1,478 research outputs found

    PIV characterisation of flocculation dynamics and floc structure in water treatment

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    Particle flocculation with chemical flocculant addition is an essential step in water treatment. The performance of flocculation and the property of the flocs formed affect the overall results of the treatment process. In addition to particulate impurities, the presence of organic matter in water, such as natural organic materials (NOM), also influence the effectiveness of chemical flocculation. In this paper, the PIV system was employed to investigate the flocculation dynamics for different flocculants in different model waters. With the PIV and image analysis, the change in particle size distribution could be well recorded. Using the sequence of flocculation, shear breakage and re-flocculation on a jar-test device together with the PIV system, the rate of floc formation, the strength of the flocs, the recovery of broken flocs, and the morphological and structural features of the flocs were characterized. The results indicated that the adsorption of HA on the particle will stabilized the particles, hence hindered the flocculation process. Sweep flocculation using a higher chemical coagulant dosage was an effective means of process enhancement for the removal of particulates and associated organic matter. The dynamics of A-B-R process was characterized by particle size distribution (PSD) measurement with PIV setup. The particle strength and reversibility capability were examined. Strength index showed the HA flocs have comparable strength, while recovery index indicated a less recovery capability with the increasing of HA concentration after exposure to a higher shear, especially for ferric HA flocs. It appears that the bonds holding HA flocs together are not purely physical bonds given the limited regrowth seen. Finally, evolution of floc structure during A-B-R process was analysed by investigated the fractal dimension Db. The results were generally consistent with previous PSD measurements. It suggested that the structure of flocs in breakage became more compact with little permeability. An increase in floc compaction provides a further explanation for the limited regrowth for most of flocs. According to the performances of alum and ferric, it can be noticed that HA flocs have different properties dependent on which chemical coagulant is used. Alum produced larger HA flocs which endured a higher recovery capability after exploring higher shear, hence, compared to ferric, it could be preferred to using in the practical enhanced coagulation unit.postprin

    基于主成分分析法的空调系统传感器自动故障诊断

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    Author name used in this publication: 肖赋Author name used in this publication: WANG Sheng-wei (王盛卫)Author name used in this publication: 徐新华Title in Traditional Chinese: 基於主成分分析法的空調系統感應器自動故障診斷Journal title in Traditional Chinese: 建築科學2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    阿爾泰哈巴河群的沉積時代及其構造背景

