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1.
A number of checks can be done to assess reliability of attitudinal data pertaining to fertility. We ascertain how births that would be considered unintended, based on Time 1 reports of fertility intentions, are classified by respondents at a second interview after the birth occurred. The 1988 National Survey of Family Growth and a telephone reinterview allow us to identify respondents who initially intended to postpone or stop childbearing, but who then had a birth, and to analyze the reports they gave of the wantedness of the pregnancy leading to the birth. We also examine wantedness responses of women who claimed in 1988 that they intended to conceive within the next few years. Reports are compared across a range of respondent characteristics and circumstances, including changes in marital status since the initial interview. The analysis reveals nontrivial inconsistency between women's stated birth intentions and their reports about the wantedness of subsequent births. Details across subgroups are examined. Results also provide new information about effects of duration since birth on intention reports. 相似文献
2.
This article concentrates on the care for people who suffer from progressive dementia. Dementia has a great impact on a person’s well‐being as well as on his or her social environment. Dealing with dementia raises moral issues and challenges for participants, especially for family members. One of the moral issues in the care for people with dementia is centred on responsibilities; how do people conceive and determine their responsibilities towards one another? To investigate this issue we use the theoretical perspective of Margaret Walker. She states that ideas about identity play a crucial role in patterns of normative expectations with regard to the distribution of responsibilities in daily practices of care. The results of this study show how the identity of a family‐member is put under pressure and changes during her loved one’s illness that leads to difficulties and misunderstandings concerning the issue of responsibility. These results offer an insight into the complexities of actual practices of responsibility and highlight the importance for those caring for people with dementia of attending carefully to how they see themselves and how they see other people involved (Who am I? Who do I want to be for the other?). Answers to such questions show what people expect from themselves and from one another, and how they, at any rate, are distributing responsibilities in a given situation. Professional caregivers should take into account that family members might have different ideas about who they are and consequently about what their responsibilities are. 相似文献
3.
Improved nitrogen removal by application of new nitrogen-cycle bacteria 总被引:14,自引:0,他引:14
Jetten Mike S.M. Schmid Markus Schmidt Ingo Wubben Mariska van Dongen Udo Abma Wiebe Sliekers Olav Revsbech Niels Peter Beaumont Hubertus J.E. Ottosen Lars Volcke Eveline Laanbroek H.J. Campos-Gomez Jose Luis Cole Jeff van Loosdrecht Mark Mulder Jan Willem Fuerst John Richardson David van de Pas Katinka Mendez-Pampin Ramon Third Katie Cirpus Irina van Spanning Rob Bollmann Annette Nielsen Lars Peter den Camp Huub Op Schultz Carl Gundersen Jens Vanrolleghem Peter Strous Marc Wagner Michael Kuenen J. Gijs 《Reviews in Environmental Science and Biotechnology》2002,1(1):51-63
In order to meet increasingly stringentEuropean discharge standards, new applicationsand control strategies for the sustainableremoval of ammonia from wastewater have to beimplemented. In this paper we discuss anitrogen removal system based on the processesof partial nitrification and anoxic ammoniaoxidation (anammox). The anammox process offersgreat opportunities to remove ammonia in fullyautotrophic systems with biomass retention. Noorganic carbon is needed in such nitrogenremoval system, since ammonia is used aselectron donor for nitrite reduction. Thenitrite can be produced from ammonia inoxygen-limited biofilm systems or in continuousprocesses without biomass retention. Forsuccessful implementation of the combinedprocesses, accurate biosensors for measuringammonia and nitrite concentrations, insight inthe complex microbial communities involved, andnew control strategies have to be developed andevaluated. 相似文献
4.
Fieke S Koopman Anita Beelen Karin H Gerrits Gijs Bleijenberg Tineke A Abma Marianne de Visser Frans Nollet 《BMC neurology》2010,10(1):8
Background
Postpoliomyelitis Syndrome (PPS) is a complex of late onset neuromuscular symptoms with new or increased muscle weakness and muscle fatigability as key symptoms. Main clinical complaints are severe fatigue, deterioration in functional abilities and health related quality of life. Rehabilitation management is the mainstay of treatment. Two different therapeutic interventions may be prescribed (1) exercise therapy or (2) cognitive behavioural therapy (CBT). However, the evidence on the effectiveness of both interventions is limited. The primary aim of the FACTS-2-PPS trial is to study the efficacy of exercise therapy and CBT for reducing fatigue and improving activities and quality of life in patients with PPS. Additionally, the working mechanisms, patients' and therapists' expectations of and experiences with both interventions and cost-effectiveness will be evaluated. 相似文献5.
