80 results on '"Ya Feng Zhang"'
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2. Experimental Study on the Evolution Mechanism of Landslide with Retaining Wall Locked Segment
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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.
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- 2022
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3. 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
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4. 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
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5. 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
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6. 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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7. 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.
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- 2021
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8. 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
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9. 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
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10. 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
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11. 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
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12. The effect of different biocrusts on soil hydraulic properties in the Tengger Desert, China
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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
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13. 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
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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
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- 2019
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14. 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
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15. 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
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16. 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
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17. 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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18. Sulfate radical-based technology for the removal of 2-methylisoborneol and 2-methylisoborneol-producing algae in drinking water sources
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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.
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- 2019
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19. Evapotranspiration of xerophytic shrub Salsola passerina and Reaumuria soongorica in an arid desert ecosystem of NW China
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Hao-jie Xu, Yan-xia Pan, Ya-feng Zhang, Rui Hu, Jin Yanxia, Xin-ping Wang, and Wei Shi
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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.
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- 2018
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20. The effect of biological soil crusts on soil moisture dynamics under different rainfall conditions in the Tengger Desert, China
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Yan-xia Pan, Rui Hu, Xin-ping Wang, Ya-feng Zhang, Wei Shi, and Jin Yanxia
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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
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21. Design of the Integral Field Measurement System of Dipole Magnets
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Wei Chen, Bin Qin, Ya Feng Zhang, Jun Yang, Ying Cai Xie, Tao Liu, and Hui Liang
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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.
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- 2018
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22. Effects of Different Matrix on Interface and Compression Fracture Behavior of WC Particles Reinforced Iron Matrix Composites
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Feng Rui Chen, Ye Hua Jiang, Zu Lai Li, Quan Shan, Fei Zhang, and Ya Feng Zhang
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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.
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- 2018
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23. Effects of ultrasound on the formation of oxidative pigments in a model red wine solution containing glutathione
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Bo-Yu Chen, Ya-Feng Zhang, Er-Chun Li, Bao-Shan Zhang, and Qing-An Zhang
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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.
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- 2021
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24. Stemflow volume per unit rainfall as a good variable to determine the relationship between stemflow amount and morphological metrics of shrubs
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Xin-ping Wang, Ya-feng Zhang, Yan-xia Pan, and Rui Hu
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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 .
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- 2017
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25. Differential intra-specific stemflow funnelling efficiencies of Caragana korshinskii within arid desert ecosystems
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Xin-ping Wang, Ya-feng Zhang, Rui Hu, and Yan-xia Pan
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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
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26. Throughfall and its spatial variability beneath xerophytic shrub canopies within water-limited arid desert ecosystems
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Ya-feng Zhang, Yan-xia Pan, Rui Hu, and Xin-ping Wang
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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
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- 2016
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27. Comparison of diurnal dynamics in evaporation rate between bare soil and moss-crusted soil within a revegetated desert ecosystem of northwestern China
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Yan-xia Pan, Ya-feng Zhang, Xin-ping Wang, and Rui Hu
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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.
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- 2016
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28. Insight into the influence of sand-stabilizing shrubs on soil enzyme activity in a temperate desert
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Jin Yanxia, Ning Chen, Wei Shi, Ya-feng Zhang, Rui Hu, and Xin-ping Wang
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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.
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- 2016
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29. Interpretation of electrochemical impedance spectroscopy (EIS) circuit model for soils
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Frank Y. Chen, Xiao hong Bai, Ya feng Zhang, and Peng ju Han
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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.
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- 2015
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30. Spatio-temporal variability of root zone soil moisture in artificially revegetated and natural ecosystems at an arid desert area, NW China
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Yan-xia Pan, Rui Hu, Xin-ping Wang, and Ya-feng Zhang
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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.
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- 2015
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31. Seasonal variation of net N mineralization under different biological soil crusts in Tengger Desert, North China
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Yan-xia Pan, Ning Chen, Xin-ping Wang, Hao Zhang, Ya-feng Zhang, and Rui Hu
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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.
