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Influence of transition metal ions on multiferroic properties of lead-free NBT–BT ceramics

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Journal of Advanced Dielectrics 2019年第6期9卷 23-30页

作者： S.Shanmuga Sundari r.Dhanasekaran Crystal Growth Centre Anna University Chennai 600025 Tamil NaduIndia PSGr Krishnammal College for Women Peelamedu Coimbatore 641004 Tamil NaduIndia

Using the conventional solid-state reaction method,0.5 wt.%of MnO_(2)^(-),NiO^(-),Cr_(2)O_(3)-,Fe_(2)O_(3)-and Co_(2)O_(3)-added 0.94Na_(0.5)-Bi_(0.5)TiO_(3)(NBT)–0.06BaTiO_(3)(BT)ceramics were *** perovskite nature of the prepared ceramics was analyzed by powder XrD and the surface morphology was studied by means of *** dielectric analysis was carried out from room temperature to 350℃ at various frequencies and the diffusive transition at the dielectric maxima confirmed the relaxor nature of the *** of oxygen vacancies by the possible substitution of ferromagnetic impurities decreased the dielectric constant and piezoelectric constant(d_(33)).The co-existence of ferromagnetism and the ferroelectricity was observed in the Mn,Ni,Co and Cr-added NBT–BT *** magnetic force microscopy(MFM)analysis was carried out to study the ferromagnetic domains in the prepared ceramic.

关键词： Ceramics ferroelectricity piezoelectricity atomic force microscopy

Investigations of physicochemical properties of dusts generated in mechanical reclamation process of spent moulding sands with alkaline resins

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China Foundry 2014年第2期11卷 132-138页

作者： r.Dańko M.Holtzer J.Dańko AGH University of Science and Technology Faculty of Foundry Engineering

Mechanical reclamation processes of spent moulding sands generate large amounts of postreclamation dusts mainly containing rubbed spent binding agents and quartz dusts. The amount of postreclamation dusts, depending in the reclamation system effi ciency and the reclaim dedusting system, can reach 5%-10% in relation to the total reclaimed spent moulding sand. The proper utilization of such material is a big problem facing foundries these days. This study presents the results of investigations of physicochemical properties of post- reclamation dusts. All tested dusts originated from various Polish cast steel plants applying the mechanical reclamation process of moulding sands with alkaline resins, obtained from different producers. Different dusts, delivered from foundries, were tested to determine their chemical composition, granular characterization, physicochemical and energetic properties. Presented results confi rmed assumptions that it is possible to utilize dusts generated during mechanical reclamation of used sands with organic resins as a source of energy.

关键词： dust recycling environmental protection reclamation moulding and core sands energy

Enteric glia mediate neuronal outgrowth through release of neurotrophic factors

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Neural regeneration research 2012年第28期7卷 2165-2175页

作者： Christopher r. Hansebout Kiran reddy Donald Zhang Michel P. rathbone Department of Surgery (Neurosurgery Neuroscience and Neurobiology) McMaster University Health Sciences Centre HamiltonON L8S 4K1 Canada Hamilton Neurorestorative Group (NrG) McMaster University Health Sciences Centre Hamilton ON L8S 4K1 Canada Cleveland Clinic Spine Institute Cleveland OH 44195 USA Department of Medicine (Neurology Neurobiochemistry) McMaster University Health Sciences Centre Hamilton ON L8S 4K1 Canada

Previous studies have shown that transplanted enteric glia enhance axonal regeneration, reduce tissue damage, and promote functional recovery following spinal cord injury. However, the mechanisms by which enteric glia mediate these beneficial effects are unknown. Neurotrophic factors can promote neuronal differentiation, survival and neurite extension. We hypothesized that enteric glia may exert their protective effects against spinal cord injury partially through the secretion of neurotrophic factors. In the present study, we demonstrated that primary enteric glia cells release nerve growth factor, brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor over time with their concentrations reaching approximately 250, 100 and 50 pg/mL of culture medium respectively after 48 hours. The biological relevance of this secretion was assessed by incubating dissociated dorsal root ganglion neuronal cultures in enteric glia-conditioned medium with and/or without neutralizing antibodies to each of these proteins and evaluating the differences in neurite growth. We discovered that conditioned medium enhances neurite outgrowth in dorsal root ganglion neurons. Even though there was no detectable amount of neurotrophin-3 secretion using ELISA analysis, the neurite outgrowth effect can be attenuated by the antibody-mediated neutralization of each of the aforementioned neurotrophic factors. Therefore, enteric glia secrete nerve growth factor, brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor and neurotrophin-3 into their surrounding environment in concentrations that can cause a biological effect.

