54 results on '"Da Dai"'
Search Results
2. Protection Schemes for Plasma Induced Damage from Well-Side Antennas
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Hsi-Yu Kuo, Yu-Lin Chu, Hung-Da Dai, Chun-Chi Wang, Pei-Jung Lin, Ethan Guo, Yu-Ti Su, Chia-Lin Hsu, Kuan-Hung Chen, Tsung-Yuan Chen, Ryan Lu, Victor Liang, Kuo-Ji Chen, and Kejun Xia
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- 2023
3. Upconversion hollow nanospheres CeF3 co-doped with Yb3+ and Tm3+ for photocatalytic nitrogen fixation
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Xiazhang Li, Da Dai, Baozhu Yang, Wu Fengqin, Zhendong Wang, Minghui Zhong, Chao Yao, and Shixiang Zuo
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Materials science ,business.industry ,Heteroatom ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,medicine.disease_cause ,Photochemistry ,Solar energy ,01 natural sciences ,Nitrogen ,Photon upconversion ,0104 chemical sciences ,Catalysis ,Adsorption ,chemistry ,Geochemistry and Petrology ,medicine ,Photocatalysis ,0210 nano-technology ,business ,Ultraviolet - Abstract
Solar driven nitrogen (N2) fixation to synthesize ammonia is a potential alternative for the traditional Haber-Bosch approach to meeting industrial demand, but is largely hampered by the difficulties in the harvesting of solar energy and activating inert N2. In this work, hollow CeF3 nanospheres co-doped with activator Tm3+ and sensitizer Yb3+ (Yb3+:Tm3+:CeF3) were prepared by microwave hydrothermal method. The product was employed as a catalyst for photo-driven N2 fixation by adjusting the molar ratio of Ce3+:Yb3+:Tm3+. Results show that the porous hollow structure enhances the light-harvesting by physical scattering and reflection. In addition, heteroatom doping generates abundant fluorine vacancies (FV) which provide abundant active sites for adsorption and activation of N2. The sample with molar ratio of CeF3:Yb3+:Tm3+ at 178:20:2 demonstrates the highest utilization of solar energy attributed to the strongest upconversion capability of near-infrared (NIR) light to visible and ultraviolet (UV) light, and the NH4+ concentration achieves the highest value of 15.06 μmol/(gcat∙h) under simulated sunlight while nearly 6.22 μmol/(gcat∙h) under NIR light. Current study offers a promising and sustainable strategy for the fixation of atmospheric N2 using full-spectrum solar energy.
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- 2022
4. Examining the Psychometric Properties of the Taiwanese Version of the Hospice Quality of Life Index
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Li-Ting H, Longcoy, Chun-Yi, Tai, Hung-Da, Dai, Susan C, McMillan, and Ardith Z, Doorenbos
- Abstract
Quality of life is an important outcome for people with cancer throughout their cancer trajectory. Having a valid and reliable instrument to measure the quality of life is critical. This cross-sectional study examined the psychometric properties of the Taiwanese version of the Hospice Quality of Life Index among patients with advanced cancer in Taiwan. There were 3 phases: (1) translation of the Hospice Quality of Life Index from English to Mandarin, (2) pilot testing among 30 targeted participants, and (3) field testing to examine validity and reliability. The results of confirmatory factor analysis indicated that the original factor structure of the Hospice Quality of Life Index did not fit the data. After 5 items were deleted from the original questionnaire, principal factor extraction with oblique rotation for exploratory factor analysis yielded 3 subscales: Social/Spiritual Well-Being, Psychological Well-Being, and Functional/Physiological Well-Being. For convergent validity, the small to moderate strength of associations showed shared variance with the Memorial Symptom Assessment Scale. The internal consistency was supported by Cronbach α ranging from 0.77 to 0.86. This study shows early evidence that the quality of life of people with advanced cancer can be appropriately assessed by the Taiwanese Hospice Quality of Life Index.
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- 2022
5. Daily Care Information System Requirements: Professional Service-Driven Service Blueprint Approach
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Yu-Chun Sang, Lih-Lian Hwang, Hung-da Dai, and Tung-Cheng Lin
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Service (business) ,Process management ,business.industry ,Service blueprint ,Health Informatics ,Service provider ,Long-Term Care ,Service process ,Computer Science Applications ,Health Information Management ,Blueprint ,Multidisciplinary approach ,Health care ,Information system ,Humans ,business ,Information Systems - Abstract
Background Long-term care (LTC) services are a professional service-driven (PSD) system; to deliver appropriate care services to residents, health care providers first need to collect appropriate patient data and make a professional assessment. A well-designed LTC information system should therefore consider the information requirements of multidisciplinary health care providers to adequately support their care services. Objectives This study proposed a modified service blueprint—the PSD service blueprint—for visualizing interdisciplinary service providers' input and output information requirements, which correspond to their service activities. Methods The PSD service blueprint comprises five layers and seven elements. We also present a case study to illustrate the blueprint's application to daily LTC services. Results Our proposed approach could clearly illustrate the daily care activities, service providers (main actors), actors' input and output information, and suggestions for LTC information system–related applications. Conclusion The proposed PSD service blueprint can not only gather interdisciplinary LTC service providers' information system requirements but also act as a mapping tool for visualizing the care service process.
- Published
- 2021
6. Application of intelligent algorithms in Down syndrome screening during second trimester pregnancy
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Hongguo Zhang, Ruizhi Liu, Si-Da Dai, Yuting Jiang, Xiaonan Hu, and Ling Li
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Down syndrome ,Down syndrome screening ,medicine.medical_specialty ,Support vector machine ,Classification and regression tree ,business.industry ,Obstetrics ,Prenatal screening ,General Medicine ,medicine.disease ,Intelligent algorithms ,03 medical and health sciences ,0302 clinical medicine ,Retrospective Study ,030220 oncology & carcinogenesis ,medicine ,Second trimester pregnancy ,030211 gastroenterology & hepatology ,business ,Algorithms ,Risk cutoff value - Abstract
BACKGROUND Down syndrome (DS) is one of the most common chromosomal aneuploidy diseases. Prenatal screening and diagnostic tests can aid the early diagnosis, appropriate management of these fetuses, and give parents an informed choice about whether or not to terminate a pregnancy. In recent years, investigations have been conducted to achieve a high detection rate (DR) and reduce the false positive rate (FPR). Hospitals have accumulated large numbers of screened cases. However, artificial intelligence methods are rarely used in the risk assessment of prenatal screening for DS. AIM To use a support vector machine algorithm, classification and regression tree algorithm, and AdaBoost algorithm in machine learning for modeling and analysis of prenatal DS screening. METHODS The dataset was from the Center for Prenatal Diagnosis at the First Hospital of Jilin University. We designed and developed intelligent algorithms based on the synthetic minority over-sampling technique (SMOTE)-Tomek and adaptive synthetic sampling over-sampling techniques to preprocess the dataset of prenatal screening information. The machine learning model was then established. Finally, the feasibility of artificial intelligence algorithms in DS screening evaluation is discussed. RESULTS The database contained 31 DS diagnosed cases, accounting for 0.03% of all patients. The dataset showed a large difference between the numbers of DS affected and non-affected cases. A combination of over-sampling and under-sampling techniques can greatly increase the performance of the algorithm at processing non-balanced datasets. As the number of iterations increases, the combination of the classification and regression tree algorithm and the SMOTE-Tomek over-sampling technique can obtain a high DR while keeping the FPR to a minimum. CONCLUSION The support vector machine algorithm and the classification and regression tree algorithm achieved good results on the DS screening dataset. When the T21 risk cutoff value was set to 270, machine learning methods had a higher DR and a lower FPR than statistical methods.
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- 2021
7. The precaution strategy toward the COVID-19 pandemic in the operating room of a tertiary hospital in Taiwan
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Hsu Ma, Chin Su Liu, Yi Han Lin, Wei Ming Chen, Hung Da Dai, Mei Yung Tsou, Jung Jyh Hung, and Fu Der Wang
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Operating Rooms ,Taiwan ,MEDLINE ,030204 cardiovascular system & hematology ,Disease cluster ,Tertiary Care Centers ,03 medical and health sciences ,0302 clinical medicine ,Acquired immunodeficiency syndrome (AIDS) ,Intervention (counseling) ,Pandemic ,medicine ,Humans ,Infection control ,Personal protective equipment ,Infection Control ,SARS-CoV-2 ,business.industry ,COVID-19 ,General Medicine ,medicine.disease ,Pneumonia ,030220 oncology & carcinogenesis ,Practice Guidelines as Topic ,Medical emergency ,business ,Algorithms - Abstract
Background The pandemic of SARS-CoV-2 (COVID-19), which began in December 2019, spread mostly from person to person through respiratory droplets. A recommendation was issued to postpone all elective surgical practices. However, some confirmed or suspected COVID-19 patients required life-saving emergent surgeries. Methods To facilitate emergent surgical interventions for these patients, we have reviewed the current literature and established an algorithm of precautions to be taken by operating room team members during the COVID-19 pandemic. Results The initial algorithm of preparation for surgical intervention during the COVID-19 pandemic was relatively simple. However, the abrupt increase of confirmed COVID-19 cases due to returned overseas travelers since mid-March 2020 disrupted the routine hospital clinical service. Due to the large number of febrile patients, the algorithm was therefore revised according to travel history, occupation, contact and cluster history (TOCC), unexplained fever/symptoms, and emergent/nonemergent surgery. TOCC (+) patients presenting with otherwise unexplained fever/symptoms would be regarded as belonging to the fifth category of "severe special infectious pneumonia." If the patient requires emergent surgery to relieve the non-life-threatening disorders, two times of negative COVID-19 tests are necessary before the operation is approved. For life-threatening situations without two negative results of COVID-19 tests, the operation schedule should be approved by the Chairman of Surgery Management Committee. Conclusion The application of a clear and integrated algorithm for operating room team members aids in effective personal protective equipment facilitation to keep both healthcare providers and patients safe as well as to prevent hospital-based transmission of COVID-19.
