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1.
Sci Total Environ ; 924: 171611, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38462013

ABSTRACT

The study on the water source of plants in alpine mountainous is of great significance to optimize the allocation and management of water resources, and can also provide important reference for ecological restoration and protection. However, the controls of water sources for different plants in alpine mountainous region remain poorly understood. Based on the advantages of stable isotope tracer and Bayesian (MixSIAR) model, the water source of plants in Qilian Mountains was quantitatively analyzed. The results showed that the water sources of plants in Qilian Mountain mainly included two parts: direct source and indirect source. The direct source is soil water, which provides most of the water that plants need. The highest contribution of soil water to shrubs was 80 %, followed by trees (73 %) and herbs (72 %). It is worth mentioning that trees mainly use deeper soil water (below 60 cm), shrubs mainly use surface and intermediate soil water (0-60 cm), and herbs mainly use surface soil water (0-40 cm). What is more noteworthy is that indirect sources, such as precipitation, glacier and snow meltwater, and groundwater, are also water sources that cannot be ignored for plant growth in study area. Shrubs and Herbs use more soil water in the range of 40-60 cm, which leads to the possibility of water competition between these two planting types. Therefore, attention should be paid to this phenomenon in the process of vegetation restoration and water resources management. Especially when planting or restoring artificial plants, it is necessary to consider the water use strategy of the two plants to avoid unnecessary water competition and water waste. This is of great significance for ecological stability and sustainable utilization of water resources in the study region.


Subject(s)
Groundwater , Water , Bayes Theorem , Water Resources , Plants , Soil , China
2.
J Environ Manage ; 356: 120536, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38492421

ABSTRACT

Due to the continuous degradation (gradual thawing) of permafrost, supra-permafrost water has become an important component of runoff that occurs in cold regions. However, current research has only focused on the amount of water provided by permafrost, and little has been reported regarding the source and formation mechanisms of supra-permafrost water. Due to the difficulty of observation and sampling in cold regions and insufficient data accumulation, model simulations face various difficulties in regard to solving problems related to hydrological processes. Considering the advantages of stable isotope tracer methods in hydrology, the source of supra-permafrost water in Qilian Mountain was analyzed based on 1,840 samples, and the source of supra-permafrost water was determined by end-member mixing analysis (EMMA). Negative line-conditioned excess (lc-excess), lower slope, and particularly the negative intercept of the evaporation line (EL) indicates strong evaporation effects on supra-permafrost water. Remarkably, the evolutionary process, influencing factors, and relationship with other water bodies all indicate that supra-permafrost water is replenished by precipitation, ground ice meltwater, and snow meltwater. The results indicated that from May to October, the contributions of precipitation to the supra-permafrost water were 79%, 83%, 90%, 84%, 87%, and 83%, respectively. Snow meltwater contributed 11%, 13%, 10%, 16%, 11%, and 9%, respectively. Permafrost degradation impacts the water cycle and can increase the minimum monthly runoff and increase groundwater storage. To mitigate the effects of this change, monitoring and early warning systems are essential for detecting signs of permafrost degradation in a timely manner so that appropriate measures can be taken. This may involve the use of remote-sensing technologies, sensor networks, and other methods for real-time monitoring. Establishing mechanisms for sharing information with the relevant departments is crucial. The research results provide scientific and technological support and aid in decision-making to mitigate the negative effects of continuous permafrost degradation in a changing environment.


Subject(s)
Groundwater , Permafrost , Water , Isotopes , Freezing
3.
J Environ Manage ; 342: 118198, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37270977

ABSTRACT

Drastic changes in the cryosphere have a significant impact on the quantity and formation process of water resources in the Qilian Mountains. The present study focused on quantitative evaluation of runoff components and runoff formation processes during strong ablation periods (August), in 2018, 2020, and 2021, in the transition zone between endorheic and exorheic basins in China, based on 1906 stable isotope samples. The results revealed that as the altitude decreased, the contribution of glacier and snow meltwater and permafrost water to runoff decreased, whereas that of the precipitation increased. Precipitation is a major source of river runoff in the Qilian Mountains. Notably, the runoff yield and concentration of rivers that were greatly affected by the cryosphere exhibited the following characteristics: (1) The altitude effect of stable isotopes was not significant and even showed a reverse trend in some rivers. (2) The processes of runoff yield and composition were relatively slow; as such, precipitation, glacier and snow meltwater, and supra-permafrost water were first transformed into groundwater and then supplied runoff to upstream mountainous region. (3) Finally, stable isotope composition in such rivers were similar to those in glaciers and snow meltwater, with small fluctuations. Therefore, the water sources of rivers affected by the cryosphere are more uncertain than those of rivers unaffected by the cryosphere. In future study, a prediction model of extreme precipitation and hydrological events will be developed, and a prediction technology for runoff formation and evolution in glacier snow and permafrost will be developed to integrate short-and long-term forecasts.


