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991.
In the present study Cervatana and Almagra models from decision support system, MicroLEIS DSS, were applied to segregation
of arable land surfaces from the marginal ones and suitability evaluation of wheat (Triticum aestivum), maize (Zea mays) and alfalfa (Medicago sativa) in Souma area with approximately 4100 ha extension in West Azarbaijan. Obtained results from both models are presented and
discussed in this research work. Soil morphological and analytical data were collected from 35 soil profiles, representative
of the study area and stored in SDBm plus database. The control or vertical section of soil for applying and running the models
for annual selected crops, was calculated by soil layer generator 0.0–50 cm in depth, or between the surface and the limit
of useful depth when the latter is between 0.0 and 50 cm. According to results, 80.49% of the total area was good capable
for agricultural uses and 19.51% must be reforested and not dedicated to agriculture. The lands with good capability for agricultural
uses is classified as highly suitable area (S2) for wheat, maize and alfalfa, but results in 822 ha for maize and in 126 ha
for alfalfa refers to an excellent suitable (S1) and moderately suitable (S3) classes respectively. The most important limitation
factors are soil texture and carbonate alone or together and maize — wheat — alfalfa can be selected as the best crop rotation.
A simple map subsystem (ArcView GIS) was used for basic data and models result demonstration on a map. 相似文献
992.
KOJI NAKANISHI STEVEN BLOBSTEIN MAKOTO FUNAMIZU NOBUO FURUTACHI GEORGE VAN LEAR DEZIDER GRUNBERGER KARL W. LANKS I. BERNARD WEINSTEIN 《Nature: New biology》1971,234(47):107-109
WE wish to report that reconstituted sperm whale myoglobin prepared by the method of Breslow1 (except that pH 2 was found sufficient to remove all the haem) (I) crystallizes2 in a different habit from those prepared by the method of Rossi-Fanelli et al.3 (II) using haemin of Sigma lot 77B-0220 and our own 57Fe photoporphyrin preparation and the native myoglobin (III). Although all three form type A3 monoclinic prisms, the best developed plane is [001] for II and III, it is [100] for I. There seems to be great interest in reconstituted haemoproteins4,5, so it is important that crystallization habit may be a sensitive test for subtle changes in protein structures. 相似文献
993.
Transactive response DNA/RNA-binding protein 43-kDa (TDP-43) C-terminal fragments, such as a 25-kDa fragment (TDP-25), have been identified as a ubiquitinated and phosphorylated components of inclusion bodies (IBs) in motor neurons from amyotrophic lateral sclerosis patients. Cells contain proteins that function as molecular chaperones and prevent aggregate formation of misfolded and aggregation-prone proteins. Recently, we reported that heat shock protein (HSP)70, an abundant molecular chaperone, binds to TDP-25 in an ATP-dependent manner; however, whether HSP70 can prevent the formation of TDP-25-related IBs remains unknown. Here, we showed that HSP70 prevented TDP-25 aggregation according to green fluorescent protein-tagged TDP-25 (G-TDP-25) colocalization in the cytoplasm with mCherry-tagged HSP70 (HSP70-R). The mobile fraction of HSP70-R in the cytoplasmic IBs associated with G-TDP-25 increased relative to that of G-TDP-25, suggesting that HSP70 strongly bound to G-TDP-25 in the IBs, whereas a portion remained dissociated from the IBs. Importantly, the proportion of G-TDP-25 IBs was significantly decreased by HSP70-R overexpression; however, G-TDP-25 levels in the insoluble fraction remained unchanged by HSP70-R overexpression, suggesting that G-TDP-25 formed aggregated species that cannot be dissolved, even in the presence of strong detergents. These results indicated that HSP70 prevented the accumulation of G-TDP-25 aggregates in cytoplasmic IBs, but was insufficient for G-TDP-25 disassembly and solubilization. 相似文献
994.
