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141.
142.
The capability of a cost-effective and a small size decentralized pilot wastewater treatment plant (WWTP) to remove enteric viruses such as rotavirus, norovirus genogroup I (GGI), norovirus genogroup II (GGII), Hepatitis E virus (HEV), and adenovirus was studied. This pilot plant is an integrated hybrid anaerobic/aerobic setup which consisted of anaerobic sludge blanket (UASB), biological aerated filter (BAF), and inclined plate settler (IPS). Both the UASB and BAF are packed with a non-woven polyester fabric (NWPF). Results indicated that the overall log10 reductions of enteric viruses’ genome copies through the whole system were 3.1 ± 1, 3.3 ± 0.5, and 2.6 ± 0.9 log10 for rotavirus, norovirus GGI, and adenovirus, respectively. Reduction efficiency for both norovirus GGII and HEV after the different treatment steps could not be calculated because there were no significant numbers of positive samples for both viruses. The overall reduction of rotavirus infectious units through the whole system was 2.2 ± 0.8 log10 reduction which is very close to the overall log10 reduction of adenovirus infectious units through the whole system which was 2.1 ± 0.8 log10 reduction. There was no considerable difference in the removal efficiency for different rotavirus G and P types. Adenovirus 41 was the only type detected in the all positive samples. Although the pilot WWTP investigated is cost effective, has a small footprint, does not need a long distance network pipes, and easy to operate, its efficiency to remove enteric viruses is comparable with the conventional centralized WWTPs. 相似文献
143.
Mara C. Diguez Claudia P. Queimalios Sergio Ribeiro Guevar Mark Marvin-DiPasquale Carolina Soto Crdenas Mara A. Arribre 《环境科学学报(英文版)》2013,25(10):1980-1991
Ligands present in dissolved organic matter (DOM) form complexes with inorganic divalent mercury (Hg^2+) affecting its bioavailability in pelagic food webs. This investigation addresses the influence of a natural gradient of DOM present in Patagonian lakes on the bioaccumulation of Hg^2+ (the prevailing mercury species in the water column of these lakes) by the algae Cryptomonas erosa and the zooplankters Brachionus calyciflorus and Boeckella antiqua. Hg^2+ accumulation was studied through laboratory experiments using natural water of four oligotrophic Patagonian lakes amended with^197Hg^2+. The bioavailability of Hg^2+ was affected by the concentration and character of DOM. The entrance of Hg^2+ into pelagic food webs occurs mostly through passive and active accumulation. The incorporation of Hg^2+ by Cryptomonas, up to 27% of the Hg^2+ amended, was found to be rapid and dominated by passive adsorption, and was greatest when low molecular weight compounds with protein-like or small phenolic signatures prevailed in the DOM. Conversely, high molecular weight compounds with a humic or fulvic signature kept Hg^2+ in the dissolved phase, resulting in the lowest Hg^2+ accumulation in this algae. In Brachionus and Boeckella the direct incorporation of Hg from the aqueous phase was up to 3% of the Hg^2+ amended. The dietary incorporation of Hg^2+ by Boeckella exceeded the direct absorption of this metal in natural water, and was remarkably similar to the Hg^2+ adsorbed in their prey. Overall, DOM concentration and character affected the adsorption of Hg^2+ by algae through competitive binding, while the incorporation of Hg^2+ into the zooplankton was dominated by trophic or dietary transfer. 相似文献
144.
Maria Rönnqvist Thedi Ziegler Carl-Henrik von Bonsdorff Leena Maunula 《Food and environmental virology》2012,4(1):26-33
Recent events have shown that humans may become infected with some pathogenic avian influenza A viruses (AIV). Since soil
and water, including lakes, rivers, and seashores, may be contaminated by AIV excreted by birds, effective methods are needed
for monitoring water for emerging viruses. Combining water filtration with molecular methods such as PCR is a fast and effective
way for detecting viruses. The objective of this study was to apply a convenient method for the detection of AIV in natural
water samples. Distilled water and lake, river, and seawater were artificially contaminated with AIV (H5N3) and passed through
a filter system. AIV was detected from filter membrane by real-time RT-PCR. The performance of Zetapor, SMWP, and Sartobind
D5F membranes in recovering influenza viruses was first evaluated using contaminated distilled water. SWMP, which gave the
highest virus recoveries, was then compared with a pre-filter combined GF/F filter membrane in a trial using natural water
samples. In this study, the cellulose membrane SMWP was found to be practical for recovery of AIVs in water. Viral yields
varied between 62.1 and 65.9% in distilled water and between 1 and 16.7% in natural water samples. The borosilicate glass
membrane GF/F combined with pre-filter was also feasible in filtering natural water samples with viral yields from 1.98 to
7.33%. The methods described can be used for monitoring fresh and seawater samples for the presence of AIV and to determine
the source of AIV transmission in an outbreak situation. 相似文献
145.
