In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of c...In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of climatic factors. This study was initiated to contribute to the sustainable and rational management of forest resources in the south-east of the Mono Biosphere Reserve in Togo. It specifically aims to identify and characterize the flora of the residual forest ecosystems within the reserve through their specific diversity, demographic structure, and carbon sequestration potential. The study was carried out in the forest ecosystems of Avévé. The methodology used was based on the analysis of phytosociological, forestry, ecological, and regeneration inventory data. Overall, the study revealed that the RBMT still has floristically viable habitats, despite the anthropogenic pressures it is subject to revealed a floristic diversity of 160 plant species divided into 52 families and 135 genera. The most represented families are Rubiaceae (29.09%), followed by Fabaceae (27.94%). The most represented species are Mitragyna inermis (Willd.) Kuntze (24.38%), Lecaniodiscus cupanioides Planch. Ex Benth (X) and Lonchocarpus sericeus (Poir.) Kunth (10.93%). The high presence of Mitragyna inermis observed in all the ecological groups identified makes it the characteristic species of the flooded marshy areas of southeast Togo and contributes to the resilience of the ecosystems and populations in the study area. The Shannon index for the formation groups varies between (3.03 and 5.16) bits. Pielou’s equitability varies between (0.43 and 0.63) bits. The overall average density is estimated at 210 stems/ha, with an average diameter of 25.57 ± 21.77 m and an average height of 7.93 ± 3.83 m. The adjustment of the diameter classes of the plant groups to the Weibull distribution gave an “inverted J” shape with coefficient values of less than 1 overall, reflecting the existence of multispecific or uneven-aged stands. Assessment of the horizontal and vertical structure shows a predominance of the shrub layer in all the groups identified. The carbon sequestration potential is 41.89 T/Ha. Despite ongoing anthropogenic pressures, the Mono Biosphere Reserve abounds in a relatively rich diversity of flora, the preservation of which is essential for the survival of biodiversity and even for the riparian population. The data provided by this study would form the basis for sustainable management planning of the forest islands in the biosphere reserve.展开更多
AIM: Tumor angiogenesis has been shown to be promoted by vascular endothelial growth factor (VEGF) via stimulating endothelial cell proliferation, migration, and survival. Blockade of VEGF signaling by different me...AIM: Tumor angiogenesis has been shown to be promoted by vascular endothelial growth factor (VEGF) via stimulating endothelial cell proliferation, migration, and survival. Blockade of VEGF signaling by different means has been demonstrated to result in reduced tumor growth and suppression of tumor angiogenesis in distinct tumor entities. Here, we tested a recombinant adenovirus, AdsFItl-3, that encodes an antagonistically acting fragment of the VEGF receptor 1 (Fit-l), for systemic antitumor effects in pre-established subcutaneous CRC tumors in mice.METHODS: Murine colorectal carcinoma cells (CT26) were inoculated subcutaneously into Balb/c mice for in vivo studies. Tumor size and survival were determined. 293 cell line was used for propagation of the adenoviral vectors. Human lung cancer line A549 and human umbilical vein endothelial cells were transfected for in vitro experiments.RESULTS: Infection of tumor cells with AdsFlt1-3 resulted in protein secretion into cell supernatant, demonstrating correct vector function. As expected, the secreted sFlt1-3 protein had no direct effect on CT26 tumor cell proliferation in vitro, but endothelial cell function was inhibited by about 46% as compared to the AdLacZ control in a tube formation assay. When AdsFlt1-3 (5×10^9 PFU/animal) was applied to tumor bearing mice, we found a tumor inhibition by 72% at d 12 after treatment initiation, in spite of these antitumoral effects, the survival time was not improved. According to reduced intratumoral microvessel density in AdsFlt1-3-treated mice, the antitumor mechanism can be attributed to angiostatic vector effects. We did not detect increased systemic VEGF levels after AdsFlt1-3 treatment and liver toxicity was low as judged by serum alanine aminotransferase determination.CONCLUSION: In this study we confirmed the value of a systemic administration of AdsFItl-3 to block VEGF signaling as antitumor therapy in an experimental metastatic colorectal carcinoma model in mice.展开更多
The identification of runoff generating areas (RGAs) within a watershed is a difficult task because of their temporal and spatial behavior. A watershed was selected to investigate the RGAs to determine the factors aff...The identification of runoff generating areas (RGAs) within a watershed is a difficult task because of their temporal and spatial behavior. A watershed was selected to investigate the RGAs to determine the factors affecting spatio-temporally in southern Ontario. The watershed was divided into 8 fields having a Wireless System Network (WSN) and a V-notch weir for flow and soil moisture measurements. The results show that surface runoff is generated by the infiltration excess mechanism in summer and fall, and the saturation excess mechanism in spring. The statistical analysis suggested that the amount of rainfall and rainfall intensity for summer (R2 = 0.63, 0.82) and fall (R2 = 0.74, 0.80), respectively, affected the RGAs. The analysis showed that 15% area generated 85% of surface runoff in summer, 100% of runoff in fall, and 40% of runoff in spring. The methodology developed has potential for identifying RGAs for protecting Ontario’s water resources.展开更多
Soil erosion is an important economic and environmental concern throughout the world. In order to assess soil erosion risk and conserve soil and water resources, soil erosion modeling at the watershed scale is imperat...Soil erosion is an important economic and environmental concern throughout the world. In order to assess soil erosion risk and conserve soil and water resources, soil erosion modeling at the watershed scale is imperative. The Guelph model for evaluating effects of Agricultural Management System on Erosion and Sedimentation (GAMES) is tailor-made for such applications;it, however, requires a significant amount of spatial information which needs to be pre-processed using a Geographic Information System (GIS). The GAMES model currently lacks any such automated tools. As such, the GAMES was loosely coupled to a GIS interface to manage the large spatial input data and to produce efficient cartographic representations of model output results. The developed interface tool was tested to simulate the Kettle Creek paired watershed in Southern Ontario, Canada. Result demonstrated that the GIS-assisted procedure increased the ability of the GAMES model in simulating such a spatially varied watershed and made the process more efficient and user-friendly. Furthermore, the quality of reporting and displaying resultant spatial output was also significantly improved. The developed GAMES interface could be applied to any watershed, and the enhancement could be used to assess soil erosion risk and conserve soil and water resources in an effective way.展开更多