Subject(s)
Groundwater , Isotopes , Water Resources , Snow , Rivers , Water , Environmental Monitoring/methods
4.
Tob Induc Dis ; 20: 57, 2022.
Article in English | MEDLINE | ID: mdl-35799621

ABSTRACT

INTRODUCTION: Serum cotinine is a sensitive and specific marker of tobacco smoke exposure. α-Klotho is an anti-ageing molecule, which plays an important role in several diseases. We aimed to examine the association between smoke exposure indicated by the serum cotinine and α-Klotho levels, as previous reports regarding the level of α-Klotho in smokers have been inconsistent. METHODS: This secondary dataset analysis included 9833 participants (aged 40-79 years; 47.0% females and 53.0% males) from the US National Health and Nutrition Examination Survey 2007-2016. Independent variables were serum cotinine level, age, sex, race, body mass index (BMI), and alcohol consumption. The outcome variable was serum α-Klotho level. Multiple linear regression analysis was used to examine the association between serum cotinine and α-Klotho levels. RESULTS: The serum cotinine level was negatively associated with the α-Klotho level (ß= -0.107, 95% CI: -0.155 to -0.059, p<0.0001) after adjusting for age, BMI, sex, race, and alcohol consumption. The α-Klotho level in participants with cotinine ≥3 ng/mL decreased by 44.514 pg/mL (p<0.0001) compared to that in participants with cotinine <3 ng/mL. There is a non-linear relationship between serum cotinine and α-Klotho levels. The piecewise linear models indicated a significant threshold effect between serum cotinine and α-Klotho levels. On the left of the inflection point (cotinine <130 ng/mL), the serum cotinine level increased with decreased α-Klotho level (ß= -0.519, 95% CI: -0.682 to -0.356). On the right of the inflection point (cotinine ≥130 ng/mL), the serum cotinine level increased with increased α-Klotho level (ß=0.085, 95% CI: 0.000 to 0.170). CONCLUSIONS: Based on our study results, serum cotinine level was associated with the serum α-Klotho level.

5.
Curr Microbiol ; 73(4): 595-601, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27449214

ABSTRACT

High-throughput sequencing technology was used to reveal the composition and distribution of fungal community structure in the Yellow River Delta under bare land and four kinds of halophyte vegetation (saline seepweed, Angiospermae, Imperata and Apocynum venetum [A. venetum]). The results showed that the soil quality continuously improved with the succession of salt vegetation types. The soil fungi richness of mild-salt communities (Imperata and A. venetum) was relatively higher, with Shannon index values of 5.21 and 5.84, respectively. The soil fungi richness of severe-salt-tolerant communities (saline seepweed, Angiospermae) was relatively lower, with Shannon index values of 4.64 and 4.66, respectively. The UniFrac metric values ranged from 0.48 to 0.67 when the vegetation was in different succession stages. A total of 60,174 valid sequences were obtained for the five vegetation types, and they were classified into Ascomycota, Basidiomycota, Chytridiomycota, Glomeromycota and Mucoromycotina. Ascomycota had the greatest advantage among plant communities of Imperata and A. venetum, as indicated by relative abundances of 2.69 and 69.97 %, respectively. Basidiomycota had the greatest advantage among mild-salt communities of saline seepweed and Angiospermae, with relative abundances of 9.43 and 6.64 %, respectively. Soil physical and chemical properties were correlated with the distribution of the fungi, and Mucor was significantly correlated with soil moisture (r = 0.985; P < 0.01). Soil quality, salt vegetation and soil fungi were influenced by each other.


Subject(s)
Biodiversity , Fungi/isolation & purification , Rivers/microbiology , Salt-Tolerant Plants/microbiology , Sodium Chloride/metabolism , Soil Microbiology , Fungi/classification , Fungi/metabolism , Phylogeny , Salt-Tolerant Plants/growth & development , Soil/chemistry
6.
Opt Express ; 21(16): 19097-102, 2013 Aug 12.
Article in English | MEDLINE | ID: mdl-23938824