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- 2021
8. New RC-Imbalance Failure Mechanism of Well Charging Damage and The Implemented Rule
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Yu-Lin Chu, Hsi-Yu Kuo, Hung-Da Dai, Kuan-Hung Chen, Pei-Jung Lin, Chun-Ting Liao, Ta-Chun Lin, Ming Feng, Swercy Chiu, and Victor Liang
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- 2022
9. Formulations of dysphagia-friendly food matrices with calorie-dense starchy thickeners and their stability assessments
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Wei-Chi Huang, Hung-Da Dai, Tulakorn Sombatngamwilai, and Huai-Wen Yang
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Calorie ,Chemistry ,General Chemical Engineering ,010401 analytical chemistry ,Guar ,04 agricultural and veterinary sciences ,040401 food science ,01 natural sciences ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,Viscosity ,0404 agricultural biotechnology ,Food science ,Thickening ,Solubility ,Safety, Risk, Reliability and Quality ,Food Science - Abstract
Calorie-dense starchy thickeners (CDSTs) are preferable for dysphagic individuals while in terms of both sufficient moisture and energy intake. In the present study, we evaluated the thickening and anti-sedimentation effects of five commercial CDSTs and pre-screened the best candidate of germ rice (GR) powder for further formulation with xanthan and guar gums (XG and GG). The formulated model food matrices (MFMs) with different concentrations of CDST were prepared: nectar-like, honey-like, and pudding-like defined as 200 ± 50 mPa·s, 1050 ± 50 mPa·s, and 1800 ± 50 mPa·s, respectively. These CDST-MFMs were also subjected to evaluations of their physicochemical properties and stability. The solubility of MFMs containing GR could be as high as 60.95%; whereas the oil binding capabilities ranged between 3.77 and 4.22%, which were significantly higher (p
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- 2020
10. Indigenization of the median of markers for Down syndrome screening based on statistical analysis of medical big data
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Hongguo Zhang, Si-Da Dai, Ling Li, Li-Li Luo, Ruizhi Liu, and Zhu-Ming Hu
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Adult ,Big Data ,Medical big data ,Down syndrome ,medicine.medical_specialty ,lcsh:Gynecology and obstetrics ,03 medical and health sciences ,0302 clinical medicine ,Asian People ,Pregnancy ,Second-trimester screening ,medicine ,Humans ,Statistical analysis ,First-trimester screening ,lcsh:RG1-991 ,Retrospective Studies ,Indigenization ,Down syndrome screening ,030219 obstetrics & reproductive medicine ,Obstetrics ,business.industry ,Detection rate ,Obstetrics and Gynecology ,Regression analysis ,Retrospective cohort study ,medicine.disease ,Pregnancy Trimester, First ,Pregnancy Trimester, Second ,Female ,False positive rate ,business ,Biomarkers ,Maternal Serum Screening Tests - Abstract
Objective To indigenize the median of Down syndrome (DS) screening markers for first and second trimester, and compare the impact of the indigenized and built-in median data on the efficiency of DS screening. Materials and Methods Data derived from first and Second-trimester screening (FTS and STS) for DS, composed of selected pregnancies deemed to be normal, were examined in a retrospective study. Indigenization regression analysis was calculated by using five models to fit statistical the raw data. Multiple of median (MoM) values estimated by using indigenized medians were compared with those calculated by using built-in. Results This study established a regression equation which is more suitable for the median of each screening marker in the local pregnant women. The changes of median MoM of screening markers were statistically significant after indigenization. For FTS, the detection rate was 100% when the false positive rate was 5%, and the cut-off value was 1/262. On the other hand, for STS, the detection rate of the model with indigenized parameters was 77.42%, which is 16.13% higher than that of built-in parameters. Conclusion For the individual specific risk of pregnancy, when the indigenized parameters was used to calculate, is more accurately and screening effectiveness has been improved. This is a great reference significance for the current prenatal screening whether indigenized data should be used.
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- 2020
11. Nano-mineral induced nonlinear optical LiNbO3 with abundant oxygen vacancies for photocatalytic nitrogen fixation: boosting effect of polarization
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He Chengli, Shixiang Zuo, Chao Yao, Da Dai, Yan Xiangyu, Chaoying Ni, and Xiazhang Li
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Materials science ,Band gap ,Materials Science (miscellaneous) ,Doping ,Nanochemistry ,Second-harmonic generation ,02 engineering and technology ,Cell Biology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,law.invention ,law ,Photocatalysis ,Charge carrier ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,Crystallization ,0210 nano-technology ,Polarization (electrochemistry) ,Biotechnology - Abstract
Defective crystalline semiconductor plays a significant role in photocatalytic nitrogen fixation, however the rapid recombination of photoexcited electron/hole pairs largely reduces the efficiency. Spontaneous polarization of the nonlinear optical (NLO) material has emerged as a promising strategy for addressing the problem. Herein, a defects-rich NLO crystalline LiNbO3 modulated by natural nano-mineral palygorskite (LiNbO3/Pal) has been synthesized via sol–gel method. The intrinsic polarization of LiNbO3/Pal is investigated by second harmonic generation (SHG) measurements, which indicates an intensity of about 3.1 times that of typical NLO material KH2PO4 (KDP). The strong polarization can facilitate the separation of photogenerated charge carriers in the bulk phase and on the surface of LiNbO3/Pal. The existence of oxygen vacancies in LiNbO3/Pal may originate from doping of metal ions and active groups on the surface of Pal during crystallization of LiNbO3, which shortens the bandgap of LiNbO3 and facilitates the absorption and activation of N2 molecules. As a result, the polarization effect and rich oxygen vacancies make the LiNbO3/Pal an exceptional photocatalyst for N2 fixation. The 40 wt% LiNbO3/Pal composite achieves an average rate of photocatalytic NH4+ production of 52.57 μmol gcat−1 h−1 under simulated solar light, which is about sixfold higher than that of bulk LiNbO3. This work not only presents a new perspective on mineral modification of NLO material but also offers a cost-effective photocatalyst for nitrogen fixation.
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- 2020
12. Microwave hydrothermal synthesis of lanthanum oxyfluoride nanorods for photocatalytic nitrogen fixation: Effect of Pr doping
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Kun Ma, Wenjie Liu, Shixiang Zuo, Da Dai, Yan Xiangyu, Xiazhang Li, and Chao Yao
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Materials science ,chemistry ,Doping ,Photocatalysis ,Lanthanum ,Ultraviolet light ,Hydrothermal synthesis ,chemistry.chemical_element ,General Materials Science ,Nanorod ,Photochemistry ,Nitrogen ,Photon upconversion - Abstract
Photocatalytic fixation of nitrogen has been recognized as a green and promising strategy for ammonia synthesis under ambient conditions. However, the efficient reduction of nitrogen remains a challenge due to high activation energy of nitrogen and low utilization of solar energy. Herein, lanthanum oxyfluoride with different doping content of Pr3+ (LaOF:xPr3+) upconversion nanorods were synthesized by microwave hydrothermal method. Results indicated that the doping of Pr3+ generated considerable defects on the surface of LaOF which acted as the adsorption and activation center for nitrogen. Meanwhile, the Pr3+ ion narrowed the band gap and broadened the light response range of LaOF because LaOF:Pr3+ can upconvert visible light into ultraviolet light, which excite LaOF nanorods and improve the utilization of solar light. The doping amount of Pr3+ had critical effect on the photocatalytic nitrogen fixation performance which reached as high as 180 μmol·L−1·ho1 when the molar ratio of Pr3+ to LaOF was optimized to be 2%.
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- 2019
13. Deficiency of Tet3 in nucleus accumbens enhances fear generalization and anxiety-like behaviors in mice
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Bu‐Fang Fan, Bo Hao, Yun‐Da Dai, Li Xue, Yan‐Wei Shi, Lu Liu, Shou‐Min Xuan, Ning Yang, Xiao‐Guang Wang, and Hu Zhao
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Mice ,Neuronal Plasticity ,General Neuroscience ,Animals ,Neurology (clinical) ,Fear ,Anxiety ,Nucleus Accumbens ,Pathology and Forensic Medicine ,Dioxygenases ,Signal Transduction - Abstract
Stress-induced neuroepigenetic programming gains growing more and more interest in the studies of the etiology of posttraumatic stress disorder (PTSD). However, seldom attention is focused on DNA demethylation in fear memory generalization, which is the core characteristic of PTSD. Here, we show that ten-eleven translocation protein 3 (TET3), the most abundant DNA demethylation enzyme of the TET family in neurons, senses environmental stress and bridges neuroplasticity with behavioral adaptation during fear generalization. Foot shock strength dependently induces fear generalization and TET3 expression in nucleus accumbens (NAc) in mice. Inhibition of DNA demethylation by infusing demethyltransferase inhibitors or AAV-Tet3-shRNA virus in NAc enhances the fear generalization and anxiety-like behavior. Furthermore, TET3 knockdown impairs the dendritic spine density, PSD length, and thickness of neurons, decreases DNA hydroxymethylation (5hmC), reduces the expression of synaptic plasticity-related genes including Homer1, Cdkn1a, Cdh8, Vamp8, Reln, Bdnf, while surprisingly increases immune-related genes Stat1, B2m, H2-Q7, H2-M2, C3, Cd68 shown by RNA-seq. Notably, knockdown of TET3 in NAc activates microglia and CD39-P2Y12R signaling pathway, and inhibition of CD39 reverses the effects of TET3 knockdown on the fear memory generalization and anxiety. Overexpression of TET3 by Crispr-dSaCas9 virus delivery to activate endogenous Tet3 in NAc increases dendritic spine density of neurons in NAc and reverses fear memory generalization and anxiety-like behavior in mice. These results suggest that TET3 modulates fear generalization and anxiety via regulating synaptic plasticity and CD39 signaling pathway.
