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41.
We developed quantitative PCR (qPCR) assays to distinguish each of the four clades (A–D) of dinoflagellate endosymbionts (genus Symbiodinium) commonly found in Caribbean corals. We applied these primer sets, which target portions of the multi-copy ribosomal DNA (rDNA) gene family, to assess the presence/absence of symbionts in clade D (as indicated by the detection of clade D DNA). We detected these symbionts in five of six Caribbean host species/genera (21% of samples analyzed, N = 10 of 47 colonies), from which clade D had rarely or never been observed. This suggests that Symbiodinium in clade D are present in a higher diversity of coral species than previously thought. This qPCR-based approach can improve our understanding of the total microbial diversity associated with corals, particularly in hosts thought to be relatively specific, and has many other potential applications for studies of coral reef ecology and conservation. 相似文献
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de Aragão Umbuzeiro G Freeman HS Warren SH de Oliveira DP Terao Y Watanabe T Claxton LD 《Chemosphere》2005,60(1):55-64
To verify whether dyes emitted within the discharge of a dye processing plant were contributing to the mutagenicity repeatedly found in the Cristais River, Sao Paulo, Brazil, we chemically characterized the following mutagenic samples: the treated industrial effluent, raw and treated water, and the sludge produced by a Drinking Water Treatment Plant (DWTP) located approximately 6 km from the industrial discharge. Considering that 20% of the dyes used for coloring activities might be lost to wastewaters and knowing that several dyes have mutagenic activity, we decided to analyze the samples for the presence of dyes. Thin layer chromatographic analysis indicated the presence of three prevalent dyes in all samples, except for the drinking water. This combination of dyes corresponded to a commercial product used by the industry, and it tested positive in the Salmonella assay. The structures of the dye components were determined using proton magnetic resonance and mass spectrometric (MS) methods, and the dyes were tested for mutagenicity. The blue component was identified as the C.I. Disperse Blue 373, the violet as C.I. Disperse Violet 93, and the orange as C.I. Disperse Orange 37. The dyes showed mutagenic responses of 6300, 4600, and 280 revertants/microg for YG1041 with S9 respectively. A bioassay-directed fractionation/chemical analysis showed that the C.I. Disperse Blue 373 contributed 55% of the mutagenic activity of the DWTP sludge. We showed that these dyes contributed to the mutagenic activity found in the Cristais River environmental samples analyzed and are indirectly affecting the quality of the related drinking water. Therefore, we believe that this type of discharge should be more thoroughly characterized chemically and toxicologically. Additionally, human and ecological risks associated with the release of dye processing plant effluents should be more fully investigated, especially where the resultant water is taken for human consumption. 相似文献
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Community motivations to engage in conservation behavior to conserve the Sumatran orangutan 下载免费PDF全文
Danielle Nilsson Galina Gramotnev Greg Baxter James R.A. Butler Serge A. Wich Clive A. McAlpine 《Conservation biology》2016,30(4):816-826
Community‐based conservation programs in developing countries are often based on the assumption that heteronomous motivation (e.g., extrinsic incentives such as economic rewards and pressure or coercion to act) will incite local communities to adopt conservation behaviors. However, this may not be as effective or sustainable as autonomous motivations (e.g., an intrinsic desire to act due to inherent enjoyment or self‐identification with a behavior and through freedom of choice). We analyzed the comparative effectiveness of heteronomous versus autonomous approaches to community‐based conservation programs through a case study of Sumatran orangutan (Pongo abelii) conservation in 3 villages in Indonesia. Each village had a different conservation program design. We surveyed people (n = 240) to determine their motivations for and behavior changes relative to orangutan and orangutan habitat (forest) protection. Heteronomous motivations (e.g., income from tourism) led to greater self‐reporting of behavior change toward orangutan protection. However, they did not change self‐reported behavior toward forest (i.e., orangutan habitat) protection. The most effective approach to creating self‐reported behavior change throughout the community was a combination of autonomous and heteronomous motivations. Individuals who were heteronomously motivated to protect the orangutan were more likely to have changed attitudes than to have changed their self‐reported behavior. These findings demonstrate that the current paradigm of motivating communities in developing countries to adopt conservation behaviors primarily through monetary incentives and rewards should consider integrating autonomous motivational techniques that promote the intrinsic values of conservation. Such a combination has a greater potential to achieve sustainable and cost‐effective conservation outcomes. Our results highlight the importance of using in‐depth sociopsychological analyses to inform the design and implementation of community‐based conservation programs. 相似文献
