149 results on '"YA-FENG ZHANG"'
Search Results
2. Experimental Study on the Evolution Mechanism of Landslide with Retaining Wall Locked Segment
- Author
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Han-Dong Liu, Jia-Xing Chen, Zhi-Fei Guo, Dong-Dong Li, and Ya-Feng Zhang
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Geology ,QE1-996.5 - Abstract
The failure of locked segment-type slopes is often affected by rainfall, earthquake, and other external loads. Rainfall scours the slope and weakens the mechanical properties of rock-soil mass. At the same time, rainfall infiltrates into cracks of slope rock mass. Under the action of in situ stress, hydraulic fracturing leads to the development and expansion of rock cracks, which increases the risk of slope instability. Under seismic force, the slope will be subjected to large horizontal inertial force, resulting in slope instability. In this paper, a self-developed loading device was used to simulate the external loads such as rainfall and earthquake, and the model tests are carried out to study the evolution mechanism of landslide with retaining wall locked segment. Three-dimensional laser scanner, microearth pressure sensors, and high-definition camera are applied for the high-precision monitoring of slope shape, deformation, and stress. Test results show that the retaining wall locked segment has an important control effect on landslide stability. The characteristics of deformation evolution and stress response of landslide with retaining wall locked segment are analyzed and studied by changing the slope shape, earth pressure, and the displacement cloud map. The evolutionary process of landslide with retaining wall locked segment is summarized. Experimental results reveal that as the landslide with retaining wall locked segment is at failure, the upper part of the landslide thrusts and slides and the retaining wall produces a locking effect; the middle part extrudes and uplifts, which is accompanied with shallow sliding; and compression-shear fracture of the locked segment leads to the landslide failure.
- Published
- 2022
- Full Text
- View/download PDF
3. Nogo-A expression dynamically varies after spinal cord injury
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Jian-wei Wang, Jun-feng Yang, Yong Ma, Zhen Hua, Yang Guo, Xiao-lin Gu, and Ya-feng Zhang
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Alzheimer′s disease ,amyloid-β ,astrocytes ,Ca 2+ ,calcilytic ,calcium-sensing receptor ,nitromemantine ,NPS 2143 ,α7-nicotinic acetylcholine receptor ,nerve regeneration ,spinal cord injury ,surgical decompression ,tumor necrosis factor α ,cell apoptosis ,neurological function ,neural regeneration ,contusion ,Nogo-A ,axon growth ,immunohistochemistry ,fluorescent quantitative PCR ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
The mechanism involved in neural regeneration after spinal cord injury is unclear. The myelin-derived protein Nogo-A, which is specific to the central nervous system, has been identified to negatively affect the cytoskeleton and growth program of axotomized neurons. Studies have shown that Nogo-A exerts immediate and chronic inhibitory effects on neurite outgrowth. In vivo, inhibitors of Nogo-A have been shown to lead to a marked enhancement of regenerative axon extension. We established a spinal cord injury model in rats using a free-falling weight drop device to subsequently investigate Nogo-A expression. Nogo-A mRNA and protein expression and immunoreactivity were detected in spinal cord tissue using real-time quantitative PCR, immunohistochemistry and western blot analysis. At 24 hours after spinal cord injury, Nogo-A protein and mRNA expression was low in the injured group compared with control and sham-operated groups. The levels then continued to drop further and were at their lowest at 3 days, rapidly rose to a peak after 7 days, and then gradually declined again after 14 days. These changes were observed at both the mRNA and protein level. The transient decrease observed early after injury followed by high levels for a few days indicates Nogo-A expression is time dependent. This may contribute to the lack of regeneration in the central nervous system after spinal cord injury. The dynamic variation of Nogo-A should be taken into account in the treatment of spinal cord injury.
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- 2015
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4. The requirement of WHIRLY1 for embryogenesis is dependent on genetic background in maize.
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Ya-Feng Zhang, Ming-Ming Hou, and Bao-Cai Tan
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Medicine ,Science - Abstract
Plastid gene expression is essential to embryogenesis in higher plants, but the underlying mechanism is obscure. Through molecular characterization of an embryo defective 16 (emb16) locus, here we report that the requirement of plastid translation for embryogenesis is dependent on the genetic background in maize (Zea mays). The emb16 mutation arrests embryogenesis at transition stage and allows the endosperm to develop largely normally. Molecular cloning reveals that Emb16 encodes WHIRLY1 (WHY1), a DNA/RNA binding protein that is required for genome stability and ribosome formation in plastids. Interestingly, the previous why1 mutant alleles (why1-1 and why1-2) do not affect embryogenesis, only conditions albino seedlings. The emb16 allele of why1 mutation is in the W22 genetic background. Crosses between emb16 and why1-1 heterozygotes resulted in both defective embryos and albino seedlings in the F1 progeny. Introgression of the emb16 allele from W22 into A188, B73, Mo17, Oh51a and the why1-1 genetic backgrounds yielded both defective embryos and albino seedlings. Similar results were obtained with two other emb mutants (emb12 and emb14) that are impaired in plastid protein translation process. These results indicate that the requirement of plastid translation for embryogenesis is dependent on genetic backgrounds, implying a mechanism of embryo lethality suppression in maize.
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- 2013
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5. Will renewal fee reduction introduce low-quality patents? Evidence from patents endorsed LOR in the UK
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Li-Ming Li, Chun-Yu Zhang, and Ya-Feng Zhang
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Management of Technology and Innovation ,General Economics, Econometrics and Finance - Published
- 2023
6. The effects of micro-aeration on semi-continued anaerobic digestion of corn straw with increasing organic loading rates
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Rong Zhu, Ya-feng Zhang, Hua Zou, Rong-Bo Guo, and Shan-Fei Fu
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Renewable Energy, Sustainability and the Environment - Published
- 2022
7. Mitochondrion-encoded circular RNAs are widespread and translatable in plants
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Xun Liao, Xiao-Jie Li, Guan-Tao Zheng, Feng-Rui Chang, Lin Fang, Hang Yu, Jun Huang, and Ya-Feng Zhang
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Physiology ,fungi ,Arabidopsis ,food and beverages ,Oryza ,RNA, Circular ,Plant Science ,Plants ,Zea mays ,Mitochondria ,Solanum lycopersicum ,Gene Expression Regulation, Plant ,RNA, Plant ,Genetics ,Vitis ,Research Articles - Abstract
Nucleus-encoded circular RNAs (ncircRNAs) have been widely detected in eukaryotes, and most circRNA identification algorithms are designed to identify them. However, using these algorithms, few mitochondrion-encoded circRNAs (mcircRNAs) have been identified in plants, and the role of plant mcircRNAs has not yet been addressed. Here, we developed a circRNA identification algorithm, mitochondrion-encoded circRNA identifier, based on common features of plant mitochondrial genomes. We identified 7,524, 9,819, 1,699, 1,821, 1,809, and 5,133 mcircRNAs in maize (Zea mays), Arabidopsis (Arabidopsis thaliana), rice (Oryza sativa), tomato (Solanum lycopersicum), cucumber (Cucumis sativus), and grape (Vitis vinifera), respectively. These mcircRNAs were experimentally validated. Plant mcircRNAs had distinct characteristics from ncircRNAs, and they were more likely to be derived from RNA degradation but not intron backsplicing. Alternative circularization was prevalent in plant mitochondria, and most parental genomic regions hosted multiple mcircRNA isoforms, which have homogenous 5′ termini but heterogeneous 3′ ends. By analysis of mitopolysome and mitoribosome profiling data, 1,463 mcircRNAs bound to ribosomes were detected in maize and Arabidopsis. Further analysis of mass spectrometry-based proteomics data identified 358 mcircRNA-derived polypeptides. Overall, we developed a computational pipeline that efficiently identifies plant mcircRNAs, and we demonstrated mcircRNAs are widespread and translated in plants.
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- 2022
8. How do rainfall intensity and raindrop size determine stemflow production? Quantitative evaluation from field rainfall simulation experiments
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Rui Hu, Yan-xia Pan, Ya-feng Zhang, and Xin-ping Wang
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Stemflow ,Field (physics) ,Production (economics) ,Environmental science ,Atmospheric sciences ,Intensity (heat transfer) ,Rainfall simulation ,Water Science and Technology - Abstract
The effects of rainfall intensity on stemflow production as described in the literature are quite inconsistent (increase, decrease, or no clear relationship) due to complex interactions between rai...