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- 2015
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32. Dependence of shrub canopy water storage on raindrop size in revegetated desert
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Hao Zhang, Yan-xia Pan, Xin-ping Wang, Ya-feng Zhang, and Rui Hu
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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
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- 2015
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33. Clinical and laboratory characteristics in patients suffering from general paresis in the modern era
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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
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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.
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- 2015
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34. MicroRNA‑320 inhibits cell proliferation and invasion in breast cancer cells by targeting SOX4
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Guo‑Dong Yao, Ya‑Feng Zhang, Xia Wang, Hong Liu, and Jun‑Wen Bai
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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.
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- 2017
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35. 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
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Ya-feng Zhang, Rui Hu, Yan-xia Pan, and Xin-ping Wang
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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.
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- 2020
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36. Effects of the microstructure of twin roll cast and hot rolled plates on the surface quality of presensitized plates
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Feng Zhou, Ya-feng Zhang, Chao-Qi Zhao, and Yuan-zhi Zhu
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Materials science ,Scanning electron microscope ,Mechanical Engineering ,Metallurgy ,Metals and Alloys ,Microstructure ,Surface cleaning ,Hot rolled ,law.invention ,stomatognathic system ,Optical microscope ,Geochemistry and Petrology ,Mechanics of Materials ,law ,Casting (metalworking) ,Materials Chemistry ,Graphite ,Residual carbon - Abstract
The effect of the microstructure of plates fabricated both in the traditional process, involving casting, hot rolling and cold rolling (HR), and in the novel twin roll casting + cold rolling (TRC) process on the surface quality of presensitized (PS) plates was analyzed by optical microscopy (OM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDXS). The formation of pores on the surface of the electrolyzed HR plate could be attributed to the presence of approximately 1-μm-sized large Al-Fe precipitates in the HR plate compared to the smaller precipitates in the TRC plate. Moreover, residual graphite lubricants used during the TRC process were entrapped on the surface of the TRC plate during the subsequent rolling process. The entrapped pollutants tended to further deteriorate the formation of pores on the surface of the TRC plate, and no residual carbon was detected on the surface of the HR plate. Furthermore, the surface quality of the TRC plate can be improved by surface cleaning before the cold rolling process, which could dramatically lower the residual graphite on the surface.
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- 2014
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37. Characterization of the classical biological false-positive reaction in the serological test for syphilis in the modern era
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Fan Liu, Li-Rong Lin, Tian-Ci Yang, Ya-Feng Zhang, Xiao-Jing Guo, Ya Xi, Qiao Zhang, Yu-Yan Chen, Ge-Ling Huang, Man-Li Tong, Hui-Lin Zhang, Song-Jie Huang, Jie Jiang, and Li-Li Liu
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Adult ,Male ,China ,medicine.medical_specialty ,Adolescent ,Immunology ,Population ,Comorbidity ,Disease ,urologic and male genital diseases ,Rapid plasma reagin ,Serology ,Young Adult ,Risk Factors ,Internal medicine ,medicine ,Humans ,Immunology and Allergy ,False Positive Reactions ,Syphilis ,Treponema pallidum ,education ,Aged, 80 and over ,Pharmacology ,education.field_of_study ,Treponema ,medicine.diagnostic_test ,biology ,business.industry ,Salpingitis ,medicine.disease ,biology.organism_classification ,Syphilis Serodiagnosis ,Titer ,Female ,business ,Follow-Up Studies - Abstract