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Sather ME Mathew J Nguyen N Lay J Golod G Vet R Cotie J Hertel T Aaboe E Callison R Adam J Keese D Freise J Hathcoat A Sakizzie B King M Lee C Oliva S San Miguel G Crow L Geasland F 《Journal of environmental monitoring : JEM》2008,10(11):1319-1325
Ambient ammonia monitoring using Ogawa passive samplers was conducted in the Four Corners area and eastern Oklahoma, USA during 2007. The resulting data will be useful in the multipollutant management of ozone, nitrogen oxides, and visibility (atmospheric regional haze) in the Four Corners area, an area with growing oil/gas production and increasing coal-based power plant construction. The passive monitoring data also add new ambient ammonia concentration information for the U.S. and will be useful to scientists involved in present and future visibility modeling exercises. Three week integrated passive ammonia samples were taken at five sites in the Four Corners area and two sites in eastern Oklahoma from December, 2006 through December, 2007 (January, 2008 for two sites). Results show significantly higher regional background ammonia concentrations in eastern Oklahoma (1.8 parts per billion (ppb) arithmetic mean) compared to the Four Corners area (0.2 ppb arithmetic mean). Annual mean ammonia concentrations for all Four Corners area sites for the 2007 study ranged from 0.2 ppb to 1.5 ppb. Peak ambient ammonia concentrations occurred in the spring and summer in both areas. The passive samplers deployed at the Stilwell, Oklahoma site compared favorably with other passive samplers and a continuous ammonia monitoring instrument. 相似文献
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Christopher Thellen Megan Coyne Danielle Froio Margaret Auerbach Carl Wirsen Jo Ann Ratto 《Journal of Polymers and the Environment》2008,16(1):1-11
A series of polyhydroxyalkanoates (PHA), all containing 1% nucleating agent but varying in structure, were melt-processed
into films through single screw extrusion techniques. This series consisted of three polyhydroxybutyrate (PHB) and three polyhydroxybutyrate-valerate
(PHBV) resins with varying valerate content. Processing parameters of temperature in the barrel (165–173 °C) and chill rolls
(60 °C) were optimized to obtain cast films. The gel-permeation chromatography (GPC) results showed a loss of 8–19% of the
polymer’s initial molecular weight due to extrusion processing. Modulated differential scanning calorimetry (MDSC) displayed
glass transition temperatures of the films ranging from −4.6 to 6.7 °C depending on the amount of crystallinity in the film.
DSC data were also used to calculate the percent crystallinity of each sample and slightly higher crystallinity was observed
in the PHBV series of samples. X-ray diffraction patterns did not vary significantly for any of the samples and crystallinity
was confirmed with X-ray data. Dynamic mechanical analysis (DMA) verified the glass transition trends for the films from DSC
while loss modulus (E′) reported at 20 °C showed that the PHBV (3,950–3,600 MPa) had the higher E′ values than the PHB (3,500–2,698 MPa) samples. The Young’s modulus values of the PHB and PHBV samples ranged from 700 to
900 MPa and 900 to 1,500 MPa, respectively. Polarized light microscopy images revealed gel particles in the films processed
through single-screw extrusion, which may have caused diminished Young’s modulus and tensile strength of these films. The
PHBV film samples exhibited the greatest barrier properties to oxygen and water vapor when compared to the PHB film samples.
The average oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) for the PHBV samples was 247 (cc-mil/m2-day) and 118 (g-mil/m2-day), respectively; while the average OTR and WVTR for the PHB samples was 350 (cc-mil/m2-day) and 178 (g-mil/m2-day), respectively. Biodegradation data of the films in the marine environment demonstrated that all PHA film samples achieved
a minimum of 70% mineralization in 40 days when run in accordance with ASTM 6691. For static and dynamic incubation experiments
in seawater, microbial action resulting in weight loss as a function of time showed all samples to be highly biodegradable
and correlated with the ASTM 6691 biodegradation data. 相似文献
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