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- 2021
9. Isotope variations and interrelationship characteristics of different water reservoirs during non-rainfall events in revegetation desert area, northwest China
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Yan-xia Pan, Ya-feng Zhang, Xin-ping Wang, Yang Zhao, Zhi-shan Zhang, Xu-dong Wu, and Dong-qing Wang
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Water Science and Technology - Published
- 2023
10. Roxadustat for dialysis patients with erythropoietin hypo-responsiveness: a single-center, prospective investigation
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Xiao-Xia Chen, Ya-Feng Zhang, Hong-Bo Yuan, Yue Zhou, and Ji-Zhuang Lou
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Adult ,Male ,medicine.medical_specialty ,Anemia ,Glycine ,Renal function ,030204 cardiovascular system & hematology ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Internal Medicine ,medicine ,Humans ,Prospective Studies ,030212 general & internal medicine ,Renal Insufficiency, Chronic ,Adverse effect ,Erythropoietin ,Aged ,chemistry.chemical_classification ,Transferrin saturation ,business.industry ,Middle Aged ,Isoquinolines ,medicine.disease ,chemistry ,Transferrin ,Emergency Medicine ,Erythropoiesis ,Female ,Hemoglobin ,business ,Dialysis ,medicine.drug - Abstract
Dialysis patients with erythropoietin hypo-responsiveness suffered from refractory anemia. Roxadustat reversibly binds and inhibits hypoxia-inducible factor-prolyl hydroxylase (HIF-PHD), resulting in increased endogenous EPO which stimulates erythropoiesis, theoretically has an advantage over exogenous EPO in anti-anemia therapy. From September 2019 to October 2020, 32 dialysis patients with hypo-responsiveness to erythropoietin were evaluated. During the 24-week follow-up period, all patients were taken off erythropoietin and switched to roxadustat. Dosage adjustments were administrated according to the fluctuation of hemoglobin level during the treatment. Parameters about anemia, iron metabolism and biochemical indexes were collected, and adverse events were recorded. A total of 31 patients completed the clinical observation, with varying degrees of malnutrition-inflammation. Post treatment, the levels of transferrin and total iron-binding capacity were increased, while that of transferrin saturation and cholesterol decreased. 15 cases (accounting for 48.39%, designated as fulfilled group) met the target level of hemoglobin, while 16 cases (51.61%, non-fulfilled group) did not. The baseline conditions of the above two groups were compared. The levels of hypersensitive C-reactive protein, interleukin-6 and serum ferritin in the non-fulfilled group were higher than those in the fulfilled group, and the levels of residual renal function, serum albumin, iron, transferrin and total iron-binding capacity were lower than those in the fulfilled group. Linear regression analysis showed that increase of HsCRP had a negative effect on the improvement of Hb. One case of adverse reaction grade 3 and four cases of grade 2 occurred throughout the study, yet all were relieved after therapy. Significant anti-anemia effects could be achieved in most patients with erythropoietin hypo-responsiveness after treatment with roxadustat, accompanied by relatively mild and rare adverse reactions. The malnutrition-inflammation states of patients may interfere with the anti-anemia effect of roxadustat, and iron utilization is more important than iron storage in anemia improvement.
- Published
- 2021
11. Global quantitative synthesis of effects of biotic and abiotic factors on stemflow production in woody ecosystems
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Ning Chen, Yan-xia Pan, Rui Hu, Xin-ping Wang, and Ya-feng Zhang
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Abiotic component ,Global and Planetary Change ,Stemflow ,Ecology ,Climatic variables ,Environmental science ,Production (economics) ,Ecosystem ,Ecology, Evolution, Behavior and Systematics - Published
- 2021
12. Cultural and Creative Industries and Copyright at the Regional Level: The Cases of Shenzhen and Hangzhou in China
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Ya-Feng Zhang
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Renewable Energy, Sustainability and the Environment ,Geography, Planning and Development ,ComputingMilieux_LEGALASPECTSOFCOMPUTING ,cultural creative industries (CCIs) ,copyright ,creative economy ,China ,Management, Monitoring, Policy and Law - Abstract
Cultural creative industries (CCIs) have become an important driver in motivating the modern economy around the world, and the sustainable development of CCI is calling for a proper profit mechanism. Using China as the research context, this article investigates how copyright is used in the development of CCIs. The cities of Shenzhen and Hangzhou are selected as cases, and I identify 98 representative CCI enterprises from Shenzhen and 127 representative CCI enterprises from Hangzhou to conduct the analysis. It is found that the development of CCIs in different cities shows different models with regional characteristics, and shares some characteristics in common; most CCI enterprises have experience with copyright registration; copyright is highly correlated with other types of intellectual property (e.g., patent, trademark), and there is an obvious integration of copyright and technology; judicial lawsuits have become a major tool for enterprises to use copyright to protect their benefits, with plaintiffs winning the majority of the lawsuits. This research has both significant theoretical and practical implications, and contributes to theory about the use of copyright in the development of CCI at a regional level.
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- 2022
- Full Text
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13. Comparison of ultrasound irradiation on polymeric coloration of flavan-3-ols bridged by acetaldehyde and glyoxylic acid in model wine solution
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Zhen-Dan Xue, Qing-An Zhang, Ya-Feng Zhang, Er-Chun Li, and Xiao Sun
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Flavonoids ,Polymers ,Glyoxylates ,Polyphenols ,Wine ,Acetaldehyde ,General Medicine ,Chromatography, High Pressure Liquid ,Food Science ,Analytical Chemistry - Abstract
The influence and its mechanism of ultrasound on acetaldehyde/glyoxylic acid competing bridged the polymerization coloration of flavan-3-ols in model wine solution were investigated by high-performance liquid chromatography-mass spectrometry (HPLC-MS) and kinetics and thermodynamic model. The results indicate that ultrasound could significantly accelerate the polymerization coloration and further modify wine color. In addition, the polymerization reaction conformed first-order reaction model, and the reaction rate constant (k) values were markedly increased by ultrasound, accelerating the coloration reaction, especially in the model wine containing glyoxylic acid. Besides, the polymerization processing was non-spontaneous and endothermic according to the thermodynamic analysis. In conclusion, ultrasound was indeed conducive to accelerate glyoxylic acid/acetaldehyde-bridged the polymerization of flavan-3-ols and further effect the wine color, which could provide a theoretical basis for the scientific analysis of the mechanism of ultrasound modifying wine color.
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- 2023
14. The effect of different biocrusts on soil hydraulic properties in the Tengger Desert, China
- Author
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Wei Shi, Yan-xia Pan, Ya-feng Zhang, Rui Hu, and Xin-ping Wang
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Soil Science - Published
- 2023
15. The Effect of Biocrusts’ Succession Stages on Soil Hydraulic Properties in the Tengger Desert, China
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Wei Shi, Yanxia Pan, Ya-feng Zhang, Rui Hu, and Xin-ping Wang
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2022
16. Effect of changes of gut microbiota in constipation on lipid metabolism
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Cui-Ping Xu, Ya-Feng Zhang, and Yu-Jie Xu
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Constipation ,biology ,medicine ,Physiology ,Lipid metabolism ,medicine.symptom ,Gut flora ,biology.organism_classification - Published
- 2020
17. Material and Structure Performance of RPC Pavements for Steel Bridge Decks
- Author
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Ya-feng Zhang and Guo-yun Zhao
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Waterproofing ,Materials science ,business.industry ,Rut ,Stiffness ,Bending ,Structural engineering ,Strength of materials ,Asphalt concrete ,Cracking ,Deflection (engineering) ,medicine ,medicine.symptom ,business - Abstract
To solve the fatigue cracking problem in orthotropic steel decks (OSD) and to prevent the early damage of bridge pavements resulting from the low stiffness of the bridge deck system, epoxy-resin-perfused concrete (RPC) pavements were developed for improving the modulus and road performance of paving materials. The mechanical and road performance of RPC and the bonding performance of the waterproofing adhesive layer were studied via laboratory experiments. The mechanical property of RPC pavements and their protective function on OSD were analyzed by using a finite element model. Composite beam fatigue life and acceleration loading tests were performed on a scaled model to verify the performance of these pavements. Results show that RPC has excellent high-and low-temperature stability and water stability that can meet the requirements and has a relatively long fatigue life. The bonding strength of RPC pavements and steel plate is better than that of epoxy asphalt concrete and Gussasphalt concrete pavements. RPC pavements have a relatively low tensile stress on the surface and a relatively high shear stress below the surface, but these stresses are far lower than the material strength. When paved with RPC, the stress in the fatigue details of OSD is reduced by more than 20%. The maximum relative deflection between ribs, the minimum curvature radius, and the relative deflection to span ratio of RPC are also favorable, thereby providing additional protection for the bridge deck system. The fatigue life tested with a five-point bending composite beam is more than 1 million times, which meets the requirements. In the acceleration loading test, RPC pavements do not show any rut, whereas the OSD shows no cracking when loaded for 12 thousands times. The engineering application results demonstrate the feasibility of using RPC pavements and show that these pavements and OSD endure no damage.