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- 2021
14. Photocatalytic nitrogen fixation over fluoride/attapulgite nanocomposite: Effect of upconversion and fluorine vacancy
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He Chengli, Da Dai, Yan Xiangyu, Chao Yao, Yuying Zhang, Xiazhang Li, and Shixiang Zuo
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Nanocomposite ,Materials science ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Metal ions in aqueous solution ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Photochemistry ,Nitrogen ,Photon upconversion ,Ammonia ,chemistry.chemical_compound ,Adsorption ,chemistry ,0202 electrical engineering, electronic engineering, information engineering ,Ultraviolet light ,Photocatalysis ,General Materials Science ,0210 nano-technology - Abstract
Developing cost-effective photocatalyst which converts nitrogen to ammonia under mild conditions remains a great challenge from both academic and industrial perspective. In this work, we synthesize one dimensional attapulgite (ATP) mineral supported Pr3+:CeF3 nanocomposite by a microwave hydrothermal method. Results indicate that adequate doping of Pr3+ facilitates the conversion of visible light into ultraviolet light which expands the adsorption range of solar energy. The abundant fluorine vacancies which generate from the incorporation of partial metal ions of ATP into the crystal lattice of CeF3 act as active sites promoting the adsorption of N2 as well as weakening the N ≡ N triple bond in the photocatalysis reaction. The 40 wt% loading of Pr3+:CeF3 exhibits the highest photocatalytic nitrogen fixation performance attributed to the formation of Z-scheme structure which not only improves the separation of photoexcited charge carriers, but also preserve the high redox potential to reduce nitrogen. This work provides a sustainable way for nitrogen fixation using solar energy based on natural mineral and beyond.
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- 2019
15. Advances in Experimental and Clinical Research of the Gouty Arthritis Treatment with Traditional Chinese Medicine
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Huan Liang, Wei Zhang, Xu-Yue Pan, Junde Wu, Wen-Da Dai, Pin Deng, Yu-Feng Ma, Yin-Ze Qi, Zhan-Hua Ma, Zhaojun Chen, Si-Yuan Lv, Fasen Huang, Jing-Lu Han, and Yan Wu
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medicine.medical_specialty ,business.industry ,Articular chondrocyte ,MEDLINE ,Review Article ,Traditional Chinese medicine ,medicine.disease ,Gout ,chemistry.chemical_compound ,Other systems of medicine ,Clinical research ,Complementary and alternative medicine ,chemistry ,medicine ,Uric acid ,Chinese pharmacopoeia ,Gouty arthritis ,Intensive care medicine ,business ,RZ201-999 - Abstract
Gouty arthritis (GA) is a multifactorial disease whose pathogenesis is utterly complex, and the current clinical treatment methods cannot wholly prevent GA development. Western medicine is the primary treatment strategy for gouty arthritis, but it owns an unfavorable prognosis. Therefore, the prevention and treatment of GA are essential. In China, traditional Chinese medicine (TCM) has been adopted for GA prevention and treatment for thousands of years. Gout patients are usually treated with TCM according to their different conditions, and long-term results can be achieved by improving their physical condition. And TCM has been proved to be an effective method to treat gout in modern China. Nevertheless, the pharmacological mechanism of TCM for gout is still unclear, which limits its spread. The theory of prevention and treatment of gout with TCM is more well acknowledged in China than in abroad. In this article, Chinese herbs and ancient formula for gout were summarized first. A total of more than 570 studies published from 2004 to June 2021 in PubMed, Medline, CNKI, VIP, Web of Science databases and Chinese Pharmacopoeia and traditional Chinese books were searched; the current status of TCM in the treatment of GA was summarized from the following aspects: articular chondrocyte apoptosis inhibition, antioxidative stress response, inflammatory cytokine levels regulation, uric acid excretion promotion, immune function regulation, uric acid reduction, and intestinal flora improvement in subjects with gout. The literature review concluded that TCM has a specific curative effect on the prevention and treatment of GA, particularly when combined with modern medical approaches. However, lacking a uniform definition of GA syndrome differentiation and the support of evidence-based medicine in clinical practice have provoked considerable concern in previous studies, which needs to be addressed in future research.
- Published
- 2021
16. [Research progress on long non-coding RNA (lncRNA) in osteoarthritis]
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Guo-da, Dai, Pei-Min, Wang, Jian-Ping, Cai, Song-He, Yan, and Han, Xia
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Chondrocytes ,Research ,Osteoarthritis ,Quality of Life ,Humans ,RNA, Long Noncoding - Abstract
Osteoarthritis(OA) is a common clinical disease. The incidence of OA increases significantly with age, and the quality of life of patients is seriously affected. In the pathogenesis of OA, cartilage degeneration is the main cause. There are many long non-coding RNA (lncRNA) specifically expressed in osteoarthritis, which is closely related to the occurrence and development of osteoarthritis. Based on the latest research from 2014 to 2019, this paper summarizes the differential expression of lncRNA in osteoarthritis, the mechanism of lncRNA regulating chondrocyte function, and the mechanism of lncRNA regulating cartilage matrix metabolism. The fact that the expression of lncRNA is altered at different stages of OA development indicates that lncRNA can be developed forlife. The biomarkers and therapeutic targets can provide reference for the prevention, treatment and research of osteoarthritis.
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- 2020
17. Full spectrum driven SCR removal of NO over hierarchical CeVO
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Xiazhang, Li, Zhendong, Wang, Haiyang, Shi, Da, Dai, Shixiang, Zuo, Chao, Yao, and Chaoying, Ni
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Removal of hazardous NO at low temperature via photo-assisted selective catalytic reduction (photo-SCR) strategy is promising, however fully harvesting of solar energy and achieving high SO
- Published
- 2019
18. The Measurement of Human Resource Based on Value Engineering
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Li-da Dai
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business.industry ,Computer science ,media_common.quotation_subject ,Value engineering ,Environmental economics ,Human resources ,business ,Function (engineering) ,Investment (macroeconomics) ,Corporation ,media_common - Abstract
Based on value engineering, the cost and function of human resource are analyzed in this paper. Then, the paper puts forward the measurement model of human resource integrating costs and corresponding function, i.e. comparing the cost with the discounted return of corporation and the weight of particular kinds of human resource in a specific year. In addition, several approaches to the enhancement of the efficiency of H&R investment are discussed.
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- 2019
19. Development of High Spectral Resolution Lidar System for Measuring Aerosol and Cloud
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Yingjian Wang, Ming Zhao, Dong Liu, Zhen Shang, Pang-Da Dai, Zhenzhu Wang, Zhiqing Zhong, Wang Bangxin, Min Tan, and Chenbo Xie
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Lidar ,law ,Environmental science ,Particle ,Molar absorptivity ,Spectral resolution ,Laser ,Atomic and Molecular Physics, and Optics ,Spectral line ,Remote sensing ,Aerosol ,law.invention ,Line (formation) - Abstract
A high spectral resolution lidar (HSRL) system based on injection-seeded Nd:YAG laser and iodine absorption filter has been developed for the quantitative measurement of aerosol and cloud. The laser frequency is stabilized at 80 MHz by a frequency locking system and the absorption line of iodine cell is selected at the 1111 line with 2 GHz width. The observations show that the HSRL can provide vertical profiles of particle extinction coefficient, backscattering coefficient and lidar ratio for cloud and aerosol up to 12 km altitude, simultaneously. For the measured cases, the lidar ratios are 10~20 sr for cloud, 28~37 sr for dust, and 58~70 sr for urban pollution aerosol. It reveals the potential of HSRL to distinguish the type of aerosol and cloud. Time series measurements are given and demonstrate that the HSRL has ability to continuously observe the aerosol and cloud for day and night.
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- 2015
20. Full spectrum driven SCR removal of NO over hierarchical CeVO4/attapulgite nanocomposite with high resistance to SO2 and H2O
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Haiyang Shi, Da Dai, Chaoying Ni, Xiazhang Li, Shixiang Zuo, Zhendong Wang, and Chao Yao
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Environmental Engineering ,Materials science ,Nanocomposite ,business.industry ,Health, Toxicology and Mutagenesis ,Selective catalytic reduction ,Solar energy ,Pollution ,Photon upconversion ,Catalysis ,Chemical engineering ,Photocatalysis ,Environmental Chemistry ,Nanorod ,Absorption (electromagnetic radiation) ,business ,Waste Management and Disposal - Abstract
Removal of hazardous NO at low temperature via photo-assisted selective catalytic reduction (photo-SCR) strategy is promising, however fully harvesting of solar energy and achieving high SO2/H2O tolerance still remain a challenge. Herein, the phosphoric acid modified natural attapulgite(P-ATP) was employed as a matrix to immobilize CeVO4 by microwave hydrothermal method. Results show that P-ATP provides abundant active sites facilitating the in situ grow of CeVO4 nanorods on its surface which hierarchically construct a dendritic-like photocatalyst. The near-infrared (NIR) light is upconverted to visible and UV light through CeVO4 which not only broaden the absorption range of solar light, but also build Z-scheme heterostructure with P-ATP enhancing the redox potential of charge carriers. The CeVO4/P-ATP nanocomposite can reach as high as 92 % for NO conversion under full-spectrum solar irradiation, while retaining nearly 60 % conversion under NIR light. Moreover, the catalyst exhibits outstanding tolerance with SO2 and H2O due to the presence of Ce species which can prevent NH3 from being sulfated, while ATP prevent catalyst from being corroded by H2O. This work may open up a new window for full-spectrum driven SCR of NO based on cost-effective mineral catalyst.