Sara Romani Seyed Reza Mohebbi Seyed Masoud Hosseini Pedram Azimzadeh Mohsen Vahedi Faramarz Derakhshan Mohammad Reza Zali 《Food and environmental virology》2012,4(1):1-5
Noroviruses are one of important agents that cause acute viral gastroenteritis worldwide. These viruses are belonging to Caliciviridae
family and are genetically diverse. To date, there is no valuable data about prevalence of norovirus infection and the dominant
genogroup/genotype among Iranian population. The objective of this study was to determine the frequency of norovirus infection
in Iranian patients with gastroenteritis referred to three hospitals of Tehran and to specify the dominant genogroup/genotype
of this virus among our study population. A total of 293 patients with acute gastroenteritis were included in the study. Detection
of norovirus was performed using RT-PCR method and confirmed by direct sequencing with specific designed primers for capsid
region of norovirus genome. Phylogenetic analysis was performed using the neighbor-joining method. Norovirus strains identified
in our study were subsequently categorized according to previously defined genogroup/genotypes. Of these, norovirus GII was
dominant genogroup. Sixty-five percent (17 of 26) of positive samples were determined as GII and 35% (9 of 26) were determined
as GI, respectively, in 2008–2009. And among 8 sequenced strains of genogroup II the most frequent genotype was GII.3. The
results of this study indicated that norovirus must be considered as one of the infectious causes of acute gastroenteritis
among Iranian population. We also found that GII.3 is more prevalent in our study population. To the best of our knowledge
there is limited data about the role of noroviruses in children and adults’ acute gastroenteritis among Iranian patients and
this prevalence and genotyping report of norovirus infection could be remarkable for further studies. 相似文献
146.
A framework for analyzing climate change adaptations as actions 总被引:1,自引:0,他引:1
Klaus Eisenack Rebecca Stecker 《Mitigation and Adaptation Strategies for Global Change》2012,17(3):243-260
Developing generalized theories about adaptation to climate change requires common concepts to map different adaptation situations.
The paper aims to contribute to this endeavor by presenting a novel framework that conceptualizes adaptations to climate change
as actions. The framework is intended to systematically analyze the actor relations involved in adaptations and the barriers
to their implementation. By combining established scientific action theories with terminology from the Intergovernmental Panel
on Climate Change (IPCC) in an innovative way, it can be used to clarify the notion of adaptation used in adaptation assessments.
The framework’s potential is illustrated by a case study on cooling water management in the river Rhine catchment and by the
elucidation of some prominent concepts in adaptation research. We show that by framing adaptations as actions, the purpose
of adaptations and how they tend to connect up in means-ends-chains becomes crucial. Actors can take different functional
roles as exposure unit, operator and receptor of adaptation. A mismatch of these roles can lead to barriers to adaptation,
of which we deduce four types: complex actor relations, missing operators, missing means and unemployed means. The case study
yields a complex bundle of adaptations, and shows that the potential barriers involved are quite diverse. There is thus no
blueprint solution. Although we identify entry points for adaptation, the analysis leads to a skeptical conclusion for adapting
cooling water management in the whole Rhine catchment. 相似文献
147.
Ellen M. Douglas Paul H. Kirshen Michael Paolisso Chris Watson Jack Wiggin Ashley Enrici Matthias Ruth 《Mitigation and Adaptation Strategies for Global Change》2012,17(5):537-562
We explored the possible future impacts of increased coastal flooding due to sea level rise and the potential adaptation responses
of two urban, environmental justice communities in the metropolitan Boston area of Massachusetts. East Boston is predominantly
a residential area with some industrial and commercial activities, particularly along the coastal fringe. Everett, a city
to the north of Boston, has a diversified industrial and commercial base. While these two communities have similar socioeconomic
characteristics, they differ substantially in the extent to which residents would be impacted by increased coastal flooding.
In East Boston, a large portion of residents would be flooded, while in Everett, it is the commercial/industrial districts
that are primarily vulnerable. Through a series of workshops with residents in each community, we found that the target populations
do not have an adaptation perspective or knowledge of any resources that could assist them in this challenge. Furthermore,
they do not feel included in the planning processes within their communities. However, a common incentive for both communities
was an intense commitment to their communities and an eagerness to learn more and become actively engaged in decisions regarding
climate change adaptation. The lessons that can be applied to other studies include 1) images are powerful tools in communicating
concepts, 2) understanding existing cultural knowledge and values in adaptation planning is essential to the planning process
and 3) engaging local residents at the beginning of the process can create important educational opportunities and develop
trust and consensus that is necessary for moving from concept to implementation. 相似文献
148.
