Review
No systematic review has been published on the use of acupuncture for the treatment of chronic urinary retention (CUR) due to spinal cord injury (SCI). The aim of this review was to assess the effectiveness and safety of acupuncture for CUR due to SCI. Three randomized controlled trials (RCTs) including 334 patients with CUR due to SCI were included. Meta-analysis showed that acupuncture plus rehabilitation training was much better than rehabilitation training alone in decreasing postvoid residual (PVR) urine volume (MD −109.44, 95% CI −156.53 to −62.35). Likewise, a combination of acupuncture and aseptic intermittent catheterization was better than aseptic intermittent catheterization alone in improving response rates (RR 1.23, 95% CI 1.10 to 1.38). No severe adverse events were reported. In conclusion, acupuncture as a complementary therapy may have a potential effect in CUR due to SCI in decreasing PVR and improving bladder voiding. Additionally, acupuncture may be safe in treating CUR caused by SCI. However, due to the lack of high quality RCTs, we could not draw any definitive conclusions. More well-designed RCTs are needed to provide strong evidence
- …