To characterize the CBFP reaction in the modern era, we analyzed the results of parallel rapid plasma reagin (RPR) and Treponema pallidum particle agglutination (TPPA) tests from a total of 63,765 blood samples obtained at Zhongshan Hospital in the Medical College of Xiamen University from May 2008 to February 2013. Among the 63,765 tested blood samples, 206 (0.32%) had the CBFP reaction. In multivariate analysis, an increased likelihood of the CBFP reaction was associated with female subjects, subjects ≥80years old, and subjects between 16 and 35years old (P
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- 2014
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38. Incidence and Risk Factors for the Prozone Phenomenon in Serologic Testing for Syphilis in a Large Cohort
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Xiao-Jing Guo, Ya Xi, Long Liu, Fuyi Chen, Man-Li Tong, Li-Rong Lin, Tian-Ci Yang, Yu-Yan Chen, Song-Jie Huang, Ya-Feng Zhang, Hui-Lin Zhang, Li-Li Liu, and Qiao Zhang
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Adult ,Male ,Microbiology (medical) ,Pediatrics ,medicine.medical_specialty ,Adolescent ,Rapid plasma reagin ,Cohort Studies ,Neurosyphilis ,Young Adult ,Syphilis Serodiagnosis ,Pregnancy ,Risk Factors ,Agglutination Tests ,Humans ,Medicine ,Syphilis ,Child ,Reagins ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Incidence ,Incidence (epidemiology) ,Infant, Newborn ,Antibody titer ,Infant ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Titer ,Infectious Diseases ,Child, Preschool ,Immunology ,Female ,business - Abstract
Background The prozone phenomenon is known to be associated with high antibody titers; other associations, such as host factors, have not been elucidated. Methods A retrospective analysis was conducted to evaluate the incidence of the prozone phenomenon of the syphilis rapid plasma reagin (RPR) test among 46 856 clinical samples, between June 2010 and June 2013. Logistic regression was used to analyze the risk factors of the prozone phenomenon. Results Our results showed that the incidence of the prozone phenomenon was low (0.83%) and could occur during any clinical phase, particularly during primary and secondary syphilis. Pregnancy and neurosyphilis were associated with the prozone phenomenon; sex, age, and whether the patient had been treated were not. The results also revealed that the prozone phenomenon not only occurred in patients with a high titer but also could occur in patients with a moderate/low titer. In fact, almost 31% of the patients with the prozone phenomenon had titers ≤1:16. Conclusions The prozone phenomenon in the RPR test was associated with the phase of syphilis, pregnancy, and neurosyphilis as well as a range of RPR titers between 1:8 and 1:512. This latter finding is in contrast to previous reports that the prozone phenomenon is associated with very high RPR titers.
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- 2014
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39. The response mechanisms of soil N mineralization under biological soil crusts to temperature and moisture in temperate desert regions
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Xin-ping Wang, Ya-feng Zhang, Rui Hu, Hao Zhang, and Yan-xia Pan
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Agronomy ,Moisture ,Insect Science ,Soil water ,Biological soil crust ,Soil Science ,Environmental science ,Nitrification ,Ecosystem ,Mineralization (soil science) ,Cycling ,Microbiology ,Water content - Abstract
Soil nitrogen (N) mineralization is an important component of the N cycling process in desert ecosystems. However, the effects of biological soil crust (BSC), especially different patterns of BSCs (i.e. moss, algae-lichen), on net nitrification and N mineralization rates under climate-change conditions are still largely unexplored. To investigate the effects of temperature and moisture on net nitrification and N mineralization rates in BSC-dominated desert soils, and to highlight the regulatory role of BSC on N availability in the Tengger Desert, China, intact soil cores from three microhabitats (moss-covered, algae-lichen-covered, and bare soil) were incubated at six temperatures (−10, 5, 15, 25, 35, and 40 °C) and four moisture levels (29, 58, 85, and 170% field water content, FWC). Generally, moss-covered soil exhibited the highest net N transformation rate, whereas, algae-lichen-covered soil inhibited the nitrification process. Incubation temperature and moisture significantly affected net nitrification and N mineralization rates in all three microhabitats, in general that values were higher at the higher temperature (i.e. 25, 35, and 40 °C) compared to lower temperature (i.e. −10, 5, 15 °C). The net N mineralization rate for the three microhabitats peaked at 85% FWC. Overall, results indicated that BSCs, especially moss-dominated soils, increase net N transformation rate and N availability. Thus, they can make a contribution to plant growth and play a positive role in primary productivity under climate change in arid areas.
