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21.
Vladimir A. Shuvalov 《BBA》2007,1767(6):422-433
It has been shown [V.A. Shuvalov, Quantum dynamics of electrons in many-electron atoms of biologically important compounds, Biochemistry (Mosc.) 68 (2003) 1333-1354; V.A. Shuvalov, Quantum dynamics of electrons in atoms of biologically important molecules, Uspekhi biologicheskoi khimii, (Pushchino) 44 (2004) 79-108] that the orbit angular momentum L of each electron in many-electron atoms is L = mVr = n? and similar to L for one-electron atom suggested by N. Bohr. It has been found that for an atom with N electrons the total electron energy equation E = −(Zeff)2e4m/(2n2?2N) is more appropriate for energy calculation than standard quantum mechanical expressions. It means that the value of L of each electron is independent of the presence of other electrons in an atom and correlates well to the properties of virtual photons emitted by the nucleus and creating a trap for electrons. The energies for elements of the 1st up to the 5th rows and their ions (total amount 240) of Mendeleev' Periodical table were calculated consistent with the experimental data (deviations in average were 5 × 10− 3). The obtained equations can be used for electron dynamics calculations in molecules. For H2 and H2+ the interference of electron-photon orbits between the atoms determines the distances between the nuclei which are in agreement with the experimental values. The formation of resonance electron-photon orbit in molecules with the conjugated bonds, including chlorophyll-like molecules, appears to form a resonance trap for an electron with E values close to experimental data. Two mechanisms were suggested for non-barrier primary charge separation in reaction centers (RCs) of photosynthetic bacteria and green plants by using the idea of electron-photon orbit interference between the two molecules. Both mechanisms are connected to formation of the exciplexes of chlorophyll-like molecules. The first one includes some nuclear motion before exciplex formation, the second one is related to the optical transition to a charge transfer state. 相似文献
22.
Douglas A. Burns 《Biogeochemistry》1998,40(1):73-96
Models of the effects of atmosphericN deposition in forested watersheds have notadequately accounted for the effects of aquatic andnear-stream processes on the concentrations and loadsof NO
in surface waters. This studycompared the relative effects of aquatic andnear-stream processes with those from the terrestrialecosystem on the retention and transport ofNO
in two contrasting stream reaches ofthe Neversink River, a forested watershed in theCatskill Mountains of New York that receives among thehighest load of atmospheric N deposition in thenortheastern United States. Stream water samples werecollected every two hours and ground-water andtributary samples were collected daily at base flowconditions during four 48-hour periods from April toOctober 1992, and NO
mass balances werecalculated for each site. Results indicated diurnalvariations in stream NO
concentrations inboth reaches during all four sampling periods; this isconsistent with uptake of NO
byphotoautotrophs during daylight hours. Mass-balanceresults revealed significant stream reach losses ofNO
at both sites during all samplingperiods. The diurnal variations in NO
concentrations and the retention of NO
relative to terrestrial contributions to the streamreaches were greater downstream than upstream becausephysical factors such as the head gradients ofinflowing ground water and the organic matter contentof sediment are more favorable to uptake anddenitrification downstream. The mass retention ofNO
increased as the mean 48-hr streamdischarge increased at each site, indicating that theresponsible processes are dependent onNO
supply. Low stream temperatures duringthe April sampling period, however, probably reducedthe rate of retention processes, resulting in smallerlosses of NO
than predicted from streamdischarge alone. Water samples collected from thestream, the hyporheic zone, and the alluvial groundwater at sites in both reaches indicated that the neteffect of hyporheic processes on downstreamNO
transport ranged from conservativemixing to complete removal by denitrification. Therelative effects of biological uptake anddenitrification as retention mechanisms could not bequantified, but the results indicate that bothprocesses are significant. These results generallyconfirm that aquatic and near-stream processes causesignificant losses of NO
in the NeversinkRiver, and that the losses by these processes atdownstream locations can exceed the NO
contributions to the stream from the terrestrialenvironment during summer and fall base-flowconditions. Failure to consider these aquatic andnear-stream processes in models of watershed responseto atmospheric N deposition could result inunderestimates of the amount of NO
leaching from forested ecosystems and to an inabilityto unequivocally relate geographic differences inNO
concentrations of stream waters tocorresponding differences in terrestrial processes. 相似文献
23.