Pringle Creek, identified as the source of dioxin/furan (PCDD/F) contamination to a Lake Ontario harbour was remediated in 2008. Surface sediment collected in 2013 near the floodplain remediation was no longer contami...Pringle Creek, identified as the source of dioxin/furan (PCDD/F) contamination to a Lake Ontario harbour was remediated in 2008. Surface sediment collected in 2013 near the floodplain remediation was no longer contaminated (∑<sub>17</sub>PCDD\Fs < 60 pg/g dw), but residual contamination extended downstream to the creek mouth (surface sediment maximum: ∑<sub>17</sub>PCDD\Fs 2900 pg/g dw). Nevertheless, sediment ∑<sub>17</sub>PCDD/F concentrations were lower in 2013 than pre-remediation suggesting that cleaner sediment was being deposited in the creek. Core data confirmed the decrease in sediment contamination through time since the most contaminated sediment was buried. Prior to the development of a remediation strategy for the harbour, the transport of bed-load and suspended sediment contaminated with PCDD/F was assessed. The challenge was the shallow water depth (0.6 m) throughout the creek thereby requiring non-standard sediment traps designed for this study. Suspended sediment collected in traps in 2014 showed residual contamination at the remediated site (∑<sub>17</sub>PCDD\Fs: 380 pg/g dw;TEQ (TEF fish) < 0.6 pg/g), with concentrations increasing with distance downstream mirroring surface sediment: mean ∑17PCDD\Fs concentration for suspended sediment at the creek mouth was 2200 pg/g (SD 260 pg/g dw) indicating PCDD/F contributions to the harbour. However, congener patterns in bottom sediment and suspended sediment near the remediated site and extending about 100 m downstream were similar to background upstream patterns consistent with atmospheric deposition as the source rather than the historical source which indicated that floodplain remedial actions were successful.展开更多
The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples rema...The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples remains challenging. Cr(VI) analyses with multipoint calibration and speciated isotope dilution (SID) adapted from U.S. EPA method 6800 were used to measure lower-level Cr(VI) on an ion chromatograph coupled with a tandem mass spectrometer (IC-MS/MS). Lake sediment samples were collected from various locations in Northern Ontario and Cr(VI) was extracted using both alkaline digestion and ethylene diaminetetraacetic acid (EDTA) extraction. Certified reference materials were extracted and analyzed by IC-MS/MS and UV-VIS detection. The SID-MS approach allowed for the quantification of Cr(VI) in samples with concentration levels below 0.5 μg.g-1 wet weight.展开更多
Hydrological monitoring and real-time access to data are valuable for hydrological research and water resources management. In the recent decades, rapid developments in digital technology, micro-electromechanical syst...Hydrological monitoring and real-time access to data are valuable for hydrological research and water resources management. In the recent decades, rapid developments in digital technology, micro-electromechanical systems, low power micro-sensing technologies and improved industrial manufacturing processes have resulted in retrieving real-time data through Wireless Sensor Networks (WSNs) systems. In this study, a remotely operated low-cost and robust WSN system was developed to monitor and collect real-time hydrologic data from a small agricultural watershed in harsh weather conditions and upland rolling topography of Southern Ontario, Canada. The WSN system was assembled using off-the-shelf hardware components, and an open source operating system was used to minimize the cost. The developed system was rigorously tested in the laboratory and the field and found to be accurate and reliable for monitoring climatic and hydrologic parameters. The soil moisture and runoff data for 7 springs, 19 summer, and 19 fall season rainfall events over the period of more than two years were successfully collected in a small experimental agricultural watershed situated near Elora, Ontario, Canada. The developed WSN system can be readily extended for the purpose of most hydrological monitoring applications, although it was explicitly tailored for a project focused on mapping the Variable Source Areas (VSAs) in a small agricultural watershed.展开更多
Trichloroethylene (TCE) is a chlorinated liquid that is commonly used for metal degreasing, household and industrial dry cleaning, and in paints and glues. Tetrachloroethylene, also known as perchloroethylene (PCE), i...Trichloroethylene (TCE) is a chlorinated liquid that is commonly used for metal degreasing, household and industrial dry cleaning, and in paints and glues. Tetrachloroethylene, also known as perchloroethylene (PCE), is an excellent solvent for organic materials. PCE is volatile, highly stable, non-flammable and widely used in dry cleaning. A new method has been developed for measuring TCE and PCE in ambient air in real-time. Based upon the chemical fingerprinting and concentration levels, the method was able to isolate the source of the emissions to the responsible facility. Real-time monitoring was accomplished by utilizing a low pressure chemical ionization source (LPCI) interfaced to a tandem mass spectrometer (TAGA). Monitoring the response of specific parent/daughter ion pairs, the TAGA was used to measure concentrations of TCE and PCE. By optimizing various TAGA parameters, detection limits (DL) as low as 0.5 μg/m3 was achieved for TCE and PCE. Unlike methods using cartridge sampling and GC/MS analysis, this new method provides a real time measurement for a wide range of TCE and PCE concentrations. This unique method was applied in 2000 and 2002 to measure TCE emitted from a manufacturer of stainless steel tubing in Eastern Ontario. The maximum half-hour average concentration of TCE measured downwind of the facility was 1300 μg/m3 and the maximum instantaneous level was measured at 115,000 μg/m3. The information collected by the TAGA unit was used by the Standard Development Branch of Ontario Ministry of the Environment to adopt the half-hour Point of Impingement (POI) standard of TCE to be 36 μg/m3 in 2010. This method successfully identified and simultaneously measured TCE and PCE during a 2011 air monitoring survey of a hazardous waste disposal and treatment facility in Southern Ontario.展开更多