- Published
- 2019
18. Alteration in isotopic composition of gross rainfall as it is being partitioned into throughfall and stemflow by xerophytic shrub canopies within water-limited arid desert ecosystems
- Author
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Rui Hu, Ya-feng Zhang, Yan-xia Pan, and Xin-ping Wang
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Canopy ,China ,Biogeochemical cycle ,Environmental Engineering ,Stemflow ,010504 meteorology & atmospheric sciences ,Rain ,ved/biology.organism_classification_rank.species ,Oxygen Isotopes ,010501 environmental sciences ,01 natural sciences ,Shrub ,Forest ecology ,Water Movements ,Environmental Chemistry ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Hydrology ,ved/biology ,Water ,Vegetation ,Deuterium ,Throughfall ,Pollution ,Arid ,Caragana ,Environmental science - Abstract
Isotopic composition of gross rainfall has been extensively used as a conservative tracer to track water movement and other hydrological processes in vegetated ecosystems. Recent studies from forest ecosystems, however, demonstrated that vegetation canopies can alter the isotopic composition of rainwater during rainfall partitioning into throughfall and stemflow, likely leading to errors and biases in aforementioned studies. No known studies, to date, had investigated this topic in shrub-dominated arid and semi-arid ecosystems where water is typically the driving factor in ecological, hydrological and biogeochemical processes. In this study, event-based gross rainfall, the throughfall and stemflow induced by shrubs of Caragana korshinskii were measured and samples were collected within a water-limited arid desert ecosystem of northern China, and their water stable isotopes (18O and 2H) were also analyzed in the laboratory. We mainly aimed to investigate whether there is an isotopic enrichment or depletion in stemflow and throughfall in comparison to gross rainfall, and to evaluate the possible underlying mechanisms. Our results indicated an enrichment of both isotopes in stemflow, while a general more depletion in throughfall than in gross rainfall, which is presumably affected by a combinative effects of canopy evaporation, isotopic exchange, and selective canopy storage. Deuterium excess of stemflow were found to be significantly higher (P
- Published
- 2019
19. Spatiotemporal variation of soil water potential and its significance to water balance for a desert shrub area
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Xin-ping Wang, Ronny Berndtsson, Yan-xia Pan, Rui Hu, Ya-feng Zhang, and Yan Li
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Soil Science ,Agronomy and Crop Science ,Earth-Surface Processes - Published
- 2022
20. Do specialized intellectual property courts show a pro-patent propensity? Evidence from China
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Ya-Feng Zhang, Li-Ming Li, and Ke Xu
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Economics and Econometrics ,Law ,Finance - Published
- 2022
21. Fine root production, turnover of <scp> Reaumuria songarica </scp> and soil carbon and nitrogen in Alxa steppe desert of <scp>NW</scp> China
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Yan‐xia Jin, Ma Xiongzhong, Ya-feng Zhang, and Xin-ping Wang
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geography ,geography.geographical_feature_category ,Ecology ,Reaumuria songarica ,Steppe ,ved/biology ,ved/biology.organism_classification_rank.species ,chemistry.chemical_element ,Soil carbon ,Nitrogen ,Shrub ,chemistry ,Agronomy ,Environmental science ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Published
- 2021
22. UV-activated persulfate oxidation of sulfamethoxypyridazine: Kinetics, degradation pathways and impact on DBP formation during subsequent chlorination
- Author
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Naiyun Gao, Ya-feng Zhang, Yu-qiong Gao, Wenhai Chu, Daqiang Yin, and Jia Zhang
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chemistry.chemical_classification ,Chloroform ,Chemistry ,General Chemical Engineering ,Advanced oxidation process ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Persulfate ,01 natural sciences ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,Chemical kinetics ,chemistry.chemical_compound ,Aniline ,Reaction rate constant ,Environmental Chemistry ,Humic acid ,Hydroxyl radical ,0210 nano-technology ,Nuclear chemistry - Abstract
The kinetics and mechanisms of the degradation of sulfamethoxypyridazine (SMP) by an ultraviolet-activated persulfate (UV/PS) advanced oxidation process (AOP) and the formation of disinfection byproducts (DBPs) during subsequent chlorination were investigated in this study. The UV/PS process can significantly remove SMP through pseudo-first-order reaction kinetics. In a competitive kinetic experiment, the second-order rate constant of SMP with sulfate radical was determined to be 2.73 × 1010 M−1 s−1, while that with hydroxyl radical was 2.22 × 1010 M−1 s−1. Six major transformation products in SMP degradation were recognized by LC/MS/MS analysis. It was assumed that the degradation pathway of SMP involves the hydroxylation of the aromatic ring, cleavage of the sulfonamide bond, oxidation of the aniline moiety and elimination of SO2. The impacts of persulfate dose, pH, anions (HCO3–, SO42−, and Br−) and humic acid (HA) concentration on SMP degradation efficiency and DBP formation during subsequent chlorination were also examined. SMP degradation was accelerated with increasing persulfate dose, HCO3– and Br- concentration as well as decreasing pH and HA concentration. However, the amount of chloroform (CF) formed was reduced under a higher persulfate dosage and lower pH. In contrast, the amount of dichloroacetonitrile (DCAN) formed was enhanced under a higher persulfate dose and lower pH. Adding HA also increased the formation of both CF and DCAN. While, both HCO3– and SO42– had little effects on the formation of CF and DCAN. The presence of Br– had no significant effects on the bromine incorporation factors (BIFs) of trihalomethanes (THMs) and dihaloacetonitriles (DHANs). Raw water experiments showed that the UV/PS process could destroy SMP in natural water as well as control the formation of DBPs.
- Published
- 2019
23. Sulfate radical-based technology for the removal of 2-methylisoborneol and 2-methylisoborneol-producing algae in drinking water sources
- Author
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Ya-nan Zhang, Wenjun Zhang, Ya-feng Zhang, Lei Li, Stephan Küppers, Lei Jin, Naiyun Gao, and Dong Zhang
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inorganic chemicals ,Pollutant ,General Chemical Engineering ,fungi ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Persulfate ,01 natural sciences ,digestive system diseases ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,chemistry.chemical_compound ,Potassium permanganate ,chemistry ,Sodium hypochlorite ,Environmental Chemistry ,Degradation (geology) ,Water treatment ,2-Methylisoborneol ,0210 nano-technology ,neoplasms ,Surface water ,Nuclear chemistry - Abstract
The most common odor substance found in surface water is 2-methylisoborneol (2-MIB), and this substance cannot be effectively removed by conventional water treatment processes. Persulfate (S2O82−, PS)-based oxidation has recently received wide attention due to its promising ability to remove refractory pollutants. In this research, the degradation of 2-MIB by PS activated with iron (II) (PS-Fe2+) or heat (PS-Heat) was investigated. Kinetic analysis indicated that 2-MIB degradation in both of the systems (PS-Heat and PS-Fe2+) followed a pseudo-first-order reaction. For the PS-Heat system, a high temperature, a high PS initial concentration and weakly acidic conditions benefit the degradation of 2-MIB. Coexisting anions inhibit 2-MIB removal in the following order: CO32− > HCO3− > Cl−. For the PS-Fe2+ system, the optimum molar ratio of PS to Fe2+ ([PS]: [Fe2+]) was 1:1. The 2-MIB degradation rate increased under acidic conditions and with the addition of citrate; however, the rate decreased with an excess Fe2+ dosage. In addition, this study was the first to examine the behavior pattern of algal photosynthesis activity as well as the total and extracellular 2-MIB of Pseudoanabaena sp. (a typical 2-MIB-producing cyanobacterium) in the PS-Fe2+ system. Moreover, a comparison study of the removal of 2-MIB in actual algae-containing water under the oxidation of PS-Fe2+, potassium permanganate (KMnO4), and sodium hypochlorite (NaClO) was firstly carried out. The results provide useful theoretical and engineering information for treating algae-loaded water.
- Published
- 2019
24. Acute Kidney Injury in Patients with Acute Coronary Syndrome after Percutaneous Coronary Intervention: Pathophysiologies, Risk Factors, and Preventive Measures
- Author
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Yue Zhou, Da-Dong Liu, Ji-Zhuang Lou, and Ya-Feng Zhang
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medicine.medical_specialty ,Acute coronary syndrome ,business.industry ,medicine.medical_treatment ,Acute kidney injury ,Percutaneous coronary intervention ,Context (language use) ,Perioperative ,Acute Kidney Injury ,urologic and male genital diseases ,medicine.disease ,Nephropathy ,Percutaneous Coronary Intervention ,Embolism ,Risk Factors ,Conventional PCI ,medicine ,Humans ,Pharmacology (medical) ,Acute Coronary Syndrome ,Cardiology and Cardiovascular Medicine ,Intensive care medicine ,business - Abstract
Background: Percutaneous coronary intervention (PCI) has been an effective treatment for acute coronary syndrome (ACS) patients. Acute kidney injury (AKI) is one of the common complications after PCI, which seriously affects the living quality and survival time of patients. The approach followed for the patient with AKI after PCI depends on the clinical context and may vary by resource availability. Summary: This review focuses on the pathophysiologies, influencing factors, and preventive measures of AKI in patients with ACS after PCI. The knowledge may better serve the patients and improve their outcomes. Key Messages: Many studies have been carried out for the definition and standard of AKI in the past few years. Etiologies of AKI after PCI included renal damage of contrast medium and atherosclerotic embolism, cardiac insufficiency and surgical factors on renal function. Basic conditions, treatment modalities, and perioperative changes are major risk factors of AKI. Studies have reported that the prevention of contrast-induced nephropathy, modulating the volume overload, some pharmaceuticals and blood purification treatment are helpful to prevent the occurrence of AKI.