《Journal of Asia》2022,25(2):101880
Bioassays to evaluate the mortality, virulence and reproduction potentials of four indigenous EPN strains, S-PQ16, S-BM12, H-KT3987 and H-CB3452 on insect larvae of mealworm (Tenebrio molitor) and greater wax moth (Galleria mellonella) revealed the highest mortality rates of two insect larvae at the highest inoculation dose of 100 IJs to range from 89 to 100 percent and 94.3–100 percent at 48 h after inoculation, respectively. Virulence was high for all nematode strains, with LC50 values between 29.6 and 47.3 IJs/insect host. The highest IJ yields were different between nematode strains and insect host, from 66.8 × 103 IJs (S-PQ16) to 118.6 × 103 IJs (H-KT3987) on T. molitor, and from 54.2 × 103 IJs (S-BM12) to 163.3 × 103 IJs (H-KT3987) on G. mellonella. The culturing cost in terms of food expenditure for rearing insect larvae varied between insect larvae and nematode strains, from 6.76 to 26.63 USD per billion IJs for nematode strains cultured on T. molitor larvae and from 3.54 to 7.81 USD per billion IJs for nematode strains cultured on G. mellonella larvae. The full cost for a nematode product of 2.5 × 109 IJs per hectare, produced through in vivo mass culturing, of the most efficient nematode strain, H-KT3987, was 191.3 USD, slightly cheaper than 199.4 USD for the same nematode product produced through in vitro mass culturing. 相似文献
24.
Liping Wang;Junjie Wu;Yong Chai;Jiwen Sun;Xiaoli Yu;Zhe Feng;Fengxian Chen; 《Ecology and evolution》2024,14(7):e11675
Density dependence and habitat filtering have been proposed to aid in understanding community assembly and species coexistence. Phylogenetic relatedness between neighbors was used as a proxy for assessing the degree of ecological similarity among species. There are different conclusions regarding the neighborhood effect in previous studies with different phylogenetic indices or at different spatiotemporal scales. However, the effects of density dependence, neighbor phylogenetic relatedness, and habitat filtering on seedling survival with different phylogenetic indices or at different temporal and spatial scales are poorly understood. We monitored 916 seedlings representing 56 woody plant species within a 4-ha forest dynamics plot for 4 years (from 2020 to 2023) in a subtropical mid-mountain moist evergreen broad-leaved forest in the Gaoligong Mountains, Southwestern China. Using generalized linear mixed models, we tested whether and how four phylogenetic indices: total phylogenetic distance (TOTPd), average phylogenetic distance (AVEPd), relative average phylogenetic distance (APd′), and relative nearest taxon phylogenetic distance (NTPd′), three temporals (1, 2, and 3 years), and spatial scales (1, 2, and 4 ha) affect the effect of density dependence, phylogenetic density dependence, and habitat filtering on seedling survival. We found evidence of the effect of phylogenetic density dependence in the 4-ha forest dynamics plot. The effects of density dependence, phylogenetic density dependence, and habitat filtering on seedling survival were influenced by phylogenetic indices and temporal and spatial scales. The effects of phylogenetic density dependence and habitat filtering on seedling survival were more conspicuous only at 1-year intervals, compared with those at 2- and 3-year intervals. We did not detect any effects of neighborhood or habitat factors on seedling survival at small scales (1 and 2 ha), although these effects were more evident at the largest spatial scale (4 ha). These findings highlight that the effects of local neighborhoods and habitats on seedling survival are affected by phylogenetic indices as well as temporal and spatial scales. Our study suggested that phylogenetic index APd′, shortest time scale (1 year), and largest spatial scales (4 ha) were suitable for neighborhood studies in a mid-mountain moist evergreen broad-leaved forest in Gaoligong Mountains. Phylogenetic indices and spatiotemporal scales have important impacts on the results of the neighborhood studies. 相似文献
25.
We herein report the design, synthesis and molecular docking studies of 2,4-thiazolidinedione derivatives containing benzene sulphonyl group which are docked against the Peroxisome Proliferator Activated Receptor (PPARγ) target. Compound 7p was most effective in lowering the blood glucose level as compared to standard drugs pioglitazone and rosiglitazone. Compound 7p exhibited potent PPAR-γ transactivation of 61.2% with 1.9 folds increase in gene expression. In molecular docking studies 7p showed excellent interactions with amino acids TYR 473, SER 289, HIE 449, TYR 327, ARG 288, MET 329 and LEU 228. Compound 7p did not cause any damage to the liver without any noteworthy weight gain and may be considered as promising candidates for the development of new antidiabetic agents. 相似文献
26.