A new in situ treatment technique was being utilized on a part of the Dorfweiher landfill in Konstanz, Germany to reduce the aftercare period. From 2010 to 2012, the landfill was aerated intermittently with low pressu...A new in situ treatment technique was being utilized on a part of the Dorfweiher landfill in Konstanz, Germany to reduce the aftercare period. From 2010 to 2012, the landfill was aerated intermittently with low pressure. Outgoing air was treated passively in an open biofilter which covers the landfill surface. The landfill was aerated by means of 80 air injection wells arranged area-wide in a 10 m grid. An elaborate measuring process and technological controls are being utilized in the pilot scheme. The data collected offer interesting insights about the processes during aeration, allowing optimization of the aeration strategy depending on changes of the conditions in the landfill. During the three-year aeration phase, conditions have changed inside the landfill section in various ways. In numerous zones of the landfill body, the aeration caused aerobic conditions with a decline of methane production. Accelerated settlings are measured up to 11%. The effects of the aerobic stabilization on the landfill are evaluated in a two-year monitoring phase started in 2013.展开更多
To develop mitigation and adaptation strategies for undesired consequences of climate change, it is important to understand the changing hydrological and climatological trends in the past few decades. Although the cha...To develop mitigation and adaptation strategies for undesired consequences of climate change, it is important to understand the changing hydrological and climatological trends in the past few decades. Although the changing climate is a cause of concern for the entire planet, its effects can vary significantly on a regional scale. Canada has experienced a rapid rise in the annual mean surface air temperature in the past decades. The current study aims to investigate trends in monthly mean precipitation, rainfall, snowfall, maximum and minimum temperature, as well as baseflow, surface runoff, and total streamflow values for the province of Ontario, Canada. To the best of the author’s knowledge, a similar study involving rural and urban watersheds, that quantifies the impact of changing climate on temperature and other hydrological processes over a period ranging from 1968 to 2017, has not yet been conducted for Ontario. Man-Kendall trend test was used to analyze trends in the above mentioned climatic and hydrometric parameters for rural and urban watersheds situated in the northern and southern parts of Ontario. The results of this study indicate that the mean monthly minimum temperatures for rural watersheds situated in southern Ontario have increased significantly for the winter and summer months, which may have caused an increase in snowmelt and consequently the streamflow for the winter months in the region. Unlike the watersheds in southern Ontario, the northern watersheds witnessed relatively fewer instances of significant changes in mean monthly temperatures, and in some cases, declining rates have been noted. Similarly, only a few watersheds in the north saw a substantial drop in baseflow over the summer months. For nearly all the months, the average monthly minimum and maximum temperatures were found to increase for urban watersheds. The streamflow, baseflow, and surface runoff increased, likely due to rapid urbanization, resulting in a lower infiltration rate. These results will contribute towards the decision-making processes and development of alternate water management policies within the province, taking into account the regional variations in climate change’s impact on the hydrology of Ontario’s watersheds.展开更多
Three tributaries of the Grand River watershed (Ontario, Canada), each representing different watershed types (urban, agricultural/rural, and mixed land-use) were examined to understand the spatial, temporal, and host...Three tributaries of the Grand River watershed (Ontario, Canada), each representing different watershed types (urban, agricultural/rural, and mixed land-use) were examined to understand the spatial, temporal, and host-source distribution of the waterborne pathogen, Cryptosporidium. Cryptosporidium was frequently found throughout the study (73%, 65/89) with occurrence and concentrations observed to be similar among the varying watershed types. However, applying advanced genotyping techniques, marked differences in dominant host sources could be observed in each watershed. The agricultural/rural and mixed land-use watersheds were dominated by genotypes typically associated with cattle (i.e., C. andersoni), while the urban watershed had the highest diversity of Cryptosporidium genotypes with a variety of wildlife as the common source of contamination (e.g., muskrat and cervine genotypes). A similar seasonal trend observed in the urban, agricultural, and mixed land-use watershed suggests that factors beyond specific land use activities (e.g. autumn manure spreading) may influence the timing and concentration of Cryptosporidium in these streams. Corresponding genotyping results provided additional insight into source inputs during these seasonal peaks, indicating that wildlife may be important seasonal contributors to Cryptosporidium contamination in these streams. Despite the abundance of Cryptosporidium in these watersheds, most of the genotypes observed were of limited human health importance. This study provides evidence regarding the significance of including genotyping results into studies examining waterborne Cryptosporidium. Using this technique can provide a greater understanding of the risk to the population using water sources, as well as provide insight into the probable sources and timing of contamination. This ancillary information can contribute to implementation of targeted management strategies to further protect sources of drinking water and recreation areas.展开更多
Project Trackdown is an investigative environmental program aimed at tracking sources of polychlorinated biphenyl (PCB) contamination in Great Lakes tributaries. The program uses a multimedia weight of evidence approa...Project Trackdown is an investigative environmental program aimed at tracking sources of polychlorinated biphenyl (PCB) contamination in Great Lakes tributaries. The program uses a multimedia weight of evidence approach for identifying sources of PCBs to the environment. PCB concentrations in environmental media (sediment, water, suspended sediment and soil), passive samplers and/or exposed biota (mussels, young-of-the-year fish and benthic invertebrates) are used in combination to evaluate bioavailability and identify local anomalies within a tributary. These lines of evidence can be assessed with simple chemometric techniques and fingerprinting of PCB congener profiles, and, combined with anecdotal information such as land use history and tributary alterations, may be used to identify ongoing and locally controllable sources of PCBs to the Great Lakes. The program was successful at developing environmental triggers to differentiate potential source areas from background PCB conditions in urban areas, allowing efforts to focus on identifying active ongoing sources of PCB contamination. Project Trackdown has been carried out in three tributaries to Lake Ontario (Cataraqui River, Etobicoke Creek and Twelve Mile Creek) and two tributaries that flow into the Detroit River (Turkey Creek and Little River). Local ongoing PCB sources have been identified in four projects, leading to abatement or remediation measures. As a collaborative initiative between the Ontario Ministry of the Environment and Environment Canada, Project Trackdown has successfully identified several PCB sources leading to substantial cleanup efforts aimed ultimately at reducing PCB contamination to the Great Lakes.展开更多