Makino Yamada Yamanoshita Masahiro Amano 《Mitigation and Adaptation Strategies for Global Change》2012,17(4):425-440
It has been recognized that the involvement of local community is essential to ensure the sustainability of A/R CDM (afforestation/reforestation
clean development mechanism) project. This study verifies if the risks of non-permanence and leakage are addressed in a registered
small scale A/R CDM project in Vietnam. Workshops, interviews, and a questionnaire survey of local villagers revealed that
the project has caused a shortage of land for conventional activities such as grazing, fuel wood collection and shifting cultivation,
and consequently posed the risks of project non-permanence and leakage. It is suggested that participation of all stakeholders
in the community to the A/R CDM project beyond existing land tenure and adequate carbon benefit sharing according to the level
of contribution to the project are required to reduce the risk of non permanence. To ensure the participation, the community
should have capability such as consensus building and collective action. Leakage would be minimized if the community has alternative
measures to the conventional activities before starting the project. We argue that it is necessary to first develop a community’s
capabilities in the readiness phase of any A/R CDM project in order to reduce the risks for the project sustainability, and
that new sources of funding are needed for this purpose. 相似文献
149.
Building regional priorities in forests for development and adaptation to climate change in the Congo Basin 总被引:1,自引:0,他引:1
Denis J. Sonwa Johnson N. Nkem Monica E. Idinoba Mekou Y. Bele Cyprain Jum 《Mitigation and Adaptation Strategies for Global Change》2012,17(4):441-450
Indentifying common priorities in shared natural resource systems constitutes an important platform for implementing adaptation
and a major step in sharing a common responsibility in addressing climate change. Predominated by discourses on REDD + (Reduced
Emissions from Deforestation and Forest Degradation and conservation, sustainable management of forests and enhancement of
forest carbon stocks in developing countries) with little emphasis on adaptation there is a risk of lack of policy measures
in addressing climate change in the Congo Basin. Forest products and ecosystem services provide security portfolios for the
predominantly rural communities, and play major roles in national development programmes in both revenue and employment opportunities.
Thus, raising the profile of forests in the policy arena especially in the twin roles of addressing climate change in mitigation
and adaptation and achieving resilient development is crucial. Within the framework of the Congo Basin Forests and Climate
Change Adaptation project (COFCCA) project, science policy dialogue was conducted to identify and prioritize forest based
sectors vulnerable to climate change but important to household livelihoods and national development. The goal of the prioritization
process was for the development of intervention in forest as measures for climate change adaptation in Central Africa. Participants
constituted a wide range of stakeholders (government, Non Governmental Organizations, research institutions, universities,
community leaders, private sectors etc.) as representatives from three countries directly involved in the project: Cameroon,
Central African Republic and Democratic Republic of Congo. Building on national priorities, four forest related sectors were
identified as common priorities at the regional level for focus on climate change adaptation. These sectors included: (1)
energy with emphasis on fuel wood and Charcoal; (2) Water principally quality, quantity, accessibility, etc.; (3) Food with emphasis on Non Timber Forest Products, and (4) Health linked to healthcare products (medicinal plants). Using these prioritized sectors, the project focused on addressing the impacts of climate change on local communities and the development of adaptation strategies in the three pilot countries
of the Congo Basin region. The four sectors constitute the key for development in the region and equally considered as priority sectors in the poverty
reduction papers. Focused research on these sectors can help to inject the role of forests in national and local development
and their potentials contributions to climate change adaptation in national and public discourses. Mainstreaming forest for
climate change adaptation into national development planning is the key to improve policy coherence and effectiveness in forest
management in the region. 相似文献
150.
B.R. Rawal Rahul Ribeiro Rajesh Malhotra Naresh Bhatnagar 《Journal of Manufacturing Processes》2012,14(3):216-223
Several researchers have stressed the need for a proper implant-patient match in hip joint replacements, in particular, for cementless femoral stems. Some of the complications of mismatch are aseptic loosening, improper load distribution, and discomfort. In this study, the differences in dimensions between femurs of elderly Indians and those of populations from other regions are compared in order to solve the problem of a possible geometric mismatch between a selected implant and the femurs of an Indian patients are concerned. This paper also describes a methodology for implant designing from measured anthropometric data, fit evaluation, finite element (FE) stress analysis and subsequently implant manufacturing using the CAM (Computer Aided Manufacturing) technique. The machining of the Titanium alloy femoral stem is usually performed on a 5 Axis CNC (Computer Numerical Control) machining center. However, in this study the machining of the femoral stem was effectively performed on a 3 Axis CNC machining center to emphasize on economical benefits for low cost manufacturing strategy. 相似文献