- Published
- 2020
25. Down-regulated microRNA-199a-3p enhances osteogenic differentiation of bone marrow mesenchymal stem cells by targeting Kdm3a in ovariectomized rats
- Author
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Jia-Cheng Xu, Ya-Feng Zhang, Jie Sun, Jian-Cheng Wu, and Zhen-Yu Zhou
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Ovariectomy ,Kruppel-Like Transcription Factors ,Down-Regulation ,Biochemistry ,Bone and Bones ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,Skeletal disorder ,Antigens, CD ,Genes, Reporter ,Osteogenesis ,microRNA ,medicine ,Animals ,Humans ,CD90 ,Gene Regulatory Networks ,Molecular Biology ,Osteoporosis, Postmenopausal ,030304 developmental biology ,Histone Demethylases ,Mitogen-Activated Protein Kinase 1 ,0303 health sciences ,biology ,Mesenchymal stem cell ,CD44 ,Mesenchymal Stem Cells ,Cell Biology ,Azepines ,Rats ,Disease Models, Animal ,MicroRNAs ,medicine.anatomical_structure ,Gene Expression Regulation ,030220 oncology & carcinogenesis ,Gene Knockdown Techniques ,KLF2 ,biology.protein ,Ovariectomized rat ,Cancer research ,Quinazolines ,Osteoporosis ,Female ,Bone marrow - Abstract
Osteoporosis is a prevalent systemic skeletal disorder entailing bone fragility and increased fracture risk, often emerging in post-menopausal life. Emerging evidence implicates the dysregulation of microRNAs (miRNAs or miRs) in the progression of osteoporosis. This study investigated the effect of miR-199a-3p on osteoporosis and its underlying mechanism. We first examplished an ovariectomized (OVX)-induced rat osteoporosis model, and then isolated mesenchymal stem cells (MSCs) from bone marrow of the model rats. The overexpression and knock down of miR-199a-3p were conducted in OVX rats and MSCs to verify the role of miR-199a-3p on MSC differentiation. Calcium nodules were measured using alizarin red S (ARS) staining. RT-qPCR and Western blot assay were performed to measure the expression of miR-199a-3p, Kdm3a and osteogenic differentiation-related markers in rat tissues and cells. The correlation between miR-199a-3p and Kdm3a was confirmed using dual-luciferase reporter assay. The enrichment of Kdm3a at the Erk2 and Klf2 promoter was assessed using chromatin immunoprecipitation (ChIP) assay. Isolated MSCs were positive for CD29, CD44, CD90, and CD45, suggesting successful isolation of MSCs. There was increased expression of miR-199a-3p and inhibited osteogenic differentiation in OVX rats. Kdm3a was negatively targeted by miR-199a-3p. Our results also demonstrated that Kdm3a elevated the expression of Erk2 and Erk2 by promoting Erk2 and Klf2 demethylation, which further contributed to osteogenic differentiation. Overall, our results revealed a regulatory network of miR-199a-3p in osteogenic differentiation, highlighting miR-199a-3p as a potential target for therapeutic interventions in osteoporosis.
- Published
- 2020
26. Clinical outcomes of Ti-Ni shape-memory patella concentrator combined with cannulated compression screws in the treatment of C2 and C3 patella fracture: a retrospective study of 54 cases
- Author
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Jie Sun, Ran Tao, Chen Yao, Zhen-Yu Zhou, Ya-Feng Zhang, Fan Liu, and Jian-Cheng Wu
- Subjects
musculoskeletal diseases ,Comminuted patella fracture ,medicine.medical_specialty ,lcsh:Diseases of the musculoskeletal system ,medicine.medical_treatment ,Bone Screws ,Fixation technique ,Bone healing ,03 medical and health sciences ,Fracture Fixation, Internal ,Fractures, Bone ,0302 clinical medicine ,Rheumatology ,Nickel ,Clinical outcomes ,Activities of Daily Living ,medicine ,Internal fixation ,Humans ,Shape-memory patella concentrator ,Orthopedics and Sports Medicine ,Reduction (orthopedic surgery) ,Fractures, Comminuted ,Fixation (histology) ,Retrospective Studies ,030203 arthritis & rheumatology ,Titanium ,030222 orthopedics ,business.industry ,Patella ,medicine.disease ,musculoskeletal system ,Surgery ,Treatment Outcome ,Orthopedic surgery ,Patella fracture ,lcsh:RC925-935 ,Range of motion ,business ,Research Article - Abstract
Background Ti-Ni shape-memory patella concentrator (TNSMPC) has been designed as an alternative approach for fixation of patella fracture, which has some advantages like higher hardness, higher tenacity, better wearing resistance, excellent corrosion resistance and desired histocompatibility. The present study was to investigate the efficiency of TNSMPC combined with cannulated compression screws in the treatment of comminuted patella fractures. Methods Between January 2014 and December 2017, 54 patients of C2 and C3 patella fractures underwent open reduction and internal fixation with TNSMPC combined with cannulated compression screws. All the patients got standard postoperative rehabilitation programs and were regularly followed up for at least 12 months after the operation. X-rays, knee functions and life quality were evaluated during the follow-up. Results All the patients achieved bone healing and recovery of knee function with low incidence of complications according to outcomes of X-rays and questionnaires. The average operation time and blood loss during surgery were 77.5 ± 25.12 min and 24.25 ± 4.70 ml respectively. The Knee Outcome Survey Activities of Daily Living Scale, the range of motion and the 36-item short-form heath survey after the operation were all improved. According to the Bostman’s criteria, the excellent to good rate was 92.6%. Conclusion TNSMPC combined with cannulated compression screws is an effective internal fixation method for C2 and C3 patella fracture with excellent clinical outcomes. In addition, the operation does not increase extra technique difficulty or tissue damage relatively, which is worth promotion.
- Published
- 2020
27. Evapotranspiration of xerophytic shrub Salsola passerina and Reaumuria soongorica in an arid desert ecosystem of NW China
- Author
-
Hao-jie Xu, Yan-xia Pan, Ya-feng Zhang, Rui Hu, Jin Yanxia, Xin-ping Wang, and Wei Shi
- Subjects
010504 meteorology & atmospheric sciences ,Salsola passerina ,Ecology ,ved/biology ,0208 environmental biotechnology ,ved/biology.organism_classification_rank.species ,02 engineering and technology ,01 natural sciences ,Shrub ,Arid ,020801 environmental engineering ,Evapotranspiration ,Lysimeter ,Environmental science ,Ecosystem ,0105 earth and related environmental sciences ,Water Science and Technology ,Woody plant - Abstract
Understanding the actual evapotranspiration (ET) variation of the sparsely distributed xerophytic shrubs is crucial to accurately upscale community ET to ecosystem scale. Here we quantified the actual ET of two dominant xerophytic shrubs of the Tengger Desert in northwestern China, i.e. Salsola passerina and Reaumuria soongorica, by using four large weighing lysimeters. The results showed that with the increase in precipitation from 140 to 171 mm in the year 2015/2016, the daily mean evaporation (E) of the bare area, and ET of the single shrub communities of S. passerina, R. soongorica, and the associated shrub community (S. passerina + R. soongorica) increased 50, 60, 44, and 47%, respectively; correspondingly, the total E and ET increased 49, 61, 44, and 47%, respectively. The variation of soil moisture within 0–40 cm depth plays a vital role in regulating the E and ET. The new shoot length, as one of important parameters of the xerophytic shrub, was significantly exponentially related to the cumulative ET. From the long- and short-term perspective, event-based precipitation and wind speed are the dominant driving factors behind changes in E and ET, respectively. Relative humidity is the main influencing factor for E and ET after a large rainfall event within 8 days.
- Published
- 2018
28. The effect of biological soil crusts on soil moisture dynamics under different rainfall conditions in the Tengger Desert, China
- Author
-
Yan-xia Pan, Rui Hu, Xin-ping Wang, Ya-feng Zhang, Wei Shi, and Jin Yanxia
- Subjects
Hydrology ,010504 meteorology & atmospheric sciences ,040103 agronomy & agriculture ,Desert (particle physics) ,0401 agriculture, forestry, and fisheries ,Environmental science ,04 agricultural and veterinary sciences ,China ,01 natural sciences ,Water content ,0105 earth and related environmental sciences ,Water Science and Technology - Published
- 2018
29. Meteorological influences on process-based spatial-temporal pattern of throughfall of a xerophytic shrub in arid lands of northern China
- Author
-
Ya-feng Zhang, Rui Hu, Xin-ping Wang, and Yan-xia Pan
- Subjects
Canopy ,Environmental Engineering ,ved/biology ,0208 environmental biotechnology ,ved/biology.organism_classification_rank.species ,Growing season ,Soil science ,02 engineering and technology ,Atmospheric sciences ,Throughfall ,Pollution ,Shrub ,Arid ,020801 environmental engineering ,Principal component analysis ,Environmental Chemistry ,Environmental science ,Ecosystem ,Spatial variability ,Waste Management and Disposal - Abstract
Numerous field experiments had demonstrated great spatial variability and temporal stability of throughfall under tree canopies within forested ecosystems. Nonetheless, no known studies have investigated the intrastorm spatial-temporal variability of throughfall beneath xerophytic shrub canopies within arid desert ecosystems where water is typically the principal limiting factor determining the structure and dynamics of ecosystems. Here we investigated the spatial-temporal pattern of throughfall at intrastorm scale, and systematically examined the effects of meteorological variables on throughfall based on the principal components analysis (PCA) and a multiple regression model. Throughfall was monitored at 10-min intervals by placing tipping-bucket rain gauges at different radial directions beneath 3 shrubs of Caragana korshinskii during the growing season of 2016 within a water-limited arid desert ecosystem of northern China. We found the temporal heterogeneity of rainfall clearly affected the timing of throughfall beneath shrub canopies within discrete rainfall events. Throughfall also differed markedly among different radial directions beneath shrub canopies, which was found to be well associated with wind directions during rainfall events. PCA on meteorological variables indicated that three principal components accounted for 84.2% of the total variance, and we found that the second principal component (loaded strongly on rainfall amount and maximum 10-min rainfall intensity) was the dominant component controlling throughfall and its spatial variability after introducing three principal components into a multiple linear regression model. Our findings highlight the spatial-temporal variability of throughfall at the intrastorm scale, and are expected to be helpful for an improved process-based characterization and modelling of throughfall in vast arid desert ecosystems.