- Published
- 2020
21. Auto-Layering Wavelet Transfer to Remove the Circumstance Effect and Noise
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Pang Da Dai, Yi Zhou, Jing Liu, Jing Li Wang, Chang Hua Lu, Wei Zhang, Xue Xiao, and Yu-jun Zhang
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Digital image ,Noise ,Wavelet ,Approximation error ,Computer science ,business.industry ,General Engineering ,Computer vision ,Artificial intelligence ,Layering ,business ,Energy (signal processing) ,Image (mathematics) - Abstract
The accuracy of visibility measurement from night light sources image is usually affected by the circumstance light and noise. This paper presents an auto-layering wavelet transfer method to remove the circumstance effect and noise simultaneously. Firstly, the light propagation through the fog at night condition is formulized, where the model and features of night image with circumstance effect and noise is given. Secondly, we propose to use multi-scale features of wavelet transfer to decompose the image to remove the circumstance effect and noise, where an auto-layering method is used based on the energy ratio of wavelet coefficients. Experiments show that our method is able to remove the circumstance effect and noise simultaneously and to adjust the decomposed layering number automatically. Our method is not only suitable for many wavelet functions, but also preserves the light sources as well as their glows in the digital images. The relative error of using db4 is 3.16%, and the relative error of using sym2 is 2.02%.
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- 2013
22. Research on Algorithm of Vision-Based Night Visibility Estimation
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Jing Liu, Chang Hua Lu, Yi Zhou, Pang Da Dai, Yu-jun Zhang, and Jing Li Wang
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Vision based ,Computer science ,business.industry ,Visibility (geometry) ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Computer vision ,General Medicine ,Enhanced Data Rates for GSM Evolution ,Artificial intelligence ,business ,Luminance ,Algorithm ,Image (mathematics) - Abstract
Accurately achieve the luminance of light sources at night images is significantly important to vision-based night visibility estimation. In this paper, we propose a practical night visibility algorithm. This algorithm contains two main parts, light sources recognition and edge extraction. Firstly, we give the model of vision-based visibility estimation, and propose the framework of algorithm. Secondly, we give the method to extract light sources from multiple potential targets by the prior knowledge of space information. Then, we analysis the features of light source image, and explain the expanded temple to cut sub-image of light source, and induce in PS level set to segment the edge. Experiments show that, the light source average recognition precision is approach to 0.95 at the condition of moderate breeze, and compared with the manual segment, the precision of light source segment is approach to 0.99 at the condition of real visibility larger than 500m.
- Published
- 2013
23. Numerical Study on the Influence of Different Anvils on Explosive Welding
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Jian Rui Feng, Er Feng An, Kai Da Dai, Yuan Yuan, and Pengwan Chen
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Shock wave ,Materials science ,Mechanical Engineering ,Metallurgy ,chemistry.chemical_element ,Welding ,Condensed Matter Physics ,law.invention ,Explosion welding ,chemistry ,Mechanics of Materials ,Aluminium ,law ,General Materials Science ,Joint (geology) - Abstract
Explosive welding is an efficient method for metals welding. However, in explosive welding, the shock wave generated by the explosion can not only damage the sensitive structure in the area of the process, but also can actually destroy a welded joint immediately after its creation. By placing an additional structure (anvil) can reduce the influence of shock waves. The influence of different anvil on the explosive welding of aluminum and magnesium plates has been investigated by using AUTODYN Software in this paper. The results show that the steel anvil is much more appropriate than sand and magnesium.
- Published
- 2013
24. Analysis of the Measurement Conditions of Heavy Metal Enriched on the Filter Membrane Using X-Ray Fluorescence
- Author
-
Wei Zhang, Yu-jun Zhang, Nan Jing Zhao, Chun-long Wang, Yan Wei Gao, Dong Chen, Xiao Ya Yu, Jin Liu, Rong Zhang, and Pang Da Dai
- Subjects
Metal ,Excitation current ,Chemistry ,visual_art ,General Engineering ,Analytical chemistry ,visual_art.visual_art_medium ,X-ray fluorescence ,Membrane filter ,Fluorescence ,Pulse shaping ,Excitation - Abstract
In this paper, the measurement conditions of heavy metal enriched on the filter membrane using X-ray fluorescence were talked about. According to the heavy metal enriched on the film, the specific parameters were analysed. Through many experiments, the suitable parameters were decided. In order to excite mainly heavy metal in air, the excitation voltage should be not less than 30kV. The excitation current should be between 20μA and 60μA. The measured distance should be between 4mm and 15mm. The best choice of pulse shaping time is around 6.4μs. These parameters setting should have very good application value in air heavy metal measurement.
- Published
- 2013
25. Research of Measuring High Visibility at Night Based on Dual Light Sources Digital Image
- Author
-
Yu-jun Zhang, Pang Da Dai, and Chang Hua Lu
- Subjects
Computer science ,business.industry ,Visibility (geometry) ,General Engineering ,Context (language use) ,Luminance ,Stability (probability) ,Dual (category theory) ,Digital image ,Optics ,Range (statistics) ,Visibility ,business ,Remote sensing - Abstract
Research on measuring night visibility using digital images mainly focused on low visibility conditions nowadays. Also, the long term observation leads to fluctuations of the single light source, which would undermine the measuring range and precision. In this context, this paper presents the dual light sources measurement method to eliminate the fluctuations of single source and to achieve both high measuring range and precision at night conditions. The source of visibility measuring error is firstly formulated through an error analysis. Then we propose a dual light sources framework that yields two identical beams to measure the visibility, which is advantageous over the single light source method and capable of measuring high visibility. In the experiments, the stability of the dual light sources is firstly tested by a 72-hour running. The average luminance ration of dual light sources is 0.9932 and the average relative error is 0.04%. The relative error of dual light sources luminance ration is only 0.2% when the fluctuations of single source is as high as 2.28%. Then the dual light sources is applied in the digital image night visibility measuring system to evaluate its validity. The result shows that the dual light sources method is capable of measuring the range of 390 times of baseline (40m baseline) with the error less than 15%, which fully meets the meteorological demands.
- Published
- 2013
26. Taiwanese Version of the Work-Related Quality of Life Scale for Nurses: Translation and Validation
- Author
-
Fu In Tang, Hung-Da Dai, I-Ju Chen, and Shu Yu
- Subjects
Adult ,Male ,Psychometrics ,Concurrent validity ,Taiwan ,Work related ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Quality of life (healthcare) ,Cronbach's alpha ,Nursing ,Surveys and Questionnaires ,Medicine ,Humans ,Translations ,030212 general & internal medicine ,Workplace ,General Nursing ,Reliability (statistics) ,030504 nursing ,business.industry ,General Medicine ,Middle Aged ,Confirmatory factor analysis ,Scale (social sciences) ,Human resource management ,Quality of Life ,Female ,Nursing Staff ,0305 other medical science ,business - Abstract
Background: The shortage of professional nurses is a global issue of critical importance. Improving the retention and recruitment of nurses is necessary to reduce this shortage. The ability to measure the quality of work life (QWL) of nurses is important to understand the current QWL status among nurses and to develop appropriate improvement strategies. The two instruments that are currently used in Taiwan both require excessive amounts of time to complete. Furthermore, the results that these two instruments generate are not easily interdisciplinary and international comparisons. Purpose: The aims of this study were to translate into Chinese the English version of the Work-Related Quality of Life Scale (WRQoL) that was developed by Van Laar, Edwards, and Easton (2007) and then to determine the reliability and validity of this Chinese-version scale in terms of measuring the QWL of nurses in Taiwan. Methods: The WRQoL was translated from English into Chinese using forward-translation with group discussions, back-translation, and verification of conceptual equivalence. Concurrent validity, test-retest reliability, and internal consistency reliability were determined in two samples of nurses (n = 30 and n = 213 for Phases 1 and 2, respectively) from a medical center in Taiwan during September 2009. Results: The 23-item Taiwanese version of the WRQoL showed satisfactory concurrent validity with a Taiwanese QWL scale (correlation = .75). The 3-week test-retest reliability was .89, and the Cronbach's alpha was .88, indicating high internal consistency reliability. Conclusions/Implications for Practice: The Taiwanese version of the WRQoL is acceptable for measuring the QWL of nurses in Taiwan. Larger scale studies are recommended for confirmatory factor analysis. This tool may be used for human resources management and policy-making applications, providing the potential to help retain and recruit nurses in Taiwan. Furthermore, the Taiwanese-version scale may be used to compare work-related quality of life between Taiwanese nurses and their counterparts overseas.
- Published
- 2016
27. Numerical Simulation of the Shock Compaction of W/Cu Powders
- Author
-
Kai Da Dai and Pengwan Chen
- Subjects
Materials science ,Computer simulation ,business.industry ,Mechanical Engineering ,Structural engineering ,Shock compaction ,Deformation (meteorology) ,Condensed Matter Physics ,Micromechanical model ,Mechanics of Materials ,Lagrange formulation ,General Materials Science ,Particle size ,Composite material ,business ,Longitudinal wave ,Plane stress - Abstract
A numerical simulation approach is used to study the deformation and temperature distribution of W/Cu powders under shock compaction. A two-dimensional micromechanical model is employed where only a few particles are considered. The simulation is performed using plane strain element and Lagrange formulation. Shock compaction is achieved by bringing in the W/Cu powders an intense compression wave using a high-velocity rigid wall. The effects of compact velocity, particle size and friction on the particle deformation and temperature distribution are discussed based on the results of simulations. The study provides a detailed understanding of the micromechanical behavior of metal powders during shock compaction process.