Yuzuru Matsuda Teruhiko Beppu Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(6):1179-1186
The Oxygen activating mechanism of Fusarium lipoxygenase, a heme-containing dioxygenase, was studied. The enzyme did not require any cofactors, such as H2O2, however, both superoxide dismutase and catalase inhibited linoleate peroxidation by Fusarium lipoxygenase. A low concentration of H2O2 caused a distinct acceleration in enzymatic peroxidation. These results indicate that both O2? and H2O2 are produced as essential intermediates of oxygen activation during formation of linoleate hydroperoxides by Fusarium lipoxygenase. This peroxidation reaction was also prevented by scavengers of singlet oxygen (1O2), but not by scavengers of hydroxy 1 radical (OH). Generation of O2? in the enzyme reaction was detected by its ability to oxidize epinephrine to adrenochrome. Moreover, the rate of peroxide formation was greater in the D2O than in the H2O buffer system. These results suggest that the Haber–Weiss reaction (O2?+H2O2→OH?+OH·+1O2) is taking part in linoleate peroxidation by Fusarium lipoxygenase, and the 1O2 evolved could be responsible for the peroxidation of linoleate. H2O2 produced endogenously in the enzyme reaction might act as an activating factor for the enzyme. This possible mechanism of oxygen activation can explain the absence of a need for exogenous cofactors with Fusarium lipoxygenase in contrast to an other heme-containing dioxygenase, tryptophan pyrrolase, which requires an exogenous activating factor, such as H2O2. 相似文献
995.
Baker PJ Costanzo JP Lee RE 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2007,177(8):875-883
Hatchlings of the painted turtle, Chrysemys picta, hibernate terrestrially and can survive subfreezing temperatures by supercooling or by tolerating the freezing of their
tissues. Whether supercooled or frozen, an ischemic hypoxia develops because tissue perfusion is limited by low temperature
and/or freezing. Oxidative stress can occur if hatchlings lack sufficient antioxidant defenses to minimize or prevent damage
by reactive oxygen species. We examined the antioxidant capacity and indices of oxidative damage in hatchling C. picta following survivable, 48 h bouts of supercooling (−6°C), freezing (−2.5°C), or hypoxia (4°C). Samples of plasma, brain, and
liver were collected after a 24 h period of recovery (4°C) and assayed for Trolox-equivalent antioxidant capacity (TEAC),
thiobarbituric acid reactive substances (TBARS), and carbonyl proteins. Antioxidant capacity did not vary among treatments
in any of the tissues studied. We found a significant increase in TBARS in plasma, but not in the brain or liver, of frozen/thawed
hatchlings as compared to untreated controls. No changes were found in the concentration of TBARS or carbonyl proteins in
supercooled or hypoxia-exposed hatchlings. Our results suggest that hatchling C. picta have a well-developed antioxidant defense system that minimizes oxidative damage during hibernation. 相似文献
996.
997.
Habitat fragmentation is known to generally reduce the size of plant populations and increase their isolation, leading to
genetic erosion and increased between-population genetic differentiation. In Flanders (northern Belgium) Primula vulgaris is very rare and declining. Populations have incurred strong fragmentation for the last decades and are now restricted to
a few highly fragmented areas in an intensively used agricultural landscape. Previous studies showed that small populations
of this long-lived perennial herb still maintained high levels of genetic variation and low genetic differentiation. This
pattern can either indicate recent gene flow or represent historical variation. Therefore, we used polymorphic microsatellite
loci to investigate genetic variation and structure in adult (which may still reflect historical variation) and seedling (recent
generation, thus affected by current processes) life stages. The recent generation (seedlings) showed a significant loss of
observed heterozygosity (H
o) together with lower expected heterozygosity (H
e), a trend for higher inbreeding levels (F
IS) and higher differentiation (F
ST) between populations compared to the adult generation. This might result from (1) a reduction in effective population size,
(2) higher inbreeding levels in the seedlings, (3) a higher survival of heterozygotes over time due to a higher fitness of
heterozygotes (heterosis) and/or a lower fitness of homozygotes (inbreeding depression), (4) overlapping generations in the
adult life stage, or (5) a lack of establishment of new (inbred) adults from seedlings due to degraded habitat conditions.
Combining restoration of both habitat quality and gene flow between populations may be indispensable to ensure a sustainable
conservation of fragmented populations. 相似文献
998.