关键词： spinal cord injury dorsal root ganglia enteric glia neurotrophic factor neurite outgrowth regeneration cell culture immunohistochemistry central nervous system neuroregeneration

role of gap junctions between keratinocyte and melanocyte in melanogenesis

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Frontiers in Biology 2015年第6期10卷 495-502页

作者： Divya Padma Kapaettu Satyamoorthy Kumar M.r. Bhat Division of Biotechnology School of Life Sciences Manipal University Manipal-576104 India Department of Anatomy Kasturba Medical College Manipal University Manipal-5 76104 India

The process ofmelanogenesis in melanocytes and the transport of melanin in the form ofmelanosomes to the neighboring keratinocytes are the key steps in human skin pigmentation. Keratinocytes and melanocytes interact in intricate manner to maintain the homeostasis. The present study was designed to understand the role of cell-cell interaction through the gap junctions between melanocytes and keratinocytes on melanogenesis. We show that, inhibition of the gap junctional activity between human keratinocytes and melanocytes in a coculture system using gap junction blocker lowers the expression of key regulatory genes of melanogenesis such as tyrosinase and microphthalmia- associated transcription factor （MITF）. This was followed by concurrent decrease in tyrosinase protein levels and activity. Our results show the preliminary evidence for the regulation of melanogenesis in melanocytes through direct gap junctional communication by keratinocytes. Deciphering the mechanism and factors involved in the process would uncover the significance of gap junctions in melanogenesis.

关键词： melanocyte keratinocyte melanogenesis gap junctions cell communication

Alternative models for transgenerational epigenetic inheritance:Molecular psychiatry beyond mice and man

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World Journal of Psychiatry 2021年第10期11卷 711-735页

作者： Gary r Hime Sophie LA Stonehouse Terence Y Pang Department of Anatomy and Physiology The University of MelbourneParkville 3010VICAustralia Mental Health Theme The Florey Institute of Neuroscience and Mental HealthParkville 3052VICAustralia

Mental illness remains the greatest chronic health burden globally with few inroads having been made despite significant advances in genomic knowledge in recent *** field of psychiatry is constantly challenged to bring new approaches and tools to address and treat the needs of vulnerable individuals and subpopulations,and that has to be supported by a continuous growth in *** majority of neuropsychiatric symptoms reflect complex geneenvironment interactions,with epigenetics bridging the gap between genetic susceptibility and environmental stressors that trigger disease onset and drive the advancement of *** has more recently been demonstrated in preclinical models that epigenetics underpins the transgenerational inheritance of stressrelated behavioural phenotypes in both paternal and maternal lineages,providing further supporting evidence for heritability in ***,unbiased prospective studies of this nature are practically impossible to conduct in humans so preclinical models remain our best option for researching the molecular pathophysiologies underlying many neuropsychiatric *** rodents will remain the dominant model system for preclinical studies(especially for addressing complex behavioural phenotypes),there is scope to expand current research of the molecular and epigenetic pathologies by using invertebrate ***,we will discuss the utility and advantages of two alternative model organisms–Caenorhabditis elegans and Drosophila melanogaster-and summarise the compelling insights of the epigenetic regulation of transgenerational inheritance that are potentially relevant to human psychiatry.

关键词： Transgenerational inheritance Epigenetics Invertebrate models Caenorhabditis elegans Drosophila melanogaster Environmental stress

NUMErICAL SIMULATION OF HUMAN AIr BrEATHING NEAr THE NOSE OUTLET

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Journal of Hydrodynamics 1999年第3期11卷 105-110页

作者： Ma Heng Buji People′s Hospital, Shengzhen 518112, P.r.China An Yi ran, Zhuang Ning Department of Mechanics, Peking University, Beijing 100871, P.r.China Yan Dong Beijing Zhongguancun Hospital, Beijing 100080, P.r.China (received Dec. 30, 1998

Numerical method is used to simulate the air breathing near the outlet of human nose. The process of breathing is visualized. The distribution of the exhausted air density may be useful in designing the medical equipm... 详细信息

关键词： human breathing N S equations air refreshing

Antioxidant activities of Indigofera cassioides *** various in vitro assay models

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Asian Pacific Journal of Tropical Biomedicine 2012年第4期2卷 256-261页

作者： r Senthil Kumar B rajkapoor P Perumal Natural Products Laboratory Swamy Vivekanandha College of Pharmacy Department of Pharmacology Dayanandha Sagar College of Pharmacy Department of Pharmaceutical Chemistry JKK Nataraja College of Pharmacy

