Stem photosynthesis widely presents in desert plants, which increases carbon uptake capacity. In this study, we measured the photosynthetic characteristics of leaves and stems in seven desert woody ...plants (Populus euphratica, Populus alba var. pyramidalis, Populus pruinose, Haloxylon ammodendron, Calligonum rubicundum, Calligonum caput-medusae, Ammopiptanthus mongolicus) in the same habitat, using a portable Li-6400XT photosynthesis system combined with P-Chamber. We analyzed stem photosynthetic rate and its relationship with leaf photosynthetic rate. We measured the stem functional traits, including water content, stem dry matter content, chlorophyll content, water potential, non-structure carbohydrate (NSC), etc., to find out the main affecting factors of stem photosynthesis. The results showed that stem photosynthetic rate of seven species ranged from 0.72 to 1.71 μmol·m-2·s-1, with the largest of P. pruinose and the smallest of H. ammodendron. Stem photosynthetic rate could offset CO2 of stem respiration
Changes in nitrogen (N) deposition and litter mixtures have been shown to influence ecosystem processes such as litter decomposition. However, the interactive effects of litter mixing and ...N‐deposition on decomposition process in desert regions remain poorly identified. We assessed the simultaneous effects of both N addition and litter mixture on mass loss in a litterbag decomposition experiment using six native plants in single‐species samples with diverse quality and 14‐species combinations in the Gurbantunggut Desert under two N addition treatments (control and N addition). The N addition had no significant effect on decomposition rate of single‐species litter (expect Haloxylon ammodendron), whereas litter mass loss and decomposition rate differed significantly among species, with variations positively correlated with initial phosphorus concentration and negatively correlated with initial lignin concentration. After 18 months, the average mass loss across litter mixtures did not overall differ from those predicted from single species either in control or N addition treatments, that is, mixing of different species had no non‐additive effects on decomposition. The N addition, however, did modify the direction of mixture effects and interacted with incubation time. Added N transformed synergistic effects of litter mixtures to antagonistic effects on mass loss after 1 month of decomposition, while transforming neutral effects of litter mixture to synergistic effects after 6 months of decomposition. Our results demonstrated that initial chemical properties played an important role in litter decomposition, while no effects of litter mixture on decomposition process in this desert region. The N addition altered the litter mixture effects on mass loss with incubation time, implying that increased N deposition in the future may have profound effects on carbon turnover to a greater extent than previously thought in desert ecosystems.
This paper demonstrated that the initial chemical properties played an important role in litter decomposition, while no effects of litter mixture on decomposition process in this desert region. The N addition altered the litter mixture effects on mass loss with incubation time, implying that increased N deposition in the future may have profound effects on carbon turnover to a greater extent than previously thought in desert ecosystems.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Stem photosynthesis (
) is an alternative and significant carbon source, playing a crucial role in plant survival under extreme environment. The main aims of this study were to quantify stem and leaf ...photosynthesis, find out the main drivers of
, and estimate the contributions of
to plant individual carbon balance of two dominant species
and
in Gurbantunggut Desert. A Li-Cor 6400 portable photosynthesis system and a special chamber were used to measure leaf and stem photosynthesis. Ancillary measurements included leaf/stem functional trait (chlorophyll content, water content, leaf/stem area, carbon/nitrogen content,
.) and environmental factors (air temperature and humidity, photosynthetically active radiation, soil temperature, and soil water content). Our results showed that
of
and
was 2.37 and 0.98 μmol·m
·s
,
refixation CO
of stem respiration by 65%-76% and 57%-77% in
and
.
was influenced by photosynthetically active radiation, air temperature, soil temperature and water vapor deficit.