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    Habahe Group mainly consists of elastic sediments, which widely distribute in the Chinese Altai and can provide important constraints on the tectonic evolution of the Central Asian Orogenic Belt (CAOB). However, there are different opinions about its deposition time and tectonic background. Previous studies suggested that the Habahe Group formed in Sinian to Mid-Ordovician or Mid- to Late Ordovician in a passive continental margin. On the other hand, recent geological investigations reveal a long lasting subduction-related setting in the Chinese Altai at least since Cambrian. The current geochronological study for detrital zircons from the Habahe Group reveals that the detrital zircons of individual samples, irrespective of their lithological and metamorphic differences, all show similar age patterns, with the early Paleozoic ( 206Pb/ 238U age = 463 ± 542Ma) grains predominating. The youngest detrital zircons from different samples display similar ages (ca. 470Ma), which may reflect the maximum deposition time of the Habahe Group. Dating of growth rim of detrital zircons from migmatite yielded a Mid-Devonian age (384 ± 6Ma), which was coeval with intrusion of Early to Mid-Devonian granitic plutons in the area and clearly indicates the minimum deposition time of the Hababe Group. Therefore, the deposition time of the Habahe Group can be constrained to be Mid-Ordovician to Early Devonian. Zircon U Pb dating results indicate that the detrital zircons of the Habahe Group are dominated by early Paleozoic grains, with small proportion formed in Precambrian. The early Paleozoic detrital zircons are mostly magmatic in origin, and their less rounded shapes indicate a limited transportation. The age and morphological characteristics of the detrital zircons are consistent with those of detrital zircons in active tectonic settings and indicate that the Chinese Altai was under an active continental margin environment during the Early Paleozoic. 北疆阿爾泰造山帶的哈巴河群變質碎屑巖分布廣泛,其沉積時代和構造環境對于認識中亞造山帶的演化歷史有重要意義。早期研究認為哈巴河群沉積于震旦紀—中奧陶世時期,形成于被動大陸邊緣構造環境。而最近有學者根據中亞造山帶的地質演化背景提出,阿爾泰形成于活動陸緣構造環境。對哈巴河群中碎屑鋯石的年代學研究表明,不同巖性或變質程度不同的樣品碎屑鋯石主要類群具有相似的年齡分布特征,其206Pb/238U 年齡主要介于463~542Ma 之間。在這些樣品中, 最年輕的碎屑鋯石年齡均集中于470Ma 左右,代表了碎屑沉積的時代下限。而哈巴河群混合巖樣品中碎屑鋯石增生邊形成于中泥盆世晚期(384±6Ma),與侵入該群的早古生代花崗巖的年齡十分接近,大致反映了哈巴河群碎屑巖沉積時代的上限,因此哈巴河群的沉積時代應在早泥盆世—中奧陶世之間。鋯石的形態和內部結構特征顯示哈巴河群的年輕碎屑鋯石類群(463~542Ma)主要為巖漿鋯石,其磨圓度較差,而且在比例上遠高于前寒武紀碎屑鋯石。上述特點與活動大陸邊緣碎屑鋯石類群分布特征完全一致,反映阿爾泰在中奧陶世至早泥盆世可能處于活動大陸邊緣構造環境。postprin

    Sexual Harassment Among Chinese Psychiatrists and Its Impact on Quality of Life: A Cross-Sectional Survey [Response to Letter]

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    Yu Xiao,1,2 Liang Liu,3 Ting-ting Chen,4 Zhou Zhang,5 Xiao-hong Wu6 1Psychosomatic Medical Center, The Fourth People’s Hospital of Chengdu, Chengdu, Sichuan Province, 610036, People’s Republic of China; 2Psychosomatic Medical Center, The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, 610036, People’s Republic of China; 3Department of Urology, Baoding No.1 Central Hospital, Baoding, Hebei Province, 071030, People’s Republic of China; 4Mental Health Center, West China Hospital of Sichuan University, Chengdu, Sichuan Province, 610044, People’s Republic of China; 5Department of Gastroenterology, Xiangyang No.1 People’s Hospital, Hubei University of Medicine, Xiangyang, Hubei Province, 441011, People’s Republic of China; 6Nursing Department, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, Affiliate Cancer Hospital of University of Electronic Science and Technology of China, Chengdu, Sichuan Province, 610041, People’s Republic of ChinaCorrespondence: Yu Xiao, Email [email protected]

    Sexual Harassment Among Chinese Psychiatrists and Its Impact on Quality of Life: A Cross-Sectional Survey

