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1.
Maria João Feio Trefor B. Reynoldson Verónica Ferreira Manuel Augusto S. Graça 《Hydrobiologia》2007,579(1):55-68
We sampled macroinvertebrates at 75 locations in the Mondego river catchment, Central Portugal, and developed a predictive
model for water quality assessment of this basin, based on the Reference Condition Approach. Sampling was done from June to
September 2001. Fifty-five sites were identified as “Reference sites” and 20 sites were used as “Test sites” to test the model.
At each site we also measured 40 habitat variables to characterize water physics and chemistry, habitat type, land use, stream
hydrology and geographic location. Macroinvertebrates were generally identified to species or genus level; a total of 207
taxa were found. By Unweighted Pair Group Method with Arithmetic mean (UPGMA) clustering and analysis of species contribution
to similarities percentage (SIMPER), two groups of reference sites were established. Using Discriminant Analysis (stepwise
forward), four variables correctly predicted 78% of the reference sites to the appropriate group: stream order, pool quality,
substrate quality and current velocity. Test sites’ environmental quality was established from their relative distance to
reference sites, in MDS ordination space, using a series of bands (BEAST methodology). The model performed well at upstream
sites, but at downstream sites it was compromised by the lack of reference sites. As with the English RIVPACS predictive model,
the Mondego model should be continually improved with the addition of new reference sites. The adaptation of the Mondego model
methodology to the Water Framework Directive is possible and would consist mainly of the integration of the WFD typology and
increasing the number of ellipses that define quality bands.
Handling editor: K. Martens 相似文献
2.
J R Lakowicz J Ku?ba W Wiczk I Gryczynski H Szmacinski M L Johnson 《Biophysical chemistry》1991,39(1):79-84
We report the first resolution of both the conformational distribution and end-to-end diffusion coefficient of a flexible molecule. This molecular information was recovered using only the donor intensity decay in a single solvent at a single viscosity, as observed by the technique of frequency-domain fluorometry. This technique can be extended to measurements of structural fluctuations of biological macromolecules. 相似文献
3.
Reiko Yu-Ito Kazuko Ôba Ikuzo Uritani 《Bioscience, biotechnology, and biochemistry》2013,77(8):2087-2091
In addition to HMG-CoA reductase, another HMG-CoA utilizing enzyme is present in the Mt fraction of sweet potato root tissue and its activity interferes with the assay to HMG-CoA reductase activity. 相似文献
4.
Jacek Kęsy Beata Maciejewska Magdalena Sowa Magdalena Szumilak Krzysztof Kawałowski Maja Borzuchowska Jan Kopcewicz 《Plant Growth Regulation》2008,55(1):43-50
It has been shown that both IAA and ethylene application inhibit flower induction in the short-day plant Pharbitis nil. However application of IAA has elevated ethylene production in this plant, as well. Strong enhancement of ethylene production
is also correlated with the night-break effect, which completely inhibits flowering. In order to determine what the role of
IAA and ethylene is in the photoperiodic flower induction in Pharbitis nil, we measured changes in their levels during inductive and non-inductive photoperiods, and the effects of ethylene biosynthesis
and action inhibitors on inhibition of flowering by IAA. Our results have shown that the inhibitory effect of IAA on Pharbitis nil flowering is not physiological but is connected with its effect on ethylene biosynthesis. 相似文献
5.
Inhibition of electroshock-induced seizures by cholecystokinin-related peptides in mice 总被引:1,自引:0,他引:1
The effects of several doses of cholecystokinin octapeptide sulphate ester (CCK-8-SE) and nonsulphated cholecystokinin octapeptide (CCK-8-NS), and two CCK-related peptide analogues Ac-Thr5-caerulein, and nonsulphated Ac-Thr5-caerulein were investigated on electroshock-(ES)-induced seizures after intraperitoneal administration in mice. As parameters, the duration of the tonic and clonic phase of the fit, and those of postictal coma and behavioural depression were measured. CCK-8-SE decreased the duration of the clonic phase; its highest dose, 3.2 mumol/kg, shortened the coma. CCK-8-NS antagonized only slightly the clonic phase of seizure. Ac-Thr5-caerulein did not influence ES-induced seizures in any dose, only increased the duration of behavioural depression. Similarly to CCK-8-NS, the nonsulphated form of Ac-Thr5-caerulein inhibited selectively the clonic phase of seizures. The reference drugs, diazepam and phenobarbital, antagonized dose-dependently and most effectively the tonic phase of ES-induced seizures, but in much higher doses than did the CCK-related peptides. Besides, diazepam increased and phenobarbital decreased the duration of postictal coma. The results showed that the tested CCK-related peptides inhibit prevalently the clonic phase of ES-induced seizures after peripheral administration. 相似文献
6.