assimilation CO
acc
Spatial variation is a ubiquitous feature of natural ecosystems, especially in arid regions, and is often present at various scales in these regions. To determine the scale dependence of the ...heterogeneity of soil chemical properties and the dominant scales （factors） for soil heterogeneity in arid regions, the spatial variability of soil resources was investigated in the Gurbantunggut Desert of Central Asia at the scales of 10-3, 10-2, 10-1, 100, 101, 102, 103 and 104 m （from individual plant to population or community to ecosystem）. Soil chemical properties including pH, electrical conductivity （EC）, organic carbon, total nitrogen, available nitrogen, total phosphorus, and available phosphorus were considered in the investigation. At a scale of 10-1 m, which represented the scale of individual plant, significant enrichment of soil resources occurred under shrub canopy and ＂fertile islands＂ formed in the desert ecosystem. Soil EC exhibited the largest heterogeneity at this scale, indicating that individual plants exerted a great influence on soil salinity/alkalinity. Soil nutrients exhibited the greatest heterogeneity at a scale of 102 m, which represented the scale of sand dune/interdune lowlands （between communities）. The main important factors contributing to soil spatial heterogeneity in the Gurbantunggut Desert were individual plants and different topographic characteristics, namely, the appearance of vegetation, especially shrubs or small trees, and existing sand dunes. Soil salinity/alkalinity and soil nutrient status behaved differently in spatial heterogeneity, with an inverse distribution between them at the individual scale.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We analyzed 314,254 soybean expressed sequence tags (ESTs), including 29,540 from our laboratory and 284,714 from GenBank. These ESTs were assembled into 56,147 unigenes. About 76.92% of the unigenes ...were homologous to genes from Arabidopsis thaliana ( Arabidopsis). The putative products of these unigenes were annotated according to their homology with the categorized proteins of Arabidopsis. Genes corresponding to cell growth and/or maintenance, enzymes and cell communication belonged to the slow-evolving class, whereas genes related to transcription regulation, cell, binding and death appeared to be fast-evolving. Soybean unigenes with no match to genes within the Arabidopsis genome were identified as soybean-specific genes. These genes were mainly involved in nodule development and the synthesis of seed storage proteins. In addition, we also identified 61 genes regulated by salicylic acid, 1,322 transcription factor genes and 326 disease resistance-like genes from soybean unigenes. SSR analysis showed that the soybean genome was more complex than the Arabidopsis and the Medicago truncatula genomes. GC content in soybean unigene sequences is similar to that in Arabidopsis and M. truncatula. Furthermore, the combined analysis of the EST database and the BAC-contig sequences revealed that the total gene number in the soybean genome is about 63,501.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
At present, the objective of cutting and pruning Cistanche deserticola is to harvest in successive years and enhance the harvesting yield and quality of C. deserticola in the process of the ...artificial cultivating C. deserticola. An experiment was conducted focusing on cutting and pruning C. deserticola in artificial forests of Haloxylon ammodendron drip-irrigated with saline water at the hinter-land of the Taklimakan desert, according to different growth stages and lengths. The results were following: (1) The effect of cutting on C. deserticola was similar to that of pruning, which resulted in three kinds of morphological types, not related to the bloom and size of C. deserticola. (2) The growth forms were diversified after pruning. Among them, there had sprouting new body, died or maintaining life with no sprouting, mildewed on its surface layer, etc. However, some of new bodies were sprouting from the lower part of the old body. The death rate of bloomed C. deserticola was higher than that of the underground, and the death rate of the 40 cm in stubble height for C. deserticola was higher than those with the stubble height of 20 cm and 5 cm. (3) Most of the diameter of living C. deserticola after pruning was increasing, but some of them changed little. (4) The mildew and rot of C. deserticola and the broken of the roots of the H. ammodendron and the fallen of the point of the inoculated when it was dug, which would cause the death of the C. deserticola. On the other, the yield-increasing effect and the economic benefit of the techniques of the pruning of Cistanche would need further research and evaluate. Therefore, the application of this technique needs to be cautious.
Packet loss is unavoidable in IP multicast using the UDP protocol that will serious influence video quality. In this paper we use the Raptor codes for video multicast to improve the video quality. ...Firstly, the principle of Raptor codes is analyzed in detail. Then the Raptor codes is implemented and transplanted in the video transmission system. Simulation results show that the video transmission system with Raptor FEC works which can overcome the packet loss effectively and improve the playback quality significantly.