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- 2014
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40. Condensation of water vapour on moss-dominated biological soil crust, NW China
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Yan-xia Pan, Ya-feng Zhang, Rui Hu, Hao Zhang, and Xin-ping Wang
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Salinity ,Hydrology ,Dew point ,Condensation ,Biological soil crust ,General Earth and Planetary Sciences ,Cloud condensation nuclei ,Environmental science ,Relative humidity ,Atmospheric sciences ,Porosity ,Water vapor - Abstract
Characteristics of water vapour condensation, including the onset, duration, and amount of water vapour condensation on moss-dominated biological soil crust (BSC) and dune sand were studied under simulated conditions with varying air temperature and relative humidity. The simulations were performed in a plant growth chamber using an electronic balance recording the weight of condensation. There was a positive linear correlation between the water vapour condensation and relative humidity while the mean temperature was negatively linearly related to amounts of water vapour condensation for both soil surfaces. The amount of water vapour condensation on BSC and dune sand can be described by the difference between air temperature and dew point with an exponential function, indicating that when the difference of air temperature and dew point exceeds a value of 35.3◦C, there will be zero water vapour condensed on BSC. In contrast, when the difference of air temperature and dew point exceeds a value of 20.4◦C, the water vapour condensation will be zero for dune sand. In general, when the air is fully saturated with water and the dew point is equal to the current air temperature, the water vapour condensed on BSC attained its maximum value of 0.398 mm, whereas it was 0.058 mm for dune sand. In comparison, water vapour condensed on BSC was at a relatively high temperature and low relative humidity, while we did not detect water vapour condensation on the dune sand under the similar conditions. Physical and chemical analyses of the samples pointed to a greater porosity, high content of fine particles, and high salinity for BSC compared to the dune sand. These results highlight that soil physicochemical properties are the likely factors influencing the mechanism of water vapour condensation under specific meteorological conditions, as onset was earlier and the duration was longer for water vapour condensation on BSC in comparison with that of dune sand. This contributed to the greater amount of vapour absorbed on BSC compared to the dune sand under an identical meteorological condition. The feedback of water vapour condensation on BSC formation and its contribution to sustain the revegetation desert ecosystems was discussed.
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- 2014
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41. Analysis of 3 Algorithms for Syphilis Serodiagnosis and Implications for Clinical Management
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Hui-Lin Zhang, Ya-Feng Zhang, Qiao Zhang, Long Liu, Man-Li Tong, Ya Xi, Fuyi Chen, Song-Jie Huang, Li-Rong Lin, Tian-Ci Yang, Xiao-Jing Guo, Li-Li Liu, and Yu-Yan Chen
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Adult ,Male ,Serum ,Microbiology (medical) ,Adolescent ,Concordance ,Sensitivity and Specificity ,Rapid plasma reagin ,Young Adult ,Syphilis Serodiagnosis ,medicine ,Humans ,Treponema pallidum ,Medical diagnosis ,Child ,Aged ,Aged, 80 and over ,Treponema ,biology ,medicine.diagnostic_test ,business.industry ,Infant ,Gold standard (test) ,Middle Aged ,biology.organism_classification ,medicine.disease ,Cross-Sectional Studies ,Infectious Diseases ,Child, Preschool ,Immunoassay ,Female ,Syphilis ,business ,Algorithm ,Algorithms - Abstract
Background. Algorithms for the diagnosis of syphilis continue to be a source of great controversy, and numerous test interpretations have perplexed many clinicians. Methods. We conducted a cross-sectional study of 24 124 subjects to analyze 3 syphilis testing algorithms: traditional algorithm, reverse algorithm, and the European Centre for Disease Prevention and Control (ECDC) algorithm. Every serum sample was simultaneously evaluated using the rapid plasma reagin, Treponema pallidum particle agglutination, and chemiluminescence immunoassay tests. With the results of clinical diagnoses of syphilis as a gold standard, we evaluated the diagnostic accuracy of the 3 syphilis testing algorithms. The κ coefficient was used to compare the concordance between the reverse algorithm and the ECDC algorithm. Results. Overall, 2749 patients in our cohort were diagnosed with syphilis. The traditional algorithm had the highest negative likelihood ratio (0.24), a missed diagnosis rate of 24.2%, and only 75.81% sensitivity. However, both the reverse and ECDC algorithms had higher diagnostic efficacy than the traditional algorithm. Their sensitivity, specificity, and accuracy were 99.38%–99.85%, 99.98%–100.00%, and 99.93%–99.96%, respectively. Moreover, the overall percentage of agreement and κ value between the reverse and the ECDC algorithms were 99.9% and 0.996, respectively. Conclusions. Our research supported use of the ECDC algorithm, in which syphilis screening begins with atreponemal immunoassay that is followed by a second, different treponemal assay as a confirmatory test in highprevalence populations. In addition, our results indicated that nontreponemal assay is unnecessary for syphilis diagnosis but can be recommended for determining serological activity and the effect of syphilis treatment.