- Published
- 2018
30. Design of the Integral Field Measurement System of Dipole Magnets
- Author
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Wei Chen, Bin Qin, Ya Feng Zhang, Jun Yang, Ying Cai Xie, Tao Liu, and Hui Liang
- Subjects
Computer science ,System of measurement ,Mechanical engineering ,02 engineering and technology ,Superconducting magnet ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Magnetic flux ,Electronic, Optical and Magnetic Materials ,03 medical and health sciences ,Dipole ,0302 clinical medicine ,Data acquisition ,Beamline ,Electromagnetic coil ,030220 oncology & carcinogenesis ,Magnet ,Electrical and Electronic Engineering ,0210 nano-technology - Abstract
A new proton therapy facility (HUST-PTF) is under construction in the Huazhong University of Science and Technology. The integral field measurement system of dipole magnets was designed for the beamline of HUST-PTF. The design goal is to build a reliable, precise, and automatic measurement system, which is accurate enough to characterize the magnetic field quality of the dipole magnets. The system consists of long coils, precision motion stages, data acquisition, and control system. The design of the whole system and the measurement method is described in this paper. The design and fabrication of the long coil are also discussed, and the errors from the geometric frame of coil and electronic equipment are analyzed.
- Published
- 2018
31. Effects of Different Matrix on Interface and Compression Fracture Behavior of WC Particles Reinforced Iron Matrix Composites
- Author
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Feng Rui Chen, Ye Hua Jiang, Zu Lai Li, Quan Shan, Fei Zhang, and Ya Feng Zhang
- Subjects
Matrix (mathematics) ,020210 optoelectronics & photonics ,Materials science ,Mechanics of Materials ,Mechanical Engineering ,0202 electrical engineering, electronic engineering, information engineering ,Fracture (geology) ,General Materials Science ,02 engineering and technology ,Composite material ,Condensed Matter Physics ,Compression (physics) - Abstract
The WC particles reinforced iron matrix composites were prepared by utilizing energy ball milling powder mixed and vacuum powder sintering method in this paper. The effects of two kinds of matrix on the micro-structure, interface and fracture mechanism of the composites were studied emphatically, and it provided a theoretical guidance for the design and engineering application of particle reinforced metal matrix composites. The results show that: in the two kinds of matrix composites, WC particles and interface had different degree of melting, WC particles and the matrix were metallurgical combination; ferritic matrix composites had better compressibility than pearlite matrix composites (1089Mpa); the fracture mode of ferrite matrix composites was quasi-cleavage fracture and pearlite matrix composites was pure cleavage fracture; the compressive micro-cracks of the two matrix composites generated at the interface and expand at the interface to a broad macroscopic crack, which eventually the material fails.
- Published
- 2018
32. On the importance of stemflow to the woody plants in drylands: Individual vs. ecosystem scales
- Author
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Changming Zhao, Ya-feng Zhang, and Ning Chen
- Subjects
Stemflow ,Ecology ,Environmental science ,Ecosystem ,Water Science and Technology ,Woody plant - Abstract
Stemflow has long been recognized as an important ecohydrological process in drylands, and may influence dynamics of woody plants by altering rainfall redistribution. However, quantification of the effects of stemflow on woody plants dynamics remains largely unclear. It is also unknown whether the effects of stemflow are consistent for individual plants and ecosystems where woody plants grow. This study developed an ecohydrological model to explore how stemflow affected individual woody plants and ecosystems, and how the effects changed along a rainfall gradient (10–600 mm) in a dryland ecosystem. This study demonstrated the positive effects of stemflow on woody plants in both individual (by a degree of 16–48%) and ecosystem scales (by a degree of 8–45%). Stemflow started to promote woody plant growth in the individual scale even when annual rainfall was very low (
- Published
- 2021
33. Effects of ultrasound on the formation of oxidative pigments in a model red wine solution containing glutathione
- Author
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Bo-Yu Chen, Ya-Feng Zhang, Er-Chun Li, Bao-Shan Zhang, and Qing-An Zhang
- Subjects
Wine ,Chemistry ,Radical ,food and beverages ,Glutathione ,Photochemistry ,High-performance liquid chromatography ,Wine color ,law.invention ,chemistry.chemical_compound ,Pigment ,law ,visual_art ,visual_art.visual_art_medium ,Electron paramagnetic resonance ,Glyoxylic acid ,Food Science - Abstract
Xanthylium cations and its ethyl ester are important pigments derived from (+)-catechin and glyoxylic acid in wine. In this paper, ultrasound treatment was applied in model wine containing glutathione to study its effects on the formation of xanthylium cation pigments triggered by free radicals from the ultrasound cavitation. The changes in color parameters, concentration of pigment compounds and free radicals were investigated during wine storage by the means of ultraviolet visible (UV–vis) spectrophotometer, colorimeter, high performance liquid chromatography with mass spectrometry (HPLC-MS) and electron paramagnetic resonance (EPR), respectively. Results indicate that longer ultrasonic treatment in conjunction with glutathione can significantly enhance the formation of xanthylium cation pigments and accelerate the red wine color evolution, and no extra (+)-catechin was involved, which might be attributed to the stronger 1-hydroxyethyl radicals intensity induced by ultrasound irradiation. In summary, ultrasound treatment can accelerate the oxidative coloration of wine with GSH during ageing, which would contribute to well understand the changing mechanism of wine color properties modified by ultrasound.
- Published
- 2021
34. Stemflow volume per unit rainfall as a good variable to determine the relationship between stemflow amount and morphological metrics of shrubs
- Author
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Xin-ping Wang, Ya-feng Zhang, Yan-xia Pan, and Rui Hu
- Subjects
Hydrology ,Canopy ,Stemflow ,010504 meteorology & atmospheric sciences ,Ecology ,ved/biology ,0208 environmental biotechnology ,ved/biology.organism_classification_rank.species ,Growing season ,02 engineering and technology ,01 natural sciences ,Shrub ,020801 environmental engineering ,Basal area ,Volume (thermodynamics) ,Artemisia ordosica ,Linear regression ,Environmental science ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
In this study, we determined the relationship between stemflow amount and morphological metrics of plants. Previous studies on this issue generally neglected the influence of differential rainfall amounts on stemflow, which somehow bias the relationship between stemflow amount and morphological metrics. Here, field observation of stemflow in two xerophytic shrubs ( Caragana korshinskii and Artemisia ordosica ) of varying sizes were conducted during three growing seasons in 2011–2013 to evaluate this relationship by using a simple variable, i.e., stemflow volume per unit rainfall (SfVPR, mL mm −1 ). This stemflow index directly defines the influence of rainfall depth on the morphological metrics of plants, and it has the following advantages over the conventional stemflow coefficient that has been used to determine the influence of tree/shrub morphological metrics on the stemflow amount: (1) it avoids the bias caused by the influences of differential rainfall amount on stemflow yield and (2) it is suitable for use in hydrological models. Our results showed that SfVPR can well be used to determine the relationship between stemflow amount and shrub morphological metrics. Moreover, by using multiple regression model, we found that projected canopy area (or canopy volume, or basal area), plant area index, and stem diameter are the most influential factors for the stemflow amount of C. korshinskii, whereas no significant explanatory variables were found for that of A. ordosica .
- Published
- 2017
35. Differential intra-specific stemflow funnelling efficiencies of Caragana korshinskii within arid desert ecosystems
- Author
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Xin-ping Wang, Ya-feng Zhang, Rui Hu, and Yan-xia Pan
- Subjects
Hydrology ,Caragana korshinskii ,Stemflow ,010504 meteorology & atmospheric sciences ,Ecology ,ved/biology ,0208 environmental biotechnology ,ved/biology.organism_classification_rank.species ,Biogeochemistry ,02 engineering and technology ,01 natural sciences ,Arid ,Shrub ,020801 environmental engineering ,Hydrology (agriculture) ,Environmental science ,Ecosystem ,0105 earth and related environmental sciences ,Water Science and Technology ,Woody plant - Abstract
Stemflow is known as a highly localized point input of rainwater and solutes around tree/shrub bases where roots are concentrated, thus having considerable effects on hydrology and biogeochemistry of vegetated ecosystems. Stemflow shows a pronounced inter-specific variation due to morphological differences among species, while the intra-specific variation of stemflow has been poorly explored. We systematically examined the effects of shrub morphological metrics on intra-specific funnelling efficiencies by quantifying the stemflow of nine shrubs of Caragana korshinskii within a water-limited arid desert ecosystem of northern China. Stemflow volume was used to compare the absolute amount of stemflow generated by shrubs of varying size, and funnelling ratio was used to assess their funnelling efficiencies. Both rainfall depth and shrub morphological metrics significantly affected stemflow volume, while funnelling ratio was more associated with shrub morphology. Under the same rainfall condition, smaller shrubs produced lower volumes of stemflow, while gaining access to rainfall via higher funnelling ratio than larger shrubs. Our findings highlight a large variation in funnelling efficiency among individual shrubs within the same species, and in particular, smaller shrubs might profit more from sporadic small rainfall events than larger shrubs.