Robert D. Dorn 《Brittonia》2003,55(1):1-3
A new species,Boechera glareosa, is described and a key is provided to separate it from its apparent closest relative,B. gunnisoniana (Rollins) W. A. Weber. Twelve transfers are made fromArabis toBoechera to bring the nomenclature of Rocky Mountain region taxa in line with current DNA data. 相似文献
27.
Although the adder (Vipera berus) has a large distribution area, this species is particularly threatened in Western Europe due to high habitat fragmentation
and human persecution. We developed 13 new microsatellite markers in order to evaluate population structure and genetic diversity
in the Swiss and French Jura Mountains, where the species is limited to only a few scattered populations. We found that V. berus exhibits a considerable genetic differentiation among populations (global FST = 0.269), even if these are not geographically isolated. Moreover, the genetic diversity within populations in the Jura Mountains
and in the less perturbed Swiss Alps is significantly lower than in other French populations, possibly due to post-glacial
recolonisation processes. Finally, in order to minimize losses of genetic diversities within isolated populations, suggestions
for the conservation of this species in fragmented habitats are proposed. 相似文献
28.
The moose (Alces alces cameloides) population in northeastern China is on the southernmost edge of its distribution in Asia. A survey was conducted to determine
moose resource selection and the effects of human disturbance on moose in a study area of 20,661 ha located on the northwestern
slope of the Lesser Khingan Mountains, located in northeastern China. Predictive models of resource selection were developed
using logistic and autologistic regression. All models considered resource variable selection at two spatial scales, patch
and landscape. At the patch scale, moose preferred larger birch (Betula platyphylla) patches, but avoided larger tamarack (Larix gmelinii) patches. At the landscape scale, moose preferred higher densities of tamarack patches, i.e., heterogeneity of tamarack stands,
selected areas with more abundant annual shoots, terrain conducive to better concealment, higher altitudes and areas saturated
with soil moisture. Roads and forest harvest intervals were identified as important human disturbance factors. This is the
first time that moose have been reported to avoid roads, and the avoidance distance was nearly 3 km. We believe that in this
region moose under the influence of roads are behaviorally plastic, compared with the indifference of moose to the presence
of roads in other regions. Moose avoided forest areas logged more than 3 years previously and preferred areas logged 1–2 years
previously. In addition, it may be necessary to monitor the effect of the dynamic of density of roe deer on the spatial distribution
of the moose population. 相似文献
29.
Feces of wild chimpanzees in the Mahale Mountains, Tanzania, were inspected for intestinal parasites under a compound microscope.
Eggs or larvae ofOesophagostomum, Strongyloides, Trichuris, Prosthenorchis, andBertiella were found. Intestinal nematodes significantly increased in the mid-rainy season. This finding supports (or, at least, is
not in conflict with) the hypothesis thatAspilia leaves which are occasionally swallowed by chimpanzees may function as a vermicide, since ingestion of such leaves also increases
significantly in the mid-rainy season. 相似文献
30.
Winsor H. Lowe;Brett R. Addis;Madaline M. Cochrane; 《Molecular ecology》2024,33(12):e17375
Assessing direct fitness effects of individual genetic diversity is challenging due to the intensive and long-term data needed to quantify survival and reproduction in the wild. But resolving these effects is necessary to determine how inbreeding and outbreeding influence eco-evolutionary processes. We used 8 years of capture–recapture data and single nucleotide polymorphism genotypes for 1906 individuals to test for effects of individual heterozygosity on stage-specific survival probabilities in the salamander Gyrinophilus porphyriticus. The life cycle of G. porphyriticus includes an aquatic larval stage followed by metamorphosis into a semi-aquatic adult stage. In our study populations, the larval stage lasts 6–10 years, metamorphosis takes several months, and lifespan can reach 20 years. Previous studies showed that metamorphosis is a sensitive life stage, leading us to predict that fitness effects of individual heterozygosity would occur during metamorphosis. Consistent with this prediction, monthly probability of survival during metamorphosis declined with multi-locus heterozygosity (MLH), from 0.38 at the lowest MLH (0.10) to 0.06 at the highest MLH (0.38), a reduction of 84%. Body condition of larvae also declined significantly with increasing MLH. These relationships were consistent in the three study streams. With evidence of localised inbreeding within streams, these results suggest that outbreeding disrupts adaptations in pre-metamorphic and metamorphic individuals to environmental gradients along streams, adding to evidence that headwater streams are hotspots of microgeographic adaptation. Our results also underscore the importance of incorporating life history in analyses of the fitness effects of individual genetic diversity and suggest that metamorphosis and similar discrete life stage transitions may be critical periods of viability selection. 相似文献