- Published
- 2011
28. An Algorithm for the Hypervelocity Launcher Simulation of High-Low Density Flyer Plates
- Author
-
Jian-bo Hu, Jing-song Hua, Jing-song Bai, Ping Li, and Chen-da Dai
- Subjects
Physics ,Shock wave ,Finite volume method ,General Computer Science ,Computer simulation ,Numerical analysis ,symbols.namesake ,Modeling and Simulation ,Euler's formula ,symbols ,Volume of fluid method ,Hypervelocity ,Piecewise ,Algorithm - Abstract
In this paper, we present a numerical method to simulate the hypervelocity launcher (HVL) experiment in which the two-stage light-gas gun impact launches flyers to hypervelocity. HVL is a complex process in numerical simulation, which includes multi-materials, multi-interfaces, huge distortion, high densities and severe shock wave problems, etc. A two-step Euler high-resolution finite volume scheme is used to solve the multi-fluid hydrodynamic equations. The first step is the Lagrange step in which the computation cells are distorted to follow the material motion, and the second step is the Remap step where the distorted cells are mapped back to the Euler meshes. Based on the Volume of Fluids model (VOF) and parabolic piecewise method (PPM), a shock wave physics code named multi-fluid parabolic piecewise method (MFPPM) is developed to simulate the experimental configuration of the hypervelocity launchers and the resolution of the algorithm is also tested. We emphasize the distinguished features of the code that aid in understanding the sensitivity of hypervelocity launcher calculations to the numerical methodology. The MFPPM code is verified and validated by simulating a series of hypervelocity launcher experiments implemented in Sandia National Laboratories. Good agreements are shown when comparing the numerical results with experimental data. Besides, in our National Key Laboratory for Shock Wave and Detonation Physics Research, two new models of the high/low density (Tantalu m/ Titanium) flyer plates HVL experiment are simulated by the code. Again, the numerical results and experimental data agree well with each other.
- Published
- 2009
29. Nonintubated transareolar single-port thoracic sympathicotomy with a needle scope in a series of 85 male patients
- Author
-
Jian-Feng Chen, Fan-Cai Lai, Xu Li, Jianbo Lin, Quan Du, Yuan-Da Dai, Min Lin, and Yuan-Rong Tu
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Operative Time ,030204 cardiovascular system & hematology ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Port (medical) ,Sore throat ,Thoracoscopy ,Medicine ,Intubation ,Humans ,Hyperhidrosis ,Sympathectomy ,medicine.diagnostic_test ,business.industry ,Middle Aged ,Thoracoscopes ,Surgery ,Intravenous anesthesia ,Patient Satisfaction ,030220 oncology & carcinogenesis ,Anesthesia ,Feasibility Studies ,medicine.symptom ,business ,Abdominal surgery - Abstract
Traditional endoscopic thoracic sympathicotomy is usually performed through an axillary incision with 5-mm thoracoscope under general anesthesia with endotrachea intubation. Nonintubated transareolar single-port thoracic sympathicotomy with a needle scope has rarely been attempted. The objective of this study is to evaluate the feasibility and safety of this minimally invasive technique in managing primary palmar hyperhidrosis (PPH). From May 2012 to May 2014, a total of 85 male patients with severe PPH underwent transareolar single-port thoracic sympathicotomy by use of a 2-mm needle scope under total intravenous anesthesia without endotrachea intubation. All procedures were successfully performed with a mean operating time of 13.5 min. The palms of all patients became dry and warm as soon as the sympathetic chain was cut off. There were no sore throat, and all the patients regained consciousness rapidly after surgery. Eighty-two patients (96.5 %) were discharged from the hospital on the first postoperative day. The postoperative complications were minor, and no patients developed Horner’s syndrome. At 6 months postoperatively, there is no obvious surgical scar on the chest wall, and none of the patients complained about postoperative pain. Compensatory sweating appeared in 31 patients. No recurrent symptoms were observed in our study. One-year follow-up revealed an excellent cosmetic result and degree of satisfaction. Nonintubated transareolar single-port needlescopic thoracic sympathicotomy is a safe, effective and minimally invasive therapeutic procedure, which can be performed in routine clinical practice for male PPH patients.
- Published
- 2015
30. [Research on night visibility inversion algorithm based on the dual light sources image and curve evolution theory]
- Author
-
Pang-Da, Dai, Yu-Jun, Zhang, Chang-Hua, Lu, Yi, Zhou, Jing-Li, Wang, and Xue, Xiao
- Abstract
In the present paper, we propose a novel night visibility inversion algorithm. The key idea is based on the curve evolution theory in the context of dual light sources. First, we describe the features of the dual light sources night visibility inversion method, and explain the relationship between fluctuation of light source intensity and curve evolution with the special characters. Then, level set method is introduced ito define the light source intensity and establish the model with visibility inversion, and the algorithm formula is detailed. Experiments results show that, the algorithm is characterized with a strong robustness and compared with the standard visibility, the correlation of visibility result reaches up to 0.98 in the range of 2,000 meter to 12,000 me- ter, which can be used in the visibility monitoring with a large range, high precision and strong robustness.
- Published
- 2014
31. [Research on night visibility estimation method based on image features of dual light sources]
- Author
-
Pang-Da, Dai, Yu-Jun, Zhang, Chang-Hua, Lu, Yi, Zhou, Jing, Liu, Xue, Xiao, Wen-Qing, Liu, and Jing-Li, Wang
- Abstract
Haze, rain and snow bring a lot of inconvenience in our daily life, especially produce serious potential safety hazard for night transport. In the present paper the authors propose the vision-based dual light sources visibility method to estimate night visibility. This method is significantly advantaged with wide range, high precision and low cost, and has a good robustness in many kinds of weather conditions. Firstly, the authors give the basic visibility estimation model under the atmosphere multiple scattering theory. Secondly, the authors propose the dual light sources method to remove the luminance fluctuations of light sources and the atmosphere light effect, and formulize the algorithm to accurately gain information of light sources from the dual light sources image. At last, the authors design the dual light sources system and conduct a long time experiments under various atmosphere conditions. The experiments show that, with the baseline of 35 m, the visibility range is up to 15 000 m, and relative error is below 20%. This method and system can satisfy the demand of meteorological department and transport agency.
- Published
- 2014
32. The Mutation without childrenrgl Causes Ecdysteroid Deficiency in Third-Instar Larvae of Drosophila melanogaster
- Author
-
Negusse Habtemichael, Jasmine Wismar, Lawrence I. Gilbert, Elisabeth Gateff, Ji-da Dai, and James T. Warren
- Subjects
DNA, Complementary ,animal structures ,Molecular Sequence Data ,Mutant ,without children ,mental retardation ,03 medical and health sciences ,chemistry.chemical_compound ,Exon ,0302 clinical medicine ,Animals ,Drosophila Proteins ,Humans ,Amino Acid Sequence ,ecdysone ,Molecular Biology ,Alleles ,030304 developmental biology ,0303 health sciences ,Ecdysteroid ,Polytene chromosome ,Base Sequence ,zinc finger ,biology ,Homozygote ,fungi ,Ecdysteroids ,Cell Biology ,biology.organism_classification ,Molecular biology ,3. Good health ,DNA-Binding Proteins ,Microscopy, Electron ,Drosophila melanogaster ,Phenotype ,chemistry ,Mutagenesis ,Larva ,ring gland ,Chromosomal region ,Insect Proteins ,Steroids ,030217 neurology & neurosurgery ,Drosophila Protein ,Ecdysone ,Transcription Factors ,Developmental Biology - Abstract
Larvae homozygous for the recessive lethal allele without children(rgl) (woc(rgl)) fail to pupariate. Application of exogenous 20-hydroxyecdysone elicits puparium formation and pupation. Ecdysteroid titer measurements on mutant larvae show an endocrine deficiency in the brain-ring gland complex, which normally synthesizes ecdysone, resulting in a failure of the larvae to achieve a threshold whole body hormone titer necessary for molting. Ultrastructural investigation revealed extensive degeneration of the prothoracic cells of the ring gland in older larvae. The woc gene, located in polytene chromosomal region 97F, consists of 11 exons. A 6.8-kb transcript is expressed throughout development but is absent in the mutant woc(rgl) larvae. The woc gene encodes a protein of 187 kDa. Eight zinc fingers of the C2-C2 type point to a possible function as a transcription factor. The woc protein shows considerable homology to human proteins which have been implicated in both mental retardation and a leukemia/lymphoma syndrome.
- Published
- 2000
33. Programmed cell death of the prothoracic glands of Manduca sexta during pupal-adult metamorphosis
- Author
-
Ji-da Dai and Lawrence I. Gilbert
- Subjects
Programmed cell death ,biology ,Endoplasmic reticulum ,media_common.quotation_subject ,Metamorphosis, Biological ,Pupa ,Ecdysteroids ,Apoptosis ,Vacuole ,biology.organism_classification ,Prothoracic gland ,Biochemistry ,Cell biology ,Manduca sexta ,Cytoplasm ,Endocrine Glands ,Manduca ,Insect Science ,Animals ,Steroids ,Metamorphosis ,Molecular Biology ,media_common - Abstract
The degeneration of the prothoracic glands of Manduca sexta during pupal-adult metamorphosis was analyzed by both light and transmission electron microscopy, and correlated with a functional analysis of the ability of the prothoracic glands to synthesize ecdysteroids in vitro. Apoptosis of degenerating glandular cells was also examined by in situ indirect immunofluorescein detection of digoxigenin-labeled genomic DNA cleavage (the TUNEL method). The ability of the prothoracic gland to synthesize ecdysteroids reached a peak 4 days after pupation, decreased drastically on day 6 and then decreased further to the basal level 2 days later. Prothoracic gland degeneration was initiated on day 6 and was characterized by nuclear condensation, cytoplasmic budding, giant autophagic vacuoles, the disappearance of the smooth endoplasmic reticulum and intercellular channels, and the fragmentation of the cytoplasm into membrane-bound bodies. The cell debris of these degenerating cells was then engulfed by numerous phagocytic hemocytes. The results of the analysis of apoptosis by immunofluorescence detection are in complete accord with the histological, ultrastructural and radioimmunoassay data, suggesting that apoptosis is the basic mechanism for programmed cell death of the cells comprising these vital glands.