Objective:To evaluate the antioxidant potential of methanolic leaf extract of Indigofera cassioides(MEIC) using various in vilro antioxidant assay ***:Antioxidant and free radical scavenging activity of MEIC was assayed by using different in vitro models like ABTS, DPPH,nitric oxide,superoxide,hydrogen peroxide and hydroxyl *** ability of the extract was tested by the complex formation with potassium *** total phenol and flavonoid contents of the crude extract were also *** and ascorbic acid were used as ***:MEIC exhibited potent and concentration dependent free radical scavenging activity in all the tested *** ability was also found to increase with increase in MEIC *** phenol and flavonoid content determination showed that the extract is rich in phenols and ***:All the results of the in vitro antioxidant assays reveal potent antioxidant and free radical scavenging activity of the leaves of Indigofera cassioides,equivalent to that of standard ascorbic acid and *** potent antioxidant activity may be attributed to its high phenolic and flavonoid contents.

关键词： Indigofera cassioides Antioxidant Free radicals Oxidative stress Total reducing power Free radical scavenging activity

Evaluation of forecasting methods from selected stock market returns

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Financial Innovation 2019年第1期5卷 724-739页

作者： M.Mallikarjuna r.Prabhakara rao Doctoral research Scholar Department of EconomicsSri Sathya Sai Institute of Higher LearningVidyagiriPrasanthi NilayamAPIndia

Forecasting stock market returns is one of the most effective tools for risk management and portfolio *** are several forecasting techniques in the literature for obtaining accurate forecasts for investment decision *** empirical studies have employed such methods to investigate the returns of different individual stock ***,there have been very few studies of groups of stock markets or *** findings of previous studies indicate that there is no single method that can be applied uniformly to all *** this context,this study aimed to examine the predictive performance of linear,nonlinear,artificial intelligence,frequency domain,and hybrid models to find an appropriate model to forecast the stock returns of developed,emerging,and frontier *** considered the daily stock market returns of selected indices from developed,emerging,and frontier markets for the period 2000–2018 to evaluate the predictive performance of the above *** results showed that no single model out of the five models could be applied uniformly to all ***,traditional linear and nonlinear models outperformed artificial intelligence and frequency domain models in providing accurate forecasts.

关键词： Financial markets Stock returns Linear and nonlinear Forecasting techniques root mean square error

The Sedimentary Sequence and Palaeogeographic Changes of the South Yellow Sea Since the Olduvai Subchron

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 195-207页

作者： Yang Zigeng Institute of Marine Geology, MGM r, Qingdao, Shandong Institute of Marine Geology MGMR Qingdao Shandong

According to the alternation of terrestrial beds and transgressive beds, the sedimentary sequence of the South Yellow Sea since the Olduvai subchron can be divided into 15 stratigraphical intervals. According to the facies analysis, there are 7 transgressive beds and one bed with transgression marks, and classical transgressive-regressive facies sequence also appears in the major transgressive *** evolution in the shelf area involved 4 periods: (1) 1.70-0.5 Ma B. P. was the stage for the development of the Palaeo-Yangtze river alluvial plain and delta. Tide influenced -river channel sediments formed during the Olduvai have been found in borehole QC2. The river mouth was located near 124°E and during the transgressive stage from 0.97-0.73 Ma B.P. to the east of 122.2°E, a large-scale undersea delta was formed. In the regressive stage, the shelf area became an alluvial plain. (2) 0.50-0.75 Ma B.P. was a multi-transgressive fluctuation stage during which 3 transgressive beds (HVI, HV, HIV)developed, being dated as 0.50-0.30 Ma B.P., 0.27-0.20 Ma B.P. and 127-75 Ka B.P. respectively, with the extent of transgression increasing gradually. Influenced by southeast monsoons, the eastern China continent began to have a larger moisture source. (3) 75-14 Ka B.P. was the lower sea-level stage during the last glacial period. The downcutting depth of rivers was up to -133 m. The palaeo-Yangtze river system flowed northeastwards into the Sea of Japan through the Sea of Japan through the Tsushima and Korean Straits. The interfluvial area became an eroded, weathered high land. In the cores, two short-lived, relatively high sea-level stages were recorded, corresponding to two interstades in the last glacial period. (4) The period since 14 Ka B.P. is the stage for 'Holocene transgression' and the development of the Yellow river-Huaihe river delta. Before 14 Ka the sea level rose to -68 m, and before 11 Ka to -50 m, and the sea-level was once at a standstill or slight

关键词： South Yellow Sea Quaternary sedimentary sequence palaeogeography