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Abstract The Open Bay Island skink (Oligosoma taumakae) is one of New Zealand's rarest lizard species. Until 2010, it was known only from two small islands in the Open Bay Island Group, a Māori-owned wildlife sanctuary in South Westland, New Zealand. Skinks on these islands are threatened by predation from weka (Gallirallus australis), a flightless native rail thought to have been introduced to the Open Bay Islands c. 100 years ago. Here, we describe the discovery of Open Bay Island skinks on two vegetated rock stacks located off the coast of Barn Bay, 52 km southwest of the Open Bay Islands. Although small (c. 0.10 and 0.36 ha), the Barn Islands appear to be predator-free, providing an important sanctuary for the skinks. We recommend: (1) a survey of mainland sites with suitable habitat; and (2) an evaluation of the need for island biosecurity measures for detecting and responding to incursions of small mammals. 相似文献
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Thomas M. Burton Donald G. Uzarski Robert S. Stelzer Susan L. Eggert William V. Sobczak Dennis M. Mullen 《Hydrobiologia》2000,439(1-3):61-76
Potential effects of extremely low frequency (ELF) electromagnetic fields on periphyton were studied from 1983 to 1993 using a Before, After, Control and Impact design. The study was conducted at two sites on the Ford River, a fourth-order brown water trout stream in Dickinson County, Michigan. The Reference site received 4.9–6.5 times less exposure to ground electric fields and from 300 to 334 times less exposure to magnetic flux from 1989 to 1993 when the antenna was operational at 76 Hz than did the Antenna site. The objective of the study was to determine if ELF electromagnetic fields had caused changes in structure and/or function of algal communities in the Ford River. Significant differences in chlorophyll a standing crop and daily accumulation rate (a surrogate for primary productivity), and organic matter standing crop and daily accumulation rate were observed between the Reference and Antenna site after the antenna became operational. These four related community function variables all increased at the Antenna site with largest and most consistent increases occurring for chlorophyll measures. Compared to pre-operational data, the increase in chlorophyll at the Antenna site also occurred during a period of low amperage testing in 1986–1988, and did not increase further when the antenna became fully operational in 1989, indicating a low threshold for response. There was no significant differences between the Antenna and Reference sites in community structure variables such as diversity, evenness and the relative abundance of dominant diatoms. Thus, 76 Hz ELF electromagnetic radiation apparently did not change the basic makeup of the diatom community but did increase accumulation rates and standing crops of chlorophyll a and organic matter. 相似文献
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Both the Entamoeba histolytica lectin, a virulence factor for the causative
agent of amebiasis, and the mammalian hepatic lectin bind to
N-acetylgalactosamine (GalNAc) and galactose (Gal) nonreducing termini on
oligosaccharides, with preference for GalNAc. Polyvalent GalNAc-
derivatized neoglycoproteins have >1000-fold enhanced binding affinity
for both lectins (Adler,P., Wood,S.J., Lee,Y.C., Lee,R.T., Petri,W.A.,Jr.
and Schnaar,R.L.,1995, J. Biol. Chem ., 270, 5164-5171). Substructural
specificity studies revealed that the 3-OH and 4-OH groups of GalNAc were
required for binding to both lectins, whereas only the E.histolytica lectin
required the 6-OH group. Whereas GalNAc binds with 4-fold lower affinity to
the E.histolytica lectin than to the mammalian hepatic lectin,
galactosamine and N-benzoyl galactosamine bind with higher affinity to the
E. histolytica lectin. Therefore, a synthetic scheme for converting
polyamine carriers to poly-N-acyl galactosamine derivatives (linked through
the galactosamine primary amino group) was developed to test whether such
ligands would bind the E.histolytica lectin with high specificity and high
affinity. Contrary to expectations, polyvalent derivatives including
GalN6lys5, GalN4desmosine, GalN4StarburstTMdendrimer, and
GalN8StarburstTMdendrimer demonstrated highly enhanced binding to the
mammalian hepatic lectin but little or no enhancement of binding to the
E.histolytica lectin. We propose that the mammalian hepatic lectin binds
with greatest affinity to GalNAc "miniclusters," which mimic branched
termini of N-linked oligosaccharides, whereas the E.histolytica lectin
binds most effectively to "maxiclusters," which may mimic more widely
spaced GalNAc residues on intestinal mucins.
相似文献
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Marker assisted selection using best linear unbiased prediction 总被引:1,自引:0,他引:1
49.
Ocaña-de Jesús RL AT Gutiérrez-Ibáñez JR Sánchez-Pale MD Mariezcurrena-Berasain G Velázquez-Garduño A Laguna Cerda I Rojas Puebla 《Phyton》2015,84(1):45-50
The aim of the current research was to determine tomato (Solanum lycopersicum L.) microbiological quality produced under greenhouse conditions in 5 municipalities of the State of Mexico. Studies were conducted during the 2013 production cycle to know the risks and apply prevention strategies prior to its consumption. A microbiological analysis of samples of irrigation water, soil and 100 tomato fruits variety cid was performed to determine Aerobic Mesophiles, Total Coliforms and Fecal Coliforms. The methodology used were those according to the Official Mexican Standards NOM- 109-SSA1-1994, NOM-110-SSA1-1994, NOM-092-SSA1-1994, NOM-113-SSA1-1994, and the Regulations of the National French Organization for Standardization (AFNOR) NF V08-60, and NOM-093-SSA1-1994, which establish the allowable limits for the study microorganisms. The results showed a zero level of pollution in water and soil samples. For fruits, levels of Aerobic Mesophilic were within the maximum limits permitted by the standards. The municipality of Texcaltitlan showed the highest average for these microorganisms (10083.80 CFU/mL). Huixquilucan showed 2266.84 CFU/mL for Total Coliforms. For Fecal Coliforms, municipalities of Coatepec and Texcaltitlan exceeded the allowed limit. 相似文献
50.
We designed an open-ended community metabolism chamber to simultaneously measure surface and hyporheic metabolism. Our chamber design eliminated reaeration, compartmentalized metabolism, maintained ambient conditions and included hyporheic respiration. We compared results from our hyporheic chamber to results obtained from: (1) closed benthic community metabolism chambers constructed as recommended by Bott et al. (1978), and (2) whole-stream metabolism techniques as modified by Marzolf et al. (1994). Simultaneous comparisons of all three procedures were made for a 35 m riffle section of Augusta Creek, a 3rd-order Michigan stream, in July 1997 and repeated in July 1998. Simultaneous comparisons of all three procedures were also made for a 30 m sandy run section of Augusta Creek in September 1997, and repeated in September 1998. Our hyporheic chamber estimates for community respiration (CR24) were similar to those obtained using the whole-stream metabolism procedure but were considerably higher than estimates obtained using the closed benthic chambers in three of the four experiments. These data suggest that our chamber design provided estimates of community metabolism which included both benthic and hyporheic respiration. The chamber incorporates several positive aspects of both closed chambers and the whole-stream method. This new method can be replicated, eliminates the need for a reaeration coefficient, ambient conditions are better approximated since it remains an open system, and it appears to provide more realistic estimates of whole-stream metabolism compared to the traditional chamber approach. 相似文献