- Published
- 2017
36. Processing of a Novel Zn Alloy Micro-Tube for Biodegradable Vascular Stent Application
- Author
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Haibo Gong, Gongqi Qu, Ya-Feng Zhang, Chang Wang, Cui Yajun, Sen Yu, and Zhentao Yu
- Subjects
Materials science ,Polymers and Plastics ,Alloy ,chemistry.chemical_element ,02 engineering and technology ,Zinc ,engineering.material ,010402 general chemistry ,01 natural sciences ,Corrosion ,Ultimate tensile strength ,Materials Chemistry ,Ductility ,Biodegradable metal ,Mechanical Engineering ,Metallurgy ,Metals and Alloys ,Micro tube ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Vascular stent ,chemistry ,Mechanics of Materials ,Ceramics and Composites ,engineering ,0210 nano-technology - Abstract
In recent years, zinc based alloys as a new biodegradable metal material aroused intensive interests. However, the processing of Zn alloys micro-tubes (named slender-diameter and thin-walled tubes) is very difficult due to their HCP crystal structure and unfavorable mechanical properties. This study aimed to develop a novel technique to produce micro-tube of Zn alloy with good performance for biodegradable vascular stent application. In the present work, a processing method that combined drilling, cold rolling and optimized drawing was proposed to produce the novel Zn–5Mg–1Fe (wt%) alloy micro-tubes. The micro-tube with outer diameter of 2.5 mm and thickness of 130 µm was fabricated by this method and its dimension errors are within 10 µm. The micro-tube exhibits a fine and homogeneous microstructure, and the ultimate tensile strength and ductility are more than 220 MPa and 20% respectively. In addition, the micro-tube and stents of Zn alloy exhibit superior in vitro corrosion and expansion performance. It could be concluded that the novel Zn alloy micro-tube fabricated by above method might be a promising candidate material for biodegradable stent.
- Published
- 2016
37. The mechanism of soil nitrogen transformation under different biocrusts to warming and reduced precipitation: From microbial functional genes to enzyme activity
- Author
-
Jun-shan Xu, Yan-xia Pan, Xin-ping Wang, Rui Hu, Ya-feng Zhang, and Xue Su
- Subjects
Biogeochemical cycle ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Chemistry ,Nitrogen ,Mineralization (soil science) ,010501 environmental sciences ,01 natural sciences ,Pollution ,Soil ,Microbial population biology ,Agronomy ,Soil water ,Temperate climate ,Environmental Chemistry ,Nitrification ,Ecosystem ,Waste Management and Disposal ,Nitrogen cycle ,Genes, Microbial ,Soil Microbiology ,0105 earth and related environmental sciences - Abstract
Soil nitrogen (N) mineralization is a microbially-mediated biogeochemical process that is strongly influenced by changing climates. However, little information is available on the mechanisms behind the response of N mineralization to prolonged warming coupled with drought in soils covered by biocrusts. We used open top chambers to investigate the rate of soil N transformation (ammonification, nitrification and mineralization), enzyme activity and gene abundance in response to warming coupled with reduced precipitation over three years (2016-2018). Warming and drought significantly reduced the N transformation rate, extracellular enzyme activity, and gene abundance in moss-covered soil. For cyanobacteria-covered soil, however, it inhibited enzyme activity and increased the abundance of the nitrification-related genes and therefore nitrification rate. Our treatments had no obvious effects on N transformation and enzyme activity, but reduced gene abundance in bare soil. Biocrusts may facilitate N transformation while the degradation of moss crust caused by climate warming will dampen any regulating effect of biocrusts on the belowground microbial community. Furthermore, belowground microbial communities can mediate N transformation under ongoing warming and reduced precipitation by suppressing ammonification- and nitrification-related gene families, and by stimulating nitrification-related gene families involved in cyanobacteria-covered soil. This study provides a basis for identifying the functional genes involved in key processes in the N cycle in temperate desert ecosystems, and our results further highlight the importance of different biocrusts organisms in the N cycle in temperate deserts as Earth becomes hotter and drier.
- Published
- 2019
38. Throughfall and its spatial variability beneath xerophytic shrub canopies within water-limited arid desert ecosystems
- Author
-
Ya-feng Zhang, Yan-xia Pan, Rui Hu, and Xin-ping Wang
- Subjects
Biogeochemical cycle ,010504 meteorology & atmospheric sciences ,ved/biology ,Ecology ,0208 environmental biotechnology ,ved/biology.organism_classification_rank.species ,Biogeochemistry ,02 engineering and technology ,Throughfall ,01 natural sciences ,Shrub ,Arid ,020801 environmental engineering ,Environmental science ,Ecosystem ,Spatial variability ,0105 earth and related environmental sciences ,Water Science and Technology ,Woody plant - Abstract
Summary Throughfall is known to be a critical component of the hydrological and biogeochemical cycles of forested ecosystems with inherently temporal and spatial variability. Yet little is understood concerning the throughfall variability of shrubs and the associated controlling factors in arid desert ecosystems. Here we systematically investigated the variability of throughfall of two morphological distinct xerophytic shrubs (Caragana korshinskii and Artemisia ordosica) within a re-vegetated arid desert ecosystem, and evaluated the effects of shrub structure and rainfall characteristics on throughfall based on heavily gauged throughfall measurements at the event scale. We found that morphological differences were not sufficient to generate significant difference (P
- Published
- 2016
39. Comparison of diurnal dynamics in evaporation rate between bare soil and moss-crusted soil within a revegetated desert ecosystem of northwestern China
- Author
-
Yan-xia Pan, Ya-feng Zhang, Xin-ping Wang, and Rui Hu
- Subjects
Hydrology ,010504 meteorology & atmospheric sciences ,Diurnal temperature variation ,Evaporation ,Soil science ,04 agricultural and veterinary sciences ,01 natural sciences ,Leaching model ,Field capacity ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,General Earth and Planetary Sciences ,Revegetation ,Soil fertility ,Water content ,Geology ,0105 earth and related environmental sciences - Abstract
Effects of biological soil crusts (BSCs) on soil evaporation is quite controversial in literature, being either facilitative or inhibitive, and therein few studies have actually conducted direct evaporation measurements. Continuous field measurements of soil water evaporation were conducted on two microlysimeters, i.e., one with sand soil collected from bare sand dune area and the other with moss-crusted soil collected from an area that was revegetated in 1956, from field capacity to dry, at the southeastern edge of the Tengger Desert. We mainly aimed to quantify the diurnal variations of evaporation rate from two soils, and further comparatively discuss the effects of BSCs on soil evaporation after revegetation. Results showed that in clear days with high soil water content (Day 1 and 2), the diurnal variation of soil evaporation rate followed the typical convex upward parabolic curve, reaching its peak around mid-day. Diurnal evaporation rate and the accumulated evaporation amount of moss-crusted soil were lower (an average of 0.90 times) than that of sand soil in this stage. However, as soil water content decreased to a moderately low level (Day 3 and 4), the diurnal evaporation rate from moss-crusted soil was pronouncedly higher (an average of 3.91 times) than that of sand soil, prolonging the duration of this higher evaporation rate stage; it was slightly higher in the final stage (Day 5 and 6) when soil moisture was very low. We conclude that the effects of moss crusts on soil evaporation vary with different evaporation stages, which is closely related to soil water content, and the variation and transition of evaporation rate between bare soil and moss-crusted soil are expected to be predicted by soil water content.