Ecological stoichiometry is the study of the balance of multiple chemical elements in ecological interactions; it is the important content and hotspot in ecology research. Ecological stoichiometry ...plays an important role in determining plants and ecosystem nutrient supply and demand and their balance. The content of plant chemical element at different organs is restricted by the environmental nutrient availability, especially by the restricted nutrient, and it also affected by plant growth form, the physical characteristics and life history, which is the result of environment and species phylogenesis development together. Study on the plants leaf nutrient content and its variance in extreme environment is important in revealing the plants nutrient requirement and soil nutrient supply capacity, it is also important in revealing the plants adaptability to environment. This study was conducted for 25 artificial plants which from different family and life form in the hinterland of Taklimakan Desert, using variance analysis and correlation analysis together to determine the stoichiometric characteristics and its relationship for plant leaf and soil. The results showed that the mean content of artificial plants leaf C, N, P were (386.7 plus or minus 46.6), (24.7 plus or minus 8.1) and (1.8 plus or minus 0.78) mg/g respectively in Taklimakan Desert, leaf N was significantly higher than those plants which were not desert plants. C:N, C:P were (17.5 plus or minus 6.7), (249.2 plus or minus 102.8) respectively, which were lower than the average of global land plants, and indicated that extreme environment restricted the use of nutrient elements for artificial desert plants. And 14<N:P<16 (15.0 plus or minus 5.6), which indicated plants growth were restricted by N and P together in the study area. Also the N content for legume plants was greatly higher than non-legume plants indicating significant nitrogen fixation for legume plants. Great difference for leaf C, N, P content were presented in different life form plants were also obtained in this study, C, N and P content were also presented as herb>shrub>tree. There was no difference for C:N and N:P between different life forms, while the C:P for shrub and tree functional group were significantly higher than herb functional group. The correlation analysis indicated that leaf C:N, C:P were negatively correlated with N, P content significantly, while no correlation between leaf N and P. Soil nutrient content were significantly lower than other region, especially for soil N content (<0.2 mg/g), significantly positive correlation between soil C and N (P<0.01), and no correlation between soil C and P, N and P (P>0.05). In all, the above results documented that extreme environment of nutrient restricted area limited the plants' nutrients use efficiency, which may be the adaptive strategy for the artificial plants in extreme environments. Besides, different functional group had different adaptability to environment, and significantly nutrient adapt strategy diversity was presented in this study.
Objective The purpose of the present study was to observe the changes in CD4＋CD25＋Nrpl＋Treg cells after irradiation with different doses and explore the possible molecular mechanisms involved. ...Methods ICR mice and mouse lymphoma cell line （EL-4 cells） was used. The expressions of CD4, CD25, Nrpl, calcineurin and PKC-α were detected by flow cytometry. The expressions of TGF-131, IL-10, PKA and cAMP were estimated with ELISA. Results At 12 h after irradiation, the expression of Nrpl increased significantly in 4.0 Gy group, compared with sham-irradiation group （P〈0.05） in the spleen and thymus, respectively, when ICR mice received whole-body irradiation （WBI）. Meanwhile the synthesis of Interleukin 10 （IL-20） and transforming growth factor-β1 （TGF-β1） increased significantly after high dose irradiation （HDR） （〉 or = 1.0 Gy）. In addition, the expression of cAMP and PKA protein increased, while PKC-α, calcineurin decreased at 12h in thymus cells after 4.0 Gy X-irradiation. While TGF-β1 was clearly inhibited when the PLC-PIP2 signal pathway was stimulated or the cAMP-PKA signal pathway was blocked after 4.0 Gy X-irradiation, this did not limit the up-regulation of CD4＋CD25＋Nrpl＋Treg cells after ionizing radiation. Conclusion These results indicated that HDR might induce CD4＋CD25＋Nrpl＋Treg cells production and stimulate TGF-β1 secretion by regulating signal molecules in mice.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objective. This study aims to explore the relationships between serum indoxyl sulfate (IS) and Klotho protein levels with vascular calcification in patients with chronic kidney disease (CKD) stages ...3–5. Methods. From December 2021 to January 2023, a total of 108 CKD patients in stages 3–5 were enrolled in this cross-sectional investigation. Demographic information and routine clinical biochemistry test results were gathered. Serum levels of IS and Klotho were quantified through enzyme-linked immunosorbent assays. Furthermore, multislice spiral computed tomography was employed to evaluate vascular calcification. The association between serum IS or Klotho levels and abdominal aorta calcification was assessed using univariate analysis and logistic regression analyses. Results. With the progression of CKD stages, serum creatinine, phosphorus, intact parathyroid hormone (iPTH), serum IS, and abdominal aortic calcification exhibited incremental trends, while serum calcium and Klotho protein levels showed a diminishing trend, with statistically significant differences (P<0.05). Significant differences were observed in age, blood phosphorus, calcium, total parathyroid hormone, serum IS, and Klotho protein levels between patients with and without aortic calcification (P<0.05). Logistic regression analysis demonstrated that advanced age, high IS level, and low Klotho protein level were independent risk factors for abdominal aortic calcification in CKD patients (P<0.05). Conclusion. This study indicates elevated serum IS levels and decreased Klotho protein levels in CKD patients. High IS level and low Klotho level were independent risk factors for abdominal aortic calcification.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