Binu Timsina Maan B. Rokaya Zuzana Münzbergová Pavel Kindlmann Bikram Shrestha Bishnu Bhattarai Bhakta B. Raskoti 《Biodiversity and Conservation》2016,25(13):2803-2819
Associations between epiphytes and their hosts are among the main factors affecting the biodiversity and distribution of epiphytes. While several previous studies explored the association between epiphyte diversity and host characteristics, very little is known about the generality of such associations at larger spatial scales. We aim to explore the associations between diversity and distribution of epiphytic orchids and host characteristics in different localities in Nepal. Epiphytic orchids and their hosts were recorded along the transects in total of 23,539 host individuals. To describe the diversity of orchids in the different localities, a rarefaction function was used. Univariate and multivariate analyses were carried out to explore the associations with locality, host characteristics, and their interactions with locality. In total, we recorded 141 species of orchids growing on 192 host species. The five localities significantly differed in orchid diversity and abundance. The number of orchid individuals per host species significantly increased with increasing number of host individuals. Species richness, abundances, occupancy of orchid species on host species and composition of orchids varied across the localities. Species richness and abundance was significantly higher on hosts in the higher strata and differed between families of host species. Abundance was higher on evergreen hosts. Composition of orchid communities are also associated with host characteristics, such as habit (shrub/tree/climber), bark texture, nature (deciduous/evergreen) and the plant families of host species. This study revealed a high diversity of epiphytic orchids in the localities studied and strong associations between the orchids and their hosts. Future studies looking at the relationships between epiphyte communities and host characteristics need to identify relationships at a wider scale in order to determine whether they are really general rather than site-specific. 相似文献
999.
Sara Diana Leonhardt Andreas Simon Brandstaetter Christoph Johannes Kleineidam 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(9):993-1000
Ants use cuticular hydrocarbons (CHC-profiles) as multicomponent recognition cues to identify colony members (nestmates).
Recognition cues (label) are thought to be perceived during ant–ant encounters and compared to a neuronal template that represents
the colony label. Over time, the CHC-profile may change, and the template is adjusted accordingly. A phenotype mismatch between
label and template, as happens with CHC-profiles of foreign workers (non-nestmates), frequently leads to aggressive behavior.
We investigated the template reformation in workers of the carpenter ant Camponotus floridanus by masking their antennae with postpharyngeal gland (PPG) extracts from nestmates or non-nestmates. The behavioral response
of manipulated workers encountering unmanipulated workers was measured independently after 2 and after 15 h. After 2 h of
incubation, workers treated with either of the two PPG-extracts showed low aggression towards nestmates and high aggression
towards non-nestmates. In contrast, after 15 h of incubation, workers treated with non-nestmate PPG-extract showed low aggression
towards both nestmates and non-nestmates. The slow (>2 h) adjustment of the template indicates a reformation localized in
the central nervous system rather than in chemosensory neurons. In addition, our data show that template adjustment to a new
CHC-profile does not impair the assessment of the old CHC-profile as nestmate label. 相似文献
1000.
Ping Xu Xinhua Cai Wenbo Zhang Yana Li Peiyong Qiu Dandan Lu Xiaoyang He 《Apoptosis : an international journal on programmed cell death》2016,21(10):1125-1143
The objective of our study was to assess the radioprotective effect of flavonoids extracted from Rosa roxburghii Tratt (FRT) and investigate the role of Bcl-2(Ca2+)/Caspase-3/PARP-1 pathway in radiation-induced apoptosis. Cells and mice were exposed to 60Co γ-rays at a dose of 6 Gy. The radiation treatment induced significant effects on tissue pathological changes, apoptosis, Ca2+, ROS, DNA damage, and expression levels of Bcl-2, Caspase-3 (C-Caspase-3), and PARP-1. The results showed that FRT acted as an antioxidant, reduced DNA damage, corrected the pathological changes of the tissue induced by radiation, promoted the formation of spleen nodules, resisted sperm aberration, and protected the thymus. FRT significantly reduced cell apoptosis compared with the irradiation group. The expression of Ca2+ and C-Caspase-3 was decreased after FRT treatment compared with the radiation-treated group. At the same time, expression of prototype PARP-1 and Bcl-2 increased, leading to a decrease in the percentage of apoptosis cells in FRT treatment groups. We conclude that FRT acts as a radioprotector. Apoptosis signals were activated via the Bcl-2(Ca2+)/Caspase-3/PARP-1 pathway in irradiated cells and FRT inhibited this pathway of apoptosis by down-regulation of C-Caspase-3 and Ca2+ and up-regulation of prototype PARP-1 and Bcl-2. 相似文献