- Published
- 2016
40. Insight into the influence of sand-stabilizing shrubs on soil enzyme activity in a temperate desert
- Author
-
Jin Yanxia, Ning Chen, Wei Shi, Ya-feng Zhang, Rui Hu, and Xin-ping Wang
- Subjects
010504 meteorology & atmospheric sciences ,ved/biology ,Ecology ,ved/biology.organism_classification_rank.species ,food and beverages ,Growing season ,04 agricultural and veterinary sciences ,Biology ,complex mixtures ,01 natural sciences ,Shrub ,Enzyme assay ,Agronomy ,040103 agronomy & agriculture ,biology.protein ,0401 agriculture, forestry, and fisheries ,Ecosystem ,Soil fertility ,Cycling ,Water content ,Nitrogen cycle ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
Shrubs can induce spatial heterogeneity of soil nutrition and play a crucial role in dune stabilization in arid and semi-arid ecosystems. Soil enzyme activity can be used to investigate soil nutrient cycling, which further indicates soil recovery after sand stabilization. However, information regarding the effects of different shrubs on soil enzyme activity is scarce. To reveal and compare soil enzyme activities of two dominating sand-stabilizing shrubs, namely, Caragana korshinskii Kom. and Artemisia ordosica , we evaluated various hydrolase and oxidase enzymes involved in the carbon cycle (polyphenol oxidase, cellulose, and β-glucosidase) and nitrogen cycle (nitrate reductase and urease) at the shrub base (ASB), beneath the midcanopy (BMC), and in bare intershrub spaces (BIS). The results indicated that the sand-stabilizing shrubs improved soil nutrition and enzyme activity compared with bare soil. The effects varied with shrub type and position. Soil enzyme activities were greater in C. korshinskii than those in A. ordosica , and maximum enzyme activity was found at ASB, followed by BMC and BIS. All enzyme activities, except polyphenol oxidase, were higher at 0–5 cm depth. The enzyme activities exhibited similar seasonal patterns during the growing season, with relatively higher values in the summer rainy season than in the other seasons because of soil moisture and shrub growth. The results of this study suggest that sand-stabilizing shrubs, especially C. korshinskii , can increase soil nutrition and improve soil properties, thus playing a vital role in soil recovery in degraded areas of desert ecosystems.
- Published
- 2016
41. Interpretation of electrochemical impedance spectroscopy (EIS) circuit model for soils
- Author
-
Frank Y. Chen, Xiao hong Bai, Ya feng Zhang, and Peng ju Han
- Subjects
Materials science ,Soil water ,Metals and Alloys ,General Engineering ,Analytical chemistry ,Equivalent circuit ,Nyquist–Shannon sampling theorem ,Microstructure ,Biological system ,Dispersion (geology) ,Electrical impedance ,Water content ,Dielectric spectroscopy - Abstract
Based on three different kinds of conductive paths in microstructure of soil and theory of electrochemical impedance spectroscopy (EIS), an integrated equivalent circuit model and impedance formula for soils were proposed, which contain 6 meaningful resistance and reactance parameters. Considering the conductive properties of soils and dispersion effects, mathematical equations for impedance under various circuit models were deduced and studied. The mathematical expression presents two semicircles for theoretical EIS Nyquist spectrum, in which the center of one semicircle is degraded to simply the equivalent model. Based on the measured parameters of EIS Nyquist spectrum, meaningful soil parameters can easily be determined. Additionally, EIS was used to investigate the soil properties with different water contents along with the mathematical relationships and mechanism between the physical parameters and water content. Magnitude of the impedance decreases with the increase of testing frequency and water content for Bode graphs. The proposed model would help us to better understand the soil microstructure and properties and offer more reasonable explanations for EIS spectra.
- Published
- 2015
42. The stable isotopic composition variation characteristics of desert plants and water sources in an artificial revegetation ecosystem in Northwest China
- Author
-
Ma Xiongzhong, Rui Hu, Ya-feng Zhang, Xin-ping Wang, and Yan-xia Pan
- Subjects
Hydrology ,010504 meteorology & atmospheric sciences ,04 agricultural and veterinary sciences ,Vegetation ,01 natural sciences ,Soil plant atmosphere continuum ,Ecohydrology ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Precipitation ,Revegetation ,Water content ,Groundwater ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
Characterizing the dynamics of plant water availability and the mechanisms through which plants access available water sources are key challenges in ecohydrology, especially in arid and semi-arid regions. The establishment of artificial revegetation of different ages has formed vegetation landscapes with different chronological sequences in the southeast margin of the Tengger Desert. As an important regulatory factor of the Soil Plant Atmosphere Continuum (SPAC) system, changes in vegetation characteristics will affect the water uptake of the entire ecosystem. In this study, the δ2H and δ18O isotope ratios in precipitation, plant water, soil moisture, and underground water, and the δ13C isotope ratio of plant leaves were measured using the stable isotope technique for artificial revegetation used to fix the sand dunes in the Tengger Desert. The purpose of this study was to establish the isotope content and characteristics of potential water sources for plants and leaf carbon isotopes, to clarify whether the soil moisture condition and duration of sand-fixing influenced the isotopic signal, and to identify the main water source for desert plants. The results indicated that air temperature and amounts of precipitation were two important influencing factors in precipitation isotope ratio change. Soil water isotopic ratios were different under different water conditions, and under the same water conditions, the vertical variation in soil water isotopes in a single area and spatial variation at any depth for different revegetation areas were all significant (p 70%) concentrated at a soil depth of 20–150 cm. For Caragana korshinskii plants, the 60–150 cm soil layer was the main water supply layer, while the water contribution layer of Artemisia ordosica plants focused on the 20–100 cm soil layer and the contribution rate of shallow soil water increased with the increase of sand fixation time in older revegetation areas, regardless of the species used for revegetation.
- Published
- 2020
43. First Report of Seedling Stem Canker Disease of Acacia melanoxylon Caused by Pseudolagarobasidium acaciicola in China
- Author
-
Yongsan Zeng, X. R. Wang, B. S. Zeng, X. X. Li, Ya-Feng Zhang, S. Sun, and M. Cheng
- Subjects
Intergenic region ,biology ,Seedling ,Genetic marker ,Canker disease ,Botany ,Acacia melanoxylon ,Pseudolagarobasidium acaciicola ,Plant Science ,Fungal morphology ,biology.organism_classification ,Pathogenicity ,Agronomy and Crop Science - Published
- 2020
44. Relative contribution of biotic and abiotic factors to stemflow production and funneling efficiency: A long-term field study on a xerophytic shrub species in Tengger Desert of northern China
- Author
-
Ya-feng Zhang, Rui Hu, Yan-xia Pan, and Xin-ping Wang
- Subjects
0106 biological sciences ,Abiotic component ,Canopy ,Atmospheric Science ,Global and Planetary Change ,Stemflow ,010504 meteorology & atmospheric sciences ,ved/biology ,ved/biology.organism_classification_rank.species ,Growing season ,Forestry ,Biology ,01 natural sciences ,Arid ,Shrub ,Basal area ,Agronomy ,Ecosystem ,Agronomy and Crop Science ,010606 plant biology & botany ,0105 earth and related environmental sciences - Abstract
Stemflow production has been reported to be influenced by a suite of biotic and abiotic factors. Nevertheless, relative contributions of biotic and abiotic factors to stemflow production and funneling efficiency were largely unclear due to complex interactions among those factors. In this study, stemflow of nine xerophytic shrubs of Caragana korshinskii were measured in nearly nine growing seasons from 2010 to 2018 within a desert area of northern China, accompanying with observing on six biotic variables (shrub morphological attributes) and ten abiotic variables (meteorological conditions). We performed boosted regression trees (BRT) model to evaluate the relative contribution (θ) of each biotic and abiotic variable to stemflow volume (SFv), stemflow percentage (SFp), and funneling ratio (FR), associating with partial dependence plots (PDPs) to visualize the effects of individual explanatory variables on SFv, SFp, and FR, respectively. Generally, we observed that larger shrubs generated more SFv, while had lower SFp and FR. BRT analysis demonstrated that biotic variables outweighed abiotic variables by 1.5-fold as to their contribution to SFv, whereas abiotic variables prevailed for SFp and FR, respectively. Differences in θ between variables for SFv (CV = 146%) were much pronounced than for SFp (CV = 57%) and FR (CV = 26%), with the foremost three influential variables for SFv ranking in descending orders of θ by rainfall amount (33.2%), basal area (20.9%), projected canopy area (15.1%), and that for SFp by projected canopy area (13.2%), rainfall amount (13.0%), and air temperature (11.1%), and that for FR by antecedent dry period (9.1%), rainfall amount (8.4%), and wind speed (8.3%). The quantitative and mechanistic explanations regarding the effects of biotic and abiotic variables on three stemflow parameters from the present study are expected to be applicable to other shrub species within arid and semi-arid ecosystems.
- Published
- 2020
45. MicroRNA‑320 inhibits cell proliferation and invasion in breast cancer cells by targeting SOX4
- Author
-
Guo‑Dong Yao, Ya‑Feng Zhang, Xia Wang, Hong Liu, and Jun‑Wen Bai
- Subjects
0301 basic medicine ,Cancer Research ,Oncogene ,epithelial-mesenchymal transition ,Cancer ,Articles ,Biology ,Cell cycle ,medicine.disease ,medicine.disease_cause ,03 medical and health sciences ,SRY-box 4 ,breast cancer ,030104 developmental biology ,Breast cancer ,Oncology ,microRNA ,medicine ,Cancer research ,microRNA 320 ,Epithelial–mesenchymal transition ,Carcinogenesis ,A431 cells - Abstract
Dysregulation of microRNAs (miRs) can contribute to cancer development and progression. In the present study, the function and underlying molecular mechanisms of miR-320 in breast cancer tumorigenesis and progression were investigated. The results of a reverse transcription-quantitative polymerase chain reaction analysis demonstrated that miR-320 was frequently downregulated in breast cancer tissues compared with adjacent normal tissues. In addition, knockdown of miR-320 in breast cancer cell lines promoted cell proliferation and invasion in vitro, whereas miR-320 overexpression had the opposite effect. Furthermore, a Dual-Luciferase reporter assay indicated that SRY-box 4 (SOX4) is a direct target of miR-320, and the restoration of SOX4 in miR-320-overexpressing cells attenuated the tumor-suppressive effects of miR-320. Collectively, these results indicated that miR-320 acts as a tumor suppressor in breast cancer tumorigenesis and progression.