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- 2014
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42. Association between neurosyphilis and diabetes mellitus: Resurgence of an old problem 神经梅毒与糖尿病的关系:'旧事'再现
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Li-Rong Lin, Hui-Lin Zhang, Tian-Ci Yang, Yu-Yan Chen, Jie Jiang, Qiao Zhang, Fuyi Chen, Man-Li Tong, Xiao-Jing Guo, Wei-Hong Zheng, Ya-Feng Zhang, Song-Jie Huang, Ya Xi, Li-Li Liu, and Long Liu
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Neurosyphilis ,medicine.medical_specialty ,Endocrinology ,business.industry ,Endocrinology, Diabetes and Metabolism ,Internal medicine ,Diabetes mellitus ,medicine ,medicine.disease ,business - Abstract
Background Syphilis, a sexually transmitted disease, is commonly referred to as the “great imitator” because of its wide-ranging clinical presentations. Recently, we noticed that patients with neurosyphilis (NS) seemed to be more susceptible to complications of diabetes mellitus (DM). This is an interesting phenomenon, but it also puzzles clinicians because of scant knowledge about this situation. Methods A case-control study was conducted to explore the association between NS and DM. Clinical data and the prevalence of DM among NS patients, patients with syphilis but not NS (syphilis/non-NS), non-syphilis patients, and healthy controls were analyzed. In addition, we explored the time of occurrence of NS and DM. Results Fasting plasma glucose and HbA1c levels in NS patients were significantly higher than in syphilis/non-NS patients, non-syphilis patients, and healthy controls (P
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- 2014
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43. Temporal stability analysis of surface and subsurface soil moisture for a transect in artificial revegetation desert area, China
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Yan-xia Pan, Deqiang Dou, Xin-ping Wang, Rui Hu, Ya-feng Zhang, and Hao Zhang
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Hydrology ,Pedotransfer function ,Soil water ,Spatial ecology ,Elevation ,Environmental science ,Soil science ,Edaphic ,Revegetation ,Transect ,Water content ,Water Science and Technology - Abstract
Summary Temporal stability analysis is a statistical approach for describing the persistence of spatial patterns and characteristic behavior of soil moisture. Using temporal stability method, we aimed to identify statistically stable locations to estimate mean soil moisture content and examine the feasibility of confirming temporally stable locations by using other properties that were themselves relatively temporally stable. The temporal stability of near-surface soil moisture contents were investigated at three depths at the hillslope scale in an artificial revegetation desert area, China. Soil moisture were measured at soil depth of 0–6, 0–15 and 0–30 cm, using temporary frequency-domain reflectometry (FDR) and time domain reflectometry (TDR), at ten locations along a hillslope with relatively homogeneous soil properties and vegetation cover but contrasting topography during May to September in 2006. Summary variables were determined at corresponding locations. Results indicated that strong temporal persistence existed at three depths, and the temporal stability was more pronounced at deep soil layer than at soil surface. The temporal stability characteristics were relatively lack in a state of transition from wet to dry. Identified statistically stable locations at three depths represented well for the mean soil moisture content; the offset values were 0.011, 0.002 and 0.001 m3 m−3 at 0–6, 0–15 and 0–30 cm depth, respectively. The representative site for 0–6 cm soil layer can serve as a good indicator of soil moisture at other depths. Elevation and soil properties were the leading factors affecting the spatial and temporal distribution of soil moisture at the hillslope scale. The mean soil moisture contents at different depths can be predicted by other topographic and edaphic factors. This study is expected to be useful in characterizing mean soil moisture content in soil profiles on a hillslope scale, which helps to a good management of soil water on sloping land in desert areas.
