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101.
Several immunosuppressive factors are associated with parasitism of an endoparasitoid wasp, Cotesia plutellae, on the diamondback moth, Plutella xylostella. C. plutellae bracovirus (CpBV) encodes a large number of putative protein tyrosine phosphatases (PTPs), which may play a role in inhibiting
host cellular immunity. To address this inhibitory hypothesis of CpBV-PTPs, we performed transient expression of individual
CpBV-PTPs in hemocytes of the beet armyworm, Spodoptera exigua, and analyzed their cellular immune responses. Two different forms of CpBV-PTPs were chosen and cloned into a eukaryotic
expression vector under the control of the p10 promoter of baculovirus: one with the normal cysteine active site (CpBV-PTP1)
and the other with a mutated active site (CpBV-PTP5). The hemocytes transfected with CpBV-PTP1 significantly increased in
PTP activity compared to control hemocytes, but those with CpBV-PTP5 exhibited a significant decrease in the PTP activity.
All transfected hemocytes exhibited a significant reduction in both cell spreading and encapsulation activities compared to
control hemocytes. Co-transfection of CpBV-PTP1 together with its double-stranded RNA reduced the messenger RNA (mRNA) level
of CpBV-PTP1 and resulted in recovery of both hemocyte behaviors. This is the first report demonstrating that the polydnaviral
PTPs can manipulate PTP activity of the hemocytes to interrupt cellular immune responses. 相似文献
102.
Although Lebanon has abundant water, its rivers are polluted and aquifer water mismanaged. Effective river water usage requires an understanding of the geochemistry of polluting metals in catchments. Climate is “Mediterranean”: wet winters and dry summers. Active sediment flushing is restricted to winter high discharge episodes. Except in winter, water column pollutants are removed by precipitation or sorption to the surface of static bed sediments. Hence (1) does winter flushing of contaminated sediment and replacement by clean sediment favour self purification? (2) does the distribution of metals between extractable fractions change seasonally and thereby affect metal bioavailability ? Results on the distribution of metals are reported for Fe, Pb, Zn, Cu and Cd in bed sediments from Nahr Ibrahim (a karstic river) for summer and winter. A Tessier-like sequential extraction scheme was applied to samples (< 75 μm) for five locations along a 13 km stretch to the sea. Water pH was above 8.2 at all locations implying a very low solubility for Fe. Sediment was derived from catchment soils and limestone. Total sediment Fe increased in winter at all sites following deposition of eroded soil from upstream. Cadmium, Cu and Pb derived from polluting sources; the sources of Zn were more complex. Dilution by clean sediment explained winter reductions in total Cd, Cu and Pb; Zn changes were less consistent. Iron occurred mostly (> 77 sum of fractions) in the residual fraction compared with 6– 31 for pollutants; residual Cu and Zn showed a small increase in winter whereas Cd and Pb did not change. All readily exchangeable metals decreased in winter and the carbonate bound forms predominated in both seasons. Nahr Ibrahim has a high capacity for self purification and metal resolubilisation from sediment will be limited by the solubility of carbonate forms. 相似文献
103.
Over the last two decades, urban noise has been increasingrapidly, primarily in urban areas, due to population growthand the increase of certain noise sources. The main objectiveof this paper is to assess the sources and possible impactsof the community noise problems in Lebanese urban areas,particularly the Greater Beirut Area. The causes and effectsof community noise pollution are briefly presented. Soundpressure levels that were measured to define existing noiseexposure levels in various locations in the Greater BeirutArea are also presented. The attitudes toward noise pollutionand perceived annoyance impact on a sample of 1,038 exposedresidents are described. The association between measurednoise levels and sources, as well as annoyance, is examinedusing correlation analysis and linear and multiple linearregressions. A set of recommendations is presented to reducecommunity noise problem in Greater Beirut Area. 相似文献
104.