Jetten MS Sliekers O Kuypers M Dalsgaard T van Niftrik L Cirpus I van de Pas-Schoonen K Lavik G Thamdrup B Le Paslier D Op den Camp HJ Hulth S Nielsen LP Abma W Third K Engström P Kuenen JG Jørgensen BB Canfield DE Sinninghe Damsté JS Revsbech NP Fuerst J Weissenbach J Wagner M Schmidt I Schmid M Strous M 《Applied microbiology and biotechnology》2003,63(2):107-114
Recently, two fresh water species, "Candidatus Brocadia anammoxidans" and "Candidatus Kuenenia stuttgartiensis", and one marine species, "Candidatus Scalindua sorokinii", of planctomycete anammox bacteria have been identified. "Candidatus Scalindua sorokinii" was discovered in the Black Sea, and contributed substantially to the loss of fixed nitrogen. All three species contain a unique organelle—the anammoxosome—in their cytoplasm. The anammoxosome contains the hydrazine/hydroxylamine oxidoreductase enzyme, and is thus the site of anammox catabolism. The anammoxosome is surrounded by a very dense membrane composed almost exclusively of linearly concatenated cyclobutane-containing lipids. These so-called 'ladderanes' are connected to the glycerol moiety via both ester and ether bonds. In natural and man-made ecosystems, anammox bacteria can cooperate with aerobic ammonium-oxidising bacteria, which protect them from harmful oxygen, and provide the necessary nitrite. The cooperation of these two groups of ammonium-oxidising bacteria is the microbial basis for a sustainable one reactor system, CANON (completely autotrophic nitrogen-removal over nitrite) to remove ammonia from high strength wastewater. 相似文献
6.
van Ginkel CG Middelhuis BJ Spijk F Abma WR 《Journal of industrial microbiology & biotechnology》2005,32(1):1-6
The discharge of bromate, a suspected carcinogen, will be restricted in the near future. To assess the possibility of biotechnological treatment of bromate-containing wastewaters, the removal of bromate by chlorate-reducing microorganisms was studied. The removal of bromate and chlorate was studied in laboratory gas-lift bioreactors supplied with hydrogen gas as electron donor in the absence of molecular oxygen. In these reactors, bromate was reduced cometabolically by chlorate-respiring microorganisms. To allow the cometabolic reduction of bromate, a chlorate:bromate molar ratio of at least 3:1 was required. The cometabolic conversion permitted almost complete reduction of bromate into bromide at hydraulic retention times of at least 6 h. Optimal bromate reduction activity was observed at approximately 35°C. The pH optimum was between 7 and 8. Bromate reduction in excess of 80% and a maximum bromate reduction rate of 2.3 g l–1 day–1 in a pilot-scale gas-lift bioreactor demonstrates that the process is sustainable. 相似文献
7.
CANON and Anammox in a gas-lift reactor 总被引:57,自引:0,他引:57
Anoxic ammonium oxidation (Anammox) and Completely Autotrophic Nitrogen removal Over Nitrite (CANON) are new and promising microbial processes to remove ammonia from wastewaters characterized by a low content of organic materials. These two processes were investigated on their feasibility and performance in a gas-lift reactor. The Anammox as well as the CANON process could be maintained easily in a gas-lift reactor, and very high N-conversion rates were achieved. An N-removal rate of 8.9 kg N (m(3) reactor)(-1) day(-1) was achieved for the Anammox process in a gas-lift reactor. N-removal rates of up to 1.5 kg N (m(3) reactor)(-1) day(-1) were achieved when the CANON process was operated. This removal rate was 20 times higher compared to the removal rates achieved in the laboratory previously. Fluorescence in situ hybridization showed that the biomass consisted of bacteria reacting to NEU, a 16S rRNA targeted probe specific for halotolerant and halophilic Nitrosomonads, and of bacteria reacting to Amx820, specific for planctomycetes capable of Anammox. 相似文献
8.