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- 2013
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44. Heterogeneity of soil surface temperature induced by xerophytic shrub in a revegetated desert ecosystem, northwestern China
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Yan-xia Pan, Hao Zhang, Rui Hu, Ya-feng Zhang, and Xin-ping Wang
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Canopy ,ved/biology ,ved/biology.organism_classification_rank.species ,Solar altitude ,Diurnal temperature variation ,Soil science ,Biota ,Vegetation ,Atmospheric sciences ,Shrub ,General Earth and Planetary Sciences ,Environmental science ,Ecosystem ,Soil surface temperature - Abstract
Variation characteristics of the soil surface temperature induced by shrub canopy greatly affects the near-surface biological and biochemical processes in desert ecosystems. However, information regarding the effects of shrub upon the heterogeneity of soil surface temperature is scarce. Here we aimed to characterize the effects of shrub (Caragana korshinskii) canopy on the soil surface temperature heterogeneity at areas under shrub canopy and the neighbouring bare ground. Diurnal variations of soil surface temperature were measured at areas adjacent to the shrub base (ASB), beneath the midcanopy (BMC), and in the bare intershrub spaces (BIS) at the eastern, southern, western and northern aspects of shrub, respectively. Results indicated that diurnal mean soil surface temperature under the C. korshinskii canopy (ASB and BMC) was significantly lower than in the BIS, with the highest in the BIS, followed by the BMC and ASB. The diurnal maximum and diurnal variations of soil surface temperatures under canopy vary strongly with different aspects of shrub with the diurnal variation in solar altitude, which could be used as cues to detect safe sites for under-canopy biota. A significant empirical linear relationship was found between soil surface temperature and solar altitude, suggesting an empirical predicator that solar altitude can serve for soil surface temperature. Lower soil surface temperatures under the canopy than in the bare intershrub spaces imply that shrubs canopy play a role of ‘cool islands’ in the daytime in terms of soil surface temperature during hot summer months in the desert ecosystems characterized by a mosaic of sparse vegetation and bare ground.
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- 2013
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45. Stemflow in two xerophytic shrubs and its significance to soil water and nutrient enrichment
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Rui Hu, Hao Zhang, Yan-xia Pan, Ya-feng Zhang, and Xin-ping Wang
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Stemflow ,Ecology ,ved/biology ,ved/biology.organism_classification_rank.species ,Throughfall ,Shrub ,Basal area ,Nutrient ,Agronomy ,Soil water ,Environmental science ,Soil horizon ,Precipitation ,Ecology, Evolution, Behavior and Systematics - Abstract
Shrub canopies are expected to funnel substantial amounts of intercepted rainwater with enriched nutrients as stemflow to shrub base in the desert ecosystems characterized by limited water and nutrients. However, lacking are quantitative studies on the water and nutrient enrichment of stemflow at the shrub basal area. In this study, stemflow were quantified for two xerophytic shrubs (Caragana korshinskii and Artemisia ordosica) in a revegetated desert ecosystem of Shapotou area in northwestern China. We also measured the ion concentrations of total nitrogen (TN), total phosphors (TP), NH4 +–N, NO3 −–N, Na+, K+, Ca2+, Mg2+, Cl−, SO4 2− and the pH and electric conductivity (EC) in stemflow, throughfall and bulk precipitation. Results indicated that stemflow accounted for 8.8 and 2.8 % of the gross rainfall for C. korshinskii and A. ordosica, respectively. Individual stemflow linearly increased with increasing rainfall depth. Stemflow increased with rainfall intensity when rainfall intensity was less than 2 mm h−1 but showed decreased tendency thereafter. An antecedent precipitation of 1.3 and 1.6 mm was necessary for stemflow initiation for C. korshinskii and A. ordosica, respectively. The mean (confidence intervals, α = 0.05) funneling ratio was 82 (17) for C. korshinskii and 26 (7) for A. ordosica. Ion concentrations in stemflow were higher than in throughfall, and the concentration of most of the ions measured were significantly higher (p
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- 2013