It is an established fact that huge quantities of water are lost from lakes, reservoirs and soils by evaporation. This assumes greater significance in arid and semi-arid regions around the globe when a general scarcit...It is an established fact that huge quantities of water are lost from lakes, reservoirs and soils by evaporation. This assumes greater significance in arid and semi-arid regions around the globe when a general scarcity of water is compounded by high evaporation loss from the open water surfaces of lakes and reservoirs. The use of surface covering by a monomolecular film to reduce evaporation loss from large open water surfaces offers the greatest promise among all currently available techniques. This is the only system that retains the water surface in a state that does not interfere with other uses of the body of water such as boating, navigation recreation, fish, and wildlife propagation. Various experiments and field trials worldwide have proven conclusively that the fatty alcohols and their emulsions effectively retard water evaporation and result in saving to the tune of about 20% to 50%. An experiment was carried out at the Aji Reservoir (India) using a mixture of Cetyl and Stearyl alcohol that confirmed 19.26% saving in evaporation loss. During this six-month trial, about 0.18 mcum of water was saved which otherwise might have evaporated.展开更多
This investigation was made to estimate current normal concentrations of total mercury in the hair of Chinese coastal people. Hair samples were collected from 659 healthy inhabitants in the areas along the coast and t...This investigation was made to estimate current normal concentrations of total mercury in the hair of Chinese coastal people. Hair samples were collected from 659 healthy inhabitants in the areas along the coast and the rivers (such as Shanghai, Ningbo, Dalian, Xiamen, and Zhoushan) of China from Feb. 2005 to June 2006. Total mercury concentrations in the samples were analyzed by the cold vapor atomic adsorption spectrometry method (CVAAS). The results showed the geometric mean concentration of total mercur...展开更多
Intensifying human activity in the Yangtze River Basin(YRB) has substantially increased nutrient concentrations in the Yangtze River Estuary,leading to degradation of the coastal environment.Analysis of nutrient deter...Intensifying human activity in the Yangtze River Basin(YRB) has substantially increased nutrient concentrations in the Yangtze River Estuary,leading to degradation of the coastal environment.Analysis of nutrient determinations published over the past 50 years reveals a gradual decreasing trend in the concentrations and fluxes of dissolved silicate(DSi).However,both dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphate(DIP) concentrations have increased significantly since the 1970 s.The frequency and area covered by red tide outbreaks have increased greatly during this period,mainly due to changes in nutrient supply ratios [i.e.,N/P(DIN/DIP),N/Si(DIN/DSi),P/Si(DIP/DSi)].A strong correlation was found between the riverine DIN fluxes and the estimated DIN inputs from the major N sources,particularly fertilizers and atmospheric deposition.The data provide a comprehensive assessment of nutrients in the YRB and their ecological impacts and indicate a potentially significant influence of atmospheric deposition on DIN loadings and fluxes.展开更多
The present work involves an extensive analytical and toxicological description of a recently identified mixed halogenated carbazole found in sediment samples,1,8-dibromo-3,6-dichloro-9H-carbazole(BCCZ).Concentrations...The present work involves an extensive analytical and toxicological description of a recently identified mixed halogenated carbazole found in sediment samples,1,8-dibromo-3,6-dichloro-9H-carbazole(BCCZ).Concentrations and the relative effect potency(REP)were calculated for the target BCCZ in a set of stream sediments collected in 2008 in Ontario,Canada.The levels calculated for BCCZ as compared to those previously assessed for legacy persistent organic pollutants(POPs)in the same samples revealed a significant contribution of BCCZ to the total organic chemical contamination(<1%e95%;average 37%).The corresponding dioxin toxic equivalencies(TEQs)of BCCZ in the sediment extracts were estimated from experimental REP data.The experimental data presented supports the classification of this emerging halogenated chemical as a contaminant of emerging environmental concern.Although potential emission sources could not be identified,this study highlights the importance of on-going research for complete characterization of halogenated carbazoles and related compounds.展开更多
Today 42% (9 000 km2) of the area of Hesse is covered with forests. The total area of forests hasslightly increased since several years. But actually the forests adjacent to the conurbations of NorthernHesse in the vi...Today 42% (9 000 km2) of the area of Hesse is covered with forests. The total area of forests hasslightly increased since several years. But actually the forests adjacent to the conurbations of NorthernHesse in the vicinity of Kassel in particular and in the Rhein-Main Region surrounding Frankfurt are in a verydifficult position. There is big demand for land to be converted into settlements, infrastructure, etc., whilethere is increasing need for the protective and recreational functions of the forests. Therefore maintenance ofexisting forests and establishment of new forests are amongst the most important responsibilities of theforest authorities on regional and district level.展开更多
The use of biopsy plugs to sample fish muscle tissue for mercury analyses is a viable alternative to lethal sampling; however, the practice has yet to be widely implemented in routine monitoring due to concerns about ...The use of biopsy plugs to sample fish muscle tissue for mercury analyses is a viable alternative to lethal sampling; however, the practice has yet to be widely implemented in routine monitoring due to concerns about variability of mercury concentrations in fish muscle tissues. Here we examine distribution of mercury in fillets of four fish species(Walleye, Northern Pike, Smallmouth Bass and Lake Trout), suitability of left/right side of fillet for biopsy sampling, and appropriateness of re-using a biopsy punch. The results showed that average mercury concentrations in left and right fillets of fish are similar.Mercury concentrations in biopsy plug samples, taken from the anterior dorsal area of the fish fillet, were statistically equivalent to the mercury concentrations in homogenized fillets. There was no discernible cross contamination between samples when a biopsy punch was reused after washing in hot soapy water, and as such, biopsy punches can be recycled during sampling to reduce the sampling cost. If a tissue mass collected from a specific site on the fillet is insufficient, then we suggest sampling corresponding locations on the other fillet rather than sampling two adjacent sites on one fillet to obtain more tissue. The results presented here can improve the accuracy of fillet biopsy plug sampling,minimize fish mortality for mercury monitoring, and reduce labor and material costs in monitoring programs.展开更多