Application, eco-physiology and biodiversity of anaerobic ammonium-oxidizing bacteria 总被引:1,自引:0,他引:1
Boran Kartal Laura van Niftrik Olav Sliekers Markus C. Schmid Ingo Schmidt Katinka van de Pas-Schoonen Irina Cirpus Wouter van der Star Mark van Loosdrecht Wiebe Abma J. Gijs Kuenen Jan-Willem Mulder Mike S. M. Jetten Huub Op den Camp Marc Strous Jack van de Vossenberg 《Reviews in Environmental Science and Biotechnology》2004,3(3):255-264
The demand for new and sustainable systems for nitrogen removal has increased dramatically in the last decade. It is clear that the conventional systems cannot deal with the increasing nitrogen loads in a cost effective way. As an alternative, the implementation of the anammox (anaerobic ammonium oxidation) process in the treatment of wastewater with high ammonium concentrations has been started. The compact anammox reactors can sustain high nitrogen loads without any problems. The highest observed anammox capacity is 8.9 kg N removed m-3 reactor day-1. The first 75 m3 anammox reactor is operating in Rotterdam, the Netherlands, combined with the partial nitrification process Single reaction system for High Ammonium Removal Over Nitrite (SHARON). Partial nitrification and anammox can also be combined in one reactor systems like Completely Autotrophic Nitrogen removal Over Nitrite (CANON) or Oxygen Limited Ammonium removal via Nitrification Denitrification (OLAND) where aerobic ammonium-oxidizing bacteria (AOB) and anammox bacteria cooperate under oxygen-limitation. These systems remove about 1.5 kg N m-3 reactor day-1. In addition to ammonium, urea can also be converted in the CANON system after a two-week adaptation period. The ecophysiological properties of the anammox bacteria make them very well suited to convert ammonium and nitrite. The Ks values for ammonium and nitrite are below 5 M. However, nitrite above 10 mM is detrimental for the anammox process, and oxygen reversibly inhibits the process at concentrations as low as 1 M. Acetate and propionate can be used by the anammox bacteria to convert nitrite and nitrate, whereas methanol and ethanol severely inhibit the anammox reaction. The enzyme hydroxylamine/hydrazine oxidoreductase (HAO), one of the key enzymes, is located in the anammoxosome, which is a membrane bound organelle. The membranes of the anammox bacteria contain unique ladderane lipids and hopanoids. The bacteria responsible for the anammox reaction are related to the Planctomycetes. The first anammox bacteria were isolated via Percoll centrifugation and characterized as Candidatus Brocadia anammoxidans. Survey of different wastewater treatment plants using anammox specific 16S rRNA gene primers and anammox specific oligonucleotide probes has revealed the presence of at least three other anammox bacteria, which have been tentatively named Candidatus Kuenenia stuttgartiensis, Candidatus Scalindua wagneri and Candidatus Scalindua brodae. A close relative of the latter, Candidatus Scalindua sorokinii was found to be responsible for about 50% of the nitrogen conversion in the anoxic zone of the Black Sea, making the anammox bacteria an important player in the oceanic nitrogen cycle. 相似文献
9.
Characterization of Microbial Communities Removing Nitrogen Oxides from Flue Gas: the BioDeNOx Process 总被引:3,自引:0,他引:3 下载免费PDF全文
Rajkumari Kumaraswamy Udo van Dongen J. Gijs Kuenen Wiebe Abma Mark C. M. van Loosdrecht Gerard Muyzer 《Applied microbiology》2005,71(10):6345-6352
BioDeNOx is an integrated physicochemical and biological process for the removal of nitrogen oxides (NOx) from flue gases. In this process, the flue gas is purged through a scrubber containing a solution of Fe(II)EDTA2−, which binds the NOx to form an Fe(II)EDTA·NO2− complex. Subsequently, this complex is reduced in the bioreactor to dinitrogen by microbial denitrification. Fe(II)EDTA2−, which is oxidized to Fe(III)EDTA− by oxygen in the flue gas, is regenerated by microbial iron reduction. In this study, the microbial communities of both lab- and pilot-scale reactors were studied using culture-dependent and -independent approaches. A pure bacterial strain, KT-1, closely affiliated by 16S rRNA analysis to the gram-positive denitrifying bacterium Bacillus azotoformans, was obtained. DNA-DNA homology of the isolate with the type strain was 89%, indicating that strain KT-1 belongs to the species B. azotoformans. Strain KT-1 reduces Fe(II)EDTA·NO2− complex to N2 using ethanol, acetate, and Fe(II)EDTA2− as electron donors. It does not reduce Fe(III)EDTA−. Denaturing gradient gel electrophoresis analysis of PCR-amplified 16S rRNA gene fragments showed the presence of bacteria closely affiliated with members of the phylum Deferribacteres, an Fe(III)-reducing group of bacteria. Fluorescent in situ hybridization with oligonucleotide probes designed for strain KT-1 and members of the phylum Deferribacteres showed that the latter were more dominant in both reactors. 相似文献
10.
In this analysis we have compared two attitudinal reports, from interviews two years apart, of the same event for consistency over time. We have looked at women's self-reports, and at their proxy reports for partners' attitudes as well. The inconsistent reports of women's own views tended to shift slightly toward more favorable reports at the second interview (15 percent more positive versus 10 percent more negative). More specifically, 7.5 percent of women who reported at Time 1 that their most recent births had been unwanted switched to more favorable reports at Time 2, and about the same percentage of women who reported Table 4, the findings would suggest that some of the groups typically considered to be most "at risk" were those who were also most apt to report inconsistently. This findings should signal some concern in the policy community. Net of other factors, there is no effect of income, but a number of at-risk groups remained significantly more likely than others to change their reports over time. Of particular concern is the finding that women who reported their pregnancies as mistimed or unwanted were so much more likely to change their reports over time than were women who initially said that their pregnancies had been well timed. When we look at the direction of change, it is clear that, with some exceptions, the more "at risk" groups were more likely to shift in a more negative direction, while the less "at risk" groups were less likely to do so; and at times they were more likely to report more favorably at the second interview. Although somewhat hampered by small sample sizes in the analysis of Time 1 mistimed and unwanted reports, results confirmed that certain subgroups were not only more apt to report inconsistently, they were also more likely to do so in specific directions. To the extent that future survey questions can emphasize to respondents that they should focus on the time of conception, and not on current status, inconsistency across groups may be reduced. 相似文献