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321.
Background of the studyThe genus Morinda of the Madder family, (Rubiaceae) has been widely documented in traditional medicine due to its therapeutic properties and also, contributed a great deal in chemical industry. Different parts of Morinda species have traditionally been used to treat malaria, diabetes, memory loss, cancer, inflammation, skin infections, and typhoid fever.Aim and ObjectivesThe review provide a critical and innovative information on the traditional uses, phytochemical constituents, and industrial applications of the genus Morinda. This will help researchers understand future research trends by bridging the gap between documented literature and contemporary uses.MethodologyAll the systematic literature data or information on the genus Morinda was collected via selected electronic databases, including Scopus, PubMed, Web of Science, Springer, Medline, ChemSpider, Taylor and Francis, Google Scholar, SciFinder, ScienceDirect and Wiley. Relevant book chapters, Wikipedia and books were also explored.ResultsThe study reveals that different parts of Morinda plants have been extensively used for folkloric therapeutic purposes and are a plethora of mineral or nutritional benefits and secondary metabolites. Several classes of bioactive compounds have been elucidated from Morinda plants via spectroscopic and chromatographic phytochemical analyses. Compounds such as terpenoids, glycosides, anthraquinones, polyphenols, steroids, saponins and reducing sugars are among the bioactive substances reported in the genus. Plant extracts, fractions and isolates of Morinda plants have exhibited pronounced antidiabetic, antioxidant, antiplasmodial, antidepressant, wound healing, anticancer, and anti-inflammatory effects (in vitro and in vivo). These pharmacological activities exhibited could be linked to the presence of secondary metabolites reported. The applications of this genus is well documented in textile, metallurgical, agrochemicals and food industries.ConclusionA number of reports on Morinda showed significant therapeutic effect against several diseases such as cancer, dermal infection, diabetes, inflammation, malaria, typhoid, cholera and memory loss, however, there were several drawback in previous reports including mechanism of action, drug dose, controls and toxicological data of extracts or isolates. In view of this, further studies should emphasis on targeting active secondary metabolites which responsible for the therapeutic activities, structural elucidation and toxicological assessment. Furthermore, industrial uses require authentication.  相似文献   
322.
Abstract

Effects of millipedes and earthworms on the decomposition of 15N-labelled litter of winter oilseed rape were investigated in a microcosm field experiment over a period of 264 days on an oat field near Göttingen managed by integrated farming.

A total of 32 microcosms were filled with defaunated soil. 15N-labelled rape litter was placed either on top of the soil or buried into the soil simulating mulching and ploughing, respectively. To the microcosms nine adult individuals of Blaniulus guttulatus (Diplopoda) and two of Aporrectodea caliginosa (Lumbricidae) were added separately or in combination.

In general, the presence of the animals accelerated the decomposition rate of the litter material. The effects were most pronounced in the presence of Aporrectodea caliginosa. The total amount of nitrate, ammonium and the amount of 15N leached from the microcosms was increased in the presence of earthworms or of both earthworms and millipedes. Both species proved to be important members of the detritus food web of the agricultural system studied.  相似文献   
323.
Ausgehend von den Arbeitsergebnissen und Arbeitsvorhaben des Zentralinstituts für Isotopen- und Strahlenforschung der AdW der DDR auf dem Gebiet der Spurenanalyse, der Erfassung lateraler Stoffverteilungen durch Abbildungsverfahren etc. werden einige Entwicklungstendenzen dargestellt. Dabei wird besonders auf solche Verfahren und Methoden eingegangen, die sich zur Erfassung von Stoffgehalten, flächenhaften und räumlichen Verteilungen von Spuren — wie sie z. B. in der Halbleiterindustrie, der Reinststoffuntersuchung und der Kernindustrie erforderlich sind — eignen.