- Published
- 1997
34. Immunoreactivity of neurosecretory granules in the brain-retrocerebral complex ofManduca sextato heterologous antibodies againstBombyxprothoracicotropic hormone and bombyxin
- Author
-
Ji-da Dai, Lawrence I. Gilbert, and Akira Mizoguchi
- Subjects
medicine.medical_specialty ,biology ,medicine.drug_class ,Immunogold labelling ,Monoclonal antibody ,biology.organism_classification ,Molecular biology ,Endocrinology ,Cytoplasm ,Manduca sexta ,Internal medicine ,medicine ,Immunohistochemistry ,Animal Science and Zoology ,Prothoracicotropic hormone ,Corpus allatum ,Developmental Biology ,Bombyx - Abstract
Summary A monoclonal antibody against a synthetic pentadecapeptide corresponding to the N-terminal end of Bombyx-prothoracicotropic hormone (PTTH: 1–15) and a monoclonal antibody against a synthetic decapeptide corresponding to the N-terminal portion of the A-chain of bombyxin-1, bombyxin (1–10), were used as parallel probes to localize both molecules at the cellular and subcellular levels in the brain-retrocerebral complex of Manduca sexta. Immunohistochemical analysis revealed that molecules immunochemically similar to Bombyx-PTTH were localized in the cytoplasm of two pairs of dorso-lateral neurosecretory cells (L-NSC III) and could be traced along their axons to the corpora cardiaca (CC) and corpora allata (CA), whereas bombyxin-like material was absent from these cells and was detected only in the cytoplasm of four pairs of median neurosecretory cells (M-NSCs). Immunocytochemical labelling at the ultrastructural level using the PTTH antibody showed high specificity with the 5 nm immunogold particles ...
- Published
- 1994
35. [Herbert screw fixation for the treatment of capitulum radius fracture: a report of 15 cases]
- Author
-
Jian-ping, Ca and Guo-da, Dai
- Subjects
Adult ,Male ,Fracture Fixation, Internal ,Adolescent ,Bone Screws ,Humans ,Female ,Middle Aged ,Radius Fractures - Abstract
To observe the short-term therapeutic effects of Herbert screw fixation on type Mason II, Ill radial head fractures.From March 2008 to July 2010,15 patients with Mason II, III radial head fractures were treated by open reduction and Herbert screw fixation including 6 males and 9 females with the mean age of 32 years (from 18 to 55). Seven cases were left and 8 cases were right. The interval from injury to hospitalization ranged from 3 to 10 hours. The clinical symptoms were swelling, pain, restricted movement in elbow. Bonycrepitus were heard on the elbow joint and X-ray film showed radial head fractures. Mayo elbow scoring system was used to evaluate recovery of elbow function.All the incisions primarily healed without myositis ossificans. All the patients were followed up for 6 to 15 months. According to Mayo elbow score, the result was excellent in 8 cases, good in 5 cases and fair in 2 cases. Mayo score was (86.67+/-1.26) points, which including pain (53.33+/-9.76), joint function(27.33+/-4.58), joint stability(6.00+/-2.07) elbow joint mobility was 70 degrees-130 degrees with the average of (105+/-10) degrees, forearm rotation was 1000-1300 with the average of (120+/-16) degrees.Treatment of Mason II, II radial head fractures with Herbert screw fixation has advantages of satisfactory reduction, reliable fixation,easy operating and early movement of joint.
- Published
- 2011
36. Enterprises competitiveness in regression analysis based on customer loyalty model
- Author
-
Ying-da Dai
- Subjects
Customer delight ,Customer retention ,Customer advocacy ,Customer equity ,Customer lifetime value ,Business ,Marketing ,Customer to customer ,Customer intelligence ,Loyalty business model - Abstract
With the increasingly fierce market competition, enterprise pay more and more attention on customer relationship management. Customer loyalty, can effectively enhance the competitiveness of enterprises. This paper describes the research model of customer loyalty, and with the findings of the insurance companies, the formation of customer loyalty, impact factor and enhance programs is discussed in detail. Adopt empirical methods, such as the questionnaire survey to collect data, factor analysis to identify variables, a regression model. Explore notable influence on customer loyalty respectively for the different drive variables. The paper not only innovated the theory of customer loyalty, but also to have innovated instruction value for business practices.
- Published
- 2011
37. On realizing optical CDMA signatures reconfiguration with composite coded waveguide grating
- Author
-
Jen-Fa Huang, Yao-Tang Chang, and You-Da Dai
- Subjects
Computer science ,Code division multiple access ,business.industry ,Control reconfiguration ,Data_CODINGANDINFORMATIONTHEORY ,Grating ,Signature (logic) ,Single antenna interference cancellation ,Linear network coding ,Computer Science::Multimedia ,Electronic engineering ,Codec ,Transceiver ,business ,Computer Science::Information Theory ,Computer network - Abstract
In views of optical CDMA confidentiality, this paper proposes a signature reconfiguration scheme over the OCDMA network coder/decoders (codecs) design. By exclusively assigning to each network user a set of pseudo-orthogonal M-sequence signature codes and selecting one among them to represent each user's signature. A central node station is assumed to monitor network traffic condition and to signal transceiver coder-decoder pair to perform signature codes changing. We structure the detailed M-signature codecs design over arrayed-waveguide grating devices. We also use the successive interference cancellation (SIC) technique to enhance the system performance.
- Published
- 2011
38. On signatures reconfiguration of waveguide-grating-based optical CDMA network coder/decoders
- Author
-
Jen-Fa Huang, Ta-Chun Nieh, and You-Da Dai
- Subjects
Signal processing ,Computer science ,Code division multiple access ,Optical communication ,Control reconfiguration ,Data_CODINGANDINFORMATIONTHEORY ,Arrayed waveguide grating ,law.invention ,law ,Linear network coding ,Computer Science::Multimedia ,Electronic engineering ,Codec ,Decoding methods ,Computer Science::Information Theory - Abstract
In views of reconfiguring optical CDMA (OCDMA) network coder/decoders (codecs), a dynamic signature coding scheme structured over arrayed-waveguide gratings (AWGs) is devised. The signature reconfiguration can find applications on enhancing OCDMA network confidentiality. On the basis of cyclic and periodic characteristics of M-sequence codes compatible with free-spectral range (FSR) of novel prime-dimension AWGs, numerical design examples are illustrated throughout the network codecs' configuration and operation.
- Published
- 2011
39. Granulocyte-macrophage colony-stimulating factor and interleukin 4 induce the malignant transformation of the bone marrow-derived human adult mesenchymal stem cells
- Author
-
Xiao-Gang, Zhou, Yi, Yang, Jin-Song, Yang, Jian, Zhou, Tao-Lin, Fang, Wen-da, Dai, and Zheng-Rong, Chen
- Subjects
Cell Transformation, Neoplastic ,Granulocyte-Macrophage Colony-Stimulating Factor ,Humans ,Bone Marrow Cells ,Mesenchymal Stem Cells ,Interleukin-4 ,Flow Cytometry ,Immunohistochemistry ,Cells, Cultured - Abstract
The purpose of the study was to examine the effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) on the bone-marrow-derived human adult mesenchymal stem cells (hMSCs).The hMSCs were isolated and cultured with GM-CSF and IL-4 for a period of one month. A single colony of transformed cells was then isolated and their phenotype was characterized by morphology, surface marker expression, and in vivo tumorigenesis.After one month culture, the transformed mesenchymal cells exhibited the morphology and phenotype similar to those of tumor cells, and also caused multiple fast growing lung deposits when it was injected into immunodeficient mice.Cytokines-driven malignant transformation of hMSCs may be a useful model for studying signaling pathways initiating malignant transformation of hMSC.
- Published
- 2011
40. Prime-length M-signatures reconfiguration to enhance optical CDMA confidentiality
- Author
-
Yao-Tang Chang, Chun-Ming Huang, You-Da Dai, and Jen-Fa Huang
- Subjects
Computer science ,business.industry ,Code division multiple access ,Control reconfiguration ,Signature (logic) ,Digital signature ,Code (cryptography) ,Codec ,Confidentiality ,Transceiver ,business ,Computer Science::Cryptography and Security ,Computer Science::Information Theory ,Computer network - Abstract
Dynamic signature reconfiguration is proposed to combat with eavesdroppers to enhance confidentiality over multi-rate optical code-division multiple-access (OCDMA) networks. The code reconfiguration is achieved by exclusively assigning to each network user a set of orthogonal or pseudo-orthogonal codes and randomly selecting one among them to represent each user's signature. A central node station is assumed to monitor network traffic condition and to signal transceiver coder-decoder pair to perform signature codes changing. We illustrate the confidentiality enhancement by dynamically reconfiguring user signatures using prime-lengths M-sequence codes. When the set of signature codes increases and the eavesdropper's codes detection becomes more difficult, thus network confidentiality is significantly increased.
- Published
- 2010
41. Innovation of Business Cost System under 'Speed Economy'
- Author
-
Li-Da Dai
- Subjects
Economy ,Cost estimate ,Total cost ,Total absorption costing ,Cost engineering ,Relevant cost ,Cost centre ,Business ,Semi-variable cost ,Implicit cost - Abstract
Whether a business can make swift reaction to various markets needs become a crucial factor to gain excessive profit in intensive competition of speed economy. This article analyses the influences of speed economy cost system such as: normal and standardized cost system are not suitable for the calculation of individualized products. Cost information offered by traditional cost calculation method can not reflects the cost structure of individualized product under speed economy. The traditional cost control system concentrated on "cost maintain" is hardly to meet the need of cost control on the whole life cycle of products. Consequently, the paper puts forward the following suggestions: form dynamic cost calculation model based on the analysis of "activity chain & value chain". Establish collection system of cost information to restore the real fact of cost; set up bi-track cost control system facing small-sized manufacturing units.