Christopher S. Jones Caroline A. Davis Chad W. Drake Keith E. Schilling Samuel H.P. Debionne Daniel W. Gilles Ibrahim Demir Larry J. Weber 《Journal of the American Water Resources Association》2018,54(2):471-486
Various techniques exist to estimate stream nitrate loads when measured concentration data are sparse. The inherent uncertainty associated with load estimation, however, makes tracking progress toward water quality goals more difficult. We used high‐frequency, in situ nitrate sensors strategically deployed across the agricultural state of Iowa to evaluate 2016 stream concentrations at 60 sites and loads at 35 sites. The generated data, collected at an average of 225 days per site, show daily average nitrate‐N yields ranging from 12 to 198 g/ha, with annual yields as high as 53 kg/ha from the intensely drained Des Moines Lobe. Thirteen of the sites that capture water from 82.5% of Iowa's area show statewide nitrate‐N loading in 2016 totaled 477 million kg, or 41% of the load delivered to the Mississippi–Atchafalaya River Basin (MARB). Considering the substantial private and public investment being made to reduce nitrate loading in many states within the MARB, networks of continuous, in situ measurement devices as described here can inform efforts to track year‐to‐year changes in nitrate load related to weather and conservation implementation. Nitrate and other data from the sensor network described in this study are made publicly available in real time through the Iowa Water Quality Information System. 相似文献
105.
Sharif Asmaa Fady AlAmeer Mahdi Riyadh AlSubaie Duhaim Saad Alarfaj Naser Husam AlDawsari Mubarak Khalifah AlAslai Khalid Mansour BuSaleh Mahmoud Jawad AlSabr Abdulaziz Ibrahim Al-Mulhim Khalid Abdulmohsen 《Environmental science and pollution research international》2021,28(43):60511-60525
Environmental Science and Pollution Research - Methanol intoxication is a global problem with serious morbidities and mortalities. Apart from the lifelong disabilities experienced by methanol... 相似文献
106.
Ali Guney M. Ibrahim Poyraz Olgac Kangal Firat Burat 《Waste management (New York, N.Y.)》2013,33(9):1795-1799
Plastics have become the widely used materials because of their advantages, such as cheapness, endurance, lightness, and hygiene. However, they cause waste and soil pollution and they do not easily decompose. Many promising technologies are being investigated for separating mixed thermoplastics, but they are still uneconomical and unreliable. Depending on their surface characteristics, these plastics can be separated from each other by flotation method which is useful mineral processing technique with its low cost and simplicity.The main objective of this study is to investigate the flotation characteristics of PET and PVC and determine the effect of plasticizer reagents on efficient plastic separation. For that purpose, various parameters such as pH, plasticizer concentration, plasticizer type, conditioning temperature and thermal conditioning were investigated. As a result, PET particles were floated with 95.1% purity and 65.3% efficiency while PVC particles were obtained with 98.1% purity and 65.3% efficiency. 相似文献
107.
Optimization of decolorization of palm oil mill effluent (POME) by growing cultures of Aspergillus fumigatus using response surface methodology 总被引:1,自引:1,他引:0
Chin Hong Neoh Adibah Yahya Robiah Adnan Zaiton Abdul Majid Zaharah Ibrahim 《Environmental science and pollution research international》2013,20(5):2912-2923
The conventional treatment process of palm oil mill effluent (POME) produces a highly colored effluent. Colored compounds in POME cause reduction in photosynthetic activities, produce carcinogenic by-products in drinking water, chelate with metal ions, and are toxic to aquatic biota. Thus, failure of conventional treatment methods to decolorize POME has become an important problem to be addressed as color has emerged as a critical water quality parameter for many countries such as Malaysia. Aspergillus fumigatus isolated from POME sludge was successfully grown in POME supplemented with glucose. Statistical optimization studies were conducted to evaluate the effects of the types and concentrations of carbon and nitrogen sources, pH, temperature, and size of the inoculum. Characterization of the fungus was performed using scanning electron microscopy, Fourier transform infrared (FTIR) spectroscopy, and Brunauer, Emmet, and Teller surface area analysis. Optimum conditions using response surface methods at pH 5.7, 35 °C, and 0.57 % w/v glucose with 2.5 % v/v inoculum size resulted in a successful removal of 71 % of the color (initial ADMI of 3,260); chemical oxygen demand, 71 %; ammoniacal nitrogen, 35 %; total polyphenolic compounds, 50 %; and lignin, 54 % after 5 days of treatment. The decolorization process was contributed mainly by biosorption involving pseudo-first-order kinetics. FTIR analysis revealed that the presence of hydroxyl, C–H alkane, amide carbonyl, nitro, and amine groups could combine intensively with the colored compounds in POME. This is the first reported work on the application of A. fumigatus for the decolorization of POME. The present investigation suggested that growing cultures of A. fumigatus has potential applications for the decolorization of POME through the biosorption and biodegradation processes. 相似文献
108.