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46. Influence of shrub canopy morphology and rainfall characteristics on stemflow within a revegetated sand dune in the Tengger Desert, NW China
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Ya-feng Zhang, Xin-ping Wang, Rui Hu, Xiao-jun Li, Yan-xia Pan, Zheng-ning Wang, and Hao Zhang
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Abiotic component ,Canopy ,Hydrology ,Water balance ,Stemflow ,Morphology (linguistics) ,Environmental science ,Revegetation ,Leaf area index ,Water Science and Technology ,Sand dune stabilization - Abstract
Stemflow of xerophytic shrubs was monitored on event basis within a revegetated sand dune. Quantity of stemflow showed a clear species-specific dependence in combination with the rainfall characteristics. Results obtained revealed that for ovate-leaved C. korshinskii with an inverted cone-shaped canopy and smooth bark, the quantity of stemflow in depth accounted for 7.2% of the individual gross rainfall, while it was 2.0% for needle-leaved A. ordosica with a cone-shaped canopy and coarse bark. There were significant positive linear relationships between stemflow and individual gross rainfall and rainfall intensity for the two shrubs. An individual gross rainfall of 1.4 and 1.8 mm was necessary for stemflow generation for C. korshinskii and A. ordosica, respectively. Multiple regression analysis showed that the abiotic and biotic variables including the individual gross rainfall, mean windspeed (WS), canopy height, branch length, and canopy volume have significant influence on stemflow for C. korshinskii, whereas for A. ordosica, the notable influencing variables were individual gross rainfall, stem diameter, and leaf area index. Generally, WS has less effect on stemflow than that of rainfall for A. ordosica. The correlation relationship between individual gross rainfall and funneling ratio showed that the funneling ratio attains its peak when the gross rainfall is 13 and 16 mm for C. korshinskii and A. ordosica, respectively, implying that the canopy morphology emerged as determining factors on funneling ratio decrease when the individual gross rainfall exceeds these values. In comparison, higher WS increased the funneling ratio remarkably for C. korshinskii than A. ordosica due partly to the greater branch length and canopy projection area in C. korshinskii. Funneling ratio can be used as an integrated variable for the effects of canopy morphology and rainfall characteristics on stemflow. The implication of stemflow on water balance and its contribution to sustain the shrubs and the revegetation efforts was discussed. Copyright (c) 2013 John Wiley & Sons, Ltd.
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- 2013
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47. The effect of angiotensin-converting enzyme inhibitor use on bone loss in elderly Chinese
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Timothy Kwok, Ping-Chung Leung, Ya-Feng Zhang, and Ling Qin
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Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Osteoporosis ,Angiotensin-Converting Enzyme Inhibitors ,Cohort Studies ,Sex Factors ,Endocrinology ,Asian People ,Bone Density ,Continuous use ,Internal medicine ,medicine ,Humans ,Orthopedics and Sports Medicine ,Pelvic Bones ,Aged ,Femoral neck ,biology ,Femur Neck ,business.industry ,Confounding ,Angiotensin-converting enzyme ,General Medicine ,medicine.disease ,Surgery ,Bone Diseases, Metabolic ,medicine.anatomical_structure ,ACE inhibitor ,Orthopedic surgery ,biology.protein ,Female ,business ,Osteoporotic Fractures ,medicine.drug ,Cohort study - Abstract
In this study we analyzed the independent effect of angiotensin-converting enzyme (ACE) inhibitor use on bone loss in elderly Chinese. The subjects were from two cohort studies which investigated the risk factors of osteoporotic fractures in Hong Kong-dwelling elderly Chinese. A total of 2161 subjects (1280 male, 881 female) were selected for this analysis. The results showed that unadjusted annualized percentage bone loss of male ACE inhibitor users was not different from non-users; however, female ACE inhibitor users had significantly greater bone loss both in total hip and femoral neck than non-users. After adjusting for significant confounders, female continuous ACE inhibitor users had significantly greater bone loss at total hip and femoral neck. In conclusion, continuous use of ACE inhibitors over 4 years was associated with increased bone loss in total hip and femoral neck in older Chinese women.