After the shock of the Great East Japan Earthquake on 11 March 2011, the issue of local sustainability is presently center stage in the Japanese political process, and educational and research values are imperative fo...After the shock of the Great East Japan Earthquake on 11 March 2011, the issue of local sustainability is presently center stage in the Japanese political process, and educational and research values are imperative for long-term cost savings, risk management, and clean, efficient energy generation. This study illustrates the Sustainable Campus Initiative approach at Keio University that students have been undertaking to make the campus more sustainable and resilient during post-disaster restoration. To unveil innovative recovery concepts, processes, and social challenges, several outcomes that maximize energy efficiency and conservation opportunities are discussed. The results indicate that the Sustainable Campus Initiative contributed to energy relief in the summer of 2011. It made campus life more creative during a period when the 15 percent mandatory power-saving order by the government to big clients of Tokyo and Tohoku Electric was established. Pilot experiments provide a useful example of how the communications media have an extraordinary ability to increase public understanding of social issues. Since the March 11 disaster, power shortages have redirected renewed attention to fossil fuels. As large energy consumers, universities have an increased responsibility to demonstrate their commitment to sustainable design and encourage innovative development concepts in their regions in the future.展开更多
文摘In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of climatic factors. This study was initiated to contribute to the sustainable and rational management of forest resources in the south-east of the Mono Biosphere Reserve in Togo. It specifically aims to identify and characterize the flora of the residual forest ecosystems within the reserve through their specific diversity, demographic structure, and carbon sequestration potential. The study was carried out in the forest ecosystems of Avévé. The methodology used was based on the analysis of phytosociological, forestry, ecological, and regeneration inventory data. Overall, the study revealed that the RBMT still has floristically viable habitats, despite the anthropogenic pressures it is subject to revealed a floristic diversity of 160 plant species divided into 52 families and 135 genera. The most represented families are Rubiaceae (29.09%), followed by Fabaceae (27.94%). The most represented species are Mitragyna inermis (Willd.) Kuntze (24.38%), Lecaniodiscus cupanioides Planch. Ex Benth (X) and Lonchocarpus sericeus (Poir.) Kunth (10.93%). The high presence of Mitragyna inermis observed in all the ecological groups identified makes it the characteristic species of the flooded marshy areas of southeast Togo and contributes to the resilience of the ecosystems and populations in the study area. The Shannon index for the formation groups varies between (3.03 and 5.16) bits. Pielou’s equitability varies between (0.43 and 0.63) bits. The overall average density is estimated at 210 stems/ha, with an average diameter of 25.57 ± 21.77 m and an average height of 7.93 ± 3.83 m. The adjustment of the diameter classes of the plant groups to the Weibull distribution gave an “inverted J” shape with coefficient values of less than 1 overall, reflecting the existence of multispecific or uneven-aged stands. Assessment of the horizontal and vertical structure shows a predominance of the shrub layer in all the groups identified. The carbon sequestration potential is 41.89 T/Ha. Despite ongoing anthropogenic pressures, the Mono Biosphere Reserve abounds in a relatively rich diversity of flora, the preservation of which is essential for the survival of biodiversity and even for the riparian population. The data provided by this study would form the basis for sustainable management planning of the forest islands in the biosphere reserve.
基金Supported by the Deutsche Krebshilfe, No. 70-3065-SchmI
文摘AIM: Tumor angiogenesis has been shown to be promoted by vascular endothelial growth factor (VEGF) via stimulating endothelial cell proliferation, migration, and survival. Blockade of VEGF signaling by different means has been demonstrated to result in reduced tumor growth and suppression of tumor angiogenesis in distinct tumor entities. Here, we tested a recombinant adenovirus, AdsFItl-3, that encodes an antagonistically acting fragment of the VEGF receptor 1 (Fit-l), for systemic antitumor effects in pre-established subcutaneous CRC tumors in mice.METHODS: Murine colorectal carcinoma cells (CT26) were inoculated subcutaneously into Balb/c mice for in vivo studies. Tumor size and survival were determined. 293 cell line was used for propagation of the adenoviral vectors. Human lung cancer line A549 and human umbilical vein endothelial cells were transfected for in vitro experiments.RESULTS: Infection of tumor cells with AdsFlt1-3 resulted in protein secretion into cell supernatant, demonstrating correct vector function. As expected, the secreted sFlt1-3 protein had no direct effect on CT26 tumor cell proliferation in vitro, but endothelial cell function was inhibited by about 46% as compared to the AdLacZ control in a tube formation assay. When AdsFlt1-3 (5×10^9 PFU/animal) was applied to tumor bearing mice, we found a tumor inhibition by 72% at d 12 after treatment initiation, in spite of these antitumoral effects, the survival time was not improved. According to reduced intratumoral microvessel density in AdsFlt1-3-treated mice, the antitumor mechanism can be attributed to angiostatic vector effects. We did not detect increased systemic VEGF levels after AdsFlt1-3 treatment and liver toxicity was low as judged by serum alanine aminotransferase determination.CONCLUSION: In this study we confirmed the value of a systemic administration of AdsFItl-3 to block VEGF signaling as antitumor therapy in an experimental metastatic colorectal carcinoma model in mice.
文摘The identification of runoff generating areas (RGAs) within a watershed is a difficult task because of their temporal and spatial behavior. A watershed was selected to investigate the RGAs to determine the factors affecting spatio-temporally in southern Ontario. The watershed was divided into 8 fields having a Wireless System Network (WSN) and a V-notch weir for flow and soil moisture measurements. The results show that surface runoff is generated by the infiltration excess mechanism in summer and fall, and the saturation excess mechanism in spring. The statistical analysis suggested that the amount of rainfall and rainfall intensity for summer (R2 = 0.63, 0.82) and fall (R2 = 0.74, 0.80), respectively, affected the RGAs. The analysis showed that 15% area generated 85% of surface runoff in summer, 100% of runoff in fall, and 40% of runoff in spring. The methodology developed has potential for identifying RGAs for protecting Ontario’s water resources.