Peter J. Peterson Mazlin bin Mokhtar Cheryl Chang Jonathan Krueger 《Journal of environmental management》2010,91(5):1202-1208
This paper briefly outlines the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and what is meant by GHS implementation in terms of policy-related information for decision-makers plus a framework of actions to enable such policies to be effectively undertaken. The paper discusses the need for simple indicators to measure progress with GHS implementation. Two groups of indicators have been described that comprehensively reflect basic components of GHS implementation. The first group was presented as aggregated indicators or indices, for national capability evaluation. Indicators to evaluate management performance linked to stated objectives were presented as the second group. Information from an Organisation for Economic Co-operation and Development (OECD) published questionnaire on GHS implementation and a questionnaire by the Intergovernmental Forum on Chemical Safety (IFCS) on chemical safety that included GHS have provided the basic information for applying the management capability indicators approach. Through the use of information in these two questionnaires, country-relevant and regional progress with GHS implementation was illustrated. Despite the GHS implementation target of 2008 set by the Johannesburg Plan of Implementation, very few countries have reported they have achieved this target. The simple management indicators proposed in this paper are based on adoption of a questionnaire and a numerical scoring system that could be used to chart progress towards GHS implementation. It was concluded, therefore, that the use of indicators as described in this paper does provide a quick survey of the overall situation in a country and facilitates comparison between countries across regions in terms of GHS implementation. Furthermore such results may indicate which countries require additional assistance with GHS implementation thus strengthening policies and actions across all sectors and involving governments, business, trade, and civil society. 相似文献
109.
Halil Ibrahim Inan Valentina Sagris Wim Devos Pavel Milenov Peter van Oosterom Jaap Zevenbergen 《Journal of environmental management》2010,91(12):2440-2454
The Common Agricultural Policy (CAP) of the European Union (EU) has dramatically changed after 1992, and from then on the CAP focused on the management of direct income subsidies instead of production-based subsidies. For this focus, Member States (MS) are expected to establish Integrated Administration and Control System (IACS), including a Land Parcel Identification System (LPIS) as the spatial part of IACS. Different MS have chosen different solutions for their LPIS. Currently, some MS based their IACS/LPIS on data from their Land Administration Systems (LAS), and many others use purpose built special systems for their IACS/LPIS. The issue with these different IACS/LPIS is that they do not have standardized structures; rather, each represents a unique design in each MS, both in the case of LAS based or special systems. In this study, we aim at designing a core data model for those IACS/LPIS based on LAS. For this purpose, we make use of the ongoing standardization initiatives for LAS (Land Administration Domain Model: LADM) and IACS/LPIS (LPIS Core Model: LCM). The data model we propose in this study implies the collaboration between LADM and LCM and includes some extensions. Some basic issues with the collaboration model are discussed within this study: registration of farmers, land use rights and farming limitations, geometry/topology, temporal data management etc. For further explanation of the model structure, sample instance level diagrams illustrating some typical situations are also included. 相似文献
110.
Chi Kim Lim Hui Han Bay Chin Hong Neoh Azmi Aris Zaiton Abdul Majid Zaharah Ibrahim 《Environmental science and pollution research international》2013,20(10):7243-7255
In this study, the adsorption behavior of azo dye Acid Orange 7 (AO7) from aqueous solution onto macrocomposite (MC) was investigated under various experimental conditions. The adsorbent, MC, which consists of a mixture of zeolite and activated carbon, was found to be effective in removing AO7. The MC were characterized by scanning electron microscopy (SEM), energy dispersive X-ray, point of zero charge, and Brunauer–Emmett–Teller surface area analysis. A series of experiments were performed via batch adsorption technique to examine the effect of the process variables, namely, contact time, initial dye concentration, and solution pH. The dye equilibrium adsorption was investigated, and the equilibrium data were fitted to Langmuir, Freundlich, and Tempkin isotherm models. The Langmuir isotherm model fits the equilibrium data better than the Freundlich isotherm model. For the kinetic study, pseudo-first-order, pseudo-second-order, and intraparticle diffusion model were used to fit the experimental data. The adsorption kinetic was found to be well described by the pseudo-second-order model. Thermodynamic analysis indicated that the adsorption process is a spontaneous and endothermic process. The SEM, Fourier transform infrared spectroscopy, ultraviolet–visible spectral and high performance liquid chromatography analysis were carried out before and after the adsorption process. For the phytotoxicity test, treated AO7 was found to be less toxic. Thus, the study indicated that MC has good potential use as an adsorbent for the removal of azo dye from aqueous solution. 相似文献