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    Yu Xiao,1,2 Liang Liu,3 Ting-ting Chen,4 Zhou Zhang,5 Xiao-hong Wu6 1Psychosomatic Medical Center, The Fourth People’s Hospital of Chengdu, Chengdu, Sichuan Province, 610036, People’s Republic of China; 2Psychosomatic Medical Center, The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, 610036, People’s Republic of China; 3Department of Urology, Baoding No.1 Central Hospital, Baoding, Hebei Province, 071030, People’s Republic of China; 4Mental Health Center, West China Hospital of Sichuan University, Chengdu, Sichuan Province, 610044, People’s Republic of China; 5Department of Gastroenterology, Xiangyang No.1 People’s Hospital, Hubei University of Medicine, Xiangyang, Hubei Province, 441011, People’s Republic of China; 6Nursing Department, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, Affiliate Cancer Hospital of University of Electronic Science and Technology of China, Chengdu, Sichuan Province, 610041, People’s Republic of ChinaCorrespondence: Yu Xiao, The Fourth People’s Hospital of Chengdu, No. 8, Huli West Lane 1, Yingmenkou Road, Chengdu, Sichuan Province, 610036, People’s Republic of China, Tel +86-028-85641749, Email [email protected]: Sexual harassment (SH) is a prevalent issue in various professional fields worldwide. The current study aims to investigate the incidence of SH targeting psychiatrists in China and explore its impact on quality of life (QOL).Methods: A consecutive recruitment of 1093 psychiatrists was conducted from 6 hospitals in China. The recorded data included participants’ socio-demographic characteristics, experiences of workplace SH within the previous year, and their QOL. SH comprised verbal harassment, physical harassment, and displaying of sexual organs. The Chinese version of the World Health Organization Quality of Life Brief Version (WHOQOL-BREF) was employed to assess QOL. We compared the demographic characteristics and QOL between the SH group and the non-SH group. Multiple logistic regression analysis was used to identify independent demographic correlates of SH.Results: In total, 13.8% (n = 151) of the psychiatrists reported SH, with 5.8% reporting it once, 4.4% reporting it twice, and 3.6% reporting it three times or more. Psychiatrists who had encountered SH exhibited lower QOL across social, psychological, physical, and environmental domains. Multiple logistic regression analysis revealed that young physicians and those with shorter work experience had a higher likelihood of experiencing SH.Conclusion: The high prevalence of SH among Chinese psychiatrists is of concern. Given its detrimental effects on the well-being of physicians and the quality of medical care they provide, it is crucial to develop specialized employee training programs for this population to effectively manage workplace SH.Keywords: China, psychiatrists, quality of life, mental health professionals, sexual harassment, workplace safet

    Molecular Cloning, Characterization, and Expression Analysis of an Estrogen Receptor-Related Receptor Homologue in the Cricket, Teleogryllus emma

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    The estrogen receptor-related receptors (ERRs) are a group of nuclear receptors that were originally identified on the basis of sequence similarity to estrogen receptors. The three mammalian ERR genes have been implicated in diverse physiological processes ranging from placental development to maintenance of bone density, but the function and regulation of ERRs in invertebrates are not well understood. A homologue of human ERR was isolated from the cricket Teleogryllus emma (Ohmachi and Matsumura) (Orthoptera: Gryllidae). The full-length cDNA of T. emma ERR, termed TeERR, has 1618 base pair (bp) and contains a 5′?-untranslated region of 140 bp and a 3′?-untranslated region of 272 bp. The open reading frame of TeERR encodes a deduced 401 amino acid peptide with a predicted molecular mass of 45.75 kilodaltons. The results of sequence alignments indicate that the TeERR protein shares an overall identity of 65%–82% with other known ERR homologues, and is most closely related to that of Nasonia vitripennis (Hymenoptera: Pteromalidae) and Apis mellifera (Apidae). Real-time quantitative reverse transcription-polymerase chain reaction was performed to compare the TeERR mRNA expression level at the whole body and gonad during T. emma development. The data revealed that TeERR mRNA is differentially expressed during T. emma development, with the highest expression level in embryos and the lowest in the body of late-instar larvae. The levels of TeERR transcripts also varied throughout gonad development; interestingly testicles had higher higher expression levels than ovaries at every development stage. These results suggest that TeERR has potential significance in the regulation of development in T. emma, due to its expression during different developmental periods

    Association Between Preoperative Sleep Disturbance and Postoperative Delirium in Elderly: A Retrospective Cohort Study