- Published
- 2009
42. [Progresses in bone tissue engineering]
- Author
-
Juan, Li, Wen-da, Dai, and Jian, Dong
- Subjects
Osteoblasts ,Tissue Engineering ,Tissue Scaffolds ,Osteogenesis ,Animals ,Humans ,Cell Differentiation ,Bone and Bones - Abstract
Bone tissure engineering plays an important role in tissure engineering. It typically uses an osteoblasts, artificial extracellular matrix (scaffold), and osteoinductive factors which promote cell attachment, differentiation, and mineralized bone formation. So it contents three problems at least: osteoblasts culture in vivo and in vitro, scaffold studies and regulation factors. Bone defect caused by trauma, tumor and inflammation is a frequent and formidable problem in clinical orthopedics. It appears that artificial bone produced by bone tissure engineering can save the problem well. With the development of tissue engineering, bone tissue engineering is developing rapidly. However, seldom experiments are on human body, and fewer productions of bone tissure engineering are used in clinic.
- Published
- 2009
43. An autoradiographic and immunocytochemical analysis of ecdysteroids and ecdysteroid binding sites in target cells ofDrosophila melanogaster
- Author
-
Madhabananda Sar, Lawrence I. Gilbert, Ji-da Dai, and James T. Warren
- Subjects
Exocrine gland ,medicine.medical_specialty ,Ecdysteroid ,animal structures ,biology ,Salivary gland ,fungi ,Prothoracic gland ,biology.organism_classification ,Cell biology ,chemistry.chemical_compound ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Internal medicine ,Juvenile hormone ,medicine ,Animal Science and Zoology ,Drosophila melanogaster ,Corpus allatum ,Ecdysone ,Developmental Biology - Abstract
Summary Ecdysteroid localization in target tissues of Drosophila melanogaster was demonstrated by the utilization of low temperature autoradiography and immunohistochemistry. Autoradiographic studies utilized high specific activity [3H]ponasterone A, an ecdysteroid with exceptional molting hormone activity in Drosophila. The data revealed a selective nuclear concentration of the labelled ligand in cells of the salivary gland, corpus allatum (source of juvenile hormone), prothoracic gland (source of ecdysone) and the central nervous system. Nuclear localization was also observed in epithelial cells of the esophagus and muscle cells of the pharynx and mandibles, etc. The specific labelling of cell nuclei was prevented by incubation of the tissue with [3H]ponasterone A in the presence of excess unlabelled ponasterone A. Nuclear localization of ponasterone A in the salivary gland was also observed when using an antiserum against ecdysteroids and an avidin-biotin-complex (ABC) detection system. The staining sh...
- Published
- 1991
44. Metamorphosis of the corpus allatum and degeneration of the prothoracic glands during the larval-pupal-adult transformation of Drosophila melanogaster: A cytophysiological analysis of the ring gland
- Author
-
Ji-da Dai and Lawrence I. Gilbert
- Subjects
medicine.medical_specialty ,Invertebrate Hormones ,media_common.quotation_subject ,Biology ,Halloween genes ,Corpora Allata ,Internal medicine ,medicine ,Animals ,Metamorphosis ,Molecular Biology ,media_common ,fungi ,Metamorphosis, Biological ,Pupa ,Ecdysteroids ,Cell Biology ,Prothoracic gland ,biology.organism_classification ,Neurosecretory Systems ,Microscopy, Electron ,Drosophila melanogaster ,Endocrinology ,Insect Hormones ,Larva ,Juvenile hormone ,Microscopy, Electron, Scanning ,Ultrastructure ,Corpus allatum ,Developmental Biology ,Endocrine gland - Abstract
The degeneration of the prothoracic glands of Drosophila melanogaster during pupal-adult metamorphosis was analyzed by light microscopy, scanning, and transmission electron microscopy. The ultrastructural observations were correlated with the ability of the ring gland to synthesize ecdysteroids in vitro. The ring gland is prominent during larval life and is identifiable until just before adult eclosion but undergoes dramatic changes in location, shape, size, ultrastructure, and function during pupal-adult development. Prothoracic gland degeneration is characterized by: a gradual decrease in its ability to synthesize ecdysteroids; a decreasing quantity of smooth endoplasmic reticulum (SER) and mitochondria; the absence of intercellular channels; cytoplasmic fragmentation; and the separation of the prothoracic gland from the corpus allatum and corpus cardiacum. An ultrastructural analysis of the corpus allatum during larval-pupal-adult metamorphosis and adult life was also correlated with function, i.e., juvenile hormone biosynthesis, using a radiochemical assay of ring glands and adult corpora allata in vitro. A relatively high concentration of SER, mitochondria, and mitochondrion-scalariform junction complexes are typical features of an active corpus allatum cell. The migration of the corpus allatum from the ring gland to its position as a separate gland in the adult fly was studied in detail. The capacity of the corpus allatum to synthesize juvenile hormone is at its peak in the ring gland of the early wandering third instar larva, whereas the corpus allatum of 2-day-old female adults displayed the greatest synthetic activity during adult life. The physiological significance of the alterations in gland activity is discussed.
- Published
- 1991
45. [Osteoblastic differentiation and in vivo osteogenic activity of marrow-derived mesenchymal stem cells stimulated by Tacrolimus: experiment with rats]
- Author
-
Jian, Dong, Wen-da, Dai, Tao-lin, Fang, Hong, Lin, and Toshimasa, Uemura
- Subjects
Male ,Osteoblasts ,Osteocalcin ,Bone Marrow Cells ,Cell Differentiation ,Mesenchymal Stem Cells ,Alkaline Phosphatase ,Blotting, Northern ,Rats, Inbred F344 ,Tacrolimus ,Rats ,Osteogenesis ,Microscopy, Electron, Scanning ,Animals ,RNA, Messenger ,Immunosuppressive Agents - Abstract
To investigate the effect of the immunosuppressant Tacrolimus (FK506) on the osteoblastic differentiation and in vivo osteogenic inducement of bone marrow-derived mesenchymal stem cells (MSCs).MSCs were derived from Fischer 344 rats. Some MSCs were cultured with L-ascorbic acid-2-phosphate (AsAP) and beta-glycerophosphate (beta-GP) or FK506 plus AsAP and beta-GP. The alkaline phosphatase (APase) activity and calcium deposition were detected 4, 8, 12, and 16 days after the culture. Scanning electron microscopy was used to examine the calcified nodules. Northern blotting was used to detect the mRNA expression of osteocalcium. Multiparous beta-tricalcium phosphate (beta-TCP) ceramic cubes were dipped into 2 kinds of suspension of MSCs, treated by FK506 + AsAP + beta-GP or AsAP + beta-GP, so as to produce 48 pieces of MSCs/beta-TCP complex that were randomly divided into 2 equal groups to be cultured with AsAP + beta-GP or AsAP + beta-GP + FK506 for 4 weeks. The these pieces were transplanted into the subcutaneous sites of the rats' backs and were taken out 4 and 8 weeks later respectively for histological examination.In vitro assays showed that the APase activity, calcium deposition, expression of osteocalcin mRNA of the FK506 + AsAP + beta-GP group at any time points were all significantly higher than those of the AsAP + beta-GP group (all P0.05). SEM showed that since the 16th day after culture calcified nodules began to be seen in the FK506 + AsAP + beta-GP group. Since the 4th weeks after transplantation remarkable new bone formation could be seen in the FK506 treated MSCs/beta-TCP complexes in comparison with those MSCs/beta-TCP complexes without treatment with FK506.Greatly enhancing the in vitro osteoblastic differentiation and in vivo osteogenesis of MSCs, FK506 has a potential value as a bone growth factor and may improve the clinical result of bone transplantation used to treat large bone defect. The results of this experiment also contributes to a better understanding on the mechanism of immunosuppressants.
- Published
- 2007
46. A study of role stress, organizational commitment and intention to quit among male nurses in southern Taiwan
- Author
-
Hung-Da Dai, Hsing-Yi Yu, Jiunn-Horng Lou, and Hsiu-Yueh Hsu
- Subjects
Adult ,Male ,Role stress ,media_common.quotation_subject ,Southern taiwan ,Taiwan ,Personnel Turnover ,Organizational commitment ,Intention to quit ,Job Satisfaction ,Promotion (rank) ,Nursing ,Surveys and Questionnaires ,Medicine ,Humans ,General Nursing ,media_common ,Response rate (survey) ,Stereotyping ,business.industry ,Professional development ,Significant part ,General Medicine ,Nurses, Male ,Cross-Sectional Studies ,Regression Analysis ,business ,Stress, Psychological - Abstract
Gender and sex role stereotyping are recognized as having the potential to limit the professional development of males within the nursing profession. The purpose of this study was to understand the relationships between demographic data and the dimensions of role stress, organizational commitment, and intentions to quit among male nurses in southern Taiwan. Research also investigated the correlations with three dependent variables and identified best predictors of male nurse intentions to quit the nursing profession. A total of 91 male nurses volunteered to participate in this cross-sectional research. Research results were based on data collected from questionnaires sent by mail to participants. A total of 76 valid questionnaires were returned and used in analysis (response rate = 83.5%). Findings pointed to patients, colleagues and society as the major sources of role stress for male nurses. These sources of stress, and the resultant intention to quit on the part of male nurses, are due in significant part to the widespread stereotyping of the profession of nursing as a "woman's occupation". Such stress pressures male nurses to consider quitting to take jobs in other professional fields. Role stress is correlated to intention to quit among male nurses. Role stress and years of service are highly relevant predictors of male nurse intention to quit and leave the nursing profession, explaining 33.8% of variability. We suggest that at various levels of education and society, promotion of male and female equality should be increased. There is also a need for psychological consultation as well as the promotion of male nurse role models to prevent male nurses turning away from nursing careers.