文摘Soil erosion is an important economic and environmental concern throughout the world. In order to assess soil erosion risk and conserve soil and water resources, soil erosion modeling at the watershed scale is imperative. The Guelph model for evaluating effects of Agricultural Management System on Erosion and Sedimentation (GAMES) is tailor-made for such applications;it, however, requires a significant amount of spatial information which needs to be pre-processed using a Geographic Information System (GIS). The GAMES model currently lacks any such automated tools. As such, the GAMES was loosely coupled to a GIS interface to manage the large spatial input data and to produce efficient cartographic representations of model output results. The developed interface tool was tested to simulate the Kettle Creek paired watershed in Southern Ontario, Canada. Result demonstrated that the GIS-assisted procedure increased the ability of the GAMES model in simulating such a spatially varied watershed and made the process more efficient and user-friendly. Furthermore, the quality of reporting and displaying resultant spatial output was also significantly improved. The developed GAMES interface could be applied to any watershed, and the enhancement could be used to assess soil erosion risk and conserve soil and water resources in an effective way.
文摘Pringle Creek, identified as the source of dioxin/furan (PCDD/F) contamination to a Lake Ontario harbour was remediated in 2008. Surface sediment collected in 2013 near the floodplain remediation was no longer contaminated (∑<sub>17</sub>PCDD\Fs < 60 pg/g dw), but residual contamination extended downstream to the creek mouth (surface sediment maximum: ∑<sub>17</sub>PCDD\Fs 2900 pg/g dw). Nevertheless, sediment ∑<sub>17</sub>PCDD/F concentrations were lower in 2013 than pre-remediation suggesting that cleaner sediment was being deposited in the creek. Core data confirmed the decrease in sediment contamination through time since the most contaminated sediment was buried. Prior to the development of a remediation strategy for the harbour, the transport of bed-load and suspended sediment contaminated with PCDD/F was assessed. The challenge was the shallow water depth (0.6 m) throughout the creek thereby requiring non-standard sediment traps designed for this study. Suspended sediment collected in traps in 2014 showed residual contamination at the remediated site (∑<sub>17</sub>PCDD\Fs: 380 pg/g dw;TEQ (TEF fish) < 0.6 pg/g), with concentrations increasing with distance downstream mirroring surface sediment: mean ∑17PCDD\Fs concentration for suspended sediment at the creek mouth was 2200 pg/g (SD 260 pg/g dw) indicating PCDD/F contributions to the harbour. However, congener patterns in bottom sediment and suspended sediment near the remediated site and extending about 100 m downstream were similar to background upstream patterns consistent with atmospheric deposition as the source rather than the historical source which indicated that floodplain remedial actions were successful.
文摘The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples remains challenging. Cr(VI) analyses with multipoint calibration and speciated isotope dilution (SID) adapted from U.S. EPA method 6800 were used to measure lower-level Cr(VI) on an ion chromatograph coupled with a tandem mass spectrometer (IC-MS/MS). Lake sediment samples were collected from various locations in Northern Ontario and Cr(VI) was extracted using both alkaline digestion and ethylene diaminetetraacetic acid (EDTA) extraction. Certified reference materials were extracted and analyzed by IC-MS/MS and UV-VIS detection. The SID-MS approach allowed for the quantification of Cr(VI) in samples with concentration levels below 0.5 μg.g-1 wet weight.
文摘Hydrological monitoring and real-time access to data are valuable for hydrological research and water resources management. In the recent decades, rapid developments in digital technology, micro-electromechanical systems, low power micro-sensing technologies and improved industrial manufacturing processes have resulted in retrieving real-time data through Wireless Sensor Networks (WSNs) systems. In this study, a remotely operated low-cost and robust WSN system was developed to monitor and collect real-time hydrologic data from a small agricultural watershed in harsh weather conditions and upland rolling topography of Southern Ontario, Canada. The WSN system was assembled using off-the-shelf hardware components, and an open source operating system was used to minimize the cost. The developed system was rigorously tested in the laboratory and the field and found to be accurate and reliable for monitoring climatic and hydrologic parameters. The soil moisture and runoff data for 7 springs, 19 summer, and 19 fall season rainfall events over the period of more than two years were successfully collected in a small experimental agricultural watershed situated near Elora, Ontario, Canada. The developed WSN system can be readily extended for the purpose of most hydrological monitoring applications, although it was explicitly tailored for a project focused on mapping the Variable Source Areas (VSAs) in a small agricultural watershed.
文摘Trichloroethylene (TCE) is a chlorinated liquid that is commonly used for metal degreasing, household and industrial dry cleaning, and in paints and glues. Tetrachloroethylene, also known as perchloroethylene (PCE), is an excellent solvent for organic materials. PCE is volatile, highly stable, non-flammable and widely used in dry cleaning. A new method has been developed for measuring TCE and PCE in ambient air in real-time. Based upon the chemical fingerprinting and concentration levels, the method was able to isolate the source of the emissions to the responsible facility. Real-time monitoring was accomplished by utilizing a low pressure chemical ionization source (LPCI) interfaced to a tandem mass spectrometer (TAGA). Monitoring the response of specific parent/daughter ion pairs, the TAGA was used to measure concentrations of TCE and PCE. By optimizing various TAGA parameters, detection limits (DL) as low as 0.5 μg/m3 was achieved for TCE and PCE. Unlike methods using cartridge sampling and GC/MS analysis, this new method provides a real time measurement for a wide range of TCE and PCE concentrations. This unique method was applied in 2000 and 2002 to measure TCE emitted from a manufacturer of stainless steel tubing in Eastern Ontario. The maximum half-hour average concentration of TCE measured downwind of the facility was 1300 μg/m3 and the maximum instantaneous level was measured at 115,000 μg/m3. The information collected by the TAGA unit was used by the Standard Development Branch of Ontario Ministry of the Environment to adopt the half-hour Point of Impingement (POI) standard of TCE to be 36 μg/m3 in 2010. This method successfully identified and simultaneously measured TCE and PCE during a 2011 air monitoring survey of a hazardous waste disposal and treatment facility in Southern Ontario.