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- 2012
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48. Fabrication and thermal conductivity of copper matrix composites reinforced by tungsten-coated carbon nanotubes
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Xuebing Liang, Junhui Nie, Chengchang Jia, Yi Li, Xian Jia, and Ya-feng Zhang
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Materials science ,Mechanical Engineering ,Thermal resistance ,Metals and Alloys ,chemistry.chemical_element ,Spark plasma sintering ,Chemical vapor deposition ,Carbon nanotube ,Tungsten ,Copper ,law.invention ,Metal ,Thermal conductivity ,chemistry ,Geochemistry and Petrology ,Mechanics of Materials ,law ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,Composite material - Abstract
Carbon nanotubes (CNTs) were coated by tungsten using metal organic chemical vapor deposition. Magnetic stirring was employed to disperse the W-coated CNTs (W-CNTs) in a Cu matrix, and then, the mixed powders were consolidated by spark plasma sintering. The W-CNTs obtained a uniform dispersion within the Cu matrix when the W-CNT content was less than 5.0vol%, but high content of W-CNTs (10vol%) resulted in the presence of clusters. The W-CNT/Cu composites containing low content of W-CNTs (
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- 2012
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49. Comparison of hydraulic behaviour of unvegetated and vegetation-stabilized sand dunes in arid desert ecosystems
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Angelo Basile, Anna Tedeschi, Antonio Coppola, Roberto De Mascellis, Xin-ping Wang, Alessandro Comegna, Rui Hu, Gui-jing Quan, Ya-feng Zhang, and Yan-xia Pan
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Hydrology ,Ecology ,Soil science ,Aquatic Science ,Infiltration (HVAC) ,Sand dune stabilization ,Hydraulic conductivity ,Soil water ,Soil horizon ,Infiltrometer ,Revegetation ,Water content ,Ecology, Evolution, Behavior and Systematics ,Geology ,Earth-Surface Processes - Abstract
Revegetation was one of most successful measures to restore desert sand dunes and to improve regional eco-environments in the Tengger Desert, Northwest China. The potential for soil moisture replenishment by precipitation in the revegetation restored desert ecosystems is influenced strongly by the hydraulic properties of the surface soils. Steady-state infiltration rates from tension disc infiltrometer were measured at revegetation restored desert soils (VS) and unvegetated sand dunes (SD), respectively. Results indicated that the site specific VS and SD hydraulic properties differed significantly. Compared with SD, the long term VS has the effect of decreasing the hydraulic conductivity of the surface soil, while increasing the capillary effect on the infiltration rate. Averagely, the hydraulic conductivity of VS was 0 center dot 43 times of SD at the near saturation conditions. At VS, tension infiltration were dominated by capillarity effect more than that of SD, which were ascribed to the differences in soil properties where the former has a higher amount of finer particles, organic matters content and lower bulk densities. Accordingly, the hydraulically functioning mean pore sizes were larger at SD, where the gravity effect dominated the tension infiltration process. Therefore, in the study area under the pulse precipitation events in the growing seasons, VS contains more soil water by capillarity effect than SD does, which would contribute to shallow rooted herbage and cryptogam water consumption. Nevertheless, looking at the whole soil profile, for the actual rainfall water regimes, VS has insignificant effects on the soil profile water regime, with unchanged deep fluxes. Copyright (c) 2012 John Wiley & Sons, Ltd.
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- 2012
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50. Diurnal Relationship Between the Surface Albedo and Surface Temperature in Revegetated Desert Ecosystems, Northwestern China
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Rui Hu, Ya-feng Zhang, Yan-xia Pan, and Xin-ping Wang
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Hydrology ,Daytime ,Forenoon ,Diurnal temperature variation ,Soil Science ,Environmental science ,Noon ,Albedo ,Revegetation ,Atmospheric sciences ,Arid ,Sand dune stabilization - Abstract
Quantification of the relationship between surface albedo and surface temperature was done by analyzing measured diurnal variations of surface albedo and surface temperature on the biological soil crusts and sand dunes within vegetation-stabilized desert ecosystems. The surface albedos and surface temperatures of sand dunes and biological soil crusts were measured concurrently over field plots of the moving sand area and the artificially revegetated area established in 1964 in Shapotou area, on the southeastern edge of the Tengger Desert. Results indicated that the diurnal variation of surface albedo for both dry surfaces showed an upward-facing parabolic curve on clear days and was symmetrical at about local noon. Whereas, the diurnal trend of surface temperature was opposite to that of surface albedo in the daytime and asymmetrical at about local noon times. Thereby, the data were empirically divided into forenoon and afternoon data with respect to local noon to analyze the relationship between surface ...
- Published
- 2012
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