- Published
- 2007
47. An in vitro analysis of ecdysteroid-elicited cell death in the prothoracic gland of Manduca sexta
- Author
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L. I. Gilbert and Ji-da Dai
- Subjects
medicine.medical_specialty ,Programmed cell death ,animal structures ,Histology ,DNA laddering ,Biology ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Internal medicine ,Endocrine Glands ,Manduca ,medicine ,In Situ Nick-End Labeling ,Animals ,Fragmentation (cell biology) ,Cells, Cultured ,Cell Nucleus ,Ecdysteroid ,TUNEL assay ,Cell Death ,fungi ,Cell Biology ,DNA ,Prothoracic gland ,biology.organism_classification ,Cell biology ,Microscopy, Electron ,Endocrinology ,Ecdysterone ,chemistry ,Apoptosis ,Manduca sexta - Abstract
The prothoracic glands of the tobacco hornworm, Manduca sexta, secrete the precursor of the insect molting hormone and normally undergo programmed cell death (PCD) during pupal-adult metamorphosis, between days 5 and 6 after pupation. This phenomenon can be elicited prematurely in vitro by the addition of 20-hydroxyecdysone (20E) to the gland cultures. To induce nuclear condensation in vitro in the glands from day-1 pupae, the effective dose range of 20E is 0.7-7 micrograms/ml and the minimum exposure period is 24 h. Prothoracic glands from different stages of pupal-adult development express different responsiveness to exogenous ecdysteroids. By utilizing terminal deoxynucleotidyl-transferase-mediated dUTP nick-end-labeling (TUNEL) and the apoptotic DNA laddering method together with transmission electron microscopy, it has been demonstrated that the ecdysteroid-induced cell death of the prothoracic glands occurs via not only apoptosis but also autophagy, i.e., the induced dying cells show both severe nuclear fragmentation and autophagic vacuole formation, characteristics typical of apoptotic and autophagic cell death. The composite data indicate that ecdysteroids regulate directly both apoptotic and autophagic mechanisms of PCD of the prothoracic glands.
- Published
- 1999
48. Can the insect nervous system synthesize ecdysteroids?
- Author
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James T. Warren, Ji-da Dai, and Lawrence I. Gilbert
- Subjects
Nervous system ,medicine.medical_specialty ,animal structures ,Tritium ,Biochemistry ,Nervous System ,chemistry.chemical_compound ,Internal medicine ,Manduca ,Hemolymph ,medicine ,Animals ,Molecular Biology ,Ecdysteroid ,biology ,fungi ,Ecdysteroids ,biology.organism_classification ,Cell biology ,Sterols ,medicine.anatomical_structure ,Endocrinology ,Drosophila melanogaster ,chemistry ,Manduca sexta ,Insect Science ,Peripheral nervous system ,Isotope Labeling ,Steroids ,Neural development ,Ecdysone - Abstract
The term “neurosteroid” refers to both classic and unique steroid molecules that are synthesized from cholesterol (C) by the central and peripheral nervous systems of higher vertebrates. Therein, they accumulate and modulate nervous activity by a variety of mechanisms other than the classic steroid receptor-mediated modulation of genomic activity, although such may also be involved. Since the insect nervous system expresses ecdysteroid receptors and responds both directly and developmentally to ecdysteroids, the possibility of ecdysteroidogenesis in the pupal and adult central and peripheral nervous system of Manduca sexta and the nervous system of Drosophila melanogaster larvae was investigated. The endogenous concentrations of the critical, dietary-derived Δ 5,7 -sterols ergosterol and 7-dehydrocholesterol (7dC) remained 10 to 20-fold higher in the Manduca pupal and adult nervous tissues than was found in the larval hemolymph at the cessation of feeding. In addition, it was determined that the Manduca pupal nervous system, but not that of the adult, could synthesize 3 H/ 14 C-7dC or 3 H-7-dehydro-25-hydroxycholesterol ( 3 H-7d25C) from 3 H/ 14 C-cholesterol ( 3 H/ 14 C-C) or the polar sterol substrate 3 H-25-hydroxycholesterol ( 3 H-25C), respectively. However, none of the nervous system samples from the two species and the several stages analyzed, a small window of neural development in these insects, were capable of incorporating any of the above tracer precursor sterols into a radiolabelled ecdysteroid, i.e. less than 0.0005%. Thus, the absence of neurosteroidogenesis by the insect nervous system stands in sharp contrast to previously described nervous system steroid hormone biosynthesis by the mammalian nervous system.
- Published
- 1999
49. Juvenile hormone prevents the onset of programmed cell death in the prothoracic glands of Manduca sexta
- Author
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Ji-da Dai and Lawrence I. Gilbert
- Subjects
medicine.medical_specialty ,Programmed cell death ,animal structures ,Apoptosis ,DNA Fragmentation ,DNA laddering ,Endocrinology ,stomatognathic system ,Internal medicine ,Endocrine Glands ,Manduca ,medicine ,Animals ,biology ,Endoplasmic reticulum ,fungi ,Metamorphosis, Biological ,Pupa ,Ecdysteroids ,biology.organism_classification ,Prothoracic gland ,Juvenile Hormones ,Manduca sexta ,Insect Hormones ,Juvenile hormone ,DNA fragmentation ,Animal Science and Zoology ,Steroids - Abstract
During normal pupal-adult development, programmed cell death of the prothoracic gland of Manduca sexta proceeds via apoptosis. By employing the DNA laddering technique, the earliest sign of DNA fragmentation in the cells comprising the gland occurred on Day 5 of pupal-adult development and DNA fragmentation peaked 1 day later. Since juvenile hormone (JH) is known to prevent adult development and since prothoracic gland degeneration occurs during the initial stages of adult development, we wished to determine the possible role of JH in prothoracic gland maintenance. JH was injected into pupae and the glands analyzed by DNA laddering and in situ TUNEL labeling. The administration of JH prevented apoptosis of the prothoracic gland even 11 days after JH injection into young pupae. The prothoracic glands remained intact and their ability to synthesize ecdysteroids was maintained at a fairly active level as ascertained by radioimmunoassay after in vitro incubation. The control glands had degenerated by this time and were almost devoid of ecdysteroidogenesis capability. Ultrastructural analysis confirmed that JH-treated prothoracic gland cells were rescued from the apoptotic sequence, i.e., nuclear condensation, cytoplasmic budding, and cell fragmentation. They exhibited a preserved smooth endoplasmic reticulum and intercellular channel system typical of active prothoracic gland cells. The composite data suggest that JH can both maintain and stimulate the prothoracic gland. Therefore, during normal pupal-adult metamorphosis the absence of JH is prerequisite for both the initiation and completion of prothoracic gland degeneration.
- Published
- 1998
50. Differential incorporation of cholesterol and cholesterol derivatives into ecdysteroids by the larval ring glands and adult ovaries of Drosophila melanogaster: a putative explanation for the l(3)ecd1 mutation
- Author
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James T. Warren, Ji-da Dai, Lawrence I. Gilbert, and Jane S. Bachmann
- Subjects
Ecdysone ,Mutant ,Biology ,Tritium ,Biochemistry ,Halloween genes ,chemistry.chemical_compound ,Animals ,Molecular Biology ,chemistry.chemical_classification ,Ecdysteroid ,Ovary ,Wild type ,Ecdysteroids ,biology.organism_classification ,In vitro ,Sterols ,Enzyme ,Cholesterol ,Drosophila melanogaster ,chemistry ,Insect Science ,Insect Hormones ,Isotope Labeling ,Larva ,Female ,Steroids - Abstract
Studies in vitro revealed that intact ring glands of Drosophila melanogaster convert tritiated cholesterol (C) and 25-hydroxycholesterol (25C) via 7-dehydrocholesterol (7dC) and 7-dehydro-25-hydroxycholesterol (7d25C), respectively, to ecdysone (E) and 2-deoxyecdysone (2dE), while both intact and homogenized ovaries synthesize only 2dE from these precursors. Emulsified 7d25C was incorporated directly into ecdysteroids by these tissue preparations at a much greater rate than was 7d25C made in situ from 25C. To probe the basis of the biochemical defect in the ecdysteroid deficient conditional mutant ecdysoneless (ecd1), the differential incorporation into ecdysteroids of C (via 7dC), and particularly of 25C (via 7d25C), was measured relative to that observed after the incubation of 7d25C directly with both wild type and mutant tissues in vitro at 30 degrees C, the restrictive temperature. Both C and 25C were equally 7,8-dehydrogenated in situ to 7dC or 7d25C, respectively, by both wild type and mutant tissues at 30 degrees C. However, the rate of subsequent conversion of either of these delta 5,7-sterol intermediates synthesized in situ to ecdysteroids was reduced an average of 50% in the mutant tissues relative to the wild type. Yet, when emulsified 7d25C was incubated directly with either the wild type or mutant tissues at the restrictive temperature, the amplified rate of conversion of the freely available 7d25C to ecdysteroid by these tissues was identical. These data suggest that the defect in ecd1 tissue-mediated ecdysteroidogenesis does not involve a "hit" on any of the enzymes involved in either the 7,8-dehydrogenation of C or 25C or in the subsequent oxidation of 7d25C or 7dC to ecdysteroid. Rather, the mutation appears to affect the expression of a gene governing the translocation of delta 5,7-sterol intermediates from the subcellular compartment where they are synthesized and/or stored to the site of subsequent oxidation to ecdysteroid.
- Published
- 1996
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