ABSTRACT

A compact fiber-optic vector rotation sensor in which a short section of polarization-maintaining (PM) fiber stub containing a straight fiber Bragg grating (FBG) is spliced to another single mode fiber without any lateral offset is proposed and experimentally demonstrated. Due to the intrinsic birefringence of the PM fiber, two well-defined resonances (i.e. orthogonally polarized FBG core modes) with wavelength separation of 0.5 nm have been achieved in reflection, and they exhibit a high sensitivity to fiber rotation. Both the orientation and the angle of rotation can be determined unambiguously via simple power detection of the relative amplitudes of the orthogonal core reflections. Meanwhile, instead of using a broadband source (BBS), the sensor is powered by a commercial vertical cavity surface emitting laser (VCSEL) with the laser wavelength matched to the PM-FBG core modes, which enables the sensor to work at much higher power levels (~15 dB better than BBS). This improves the signal-to-noise ratio considerably (~50 dB), and makes a demodulation filter unnecessary. Vector rotation measurement with a sensitivity of 0.09 dB/deg has been achieved via cost-effective single detector real time power measurement, and the unwanted power fluctuations and temperature perturbations can be effectively referenced out.

7.
J Biochem Mol Toxicol ; 27(11): 492-8, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23918508

ABSTRACT

Major histocompatibility complex (MHC) class I chain-related protein A (MICA) is involved in γδ T-cell recognition of target tumor cells. The aim of this study was to investigate the feasibility of utilization of sodium valproate (VPA), a histone deacetylase inhibitor, to sensitize non-small cell lung cancer A549 cells to γδ T-cell-mediated killing. VPA induced a dose-dependent increase in the mRNA and protein expression of MICA in A549 cells. γδ T cells showed cytotoxicity to A549 cells, which was increased by about 50% in the presence of VPA. The concomitant addition of MICA antibody significantly attenuated the VPA-mediated sensitization to γδ T-cell killing. VPA enhanced the cleavage of caspase-3 and caspase-9 in A549 cells cocultured with γδ T cells, and such enhancement was reversed by the MICA antibody. In conclusion, VPA sensitizes tumor cells to γδ T-cell-mediated cytotoxicity through the upregulation of MICA and may thus have benefits in improving γδ T-cell-based cancer immunotherapy.


Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , Histocompatibility Antigens Class I/biosynthesis , T-Lymphocytes, Cytotoxic/immunology , Valproic Acid/administration & dosage , Carcinoma, Non-Small-Cell Lung/immunology , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Histocompatibility Antigens Class I/genetics , Humans , Immunotherapy , T-Lymphocytes, Cytotoxic/drug effects
8.
Mol Med Rep ; 7(5): 1597-602, 2013 May.
Article in English | MEDLINE | ID: mdl-23483126

ABSTRACT

Macrophages are the target cells for Mycobacterium tuberculosis (M. tuberculosis) as well as key effector cells for clearance of this pathogen. The aim of the present study was to measure and compare the responses of mouse peritoneal macrophages following exposure to the live M. tuberculosis H37Ra and heat-inactivated H37Rv strains. In vitro phagocytosis assays indicated that the macrophages had a higher capacity to engulf the live H37Ra strain compared to the inactivated H37Rv strain. Enzyme-linked immunosorbent assay (ELISA) demonstrated that H37Ra­stimulated macrophages produced significantly increased concentrations of interleukin­12p40 (IL­12p40), tumor necrosis factor-α (TNF­α) and interferon­Î³ (IFN­Î³) compared to the untreated control cells. However, H37Rv exposure induced little to no increase in the levels of the cytokines examined. The results from ELISA were confirmed by reverse transcription-polymerase chain reaction (RT­PCR) at the mRNA level. There was a dose-dependent increase in nitric oxide (NO) and hydrogen peroxide (H2O2) production from the H37Ra­stimulated macrophages compared to the H37Rv­stimulated ones. Confocal microscopy and flow cytometric analysis indicated that the IFN­Î³­stimulated macrophages from viable H37Ra­immunized mice had an enhanced surface expression of CD40 ligand (CD40L) compared to those from inactivated H37Rv­immunized mice. Our data collectively indicate that exposure to the viable H37Ra strain induces a stronger macrophage response compared to exposure to the heat-inactivated H37Rv strain, which may be associated with the increased surface expression of CD40L in activated macrophages.


Subject(s)
Hot Temperature , Macrophages, Peritoneal/immunology , Macrophages, Peritoneal/microbiology , Microbial Viability/immunology , Mycobacterium tuberculosis/immunology , Animals , CD40 Ligand/metabolism , Cell Membrane/metabolism , Gene Expression Regulation , Hydrogen Peroxide/metabolism , Interferon-gamma/genetics , Interferon-gamma/metabolism , Interleukin-12 Subunit p40/genetics , Interleukin-12 Subunit p40/metabolism , Macrophages, Peritoneal/metabolism , Mice , Mice, Inbred BALB C , Microbial Viability/genetics , Nitric Oxide/metabolism , Phagocytosis/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
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