- Published
- 2017
46. Spatio-temporal variability of root zone soil moisture in artificially revegetated and natural ecosystems at an arid desert area, NW China
- Author
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Yan-xia Pan, Rui Hu, Xin-ping Wang, and Ya-feng Zhang
- Subjects
Hydrology ,Environmental Engineering ,Moisture ,Soil texture ,Soil morphology ,Soil science ,Management, Monitoring, Policy and Law ,Pedotransfer function ,Neutron probe ,Environmental science ,Soil horizon ,Spatial variability ,Water content ,Nature and Landscape Conservation - Abstract
Soil moisture is a major component of the hydrologic cycle, being highly variable and nonlinear in space and time. Knowledge of soil moisture regime, especially at the root zone, is critical to the management of water resources and restoration of vegetation. As such, techniques that allow identifying and reducing the number of samples for soil moisture analysis are required. In this study, a spatial variability and temporal stability analysis were used to analyze the volumetric soil moisture content of root zone collected by neutron probe at 36 days during three years in Shapotou, China. The specific concern was to investigate the temporal stability of soil moisture at different depths in the soil profile, determine the effects of soil and vegetation characteristics on temporal stability, and to conduct such a study in an area larger than 1 km 2 . Additionally, we aimed to determine whether temporally stable sites are invariable at different depths, and compare with temporally stable shallow layer (0–6, 0–15, 0–30 cm) sites that are previously identified by Wang et al. (2013b) in the same study area. Results showed that the mean soil profile moisture demonstrated a moderate spatial variability which decreased with increasing soil moisture content at 0–60 cm depth; however, the variability of soil moisture and CV were both low and no significant correlations were found at 0–300 cm depth. A high temporal stability existed at two deeper soil layers compared with the soil surface observed by Wang et al. (2013b) . The sampling locations, representative of the dry conditions in the field, were always more temporally stable. Identified representative locations at two depths well-represented the mean soil moisture content in our study area larger than 1 km 2 . Furthermore, strong correlations at two soil layers revealed that spatial patterns of sampling points were preserved for all depths and that time stability of shallow measurements was a good indicator of deep soil layer time stability. Soil texture was the primary influence factor on soil profile moisture temporal stability and the dependence of soil moisture temporal stability on soil texture was consistent among different soil depths. Knowledge of the underlying stable soil moisture distribution could provide a useful basis for precise water management in arid areas.
- Published
- 2015
47. Seasonal variation of net N mineralization under different biological soil crusts in Tengger Desert, North China
- Author
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Yan-xia Pan, Ning Chen, Xin-ping Wang, Hao Zhang, Ya-feng Zhang, and Rui Hu
- Subjects
Nutrient cycle ,Agronomy ,Ecology ,Soil water ,Biological soil crust ,Environmental science ,Growing season ,Nitrification ,Mineralization (soil science) ,Cycling ,complex mixtures ,Nitrogen cycle ,Earth-Surface Processes - Abstract
Biological soil crust (BSC) is a key biotic factor in desert areas and can significantly alter nutrient cycling. The interaction between seasonal climatic change and BSC can further modify nutrient cycling. Thus far, limited information has been provided regarding the effect of BSC on net soil nitrogen (N) transformation and their seasonal pattern in temperate desert areas. Therefore, we assessed the seasonal patterns of net soil N mineralization and nitrification in three microhabitats (moss-covered, cyanobacteria–lichen-covered, and bare soils) from October 2011 to September 2012 by using an intact soil core in situ incubation method. Seasonal variations in inorganic N pools, net N mineralization, and nitrification rates were observed. The seasonal patterns of net N transformation rates were greatly modified by soil temperature and moisture (highest in August and lowest in January). During non-growing season, net N immobilization was observed in the three microsites; a higher inorganic N content was observed in the moss-covered soil than in other soils. BSC increased the net soil N transformation rates during the early growing season but reduced the inorganic N content during the peak growing season. On the basis of these findings, we concluded that seasonal variation in climate significantly affected N transformation. The colonization and the development of BSC stimulated N cycling and storage in arid desert systems.
- Published
- 2015
48. Dependence of shrub canopy water storage on raindrop size in revegetated desert
- Author
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Hao Zhang, Yan-xia Pan, Xin-ping Wang, Ya-feng Zhang, and Rui Hu
- Subjects
Canopy ,Hydrology ,Biomass (ecology) ,biology ,ved/biology ,Shrub canopy ,Water storage ,ved/biology.organism_classification_rank.species ,biology.organism_classification ,Shrub ,Sand dune stabilization ,Xerophyte ,Environmental science ,Revegetation ,Water Science and Technology - Abstract
The aim of this study was to evaluate canopy water storage (CWS) of the co-dominant shrubs in the revegetation of sand dunes in northwest China. Our results indicated that CWS differed among the xerophyte taxa studied. The average CWS increased exponentially with decreased raindrop size. The time course of CWS in terms of leaf area indicated that Artemisia ordosica attains its peak value of 0.48 mm within 170 min. The corresponding values for Caragana korshinskii and Hedysarum scoparium were 0.38 mm and 178 min, and 0.32 mm and 161 min, respectively, implying that A. ordosica had a higher CWS than C. korshinskii and H. scoparium. Dry biomass was a desirable predictor for estimation of CWS for C. korshinskii and H. scoparium, and shrub volume for A. ordosica. Our results show that the dependence of CWS on raindrop size varied in accordance with the shrub canopy structure. Editor Z.W. Kundzewicz
- Published
- 2015
49. Clinical and laboratory characteristics in patients suffering from general paresis in the modern era
- Author
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Kun Gao, Wei-Hong Zheng, Jian-Jun Niu, Yu-Yan Chen, Hui-Lin Zhang, Li-Rong Lin, Tian-Ci Yang, Man-Li Tong, Xiao-Zhen Zhu, Long Liu, Fuyi Chen, Jin-Yi Fan, Ya-Feng Zhang, Li-Li Liu, Xin-Hui Qiu, and Qiao Zhang
- Subjects
Adult ,Male ,medicine.medical_specialty ,Electroencephalography ,Neurosyphilis ,Cerebrospinal fluid ,CSF pleocytosis ,Internal medicine ,medicine ,Humans ,Treponema pallidum ,Aged ,Retrospective Studies ,Paresis ,medicine.diagnostic_test ,business.industry ,Gold standard ,Magnetic resonance imaging ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Neurology ,Female ,Neurology (clinical) ,medicine.symptom ,Tomography, X-Ray Computed ,business - Abstract
Background No gold standard currently exists for the diagnosis of general paresis (GP), thus often resulting in unnecessarily delayed therapeutic decision. Methods A retrospective chart review was performed for 85 inpatients with GP in Zhongshan Hospital, Medical College of Xiamen University, and the characteristics of their clinical profiles, serum and cerebrospinal fluid (CSF) examinations, neuroimaging examination, and electroencephalogram (EEG) data were analyzed. Results Among the 85 GP patients, the clinical symptoms that were frequently observed upon admission included a variety of psychiatric–behavioral symptoms and varying degrees of cognitive impairment. All of the patients had positive serum Treponema pallidum particle agglutination (TPPA) assays, 96.47% of the patients had positive CSF TPPA assays, and 41.18% of the patients had both CSF pleocytosis and elevated CSF protein levels. Focal atrophy in one cerebral region or in multiple regions was evident in neuroimages. The EEG data primarily showed slightly abnormal EEG activity. Conclusion These results demonstrate the complexity of the clinical characteristics of GP and highlight the importance of early diagnosis.
- Published
- 2015
50. The influence ofCaragana korshinskiishrub on soil and hydrological properties in a revegetation-stabilized desert ecosystem
- Author
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Xinrong Li, Xin-ping Wang, Ya-feng Zhang, Rui Hu, Yan-xia Pan, and Hao Zhang
- Subjects
Hydrology ,Soil test ,ved/biology ,Soil organic matter ,ved/biology.organism_classification_rank.species ,Soil science ,Arid ,Shrub ,Spatial heterogeneity ,Soil water ,Environmental science ,Ecosystem ,Revegetation ,Water Science and Technology - Abstract
Shrub-induced spatial heterogeneity of soil and hydrological properties are common in arid and semi-arid ecosystems. To examine the influence of shrubs on spatial patterns of soil physical, chemical and hydrological properties, the typical sand-fixation species, Caragana korshinskii, was studied in the Shapotou area of the Tengger Desert, China. Miniature cylinder infiltrometers were used to quantify the spatial variations of infiltration rate in the soils, and were installed at 20-cm intervals around the shrubs. Meanwhile, soil samples were collected at 0–5 cm depth every 10 cm to analyse their physical and chemical properties and soil moisture content. The results indicate that the various measured parameters showed a gradational change from sub-canopy to open space. The establishment of shrubs formed obvious “fertile islands” where more soil nutrients collected. The total nitrogen (TN), soil organic matter (SOM), electrical conductivity (EC) and surface soil moisture content decreased gradually...
- Published
- 2014
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