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    Hao Guo,1,* Li-Heng Li,2,* Xiao-Hong Lv,1,* Feng-Zhi Su,1,* Jie Chen,1,* Fei Xiao,1,3 Min Shi,1 Yu-Bo Xie1,3 1Department of Anesthesiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, People’s Republic of China; 2Department of Anesthesiology, The Guilin Municipal Hospital of Traditional Chinese Medicine, Guangxi, People’s Republic of China; 3Guangxi Key Laboratory of Enhanced Recovery after Surgery for Gastrointestinal Cancer, The First Affiliated Hospital of Guangxi Medical University, Nanning, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yu-Bo Xie, Department of Anesthesiology, The First Affiliated Hospital of Guangxi Medical University, No. 22 Shuangyong Road, Nanning, 530000, People’s Republic of China, Tel +86 13977121557, Email [email protected]: Postoperative sleep disturbance, characterized by diminished postoperative sleep quality, is a risk factor for postoperative delirium (POD); however, the association between pre-existing sleep disturbance and POD remains unclear. This study aimed to evaluate the association between preoperative sleep disturbance and POD in elderly patients after non-cardiac surgery.Patients and methods: This retrospective cohort study was conducted at a single center and enrolled 489 elderly patients who underwent surgery between May 1, 2020, and March 31, 2021. Patients were divided into the sleep disorder (SD) and non-sleep disorder (NSD) groups according to the occurrence of one or more symptoms of insomnia within one month or sleep- Numerical Rating Scale (NRS)≥ 6 before surgery. The primary outcome was the incidence of POD. Propensity score matching analysis was performed between the two groups. Multiple logistic regression analysis was performed to identify the risk factors for POD.Results: In both the unmatched cohort (16.0% vs 6.7%, P=0.003) and the matched cohort (17.0% vs 6.2%, P=0.023), the incidence of POD was higher in the SD group than in the NSD group. In addition, the postoperative sleep quality and the VAS score at postoperative 24 h were significantly lower in the SD group than in the NSD group. Multivariate logistic regression analysis indicated that age (Odds Ratio, 1.13 [95% CI: 1.04– 1.23], P=0.003) and preoperative sleep disturbance (Odds Ratio, 3.03 [95% CI: 1.09– 9.52], P=0.034) were independent risk factors for the development of POD.Conclusion: The incidence of POD was higher in patients with pre-existing sleep disturbance than those without it. Whether improving sleep quality for preoperative sleep disturbance may help prevent POD remains to be determined.Keywords: sleep disturbances, postoperative delirium, postoperative sleep quality, postoperative pain, anesthesi

    Rhabdastrellic Acid-A Induced Autophagy-Associated Cell Death through Blocking Akt Pathway in Human Cancer Cells

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    BACKGROUND: Autophagy is an evolutionarily conserved protein degradation pathway. A defect in autophagy may contribute to tumorigenesis. Autophagy inducers could have a potential function in tumor prevention and treatment. METHODOLOGY/PRINCIPAL FINDINGS: Our results showed that Rhabdastrellic acid-A, an isomalabaricane triterpenoid isolated from the sponge Rhabdastrella globostellata, inhibited proliferation of human cancer cell lines Hep3B and A549 and induced caspase-independent cell death in both the cell lines. Further investigation showed that Rhabdastrellic acid-A induced autophagy of cancer cells determined by YFP-LC3 punctation and increased LC3-II. The pretreatment with autophagy inhibitor 3-MA inhibited Rhabdastrellic acid-A-induced cell death. Knockdown of autophagy-related gene Atg5 inhibited Rhabdastrellic acid-A-induced cell death in A549 cells. Also, phospho-Akt and its downstream targets significantly decreased after treatment with Rhabdastrellic acid-A in both cancer cell lines. Transfection of constitutive active Akt plasmid abrogated autophagy and cell death induced by Rhabdastrellic acid-A. CONCLUSIONS/SIGNIFICANCE: These results suggest that Rhabdastrellic acid-A could induce autophagy-associated cell death through blocking Akt pathway in cancer cells. It also provides the evidence that Rhabdastrellic acid-A deserves further investigation as a potential anticancer or cancer preventive agent
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