文摘A new in situ treatment technique was being utilized on a part of the Dorfweiher landfill in Konstanz, Germany to reduce the aftercare period. From 2010 to 2012, the landfill was aerated intermittently with low pressure. Outgoing air was treated passively in an open biofilter which covers the landfill surface. The landfill was aerated by means of 80 air injection wells arranged area-wide in a 10 m grid. An elaborate measuring process and technological controls are being utilized in the pilot scheme. The data collected offer interesting insights about the processes during aeration, allowing optimization of the aeration strategy depending on changes of the conditions in the landfill. During the three-year aeration phase, conditions have changed inside the landfill section in various ways. In numerous zones of the landfill body, the aeration caused aerobic conditions with a decline of methane production. Accelerated settlings are measured up to 11%. The effects of the aerobic stabilization on the landfill are evaluated in a two-year monitoring phase started in 2013.
文摘To develop mitigation and adaptation strategies for undesired consequences of climate change, it is important to understand the changing hydrological and climatological trends in the past few decades. Although the changing climate is a cause of concern for the entire planet, its effects can vary significantly on a regional scale. Canada has experienced a rapid rise in the annual mean surface air temperature in the past decades. The current study aims to investigate trends in monthly mean precipitation, rainfall, snowfall, maximum and minimum temperature, as well as baseflow, surface runoff, and total streamflow values for the province of Ontario, Canada. To the best of the author’s knowledge, a similar study involving rural and urban watersheds, that quantifies the impact of changing climate on temperature and other hydrological processes over a period ranging from 1968 to 2017, has not yet been conducted for Ontario. Man-Kendall trend test was used to analyze trends in the above mentioned climatic and hydrometric parameters for rural and urban watersheds situated in the northern and southern parts of Ontario. The results of this study indicate that the mean monthly minimum temperatures for rural watersheds situated in southern Ontario have increased significantly for the winter and summer months, which may have caused an increase in snowmelt and consequently the streamflow for the winter months in the region. Unlike the watersheds in southern Ontario, the northern watersheds witnessed relatively fewer instances of significant changes in mean monthly temperatures, and in some cases, declining rates have been noted. Similarly, only a few watersheds in the north saw a substantial drop in baseflow over the summer months. For nearly all the months, the average monthly minimum and maximum temperatures were found to increase for urban watersheds. The streamflow, baseflow, and surface runoff increased, likely due to rapid urbanization, resulting in a lower infiltration rate. These results will contribute towards the decision-making processes and development of alternate water management policies within the province, taking into account the regional variations in climate change’s impact on the hydrology of Ontario’s watersheds.
文摘Three tributaries of the Grand River watershed (Ontario, Canada), each representing different watershed types (urban, agricultural/rural, and mixed land-use) were examined to understand the spatial, temporal, and host-source distribution of the waterborne pathogen, Cryptosporidium. Cryptosporidium was frequently found throughout the study (73%, 65/89) with occurrence and concentrations observed to be similar among the varying watershed types. However, applying advanced genotyping techniques, marked differences in dominant host sources could be observed in each watershed. The agricultural/rural and mixed land-use watersheds were dominated by genotypes typically associated with cattle (i.e., C. andersoni), while the urban watershed had the highest diversity of Cryptosporidium genotypes with a variety of wildlife as the common source of contamination (e.g., muskrat and cervine genotypes). A similar seasonal trend observed in the urban, agricultural, and mixed land-use watershed suggests that factors beyond specific land use activities (e.g. autumn manure spreading) may influence the timing and concentration of Cryptosporidium in these streams. Corresponding genotyping results provided additional insight into source inputs during these seasonal peaks, indicating that wildlife may be important seasonal contributors to Cryptosporidium contamination in these streams. Despite the abundance of Cryptosporidium in these watersheds, most of the genotypes observed were of limited human health importance. This study provides evidence regarding the significance of including genotyping results into studies examining waterborne Cryptosporidium. Using this technique can provide a greater understanding of the risk to the population using water sources, as well as provide insight into the probable sources and timing of contamination. This ancillary information can contribute to implementation of targeted management strategies to further protect sources of drinking water and recreation areas.
文摘Project Trackdown is an investigative environmental program aimed at tracking sources of polychlorinated biphenyl (PCB) contamination in Great Lakes tributaries. The program uses a multimedia weight of evidence approach for identifying sources of PCBs to the environment. PCB concentrations in environmental media (sediment, water, suspended sediment and soil), passive samplers and/or exposed biota (mussels, young-of-the-year fish and benthic invertebrates) are used in combination to evaluate bioavailability and identify local anomalies within a tributary. These lines of evidence can be assessed with simple chemometric techniques and fingerprinting of PCB congener profiles, and, combined with anecdotal information such as land use history and tributary alterations, may be used to identify ongoing and locally controllable sources of PCBs to the Great Lakes. The program was successful at developing environmental triggers to differentiate potential source areas from background PCB conditions in urban areas, allowing efforts to focus on identifying active ongoing sources of PCB contamination. Project Trackdown has been carried out in three tributaries to Lake Ontario (Cataraqui River, Etobicoke Creek and Twelve Mile Creek) and two tributaries that flow into the Detroit River (Turkey Creek and Little River). Local ongoing PCB sources have been identified in four projects, leading to abatement or remediation measures. As a collaborative initiative between the Ontario Ministry of the Environment and Environment Canada, Project Trackdown has successfully identified several PCB sources leading to substantial cleanup efforts aimed ultimately at reducing PCB contamination to the Great Lakes.