Neben. den Grundprinzipien der Verfahren werden insbesondere ihre Anwendungsmöglichkeit, Nachweisempfindlichkeit, Leistungsfühigkeit etc. besprochen.  相似文献   
324.
An ultra-high-pressure liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method has been developed for the simultaneous quantification and confirmation of 11 basic/acidic illicit drugs and relevant metabolites in surface and urban wastewater at ng/L levels. The sample pre-treatment consisted of a solid-phase extraction using Oasis MCX cartridges. Analyte deuterated compounds were used as surrogate internal standards (except for norbenzoylecgonine and norcocaine) to compensate for possible errors resulting from matrix effects and those associated to the sample preparation procedure. After SPE enrichment, the selected drugs were separated within 6 min under UHPLC optimized conditions. To efficiently combine UHPLC with MS/MS, a fast-acquisition triple quadrupole mass analyzer (TQD from Waters) in positive-ion mode (ESI+) was used. The excellent selectivity and sensitivity of the TQD analyzer in selected reaction monitoring mode allowed quantification and reliable identification at the LOQ levels. Satisfactory recoveries (70–120%) and precision (RSD < 20%) were obtained for most compounds in different types of water samples, spiked at two concentration levels [limit of quantification (LOQ) and 10LOQ]. Thus, surface water was spiked at 30 ng/L and 300 ng/L (amphetamine and amphetamine-like stimulants), 10 ng/L and 100 ng/L (cocaine and its metabolites), 300 ng/L and 3000 ng/L (tetrahydrocannabinol-COOH). Recovery experiments in effluent and influent wastewater were performed at spiking levels of three and fifteen times higher than the levels spiked in surface water, respectively. The validated method was applied to urban wastewater samples (influent and effluent). The acquisition of three selected reaction monitoring transitions per analyte allowed positive findings to be confirmed by accomplishment of ion ratios between the quantification transition and two additional specific confirmation transitions. In general, drug consumption increased in the weekends and during an important musical event. The highest concentration levels were 27.5 μg/L and 10.5 μg/L, which corresponded to 3,4-methylenedioxymethamphetamine (MDMA, or ecstasy) and to benzoylecgonine (a cocaine metabolite), respectively. The wastewater treatment plants showed good removal efficiency (>99%) for low levels of illicit drugs in water, but some difficulties were observed when high drug levels were present in wastewaters.  相似文献   
325.
文章选择1999~2008年全国土地交易价格指数和房屋销售价格指数的季度数据作为样本,通过单位根检验和协整检验的基础上建立VAR模型,借助脉冲响应函数和方差分解进行实证研究,对进一步规范土地市场和房地产市场秩序提出建议.研究结果表明:地价与房价存在长期互动机制,房价对地价的影响大于地价对房价的影响.  相似文献   
326.
Air pollution monitoring includes measuring the concentrations of air contaminants such as nitrogen dioxide, sulfur dioxide, some polycyclic aromatic hydrocarbons(PAHs), suspended particulate matter (PM) and tar substances. The purpose of this study was to determine the possibility of using artificial neural networks for identification of any patterns occurring during heating and nonheating seasons. The samples included in the study were collected over a period of 5 years (1997–2001) in the area of the city of Gdansk and the levels of pollutants measured in the samples collected were used as inputs to two different types of neural networks: multilayer perceptron (MLP) and self-organizing map (SOM). The MLP was used as a tool to predict in what heating season a certain sample was collected, and the SOM was applied for mapping all samples to recognize any similarities between them. This study also presents the comparison between two projection methods—linear (principal component analysis, PCA) and nonlinear (SOM)—in extracting valuable information from multidimensional environmental data. In the research the MLP model with 13-12-1 topology was developed and successfully trained for classification of air samples from different seasons. The sensitivity analysis on the inputs to the MLP indicated benz[α]anthracene, benzo[α]pyrene, PM1, SO2, tar substances and PM10 as the most distinctive variables, while PCA pointed to PAHs and PM1.  相似文献   
327.
Factors influencing the sound preference in urban open spaces   总被引:1,自引:0,他引:1  
Lei Yu 《Applied Acoustics》2010,71(7):622-633
In this paper, based on a large scale survey in Europe and China as well as corresponding laboratory studies, the influencing factors on the sound preference evaluation, considering social, demographical, physical, behavioural and psychological facets, have been systematically examined based on statistical analyses for each of the 19 case study sites. Various sound types have been considered, including natural, human, mechanical and instrumental sounds. In terms of social/demographical factors, the results suggest that age and education level are two factors which universally influence the sound preference significantly, although the influence may vary with different types of urban open spaces and sounds. With increasing age or education level, people tend to prefer natural sounds and are more annoyed by mechanical sounds in general. It has also been found that gender, occupation and residence status generally would not influence the sound preference evaluation significantly, although gender has a rather strong influence for certain sound types such as bird sounds, especially at certain case study sites. In terms of physical factors (season, time of day), behavioural factors (frequency of coming to the site, reason for coming to the site), and psychological factors (site preference), generally speaking, their influence on the sound preference evaluation is insignificant, except for limited case study sites and certain sound types. The influence of home sound environment, in terms of sounds heard at home, on the sound preference has been found to be generally insignificant, except for certain sounds. It is noted that there are some correlations between social/demographical factors and the studied physical/behavioural/psychological factors, which should be taken into account when considering the influence of individual factors on sound preference.  相似文献   
328.
This paper compares two traffic representations for the assessment of urban noise frequency spectrum: (i) a static one, based on mean vehicle speeds and flow rates, (ii) a dynamic one, which considers vehicle interactions along the network. The two representations are compared on their suitability to match real on-field noise levels, recorded on a three lane quite busy street. Representation (i) fails in reproducing spectra envelopes that correspond to this site. In particular, it underestimates low frequencies, what can conceal the real impact of traffic flow on urban sound quality. Representation (ii) greatly improves estimation. It guarantees accurate environmental noise assessment, since it reproduces all traffic situations that are encountered in the site. Moreover, its 1s-based structure allows for the evaluation of spectra variations, with a good accuracy.  相似文献   
329.
基于GIS与虚拟现实技术的土地整理规划研究   总被引:1,自引:0,他引:1  
以湖北省赤壁市赤壁片土地整理规划为例,利用GIS(地理信息系统)与VR(虚拟现实技术)进行的土地整理规划,将实地测量数据在ArcGIS软件中进行数字化处理,采用GIS建立DEM(数字高程模型),同时将各种单体工程用三维制图软件3D MAX建模,并将3D模型嵌入在规划后的DEM中,获得规划后的虚拟场景,判断规划的合理性,同时对规划进行调整并加以完善.结果表明,基于GIS和VR技术进行土地整理规划,增强了规划后虚拟场景的仿真性,提高了土地整理规划结果的科学性.  相似文献   
330.
Inhalable aerosols collected in downtown Milan during a whole‐year field campaign (from November 2000 to October 2001) were investigated to determine amounts of n‐alkanes, polynuclear aromatic hydrocarbons (PAH), including benzo[a]pyrene (BaP), nitrated PAH (NPAH), and monocarboxylic n‐alkanoic acids. Combustion processes including vehicle emission were confirmed as the most important sources affecting air quality, whereas release of organic material from biota contributed a few percent. The occurrence of in‐situ reactions in the atmosphere promoted by oxidants modified, to some extent, the composition of both PAH and NPAH fractions, by reducing the amount of BaP present in the aerosols and increasing that of NPAH.  相似文献   
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