Determination was made of the proportion of selected by-products (acetaldehyde, ethyl acetate, methanol, propanol, isobutanol, 2-methyl-butanol, 3-methyl-butanol) of batch and continuous ethanol fermentation carried out with the use of yeastSaccharomyces cerevisiae, strain 0–11, cells immobilized by adsorption on selected carriers (foamed polystyrene, bone shot, beech wood chips, porous glass) as well as by entrapping in calcium alginate and calcium pectinate gel. 相似文献
7.
G. Egea J. M. Ureña X. Graña J. Marsal J. Carreras F. Climent 《Histochemistry and cell biology》1992,97(3):269-275
Summary We have previously reported (Ureña et al. Eur. J. Cell Biol. 1990) that in skeletal muscle, type MM phosphoglycerate mutase isozyme is present in the nucleus as well as in the cytosol. To determine whether type BB phosphoglycerate mutase isozyme is also present in nucleus, the subcellular location of this isozyme was studied in different rat tissues by cell fractionation and immunogold techniques. With the aid of high affinity-purified anti-phosphoglycerate mutase BB isozyme antibodies, the isozyme was located in the nucleus of neuronal, astroglial and liver cells but not in the nucleus of oligodendroglial and endothelial cells. Biochemical studies on purified nuclear fractions also demonstrated the presence of phosphoglycerate mutase activity in the nucleus. Both immunocytochemical and biochemical techniques showed that nuclear phosphoglycerate mutase-specific activity depended on the type of cell.Abbreviations PGAM
phosphoglycerate mutase
- PGAM-M(M)
muscle specific subunit (isozyme) of PGAM
- PGAM-B(B)
brain type subunit (isozyme) of PGAM
- ssDNA
single stranded DNA
- PBS
0.001 M phosphate buffer, pH 7.4, containing 0.15 M NaCl
- kDa
kilodalton 相似文献
8.
Metabolites ofAlternaria alternata were produced on rice as a solid substrate, chosen out of 6 substrates as the most useful. Optimal methods of extraction, purification, and separation of 5 metabolites were elaborated, using liquid — liquid partition, column chromatography, and preparative TLC. Alternariol, alternariol methyl ether, and copper salt of tenuazonic acid were obtained as crystals, altertoxin and altenuene as a film. 相似文献
9.
ba Kazuko; Kondo Katsuyoshi; Doke Noriyuki; Uritani Ikuzo 《Plant & cell physiology》1985,26(5):873-880
Intact tubers of potato (Solanum tuberosum L. cv. Irish Cobblerand an interspecific hybrid between S. tuberosum and S. demissumcv. Rishiri) contain a very low activity of 3-hydroxy-3-methylglutaryl(HMG)-CoA reductase. The activity increased first in responseto slicing, and again in response to additional treatments suchas inoculation with an incompatible race of Phytophthora infestans,application of a hyphal wall component of the fungus or HgCl2solution, and then decreased. Both the first and the secondincreases in activity in response to slicing and additionaltreatment with a hyphal wall component to elicit phytoalexinproduction were inhibited by blasticidin S. Properties of HMG-CoAreductase induced by slicing and by additional treatment withHgCl2 or fungal inoculation were investigated.
2 Present address: Faculty of Home Economics, Nagoya Women'sUniversity, Shioji-cho, Mizuho, Nagoya 467, Japan. 相似文献
10.
Andrzej Paszczyński Jan Fiedurek Zdzislaw Ilczuk Grażyna Ginalska 《Applied microbiology and biotechnology》1985,22(6):434-437
Summary Two proteases from Aspergillus niger C post-culture medium were isolated by fractionation on a DEAE-sepharose column and ultrafiltration. The four fractions of glucoamylase activity (GA1, GA2, GA3 and GA4) present in the medium showed different susceptibility to the influence of proteases. The effects of proteases on the different glucoamylase fractions during the growth of the fungus are demonstrated. The activity was found to decrease at the beginning of the culture, but by its end there was a stimulation of GA4 glucoamylase. After treating GA2 and GA3 with protease II, a new additional fraction of glucoamylase was detected. 相似文献