文摘It is an established fact that huge quantities of water are lost from lakes, reservoirs and soils by evaporation. This assumes greater significance in arid and semi-arid regions around the globe when a general scarcity of water is compounded by high evaporation loss from the open water surfaces of lakes and reservoirs. The use of surface covering by a monomolecular film to reduce evaporation loss from large open water surfaces offers the greatest promise among all currently available techniques. This is the only system that retains the water surface in a state that does not interfere with other uses of the body of water such as boating, navigation recreation, fish, and wildlife propagation. Various experiments and field trials worldwide have proven conclusively that the fatty alcohols and their emulsions effectively retard water evaporation and result in saving to the tune of about 20% to 50%. An experiment was carried out at the Aji Reservoir (India) using a mixture of Cetyl and Stearyl alcohol that confirmed 19.26% saving in evaporation loss. During this six-month trial, about 0.18 mcum of water was saved which otherwise might have evaporated.
文摘This investigation was made to estimate current normal concentrations of total mercury in the hair of Chinese coastal people. Hair samples were collected from 659 healthy inhabitants in the areas along the coast and the rivers (such as Shanghai, Ningbo, Dalian, Xiamen, and Zhoushan) of China from Feb. 2005 to June 2006. Total mercury concentrations in the samples were analyzed by the cold vapor atomic adsorption spectrometry method (CVAAS). The results showed the geometric mean concentration of total mercur...
基金supported by the National Natural Science Foundation of China (41705130)China Postdoctoral Science Foundation (2019T120156, 2018M641531)Beijing Advanced Discipline。
文摘Intensifying human activity in the Yangtze River Basin(YRB) has substantially increased nutrient concentrations in the Yangtze River Estuary,leading to degradation of the coastal environment.Analysis of nutrient determinations published over the past 50 years reveals a gradual decreasing trend in the concentrations and fluxes of dissolved silicate(DSi).However,both dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphate(DIP) concentrations have increased significantly since the 1970 s.The frequency and area covered by red tide outbreaks have increased greatly during this period,mainly due to changes in nutrient supply ratios [i.e.,N/P(DIN/DIP),N/Si(DIN/DSi),P/Si(DIP/DSi)].A strong correlation was found between the riverine DIN fluxes and the estimated DIN inputs from the major N sources,particularly fertilizers and atmospheric deposition.The data provide a comprehensive assessment of nutrients in the YRB and their ecological impacts and indicate a potentially significant influence of atmospheric deposition on DIN loadings and fluxes.
基金Authors thank Conservation Ontario and the Ministry of Northern Development and Mines for this project originated from the Ontario Ministry of Northern Development and Mines through the Southern Ontario Stream Sediment Project,a partnership between Ontario Ministry of the Environment and Climate Change,Ontario Ministry of Northern Development and Mines and Conservation Ontario.
文摘The present work involves an extensive analytical and toxicological description of a recently identified mixed halogenated carbazole found in sediment samples,1,8-dibromo-3,6-dichloro-9H-carbazole(BCCZ).Concentrations and the relative effect potency(REP)were calculated for the target BCCZ in a set of stream sediments collected in 2008 in Ontario,Canada.The levels calculated for BCCZ as compared to those previously assessed for legacy persistent organic pollutants(POPs)in the same samples revealed a significant contribution of BCCZ to the total organic chemical contamination(<1%e95%;average 37%).The corresponding dioxin toxic equivalencies(TEQs)of BCCZ in the sediment extracts were estimated from experimental REP data.The experimental data presented supports the classification of this emerging halogenated chemical as a contaminant of emerging environmental concern.Although potential emission sources could not be identified,this study highlights the importance of on-going research for complete characterization of halogenated carbazoles and related compounds.
文摘Today 42% (9 000 km2) of the area of Hesse is covered with forests. The total area of forests hasslightly increased since several years. But actually the forests adjacent to the conurbations of NorthernHesse in the vicinity of Kassel in particular and in the Rhein-Main Region surrounding Frankfurt are in a verydifficult position. There is big demand for land to be converted into settlements, infrastructure, etc., whilethere is increasing need for the protective and recreational functions of the forests. Therefore maintenance ofexisting forests and establishment of new forests are amongst the most important responsibilities of theforest authorities on regional and district level.
文摘The use of biopsy plugs to sample fish muscle tissue for mercury analyses is a viable alternative to lethal sampling; however, the practice has yet to be widely implemented in routine monitoring due to concerns about variability of mercury concentrations in fish muscle tissues. Here we examine distribution of mercury in fillets of four fish species(Walleye, Northern Pike, Smallmouth Bass and Lake Trout), suitability of left/right side of fillet for biopsy sampling, and appropriateness of re-using a biopsy punch. The results showed that average mercury concentrations in left and right fillets of fish are similar.Mercury concentrations in biopsy plug samples, taken from the anterior dorsal area of the fish fillet, were statistically equivalent to the mercury concentrations in homogenized fillets. There was no discernible cross contamination between samples when a biopsy punch was reused after washing in hot soapy water, and as such, biopsy punches can be recycled during sampling to reduce the sampling cost. If a tissue mass collected from a specific site on the fillet is insufficient, then we suggest sampling corresponding locations on the other fillet rather than sampling two adjacent sites on one fillet to obtain more tissue. The results presented here can improve the accuracy of fillet biopsy plug sampling,minimize fish mortality for mercury monitoring, and reduce labor and material costs in monitoring programs.
文摘After the shock of the Great East Japan Earthquake on 11 March 2011, the issue of local sustainability is presently center stage in the Japanese political process, and educational and research values are imperative for long-term cost savings, risk management, and clean, efficient energy generation. This study illustrates the Sustainable Campus Initiative approach at Keio University that students have been undertaking to make the campus more sustainable and resilient during post-disaster restoration. To unveil innovative recovery concepts, processes, and social challenges, several outcomes that maximize energy efficiency and conservation opportunities are discussed. The results indicate that the Sustainable Campus Initiative contributed to energy relief in the summer of 2011. It made campus life more creative during a period when the 15 percent mandatory power-saving order by the government to big clients of Tokyo and Tohoku Electric was established. Pilot experiments provide a useful example of how the communications media have an extraordinary ability to increase public understanding of social issues. Since the March 11 disaster, power shortages have redirected renewed attention to fossil fuels. As large energy consumers, universities have an increased responsibility to demonstrate their commitment to sustainable design and encourage innovative development concepts in their regions in the future.